Each Man Kills the Thing He Loves Essay

â€Å"It seems to me that we all look at Nature too much, and live with her too little† This quote provides a philosophical insight into the main theme I will explore within my chosen poems. Nature is defined as the phenomena of the physical world collectively, including plants, animals, the landscape, and other features and products of the earth, as opposed to humans or human creations. However this simply states that nature and humans are opposites, and one opposes the other. The poems I have chosen question this definition of nature and put it to humankind to answer the question, are we one with nature, or merely manipulating it to our own advantage, giving little back to our heritage? Oscar Wilde’s ‘The Ballad of Reading Gaol’ explores our own humanity and how easily two conflicting emotions become each other; whilst Charlotte Mew’s ‘The Trees Are Down’ examines human ignorance and through use of language she unravels the ever changing connections with nature. However it is Lawrence’s ‘The Snake’ that uses strong imagery to portray humankind in all its shapes and forms, forever changing. These three poems utilize a series of techniques that bring forth a common phrase we are what we hate, kill and love, which ultimately contributes to a universal relevance, the main idea I will be focusing on, ‘each man kills the thing he loves’. Oscar Wilde is considered a gifted author, playwright and poet of the nineteenth century. He was intimately involved in the up rise of aestheticism, a philosophy of nature and expression of beauty; Wilde expanded the narrow-mindedness of the Victorian Era, ultimately bringing a new light to society. ‘The Picture of Dorian Gray’, a semi autobiography, is considered the most seminal and serious of all Wilde’s works. However it is after being accused of homosexual offences, by his lover’s father, and further incarcerated at Reading Gaol that Wilde’s writing took a more melancholic approach. After serving his two years of hard labour, Wilde then moved to France, and was in ‘penniless exile’ It was in his last remaining years that Wilde produced two extremely heart felt pieces of work; De Profundis, a Latin term for ‘from the depths’, was an epistle addressed to his lover, Lord Alfred Douglas, and recounted his lifestyle of extravagance and love, within the first half. In the second part the text looks into his recent experiences, during his time at Reading Gaol, as he comes to terms with his spirituality. The other, ‘The Ballad of Reading Gaol’, a six ‘cantos’ poem, further subdivided into six lined stanzas, describes his experiences of loneliness and death, whilst incarcerated at Reading Gaol. The initial scene of the ballad, ‘He walked amongst the Trial Men, In a suit of shabby grey’, was inspired by the hanging of Charles Thomas Wooldridge, on Saturday 7th July 1896, a thirty year-old man convicted of cutting the throat of his wife. Charlotte Mew was an understated poet, whose works were less recognised, in comparison to Wilde, however she was highly praised by the likes of Siegfried Sassoon and Virginia Woolf. Mew lived a traumatic life, from beginning to end; facing close family deaths and two of her siblings being diagnosed with mental illness. These early experiences affected her future and had major influences on her; beginning with her and her sister Anne making a pact never to marry, in fear of passing on her family’s madness. Additionally Mew had similar sexual orientations as Wilde, attracted to ones own sex, however due to the condemnation of homosexuality, in the nineteenth century, Mew was left with a strong sense of suppression. Her life was extremely stifled by such experiences of death, loneliness and disillusionment and hence reflects these themes within her work. ‘The Trees are Down’ is a six stanza poem, that follows no structured form, merely ranging from one to nine lines, each stanza. The poem is based around the Revelation reference, at the beginning of poem: ‘-and he cries with a loud voice: hurt not the earth, neither the sea, nor the trees† and relates this to our society, past, present and future. David Herbert Lawrence, D. H.  Lawrence, was an extremely successful writer and artist. Publishing many plays, novels and volumes of poetry. He lived a very modest life, born in the small mining township of Eastwood, England, in 1885. Lawrence was an outcast, with few friends at school, who didn’t follow in his father’s footsteps of becoming a miner. So Lawrence went on to study, gaining a scholarship at Nottingham High School and then becoming an elementary teacher. However it was after falling in love with his old professor, Earnest Weekely’s, wife, Frieda von Richthofen, that his life was altered. Breaking off his engagement and ending his teaching career, Lawrence developed his writing into a career. ‘Sons and Lovers’ is a semi-autobiographical account of Lawrence’s experiences as a boy, under the name of Paul Morel, who loved his mother and full of hatred for his father. Lawrence wrote this novel after the death of his mother, in 1910, and explores the love of a mother â€Å"As her sons grow up she selects them as lovers–first the eldest, then the second. These sons are urged into life by their reciprocal love of their mother–urged on and on. † All three poets lived extremely different lifestyles, however the common thread between them is the literary period they lived in, the nineteenth century. Wilde’s work, pre-incarceration, was considered extremely lush and light, however post-incarceration it grew sad and he adapted Dark Romanticism into his works. Mew explored Naturalism where the environment controls people, especially in ‘The Trees are Down’, which is similar to the works of Lawrence who combines naturalism with Pre-Raphaelitism, combining literacy with the visual arts, which is seen through his strong imagery. Comparing these three literary movements helps shape each poem, providing a purpose behind the theme of each text. The intent of these poems differ slightly from one another, however all three have embedded the allegory of killing our intimates within their texts. Wilde takes his own personal experiences of loss, and additionally the example of Wooldridge’s own act, to reveal how within love echoes hate and vice versa. Mew, who’s poem seems completely ahead of her time, exposes the ignorance of the human race. This exposure of human’s prejudice towards nature is again echoed within Lawrence’s poem through the line ‘my education said†¦ he must be killed’. The common purpose within these texts is the exposure of human’s ignorance and how inevitable it is. Lord Alfred Douglas’s father took Wilde to court for alleged homosexuality and this life altering moment in Wilde’s life is easily identified within the poem ‘The Ballad of Reading Gaol’. However Wilde carefully entwines Wooldridge’s own attempt of ‘killing the thing he loved’ within his own story to expose the wider occurrence of this tragedy. It is questioned whether or not Wilde came up with this statement or whether it is a nod to Shakespeare’s Merchant of Venice when Bassanio asks ‘Do all men kill the things they do not love? ’ Wilde is well known for his stimulating epigrams, yet this phrase seems to generate a metaphor for life and although not a question, like in Merchant of Venice, Wilde questions the similarities of love and hatred. When searching the word ‘love’ up on Thesaurus. com it provides a list of antonyms, including ‘hatred’, and vice-versa and yet here we see Wilde placing the two, opposing verbs, hand in hand. Wilde’s underlying purpose within ‘The Ballad of Reading Gaol’ is not to recount his experiences at Reading, but what Wilde is really looking for is the mode of interaction in which love and hatred are one and indivisible, in which the bitterness is an expression of the admiration. Written in the nineteenth century Mew’s poem, ‘The Trees are Down’, was completely ahead of its time and in today’s society is seen as an empowering demonstration of humanity’s destructive ignorance. Using the line from the revelation Mew makes deep connections with the past and by examining her present looks into the future of what is to come, what is now extremely relevant. The purpose of this is to reveal society’s destructive nature and speak out against the destruction of our heritage as ‘half my life it has beat with’. Lawrence examines prejudices of the human race towards animals, within the poem, ‘The Snake’, and how we accept the words fed to us in an alleged ‘education’. However the irony of it all is that we are one with the Snake and this is what Lawrence was trying to achieve. Describing the snake drinking from trough as if ‘he’ is a person, the same as the narrator, then ‘he’ looks up ‘just like cattle do’. Lawrence’s connections across the animal kingdom; man, snake and cattle alike, break down the barriers of humans vs. animals, generating a scene of equality. However it is once the narrator’s ‘voice of†¦ education’ convinces him otherwise, his face becomes humanity; fearful and paranoid. Each text focuses on humanity and from here branches off the love-hate, ignorance and prejudices of the human race. Wilde highlights the correlations between love and hatred we express towards one another, Mew exemplifies humanity losing touch with their heritage, whilst Lawrence’s reveals the irony within humankind’s prejudices. In all three cases the writer is attempting to exemplify how two effects, wildly different, grow closer together, reciprocating off one another, or how two objects, scientifically/emotionally tied together can push one another away.

How It Feels to Be Colored Me †Arguement Essay

In â€Å"How it Feels To Be Colored Me†, Zora Neale Hurston presents her attitude about racism while growing up as an African American. Hurston’s views are very similar to Dr. Martin Luther King jr.’s. When talking about racism, she uses her heritage to help present her attitude. Her feelings toward the white folk aren’t hostile, but they aren’t exactly agreeing either. Hurston’s views are like those of Dr. Martin Luther King jr.’s. Both of them acknowledge that they are different than everyone else around them. They are an individual. They don’t agree that they should fit in and be the normal, African American. Both overcome hard times and discrimination and had successful parts of their careers. Hurston uses her heritage to discuss her views on racism. She grew up in a town full of blacks, so she was basically the same as her neighbor. She says she never felt colored until her family moved to Jacksonville. Then, she was constantly reminded how she was the descendant of slaves. She tells about how she was always so alone. She also discusses how she escapes the prejudiceness and gets away by going to listen to music, though; some white folks come in and make conversations with them. She speaks about her feelings towards the white folks. Hurston talks about how â€Å"among a thousand white persons, I am a dark rock†, she feels as though she is different, and she sticks out. She speaks about how she is her, she has no race. Though, she also doesn’t understand how someone could be so prejudiced against someone’s skin color. She makes a point of how they get along Hurston presents her views in a very understandable way. She speaks about how she feels about the white folk. She uses her heritage to help her deal with racism. Her views are almost the same as Dr. King’s. I feel the same way Ms. Hurston does about Racism..

Acesite Corporation vs. Nlrc

Acesite Corporation vs. NLRC Facts: * Leo A. Gonzales (Gonzales) was a Chief of Security of Acesite Corporation. * Gonzales took several leaves (sick leave, emergency leave, and vacation leave), thereby using up all leaves that he was entitled for the year. * Before the expiration of his 12-day vacation leave, Gonzales filed an application for emergency leave for 10 days commencing on April 30 up to May 13, 1998. The application was not, however, approved. * He received a telegram informing him of the disapproval and asking him to report back for work on April 30, 1998.However Gonzales did not report for work on the said date. * On May 5, 1998, Acesite sent him a final telegram in his provincial address containing in order for Gonzales to report back to work. * Gonzales, who claims to have received the May 5, 1998 telegram only in the afternoon of May 7, 1998, immediately repaired back to Manila on May 8, 1998 only to be â€Å"humiliatingly and ignominiously barred by the guard (a s ubordinate of [Gonzales]) from entering the premises. * It appears that on May 7, 1998, the issued notice of termination was thru an inter-office memo. * Gonzales thus filed on May 27, 1998 a complaint against Acesite for illegal dismissal with prayer for reinstatement and payment of full backwages, etc. * Acesite claims, Gonzales â€Å"showed no respect for the lawful orders for him to report back to work and repeatedly ignored all telegrams sent to him,† and it merely exercised its legal right to dismiss him under the House Code of Discipline. LA – the complaint for lack of merit, its holding that Gonzales was dismissed for just cause and was not denied of due process. * NLRC – reversed that of the Labor Arbiter. * CA – finding that Gonzales was illegally dismissed, affirmed with modification the NLRC decision. Issue: * WON Gonzales was legally dismissed for just cause. Held: * No. there appears to have been no just cause to dismiss Gonzales from employ ment.As correctly ruled by the Court of Appeals, Gonzales cannot be considered to have willfully disobeyed his employer. Willful disobedience entails the concurrence of at least two (2) requisites: the employee’s assailed conduct has been willful or intentional, the willfulness being characterized by a â€Å"wrongful and perverse attitude;† and the order violated must have been reasonable, lawful, made known to the employee and must pertain to the duties which he had been engaged to discharge. In Gonzales’ case, his assailed conduct has not been shown to have been characterized by a perverse attitude, hence, the first requisite is wanting. His receipt of the telegram disapproving his application for emergency leave starting April 30, 1998 has not been shown. And it cannot be said that he disobeyed the May 5, 1998 telegram since he received it only on May 7, 1998. On the contrary, that he immediately hied back to Manila upon receipt thereof negates a perverse att itude.

Politeness Theory by Brown & Levinson Essay Example | Topics and Well Written Essays - 750 words

Politeness Theory by Brown & Levinson - Essay Example Everyone has a genuine face and a face with the mask. While speaking to someone you go by pretentions, depending upon your estimate of the nature of the individual. Smart sales personnel in a departmental store frame their own definitions and strategies while dealing with the customers. But impolite disposition should not be a rule but an exception. Howsoever powerful may the waves of the ocean, their real nature is mere water! Similarly man’s real nature is politeness. Impoliteness is the hallmark. Polite and impolite also need to be understood in the linguistic, cultural and ethnic contexts. Culture impacts our way of expression. Word meanings and their implications in a particular context are different.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   My real life examples as to how politeness saved the situation   Ã‚  Ã‚  Ã‚   Politeness is peace-giving. Politeness needs to be tempered with humor in critical situations. It is not the trait of the weakling. It is an asset of the strong! â€Å"Silence is the sweetest sound on Earth,† said Mr. Boris Pasternak, the famous Russian author. I politely disagree and desire to give some examples from my own life, why and how I was obliged to break the barrier of silence to defend myself without offending the individual in front of me. In one of the arguments in the shopping mall when I was making desperate attempts to restrict the possible cut on my credit card, and requesting my wife to put a break to the shopping spree, she challenged me to ask, â€Å"Do you always think that whatever you say is correct?†

Against The Odds - Documented Argument Essay Example | Topics and Well Written Essays - 500 words

Against The Odds - Documented Argument - Essay Example Further, my above average intelligence greatly tilts the statistical output towards my getting high academic grades. Consequently, I will fall within the Shapiro et al research findings’ possible 15 % of students who can complete their four year college degree within six long fruitful years (Shapiro et al. 9). My intelligence will lead to my being among the 42 percent of students who are able to complete their college degrees without need to transfer to another institution (Shapiro et al. 4). The statistics espouse the responsible students can pass all college requirements. Furthermore, my allocating enough time to studying my class lessons contributes to my being one of the few successful college graduates. Consequently, my being part of the 51 percent mixed students enrolled in the average college program will help me gain much needed support from diverse student friends. The mixed student group is composed of both full time and part time student enrollees (Shapiro et al. 18). Moreover, my long list of easily retrievable relevant academic resources ensures I can submit high quality academic papers on time. Consequently, I can finish my college course within six or less years. My close kinship with the college library staff and other intelligent classmates will assure my falling within the statistical finding’s less than 35 percent student population who will receive a college diploma within six years (Radford et al. 13). The statistics affirm that the effective and efficient students will graduate from college. In addition, an interview with one my close associate affirms I will successfully grab my college diploma. The interviewee shared statistics to back up the college claim (U.S Census Bureau 1). The statistics state that there is an overall 30 increase in the number of college graduates from 1965 to 2010. Specifically,

Summary Essay Example | Topics and Well Written Essays - 250 words - 77

Summary - Essay Example The Gallop Poll of 2011 shows just 26% for handgun ban. The issue with the thinkers is whether gun control can stop tendencies for violence. Whereas the arguments and counterarguments continue amongst various bodies concerned with controlling gun and violence, the measure does not get the legal support. â€Å"With a 5-4 decision in the District of Columbia v. Heller case heard by the Supreme Court in 2008, the court’s new reading of the Second Amendment indicates that handguns cannot be banned even at the local level because there is an individual right to handguns in the home for self-defense.†(Ryan, n. p.) This seals the issue in favor of keeping the handguns. The other method suggested is health screening of the people and the background check from the â€Å"federally licensed dealers.†(Ryan, n.p.) This suggestion is good in theory but its implementation is not practicable. One can easily buy the â€Å"gun from a private seller.†(Ryan, n. p.) But the suggestion to ban AR-15 type assault rifles merits consideration, as these types of weapons have role for civilian purposes. Congress did ban 9 types of semi-automatic weapons in 1994 and the â€Å"ban expired in 2004 and was not renewed.†(Ryan, n.p.) Going by the General Survey there is a marked reduction in gun related crimes all over the country in the last 40 years. But the Church is deeply concerned about gun trafficking and suggests that the members of the community should exercise moral authority to educate the people about the gun culture and finally guns should have no place in a society governed on moral principles. The faith community has the responsible and c onstructive role to play in this

E-commerce in the life of Qatari Women Research Paper

E-commerce in the life of Qatari Women - Research Paper Example From the perspective of a business, IT allowed companies to operate online and reach global customers at the most cost efficient way. One of the dimensions of IT is e-commerce and it acts as a tool that facilitates online business. In addition, it has also helped customers to carry out online purchases irrespective of the time and geographic location. The negative factors on the other hand appeared in the form of security threats. Before getting further deeper into the study, a brief overview of e-commerce is presented below. The notion of e-commerce can be traced back during the epoch when the concept of the internet just came into light. During the earlier days, e-commerce was deemed as the process through which companies used to carry out their transaction over the electronic platforms (Majumdar, Cave, and Vogelsang, 2005). During this period, the concept of Electronic Data Interchange (EDI) and Electronic Funds Transfer (EFT) has also emerged and companies used these tools to tra nsact in an efficient manner. These technologies have allowed companies to complete transactions electronically and companies were hugely benefitted by it. However, the commercialization of e-commerce only became possible during the early 1990s and as soon as it became commercialized a number of business houses such as eBay and amazon.com have taken their business online (Reynolds, 2004). In the early stages, companies had shown more interest in using the internet as a tool for promoting the business, but for the last decade it companies became more active in selling their products and services over the online platforms (eCommerce-Lund, 2004). From the point of view of customers, e-commerce eased several kinds of activities. For example, it allowed customers to shop during their convenient time and also allowed them to carry out shopping sitting inside the home (Bhasker, 2006). The sales figures also experienced huge growth. According to reports, the growth was around 32% in 2012, i n comparison to 2011 (Provost, 2012). Apart from e-shopping, e-commerce also allowed customers to carry out banking transactions. Hence, it is evident that e-commerce now acts as part and parcel of the life of human beings. Executive Summary This study seeks to shed light on the impact of e-commerce in the life of Qatari Women. The primary objective was to identify the problems faced by Qatari women in using e-commerce in their daily life. In order to address the objectives, the study will carry out a survey of 10 people so as to know their perception about e-commerce. In order to analyze the findings, the study used qualitative approach. Both primary and secondary research was undertaken to identify the problems associated with e-commerce in the life of Qatari women. The key findings of the study were that Qatari women face problems related to the payment gateway, security issues, delivery issues and issues pertaining to terms and condition. In order to triumph over these issues, t he Qatari women should make themselves more familiar with such platforms and should only use authentic platforms. Similarly, the government must ensure that the websites are transparent enough and is offering secure payment gateways. The Problem The women of Qatar exercise full right so as to take a proactive role in the society and simultaneously act as a vital element in the development process of the country. With the modernization of the society, the Qatari women have also adopted themselves with the shifting market dynamics (qatarembassy,

Whole Food Market Essay Example | Topics and Well Written Essays - 1500 words

Whole Food Market - Essay Example These two are then measured through the company’s financial performance. Identification of issues Whole Foods Market with its vision to become an international brand for natural and organic foods is also committed to become the best retailer in its community wherever it is located. In line with this, the company seeks to give significant higher value for its customers. This is evident in its core values in which there are two important points that are in line with quality of its products and giving the best for their customers (Whole Foods Market 6). Part of its core values is to sell highest quality natural and organic products available. Then there is a great detail of satisfying and delighting their customers. These are just some of the important values that they need to ensure in order to continue live and satisfy their vision. In the midst of this effort to focus on its vision, there are of course strategic issues that need to be taken into consideration. One of its essen tial goals in order to achieve its corporate goals is to continue grow its revenue. Furthermore, Whole Foods Market is also concern in educating the market with its significant definition about the quality of its product and service offerings. Thus, there are three essential issues that need to be understood at this point. The first issue is about its strategic move to highly differentiate its product and service offerings. The next significant issue is about understanding its customers and feeding them with the right information. Finally, the next consideration is its ultimate measure of success which the bottom line is to look closely at its revenue and generated profit. Analysis of issues Product and service differentiation There is a clear emphasis of this issue based on the vision of Whole Foods Market. In the first place, the Whole Foods Market is significantly trying to be a cut above the other by creating relevant changes in its service and product offerings. From its vision , it wants to become an international icon for natural and organic foods. Thus, as retailer it aims to give something new to its customers. However, it is not just enough to create something new for the customers, but there is a need to ensure a need for them. In other words, prior to providing something better in the market, Whole Foods Market should ensure that it has understood the prevailing demand or need of the customers. In the first place, there is going to be a challenge on the part of Whole Foods Market because it has to clearly define beforehand what natural and organic foods are all about. This is going to take enough of its time because customers need to be widely educated or well informed about its product offerings. In this level, the Whole Foods Market is trying to create a need for its product offerings in a way that there is a significant move to educate its customers. In today’s marketing activity, companies or organizations are able to successfully create a need for their product offerings. In fact, this is the basic and most common trend for them to be able to gain a high market share. Correspondingly, the Whole Foods Market needs to successfully create a need for its service or product offerings in order to successfully employ its product differentiation strategy. In this strategy, in order for it to be effective, the Whole Foods Market should try to promote products that matters to the customers. In other words, it is important that the needs of customers should be properly addressed. Fortunately, the Whole Foods Market is trying to establish a way to improve its customer service in the event of product assistance. It opens up its

Customer insight project Research Paper Example | Topics and Well Written Essays - 2500 words

Customer insight project - Research Paper Example Marks & Spencer (M&S) has been providing clothing, home products and food products to customers for over ten years (Wood & Finch, 2009). This period necessitates continued understanding of the customers’ loyalty and how to improve the weak areas. Understanding customers loyalty is crucial to the business management as it assist the management in decision-making (Stafford, 2009; Chislett, 2009; Willsher, 2011). A marketing research was carried out to assess the degree of customers loyalty. The research was strategic with the goals of providing information needed to remain at the top in the market. It was expected to give insights of the customers that could be used by the business manager to improve the business market power. This work reports findings from the marketing research conducted. The aim of the study was to understand and improve customer loyalty for Marks & Spencer (M&S) on the service delivery and products offered. In meeting the goal of the research, the study seeks to answer the question "how do services and product quality offered enhance customer loyalty for Marks & Spencer†? The core goal of the study was to understand customer’s loyalty and how to improve the degree even further in regard to Marks & Spencer products. The study proposes the following specific objectives. This study was a qualitative market research executed through a market survey. Semi-structured questionnaires were administered to the selected respondents through face-to-face interviews between them and the trained enumerators. The above ensures collection of accurate data from the respondents interviewed (Saunders, Lewis & Thornhill, 2012). Questionnaires with Likert scale scales employed with the aim of quantifying how product and service provision enhances customer loyalty in regard to Marks & Spencer. The questionnaire included an introductory section, a detailed description of Mark & Spencer and the aim of the study. The questionnaire also

A World of Art Essay Example | Topics and Well Written Essays - 1250 words - 1

A World of Art - Essay Example The other the triangle between Mary and Jesus represents the cup of the last grail. Look out the windows, one can see the country side which is not congruent with the subject matter. He uses the technique of Chiaroscuro. It is dark in the room and bright outside. It is interesting to note that he used the same country side in his Mona Lisa painting which he completed in 1503. The colors used are green and orange(brown). There is symmetry with the large rolls on the table. Important paintings Perspectival study of the Adoration of the Magi: (Art Authority) Pen and ink, traces of silver point and white on paper. Fascinating to see his study in perspective of texture, the use of Chiaroscuro, the use of sienna to show white, the three dimensional by the fact that we can see the thickness of the stairs and the pillars. the lines showing how everything is done in perfect mathematical dimensions then The Adoration of the Magi: (Art Authority) oil on panel. The oil thing which remains from t he perspective is the stairs and the pillars but they are quite distant. It was as though he used the study to do several painting. The texture is very primitive for a Leonardo da Vinci. The trees are two dimensional and Mary is in one color. Perhaps it is a question of aging. The people are half real. Titian, The Assumption of the Virgin: Oil on wood. A perfect study in vertical perception there is an incredible sense of movement, towards the heavens. In analyzing the lines, there are the two triangles with two parallel lines. The texture of the fluffiness of the clouds but also the heaviness the angles have of carrying Mary Profane Love: a perfect contract between the Assumption and this perfect technique of Chiaroscuro. There is the light shining on her face and her hand. She is also looking at someone but we do not see him either. There is also the mirror which shows you something that the person in the painting doesn't see. This is a technique which began with Leonardo da Vinci . The texture of her clothes is magnificence Van Gogh, Starry Night : oil on canvas. It is not polychromatic though he does use a great deal of blue. He avoided using red. He uses hatching in the modern sense of the word. His brush makes short rapid strokes of the same color. The texture has very little dimension to it other than a little bit of the town. I would not call it two dimensional. Road with Pollarded Willows and A Man with a Broom (Art Authority) is from carbon, ink, and watercolor on paper. His texture is three dimensional. You can see the end of the road but you see the beginning of the impressionist school as the road slightly bends to the right. As he advanced in his training, he mixed different techniques each time of pencil and ink, or pencil, ink and water color to cite an example. He showed his being influenced from different schools. He painted 37 self portraits. It is documents that none of them look directly at the viewer but the Self Portrait 1887 looks straig ht on. His self portrait in the straw hat looks like a modern version of hatching. Jasper Johns, Numbers in Color: uses the technique of pattern and polychromatic. He called his paintings of clusters "crosshatchings (Johns) Grey numbers (Art Authority) is the same technique of patter without color Andrea Mantegna, The Lamentation over The Dead Christ 1494: tempera on canvas. The texture is three dimensional. He uses lines in one angle to gain depth to take away from the size of his feet. There is

Ethics and Islam Essay Example for Free

Ethics and Islam Essay The interpretation of secular vs. religious ethics is always interesting, when we try to understand which of the two deserve our support. Obviously, both ethical philosophies have the right to exist among us, but the provisions of the religious ethics in Said Nursi’s vision are not only unique, but are sometimes surprising, and are sometimes unacceptable to those, who keep to secular ethical traditions. Said Nursi insists on ethics having religious foundations. His ethical vision is based on the assumption that religion is the source of reliable ethical knowledge. â€Å"For Nursi, the ultimate source of all ethical reflection is the Qur’an† (Markham 69). In this situation it is possible to suggest that Qur’an should be simple and understandable to the common people, so that they should be able to follow its provisions. The assumption is rather debatable: on the one hand, there seems to be nothing negative or threatening in the fact that Said Nursi keeps to religious foundations of ethics. On the other hand, I may suggest that those who refuse to accept the life of the prophet Muhammad as the source of ethical knowledge, risk facing opposition from religious ethics’ supporters. This ethics loses its relevance as soon as it is faced with the fact that there are possible other sources of ethics in other cultures of the world. Moreover, and I would agree with Markham, in that there is no guarantee that being obedient to Qur’an means seeing its wisdom; in case we do not understand the provisions to which we should keep in our ethics, it loses its relevance and meaning. The strong side of religious ethics in Said Nursi’s words is in accepting violence as weakness in trying to resolve various disputes. â€Å"Nursi is committed to handling disagreement with peaceful means not because he shared a western skepticism about the truth of religion, but because of the truth of religion† (Markham 72). Secular ethics would easily reject these religious attitudes. While Nursi tries to justify the strength of religion, he obviously forgets that this strength is relevant only within the limited religious circles. Secularism exists and cannot be denied. For those who consider themselves being secular the strength of religion is closely connected with the power of metaphysical phenomenon. In the absence of the latter, the power of the former becomes debatable. Thus, religious foundations of ethics can be applied within the limited space of extremely religious eastern countries, which keep to Islamic religion. Especially interesting is Nursi’s ideas about personal ethics and social equality. His interpretation of a person in illness is rather curious, though is also natural within the eastern religious framework. â€Å"O ill person who lacks patience! Be patient, indeed, offer thanks! Your illness may transform each of the minutes of your life into the equivalent of an hour’s worship† (Makrham 74). The question is whether patience is equal to inactivity. Recognizing the religious value of pain and suffering is what Nursi tried to convey in his ethical teaching (Markham 75) but this also risks confusing ethics with religion, without creating any distinct border between them. Social ethics in Nursi’s vision tends to support equality through rejecting interest and recognizing the importance of redistribution. In these terms, Nursi seems to reject the pluralism of social status in the society. Moreover, rejection of interest is closer to rejecting secularism, than to supporting religious foundations of ethics. Conclusion The whole ethical theory created by Nursi deserves attention but seems to be founded on the grounds, which do not justify the strength of religion but better protect it from the intervention of the external knowledge. In this light religious ethics seems even more vulnerable, than Nursi tried to represent it. Works cited Markham, I. â€Å"Secular or Religious Foundations for Ethics: A Case Study of Bediuzzaman Said Nursi†. In I. Markham I. Ozdemir, Globalization, Ethics and Islam, Ashgate Publishing, 2005, pp. 65-78.

Dating Methods Essay Example for Free

Dating Methods Essay For example, pollen, bone, hair, parchment, wood, charcoal etc. | 400-50000 years old. | Principal that all living things interact constantly with the atmosphere and we absorb Carbon 14, however at the point of death, living creatures stop absorbing carbon 14, and the carbon 14 is frozen. This carbon decays at a known, constant rate. AMS DATING (Acceleration, Mass, spectrometry)| Organic Materials| From 400-70000 years old. | Quicker results, much more expensive. Also more accurate, less samples needed and less possibility of contamination. | TREE-RING DATING (DENDROCHRONOLOGY)|. Trees or any timber object made from trees. | | Counted by looking at a cross section of the tree, looking at how many rings, the ring on the inner most centre is the first growth, and the outside ring is the last. THERMOLUMINESCENCE| Pottery| Over 50000+| When deducing if an artefact is fake, they can turn to Thermo luminescence to deduce weather it is real. Other time, in the form of energy, electrons will be stored within it, and if you heat the object to 500 degrees. Celsius or more, and then there is a flash of light which can be measured to see the age. | POTASSIUM ARGON DATING| Volcanic Rock| Up to millions of years. One of the most useful for dating human evolution. Used to date fossils. | DNA TESTING| | Has no age limit, can be used as long as DNA is available. | Shows the blueprint of an organism, is within all living or dead creatures. Useful in all matter to do with any remains, can tell us significant information. | URANIUM SERIES DATING| Roick including Calcium | 50000 – 500000 years old| Also useful for dating human evolution. |

The Recording Of Lets Dance By David Bowie Music Essay

The Recording Of Lets Dance By David Bowie Music Essay He produced it and plays all rhythm guitar sections. Stevie Ray Vaughn recorded the guitar solo. He said in an interview that he sat in a corner and waited for his cue then added an improvised Albert King style solo. All in one take. This songs lyrical message is simple but David usually has a more complex character and this song seems to be a bit out of his style. That is why the song is not appreciated by a lot of Bowies fans. I see it as Bowies way of getting out of his skin, »Ã‚ ¿ letting his spirit run free forgetting all that holds up back to thinking with clarity. Bowie said that it was one of his lowest periods as an artist, although Stevie Ray Vaughn was credited on the album he wasnt still that famous and after that he became internationally famous with his own album. Bowie admits that this wasnt his best period creative wise but great at the time. Reinventing himself as an 80s pop icon was the kiss of death on his imitators such as David Sylvian, yet in truth the 2 becam e even more alike. It was almost like Bowie was playing him at his own game. LetHYPERLINK http://en.wikipedia.org/wiki/Lets_Dance_(David_Bowie_album)HYPERLINK http://en.wikipedia.org/wiki/Lets_Dance_(David_Bowie_album)s Dance was released as the first single from the album with the same title in 1983, and become one of his most successful records during that underrated part of his creative work. Bowies approach to the song and lyrics seems different compared to previous albums. The song is simple, but polished not neccesarily following the true image of Bowie in the seventies. The single was the fastest selling in Bowies career. It entered the UK single charts at number five and two weeks later the song stayed in top of the charts for a period of three weeks. That was Bowies only song to reach number one on the two sides of the Atlantic Ocean. It narrowly missed topping the australian charts, peaking at number two. Lets dance was the fourth best selling single in 1983. Lets Dance helped Bowie to find a new younger audiences, unaware of his past career in the 1970s. The piece was one of the most played on the Serious Moonlight Tour (the name came in from the lyrics in lets dance I have been using the studio version for the analysis which is approximately seven minutes and thirty eight seconds. There is an edit of that version for the single release of the track, which is shorter in length 4:10. The song was recorded and produced by Nile Rodgers. He had a strong influence on the song and was working with his band Chic at that time. Lets Dance was the most commercial product in the album according to Bowie. Thats why it was also chosen for title of the album. It represents his best work from that time. Almost like it was written to remind the public that hes still writing quality, in fashion music. He wanted to be famous and he achieved it once again. The song was designed to appeal to young generations at the time, but still he managed to combine the disco with his own style and that makes it harder. Nowadays the typical mainstream artists such as Lady GaGa appear to be a bit monotonous compared to Bowies work. All of her songs that are mostly played by drum machine and a single DJ. The usage of a DJ limits the improvisation in a piece, because that way you have everything controlled by a single person that has to do all the work. Theres a strong element of electronic instruments and sequencers involved in the production. Even on her live performances shes doesnt use real musicians and the music is played by a single DJ usually. It feels like its missing the human feel compared to Bowies art. Lady gagas music seems a bit narrow in terms of improvisations and experimenting with harmonies and melodies. She also tried to use the same dance clichà © with a song with the title Just Dance. In an interview she admits that she was influenced by Bowie who spent the majority of his early career pretending that he came to this planet from outer space. Gaga has been sporting a collection of shiny suits made popular by Bowies alter-ego Ziggy Stardust. Gaga once said Fashion is everything to me in contrast with her Bowie oversaw the downsides and benefits of using digital instruments, but he remained true in his nature. He changed, but while listening is easy to distinguish his version of Lets Dance to the one by Lady Gaga which is not that unique. They are both similar in the whole dance approach to the piece, but musically Bowies delivers a lot more musical content with regards to the solo of Steve Ray Voughn whos still a legend today. Bowies art is evergreen it should last for a long time and its not just the music that makes it. Its the whole approach to it, the makeup and the drama he makes. Twenty years later his music is still relevant to whats going on nowadays. As in the music video there are still many third world poor people. And the dance music still dictates the commercial industries. The Disco became mainstream or popular in 1978-80 Its roots are coming from the jazz, classical and soul music. At first the music was in support of the rights movements and homosexual people. There was major revolution in a musical cultural and ethical form in that pre nineteen eighties pop. One of the first underground dance genres was strongly influenced by chic. Similar to the way that Blues, Jazz and Soul were used as a platform for a cultural revolution the disco was mainly exploited by black people in the beginning until it became popular. Chic dominated the charts for several y ears with a series of carefully crafted songs, including Le Freak and Good Times. Before long, other artists were turning to Rodgers and Edwards for their production, arranging, and songwriting skills, resulting in massive hits like Sister Sledges We are Family. In 1979, Rodgers brought his magic touch to David Bowies Lets Dance and a few years later he hit solid gold, producing Madonnas landmark singles Like a Virgin and Material Girl. He later continued to work with a diverse crop of famous artists, including Jeff Beck, Eric Clapton, Mick Jagger, Duran Duran, David Lee Roth, INXS, Grace Jones, and even jazz legend Al Jarreau. Nowadays Rodgers heads up his own label and production company, as well as Sumthing Distribution, a national record distribution company. The song was produced mimic early dance production in the eighties, although recorded with acoustic instruments the gated drums and the delay effect on almost everything suggest that song was intended to recreate the atmosphere of the new decade. Nile Rodgers is known to use drum machines in most of his productions, even though the groove of the band is more important to him as a producer. The groove has to be right before the start of overdubbing. He never used a metronome in Chics records even thou they were supposed to be a dance band. Years later he developed that technique. Theres a melody in the bass that was performed by Carmine Rojas who is known for working for Rod Stewart as a bass player and also a music director. During his time with David Bowie he was one of the most respected bass players in the industry. He was introduced to Bowie by drummer Tony Thompson. Carmine and Tony knew met when they were playing together in Labelle. In 1986 Carmine worked as a studio musician on a song recording for Alphavilles album Afternoons in Utopia. The bass seems to be a bit artificial like it was double tracked with a synthesizer. Thumping the bass in that way gives it more character to sustain the beats typical for many records in that era. Theres also a guitar in these first eight bars that was performed by the producer Nile Rodgers. He was a producer and a guitar player at the same time. He first began his career as a session musician living in New York he had the opportunity to play at the famous Apollo theater on one stage with the likes of Screaming Jay Hawkins, Maxine Brown, Aretha Franklin, Ben E. King, Betty Wright, Earl Lewis and the Channels, Parliament Funkadelic. Later in the seventies he met bassist Bernard Edwards. Together they formed a band called the big apple band. They made a huge success with a single hit, which allowed them to tour and even an opening for the Jackson five on their first tour in 1973. The band was disbanded after the second album failed to reach enough popularity to provoke enough sales, but Rodgers and Edward didnt give up and joined the drummer Tony Thompson. With his influence in the band they recorded as a Funk-Rock band called The Boys, which played many gigs on the East Coast. Despite the huge interest from the labels to sign them they didnt have any luck just because they were black. There was a concern that the black artists were too hard to promote. The band was playing at the local pubs at that time. Another New York artist, Walter Murphy, had a band also called The Big Apple Band and Rodgers and Edwards were decided to change the band name to avoid confusion in the public. In 1977 the band changed their name to Chic. They begun recording material with back vocalist Luther Vandross mainly disco tracks. Their success later helped the disco become popular, two of their most popular songs were called Everybody Dance and Dance, Dance, Dance I think David Bowie thought of the song as a clichà © to what became popular since his last album. Compared to his old songs such as Space oddity (1969) Life on mars (1973) that changed peoples lives and influenced revolutions. Althought David Bowies frequent changes of image, direction and carrer have been written about and discussed to the point of saturation, his songs are often overlooked. For instance Space Odity, released in 1969 to coincide with the US landing on the moon was his first major hit. Bowies fascination with space figures frequently in his early carreer. After abouncing he was gay, he reinvented himself from hippy singer-songwriter into Ziggy Stardust full on glam rocker from another planet. With the same unusual combinations he used Lets Dance as a clichà © for that period of time and how the trends were changed. He wanted that to work with musicians of Chics class, because they were the godfathers of the disco that was pretty popular at the time. Most of their records have a similar feel of the bass line being chopped to eights and sixteenths in 4/4 in tempo. Although the line is in short rhythmical dura tions still theres a pulsing downbeat every crotchet, just like on modern underground dance music. The music tended to layer soaring, often-reverberated vocals, which are often doubled by synthesizers. The use of wah pedaled effects that sounds like metallic scratches in short durations. Peculiar backing keyboard instruments such string synthesizers and electro acoustic keyboards such as the Fender Rhodes piano, Wurlitzer electric piano, and Hohner Clavinet. Synthesizers are also fairly common in disco, especially in the late 1970s. The rhythm was usually played by spectacular, syncopated basslines (with common use of octaves) played on a bass guitar double tracked with synthesizers. The drum part was played on acoustic drum kit, African/Latin percussion or electronic drum machines such as the Simmons and Roland drum modules. Although some of James Browns songs are strongly influenced by black people the disco it still remains heavily improvised on stage, but with the disco there wa s a new way to improvise live with the recently invented digital and analog pads and samplers implemented in the recent technology development. A shift in the audience from younger generations introduced the disco as a new type of funk mixed with analog synthesizers that could hold a sustained and controlled downbeat and without the need of a real drummer. The fixed beat technology developed enough with the help of drum machines to ease the process of live production holding a fixed tempo without a need of a drummer and at the same time sacrificing the musical content in it. The role of Nile Rodgers was to balance these two aspects. The song begins with a voice intro performed by Bowie which reminds of something from the sixties called layered seventh. In the first bar there is only one vocal which is the first tone in Eflat major, then in every new bar there is a new vocal layered, the third and the fifth until reaching the dominant seventh major and resolving to first at the fifth bar (0:09)Thats where the basics of the pre-verse are formed. After the intro the chord verse structure is changed with a tonal centre of Bflat7sus . Followed by a Eflatseventh in the second bar. Fsharp in a six chord in the third bar and Bflat minor sixth in the fourth. In instrumental intro which consists of eight bars trumpet solo in the beginning performed by Mac Gollehon. It can be characterized as a jazz improvisation. Bowies voice enters the verse, which consists of sixteen bars. Theres a wooden block played percussion instrument played in sixteenths, a stereo delay is also applied. Splitting the signal into a dry sound, which is panned to the right and the delayed sound is panned to the left. Theres a short saxophone melody played by Bowie at the end of every eight bars in the first verse. A big amount of delay was used on the lead voice; it bounces in far left and right. The rhythm guitar and snare seem to use the same technique with using a long delay time. And then it goes to the chorus section with the lyrical content: With the harmony change in A flat in the first bar that goes to C sharp major and Eflat major on the phrase run with you and its repeated again by the guitar and bass. The whole melody line is repeated once again. And then on my love it goes from Aflat major through F minor, C sharp and E flat. The end part of the chorus from and tremble like a flower Is in Eflat major seventh followed by a Bflat7suspended4, eflat major again Fsharp major six chord and the whole chorus ends on Bflat minor sixth. ABBA Dancing Queen (1976) Andy Gibb Shadow dancing 1978, (B)Anita Ward Ring my bell 1979, Barry White »Ã‚ ¿ Youre The First, The Last, My Everything (1974), Hot Chocolate You Sexy Thing (I Believe in Miracles) (1975), Lipps Inc Funky Town (1980), Sister Sledge We are family (1979),

Polar Bear :: essays research papers

SPECIES- Ursus Maritimus, Polar Bear, lord of the Arctic. Lives in an area of five million square miles of snow and ice. From Siberia to Alaska and across Canada, Greenland and the Islands north of Norway, he is the master of all living things except man. It lives in the brutal cold, ice, and snow. The temperature can plunge down frequently to -40 degrees and sometimes even lower but that does not bother the polar bear because of its color-less skin and layer of insulation fat. Its range extending around the northern polar region. Necessities of Life-The polar bear eats mostly seals which he has to hunt. His trick is to wait by a breathing in the ice and when a seal comes up by that breathing hole, he grabs it so fast it knocks it unconscious and then he eats it. Other pray is a walrus calf or a musk ox stuck in snow, birds, eggs, fish, and dead whales. And sometimes in the summer it eats berries and grass. The polar bear has no water to drink so it only eats the skin and blubber, avoiding the meat. So by eating the blubber and leaving the meat the male bear is helping keep his body in balance with the surrounding environment. The bear would usually stay in a den or bury it self in the snow to avoid the suns ultra violent rays. Usually the pregnant female polar bear stays in the den.Food Chain-The polar bear finds its way on the top of its food chain. No predator on earth approaches the bear in size. The polar bear towers over everything else in his food chain. The only thing that could stop him is a human with a gun.Super Amazing Facts-The polar bear is well adapted to its special live style. The hairs of its thick coat are hollow, giving extra insulation against the bitter arctic cold. It also has an extra layer of insulating fat under its skin and the hairs on the polar bear are color less, when the sun hits them they look white. Polar bears are twice as big as lions or tigers, a typical adult male weighs half a ton and is five feet high at the shoulder. His paws are a fool wide. When he stands up straight, he can look an elephant in the eye.Explain- My species was endangered bad back in 1965 with no more than 5,000 left in the world.

Borges Use of Berkeleys Idealism Essays -- Essays Papers

Borge's Use of Berkeley's Idealism Jorge Luis Borges drew upon a number of philosophical and intellectual models in his writing, one of which is George Berkeley’s subjective idealism. In "Tlà ¶n, Uqbar, Orbis Tertius," Borges paints a picture of a perfect reality governed by Berkeley’s idea that matter only exists in perception, and in "The Circular Ruins," he presents a man who creates a boy who cannot exist independent of his perception. However, by employing Berkeley’s logic in these stories, Borges is in fact denying Berkeley’s ultimate purpose: the justification of the existence of God. In almost all of his work, Berkeley’s fundamental goal is to logically disprove any thinking that presumes the non-existence of God (Muehlmann 231). In a nutshell, Berkeley argues that matter does not exist outside of human perception. In his Three Dialogues between Hylas and Philonous, he asserts the following: If it be allowed that no idea nor anything like an idea can exist in an unperceiving substance, then surely it follows, that no figure or mode of extension which we can either perceive or imagine, or have any idea of, an be really inherent in matter. (Three Dialogues 139) According to Berkeley, only qualities of matter exist, and only in the perceiving mind. For instance, fire as an object does not exist, but the sensation it produces in the mind does because the mind can perceive it. Outside of the perception of heat, fire does not exist because the mind is not present to acknowledge it (123-128). Berkeley expands this principle further to justify the existence of God, arguing that for ideas to be perceivable, they must be perceived. Thus, anything that cannot be perceived by the mind can only exist in the mind of Go... ...rcular Ruins," or a culmination of several different forces, as in "Tlà ¶n, Uqbar, Orbis Tertius" (59). Subjective idealism is enough to explain the nature of human perception, but is hopelessly theocentric concerning Berkeley’s ultimate purpose. Borges exploits this weakness, and subsequently uses Berkeley’s crowning philosophical achievement to defend agnosticism and reinforce the uncertainty surrounding God. Works Cited Berkeley, George. Principles of Human Knowledge. London: Penguin, 1988. Three Dialogues Between Hylas and Philonous. London: Penguin, 1988. Borges, Jorge Luis. Ficciones. Trans. Emecà © Editores. New York: Grove Press, 1962. Dunham, Lowell and Ivar Ivask. The Cardinal Points of Boges. Norman: University of Oklahoma Press, 1971. Muehlmann, Robert G. Berkeley’s Metaphysics. University Park: The Pennsylvania State University Press, 1995.

Identity, Perception, Action and Choice in Contemporary and Traditional :: Philosophy Philosophical Essays

Identity, Perception, Action and Choice in Contemporary and Traditional "No-Self" Theories ABSTRACT: The ego is traditionally held to be synonymous with individual identity and autonomy, while the mind is widely held to be a necessary basis of cognition and volition, with responsibility following accordingly. However Buddhist epistemology, existential phenomenology and poststructuralism all hold the notion of an independent, subsisting, self-identical subject to be an illusion. This not only raises problems for our understanding of cognition (if the self is an illusion, then who does the perceiving and who is deluded) and volition (who initiates acts), as well as for the notion of responsibility (in the absence of an independently subsisting subject there appears to be no autonomous agent). For Buddhism, no-self theory raises serious problems for the doctrine of reincarnation (in the absence of a self, who is responsible for failing to overcome desires and attachments; furthermore, who gets reincarnated?). Arguing for such "no-self" theories, the paper attempts to demonstr ate how such difficulties can nevertheless be resolved. The self is traditionally held to be synonymous with individual identity and autonomy, while the mind, which is closely associated therewith, is widely held to be a necessary basis of cognition and volition, and the responsibility following therefrom. However Buddhism, Existential Phenomenology and Postsructuralism all point out that we have neither direct empirical experience of, nor sufficient justification for inferring, the existence of an independently subsisting self. Buddhists for instance point out that, careful attention to the empirical evidence reveals that all the experiences we have of human subjectivity per se may be characterized in terms of five skandhas or aggregates. These are 1) Form; understood as the Body, including the sense-organs, 2) Feelings and Sensations, 3) Perceptions, 4) Mental Formations (or volitional tendencies) including habits and dispositions etc., and 5) Six Consciousnesses, consisting of the consciousness or awareness of sensations emanating from each of the five senses, plus a consciousness of non-sensory or purely mental experiences. Noting the changing nature of each of these skandhas, they conclude that there is no adequate justification for the common inference that these constantly changing phenomena are changing appearances of a persistent, independently subsisting self or ego. Nor, as Phenomenologists and others have pointed out, do we experience a mind as such, — which much Western Philosophy regards, if not as synonymous with, then certainly essential to, individual identity and autonomy, — independent of the constantly changing sensations, perceptions, feelings, thoughts and ideas etc.

Literary Genre Essay

Literature (from Latin litteraetantri (plural); letter) is the art of written works, and is not bound to published sources (although, under circumstances unpublished sources can be exempt). Literally translated, the word literature means â€Å"acquaintance with letters† (as in the â€Å"arts and letters†). The two major classification of literature are poetry and prose. â€Å"Literature† is sometimes differentiated from popular and ephemeral classes of writing. Terms such as â€Å"literary fiction† and â€Å"literary merit† are used to distinguish individual works as art-literature rather than vernacular writing, and some critics exclude works from being â€Å"literary†, for example, on grounds of weak or faulty style, use of slang, poor characterization and shallow or contrived construction. Others exclude all genres such as romance, crime and mystery, science fiction, horror and fantasy. Pop lyrics, which are not technically a written medium at all, have also been drawn into this controversy. POETRY A poem is a composition written in verse (although verse has been equally used for epic and dramatic fiction). Poems rely heavily on imagery, precise word choice, and metaphor; they may take the form of measures consisting of patterns of stresses (metric feet) or of patterns of different-length syllables (as in classical prosody); and they may or may not utilize rhyme. Relaxation Through Poetry is a tool used to help someone relax in times of stress. One cannot readily characterize poetry precisely. Typically though, poetry as a form of literature makes some significant use of the formal properties of the words it uses – the properties of the written or spoken form of the words, independent of their meaning. Meter depends on syllables and on rhythms of speech; rhyme and alliteration depend on the sounds of words. Arguably, poetry pre-dates other forms of literature. Early examples include the Sumerian Epic of Gilgamesh (dated from around 2700 B. C. ), parts of the Bible, the surviving works of Homer (the Iliad and the Odyssey), and the Indian epics Ramayana and Mahabharata. In cultures based primarily on oral traditions the formal characteristics of poetry often have a mnemonic function, and important texts: legal, genealogical or moral, for example, may appear first in verse form. Some poetry uses specific forms. Examples include the haiku, the limerick, and the sonnet. A traditional haiku written in Japanese relate to nature, contain seventeen onji (syllables), distributed over three lines in groups of five, seven, and five, and should also have a kigo, a specific word indicating a season. A limerick has five lines, with a rhyme scheme of AABBA, and line lengths of 3,3,2,2,3 stressed syllables. It traditionally has a less reverent attitude towards nature. Poetry not adhering to a formal poetic structure is called â€Å"free verse† Language and tradition dictate some poetic norms: Persian poetry always rhymes, Greek poetry rarely rhymes, Italian or French poetry often does, English and German poetry can go either way. Perhaps the most paradigmatic style of English poetry, blank verse, as exemplified in works by Shakespeare and Milton, consists of unrhymed iambic pentameters. Some languages prefer longer lines; some shorter ones. Some of these conventions result from the ease of fitting a specific language’s vocabulary and grammar into certain structures, rather than into others; for example, some languages contain more rhyming words than others, or typically have longer words. Other structural conventions come about as the result of historical accidents, where many speakers of a language associate good poetry with a verse form preferred by a particular skilled or popular poet. Works for theatre (see below) traditionally took verse form. This has now become rare outside opera and musicals, although many would argue that the language of drama remains intrinsically poetic. In recent years, digital poetry has arisen that takes advantage of the artistic, publishing, and synthetic qualities of digital media. An essay consists of a discussion of a topic from an author’s personal point of view, exemplified by works by Michel de Montaigne or by Charles Lamb. ‘Essay’ in English derives from ‘attempt. ‘ Thus, one can find open-ended, provocative and/or inconclusive essays. The term â€Å"essays† first applied to the self-reflective musings of Michel de Montaigne–even today he has a reputation as the father of this literary form. Genres related to the essay may include: †¢the memoir, telling the story of an author’s life from the author’s personal point of view †¢the epistle: usually a formal, didactic, or elegant letter. †¢works by Lady Murasaki[citation needed], the Arabic Hayy ibn Yaqdhan by Ibn Tufail, the Arabic Theologus Autodidactus by Ibn al-Nafis, and the Chinese Romance of the Three Kingdoms by Luo Guanzhong[citation needed]. Early novels in Europe did not count as significant litera perhaps because â€Å"mere† prose writing seemed easy and unimportant. It has become clear, however, that prose writing can provide aesthetic pleasure without adhering to poetic forms. Additionally, the freedom authors gain in not having to concern themselves with verse structure translates often into a more complex plot or into one richer in precise detail than one typically finds even in narrative poetry. This freedom also allows an author to experiment with many different literary and presentation styles—including poetry—in the scope of a single novel. Other prose literature Philosophical, historical, journalistic, legal and scientific writings are traditionally ranked as literature. They offer some of the oldest prose writings in existence; novels and prose stories earned the names â€Å"fiction† to distinguish them from factual writing or nonfiction, which writers historically have crafted in prose. Natural science As advances and specialization have made new scientific research inaccessible to most audiences, the â€Å"literary† nature of science writing has become less pronounced over the last two centuries. Now, science appears mostly in journals. Scientific works of Aristotle, Copernicus, and Newton still possess great value, but since the science in them has largely become outdated, they no longer serve for scientific instruction. Yet, they remain too technical to sit well in most programmes of literary study. Outside of â€Å"history of science† programmes, students rarely read such works. Philosophy Philosophy, too, has become an increasingly academic discipline. More of its practitioners lament this situation than occurs with the sciences; nonetheless most new philosophical work appears in academic journals. Major philosophers through history—Plato, Aristotle, Augustine, Descartes, Kierkegaard, Nietzsche—have become as canonical as any writers. Some recent philosophy works are argued to merit the title â€Å"literature†, such as some of the works by Simon Blackburn; but much of it does not, and some areas, such as logic, have become extremely technical to a degree similar to that of mathematics. History A great deal of historical writing ranks as literature, particularly the genre known as creative nonfiction. So can a great deal of journalism, such as literary journalism. However these areas have become extremely large, and often have a primarily utilitarian purpose: to record data or convey immediate information. As a result the writing in these fields often lacks a literary quality, although it often and in its better moments has that quality. Major â€Å"literary† historians include Herodotus, Thucydides and Procopius, all of whom count as canonical literary figures. Law Law offers a less clear case. Some writings of Plato and Aristotle, or even the early parts of the Bible, might count as legal literature. The law tables of Hammurabi of Babylon might count. Roman civil law as codified in the Corpus Juris Civilis during the reign of Justinian I of the Byzantine Empire has a reputation as significant literature. The founding documents of many countries, including Constitutions and Law Codes, can count as literature; however, most legal writings rarely exhibit much literary merit, as they tend to be rather garrulous. Drama A play or drama offers another classical literary form that has continued to evolve over the years. It generally comprises chiefly dialogue between characters, and usually aims at dramatic / theatrical performance (see theatre) rather than at reading. During the 18th and 19th centuries, opera developed as a combination of poetry, drama, and music. Nearly all drama took verse form until comparatively recently. Shakespeare could be considered drama. Romeo and Juliet, for example, is a classic romantic drama generally accepted as literature. Greek drama exemplifies the earliest form of drama of which we have substantial knowledge. Tragedy, as a dramatic genre, developed as a performance associated with religious and civic festivals, typically enacting or developing upon well-known historical or mythological themes. Tragedies generally presented very serious themes. With the advent of newer technologies, scripts written for non-stage media have been added to this form. War of the Worlds (radio) in 1938 saw the advent of literature written for radio broadcast, and many works of Drama have been adapted for film or television. Conversely, television, film, and radio literature have been adapted to printed or electronic media. Oral literature The term oral literature refers not to written, but to oral traditions, which includes different types of epic, poetry and drama, folktales, ballads. However the use of this oxymoron is controversial and not generally accepted by the scientific community. Some prefer to avoid the etymological question using â€Å"oral narrative tradition†, â€Å"oral sacred tradition†, â€Å"oral poetry† or directly using epics or poetry (terms that no necessarily imply writing), others prefer to create neologisms as orature.

Research on Warehouse Design

European Journal of Operational Research 203 (2010) 539–549 Contents lists available at ScienceDirect European Journal of Operational Research journal homepage: www. elsevier. com/locate/ejor Invited Review Research on warehouse design and performance evaluation: A comprehensive review Jinxiang Gu a, Marc Goetschalckx b,*, Leon F. McGinnis b a b Nestle USA, 800 North Brand Blvd. , Glendale, CA 91203, United States Georgia Institute of Technology, 765 Ferst Dr. , Atlanta, GA 30332-0205, United States a r t i c l e i n f o a b s t r a c tThis paper presents a detailed survey of the research on warehouse design, performance evaluation, practical case studies, and computational support tools. This and an earlier survey on warehouse operation provide a comprehensive review of existing academic research results in the framework of a systematic classi? cation. Each research area within this framework is discussed, including the identi? cation of the limits of previous research and of potential future research directions. O 2009 Elsevier B. V. All rights reserved.Article history: Received 5 December 2005 Accepted 21 July 2009 Available online 6 August 2009 Keywords: Facilities design and planning Warehouse design Warehouse performance evaluation model Case studies Computational tools 1. Introduction This survey and a companion paper (Gu et al. , 2007) present a comprehensive review of the state-of-art of warehouse research. Whereas the latter focuses on warehouse operation problems related to the four major warehouse functions, i. e. , receiving, storage, order picking, and shipping, this paper concentrates on warehouse design, performance evaluation, case studies, and computational support tools.The objectives are to provide an all-inclusive overview of the available methodologies and tools for improving warehouse design practices and to identify potential future research directions. Warehouse design involves ? ve major decisions as illustrated in Fig. 1: deter mining the overall warehouse structure; sizing and dimensioning the warehouse and its departments; determining the detailed layout within each department; selecting warehouse equipment; and selecting operational strategies. The overall structure (or conceptual design) determines the material ? ow pattern within the warehouse, the speci? ation of functional departments, and the ? ow relationships between departments. The sizing and dimensioning decisions determine the size and dimension of the warehouse as well as the space allocation among various warehouse departments. Department layout is the detailed con? guration within a warehouse department, for example, aisle con? guration in the retrieval area, pallet block-stacking pattern in the reserve storage area, and con? guration of an Automated Storage/Retrieval System (AS/RS). The equipment selection deci* Corresponding author. Tel. : +1 404 894 2317; fax: +1 404 894 2301. E-mail address: marc. [email  protected] gatech. edu (M. G oetschalckx). 0377-2217/$ – see front matter O 2009 Elsevier B. V. All rights reserved. doi:10. 1016/j. ejor. 2009. 07. 031 sions determine an appropriate automation level for the warehouse, and identify equipment types for storage, transportation, order picking, and sorting. The selection of the operation strategy determines how the warehouse will be operated, for example, with regards to storage and order picking. Operation strategies refer to those decisions about operations that have global effects on other design decisions, and therefore need to be considered in the design phase.Examples of such operation strategies include the choice between randomized storage or dedicated storage, whether or not to do zone picking, and the choice between sort-while-pick or sortafter-pick. Detailed operational policies, such as how to batch and route the order picking tour, are not considered design problems and therefore are discussed in Gu et al. (2007). It should be emphasized that w arehouse design decisions are strongly coupled and it is dif? cult to de? ne a sharp boundary between them. Therefore, our proposed classi? ation should not be regarded as unique, nor does it imply that any of the decisions should be made independently. Furthermore, one should not ignore operational performance measures in the design phase since operational ef? ciency is strongly affected by the design decisions, but it can be very expensive or impossible to change the design decisions once the warehouse is actually built. Performance evaluation is important for both warehouse design and operation. Assessing the performance of a warehouse in terms of cost, throughput, space utilization, and service provides feedback about how a speci? design or operational policy performs compared with the requirements, and how it can be improved. Furthermore, a good performance evaluation model can help the designer to quickly evaluate many design alternatives and narrow down the design space durin g the early design stage. Performance operational cost for each alternative is estimated using simple analytic equations. Gray et al. (1992) address a similar problem, and propose a multi-stage hierarchical approach that uses simple calculations to evaluate the tradeoffs and prune the design space to a few superior alternatives.Simulation is then used to provide detailed performance evaluation of the resulting alternatives. Yoon and Sharp (1996) propose a structured approach for exploring the design space of order picking systems, which includes stages such as design information collection, design alternative development, and performance evaluation. In summary, published research ndco4h lar02. 8659(war,. 0320Td[(pro2k evaluation methods include benchmarking, analytical models, and simulation models.This review will mainly focus on the former two since simulation results depend greatly on the implementation details and are less amenable to generalization. However, this should not obs cure the fact that simulation is still the most widely used technique for warehouse performance evaluation in the academic literature as well as in practice. Some case studies and computational systems are also discussed in this paper. Research in these two directions is very limited. However, it is our belief that more case studies and computational tools for warehouse design and operation will help to bridge the signi? ant gap between academic research and practical application, and therefore, represent a key need for the future. The study presented in this paper and its companion paper on operations, Gu et al. (2007), complements previous surveys on warehouse research, for example, Cormier (2005), Cormier and Gunn (1992), van den Berg (1999) and Rowenhorst et al. (2000). Over 250 papers are included within our classi? cation scheme. To our knowledge, it is the most comprehensive review of existing research results on warehousing.However, we make no claim that it includes all the literature on warehousing. The scope of this survey has been mainly focused on results published in available English-language research journals. The topic of warehouse location, which is part of the larger area of distribution system design, is not addressed in this current review. A recent survey on warehouse location is provided by Daskin et al. (2005). The next four sections will discuss the literature on warehouse design, performance evaluation, case studies, and computational systems, respectively. The ? al section gives conclusions and future research directions. 2. Warehouse design 2. 1. Overall structure The overall structure (or conceptual design) of a warehouse determines the functional departments, e. g. , how many storage departments, employing what technologies, and how orders will be assembled. At this stage of design, the issues are to meet storage and throughput requirements, and to minimize costs, which may be the discounted value of investment and future operating costs. We can identify only three published papers addressing overall structural design.Park and Webster (1989) assume the functions are given, and select equipment types, storage rules, and order picking policies to minimize total costs. The initial investment cost and annual J. Gu et al. / European Journal of Operational Research 203 (2010) 539–549 541 Levy (1974), Cormier and Gunn (1996) and Goh et al. (2001) consider warehouse sizing problems in the case where the warehouse is responsible for controlling the inventory. Therefore, the costs in their models include not only warehouse construction cost, but also inventory holding and replenishment cost.Levy (1974) presents analytic models to determine the optimal storage size for a single product with either deterministic or stochastic demand. Assuming additional space can be leased to supplement the warehouse, Cormier and Gunn (1996) propose closed-form solution that yields the optimal warehouse size, the optimal amount of space to lease in each period, and the optimal replenishment quantity for a single product case with deterministic demand. The multi-product case is modeled as a nonlinear optimization problem assuming that the timing of replenishments is not managed.Cormier and Gunn (1999) developed a nonlinear programming formulation for the optimal warehouse expansion over consecutive time periods. Goh et al. (2001) ? nd the optimal storage size for both single-product and multi-product cases with deterministic demand. They consider a more realistic piecewise linear model for the warehouse construction cost instead of the traditional linear cost model. Furthermore, they consider the possibility of joint inventory replenishment for the multi-product case, and propose a heuristic to ? nd the warehouse size.The effects of inventory control policies (e. g. , the reorder point and ordering quantity) on the total required storage capacity are shown by Rosenblatt and Roll (1988) using simulation. Our a bility to answer warehouse sizing questions would be signi? cantly enhanced by two types of research. First, assessing capacity requirements should consider seasonality, storage policy, and order characteristics, because these three factors interact to impact the achievable storage ef? ciency, i. e. that fraction of warehouse capacity that can actually be used effectively.Second, sizing models all employ cost models, and validation studies of these models would be a signi? cant contribution. 2. 2. 2. Warehouse dimensioning The warehouse dimensioning problem translates capacity into ? oor space in order to assess construction and operating costs, and was ? rst modeled by Francis (1967), who used a continuous approximation of the storage area without considering aisle structure. Bassan et al. (1980) extends Francis (1967) by considering aisle con? gurations. Rosenblatt and Roll (1984) integrate the optimization model in Bassan et al. 1980) with a simulation model which evaluates the s torage shortage cost, a function of storage capacity and number of zones. They assume single-command tours in order to evaluate the effect of warehouse dimension on the operational cost, and therefore their approach is not applicable to warehouses that perform multi-command operations (e. g. , interleaving put-away and retrieval, or retrieving multiple items per trip). The work discussed so far has approached the sizing and dimensioning problem assuming the warehouse has a single storage department.In reality, a warehouse might have multiple departments, e. g. , a forward-reserve con? guration, or different storage departments for different classes of Stock Keeping Units (SKUs). These different departments must be arranged in a single warehouse and compete with each other for space. Therefore, there are tradeoffs in determining the total warehouse size, allocating the warehouse space among departments, and determining the dimension of the warehouse and its departments. Research stud ying these tradeoffs in the warehouse area is scarce.Pliskin and Dori (1982) propose a method to compare alternative space allocations among different warehouse departments based on multi-attribute value functions, which explicitly capture the tradeoffs among different criteria. Azadivar (1989) proposes an approach to optimally allocate space between two departments: one is ef? cient in terms of storage but inef? cient in terms of operation, while the other is the opposite. The objective is to achieve the best system performance by appropriately allocating space between these two departments to balance the storage capacity and operational ef? iency tradeoffs. Heragu et al. (2005) consider a warehouse with ? ve functional areas, i. e. , receiving, shipping, cross-docking, reserve, and forward. They propose an optimization model and a heuristic algorithm to determine the assignment of SKUs to the different storage areas as well as the size of each functional area to minimize the total material handling and storage costs. A key issue with all research on the dimensioning problem is that it requires performance models of material handling; these models are often independent of the size or layout of the warehouse.Research is needed to either validate these models, or develop design methods that explicitly consider the impact of sizing and dimensioning on material handling. 2. 3. Department layout In this section we discus layout problems within a warehouse department, primarily a storage department. The storage problems are classi? ed as: (P1) pallet block-stacking pattern, i. e. , storage lane depth, number of lanes for each depth, stack height, pallet placement angle with regards to the aisle, storage clearance between pallets, and length and width of aisles; (P2) storage department layout, i. . , door location, aisle orientation, length and width of aisles, and number of aisles; and (P3) AS/RS con? guration, i. e. , dimension of storage racks, number of cranes. These layout problems affect warehouse performances with respect to: (O1) construction and maintenance cost; (O2) material handling cost; (O3) storage capacity, e. g. , the ability to accommodate incoming shipments; (O4) space utilization; and (O5) equipment utilization. Each problem is treated in the literature by different authors considering a subset of the performance measures, as summarized in Table 1. 2. 3. 1.Pallet block-stacking pattern (P1) In the pallet block-stacking problem, a fundamental decision is the selection of lane depths to balance the tradeoffs between space utilization and ease of storage/retrieval operations, considering the SKUs’ stackability limits, arriving lot sizes, and retrieval patterns. Using deep lane storage could increase space utilization because fewer aisles are needed, but on the other hand could also cause decreased space utilization due to the ‘‘honeycombing† effect that creates unusable space for the storage of other i tems until the whole lane is totally depleted.The magnitude of the honeycombing effect depends on lane depths as well as the withdrawal rates of individual products. Therefore, it might be bene? cial to store different classes of products in different lane depths. A careful determination and coordination of the lane depths for different products is necessary in order to achieve the best storage space utilization. Besides lane con? guration, the pallet block-stacking problem also determines such decisions as aisle widths and orientation, stack height, and storage clearance, which all affect storage space utilization, material handling ef? iency, and storage capacity. 542 J. Gu et al. / European Journal of Operational Research 203 (2010) 539–549 Table 1 A summary of the literature on warehouse layout design. Problem P1 Citation Moder and Thornton (1965) Berry (1968) Marsh (1979) Marsh (1983) Goetschalckx and Ratliff (1991) Larson et al. (1997) Roberts and Reed (1972) Bassan et al. (1980) Rosenblatt and Roll (1984) Pandit and Palekar (1993) P3 Karasawa et al. (1980) Ashayeri et al. 1985) Rosenblatt et al. (1993) Objective O4 O2, O4 O3, O4 O4 O2, O4 O1, O2 O1, O2 O1, O2, O3 O2 O1, O2, O3 O1, O2 O1, O2, O3 O1, O5 O1, O5 O1 Method Analytical formulae Analytical formulae Simulation models Heuristic procedure Heuristic procedure Dynamic Programming Optimal design using analytical formulation Optimal two-dimensional search method Queuing model Nonlinear mixed integer problem Nonlinear mixed integer problem Nonlinear mixed integer problem NotesMainly on lane depth determination For class-based storage Consider the con? guration of storage bays (unit storage blocks) Consider horizontal and vertical aisle orientations, locations of doors, and zoning of the storage area Based on Bassan et al’s work with additional costs due to the use of grouped storage Include not only the ordinary travel time, but also waiting time when all vehicles are busy The model is so lved by generalized Lagrange multiplier method Given rack height, the model can be simpli? d to a convex problem System service is evaluated using simulations, if not satisfactory, new constraints are added and the optimization model is solved again to get a new solution A more elaborated variation of Zollinger’s rules that consider explicitly operational policies For the design of an automated carousel system. The model is solved with a simple search algorithm P2 Zollinger (1996) Malmborg (2001) Lee and Hwang (1988) Rule of thumb heuristic Rule of thumb heuristic Nonlinear integer program A number of papers discuss the pallet block-stacking problem.Moder and Thornton (1965) consider ways of stacking pallets in a warehouse and the in? uence on space utilization and ease of storage and retrieval. They consider such design factors as lane depth, pallet placement angle with regards to the aisle, and spacing between storage lanes. Berry (1968) discusses the tradeoffs between stor age ef? ciency and material handling costs by developing analytic models to evaluate the total warehouse volume and the average travel distance for a given storage space requirement.The factors considered include warehouse shape, number, length and orientation of aisles, lane depth, throughput rate, and number of SKUs contained in the warehouse. It should be noted that the models for total warehouse volume and models for average travel distance are not integrated, and the warehouse layout that maximizes storage ef? ciency is different from the one that minimizes travel distance. Marsh (1979) uses simulation to evaluate the effect on space utilization of alternate lane depths and the rules for assigning incoming shipments to lanes.Marsh (1983) compares the layout design developed by using the simulation models of Marsh (1979) and the analytic models proposed by Berry (1968). Goetschalckx and Ratliff (1991) develop an ef? cient dynamic programming algorithm to maximize space utilizati on by selecting lane depths out of a limited number of allowable depths and assigning incoming shipments to the different lane depths. Larson et al. (1997) propose a three-step heuristic for the layout problem of class-based pallet storage with the purpose to maximize storage space utilization and minimize material handling cost. The ? st phase determines the aisles layout and storage zone dimensions; the second phase assigns SKUs to storage con? gurations; and the third phase assigns ? oor space to the storage con? gurations. The research addressing the pallet block-stacking problem suggests different rules or algorithms, usually with restrictive assumptions, e. g. , the replenishment quantities and retrieval frequencies for each SKU are known. In reality, not only do these change dynamically, but the SKU set itself changes, and pallet block-stacking patterns that are optimized for current conditions may be far from optimum in the near future.Research is needed that will identify a robust solution in the face of dynamic uncertainty in the storage and retrieval requirements. 2. 3. 2. Storage department layout (P2) The storage department layout problem is to determine the aisle structure of a storage department in order to minimize the construction cost and material handling cost. The decisions usually include aisle orientations, number of aisles, length and width of aisles, and door locations.In order to evaluate operational costs, some assumptions are usually made about the storage and order picking policies; random storage and single-command order picking are the most common assumptions. By assuming a layout con? guration, or a small set of alternative con? gurations, models can be formulated to optimize each con? guration. Roberts and Reed (1972) assume storage space is available in units of identical bays. Bassan et al. (1980) consider a rectangular warehouse, and aisles that are either parallel or perpendicular to the longest walls.In addition, they also discuss the optimal door locations in the storage department, and the optimal layout when the storage area is divided into different zones. Roll and Rosenblatt (1983) extend Bassan et al. (1980) to include the additional cost due to the use of grouped storage policy. Pandit and Palekar (1993) minimize the expected response time of storage and/or retrieval requests using a queuing model to calculate the total response time including waiting and processing time for different types of layouts. With these response times, an optimization model is solved to ? nd the optimal storage space con? urations. Roodbergen and Vis (2006) present an optimization approach for selecting the number and length of aisles and the depot location so as to minimize the expected length of a picking tour. They developed models for both S-shaped tours and a largest gap policy, and concluded that the choice of routing policy could, in some cases, have a signi? cant impact on the size and layout of the department . The conclusion from Roodbergen and Vis (2006) is quite significant, since it calls into question the attempt to optimize storage department layout without knowing what the true material handling performance will be.There is a need for additional research that helps to identify the magnitude of the impact of layout (for reasonably shaped departments) on total costs over the life of the warehouse, considering changing storage and retrieval requirements. J. Gu et al. / European Journal of Operational Research 203 (2010) 539–549 543 2. 3. 3. AS/RS con? guration (P3) The AS/RS con? guration problem is to determine the numbers of cranes and aisles, and storage rack dimension in order to minimize construction, maintenance, and operational cost, and/or maximize equipment utilization.The optimal design models or rule-ofthumb procedures summarized in Table 1 typically utilize some empirical expressions of the costs based on simple assumptions for the operational policies, and known s torage and retrieval rates. Karasawa et al. (1980) present a nonlinear mixed integer formulation with decision variables being the number of cranes and the height and length of storage racks and costs including construction and equipment costs while satisfying service and storage capacity requirements. Ashayeri et al. 1985) solve a problem similar to Karasawa et al. (1980). Given the storage capacity requirement and the height of racks, their models can be simpli? ed to include only a single design variable, i. e. , the number of aisles. Furthermore, the objective function is shown to be convex in the number of aisles, which allows a simple one-dimensional search algorithm to optimally solve the problem. Rosenblatt et al. (1993) propose an optimization model that is a slight modi? cation of Ashayeri et al. (1985), which allows a crane to serve multiple aisles.A combined optimization and simulation approach is proposed, where the optimization model generates an initial design, and a simulation evaluates performance, e. g. , service level. If the constraints evaluated by simulation are satis? ed, then the procedure stops. Otherwise, the optimization model is altered by adding new constraints that have been constructed by approximating the simulation results. Zollinger (1996) proposes some rule of thumb heuristics for designing an AS/RS. The design criteria include the total equipment costs, S/ R machine utilization, service time, number of jobs waiting in the queue, and storage space requirements.Closed form equations compute these criteria as functions of the number of aisles and the number of levels in the storage rack. Malmborg (2001) uses simulation to re? ne the estimates of some of the parameters which then are used in the closed form equations. The design of automated carousel storage systems is addressed by Lee and Hwang (1988). They use an optimization approach to determine the optimal number of S/R machines and the optimal dimensions of the carousel sy stem to minimize the initial investment cost and operational costs over a ? ite planning horizon subject to constraints for throughput, storage capacity, and site restrictions. Some other less well-discussed AS/RS design problems include determining the size of the basic material handling unit and the con? guration of I/O points. Roll et al. (1989) propose a procedure to determine the single optimal container size in an AS/RS, which is the basic unit for storage and order picking. Container size has a direct effect on space utilization, and therefore on the equipment cost since the storage capacity requirement needs to be satis? ed. Randhawa et al. 1991) and Randhawa and Shroff (1995) use simulations to investigate different I/O con? gurations on performance such as throughput, mean waiting time, and maximum waiting time. The results indicate that increased system throughput can be achieved using I/O con? gurations different from the common one-dock layout where the dock is located at the end of the aisle. There are two important opportunities for additional research on AS/RS con? guration: (1) results for a much broader range of technology options, e. g. , double deep rack, multi-shuttle cranes, etc. ; and (2) results demonstrating the sensitivity of con? urations to changes in the expected storage and retrieval rates or the effects of a changing product mix. 2. 4. Equipment selection The equipment selection problem addresses the level of automation in a warehouse and what type of storage and material han- dling systems should be employed. These decisions obviously are strategic in nature in that they affect almost all the other decisions as well as the overall warehouse investment and performance. Determining the best level of automation is far from obvious in most cases, and in practice it is usually determined based on the personal experience of designers and managers.Academic research in this category is extremely rare. Cox (1986) provides a methodology t o evaluate different levels of automation based on a cost-productivity analysis technique called the hierarchy of productivity ratios. White et al. (1981) develop analytical models to compare block stacking, single-deep and doubledeep pallet rack, deep lane storage, and unit load AS/RS in order to determine the minimum space design. Matson and White (1981) extend White et al. (1981) to develop a total cost model incorporating both space and material handling costs, and demonstrate the effect of handling requirements on the optimum storage design.Sharp et al. (1994) compare several competing small part storage equipment types assuming different product sizes and dimensions. They considered shelving systems, modular drawers, gravity ? ow racks, carousel systems, and mini-load storage/retrieval systems. The costs they considered include operational costs, ? oor space costs, and equipment costs. In summary, research on equipment selection is quite limited and preliminary, although it is very important in the sense that it will affect the whole warehouse design and the overall lifetime costs.There are two fundamental issues for equipment selection: (1) how to identify the equipment alternatives that are reasonable for a given storage/retrieval requirement; and (2) how to select among the reasonable alternatives. A very signi? cant contribution would be to develop a method for characterizing requirements and characterizing equipment in such a way that these two issues could be addressed in a uni? ed manner. 2. 5. Operation strategy This section discusses the selection of operation strategies in a warehouse.The focus is on operation strategies that, once selected, have important effects on the overall system and are not likely to be changed frequently. Examples of such strategies are the decision between randomized and dedicated storage, or the decision to use zone picking. Two major operation strategies are discussed: the storage strategy and the order picking strat egy. Detailed operation policies and their implementations are discussed in Gu et al. (2007). 2. 5. 1. Storage The basic storage strategies include random storage, dedicated storage, class-based storage, and Duration-of-Stay (DOS) based storage, as explained in Gu et al. 2007). Hausman et al. (1976), Graves et al. (1977) and Schwarz et al. (1978) compare random storage, dedicated storage, and class-based storage in single-command and dual-command AS/RS using both analytical models and simulations. They show that signi? cant reductions in travel time are obtainable from dedicated storage compared with random storage, and also that class-based storage with relatively few classes yields travel time reductions that are close to those obtained by dedicated storage.Goetschalckx and Ratliff (1990) and Thonemann and Brandeau (1998) show theoretically that DOS-based storage policies are the most promising in terms of minimizing traveling costs. Historically, DOS-based policies were dif? cult to implement since they require the tracking and management of each stored unit in the warehouse, but modern WMS’s have this capability. Also the performance of DOS-based policies depends greatly on factors such as the skewness of demands, balance of input and output ? ows, inventory control policies, and the speci? cs of implementation. In a study by Kulturel et al. (1999), class-based 544 J. Gu et al. European Journal of Operational Research 203 (2010) 539–549 storage and DOS-based storage are compared using simulations, and the former is found to consistently outperform the latter. This conclusion may have been reached because the assumptions of the DOS model rarely hold true in practice. All the results on operational strategies are for unit-load AS/RS. Studies on other storage systems are rarely reported. Malmborg and Al-Tassan (1998) develop analytic models to evaluate the performance of dedicated storage and randomized storage in lessthan-unit-load warehouses, but no general conclusions comparable to the unit-load case are given.A strong case can be made that additional research is needed, especially to clarify the conditions under which the storage policy does or does not have a signi? cant impact on capacity or travel time. 2. 5. 2. Order picking In a given day or shift, a warehouse may have many orders to pick. These orders may be similar in a number of respects; for example, some orders are shipped using the same carrier, or transportation mode, or have the same pick due date and time.If there are similarities among subsets of orders that require them to be shipped together, then they also should be picked roughly during the same time period to avoid intermediate storage and staging. Thus, it is common practice to use wave picking, i. e. , to release a fraction of the day’s (shift’s) orders, and to expect their picking to be completed within a corresponding fraction of the day (shift). In addition to wave picking, two ot her commonly used orderpicking strategies are batch picking and zone picking.Batch picking involves the assignment of a group of orders to a picker to be picked simultaneously in one trip. In zone picking, the storage space is divided into picking zones and each zone has one or more assigned pickers who only pick in their assigned zone. Zone picking can be divided into sequential and parallel zone picking. Sequential zone picking is similar to a ? ow line, in which containers that can hold one or more orders are passed sequentially through the zones; the pickers in each zone pick the products within their zone, put them into the container, and then pass the container to the next zone. Bartholdi et al. (2000) propose a Bucket Brigades order picking method that is similar to sequential zone picking, but does not require pickers to be restricted to zones). In parallel zone picking, an order is picked in each zone simultaneously. The picked items are sent to a downstream sorting system to be combined into orders. The organization and planning of the order picking process has to answer the following questions: 1. Will product be transported to the picker (part-to-picker) or will the picker travel to the storage location (picker-to-part)? . Will orders be picked in waves? If so, how many waves of what duration? 3. Will the warehouse be divided into zones? If so, will zones be picked sequentially or concurrently? 4. Will orders be picked in batches or separately? If they are batched, will they be sorted while picking or after picking? Depending on the operating principles selected, the order picking methods will be:        Single order picking. Batching with sort-while-pick. Batching with sort-after-pick. Sequential zoning with single order picking. Sequential zoning with batching.Concurrent zoning without batching. Concurrent zoning with batching. Research on the selection of an order picking strategy is very scarce, which might be a result of the complexity of the problem itself. Lin and Lu (1999) compare single-order picking and batch zone picking for different types of orders, which are classi? ed based on the order quantity and the number of ordered items. Petersen (2000) simulates ? ve different order-picking policies: singleorder picking, batch picking, sequential zone picking, concurrent zone picking, and wave picking.Two control variables in the simulation study are the numbers of daily orders and the demand skewness, while the other factors such as warehouse layout, storage assignment, and zone con? guration (when zone and wave picking are used) are ? xed. The performance measures used to compare the different policies include: the mean daily labor, the mean length of day, and the mean percentage of late orders. For each order picking policy, the simplest rules regarding batching, routing, and wave length are used. It also should be noted that the performance measures are mainly related to order picking ef? iencies and service quality; additional costs caused by downstream sorting with batch, zone, and wave picking are not considered. Furthermore, comparison of these policies are made mainly with regards to the order structures, while other important factors such as storage assignment and detailed implementations of the order picking policies are assumed to be ? xed. Therefore, the results should not be considered generic and more research in this direction is required to provide more guidance for warehouse designers. Order picking strategy selection remains a largely unresolved design problem.Additional research would be valuable, especially if it could begin to characterize order picking alternatives in ways that were easy to apply in design decision making. As an example, could researchers develop performance curves for different order picking strategies? 3. Performance evaluation Performance evaluation provides feedback on the quality of a proposed design and/or operational policy, and more importantl y, on how to improve it. There are different approaches for performance evaluation: benchmarking, analytic models, and simulations. This section will only discuss benchmarking and analytic models. 3. 1.Benchmarking Warehouse benchmarking is the process of systematically assessing the performance of a warehouse, identifying inef? ciencies, and proposing improvements. Data Envelopment Analysis (DEA) is regarded as an appropriate tool for this task because of its capability to capture simultaneously all the relevant inputs (resources) and outputs (performances), to construct the best performance frontier, and to reveals the relative shortcomings of inef? cient warehouses. Schefczyk (1993), Hackman et al. (2001), and Ross and Droge (2002) shows some approaches and case studies of using DEA in warehouse benchmarking.An Internet-based DEA system (iDEAS) for warehouses is developed by the Keck Lab at Georgia Tech, which includes information on more than 200 warehouses (McGinnis, 2003). 3. 2. Analytical models Analytic performance models fall into two main categories: (1) aisle based models which focus on a single storage system and address travel or service time; and (2) integrated models which address either multiple storage systems or criteria in addition to travel/service times. J. Gu et al. / European Journal of Operational Research 203 (2010) 539–549 545 3. 2. 1.Aisle based models Table 2 summarizes research on travel time models for aislebased systems. A signi? cant fraction of research focuses on the expected travel time for the crane in an AS/RS, for either single command (SC) or dual command (DC) cycles. For both, there is research addressing three different storage policies: in randomized storage, any SKU can occupy any location; in dedicated storage, each SKU has a set of designated locations; and in class based storage, a group of storage locations is allocated to a class of SKUs, and randomized storage is allowed within the group of storage locati ons.The issue with DC cycles is matching up storages and retrievals to minimize the dead-head travel of the crane, which may involve sequencing retrievals, and selecting storage locations. The results in this category usually assume in? nite acceleration to simplify the travel time models, although some develop more elaborate models by considering acceleration for the various axes of motion (see, e. g. , Hwang and Lee, 1990; Hwang et al. , 2004b; Chang and Wen, 1997; Chang et al. , 1995).There are a few papers that attack the more mathematically challenging issue of deriving the distribution of travel time (see Foley and Frazelle (1991) and Foley et al. (2002)). The research on carousel travel time models generally parallels corresponding AS/RS research. Given some knowledge of travel time, AS/RS service time models can be developed, considering the times required for load/unload and store/retrieve at the storage slot. Queuing models have been developed assuming various distribution s for travel time, see e. g. Lee (1997), Chow (1986), Hur et al. (2004), Bozer and White (1984), Park et al. (2003a) for AS/RS, Chang et al. (1995) for conventional multi-aisle systems, and for end-of-aisle picking systems, see Bozer and White (1991, 1996), Park et al. (2003a), and Park et al. (1999). Stochastic optimization models have been developed for estimating AS/RS throughput, with constraints on storage queue length and retrieval request waiting time (Azadivar, 1986). The throughput of carousel systems is modeled by Park et al. (2003b) and Meller and Klote (2004).The former consider a system with two carousels and one picker, and derive analytic expressions for the system throughput and picker utilization assuming deterministic and exponential pick time distributions. Meller and Klote (2004) develop throughput models for systems with multiple carousels using an approximate two-server queuing model approach. For conventional multi-aisle storage systems (bin shelving, e. g. ), two kinds of travel time results have been developed: (1) models which estimate the expected travel time; and (2) models of the pdf of travel times.These models require an assumption about the structure of the tour, e. g. , traversal (Hall, 1993), return (Hall, 1993 or Caron et al. , 1998), or largest gap (Roodbergen and Vis, 2006). As long as these models are parameterized on attributes of the storage system design, they can be used to support design by searching over the relevant parameters. As with AS/RS and carousels, there has been research to incorporate travel time models into performance models. Chew and Table 2 Literature of travel time models for different warehouse systems. Randomized storage Unit-load AS/RS Single-command Hausman et al. 1976) Bozer and White (1984) Thonemann and Brandeau (1998) Kim and Seidmann (1990) Hwang and Ko (1988) Lee (1997) Hwang and Lee (1990) Chang et al. (1995) Chang and Wen (1997) Koh et al. (2002) Lee et al. (1999) Graves et al. (1977) Boze r and White (1984) Kim and Seidmann (1990) Hwang and Ko (1988) Lee (1997) Han et al. (1987) Hwang and Lee (1990) Chang et al. (1995) Chang and Wen (1997) Koh et al. (2002) Lee et al. (1999) Meller and Mungwattana (1997) Potrc et al. (2004) Hwang and Song (1993) Bozer and White (1990) Bozer and White (1996) Foley and Frazelle (1991) Park et al. 1999) Han and McGinnis (1986) Han et al. (1988) Su (1998) Hwang and Ha (1991) Hwang et al. (1999) Hall (1993) Jarvis and McDowell (1991) Chew and Tang (1999) Hwang et al. (2004a) Caron et al. (1998) Caron et al. (2000) Jarvis and McDowell (1991) Chew and Tang (1999) Hwang et al. (2004a) Park et al. (2003a) Dedicated storage Hausman et al. (1976) Thonemann and Brandeau (1998) Kim and Seidmann (1990) Class-based storage Hausman et al. (1976) Thonemann and Brandeau (1998) Rosenblatt and Eynan (1989) Eynan and Rosenblatt (1994) Kouvelis and Papanicolaou (1995) Kim and Seidmann (1990) Pan and Wang (1996) Ashayeri et al. 2002) Dual-command Graves et al. (1977) Kim and Seidmann (1990) Graves et al. (1977) Kouvelis and Papanicolaou (1995) Kim and Seidmann (1990) Pan and Wang (1996) Ashayeri et al. (2002) Multi-shuttle Man-on-board AS/RS End-of-aisle AS/RS Carousel and rotary racks Ha and Hwang (1994) Conventional multi-aisle system Jarvis and McDowell (1991) Chew and Tang (1999) Hwang et al. (2004a) 546 J. Gu et al. / European Journal of Operational Research 203 (2010) 539–549 Tang (1999) use their model of the travel time pdf to analyze order batching and storage allocation using a queuing model.Bhaskaran and Malmborg (1989) present a stochastic performance evaluation model for the service process in multi-aisle warehouses with an approximated distribution for the service time that depends on the batch size and the travel distance. de Koster (1994) develops queuing models to evaluate the performance of a warehouse that uses sequential zone picking where each bin is assigned to one or more orders and is transported using a conveyer. If a bin needs to be picked in a speci? c zone, it is transported to the corresponding pick station.After it is picked, it is then put on the conveyor to be sent to the next pick station. The proposed queuing network model evaluates performance measures such as system throughput, picker utilization, and the average number of bins in the system based on factors such as the speed and length of the conveyor, the number of picking stations, and the number of picks per station. Throughput analysis of sorting systems is addressed in Johnson and Meller (2002). They assume that the induction process is the bottleneck of the sorting process, and therefore governs the throughput of the sorting system.This model is later incorporated into a more comprehensive model in Russell and Meller (2003) that integrates order picking and sorting to balance the tradeoffs between picking and packing with different order batch sizes and wave lengths. Russell and Meller (2003) also demonstrate th e use of the proposed model in determining whether or not to automate the sorting process and in designing the sorting system. 3. 2. 2. Integrated models Integrated models combine travel time analysis and the service quality criteria with other performance measures, e. g. storage capacity, construction cost, and operational cost. Malmborg (1996) proposes an integrated performance evaluation model for a warehouse having a forward-reserve con? guration. The proposed model uses information about inventory management, forward-reserve space allocation, and storage layout to evaluate costs associated with: storage capacity and space shortage; inventory carrying, replenishing, and expediting; and order picking and internal replenishment for the forward area. Malmborg (2000) evaluates several performance measures for a twin-shuttle AS/RS.Malmborg and Al-Tassan (2000) present a mathematical model to estimated space requirements and order picking cycle times for less than unit load order pick ing systems that uses randomized storage. The inputs of the model include product parameters, equipment speci? cations, operational policies, and storage area con? gurations. Malmborg (2003) models the dependency of performance measures such as expected total system construction cost and throughput on factors such as the vehicle ? eet size, the number of lifts, and the storage rack con? gurations for warehouse systems that use rail guided vehicles.Table 3 A Summary of the literature on warehouse case studies. Citation Cormier and Kersey (1995) Yoon and Sharp (1995) Zeng et al. (2002) Kallina and Lynn (1976) Brynzer and Johansson (1995) Burkard et al. (1995) van Oudheusden et al. (1988) Dekker et al. (2004) Luxhoj and Skarpness (1986) Johnson and Lofgren (1994) Problems studied Conceptual design Analytic travel time and performance models of storage systems represent a major contribution to warehouse design related research, and a rich set of models is available. Yet despite this wea lth of prior results, there is no uni? d approach to travel time modeling or performance modeling for aisle based systems – every system and every set of assumptions leads to a different model. A signi? cant research contribution would be to present a uni? ed theory of travel time in aisle-based systems. 4. Case studies There are some published industrial case studies, which not only provide applications of the various design and operation methods in practical contexts, but more importantly, also identify possible future research challenges from the industrial point of view. Table 3 lists these case studies, identifying the problems and the types of warehouse they investigated.It is dif? cult to generalize from such a small set of speci? c cases, but one conclusion is that substantial bene? ts can achieved by appropriately designing and operating a warehouse, see for example Zeng et al. (2002), van Oudheusden et al. (1988), and Dekker et al. (2004). On the other hand, one mig ht conclude from these cases that there are few generic simple rules. As just one example, the COI-based storage location assignment rule proposed by Kallina and Lynn (1976) ignores many practical considerations, such as varying weights, item-dependent travel costs, or dependencies between items.Some of these complications have been addressed in the academic research (for example see Table 3 in Section 5. 2 of Gu et al. (2007)), but many others remain unexplored. What these cases illustrate is the gap between the assumption-restricted models in research publications and the complex reality of most warehouses. There is a signi? cant need for more industrial case studies, which will assist the warehouse research community in better understanding the real issues in warehouse design. In turn, research results that have been tested on more realistic data sets will have a more substantial impact on practice.A warehouse design problem classi? cation, such as we have proposed here, might be used to structure such future case studies. 5. Computational systems There are numerous commercial Warehouse Management Systems (WMS) available in the market, which basically help the warehouse manager to keep track of the products, orders, space, equipment, and human resources in a warehouse, and provide rules/algorithms for storage location assignment, order batching, pick routing, etc. Detailed review of these systems is beyond the scope of this paper.Instead, we focus on the academic research addressing computational systems for warehouse design. As previous sections show, research on various warehouse design and Type of warehouse A warehouse for perishable goods that requires Just-In-Time operations An order picking system A distribution center A distribution center Kitting systems that supply materials to assembly lines An AS/RS where a S/R machine can serve any aisle using a switching gangway A man-on-board AS/RS in an integrated steel mill A multi-aisle manual order picking system A distribution center A distribution centerConceptual design Storage location assignment; warehouse dimensioning; storage and order picking policies Storage location assignment using the COI rule Process ? ow; batching; zone picking; Vehicle routing Storage location assignment; batching; routing Storage and routing policies Manpower planning Simulation by decomposition J. Gu et al. / European Journal of Operational Research 203 (2010) 539–549 547 operation problems has been conducted for almost half a century, and as a result, a large number of methodologies, algorithms, and empirical studies have been generated.However, successful implementations of these academic results in current commercial WMS systems or in engineering design software are rare. The prototype systems discussed in this section might shed some light on how academic research results could be utilized to develop more sophisticated computer aided warehouse design and operation systems. Perlmann and Bai ley (1988) present computer-aided design software that allows a warehouse designer to quickly generate a set of conceptual design alternatives including building shape, equipment selection, and operational policy selection, and to select from among them the best one based on the speci? d design requirements. To our knowledge, this is the only research paper addressing computer aided warehouse design. There are several papers on the design of warehouse control systems. Linn and Wysk (1990) develop an expert system for AS/ RS control. A control policy determines decisions such as storage location assignment, which item to retrieve if multi-items for the same product are stored, storage and retrieval sequencing, and storage relocation.Several control rules are available for each decision and the control policy is constructed by selecting one individual rule for each decision in a coherent way based on dynamically changing system state variables such as demand levels and traf? c intensi ty. A similar AS/RS control system is proposed by Wang and Yih (1997) based on neural networks. Ito et al. (2002) propose an intelligent agent based system to model a warehouse, which is composed of three subsystems, i. e. , agent-based communication system, agent-based material handling system, and agent-based inventory planning and control system.The proposed agent-based system is used for the design and implementation of warehouse simulation models. Kim et al. (2002) present an agent based system for the control of a warehouse for cosmetic products. In addition to providing the communication function, the agents also make decisions regarding the operation of the warehouse entities they represented in a dynamic real-time fashion. The absence of research prototypes for computer aided warehouse design is particularly puzzling, given the rapid advancement in computing hardware and software over the past decade.Academic researchers have been at the forefront of computer aided design i n other disciplines, and particularly in developing computational models to support design decision making. Warehousing design, as a research domain, would appear to be ripe for this kind of contribution. 6. Conclusions and discussion We have attempted a thorough examination of the published research related to warehouse design, and classi? ed papers based on the main issues addressed. Fig. 1 shows the numbers of papers in each category; there were 50 papers directly addressing warehouse design decisions.There were an additional 50 papers on various analytic models of travel time or performance for speci? c storage systems or aggregates of storage systems. Benchmarking, case studies and other surveys account for 18 more papers. One clear conclusion is that warehouse design related research has focused on analysis, primarily of storage systems rather than synthesis. While this is somewhat surprising, an even more surprising observation is that only 10% of papers directly addressing w arehouse design decisions have a publication date of 2000 or later.Given the rapid development of computing hardware and solvers for optimization, simulation, and general mathematical problems, one might reasonably expect a more robust design-centric research literature. We conjecture two primary inhibiting factors: 1. The warehouse design decisions identi? ed in Fig. 1 are tightly coupled, and one cannot be analyzed or determined in isolation from the others. Yet, the models available are not uni? ed in any way and are not ‘‘interoperable†. A researcher addressing one decision would require a research infrastructure integrating all the other decisions.The scope and scale of this infrastructure appears too great a challenge for individual researchers. 2. To properly evaluate the impact of changing one of the design decisions requires estimating changes in the operation of the warehouse. Not only are future operating scenarios not speci? ed in detail, even if they w ere, the total warehouse performance assessment models, such as high ? delity simulations, are themselves a considerable development challenge. From this, we conclude that the most important future direction for the warehouse design research community is to ? d ways to overcome these two hurdles. Key to that, we believe, will be the emergence of standard representations of warehouse elements, and perhaps some research community based tools, such as open-source analysis and design models. Other avenues for important contributions include studies describing validated or applied design models, and practical case studies that demonstrate the potential bene? ts of applying academic research results to real problems, or in identifying the hidden challenges that prevent their successful implementation.Finally, both analytic and simulation models are proposed to solve warehouse problems and each has its respective advantages and disadvantages. Analytic models are usually design-oriented in the sense that they can explore many alternatives quickly to ? nd solutions, although they may not capture all the relevant details of the system. On the other hand, simulation models are usually analysis-oriented – they provide an assessment of a given design, but usually have limited capability for exploring the design space. There is an important need to integrate both approaches to achieve more ? exibility in analyzing warehouse problems.This is also pointed out by Ashayeri and Gelders (1985), and its applicability has been demonstrated by Rosenblatt and Roll (1984) and Rosenblatt et al. (1993). There is an enormous gap between the published warehouse research and the practice of warehouse design and operations. Cross fertilization between the groups of practitioners and researchers appears to be very limited. Effectively bridging this gap would improve the state-of-the-art in warehouse design methodology. Until such communication is established, the prospect of meaningfu l expansion and enhancement of warehouse design methodology appears limited.Warehousing is an essential component in any supply chain. 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