• Journal of the Korean Operations Research and Management Science Society
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• v.34 no.1
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• pp.61-83
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• 2009

This study developed a variable demand traffic assignment model by stable dynamics. Stable dynamics, suggested by Nesterov and do Palma[19], is a new model which describes and provides a stable state of congestion in urban transportation networks. In comparison with the user equilibrium model, which is based on the arc travel time function in analyzing transportation networks, stable dynamics requires few parameters and is coincident with intuitions and observations on congestion. It is therefore expected to be a useful analysis tool for transportation planners. In this study, we generalize the stable dynamics into the model with variable demands. We suggest a three stage optimization model. In the first stage, we introduce critical travel times and dummy links and determine variable demands and link flows by applying an optimization problem to an extended network with the dummy links. Then we determine link travel times and path flows in the following stages. We present a numerical example of the application of the model to a given network.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.7-10
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• 1998

In implementing real time video on demand(VOD), the increase of user on internet causes a network traffic congestion. In this paper, we programmed a CGI able to login in VOD home for limiting the number of user in solving the problem, and also applied and adaptive multimedia synchronization technique for controlling video and audio data in a network. In addition, a real time multimedia player was designed and implemented in a personal computer operating at Window95/98/NT.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.149-150
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• 2012

According to the increase of demand of the deteriorated building. The interest of the building's maintenance is continually increased, so studies about how to increase building's stability & prolonged life span are increased. This study's purpose is to maintain building's function, so we suggest a protocol type system of UI to estimate reasonable planning of demand of repair & replacement and to distribute budget.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.30 no.3
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• pp.291-314
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• 2019

In this study, to improve the satisfaction of library users in the hospital and to examine how to activate the library in the future, the satisfaction of library, facilities and environment, staff, service, We conducted a demand survey and searched for the operation plan of the library that satisfied the user. As a result, in order to revitalize the library in the hospital, first, in the case of the collection, it is necessary to expand the number of collections of various topics with the latest contents. Second, it is urgent to expand the number of library staff in the hospital. In addition, it is necessary to improve communication expertise based on medical expertise and ability to respond quickly to user requests. Third, it is necessary to expand the size of library and convenience facilities in the hospital by facilities and environment. Fourth, in case of service, it is necessary to improve service quality and provide various services. Experts should provide subject search service, medical information source service, general health information service (patient and carer) according to the user. Finally, in the case of programs, it is necessary to expand the infrastructure for program operation, to diversify the targets, and to extend the program continuity.

• Journal of Korean Society of Transportation
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• v.19 no.1
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• pp.89-99
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• 2001

The conventional studies on equilibrium network design problem(ENDP) with fixed travel demand models assume that the future OD travel demand might not be changed even if the structure and the capacity of the network are improved. But this fixed demand assumption may loose its validity in the long-range network design because OD travel demand actually shifts with the network service level. Thus, it is desirable to involve the variable travel demand which is determined endogenously in the model in the optimal network design. In this paper a hi-level model formulation and solution procedure for ENDP with variable travel demand are presented. Firstly It is considered how to measure the net user benefits to be derived from the improved in link capacities, and the equilibrium network design problem considered here is to maximize the increase of net user benefit which results from a set of lift capacity enhancements within the budget constraints, while the OD travel demands and link travel times are obtained by solving the lower level network equilibrium problem with variable demand. And secondly sensitivity analysis is carried out to find the links to which the network equilibrium flow pattern is the most sensitive. Finally numerical example with simple network is carried out to test the validity of the model.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2002.05a
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• pp.152-155
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• 2002

In recent years, with the spread of communication media, such as a cellular phone and E-mail, we are able to communicate with others without any restriction of position or time. However, complexity of communicative context has increased so that user has to guess a partner user's situation and status in order to use various medias efficiently. This problem will grow larger as new media are brought in the expanding communications network. To solve this problem, we propose the system that guesses the context in communication by a user's media from the position information on PHS (Personal Handy phone System) and schedule information from schedule application. In this system a user's agent guesses automatically the context that owner has set, and answers the demand of the context from a partner user. Moreover, the agent decides a suitable answer, when there is a demand of communication by the media, which cannot be used.

• Journal of the Korea Society for Simulation
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• v.15 no.3
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• pp.11-21
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• 2006

Importance of and need for grid resource management have accelerated in accordance with increasing development of grid computing. However, it is very complex to distribute and utilize resources efficiently in geographically dispersed environments. This is due to the different access policies and constraints of grid resource owners. Users request resources according to their needs. Operators of a grid computing system need to be able to monitor the system states for reflecting these demands. So, a grid computing system needs a resource management policy that monitors states of resources and then allocates resources. This paper proposes a user demand-based grid trade management model that provides an efficient resource management by the trade allocation based on a users' demand and providers' supply strategy. To evaluate performance, this paper measures increasing rate of resource trades, average response time of trades, and processing time utilization. Firstly, the average increasing rates of trade are 585.7% and 322.6% higher than an auction model and a double auction model. Secondly, the average response time of the user demand-based grid trade management model is maintained between 3 and 5 simulation time. Finally, it is found that the processing time utilization is an average of 145.4% and 118.0% higher than an auction model and a double auction model. These empirical results demonstrate the usefulness of the user demand-based grid trade management model.

• the USERS
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• s.47
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• pp.58-59
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• 2006

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.26 no.4
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• pp.105-121
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• 2015

PDA model is new collection development method not only corresponding user's demand, but also expensing acquisition budget effectively. In the PDA model, when the trigger that indicates user's demand reaches up to treshold, e-book is automatically purchased without librarian's interrogation. This study examines concept, basic principles, and current condition of operation about PDA and finds a way that could applicate to Korean university library foreign E-book consortium. Current model of university library e-book acquisition pursuit reduction of budget and utility value, but the selected collection is not based on user's demand. Therefore, it could be considerable to apply PDA or evidence based purchase model to foreign e-book acquisition consortium.

• Journal of the Korean Institute of Landscape Architecture
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• v.27 no.4
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• pp.122-130
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• 1999

The main purpose of this project is to improve the funeral and grave culture which has brought about many social problems, and to fix the crematory culture as the future funeral ceremony in our country. In this study, we first investigated the actual condition of cremation culture. Second, we survey three representative crematorium as an object of study and investigated similar sample buildings in Japan, we analyzed the problem of existing crematorium. Finally, we arranged the basics to approach the space program and design criteria of this project. 1. The entrance of vehicles has been commonly concentrated to the opening time of crematorium. therefore, Peak time has come out as circulation of cremation and waiting time is increasing, also it is difficult to manage the congestion normally. 2. The whole problem of crematorium is poor environment, inferior buildings, noise, unsatisfactory ventilation and privacy, insufficient convenience facilities. 3. The user demand on the crematorium facilities is a private family room for waiting area, a farewell room for family members in a direct line, an outdoor rest area, and the various service facilities, and so on. 4. For improvement of the funeral and grave culture, it is necessary that crematorium is not a hatred facilities, as the conversion of consciousness, and to new shape of charnel as it wore family tomb.