• Structural Engineering and Mechanics
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• v.60 no.6
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• pp.1093-1117
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• 2016

Global sensitivity analysis (GSA) has been widely used to investigate the sensitivity of the model output with respect to its input parameters. In this paper a new single-solution search optimization algorithm is developed based on the GSA, and applied to the size optimization of truss structures. In this method the search space of the optimization is determined using the sensitivity indicator of variables. Unlike the common meta-heuristic algorithms, where all the variables are simultaneously changed in the optimization process, in this approach the sensitive variables of solution are iteratively changed more rapidly than the less sensitive ones in the search space. Comparisons of the present results with those of some previous population-based meta-heuristic algorithms demonstrate its capability, especially for decreasing the number of fitness functions evaluations, in solving the presented benchmark problems.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.2
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• pp.138-145
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• 2016

This paper proposes an improved tabu search method for subset selection in multiple linear regression models. Variable selection is a vital combinatorial optimization problem in multivariate statistics. The selection of the optimal subset of variables is necessary in order to reliably construct a multiple linear regression model. Its applications widely range from machine learning, timeseries prediction, and multi-class classification to noise detection. Since this problem has NP-complete nature, it becomes more difficult to find the optimal solution as the number of variables increases. Two typical metaheuristic methods have been developed to tackle the problem: the tabu search algorithm and hybrid genetic and simulated annealing algorithm. However, these two methods have shortcomings. The tabu search method requires a large amount of computing time, and the hybrid algorithm produces a less accurate solution. To overcome the shortcomings of these methods, we propose an improved tabu search algorithm to reduce moves of the neighborhood and to adopt an effective move search strategy. To evaluate the performance of the proposed method, comparative studies are performed on small literature data sets and on large simulation data sets. Computational results show that the proposed method outperforms two metaheuristic methods in terms of the computing time and solution quality.

• 한국산학경영학회:학술대회논문집
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• 2005.11a
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• pp.1-9
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• 2005

Job search research has been criticized for failing to study the dynamics and change of the job search process. A lot of previous researches have used cross-sectional designs and treated job search as a static process. As a result, job search research has failed to examine how job seekers' behaviors change during the course of their search. This paper examined changes In job search behaviors(preparatory and active job search behavior, and job search intensity) and the effects of individual difference variables(self-esteem, self-efficacy, extroversion, agreeableness, conscientiousness, openness) on job search behaviors. Data were gathered from 404 university students who had not found employment at the time of beginning of second semester The results of t-test pairs indicated that job seeking students increased their preparatory job search behavior and active job search behavior, but didn't job search intensity. The results of multiple regression showed that self-efficacy had strong relationship with preparatory and active job search behavior, and job search intensity, but self-esteem had not any relationship with them. Among big-5 personality, extroversion had relationship with active job search behavior and job search intensity, and agreeableness only with job search intensity.

• Journal of Agricultural Extension & Community Development
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• v.8 no.2
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• pp.201-208
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• 2001

The purpose of this study was to review the current studies on community attachment and its related variables to suggest directions for community attachment studies in Korea. Specific objectives of the study were to search the current studies on community attachment, to search for the significant variables related to community attachment, and to draw implications for community development in Korea. The major findings of the study were as follows; 1) Current studies on community attachment used individual characteristic variables such as length of residence in the community, age, size of population and density as major independent variables. 2) Studies on community attachment used community participation, social and cultural environment as major dependent variables, however, both independent variables and dependent variables were used interchangeably in many cases. 3) Recent studied on community attachment employed community economic and cultural variables, however, studies on community attachment in Korea was relatively limited in terms of quantity as well as quality. 4) Further research on community attachment should be conducted by utilizing various independent and dependent variables in various communities to increase the community attachment in rural and urban communities to further strengthen community development in Korea.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.95-98
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• 1996

Universal Learning Network(U.L.N.), which can model and control the large scale complicated systems naturally, consists of nonlinearly operated nodes and multi-branches that may have arbitrary time delays including zero or minus ones. Therefore, U.L.N. can be applied to many kinds of systems which are difficult to be expressed by ordinary first order difference equations with one sampling time delay. It has been already reported that learning algorithm of parameter variables in U.L.N. by forward and backward propagation is useful for modeling, managing and controlling of the large scale complicated systems such as industrial plants, economic, social and life phenomena. But, in the previous learning algorithm of U.L.N., time delays between the nodes were fixed, in other words, criterion function of U.L.N. was improved by adjusting only parameter variables. In this paper, a new learning algorithm is proposed, where not only parameter variables but also time delays between the nodes can be adjusted. Because time delays are integral numbers, adjustment of time delays can be carried out by a kind of random search procedure which executes intensified and diversified search in a single framework.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.3
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• pp.502-511
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• 1996

While much research on brand loyalty have been conducted until now, little has been challenged to integrate the results of previous (studies and how the brand loyalty is developed. The purpose of this study was to) suggest and test the model of clothing brand loyalty formation via consideration of all related variables simultaneously using the LISREL. The subjects were 505 male and female college graduates or higher white collar workers in their twenties and thirties living in Seoul, Korea. The data were collected by self- administered questionnaires. The results showed that consumer knowledge, product involvement, and perceived risk are positively related to information search. However, the influence of perceived risk on information search is statistically insignificant. Product involvement is also positively related to consumer satisfaction. Information search and consumer satisfaction are positively related to brand loyalty, respectively. In conclusion, consumer knowledge, product involvement, and perceived risk have positive influences on brand loyalty through the mediating variables of information search and consumer satisfaction.

• Journal of the Korean Geotechnical Society
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• v.25 no.9
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• pp.93-100
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• 2009

A core procedure of the direct search method used in this study is optimizing a difference between objective function and real displacement and correcting unknown variables. Because the research procedure comes from back-analyzing of the unknown variable of each layer, back-analyzing results need an additional optimization to minimize interferential effects of unknown variables. Therefore, the direct search method Is used to obtain optimized solutions without a partial differentiation of an objective function. The object of this research is developing the back analysis technique for multi-unknown variables by modeling the soil including underground structure Into upper and lower layer. In order to minimize interferent errors, repeated back analysis is performed and applicability on the real tunnel is examined. Consequently, the multi-layer analysis model is more precise in describing the real behavior of underground structure. It shows the validity of back analysis far multi-layer model which is the understructure placed on multi-layer boundaries.

• Journal of the Korean Home Economics Association
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• v.32 no.5
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• pp.67-82
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• 1994

The major purpose of this study was to find the influencing factors in explaining information search patterns and to find if significant differences exist in search outcomes by search patterns. The data for this study were collected in a survey conducted in March of 1993. The final sample consisted of 327 respondents purchased refrigerator 340 purchased bed. The important findings of this study are as follows: First The variables related to search cost-benefit play an important role in identifying search patterns of consumers. Second search outcomes were different among four information search patterns for each of information sources. The overall search outcomes the level of purchase knowledge and of post-purchase satisfaction was relatively high for high-search and high-reliance group compared with other groups. And the results also indicate that although some consumers search less than others they still can make good purchase decision-making and can maximize their utility if they choose useful information sources selectively and use those selected information sources effectively. The findings of this study provide some implications regarding consumer education programs the consumer information providing policies and future research methods.

• Korean Journal of Human Ecology
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• v.7 no.1
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• pp.61-74
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• 1998

The purpose of this study is to investigate the information search, information use and search outcomes. 420 students in Chungnam and Taejon area were surveyed. Questionnaire survey method and multiple regression and path analysis were used. Some major conclusions were as follows: 1) The levels of the information search, information use and search outcomes were relatively low. 2) The volumes of information search and the contents of information were mainly affected by psycho-behavioral variables. 3) The level of information use was affected by the content of information, desire to seek information, involvement, and previous knowledge. 4) The search outcome was affected positively by the information use, involvement, volume of information search, desire to seek information, and perceived risk. 5) The volume of information search and the information use were the parameter of the search outcomes.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.7
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• pp.1046-1055
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• 2008

The purpose of this study is to investigate the effects of product variables(i.e., fashionability, brand fame) and situational variables(i.e., time constraint, usage occasion) on the internet browsing behavior (i.e., prepurchase search; ongoing search for products, stores, fashion trends, promotions, and post-purchasing information) for fashion products. This study developed hypothetical scenarios based on the factorial design of the two independent variables for the survey with a questionnaire. All items in the questionnaire were measured on a six-point scale. By convenience sampling and on-line survey, a total of 209 usable responses were used for further analyses. The results show as follows; firstly, respondents more intensively browse for information search on products, stores and fashion trends when the style of browsing products is trendy. Secondly, whether the fashion products have a famous brand name or not has a significant influence on browsing behavior for stores and fashion trends information search. Thirdly, time constraint is found to influence significantly on respondents' browsing for promotions information search. Lastly, occasion for product worn shows a significant influence on browsing behavior for stores and fashion trends information search. The managerial implications are provided based on findings.