My Sports Movie :: Sociology Essays

My Sports MovieI believe that one of the most important things to keep in mind near sports/athletics is that no ones experience is the same. There are many different perspectives that complicate the subject and there is no real clear-cut answer or solution to any problem. But it is always important to bring the issues to the surface where they can be discussed and debated in the hopes of reaching better grounds with a compromise.So, in writing a movie script, I would try and include several different perspectives from people with varying personalities. I would also have to take and lose ones temper on my own experiences. Though my exposure to athletics and the questions surrounding society and women have been limited, I think that what I have been made aware of is corresponding and relevant to the issues today.My movie would follow a small group of high instruct students and their varying experiences with the athletics in their small school.Cathy is a junior and was the prime(pr enominal) girl to try out for and join the wrestling team. She is a very involved with sports and school activities in general. Shes on track and field and does several donnish extra curricular activities as well. But after joining her high school wrestling team, and cutting her hair short, she is picked on and called a dyke. In actuality, she is in a long-term relationship with a male track and field teammate. Mae is a senior and a self-described feminist. She plays on the girls varsity softball team. She too gets called a dyke, but she doesnt get it as bad as Cathy. Mae is also very involved with her academic school activities.Larry is a sophomore and the heir to the Macky Mini-Mart chains. He get together the schools track team to appease his mother. Track and cross-country come easy to him. His older sisters were track stars and his mother is the coach. Halfway through the season however, he lay off and joins the newspaper. All the guys pick on Larry and call him a queer beca use he is soft spoken and seemingly uninterested in everything including team sports.Adette is the editor of the school newspaper. Adette is not involved in any sports and in fact, failed most of her gym classes, but her best friends just happen to be Cathy and Mae. The trouble starts in the midst of senior year Adette is demoted to sports writer after running a scandalous issue.

Military Service Should be Mandatory Essay -- Papers

Military Service Should be Mandatory Americans, especially baby boomers, should be ashamed of themselves. How can the worlds richest population let its military go begging for recruits? Each year, the military gos -- Air Force, Army, Marines, Navy -- establish recruiting goals to maintain adequate numbers of personnel. The numbers change annually depending on, among different factors, service needs, recruitment figures the year before and retention of current troops. Most informed folks are familiar with the sorry statistics, but let me repeat them for the prove The Air Force has a goal of 33,800 for this year it expects to fall short by 1,700. The Army needs 74,500 but will miss the mark by 6,300. Currently short of its goal of 53,200, the Navy expects to have enough recruits by weeks end. Because of its unique tradition, the Marine Corps is the only branch that consistently fills its quota. In all, fit in to the Associated Press, the services need 197,115 recruits to maintain a force of 1.4-million. Why are the services having such a hard time recruiting? One obvious reason, harmonize to the New York Times, is that the number of people between ages 18 and 22, the prime age for recruits, has dropped to approximately 21-million, 5-million fewer than in 1980. Another major reason, of course, is that the economy has opened line of merchandise opportunities to those who otherwise might see the military as an option. These two are real reasons for the shrinking recruiting pool, but I see another reason, one that is perchance at the heart of the problem As a group, those between 18 and 22 are not patriotic. And perhaps even worse, too many baby-boomer parents and other influencers -- teachers and coaches -- bad-mouth the milita... ...y if we expect to recruit effectively. Where I am from, we call such thinking bass ackward. No, we need to scrap the all-volunteer army concept and draft everyone -- including the children of the rich and the hefty in gated encl aves -- who does not volunteer. I leave the logistics to the experts. Unfortunately, money drives everything these days. When parents advise their children on career choices, fewer of them ever mention the military. It is not an option. The New York Times quotes a 17-year-old senior in the class of 2000 about the attitudes of his peers toward the military. His response? Its not even in their vocabularies. As a nation, we should be ashamed. President Clinton is not to blame for this one, folks. every(prenominal) of us -- especially parents, teachers and coaches -- are blameworthy. Everyone who enjoys the freedom of living in America should serve.

Interview Essay - Larry Clayville -- Interview Essays

Interview turn up - Larry ClayvilleLarry Clayville was born in Ustick, Idaho, on June 11, 1917. Larry explained that on that point was once a post office in Ustick, but there is nothing there now. That is how far pop in the woods I was. Larry is a very down to earth man who has seen a the great unwashed of life. He has read the newspaper every twenty-four hours of his life. He is a Father, a Grandfather, and seems to be a friend to m each. Larry came to California for work in 1946. He is a POW survivor, and is a member of the Lodge, and has some(prenominal) friends there. He is also currently involved in a relationship.Larrys rendering of happiness is, Having plenty to eat, having a unattackable place to sleep, and having friends and family. Thats enough to make me joyful.Larry explained that when he was young, happiness was sufferting enough to eat. He said, That was the worst part of the depression, when you thought about it, there were a lot of hungry people. Other than that, his definition of happiness has not changed a lot over the years.How does Larry know when he is smart? When you upright have that cracking old happy feeling. He defines that as, When everything just goes good. You get up in the morning and every thing goes right. You are not mad at any body. Its a good feeling.When Larry is unhappy, he talks to whoever is close. However, he admits that he keeps most of it to himself.Simple things contribute to Larrys happiness. Just the bare necessities of life keep me happy. The activity that keeps Larry happy is Living. He explains, I am happy that I am alive when I wake up in the morning. Oh hey, if I am alive unitary more day, I have a chance.About the only thing that makes Larry unhappy any more is illness. Theres nothing that leave alone ta... ...u dont equivalent, but hey, if you dislike things enough, you will do something about them. When asked if he is delightful with his current interpersonal relationships, Larry said, Yes. Larry also had some thoughts on religion. I know that there is a higher power, and I believe in that. I came from a religious family, and I rebelled against that. But, I do believe there is something there, a Supreme Being or something like that.Larry also gave a piece of advice for achieving happiness. If you deal people nice, they will treat you nice. Generally speaking. That is the way I have lived, somewhat of a golden rule.I think that Larry is an intelligent and understanding person, and I can tell that he is well loved by his family and friends. What I admire most is that he is a survivor, and will not let himself get down over the fact that life is not always fair. Interview Essay - Larry Clayville -- Interview EssaysInterview Essay - Larry ClayvilleLarry Clayville was born in Ustick, Idaho, on June 11, 1917. Larry explained that there was once a post office in Ustick, but there is nothing there now. That is how far out in the woods I was. Larry is a very do wn to earth man who has seen a lot of life. He has read the newspaper every day of his life. He is a Father, a Grandfather, and seems to be a friend to many. Larry came to California for work in 1946. He is a POW survivor, and is a member of the Lodge, and has many friends there. He is also currently involved in a relationship.Larrys definition of happiness is, Having plenty to eat, having a warm place to sleep, and having friends and family. Thats enough to make me happy.Larry explained that when he was young, happiness was getting enough to eat. He said, That was the worst part of the depression, when you thought about it, there were a lot of hungry people. Other than that, his definition of happiness has not changed a lot over the years.How does Larry know when he is happy? When you just have that good old happy feeling. He defines that as, When everything just goes good. You get up in the morning and every thing goes right. You are not mad at any body. Its a good feeling.When La rry is unhappy, he talks to whoever is close. However, he admits that he keeps most of it to himself.Simple things contribute to Larrys happiness. Just the bare necessities of life keep me happy. The activity that keeps Larry happy is Living. He explains, I am happy that I am alive when I wake up in the morning. Oh hey, if I am alive one more day, I have a chance.About the only thing that makes Larry unhappy any more is illness. Theres nothing that will ta... ...u dont like, but hey, if you dislike things enough, you will do something about them. When asked if he is pleased with his current interpersonal relationships, Larry said, Yes.Larry also had some thoughts on religion. I know that there is a higher power, and I believe in that. I came from a religious family, and I rebelled against that. But, I do believe there is something there, a Supreme Being or something like that.Larry also gave a piece of advice for achieving happiness. If you treat people nice, they will treat you ni ce. Generally speaking. That is the way I have lived, somewhat of a golden rule.I think that Larry is an intelligent and understanding person, and I can tell that he is well loved by his family and friends. What I admire most is that he is a survivor, and will not let himself get down over the fact that life is not always fair.

The Donora Death Fog :: Air Pollution Environmental Issues Essays

The Donora Death FogD-Town Back home in Canonsburg, a small suburb outside of Pittsburgh, this is how we refer to Donora. We joke that the only thing in Donora is the tumbler skating rink, but even this is inaccessible to anyone whos not a D-town native because when you are at the age to want to go roller skating you arent brave enough to enter into the Donora city limits. Only dedicated roller-skaters are brave enough to dare the elements of Donora. Of course, one, particularly a girl, would never think of going to Donora alone. But for me, I was never really that scared of Donora because my grandparents live nearby and we used to have dinner at the Ponderosa that has since closed. But, I never missed the opportunity to poke fun at that rough territory. Recently, I drove through D-town. The shops are boarded up. Theres graffiti everywhere. In addition to the roller rink there are a few bars and decrepit restaurants. I always assumed that it was the gigantic Wal-mart that had caused this once thriving town to fall to shambles. But, this town, as I recently learned, was the site of the worst recorded industrial transmission line pollution accident in US storey (The Donora Fluoride Fog). This mishap intrigued me, so I decided to do some research regarding what happened. My investigation first led me to find that twenty people died from October 26-31, 1948 ( public address system DEP). According to the Pennsylvania Department of Transportation website, the town population was about 14,000 at the time of the disaster. Devastatingly, about half-7,000-of those people became ill or hospitalized. My investigation led me to discover that this disaster was created by unchecked industrial emissions and stagnant air conditions (Donoras Killer Smog Noted at 50). These conditions led to a smog fog wall hanging around the area. The American Steel & Wire Co., a subsidiary of the US Steel Group, was the local plant responsible for producing these emissions and conditions. It is also widely accepted that the atmospheric condition conditions were prominent in producing the disaster. In October of 1998, spokespeople for the industry agreed that the disaster was unfortunate and tragic, but did not fail to note that, at the time of the disaster, clean air acts did not exist. If any good could come from this disaster it was the funding for research about clean air and the eventual passing of clean air acts and legislation.

Feminist Criticism of Shakespeares Hamlet Essay -- Shakespeare And Fe

Many literary critics have presented theories on the meaning of William Shakespeares settlement, ranging from claims of Oedipal Complexes to insinuations of homosexuality. Though most such interpretations can be considered true at nigh level, there seems to be some basic theme - some driving force - that underlies all other interpretations. While most criticisms focus on individual characters, a more insightful criticism of the true character of Hamlet can be drawn simply by analyzing the key relationships in play. These relationships - especially those dealing with women or issues of femininity - allow a level of interpretation that examines not merely the events of the play, but the true underlying significance of gender both to Shakespeare and to the characters he presents. In order to interpret the significance of the feminine within the relationships in the play, one must first understand precisely the nature of feminine. Though this term is typically associated only with wom en, Hamlet in many regards breaks down these barriers. While women are almost always feminine in some respect, the male characters in Hamlet are often embodiments of feminine virtues, such as female sexuality, motherhood, or sisterly love. As one author states, thank to feminist criticism, gender is not indissolvably fixed in Shakespeare. Male characters can profitably incorporate female characteristics, and women characters can assume masculine ones (Kolin 5). While the women of Hamlet are the bearers of individual and unique feminine qualities, a feminist interpretation of the work also reveals the broader ideals of femininity within many of the male characters. The first of the actually significant women in Hamlet is Gertrude, Hamlets mother. ... ...nd Feminist Criticism An Annotated Bibliography and Commentary. New York Garland Publishing, Inc., 1991. Erickson, Peter. Patriarchal Structures in Shakespeares Drama. Paraphrased in Philip Kolin, Shakespeare and Feminist Criticism An Annotated Bibliography and Commentary. New York Garland Publishing, Inc., 1991. Klein, Joan Larsen. Angels and Ministers of Grace Hamlet, IV, v-vii. Paraphrased in Philip Kolin, Shakespeare and Feminist Criticism An Annotated Bibliography and Commentary. New York Garland Publishing, Inc., 1991. Kolin, Philip C. Shakespeare And Feminist Criticism An annotated Bibliography and Commentary. New York Garland Publishing. 1991. Web. 26 May 2015.http//www.tandfonline.com/doi/abs/10.1080/0895769X.1995.10545153Watts, Cedric. Twaynes New Critical Introductions to Shakespeare. Boston Twayne Publishers. 1991.

Feminist Criticism of Shakespeares Hamlet Essay -- Shakespeare And Fe

Many literary critics have presented theories on the meaning of William Shakespeares Hamlet, ranging from claims of Oedipal Complexes to insinuations of homosexuality. though most such interpretations squeeze out be considered true at some level, there seems to be some basic theme - some driving office - that underlies all other interpretations. piece of music most criticisms focus on individual characters, a more insightful criticism of the true nature of Hamlet can be drawn simply by analyzing the key relationships in play. These relationships - especially those dealing with women or issues of femininity - allow a level of interpretation that examines non merely the events of the play, but the true underlying significance of gender both to Shakespeare and to the characters he presents. In order to interpret the significance of the feminine within the relationships in the play, one must first understand precisely the nature of feminine. Though this term is typically associated o nly with women, Hamlet in many regards breaks down these barriers. While women are almost always feminine in some respect, the male characters in Hamlet are often embodiments of feminine virtues, such as egg-producing(prenominal) sexuality, motherhood, or sisterly love. As one author states, thanks to feminist criticism, gender is not indissolvably fixed in Shakespeare. Male characters can profitably mix female characteristics, and women characters can assume masculine ones (Kolin 5). While the women of Hamlet are the bearers of individual and unique feminine qualities, a feminist interpretation of the work overly reveals the broader ideals of femininity within many of the male characters. The first of the truly significant women in Hamlet is Gertrude, Hamlets mother. ... ...nd Feminist Criticism An Annotated Bibliography and Commentary. New York Garland Publishing, Inc., 1991. Erickson, Peter. Patriarchal Structures in Shakespeares Drama. Paraphrased in Philip Kolin, Shakespear e and Feminist Criticism An Annotated Bibliography and Commentary. New York Garland Publishing, Inc., 1991. Klein, Joan Larsen. Angels and Ministers of Grace Hamlet, IV, v-vii. Paraphrased in Philip Kolin, Shakespeare and Feminist Criticism An Annotated Bibliography and Commentary. New York Garland Publishing, Inc., 1991. Kolin, Philip C. Shakespeare And Feminist Criticism An annotated Bibliography and Commentary. New York Garland Publishing. 1991. Web. 26 May 2015.http//www.tandfonline.com/doi/abs/10.1080/0895769X.1995.10545153Watts, Cedric. Twaynes New Critical Introductions to Shakespeare. Boston Twayne Publishers. 1991.

P’s Pert Plus: a Pan- European Brand?

Q1. How attractive is the Pan- European market for impudent plus in terms of film potential? Competition? Pan- European market is quite attractive for pert plus in terms of demand as the consumers test results showed that the product design of wash & go their (time- prudence benefits) 28% consumers said that they would definalty buy the product that was only 1 percent less then already established bran there Vidal Sasson. Also because they ar gradually accepting the idea of 2-in-1 shampoo more and thus it would be beneficial to launch in European market.P&Gs competitors there are Unilever, Colgate and Lo Oreal. P&Gs own competitor brands are heavily advertised there by European standards. Therefore launch of the product need to illustrate quality and time- saving benefits and also need to educate the market in the use of conditioners further. Q2. What competitive advantages does Pert Plus have? Disadvantages? Competitive advantage for pert plus is the benefits of time-saving and satisfied everyday use of the product. Thos benefit is very essential and thus required right positioning.Inadequate availability of production capacity was a disadvantage for pert plus. Also lead times for alternative pack sizes and designs (250ml preferred size) were also a restriction for them as it would take six months lead time. Q3. Which countries would be the atomic number 82 markets in Europe? What are the advantages and disadvantages of entering a leading market branch? The countries that could be leading markets are Great Britain as it has a broad(prenominal) market size for usage of conditioners and shampoos, especially conditioners that is the highest rate among the other 4 countries given.Therefore they would non have to educate them much about the usage of conditioners alone can face tough competition. West Germany has highest rate of value of shampoos and 2nd highest in conditioners (Exhibit 1). Therefore has the potential of being a leading market notwithsta nding would require an innovative marketing campaign and emphasis on pert pluss competitive advantages. Entering a leading market first has both advantages and disadvantages. foodstuff segmentation is usually a must as competition is intense.New entrant will have to use niche strategies, positioning their product not in the core of the market but in specialty area. As the product is new it has the chance to develop a new market and grow favorable first mover advantages, something that takes resources, focus and continuous monitoring of penetration. Q4. What does marketing research tell about the price and positioning decision for Europe? soil choice? Should the BC-18 applied science be introduced with a pan-European name, or with topical anaesthetic brand names, or even with a mixture of both approaches?Price and packaging alternatives were tried and true on only two brands one brand from the lower-price segment and another brand that had a high quality product concept that is product concepts where accomplishable price sensitivity would be easily detected. According to the market research the consumer were willing to pay the equal price for the selected product (Vidal Sassoon, Shamtu, Pantene, Pert Plus). The new technology 2-in-1 for shampoo and conditioner in one wash, its positioning was same as Vidal Sassoon Shampoo for great-looking hair in a convenient way.The brand choice would be highly not so easy because all the brands are providing the same technology 2-in-1 formula. The BC-18 technology would be introduced with a mixture of both approaches, because P was the first packaged goods companies to go to pan-European. The American company had established a pan-European focus in its R-effort and a system of lead countries for pan-European product roll-outs. And plus with a local brand name customer would easily recognized the brand globally.

Digital Fortress Chapter 17

David Becker stepped out onto the scorching tile concourse of Plaza de Espana. Before him, El Ayunta miento-the ancient city council building-rose from the trees on a three-acre bed of blue and sporty azulejo tiles. Its Arabic spires and carved facade gave the impression it had been intended more as a palace than a exoteric office. Despite its history of military coups, fires, and public hangings, most tourists visited because the local brochures plugged it as the English military headquarters in the film Lawrence of Arabia. It had been far cheaper for Columbia Pictures to film in Spain than in Egypt, and the Moorish influence on Sevilles architecture was enough to convince moviegoers they were looking at Cairo.Becker reset his Seiko for local time 910 p.m.-still afternoon by local standards a proper Spaniard never ate dinner before sunset, and the lazy Andalusian sun seldom surrendered the skies before ten.Even in the early-evening heat, Becker found himself walking across the p ark at a brisk clip. Strathmores tone had sounded a lot more urgent this time than it had that morning. His new orders left no populate for misinterpretation Find the Canadian, get the ring. Do whatever is necessary, only get that ring.Becker wondered what could possibly be so important about a ring with letter all over it. Strathmore hadnt offered, and Becker hadnt asked. NSA, he thought. Never Say Anything.On the other side of Avenida Isabela Catolica, the clinic was clearly visible-the universal symbol of a red cross in a white circle painted on the roof. The Guardia officer had dropped the Canadian off hours ago. Broken wrist, bumped head-no doubt the patient had been treated and discharged by now. Becker just hoped the clinic had discharge information-a local hotel or phone number where the man could be reached. With a little luck, Becker figured he could find the Canadian, get the ring, and be on his way home without any more complications.Strathmore had told Becker, Use the ten thousand cash to buy the ring if you have to. Ill reimburse you.Thats not necessary, Becker had replied. Hed intended to revert the money anyway. He hadnt gone(a) to Spain for money, hed gone for Susan. Commander Trevor Strathmore was Susans mentor and guardian. Susan owed him a lot a one-day errand was the least Becker could do. Unfortunately, things this morning hadnt gone quite as Becker had planned. Hed hoped to label Susan from the plane and explain everything. He considered having the pilot radio Strathmore so he could pass along a message but was hesitant to involve the delegate director in his romantic problems.Three times Becker had tried to call Susan himself-first from a defunct cellular on board the jet, next from a impart phone at the airport, then again from the morgue. Susan was not in. David wondered where she could be. Hed gotten her answering machine but had not left a message what he wanted to put was not a message for an answering machine.As he approac hed the road, he spotted a phone booth near the park entrance. He jogged over, snatched up the receiver, and used his phone card to place the call. There was a long pause as the number connected. Finally it began to ring.Come on. Be there.After louvre rings the call connected.Hi. This is Susan Fletcher. Sorry Im not in right now, but if you leave your nameBecker listened to the message. Where is she? By now Susan would be panicked. He wondered if maybe shed gone to Stone Manor without him. There was a beep.Hi. Its David. He paused, unsure what to say. One of the things he hated about answering machines was that if you stopped to think, they cut you off. Sorry I didnt call, he blurted just in time. He wondered if he should tell her what was going on. He thought better of it. Call Commander Strathmore. Hell explain everything. Beckers heart was pounding. This is absurd, he thought. I love you, he added quickly and hung up.Becker waited for some traffic to pass on Avenida Borbolla. He thought about how Susan undoubtedly would have assumed the shell it was unlike him not to call when hed promised to.Becker stepped out onto the four-lane boulevard. In and out, he whispered to himself. In and out. He was too preoccupied to see the man in wire-rim glasses watching from across the street.

Discerning Contemporary Approaches towards Effective Education

The pursuit of training, it must be argued, is an activity that brings into perfection the finest essence of human persons. And the reason for this, as I have mentioned in my previous paper, is instead self-evident to engage in discipline or any activity analogous to the purposeful acquisition of knowledge is to nurture the gifts which, at best, summarily evince humanity as creatures cut above the rest i. e. , freewill and rationality (Moore and Bruder 67). Thus, the compulsory importance of creating welcome avenues for learning ineluctably to be considered as a task second to none.At the very least, every last(predicate) human persons atomic number 18, by virtue of their innate superiority, necessitated to constantly strive to create windows of opportunities for higher(prenominal) learning, as well as address ebbs of challenges which, if left unchecked, may end up frustrating the correct methodologies to progressive learning. In view of such felt need, this paper argues for the want of flesh forward-looking goals that can best address the contemporary challenges, which otherwise can pose serious threats to the attainment of quality education.To this end, this study deems it appropriate to limit the handling into unraveling three concrete goals that may be adopted, in the hope of addressing contemporary concerns to education first, to rethink the model of educational Psychology operative on close learning mental hospital second, to subvert schoolroom management towards greater inclusion and participation and third, to re-conceptualize the appreciation of education as that which prep atomic number 18s students for a greater role in the society later on in their otherwise brief lives.It needs to be firstly pointed out however that in itself, education cannot be cut back into these three goals. The human mind, it needs to be argued, is capable of learning many facets of knowledge and as a consequence, the goals with which each learning facet b estows can be taken distinctly from others. For instance, if one were to pursue an education in Engineering, the specific goals with which his or her learning fulfill takes must see through the need to set out ones knowledge of precise mathematical theories on the one hand, and skills relative to concrete application of calculated findings on the other hand.The goal of a person studying Engineering therefore falls more into the acquisition of a knowledge that integrates abstract mathematical theories with concrete skills in fine humanities and drawing. One does not compare such goal with, say educating someone who, while mentally impaired, manifests strains of learning nevertheless. The point in contention here lies in the plain recognition that learning can and must always be construed with its varying goals, depending on the learners frame and chosen field of competency (Ten Dam and Volman 282).Three Forward-Looking Goals It merits firstly arguing that there is a need to rethin k the model of program lineal Psychology operative on many learning institutions nowadays. Herein it would be necessary to cite that there appears to be two major schools of thought beingness adopted into the conduct of present-day education the behavioristic and cognitive paradigms. On the one hand, the behaviorist model of education is most often gleaned on learning strategies that take students as passive learners i. e. , as incorrupt reactors to learning stimuli.The stance, as it were, takes on a highly uninspired understanding of human behavior it takes the mind of a child as a tabula rasa upon which the pith of experience is to be written (Wartofsky 113). On the other hand, the cognitive model of education adopts a paradigm which is exactly the opposite of the behaviorist model. It believes that learning information has to promote the mental abilities already intrinsic to human persons, even before they enter their respective learning places they are mere mental bidd inges that need to be unraveled.When a learner is therefore taken under the acute lenses of cognitive philosophy, the process of developing the unique abilities of abstraction, analysis, cognition, deconstruction, problem solving and self-reflection are the aspects that act as the crux of ones learning. There is, however, a danger in choosing solitary(prenominal) one paradigm to adopt. On the one hand, it is certainly unwise to take learners as though they were programmed to uncritically absorb everything that they are being taught.Learning is not entirely about external influences. On the other hand, it is tinctly self-defeating to bet students as process-induced organisms, without recourse to appreciating their concrete situations. Learning is not completely about internal processes. This is why, it is imperative to rethink the psychological model of facts of lifeal. At best, what appears to be a more promising model to adopt is that which seeks to integrate these twin paradig ms into a comprehensive model for education.Concretely, this can be achieved by taking learners as highly structured organisms, who in their own unique ways, do try to make sense of their life experiences in a manner that is not only dynamic but also constructive (Wartofsky 113). In other words, what Wartofsky correctly notes stems from a keen, if not correct observation that learning is much more than the acquisition of knowledge and the development of innate skills. Learning, instead, brings into fruition ones knowledge and skills, by charting how one is able to successfully apply these concepts into prolific results.Secondly, the telling need to revolutionize the pedagogies and strategies pertinent to effective classroom instruction represents an unmistakably rapidly-growing concern for most educational institutions. At the very least, the old model of traditional instruction needs to be supplanted with better strategies which are now available in the field. Learning, it needs t o be noted, is a delicate process it must be attended to only by acceptable approaches and inviting programs. For such reason, Kounin believes that classroom management is of the essence in the entire learning process i.e. , good classroom management must be considered as an indispensable requisite to students learning (qtd. in Emmer and Stough 104). And there are reasons to think the manner by which educators create and devise appropriate classroom management styles spells the difference between the welcome promotion of learning and the unfortunate frustration of the same. On the one hand, revolutionizing the contemporary approach to learning necessitates a thorough re-evaluation of the technical aspects of classroom management.This re-evaluation process entails, still according to the suggestions of Kounin, putting a fair amount of effort and energy to apply all the three aspects of classroom management into the learning environment first, to ensure that preparations relative to academic programs and campus regulations are properly articulated and clearly outlined so as to facilitate their effective implementation second, to determine head-on whether or not the interaction transpiring between the educator and learners during the actual learning process are marked by appropriateness and facility and third, to determine a program that assesses and monitors how educators are able to control the environment for learning (Vasa 64-66).One may correctly circular that this specific program seeks to guide the learning process before it is undertaken, during its implementation and after the process has been completed. Simply put, the process is comprehensive. And it is with good reasons that a learning institution must adopt such a revolutionary program to guide their respective educational goals and visions into welcome fruition. On the other hand, it has to be likewise comprehended that any effort to revolutionize classroom management cannot stop at ensuring tha t the aforesaid technical aspects work effectively in the service of efficiency and facility. With equal or more emphasis, there is a need to revolutionize, in a manner being drastic but progressive, the fundamental concept of the learning process itself.Herein, it is wise to reminded what P. Freire has to say about the matter i. e. , learning cannot be seen as an asymmetrical process, where teachers dole out incremental nuggets of knowledge and students receive them uncritically as though they were nothing but repositories of data and information. When a learning institution engages in this type of one-way instruction, Freire believes that it adopts an unmistakably restrictive banking concept of education. He believes that under this model, knowledge is (considered as) a gift bestowed by those who consider themselves knowledgeable upon those whom they consider to know nothing (Friere).Instead, Freire maintains that classroom instructions, as indeed the entire process of education, have to revolutionized so as to cater to the need to strive for the emergence of consciousness and critical intervention in reality (Freire). For only when educators see the supreme importance of promoting the learners concrete appropriation of his or her learning can learning environments break free from the traditional spoon-feeding model of instruction that has commodious plagued the many educational systems. Thirdly, there is a certainly a need to re-orient the goal of education in respect to its duty to prepare the learners in subtile their chosen vocations relative the needs of the society later on. Nowadays, education is often seen as a personal ticket to success an instrument which yields a higher rate of success to the top.More and more therefore, the call to recover the thrust of education from this highly individualistic frame becomes even more relevant. As indeed, the need to emphasize the intricate relations between the goals of education and the needs of the societ y cannot be under-appreciated. In ways of more than one, learning is really about participating in the network of relationships latched in humanitys basic sociality. Learning is indeed about the increasing ability to participate in the social and culture practices which are considered important in the society (Ten Dam and Volman 285). And this does not entail seeing the education of students as a precursor their filling up certain stereotyped roles which a society demands.Ten Dam and Volman believes that adequate participation in the society does not mean behaving according to a fixed set of norms, but being able to deal flexibly with the differences and other choices and possibilities (284). Thus, learning is about empowering the students to discover their inner gifts while they are at school so that they can office them for the sake of societys wellbeing later. In the ultimate analysis, it must be recognized that the content of education has indeed something to do with societys n eed for people who are prepared for the conditions of life in a civil society (Daniliuk 13). To briefly conclude, this paper ends with a thought that affirms the abiding necessity of conceiving forward-looking goals to help address the contemporary conduct of education.Time is indeed changing fast and so is the manner by which the world understands education and human learning. In order to adapt, challenges must be met with equivalent responses and adequate solutions. Three concrete suggestions have been raised in this paper to re-conceptualize the model of educational Psychology, to revolutionize classroom management approaches, and to recover the role of education in respect to the needs of the society. Surely, there are still a lot more challenges to hurdle a lot more Goliaths to slay. For the time being, the world can rest assured that for as long as concrete steps are being inclose to address educational issues, there can be little doubt that humanitys can always strive for co nstant learning.ReferencesDaniliuk, A. The Role of Education in the Formation of a Civil Society. Russian Education and Society, 50, 5, 2008.Emmer, E. & Stough, L. Classroom focus A Critical Part of Educational Psychology, with Implications for Teacher Education. Educational Psychologist, 32, 2, 2001.Freire, P. The Banking Concept of Education.Ten Dam, G. & Volman M. Educating for Adulthood or for Citizenship Social Competence as an Educational Goal. European Journal of Education, 42, 2, 2007.Vasa, S. (1984). Classroom Management Selected Overview of Literature. Teacher Education Monograph, 1, pp. 64-74.Wartofsky, M. On the Creation and Transformation of Norms of Human Development. Leonard Cirillo & Seymour Wapner, editors. Value Presuppositions in Theories of Human Development. Hillsdale, New Jersey Lawrence Erlbaum Associates, 1986.

Research on Warehouse Design

European diary of in carrying into action(p) Research 203 (2010) 539549 Contents lists procurable at ScienceDirect European ledger of available Research journal homepage www. elsevier. com/locate/ejor Invited Review Research on store endeavor and effect paygrade 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 composition presents a detailed field of study of the explore on w arhouse convention, exploit evaluation, possible showcase studies, and computational support tools. This and an earlier survey on store store operating theater provide a comprehensive review of existing academic research results in the frame cream of a systematic classi? cation. Each research reach within this framework is discussed, including the identi? cation of the limits of prior research and of potential future research directions. O 2009 Elsevier B. V. All rights containd.Article history Received 5 December 2005 Accepted 21 July 2009 Available online 6 August 2009 Keywords Facilities end and think W arhouse object store performance evaluation simulate Case studies Computational tools 1. Introduction This survey and a swain composition (Gu et al. , 2007) present a comprehensive review of the state-of-art of retentivity terminus store research. Whereas the latter revolve aroundes on w atomic number 18house operation problems related to the four study computer memory warehouse functions, i. e. , receiving, transshipment center, pronounce select, and shipping, this paper concentrates on warehouse visualise, performance evaluation, case studies, and computational support tools.The target areas are to provide an all-inclusive overview of the available orderologies and tools for improving warehouse design holds an d to severalise potential future research directions. store design involves ? ve major lasts as illustrated in Fig. 1 determining the overall warehouse structure sizing and dimensioning the warehouse and its discussion sections determining the detailed layout within each department selecting warehouse equipment and selecting functional strategies. The overall structure (or conceptual design) determines the worldly ? ow exercise within the warehouse, the speci? ation of functional departments, and the ? ow relationships surrounded by departments. The sizing and dimensioning decisions determine the size and dimension of the warehouse as well as the spot al mess among assorted warehouse departments. Department layout is the detailed con? guration within a warehouse department, for example, gangboard con? guration in the recovery area, pallet block-stacking pattern in the reserve repositing area, and con? guration of an Automated Storage/Retrieval System (AS/RS). The equipm ent woof deci* Corresponding author. Tel. +1 404 894 2317 fax +1 404 894 2301. E-mail address marc. emailprotected gatech. edu (M. Goetschalckx). 0377-2217/$ see breast matter O 2009 Elsevier B. V. All rights reserved. doi10. 1016/j. ejor. 2009. 07. 031 sions determine an appropriate automation take for the warehouse, and identify equipment types for terminal, transportation, order select, and sorting. The selection of the operation strategy determines how the warehouse leave be operated, for example, with regards to computer memory and order picking. Operation strategies refer to those decisions about operations that fetch global resolutions on other design decisions, and therefore get to be reck mavind in the design phase.Examples of much(prenominal) operation strategies include the choice between randomised terminal or utilise storehouse, whether or not to do zone picking, and the choice between sort-while-pick or sort afterwards-pick. Detailed operable policie s, much(prenominal) 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 warehouse design decisions are soundly coupled and it is dif? cult to de? ne a lemony terminus ad quem between them. Therefore, our envisiond classi? ation should not be regarded as unique, nor does it imply that whatever(prenominal) of the decisions should be made in arriveently. Furthermore, one should not ignore operational performance measures in the design phase since operational ef? ciency is strongly affected by the design decisions, besides it can be very expensive or impossible to form the design decisions once the warehouse is actually built. Performance evaluation is main(prenominal) for both warehouse design and operation. Assessing the performance of a warehouse in toll of cost, throughput, quadriceps femoris utilization, and service provides feedback about how a speci? design or operational policy performs compared with the urgencys, and how it can be improved. Furthermore, a good performance evaluation pose can serve the designer to quickly treasure m any design alternatives and narrow down the design space during the early design stage. Performance operational cost for each alternative is estimated using impartial uninflected equations. Gray et al. (1992) address a comparable problem, and propose a multi-stage hierarchical approach that uses simple calculations to survey the tradeoffs and prune the design space to a few superior alternatives. computer mannikin is past utilize 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 much(prenominal) as design information collection, design alternative stand upment, and performance evaluation. In compend, published research ndco4h lar02. 8659(wa r,. 0320Td(pro2k evaluation methods include benchmarking, uninflectedal ensamples, and framework amazes.This review forget mainly focus on the former two since simulation results depend greatly on the run throughation details and are less amenable to generalization. However, this should not obscure the fact that simulation is still the well-nigh widely use 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 examp le, 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 think on results published in available English-language research journals. The topic of warehouse location, which is part of the larger area of distri besidesion 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 decisions and future research directions. 2. Warehouse design 2. 1. Overall structure The overall structure (or conceptual design) of a warehouse determ ines 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 slander cost, which may be the discounted honor of investment and future in operation(p) costs. We can identify whole tether published papers addressing overall structural design.Park and Webster (1989) assume the functions are wedded, and select equipment types, storage rules, and order picking policies to minimize derive costs. The initial investment cost and annual J. Gu et al. / European Journal of Operational Research 203 (2010) 539549 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 fabrics include not only warehouse manifestation cost, but also inventory holding and replenishment cost.Levy ( 1974) presents analytic lessons to determine the optimal storage size for a case-by-case 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 positioned as a nonlinear optimisation 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 era 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 rule 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 tapern by Rosenblatt and paradiddle (1988) using simulation. Our ability to answer warehouse sizing psyches 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 ecesis 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 cos ts, 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 optimisation model in Bassan et al. 1980) with a simulation model which evaluates the storage shortage cost, a function of storage capacity and account 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 tenfold 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 talent live octuple departments, e. g. , a forward-reserve con? guration, or opposite storage departments for diff erent 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 studying these tradeoffs in the warehouse area is scarce.Pliskin and Dori (1982) propose a method to compare alternative space parcellings among different warehouse departments ground on multi-attribute honour 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 fulfil the best system performance by appropriately allocating space between these two departments to equilibrium 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 designation of SKUs to the different storage areas as well as the size of each functional area to minimize the total material intervention 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 highroad dept h, tour of passs for each depth, stack height, pallet placement angle with regards to the aisle, storage clearance between pallets, and continuance and width of aisles (P2) storage department layout, i. . , doorsill location, aisle orientation, length and width of aisles, and number of aisles and (P3) AS/RS con? guration, i. e. , dimension of storage bikes, 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 sub rotary 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 stora ge/retrieval operations, considering the SKUs stackability limits, arriving lot sizes, and retrieval patterns. Using deep lane storage could increase space utilization because less 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 items 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) 539549 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) genus 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-establish storage Consider the con? guration of storage bays (unit storage blocks) Consider horizontal and vertical aisle orientations, locations of doors, and regularize of the storage area ground on Bassan et als work with additional costs due to the use of group storage Include not only the ordinary run low clock, but also waiting time when all vehicles are busy The model is solved by vulgarised Lagrange multiplier method Given sea wrack 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 Zollingers rules that consider explicitly operational policies For the design of an automated spinning top system. The model is solved with a simple search algorithm P2 Zollinger (1996) Malmborg (2001) downwind 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 storage ef? ciency and material handling costs by developing analytic models to evaluate the total warehouse volume and the average excursion 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 blend distance are not integrated, and the warehouse layout that maximizes storage ef? ciency is different from the one that minimizes excursion distance. Marsh (1979) uses simulation to evalu ate 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 utilization 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 algori thms, normally 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, nearly 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) 539549 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 storage 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, wh ich 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 system to minimize the initial investment cost and operational costs over a ? ite preparation 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 staple fiber 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. , image 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 mob is extremely rare. Cox (1986) provides a methodology to evaluate different levels of automation based on a cost- productivity analysis technique called the hierarchy of productivity ratios. sporting 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 borderline space design. Matson and tweed (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 stor age 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 intelligent 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 strategi es in a warehouse.The focus is on operation strategies that, once selected, have important effects on the overall system and are not believably to be changed frequently. Examples of such strategies are the decision between randomize and dedicated storage, or the decision to use zone picking. Two major operation strategies are discussed the storage strategy and the order picking strategy. 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 r andom 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 WMSs have this capability. Also the performance of DOS-based policies depends greatly on factors such as the skewness of demands, balance of input and product ? 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) 539549 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 tog ether, 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 tramp picking, i. e. , to release a fraction of the days (shifts) orders, and to expect their picking to be completed within a corresponding fraction of the day (shift). In addition to wave picking, two other usually used orderpicking strategies are batch picking and zone picking.Batch picking involves the assignment of a group of orders to a selector to be picked at the same time 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 wil l 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 complexness 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 workaday 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 mea sures 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 quells a largely clear design problem.Additional research would be valuable, especially if it could begi n 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 importantly, 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 shortco mings 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 research 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) 539549 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. F or 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 locations.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 action (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 F oley 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 distributions 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 deri ve 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 bear travel time models into performance models. Chew and Table 2 Literature of travel time mod els 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) Bozer 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 black rockweed (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) 539549 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 ser vice 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, an d 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 the 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 ca rrying, 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 picking 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 wealth of former results, there is no uni? d approach to travel time modeling or performance modeling for aisle based systems every(prenominal) 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 might conclude from these cases that there are few generic simple rules. As only when 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) 539549 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 imple mentations 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 school computer aided warehouse design and operation systems. Perlmann and Bailey (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 p roduct 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 intensity. 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 computer hardware and software over the past decade.Academic researchers have been at the forefront of computer aided design in 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 s ystems. 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 reflectivity is that only 10% of papers directly addressing warehouse 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 base integrating all the other decisions.The sco pe 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 were, 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 practi ce 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 meaningful expansion and enhancement of warehouse design methodology appears limited.Warehousing is an essential component in any supply chain. 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