• 센서학회지
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• 제17권3호
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• pp.236-244
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• 2008

The Korean government is building several futuristic cities, ubiquitous City (u-City), with the latest information technology (IT) infrastructure and "ubiquitous" environment. In the "u-City", Intelligent Transportation System (ITS) will be one of the important services. This study proposed a traffic responsive urban traffic control system applicable in those u-City, using RFID (Radio Frequency Identification) technology to get traffic information. And, we proposed a predictive control model using the real time traffic information achieved from the proposed system. A simulation example is provided to demonstrate the applicability of the proposed system and model.

• 한국통신학회논문지
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• 제31권12A호
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• pp.1246-1252
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• 2006

본 논문에서는 random FHSS, synchronous FHSS 방식을 채용한 RFID 시스템의 충돌 확률, 트래픽 처리시간 및 주파수 채널 용량 분석을 위한 알고리즘을 제시하였다. 평균 서비스 시간, duty cycle, traffic intensity, 충돌이 발생하여 재전송 시도를 하기 위한 지연시간을 고려하여 정상상태에서의 충돌 확률 및 트래픽 처리 지연시간을 산출하였다. 모의실험을 통하여 최대처리 가능한 트래픽 용량 및 주파수 채널수를 평가하고, 제안된 분석 알고리즘 정확성을 입증하였다.

• 경영과학
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• 제10권1호
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• pp.107-125
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• 1993

Modern telecommunication switching systems are SPC(Stored Program Control) machines handling voice, data and other kinds of traffic, in an environment which tends to be fully digital switching and transmission. The throughput of such systems is determined by the real time capacity of its centralized or distributed control processors and by the traffic capacity of the switching network. Designers must verify the traffic and call processing capacity of the switching system and check its performance under traffic load before it is put into service. Verification of traffic and call processing capacity of switching systems is one of the problems treated by teletraffic studies ; teletraffic studies are based on stochastic process, queueing theory, simulations and other quantitative methods of decision making. This study suggests the general methodology to evaluate the throughput and performance of the ISDN switching system. TDX-10 ISDN switching system are employed to give illustrative examples of the methodologies discussed in this study.

• 대한산업공학회지
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• 제13권2호
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• pp.17-34
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• 1987

Modern telecommunication switching systems are SPC (Stored Program Control) machines handling voice, data and other kinds of traffic, in an environment which tends to be fully digital switching and transmission. The throughput of such systems is determined by the real time capacity of its centralized or distributed control processors and by the traffic capacity of the switching network. Designers must verify the traffic and call processing capacity of the switching system and check its performance under traffic load before it is put into service. Verification of traffic and call processing capacity of switching systems is one of the problems treated by teletraffic studies; teletraffic studies are based on stochastic process, queueing theory, simulations and other quantitative methods of decision making. This paper reviews the general methodologies to evaluate the throughput and performance of the digital switching system. TDX-10, which is a fully digital switching system under development in ETRI, is employed to give illustrative examples of the methodologies discussed in this paper.

• 산업경영시스템학회지
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• 제20권43호
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• pp.91-97
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• 1997

The objective of a traffic management system is to promote safe driving, low pollution, short travel time, and optimized traffic flow by naturally distributing the flow of traffic through the use of suitable telecommunications media. Such traffic management systems will be improved by integrating dynamic traffic data and two-way communication media because cars can work as sensors. The purpose of this paper is to help organizations trying to select the correct telecommunications media for minimal-cost investment options without loss of functionality. The wireless communications for an intelligent transportation system (ITS) are introduced in this paper. We describe which kind of telecommunication media are suitable. FM broadcast type media or cellular phone can be recommended to provide real time traffic and roadway conditions in the first stage of ITS, because existing broadcast base station or cellular network facilities can be used. It is expected that cellular radio network or satellites are used for communication. Finally, the strategy and deployment plan of an ITS are described based on selections of telecommunication media in Korea.

• ETRI Journal
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• 제44권2호
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• pp.194-207
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• 2022

In the last decade, substantial progress has been achieved in intelligent traffic control technologies to overcome consistent difficulties of traffic congestion and its adverse effect on smart cities. Edge computing is one such advanced progress facilitating real-time data transmission among vehicles and roadside units to mitigate congestion. An edge computing-based deep reinforcement learning system is demonstrated in this study that appropriately designs a multiobjective reward function for optimizing different objectives. The system seeks to overcome the challenge of evaluating actions with a simple numerical reward. The selection of reward functions has a significant impact on agents' ability to acquire the ideal behavior for managing multiple traffic signals in a large-scale road network. To ascertain effective reward functions, the agent is trained withusing the proximal policy optimization method in several deep neural network models, including the state-of-the-art transformer network. The system is verified using both hypothetical scenarios and real-world traffic maps. The comprehensive simulation outcomes demonstrate the potency of the suggested reward functions.

• 한국도로학회논문집
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• 제15권1호
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• pp.163-169
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• 2013

PURPOSES: The urban traffic problems can be defined as general problems for smooth traffic flow including maintenance of mass transportation system according to suddenly increased population, traffic regulations for vehicles and pollution problem. As a method for solving traffic jams, one of the traffic problems of late, interest in Intelligent Traffic System(ITS) is increasing sharply, which is a system managing traffic demand by providing passers with information on traffic state of path and road conditions before they pass the road through ATIS, a field of ITS. METHODS: Variable message signs(VMS) is used on the roads as a method for providing information to promote smooth traffic flow and safety and prevent traffic accidents in advance by providing drivers with various information while driving. RESULTS: Recently, as ITS industry has been vitalized and technical factors of VMS have developed, various kinds of information is provided but the effect of VMS has not been maximized due to its limited type. CONCLUSIONS: Therefore, this study intends to provide methods for effective information transfer by analyzing driver's visual behavior characteristics for VMS and presenting a basis for maximizing VMS effect after considering read by expression type.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 추계학술대회 논문집(제1권)
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• pp.127-132
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• 2006

해상교통량 조사 분석은 안전하고 원활한 항로 항만의 설계와 제반시설의 개선 및 항행관리를 위하여 반드시 필요한 수단이다. 해상교통량 조사 분석과정에서 정확한 조사방법을 통해 선박통항에 관한 데이터들을 수집하여야 하고, 수집된 선박교통량에 관한 다양한 정보는 정확하고 과학적으로 분석되어야 한다. 이 논문에서는, 해상교통량 조사과정에 있어 인력에 의해 일어날 수 있는 오차를 보완할 수 있으며, 정확한 조사의 실행 및 분석결과를 출력할 수 있는 시스템을 연구 제작함을 목표로 한다. AIS 및 전자해도를 기반으로 하여 정확하고 신속하게 선박교통정보를 수집하여 조사분석자의 수고를 경감시켜줄 수 있으며 표준화된 분석결과를 제시해줄 수 있는 해상교통량 분석 시스템을 제안하고 그 개발 내용을 소개하고자 한다.

• 한국심리학회지 : 문화 및 사회문제
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• 제16권3호
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• pp.267-287
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• 2010

본 연구는 우리나라의 교통사고 조사양식을 개선하고 이를 통해 사고조사 자료의 신뢰성을 확보하여 인적 사고관련 요인 판단에 도움을 줄 수 있는 방안을 모색하기 위해 실시되었다. 먼저 교통사고 조사양식 개선안을 만들기 위해 미국과 영국에서 사용하고 있는 조사양식 및 관련 연구들이 제시한 항목들을 분석하였다. 또, 이렇게 만들어진 조사양식 개선안이 충분한 사고설명력을 가지는지 알아보기 위해 2008년 한 해 동안 경기도에서 발생한 사망사고 중 502건을 새로 분석하여 기존 항목에 의한 분석결과와 비교하였다. 분석결과, 도로환경 부문과 운전자 요인 부문에서 일부 불명확한 내용의 기존항목이 제거되고, 새로운 내용들이 사고조사 양식에 반영되어야 할 필요성이 제기되었다. 본 연구결과를 바탕으로 인적요인을 고려한 교통사고 조사양식 개선안과 추후 연구과제들을 논의와 부록자료를 통해 제안하였다.

• 대한전자공학회논문지TC
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• 제45권2호
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• pp.26-36
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• 2008

현재 우리나라에는 최첨단의 정보통신 서비스를 제공을 목적으로 ubiquitous city(u-City)가 건설 중에 있다. 이들 도시에서 ITS(Intelligent Transportation Systems)는 도시거주민들에게 적절한 교통정보를 제공하는 동시에 최적으로 도시교통을 제어하는 방안이다. ITS의 한 부분으로서 교통흐름에 적합한 교통신호제어가 필요하며 이를 위해 많은 교통정보를 실시간으로 수집하여야 한다. 이러한 교통정보의 수집은 도시운영을 위하여 최첨단 정보통신 서비스가 제공되는 u-City에서는 어렵지 않을 것이다. 이러한 미래지향적인u-City의 ITS 교통제어에 적합한 새로운 시스템에 대하여 이 논문에서는 연구하였다.