• 전기학회논문지
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• 제59권2호
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• pp.411-416
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• 2010

In this paper, an integral variable structure static output feedback controller with an integral-augmented sliding surface is designed for the improved robust control of a uncertain system under unmatched system uncertainty and matched input matrix uncertainty and disturbance satisfying some conditions. To effectively remove the reaching phase problems, an output dependent integral augmented sliding surface is proposed. Its equivalent control and ideal sliding mode dynamics are obtained. The previous some limitations is overcome in this systematic design. A stabilizing control with the closed loop exponential stability is designed for all unmatched system matrix uncertainties and proved together with the existence condition of the sliding mode on S=0. To show the usefulness of the algorithm, a design example and computer simulations are presented.

• 응용통계연구
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• 제7권2호
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• pp.289-297
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• 1994

블럭계획에서 조화행렬(concordance matrix)이 퍼뮤테이션 행렬(permutation matrix)들의 크로네커 곱(Kronecker product)의 선형결합으로 표시되면, 그러한 블럭 계획들은 특성치 C (Property C)를 갖고 특성치 C를 갖는 블럭계획들은 역행렬의 계산없이 블럭내 분석이 가능하다(Paik, 1985). $L_i$ 계획($L_i$ PBIB design)이 특성치 C에 속하는 것을 보이기 위하여, 조화행렬의 구조가 다중순환형식임을 보였다.

• 제어로봇시스템학회논문지
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• 제12권6호
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• pp.524-529
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• 2006

In this paper, we propose a method to design variable structure systems with sliding sector for multi-input multi-output systems with mismatched uncertainties in the state matrix. For the uncertain systems we define sliding sectors within which a norm of the state decreases with zero input despite of mismatched uncertainties. Using the notion of the sliding sector we give simple design algorithms of variable structure control laws that can reduce the chattering. Finally, we give a design example in order to show the effectiveness of our method.

• 한국통신학회논문지
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• 제31권2C호
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• pp.123-129
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• 2006

랜덤하게 생성된 LDPC 부호의 경우 부호화기의 복잡도가 크기 때문에 효과적인 부호화를 위하여 구조적인 설계를 필요로 한다. 본 논문에서는 효율적인 부호화기를 위해 기존에 제안된 eIRA 부호에 순환 행렬의 구조를 적용한 부호화기 구조를 제안하였다. 제안된 순환 행렬 구조는 쉬프트 레지스터를 사용하여 부호화기를 구성할 수 있으며, 순환 행렬의 사용으로 인한 성능 저하를 방지하기 위해 치환 행렬 구조에 해당하는 인터리버를 사용하였다. 제안된 부호는 LDPC 부호화기의 복잡도는 낮추면서도 기존의 부호화기의 성능과 유사한 성능을 보인다.

• 대한기계학회논문집A
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• 제20권3호
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• pp.872-881
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• 1996

The concept of homology design has been devised for the application to large telescope structure by S.v.Hoerner. It is defined that the deformation of a structure shall be called homologous, if a given geometrical relation holds, for a given number of structural points, before, during, and after the deformation. Recently, the need of homology design in the structural design has been increase due to the required precision in the structure. Some researchers have utilized the theory on the structural design with finite element method in the late 1980s In the present investigation, a simple method using geometrical equality constraints is suggested to gain homologous deformation. The previous method is improved in that the decomposition of FEM eqation, which is very expensive, is not necessary. The basic formulations of the homology design with the optimization concept are described and several practical examples are solved to verify the usefulness and validity. Especially, a back-up structure of a satellite antenna is designed by the suggested method. The results are compared with those of existing researches.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 추계학술대회 논문요약집
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• pp.28-28
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• 2003

• Communications for Statistical Applications and Methods
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• 제13권1호
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• pp.135-140
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• 2006

The paper by Paik (1985) introduced a structural property of the designs which was related to the concordance matrix $NN^{t}$ of the design. This special property was termed Property-C. The designs which have Property-C need not calculation of the generalize inverse of C matrix for solution of reduced normal equation. Paik also mentioned that some block designs belong to Property-C. This paper show the Extended Group Divisible designs defined by Hinkelmann (1964) are included in Property-C.

• Journal of Mechanical Science and Technology
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• 제15권12호
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• pp.1639-1646
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• 2001

It is often necessary that the joints characteristics should be determined in the early stage of the vehicle body design. The researches on identification of joints in a vehicle body have been performed until the recent year. In this study, the joint characteristics of vehicle structure were expressed as the condensed matrix forms from the full joint stiffness matrix. The condensed joint stiffness matrix was applied to typical T-type and Edge-type joints, and the usefulness was confirmed. In addition, it was applied to the real center pillar model and the full vehicle body in order to validate the practical application.

• Biotechnology and Bioprocess Engineering:BBE
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• 제6권5호
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• pp.311-325
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• 2001

Tissue engineering scaffolds play a critical role in regulating the reconstructed human tissue development. Various types of scaffolds have been developed in recent years, including fibrous matrix and foam-like scaffolds. The design of scaffold materials has been investigated extensively. However, the design of physical structure of the scaffold, especially fibrous matrices, has not received much attention. This paper compares the different characteristics of fibrous and foam-like scaffolds, and reviews regulatory roles of important scaffold properties, including surface geometry, scaffold configuration, pore structure, mechanical property and bioactivity. Tissue regeneration, cell organization, proliferation and differentiation under different microstructures were evaluated. The importance of proper scaffold selection and design is further discussed with the examples of bone tissue engineering and stem cell tissue engineering. This review addresses the importance of scaffold microstructure and provides insights in designing appropriate scaffold structure for different applications of tissue engineering.

• 한국통신학회논문지
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• 제35권11B호
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• pp.1704-1709
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• 2010

무기체계 시스템 개발에서는 분명히 기술 선도국이 존재하고 무기체계 개발경쟁에서 앞서 있는 것을 부인할 수 없는데, 여기에 더불어 시스템의 설계 정보에 접근이 거의 불기능하다는 것도 현실이다. 따라서 이미 배치되어 운용되고 있는 선도 시스템과 유사한 무기체계 시스템의 개발이 필요한 경우의 개발 방법론이 필요하다. 한 가지 접근 방법으로 기존에 선진국에서 개발된 유사한 시스템을 분석하여 설계 정보로 참조하고, 이를 기반으로 추가적으로 설계 최적화에 대한 노력을 수행하는 것을 제시할 수 있다. 본 연구에서는 설계정보의 접근에 제약이 있는 선진 시스템에 대해 역공학 분석을 수행하여 설계 정보를 추출하여 정리해서 대상시스템의 기반 설계 정보로 활용하고 이 설계 정보들을 DSM 기법을 활용하여 최적화 설계 구조로 개선하는 방법을 제시하였다. 시스템의 설계 예로 유도무기체계 개발에 적용하였다.