• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.718-721
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• 1996

In this work, an effective stiffness generated by internal loading for a planar 3 degrees of freedom RCC mechanism is investigated. For this purpose, the internal kinematic analysis and antagonistic stiffness modeling for this mechanism are performed. It is shown that the antagonistic stiffness could be effectively created at the center of the mechanism in its symmetric configuration.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.323-324
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• 2013

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.801-802
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• 2011

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.93-94
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• 2011

• 한국정밀공학회지
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• 제20권7호
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• pp.185-192
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• 2003

This paper proposes an efficient mechanism design system of multi-stage gear drives including not only parallel shaft gears but also non-parallel gears such as bevel and worm gear drives. The system automatically generates three dimensional structures of specification-adjusted mechanisms, and shows the sorted list of the mechanisms according to the evaluation result by using a fuzzy expert system. The list can be used as reliable candidates of the spatial mechanism structures of multi-stage gear drives. Thus, it is expected that the system can increase the efficiency of design and cut off the expenses of preliminary design considerably.

• 대한기계학회논문집A
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• 제32권2호
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• pp.202-208
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• 2008

A 6 DOF Multi axis simulation table (MAST) is used to perform vibration and fatigue tests for parts or assemblies of automobiles, aircraft, or other systems. It consists of a table and 6 linear actuators. For its attitude control, we have to adjust the lengths of 6 actuators properly. The system is essentially a parallel mechanism. Three actuators are connected to the table directly and other three actuators are connected indirectly. Because of these, the MAST shows also a serial mechanism#s property: the inverse kinematics is more complicated than a pure parallel mechanism and each actuator can operate independently. The authors have performed a kinematics analysis of the 6 DOF MAST. We have presented an analytical and a numerical solution for the inverse and forward kinematics, and we have verified the solutions by a 3D CAD software.

• Tribology and Lubricants
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• 제24권6호
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• pp.326-331
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• 2008

The contact surfaces between mold and target should be in parallel for a proper imprinting process. However, large size of contacting area makes it difficult for both mating surfaces (mold and target planes) to be in all uniform contact with the expected precision level in terms of thickness and position. This is caused by the waviness of mold and target although it is very small relative to the area scale. The gripping force for both mold and target by the vacuum chuck is other major effect to interrupt the uniform contact, which must be avoided in imprinting mechanism. In this study, the cause of non-conformal contact mechanism between mold and target is investigated with the consideration of deformation due to the vacuum gripping for the size $470{\times}370\;mm^2$ LCD panel.

• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2006년도 춘계학술대회
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• pp.269-272
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• 2006

Surface contacts between mold and target should be in parallel for the imprinting mechanism. However, the size of contacting area makes it difficult for both mating surfaces to be in all contact because of precision level of the imprinting machine and the waviness of mold and target. The gripping force for both mold and target with the vacuum chuck is also major effect to interrupt the full contact, which must be avoided in imprinting mechanism. In this study, the preliminary study for the causes of non-uniformity of contacting surfaces such as mold and target is performed with $470{\times}370mm^2$ LCD panel size.

• 대한기계학회논문집
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• 제13권5호
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• pp.855-861
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• 1989

본 연구에서는 평행 사변형 구조를 갖는 매니퓰레이터의 운동에너지와 포텐셜 에너지를 구하고, 운동 에너지 식에서 매니퓰레이터 관성 모멘트 행렬 (manipulator inertia matrix)를 구한다.

• 정보처리학회 논문지
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• 제13권9호
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• pp.413-420
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• 2024

RISC-V는 오픈소스 명령어 집합 아키텍처로, 다양한 하드웨어 구현에서 사용되며, RV64I 기본 명령어 집합과 16개의 표준 확장을 통해 시스템 요구 사항에 맞게 유연하게 확장할 수 있다. 현재 RISC-V 아키텍처에서는 반환 주소를 보호하기 위해 쉐도우 스택 기법을 사용하고 있다. 본 논문에서는 RISC-V 아키텍처에서 컴팩트 쉐도우 스택 메커니즘과 병렬 쉐도우 스택 메커니즘의 성능을 SPEC CPU 2017 및 beebs 벤치마크를 사용하여 비교하였다. 실험 결과, 병렬 쉐도우 스택 메커니즘이 컴팩트 쉐도우 스택 메커니즘보다 더 높은 오버헤드를 보이는 것으로 나타났다. 이는 RISC-V 아키텍처의 한계로 인해 병렬 메커니즘의 효율성이 떨어짐을 시사하며, 따라서 컴팩트 쉐도우 스택이 RISC-V 아키텍처에 더 적합함을 보여준다. 또한 본 논문에서 기존 RISC-V 쉐도우 스택의 보안상 한계를 파악하고, RISC-V의 안전한 수행 환경을 보장하기 위해 쉐도우 스택 메커니즘의 성능과 보안성을 향상시키는 방향을 제시한다.