• 산업공학
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• 제22권1호
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• pp.73-84
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• 2009

In this paper, we propose a dispatching algorithm for constructing a Factory Operating System (FOS) which can operate semiconductor fabrication factories more efficiently and effectively. We first define ten dispatching criteria and propose two methods to apply the defined dispatching criteria sequentially and simultaneously (i.e. fixed dispatching architecture). However the fixed type methods cannot apply the criteria adaptively by considering changes in the semiconductor fabrication factories. To overcome this type of weakness, an adaptive dispatching architecture is proposed for applying the dispatching criteria dynamically based on the factory status. The status can be determined by combining evaluation results from the following three status criteria; target movement, workload balance, and utilization rate. Results from the shop floor in past few periods showed that the proposed methodology gives a good performance with respect to the productivity, workload balance, and machine utilization. We can expect that the proposed adaptive dispatching architecture will be used as a useful tool for operating semiconductor fabrication factories more efficiently and effectively.

• 항공우주산업기술동향
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• 제8권2호
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• pp.46-53
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• 2010

이 논문에서는 위성항법시스템의 운영 현황과 개발 계획에 대하여 기술하였다. 미국의 GPS(Global Positioning System)와 러시아의 GLONASS(Global Navigation Satellite System), 유럽의 Galileo, 중국의 Beidou/Compsss, 그리고 일본의 QZSS(Quasi-Zenith Satellite System) 에 대하여 시스템의 구성과 운영 위성 상태에 대하여 기술하였으며, 각 시스템의 개발 계획과 현대화에 대하여 기술하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 추계학술대회 논문집 전력기술부문
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• pp.181-183
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• 2008

This paper suggests local voltage control method to achieve coordinative control between STATCOM and other reactive power resources, such as Shunt Capacitor/Reactors and OLTC. Voltage/Reactive power control has various difficult aspects to control because of analysis and system dynamics error. This control method suggests practical algorithm regarding system voltage and reactive power status which is easy to implement in substation basis. In normal status, STATCOM-Shunts-OOTC are in operation. In emergency status, OLTC is locked. This algorithm is tested and verified in EMTDC.

• 수산해양교육연구
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• 제29권1호
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• pp.169-179
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• 2017

The purpose of this research is to identify the overall operation status of the marine program, which operates in the Department attempted, in various qualities and operational programs consisting of lecturers derives the problem, and to the policy proposal accordingly. In order to complete the purpose, to analyzed based on the status of marine programs of the Marine Training Center Chungcheong Cluster of three Education Offices from 2014 until the first half of 2016. In addition to direct visit the scene to confirm the status of the data collected through field surveys and interviews were officials confirm the validity of the data, and also to obtain additional study. In conclusion, First, Establish measures for the reduction of blind spots urgent law. Second, Appliances installed for program development and Instructors training.

• 융합경영연구
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• 제7권1호
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• pp.1-14
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• 2019

Purpose - Currently, the economic globalization has become a common channel for China's enterprise to perform the international economic activities. Due to this background, this paper tries to analyze the influence of internationalization level on operation performance of enterprises. Research design, data, and Methodology - This paper aims at 296 companies going listed in Shanghai Stock Exchange and Shenzhen Stock Exchange. The data about the listed companies during the 12 years from 2005 to 2016 have been collected. Relevant theories, including the theory of comparative advantage, monopolistic advantage and product life cycle in developed countries as well as the small scale technology and state on localized technological capacities in developing countries, have been summarized to provide theoretical basis for the influence of international operation on operation performance of the enterprises. Moreover, the current status of international operation of China's enterprises, including the dynamic cause of the internationalization of China's enterprises, its competitive advantage and disadvantage as well as the interest and potential risk of the internationalization, have been also analyzed. Results - Via adopting the panel data to conduct an empirical analysis, It can be found that the relationship between international operation level and operation performance of China's enterprises can be expressed as the S-curve of declining, rising and declining again. Conclusions - This paper has taken the lead in using Ohlson corporate value model to fill the gap in the relevant researches in China. It can also provide guidance for the international operation of China's enterprises. Meanwhile, the two systems for international operation and performance evaluation index have been put forward. The performance of international operation can be classified as financial performance or corporate value so that the operation effect of those China's enterprises going abroad can be better evaluated.

• 한국안전학회지
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• 제38권1호
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• pp.25-33
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• 2023

In this study, we determined the failure rate and fire status of electric motors widely used in domestic and industrial devices and analyzed the associated fire risks by identifying the electrical and temperature characteristics of electric motors under the normal and restrained operation modes in industrial sites and laboratories. A 2.2kW motor used for driving a conveyor during the vulcanization process in a rubber product manufacturing plant was employed as the study object and was exposed to a high- temperature environment as this motor is widely used in industrial sites. The current amplitude was 4.45-4.50 A during normal operation and 38.2-41.5 A during restrained operation due to the pinching of products and semi-finished products (i.e., 8.5 times higher than that during normal operation). The leakage current amplitude was 0.33 mA during both operation modes. The temperature of the workplace in summer was 42.38℃, indicating a poor environment for the installed motor. In the laboratory, the current and temperature of the coil inside a 3.7kW motor were measured under the restrained operation mode as performing measurements of the coil inside the motor in industrial sites is challenging. The current amplitude during normal operation was 3.5 A, whereas that during restrained operation for 30 s was 51.7-58.6 A, which is 14.8-16.7 times higher than that of normal operation. Moreover, the temperature of the motor coil increased from 22.9℃ to 101℃. Based on the experimental data, we derived the temperature increase formula according to the restrained operation time by performing a regression analysis and verified the time at which the temperature exceeded the stipulated limit for the insulation grade. The findings presented in this paper can be utilized to establish fire-prevention measures and perform safety management of motors of the same type or with a similar capacity.

• 한국농공학회논문집
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• 제65권5호
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• pp.37-49
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• 2023

The drought risk has been increasing recently due to climate change causing the extreme climate to be more frequent. In order to supply agricultural water stably under drought, it is necessary to operate an agricultural reservoir in response to drought. To this end, it is crucial to establish appropriate drought response operation rules considering weather conditions and reservoir status. In the reservoir operation simulation, the supply amount differs from the actual reservoir supply for many reasons, including maintaining water levels for supply and accommodating farmers' requests. So, for a more realistic reservoir operation simulation, it is necessary to reflect the reservoir operation rules of the actual water management site. Therefore, in this study, through a survey, the standards for limitation of agricultural water supply applied to agricultural reservoirs in Korea were investigated, and the criteria for drought response reservoir operation (DRO) were established based on the survey. Then, the DRO was applied to the irrigation period for nine subject reservoirs. The applicability was evaluated by comparing the DRO result to the operation result of HOMWRS (Hydrological Operation Model for Water Resources System). The reservoir drought index, storage rate, and daily supply were compared for evaluation. From the result, DRO showed more stable operation results in most cases against drought as it has fewer days of water supply limitation and a somewhat reservoir storage rate which can be utilized for prolonged drought.

• 한국구조물진단유지관리공학회지
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• 제17권1호
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• pp.20-29
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• 2013

• 한국식생활문화학회지
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• 제24권6호
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• pp.721-727
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• 2009

In this study, the current status of the business foodservice industry, evaluation of leftover food and customer satisfaction with foodservice at direct operation and consignment foodservice businesses in Chungbuk were examined. This study has managerial implications in terms of improving the quality and effectiveness of the business operation of the foodservice industry. The sample size of this study included 800 customers who use foodservices provided by 11 selected businesses including 6 direct operation and 5 consignment foodservice businesses. From these 800 customers, a total of 692 were used (direct operation foodservice (n=361) and consignment foodservice (n=331) businesses). The results were as follows; First, as for the main reasons for using the employee restaurants in types of direct operation and consignment foodservice business, 'the close location' had the high percentage. Approximately 41% of respondents were not satisfied with the foodservice in the employee restaurants. Second, leftover food from consignment foodservices was higher than that for direct operation foodservices. Third, there were significant differences in customer satisfaction with five areas of foodservice between the two types of food service businesses: food, sanitation, feeding environment, mealing process and information and service. Customer satisfaction in the direct operation foodservice was higher than that of the consignment foodservice. In terms of the satisfaction level of foodservices, mealing process was the highest, followed by sanitation, food, and information and service in the direct operation and consignment foodservice businesses. Overall, satisfaction with the business foodservice was affected by the customers' satisfaction in five areas of foodservices (e.g., food, sanitation, feeding environment, mealing process, information and service). Especially, 'food' and 'information and service' were important areas for determining overall customer satisfaction with foodservice. In addition, the overall satisfaction was negatively correlated with the quantity of leftover food in the direct operation and consignment foodservice business.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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• pp.64-66
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• 2006

DATS will connect with IMPS and LHGS to perform the reception of sensor data and the transmission of user's meteorological data, LRIT and HRIT. MODEM/BB will perform the de-commutation of received sensor data as MI and GOCI raw data according to VCID before sending them to MI and GOCI IMPS, respectively. Especially, MODEM/BB in SOC needs to be connected to six clients that consist of the primary and backup IMPS of MSC, KOSC and SOC. On the other hand, LRIT and HRIT delivered from LHGS are encoded as VITERBI and modulated by MODEM/BB. Considering sensor data transmitted from COMS, the assumed format and size of CADU are described in this paper. Finally, results related to the status of received LRIT and HRIT by frame synchronizer in user station are also described.