• Journal of Engineering Education Research
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• v.15 no.4
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• pp.35-40
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• 2012

This study presents an analysis of the current situation (management, approach, adjustment, transportation, and others) of teaching portfolio by examining the teaching portfolio managers (staffs, researchers, teaching assistants, etc.) of 6 universities in the southeast of Korea. The rationale for the study focus is that the existing teaching portfolio either suffers a problem in the transportation, approach, adjustment and/or management or is likely to raise a problem in the future. In order to solve this problem, this study builds a web-based e-teaching portfolio. According to the analysis results, the engineering education system was established in all 6 universities (Ed- note that '6 universities' has already been specified as the study sample). The teaching portfolio was partially digitalized in this system, despite some problems of converting analog data into digital data, which induced difficulties in constructing the overall e-teaching portfolio. Therefore, this study focused on constructing an e-teaching portfolio without developing any additional system by using the existing system positively, and also on determining the appropriate components among the existing teaching portfolio components. Accordingly, in order to convert the analog data into the digital data required for this study, we used a digital camera as the conversion device and converted the teaching portfolio components into those appropriate for the e-teaching portfolio. Finally, we constructed an existing system appropriate for the e-teaching portfolio by using these devices and components.

• The Journal of Information Systems
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• v.28 no.3
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• pp.203-225
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• 2019

Purpose The purpose of this study is to empirically verify an ePortfolio success model which shows the structural causal relationships among the basic modeling constructs. We developed the success model based on DeLone and Mclean(2003) from IS perspective and on Balaban et al(2013) from ePortfolio perspective. And we are focused on the success of ePortfolio system designed for college students and professors. Design/methodology/approach Structural equation modeling techniques were applied to data collected 375 users of the ePortfolio system, K-Folio, at least one semester during one academic year. The structural model was analyzed using a Lisrel 8.54 statistical program. Findings The followings are the findings of the study. First, the constructs of IS success model are well applied to ePortfolio for college education. Second, the proposed model which has direct causal relationships from ePortfolio's quality to performance is more significant than the D&M and Balaban's model(2013). Third, the information quality among ePortfolio quality constructs does not have effect on system usability and performance. It means that information contents' quality issued by professor or system manager is not satisfied with the students yet. Finally, by using indirect analysis of structural equation model, we found that the ePortfolio operation manager should focus on ensuring system maintenance activities and providing fast and accurate services for improving ePortfolio performance.

• Journal of the Korea Society of Computer and Information
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• v.13 no.5
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• pp.37-44
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• 2008

In recent years, e-portfolios and webfolios have been highly vaunted as the next great innovation in education. Hundreds of academic institutions are variously studying, using, or innovating e-portfolio systems. Despite the presumed goodness of e-portfolios, some problems remain. In this paper we review the existing e-portfolio management systems, and propose and implement a novel system to overcome the limits of the existing e-portfolio management systems. The propose e-portfolio management system has a structure of competition with others. All of the student's activities are accomplished and preserved within the same personal web space like a blog with mutual engagements and recommendations.

• Korean Management Science Review
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• v.25 no.1
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• pp.1-9
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• 2008

This paper investigates the R&D project portfolio selection problem. Despite its importance and impact on real world projects, there exist few practical techniques that help construct an non-dominated portfolio for a decision makers satisfaction. One of the difficulties constructing the portfolio is that such project portfolio problem is, in nature, a multi-attribute decision-making problem, which is an NP-hard class problem. This paper investigates the R&D project portfolio selection problem. Despite its importance and impact on real world projects, there exist few practical techniques that help construct an non-dominated portfolio for a decision makers satisfaction. One of the difficulties constructing the portfolio is that such project portfolio problem is, in nature, a multi-attribute decision-making problem, which is an NP-hard class problem. In order to obtain the non-dominated portfolio that a decision maker or a user is satisfied with, we devise a user-interface algorithm, in that the user provides the maximum/minimum input values for each project attribute. Then the system searches the non-dominated portfolio that satisfies all the given constraints if such a portfolio exists. The process that the user adjusts the maximum/minimum values on the basis of the portfolio found continues repeatedly until the user is optimally satisfied with. We illustrate the algorithm proposed, and the computational results show the efficacy of our procedure.

• Journal of The Korean Association For Science Education
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• v.20 no.1
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• pp.183-192
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• 2000

The purpose of this study is to investigate the effects of portfolio system on science teaching efficacy beliefs. From Chongju National University of Education, 83 subjects were selected. All of them are college sophomores, and 5 of them are males. The portfolio system developed by the researcher had been administered during the 1st semester of 1999. Korean Science Teaching Efficacy Beliefs Instrument (K-STEBI) was administered before and after portfolio instruction. Some parts of students portfolios were analyzed qualitatively in terms of elementary science teaching confidence. After portfolio instruction, students' science teaching efficacy beliefs increased statistically meaningfully. Elementary science teaching confidence and positive attitudes toward portfolio system also showed marked increase. Portfolio system seems to be effective in fostering pre-service elementary teachers' science teaching efficacy beliefs, and be a powerful tool for teacher education.

• The Journal of the Korea Contents Association
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• v.7 no.12
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• pp.83-94
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• 2007

The portfolio can be used as a methodology supporting the learning of constructivism. Recently, the use of portfolios has been increased gradually in the education field, but a study on the current state analysis and design direction of portfolios leaves much to be desired. In this paper, we analyze statistical data on the portfolio application of teachers in domestic elementary, middle, and high school. We also propose a design direction of e-portfolio needed in the society of knowledge information based on this analysis. The results of research show that the following problems will be improved: understanding portfolio, analyzing the current state according to the types of portfolio application, designing a distinguished system according to the level of school, expanding education of teachers with high career, and developing a guide helper. The design of total system that combines the learning and evaluation is needed to improve a problem that spends lots of time to make portfolio, and operates temporally and formally achievement evaluation. In addition, the design of e-portfolio supporting efficiently interaction and self-directed teaming is required.

• International Journal of Advanced Culture Technology
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• v.10 no.3
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• pp.220-225
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• 2022

The purpose of this study is to develop an e-teaching portfolio to perform a teaching portfolio of an instructor on the web. I order to carry out this study, an initial model of the e-teaching portfolio was developed through systematic literature review, and the final e-teaching portfolio was developed by selecting and applying five students, then modifying and supplementing them. The study period was from May 1 to May 20, 2022. As a result of the study, the components of the finally developed e-teaching portfolio are Step 1: Understanding oneself, Step 2: Goal setting, Step 3: Learning strategy, Step 4: Self-check. In conclusion, the program developed through this study is a convenient function that can process everything in one place by connecting the fragmented teaching results, and the developed e-teaching portfolio can promote interaction between individuals by building a community. It has possible characteristics. In order to systematically activate the e-teaching portfolio developed through this study, it is necessary to establish an online management system for systematic operation. Furthermore, an institutional device is needed to guarantee the result of the developed e-teaching portfolio. In order to continuously manage the quality of the teaching portfolio, extrinsic rewards that stimulate the instructor's intrinsic motivation should be provided.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.4
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• pp.63-73
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• 2023

This study explores modern portfolio theory by integrating the Black-Litterman portfolio with time-series clustering, specificially emphasizing K-shape clustering methodology. K-shape clustering enables grouping time-series data effectively, enhancing the ability to plan and manage investments in stock markets when combined with the Black-Litterman portfolio. Based on the patterns of stock markets, the objective is to understand the relationship between past market data and planning future investment strategies through backtesting. Additionally, by examining diverse learning and investment periods, it is identified optimal strategies to boost portfolio returns while efficiently managing associated risks. For comparative analysis, traditional Markowitz portfolio is also assessed in conjunction with clustering techniques utilizing K-Means and K-Means with Dynamic Time Warping. It is suggested that the combination of K-shape and the Black-Litterman model significantly enhances portfolio optimization in the stock market, providing valuable insights for making stable portfolio investment decisions. The achieved sharpe ratio of 0.722 indicates a significantly higher performance when compared to other benchmarks, underlining the effectiveness of the K-shape and Black-Litterman integration in portfolio optimization.

• 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.

• Journal of The Korean Association For Science Education
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• v.21 no.3
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• pp.529-536
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• 2001

The purpose of the research is to investigate the effects of a portfolio system on students' socio-psychological classroom environments in elementary science class. Two schools were selected from a metropolitan area, a city, and one school from a rural area in central Korea. Two fifth-grade classes were sampled from each school selected, and one class is assigned to experimental group and the other to control group, respectively. The total number of participants of the study is 399. Portfolio system was administered to experimental group, and conventional teaching to control group for two and half month. WIHIC, an inventory to measure socio-psychological classroom environment, was administered as a pre- and post-test. Experimental group gained statistically higher scores on WIHIC after administering portfolio system. They showed more positive perceptions on sub-areas of WIHIC such as teacher support, task orientation, and equity. There is interaction between region and group: the effects of the portfolio system is highest in rural area, lowest in metropolitan area, and the city in between. Portfolio system have positive effects on students' socio-psychological classroom environments. Enhanced socio-psychological classroom environments is expected to contribute to positive self-concept, higher science achievements, and self-directed learning.