• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.306-310
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• 2014

The purpose of this study is the stability evaluation of a vacuum pump through modal test and rotor dynamics. Eigenvalue was solved by the finite-element method(FEM) using 2D and 3D models, then the modal test result was compared with the FEM result. According to the comparison, the analysis result using the 2D was more accurate than the 3D model. Therefore, rotor dynamics was performed by the 2D model. Campbell diagram and root-locus maps, which were calculated by complex-eigenvalue analysis, were used to evaluate the stability of the rotors of the vacuum pump. And displacement solved by unbalance response analysis was compared with the minimum clearance between two rotors of the vacuum pump. Thus, the vacuum pump is assumed operated under steady state through the evaluation of the rotor dynamics.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.8
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• pp.2088-2102
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• 2009

This study is the result of meta evaluation for the self evaluation of defense R&D programs in Korea. The overall meta evaluation result gained 74.3 points out of 100, so it was evaluated as 'Good'. T- test and one-way ANOVA were used to identify the difference between groups. As a result of difference analysis between groups, some evaluation items showed difference within significance level. From this analysis, it is attempted to identify possible problems and to find out the ways of improvements related to the self evaluation system of defense R&D Programs. The ultimate objective of this study is to manage the programs effectively and improve the reliability and the objectiveness of the defense R&D performances.

• Journal of Advanced Marine Engineering and Technology
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• v.30 no.7
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• pp.782-790
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• 2006

The evaluation systems in SHS(Ship Handling Simulator) or ERS(Engine Room Simulator) give trainees the opportunity to feedback how they responded suggesting them the operation result by scores. If SHS and ERS are integrated each other by network to enable the synchronous training for both deck and engine officers these systems need to include inherently the function of integrated evaluation which produces the evaluation score for the team play of deck and engine officers. The integrated evaluation is effective especially when assessing the responses at emergency situation of ship or the matter of efficiency of ship operation even if assessors feel difficult in editing simulation scenarios for integrated evaluation. This study focuses on the property of integrated evaluation and considerations when editing them. It suggests also a useful procedure to estimate whether a scenario for integrated evaluation is reasonable and balanced or not based on the analysis in the proprieties and reasonabilities which are to be prepared by assessors before testing trainees or examinees.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.5
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• pp.129-144
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• 2012

This study was conducted to understand the community characteristics of benthic macroinvertebrates according to Growth Environment at 6 Palustrine Wetlands in a rural area. As growth environment factors, size, water depth, water inlet and water outlet, land-use and water environment was analyzed. Two years' quantitative collection of benthic macroinvertebrate was carried out, and it executed community analysis and ESB index calculation and also carried out twinspan, MDS and correlation analysis. As a result, the collected benthic macroinvertebrate was 1254 individuals with 3 Phylums, 6 Classes, 14 Orders, 35 Families, 52 Genera and 61 Species. Odonata and Coenagreionidae had the highest species and individuals. Dominance Index was 0.252~0.698, Diversity Index was 1.661~2.902, Evenness Index was 0.414~0.724, and Species Richness Index was 1.990~6.224. As a result of community analysis, when correlation analysis was executed, Dominance Index had the opposite tendency with Diversity Index and Evenness Index, which had the same tendency with the previous studies. When ESB Index was calculated, Grade 2 (polluted) had the highest species with 48 species (78.7%). It is determined from the Environmental quality evaluation and saprobity evaluation result according to ESB index that there is a need to revise environmental evaluation system more specifically. As a result of MDS analysis, the subject spots A and D had the highest similarity, and the subject spot E and D had a relatively high similarity. The life environment that is the closest related with species diversity is estimated by the land-use. As for number of Individual, it seems to have the closest relation with inlet, which is to be determined as a characteristics of Palustrine Wetland. Through such investigation, this study is expected to be utilized for various types of habitats including ecological pond and to be utilized for the increase of species diversity in rural areas.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.2
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• pp.362-372
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• 1996

Recently, need for the development of the quantification of subjective evaluation is growing for the production of high-touch and high-tech textile products. In this study, Fuzzy theory is utilized for the evaluation of the wear comfort of the various blouses. Result of a new evaluation method and factor scores, validity of the new evalution technique adopted fuzzy theory was crosschecked with the results of fator analysis and factor scores. As results, fuzzy theory was proved to be adequate methodology to objectify the subjective evaluation of the adequacy of clothing which is worn. When DUNCAN'S multiple comparion among median of the fuzzy composite score were compared with the results of factor score, the sensitivity of the test methods tends to increase. Therefore, it is suggested that fuzzy weighted checklist is an alternative evaluation scale for the subjective comparison of the textile products. In addition, individual median of fuzzy composite score value should be treated by statistical for the sensitive analysis of subjective evalution.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.1
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• pp.1-10
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• 2018

Current evaluation practices for IT projects suffer from several problems, which include the difficulty of self-explanation for the evaluation results and the improperly scaled scoring system. This study aims to develop a methodology of opinion mining to extract key factors for the causal relationship analysis and to assess the feasibility of quantifying evaluation scores from text comments using opinion mining based on big data analysis. The research has been performed on the domain of publicly procured IT proposal evaluations, which are managed by the National Procurement Service. Around 10,000 sets of comments and evaluation scores have been gathered, most of which are in the form of digital data but some in paper documents. Thus, more refined form of text has been prepared using various tools. From them, keywords for factors and polarity indicators have been extracted, and experts on this domain have selected some of them as the key factors and indicators. Also, those keywords have been grouped into into dimensions. Causal relationship between keyword or dimension factors and evaluation scores were analyzed based on the two research models-a keyword-based model and a dimension-based model, using the correlation analysis and the regression analysis. The results show that keyword factors such as planning, strategy, technology and PM mostly affects the evaluation result and that the keywords are more appropriate forms of factors for causal relationship analysis than the dimensions. Also, it can be asserted from the analysis that evaluation scores can be composed or calculated from the unstructured text comments using opinion mining, when a comprehensive dictionary of polarity for Korean language can be provided. This study may contribute to the area of big data-based evaluation methodology and opinion mining for IT proposal evaluation, leading to a more reliable and effective IT proposal evaluation method.

• Environmental Analysis Health and Toxicology
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• v.25 no.3
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• pp.187-195
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• 2010

Nanotechnology is the fastest growing area in scientific research and it has important applications in a wide variety of fields. Nevertheless, consumers encountered this new technology without any identification of risks and benefits. Also until now, there are no specific safety evaluation methods for nanotechnology. For this reason, we studied risk communication strategy for nanotechnology to prepare its application in commercialized products on public. A survey was conducted to identify the differences in perception between public (N=110) and expert (N=37) toward applied nanotechnology in food, drugs and cosmetic products. The survey results were used to draw up a risk cognitive map which was introduced by Paul Slovic, and the perception level of public and expert on nanotechnology was evaluated. As a result of the survey, public recognized nanotechnology as "unknown but low dread" risk factor, but expert recognized it as "unknown and high dread" risk factor. These results indicate that there are perception differences between two groups. Several risk communication strategies are reported including care, consensus and risk communication. In the case of nanotechnology, it contains both risks and benefits. Considering the nature of nanotechnology, the "consensus communication" which informs consumers about risks and benefits of issues is the most appropriate strategy.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.12
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• pp.1112-1119
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• 2011

The goal of this study is the stability evaluation of a vacuum pump through modal test and rotor dynamics. Roots type vacuum pump, which is a dry vacuum pump, is necessary for the manufacturing process of the semiconductor and the display. Eigenvalue was solved by the finite-element method(FEM) using 2D and 3D models, then the modal test result was compared with the FEM result. According to the comparison, the analysis result using the 2D was more accurate than the 3D model. Therefore, rotor dynamics was performed by the 2D model. Campbell diagram and root-locus maps, which were calculated by complex-eigenvalue analysis, were used to evaluate the stability of the rotors of the vacuum pump. And displacement solved by unbalance response analysis was compared with the minimum clearance between two rotors of the vacuum pump. Thus, the vacuum pump is assumed operated under steady state through the evaluation of the rotor dynamics.

• Communications for Statistical Applications and Methods
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• v.12 no.3
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• pp.589-601
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• 2005

Student evaluation of university teaching is a common tool for measuring the educational contribution of a professor and improving the quality of classes. There, however, exist external factors in the beyond of control of a instructor, which affect the result of Student's rating to prevent practical use of evaluation for administrative purpose. This paper investigates the factors that spoil the validity and the reliability of student evaluation and proposes a method to control the effect by the statistical analysis of evaluation data of Jeonju University for two years.

• Journal of Information Technology Services
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• v.16 no.1
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• pp.41-53
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• 2017

Recently, due to the economic recession and increase of ITO (IT Outsourcing), bidding in software industry has been recognized as more competitive and the importance of software bid evaluation for corporate selection is being increased. This study aims to analyze and prioritize influential factors in the software bid evaluation criteria which is adopted as the main evaluation model of national software businesses by Ministry of Science. The priority was developed by AHP (Analytic Hierarchy Process) through pair-wise comparison. For the analysis, this study developed analysis model for AHP and conducted survey of experts who have work experience for more than 10 years in the IT industry. As the result of analysis, weighted factors in the evaluation criteria were deduced and differences of priority factors between purchaser and bidder were investigated. The analysis showed differences of view point in the bidding process. With these results, this study suggests how to write a proposal strategically and effectively in perspective of the purchaser. It is expected that priority factors will be adopted in strategic proposals in both bidder and purchaser. For purchaser, the priority will be adopted to select reliable bidder. So, we expect that the priority factors will be used to get more values for both bidder and purchaser in their business atmosphere.