• Title/Summary/Keyword: MINIMUM AREA

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Optimal Design of Location Management Using Particle Swarm Optimization (파티클군집최적화 방법을 적용한 위치관리시스템 최적 설계)

  • Byeon, Ji-Hwan;Kim, Sung-Soo;Jang, Si-Hwan;Kim, Yeon-Soo
    • Korean Management Science Review
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    • v.29 no.1
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    • pp.143-152
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    • 2012
  • Location area planning (LAP) problem is to partition the cellular/mobile network into location areas with the objective of minimizing the total cost in location management. The minimum cost has two components namely location update cost and searching cost. Location update cost is incurred when the user changes itself from one location area to another in the network. The searching cost incurred when a call arrives, the search is done only in the location area to find the user. Hence, it is important to find a compromise between the location update and paging operations such that the cost of mobile terminal location tracking cost is a minimum. The complete mobile network is divided into location areas. Each location area consists of a group of cells. This partitioning problem is a difficult combinatorial optimization problem. In this paper, we use particle swarm optimization (PSO) to obtain the best/optimal group of cells for 16, 36, 49, and 64 cells network. Experimental studies illustrate that PSO is more efficient and surpasses those of precious studies for these benchmarking problems.

Characteristics of Seasonal Mean Diurnal Temperature Range and Their Causes over South Korea (우리나라에서 계절별 일교차의 분포 특성과 그 원인)

  • Suh, Myoung-Seok;Hong, Seong-Kun;Kang, Jeon-Ho
    • Atmosphere
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    • v.19 no.2
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    • pp.155-168
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    • 2009
  • Characteristics of seasonal mean diurnal temperature range (DTR) and their causes over South Korea are investigated using the 60 stations data of Korea Meteorological Administration from 1976 to 2005. In general, the seasonal mean DTR is greatest during spring (in inland area) and least during summer (urban and coastal area). The spatial and seasonal variations of DTR are closely linked with the land surface conditions (especially vegetation activity and soil moisture) and atmospheric conditions (cloud amount, precipitation, local circulation). The seasonal mean DTR shows a decreasing trend at the major urban areas and at the north-eastern part of South Korea. Whereas, it shows an increasing trend at the central area of the southern part. Decreasing and increasing trends of DTR are more significant during summer and fall, and during spring and winter. The decrease (increase) of DTR is mainly caused by the stronger increase of daily minimum (maximum) temperature than daily maximum (minimum) temperature. The negative effects of precipitation and cloud amount on the DTR are greater during spring and at the inland area than during winter and at the coastal area. And the effect of daytime precipitation on the DTR is greater than that of nighttime precipitation.

A Study on the Characteristics of Space Programs for Senior Center in Japan (일본 노인복지센터의 공간구성 특성에 관한 연구)

  • 소준영
    • Korean Institute of Interior Design Journal
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    • no.29
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    • pp.153-162
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    • 2001
  • This study suggests the basic data required in setting up the standard for the architectural planning of Korean senior center by analyzing the standard and current situation of a senior center in Japan that has the welfare facility system similar to that of Korea and understanding its architectural characteristics. 1) Basic spaces that constitute the senior center in Japan are meeting room, lecture room, library, multipurpose meeting room, conference room, game-recreation room, kitchen, lounge, locker room and office. ADL, kitchen, relaxing room, private bathroom, and special bathroom are needed for adult day care as establishments as an annex and work room is also required for Job training. 2) The area of a senior center is calculated in consideration of its space organization that are required as basic. For the type "A", minimum area of 1,256.42 $m^2$2 and maximum area of 2,050.56$m^2$ and for the type "B", minimum area of 812000$m^2$ and maximum area of 1,604.14$m^2$ are suggested as optimum areas. 3) The circulation planning is presented by the connected between the space organization as well as the circulation system in day care center.

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Swimming behavior analysis of small box jellyfish (Carybdea brevipedalia)

  • Yongbeom Pyeon;Jinho Chae;Wooseok Oh;Doo Jin Hwang;Kyounghoon Lee
    • Fisheries and Aquatic Sciences
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    • v.27 no.1
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    • pp.1-6
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    • 2024
  • In this study, the swimming behavior of a small box jellyfish (Carybdea brevipedalia), which consists of inhaling external seawater and expelling it through its mouth to generate forward thrust, was characterized using particle image velocimetry (PIV). The flow rate and structure during the suction and discharge process were quantitatively analyzed. During swimming, there was a change in the ratio of the internal area during inhalation and expulsion. Specifically, there was a 1.10-fold difference between the maximum area after inhalation and the minimum area after discharge. The maximum distance traveled after discharge was inversely proportional to the size of the inner area, with a 2.48-fold difference in the minimum distance traveled after suction. Depending on the propulsion stage, the inner area decreased and then increased in proportion to the moving distance and speed. The moving distance of the small box jellyfish was measured for each period. The speed for each swimming stage increased and then decreased at intervals of 0.15 to 0.2 seconds, and the suction and discharge cycle period was measured at approximately 0.5 seconds. Collectively, our findings provide a methodological basis for studying the swimming behavior of small and highly active trailing jet jellyfish, as well as the biological mechanisms that determine this behavior.

Estimation and Evaluation of Reanalysis Air Temperature based on Mountain Meteorological Observation (산악기상정보 융합 기반 재분석 기온 데이터의 추정 및 검증)

  • Sunghyun, Min;Sukhee, Yoon;Myongsoo, Won;Junghwa, Chun;Keunchang, Jang
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.24 no.4
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    • pp.244-255
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    • 2022
  • This study estimated and evaluated the high resolution (1km) gridded mountain meteorology data of daily mean, maximum and minimum temperature based on ASOS (Automated Surface Observing System), AWS (Automatic Weather Stations) and AMOS (Automatic Mountain Meteorology Observation System) in South Korea. The ASOS, AWS, and AMOS meteorology data which were located above 200m was classified as mountainous area. And the ASOS, AWS, and AMOS meteorology data which were located under 200m was classified as non-mountainous area. The bias-correction method was used for correct air temperature over complex mountainous area and the performance of enhanced daily coefficients based on the AMOS and mountainous area observing meteorology data was evaluated using the observed daily mean, maximum and minimum temperature. As a result, the evaluation results show that RMSE (Root Mean Square Error) of air temperature using the enhanced coefficients based on the mountainous area observed meteorology data is smaller as 30% (mean), 50% (minimum), and 37% (maximum) than that of using non-mountainous area observed meteorology data. It indicates that the enhanced weather coefficients based on the AMOS and mountain ASOS can estimate mean, maximum, and minimum temperature data reasonably and the temperature results can provide useful input data on several climatological and forest disaster prediction studies.

the Design Methodology of Minimum-delay CMOS Buffer Circuits (최소 지연시간을 갖는 CMOS buffer 회로의 설계 기법)

  • 강인엽;송민규;이병호;김원찬
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.25 no.5
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    • pp.509-521
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    • 1988
  • In the designs of integrated circuits, the buffer circuits used for driving a large capacitive load from minimum-structured logic circuit outputs have important effects upon system throughputs. Therefore it is important to optimize the buffer circuits. In this paper, the principle of designing CMOS buffer circuits which have the minimum delay and drive the given capacitive load is discussed. That is, the effects of load capacitance upon rise time, fall time, and delay of the CMOS inverter and the effects of parasitic capacitances are finely analysed to calculate the requested minimum-delay CMOS buffer condition. This is different from the method by C.A. Mead et. al.[2.3.4.]which deals with passive-load-nMOS buffers. Large channel width MOS transistor stages are necessary to drive a large capacitive load. The effects of polysilicon gate resistances of such large stages upon delay are also analysed.And, the area of buffer circuits designed by the proposed method is smaller than that of buffer circuits designed by C.A. Mead's method.

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Prediction of Development Process of the Spherical Flame Kernel (구형 화염핵 발달과정의 예측)

  • 한성빈;이성열
    • Transactions of the Korean Society of Automotive Engineers
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    • v.1 no.1
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    • pp.59-65
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    • 1993
  • In a spark ignition engine, in order to make research on flame propagation, attentive concentration should be paid on initial combustion stage about the formation and development of flame. In addition, the initial stage of combustion governs overall combustion period in a spark ignition engine. With the increase of the size of flame kernel, it could reach initial flame stage easily, and the mixture could proceed to the combustion of stabilized state. Therefore, we must study the theoretical calculation of minimum flame kernel radius which effects on the formation and development of kernel. To calculate the minimum flame kernel radius, we must know the thermal conductivity, flame temperature, laminar burning velocity and etc. The thermal conductivity is derived from the molecular kinetic theory, the flame temperature from the chemical reaction equations and the laminar burning velocity from the D.K.Kuehl's formula. In order to estimate the correctness of the theoretically calculated minimum flame kernel radius, the researcheres compared it with the RMaly's experimental values.

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An Approximation Scheme For A Geometrical NP-Hard Problem (기하학적 NP-hard 문제에 대한 근사 접근법)

  • Kim, Joon-Mo
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.44 no.8
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    • pp.62-67
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    • 2007
  • In some wireless sensor networks, the sensor nodes are required to be located sparsely at designated positions over a wide area, introducing the problem of adding minimum number of relay nodes to interconnect the sensor nodes. The problem finds its form in literature: the Minimum number of Steiner Points. Since it is known to be NP-hard, this paper proposes an approximation scheme to estimate the minimum number of relay nodes through the properties of the abstract from. Reducing the number of nodes in a sensor network, the amount of data exchange over the net will be far decreased.

Improving Efficiency of Minimum Dominating Set Problem using Simulated Annealing Algorithms (Simulated Annealing 알고리즘을 이용한 최소 Dominating Set 문제의 효율성 증가에 대한 연구)

  • Jeong, Tae-Eui
    • The KIPS Transactions:PartA
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    • v.18A no.2
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    • pp.69-74
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    • 2011
  • The minimum dominating set problem of a graph G is to find a smallest possible dominating set. The minimum dominating set problem is a well-known NP-complete problem such that it cannot be solved in polynomial time. Heuristic or approximation algorithm, however, will perform well in certain area of application. In this paper, we suggest three different simulated annealing algorithms and experimentally show better efficiency improvement by applying these algorithms to the graph instances developed by DIMACS.

A NEW ALGORITGMIC HEURISTICS FOR THE SYNTHESIS OF OPTIMAL HEAT EXCHANGER NETWORT

  • Cho, Y.S.
    • 제어로봇시스템학회:학술대회논문집
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    • 1989.10a
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    • pp.819-824
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    • 1989
  • This paper proposes a new method for the discovery and design of an optimal heat exchanger network. The method is based upon the concept of pinch, a problem reduction technique and the heuristics developed in this work. It generates subproblems in a logical way and solves the subproblems by the heuristics to synthesize an optimal network structure. It is thought that the heuristics can preserve the minimum utility consumption, the minimum number of heat exchanger units, and the minimum number of stream splittings needed for a given problem. The minimum heat exchanger area for the optimal network can then be obtained by adjusting the temperatures associate with the heat exchanger in the optimal network structure. The method is applied to the problems appeared in the literatures. The results show the reductions in the number of heat exchanger units for some problems.

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