• 대한기계학회논문집A
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• 제21권1호
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• pp.32-44
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• 1997

A moving sliding surface(MSS) was proposed earlier for the second-order variable structure control system(VSCS). The MSS was disigned to pass arbitrary initial conditions, and subsequently moved towards a predetermined sliding surface by rotating and/or shifting. This methodology led to fast and robust control responses of the second-order VSCS, especially in a reaching phase. However, the moving algorithm of the MSS was too complicated to be employed to the high-order VSCS. To resolve this problem, a new moving algorithm based on the fuzzy theory is proposed in this paper. For the generalization of the MSS, the conditions for rotating or shifting are firstly investigated. Then the fuzzy algorithm is formulated by adopting the values of the surface function and the total discontinuity gain as input variables, and the variation of the surface function as output variable. The position control problem of an electrohydraulic servomechanism is adopted in order to demonstrate the efficiency and the feasibility of the proposed MSS associated with fuzzy algorithm.

• Journal of Computing Science and Engineering
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• 제8권2호
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• pp.94-106
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• 2014

Schema matching is widely used in many applications, such as data integration, ontology merging, data warehouse and dataspaces. In this paper, we propose a novel matching technique that is based on the order of attributes appearing in the schema structure of query results. The appearance order embodies the extent of the importance of an attribute for the user examining the query results. The core idea of our approach is to collect statistics about the appearance order of attributes from the query logs, to find correspondences between attributes in the schemas to be matched. As a first step, we employ a matrix to structure the statistics around the appearance order of attributes. Then, two scoring functions are considered to measure the similarity of the collected statistics. Finally, a traditional algorithm is employed to find the mapping with the highest score. Furthermore, our approach can be seen as a complementary member to the family of the existing matchers, and can also be combined with them to obtain more accurate results. We validate our approach with an experimental study, the results of which demonstrate that our approach is effective, and has good performance.

• 소음진동
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• 제6권5호
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• pp.575-585
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• 1996

In order to build a quiet and comfortable ship, the noise levels on board ship must be predicted at early design stage. Statistical Energy Analysis (SEA) developed by R. H. Lyon has been well known to be the most useful frame work to study the energy flow of noise and vibration in structure. This paper applied this theory to predict the transmission loss of structure-borne noise of model structure and has developed computer program. Components constructions model structure have been all considered as SEA elements. And we also estimated the SEA parameters from the model structure. Using SEA and a new conception of STL, we found the transimission character of structure-borne noise theoretically by the idealized ship model, and then compared the results with three cases.

• Structural Engineering and Mechanics
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• 제37권6호
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• pp.617-632
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• 2011

A concept of crash energy absorbing (CEA) lattice structure for an inflatable morphing vehicle body (Lee et al. 2008) has been investigated as a method of providing rigidity and energy absorption capability during a vehicular collision (Lee et al. 2007). A modified analytical model for the CEA lattice structure design is described in this paper. The modification of the analytic model was made with a stiffness approach for the elastic region and updated plastic limit analysis with a pure plastic bending deformation concept and amended elongation factors for the plastic region. The proposed CEA structure is composed of a morphing lattice structure with movable thin-walled members for morphing purposes, members that will be locked in designated positions either before or during the crash. What will be described here is how to model the CEA structure analytically based on the energy absorbed by the CEA structure.

• 한국항만학회지
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• 제13권2호
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• pp.365-380
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• 1999

In this thesis the legal systems related to real estate and sea area utilization are studied in order to improve them for construction of Very Large Floating Structure. Main research subjects are as follows: 1) Whether can Very Large Floating Structure be accepted or not as real estate like house and land\ulcorner 2) How can the sea area which is occupied by Very Large Floating Structure be utilized\ulcorner As the conclusion, the Very Large Floating Structure can be registered as real estate even though it is not specified by Korean law for the present. The design concept of Very Large Floating Structure can be interpreted as satisfying enough necessary conditions and factors for Very Large Floating Structure to become real estate. In the near future, we have to make improvement on the laws related with the construction of Very Large Floating Structures so that private sectors can joint the construction. In additions, a new law for various floating structures should be made as soon as possible.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권8호
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• pp.371-377
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• 2005

This paper Presents the Potential gradient characteristics of structure grounding electrode when a test current flows through grounding electrode. In order to analyze the potential gradient of ground surface on structure grounding electrode, the reduced scale model has been used. The potential gradient has been measured and analyzed for types of structure using the hemispherical grounding simulation system in real time. The structures were designed through reducing real buildings and fabricated with four types on a scale of one-one hundred sixty. The supporter was made to put up with weight of structure and could move into vertical, horizontal, rotary direction. When a test current flowed through structure grounding electrodes, ground potential rise was the lowest value at electric cage type(type B). According to resistivity and absorption percentage In concrete attached to structure, the potential distribution of ground surface appeared differently.

• 산업경영시스템학회지
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• 제18권36호
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• pp.365-370
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• 1995

In recent years, there have been attempts to explain firms' capital structure based upon the agency theory which considers agency problems arising due to ownership structure. Agency theory starts from the coctractual relationship (explicit or implicit) between principals and agents. Since uncertainty exists in real world and information is distributed asymmetrically, there are conflicts between principals and agents. The objectives of this study are to analyze, based upon agency theory, factors which are expected to affect firms' capital structure and to test empirically the relevance of agency cost hypothesis about the determination of capital structure, For these purposes, this paper carried out multiple regression in order to examine whether the factors of agency costs affect significantly the determination of capital structure. The results of empirical analysis are summarrized as follows; First, insider-equity ration has been negatively correlated with capital structure. Second, growth opportunity variabless has been insignificant coefficients with capital structure.

• 정보관리학회지
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• 제35권3호
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• pp.101-121
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• 2018

본 연구는 연구논문의 논리적 의미 구조 메타데이터 항목에 해당하는 데이터에 담겨 있는 문장의 구성에 따라 시스템에서 적절한 항목으로 자동 식별 처리될 수 있도록 하는, 문장의미론(Sentence Semantics)적 분석 방법을 제안하고자 하는 목적으로 수행되었으며, 의미 구조 메타데이터 항목 중 'Research Objectives'와 'Research Outcomes'에 해당하는 연구 논문 문장의 구조를 어절 수, 접속어 종류, 다수 출현한 단어들의 문장 내 역할, 문장에서 다수 출현한 어미 형태 등을 기준으로 분석해 정리하였다. 연구 결과, 문장들의 어절 수는 'Research Objectives'는 평균 38개, 'Research Outcomes'는 평균 212개로 나타났으며, 접속어의 경우 'Research Objectives'는 인과-순접-대등-환언/요약 관계를 나타내는 접속어 순으로, 'Research Outcomes'는 인과-대등-순접-환언/요약 관계를 나타내는 접속어 순으로 많이 출현한 것으로 파악되었다. 출현빈도가 높은 분석 대상 단어들은 각각 문장 내에서 주어, 목적어, 서술어 역할 등으로 사용되고 있었으며, '역할'이나 '요인', '관계'는 목적이나 결과 부분 모두에서 비슷한 역할을 담당하고 있었지만 '연구'는 같은 단어라도 연구의 목적 부분과 결과 부분에서 사용되는 역할에 차이를 보였다. 마지막으로 문장 내 동사의 어미는 'Research Objectives'에서 '~고자'와 '~였다', 'Research Outcomes'에서 '~었다', '~있다', '~였다'가 많이 출현하였다. 본 연구는 연구자의 학술적 이해형성을 지원하기 위해 연구논문이 담고 있는 공통된 논리적 의미를 반영한 메타데이터 요소의 자동 식별과 입력 방안을 제시하는 데 활용할 수 있는 기초 연구로서 의의가 있다.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2009년도 학술대회
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• pp.1279-1286
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• 2009

"Interactivity refers to the possibility of an audience actively participating in the control of an artwork or representation." Andy Cameron, Dissimulations Interaction can be described as a way or function that improves the participation of audiences/viewers to being immersed into the medium itself. Until now, however, in terms of interactive cinema, interaction has not shown a sufficient participation for audiences. Specifically, audiences/viewers described that the structure of storytelling has failed to satisfy their requirements, in order to participate in the structure of storytelling. The aim of the research itself, therefore, began to ask and wonder why audiences/viewers criticised the participation which audiences/viewers are able to control storytelling, in interactive cinema, could not satisfied them in order to control and follow a storyline of interaction. In general idea, in interactive cinema, the function which allows audiences/viewers to be immersed into the storylines, must allow the immediacies of interaction. Audiences/viewers must therefore be able to satisfy the general idea of interactive cinema through controlling the directions of every choice offered. They must also be able to be immersed in the interactive storylines. Which of the prime causes can be improved or re-considered, to satisfy the participation requirements of audiences/viewers? The intention of this research also began to investigate a suitable method of storytelling within a narrative structure of interactive medium (interactive cinema). Through questioning the matter (it will be described in a later chapter), this research will be focused on the relationship between narrative structured interaction and audiences/viewers, which is of prime importance in relation to interaction. To further the research, Pilot study (experiment with the basic interactive narrative structure) was offered in order to understand and maintain a suitable method of storytelling within a narrative structure of interactive cinema and it also was explored to understand how the aim of the research would be maintained for further qualitative research.

• 한국해안·해양공학회논문집
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• 제26권1호
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• pp.33-40
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• 2014

극한 해양 환경하중을 고려한 해상풍력터빈 지지구조물에 대한 신뢰성 해석을 수행하였다. 신뢰성 해석을 위한 한계상태함수는 mud-line에서 지지구조물의 동적응답으로 정의되며, 동적응답은 정적응답과 동적응답계수의 곱으로 정의된다. 동적응답계수는 설계조건에서의 동적 시간이력응답을 분석하여 구할 수 있다. 허브(Hub) 위치에 작용하는 추력은 GH_Bladed를 사용하여 계산하였으며, 정적하중으로 적용하였다. 동적응답계수는 대수정규분포, 지반물성 중 내부마찰각은 상한과 하한이 결정된 베타분포이며, 그 외 설계변수는 정규분포 확률변수로 취급되었다. mud-line 에서의 동적응답을 통해 정의된 한계상태함수에 따라 일계신뢰도법(First order reliability method, FORM)을 사용하여 해상풍력터빈 지지구조물의 신뢰도지수를 산정하였다.