• Spatial Information Research
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• 제19권4호
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• pp.11-20
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• 2011

저탄소 녹색성장 패러다임에 맞춰 지하철은 대중교통 활성화를 위한 도시 교통의 핵심 운송 수단이다. 지하철은 대량 수송 교통체증완화 교통사고 감소 등의 역할 뿐 아니라 노선 확장에 따라 도시 공간과 네트워크상의 승객 수요의 변화를 촉진시킨다. 현재 수요예측을 주축으로 노선계획이 이루어지고 있어, 지하철 노선 변화에 따른 교통 접근성과 승객 수요 변화를 위한 실증적인 연구가 미비하다. 이에 본 연구의 목적은 공간구문론을 이용한 사전사후 분석을 통해 지하철 개통에 따른 대중교통 영향성을 네트워크의 연결성, 승객 이동성 측면에서 정량적으로 예측 할 수 있는 대안적 평가 방법론을 제시하는 것이다. 우선 2009년 개통된 서울시 지하철 9호 선을 중심으로 도시 철도 네트워크를 구축하고, 공간 구문 모델을 통해 9호선이 개통됨에 따른 네트워크의 위상적 변화 패턴을 분석하였다. 또한, 모델 측정 결과를 검증하기위해, 서울시 교통 카드시스템의 역간 지하철 승차 인원수와 버스 노선별 승차 인원수 자료를 이용하여, 경쟁 노선을 대상으로 버스 이용객의 수단 전환과 주요 환승역에서 승객 수요 변화를 분석하였다. 결론적으로 본 연구 방법론을 통해 지하철 노선 계획에 있어 승객수요변화를 가시화하고 노선 추가에 따른 전후 시공간적 변화 분석이 가능하였으며 향후 주변 대중교통의 영향성과 실제 대중교통 이용자의 이동패턴에 대한 효과적인 공간적 변화 분석에 활용될 것으로 기대한다.

• 산업공학
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• 제15권4호
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• pp.474-482
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• 2002

In this paper, we propose a parametric optimization approach to simultaneously determining trip distribution, mode choice, and user-equilibrium assignment. In our model, mode choice decisions are based on a binomial logit model and passenger and cargo demands are divided into appropriate mode according to the user equilibrium minimum travel time. Underlying network consists of road and rail networks combined and mode choice available is auto, bus, truck, passenger rail, and cargo rail. We provide an equivalent convex optimization problem formulation and efficient algorithm for solving this problem. The proposed algorithm was applied to a large scale network examples derived from the National Intermodal Transportation Plan (2000-2019).

• 산업경영시스템학회지
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• 제28권4호
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• pp.134-141
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• 2005

Due to the complexity and stochastic nature of automated warehousing system, items are usually queued up at I/O point. We introduce a storage/retrieval policy : dual-command. We present quick approximations to queueing phenomena under these policies. It is assumed that the storage and retrieval arrival pattern follow the same poisson process. We also assumed that storage queue and retrieval queue being operated separately. The approximation attempts are performed under the proposed storage/retrieval policies after we derive S/R machine travel time distributions.

• 대한임베디드공학회논문지
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• 제9권4호
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• pp.229-235
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• 2014

This paper presents an environmental navigation system which provides a guidance to the users of smart bicycle for a pollution-free route during their travel. The smart bicycle operates as a sensor node being composed of a distributed wireless sensor network over the whole urban area. Several environmental sensors measuring the amount of dust, CO, $CO_2$, $NO_2$ in the air are built into the smart bicycle to estimate the level of air pollution in the located area. Each smart bicycle sends/receives the measured sensor data and the city pollution map to/from the centralized server, which leads the bike-riders to a healthy route by providing the environmental navigation information. The proposed idea and its implementation give a useful insight on various application services with the distributed smart bicycles.

• 산업경영시스템학회지
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• 제24권62호
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• pp.97-109
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• 2001

This research is concerned with jobshop scheduling problem for an advanced manufacturing system like flexible manufacturing which consists of two machine centers and a single automated guided vehicle(AGV). The objective is to develop and evaluate heuristic scheduling procedures that minimize makespan to be included travel time of AGV. A new heuristic algorithm is proposed and illustrates the proposed algorithm. The heuristic algorithm is implemented for various cases by SLAM II. The results show that the proposed algorithm provides better solutions in reduction ratio and frequency than the previous algorithm.

• 대한산업공학회지
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• 제27권2호
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• pp.140-149
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• 2001

The paper discusses the problem of finding the Origin-Destination(O-D) shortest paths in internodal transportation networks with time-schedule constraints. The shortest path problem on the internodal transportation network is concerned with finding a path with minimum distance, time, or cost from an origin to a destination using all possible transportation modalities. The time-schedule constraint requires that the departure time to travel from a transfer station to another node takes place only at one of pre-specified departure times. The scheduled departure times at the transfer station are the times when the passengers are allowed to leave the station to another node using the relative transportation modality. Therefore, the total time of a path in an internodal transportation network subject to time-schedule constraints includes traveling time and transfer waiting time. In this paper, a genetic algorithm (GA) approach is developed to deal with this problem. The effectiveness of the GA approach is evaluated using several test problems.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1988년도 한국자동제어학술회의논문집(국제학술편); 한국전력공사연수원, 서울; 21-22 Oct. 1988
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• pp.810-815
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• 1988

This paper presents a mobile robot that travels employing visual information. The mobile robot is equipped solely with a TV camera as a sensor, and views from the TV camera are transferred to a separately installed micro computer through an image acquisition device. An acquired image of a view is processed there and the information necessary for travel is yielded. Instructions based on the information are then sent from the micro computer to the mobile robot, which causes the mobile robot next action. Among several application programs that have already been developed for the mobile robot other than the entire control program, this paper focuses its attention on the travelling control of the mobile robot in a model environment with obstructions as well as an overview of the whole system. The behaviour the present mobile robot takes when it travels among obstructions was investigated by an experiment, and satisfactory results were obtained.

• 대한안전경영과학회지
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• 제14권2호
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• pp.23-33
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• 2012

Recent technological advances in the domestic railway industry have turned out to deliver a profound impact on the forefront of other industries as well. Furthermore, the introduction of the high-speed railway systems has made it possible to travel around our country in a day, thereby changing our life styles a lot. However, it has been well recognized that many factors can cause unanticipated accidents during the operation. One of the causes is known to be the human errors made by the train operators in locomotive cabs. The problem is getting more serious as the trains run at high speed. As such, the objective of this paper is on how to improve the work environment of the locomotive cabs. Our approach is based on the systems engineering methodology. Specifically, we first identify the context and scope of the problem to be solved. We then continue our effort in deriving the requirements set to accomplish the improvement. These results are utilized in constructing a computer-aided management system for test and evaluation intended for the improvement. The approach taken and the results obtained in this paper is expected to make a contribution on the route to keeping our nation's technologies on the competitive edges in the high-speed railway systems industry.

• 제어로봇시스템학회논문지
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• 제10권11호
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• pp.1052-1057
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• 2004

Bluetooth technology is essentially a method for wireless connectivity of a diverse set of devices ranging from PDAs, mobile phone, notebook computers, to another equipments, The bluetooth system both point-to point connection and point-to multipoint connection. In point-to multipoint connection, the channel is shared among several bluetooth devices. Two or more devices sharing the same channel form a piconet. There one master device and up to seven active slave devices in a piconet. The radio operates in the unlicensed 2.45GHz ISM band. This allows users who travel world-wide to use bluetooth equipments anywhere. Since the link is based on frequency-hop spread spectrum, multiple channels can exist at the same time. The bluetooth standard ha s been suggested that bluetooth equipments can be used in the short-range, maximum 100 meters. It has been defined that the time takes to setup and establish a bluetooth connection among devices is 10 seconds. It is a long time and may be a cause to lose a chance of finding other non-fixed devices. We propose a routing protocols for scatternets which can be used to control a mobile units(MUs) in this network. The proposed routing protocol is composed of two kinds of bluetooth information, access point(AP) and MU.

• 대한교통학회지
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• 제13권1호
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• pp.185-203
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• 1995

The purpose of this paper is to develop a microscopic traffic simulation model which is able to both analyze and the evaluate signlaized urban network and to verify its usefulness in comparison with the other model which has alfeady been released. This simulation model adopts the General Motor's 5th model for car-following and introduces an unique lanechanging rule using acceptable gap. It analyzes single and dual-ring signal phases and generates detector information . So it could be applied to dynamic route guidance systems as wel as real time signal control systems. The results derived from Netsim and the observed data from the real network have been used to test the validit of the proposed model. The result of the test has shown that there are no significant differences between the NETSIM model and the proposed model in estimating travel speed and stopped delay. In optimum offset estimatin , it has shown the same results with NETSIM. the measure of effectiveness , however, derived from this model is slightly better than that of the real network situation. This may be due to the fact that the proposed model does not take into account side frictions from interferences and obstacles.