Singapores Advancion

Singapores Advancion Introduction Singapore is a country in Asia and is known officially the Republic of Singapore. It is an island country which is at the south of Malaysia. Singapore is a small country which has a population of about 5 million people. The population mainly consists of people of Chinese origin, Indians and other Asians of diverse origins.Advertising We will write a custom research paper sample on Singapores Advancion in Economy, Tourism and Other Economy Building Sectors specifically for you for only $16.05 $11/page Learn More It is worth noting that Singapore has a busy port, one of the busiest in the world. Due to its small size, Singapore is one of the most densely populated countries in the world. Her population has a large percentage of foreigners who go there for leisure, business and other activities. Singapore is also a leading financial center in the world. Living conditions Singapore has among the best living conditions in Asia. According to the curre nt statistics, the country boasts excellent living conditions in Asia. It has also been ranked as the world’s number 1 in city infrastructure because of how the city is planned (Contact Singapore 2010) Diet and nutrition Nutrition in Singapore is complete with proteins, vitamins and starch together with other nutrients. The major source of proteins is pork and chicken meat, calcium is also included in the diet. Crabs and fish are sources of calcium. Vegetables and fruits provide major sources of vitamins in their diet. Typical meals Typical Singaporean meals are meat and vegetable recipes. They range from certain traditional foods that are sources of proteins. Most common food Most common food in Singapore is meat dish and vegetarian dishes which come in a range of recipes. Crab, Mee Siam, Opor Sotong Bak KutTeh and crisps are among the common traditional Singaporean foods. Smoked spicy chicken, cucumber and Bak Kwa are also common at home and across major hotels in Singapore . Most of the mail meals are usually accompanied with strong chillie. Vegetable dishes of Singapore include, melons and mango salads, Malnutrition Malnutrition in Singapore is greatly reduced because of implementation of important health policies by the government.Advertising Looking for research paper on geography? Let's see if we can help you! Get your first paper with 15% OFF Learn More Housing The real estate in Singapore is highly developed. The city has houses which it offers for sale or for rental purposes. Management of public housing is usually done by the housing and development board which is involved in building and maintaining public houses. Residential property in this city can generally be categorized into two, public housing and private housing whereby most of the population dwells in the more affordable public housing (Contact Singapore, 2010). Types of houses available The types of houses available are mainly apartments, bungalows, condomini ums, public housing flats, shophouse, semi-detached terrace house and townhouses. Shop Houses at Back Arab Street, Source: Travel guide Rent or own Rental properties are present all over Singapore. Own houses are also provided for by the real estate upon purchase. Single family/multiple family dwellings Most people in Singapore who have families usually live in larger houses. The houses may be mainly townhouses. The detached single family house is also common in Singapore. They are mostly found in the affluent areas of the city, in Singapore.Advertising We will write a custom research paper sample on Singapores Advancion in Economy, Tourism and Other Economy Building Sectors specifically for you for only $16.05 $11/page Learn More As a comparison houses in America are mainly the Creole cottage, American craftsman house, conch house, cracker house and many others. Multiple family dwelling units are found especially in apartments and in flats. This is becau se they save on space and money. Single family dwelling units are usually more expensive thus preferred only to the willing and able (Travel guide 2010). Clothing There are both modern and traditional clothing in Singapore. Most clothing in Singapore depends on the weather. In hot sunny weather, lighter clothing is common. However if the weather is emotionally rainy, thick clothing is preferred. Modern clothing in Singapore Source: fash-eccentric.com Recreation, sports and others Singapore has a host of sporting activities. Leisure in Singapore is also highly developed. Horse riding, cycling, bowling, g-max reverse bungy and Cinemania are some of the examples of Singaporean sports. Social security Social security for retirees in Singapore is provided by the government and the private sector. This is present as a compulsory scheme for any worker in Singapore.Advertising Looking for research paper on geography? Let's see if we can help you! Get your first paper with 15% OFF Learn More Health care system The healthcare system in this country is mainly placed under the government. The ministry of health is responsible in implementing health policies in Singapore. The country boasts a universal health care system where access to medical facilities because there are compulsory medical schemes that ensure that saving is a must for its citizens. Public health is much advanced in Singapore. Hospitals and major health centers are well equipped with world class facilities which offer services to the people around. Aesthetics Singapore has a lot of aesthetics for its citizens. When you visit the city, you will be encounter colorful buildings and scenery. Color is given priority in Singapore. Most street buildings are given a colorful finish such that there is pomp of color along one particular street Visual arts Currently there are more than 300 companies that offer the services of visual arts. This industry has been growing day by day such that since time immemorial, Euro pean painters and local talented people showcased their talents in Singapore. There are many people who are well known all over Singapore for being involved in the development of this industry. Some of them are, Chen Chong Swee and Georgette Chen who were teachers at some of the schools involved in this industry. The artists of Singapore are also well known worldwide. The industry of visual arts in Singapore has also made major global contributions (Flickr, 2010). Music Singaporean styles of music range from jazz, rock Indie music across to patriotic songs. Singapore has many religions which include Chinese and Indian religions. Singapore is tolerant with other types of music and cultures from all over the world (Teo et al, 2008). Musicians in Singapore have been involved with other artists to emerge at the top of the global scene. This is attributed to the mixture of cultures all over the country. Performing arts The presence of performing arts in Singapore and her neighbors is wel l known beyond her continental borders. Performing arts is much advanced in this country. It is mainly used as a leisure activity in entertainment and recreation (Flickr, 2010). Photo of performing arts in Singapore Source: flickr, Shotorphotography, (2010) Folklore In Singapore, folklore dates back from the years preceding its independence period. The period of colonial Singapore is characterized by the building of some parts of its city center. Since the end of the Second World War, Singapore has been experiencing a glorious growth from strength to strength. Singapore gained independence from Great Britain. Conclusion Singapore as this study reports is much advanced in economy, tourism and other economy building sectors. It is also a popular place for international visitors who go there for tour or investment. Therefore, life in this city is much favorable for many different cultures. Reference List Contact Singapore (2010). Living conditions. Web. ExpatSingapore (2010). Housing in Singapore. Web. (2010). Clothing in Singapore. Web. Flickr, Shotorphotography (2010). Performing Arts in Singapore. Web. Teo , T, Hargreaves, D Lee, J, (2008). Musical Preference, Identification, and Familiarity: A Multicultural Comparison of Secondary Students from Singapore and the United Kingdom. Journal of research in music and education, vol. 56, no. 1-18-32.

Tips on Identifying two common magnolias

Tips on Identifying two common magnolias The magnolia tree is a large genus of about 220 flowering plant species worldwide. Nine species are native to the United States and Canada and  the  tree commonly refers to trees of the genus Magnolia  that are a part of  the magnolia family  Magnoliaceae.  It is interesting to note that the tulip tree or yellow poplar is in the same family but in a  different genus called Liriodendron and I deal with it separately. ID Tips: The major identification markers of North American  magnolia during the spring/early summer growing season are big aromatic flowers with many parts including showy petals and sepals. Their leaves are alternate  in arrangement but can appear whorled at the branch tips. They tend to be large and often floppy with rolling to waving  edges The fruit of the magnolia is also a great way to identify the tree as it is relatively large and unique in shape.  Magnolias have large  seed pods that look like cones, which are unique when compared to most hardwood tree species. Depending on the species, the upright  cone will expand exposing  red berries which are a favorite food for wildlife.   Cucumber Tree Vs. Southern Magnolia The Southern magnolia is defined by its name - this magnolia lives in the deep part of the southeastern United States. Arthur Plotnik in his Urban Tree Book describes it as the anointed one and a pompous evergreen tree that perfumes the southern United States in early summer and planted in warm climates all over the world. It is the Louisiana state flower and Mississippis state tree. The cucumber tree and saucer magnolia are magnolias enjoyed by the northern states and Canada. The stately cucumber tree is the only magnolia that reaches Canada and is common in the Georgia Blue Ridge Mountains. Leaves: alternate, simple, persistent or deciduous, unlobedTwigs: aromatic,  bundle scars  conspicuous.Fruit: a conelike aggregate of seed.    The Common North American Magnolias Cucumber tree Southern magnolia    The Most Common North American Hardwood List ash  - Genus  Fraxinus  beech  - Genus  Fagus  basswood  - Genus Tilia  birch  - Genus  Betula  black cherry  Ã‚  - Genus  Prunus  black walnut/butternut  - Genus  Juglans  cottonwood  Ã‚  - Genus  Populus  elm  Ã‚  - Genus   Ulmus  hackberry  Ã‚  - Genus  Ã‚  Celtis  hickory  Ã‚  - Genus  Ã‚  Carya  holly  Ã‚  - Genus  Ã‚  IIex  locust  - Genus  Robinia  and  Gleditsia  magnolia  Ã‚  - Genus  Ã‚  Magnolia  maple  - Genus  Acer  oak  - Genus  Quercus  poplar  Ã‚  - Genus  Populus  red alder  Ã‚  - Genus  Ã‚  Alnus  royal paulownia  Ã‚  - Genus  Paulownia  sassafras  Ã‚  - Genus  Ã‚  Sassafras  sweetgum  - Genus  Liquidambar  sycamore  Ã‚  - Genus  Ã‚  Platanus  tupelo  Ã‚  - Genus  Ã‚  Nyssa  willow  Ã‚  - Genus  Ã‚  Salix  yellow-poplar  - Genus  Liriodendron

Leadership Essay Example | Topics and Well Written Essays - 250 words - 70

Leadership - Essay Example I have also observed that good leaders are role models who are willing to create more leaders (Chand, 2008). They pass their leadership skills and experience to specific individuals. Leaders must accommodate innovation and be flexible to diverse opinions from other leaders and their followers. They manifest relevance by being flexible and accommodative. Indeed, good leaders seek to make a difference and engage in consultations aimed at making the best decisions. As such, leaders must be followers of experienced leaders. I observed that leaders establish strong associations and collaborations with others to enhance their skills and competence. This enables them to derive authority and respect from their followers. Most importantly, I observed that good leaders are objective and focus on growth in their organization (Chand, 2008). As such, they engage in activities like seminars and conferences that foster personal and leadership development. Nevertheless, it is evident that certain traits like corruption and misuse of power hinder good leadership. As such, it is challenging to find a good leader.Bottom of

The Leader's New Work Assignment Example | Topics and Well Written Essays - 750 words

The Leader's New Work - Assignment Example Hence, the theories serve as guideline for the organizations and their managerial and marketing staff for their survival and growth in an era of perfect competition. Contemporary business culture has witnessed a tremendous alteration in its nature and scope. Fast increase in business activities at global scale, and emergence of world as a global entity has eliminated the concept of staying isolated from the outer world. People now embark upon business venture and produce goods and services keeping in view the features of the global market. It has also multiplied the responsibilities of corporate tycoons and leaders of multinational organizations, which have to render extra services in order to make their ventures a success. Argyris (2000) has elucidated salient features and responsibilities of the corporate sector during 21st century onward, where he lays stress upon fast and perfect flow of communication in order to obtain complete information of the market scenario (77). He is of the opinion that in olden days, only the owners/directors and managers used to be responsible for the growth and progress of their organization; however, time has tak en drastic turn, because of the new era challenges, and employees and workers maintain equal responsibility for the financial uplift of their work place. Business leaders apply communication tools in order to bring change in strategic schemes. Applying of focus groups, organizational surveys and other communication tools turn out to be helpful in making assessment of the work efficiency of employees, though they do not present an in-depth analysis of the problems they undergo while performing their professional obligations (78-9). He suggests the tools including effective learning, broader empowerment and employees’ surveys as effective methods of assessing the efficiency and performance of the

Breastfeeding vs Formla Feeding Essay Example for Free

Breastfeeding vs Formla Feeding Essay Parents-to-be have a lot of things on their plate. One of those many things that parents should worry about is what their child is going to consume. The choice to either breastfeed or formula feed should be the main thing on an expectant mother’s mind far before the baby is born. The nutrition a baby takes in from milk for the first year of life is very valuable for a baby’s growth and health. The choice of breastfeeding or formula feeding should be looked at and thought about deeply before deciding a nutritional plan that will alter a child’s life forever. Furthermore, these choices will also affect the parent’s life. The main aspiration for this essay is to contrast the health benefits, cost, and convenience of breastfeeding as opposed to formula feeding. The first important difference between breast and formula feeding is the health benefits. Every time a healthy woman breastfeeds her baby, she is passing on natural antibodies and vitamins that has been known to keep the baby healthy and strengthen the newborn’s immune system. The immune system assists in fighting most infections and diseases that new babies may be susceptible to, such as ear infections, respiratory infections, diarrhea, and the common cold. Some of the illnesses are more serious and could cause sudden infant death syndrome, mainly whooping cough, meningitis, leukemia and other devastating cancers. Breastfeeding can help in the prevention and reduction of risk in developing diabetes, asthma, and allergies later in life. Formula milk, however, lacks all the natural antibodies that newborns need to strengthen an infant’s non-existent immune system to help fight off infection and illnesses. Formula milk is primarily a source of nutrition and does not contribute to the development of a newborn’s immune system. Shelby Medico 05/28/12 The second difference between breastfeeding and formula feeding is the cost. Breastfeeding is a smart choice because not only is it free, but it saves money. Instead of wasting money on manufactured milk, mothers can take advantage of the free milk produced by Mother Nature. Parents can use money saved by breastfeeding and use it toward other important items newborns need. On the other hand, formula is very expensive and the price of formula adds up. As a baby grows, the parents will have to keep up with the baby’s expanding appetite; therefore, parents will eventually find themselves spending double the amount of money on formula. Formula fed babies also will not be receiving the proper antibodies to help prevent the illnesses that lead to trips to the doctor’s office. Doctor appointments are expensive, not to mention the time off work a parent may have to take to care for a sick child. The final difference between breastfeeding and formula feeding is convenience. Convenience is the key to make feeding a baby an easier task for the parents. Breastfeeding is very convenient because it is always available day and night whenever the baby is hungry. When a mother plans to run errands or simply to go out to eat for lunch with her baby, she will not have to pack anything for the baby to eat. Another convenience of breastfeeding is that it is not necessary to prepare milk and warm bottles in the middle of the night for the half-asleep midnight feedings. Parents of formula fed babies, however, have to spend extra time boiling water to prepare the formula and sterilizing the bottles before the baby can eat. Parents also have to be cautious about warming bottles to make sure the formula milk is not too hot for the baby’s sensitive mouth. Extra inconvenient tasks that have to be done before feeding a hungry, impatient baby can be very frustrating. In conclusion, considering the health benefits, cost, and convenience of breastfeeding, it would be the most logical choice to better a new family’s life.

Perception is Reality in Virginia Woolfs Mrs. Dalloway Essay -- Woolf

Although the entire novel tells of only one day, Virginia Woolf covers a lifetime in her enlightening novel of the mystery of the human personality. The delicate Clarissa Dalloway, a disciplined English lady, provides the perfect contrast to Septimus Warren Smith, an insane ex-soldier living in chaos. Even though the two never meet, these two correspond in that they strive to maintain possession of themselves, of their souls. On this Wednesday in June of 1923, as Clarissa prepares for her party that night, events during the day trigger memories and recollections of her past, and Woolf offers these bits to the reader, who must then form the psychological and emotional make-up of Mrs. Dalloway in his/her own mind. The reader also learns of Clarissa Dalloway through the thoughts of other characters, such as her old passion Peter Walsh, her husband Richard, and her daughter Elizabeth. Septimus Warren Smith, driven insane by witnessing the death of his friend in the war, acts as Clarissa' s societal antithesis; however, the reader learns that they often are more similar than different. Thus, Virginia Woolf examines the human personality in two distinct methods: she observes that different aspects of one's personality emerge in front of different people; also, she analyzes how the appearance of a person and the reality of that person diverge. By offering the personality in all its varying forms, Woolf demonstrates the compound nature of humans. As an extremely unconventional novel, Mrs. Dalloway poses a challenge for many avid readers; Woolf doesn't separate her novel into chapters, almost all the "action" occurs in the thoughts of characters, and, the reader must piece together the story from random bits and pieces of information... ... more. All of these contrasts affirm Woolf's contention: no one can or should ever be denoted as someone with only dominant characteristic, because no one remains unvarying. Yet this novel isn't just about Mrs. Dalloway or her complex nature, but rather of Woolf's realization that as Mrs. Dalloway is multi-dimensional, every human is a mixture of his/her concepts, memories, emotions; still, that same human being leaves behind as many different impressions as there are people who associate with that person. Furthermore, Woolf evokes the following question: If everyone's impression of another is just a fragment of the whole, what is the "real world" like, where everyone's consummate nature is in view? Only then does one realize that such a thing, a consummate nature, doesn't exist, and with the human personality, what you see at this very instant is what you get. Â  

Adult Development Analysis

Lamis came from a family that originated from the country of Pakistan. She has a big family–her mother, father, fiver brothers, and two sisters–and they all give importance to the values, culture and behaviors inculcated into their minds by their parents. She expressed how blessed she was to be in a family that treasures love, respect, integrity, and life.Lamis life was indeed very challenging because she grew up amidst various complexities in life. When she was a little child, she was always confused as to whose directions should she follow because she has parents who are entirely two different individuals. Her mother is someone who loves to be with people so much.She likes socializing with people and undertaking activities with them because such experience gives her certain pleasure and enjoyment that she does not find in any other places. Her father, on the other hand, is the exact opposite of her mother. He does not like the idea of being with people.He is more comf ortable being alone in his own place, perhaps because her father is a very private person. He keeps a lot of things in his mind and usually do not share most of those things to her mother. Furthermore, her father is very pragmatic and he is open-minded that he understands the contemporary things they do in their lives even if those are sometimes against his beliefs.On the contrary, her mother does not want them to do things on their own. She is very strict in terms of the things they undertake. She wants them to always obey her because she believes that she knows what is best for her children.The contradictions demonstrated by Lamis’ parents made her initially a very confused individual. It affected the development of her morality. She told me she loves both of her parents so she was usually torn between whether to follow her father or her mother.She eventually learned to balance the characters of her parents and somehow managed to grasp the positivity of their differing indi vidualities and created a whole set of values, behaviors, and beliefs that influenced her moral development.Lawrence Kohlberg, a theorist who proposed the concept of moral development, conceived that individuals continue through each stage of moral development consecutively without skipping or returning to a previous stage.According to him, the stages of processing ideas, implying qualitatively, various ways of reasoning, and of problem solving are incorporated in the three levels of pre-conventional, conventional and post conventional development (Hayes, 1994).The pre-conventional level of Kohlberg’s moral development theory communicated that behavior is motivated by anticipation of pleasure or pain (Hayes, 1994). The child is aware of cultural rules and labels of good or bad and right or wrong.The subject then interprets the labels in terms of the physical consequence, such as punishment or reward. This was true in Lamis’ family particularly with how her parents rais ed them. Her mother, in particular, would always want them to help each other and to do things in accordance with her will because she was so strict during those times. She would not allow them to play outside the house if any of them disobey her.Also, she wanted them to always study hard and incessantly reminded them the importance of education in their life. Hence, she would keep their toys and other sources of entertainment like television if they do not review their lessons at least two hours everyday.Her father, on the other hand, would reward them for every good things they do like cleaning the house, fixing their bedrooms, and studying their lessons. He would buy them special cookies or their favorite chocolates every good grade they get from school.Going back to Kohlberg’s moral development theory, the first level, pre-conventional, of moral thinking is generally found at the elementary school level, before the age of nine (Kay, 1982). This level is divided into the f ollowing two stages.The punishment and obedience orientation. This is observed in children ages one to five. The subject is in avoidance of physical punishment and deference to power. The child behaves according to the socially acceptable norms, due to the fear of punishment by an authority figure. The physical aftermaths of an action ascertain its goodness or badness.â€Å"What is right is to avoid breaking rules, to obey for obedience’s sake, and to avoid doing physical damage to people and property† (as cited in Wart, 1998, p. 36). Furthermore, an individual at this stage does not consider the thoughts or feelings of others, nor are they able to relate two points of view. As in Piaget’s framework, ego-centrism and the inability to consider the perspectives of others characterize the reasoning of stage one (Piaget, 2003).The individual instrumental purpose and exchange orientation. Subjects usually between the ages of 5 to 10 are observed maintaining the attri butes of being â€Å"self-serving.† This stage is â€Å"characterized by a view that right behavior means acting in one’s own best interest and occasionally taking into consideration the needs of others† (Penn State Engineering, 2006).There is an early emergence of moral reciprocity. â€Å"You scratch my back, I’ll scratch yours.† The individual will do what is necessary to satisfy his own needs not concentrating on loyalty or gratitude. Justice becomes â€Å"Do unto others as they do unto you.† What is right is the immediate interest in the form of an equal exchange, deal or agreement.A subject at this stage of moral development has a basic understanding that norms and conventions are necessary to uphold society. The motto of this stage is â€Å"What’s in it for me?† Elements of sharing are present but are interpreted in a physical pragmatic way (Hayes, 1994).When Lamis was a little kid, she told me she really did not care so much about the feelings of other people like her siblings and playmates. What was important for her was to play and made sure that she did not violate any of her parents’ rules because her strict mother would surely punish her.Lamis was so young then that she actually did not understand everything her mother told her but she did acknowledge the fact that her mother would not be happy if she does something wrong. Until Lamis learned to care about other people and realize the importance of doing good things to others.Her father played an important part in making her understand the essentiality of recognizing the welfare of other individuals in order for those people to do the same good things to her.Lamis’ early learning experiences were fundamentally influenced by her family. She told me during the interview that she did not go to school early, unlike other children, because she had asthma. She only started to go to school when she was eight years old.Apart from the fac t that she had asthma, her parents were scared to leave Lamis in school at a very early age. Such action, according to her, was perhaps due to the conservatism in their culture. Yet, her father never forgot to tell her good things about going to school and learning new things from a teacher.Lamis’ father would always narrate his positive experiences he acquired from school and things that education allowed him to do. Hence, Lamis became really interested in going to school and in fact, became one of the best students when she started her formal education.Furthermore, Lamis was very thankful to her mother being extrovert. Although she was not allowed to go to school at an early age, her mother would always bring her whenever her mother would socialize with her friends and this was perhaps where she learned most of her social skills, where, according to Kohlberg and Piaget, most moral development occurs along with aging process (Duska & Whelan, 1975).When Lamis started her firs t formal education in Saudi Arabia, she admitted to me that she had complicated experiences the first time basically because she found it very challenging to assimilate to the culture of her school considering that her native culture was very different from the school culture in so many ways.On top of this, she did not know the English language that made it more difficult for her to interact with and understand her classmates. She shared to me one experience and this happened during the school opening. She came to school with short hair and most of her classmates were making fun of her.Since she did not understand the language, she did not get affected and instead maintained her good values and behaviors that her parents inculcated into her mind. Lamis further shared to me some of her strengths when she was a student. She told me she was that kind of student who leads and influences other students. She never got intimidated by the presence of her classmates.In fact, she was the clas s leader and she was the one assigned to do the morning news and introduction at school. She was capable of handling the entire class and her teacher actually entrusted to her the class whenever the teacher leaves. She took responsibilities very well. Such behaviors gave her good grades in school for 12 years.During this part of the interview, I was able to trace where these positive and strong attitudes and behaviors came from. I believe her being strong, socially interactive, intelligent, independent, and creative was due to the trainings provided by her parents when she was a little kid.As mentioned earlier, Lamis was introduced to the notion of reward and punishment system when she was young. Her strict mother would always ask her to study and do things accordingly; otherwise a corresponding punishment would be executed.The interview moreover reveals that Lamis’ life is heavily influenced by her many personal encounters with an array of people of equally diverging persona lity types. Which is why, Erik Erikson’s psychosocial theory appears to be a very good choice to help further elucidate Lamis’ unique learning tendencies and personality traits.Erikson’s model, if only to mention, puts higher premium than most on exploring the environmental influences of a person as one grows up. In other words, it â€Å"considers the impact of external factors, parents and society on personality development from childhood to adulthood† (Learning Theories, 2007).According to Erik Erikson, each person needs to undergo eight major life-defining stages over the period of their given life spans. And these stages, on a careful analysis, have two chief characteristics. First, these interrelated life stages – infancy, toddler-hood, school-age, adolescence, early and mid and late-adulthood – are differentiated not by the traditional approach involving the use of chronologically-based age ordering system.Put in other words, Eriksonâ €™s model does not rely on the age of the person in solely evaluating his or her psychological development. Instead, Erikson conceives of these life stages always view of the growth and development of a person achieves relative to his or her age. Critical to his notion of psychosocial theory of personality development is the areas of growth that come with each life stage.Second, every life stage consists in â€Å"a developmental task that confronts individuals with crisis† (Satrock, 2006, p. 71). Erikson’s model maintains that a person needs to find a resourceful way to successfully hurdle the respective crises each life stage brings him or her. If a person resolves a crisis, it serves his growth process well.If a person is unable figure a resolution for it, chances are, it stalls the development of his or her growth and well being. Crises, in needs to argued, are life-defining moments. And as such, it promises not only an ugly catastrophe for a person, but an â₠¬Å"enhanced potential† of a healthy psychological life as well (p. 71).During infancy, Erikson believes that a person needs to resolve fundamental trusts issues. This is achieved when a child is adequately nurtured; i.e., if the immediate environment – the mother, father and siblings, among others – responds well to his or her needs.If a child did not establish a basic sense of security from the family, it can result to an unfortunate retardation of his capacity to trust the larger world later on. Stage two meanwhile pertains to the struggle of a toddler to establish his will.During this stage, a child is able to learn many new things and is beginning to learn what is right from wrong. Depending on the way a person is nurtured at this particular stage, a child can either end up having a strong sense of autonomy or shame.The next phase is the preschooler stage – a time, as it were, to indulge in childhood curiosity. When properly affirmed, a child can devel op a good sense of initiative. When constantly rebuked, a child is expected to develop a gripping sense of guilt.According to Erikson, the immediate family of a child plays a very crucial role in the development or the retardation of children undergoing these three initial stages. In many ways, the importance Erikson places on the role of the family makes his theory wholly distinct from the more inclination-indulging theory of S. Freud (Erikson, 1964, p. 9)Stage four meanwhile concerns the school phase of a child. During these years, a child needs to be empowered to develop his or her competence and self-esteem. At this stage too, a child can either develop a sense of industry or inferiority depending on the manner by which he or she successfully handles the pressures of peer and studies.The next phase is the adolescence stage. At this point, the influence of the family, especially the parents, start to diminish. Everyone’s chief concern at this stage is to establish fidelity in one’s personal affiliation, belongingness, or even relationships. Moreover, a person can either end up establishing a strong sense of who he or she is, or wound up under-developing his or her identity in a crisis marked by severe confusion. Stages six to eight pertains to a person in his or her adulthood.In particular, stage six, or the early adulthood stage, underscores a person’s struggle for love. Since this is the stage proper to establishing relationships, a person can either nurture intimacy or fall apart because of isolation. Stages seven and eight are phases that involve a person’s quest for generativity and integrity. When undermined, a person can sorely wound up into a stage of extreme wallowing and despair (Learning Theories, 2007; Satrock, 2006, pp 71-72).Using Erik Erikson’s theory to evaluate Lamis, the following observations can be noted:First, it can be said that Lamis’ authoritative comportment and unmistakable confidence take root from a successful resolution of her life’s first stage. Lamis’s early life was marked by healthy interaction with her family members.And because each person takes on the â€Å"capital† of gaining something from one’s family of origin (Wartofsky, 1986, p. 113), it can be argued that Lamis’ was able to gain the all important aspect of familial love in her life. Lamis admits belonging to a family that places much regard on care, love and nurturance.Moreover, her being born into a large family turned out to be an advantage for her as well, since her basic need to be nurtured and taken care of as an infant was addressed. This is perhaps the most fundamental reason why Lamis was to develop a strong sense of security as an adult; as indeed, this factor too may help explain why she looks at the world brimming with confidence, optimism and pride.Next, one can also note that Lamis’ is herself quite clued-up with the fact that most of what she bel ieves in and holds on in life stem from the unique manner by which she was nurtured. For instance, Lamis claims that early on in life, she already manifested a certain strain of stoicism towards feelings on account of a very strong sense of rules and punishment-reinforcements.For someone who was just beginning to explore the world, it seems pretty obvious that Lamis developed a sense of autonomy defined by how successful she was able to play by the rules. Her desire to avoid being punished and suffer the shame of being reprimanded by her otherwise rigorous mother was controlling motive for this.As such, this is a classic case of autonomy vs. shame struggle manifested by toddlers. In the process, what emerged from her struggle to obey was a person who has a specific leaning towards obedience and a knack on leadership that influences other people to obey as well.Lastly, it has to be mentioned as well that Lamis’ school age is also marked by a successful overcoming of inferiorit y and low self esteem crises. During the interview, Lamis revealed that her initial contact with the school environment turned out rather unpleasant; as indeed, she had to adjust into the school system rather quickly (since she did not have any schooling prior to her entrance at the age of eight), and put up with incessant teasing of her classmates.But because she was nurtured by a family that cared and supported her, she was able to overcome her school-age crises. In the process, she developed her sense of initiative and industry. This is perhaps seen most glaringly in the healthy and motivated way by which she views her efforts to succeed well in her studies even until the present.To briefly conclude, this paper ends with a thought that, indeed, Erik Erikson’s psychosocial theory is able to provide a window for us to look at Lamis’ belief system, behavioral uniqueness and personal worldviews within the larger context of her past experiences. Lamis is indeed a person shaped by the interactions she has had in her lifetime.It is imperative to note that in the years to come, she is to encounter more life defining crises; this time about issues pertinent to adulthood. But what stands out for the meantime is her triumphant emergence from the three identified crises she has thus far encountered.After using Erikson’s theory, we were able to affirm that Lamis’ being able to establish a healthy sense of confidence as an infant, autonomy as toddler, and initiative and industry as a school-age child, surely did serve her well.BibliographyDuska, R. & Whelan, M. (1975). Moral development: A guide to Piaget and Kohlberg. New Jersey: Paulist Press.Erikson, E. (1964). Insight and Responsibility. Lectures on the Ethical Implications of   Ã‚   Psychoanalytic Insight. New York: Norton and Company.Hayes, R. L. (1994). The legacy of Lawrence Kohlberg: Implications for counseling and human development. Journal of Counseling & Development, 72(3), pp. 2 61-267.Kay, S. R. (1982). Kohlberg’s theory of moral development: Critical analysis of validation studies with the defining issues test. International Journal of Psychology, 17(1), pp. 27-43.Learning Theories Knowledgebase (2008). â€Å"Erikson’s Stages of Development†. Retrieved 28   Ã‚  Ã‚  Ã‚   July 2008, from Penn State Engineering. (2006). Ethical decision making processes. Retrieved June 24, 2008, from http://www.vanderbilt.edu/CenterforEthics/Descriptions-More%20Info/Resource%20Pages%20for%20Ethics%20Workshop%20-%202006.pdf.Piaget, J. (2003). Part I: Cognitive development in children – Piaget development and learning. Journal of Research in Science Teaching, 40(1), pp. 8-18.Satrock, J. (2006). Educational Psychology. New York, McGraw Hill, Inc.Wart, M. V. (1998). Changing public sector values: Montgomery Van Wart. Taylor & Francis.

Demand Forecasting and Production Planning

ScienceAsia 27 (2001) : 271-278 Demand Forecasting and Production Planning for Highly Seasonal Demand Situations: Case Study of a Pressure Container Factory Pisal Yenradeea,*, Anulark Pinnoib and Amnaj Charoenthavornyingb a Industrial Engineering Program, Sirindhorn International Institute of Technology, Thammasat University, Patumtani 12121, Thailand. b Industrial Systems Engineering Program, School of Advanced Technologies, Asian Institute of Technology, P. O. Box 4, Klong Luang, Patumtani 12120, Thailand. * Corresponding author, E-mail: [email  protected] tu. ac. th Received 24 May 2001 Accepted 27 Jul 2001 ABSTRACT This paper addresses demand forecasting and production planning for a pressure container factory in Thailand, where the demand patterns of individual product groups are highly seasonal. Three forecasting models, namely, Winter’s, decomposition, and Auto-Regressive Integrated Moving Average (ARIMA), are applied to forecast the product demands. The results are compared with those obtained by subjective and intuitive judgements (which is the current practice). It is found that the decomposition and ARIMA models provide lower forecast errors in all product groups. As a result, the safety stock calculated based on the errors of these two models is considerably less than that of the current practice. The forecasted demand and safety stock are subsequently used as inputs to determine the production plan that minimizes the total overtime and inventory holding costs based on a fixed workforce level and an available overtime. The production planning problem is formulated as a linear programming model whose decision variables include production quantities, inventory levels, and overtime requirements. The results reveal that the total costs could be reduced by 13. % when appropriate forecasting models are applied in place of the current practice. KEYWORDS: demand forecasting, highly seasonal demand, ARIMA method, production planning, linear programming, pressure container factory. INTRODUCTION Most manufacturing companies in developing countries determine product demand forecasts and production plans using subjective and intuitive judgments. This may be one factor that leads to production inefficiency. An accuracy of the demand forecast significantly affects safety stock and inventory levels, inventory holding costs, and customer service levels. When the demand is highly seasonal, it is unlikely that an accurate forecast can be obtained without the use of an appropriate forecasting model. The demand forecast is one among several critical inputs of a production planning process. When the forecast is inaccurate, the obtained production plan will be unreliable, and may result in over- or understock problems. To avoid them, a suitable amount of safety stock must be provided, which requires additional investment in inventory and results in an increased inventory holding costs. In order to solve the above-mentioned problems, systematic demand forecasting and production planning methods are proposed in this paper. A case study of a pressure container factory in Thailand is presented to demonstrate how the methods can be developed and implemented. This study illustrates that an improvement of demand forecasts and a reduction of total production costs can be achieved when the systematic demand forecasting and production planning methods are applied. The demand forecasting and production planning methods are proposed in the next section. The background of the case study, including, products, production process, and the forecasting and production planning procedures being used in the factory, are briefly described in Section 3. The detailed analyses of the forecasting methods and the production planning method are explained in Section 4 and Section 5, respectively. Finally, the discussion and conclusion are presented in Section 6. 272 ScienceAsia 27 (2001) P ROPOSED D EMAND F ORECASTING PRODUCTION PLANNING METHODS AND The proposed demand forecasting and production planning methods are depicted in a step-by-step fashion in Fig. . Most factories produce a variety of products that can be categorized into product groups or families. Individual products in the same product group generally have some common characteristics. For example, they may have the same demand pattern and a relatively stable product mix. As a result, it is possible to forecast the aggregate demand of the product group first, and then disaggregate it in to the demand of individual products. Since the forecast of the aggregate demand is more accurate than that of the individual demand1, it is initially determined in Step 1. Then the demands of individual products are determined in Step 2 by multiplying the aggregate demand with the corresponding product mix that is normally known and quite constant. Since the demand forecasts are always subject to forecast errors, safety stocks are provided to avoid stock-out problems. Based on the standard deviation of the forecast errors and the required service level, the safety stocks for individual products are determined in Step 3. Production planning decisions are so complicated and important that they should not be subjectively and intuitively made. Consequently, an appropriate production planning model should be formulated to determine the optimal decisions. With this model, its parameters, eg, demand forecasts, safety stocks, holding cost, overtime cost, machine capacity, inventory capacity, and available regular time and overtime, are entered or updated (Step 4). In step 5, the optimal decisions regarding the production quantities, inventory levels, and regular production time and overtime for each product in each production stage are obtained by solving the production planning model. Step 6 indicates that only the optimal production plan of the current month will be implemented. After one month has elapsed, the demand forecasts and the production plan will be revised (by repeating Steps 1 to 5) according to a rolling horizon concept. BACKGROUND OF THE CASE STUDY The pressure container factory manufactures 15 products, ranging from 1. 25 to 50 kg of the capacity of pressurized gas. The products are divided into eight product groups, namely, Group 1 to Group 8. The first six groups have only two components, â€Å"head† and â€Å"bottom†, while the last two groups have three components, â€Å"head†, â€Å"bottom†, and â€Å"body†. The production process can be divided into five stages as shown in Fig. 2. Stage 3 is only required to produce the products having three components (ie, those in Groups 7 and 8). Stage 4, the circumference welding, is found to be a bottleneck stage due to its long processing time. Presently monthly demand forecasts are subjectively determined by the Marketing Department based on past sales and expected future market conditions. No systematic method is used in forecasting. Using these forecasts and other constraints, such as availability of raw materials, equipment, and production capacity, the monthly production plan for a three-month period is intuitively determined without considering any cost factor. This results in inaccurate demand forecasts and, subsequently, an inefficient production plan. Stage 1 Blanking 1) Forecast the monthly demands of each product group throughout the planning horizon of 12 months 2) Determine the demand for each individual product 3) Determine the safety stock for each individual product Stage 2 Forming of bottom and head Stage 3 Forming of body 4) Update the parameters in the production planning model Stage 4 Circumference welding 5) Run the planning model to obtain the optimal planning dicisions ) Roll the plan by repeating Steps 1 to 5 after one month has elapsed Stage 5 Finishing Fig 1. Proposed forecasting and planning steps. Fig 2. The production process to manufacture a pressure container. ScienceAsia 27 (2001) 273 FORECASTING METHODS Steps 1, 2, and 3 of the proposed forecasting and planning process are discussed in detail in this section. Firstly, the aggregate demand forecasts of eight product groups throughout the planning horizon of 12 mont hs will be determined. Secondly, the demand forecasts of the product groups will be disaggregated into those of individual product. Thirdly, the safety stocks of individual product will be calculated based on the forecast error. Aggregate Demand Forecasts of Product Groups The typical demand pattern of each product group is seasonal. As an example, Fig. 3 shows the demand pattern of Product Group 3. Thus, three forecasting models that are suitable for making seasonal demand forecasts are considered. They are Winter’s, decomposition and Auto-Regressive Integrated Moving Average (ARIMA) models. 2-5 Because of their simplicity, the Winter’s and decomposition models are initially used to forecast the aggregate demand of each product group. If the Winter’s and decomposition models are inadequate (ie, the forecast errors are not random), the ARIMA model which is more complicated and perhaps more efficient will be applied. The Winter’s model has three smoothing parameters that significantly affect the accuracy of the forecasts. These parameters are varied at many levels using a computer program to determine a set of parameters that give the least forecast errors. There are two types of the decomposition model, namely, multiplicative and additive types. The former is selected since the demand pattern shows that the trend and seasonal components are dependent. The forecast errors of the Winter’s and decomposition models are presented in Table 1. Based on the calculated mean square error (MSE) and the mean absolute percentage error (MAPE), it is seen that the decomposition model has lower Original Series (x 1000) 16 forecast errors in all product groups than the Winter’s model. Thus, it is reasonable to conclude that the decomposition model provides better demand forecasts than the other. One way to check whether the forecasting model is adequate is to evaluate the randomness of the forecast errors. The auto-correlation coefficient functions (ACFs) of the errors from the decomposition model for several time lags at the significant level of 0. 05 of each product group are determined. The ACFs of Groups 1 and 3 are presented as examples in Fig. 4 and 5, respectively. The ACFs of Groups 4, 5, 6, 7, and 8 are similar to those of Group 1 in Table 1. Forecast errors of the Winter’s and decomposition models. MSE Products MAPE (%) Winter’s Decomposition Winter’s Decomposition 9,879,330 4,363,290 2,227,592 4,507,990 10,039,690 574,108 636,755 883,811 36. 14 48. 94 24. 25 30. 08 18. 80 53. 86 61. 99 46. 52 26. 97 31. 86 15. 97 23. 4 13. 14 34. 80 34. 45 28. 76 Group 1 16,855,149 Group 2 8,485,892 Group 3 5,433,666 Group 4 6,035,466 Group 5 23,030,657 Group 6 1,690,763 Group 7 2,034,917 Group 8 1,884,353 Estimated Autocorrelations 1 0. 5 coefficient 0 -0. 5 -1 0 4 8 lag 12 16 20 Fig 4. ACFs of the residuals from the decomposition model for Group 1. Estimated Autocorrel ations 1 0. 5 16 demand 3 coefficient 0 8 -0. 5 4 -1 0 0 10 20 30 time index 40 50 60 0 4 8 lag 12 16 20 Fig 3. Actual demand of Group 3. Fig 5. ACFs of the residuals from the decomposition model for Group 3. 274 ScienceAsia 27 (2001) Fig 4, while those of Groups 2 and 3 are similar. It can be seen from Fig. 4 that the ACFs of all lags are within the upper and lower limits, meaning that the errors are random. However, the ACF of lag 1 in Fig. 5 exceeds the upper limit. This indicates that auto-correlations do exist in the errors and that the errors are not random. From the ACFs, we can conclude that the decomposition model is adequate for forecasting the demands of Groups 1, 4, 5, 6, 7, and 8, but inadequate for forecasting those of Groups 2 and 3. Therefore, the ARIMA model is applied to Groups 2 and 3. From the original time series of the demand of Group 3 (in Fig. 3), and the ACFs of its original series (in Fig. ), it can be interpreted that the original series has a trend, and a high value of ACF of lag 12 indicates the existence of seasonality. 2 Hence, a non-seasonal first-difference to remove the trend and a seasonal first-difference to remove the strong seasonal spikes in the ACFs are tested. Fig. 7 shows the ACFs of the ARIMA (p,1,q)(P,1,Q) 12 model afte r applying the first difference. The nonseasonal plot indicates that there is an exponential decay and one significant ACF of lag 2. Thus, the AR(1) and MA(1) process denoted by ARIMA (1,1,1)(0,1,0)12 is identified. The ACFs of the residuals after applying this ARIMA model shown in Fig. reveals that there is a high value of ACF of lag 12. Therefore, the AR(1) and MA(1) process for the seasonal part or ARIMA (1,1,1)(1,1,1)12 can be identified. The ACFs of the residuals generated from this model are shown in Fig. 9. Since all ACFs are within the two significant limits, the ARIMA (1,1,1)(1,1,1)12 model is adequate. Using the Statgraphic program, the model coefficients can be determined. The demand forecast for Group 3 is presented in Eq. 1. Ft = 1. 197 X t ? 1 ? 0. 197 X t ? 2 + 0. 54408 X t ? 12 ? 0. 65126 X t ? 13 + 0. 10718 X t ? 14 + 0. 45592 X t ? 24 ? 0. 54574 X t ? 25 + 0. 08982 X t ? 26 ? 1. 6699et ? 1 ? 0. 7154et ? 12 + 0. 76332et ? 13 + 29. 34781 (1) where Ft is the demand fo recast for period t Xt is the actual demand for period t et is the forecast error for period t Similarly, the forecasting model for Group 2 is ARIMA (3,0,0)(3,0,0). 12 The demand forecast of Group 2 is presented in Eq. 2. Estimated Autocorrelations for Original Series 1 Estimated Residual ACF 1 0. 5 0. 5 coefficient coefficient 0 0 -0. 5 -0. 5 -1 0 5 10 lag 15 20 25 -1 0 5 10 lag 15 20 25 Fig 6. ACFs of the actual demand for Group 3. Fig 8. ACFs of the residuals of ARIMA (1,1,1)(0,1,0)12 model for Group 3. Estimated Residual ACF 1 Estimated Autocorrelations for 1 Nonseasonal Differences 1 Seasonal Differences 1 0. 5 0. 5 coefficient coefficient 0 0 -0. 5 -0. 5 -1 0 5 10 lag 15 20 25 -1 0 5 10 lag 15 20 25 Fig 7. ACFs after first differencing for Group 3. Fig 9. ACFs of the residuals of ARIMA (1,1,1)(1,1,1)12 model for Group 3. ScienceAsia 27 (2001) 275 Ft = 0. 36951X t? 1 + 0. 30695X t? 2 – 0. 18213X t? 3 + 0. 20132 X t? 12 ? 0. 07439 X t? 13 ? 0. 06180 X 14 + 0. 03667 X t? 15 ? 0. 03325X t? 24 + 0. 01228 X t? 25 + 0. 01021X t? 26 ? 0. 00606 X t? 27 + 0. 68660 X t? 36 ? 0. 25371X t? 37 ? 0. 21075X t? 38 + 0. 12505X t? 39 + 354. 4515 2) The forecast errors of the decomposition and ARIMA models for Groups 2 and 3 are presented in Table 2. It reveals that the ARIMA model has lower Table 2. Forecast errors of the decomposition and ARIMA models. MSE Products Group 2 Group 3 Decomposition ARIMA 4,363,290 2,227,592 3,112,974 1,235,788 MAPE (%) Decomposition ARIMA 31. 86 15. 97 29. 05 13. 18 MSE and MAPE than t he decomposition model. Therefore, the ARIMA model should be used to forecast the aggregate demands of Groups 2 and 3. For other product groups, however, the decomposition model should be used because it is more simple yet still adequate. The comparison of the demand forecast errors obtained from the forecasting models and those from the current practice of the marketing department (as presented in Table 3) indicates that the errors of the forecasting models are substantially lower than those of the current practice. Demand Forecasts of Individual Products The demand forecast of product i for period t, dit, is obtained by multiplying the aggregate demand forecast of the product group (obtained from the previous steps) by the corresponding product mix (as presented in Table 4). Table 3. Forecast errors of the current practice, decomposition, and ARIMA models. MSE Product Group 1 Group 2 Group 3 Group 4 Group 5 Group 6 Group 7 Group 8 Current practice Decomposition 16,672,342 4,394,693 4,988,962 4,754,572 19,787,102 795,621 849,420 1,060,301 9,879,330 4,507,990 10,039,690 574,108 636,755 883,811 ARIMA 3,112,974 1,235,788 MAPE (%) Current practice Decomposition 30. 58 34. 68 23. 50 25. 73 17. 54 42. 70 38. 36 37. 93 26. 97 23. 24 13. 14 34. 80 34. 45 28. 76 ARIMA 29. 05 13. 18 – Table 4. Product mix. Product group Product 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 1 0. 17 0. 20 0. 26 0. 23 0. 14 1. 0 0. 53 0. 47 0. 65 0. 35 1. 0 1. 0 1. 0. 3 0. 7 2 3 4 5 6 7 8 276 ScienceAsia 27 (2001) Calculation of Safety Stock The safety stocks of finished products must be provided to protect against stock-out problems due to inaccurate demand forecasts. Based on the forecast errors obtained from the demand forecasting models, the amount of the safety stock is calculated using the following formula. 12 SSit = sf * ? j * ? ij (3) PRODUCTION PLANNING METHO D The production planning model is developed by initially defining decision variables and parameters, and then mathematically formulating the production planning model. Step 4 of the method requires that the model parameters be estimated and entered into the model. The model is solved for the optimal solution (Step 5). Step 6 recommends that the model parameters are updated, and the model is solved again after one planning period has passed. The production planning problem of the factory under consideration belongs to the class of multistage, multi-item, capacitated production planning model. The models in this class have been discussed extensively in. 6-11 They differ in assumptions, objectives, constraints, and solution methods. Our production planning model is a modification of the multi-stage, multi-product model discussed in Johnson and Montgomery. 6 Its objective is to minimize the total overtime and inventory holding costs. Costs of laying off and rehiring are not considered because laying off and rehiring are not allowed according to the labor union regulation. Since the production cost is time-invariant and all demands must be satisfied, the regular time production cost is thus not included in the objective function. Relevant parameters and decision variables are defined as follows: Parameters : hik = Holding cost per unit of product i at stage k (baht/unit/period) co = Cost per man-hour of overtime labor (baht/man-hour) dit = Demand forecast of product i for period t (units) aik = Processing time for one unit of product i at stage k (hours/unit) (rm)kt = Total available regular time excluding preventive maintenance and festival days at stage k for period t (man-hours) (om)kt = Total available overtime excluding preventive maintenance and festival days at stage k for period t (man-hours) W = Warehouse capacity (units) SSit = Safety stock of product i for period t (units) Iik0 = Initial inventory of product i at stage k (units) N = Total number of products (15 products) T = Total number of periods in the planning horizon (12 periods) K = Total number of stages (5 stages) where SSit = Required safety stock level of product i for period t sf = Safety factor = 1. 64 for a required service level of 95 % of the standard normal distribution ? j = Standard deviation of forecast errors of Group j. ?ij = Product mix of Product i in Group j. Since the errors of the recommended demand forecasting models are lower than those of the current practice, it is clear that SSit based on the use of the models must be lower than that determined from the current practice (assuming that the service levels of both cases are the same). Table 5 presents the required safety stocks of the current practice and the recommended forecasting models at 95 % service level. Table 5. Required safety stock of current practice and of recommended forecasting models. Safety stock (units) Product 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Current practice 1,138 1,339 1,741 1,540 937 3,438 1,941 1,722 2,324 1,252 7,295 1,463 1,511 507 1,182 Recommended forecasting models 887 1,043 1,356 1,200 730 2,905 979 868 2,274 1,224 5,258 1,245 1,323 460 1,072 ScienceAsia 27 (2001) 277 Decision variables: Xikt = Quantity of product i to be produced at stage k in period t (units) Iikt = Inventory of product i at stage k at the end of period t (units) Rkt = Regular time used at stage k during period t (man-hours) Okt = Overtime used at stage k during period t (man-hours) LP model: Minimize Z = ? ? ? hik Iikt + ? ? co Okt , (4) i =1 k =1 t =1 k =1 t =1 N K T K T Eq. 7 represents the material balance constraint in Stage 3, which produces the body of threecomponent products, for Products 13, 14, and 15. Constraint (13) must be included since the finished products are very bulky and require significant warehouse space that is quite limited. Work-inprocess inventory does not require significant storage space because it can be stacked. The non-negativity constraint (16) ensures that shortages of work-inprocess inventory do not occur. Input Parameters The initial inventory of product i at stage k, Iik0, is collected from real data of work-in-process or finished good inventories on the factory floor at the beginning of the planning horizon. The inventory holding cost of product i at stage k, hik, is estimated by assuming that the annual inventory holding cost is 25% of the cost per unit of the product at the respective production stage. Since the cost per unit is constant over the planning horizon, the annual inventory holding cost is time-invariant. The factory has enough space in the warehouse to store not more than 40,000 units of finished products. The total available regular time, (rm)kt, is estimated based on the fact that the factory is normally operated 16 hours a day and six days a week, and the total available overtime, (om)kt, is calculated by assuming that the overtime could not be more than six hours a day. The overtime cost, co, is assumed to be constant throughout the planning horizon, and is estimated to be 60 Baht per man-hour. After all related parameters have been estimated and entered into the planning model, the optimal values of all decision variables are calculated using the LINGO software. The computation time takes less than one minute on a Pentium PC. Results of the Production Planning Models with Different Levels of Safety Stock In this section, two production planning models with different safety stock levels (as shown in Table 5) are solved to determine the total cost savings when the recommended forecasting models are applied in place of the current practice. The inventory holding, overtime, and total costs of both models are presented in Table 6. Based on the optimal total cost of the current practice (4,078,746 Baht per year) and the optimal total cost of the recommended forecasting models (3,541,772 Baht per year), the total cost saving is 536,974 Baht per year, or 13. 2 %. It can be also seen Subject to – Finished product requirement constraints I i 5,t? 1 + X i 5t ? I i 5t = dit – ? i, t ; k = 5, (5) Material balance between stages constraints ? i, t ; k = 4, (6) (7) ? i, t ; k = 2, (8) ? i, t ; k = 1, (9) I i 4 ,t? 1 + X i 4 t ? I i 4 t = X i 5t I i 3,t? 1 + X i 3t ? I i 3t = X i 4 t ?t ; i = 13, 14, 15; k = 3, I i 2,t? 1 + X i 2t ? I i 2t = X i 4 t I i1,t? 1 + X i1t ? I i1t = X i 2t Capacity constraints ? aik X ikt ? Rkt + Okt i= 1 N ?k , t , (10) – Available regular and overtime constraints. Rkt ? (rm) kt Okt ? ( om) kt ?k , t , ? k , t , (11) (12) – Inventory capacity of finished product constraints. ? I ikt ? W i= 1 N ?t ; k = 5, (13) – Safety stock of finished product constraints. I ikt ? SS it ?i, t ; k = 5, (14) – Non-negativity conditions X ikt ? 0 I ikt ? 0 ?i, k , t , ? i, t ; k = 1, 2, 3, 4 (15) (16) 278 ScienceAsia 27 (2001) Table 6. Comparison of the optimal costs of production planning models. Optimal costs (Baht/year) Model based on the current practice Inventory holding cost Overtime cost Total cost 2,117,051 1,961,695 4,078,746 Model based on recommended forecasting models 1,775,552 1,766,220 3,541,772 REFERENCES 1. Nahmias S (1993) Production and Operations Analysis, 2nd ed, Irwin, New York. 2. Vandaele W (1983) Applied Time Series and Box-Jenkins Models, Academic Press, New York. 3. Winters PR (1960) Forecasting Sales by Exponentially Weighted Moving Average. Management Science 6(4), 324-42. 4. Box GE and Jenkins GM (1970) Time Series Analysis, Forecasting, and Control, Holden-Day, San Francisco. 5. Makridakis S Wheelwright SC and McGee VE (1983) Forecasting Methods and Applications, 2nd ed, John Wiley & Sons, New York. 6. Johnson LA and Montgomery DC (1974) Operations Research in Production Planning, Scheduling, and Inventory Control, John Wiley & Sons, New York. 7. Bullington P McClain J and Thomas J (1983) Mathematical Programming Approaches to Capacity Constrained MRP Systems: Review, Formulation, and Problem Reduction. Management Science 29(10). 8. Gabbay H (1979) Multi-Stage Production Planning. Management Science 25(11), 1138-48. 9. Zahorik A Thomas J and Trigeiro W (1984) Network Programming Models for Production Scheduling in MultiStage, Multi-Item Capacitated Systems. Management Science 30(3), 308-25. 10. Lanzanuer V (1970) Production and Employment Scheduling in Multi-Stage Production Systems. Naval Research Logistics Quarterly 17(2), 193-8. 11. Schwarz LB (ed) (1981) Multi-level Production and Inventory Control Systems: Theory and Practice, North-Holland, New York. 12. Tersine RJ (1994) Principles of Inventory and Materials Management, 4th ed, Prentice Hall, New Jersey. that the optimal inventory holding cost and overtime cost in the production planning model based on the recommended forecasting models are almost equal which indicates that the model can efficiently achieve a tradeoff between both costs. Normally, the optimal decisions in the first planning period will be implemented. After the first period has passed, the new forecasts will be determined, and the model parameters will be updated. The updated model is solved again to determine the optimal decisions in the current period. This is called a rolling horizon concept. However, the details and results of this step are not shown in this paper. DISCUSSION AND CONCLUSION The ARIMA model provides more reliable demand forecasts but it is more complicated to apply than the decomposition model. Therefore the ARIMA model should be used only when the decomposition model is inadequate. When compared against those of the current practice of the company, the errors of our selected models are considerably lower. This situation can lead to substantial reductions in safety stocks. Consequently, the lower safety stocks result in decreased inventory holding and overtime costs. The results of the production planning model are of great value to the company since the model can determine the optimal overtime work, production quantities, and inventory levels that yield the optimal total overtime and holding costs. The production planning method is more suitable than the existing one that does not consider any cost factors. Moreover, it has been proven that an application of appropriate forecasting techniques can reduce total inventory holding and overtime costs significantly. In conclusion, this paper demonstrates that an improvement in demand forecasting and production planning can be achieved by replacing subjective and intuitive judgments by the systematic methods.

A Look at the History of Computers

A Look at the History of Computers Before the age of electronics, the closest thing to a computer was the abacus, although, strictly speaking, the abacus is actually  a calculator since it requires a human operator. Computers, on the other hand, perform calculations automatically by following a series of built-in commands called software. In the 20th century,  breakthroughs in technology allowed for the ever-evolving computing machines that we now depend upon so totally, we practically never give them a second thought. But even prior to the advent of microprocessors and supercomputers, there were certain notable scientists and inventors who helped lay the groundwork for the technology thats since drastically reshaped every facet of modern life. The Language Before the Hardware The universal language in which computers carry out processor instructions originated in the 17th century in the form of the binary numerical system. Developed by German philosopher and mathematician Gottfried Wilhelm Leibniz, the system came about as a way to represent decimal numbers using only two digits: the number zero and the number one. Leibnizs system was partly inspired by philosophical explanations in the classical Chinese text the â€Å"I Ching,† which explained the universe in terms of dualities such as light and darkness and male and female. While there was no practical use for his newly codified system at the time, Leibniz believed that it was possible for a machine to someday make use of these long strings of binary numbers.​ In 1847, English mathematician George Boole introduced a newly devised algebraic language built on Leibnizs work. His â€Å"Boolean Algebra† was actually a system of logic, with mathematical equations used to represent statements in logic. Equally important was that it employed a binary approach in which the relationship between different mathematical quantities would be either true or false, 0 or 1.   As with Leibniz, there were no obvious applications for Boole’s algebra at the time, however, mathematician Charles Sanders Pierce spent decades expanding the system, and in 1886, determined that the calculations could be carried out with electrical switching circuits. As a result, Boolean logic would eventually become instrumental in the design of electronic computers. The Earliest Processors English mathematician Charles Babbage is credited with having assembled the first mechanical computers- at least technically speaking. His early 19th-century machines featured a way to input numbers, memory, and a processor, along with a way to output the results. Babbage called his initial attempt to build the world’s first computing machine the â€Å"difference engine.† The design called for a machine that calculated values and printed the results automatically onto a table. It was to be hand-cranked and would have weighed four tons. But Babbages baby was a costly endeavor. More than  £17,000 pounds sterling was spent on the difference engines early development. The project was eventually scrapped after the British government cut off Babbage’s funding in 1842. This forced Babbage to move on to another idea, an analytical engine, which was more ambitious in scope than its predecessor and was to be used for general-purpose computing rather than just arithmetic. While he was never able to follow through and build a working device, Babbage’s design featured essentially the same logical structure as electronic computers that would come into use in the 20th century. The analytical engine had integrated memory- a form of information storage found in all computers- that allows for branching, or the ability for a computer to execute a set of instructions that deviate from the default sequence order, as well as loops, which are sequences of instructions carried out repeatedly in succession.   Despite his failures to produce a fully functional computing machine, Babbage remained steadfastly undeterred in pursuing his ideas. Between 1847 and 1849, he drew up designs for a new and improved second version of his difference engine. This time, it calculated decimal numbers up to 30 digits long, performed calculations more quickly, and was simplified to require fewer parts. Still, the British government did not feel it was worth their investment. In the end, the most progress Babbage ever made on a prototype was completing one-seventh of his first design. During this early era of computing, there were a few notable achievements: The tide-predicting machine, invented by Scotch-Irish mathematician, physicist, and engineer Sir William Thomson in 1872, was considered the first modern analog computer.  Four years later, his older brother, James Thomson, came up with a concept for a computer that solved mathematical problems known as differential equations. He called his device an â€Å"integrating machine† and in later years, it would serve as the foundation for systems known as differential analyzers. In 1927, American scientist Vannevar Bush started development on the first machine to be named as such and published a description of his new invention in a scientific journal in 1931. Dawn of Modern Computers Up until the early 20th century, the evolution of computing was little more than scientists dabbling in the design of machines capable of efficiently performing various kinds of calculations for various purposes. It wasn’t until 1936 that a unified theory on what constitutes a general-purpose computer and how it should function was finally put forth. That year, English mathematician Alan Turing published a paper titled, On Computable Numbers, with an Application to the Entscheidungsproblem, which outlined how a theoretical device called a â€Å"Turing machine† could be used to carry out any conceivable mathematical computation by executing instructions. In theory, the machine would have limitless memory, read data, write results, and store a program of instructions. While Turing’s computer was an abstract concept, it was a German engineer named Konrad Zuse who would go on to build the world’s first programmable computer. His first attempt at developing an electronic computer, the Z1, was a binary-driven calculator that read instructions from punched 35-millimeter film. The technology was unreliable, however, so he followed it up with the Z2, a similar device that used electromechanical relay circuits. While an improvement, it was in assembling his third model that everything came together for Zuse. Unveiled in 1941, the Z3 was faster, more reliable, and better able to perform complicated calculations. The biggest difference in this third incarnation was that the instructions were stored on an external tape, thus allowing it to function as a fully operational program-controlled system.   What’s perhaps most remarkable is that Zuse did much of his work in isolation. Hed been unaware that the Z3 was Turing complete, or in other words, capable of solving any computable mathematical problem- at least in theory. Nor did he have any knowledge of similar projects underway around the same time in other parts of the world. Among the most notable of these was the IBM-funded Harvard Mark I, which debuted in 1944. Even more promising, though, was the development of electronic systems such as Great Britain’s 1943 computing prototype Colossus and the ENIAC, the first fully-operational electronic general-purpose computer that was put into service at the University of Pennsylvania in 1946. Out of the ENIAC project came the next big leap in computing technology. John Von Neumann, a Hungarian mathematician whod consulted on ENIAC project, would lay the groundwork for a stored program computer. Up to this point, computers operated on fixed programs and altering their function- for example, from performing calculations to word processing. This required the time-consuming process of having to manually rewire and restructure them. (It took several days to reprogram ENIAC.) Turing had proposed that ideally, having a program stored in the memory would allow the computer to modify itself at a much faster pace. Von Neumann was intrigued by the concept and in 1945 drafted a report that provided in detail a feasible architecture for stored program computing.  Ã‚  Ã‚   His published paper would be widely circulated among competing teams of researchers working on various computer designs. In 1948, a group in England introduced the Manchester Small-Scale Experimental Machine, the first computer to run a stored program based on the Von Neumann architecture. Nicknamed â€Å"Baby,† the Manchester Machine was an experimental computer that served as the predecessor to the Manchester Mark I. The EDVAC, the computer design for  which Von Neumann’s report was originally intended, wasn’t completed until 1949. Transitioning Toward Transistors The first modern computers were nothing like the commercial products used by consumers today. They were elaborate hulking contraptions that often took up the space of an entire room. They also sucked enormous amounts of energy and were notoriously buggy. And since these early computers ran on bulky vacuum tubes, scientists hoping to improve processing speeds would either have to find bigger rooms- or come up with an alternative. Fortunately, that much-needed breakthrough was already in the works. In 1947, a group of scientists at Bell Telephone Laboratories developed a new technology called point-contact transistors. Like vacuum tubes, transistors amplify electrical current and can be used as switches. More importantly, they were much smaller (about the size of an aspirin capsule), more reliable, and they used much less power overall. The co-inventors John Bardeen, Walter Brattain, and William Shockley would eventually be awarded the Nobel Prize in physics in 1956. While Bardeen and Brattain continued doing research work, Shockley moved to further develop and commercialize transistor technology. One of the first hires at his newly founded company was an electrical engineer named Robert Noyce, who eventually split off and formed his own firm, Fairchild Semiconductor, a division of Fairchild Camera and Instrument. At the time, Noyce was looking into ways to seamlessly combine the transistor and other components into one integrated circuit to eliminate the process in which they had to be pieced together by hand. Thinking along similar lines, Jack Kilby, an engineer at Texas Instruments, ended up filing a patent first. It was Noyce’s design, however, that would be widely adopted. Where integrated circuits had the most significant impact was in paving the way for the new era of personal computing. Over time, it opened up the possibility of running processes powered by millions of circuits- all on a microchip the size of a postage stamp. In essence, it’s what has enabled the  ubiquitous handheld gadgets we use every day, that are ironically, much more powerful than the earliest computers that took up entire rooms.

Thomas Edisons Invention Factory in Menlo Park

Thomas Edison's Invention Factory in Menlo Park Thomas Edison was behind the formation of the first industrial research laboratory, Menlo Park, a place where a team of inventors would work together to create new inventions. His role in forming this invention factory gave him the nickname the Wizard of Menlo Park. Menlo Park, New Jersey Edison opened a research laboratory in Menlo Park, NJ, in 1876. This site later become known as an invention factory, since Edison and his employees worked on several different inventions at any given time there. It was there that Thomas Edison invented the phonograph, his first commercially successful invention. The New Jersey Menlo Park laboratory was closed in 1882, when Edison moved into his new larger laboratory in West Orange, New Jersey. The Wizard of Menlo Park Thomas Edison was nicknamed The Wizard of Menlo Park by a newspaper reporter after his invention of the phonograph while at Menlo Park. Other important achievements and inventions that Edison created at Menlo Park included: A carbon button transmitter (aka microphone) and the induction coil that greatly improved the telephoneAn improved bulb filament and successful incandescent light bulbThe first underground electrical systemA prototype electric railway was constructed at Menlo ParkThe founding of the Edison Electric Light CompanyChristie Street in Menlo Park became the worlds first street to be lit by incandescent light bulbs.In fact, Menlo Park became a tourist attraction because of the novelty of lighting.Edison applied for over 400 patents for inventions made at Menlo Park. The Land of Menlo Park Menlo Park was part of rural Raritan Township in New Jersey. Edison bought 34 acres of land there in late 1875. The office of a former real estate company, at the corner of Lincoln Highway and Christie Street, became Edisons home. Edisons father built the main laboratory building on the block south of Christie Street between Middlesex and Woodbridge Avenues. Also built was the glass house, a carpenters shop, a carbon shed, and a blacksmith shop. By the Spring of 1876, Edison moved his full operations to Menlo Park.

Ethnography Essay Example | Topics and Well Written Essays - 1000 words

Ethnography - Essay Example n which the members of this church maintain a close-knit, family relationship by examining worship practices, family relationships and subgroup relationships within the greater whole. The data for this analysis was collected over a period of weeks in which the author kept a journal of his observations while attending church. While the author was a participant in these proceedings, effort was made to step back and view the proceedings from the perspective of the outsider without sacrificing the insights available to the insider. Journal entries were made on a weekly basis beginning September 4, 2006 and ending October 23, 2006. There are approximately 250 listed members of this particular church, 230 of which attend on a regular basis. The members of the church range in ages from the very young to the very old, with a majority of the members falling within the middle age category. The congregation is also comprised of a wide variety of ethnicities, primarily Russian, Lebanese and Greek. The worship service itself functions as a reminder of a call to family togetherness. One of the first actions parishioners observe as they walk into the church is to light a candle in the Narthex in memory of a deceased relative or loved one – the author typically lights one in memory of a deceased uncle. They then kiss the icon and cross themselves on the chest three times before taking their places to ensure they are in proper frame of mind to receive the instruction to follow. The sermon, usually covering a topic that is loving and nonjudgmental, typically lasts approximately one hour. Following the sermon, the congregation files out, kissing the priest and the cross he holds as they pass. From here, most members of the congregation file into a large dining room in which they partake of foods brought in from individual members. Toward the end of the period of study, a young girl was baptized in a child-size plastic swimming pool that had obviously been purchased at