• Journal of Advanced Marine Engineering and Technology
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• v.33 no.8
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• pp.1203-1211
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• 2009

The dynamics of underwater vehicles can be greatly influenced by the dynamics of the vehicle thrusters. The control of the state of the hovering or very slow motion of the underwater vehicle is most important for automatic docking or control of the manipulator of the vehicle. The dynamics of the thruster based on the electric motor is nonlinear and has uncertain parameters. Since the dynamics of the vehicle coupled with the dynamics of the thruster is nonlinear and has uncertain parameters, a robust control is very effective for a desired motion tracking of the uncertain and nonlinear vehicle. In this paper a study was performed on the robust control scheme of the very slow motion or hovering motion of the underwater vehicle actuated by the electric motor. Also, a concurrent control on the state of the vehicle with nonlinearity and uncertain parameters was performed. A sliding mode control algorithm out of robust controllers was designed and applied, which compensates the nonlinear forces and uncertain parameters of the vehicle and actuator. Through a computer simulation, the proposed control scheme was compared with a linear PD controller and its superior performance was validated.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.6
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• pp.89-98
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• 2015

The purpose of this study was to investigate the effect of the Government's entrepreneurial support policy(educational support, financial support and marketing support) on entrepreneurship and entrepreneurial intention. This study examined educational support, fund support and marketing support as the The Government's entrepreneurial support polity variables and innovativeness, progressiveness and risk-taking as entrepreneurship variables. The sample of this study was composed of 331 existing and potential entrepreneurs selected from the national panel of a online web survey research firm. Data were collected using self-administerd structured questionnaires and analyzed employing structural equation modelling techniques. This study found that three entrepreneurship variables(innovativeness, progressiveness and risk-taking) had positive direct effects on entrepreneurial intention and that three Government's entrepreneurial support policy variables (educational support, financial support and marketing support) had positive direct effects on entrepreneurship, whereas these three variables had positive indirect effects on entrepreneurial intention. The theoretical and practical implications of the findings were discussed and the directions for future research were suggested.

• School Mathematics
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• v.16 no.1
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• pp.19-37
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• 2014

This study investigated the degree of understanding pre-service teachers' random variable concept, based on the attention and the importance for developing pre-service teachers' ability on statistical reasoning in statistics education. To accomplish this, the subject of this study was 70 pre-service teachers belonged to three universities respectively. The teachers were given to 7 tasks on random variable and requested to solve them in 40 minutes. The tasks consisted of three contents in large; 1) one was on the definition of random variables, 2) the other was on the understanding of random variables in different/diverse conditions, and 3) another was on problem solving relevant to random variable concept. The findings are as follows. First, while 20% of pre-service teachers understood the definition of random variable correctly, most teachers could not distinguish between random variable and variable or probability. Second, there was a significant difference in understanding random variables in different/diverse conditions. Namely, the degree of understanding on the continuous random variable was superior to that of discrete random variable and also the degree of understanding on the equal distribution was superior to that of unequality distribution. Third, three types of problems relevant to random variable concept dealt with in this study were finding a sample space and an elementary event, and finding a probability value. In result, the teachers responded to the problem on finding a probability value most correctly and on the contrary to this, they had the mot difficulty in solving the problem on finding a sample space.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2011.04a
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• pp.665-668
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• 2011

철근콘크리트 구조물은 타설 후 시간이 경과함에 따라 물리적인 요인과 화학적인 요인으로 인하여 열화가 발생한다. 열화를 고려한 구조해석에서 모든 열화 관련 변수를 고려하는 것은 비효율적이다. 따라서 구조물의 거동과 밀접한 관련이 있는 중요열화변수를 정의하는 것이 필요하다. 본 연구에서는 철근콘크리트 전단벽의 경년열화 해석시 중요변수를 고려하기 위하여 민감도해석을 수행하였다. 해석결과에 의하면 재료의 경화와 관련한 변수들이 열화와 관련한 변수들보다 지진응답이 민감하게 나타났다. 해석모델의 낮은 철근비로 인하여 콘크리트의 탈락에 의한 지진응답의 변화보다 철근의 단면손실에 의한 지진응답의 변화가 크게 나타났다. 만약 원전과 같이 철근비가 높은 전단벽에서는 철근의 단면손실도 지진응답에 대한 중요변수가 될 수 있을 것으로 사료된다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.11C
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• pp.1073-1078
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• 2007

In this paper, we propose an iterative mixed norm image restoration algorithm using multi regularization parameters. A functional which combines the regularized $l_2$ norm functional and the regularized $l_4$ norm functional is proposed to efficiently remove arbitrary noise. The smoothness of each functional is determined by the regularization parameters. Also, a regularization parameter is used to determine the relative importance between the regularized $l_2$ norm functional and the regularized $l_4$ norm functional using kurtosis. An iterative algorithm is utilized for obtaining a solution and its convergence is analyzed. Experimental results demonstrate the capability of the proposed algorithm.

• 한국벤처창업학회:학술대회논문집
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• 2016.04a
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• pp.177-179
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• 2016

본 연구의 목적은 우리나라도 초 고령화시대가 도래 하고 있다. 80세의 평균수명이 100세 까지 늘어나면서 인생을 바라보는 관점이 달라지고 있다. 평생직장이 아닌 평생 직업으로 바뀌면서 정년 후 무엇을 하며 어떻게 살아갈 것인가. 경찰관 역시 후반전 인생설계를 하지 않을 수가 없다. 그러나 실상은 격무에 시달리고 퇴직 준비를 제대로 못하며 임무가 산적된 경우가 경찰관의 다반사가 현 실태이다. 그러면 이와 관련된 창업의 전 단계를 알아보자"퇴직예정 경찰관에게 심리적 특성요소들이 창업의지에 미치는 영향"과 -경력지향성의 조절효과 중심으로, 이에 부합되도록 예비창업가의 심리적 특성요인에 변수 요소를 찾아보면 사회적지향성, 성취욕구, 위험감수성, 자기 효능감, 창의성의 5가지 독립요소로 정리하고 창업의지를 종속 변수로 하여서 이들 간에 어떠한 영향을 미치는지 여부를 확인하고 마찬가지로 예비창업자 경력과 창업의지와 관계를 알아보며 경력지향성에 포함되는 요소들 관리, 사업, 안정, 기술, 자율지향성은 퇴직경찰관의 심리적 특성요인과 창업의지에 조절변수 요소들로 상관관계들을 검토해보기 위해서 연구모형과 가설을 세워본다. 또한 이를 위하여 검증단계로 현직경찰관 154명에 대한 설문지를 발송하였으며 접수가 완료되면 검증을 실시하기 위해 통계분석 처리를 할 예정이다. 첫째. 예비창업자의 개인적 특성으로 구성하는 요소들은 사회적지향성, 성취욕구, 위험감수성, 자기 유능감 창의성은 창업의지와 (+)정의 관계로 창업의지에 영향이 미칠 것이다. 둘째. 예비창업자의 경력이 창업의지와 (+)정의 관계로 창업의지에 영향이 미칠 것이다. 셋째. 예비창업자 경력 지향성에는 관리지향성 사업지향성 자율지향성 기술지향성 안정지향성은 심리적 특성과 창업의지에 조절효과로 정(+)의 관계로 영향을 미칠 것이다.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.05a
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• pp.345-350
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• 2003

현대의 많은 제조산업에서 제품 모델의 다양성은 점점 증가하고 있다. 제품 모델을 관리하기 위한 이론적 모델이 존재하지만, 현실의 변수들을 이론적으로 다루기 쉽지 않으며, 수리적인 접근도 한계가 있다. 본 논문은 생산재고 정책을 적용하기 위하여 다수의 제품 모델을 군집화 하기 위한 실증연구를 목표로 한다. 수요 분포, 생산 특성, 재고 수준의 세 가지 측면에서 각 모델의 공급에 영향을 미칠 수 있는 몇 가지 변수들을 정의하였다. 먼저 변수들의 상호 연관관계를 파악하기 위해서 요인 분석을 수행하여 변수들의 주요 유형을 파악하고, 이를 실제 생산 데이터에 적용함으로써 실증적 분석을 하였다. 본 논문에서 는 자동차 속기 모델에 위의 변수들을 적용하여 모델의 군집화를 수행하였다. 이러한 제품 모델 관리에 관한 연구는 다단계 공급망의 형성과 민첩한 생산정책 수립의 요구와 함께 중요한 의미를 가질 것이다.

• Management & Information Systems Review
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• v.35 no.1
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• pp.1-22
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• 2016

The increased number of foreigners in Korea (now more than 1.8 million) has necessitated understanding, analyzing and interpreting the immigration issues in order to solve the foreign workers' social problems. Foreign workers in Korea are suffering from a lot of difficulties such as bad working conditions, lower income, unpaid wages, cultural adaptation, etc. This paper aims to investigate how the social capital factors (social network and social support) and media use (Korean and Chinese media) influence cultural adaptation and job satisfaction. In addition, the paper aims to provide practical guidelines for social welfare organizations and enterprises which support and recruit them. The sample of our respondents was 273 Chinese workers (216 Korean-Chinese workers and 57 Han-Chinese workers) in Korea. We used SPSS 21.0 for statistical analysis. The results are as follows: Korean network, native network, family support, native support and Korean media use have a significant effect on cultural adaptation. Korean network, native network, family support, native support and Korean media use have a significant impact on job satisfaction. Furthermore, cultural adaptation was found to mediate the relationship between Korean/native network and job satisfaction as well as between family/native support and job satisfaction. Cultural adaptation was also found to mediate the relationship between Korean media use and job satisfaction.

• Proceedings of the Costume Culture Conference
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• 2004.04a
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• pp.127-129
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• 2004

일찍이 제품흥미나 중요성 대신 관여(involvement)의 개념이 소개된 이래로 마케팅과 소비자 행동 분야뿐 아니라 의류학분야의 여러 연구에서 관여는 구매자의 행동을 이해하는데 중요한 변수로 이해되어왔다. 그러나 관여의 개념은 의류제품의 특수성으로 인하여 변인이 조작적으로 정의되는 과정에서 의복관여, 유행관여, 패션관여 등의 용어가 혼용되어 왔다. 이러한 경향은 선행연구와 후행 연구의 연계성이라는 측면에서 “의복관여”라는 변수를 도입한 연구들의 해석에 많은 어려움을 주어 왔다. (중략)

• The Journal of the Korea Contents Association
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• v.7 no.6
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• pp.52-59
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• 2007

This paper presents a greedy method for user-steered mesh segmentation, which is based on the merging priority metric defined for representing the geometric properties of meaningful parts. The priority metric is a weighted function composed of five geometric parameters: distribution of Gaussian map, boundary path concavity, boundary path length, cardinality, and segmentation resolution. This scheme can be extended without any modification only by defining more geometric parameters and adding them. Our experimental results show that the shapes of segmented parts can be controlled by setting up the weight values of geometric parameters.