• Water for future
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• v.28 no.6
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• pp.217-228
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• 1995

For optimal reservoir operation during flood period, a general and systematic policy is suggested to make balance of the conflicting purposes between water conservation and flood control. The purpose of this study is to decide the restricted water level of the reservoir during flood period specially to meet water demand in non-flood period. The optimal policy is derived by reallocation of storage capacity through the application of variable restricted water level(VRWL) and minimum required water level(MRWL) for shorter intervals. This study also suggests water level dconditions to secure conservation storage capacity at the end of the flood period estimated by reservoir operation study. This paper illustrates an application of the Daecheong Dam and Chungju Dam respectively during flood and the results are reviewed.

• Journal of the Economic Geographical Society of Korea
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• v.16 no.1
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• pp.135-148
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• 2013

This paper attempts to explain the energy policy to respond to climate change that is debated in recent years. Especially by the case of Germany among developed countries, the study investigates the direction, strategy and measure of energy policy which are implemented at the national level. The Energy policy of Germany revealed through this study will provide implications for the establishment and propulsion of the energy policy trying to overcome the crisis of energy resources and reduce greenhouse gas emissions. Firstly, this study reviews Germany's supply and consumption of energy and trends of greenhouse gas emission, and secondly discusses the process of the historical development of Germany's energy policy.

• Korean Journal of Construction Engineering and Management
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• v.23 no.2
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• pp.24-32
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• 2022

In Korea, the productivity of the construction industry is evaluated at a very low level, and the utilization of the elemental technology of the Fourth Industrial Revolution is also very low compared to other industries. In order to solve this problematic situation, it is necessary to identify the demand for technology improvement in the specialty construction industry that is directly in charge of construction in projects. Therefore, this study aims to investigate improving construction competitiveness and the demand for technology improvement in Korea's specialty construction industry. First, the concept and status of classification of the specialized construction industry were identified, and a questionnaire was organized. Second, a survey was conducted on experts construction experts, and the demand for technical improvement of the specialty construction industry was derived by applying AHP and cluster analysis. The results of this study will serve as a practical reference for policy development, R&D direction, and technology development roadmap to enhance construction competitiveness in the future, and ultimately will help to present directions to improve the construction competitiveness of the construction industry.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.42
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• pp.21-30
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• 1997

This research fundamentally deals with an analysis of service level for a multi-level inventory distribution system which is consisted of a central distribution center and several branches being supplied stocks from the distribution center, Under continuous review policy, the distribution center places an order for planned order quantity to an outside supplier, and the order quantity is received after a certain lead time. Also, each branch places an order for particular quantity to its distribution center, and receives the order quantity after a lead time. In most practical distribution environment, demands and lead times are generally not fixed or constant, but variable. And these variabilities make the analysis more complicated. Thus, the main objective of this research is to suggest a method to compute the service level at each depot, that is, the distribution center and each branch with variable demands and variable lead times. Further, the model will give an idea to keep the proper level of safety stocks that can attain effective or expected service level for each depot.

• Journal of the Korea Safety Management & Science
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• v.3 no.3
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• pp.65-75
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• 2001

This research fundamentally deals with an analysis of service level for a multi-level inventory distribution system which is consisted of a central distribution center and several branches being supplied stocks from the distribution center, Under continuous review policy, the distribution center places an order for planned order quantity to an outside supplier, and the order quantity is received after a certain lead time. Also, each branch places an order for particular quantity to its distribution center, and receives the order quantity after a lead time. In most practical distribution environment, demands and lead times are generally not fixed or constant, but variable. And these variabilities make the analysis more complicated. Thus, the main objective of this research is to suggest a method to compute the service level at each depot, that is, the distribution center and each branch with variable demands and variable lead times. Further, the model will give an idea to keep the proper level of safety stocks that can attain effective or expected service level for each depot.

• Journal of Information Technology Services
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• v.19 no.2
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• pp.125-138
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• 2020

Currently, subway crowding is estimated by observing a specific point at specific hours once or twice every 1 or 2 years. Given the extensive subway network in Seoul Metropolitan Area covering 588 stations, 11 lines and 80 transfer stations as of 2017, implementing crowding mitigation policy may have its limitations due to data uncertainty. A proposal has recently been made to effectively use smart card data, which generates big data on the overall subway traffic related to an estimated 8 million passengers per day. To mitigate subway crowding, this study proposes two viable options based on data related to smart card used in Seoul Metropolitan Area. One is to create a subway passenger pattern model to accurately estimate subway crowding, while the other is to prove effectiveness of early bird policy to distribute subway demand that is concentrated at certain stations and certain time. A subway passenger pattern model was created to estimate the passenger routes based on subway terminal ID at the entrance and exit and data by hours. To that end, we propose assigning passengers at the routes similar to the shortest routes based on an assumption that passengers choose the fastest routes. In the model, passenger flow is simulated every minute, and subway crowding level by station and line at every hour is analyzed while station usage pattern is identified by depending on passenger paths. For early bird policy, highly crowded stations will be categorized based on congestion level extracted from subway passenger pattern model and viability of a policy which transfers certain traveling demands to early commuting hours in those stations will be reviewed. In particular, review will be conducted on the impact of policy implemented at certain stations on other stations and lines from subway network as a whole. Lastly, we proposed that smart card based subway passenger pattern model established through this study used in decision making process to ensure effective implementation of public transport policy.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.41 no.4
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• pp.1-10
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• 2004

In NGNs(Next Generation Networks), It is necessary for Integrated management of resource and information to satisfy high-quality users'demands, such as stable speed, guarantee of high level service and service requirement in various fields. In relation to this, technology for efficiently using limited resources is becoming interesting things more and more. Therefore policy of network service is dealt essentially. Recently, DEN(Directory Enabled Network)-based personalization service is user-dependent services in NGNs, and integrated management and efficient use of limited resources. Also, PBNM(Policy-Based Network Management) is new technology defined and applied by policies of communication service environments and users on demand. Subsequently to study on how to optimizing the PBNM is of great importance. In this paper, we propose a technology of the PBNM based on DEN standardized in DMTF(Distributed Management Task Force).

• Journal of Families and Better Life
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• v.5 no.2
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• pp.65-82
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• 1987

Product characteristic approach and hedonic method were explained and applied to demand behavior of housing for 360 households sampled from four districts of Seoul. Th major findings are: 1) Housing prices are determined by housing characteristics, i.e., basic structure, interior space, interior quality, and neighborhood quality. 2) as income increase , the demand for basic structure, interior space, interior of quality, and neighbor hood quality increases. As compared to the counties that have advanced housing financial systems, income elasticity form housing characteristics was low. 3) householder's educational level has insignificant effects on the demand for neighborhood quality. 4) the housing need of family is different to a family life cycle. In the first stage, the increase of income enhances the demand for basic structure. interior space, and interior quality, but inversed with neighborhood quality. In the second and third stages, the demand for basic structure, interior space, and interior quality increases as the income increases. 5) It is predicted that the larger the family size, the more housing space is required. But in the low-income group, an increase in family size results in a decrease in the demand for interior space because expenses for food and education are indispensable ones. In the middle -income group the demand for interior space, interior quality increases as the family size increases, In the high-income group, the larger the family size the more interior quality is demanded. As mentioned above, the demand for housing is derived form characteristics and the demand behavior far housing characteristics is varied with individual household's characteristics. Therefore, the fact that different housing needs according to various income groups should be considered in housing policy.

• Journal of the Korean Operations Research and Management Science Society
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• v.33 no.2
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• pp.137-151
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• 2008

This paper deals with two shops dealing with single perishable product the fresh items are sold at a list price in the primary shop and the unsold items that have reached a certain allowed age are transferred to the secondary shop to be sold at a discounted price. It is assumed that the demand rates in two shops are Independent each other and can be expressed as a function of inventory level and price. With the objective of maximizing the profit under a Last-In-first-Out. (LIFO) issuing policy, we develop mathematical models for the following two cases : (1) opening primary shop only and (2) opening both primary shop and secondary shop. There are three decision variables, i.e., the reduced price in the secondary shop, the allowed age at the primary shop, and the order quantities at the primary shop. A solution procedure is developed based on tabu search and its validity is illustrated through a comparative study.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.4 no.1
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• pp.129-142
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• 1980

The present paper discusses some problem areas in supplying information. As the world advances in civilization, we need exact and rapid information exchange, it may be said in this connection that we also feel keenly the necessity of the industrialization of the information. In accordance with the industrialization of the information, we can find the following phenomena: 1. Increase of present potentiality users. 2. Demand of high level information in accordance with the improvement of education level, 3. Increase of demand in the information materials in accordance with growth of research and development. 4. Contraction of the existing knowhow and degeneration of special field technique, 5. Increase of information concerned person for policy making in the government and in the industry. In the meantime, the information problem occurs for efficient management of information materials, in addition to numerical increase of various kinds, increase of users crate control and standardization problem, so it is needed to improve a mode of expression, structure, file and methods of usage. The librarian, as a information processor, should recognize that the information is national resources and improve the marketability of information industry. We need an administrative system of national level for the development of library in accordance with increase of an administrator who is engaged in information activities.