• Journal of Computational Design and Engineering
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• 제2권2호
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• pp.88-95
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• 2015

Recently, fiber composite materials have been attracting attention from industry because of their remarkable material characteristics, including light weight and high stiffness. However, the costs of products composed of fiber materials remain high because of the lack of effective manufacturing and designing technologies. To improve the relevant design technology, this paper proposes a novel simulation method for deforming fiber materials. Specifically, given a 3D model with constant thickness and known fiber orientation, the proposed method simulates the deformation of a model made of thick fiber-material. The method separates a 3D sheet model into two surfaces and then flattens these surfaces into two dimensional planes by a parameterization method with involves cross vector fields. The cross vector fields are generated by propagating the given fiber orientations specified at several important points on the 3D model. Integration of the cross vector fields gives parameterization with low-stretch and low-distortion.

• International Journal of CAD/CAM
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• 제3권1_2호
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• pp.97-109
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• 2003

A large scale polygon models are often used to approximately represent 3D CAD models in Digital Engineering environment such as DMU (Digital Mockups) and network based collaborative design. However, they are not suitable for distribution on the network and for interactive rendering. We introduce a new coding system based on subdivision schemes called S-CODE system. In this system, it is possible to highly compress the model with sufficient accuracy and to view the model efficiently in a level of detail (LOD) fashion. The method is based on subdivision surface fitting by which a subdivision surface and curves which approximate a face of a CAD model are generated. We also apply a subdivision method to analytic surfaces such as conical and cylindrical surfaces. A prototype system is developed and used for evaluation with reasonably complicated data. The results show that the method is useful as a CAD data coding system.

• 한국지반공학회논문집
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• 제26권5호
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• pp.27-36
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• 2010

본 연구에서는 동상성이 높은 대상 시료에 입경이 다른 3종의 폐타이어분말을 대상으로 서멀 프루브법을 이용하여 $-20^{\circ}C{\sim}+10^{\circ}C$의 온도변화에 따른 열전도율을 실측하는 것과 동시에 펄스형NMR장치를 이용하여 동토중의 부동수분량을 측정하였고 이를 온도함수로 나타내었다. 또한 열전도율 계산모델의 하나인 2상계모델을 발전시켜 3상계 동결토영역에 적용 가능한 새로운 모델을 제안하였다.

• 대한전자공학회논문지TC
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• 제46권1호
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• pp.89-93
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• 2009

본 논문은 에너지 검출기에 시간 지연 장치를 채택하여 복수번의 확인 과정을 갖는 향상된 스펙트럼 검출기에서 센싱 시간에 따른 성능의 영향을 알아본다. SNR은 1dB, 그리고 오보 확률은 0.1로 고정하고 3, 60, 100km/h의 다양한 이동 속도를 고려한 스즈키 채널 하에서 시뮬레이션을 통해 센싱 성능을 고찰하고 이를 기존의 에너지 검출기의 경우와 비교한다.

• Industrial Engineering and Management Systems
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• 제11권2호
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• pp.170-175
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• 2012

In this paper, a procedure using a genetic algorithm (GA) and a heuristic local search (HLS) is proposed for solving facility rearrangement problem (FRP). FRP is a decision problem for stopping/running of facilities and integration of stopped facilities to running facilities to maximize the production capacity of running facilities under the cost constraint. FRP is formulated as an integer programming model for maximizing the total production capacity under the constraint of the total facility operating cost. In the cases of 90 percent of cost constraint and more than 20 facilities, the previous solving method was not effective. To find effective alternatives, this solving procedure using a GA and a HLS is developed. Stopping/running of facilities are searched by GA. The shifting the production operation of stopped facilities into running facilities is searched by HLS, and this local search is executed for one individual in this GA procedure. The effectiveness of the proposed procedure using a GA and HLS is demonstrated by numerical experiment.

• 한국산림과학회지
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• 제31권1호
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• pp.62-77
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• 1976

적정벌채량(適正伐採量)을 결정(決定)하는 일은 삼림경리(森林經理)의 주요임무(主要任務)라 할 수 있다. 그러므로 이제까지 많은 수확예정법(收穫豫定法)이 소개되었다. 그것들 중(中)에는 임업경영(林業經營)에 실제로 채용된 것도 있으나 대부분(大部分)의 방법(方法)들은 채용되지 않고 있다. 여기에서는 감단율법(減段率法)이라는 새로운 수확예정법(收穫豫定法)을 소개한다. 이 방법(方法)은 이론적(理論的)으로 흥미(興味)있고 실용성(實用性)있는 방법(方法)이라고 알려져 있다.

• Korea-Australia Rheology Journal
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• 제15권1호
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• pp.19-25
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• 2003

Since the microstructure of functional thin films depends on the dispersion characteristics of dense slurry, it is important to control the agglomerative nature of slurries under processing. The present authors have been discussing the model prediction of agglomerative nature and local rate of agglomeration in dense suspensions. The experiments have been peformed under shear flow using the nearly spherical and oblate type graphite particles. In this study, the experiment has been conducted using water and glycerol as dispersion media. Stress control type rheometer was used to measure the slurry rheology. Local agglomeration of graphite particles has been predicted by using Usui's model. The experimental results show that both the shape and slurry processing method affect on the local dispersion condition. The agglomeration formed by oblate type graphite particles seems to be more difficult to break up than that of spherical particles.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.1920-1923
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• 1991

An online RF power measurement is needed for the full-bridged MOS-FET RF power inverter because the output current and/or voltage waveform is other than sinusoidal. In order to satisfy the requirement, the online measurement of the output power of this type of RF power inverter by the use of the PC-98 personal computer has been presented. The current and voltage waveforms are sensed by the digital oscilloscope probes so as to obtain the instantaeous power and they are entered into the PC98 personal computer so as to average the instantaneous powers. The RF power of up to 1 kw at 1 MHz measured for the power inverter at the output transformer. This method was confirmed to be applied to evaluate the load resistance change with temperature.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2005년도 BIOINFO 2005
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• pp.348-353
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• 2005

In this paper we discuss the formulation and the analysis of a signaling pathway by Petri nets. In order to explicitly and formally describe the molecular mechanisms and pathological characteristics of signaling pathways, we propose a new modeling method to construct signaling pathways on the basis of formal representation of Petri net. Our proposed extended algorithm effectively finds basic enzymic components of signaling pathways by employing T-invariants of Petri nets with considering the origination leading to an occurrence of inhibition functions than existing methods. An application of the proposed algorithm is given with the example of Interleukin-1 and Interleukin-6 signaling pathways.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.18-21
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• 2005

The impact of the interannual climatic variability on the vegetation sensitively appears in the timing of phenological events such as green-up, mature, and senescence. Therefore, an accurate and temporally high-resolution NDVI dataset will be required for analysis on the interannual variability of the climate-vegetation relationship. We constructed a daily 8km NDVI dataset over Eurasia based on the 8km tiled data of Pathfinder A VHRR Land (PAL) Global daily product. Cloud contamination was successfully reduced by Temporal Window Operation (TWO), which is a method to find optimized upper envelop line of the NDVI seasonal change. Based on the daily NDVI time series from 1982 to 2000, an accurate (daily) interannual change of the phenological events will be analyzed.