• 한국경영과학회지
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• 제39권2호
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• pp.83-95
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• 2014

In this paper, we develop a portfolio selection model that can be used to invest in markets with margin requirements such as the foreign exchange market. An investment algorithm to implement the proposed portfolio selection model based on objective historical data is also presented. We further conduct empirical analysis on the performance of a hypothetical investment in the foreign exchange market, using the proposed portfolio selection model and investment algorithm. Using 7 currency pairs that recorded the highest trading volume in the foreign exchange market during the most recent 10 years, we compare the performance of 1) the Dollar Index, 2) a 1/N Portfolio which equally allocates capital to all N assets considered for investment, and 3) a hypothetical investment portfolio selected and managed according to the portfolio selection model and investment algorithm proposed in this paper. Performance is compared in terms of accumulated returns and Sharpe ratios for the 10-year period from January 2003 to December 2012. The results show that the hypothetical investment portfolio outperforms both benchmarks, with superior performance especially during the period following financial crisis. Overall, this paper suggests that a mathematical approach for selecting and managing an optimal investment portfolio based on objective data can achieve outstanding performance in the foreign exchange market.

• The Journal of Asian Finance, Economics and Business
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• 제1권2호
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• pp.31-37
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• 2014

The portfolio selection is one of the most important and vital decisions that a real or legal person, who invests in stock market, should make. The main purpose of this article is the determination of the optimal portfolio with regard to relations among stock returns of companies which are active in Tehran's stock market. For achieving this goal, weekly statistics of company's stocks since Farvardin 1389 until Esfand 1390, has been used. For analyzing statistics and information and examination of stocks of companies which has change in returns, factors analysis approach and clustering analysis has been used (FC approach). With using multivariate analysis and with the aim of reducing the unsystematic risk, a financial portfoliois formed. At last but not least, results of choosing the optimal portfolio rather than randomly choosing a portfolio are given.

• 한국기술혁신학회:학술대회논문집
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• 한국기술혁신학회 2017년도 춘계학술대회 논문집
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• pp.357-391
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• 2017

In this study, we suggest a new perspective on the linkage between alliance portfolio diversity and innovation performance based on a contingency approach. Using a longitudinal data set on alliance portfolios and patents of 182 firms in the U.S. manufacturing industries, we examined that alliance portfolio diversity has a U-shaped relationship with firm-level innovation. Internal value creation capabilities in terms of routine and ability are found to moderate the relationship between alliance portfolio diversity and innovation performance: Organizational search routine strengthens the relationship of alliance portfolio diversity and innovation performance while technological capabilities weaken and flip the relationship.

• 정보학연구
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• 제9권3호
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• pp.77-89
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• 2006

The event study analyzes returns around event date at a time. Event study provides estimation periods and cumulative returns. Stock split announcements are generally associated with positive abnormal returns. It is important to investigate the responses of stocks to new information contained in the announcements of stock splits. So It is important to study the long term performance in the case of Stock Split. This Study forced to two approach method in evaluating the performance, the event time portfolio approach and calendar time portfolio approach. The event time portfolio approach exists the CAR model, BHAR model and WR model. And the calendar time portfolio approach has the 3 factor model, 4 factor model, CTAR model, and RATS model.

• 수산해양교육연구
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• 제20권2호
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• pp.236-248
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• 2008

This study has explored the elements of e-teaching portfolio for enhancing teaching expertise in higher education. This study is carried out through the literature review and expert's focus group interview. As the result of this study, seven elements of e-teaching portfolio for enhancing teaching expertise in higher education have been found. First, 'personal background' include curriculum vitae, course responsibility, and other educational activities. Second, 'teaching philosophy' include the principals on teaching and learning, statements of teaching philosophy. Third, 'learning environment' include the characteristics of students, the previous learning contents, and physical environment. Forth, 'course contents and methods' include teaching strategies and instructional materials, Fifth, 'instructional evaluation' includes the principals of evaluation and the examples of learning outcomes. Sixth, 'endeavor for improvement of instruction' include evidence of activity for teaching improvement and instruction feedback from peer and students. And e-teaching portfolio also includes research career and awards history element.

• 아동학회지
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• 제21권3호
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• pp.107-117
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• 2000

This study examined a portfolio scale for the assessment of the writing of 295 kindergarten children. The data were analyzed by Spradley's Developmental Research Sequence(DRS), using qualitative methods. Results showed that the writing portfolio scale for 4-year-olds includes "a word or write a children's name" "picture or word with shape of letters" and "scribbling or zig-zag". The writing portfolio scale for 5- and 6-year-olds includes "invented spelling" "write according to sound" and "omitted letters" "write a good hand". The writing portfolio scale for 4-, 5-, and 6-year-olds reflects their writing experience in daily life.

• 컴퓨터교육학회논문지
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• 제17권2호
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• pp.87-95
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• 2014

e-포트폴리오(e-Portfolio)는 학생들의 학습역량 관리를 위한 훌륭한 도구로 인식된다. 본 연구에서는 저자들이 소속된 대학에서 설계하고, 시범운영 중에 있는 e-포트폴리오 시스템 'K-folio'를 소개한다. K-folio의 시스템 아키텍쳐는 대학교육을 위한 e-포트폴리오 이론적 프레임워크에 근거하여 설계하였다. 개발 방법론으로는 신속응용시스템개발방법(RAD)을 채택하였는데, 이는 기본적인 핵심기능을 구현 한 후 시범운영을 통하여 사용자 요구사항을 체계적으로 반영하면서 시스템의 완성도를 높였다. 본 연구는 다음과 같은 의의를 갖는다. 첫째, 대학 환경에 적합한 e-포트폴리오 구현모델을 제시하였다. 둘째, 본 연구에서 채택한 RAD가 e-포트폴리오 개발방법으로 매우 적합함을 발견 하였다. 셋째, e-포트폴리오구축을 위한 개발 및 운영의 기술적 시사점을 제시하였다. K-folio 시스템의 개발과 시범운영을 통하여 얻은 중요한 경험으로는 학교가 리더십을 발휘하여 사용자로 하여금 적극적으로 활용하도록 동기부여를 하고 장기적으로 자원을 투입하여 개선하는 노력이 필요함을 강조한다.

• 한국초등과학교육학회지:초등과학교육
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• 제26권4호
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• pp.372-384
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• 2007

The purposes of this study was to analyze qualitatively changes in students' experience and perceptions in relation to studying science using portfolios and any resultant effects on the portfolio itself. Five fourth-grade elementary students from one small city participated in this study. Data was collected through interviews as well as through student portfolios containing the science content matter of two units over two weeks. Observational diaries recorded by a teacher were also used to test the reliability of data collection. All interviews with students were transcribed to develop a suitable network to categorize students' responses. Students' portfolios were analyzed in order to reveal their essential characteristics in combination with their teacher's observational diaries. The results were as follows. First, student perceptions of their portfolios were categorized into three different levels; superficial, extended, and moderate perceptions. The changes in perception could also be divided into three levels; consistent-superficial, unstable, and a progressive-extended pattern. Second, the experience of students with their portfolio were investigated in terms of the following; successfully completing the elements of the portfolio, development of evidence, interaction with peers, teachers, and parents, and the standards of evaluation used for the portfolios. Third, the perceptions and experience of working on the portfolio by students had a number of direct effects on the way in which students actually created and developed their portfolios. Finally, students with positive attitudes towards their portfolios actively participated in the portfolio experience and finally understood what it meant completely. However, students with negative attitudes regarding portfolio based work, did not leave the experience with any heightened awareness of the utility or indeed, purpose of portfolio based work.

• 정보교육학회논문지
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• 제10권1호
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• pp.1-12
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• 2006

교육에 있어 평가는 교육 주체뿐만 아니라 때로는 국민적인 관심사가 된다. 최근 교육인적자원부에서 제시하는 개혁안과 사회의 요구를 반영할 때, 숫자 하나로 학생의 모든 성취 정도를 나타내는 전통적인 검사 방법은 한계가 있다. 이에 따라 구성주의를 바탕으로 교육 평가 분야에 수행평가가 대두되었으며, 포트폴리오 (Portfolio)는 수행평가 철학을 구현하는 대표적이고 효율적인 한 방법이다. 포트폴리오 평가 기법의 많은 장점과 함께 단점 역시 지적되었는데, 물리적 공간과 비용의 문제 그리고 자료접근과 검색의 비효율성 등이 그것이다. 이런 포트폴리오의 단점을 극복하면서 학생들의 ICT (Information & Communication Technology) 활용능력 향상까지 도모할 수 있는 것이 전자 포트폴리오 (Electronic Portfolio) 평가 기법이다. 본 연구의 목적은 전자 포트폴리오 평가 절차 모형을 개발하고, 각 단계별로 지침이 될 수 있는 구체적인 활동을 제안하는 것이다. 개발된 포트폴리오 평가 절차 모형은 준비, 개발, 평가, 활용의 네 단계로 이루어져 있으며 각 단계별로 교사와 학생의 활동을 구분하여 제시하였다. 본 모형은 교사, 학생, 학부모에게 포트폴리오 평가에 대한 안내를 제공하고, 교사에게는 평가과정 전반에 걸친 지침을 제공할 것으로 기대한다.

• 한국콘텐츠학회논문지
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• 제13권11호
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• pp.48-58
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• 2013

주식시장은 시간에 따라 계속 변하고 특별한 이유 없이 주가가 급등하거나 급락하는 사건들이 발생하기도 한다. 이런 이유로 주식시장은 복잡계로 인식되고 있으며 주가 변동을 예측하는 것은 어려운 일이다. 이 논문에서는 주식시장을 개별 주식들의 네트워크로 이해하고 시간에 따라 변하는 한국 주식시장 네트워크를 분석하였다. 코스피200 지수를 구성하는 137개 회사의 주식들을 대상으로 주식 사이의 상관관계를 측정한 결과 주식 간 상관관계가 매우 높을 때 주가가 급락하는 경향이 있는 것으로 나타났다. 또한, 우리는 이러한 네트워크 분석 결과를 바탕으로 주식 포트폴리오를 구성하는 방법을 제안한다. 제안 방법으로 구성된 포트폴리오의 효율성을 보이기 위해 실제 주식들을 대상으로 모의 투자 실험을 수행하였고, 마코위츠의 효율적 포트폴리오 구성 알고리즘을 이용해 구성한 포트폴리오의 수익률과 비교하였다. 실험 결과 제안 방법으로 구성된 포트폴리오는 평균적으로 약 10.6%의 수익률을 보였으며, 같은 기간 마코위츠의 효율적 포트폴리오의 수익률보다 약 3.7% 높으며, 코스피200 수익률보다 약 5.6% 정도 높게 나타났다.