• 유체기계공업학회:학술대회논문집
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• 2001.11a
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• pp.165-170
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• 2001

An extensive range of pumping facilities are employed in the regional water supply system in metropolitan areas, and optimization and the systematic combination of the Pump facilities have direct bearing on the stability and economy of the water supply system concerned. These systems must be able to guarantee stability, efficiency and offer high reliability. Preparation of metropolitan area regional water supply system construction project must include a basic plan which takes into account the suitability of pumping facilities to be used, the environment in which facilities will be installed, man-power requirements and basic operational and management policies. This paper contains over-all analysis of the management of metropolitan area regional water supply systems as like Jayang, Paldang 1st pump station. In the study, it aims to prepare counterplan which will be operated and managed the pump upon the operational conditions and to suggest the proposal for water facilities codes to decides total head of pump in Korea.

• Management Science and Financial Engineering
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• v.11 no.1
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• pp.1-24
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• 2005

The results of a study of the coordination effect in stocking and promotional markdown policies for a supply chain consisting of a retailer and a discount outlet (DCO) are reported here. We assume that the product is sold in two consecutive periods: the Normal Sales Period (NSP) and the subsequent Promotional Markdown Sales Period (PSP). We first study an integrated supply chain in which managers in the two periods design a common system so as to jointly decide the stocking quantities, markdown time schedule, and markdown price to maximize mutual profit. Next, we consider a decentralized supply chain. An uncoordinated contract is designed in which decisions are decentralized to optimize the individual party's objective function. Here, three sources of system inefficiencies cause the decentralized system to earn a lower expected system profit than that in the integrated supply chain. The three sources are as follows: in the decentralized system the retailer tends to (1) stock less, and (2) keep a longer sales period, and the DCO tends to (3) stock fewer leftovers inventories and charge a higher markdown price. Finally, a numerical experiment is provided to compare the coordinated model with the uncoordinated model to explore factors that make coordination an effective approach.

• Proceedings of the KSR Conference
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• 2000.11a
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• pp.696-703
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• 2000

This paper describes the capacity calculation of power supply system for light Rail Transit Three factors are considered for the design i.e. substation arrangements, line configuration and substation power capacity. In this study, we considered all of them for capacity calculation of power supply system for LRT. At first DC-fed-traction system is introduced on an outline, a characteristics of train and fed network, and design method of substation arrangements. Optimal design procedures are described, and program for capacity calculation of the system is presented. In addition, the computer simulated results are computed with the conventional simple calculation method.

• Journal of the Korea Safety Management & Science
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• v.14 no.1
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• pp.129-136
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• 2012

This study proposes a collaboration system framework on the web service in a supply chain to implement an efficient virtual supply chain and improve an ability to fulfill received orders over a supply chain. The system based on the framework proposed in this paper plays an important role for automatic order negotiation and placing/receiving an order noticed in web service by the main system. Furthermore, it can evaluate the fulfillment of received orders over a supply chain by using the transaction results from hierarchically related vendors and establish efficient manufacturing plans. In a word, this system is the automated system for creating manufacturing plans, placing and receiving orders. A little more important main function of this system is that it has a dynamic evaluation capability about fulfillment with received orders over a supply chain, and improves the evaluation method of fulfillment ability with received orders with related to direct dealing vendors, which is a main problem in existing system. As a result, this system is able to reduce the work load of the sales and purchasing materials, production control division, to manage accurate inventory promptly, to maintain the optimal inventory level by analyzing the information of fulfillment ability with received orders, and to enhance the level of service for customers.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.280-283
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• 2008

This study is concerned with development of air supply system in 250kW MCFC fuel cell system. The turbo blower is decided as an air supply system to increase the efficiency of fuel cell system. The turbo blower consists of an impeller, two vaneless diffuser, a vaned diffuser and a volute. The cascade diffuser is used to raise the efficiency of turbo blower. An aerodynamic design was done by applying the repeating design procedure including a meanline design, a 3D geometry generation and fluid dynamic calculation. It is confirmed from meanline and 3D flow analysis results that the operating range is enough and design requirements are successfully achieved. The performance test results were also included in this paper.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2004.05a
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• pp.123-128
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• 2004

Semiconductor Wet Station has a very important place in semiconductor process. It is important that to discharge chemical with fit concentration and temperature using chemical supply system for clean process. The chemical supply system which is used currently is not only difficult to make a fit mixing rate of chemical which is need in clean process, but also difficult to make fit concentration and temperature. Moreover, it has high stability but it is inefficient spatially because its volume is great. We propose In-line System to improve system with implement analysis of fluid and thermal transfer on chemical supply system and understand problem of system.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2007.11a
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• pp.67-89
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• 2007

This study addresses manufacturers' ability to influence their supply chain network in order to adapt to their competitive environment. From the perspective of a manufacture, the supply chain comprises a network of suppliers and customers, and is theoretically viewed as a complex adaptive system. This study considers the following questions: (1) How can adaptability of supply chain network be operationally defined? (2) How does adaptability of supply chain network lead to combinative capabilities? (3) What is the influence of adaptability of supply chain network on business performance? Drawing on literature streams in supply chain management, operations strategy, organizational change and learning, and complexity theory, this study develops and tests the constructs and operational measures of adaptability of supply chain network and model the nomological set of relationships among constructs that form the basis of our theory. This study then develops and tests a model describing the outcomes of adaptability of supply chain network and its influence on combinative capability and business performance. Empirical results of this study show that adaptability supply chain network directly and positively affects combinative capability. Further, this study finds that adaptability of supply chain network does not impact business performance directly, but rather is mediated through combinative capability, which provides the requisite variety for firms to survive and thrive in dynamic environments.

• Journal of the Korean Solar Energy Society
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• v.25 no.2
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• pp.63-69
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• 2005

This study is the survey of a transition procedure of building services systems(heat source, HVAC, water supply) through the survey of existing office buildings, building design documents. The preference & major consideration of system selection is the engineer's opinions. The results of this survey can be used in selection of building services system design. In this survey, "Hot & cold water generator system" and "single duct CAV+FCU system", "Elevated water tank system" are selected. The most important consideration in system selection is the energy saving in heat source system, and comfort in HVAC system, and water pressure in water supply system. They prefer "steam boiler+absorption chiller system" for heat source system, "steam boiler+ice thermal storage system", "hot & cold water generator system", "district heating+absorption chiller system" : "single duct CAV+FCU system" and "single duct VAV+convector system" for HVAC system: and "booster pump system" for water supply system.

• Journal of the Korean Society for Railway
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• v.13 no.3
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• pp.278-282
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• 2010

Since a power supply substation of the magnetic levitation train system includes a inverter which is necessary to change the frequency of power, it has a different characteristic comparing to any other railway system. Nowaday a study for determining rating of facilities constituting a power supply system and modeling that system is undergoing. In this paper, a analysis model for the power supply system of the magnetic levitation train using the 3-level inverter is proposed. And the analysis for output characteristic is performed using the PSCAD/EMTDC program. The control method about the output of 3-level inverter for supplying power to loads in magnetic levitation train system is also described.

• Management & Information Systems Review
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• v.27
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• pp.149-172
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• 2008

Since the 9/11 terror attack, the event which caused supply chain disruption, supply chain security has becomes more important than ever before. Furthermore, such company's logistics strategies conflicting supply chain security as increased global sourcing, JIT manufacturing are increasing supply chain vulnerability. It could burden for global companies to strengthen supply chain security because not only it requires additional investment cost but also changes of companiy's global logistics strategy. However, on the other hand, supply chain visibility and resilience can be improved through supply chain security. In addition, it allows companies to stabilize supply chain structure as well as rapid and flexible response to market demand. The key issue is balancing between efficiency and supply chain security. To do this, identifying risk elements under the supply chain and assessing vulnerability of each supply chain components should be performed before developing efficient supply chain security management system without obstructing supply chain efficiency.