• Journal of Korean Society of Transportation
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• v.2 no.1
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• pp.33-68
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• 1984

수요감응교통체계는 승객들의 통행요구에 따라 보다 신속하고 효율적으로 안락하고 편리하게 경제적으로 교통서비스를 제공하는 것이다. 특히 기존의 공공교통수단이 미치지 못하는 저밀도 도시 지역의 통행수요를 만족시키는데 좋은 수단으로써 관심의 대상이 되고 있다. 즉 리무진 같은 소형차량을 이용하여 승객의 통행요청에 따라 개인적인 door-to-door 서비스를 제공하는 것이다. 본연구는 수요감응교통체계의 대안으로서 도시 서비스에 있어서 고정.노선변경승객 써비스에 대한 $\ulcorner$스케쥴 알고리즘$\lrcorner$을 개발하는데 목표를 둔바 목적함 수는 Waiting time, Riding time,Scheduled vehicle의 노선용량제한등과 같은 승객써비스 시 간제약에 대해서 각기 개별차량 여행과의 차를 극대화하여 보았다. 사용자중심 Sub-program과 PASS의 두 Sub-program으로 구성된 Simulation 모형을 활용할 경우 어떠 한 도시 써비스지역에서의 고정노선 혹은 변경노선 각각에 대해서 임시적인 차량운행의 감 응식 효율 증진에 크게 기여할 수 있는 것으로 나타났다.

• Proceedings of the IEEK Conference
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• 2002.07b
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• pp.1074-1077
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• 2002

This paper proposes an adaptive pricing system with scheduling to balance the demand for contents and to realize an effective use of resources in contents delivery networks. In the proposed adaptive pricing system, the table of the service levels and prices (tariff) is shown to each user at the start of service and each user chooses one of the service classes. These prices are decided adaptively reflecting the congestion state of the networks. Then, by the proposed scheduling algorithm, these requests are scheduled so as to keep the service level agreements completely.

• Journal of Forest and Environmental Science
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• v.24 no.3
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• pp.171-174
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• 2008

The increasing price of liquefied petroleum gas (LPG) has forced many households to shift to firewood/charcoal in the Philippines, causing tremendous pressure on the dwindling forest. This transition is more obvious in the rural area where firewood price is almost half of that in the cities. Both problems on big demand for firewood and the pressure on our forest can be partly solved by going into firewood plantation. After all, the country has vast track of idle lands, both private and government lands, waiting to be developed. What the government can do are: a) aggressive promotion of firewood plantation, b) simplify further the old technology on establishing firewood plantation to encourage more farmers, c) improve charcoal processing and d) promote the use of efficient stoves. This write up discusses the need for firewood plantation, areas available for planting, where to plant in farms, what species to plant in a particular soil type/location for optimum growth, planting methods, harvesting, marketing, and the side lights on the ecological benefits derived from plantation aside from wood.

• Journal of the Korean Operations Research and Management Science Society
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• v.37 no.2
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• pp.31-43
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• 2012

Delivery of a good quality of service in an efficient manner requires matching the supply of capacity with customer demand. Much research has employed queueing models that analyzed the service system on the basis of independent and stationary customer arrivals. However, the appointment system, which is widely used to facilitate customer access to service in many industries including healthcare, has significant influence on the customer arrival process so that the independent and stationary assumption does not hold in an appointment-based service system. In this regard, this paper aims to propose a model for accurate illustration of the appointment-based customer arrival process. The use of the proposed model allows us to evaluate the overall system performance such as mean waiting time and service level under various appointment policies instead of conducting simulation studies.

• Journal of the Korean Operations Research and Management Science Society
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• v.23 no.3
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• pp.153-168
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• 1998

In this study we consider a CONWIP system in which the processing times at each station follow an exponential distribution and the demands for the finished Products arrive according to a compound Poisson process. The demands that are not satisfied instantaneously are assumed to be backordered. For this system we develop an approximation method to obtain the performance measures such as steady state probabilities of the number of parts at each station, the proportion of backordered demands, the average number of backordered demands and the mean waiting time of a backordered demand. For the analysis of the proposed CONWIP system, we model the CONWIP system as a closed queueing network with a synchronization station and analyze the closed queueing network using a product form approximation method. A matrix geometric method is used to solve the subnetwork in the application of the product-form approximation method. To test the accuracy of the approximation method, the results obtained from the approximation method were compared with those obtained by simulation. Comparisons with simulation have shown that the approximate method provides fairly good results.

• Journal of the Korean Society for Railway
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• v.6 no.1
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• pp.73-79
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• 2003

The Korean high speed railroad is scheduled to open in 2004. For railroad-based integrated transfer system, it is essential to develop the intermodal information system for easy transfer to other travel modes. The understanding of mode choices by KTX passengers is crucial for the intermodal transportation planning. Recent development of Intelligent Transportation Systems(ITS) made it possible for railroad users to access the transportation information in a cabin or waiting areas at the station. Development of intermodal transportation information system will influence the relative demand for traveling by train from competing other transportation modes. The research is focused on a general overview of the ITS with an emphasis on intermodal transportation information system.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.133-138
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• 2003

The Korean high speed railway is scheduled to open in 2004. For railway-based integrated transfer system, it is essential to develop intermodal information system for easy and better transfer to other travel modes. An understanding of mode choices by KTX passengers is crucial for the intermodal transportation planning. Recent development of Intelligent Transportation System made it possible for railroad users to access the information in a cabin or waiting areas at the station. Development of intermodal transportation information system will influence the relative demand for traveling by train from competing other transportation mode. The research is focused on a general overview of the ITS with an emphasis on intermodal transportation information system.

• Journal of The Korea Institute of Healthcare Architecture
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• v.6 no.10
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• pp.67-76
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• 2000

Hospital architecture is in a transitional period and faces a great change. Furthermore, patients' demand on medical service has been changing. It is said that the importance of public space for people as well as that of private space for patients, doctors and nurses becomes more important than ever. For example, corridor space becomes pathway, waiting room and rest area of patients. Accordingly, the importance of corridor space of public space in general hospitals is increasing. This study aims to present standard data for hospital planning by analyzing space allocation and floor area of corridor space in general hospitals.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.412-418
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• 2013

With the increasing demand for public housing, the Singapore government decided to reduce the waiting time of future public housing owners, which requires these projects to be completed on time. As a result, this study aims to identify the frequent and impactful factors affecting schedule performance of public housing projects in Singapore. The survey conducted with 36 industry experts revealed that "site management", "coordination among various parties", "design changes by owner during construction", "availability of laborers on site", "availability of material", and "availability of staff to manage projects" were the six factors that should be emphasized to assure the schedule performance of public housing projects. In addition, there was statistically significant agreement between public housing projects and other building projects on both the frequency and impact ranks of the factors. The findings from this study will help practitioners involving public housing projects to take measures to assure the achievement of project schedule objectives.

• Journal of KIISE:Databases
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• v.32 no.4
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• pp.394-404
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• 2005

Battery capacity of mobile clients in wireless mobile computing environments is one of the important resources that determine the availability of mobile clients. So, data broadcast techniques in mobile computing environments need not only rapid delivery of requested data but also efficient data delivery mechanisms which can reduce battery consumption of mobile clients. This paper proposes organization of an index and broadcast data for on-demand data broadcast. It organizes an index containing broadcast time of each data using some of high-priority data in a broadcast server. By sending such index information prior to the corresponding data, the proposed approach reduces tuning time of mobile clients. It also includes when the next index information will be broadcasted in each data broadcast. This can reduce tuning time of mobile clients waiting for an index to be broadcasted. Experiments show that the proposed approach effectively reduces tuning time of mobile clients.