• Title/Summary/Keyword: desirability

Search Result 261, Processing Time 0.028 seconds

OPTIMIZATION OF WELDING PARAMETERS FOR RESISTANCE SPOT WELDING OF TRIP STEEL USING RESPONSE SURFACE METHODOLOGY

  • Park, Hyunsung;Kim, Taehyung;Sehun Rhee
    • Proceedings of the KWS Conference
    • /
    • 2002.10a
    • /
    • pp.366-371
    • /
    • 2002
  • Because of the environmental problems, automotive companies are trying to reduce the weight of car body. Therefore, TRIP(TRansformation Induced Plasticity) steels, which have high strength and ductility have been developed. Welding process is a complex process; therefore deciding the optimal welding conditions on the basis of experimental data is an effective method. However, trial-and-error method to decide the optimal conditions requires too many experiments. To overcome these problems, response surface methodology was used. Response surface methodology is a collection of mathematical and statistical techniques that are used in the modeling and analysis of problems in which a response of interest is influenced by several variables and the objective is to optimize this response. This method was applied to the resistance spot welding process of the TRIP steel to optimize the welding parameters.

  • PDF

Parental Loss Experiences of College Students (부모 사별에 따른 대학생의 상실경험 연구)

  • Yang, Sung-Eun
    • Journal of Families and Better Life
    • /
    • v.26 no.5
    • /
    • pp.39-49
    • /
    • 2008
  • This research reports on a qualitative analysis of email facilitated reflective dialogue with seven college students whose parent dies. The study was exploratory in considering cultural values on intact family and asked the question: What do children experience after parental death in terms of the relationships with intra and extrafamily systems? Young adult children of single parent family expressed that they felt social pressure to practice filial piety toward their single parent. They made efforts to fulfill the social expectation and to achieve social desirability. Social stigma from extrafamily systems affected the experiences of the bereaved children. In terms of intrafamily system, young adult children tend to idealize their deceased parent. Single parents depended on the young adult children, which made parent-child relationship enmeshed or conflicting. The holistic view of the study highlights the importance of interactions between individuals and the intra and extra family systems when understanding family loss experience of the bereaved young people.

A Study on Multiple Response Optimization for Robust Design using Desirability Function

  • Kwon, Yong-Man;Chang, Duk-Joon;Hong, Yeon-Woong
    • 한국데이터정보과학회:학술대회논문집
    • /
    • 2003.05a
    • /
    • pp.65-75
    • /
    • 2003
  • In the Taguchi parameter design, the product array approach using orthogonal arrays is mainly used. However, it often requires an excessive number of experiments. An alternative approach, which is called the combined array approach, was suggested by Welch et. al. (1990) and studied by others. In these studies, only single response variable was considered. We propose how to simultaneously optimize multiple responses when we use the combined array approach.

  • PDF

Eating Qualities of Frozen Cooked Rice on the Thawing Condition (해동조건에 따른 냉동밥의 밥맛 비교)

  • 오명숙
    • Journal of the Korean Home Economics Association
    • /
    • v.35 no.2
    • /
    • pp.147-157
    • /
    • 1997
  • It attempted to determine the effect of various thawing methods, such as pressure cooking, conventional cooking, microwave heating and thawing at room temperature, on the quality of frozen cooked rice using Nongan variety of rice. These effects were analysed at three different periods-after 10 days, 30 days and 90 days. It conducted a physico-chemical analysis(moisture content, dehydration rates, color value and texture) and sensory evaluation o the frozen-thawed cooked rice. The study showed that there were no significant differences on the frozen-thawed cooked rice. The study showed that there were no significant differences on the quality characteristics of frozen-thawed cooked rice during the storage of 90 days. However, the thawing method of pressure cooking caused high moisture content and decrease in hardness on the cooked rice, the desirability for the rice didn't diminish compared with the cooked rice just after cooking. the quality characteristics of the cooked rice after frozen-thawing by conventional cooking and microwave heating were similar with that of the cooked rice just after cooking. thawing at room temperature caused a significant decrease in quality characteristics.

  • PDF

Development of Anti-viral Agents from Natural Sources

  • Hattori, Masao
    • Plant Resources
    • /
    • v.4 no.3
    • /
    • pp.192-195
    • /
    • 2001
  • Human immunodeficiency virus (HIV), the causative agent of AIDS, still continues to spread rapidly in the world population, especially in Africa and Southeast Asia. At present, two kinds of therapeutic approaches are used for treatment of AIDS. One is to target HIV reverse transcriptase, which is responsible for the viral genome transcription. The other is to inhibit HIV pretense PR, which is essential for the processing of viral proteins. Drug combinations based on these approaches can reduce the blood virus to an undetectable level. However, a small amount of virus may lurk inside the immune cells in a dormant state. Another major obstacle of long-term treatment of the disease is remarkable mutation in HIV. Most of the clinical chemotherapeutic agents have one or more of these problems. High cost and harmful side-effects further reduced the desirability of these drugs. In the course our studies on development of anti-HIV agents from natural products, we investigated various crude drugs for their inhibitory activity against HIV-induced cytopathic effects (CPE) in culture cells, HIV-pretense (PR), HIV-reverse transcriptase (RT) including ribonuclease H (RNase H), and HIV integrase (INT). In the present paper, some inhibitory substances relating to the development of anti-HIV agents are reported.

  • PDF

The Optimization of Jelly with Blueberry Juice using Response Surface Methodology (반응표면분석법을 이용한 블루베리 즙 첨가 젤리의 최적화)

  • Joo, Na-Mi;Kim, Bo-Ram;Kim, Ae-Jung
    • The Korean Journal of Food And Nutrition
    • /
    • v.25 no.1
    • /
    • pp.17-25
    • /
    • 2012
  • 이 연구는 블루베리 즙을 첨가하여 젤리의 제조조건을 최적화하고자 하였다. 16개의 블루베리 즙을 이용한 젤 시료는 Design Expert 프로그램을 이용하여 제조하였으며, 최적화를 위해 블루베리 즙(100~200 g), 설탕(40~160 g), 젤라틴(8~20 g)의 양을 독립변수로, 텍스처, pH, 관능평가 항목을 종속변수로 각각 선정하였다. 반응표면 분석법을 사용하기 위한 실험설계로 중심합성계획을 이용하였다. 각 항목별 최적조건은 Canonical 모형의 수치 최적화(numerical optimization)과 모형적 최적화(graphical optimization)를 통하여 선정하였으며, 그 중 가장 높은 desirability를 갖는 최적점을 선택하여 지점 예측(point prediction)을 통해 도출한 결과, 각 독립변수의 예측된 블루베리 즙을 첨가한 젤리의 최적값은 블루베리 주스 133.63 g, 설탕 160.0 g, 젤라틴은 12.78 g이었다.

Effects of the Position of Demographic Questions on Survey Responses

  • Heo, Sun-Yeong
    • Journal of the Korean Data and Information Science Society
    • /
    • v.15 no.4
    • /
    • pp.855-866
    • /
    • 2004
  • In many surveys, one of the most important goals is to obtain reliable and valid responses from respondents. To achieve the goal, a researcher have to make efforts to protect respondents' confidentiality and to reduce the effects of social desirability on answers. The key question of this paper is whether the position of demographic questions have an effect on responses. Two types of questionnaires are considered: one puts the demographic questions at the beginning and the other does at the last. On both types, I asked only a small number of demographic questions which are considered as essential on analytic purposes. The results show no evidence of position effects when the risk to threat confidentiality was minimized.

  • PDF

Global Economic Governance Reform and the Role of Asia: Opportunities Offered by the G20

  • Cho, Yoon Je
    • East Asian Economic Review
    • /
    • v.16 no.1
    • /
    • pp.3-23
    • /
    • 2012
  • The recent global financial crisis has highlighted the importance of international monetary and financial system reform. The current system is deemed to be no longer adequate to meet the needs of a complex, integrated world economy. With regards to the reform of the international monetary system, there have been various proposals both in demand and supply sides. These include proposals to build a stronger global financial safety net, to diversify the supply of international reserve currency and so on. These proposals face trade-offs between desirability and political feasibility. Given this situation, a practical transition would be to strengthen policy coordination among the major economies and to reform the International Monetary Fund. The success on both fronts depends heavily on global economic governance reform and the role of the G20. Increased status and representation of Asian countries in the G20 give both privileges and responsibilities to Asians. To meet these responsibilities, Asians should put forth greater efforts to develop their intellectual leadership in global economic issues through creating new forum and institutions.

  • PDF

The Parameter Design of Multiple Characteristics with Engineer's Opinions (전문가 의견을 고려한 다특성치 파라미터 설계에 관한 연구)

  • Cho, Yong-Wook;Park, Myeong-Kyu
    • Journal of Korean Society for Quality Management
    • /
    • v.27 no.2
    • /
    • pp.218-236
    • /
    • 1999
  • The purpose of parameter design is to determine optimal settings of design parameters of a product or a process such that the performance characteristics of a product exhibit small variabilities around their target values. Taguchi made significant contributions in this area. However, his analysis of the problem focused on only one performance characteristic or response, although in product and process design, multiple characteristics are more common. The critical problem in dealing with multiple characteristics is how to compromise the conflict among the selected levels of the design parameters for each individual characteristic. In this paper, Methodology using SN ratio optimized by univariate technique is proposed and a parameter design procedure to achieve the optimal balance among several different response variables is developed. Existing case studies are solved by the proposed method and the results are compared with ones by the sum of SN ratios, the expected weighted loss, the desirability function, and EXTOPSIS model.

  • PDF

A Study on the Parameter Design of Multiple Characteristics Considering Characteristical Importance (특성치 중요도를 고려한 다중특성치 파라미터 설계에 관한 연구)

  • 김용범;조용욱;김우열
    • Journal of the military operations research society of Korea
    • /
    • v.25 no.2
    • /
    • pp.62-72
    • /
    • 1999
  • Taguchi´s parameter design is to determine the optimal settings of design parameters of a product or a process such that the characteristics of a product exhibit small variabilities around their targer values. His analysis of the problem has focused only on a single characteristic or response. However the quality of most products is seldom defined by a characteristic, and is rather the composite of a great number of characteristics which are often interrelated and nearly always measured in a variety of units. The critical problem in dealing with multiple characteristics is how to compromise the conflict among the selected levels of the design parameters for each individual characteristic. In this paper, Methodology using SN ratio optimized by unvariate technique is proposed and a parameter design procedure to achieve the optimal compromise among several different response variables is developed. One existing case study is solved by the proposed method and the results are compared with ones by the sum of SN ratios, the expected weighted loss, the desirability functions, and EXTOPSIS model.

  • PDF