• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1612-1615
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• 2009

Water supply reliability indexes (WSRI) is estimated for assessment of water supply capacity in the downstream for parallel reservoir system in Nakdong River, South Korea, using allocation rule (AR) according to the water supply capacity of each reservoir and the characteristic of parallel reservoir system. The result of the analyzing parallel reservoir system for Andong and Imha reservoir in Nakdong River does not include evidences available enough to decide whether the results of water supply analysis are excellent in the current reliability evaluation or not. However, AR (C) shows a good result in the water supply capacity for each reservoir based on the connected operation system and the total water supply capacity at the control point of downstream by the average water supply capacity and possible range of water supply capacity suggested by this study. The average water supply capacity is analyzed by the reliability of monthly average water supply capacity. Furthermore, the possible range of water supply capacity is estimated by the standard deviation when water deficit occurs. Therefore, AR (C) is useful to establish and estimate the planning water supply capacity according to the monthly water supply condition and the possible range of water supply capacity when the water supply capacity deficit occurs, South Korea.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.3
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• pp.193-200
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• 2009

The ventilation system of apartments can be divided by supply and exhaust fan, supply fan and exhaust free and supply free and exhaust fan. Recently, the individual ventilation system and central ventilation system which is combined cooling system with duct system are applied to apartment ventilation system. The airflow pattern is affected by location of supply unit and exhaust unit in indoor. This study is to investigate the proper distance between supply unit and exhaust unit using CFD. As a result of this study, the proper distance between supply unit and exhaust unit could be suggested at the interval of 3 m in supply and exhaust fan system and 2.5 m in supply fan and exhaust free.

• Journal of Korean Society of Water and Wastewater
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• v.31 no.2
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• pp.177-186
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• 2017

This study concerned the analysis on the efficiency of the conversion of water tank type supply system to direct water supply system to examine the feasibility of the conversion, as well as the calculation of optimal conversion range that enables the supply of safe, high-quality water at stable pressure in accordance with the standards of water supply facility. The results of this research showed that when converting water supply system from water tank type supply system to direct water supply system, more nodal points could be properly converted and more reduction of electricity usage was expected in case water pressure rather than residence time was fixed. This means that higher efficacy can be obtained by fixing water pressure when converting water supply system. However, since the number of the locations that received on-spot inspection was small and the electricity usage measured was not exclusively by water supply facility, it is difficult to judge that such reduction of electricity usage accurately represents reduced electricity usage by water supply facility alone. therefore, after having secured on-spot information about a larger number of locations in apartment complexes that have converted water supply system, and utilizing information about electricity usage exclusively by water supply facility, the proposed method of this research could be applied to accurately deducing expected reduction of electricity usage by water supply facilities of various other apartment complexes. It is also considered possible to deduce an effective operation method of water supply system by finding out an area that shows low pressure or low residual chlorine concentration in the optimal conversion range of water supply, followed by estimating the proper location of pumping station or the proper chlorine dosage at the power purification plant that supply water to the target area.

• Journal of Environmental Health Sciences
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• v.5 no.1
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• pp.76-85
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• 1978

This survey was undertaken for the period seven month beginning January 15, 1977 and ending July 31, 1977 to detect the general sanitary status of the villages and the villagers and, at the same time, analyse quality of water sources with emphasis on a total of 1,256 households dividing into three different groups: such as, 280 households were selected as random samples from the area of the sophisticated piped water supply system, 122 households from the area of the simplified water supply system and finally 854 households from the area of nonpi-ped water supply system. The following results were concluded after quality of water sources had been analysed and conditions of the environmental sanitation had been reviewed: 1. 11.2% of the respondents from the area of the sophisticated piped water supply system responded that quantity of drinking water lacked to meet their demand while 30.6% of the villagers from the area of nonpi-ped water supply system responded quantity of drinking water didn't meet their demand. 2. 30.8% of the.respondents from the area of the sophisticated water supply system responded that contaminating source located within 15 meters from the water source while 54.4% of the respondents from the non-piped water supply system claimed the same. 3. It was found that water from all sampling areas were positive in coliform group with exception of Moonsan which is one of the sophisticated piped water supply system groups and the number of general bacteria exceeded the government standard criteria of water quality in the area of the nonpi-ped water supply system. 4. In relation with time requirement to draw water in the area of non-piped water supply system, 76 respondents claimed it requires less than 15 minutes to draw water, 15.0% claimed 15 to 30 minutes and 9.0% claimed more than 30 minutes. 5. In relation with knowledge on sanitation of drinking water, 30.8% of respondents from the area of the sophisticated piped water supply system and 41.8% of respondents from the area of nonpiped water supply system denied possible existence of germ in drinking water they drink, while 17.4% of the respondents from the area of the sophisticated water supply system and 50.2% of non-peped water supply system thought it safe to drink water without any treatment. 6. 60.0% of the respondents from the area of non-piped water supply system and many of them believed that their health status will be improved by installation of a sophisticated water supply system in their area. 7. The respondents from the areas of piped water supply sytem expressed greater concern over drinking water sanitation than those from the areas of non-piped water supply system and sanitary conditions were found the same. It was, therefore, proved that knowledge of environmnntal sanitation contributed a great deal to improve sanitary conditions of the villages and villagers and at the same time health education, especially environmental sanitation, will be played a important role to improve their sanitary conditions.

• Journal of Korean Society of Water and Wastewater
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• v.27 no.1
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• pp.1-10
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• 2013

Major issues in water supply service have changed from expansion of service area to improvement of service quality, i.e., water quality and safety, and early response to emergency situation. This change in the service concept triggers the perceptions of limitation with the current centralized water supply system and of necessities of decentralized (distributed) water supply system (DWSS), which can make up the limitations. DWSS can reduce the possibility of water supply outage by establishing multiple barriers such as emergency water supply system, and secure better water quality by locating treatment facilities neighboring consumers. On the other hand, fluctuation of water demand will be increased due to the reduced supply area, which makes difficult to promptly respond the fluctuating demand. In order to supplement this, hybrid water supply system was proposed, which combined DWSS with conventional water supply system using distributing reservoir to secure the stability of water supply. The Optimal connection point of DWSS to existing water supply network in urban area was determined by simulating a supply network using EPANET. Optimal location of decentralized water treatment plant (or connection point) is a nodal point where changes in pressure at other nodal points can be minimized. At the same time, the optimal point should be selected to minimize hydraulic retention time in supply network (water age) to secure proper water quality. In order to locate the point where these two criteria are satisfied optimally, Distance measure method, one of multi-criteria decision making was employed to integrate the two results having different dimensions. This methodology can be used as an efficient decision-support criterion for the location of treatment plant in decentralized water supply system.

• International Journal of Air-Conditioning and Refrigeration
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• v.11 no.2
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• pp.67-72
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• 2003

A partition integrated air supply system can provide highly personalized environmental control. The supply air is brought up through raised floors and supplied to outlets located on the partition panels. The purpose of this paper is to find out the best design of outlets for optimal occupant comfort within a personal task area. Real scale experiments were conducted to allow for comparisons of outlet designs within a personal task area. Experimental results indicate that the location of an outlet is the most critical factor in improving the efficiency of supply air distribution of a personal task area. Thermal characteristic comparisons were made between the under-floor and the partition supply systems. Experimental results suggest that the partition supply system is more efficient than the under-floor supply system in terms of cooling. Such a system allows occupants to personally control their immediate environment, resulting in higher productivity.

• Journal of the Korea Safety Management & Science
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• v.6 no.3
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• pp.187-196
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• 2004

By successful establishment of Supply Chain Management System they should make the supply chains speedy and combine production information system with the outcome system and thus they reinforce the competition of the production system of local enterprises in accordance with the rapid decision making. Supply chain coordination improves if all supplier of chain take actions that together increase total supply chain profits. To design of Modularity by the grouping supplier, the proposed method is to develop the most appropriate production system models through the reflection of JIT system in the Supply Chain Management which is necessity of the times and its importance. The objects of this study is to develop the most appropriate production system Model and optimal profit model in the process line and to provide the enterprises with the models which are based on the Supply Chain Management.

• Journal of Distribution Science
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• v.22 no.1
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• pp.95-103
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• 2024

Purpose: Focusing on the complex supply chain operations beyond the simple dyadic relationship, this study evaluates the performance of the revenue sharing contract in three stage supply chain system. Research design, data, and methodology: The optimization model is developed to describe the supply chain system where one manufacturer, one wholesaler, and one retailer exist and pursue the maximum level of their own profits. In the numerical examples of the proposed supply chain model, two types of the revenue sharing contract, pairwise and spanning methods, are tested and their performances are compared with the traditional system. Results: The numerical analysis reveals that both types of the revenue sharing contract outperform the traditional system. All supply chain members can achieve the improved profits only when they determine the proper combination of revenue share ratios and price discount rates. Conclusions: This study finds out that both pairwise and spanning revenue sharing contracts can make the positive outcome that is acceptable to all members in three stage supply chain system. When the proper contract content is agreed among the supply chain members, the revenue sharing contract has the potential to be the practically feasible collaboration program for the multiple stage supply chain system.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1309-1312
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• 2005

A multi-chemical supply system is developed and applied to a wet station, which uses the multi-chemical process in one bath. To control the concentration of two chemicals, control logic of a supply pump is programmed using the programable logic controller (PLC). By using the multi-chemical supply system, wet station with single bath is applied to cleaning process using multi chemicals such as buffed oxide etchant (BOE) and standard clean 1 (SC-1). The concentration of each chemical is measured in the bath to verify the multi-chemical supply system. The control range in the each chemical concentration is measured to 1.33weight% in NH4OH and 0.23weight% in H2O2. The multi-chemical supply system can be movable and usable as an independent module of fixed wet station. By simply midifying the PLC, a multi-chemical supply system can be developed for a wet station.

• Journal of Distribution Science
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• v.20 no.6
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• pp.125-135
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• 2022

Purpose: The revenue sharing contract has been used in various industries and it is expected to coordinate the individual companies' operations in a way to improve the whole supply chain performance. This study evaluates the performance of the revenue sharing contract to find out whether this contract achieves its original goal, the supply chain coordination. Research design, data, and methodology: The profit optimization models are developed to represent two stage supply chain system with a supplier and a buyer. By using the numerical examples of the proposed mathematical models, this study examines whether this supply chain contract coordinates the supply chain system. Results: The numerical examples show that the revenue sharing contract does not make the same supply chain profit as the centralized system does. With the proper combination of the wholesale price discount rate and revenue share ratio, both manufacturer and retailer can obtain increased profits from the revenue sharing contract. Conclusions: The outcomes of the numerical analysis imply that the revenue sharing certainly improves the supply chain performance but it does not fully coordinate the supply chain system. By controlling the wholesale price and revenue share ratio, every supply chain member can be beneficiaries of this supply chain contract.