• Title/Summary/Keyword: Individual Constraints

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Estimating Outbreak Probabilities of Systems and Components with Masked Data (마스크 데이터를 이용한 컴포넌트의 고장발생확률 추정)

  • 박창규
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.25 no.6
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    • pp.7-11
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    • 2002
  • This paper estimates defect and outbreak probabilities of each individual component from some subset of masked data where the exact component causing system failure might be unknown. A system consists of k components that fails whenever there is a defect in at least one of the components. Due to cost and time constraints it is not feasible to learn exactly which components are defective. Because, test procedures ascertain that the defective components belong to some subset of the k components. This phenomenon is termed masking. We describe a, b, c type in which a sample of masked subsets is subjected to intensive failure analysis. This recorded data of a, b, c type enables maximum likelihood estimation of defect probability of each individual component and leads to outbreak of the defective components in future masked failures.

A case of corporate failure prediction

  • Shin, Kyung-Shik;Jo, Hongkyu;Han, Ingoo
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1996.10a
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    • pp.199-202
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    • 1996
  • Although numerous studies demonstrate that one technique outperforms the others for a given data set, there is often no way to tell a priori which of these techniques will be most effective to solve a specific problem. Alternatively, it has been suggested that a better approach to classification problem might be to integrate several different forecasting techniques by combining their results. The issues of interest are how to integrate different modeling techniques to increase the prediction performance. This paper proposes the post-model integration method, which means integration is performed after individual techniques produce their own outputs, by finding the best combination of the results of each method. To get the optimal or near optimal combination of different prediction techniques. Genetic Algorithms (GAs) are applied, which are particularly suitable for multi-parameter optimization problems with an objective function subject to numerous hard and soft constraints. This study applied three individual classification techniques (Discriminant analysis, Logit and Neural Networks) as base models to the corporate failure prediction context. Results of composite prediction were compared to the individual models. Preliminary results suggests that the use of integrated methods will offer improved performance in business classification problems.

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The Hybrid Systems for Credit Rating

  • Goo, Han-In;Jo, Hong-Kyuo;Shin, Kyung-Shik
    • Journal of the Korean Operations Research and Management Science Society
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    • v.22 no.3
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    • pp.163-173
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    • 1997
  • Although numerous studies demonstrate that one technique outperforms the others for a given data set, it is hard to tell a priori which of these techniques will be the most effective to solve a specific problem. It has been suggested that the better approach to classification problem might be to integrate several different forecasting techniques by combining their results. The issues of interest are how to integrate different modeling techniques to increase the predictive performance. This paper proposes the post-model integration method, which tries to find the best combination of the results provided by individual techniques. To get the optimal or near optimal combination of different prediction techniques, Genetic Algorithms (GAs) are applied, which are particularly suitable for multi-parameter optimization problems with an object function subject to numerous hard and soft constraints. This study applies three individual classification techniques (Discriminant analysis, Logit model and Neural Networks) as base models for the corporate failure prediction. The results of composite predictions are compared with the individual models. Preliminary results suggests that the use of integrated methods improve the performance of business classification.

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Virtuality as a Psychological Distance and Temporal Distance: Focusing on the Effect of Product Information Type on Product Attitude (심리적 거리로서의 가상성과 시간적 거리: 제품 정보 유형의 제품 태도에 미치는 효과를 중심으로)

  • Park, Do-Hyung
    • Knowledge Management Research
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    • v.18 no.3
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    • pp.163-178
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    • 2017
  • Recent advances in technology are evolving to enable individuals to perform various activities necessary for their lives, without being constrained by physical, temporal, and spatial constraints. The online services and experiences that originated from solving the discomfort in the actual offline space have created the newness that can only be experienced in the digital world and furthermore uniquely new experiences in actual space as well. While many previous studies have suggested several interpretations of unique individual behaviors in virtual environments, a recent research approaches virtuality as an interesting perspective of the change of thinking style. Virtuality is defined as how far apart we are from everyday reality, and if the individual faces a situation far from reality, the psychological distance of the individual becomes distant and ultimately leads to the thinking style of high construal level. Otherwise, it is said to have a relatively low construal level of thinking style. In this study, I try to confirm the virtual distance as the role of psychological distance in new virtual contexts. Simultaneously considering temporal distance, which are most used in psychological distance, and virtual distance based on virtuality, this study tries to find whether the effect of virtual distance on product attitude is the same as that of temporal distance and check the relationship between virtual distance and temporal distance in the context of consumers' product evaluations depending on product information type.

Beyond Factual Knowledge and Symbolic Competence: Interculturality as Transcultural Intersubjectivity

  • Omengele, Theophile Ambadiang
    • Cross-Cultural Studies
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    • v.20
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    • pp.295-321
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    • 2010
  • The trend of globalization has sharpened the debate on interculturality, which scholars examine from different and often conflicting points of view ('content' vs. 'practice', 'culture-specific' vs. 'universal', 'communication (meta)theory' vs. 'communication practice', 'individual' vs. 'collective', etc.). Whereas all these approaches are necessary to describe the multiple dimensions of interculturality, their dichotomous nature does not help to account for its internal complexity, which cannot be dissociated from the connections that exist among all these dimensions. The difficulty posed by the essentialist interpretations that tend to result from these dichotomies is compounded by the fact that in postmodern debates priority has been given to approaches that emphasize individual or collective agency over structural constraints which have to do with political economy or with cultural and linguistic codes and traditions. This paper aims mainly at suggesting that the dissolution of the boundaries that exist between these approaches should be pursued in order to get a fuller and richer approach to their common object of study. After discussing, by way of illustration, content-based and practice-based perspectives, we suggest that one way of getting beyond these dichotomies consists in focusing on the 'interactional' dimension of interculturality, which means laying emphasis on intersubjectivity and, particularly, on the individual subjects considered as members of different cultural communities who strive to transcend their sociocultural boundaries in order to reach harmonious interactions in a world in which inequality and the de-territorialization of people and cultures are central features.

Effects of Internal Family Systems Therapy Program to Increase Ego-Identity of Middle-Aged Women (내적가족체계치료 프로그램이 중년여성의 자아정체감 증진에 미치는 효과)

  • Byeon, Wei-Jin;Kim, Choon-Kyung
    • Journal of Families and Better Life
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    • v.25 no.5
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    • pp.47-63
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    • 2007
  • The purpose of this study was to verify the effectiveness of an internal family systems therapy program aimed at increasing ego-identity of middle-aged women. The objectives of this program were for middle-aged women to differentiate the self of internal systems, to identify constraints impinging on an individual part, to release constraints impinging on an individual part, to harmonize the internal family, and to enhance ego-identity. 31 middle-aged women ranged in age from 40 to 60. Two groups were identified as equivalents for the study in the pre-test. The program of this experimental group was implemented twice a week for 120 minutes per each session over a 6-week period. The pre-test(Aug. 29. 2006), the post-test(Oct. 20. 2006) and the follow-up test(Nov. 20. 2006) were implemented in order to verify the effectiveness of the programs. The participants who were absent more than three times in the program were excluded from the post-test and follow-up test. Eventually, the data in 31 persons(15 for the internal family systems therapy, 16 for the control group) were analyze to verify the effectiveness of the program. The instruments used in the study were the ego-identity scale. The data were analyzed using repeated measures ANOVA, simple main effect, post-hoc t-test, means and standard deviations. And the program was from Sep. 5. to Oct. 20. 2006. The findings of the study were as follows: The internal family systems therapy program had significant effects on enhancing the ego-identity. There was a large increase of the ego-identity in the intervention group, compared with control group at post treatment and follow-up after 1 month which indicated the continuity of intervention effect. However, in the control group, there were no changes according to the time.

Remote control of individual modules based on mobile phone and web (모바일 폰과 웹을 연동한 개별모듈 원격제어)

  • Park, Sang-Gug
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.4
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    • pp.780-788
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    • 2011
  • This paper suggests one model, which can be monitor and control target system at anytime and anywhere by a WAP and ME based personal cellular phone(Feature phone) and internet connection. The suggesting model tried to overcome constraints of distance and mobility of conventional methods, TCP/IP based remote data monitoring system, which combine PDA and WLAN technologies. For the experiments of suggesting model, the target systems are constructed with individual modules, which need AC or DC power control. The development software for the control and monitor of local system use NI Labview for the easy-programming and confidence. Also, web server use APM setup for the general user. The mobile connection environments of personal cellular phone are programmed by use WML and mHTML language for the general access. Through the experiments, we have showed that suggesting model can overcome constraints of distance and mobility of conventional system.

A Study on the Implementation of Dose Constraints in Occupational Dose According to ICRP 103 Recommendations in Korea (ICRP신권고에 따른 직무피폭에서의 선량제약치 국내 적용 방안 연구)

  • Kim, Yong-Min;Cho, Kun-Woo
    • Journal of Radiation Protection and Research
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    • v.36 no.3
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    • pp.127-133
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    • 2011
  • In 2007, the International Commission on Radiological Protection (ICRP) published Recommendations of the International Commission on Radiological Protection. Accordingly IAEA safety standards committees have reviewed and revised the BSS. The process of the implementation of the ICRP 103 into Korean radiation protection regulations has been continued. Although the new recommendations retain the fundamental protection principles, the impact of the new ICRP recommendations will necessarily be greater than ever before. ICRP recommends the application of dose constraint in planned situations and reference level in existing & emergency situations for strengthening of the principle of optimization. Dose constraints and reference level play a criterion on the level of individual dose as prospective and source-related values. Therefore it is necessary to apply dose constraints and reference levels to all nuclear and RI&RG facilities in Rep. of Korea. Dose constraints and reference level of occupational exposure will be set-up by the stakeholder itself with the cooperation of regulatory body. In this study, the implementation method was discussed to apply the dose constraints and reference level as the procedure for the optimization, not the tool of the regulation.

A Study on the Optimization Method using the Genetic Algorithm with Sensitivity Analysis (민감도가 고려된 알고리듬을 이용한 최적화 방법에 관한 연구)

  • Lee, Jae-Gwan;Sin, Hyo-Cheol
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.6 s.177
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    • pp.1529-1539
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    • 2000
  • A newly developed optimization method which uses the genetic algorithm combined with the sensitivity analysis is presented in this paper. The genetic algorithm is a probabilistic method, searching the optimum at several points simultaneously, requiring only the values of the object and constraint functions. It has therefore more chances to find global solution and can be applied various problems. Nevertheless, it has such shortcomings that even it approaches the optimum rapidly in the early stage, it slows down afterward and it can't consider the constraints explicitly. It is only because it can't search the local area near the current points. The traditional method, on the other hand, using sensitivity analysis is of great advantage in searching the near optimum. Thus the combination of the two techniques makes use of the individual advantages, that is, the superiority both in global searching by the genetic algorithm and in local searching by the sensitivity analysis. Application of the method to the several test functions verifies that the method suggested is very efficient and powerful to find the global solutions, and that the constraints can be considered properly.

An Extension of SWCL to Represent Logical Implication Knowledge under Semantic Web Environment (의미웹 환경에서 조건부함축 제약 지식표현을 위한 SWCL의 확장)

  • Kim, Hak-Jin
    • Journal of the Korean Operations Research and Management Science Society
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    • v.39 no.3
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    • pp.7-22
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    • 2014
  • By the publications of RDF and OWL, the Semantic Web is confirmed as a technology through which information in the Internet can be processed by machines. The focus of the Semantic Web study after then has moved to how to provide more useful information to users for their decision making beyond simple use of the structured data in ontologies. SWRL that makes logical inference possible by rules, and SWCL that formulates constraints under the Semantic Web environment are some of many efforts toward the achievement of that goal. Constraint represents a connection or a relationship between individual data in ontology. Based on SWCL, this paper tries to extend the language by adding one more type of constraint, implication constaint, in its repertoire. When users use binary variables to represent logical relationships in mathematical models, it requires and knowledge on the solver to solve the models. The use of implication constraint ease this difficulty. Its need, definition and relevant technical description is presented by the use of the optimal common attribute selection problem in product design.