• Journal of Power Electronics
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• 제17권2호
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• pp.411-421
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• 2017

An approach based on a 2D lumped model is presented to quantify the voltage transfer gain (VTG) in power converter low power planes. The advantage of the modeling approach is the ease with which typical noise reduction devices such as decoupling capacitors or ferrite beads can be integrated into the model. This feature is enforced by a new modular approach based on effective matrix partitioning, which is presented in the paper. This partitioning is used to decouple power plane equations from external device impedance, which avoids the need for rewriting of a whole set of equation at every change. The model is quickly solved in the frequency domain, which is well suited for an automated layout optimization algorithm. Using frequency domain modeling also allows the integration of frequency-dependent devices such inductors and capacitors, which are required for realistic computation results. In order to check the precision of the modeling approach, VTGs for several layout configurations are computed and compared with experimental measurements based on scattering parameters.

• 한국구조물진단유지관리공학회 논문집
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• 제21권2호
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• pp.95-102
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• 2017

본 연구는 철근상세(대각선 및 수평 철근상세)가 실규모 연결보의 구조성능에 미치는 영향을 평가하기 위하여 실시되었다. 연결보의 시공성 및 경제성을 향상시키기 위하여 고강도 철근(SD500 및 SD600)을 사용하였다. 반복하중이 작용하는 동안 연결보의 순경간(양쪽 전 단벽 사이의 간격)을 유지하기 위하여 강체 프레임 및 링크조인트를 설치하였다. 실험결과 대각선 철근상세을 적용한 연결보가 수평 철근상세 연결보에 비해 높은 연성을 나타내었다. AC1318-14 기준은 대각선 철근상세의 연결보 설계에는 적용이 가능할 것으로 판단되나, 수평 철근상세 연결보의 최대내력은 과대평가하는 것으로 나타났다. ASCE 41-13에서 제시된 연결보의 유효강성은 대각선 및 수평 철근상세를 적용한 연결보의 실험결과를 과대평가하고 있는 것으로 판단된다.

• 한국정밀공학회지
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• 제19권7호
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• pp.125-132
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• 2002

This paper shows an experimental magnetic levitation table using one degree-of-freedom active control. The magnetic levitation table using repulsions of permanent magnets was theoretically presented already. Thus the objective of this paper is to prove stable levitation with only one degree-of-freedom active control experimentally. For the design of the system, at first, permanent magnets are selected. Secondly, the spring constants of the virtual spring are obtained by simulation. Thirdly, the moving magnets are arranged using a stable layout relation. Fourthly, a linear voice coil motor is designed. Finally, the magnetic levitation system is manufactured. The phenomenon of stable levitation in the manufactured table is proven by means of dynamic time and frequency responses. The differences between the theoretical natural frequencies and experimental ones are analyzed. Also, stable range in the control direction is shown experimentally.

• 융합신호처리학회논문지
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• 제4권1호
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• pp.64-70
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• 2003

최근 VLSI 회로 설계는 자동 레이아웃(automatic layout) 들을 사용하여 효과적으로 이루어지고 있다. 자동 레이아웃은 VLSI 칩 상에 모듈들의 위치를 결정하는 배치와 각 모듈간을 상호 연결하는 배선 두 가지의 중요한 기능으로 구성되어 있다. VLSI 칩의 성능과 면적은 이 두 가지의 기능을 수행하는 알고리즘의 성능에 따라 크게 좌우된다. 채널 배선은 VLSI 설계 과정중의 하나로, 글로벌 배선을 수행한 후 각 배선 영역에 할당된 네트들을 트랙에 할당하여 구체적인 네트들의 위치를 결정하는 문제이며, 네트들이 할당된 트랙의 수를 최소화하는 문제이다. 본 논문에서는 4-레이어 채널 배선 문제를 해결하기 위한 네트리스트 분할 문제에 대하여 유전자 알고리즘(genetic algorithm; GA)을 이용한 해 공간 탐색(solution space search) 방식을 제안하였으며, 제안한 방식을 여러 문제들에 대해 시뮬레이티드 어닐링 알고리즘과 비교, 분석한 결과 최적, 최악 및 평균비용 측면에서 더 좋은 결과를 얻을 수 있었다.

• Journal of the Korean Wood Science and Technology
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• 제51권4호
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• pp.239-252
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• 2023

In this study, bending and compression strength tests were performed to investigate effect of composition of layer layout of Larix cross-laminated timber (CLT) on mechanical properties. The Larix CLT consists of five laminae, and specimens were classified into four types according to grade and composition of layer. The layer's layout were composited as follows 1) cross-laminating layers in major and minor direction (Type A), and 2) cross-laminating external layer in major direction and internal layer applied grade of layer in minor direction (Type B). E12 and E16 were used as grades of lamina for major direction layer of Type A and external layer of Type B according to KS F 3020. In results of the bending test of CLT using same grade layer according to layer composition, the modulus of elasticity (MOE) of Type B was higher than Type A. In case of prediction of bending MOE of Larix CLT, the experimental MOE was higher than 1.00 to 1.09 times for Shear analogy method and 1.14 to 1.25 times for Gamma method. Therefore, it is recommended to predict the bending MOE for Larix CLT by shear analogy method. Compression strength of CLT in accordance with layer composition was measured to be 2% and 9% higher for Type A using E12 and E16 layers than Type B, respectively. In failure mode of Type A, progress direction of failure generated under compression load was confirmed to transfer from major layer to minor layer by rolling shear or bonding line failure due to the middle lamina in major direction.

• Architectural research
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• 제10권2호
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• pp.1-10
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• 2008

The study is to find possibilities and problems of a small-scale modification on movable storage furniture as an answer to the residents' needs. The study selected one of the renovated housing units at "KYUDOGAKUSHA" as a case study. "KYUDOGAKUSHA" was designed by architect Takeda Goichi in 1926 and was renovated in 2006. The study investigates major two aspects of movable storage furniture, which includes the furniture's layout planning and technical issues of assembling and moving moveable storage furniture. The experimental test result shows that, 1) It is clear that island type of movable storage furniture's layout can facilitate the residents'small-scale modification even though the residents are untrained. 2) To increase the assembling efficiency, the study found that it is necessary to improve the movable storage furniture's casters so that furniture can rotate. Certain moveable furniture which played a role as a connector between other furniture pieces was not able to move vertically and caused a load on other connected furniture; this needed an improvement.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.1098-1100
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• 2005

The floorplanning problem is an essential design step in VLSI layout design and it is how to place rectangular modules as density as possible. And then, as the DSM advances, the VLSI chip becomes more congested even though more metal layers are used for routing. Usually, a VLSI chip includes several buses. As design increases in complexity, bus routing becomes a heavy task. To ease bus routing and avoid unnecessary iterations in physical design, we need to consider bus planning in early floorplanning stage. In this paper, we propose a floorplanning method for topological constraint consisting of bus constraint and memory constraint. The proposed algorithms based on Genetic Algorithm(GA) is adopted a sequence pair. For selection control, new objective functions are introduced for topological constraint. Studies on floor planning and cell placement have been reported as being applications of GA to the LSI layout problem. However, no studies have ever seen the effect of applying GA in consideration of topological constraint. Experimental results show improvement of bus and memory constraint.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 춘계학술대회논문집
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• pp.844-847
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• 2008

As customer's demands are varying, the type of floor plan of apartment is changed into expanded type with balcony unified to living room from general type with balcony separated from living room and so is changing the layout of L(living room), D(dining room) and K(kitchen). This study aims to examine how the type of floor plan of living room affects the floor impact sound insulation performance and to propose fundamental idea to floor plan layout of apartment in terms of floor impact sound reduction.

• 한국자동차공학회논문집
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• 제4권3호
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• pp.61-72
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• 1996

In this paper, the driver seat comfort of eight automobiles was studied. The joint angles and anthropometric data of eleven subjects sitting on the seating buck were investigated using the instrument devices such as scale, goniometer, vernier calipers, protractor, Martin set. The joint angles of the most comfort posture were found by experiment and compared with previous studies. The anthropometric data of Korean(1992 year surveys) and American(1970∼1974 year) were applied to evaluate the driver seat layout of Korean automobile. The joint angles of the most comfort posture for eleven subjects were obtained with experimental results. The joint angles were agreed with reference angles. The driver seat layout was not suited to seat length and acceleratorseatpan forward distance in 5 percentiles female, pedal separation and seatpan-roof height in 95 percentiles male. Korean automobiles were not suited to seatpan length and steering wheelseatpan clearance, floor-roof height for American 95 percentiles male. The driver anthropometric dimensions were more suitable to middle size than small size automobiles.

• 한국정밀공학회지
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• 제20권3호
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• pp.35-41
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• 2003

The multihole blanking of thin sheet metal using progressive die set is an important process on production of precision electronic machine parts such as IC leadframe. In this paper, in order to investigate the influence of blanking order on the final lead profile and deformed configuration, simulation technique for progressive blanking process is proposed and analyzed by LS-DYNA. The results of FE-simulations are in good agreement with the experimental results. Consequently, from the results of FE-analysis based on the procedure proposed in this paper, it is possible to predict the deformation of lead and to manufacture high precision leadframes in progressive blanking process and these results might be used as a guideline to develop layout design system in multihole blanking process.