• Journal of the Semiconductor & Display Technology
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• v.13 no.2
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• pp.29-35
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• 2014

In this study general solar cell production process was complemented, with research on improvement of solar cell efficiency through surface structure and thermal annealing process. Firstly, to form the pyramid structure, the saw damage removal (SDR) processed surface was undergone texturing process with reactive ion etching (RIE). Then, for the formation of smooth pyramid structure to facilitate uniform doping and electrode formation, the surface was etched with HND(HF : HNO3 : D.I. water=5 : 100 : 100) solution. Notably, due to uniform doping the leakage current decreased greatly. Also, for the enhancement and maintenance of minority carrier lifetime, antireflection coating thermal annealing was done. To maintain this increased lifetime, front electrode was formed through Au plating process without high temperature firing process. Through these changes in two processes, the leakage current effect could be decreased and furthermore, the conversion efficiency could be increased. Therefore, compared to the general solar cell with a conversion efficiency of 15.89%, production of high efficiency solar cell with a conversion efficiency of 17.24% was made possible.

• Journal of the Korean Institute of Educational Facilities
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• v.12 no.6
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• pp.36-43
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• 2005

The purpose of this study is the examination of the possibility as grasping the circumstance which is the time required from programming to design process in schools which are established newly and investigating the consciousness of the user's participation, because we need a user participation process in the programming to design process to improve the level of design. The above-mentioned purpose is the reason that this study composes the second grade. This study shows the entirely necessary time to work each step as collecting the data of programming-design process to 33 schools which are established for 4 years between 2002 and 2005 by Busan metropolitan city office of education, and the reason why they need a time each step. As the result of this study, the school established by the purpose of land development business takes more time than the school of learning environment improvement and of reconstruction & transfer case. Because of the change of land for school, we have to take a cautious approach to select the land for school in the future when developing the land. The time required from programming to design process in reconstruction & transfer case is the shortest even though it is different a little according to the kind of schools.

• Journal of the Korea Safety Management & Science
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• v.23 no.3
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• pp.27-33
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• 2021

The purpose of this study is to present a novel indicator for analyzing machine failure based on its idle time and productivity. Existing machine repair plan was limited to machine experts from its manufacturing industries. This study evaluates the repair status of machines and extracts machines that need improvement. In this study, F-RPN was calculated using the etching process data provided by the 2018 PHM Data Challenge. Each S(S: Severity), O(O: Occurence), D(D: Detection) is divided into the idle time of the machine, the number of fault data, and the failure rate, respectively. The repair status of machine is quantified through the F-RPN calculated by multiplying S, O, and D. This study conducts a case study of machine in a semiconductor etching process. The process capability index has the disadvantage of not being able to divide the values outside the range. The performance of this index declines when the manufacturing process is under control, hereby introducing F-RPN to evaluate machine status that are difficult to distinguish by process capability index.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.5
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• pp.2135-2146
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• 2013

Most researches about residential improvement projects deal with different process phase in order to examine important affecting variables. The main purpose of this study is to identify influential change of locational variables according to the process of residential improvement projects. Generally the residential improvement project consists of four phases such as site designation, project committee approval, residents association establishment and final project approval. The discriminant and correlation analyses are employed to examine the changes of locational variables by each phase of the project process. In residential redevelopment projects, the finding shows that locational variables in the final project approval phase act differently from those in the other phases. On the other hand, the variables act similarly among the four phases in the case of residental rebuilding projects although the significant level of discriminant analysis result, in the site destination phase, is relatively low significance. Therefore, there is no difference among the project process phase to examine to what extent of the residential improvement projects.

• Journal of Food Hygiene and Safety
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• v.15 no.3
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• pp.186-198
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• 2000

The quality of the management of sanitation in food service establishments (school lunch programs, hospital patient food services, and commercial catering food services) in Korea was reviewed and evaluated, and ten strategies fur future improvement were suggested. They were: (1) An increase of qualified manpower and improvement of the professional training of the staff; (2) Obtaining special facilities exclusively for food service; (3) Improvement of facilities especially the kitchens; (4) Improvement of policy fur procuring raw materials and being assured of their quality by designing some standards and specifications for the raw materials to be purchased; (5) Production and use accurate and reliable kitchen apparatus and instruments; (6) An increase of the laboratory apparatus and instruments for inspection and evaluation of the sanitary level of raw materials and food service environments; (7) Enforced improvement of personal hygiene of the staff; (8) Use of a variety of methods in sanitary education and training; (9) Actively inspect the quality of imported foods; (10) Strengthening the research and accumulation of background data regarding sanitation management. There is a long process from the production of food to eating. The cooking process is the ultimate end of preparation of food before eating. This process sometimes increases the occurrence of food-borne diseases if we mishandle the food, even we obtained safe food. The process can also remove health hazards and reduce the risk from the hazards if we handle the food well although we have unsafe foods. This means the cooking process is a major key to preventing food-borne diseases. The concepts of hazard analysis critical control point (HACCP) should be applied and practiced in food service establishments in Korea as soon as possible.

• 한국데이터정보과학회:학술대회논문집
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• 2005.04a
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• pp.7-17
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• 2005

Consider a stuffing process where sausage-casings are filled with sausage-kneading. One of the most important factors in the stuffing process is weights of stuffed sausages. Sausages weighting above the specified limit are sold in a regular market price for a fixed price, and underfilled sausages are reworked at the expense of reprocessing cost. In this paper, the sausage stuffing process is inspected for improving productivity and quality levels. Several statistical process control tools are suggested by using real data obtained from a Korean Vienna sausage company.

• Journal of the Korean Data and Information Science Society
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• v.16 no.4
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• pp.823-833
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• 2005

This paper deals the TFT-LCD process and quality, process control problems of the process. For improvement of the process quality and yield, we apply a data mining technique to the LCD industry. And some unique quality features of the LCD process are also described. We describe some preceding researches first and relate to the TFT-LCD process and the problems of data mining in the process. Also we tried to observe the problems which need to solve first and the features from description below hazard must be considered a quality mining in LCD industry.

• Journal of the Korean Data and Information Science Society
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• v.16 no.2
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• pp.391-399
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• 2005

Consider a stuffing process where sausage-casings are filled with sausage-kneading. One of the most important factors in the stuffing process is weights of stuffed sausages. Sausages weighting above the specified limit are sold in a regular market price for a fixed price, and underfilled sausages are reworked at the expense of reprocessing cost. In this paper, the sausage stuffing process is inspected for improving productivity and quality levels. Several statistical process control tools are suggested by using real data obtained from a Korean Vienna sausage company.

• Journal of Korean Society for Quality Management
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• v.15 no.2
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• pp.20-26
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• 1987

An algorithm for the minimum total process percent defective under marginal costs is presented. Initial process is single series system, which is constructed by k process units, and each process is considered priority. Minimum of total process percent defective for parallel-series system exists when additional process setup costs are larger than marginal costs.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.473-474
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• 2013