• Korean Journal of Construction Engineering and Management
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• v.19 no.2
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• pp.3-14
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• 2018

The system to appraise the execution capabilities of construction companies had been began as the Construction Contract Restriction System in 1958, was changed as the Construction Subcontract Restriction System in 1961, and finally has been operated as the Appraisal and Public Announcement of Execution Capacity (APAEC) from 1996. The APAEC system has been utilized as a firm and unique tool for assessing the execution capacities of construction companies despite many problems and continuous system changes. In spite of numerous studies to improve the APAEC system, however, efforts to analyze the system from the empirical point of view were insufficient. In this study, we analyze the status of APAEC system through analyzing correlations among assessment results of the APAEC, earned values of construction works, construction management performance indexes, and macroeconomic indexes for the past 10 years from 2007 to 2016. As a result of the analysis, it was found that Appraisal Value of Execution Capacity (AVEC) is excessively inflated in engineering and landscaping areas compared to Earned Value of Construction Work (EVCW) and the correlations between the AVECs and EVECs are not high in the areas of engineering, industrial equipment, and landscaping. In addition, technical appraisal values are excessively inflated in engineering and landscaping areas and correlations between AVEC and its components are high in the areas of engineering & building, industrial equipment, and large companies, but low in the areas of engineering, building, landscaping, and small and medium companies. Finally, the concentration of the AVEC is intensifying more and more and the concentration deteriorates construction management performance indexes and macroeconomic indexes. If we continuously improve the APAEC system based on the implications derived in this study, the APAEC system will be able to maintain it's position of a firm and unique means to access the execution capacities of construction companies.

• 대한공업교육학회지
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• v.33 no.2
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• pp.97-119
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• 2008

The purpose of this research is to clarify the elements of the function of the role of industrial high schools that its experts perceived. The content of this research is verify the function element required for the performance of the role of specialized education through content validity ratio(CVR). This research adopted the method of literature research and Delphi method, which is to collect and come to an agreement of the opinions of the 26 research panels. The first round is constructed by the semi-constructed questionnaire for the analysis of the opinions of the panels by inductive method. The second round is to categorize the result of the first one into 7 domains, and asked each category by Likert's 5 scale checklists, and statistically analyzed mean, medium, standard deviation, and quartile. The third round is to statistically analyze Mean, standard deviation, medium, and validity ratio(CVR) to reassure the opinions of the panels on the basis of the result of the first one. The categorized contents of the function required for the performance of the specialized education in this research is 'in-service visit and in-service training', 'licence acquiring education', 'employment counseling and job employment information', 'custom-made education connected with industry', 'career education' and 'enhancement of basic career competency'. The panels are divided into professors, teachers, professionals, and policy administrators, and they verified the validity rate of the function role and priority of emphasis. The result showed that the tendency of the education is converting from physical function-centered education to education of emotional attitude and competence of thought.

• Journal of radiological science and technology
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• v.38 no.4
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• pp.365-374
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• 2015

The regular quality assurance (RQA) of X-ray images is essential for maintaining a high accuracy of diagnosis. This study was to evaluate the modulation transfer function (MTF), the noise power spectrum (NPS), and the detective quantum efficiency (DQE) of a computed radiography (CR) system for various periods of use from 2006 to 2015. We measured the pre-sampling MTF using the edge method and RQA 5 based on commission standard international electro-technical commission (IEC). The spatial frequencies corresponding to the 50% MTF for the CR systems in 2006, 2009, 2012 and 2015 were 1.54, 1.14, 1.12, and $1.38mm^{-1}$, respectively and the10% MTF for 2006, 2009, 2012, and 2015 were 2.68, 2.44, 2.44, and $2.46mm^{-1}$, respectively. In the NPS results, the CR systems showed the best noise distribution in 2006, and with the quality of distributions in the order of 2015, 2009, and 2012. At peak DQE and DQE at $1mm^{-1}$, the CR systems showed the best efficiency in 2006, and showed better efficiency in order of 2015, 2009, and 2012. Because the eraser lamp in the CR systems was replaced, the image quality in 2015 was superior to those in 2009 and 2012. This study can be incorporated into used in clinical QA requiring performance and evaluation of the performance of the CR systems.

• Journal of Intelligence and Information Systems
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• v.20 no.2
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• pp.59-71
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• 2014

System trading is becoming more popular among Korean traders recently. System traders use automatic order systems based on the system generated buy and sell signals. These signals are generated from the predetermined entry and exit rules that were coded by system traders. Most researches on system trading have focused on designing profitable entry and exit rules using technical indicators. However, market conditions, strategy characteristics, and money management also have influences on the profitability of the system trading. Unexpected price deviations from the predetermined trading rules can incur large losses to system traders. Therefore, most professional traders use strategy portfolios rather than only one strategy. Building a good strategy portfolio is important because trading performance depends on strategy portfolios. Despite of the importance of designing strategy portfolio, rule of thumb methods have been used to select trading strategies. In this study, we propose a SVM-based strategy portfolio management system. SVM were introduced by Vapnik and is known to be effective for data mining area. It can build good portfolios within a very short period of time. Since SVM minimizes structural risks, it is best suitable for the futures trading market in which prices do not move exactly the same as the past. Our system trading strategies include moving-average cross system, MACD cross system, trend-following system, buy dips and sell rallies system, DMI system, Keltner channel system, Bollinger Bands system, and Fibonacci system. These strategies are well known and frequently being used by many professional traders. We program these strategies for generating automated system signals for entry and exit. We propose SVM-based strategies selection system and portfolio construction and order routing system. Strategies selection system is a portfolio training system. It generates training data and makes SVM model using optimal portfolio. We make $m{\times}n$ data matrix by dividing KOSPI 200 index futures data with a same period. Optimal strategy portfolio is derived from analyzing each strategy performance. SVM model is generated based on this data and optimal strategy portfolio. We use 80% of the data for training and the remaining 20% is used for testing the strategy. For training, we select two strategies which show the highest profit in the next day. Selection method 1 selects two strategies and method 2 selects maximum two strategies which show profit more than 0.1 point. We use one-against-all method which has fast processing time. We analyse the daily data of KOSPI 200 index futures contracts from January 1990 to November 2011. Price change rates for 50 days are used as SVM input data. The training period is from January 1990 to March 2007 and the test period is from March 2007 to November 2011. We suggest three benchmark strategies portfolio. BM1 holds two contracts of KOSPI 200 index futures for testing period. BM2 is constructed as two strategies which show the largest cumulative profit during 30 days before testing starts. BM3 has two strategies which show best profits during testing period. Trading cost include brokerage commission cost and slippage cost. The proposed strategy portfolio management system shows profit more than double of the benchmark portfolios. BM1 shows 103.44 point profit, BM2 shows 488.61 point profit, and BM3 shows 502.41 point profit after deducting trading cost. The best benchmark is the portfolio of the two best profit strategies during the test period. The proposed system 1 shows 706.22 point profit and proposed system 2 shows 768.95 point profit after deducting trading cost. The equity curves for the entire period show stable pattern. With higher profit, this suggests a good trading direction for system traders. We can make more stable and more profitable portfolios if we add money management module to the system.

• Management & Information Systems Review
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• v.36 no.5
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• pp.1-26
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• 2017

In the meantime, research on corporate informatization focuses on the completeness of information technology itself and its financial effects, so there is insufficient research on whether information technology can support business strategy. It is necessary to verify whether the management strategy implementation of the company can be led through the informatization of the enterprise and the relation between the main mechanism factors and the informatization performance. In this study, what a mechanism factor is applied in the process of result creation of informatization from three mechanism perspectives such as selecting mechanism, learning mechanism and coordinating mechanism with cases of representative domestic IT company and what an importance mechanism factors have been ascertained. This study results in 8 propositions. For a main agent of companies, securement of information capability of organizations has been selected to realize informatization results and investment of informatization has been selected to solve organizational decentralization problems as the most important factor. Additionally, as competition in the industry gets fierce, investment on informatization has been changed to a utility way of implementation of strategies and decision on investment has been made through the official process and information technology. Differentiated company capability has been made based on acquisition of technical knowledge and company information has been expanded to its whole employees through the information system. Also, informatization change management and outside subcontractor management have been acknowledged as an important adjustment factor of company. The first implication of this study is that since case studies on mechanism factors that preceding studies on informatization results did not empirically cover have directly been dealt with based on experiences of executives in charge of business and in charge of informatization, this study can provide practical views about factors that should be mainly managed for informatization results of IT companies. Secondly, since ser-M framework has been applied for IT companies for the first time, this study can academically contribute to companies in other fields about main mechanism factors for result creation of informatization based on deeper understanding and empirical cases.

• 대한공업교육학회지
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• v.41 no.1
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• pp.68-87
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• 2016

This research conducted a survey for total 166 teachers of schools so as to analyze validity and satisfaction for performance objectives of SMB administration subsidy the HRDP and the CEP in Specialized High School. The results of research are as follows. First, teachers recognize that purpose of HRDP is to expand employment of specialized high school and provide human resource of SMB. And, they recognize that HRDP is important to improve school outcomes and makes a positive effect on the improvement of school outcomes. Second, teachers recognize that objectives of HRDP are improvement of student's understanding for SMB, improvement of teacher's understanding for SMB, improvement of SMB's understanding of school, cultivation of student's occupational view, systematization of career guiding program based on employment process, strengthening of industry-academia cooperation education, improvement of the level of student's skill, fulfillment of workplace experience and practice focusing workplace learning, training of customized human resource for SMB, improvement of student's adaptation to the workplace, improvement of employment rate for SMB, expansion of job opportunities for students with SMB, preparation of the base of connection between school and SMB, publicity of school, expansion of opportunities to cooperate between SMB and school, establishment of cooperative system among industrial association and school, introduction and operation of the employment connective model for joint education and employment, strengthening of field professionalism of teachers. However, satisfaction for the achievement of objectives of HRDP except for strengthening of industry-academia cooperation education and improvement of employment rate for SMB is relatively lower than the validity. Third, teachers in charge of human resource training business of middle and small sized company's specialized high school recognize that objectives of CEP are expansion of job opportunities for students with SMB, excavation of good-quality SMB, expansion of opportunities to cooperate between SMB and school, fulfillment of workplace learning, improvement of student's major foundation and in-depth skill, improvement of literacy, math, teamwork and communication abilities for students' job performance, improvement of student's working attitude and student's proper career exploration decision. However, satisfaction for achievement of objectives of CEP is relatively lower than the validity.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.2
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• pp.1-13
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• 2019

As a way to find new and innovative technologies, many companies have invested in and acquired skilled startups. Because startups are usually small in size and have a small history of past business experience, there are many risks involved in acquiring them as they have limited technical skills and business feasibility verification methods. Thus, venture capital plays an important role in discovering and investing competitive startups. While Independent Venture Capital generally values financial returns, Corporate Venture Capital, which plays investment roles in the firm, values business synergies with the parent company from a strategic perspective. In an industry sector where development of technology is rapid and whether new technology is held determines a company's competitiveness, existing companies incorporate startups with innovative technologies into their investment portfolios, collaborate together, and take over for comprehensive cooperation. In addition, new investments and acquisitions are carried out through the management of portfolio companies to obtain and utilize industry information. In this paper, major U.S. companies listed in the U.S. verified their investment activities through corporate venture capital and their impact on parent companies and startups through regression, while the parent company's acquisition performance was analyzed through an event study based on a stock price analysis. The criteria for startup were defined as companies with less than 12 years of experience, and the analysis showed that the parent companies with corporate venture capital with a larger number of investments actively take over startups. In addition, increasing corporate venture capital's financial investment activities shows a negative impact on the parent companies' acquisition activities, and the acquisition performance increased when the parent companies took over startups in its portfolio.

• Journal of Intelligence and Information Systems
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• v.28 no.2
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• pp.237-262
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• 2022

There has been a growing interest in IPOs (Initial Public Offerings) due to the profitable returns that IPO stocks can offer to investors. However, IPOs can be speculative investments that may involve substantial risk as well because shares tend to be volatile, and the supply of IPO shares is often highly limited. Therefore, it is crucially important that IPO investors are well informed of the issuing firms and the market before deciding whether to invest or not. Unlike institutional investors, individual investors are at a disadvantage since there are few opportunities for individuals to obtain information on the IPOs. In this regard, the purpose of this study is to provide individual investors with the information they may consider when making an IPO investment decision. This study presents a model that uses machine learning and text analysis to predict whether an IPO stock price would move up or down after the first 5 trading days. Our sample includes 691 Korean IPOs from June 2009 to December 2020. The input variables for the prediction are three tone variables created from IPO prospectuses and quantitative variables that are either firm-specific, issue-specific, or market-specific. The three prospectus tone variables indicate the percentage of positive, neutral, and negative sentences in a prospectus, respectively. We considered only the sentences in the Risk Factors section of a prospectus for the tone analysis in this study. All sentences were classified into 'positive', 'neutral', and 'negative' via text analysis using TF-IDF (Term Frequency - Inverse Document Frequency). Measuring the tone of each sentence was conducted by machine learning instead of a lexicon-based approach due to the lack of sentiment dictionaries suitable for Korean text analysis in the context of finance. For this reason, the training set was created by randomly selecting 10% of the sentences from each prospectus, and the sentence classification task on the training set was performed after reading each sentence in person. Then, based on the training set, a Support Vector Machine model was utilized to predict the tone of sentences in the test set. Finally, the machine learning model calculated the percentages of positive, neutral, and negative sentences in each prospectus. To predict the price movement of an IPO stock, four different machine learning techniques were applied: Logistic Regression, Random Forest, Support Vector Machine, and Artificial Neural Network. According to the results, models that use quantitative variables using technical analysis and prospectus tone variables together show higher accuracy than models that use only quantitative variables. More specifically, the prediction accuracy was improved by 1.45% points in the Random Forest model, 4.34% points in the Artificial Neural Network model, and 5.07% points in the Support Vector Machine model. After testing the performance of these machine learning techniques, the Artificial Neural Network model using both quantitative variables and prospectus tone variables was the model with the highest prediction accuracy rate, which was 61.59%. The results indicate that the tone of a prospectus is a significant factor in predicting the price movement of an IPO stock. In addition, the McNemar test was used to verify the statistically significant difference between the models. The model using only quantitative variables and the model using both the quantitative variables and the prospectus tone variables were compared, and it was confirmed that the predictive performance improved significantly at a 1% significance level.

• (The) Research of the performance art and culture
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• no.19
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• pp.161-190
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• 2009

This study presents matters of how to analyse the dance of artistic form on the course of transforming folk art to be separated from leisure to become the art form. In particular, the traditional art of dance in Korea has been of collective act like dureh, rather than of individual art, that it had to choose the repeated style of same form and rhythm. In this respect, before it can be said that the dance in its own form became more sophisticated and adopted the artistic segment in the time of modernisation, it is viewed that in the very heart of folk dance there was sufficient ability of artistic material to seek its own right. In this regard, the artistic transformation of seoljanggo nori into seoljanggo dance is an art form which is found in Korea, and expressing rhythm and playfulness is evident and sought attention. Therefore this study puts its importance in analysing how, in the aspect of the course of life of traditional arts, dance is formed in its own right and developed a form of art from fun entertainment. I have chosen, among them, seoljanggo, which used to be a form of fun entertainment and later transformed into a form of art on stage, in particular LeeGyeongh wa seoljanggo dance which maintains the style of Honam Udo farmers' music, and tried to read the text from it. It has resulted in that, Lee Gyeonghwa seoljanggo dance did a new try on tradition, in its development of expressing art through dance and onto more technical sophistication, found in the style of tune and choreography fused into its distinctive form. The art of traditional dance concerns here that seoljanggo has changed from agrarian entertainment to modern stage art, which shows how tradition can be adopted to the contemporary cultural life or to be reinvented to the needs of the aesthetic style that the current society consumes. Thus, it is necessary to think about its role in education and to represent cultural creativity from local developments.

• Journal of the Society of Disaster Information
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• v.19 no.4
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• pp.976-983
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• 2023

Purpose: The dynamic behavior of a bridge structure under seismic loading depends on many uncertainties, such as the nature of the seismic waves and the material and geometric properties. However, not all uncertainties have a significant impact on the dynamic behavior of a bridge structure. Since probabilistic seismic performance evaluation considering even low-impact uncertainties is computationally expensive, the uncertainties should be identified by considering their impact on the dynamic behavior of the bridge. Therefore, in this study, a global sensitivity analysis was performed to identify the main parameters affecting the dynamic behavior of bridges with I-curved girders. Method: Considering the uncertainty of the earthquake and the material and geometric uncertainty of the curved bridge, a finite element analysis was performed, and a surrogate model was developed based on the analysis results. The surrogate model was evaluated using performance metrics such as coefficient of determination, and finally, a global sensitivity analysis based on the surrogate model was performed. Result: The uncertainty factors that have the greatest influence on the stress response of the I-curved girder under seismic loading are the peak ground acceleration (PGA), the height of the bridge (h), and the yield stress of the steel (fy). The main effect sensitivity indices of PGA, h, and fy were found to be 0.7096, 0.0839, and 0.0352, respectively, and the total sensitivity indices were found to be 0.9459, 0.1297, and 0.0678, respectively. Conclusion: The stress response of the I-shaped curved girder is dominated by the uncertainty of the input motions and is strongly influenced by the interaction effect between each uncertainty factor. Therefore, additional sensitivity analysis of the uncertainty of the input motions, such as the number of input motions and the intensity measure(IM), and a global sensitivity analysis considering the structural uncertainty, such as the number and curvature of the curved girders, are required.