Structural and Optical Properties of Pulsed Laser

Structural and Optical Properties of Pulsed Laser Structural and Optical Properties of Pulsed Laser Deposited ZnO/TiO2 and TiO2/ZnO Thin Films R. K. Jain, Praveen K. Jain Abstract. ZnO/TiO2 and TiO2/ZnO thin films have been deposited on single crystal Si (100) substrate using pulsed laser deposition (PLD) technique in order to improve structural and optical properties of ZnO and TiO2 thin films. It was observed that the deposition of TiO2 film prior to ZnO, exhibited higher crystallinity along (002) diffraction peak, small compressive strain and stress and thereby rendering better optical properties as compared to ZnO films deposited directly on Si substrates. On the other hand, TiO2 thin film deposited on Si substrate exhibited pure anatase phase while the use of ZnO buffer was found to improve the crystallinity of TiO2 thin film. The photoluminescence spectra showed that TiO2 and ZnO buffer layers enhanced ultraviolet emissions of the ZnO and TiO2 thin films to a larger extent, respectively. Keywords: ZnO, TiO2, Optical properties, Photoluminescence PACS: 78.66.Hf, 78.55.Et, 68.37.Ps Introduction ZnO is suitable for the production of light emitting devices and a promising candidate for the next generation of electronic devicesdue to its wide band gap (3.37 eV) and large exciton binding energy (60 meV)[1]. ZnO thin films play an important role in solid-state display devices, solar cells and exciting acoustic waves at microwave frequencies[2]. Titanium dioxide (TiO2) is one of the most important semiconductors with high photocatalytic activity, non-toxicity, stability in aqueous solution, and is relatively inexpensive. The excellent photocatalytic property of TiO2 is due to its wide band gap and long lifetime of photogenerated holes and electrons [3-4]. It has been reported that the deposition of ZnO or TiO2 thin films on Si substrates at elevated temperature leads to increase in oxygen vacancies as the surface Si atoms easily capture oxygen atom from ZnO or TiO2, which deteriorates the quality of the these films [5]. So it is required to improve various properties of ZnO and T iO2 films for their potential applications. In the present study, a systematic investigation has been performed in order to improve the structural and optical properties of these films using buffer layers. ZnO and TiO2 are chosen as a buffer layer material on the basis of following considerations: (a) Both are wide-band-gap materials, (b) both exhibit high chemical and thermal stability, (c) both have high refractive indices, high transmittance in the visible region and intense absorption in the ultraviolet band and (d) both are low cost material. EXPERIMENTAL DETAILs ZnO and TiO2 thin films have been deposited on Si (100) substrate by ablating high purity (99.9%) ZnO and TiO2 ceramic target using pulsed laser deposition (PLD) technique. The KrF excimer laser with wavelength of 248 nm was used for deposition. The pulse repetition rate was 10Hz with laser fluence of about 2–3Jcm−2. The target to substrate distance, working O2 pressure and deposition temperature were kept 35mm, 50 mTorr, and 500Â °C respectively. The thickness of the film and buffer layer was measured using cross section FE-SEM and found to be ~200 nm and 50 nm, respectively. The phase and orientation of as-grown thin films were characterized by X-ray diffractometry (Bruker AXS D-8 Advance Diffarctometer) using CuKÃŽ ± (ÃŽ »=1.5407 Ã…) radiation. The surface morphology was examined using atomic force microscope (NTMDT: NTEGRA model). Absorption spectra have been taken using UV-VIS-NIR spectrophotometer (Varian Cary 5000) and PL study was performed using photolumines cence spectrometer (Perkin Almer LS-55). RESULTS AND DISCUSSION XRD pattern reveled that ZnO thin film grown on Si (100) substrate was preferentially oriented along the c-axis with a hexagonal wurtzite structure and the use of TiO2 buffer layer increases crystallinity along (002) diffraction peak as shown in Figure 1. On the other hand, TiO2 thin film exhibit pure anatase phase and crystallinity was improved along (004) plane by inserting the ZnO buffer layer between substrate and TiO2 thin film. The improved crystallinity of thin film using buffer layer resulted from the mismatch in thermal expansion coefficient between ZnO and TiO2, which is smaller than that of between ZnO and Si or TiO2 and Si. The lattice mismatch between ZnO and Si (1 0 0) are 40%, whereas for their counterparts i.e. between ZnO and anatase-structured TiO2 are 14% [6]. Therefore, the decrease of lattice mismatch is another reason for the improved crystallinity. The crystallite size calculated using Scherer’s formula is shown in Table 1. The strain along the c axis, zz is given by the following equation [7]: (1) where c is the lattice parameter of the strained ZnO films calculated from x-ray diffraction data and c0 is the unstrained lattice parameter of ZnO. The lattice mismatch between film and substrates can result in varying degrees of stress during the growth process of thin films. The results show that the compressive strain is present in all fabricated ZnO and TiO2 films, which is derived from lattice mismatch between substrates and films owing to increase in crystallite size, and the stress is decreased with the buffer layer. Figure 2 shows the AFM image of the deposited thin films. The grain size and average surface roughness increases when buffer layer is used due to enhancement in crystallinity. Figure 3 shows the room temperature PL spectra of ZnO and TiO2 thin films grown on Si substrate with and without buffer layer. The ZnO film deposited on Si (100) substrate exhibits strong ultraviolet emission peak along with weak green–yellow emission band. The ultraviolet emission of ZnO films is generally considered to be resulted from recombination of free exciton, whereas the green emission is mainly resulting from oxygen vacancies [8]. The PL spectra of TiO2 thin film deposited on Si (100) substrate shows a broad emission band from 390 to 450nm and there are two emission peaks superimposed on the broad emission band. The peak before 350nm (~3.5eV) is ascribed to direct electron-hole recombination which should be equal to or slightly bigger than the TiO2band gap. The emission band from 390 to 450nm (corresponding to 3.2–2.75eV) arises from indirect band gap and surface recombination processes. Further observation indicates that there are two small peaks at the wavel ength range from 460 to 500 nm. These PL signals are attributed to excitonic PL, which mainly result from surface oxygen vacancies and defects of the films. It is observed that ZnO thin film deposited on the TiO2 buffer layer shows stronger ultraviolet emission, as compared to ZnO thin film grown without buffer layer, with no visible emission. The absence of visible emission shows the defect free formation of film. Similarly, the use of ZnO buffer layer also removes the oxygen defects emission peak of TiO2 thin film. The enhanced ultraviolet emission from ZnO thin films grown on TiO2 buffer layer is also probably connected with fluorescence resonance energy transfer (FRET) between ZnO and TiO2. After the excitation of electron–hole pairs in TiO2 layer, the energy is easily transferred to ZnO films due to resonance effect [9] as a result, the band gap emission of ZnO is enhanced. From optical absorption spectra of ZnO and TiO2 thin films, It is observed that ultraviolet absorption edge of ZnO and TiO2 film with buffer layer has a red-shift, compared with ZnO and TiO2 thin film grown on bare Si (100) substrate. The value of direct band gap was found to be 3.29 and 3.24 eV for ZnO thin films grown on Si substrate without and with TiO2 buffer layer, respectively. On the other hand, the value of indirect band gap was found to be 3.24 and 3.19 eV for TiO2 thin films deposited on Si (100) substrate without and with ZnO buffer layer. The decrease in optical band gap of the films could be related to the enhancement in crystallite (grain) size leading to a smaller number of grain boundaries. On the other hand the compressed lattice will provide a wider band gap because of the increased repulsion between the oxygen 2p and the zinc 4s bands [10]. CONCLUSISON ZnO, TiO2, ZnO/TiO2 and TiO2/ZnO thin films on Si (100) substrate were prepared by pulsed laser deposition technique. XRD and AFM result demonstrate that the crystallinity of ZnO and TiO2 thin films are considerably improved by using TiO2 and ZnO buffer layer, respectively. Compared with PL of ZnO thin film, UV intensity of ZnO grown on TiO2 buffer layer has increased about two fold. Similarly, the ZnO buffer layer improved the UV emission of TiO2 thin film. The band gap of ZnO and TiO2 thin film grown on buffer layer found to decrease due to improved crystallinity. REFERENCES [1] X. Teng, H. Fan, S. Pan, C. Ye, G. Li, Materials Letters 61 (2007) 201–204. [2] G. C. Yi, C. R. Wang, W. I. Park, Semicond. Sci. Technol 20 (2005) S22. [3]X. Zhang, F. Zhang, K. Y. Chan, Material Chemistry Physics 97 (2006) 384. [4]A. B. Bodade, A. M. Bende, G. N. Chaudhari, Vaccum 82 (2008) 588. [5] X. M. Fan, J. S. Lian, Z. X. Guo, H. J. Lu, Appl. Surf. Sci. 239 (2005) 176 [6] L. Xu, L. Shi , X. Li , Applied Surface Science 255 (2008) 3230–3234 [7] H. C. Ong, A. X. E. Zhu, and G. T. Du, Applied Physics Letter 80 (2002) 941. [8] Y. Zhang, B. Lin, Z. Fu, C. Liu, W. Han, Optical Materials 28 (2006) 1192. [9] H.Y. Lin, Y. Y. Chou, C. L. Cheng, Y. F. Chen, Optical Express 15 (2007) 13832. [10] R. Ghosh, D. Basak, S. Fujihara, Journal Applied Physics 96 (2004) 2689.

Divisibility Argument :: essays research papers

DIVISIBILITY ARGUMENT This paper will discuss the dualism’s Divisibility Argument. This argument relies on Leibniz’s Law and uses a different property to prove the distinctness of brain states of mental states. Mary, who is a materialist, presents several objections to that argument. Her main objection corresponds to the first/third-person approach. She believes that Dave presents that argument only from the first-person approach, which is introspection, and totally disregards the third-person approach, which is observation of another mind. Mary’s objections will follow by the Dave’s response on them from the dualist’s point of view. The purpose of the Divisibility Argument is to prove that mental states are different from the brain states. My body, which includes my brain, is divisible. However, I cannot conceive of my mind as divisible. Therefore, my mind is distinct from any part of my body. Descartes was the first who established the Divisibility Argument. He held that the two components which constitute man had an independent origin and are of a fundamentally different nature. The body is divisible, since it can be separated for example, my leg or my hand can be cut off; my brain can be cut on half. However, the idea of the divisible mind is inconceivable. This argument relies on the Leibniz’s Law. It is a principle about identity, which says, â€Å"if an object or event X is identical with an object or event Y, then X and Y have all of the same properties.† So if X and Y have any different properties, then X can not be identical with Y. Divisibility Argument uses a different property to prove the distinctness of brain states and mental states: the property of being indivisible. In this case, the mind has a property and brain lacks it. The body can be divided, however, it cannot be done with the mind. Mary has several objections to this argument. First, she believes that the mind is an entity, which is composed of several mental states: thoughts, beliefs, memories, desires, etc. Mary strongly disagrees with Descartes’ claim that the mind employs itself in its different properties: willing, desiring, understanding, and so on. Secondly, she clarifies the meaning of the word â€Å"conceive† in the Dave’s argument. The term â€Å"conceive† might mean either â€Å"imagine† or â€Å"understand.† Imagining literally involves â€Å"forming an image of† or â€Å"picturing† in one’s mind, whereas understanding is more â€Å"conceptual† and does not require the ability to picture something.

Danger Underground: Nuclear Waste Disposal in Yucca Mountain Essay

Danger Underground: Nuclear Waste Disposal in Yucca Mountain Introduction The U.S. Department of Energy has proposed plans to deposit 70,000 tons of highly radioactive waste underground Yucca Mountain in Nevada. While many environmental questions and concerns have been raised about the safety of the waste disposal plan for the next 10,000 years, there appears to be no alternative. Waste from nuclear weapons and nuclear power plants are a serious environmental problem that will be present for generations to come. It should be society's responsibility to come up with more efficient sources of energy, despite the costs, to prevent the production of more hazardous waste in the future. The "nuclear age" produced 52,000 tons of spent fuel from commercial, military, and research reactors, along with 91 million gallons of radioactive waste from plutonium processing (Long 12). More than 90% of the waste that needs to be stored is from commercial nuclear power plants, and 10% is from defense programs (Environmental Protection Agency/ Yucca Mtn. Standards). The waste from defense programs primarily accumulated during the arms race of the Cold War. Waste produced from commercial nuclear power plants is currently stored in 131 separate facilities in 43 different states, most of which are east of the Mississippi (Wheelwright 2002). Several government departments are responsible for taking care of all this waste. The Department of Energy (DOE) runs the nuclear facilities and supervises cleanup performed by commercial contractors. The Environmental Protection Agency (EPA) is responsible for setting health and environmental waste standards for the long-term storage of waste produced by these facilities. The Department of Transportati... ... 2002. www.sacredland.org/yucca_mountain.html The Yucca Mountain Project. 2002. Referenced on 7 October 2002. www.ymp.gov/ U.S. Department of Energy: Office of Energy Efficiency and Renewable Energy. 2002. Referenced on 11 Nov. 2002. www.eren.doe.gov/RE/solar.html U.S. Environmental Protection Agency/ Yucca Mtn. Standards. 2002. Referenced on 7 October 2002. www.epa.gov/radiation/yucca/about.htm Watson, Roland. "Nevada Outraged by Eternal Dump for Nuclear Waste." The Times 24 Sept. 2002 Newspaper Source. Palni Site Search. Goshen College Good Library. 7 Oct. 2002. Wheelright, Jeff. "Once There Was A Mountain in the Desert of Nevada." Discover 23 (Sept. 2002): 66-76. Academic Search Elite. Palni Site Search. Goshen College Good Library. 3 Nov.2002. Why Not Yucca Mountain? 2002. Referenced on 7 October 2002. www.nvantinuclear.org/

Plague - Bacillus Yersinia Pestis Essay -- Biology Medical Biomedical

Identification and Prevention of What Makes Life â€Å"Nasty, Brutish, and Short† Plague is caused by the bacterium bacillus Yersinia pestis, and is carried by rodents, fleas, and mammals. Plague takes three forms: bubonic, pneumonic, and septicemic. Bubonic plague affects the lymph glands, while the pneumonic and septicemic forms affect the lungs and the blood. Today, plague can be prevented by antibiotics and strict public health measures. Three methods of controlling carriers involve sanitizing the environment, educating the public on how to prevent exposure, and using prophylactic antibiotics. â€Å"O happy posterity, who will not experience such abysmal woe and will look upon our testimony as a fable,† wrote the Florentian Renaissance author Francesco Petrarch to a friend in the midst of the Black Plague (Benedictow 3). Indeed, the Black Plague and its timeless infamy define when life was nasty, brutish, and short. Between 1346 and 1353, the Black Plague cast its dismal shadow over Europe, North Africa, the Middle East, and Western Asia. The plague also recurred in the late 19th and early 20th centuries in huge pandemics in Asia, and continues to be a threat today. The agent of plague, the bacterium bacillus Yersinia pestis, is transmitted to humans through the bite of infected fleas. Yersinia pestis is carried in the circulatory systems of chipmunks, prairie dogs, ground squirrels, mice, and other mammals. The plague is spread among humans by the inhalation of coughs of plague pneumonia. Although it is tempting to dismiss this pathogen as only active in outbreaks like the Black Death, and despite that the medical community found solutions to plague, plague continues to threaten those who live in areas of poor housing and sanitati... ...f Person-to-Person Transmission of Pneumonic Plague.† Healthcare Epidemiology. 27 July, 2006. 15 April, 2005. . Kopp, Elizabeth, and Medzhitov, Ruslan. â€Å"A Plague on Host Defense.† The Journal of Experimental Medicine. . â€Å"Plague Fact Sheet.† Centers for Disease Control and Prevention. Department of Health and Human Services. 30 March, 2005. 26 July, 2006. . â€Å"Plague Prevention and Control.† Centers for Disease Control and Prevention. Department of Health and Human Services. 30 March, 2005. 26 July, 2006. . VeriMed Healthcare Network. â€Å"Plague.† Medline Plus. 17 June, 2005. 26 July, 2006. .

Masculinity and World War Ii

Masculinity and World War II The image of Man has changed throughout time. Dominant constructions of masculinity, which are basically attempts to stabilize gender identity, are developed within the dynamics of shifting cultures and societies. The male stereotype, which is still prevails nowadays, started rising at the end of eighteenth – beginning nineteenth century in Europe with a great concentration on the male’s body. The stereotype made the world look at man more like a type rather than an individual.Masculinity was strengthened due to the positive stereotyping, however for those that did not conform to this label or fit in with the ideal, were negatively stereotyped. Being an outsider who was born in a different country made it especially interesting to penetrate the American culture and research about American masculinity. Truly, much of the progress of any country has been defined around the lives and accomplishments of great men. One cannot begin understanding the history of America without understanding manhood and the influence of the male. In every generation in America, manhood has been in the center of life and progress.It constantly strives to uphold its own traditions while trying to redefine itself. I have done a lot of research about American masculinity and how it has been changed throughout the history. While going through different literature about the nature of masculinity, I came to the conclusion that for many men, the idea of masculinity is deeply tied to military prowess and adventure. One cannot but agree that war, the most violent and decisive of human acts, is the paradigmatic masculine enterprise. Military service is one of the rites of manhood; it makes men men.Moreover, war makes nations masculine, too. This paper examines the nature of masculinity and the role of masculinity in America. My main focus is on the changes in definitions of masculinity during the WWII Era and goes on to discuss the psychological and emo tional effects of the war and the subsequent readjustment efforts in the same era. In this work I will try to explore different author’s conclusions about masculinity, its changes and/or problems during the WWII and in its post-period. War, more than any other action, offers the ultimate test and demonstration of manhood.Indeed, it has been suggested that the sole cause of war is masculinity. War requires masculine energy and communal effort. It engages man in the age-old conflict between courage cowardice, right and wrong, aggression and compassion. In his book Manhood in America: A Cultural History, Michael Kimmel concentrates his attention on a large set of questions about the importance of masculinity: â€Å"I do believe that a comprehensive historical account of the American experience can no longer ignore the importance of masculinity – and especially of men’s efforts to prove their manhood – in the making of America† (5).For the soldier who fought during the WWII, the country conveyed upon him the gift of manhood. It was a war which redefined American masculinity. Although it led men to brutality on a very personal level, it served the hero archetype well. To embody courage under the most gruesome circumstances, the soldier has to repress his fear. To embody strength, he had to repress his feelings of vulnerability. In fact, what war required is manliness: â€Å"The men who were the best soldiers were, in effect, the best men† (Gagen 23).Elizabeth A. Gagen in her article â€Å"Homespun Manhood and the War Against Masculinity: Community Leisure on the US home front, 1917-19,† discussing the war and its influence on masculinity, states that â€Å"military masculinity became more entrenched in myths of heroism as sacrifice as citizenship was masculinised and masculinity was militarized† (27). Even though the author’s concentration is mostly on the WW I, Ganger discusses a lot about masculinity and the effect of wars on American cultures.Gagen locates the early-century crisis of masculinity in the loss of control men were experiencing: the authority of white, middle-class men was being threatened by the increasing presence of women in the public sphere. While on the one hand it was great opportunity for economic success, it also destabilized traditional gender and class hierarchy. All this placed a lot of pressure on the soul of American manhood. As it started happening, across America men returned to an increasingly protected wilderness in the hope that rehearsing primitive blood sports might revive in them their primal instincts.As Ganger goes on, she brings a very interesting point of view, where she connects the image of fighter with the image of hero and explains the men’s necessity to participate in the war: While blood sports and boxing could go some way towards providing a satisfactory venue for cultivating masculinity, there was something peculiar to war th at was uniquely desirable. When all around them masculinity seemed to be failing, war appeared as the last frontier of manliness: a crucible in which masculinity could be reborn. (27) A military service man was not just an aggressive heroic individual, he was a unique blend of masculinity.Therefore, for American man the war became a great opportunity to show their aggression, strength, courage and endurance. All these are the qualities of manhood. Similar to Gagen, Christina Jarvis, a psychologist and a professor at the State University of New York, in her discourse â€Å"If He Comes Home Nervous: U. S. World War II Neuropsychiatric Casualties and Post War Masculinities,† illustrates the traditional masculinity ideology. She uses the analogy of medieval knightly chivalric code. The chivalric code was the guiding principle that highlighted the designated features of medieval warrior class as unyielding, heroic, and tough.The chivalric code, as Jarvis notes, would in turn have a significant influence in developing the ideals of traditional masculinity in the earlier 20th Century World War years. During the same period, the perceived notion of masculinity gender superiority was prevalent in then overly patriarchal society that existed at that time. The society depicted military masculinity as invincible. The common notion was that since men are physically more capable than women are and that only the toughest got into the military, then masculinity ultimately surpassed shallow emotional vulnerability.The United States came out of the conflict viewing itself as a masculine nation. The postwar generation of American men grew up revering a hero image, but, as it turned out, there was one major problem. The heroes too often didn’t see everything the same way as the other people did. What they brought back from the war were oppressive memories that wouldn’t go away. What they brought back from the war was emotional trauma and enormous challenges i n reintegrating with domestic life. While they were recruiting in anticipation of war, American soldiers trained vigorously pledging their undying dedication to protect and defend their country.Jarvis asserts that it was a sacred duty for all soldiers to uphold bravery, resilience and courage, which were among the core military ideals. As it turned out, the perceived masculinity resilience ideal was actually overrated. Besides sustaining bodily and physical harm in the course of the war, American servicemen apprehended severe psychiatric and emotional injury as well. These soldiers witnessed atrocities and inhumane acts of war and saw the physical torture of many as well as demise of others in the battlefield.This in turn caused some of them to apprehend psychiatric harm in form of Post Traumatic Stress Disorder. Similarly, the servicemen who sustained severe bodily harm that left them physically handicapped suffered from acute mental and emotional disorders. As such, physical and m ental injuries are inseparable. As Christian Hoge in his work â€Å"Combat Duty in Iraq and Afghanistan, Mental Health Problems, and Barriers to Care† explains, the course of World War II altered the preconceived notion that masculinity was beyond emotional vulnerability.In his discourse on mental harm during the World Wars and the Iraqi war on terror, Hoge asserts that the war shattered the spirit of American soldiers given that they had to watch their helpless colleagues die of intensive injuries, disease and starvation. Some lost close friends and relatives in the event of war. This, as a result, undermined the traditional masculinity ideals while people began to appreciate that despite their bravery, soldiers were human beings with emotions and feelings and not as invincible as everybody initially thought. Numerous soldiers came under immense stress while in the battlefield.Some of them began to re-evaluate their dedication to defend the integrity of their country amid a situation where it seemed that everyone had forsaken them. At this point, fighting for personal survival went beyond defending the national integrity. The war exposed the emotional dimension of men as they began worrying about their families back at home and the hitherto ardent masculinity ideology began to wither. As soon as the mainstream news periodicals reported on the psychological harm imposed on soldiers by the war, literary advice in form of medical opinions on remasculinisation of war veterans began to emerge in late 1944.In his discourse on the early years post-war scenario When Johnny Comes Marching Home, David Wecter wrote that â€Å"the rebuilding of a war neurotic, sent home for treatment, must begin by convincing him that he is not a coward or a failure, but a battle casualty just as truly as the man who lost a leg† (547). His sentiments reflected the mainstream thoughts of the American people at the time. There was a widespread public outcry concerning the psy chological welfare of the soldiers who had dedicated their unrelenting efforts to preserve the integrity of America. Jarvis in her work depicts the same problem soldiers faced during and after war.But, she states that early in the war, soldiers and sailors who â€Å"broke down† under the pressure of combat or military life were generally discharged instead of treated. According to military psychiatrists Malcolm Farrel and John Appel, as Jarvis goes on , â€Å"these early discharges stemmed from the idea that initially the military thought it was possible to contemplate an Army made up of the cream of American manhood† (100). Given the military’s initial assumptions that only servicemen with weak egos broke down, early psychiatric casualties were stigmatized – especially when soldiers were labeled as â€Å"psychoneurotic. This term associated with both the â€Å"feminine† and â€Å"insane. † As a result the armed forces began a program of pr ompt treatment. The term â€Å"combat exhaustion† has been invented by psychiatrists: Despite the fact that labels such as â€Å"battle fatigue,† â€Å"combat exhaustion,† and â€Å"old sergeant syndrome† actually represented approximately one quarter of the war’s total neuropsychiatric admissions, military personnel and the public readily embraced the terms because they destigmatized psychiatric wounds by conveying a sense of masculine toughness rather than weakness. 101) Seeing as the traditional masculinity ideology had significantly shrivelled in the course of WWII, America dedicated its efforts towards a physical and psychological readjustment cause. Apart from the provision of intensive care for the psychiatric casualties, America’s special medical consultants sought to de-stigmatize psychiatric conditions. Psychiatrist George Pratt in his book Soldier to Civilian: Problems of Readjustment reassures the casualties that the term psychia try does not necessarily connote insanity.He says that on the contrary, the terms psychiatry and neurology as used in this post-war context implied â€Å"a departure from average personality traits or temperament †¦ that render a soldier unsuitable for military service† (14). In bid to clarify the paradigm shift and divergence of the post war psychological discourses, Pratt explains that these psychiatric discharges resulted from what he terms ‘situational stressors’ and not due to flawed personality or ego.Pratt’s efforts in de-stigmatizing psychiatric war injuries oversaw a rapid psychological recovery of the casualties. He notes as well that the condition was in all likelihood temporary save for a few cases of acute neuropsychiatric disturbances. Through his profound medical expertise, Pratt recommends the post war psychiatric casualties to share their war experiences with their families as well as medical experts.He reckoned that this would help i n the gradual healing process and the ultimate restoration of the traditional masculinity ideals. What we know about manhood and masculinity now gives us an extraordinary opportunity to become relevant in our own time. The old models of manhood provide a too-limiting definition for the complex sense of manliness. As we can see through examples from history, men are more than just unemotional beasts, who are ready to die for their nation and their country any time they are needed.Man can be a soldier, man can be a warrior. No matter in what situation the society puts our men, we shouldn’t forget that they are just human beings and nothing human is alien to them. It might sound very sad but the war in some way helped a soldier to figure out what true manliness is. One of the friends of Jess, who is the main character of the book Stone Butch Blues by Leslie Feinberg, once said that everyone gets scared once there is a danger, but to be courageous means to go ahead in spite of be ing scared.Men should realize that for all of us they are already heroes because they didn’t hesitate to go and fight for their country and their people. Manhood and masculinity in America are expressions of many different ideas and sentiments. This review touched the idea that there is no single definition of man. And war, as one of the most important factors, showed us how far away from the reality the society’s prospective about masculinity might be.

The Fundamentals of Entrepreneurship: The American Dream

I have always been fascinated by the concept of the â€Å"American Dream†. Even if, nowadays, this concept is more and more criticize because some people believe that the structure of American society doesn’t follow anymore the idealistic goal of the â€Å"American Dream†, providing example such as inequality in class or race which suggest that the â€Å"American Dream† is not attainable for all. But to me the term â€Å"American Dream† stays unchanged: all people can succeed through hard work, and all people have the potential to live happy and successful lives. And in my mind, the entrepreneurship is one of the most famous way to achieve this â€Å"American Dream†. Steven BUYERS who is the founder and owner of EnergyLogic –a fast-growing company in Northern Colorado, appears to me as a very good example of this â€Å"American Dream† which is about hope and the potential for change. In fact, I feel this at the same time through the very innovative and sustainable development oriented concept of his company, and the take of initiative he seems able to show without having a precise idea of where it will lead him. In this paper, I’m going to discuss two major topics which seems relevant to me given Steven BUYERS’ experience, they are: the self-made man and the capacity to see opportunity. Self-made man The first thing I would like to precise is about the vision I have of a self-made man. Obviously when I use this term I’m not saying that Steven BUYERS is the only one responsible of the success of his company, because it would mean that nobody have accompanied him in this project and it wouldn’t be fair not to think about his employees or his wife who has apparently plays a huge role in his success. But I rather mean that he had managed to create and manage a success business starting from like nothing. The concept of the self-made man is necessarily connected with the â€Å"American dream† that I have mentioned before. The self-made man comes from unpromising circumstances, is not born into privilege and wealth, and manages to become a great success in life by his own efforts. The story of the self-made man embodies the goal of every man: â€Å"to become the captain of his own destiny. Actually this is really close to the reasons that people become entrepreneurs and starts their own firms, that is to say: â€Å"be their own boss, pursue their own ideas and pursue financial rewards. † A self-made man is anyone who attains far greater success which was not predictable. The background that Steven BUYERS told us about isn’t exactly what we can call a â€Å"predestinated background†. Indeed, he went through many different jobs and life’s experiences (from the army to a bookstore) before he found his way which tends to prove us that he is one of whose are able to create their own greatness. Finally I would say that being a self-made man, as being an entrepreneurship, is the result of a difference in your character and a willingness to do whatever it takes to be the best and achieve your dreams, just as the concessions made by Steven BUYERS at the beginning of his project. Capacity to see opportunity â€Å"An opportunity is a favorable set of circumstances that creates a need for a new product, service or business. † When we know that homes represent 20% of the energy use in USA –whereas transport â€Å"only† represents 27%, it appears logical to focus on this problem. But at the time that Steven BUYERS started his business, that is to say in 1998, nobody cared about saving energy. He came with this really simple question: â€Å"How to be more efficient with houses’ energy? †, and his project was to provide people with a solution. As far as the opportunity recognition is concerned, Steven BUYERS has done a really good job. Indeed, he identified a product/service that people need and are willing to buy. Everybody isn’t able to see opportunity, because opportunity isn’t just an idea you come with thinking it could work. And this is a crucial point which will determine if the business is going to work, or not. An opportunity has to perform four essential qualities: attractive, durable, timely and anchored to a product. That was the case for Steven’s idea. It was attractive because it allows people to save money; it was durable because it lasts a life-time; it was timely because sustainable development was beginning to develop; and finally it was anchored to a product because it deals with houses and isolation. What is even more impressive in this recognition of opportunity is that Steven BUYERS hasn’t done any real market study or business plan before launching his company. To me the way to identify an opportunity which fit the best to Steven BUYERS is the personal characteristics of entrepreneur. This capacity to see opportunity is an essential trait in my mind which is related to creativity. To conclude I would cite the philosopher Ralph Waldo Emerson: â€Å"Do not go where the path may lead, go instead where there is no path and leave a trail. † Being an entrepreneur means being able to go where nobody else went before you, being able to take risks, being able to see opportunities where nobody has looked before you†¦ In my mind there is different ways to succeed in your job. Steven BUYERS succeed by seeing opportunities and managing his own success story as many self-made men have done before him. But no matter what is your background as far as you take your chance to develop successfully your business idea. Unfortunately, nowadays, entrepreneurs are more and more assimilated to capitalism and all the unfairness it can raise. As a result, famous self-made men such as Rockefeller are not as well-recognized as they were in the past –and sometimes even criticized. So we can wonder if the â€Å"American Dream† is still an example to follow or a goal to reach for the majority of American people.

Improve Efficiency Essay

A very high percentage of the items selected (picked) in the distribution centers and re-stocked in the stores were in quantities of 1 case. This company’s roots were as a high volume, limited assortment retailer and distributor. Over time the business had shifted allowing the stores to reorder a higher mix of items at lower volumes. Given the companies market position as a low-price leader, this reduced profit margins. The two root causes of this shift were identified as: 1. Stock-keeping-unit (SKU) count growth outpacing sales growth, and 2. Allowing minimum order quantities from the stores to the distribution centers to drop to a quantity of one This white paper will study how this company quantified the impact of allowing its stores to order in one case quantity and then recalculated minimum order quantities for higher volume items. (For details of how SKUs were reduced see White Paper â€Å"SKU Reduction – Biggest SKLUsers†) A Supply Velocity Consultant led a team of employees through this 5 week project. The Supply Velocity consultant facilitated, but the employees did most of the analysis and therefore owned the improvements. nfo@supplyvelocity. com Copyright: Supply Velocity, Inc. 2 Project Outline ? Evaluated all SKUs and the case quantity they are most frequently ordered at, to establish baseline data for how stores are ordering ? Time studied retail store shelf restocking and distribution center order selection labor to determine the negative labor productivity impact of the current ordering policy o Graphed the results in a trend chart o Determined that the greatest labor productivity improvement happens when the order quantity increases from just 1 to 2 cases ? Recalculated minimum order quantity for all items using Multi-Variable Pareto analysis based on: o Item unit movement o Pack-out (number of units that fit on the shelf space allocated in stores) o Shelf life ? About 20% of all SKUs had a re-calculated minimum order quantity greater than 1 case o The most conservative methods were used to ensure this project didn’t just push inventory out to stores, resulting in shrink (throwing away items that go beyond their shelf-life limit or are damaged) ? Communicated all items on the minimum order quantity to all stores through a comprehensive communication plan o Communication plan included data to show stores how increasing minimum order quantity on select items would improve their labor productivity ? Created a control plan to ensure new items, SKU reduction and sales history will be used to update the minimum order quantity on a twice yearly basis info@supplyvelocity. com Copyright: Supply Velocity, Inc. 3 Time Study Analysis To quantify the problem, we time studied order selection in the distribution centers and shelf restocking in retail stores. We conducted a few snapshot analyses of different distribution centers to understand the current state of â€Å"order quantities†. The graph below shows that out of the approximately 2800 items, a majority are ordered in quantities of 1 case. The time study data also showed that the second case selected or stocked is essentially â€Å"free† and the same movement is used for two cases as for one case. At the outset of this project the team was worried that any increase in minimum order quantity would be viewed by store managers as an attempt to push inventory out from the distribution centers to the stores. This data showed that increasing minimum order quantity from one case to just two, gave us the greatest percentage of labor productivity improvement. However, we didn’t just want to increase all items to a 2 case minimum order quantity. Instead, a statistical tool, Multi-Variable Pareto was used to calculate the proper minimum order quantity based on a mix of inputs. nfo@supplyvelocity. com Copyright: Supply Velocity, Inc. 4 Distribution Center Order Selection Quantity (# of items picked per quantity) 57% of the items in distribution centers were selected at a 1 case quantity info@supplyvelocity. com Copyright: Supply Velocity, Inc. 5 â€Å"Time to Select per Case Quantity† in the Distribution Centers – Based on case count per selection When selecting 2 cas es of an item, the time per case drops by 45% from 1 case. info@supplyvelocity. com Copyright: Supply Velocity, Inc. 6 Time to Re-Stock SKUs on Shelves in Stores – Based on case count When restocking 2 cases of an item, the time per case drops by 61% from 1 case. This shows that the greatest productivity improvement occurs when going from 1 to 2 cases, which is easier to â€Å"sell† to the stores than making large increases in minimum order quantity. They can reduce labor by 37 seconds per case by ordering and stocking 2 cases of an item versus 1. info@supplyvelocity. com Copyright: Supply Velocity, Inc. 7 Multi Variable Pareto Analysis ? Recalculated minimum order quantity for all items using Multi-Variable Pareto analysis based on: o Item unit movement o Pack-out (number of units that fit on the shelf space allocated in stores) o Shelf life ? About 20% of all SKUs had a re-calculated minimum order quantity greater than 1 case o The most conservative methods were used to ensure this project didn’t just push inventory out to stores, resulting in shrink Multi-Variable Pareto is a method that uses more than one â€Å"measure† to sort SKUs from highest to lowest performing. Normal Pareto Analysis has been used to develop guidelines such as the 80/20 rule (20% of customers generate 80% of sales). When using multiple variables, there has to be a way to normalize the data so all variables are part of the analysis. We used three variables to determine the correct minimum order quantity for an item. ? Cases sold per week on average for each item ? The number of cases that fit in the given shelf space ? Product shelf-life Each of these variables are positively correlated to Minimum Order Quantity. ? The higher the cases sold equals higher Order Quantity ? The greater the shelf space (pack-out) equals higher Order Quantity ? The longer the item’s shelf-life equals higher Order Quantity The team of subject matter experts used retail experience to determine each of these factors and their impact on minimum order quantity. Results of this analysis are shown below. The calculation was very conservative, as the results have shown. Only 466 of 2800 items have a minimum order quantity greater than 1 case. This was largely driven by two factors. Item shelf-life limited our ability to make any shelf-life sensitive item greater than 1 case. Our calculation took this limiting factor into account, to ensure we weren’t causing shrink (throwing away items that go beyond their shelf-life limit or are damaged) at the stores. In addition, lower case movement drove many items to a 1 case minimum, even if they didn’t have shelf life limitations. The lower case movement is due to SKU proliferation and was addressed by the SKU Reduction (Biggest SKLUsers) project. info@supplyvelocity. com Copyright: Supply Velocity, Inc. 8 Results of Minimum Order Quantity Calculation info@supplyvelocity. om Copyright: Supply Velocity, Inc. 9 Communication & Control Plan ? Communicated with all retail stores about how the minimum order quantity analysis was conducted and the resulting new plan o Communication plan included data to show stores that increasing minimum order quantity on select items would improve their labor productivity ? Created a control plan so new items, SKU reduction and sales history will update the minimum order quantity on a twice yearly basis It was critical that this project was presented as a positive for our retail store-customers. We created a communication plan that showed two key aspects of this change: ? The conservative nature of the change o only 466 of 2800 items are receiving a minimum order quantity increase ? This change is good for the stores and will improve their labor productivity To ensure that this process endures and does not get reversed over time we included a control plan. This is shown in the graphic below. As Category Marketing Managers evaluate items, adding and reducing SKUs, changes will be reflected in new pack-out quantities. This quantity will get fed to Distribution Technology who will recalculate this items’ minimum order quantity using the same Multi-Variable Pareto calculation. A control group, made up of Merchandising, Distribution and Retail Directors will review the list, make changes in the ordering system and communicate changes to store customers. info@supplyvelocity. com Copyright: Supply Velocity, Inc. 10 Results By taking the higher sales volume SKUs and increasing the store minimum order quantity, we decreased the time per case to stock shelves in the stores and select items in the distribution centers. Using only the 1 to 2 case increase in minimum order quantity for the 466 SKUs reduced the labor time per case resulting in a labor savings of $1. 2 million. The expectation for this process is to slowly grow the number items with a minimum order quantity greater than 1 case beyond 20%. By rationalizing and reducing SKUs we should increase the shelf pack-out of remaining items, thereby increasing the minimum order quantity.