• Journal of applied mathematics & informatics
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• 제32권3_4호
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• pp.539-546
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• 2014

This paper introduces the approximation and a proposed method to deal the optimum location network selection problem such that the total cost is minimized. For the proposed method, we derived a feasible solution and the variance. To compare the performances of the approximation and the proposed method, computer simulation is also implemented. The result showed the solutions being optimum with 74% for the proposed method and 57% for the approximation. When the solutions is not optimum, maximum and average deviations are below 4% and 2% respectively. The results indicate a slightly better performance of the proposed method in a certain case.

• 대한토목학회논문집
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• 제33권5호
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• pp.1989-1998
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• 2013

최근 '자전거이용 활성화'가 서서히 사회적으로 중요성이 부각되면서 자전거 중심의 교통체계로의 전환을 위한 다양한 노력이 있어 왔으나 그 효과는 부진한 면이 있다. 본 연구에서는 자전거 주차장 등의 시설을 구축하는 데 있어서 필요한 주차장입지선정을 공학적 분석을 통해서 구현하여 보자는데 있다. 즉, 자전거 주차장의 최적 개수 및 위치를 찾는 방법을 제안하는 것이 목적인 바, 구축 모형은 Heuristic P-Median 알고리즘을 이용하였으며, 예산제약의 유무에 따라 모형을 각각 제시하였다. 모형의 적용을 위하여 시험 네트워크를 구축하고 30개의 예비 주차장 (센트로이드-수요지)을 구성하였다. 분석 결과 자전거 주차장의 입지점은 예산제약이 있는 경우 9개, 예산제약이 없는 경우 20개로 선정되었으며, 선정된 입지점들은 실제 자전거 주차장의 이용률이 높은 곳과 일치하는 것으로 나타났다. 이러한 알고리즘은 실제 공용자전거 등의 대상지, 또는 신규 예상입지선정에 활용되어 질 수 있을 것으로 판단된다. 약간의 한계와 향후연구과제에 대해서도 논하였다.

• Earthquakes and Structures
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• 제25권5호
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• pp.359-367
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• 2023

High-rise structures are considered as symbols of economic power and leadership. Developing countries like India are also emerging as centers for new high-rise buildings (HRB). As the land is expensive and scarce everywhere, construction of tall buildings becomes the best solution to resolve the problem. But, as building's height increases, its stiffness reduces making it more susceptible to vibrations due to wind and earthquake forces. Several systems are available to control vibrations or deflections; however, outrigger systems are considered to be the most effective systems in improving lateral stiffness and overall stability of HRB. In this paper, a 42-storey RCC HRB is analyzed to determine the optimum position of outriggers of different materials. The linear static analysis of the building is performed with and without the provision of virtual outriggers of reinforced cement concrete (RCC) and pre-stressed concrete (PSC) at different storey levels by response spectrum method using finite element based Extended3D Analysis of building System (ETABS) software for determining responses viz. storey displacement, base shear and storey drift for individual models. The maximum allowable limit and percentage variations in earthquake responses are verified using the guidelines of Indian seismic codes. Results indicate that the outriggers contribute in significantly reducing the storey displacement and storey drift up to 28% and 20% respectively. Also, it is observed that the PSC outriggers are found to be more efficient over RCC outriggers. The optimum location of both types of outriggers is found to be at the mid height of building.

• 한국정보통신학회논문지
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• 제18권4호
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• pp.973-985
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• 2014

본 연구는 자동차 정비업체의 설립 시에 고려해야할 입지선정요인을 선정하고 AHP(Analytic Hierarchy Process)를 이용해서 요인별로 상대적 중요도를 나타내는 가중치를 도출하는 연구이다. 자동차 정비업체는 매우 높은 설립비용이 발생함에도 불구하고 대부분은 경영자의 경험적 판단에 의지하여 입지를 선정하는 것이 현실이다. 또한 창업비용이 낮고 서비스 활동이 단순한 소규모 점포의 입지선정과 관련된 연구는 많이 진행되고 있으나 자동차 정비업체에 대한 입지선정의 연구와 사례는 부족하여 연구가 필요한 실정이다. 본 연구에서는 1급, 2급, 3급 정비업체별로 입지선정요인의 가중치를 도출하고 서로 비교분석해 보았다. 그 결과 정비업체별로 입지를 선정하는데 있어서 중요하게 고려해야할 요인이 차이가 있음을 알 수 있었다. 본 연구는 정비업체의 입지선정과 관련된 의사결정시에 발생할 수 있는 위험을 줄일 수 있도록 과학적인 방법을 제시한 것에 의의가 있다.

• 설비공학논문집
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• 제30권1호
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• pp.1-9
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• 2018

Thermal performance of a heat sink for an inverter power stack was analyzed in terms of array and installation location of an Insulated Gate Bipolar Transistor (IGBT). Thermal flow around the heat sink was calculated with a numerical model that could simulate forced convection. Thermal performance was calculated depending on the array and location of high- and low-power IGBTs considering the maximum temperature of IGBT. The optimum array and installation location were found and causes were analyzed based on results of numerical analysis. For the numerical analysis, experiment design considered the installation location of IGBT, ratio of heat generation rates of high- and low-power IGBTs, and velocity of the inlet air as design variables. Based on numerical results, a correlation that could calculate thermal performance of the heat sink was suggested and the maximum temperature of the IGBT could be predicted depending on the installation method.

• 한국항행학회논문지
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• 제15권5호
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• pp.839-844
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• 2011

기존의 위치인식 시스템을 활용한 방법으로는 적외선, 초음파, RFID, GPS, UWB, 신호 세기 등을 이용한 방법이 있지만, 각 시스템은 음영지역에서의 위치인식이 필요하다. 본 논문에서는 협력 스펙트럼 센싱(Cooperative Spectrum Sensing)을 이용해 사물이 움직이는 경로와 위치를 판단하고, 센서가 위치한 정해진 경로를 이탈할 경우에 이를 인지해 정상적인 경로로 이동할 수 있도록 도와준다. 협력 스펙트럼 센싱은 1차 사용자에게 간섭 영향을 미치지 않는 범위 내에서 전파인지 사용자에게 최적의 전송 전력과 변조 레벨을 결정할 수 있기 때문에 주파수의 사용 효율을 높일 수 있다. 본 논문에서는 협력 스펙트럼 센싱 기법을 이용한 위치인식 시스템을 제안하였다.

• 대한안전경영과학회지
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• 제10권1호
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• pp.91-105
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• 2008

Nowadays, circulation industry is taking charge of important role in improvement of competitive power on the manufacturing industry and public welfare increase of consumer, price stabilization, employment creation and so on. A lot of research have been progressing for formation of total circulation complex, but decision making for selection of location on some facility is only calculated the optimum value when correct data values are inserted. However, a lot of decision making is accomplished in situation that have little knowledge of objective and constraints and as real world is also evaluated inclusive of analyst's subjectivity about variable, indefinite and fuzzy part, so it is decreasing a reliability on evaluation result and complicating objective evaluation on various effect and negative impact. Accordingly, from under like this situation, this study is to develop location decision model of circulation complex using fuzzy theory from the intention for the most reasonable decision making in fuzzy situation based on decision making problem on conventional location and size decision that did to be satisfactory constraints necessarily.

• Structural Engineering and Mechanics
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• 제17권5호
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• pp.611-626
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• 2004

On the basis of a structural analysis of radial gate (i.e. Tainter gate), the current paper focuses on weight minimization according to the location of the arms on a radial gate. In spite of its economical significance, there are hardly any previous studies on the optimum design of radial gate. Accordingly, the present study identifies the optimum position of the support point for a radial gate that guarantees the minimum weight satisfying the strength constraint conditions. This study also identifies the optimum position for 2 or 3 radial arms with a convex cylindrical skin plate relative to a given radius of the skin plate curvature, pivot point, water depth, ice pressure, etc. These optimum designs are then compared with previously constructed radial gates. Local genetic and hybrid-type genetic algorithms are used as the optimum tools to reduce the computing time and enhance the accuracy. The results indicate that the weights of the optimized radial gates are appreciably lower than those of previously constructed gates.

• 산업기술연구
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• 제27권A호
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• pp.141-147
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• 2007

In this paper, we define the multi-states exponential cell resident time mobility model for describing the mobility characteristics of mobile user and analyzed the total cost of the hybrid method using multi-states cell resident time. Generally, the mobile user has three states for its movement, such as staying, walking and driving. This multi-states cell resident time based hybrid method reflects the movement characteristics of mobile user and adapts the location update period according to the states of mobility speed. As a results of the performance analysis, we can get the optimum parameters of the hybrid method for multi-states based mobile users.

• 한국초지조사료학회지
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• 제18권2호
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• pp.163-170
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• 1998

This research was carried out to determine the sowing rate and row distance in Edirne province of Thrace Region in 1993 season. According to the results of some important characteristics of sorghum and their interactions were statistically significant. In Havsa and Uzunk'opr& the plant height were 70.36 and 95.28cm respectively, within each sowing rate were not significant. Number of tiller were not significant in distance and individual location Increasing the sowing rate kom I to 3 kg/da and the location Havsa and Umnkoprii resulted in significant stem diameter variation. Variation in 6-esh fodder yield has been found significant in row distance sowing rate and location 1 kglda seed rate with 30 cm row distance together are recommended to the farmer community to obtain the optimum profit.