• The Pure and Applied Mathematics
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• v.3 no.2
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• pp.131-139
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• 1996

Topos is a set-like category. For an axiom of choice in a topos, F. W. Lawvere and A. M. Penk introduced another versions of the axiom of choice. Also it is showed that general axiom of choice and Penk's axiom of choice are weaker than Lawvere's axiom of choice. In this paper we study that weak form of axiom of choice, axiom of choice, Penk's axiom of choice and Lawvere's axiom of choice are all equivalent in a well pointed topos.

• The Korean Journal of Applied Statistics
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• v.25 no.5
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• pp.847-857
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• 2012

This article is concerned with choice-based conjoint analysis versus rating-based and ranking-based conjoint analysis. Choice-based conjoint analysis has a definite advantage in that the respondent's task of choosing the most preferred profile from several competing profiles adequately mimics consumer marketplace behavior. It is crucial to design the choice sets appropriate for the choice-based conjoint. Thus, this article suggests a new method to design the choice sets that are well-balanced. It augments the balanced incomplete block design and then obtains the dual design of the result to accommodate various numbers of profiles. In consequence, the choice sets designed by the new method have the desirable characteristics that each profile is presented to the same number of respondents, and pairs of any two distinct profiles occur together in the same number of choice sets. The balancing of the design increases the efficiency of the conjoint analysis. In addition, the pair-comparison scheme can improve the quality of data through the identification of contradictory responses.

• Journal of Korean Society of Transportation
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• v.11 no.2
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• pp.5-26
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• 1993

In order to analyze travel mode choice behavior, behavioral models including logit model, based on revealed preference theory, have been using easily measurable variables such as individual socioeconomic characteristics and physical attributes of travel modes. But some recent attitudinal models of travel choice behavior have implied that the negligence of individual psychological variables and individual choice constraints in travel mode choice might preclude better prediction of individual travel mode choice behavior. In this context, this study was attempted to reconstruct an attitudinal model(AM), especially focused on the decision rules in travel mode choice decision making process, consistent with the conceptual framework relating individual attitude and choice constraints to choice behavior. And to evaluate the strengths of the AM to other comparative models(logit, linear-additive, conjunctive, lexicographic model) in predicting travel mode choice bebavior, an empirical study of the mode choice in work-trip to CBD in Seoul was performed. According to the results the percent of correct prediction(PCP) derived from the AM was higher than those derived from comparative models by at least 7 to 20% in predicting travel mode choice. But each model produced a different prediction accuracy depending on market segmentation by travel modal users, individual socioeconomic characteristics, transportation system characteristics, and satisfaction levels. The finding that different groups divided by a certain criterion employ different decision rules supports the necessity of developing a choice model such as the AM combining compensatory and noncompensatory decision rules, and suggests that a proposed transportation system management plan or policy may have different effects on each group.

• Journal of Korean Society of Transportation
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• v.7 no.1
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• pp.35-42
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• 1989

The multinomial logit model has been applied for various choice problems. Among others, the joint destination mode choice, the mode choice and the route choice are the three major modeling topics for korean transportation planners. This paper examines with real world data (the Olympic road and its competing two major arterials) the usefulness of a Logit route choice model. Quites surpisingly, it is found that the multinomial route choice behavioral model calibrated for this study based on (0,1) individula data base can not provide a good estimate for O-D trips less than 6㎞. 400data points and 3case studies might not be sufficient for a sound conclusion. It is, however, believed from a series of similar studies conducted by the authors that the route choice behavior is more sensitive (more demand elastic with respect to travel time changes) than the mode choice and the shorter trip, the more sensitive. The travel time parameters for destination choice models are usually smalle than the travel time parameters for mode choice models and these parameters (for mode choice models) turn our smaller than the travel time parameters for route choice models from this study. Table 2 in this paper shows parameter changes for three different markets and Table 3 shows the modeling errors when the estimated individual probabilities are aggregated into a route level.

• Communications of the Korean Mathematical Society
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• v.19 no.1
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• pp.29-34
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• 2004

There are various forms of the axiom of choice and also various weak forms of the axiom of choice in a topos. This paper give equivalent forms of the axiom of choice in a well-pointed topos.

• Culinary science and hospitality research
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• v.13 no.4
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• pp.186-198
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• 2007

Recently, the desire of the students has been changing variously as time passes and its speed is being accelerated. In this respect, this paper aims to demonstrate college students' menu choice behavior. In order to attain the object of this paper, college students in Chung-Nam Province including Daejeon city have been studied. There are many kinds of manu choice factors in food-industry. One of the methods of this study is Khan's food choice factor. The results of this analysis suggest that hypothesis 1-1, the environmental factors for college students were verified as significant effects on menu choice behavior of other people and also hypothesis $1{\sim}2$, self oriented for menu choice behavior showed significant effects. As a result, Khan's food choice behavior should be comparative to each factor focused on diversified environments. And also each factor is not strongly affected in relation to food choice factor. Therefore, students' menu choice behavior will be measured by verifying factors.

• The Pure and Applied Mathematics
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• v.15 no.1
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• pp.85-92
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• 2008

In topoi, there are various forms of the axiom of choice such as (ES), (AC) and (WO). And also there are various weak forms of the axiom of choice such as (DES), (IAC) and (ASC). First we investigate the relation between (IAC) and (ASC), and then we study the relation between (AC) and (WO). We get equivalent forms of the axiom of choice in a well-pointed topos.

• Asia-Pacific Journal of Business
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• v.1 no.2
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• pp.23-46
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• 2010

Despite the explosive growth of no-frill airline industry, very little is known about how consumers make purchase decision in such settings. Today's airline industry requires choice models consistent with consumers' true preference sets. This study used conjoint analysis to identify these ideal choice models. 38 percent of the subjects were found to use compensatory and 62 percent non-compensatory models. Our findings suggest a need to base choice-making promotions on ideal choice models if the promotion is to lead consumers to decisions consistent with true preferences.

• Korean Journal of Health Education and Promotion
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• v.28 no.2
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• pp.41-50
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• 2011

Objectives: Objectives: The objective of this study is to describe the WHO-CHOICE(World Health Organization- CHOosing Interventions that are Cost-Effective) programme, and to consider the application of WHO-CHOICE programme in Korea, especially on the health promotion policy. Methods: Literature review was conducted on the contents of WHO-CHOICE programme in the previous studies, guidebook, and software. We also contacted WHO-CHOICE team at WHO to identify the contents not clearly presented in the documents. Results: The WHO-CHOICE programme is a standardized tool for analyzing and comparing the cost effectiveness of health promotion policies. It is composed of PopMod to measure the health effect of intervention and of CostIt to measure the cost. The cost of tobacco control policy in Korea was analyzed with the cooperation of WHO-CHOICE team preliminary, and the results were different with the results of tobacco control policy on western pacific region of WHO. Conclusions: The cost effectiveness study based on WHO-CHOICE programme could help decide a priority of health promotion policy for settings with limited resources. For the improvement of health, the future work on WHO-CHOICE programme need to be considered.

• Journal of KIISE
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• v.43 no.5
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• pp.541-552
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• 2016

This paper introduces the new notions of conjunctive and complement choices in process algebra, which reduce both process and system complexities significantly for distributed mobile real-time system during specification and analysis phases. The complement choice implies that two processes make cohesive choices for their synchronous partners at their own choice operations. The conjunctive choice implies choice dependency among consecutive choice operations in a process. The conjunctive choice reduces process complexity exponentially by the degree of the consecutive choice operations. The complement choice also reduces system complexity exponentially by the degree of the synchronous choice operations. Consequently, the reduction method makes the specification and analysis of the systems much easier since the complexity is reduced significantly. This notion is implemented in a process algebra, called ${\delta}$-Calculus. The efficiency and effectiveness are demonstrated with an example in a tool for the algebra, called SAVE, which is developed on ADOxx platform.