• Nuclear Engineering and Technology
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• v.36 no.6
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• pp.540-548
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• 2004

Check valve failure is one of the worst problems in nuclear power plants. Recently, many researches have been based on new technology using accelerometers and ultrasonic and magnetic flux detection have been carried out. Here, we have suggested a method that uses acoustic emission sensors for detecting the failures of check valves through measuring and analyzing backward leakage flow, a system that works without disassembling the check valve. For validating the suggested acoustic emission sensor methodology, we designed a hydraulic test loop with a check valve. We have assumed in this study that check valve failure is caused by disk wear or by the insertion of a foreign object. In addition, we have developed diagnostic algorithms by using a neural network model to identify the type and size of the failure in the check valve. Our results show that the proposed diagnostic algorithm with acoustic emission sensors is a good solution for identifying check valve failure without necessitating any disassembly work.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.9-12
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• 2004

In this paper, a new small sized Lateral Trench Electrode Power MOS was proposed. This new structure, called LTEMOS(Lateral Trench Electrode Power MOS), was based on the conventional lateral power MOS. But the entire electrodes of LTEMOS were placed in trench oxide. The forward blocking voltage of the proposed LTEMOS was improved by 1.5 times with that of the conventional lateral power MOS. The forward blocking voltage of LTEMOS was about 240 V. At the same size, an improvement of the forward blocking voltage of about 1.5 times relative to the conventional MOS was observed by using ISE-TCAD which was used for analyzing device's electrical characteristics. Because all of the electrodes of the proposed device were formed in each trench oxide, the electric field was crowded to trench oxide and punch-through breakdown was occurred, lately.

• Journal of the Korea Society of Computer and Information
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• v.9 no.3
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• pp.27-34
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• 2004

As software developing paradigm has been changing to complicate Web environment, study of complexity becomes vigorous. Yet still it seems that general agreement has not to be reached to architecture or complexity measure of Web application. And so traditional complexity metrics - program size(LOC) and Cyclomatic Complexity can be derived from the source code after implementation. it is not helpful to the early phase of software development life cycle - analysis and design phase. In this study 6 Web projects has been used for deriving applications with possible errors suited by Complexity Indicator. Using 61 programs derived, linear correlation between complexity, number of classes and number of methods has been proposed. As Web application complexity could be estimated before implementation, effort and cost management will be processed more effectively.

• Journal of Korean Institute of Industrial Engineers
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• v.30 no.4
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• pp.338-345
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• 2004

Personal Digital Assistants (PDAs) have become ubiquitous and continued to gain popularity. Since PDAs have some special contexts such as mobility and limited screen size, icons are utilized frequently because icons allow us to do tasks more rapidly and effectively on PDAs like another information appliances. The study presents a cognitive approach to study human factors affecting icon design with multidimensional Scaling (MDS) analysis. In the experiment, a real PDA was used to investigate 29 attributes and2 preference ratings for 22 PDA icons by 20 Korean subjects. As a result, cognitive positioning about icons, attributes, and preference data were arranged on the two dimensional perceptual map. Attributes were grouped by simplicity, universality, activity, complexity, abstraction, static, and alphanumeric time. Subjects preferences were highly related with simplicity attributes group and positive to universality and activity attributes groups. It was also confirmed that there are some icons unfitted to the mental model of Korean. However, when icons are designed for PDAs or similar information appliances to Korean, it should be designed simply and actively with universal image fitted on target users mental model.

• Health Policy and Management
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• v.9 no.3
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• pp.33-52
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• 1999

The purpose of this study is to project the supply and demand for nurses till the year 2012 and to make recommendations for establishment of proper policies regarding them. To predict the supply of nurses. a baseline projection and demographic methods were employed. The derivative demand was used to forecast the demand of nurses. The results of this study provide us with valuable information on nursing manpower planning for the 21th century. Specifically. results indicate that there will be an oversupply of nurses in the near future based on the current productivity. Based on the medical law. there will be an undersupply of nurses till 2002 but an oversupply after that. Thus. the active supply of nurses must be decreased. One way to achieve this would be decreasing the size of training and education. Thus. we recommend that the number of entrances to 4 year programs will be reduced 20% in 2004. and a reduction of 20% by 2005 in 3 year programs. The results of this study suggest the following: First. a manpower bank for nurses who are trying to reenter the market must be established. Second, improvement of education and retraining is needed for the quality control of nurses. Further studies should take into consideration the above factors.

• International Journal of Safety
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• v.5 no.1
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• pp.37-41
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• 2006

The major objective of the statistical analysis about industrial accidents is to determine the safety factors so that it is possible to prevent or decrease the number of future accidents by educating those who work in a given industrial field in safety management. So far, however, there exists no quantitative method for evaluating danger related to industrial accidents. Therefore, as a method for developing quantitative evaluation technique, this study presents feature analysis of industrial accidents in manufacturing field using QUEST algorithm. In order to analyze features of industrial accidents, a retrospective analysis was performed on 10,536 subjects (10,313 injured people, 223 deaths). The sample for this work was chosen from data related to manufacturing businesses during a three-year period ($2002{\sim}2004$) in Korea. This study used AnswerTree of SPSS and the analysis results enabled us to determine the most important variables that can affect injured people such as the occurrence type, the company size, and the time of occurrence. Also, it was found that the classification system adopted in the present study using QUEST algorithm is quite reliable.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.11
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• pp.1271-1284
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• 2011

This study improves the fitness of Air Force winter service uniforms through the development of a shirt pattern drafting method and automatic pattern drafting program for MTM production. A calculation formula is formed through a correlation analysis and regression analysis using Size Korea 2004 3D measurement data after analyzing 4 kinds of existing shirt pattern drafting methods and 3 types of shirt patterns currently used for the Air Force service uniform. The results of this study are as follows: The developed pattern drafting method has 4 parts that use calculated dimensions: neck base width, front interscye, back interscye and scye depth. Other body measuring parts that have a high correlation with calculation parts are inserted into regression analysis as independent variables to create dimension calculation formulas. The result of the final study patterns were better than existing winter service uniforms in nearly all items for the appearance evaluation and motion adaptability evaluations. The method was converted into an automatic pattern drafting program using C++ after the completion of pattern drafting method development.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.7
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• pp.195-201
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• 2021

This study aims to assess the impact of ownership structure of commercial banks on bank credit risk in Vietnam. The authors used the unbalanced table data of 28 commercial banks in the period from 2004 to 2020 with 439 observations. The ratio of loan loss provisioning to loans (CR) is selected as a dependent variable representing credit risk at commercial banks. The regression methods used include: least squares method (OLS), fixed-effect model (FEM), random-effect model (REM) and general least squares method (GLS). The results reveal that, with interaction variable between the ratio of equity to total assets and foreign ownership, the national GDP annual growth rate is negatively associated with credit risk. With the ratio of equity to total assets, the interaction variable between equity and state ownership, and bank size have a significant positive impact on credit risk. In addition, inflation has negligible impact on the credit risk of commercial banks in Vietnam over the research period. The findings of this study suggest that, if foreign-owned banks increase equity capital, there will be a stronger impact on reducing credit risk than other banks. On the other hand, when state-owned commercial banks in Vietnam increase equity, they will have higher credit risk.

• Research in Plant Disease
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• v.12 no.3
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• pp.287-289
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• 2006

Since 2004, a gray mold on Aerides japonicum Lindenb. & Reichb. caused by Botrytis cinerea occurred in a few greenhouses at Goseong and Tongyeong, Gyeongnam, Korea. The disease mainly started on the basal part of leaves, and often lead to severe rots of whole plant. Abundant grayish mycelia and conidial mats were visible on the lesions under a humid conditions. The light gray conidia were one celled and mostly ellipsoid or ovoid in shape. The conidia were $6{\sim}21{\times}4{\sim}13{\mu}m$ in size and conidiophores were $15{\sim}34{\mu}m$ in length. The fungus formed abundant sclerotia on potato-dextrose agar after 18 days incubation at $20^{\circ}C$. The fungus was identified as Botrytis cinerea Persoon: Fries. based on its pathogenicity and mycological characteristics examined in this study. This is the first report of gray mold of Aerides japonicum caused by B. cinerea in Korea.

• The Plant Pathology Journal
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• v.20 no.2
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• pp.127-130
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• 2004

Grapevine leaf roll-associated virus 3 (GLRaV-3) is one of the most important viral diseases of grapevine in the world. In this study, GLRaV-3 Ampelovirus was identi-fied from grapevines in Korea by analyzing viral coat protein size, nucleotide, and amino acid sequences. The molecular weight of viral coat protein from virus-infected in vitro plantlets was determined by western blot using a commercial GLRaV-3 polyclonal antibody. Western blot analysis showed a coat protein of about 43 kDa. RT-PCR product of about 942 bp which encoded the coat protein (CP) gene was amplified with specific primers. When the viruses existed at low titers in the host plant, the dsRNA had very specific template in RT- PCR amplification of fruit tree viruses. Especially, small-scale dsRNA extraction method was very reliable and rapid. Sequence analysis revealed that the CP of the GLRaV-3 Ko consisted of 942 bp nucleotide, which encoded 314 amino acid residues. The CP gene of GLRaV-3 Ko had 98.9% nucleotide sequence and 98.7% amino acid sequence identities with earlier reported GLRaV-3. This is the first report on molecular assay of GLRaV-3 Ampelovirus identified from Korea. The GLRaV-3 Ko CP clone would be very useful for breeding of virus resistant grapevines.