• Journal of Power Electronics
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• 제10권1호
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• pp.91-96
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• 2010

In this paper, a simplified control algorithm for a three-phase, four-wire unified power quality conditioner (UPQC) is presented to compensate for supply voltage distortions/unbalance, supply current harmonics, the supply neutral current, the reactive power and the load unbalance as well as to maintain zero voltage regulation (ZVR) at the point of common coupling (PCC). The UPQC is realized by the integration of series and shunt active filters (AFs) sharing a common dc bus capacitor. The shunt AF is realized using a three-phase, four leg voltage source inverter (VSI) and the series AF is realized using a three-phase, three leg VSI. A dynamic model of the UPQC is developed in the MATLAB/SIMULINK environment and the simulation results demonstrating the power quality improvement in the system are presented for different supply and load conditions.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 동계학술발표대회 논문집
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• pp.21-26
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• 2005

We performed the numerical analysis on the characteristics of indoor air quality and local supply index with a variation of supply · exhaust airflow rate. We analyzed the local supply index and carbon dioxide concentration at the room and breathing zone with respect to the variation of the supply · exhaust airflow rate. From the numerical results, we found that local supply index was affected but carbon dioxide concentration was hardly affected by the variation of the airflow rate in the room. And we also knew that carbon dioxide concentration was raised in despite of the increment of the supply airflow rate in the breathing zone. After this study it is necessary to analyze the local exhaust index when we evaluate the state of the ventilation in the room.

• 한국의료질향상학회지
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• 제6권1_2호
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• pp.150-160
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• 1999

Background : Because hospitals had to faced with financial hardship, we have to have more effective hospital management. In this study, we tried to improve job performance and to reduce cost maintaining safety in fields of patients care. Methods : Central Supply Room(CSR) staffs taught strategy of material cost reduction to middle level managers and staffs 14 times. All staffs and voluntary service workers, working in 33 nursing units, participated in this activity. We developed questionnaire to check the degree of participate in cost reduction activity and job performance in CSR, and quality improvement in the wards. Two hundred questionnaires were distributed and 197 returned. Results : Because CSR staffs developed new items and every item was managed at each department, stocks of each department were reduced. Overall, by comparing before and after cost reduction activity, almost 1.2 billion won reduced for one year. Staffs' loyalty and spirits of cost reduction were improved by changing clothes and duty environment. Furthermore, these activity improved patients' satisfaction. Conclusion : We suggest that CSR activity in a university hospital contributes to improve job performance and to reduce cost without any problem in patient care.

• 한국환경보건학회지
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• 제5권1호
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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.

• 품질경영학회지
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• 제46권4호
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• pp.959-972
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• 2018

Purpose: This study developed a simulation model that incorporates the uncertainty of demand and yield to obtain optimized results for supply chain coordination within environmental constraints. The objective of this study is to examine whether yield management for perishable products can achieve the goal of supply chain coordination between a single buyer and a single supplier under a variety of environmental conditions. Methods: We investigated the efficiency of a revenue-sharing contract and a wholesale price contract by considering demand and yield uncertainty, profit maximizing ratio, and success ratio. The implications for environmental variation were derived through a comparative analysis between the wholesale price contract and the revenue-sharing contract. We performed Monte Carlo simulations to give us the results of an optimized supply chain within the environments defined by the experimental factors and parameters. Results: We found that a revised revenue-sharing contracting model was more efficient than the wholesale price contract model and allowed all members of the supply chain to achieve higher profits. First, as the demand variation (${\sigma}$) increased, the profit of the total supply chain increased. Second, as the revenue-sharing ratio (${\Phi}$) increased, the profits of the manufacturer gradually decreased, while the profits of the retailer gradually increased, and this change was linear. Third, as the quality of yield increased, the profits of suppliers appear to increased. At last, success rate was expressed as the profit increased in the revenue-sharing contract compared to the profit increase in the wholesale price contract. Conclusion: The managerial implications of the simulation findings are: (1) a strategic approach to demand and yield uncertainty helps in efficient resource utilization and improved supply chain performance, (2) a revenue-sharing contract amplifies the effect of yield uncertainty, and (3) revised revenue-sharing contracts fetch more profits for both buyers and suppliers in the supply chain.

• 산경연구논집
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• 제10권6호
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• pp.19-27
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• 2019

Purpose - The purpose of this study was to examine quality improvement priorities by examining not only quality classifications but also PCSI (Kano, 1984) of mobile app service qualities of general hospitals in the Metropolitan Area and offer potential improvements. Research design, data, and methodology - The study examined five of service qualities, including app design, reaction, convenience, safety and supply of information by precedent studies. 20 test items were selected. A total of 60 positive and negative questions to estimate customer satisfaction and PCSI was investigated. The author collected 300 copies from interviewees who made use of the app services of 13 general hospitals within one year, and classified quality factors by using table of quality assessment and also estimated the customer satisfaction index (Timko, 1993). The study made quality improvement priority by the PCSI index. Results - Reaction of the mobile app service quality ranked the highest PCSI, and payment safety ranked the highest, and customer support and supply of the information ranked high as well. It was observed that design ranked comparatively lower in these categories. Conclusion - Safety, reaction and supply of information should be prioritized to reorganize and improve the mobile app services.

• 경영과정보연구
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• 제30권2호
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• pp.113-131
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• 2011

본 연구는 경쟁심화와 고객서비스 욕구의 다양화로 인해 물류서비스 품질 및 공급사슬 관리에 관한 연구가 중요하게 부각되고 있는 시점에서 물류서비스 품질요소에 대한 공급사슬 파트너십의 구성원들의 지각 차이를 비교분석하였다. 이를위해 공급사슬 내에서 공급자와 수송업자, 구매자가 중요하게 판단하는 물류서비스 품질에 대한 인식을 측정하여 t-test를 실시하였다. 분석결과 공급사슬 내의공급자, 수송업자, 구매자가 중요하게 평가하는 물류서비스 품질 요소의 차이가 큰 것으로 나타났다. 또한 공급사슬 파트너십에서 시장지향성과 장기지향성이 높은 공급자와 낮은 공급자간에 중요도 차이 지각을 비교한 결과, 시장지향성과 장기지향성이 낮은 경우에는 대부분의 항목에서 집단 간의 차이를 보이고 있는 반면, 높은 경우에는 상호작용성에 대부분의 집단 간에 중요도 평가 차이가 없는 것으로 나타났다.

• 품질경영학회지
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• 제47권1호
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• pp.163-186
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• 2019

Purpose: The purpose of this study was to present a methodology for assessing the efficiency of supply chain quality management considering characteristics of defense industries to provide academic and policy implications for strengthening quality competitiveness of military supplies. Methods: Using the defense industry's empirical data, conduct an efficiency evaluation by utilizing a multi-stage DEA/Entropy Model for defense industries subject to the quality level survey of military goods manufacturers in 2017. Results: The results of this study are as follows; the first step of the multi-stage DEA model, Quality Management Performance Efficiency Analysis, shows that the CCR model and the BCC model are more efficient than the parent company. the second stage of the multi-stage DEA model showed that the CCR model was slightly more efficient than the parent company and the BCC model was more efficient than the parent.the overall efficiency value of the multistage DEA model, calculated by multipointing the efficiency value of the first stage by the second stage, was more efficient than the parent. Conclusion: The results of this study show that the efficiency of supply chian quality management performance and profitability in the defense industry can be analyzed for the first time using the multistage DEA/Entropy model to identify specific inefficiencies and support objective decision making.

• 한국프랜차이즈경영연구
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• 제13권3호
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• pp.17-30
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• 2022

Purpose: Recent emergence of diverse businesses in the distribution industry has led small and medium-sized retailers and their distribution logistics centers to face difficulties. Transactions between companies are connected within a supply chain, and the companies have relationships in the form of a supplier and a buyer. Therefore, it is important to identify causes of problems among companies through supply chain and strategic partnerships, thus developing optimal management plans and maximizing performances of companies. This study proposes that sustainable supply chain management consists of product quality, price quality, distribution quality, and promotion quality based on stakeholder theory and resource-based view. This study examined the impacts of sustainable chain management factors on satisfaction and win-win cooperation. Research design, data, and methodology: In the proposed model, satisfaction plays a mediating role in the relationship between sustainable chain management and win-win cooperation. The data were collected from 245 owners who use small and medium-sized distribution logistics center and analyzed using 2SLS (two-stage least square) with SPSS 28.0. Exploratory factor analysis and correlation analysis were used to assess the validity and reliability of constructs. Results: The findings are as follows. In the case of the total and Nadeulgage samples, product, price, and distribution quality had a significant positive effect on satisfaction, but in the case of Neighborhood super, product and price quality have a significant positive effect on satisfaction. Satisfaction has a significant positive effect on win-win cooperation in the overall, Nadeulgage, and Neighborhood super. Satisfaction plays a partial or full mediating role in the case of total, Nadeulgage, Neighborhood super. Conclusions: This study emphasized the need for sustainable supply chain management of small and medium-sized distribution logistics centers by examining the relationship between small and medium-sized distribution logistics centers and chain stores. It was found that store satisfaction plays an important role in the win-win cooperation between small and medium-sized distribution logistics centers and chain stores. Small and medium-sized distribution logistics centers can maximize product quality, price quality, distribution quality, and promotion quality by understanding the effect of chain store-related satisfaction and win-win cooperation on chain stores.

• 유통과학연구
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• 제12권6호
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• pp.31-39
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• 2014

Purpose - Environmental issues, climatic changes, and greenhouse gases are problems to be solved at a global level. With an increased emphasis on the environmental and social responsibility of the management of companies, the manner in which companies approach quality-oriented culture and their individual sustainability management are being discussed as truly important issues to help them secure their competitiveness and growth strategies. This study proposes strategic directions to help manufacturers not only in expanding their competitive quality-oriented company culture but also in strengthening their sustainability management abilities. This study conducts a literature review and empirical research to examine how significantly the variables of a quality-oriented company culture, customer-centered management, and process-centered and supply chain management-centered cooperation affect sustainability management performance in relation to economic profitability, environmental integrity, and social responsibility. Research design, data, and methodology - To verify research models and hypotheses, the study examined 170 companies using a questionnaire survey conducted over six weeks, and involved the performance of data analysis on 146 samples. Questionnaire responses were calibrated based on a Likert scale. The study used the Smart PLS 2.0 program designed for PLS (partial least squares), an analysis instrument of SEM (structural equation modeling). The study then verified empirical research hypotheses working on reliability analysis, validity analysis, factorial analysis, and path analysis. Results - Among the nine hypotheses, four are accepted and the rest are rejected. A quality-oriented company culture focusing on customer-centered management significantly influenced the maintainability management performance of environmental integrity and social responsibility, while economic profitability was dismissed. A process-focused quality-oriented company culture was significantly concerned with economic profitability but not with environmental integrity or social responsibility. A supply-chain cooperative company culture had a significant effect on economic profitability but not on environmental integrity or social responsibility. Conclusion - This study proposes strategic directions to help manufacturers expand their competitive quality-oriented company culture as well as strengthen abilities with sustainability management. It conducts a literature review and empirical research to examine how significantly the variables of quality-oriented company culture, customer-centered management, and process-centered and supply chain management-centered cooperation affect sustainability management performance in relation to economic profitability, environmental integrity, and social responsibility. There are two main conclusions. First, companies should consider the need for social responsibility management and environmental transparent management-focused maintainability management as avenues to create new markets and business, thereby helping the companies secure a reputation for having a customer and process-centered quality-oriented company culture by creating shared values between supply chains and enabling win-win situations through cooperation. Second, we are marching towards a creative win-win era from a society of conflicts and ruptures. Companies should understand that social responsibility management and supply chain management (SCM)-focused cooperation are the foundations of sustainable development, as they try to improve their culture while pursuing both win-win relationships with interested parties and equity in various conflictive relations.