• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.510-513
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• 1996

This paper consists of the speed sensorless vector control of induction motors with the estimation of rotor resistance. In the application of variable-speed induction motor drives, if an inaccurate rotor resistance is used because the rotor resistance can change due to skin effects and temperature variables, it is difficult to achieve a collect field orientation. In this paper, to overcome these difficulties adaptive algorithm is designed for rotor resistance identification at the beginning of the transient state. And an adaptive flux observer is used for the purpose of estimating rotor flux and speed in the speed sensorless scheme. Computer simulations are carried out to verity the validity of the proposed algorithm.

• Korean Journal of Child Studies
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• v.34 no.1
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• pp.1-20
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• 2013

This study examined the emergent literacy development of children and the effects of the home literacy environment on it. 861 pairs each-consisting of a mother and a child aged from three to six years old were asked to complete the early literacy parent questionnaire (Boudreau, 2005) and the home literacy environment questionnaire (Park & Kim, 2008). The results showed that : (1) girls achieved higher scores than boys in emergent literacy and its subcategories. (2) there were age differences in all of the subcategories of emergent literacy except the categories of 'orientation toward literacy' and 'phonological awareness'. (3) The study revealed that 'reading books' in the home literacy environment was the most contributive variable in predicting emergent literacy after controlling the age and gender followed by 'literacy learning'

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.308-311
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• 2004

Nowadays, plastic industry has needed to produce parts that require high precision and quality. To make a high precision and quality part, before injection molding, plastic material is investigated about their properties such as shrinkage, warpage, etc. In this study, experiments were conducted with PA6(polyamid) to figure out shrinkage behavior according to three type aspect ratio of samples. The injection speed that affects on shear rate, molecular orientation within plastic part was determined as main variable of experiment. As a result of experimental study, part shrinkage had a tendency to be decreased by increasing injection speed and aspect ratio of samples.

• Journal of Information Technology Services
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• v.4 no.1
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• pp.71-105
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• 2005

The purpose of this study was to test various variables that affect CRM performance in order to evaluate CRM performance. The results of the proposed research hypotheses are as follows; First, the IS based factors perform more important roles on system and information quality compared to organizational factors. Second, the variables of IS and planning capability playa role as a parameter. Third, among organizational factors, non-structural factors such as degrees of acceptance of business transition, support of CEO, and customer-orientation perform more important roles on CRM. Fourth, IS based factors have bigger Impact on information quality than system quality. Fifth, it was proven that IS quality, proposed as a parameter and as a dependant variable, and CRM have significant relations.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.703-706
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• 2002

Piezoelectric thin film such as ZnO and AlN can be applicable to FBAR (Film Bulk Acoustic Resonator) device of thin film type and FBAR can be applicable to MMIC. The characteristic of FBAR device is variable according to the deposition conditions of piezoelectric thin film when preparation of thin film by sputtering method. In this study, we prepared ZnO thin film for FBAR using Facing Targets Sputtering apparatus which can be deposited fine Quality thin film because temperature increase of substrate due to the bombardment of high-energy particles can be restrained. And crystalline and c-axis preferred orientation of ZnO thin film with deposition conditions was investigated by XRD.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 1995.10a
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• pp.77-83
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• 1995

This study explores the patterns of housing-related attitudes and the kind of needs for shared community spaces among small-sized apartment housing dwellers. The major findings are as follows. The majority of the dwellers are in strong need of common spaces, especially for children's activities, Social gathering and physical exercises. Housing-related attitudes are found and grouped into 4categories the propensity to making up common society, the propensity to pursuing the quality of neighborhood, the propensity to orienting natural environment, and the propensity to participating in community. The intensity of the needs depends on family lifecycle, employment status of housewives, and the size of floor space. The propensity to making up common society and pursing the quality of neighborhood have stronger impact on needs of shared community space. This study reveals that the sense of community orientation is the most powerful predictor variable for shared community space needs .

• Proceedings of the KIEE Conference
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• 1989.11a
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• pp.65-67
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• 1989

To study hopping conducting mechanism in PAN(polyacrylonitrile) carbon fiber, the temperature and frequency dependence of electrical conductivity and magnetoresistance characteristics were investigated. Electrical conductivity in the range of $60^{\circ}K-300^{\circ}K$ show VRH(variable range hopping) properties which introduced by Mott's theory, and also such properties can be explained by the frequency dependence of electrical conductivity below $5{\times}10^6$ Hz. The negative magnetoresistance observed below 35KG magnetic field, and the properties difference between M40 and T300 with increasing magnetic field is supposed due to on effect connected with crystalline state and orientation of structure.

• Journal of the Korean Home Economics Association
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• v.33 no.4
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• pp.199-212
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• 1995

The purpose of this study were (1) to find out if socio-demographic, resource, psychological, and socio-environmental variables have significant effect6s on environmentally concious consumer behavior and (2) to examine the independent influences of variables related to the environmentally concious behavior. the subjects were 384 housewives living in Kwangju. the data were collected by questionnare methods and analyzed through SPSS PC+ program. The findings were as follows : Environmentally concious behavior differed significantly according to family income, employment, attending a consumer education experience, knowledge about environmental conservation method, post-industrial consumer value orientation, awareness of the seriousness of environmental problems, feeling of efficacy about helping to solve environmental problems, perception of time limit, influence of reference group and the degree of interesting in environmental information. The most critical variable was influence of reference group, that is, environmentally concious behavior by friends and neighbors.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.5
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• pp.1640-1648
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• 1991

본 연구에서는 이러한 편사 함수 최소화의 방법을 적용함에 있어 보다 안정된 수렴성과 계산 시간을 단축시키기 위하여 근접 위치 방법(near position method)을 개 발하여 적용하였다. 근접 위치 방법이란 이론적 해석법으로 풀기가 불가능한 기구학 을 갖는 6관절 로봇을 반복적 해석법을 사용한다는 것을 전제로 하여, 초기 위치를 목 표 위치에 가능한 근접하게 잡아서 반복 계산을 수행하는 방법으로써 로봇의 기구학적 자세에 따른 수렴의 불안정성을 방지하고, 계산 시간을 단축하는데 그 목적이 있다.

• Journal of the Korean housing association
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• v.8 no.3
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• pp.91-98
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• 1997

This study explores the patterns of housing-related attitudes and the kind of needs for shared community spaces among small-sized apartment housing dwellers. The major findings are as follows. The majority of the dwellers are in a strong need of common spaces. especially for children's activities. social gathering and physical exercises. Housing consciousness can be grouped into 4 categories the propensity to making up common society. the propensity to pursuing the quality of neighborhood. the propensity to orienting natural environment. and the propensity to participating in community. Families with children in primary school are more likely to get involved in the community and the common society than those with children in high school or those in the stage of launching a family. The propensity to making up common society and pursing the quality of neighborhood have stronger impact on needs for shared community space. This study reveals that the sense of community orientation is the most powerful predictor variable for shared community space needs.