• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 26-27 Oct. 1990
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• pp.878-883
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• 1990

There have been many approaches to solve the disturbance rejection problem in the control of LTI systems with state independent disturbances or possibly nonlinear state dependent disturbances. From the view point of each actuator, robot manipulators can be modeled as the second class of systems. With this model, M.Nakao et al. [1] introduced a decentralized control scheme based on interference estimation which is simple in its implementation and robust to the coupled dynamics and parameter variations. This paper systematically generalizes the control scheme to arbitrary finite dimensional LTI systems with disturbances. In doing so, we develop a disturbance observer theory for solving the disturbance rejection problem. We also present a discrete version of the theory with discussion of sampling and time-delay effects.

• 대한기계학회논문집A
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• 제24권1호
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• pp.182-189
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• 2000

This paper presents the real time control method of 5-axis NC machine for high precision and productivity based on the curvature theory, of a ruled surface. The trajectory, of NC machine is described by, way of a ruled surface generated by the points on part surface and tool axis direction vector. The curvature theory, of a ruled surface is then applied to deter-mine the motion parameters of the 5-axis machine for control. The controller computes position, orientation, and differential motion parameters of the tool in each sampling period. The real-time approach produces smoother surfaces and requires substantially less machining time compared to conventional off-line approaches. The propose real-time control method based of the curvature theory of a ruled surface may give new methodology of precision 5-axis machine control.

• Steel and Composite Structures
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• 제23권1호
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• pp.41-51
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• 2017

A $C^0$ FE model developed based on an efficient higher order zigzag theory is used for hygrothermal analysis of laminated composite plates. The $C^0$ FE model satisfies the inter-laminar shear stress continuity at the interfaces and zero transverse shear stress conditions at plate top and bottom. In this model the first derivatives of transverse displacement have been treated as independent variables to circumvent the problem of $C^1$ continuity associated with the above plate theory. In the present theory the above mentioned $C^0$ continuity of the present element is compensated in the stiffness matrix formulation by using penalty parameter approach. In order to avoid stress oscillations observed in the displacement based finite element, the stress field derived from temperature/moisture fields (initial strains) must be consistent with total strain field. Special steps are introduced by field consistent approach (e.g., sampling at gauss points) to compensate this problem. A nine noded $C^0$ continuous isoparametric element is used in the proposed FE model. Comparison of present numerical results with other existing solutions shows that the proposed FE model is efficient, accurate and free of locking.

• Structural Engineering and Mechanics
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• 제40권2호
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• pp.191-213
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• 2011

This paper presents an improved 8-node shell element for the analysis of plates and shells. The finite element, based on a refined first-order shear deformation theory, is further improved by the combined use of assumed natural strain method. We analyze the influence of the shell element with the different patterns of sampling points for interpolating different components of strains. Using the assumed natural strain method with proper interpolation functions, the present shell element generates neither membrane nor shear locking behavior even when full integration is used in the formulation. Further, a refined first-order shear deformation theory, which results in parabolic through-thickness distribution of the transverse shear strains from the formulation based on the third-order shear deformation theory, is proposed. This formulation eliminates the need for shear correction factors in the first-order theory. Numerical examples demonstrate that the present element perform better in comparison with other shell elements.

• The Journal of Asian Finance, Economics and Business
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• 제8권5호
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• pp.445-454
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• 2021

Leader and leadership are one of the important aspects in the life of a country. This study aims to predict the intention of young voters to vote for state leader elections by expanding the theory of planned behavior to the Indonesian context. Apart from the importance of the presidential election, research rarely uses the theory of planned behavior, and to the best of researchers' knowledge, there are no studies that have applied the theory of planned behavior to predict the intention to vote for the president. Therefore, this study is an attempt to fill that gap. Two hundred questionnaires were distributed using non-probability purposive sampling. Data analysis was carried out using the structural equation modeling (SEM) approach. The results showed that attitude and behavior control were positively related to voters' intention to elect presidential candidates. Furthermore, information from social media also has a positive relationship with the attitude of choosing presidential candidates. However, the results also show that subjective norms do not have a significant relationship with voters' intention. This study contributes knowledge to researchers, practitioners, and policymakers about the factors that influence youth intention to vote in Indonesia, namely, attitudes, perceived behavior control, and information from social media.

• The Journal of Asian Finance, Economics and Business
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• 제8권3호
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• pp.1163-1169
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• 2021

This study aims to obtain empirical evidence regarding the effect of the fraud pentagon theory on financial statement fraud. The novelty of this study is the use of factor analysis to consolidate the five elements of the fraud pentagon into just one factor, which, to the knowledge of the researcher, no one else has done to research the effect of pentagon fraud on financial statement fraud. This study uses both agency theory and fraud pentagon theory. The population of this study consists of state-owned companies listed on the Indonesia Stock Exchange. The research period in this study is from 2014 to 2019. The data used in this study is secondary data obtained from the company's annual financial statements. A purposive sampling technique was used to determine the research sample. The selected companies total 20. Factor analysis and simple linear regression analysis method were used as research the methods. Based on the research results, it was found that the fraud pentagon theory had a positive effect on the financial statement fraud of state-owned companies listed on the Indonesia Stock Exchange. High level of the pentagon fraud on a company leads to a higher indication of financial statement fraud.

• Asian Journal of Business Environment
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• 제12권2호
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• pp.13-28
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• 2022

Purpose: Natural products are becoming gradually popular because of their health - related benefits and consumers' environmental awareness. However, research in this field remains limited, the present study attempts to address this research gap by measuring the influencing levels of the antecedents on natural product brand love. Research design, data and methodology: The study employs S-O-R (Stimulus - Organism - Response) framework together with Innovation Resistance Theory and Dual-Factor Theory to propose the research model, in which health and environmental stimuli influence both of facilitators and inhibitors of internal states or organism, and then shape purchase intention and brand love as consumers' responses. The mixed research method is designed with the application of structural equation model (SEM) to analyze 530 consumers collected by convenience sampling. Results: The results revealed that two chosen stimuli, including health awareness and environmental concern were positively related to both facilitators (natural content and regional products) and inhibitors (image barrier and usage barrier) and these four factors were significantly associated to purchase intention and brand love. Furthermore, purchase intention played the mediating role on the relationship between the four organisms and brand love. Conclusions: The originality of this paper is extend S-O-R theory into natural product context with mediating effects in an emerging economy. The findings make theoretical contribution on consumer behavior and managerial implication.

• 시큐리티연구
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• 제43호
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• pp.99-120
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• 2015

본 연구는 계획된 행동이론을 적용하여 민간경비원의 건강행동을 분석하는데 주요 목적이 있다. 이상의 목적을 달성하기 위하여 서울 경기 지역에 거주하고 있는 민간경비원을 유의표집(purposive sampling)하였다. 불성실한 응답 및 이상치를 제외하고 187명의 자료가 분석에 사용되었다. 구체적인 분석 방법은 탐색적 요인분석(Exploratory Factor Analysis: EFA), Polyserial 상관분석, 각 변인간의 인과관계를 추정하기 위하여 다중회귀(multiple regression)분석과 로지스틱 회귀(logistic regression)분석을 실시하였다. 결과를 요약하면 다음과 같다. 첫째, 애착도, 행동에 대한 태도 주관적 규범, 지각된 행동 통제력은 건강행동 지속의지에 정(+)적인 영향을 미치는 것으로 나타났다. 둘째, 애착도는 행동에 대한 태도에 유의한 영향을 미치지 않는 것으로 나타났다. 셋째, 애착도는 건강행동 지속의지에 정(+)적인 영향을 미치는 것으로 나타났다. 넷째, 지각된 행동 통제력은 건강행동 실현여부에 정(+)적인 영향을 미치며 지각된 행동 통제력인 1단위 증가하면 건강행동을 실천할 가능성이 약 62.9%씩 증가하는 것으로 나타났다. 다섯째, 건강행동 지속의지는 건강행동 실현여부에 정(+)적인 영향을 미치며 지각된 행동 통제력인 1단위 증가하면 건강행동을 실천할 가능성이 약 72.3%씩 증가하는 것으로 나타났다.

• 한국항해항만학회지
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• 제38권1호
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• pp.45-52
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• 2014

프랙탈 이론은 원격센서로부터 취득한 수치표고모델이나 이미지의 복잡성을 계량화하기 위하여 광범위하게 사용되어 왔다. 프랙탈은 컴퓨터 그래픽, 공학, 지질학을 포함한 다양한 분야에서 성공적으로 응용되어 왔지만, 프랙탈 추정자들의 성능은 데이터 샘플링에 따라 달라진다. 본 논문에서는 삼각프리즘법과 새로운 샘플링법을 기반으로 프랙탈 차원을 추정하는 알고리즘을 제안한다. 제안하는 샘플링 방법은 기존의 기하학적 스텝법과 제수 스텝법의 스텝크기 합집합 중 픽셀 활용률이 문턱값(threshold value) 이상인 스텝크기만을 취해 샘플링하며, 이를 통해 픽셀 활용률을 높여 성능을 개선한다. 또한 기존의 추정법들이 $N{\times}N$ 윈도우를 기반으로 하는데 반해 제안된 방법은 $N{\times}M$ 윈도우에 확대 적용할 수 있도록 하였다. 제안한 방법은 프랙탈 수치표고모델, Brodatz의 이미지 DB와 캠퍼스에서 촬영한 이미지에 적용하여 그 효용성을 살핀다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권6호
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• pp.2730-2747
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• 2016

Due to the limitation of the bandwidth resource and capture resolution of depth cameras, low resolution depth maps should be up-sampled to high resolution so that they can correspond to their texture images. In this paper, a novel depth map up-sampling algorithm is proposed by exploiting the fractal internal self-referential feature. Fractal parameters which are extracted from a depth map, describe the internal self-referential feature of the depth map, do not introduce inherent scale and just retain the relational information of the depth map, i.e., fractal transforms provide a resolution-independent description for depth maps and could up-sample depth maps to an arbitrary high resolution. Then, an enhancement method is also proposed to further improve the performance of the up-sampled depth map. The experimental results demonstrate that better quality of synthesized views is achieved both on objective and subjective performance. Most important of all, arbitrary resolution depth maps can be obtained with the aid of the proposed scheme.