• International Journal of Automotive Technology
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• 제2권3호
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• pp.117-122
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• 2001

For a dynamic analysis of a constrained multibody system, it is necessary to have a routine for satisfying kinematic constraints. LU decomposition scheme, which is used to divide coordinates into dependent and independent coordinates, is efficient but has great difficulty near the singular configuration. Other method such as the projection matrix, which is more stable near a singular configuration, takes longer simulation time due to the large amount of calculation for decomposition. In this paper, the row space and the null space of the Jacobian matrix are proposed by using the pseudo-inverse method and the projection matrix. The equations of the motion of a system are replaced with independent acceleration components using the null space of the Jacobian matrix. Also a new hybrid method is proposed, combining the LU decomposition and the projection matrix. The proposed hybrid method has following advantages. (1) The simulation efficiency is preserved by the LU method during the simulation. (2) The accuracy of the solution is also achieved by the projection method near the singular configuration.

• 한국컴퓨터정보학회논문지
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• 제19권8호
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• pp.27-34
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• 2014

이 논문에서는 hybrid projection 함수와 rank order 필터를 이용하여 눈동자를 검출하는 방법을 제안한다. 눈썹을 눈동자로 검출하는 오류를 줄이기 위하여, hybrid projection 함수를 이용하여 얼굴 영역에서 눈썹을 검출하고 눈썹이 포함되지 않도록 눈 영역을 설정한다. 눈 영역에서 rank order 필터를 사용하여 눈동자 후보점을 찾고 위치를 보정한다. 두 눈동자 후보점을 기하학적인 제약조건을 기반으로 쌍으로 묶고 각 쌍의 두 눈에 대한 유사도를 정합을 이용하여 측정하여가장작은값을 갖는 쌍을 최종눈동자로 결정한다. BioID 얼굴데이터베이스의 얼굴 영상 700개에 대한 실험 결과 92.4%의 검출율을 얻었으며 기존 방법보다 약 21.5% 개선된 결과를 얻었다.

• 대한수학회논문집
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• 제32권2호
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• pp.447-456
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• 2017

The purpose of this paper is to introduce some strong convergence theorems for the problem of finding a common zero of a finite family of monotone operators and the problem of finding a common fixed point of a finite family of nonexpansive in Hilbert spaces by hybrid projection method.

• Nonlinear Functional Analysis and Applications
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• 제27권3호
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• pp.553-568
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• 2022

In this paper, we introduce and study two different iterative hybrid projection algorithms for solving a fixed point problem of nonexpansive mappings. The first algorithm is generated by the combination of the inertial method and the hybrid projection method. On the other hand, the second algorithm is constructed by the convex combination of three updated vectors and the hybrid projection method. The strong convergence of the two proposed algorithms are proved under very mild assumptions on the scalar control. For illustrating the advantages of these two newly invented algorithms, we created some numerical results to compare various numerical performances of our algorithms with the algorithm proposed by Dong and Lu [11].

• Structural Engineering and Mechanics
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• 제65권6호
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• pp.707-719
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• 2018

In this article, a new method is introduced to improve the local search capability of meta-heuristic algorithms using the projection of the path on the border of constraints. In a mathematical point of view, the Gradient Projection Method is applied through a new approach, while the imposed limitations are removed. Accordingly, the gradient vector is replaced with a new meta-heuristic based vector. Besides, the active constraint identification algorithm, and the projection method are changed into less complex approaches. As a result, if a constraint is violated by an agent, a new path will be suggested to correct the direction of the agent's movement. The presented procedure includes three main steps: (1) the identification of the active constraint, (2) the neighboring point determination, and (3) the new direction and step length. Moreover, this method can be applied to some meta-heuristic algorithms. It increases the chance of convergence in the final phase of the search process, especially when the number of the violations of the constraints increases. The method is applied jointly with the authors' newly developed meta-heuristic algorithm, entitled Star Graph. The capability of the resulted hybrid method is examined using the optimal design of truss and frame structures. Eventually, the comparison of the results with other meta-heuristics of the literature shows that the hybrid method is successful in the global as well as local search.

• East Asian mathematical journal
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• 제28권3호
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• pp.305-320
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• 2012

The purpose of this paper is to introduce a hybrid projection method for finding a common element of the set of solutions of a generalized equilibrium problem, the set of solutions of a variational inclusion problem and the set of common fixed points of a finite family of strict pseudo-contractions in Hilbert spaces.

• 만화애니메이션 연구
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• 통권39호
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• pp.133-156
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• 2015

매체와 기술의 발전과 함께 애니메이션은 다양한 장르적 융합을 꾀하고 있다. 모바일 디바이스가 새로운 영상 재생 매체로 보편화되면서 애니메이션은 극장이나 TV와 같은 한정된 재생 매체에서 벗어나 다양한 매체와 장소에서 관객들과 만나고 있다. 또한 다양한 기술과 예술 형태가 융합하여 애니메이션 자체의 장르 변화와 진화가 일어나고 있다. 이러한 현상 속에서 필자는 팝업북과 프로젝션 맵핑을 이용한 새로운 애니메이션 상영방식을 제안하고자 한다. 즉 팝업북을 통해 입체물을 만들고 그 입체물에 영상을 투사하여 기존의 평면 스크린을 통해 관람하던 방식이 아닌 새로운 방식의 애니메이션 관람 형태를 만들고자 한다. 이러한 상영방식은 프로젝션 맵핑과 팝업북을 이용한 선행 작품들에 의해 영감을 얻을 수 있었다. 영국의 부부작가인 데이비 맥과이어와 크리스틴 맥과이어는 팝업북과 프로젝션 맵핑을 이용한 다양한 작품들을 제작해왔다. 필자는 이 작품들을 사례 분석하여 각 작품들이 갖는 장 단점과 작품 사이 차이점들을 명확히 할 수 있었다. 또한 프로젝션 맵핑과 팝업북이 융합되면서 각 장르의 장점들이 작품들을 통해 어떻게 나타나는지도 알 수 있었다. 필자가 제안하는 상영방식은 기존의 선행 작품들과는 차이점을 분명히 갖고 있으며 연극, 프로젝션 맵핑, 팝업북, 애니메이션, 설치물 등 다양한 영역이 융합된 방식으로 Hybrid Animation Theater라 칭한다. Hybrid Animation Theater가 안정된 상영방식으로 인정받을 수 있도록 그 특징과 구조적 설계에 대해 연구하였다. 이후 프로토 타입을 제작하여 그 가능성을 증명하고 단점과 한계점, 향후 연구 방향을 제시 할 수 있었다.

• 대한수학회논문집
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• 제26권3호
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• pp.473-482
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• 2011

In this paper, mappings which are asymptotically pseudo-contractive in the intermediate sense are considered based on a hybrid projection method. Strong convergence theorems of fixed points are established in the framework of Hilbert spaces.

• 한국산업융합학회 논문집
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• 제4권1호
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• pp.87-94
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• 2001

In multibody dynamics, differential and algebraic equations which can satisfy both equation of motion and kinematic constraint equation should be solved. To solve this equation, coordinate partitioning method and constraint stabilization method are commonly used. The coordinate partitioning method divides the coordinate into independent and dependent coordinates. The most typical coordinate partitioning method arc LU decomposition, QR decomposition, projection method and SVD(sigular value decomposition).The objective of this research is to find a efficient coordinate partitioning method in flexible multibody systems and a hybrid decomposition algorithm which employs both LU and projection methods is proposed. The accuracy of the solution algorithm is checked with a slider-crank mechanism.

• 충청수학회지
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• 제23권4호
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• pp.801-812
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• 2010

In this paper, we consider the convergence of the shrinking projection method for quasi-$\phi$-nonexpansive mappings. Strong convergence theorems are established in a uniformly smooth and strictly convex Banach space which enjoys the Kadec-Klee property.