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A Study on Information Search and Fashion Involvement as related to the Degree of Adolescent Delinquency (청소년의 비행정도와 정보탐색 및 유행몰입과의 관계연구)

  • 이은실;이명희
    • Journal of the Korean Society of Clothing and Textiles
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    • v.23 no.3
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    • pp.402-413
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    • 1999
  • The objectives of this study were to investigate the relationships among the degree of delinquency and clothing buying behavior information search and fashion involvement and to examine the causal relationships of adolescent delinquency demographic variables and fashion involvement on information search. Subjects for this study were 537 high school students(male ; 225, female : 312) in Seoul Korea. the results of the study were as follow. 1. Four factors of adolescent's delinquency derived by factor analysis : F. 1 'general position delinquency' F. 2 'school-norm delinquency' F3. 'personal delinquency' : F.4 'sexual delinquency'. 2. There were partially significant correlations between the degree of adolescent's delinquency and information search and fashion involvement. There were significant relationships between degree of delinquency and degree of clothing purchasing frequency. companion while shopping and source of clothing expenses. 3. In the case of male students fashion involvement and sexual delinquency had a direct effect on information search(R2 =.278) General position delinquency and allowance had a indirect effect on information search through Father's level of education had a direct effect on allowance. the present findings provide that in general the more allowance students received the higher the general position delinquency for both males and females, The higher the general position delinquency the higher the degree of fashion involvement and information search. Therefore it can be concluded that relatively mild delinquency acts such as drinking. smoking and going to discothque have more influence on fashion involvement and information search that serious delinquency acts such as violence and robbery.

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A Study on the Efficient Optimization Method by Coupling Genetic Algorithm and Direct Search Method (유전적 알고리즘과 직접탐색법의 결합에 의한 효율적인 최적화방법에 관한 연구)

  • D.K. Lee;S.J. Jeong;S.Y. Kim
    • Journal of the Society of Naval Architects of Korea
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    • v.31 no.3
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    • pp.12-18
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    • 1994
  • Optimization in the engineering design is to select the best of many possible design alternatives in a complex design space. In order to optimize, various optimization methods have been used. One major problem of traditional optimization methods is that they often result in local optima. Recently genetic algorithm based on the mechanics of natural selection and natural genetics is used in many application fields for optimization. Genetic algorithm is more powerful to local optima, but it requires more calculation time and has difficulties in finding exact optimum point in design variable with real data type generally. In this paper. hybrid method was developed by coupling genetic algorithm and traditional direct search method. The developed method finds out a region for global optimum using genetic algorithm, and is to search global optimum using direct search method based on results obtained from genetic algorithm. By using hybrid method, calculation time is reduced and search efficient for optimum point is increased.

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Improvement of Dynamic encoding algorithm with history information (동부호화 최적화 기법의 성능개선을 위한 과거 검색정보의 활용)

  • Park, Young-Su;Kim, Jong-Wook;Kim, Yeon-Tak
    • Proceedings of the KIEE Conference
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    • 2006.04a
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    • pp.111-113
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    • 2006
  • DEAS is an direct searching and optimization method that based on the binary code space. It can be classified as an direct hill climbing searching. However, because of binary code space based searching, the searching in low resolution has random property. As the resolution of code increases during the search, its property of searching changes like that of hill climbing search. This paper propose a method for improving the performance of minimum seeking ability of DEAS with history information. The cost evaluation is increased. However the minimum searching ability of DEAS is improved along the same starting resolution.

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An Investigation of the Mount Design of Engine Power System in Vehicles (차량 엔진동력계의 마운트 설계에 관한 연구)

  • 박노길
    • Transactions of the Korean Society of Automotive Engineers
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    • v.4 no.1
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    • pp.36-54
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    • 1996
  • This paper presents a design procedure of engine power system for vehicle. The implementation and operation environment of engine plant is somewhat diversed through the various kind of vehicles. Regarding this point, we adopt a multi-purposed design objective function which can be easily modified to reflect diverse mount design rules which have been recommended and used generally by relating fields. To search the mount parameters which provide the optimal performance, a direct search method based on an orthogonal array is developed and applied. Through several simulated results, the effectiveness of the developed disign tool is investigated and discussed.

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Optimal Design of Interior PM Synchronous Machines Using Randomly-Guided Mesh Adaptive Direct Search Algorithms (RG-MADS를 적용한 매입형 영구자석 동기전동기의 최적설계)

  • Kim, Kwang-Duck;Lee, Dong-Su;Jung, Sang-Yong;Kim, Jong-Wook;Lee, Cheol-Gyun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.61 no.2
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    • pp.216-222
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    • 2012
  • Newly proposed RG-MADS (Randomly Guided Mesh Adaptive Direct Search) has been applied to the optimal design of Interior Permanent Magnet Synchronous Motor (IPMSM) which has the distinctive features of magnetic saturation. RG-MADS, advanced from classical MADS algorithm, has the superiority in computational time and reliable convergence accuracy to the optimal solution, thus it is appropriate to the optimal design of IPMSM coupled with time-consuming Finite Element Analysis (FEA), necessary to the nonlinear magnetic application for better accuracy. Effectiveness of RG-MADS has been verified through the well-known benchmark-functions beforehand. In addition, the proposed RG-MADS has been applied to the optimal design of IPMSM aiming at maximizing the Maximum Torque Per Ampere (MTPA), which is regarded as representative design goal of IPMSM.

Controller Parameters Design of Direct Drive Servo Valve Using Genetic Algorithm and Complex Method (유전자 알고리즘과 콤플렉스법에 의한 직접구동형 서보밸브의 제어기 상수값 설계)

  • Lee, Seong Rae
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.37 no.4
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    • pp.475-481
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    • 2013
  • The control system of a direct drive servo valve is a nonlinear system, and the flow force effect on the spool motion is significant and dependent on the load pressure. To satisfy the control system design requirements, the optimal parameters of the lead-lag controller and the derivative feedback controller are searched for using a genetic algorithm and a complex constrained direct search type method. The obtained controller parameters successfully perform their role to satisfy the control system design requirements.

Determinants of the Consumer's Search for Information -Focusing on durables Goods Purchases by American Consumers- (소비자 정보탐색의 결정요인-미국소비자들의 내구재구매행동을 중심으로-)

  • 여정성
    • Journal of Families and Better Life
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    • v.7 no.1
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    • pp.15-25
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    • 1989
  • The purpose of this study is to examine the factors affecting the consumer's search for information and the relationship between the amount of search and the final price paid. The model indicates the demand for search is affected by the market price of each durable good purchased, the tim available for search, family income, direct cost of search, the initial stock of information, effectiveness of search, and shopping attitudes. The final price savings are a function of search, price of dispersion in the market, the initial stock of information, and effectiveness of search. Data from the Pane Study on Consumer Decisions and Asset Management were used for the empirical testing of the theoretical model. The amount of information search as dependent variable is represented by two different measures, the level of discussion with others and the number of stores visited. The amount of discussion with others depends mainly on the respondent's shopping attitude. The higher the wife's desire to search, the higher the degree of husband's comparison shopping, the less the husband's perception of price-quality relationship, the higher the level of discussions with others. The number of stores visited depends on the average market price of product purchased and the level of family income. The higher the average market price and he higher the level of family income, the greater the number of stores visited. The final savings depend upon the level of information search. The greater the number of store visited, but the less the purchase is discussed with stores, the higher the final savings are.

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Optimization Method for the Design of LCD Back-Light Unit (LCD Back-Light Unit 설계를 위한 최적화 기법)

  • Seo Heekyung;Ryu Yangseon;Choi Joonsoo;Hahn Kwang-Soo;Kim Seongcheol
    • Journal of KIISE:Computer Systems and Theory
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    • v.32 no.3
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    • pp.133-147
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    • 2005
  • Various types of ray-tracing methods are used to predict the quantity measures of radiation illumination, the uniformity of illumination, radiation performance of LCD BLU(Hack-Light Unit). The uniformity of radiation illumination is one of the most important design factor of BLU and is usually controlled by the diffusive-ink pattern printed on the bottom of light-guide panel of BLU. Therefore it is desirable to produce an improved (ideally, the optimal) ink pattern to achieve the best uniformity of radiation illumination. In this paper, we applied the Welder-Mead simplex-search method among various direct search method to compute the optimal ink pattern. Direct search methods are widely used to optimize the functions which are often highly nonlinear, unpredictably discontinuous, and nondifferentiable, The ink-pattern controlling the uniformity of radiation illumination is one type of these functions. In this paper, we found that simplex search methods are well suited to computing the optimal diffusive-ink pattern. In extensive numerical testing, we have found the simplex search method to be reasonably efficient and reliable at computing the optimal diffusive-ink pattern. The result also suggests that optimization can improve the functionality of simulation tools which are used to design LCD BLU.

A Study on the Structural Equation Modeling of the Relationships among Major Satisfaction, Career Search Efficacy, and Career Exploration Behavior with Marine Science High School Students (수산해양계열 고등학생의 전공만족, 진로탐색 자기효능감 및 진로탐색행동의 구조적 관계 연구)

  • Heo, Gyun
    • Journal of Fisheries and Marine Sciences Education
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    • v.25 no.6
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    • pp.1306-1314
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    • 2013
  • The purpose of this study is to find the structural relationships among major satisfaction, career search efficacy, and career exploration behavior with marine science high school students. For investigating this topic, 524 students were surveyed from the marine science high schools. In order to find out the structural relationships among major satisfaction, career search efficacy, and career exploration behavior, structural equation modeling was used. Followings were the results of the research: (a) Major satisfaction effected significantly on the career search efficacy. (b) Career search efficacy effected significantly on the career exploration behavior. (C) There was not significant direct cause and effects from major satisfaction to career exploration behavior, but indirect effect was significant. Some recommendations were suggested for increasing career exploration behavior of marine science high school students.

Current Update on Transcranial Direct Current Stimulation as Treatment for Major Depressive Disorder (주요우울장애의 치료로서 경두개 직류자극술(Transcranial Direct Current Stimulation)의 현재)

  • Lee, Seung-Hoon;Kim, Yong-Ku
    • Korean Journal of Biological Psychiatry
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    • v.25 no.4
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    • pp.89-100
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    • 2018
  • Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation method that delivers 1-2 mA of current to the scalp. Several clinical studies have been conducted to confirm the therapeutic effect of major depressive disorder (MDD) patients with tDCS. Some studies have shown tDCS's antidepressant effect, while the others showed conflicting results in antidepressant effects. Our aim of this review is to understand the biological bases of tDCS's antidepressant effect and review the results of studies on tDCS's antidepressant effect. For the review and search process of MDD treatment using tDCS, the US National Library of Medicine search engine PubMed was used. In this review, we discuss the biological mechanism of tDCS's antidepressant effect and the existing published literature including meta-analysis, systematic review, control trial, open studies, and case reports of antidepressant effects and cognitive function improvement in patients with MDD are reviewed. We also discuss the appropriate tDCS protocol for MDD patients, factors predictive of response to tDCS treatment, the disadvantages of tDCS in MDD treatment, and side effects.

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