• 경영과학
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• 제19권1호
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• pp.29-38
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• 2002

Due to the rapid increase In the Internet traffic volume, ISPs are faced with the definite need of the expansion of server capacity. In order to Provide prompt services for customers and still prevent excessive facility cost, it is critical to determine the optimum level of internet server capacity. The purpose of this Paper is to provide a simple but effective strategy on the expansion of servers capacity according to the increase in internet traffic. We model an internet server as an M/G/m/m queueing system and derive an efficient method to compute the loss probability which, In turn, Is used as a basis to determine proper server capacity. The Process of estimating the traffic parameter values at each server based on log data analysis is also given. All the procedures are numerically demonstrated through the process of analyzing actual log data collected from a game company.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2005년도 춘계학술대회 논문집
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• pp.231-235
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• 2005

항로의 해상교통량 수용 능력을 평가하는 여러 기법들 중에서, 가장 간단한 수준에서 검토가 가능한 기법으로서, 범퍼 모델을 이용한 항로 교통용량 추정기법에 관하여 기술한다. 항로의 교통용량을 추정하기 위한 간단한 계산식과 실제 항로에서의 교통량을 추정하는 기법에 대하여 고찰하고, 이를 바탕으로 항로의 가동률이라는 개념을 수립하여, 이러한 모델을 우리나라 주요 항만의 진입항로에 적용하여 보았다. 본 기법은, 항로의 기본제원 설계시, 대상 해역에서 예상되는 해상교통량을 그 접근 항로가 수용할 수 있는 능력이 있는지를 검토하기 위한 초기의 정량적 평가 수단으로 사용이 가능할 것으로 판단된다.

• 대한교통학회지
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• 제1권1호
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• pp.56-63
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• 1983

Intersection control has dual-purposes; increasing capacity and reducing delay. The primary concern of efficient intersection control under oversaturated condition as in Korea is to increase capacity. Prevailing intersection operation technique permits thru traffic to utilize left turn lane, because the intersection without left turn pocket has left turn signal interval. In this situation, it seems not to be valid to calculate capacity, delay, and signal timings by conventional methods. By critical lane technique, capacity increases as cycle length increases. However, when thru traffic utilize LT lane, the capacity varies according to LT volume, LT interval as well as cycle length, which implies that specific cycle length and LT interval exist to maximize capacity for given LT volume. The study is designed is designed to calculate utilization factors of LT lane for thru traffic and capacities, and identify signal timings to yield maximum capacity. The experimental design involved has 3 variables; 1)LT volumes at each approach(20-300 vph), 2)cycle lengths (60-220 sec), and 3)LT intervals(2.6-42 sec) for one scenario of isolated intersection crossing two 6-lanes streets. For LT volume of 50-150 vph, capacity calculated by using the utilization factor is about 25% higher than that by critical lane method. The range of optimum cycle length to yield maximum capapcity for LT volume less than 120 vph is 140-180 sec, and increases as LT volume increases. The optimum LT interval to yield maximum capacity is longer than the intrval necessary to accommodate LT volume at saturation flow rate.

• 대한산업공학회지
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• 제22권4호
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• pp.551-565
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• 1996

We present the required handover capacity of personal communication service exchange(PCX). We use the flow-based mobility model. The dimension of PCX area and the number of radio port controller(RPC) in a PCX are determined according to the traffic carrying capacity of switching system and RPC. For the rectangular or square-shaped PCX/RPC area and the personal communication service environment with pedestrian traffic, we perform numerical computations to investigate the sensitivity to cell size, portable station(PS) terminating traffic, its density, and its average speed. The results how that the size of PCX/RPC area decreases as the PS terminating traffic and the PS density increase, and the PCX handover capacity required is more than 73,000 in the number of transactions per hour.

• 해양환경안전학회지
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• 제24권4호
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• pp.381-388
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• 2018

본 연구에서는 선박의 속력을 고려한 해상교통량 평가 방법을 제안하였으며, 이를 선박의 속력을 고려하지 않은 기존의 방법과 비교하였다. 평가를 위하여 평택 당진항 10일간의 GICOMS 자료를 본 연구에 적용하였다. 그 결과 제안된 방법으로 평가된 환산교통량은 기존의 평가 방법에 비해 4.41(${\pm}0.99$)배 증가하거나, 0.59(${\pm}0.04$)배 감소하는 것으로 나타났다. 제안된 평가 방법을 적용한 각 시간대별 평균 해상교통혼잡도는 기존의 평가 방법 결과에 비해 1.43(${\pm}0.10$)배 높게 나타났으며, 각 시간대별 최대 해상교통혼잡도는 1.62(${\pm}0.34$)배 높게 나타났다. 해상교통혼잡도 최대 평가 결과인 피크타임 해상교통혼잡도는 선박의 속력 분포로 인하여 기존의 평가 방법과 다르게 평가됨을 확인하였다. 결과적으로 선박의 속력은 실용교통용량 평가 시 중요 값으로 적용되기 때문에 해상교통량을 평가할 때 선박의 속력을 고려하여야 할 것으로 사료된다.

• 한국항만학회지
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• 제8권2호
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• pp.1-35
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• 1994

The main arterial which runs through the in City of Pusan, carries about 60% of downtown traffic or more, maintains about 20% yearly increase in traffic is severely suffering from the traffic congestion because of concentrated traffic volumes regardless of peak-time periods. The purpose of this study was to grasp the traffic, geometric, and signal conditions of the main arterial through the Videologging System Techniques, perform the transportation system analyses, and finally suggest the improvements which could increase the travel capacity, reduce the average delay and fuel consumption with the optimal conditions of signal system. The following conclusions were drawn : firstly the traffic system should be shifted for the travel distribution on the arterial during the peak time periods, secondly the roadway system of the arterial reviewed for left-turn traffic during the peak time periods, and thirdly the signal system of intersection reconstructed for signal optimization or progression within the range of cycle length suggested.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2009년도 춘계학술대회
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• pp.891-894
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• 2009

In this paper, a scheme to evaluate the number of users in a WCDMA supporting multi-rate traffic is presented through the calculations of Erlang capacity from a derived blocking probability. It is observed that voice-data Erlang capacities have an inverse linear relationship. When the $E_b/N_o$ decreases from 4 dB to 3 dB within the outage probability of 2 % and at the voice rate of 8 kbps, the results show an increase of 8 Erlang at the data rates of 15 kbps, 4 Erlang at 30 kbps, 2 Erlang at 60 kbps, and 1 Erlang at 120 kbps respectively and an increase of the Erlang capacities through a gradual decrease of the data rates from 960 kbps to 15 kbps. So this is useful for optimizing as a reference of design for the capacity in a WCDMA system.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제3권2호
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• pp.251-257
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• 2003

In this paper, we wish to construct a optimal traffic cycle using wire remote control. if police vehicle or ambulance suddenly enter the traffic Intersection, it will increase the traffic accident. In this paper, wireless traffic light use the radio traffic control signal and research about the hardware manufacture to check special detectors on urgency vehicles may safety and rapidly enter traffic intersection. Also, this paper present a traffic signal control conditions that analyzes different traffic intersection flows in cases of saturated flows, where the real traffic volume demand is large and the capacity constraints of bottlenecks have significant effects on the flow patterns. Through computer simulation this wireless traffic light has been proven to be much more safety and efficient than fixed traffic signal light which does not consider emergency vehicles for safety escort.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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• pp.365-370
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• 2004

In this paper, we wish to construct a optimal traffic cycle using wire remote control. if police vehicle or ambulance suddenly enter the traffic intersection, it will increase the traffic accident. In this paper, wireless traffic light use the radio traffic control signal and research about the hardware manufacture to check special detectors on urgency vehicles may safety and rapidly enter traffic intersection. Also, this paper present a traffic signal control conditions that analyzes different traffic intersection flows in cases of saturated flows, where the real traffic volume demand is large and the capacity constraints of bottlenecks have significant effects on the flow patterns. Through computer simulation this wireless traffic light has been proven to be much more safety and efficient than fixed traffic signal light which does not considering emergency vehicles for safety escort.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 1998년도 추계학술대회논문집:21세기에 대비한 지능형 통합항만관리
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• pp.271-285
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• 1998

This paper aims to suggest the strategies for Korea port, especially Busan to develope into a viable transhipment center and/or Hub port as the articulation points between mainline and feeder nets. To tackle this goal, the authors clarify the requirements for Korea port which will be critical in determining its position as Hub through the careful analysis on competitiveness, environmental impact, port policy and capacity, transhipment traffic and inherent ablity to generate traffic. The results are summerized as follows. (1) Coping with increasing container volumes, new investment is sustainedly necessary to increase the capacity and inherent ability of container port and create economies of scale. Moreover, increasing port capacity will increase the potential for the Korea port's inclusion into mainline rather than feeder networks. (2) Considering an increasing awareness of need for customer-oriented option s and service quality rather than simply a reliance on infrastructure-led efficiency, privatization of one sort or another and corporation of port have been key strategies in achieving greater efficiency in Korea containerport.