• Journal of Intelligence and Information Systems
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• v.26 no.1
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• pp.135-149
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• 2020

Artificial intelligences are changing world. Financial market is also not an exception. Robo-Advisor is actively being developed, making up the weakness of traditional asset allocation methods and replacing the parts that are difficult for the traditional methods. It makes automated investment decisions with artificial intelligence algorithms and is used with various asset allocation models such as mean-variance model, Black-Litterman model and risk parity model. Risk parity model is a typical risk-based asset allocation model which is focused on the volatility of assets. It avoids investment risk structurally. So it has stability in the management of large size fund and it has been widely used in financial field. XGBoost model is a parallel tree-boosting method. It is an optimized gradient boosting model designed to be highly efficient and flexible. It not only makes billions of examples in limited memory environments but is also very fast to learn compared to traditional boosting methods. It is frequently used in various fields of data analysis and has a lot of advantages. So in this study, we propose a new asset allocation model that combines risk parity model and XGBoost machine learning model. This model uses XGBoost to predict the risk of assets and applies the predictive risk to the process of covariance estimation. There are estimated errors between the estimation period and the actual investment period because the optimized asset allocation model estimates the proportion of investments based on historical data. these estimated errors adversely affect the optimized portfolio performance. This study aims to improve the stability and portfolio performance of the model by predicting the volatility of the next investment period and reducing estimated errors of optimized asset allocation model. As a result, it narrows the gap between theory and practice and proposes a more advanced asset allocation model. In this study, we used the Korean stock market price data for a total of 17 years from 2003 to 2019 for the empirical test of the suggested model. The data sets are specifically composed of energy, finance, IT, industrial, material, telecommunication, utility, consumer, health care and staple sectors. We accumulated the value of prediction using moving-window method by 1,000 in-sample and 20 out-of-sample, so we produced a total of 154 rebalancing back-testing results. We analyzed portfolio performance in terms of cumulative rate of return and got a lot of sample data because of long period results. Comparing with traditional risk parity model, this experiment recorded improvements in both cumulative yield and reduction of estimated errors. The total cumulative return is 45.748%, about 5% higher than that of risk parity model and also the estimated errors are reduced in 9 out of 10 industry sectors. The reduction of estimated errors increases stability of the model and makes it easy to apply in practical investment. The results of the experiment showed improvement of portfolio performance by reducing the estimated errors of the optimized asset allocation model. Many financial models and asset allocation models are limited in practical investment because of the most fundamental question of whether the past characteristics of assets will continue into the future in the changing financial market. However, this study not only takes advantage of traditional asset allocation models, but also supplements the limitations of traditional methods and increases stability by predicting the risks of assets with the latest algorithm. There are various studies on parametric estimation methods to reduce the estimated errors in the portfolio optimization. We also suggested a new method to reduce estimated errors in optimized asset allocation model using machine learning. So this study is meaningful in that it proposes an advanced artificial intelligence asset allocation model for the fast-developing financial markets.

• 대한공업교육학회지
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• v.34 no.2
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• pp.1-19
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• 2009

The goal of this study is to examine the status quo of industrial-educational cooperation in Technical high schools. Based upon the findings of the current conditions, this study ultimately aims to propose methods through which more active industrial-educational cooperation can be stimulated. The methods chosen for this study are reference research and surveys. The survey was conducted by imposing complete enumeration on the targeted high schools that specialize in industry related fields. The survey targets were the directions of academic affairs, the directions of practical affairs, and the directors of the educational curriculum of each school.The research results are as follows: First, the teachers recognize the necessities of having opportunities to gain specific skills in different industrial fields, having chances to get stable employment, and securing the industrial institution's competitiveness through the customized nurturing and supply of human resources as the primary goals of industrial-educational cooperation. Second, the teachers express the similar opinion that industrial-educational cooperation in their current system is inappropriate to achieve their goals. Third, the teachers claim that an educational curriculum that emphasizes industrial educational cooperation must be developed and managed. Fourth, it was found that when schools plan their educational curriculum, they often do not implement the requests from industrial institutions. Fifth, major educational program implement methods that meet the requests of the industrial institutions include field trips or the introduction of other field-based experience learning programs, the application of customized curriculums based on industrial-educational cooperation, and the invitation of industrial-educational personnel as teachers to school environments. Sixth, it was concluded that educational institutions need to proactively seek companies for cooperation; they need to support, develop, and manage school programs that are based on industrial-educational cooperation; and finally, institutions need to enthusiastically participate in the government's vocational education policies that are founded upon industrial-educational cooperation. Seventh, the enforcement of selective curriculum for the benefit of diversifying the educational program; the pursuit of balancing the specialized curriculum through shedding the national educational level provided within the regular curriculum; and the establishment of related amendments on the national level to provide effective industrial-educational cooperation have been identified as the vital factors that can develop the educational programs within high schools specializing in industry and that are closely related to industrial educational cooperation.

• Journal of the Korean Society for Library and Information Science
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• v.12
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• pp.269-327
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• 1985

This study was undertaken to meet more fully the demands for improved training of library personnel, occasioned by the rapidly changing roles and functions of libraries as they try to adapt to the vast social, economic and technological changes currently in progress in the Korean society. The specific purpose of this research is to develop a standard curriculum at the batchelor's level that will properly equip the professional personnel in Korean libraries for the changes confronting them. This study started with the premise that to establish a sound base for curriculum development, it was necessary first to determine what concepts, knowledge, and techniques are required for professional library personnel to perform it at an optimal level of efficiency. Explicitly, it was felt that for the development of useful curricula and courses at the batchelor's level, a prime source of knowledge should be functional behaviours that are necessary in the job situation. To determine specifically what these terminal performance behaviours should be so that learning experience provided could be rooted in reality, the decision was reached to use a systems approach to curriculum development, which is an attempt to break the mold of traditional concepts and to approach interaction from an open, innovative, and product-oriented perspective. This study was designed to: (1) identify what knowledge and techniques are required for professional library personnel to perform the job activities in which they are actually engaged, (2) to evaluate the educational needs of the knowledge and techniques that the professional librarian respondents indicate, and (3) to categorise the knowledge and techniques into teaching subjects to present the teaching subjects by their educational importance. The main data-gathering instrument for the study, a questionnaire containing 254 items, was sent to a randomly selected sample of library school graduates working in libraries and related institutions in Korea. Eighty-three librarians completed and returned the questionnaire. After analysing the returned questionnaire, the following conclusions have been reached: (A) To develop a rational curriculum rooted in the real situation of the Korean libraries, compulsory subjects should be properly chosen from those which were ranked highest in importance by the respondents. Characters and educational policies of, and other teaching subjects offered by, the individual educational institution to which a given library school belongs should also be taken into account in determining compulsory subjects. (B) It is traditionally assumed that education in librarianship should be more concerned with theoretical foundations on which any solution can be developed than with professional needs with particulars and techniques as they are used in existing library environments. However, the respondents gave the former a surprisingly lower rating. The traditional assumption must be reviewed. (C) It is universally accepted in developing library school curricula that compulsory subjects are concerned with the area of knowledge students generally need to learn and optional subjects are concerned with the area to be needed to only those who need it. Now that there is no such clear demarcation line provided in librarianship, it may be a realistic approach to designate subjects in the area rated high by the respondents as compulsory and to designate those in the area rated low as optional. (D) Optional subjects that were ranked considerably higher in importance by the respondents should be given more credits than others, and those ranked lower might be given less credits or offered infrequently or combined. (E) A standard list of compulsory and optional subjects with weekly teaching hours for a Korean library school is presented in the fourth chapter of this report.

• Journal of The Korean Association For Science Education
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• v.35 no.5
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• pp.841-856
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• 2015

This study sought to explore longitudinal changes in Korean fourth graders' career aspirations in science. The sample included those who had high interest, but low career aspirations in science, and the analysis focused on the concept of science identity. To achieve this study's objectives, we selected 14 participants and then conducted two in-depth interviews with them. Compared with the first interviews (4th grade), changes were observed in eight students' career aspirations in science in the second round (5th grade). While six students maintained "negative" career aspiration, six revealed "medium" and two revealed "positive" career aspiration in science. To explore the relationship between science identities and career aspirations in science, three students were selected from the sample for further study. According to the results, the aspects of science identity that students valued regarding potential careers varied individually. Depending on these aspects, each student showed different patterns in the interactions between different aspects of science identity, and between aspects of science identity and science-related career aspirations. Over time, participants' experiences and interactions with people around them produced changes in their science identity, which led to changes in their career aspirations resulting from the interactions between aspects of their science identity. Their career aspirations in science were also significantly influenced by each participant's perceptions of relationships with peers (i.e., recognition by peers and of peers) and of science-related careers. Therefore, the results suggest that students need to be provided with appropriate learning environments and guidance relating to science careers.

• Journal of The Korean Association For Science Education
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• v.36 no.3
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• pp.471-483
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• 2016

The purpose of this study is to explore how students' epistemological framing and positional framing affect the role of wonderment questions related to the activation of conceptual resources and to investigate what contexts affect students' framings during scientific model construction. Four students were selected as focus group and they participated in collaborative scientific model construction of mechanisms relating to urination. According to the results, one student whose framings were "understanding phenomena" and "facilitator" asked wonderment questions, but the others whose framings were "classroom game" and "non-respondent" were not able to activate their conceptual resources. However, they were able to activate their conceptual resources when they shared the epistemological framing of "understanding phenomena" and shifted between the positional framings of "facilitator" and "respondent." Although they were able to activate their conceptual resources, these activated resources were not able to contribute to their model when they shifted to the framings of "classroom game" and "receiver." In contrast, when students constantly shared an "understanding phenomena" framing and dynamically shifted between the framings of "facilitator" and "respondent," they were able to activate various conceptual resources and develop their group model. The students' framings were affected by the contexts. These included: when students were confronted with cognitive difficulties and were not provided proper scaffolding; when the teacher played the role of answer provider and guided the activity with correctness; when there were several possible explanatory models that students could choose from; and when the teacher played the role of thought facilitator. This study contributes to supporting teaching and learning environments for productive scientific model construction.

• Journal of Preventive Medicine and Public Health
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• v.9 no.1
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• pp.11-24
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• 1976

This study was a part of large scale of a prospective study on attitudes of professional students in medicine, nursing and teaching toward population related issues in Korea. The study was first conducted in May 1974 and then in May 1975 for the 1974 class cohot using a questionaire consisted of attitude scales and other items developed by Lee. The purpose of stuay was twohold, namely, to determine the difference in students among specializations on one hand and between the first and second years in the 1974 class cohot regarding tile subject matter. A one-way analysis of variance was used for attitude scale, and absolute and relative frequency were computed for the analysis of non-attitude scale items by employing Fishers' Ratio and Duncan's multiple range test at 5% level and chi square test at 5% level as significance tests. The hypothesis 'students in health profession are more likely to have positive attitudes toward population related issues progressively as class year advances than students in teaching profession' was tested and the following results were obtained: 1) Nursing students were more likely to display favarable attitudes toward family planning than medical or teaching students although the class cohot showed slightly negative improvement in the second year. Medical and teaching students apperaed to have slightly improved attitudes in the second year. 2) Respondents in general perceived national family planning program as a means of population control and this tendency was more true among nursing students as the class year advances than two other professional groups of students. Students in teaching profession appeared to perceive it more as a means to improve individual family welfare while health students were likely to see as to improve maternal and child health. This tendency was progressively improved as the class year advanced. 3) The majority of students regardless of their respective specializations believed that family planning program should be directed toward the improvement of individual family welfare. No progressive changes in the class cohot were observed. 4) About the plan to use contraceptives in future, no singnificant differences were observes among different specializations nor in different class years. However, the majority was confirmed to have a plan to use contracepives in future. An increasing proportion of the undecided category was observed, as class year advanced among health students. 5) Students in health profession were found to be more favorable about 'more leisure opportunities' as motive for limiting number of children whereas education students indicated the reasons as 'facilitate ambitions' and 'economic base' The progressive changes toward positive direction in both groups were observed as the class years advanced. 6) Attitudes toward induced abortions of the health students were observed to be positively related to class years while an inverse relationship was found in teaching students who showed much less favor in the subject matter than health students. This phenomenon may be due to the different exposure to learning environments unique to respective specializations. 7) Health students were found to have more favorable attitudes toward population education in general than the teaching students. The teaching students appeared to have changed more to the negative direction when they became the second year while no such development was observed in health students. The teaching students seemed to hold a very conservative position with regard to sex education in schools. 8) About the equality of sexes, the nursing group was found to be most favorable while the reverse was true in the teaching group. A change in the negative direction as the class year advanced was found in the teaching group. 9) About questions related to fertility values-the 10 percent of respondents regardless of specialization indicated that they would maintain their single status in future, however no change was observed in the second year. The desired number of children was found to be two by the majority of students in nursing, medicine and teaching in order of high proportion. No changes in a different class year were observed. The childless marriage was seen by nursing students as a problem more than other students, but a slight change in positive direction was found when the nursing students became the second year. In summing, as data supported in the above, students in health profession demonstrated more favorable attitudes toward population related issues than the teaching students and this tendency became more apparent in the second year. It was noticed that health students were more conscious about the health aspect of population and family planning program while the teaching students gave more attention to the socioeconomic aspect. The sex variable seemed to have operated in the item related to the equality of sexes. In conclusion, as data presented in the above, the hypothesis of this study was accepted except in the few items. It should be noted that the limitation of this study is the short duration of the observation in measuring the possible attitude changes. It should include curriculum analysis for the respective specializations in order to indentify the area of curriculum impact on students in future study.

• Journal of Korea Water Resources Association
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• v.56 no.6
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• pp.403-417
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• 2023

In this research, a methodology was developed for constructing an appropriate rainfall image database for estimating rainfall intensity based on CCTV video. The database was constructed in the Large-Scale Climate Environment Chamber of the Korea Conformity Laboratories, which can control variables with high irregularity and variability in real environments. 1,728 scenarios were designed under five different experimental conditions. 36 scenarios and a total of 97,200 frames were selected. Rain streaks were extracted using the k-nearest neighbor algorithm by calculating the difference between each image and the background. To prevent overfitting, data with pixel values greater than set threshold, compared to the average pixel value for each image, were selected. The area with maximum pixel variability was determined by shifting with every 10 pixels and set as a representative area (180×180) for the original image. After re-transforming to 120×120 size as an input data for convolutional neural networks model, image augmentation was progressed under unified shooting conditions. 92% of the data showed within the 10% absolute range of PBIAS. It is clear that the final results in this study have the potential to enhance the accuracy and efficacy of existing real-world CCTV systems with transfer learning.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.19 no.5
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• pp.111-124
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• 2024

Digital transformation, actively progressing in various fields, is also being applied to the education sector, bringing positive changes in many schools and education settings. However, despite continued discussions and efforts, the pace of digital transformation in Korean education has been very slow. In contrast, countries showing smooth digital transformation processes are successfully digitalizing their educational environments through continuous research, technology development, and implementation efforts. This paper aims to study international cases of successful digital transformation in the education sector and explore best applicable solutions for digital transformation in the domestic education field. The study classifies case studies into government-led and private-led initiatives based on the main drivers of digital transformation in education, considering solutions that take into account Korea's educational structure and environment. The key insights derived from the cases are as follows. First, the government-led digital transformation in domestic education lacks sustainability and consistency in its policies, overly focusing on infrastructure development. There is a need to concentrate more on the development of diverse digital transformation technologies and high-quality content. Second, countries that have successfully implemented government-led digital transformation operate excellent online integrated learning platforms that provide new technologies and digital content. It is necessary for the government to consider the development and operation of such platforms. Third, there is a need to open up the public education that is mainly led and controlled by government to the private sector further through the support of education-related venture companies and startups, while also enhancing the autonomy of individual local schools. This would facilitate technological advancement and a swift digital transformation in education through the activation of the edutech market. This research, based on the analysis of international cases, contributes to establishing the direction of digital transformation policies in Korean education and provides effective solutions for more successful implementation.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.19 no.4
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• pp.127-139
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• 2024

This study investigates the impact of edutech characteristics and both tangible and intangible educational services on the intention to re-enroll, which is directly related to the management performance of private institutes. The study aims to propose strategies to improve re-enrollment intentions and management performance based on the findings. Private education has grown continuously, complementing the limitations of public education and increasing parental dependence. This study tested the hypothesis that edutech characteristics, intangible services, and tangible services, increasingly utilized with the development of information and communication technology, would influence re-enrollment intentions. It also examined whether rapport-building behavior with parents would have a moderating effect on this relationship. The hypothesis testing results showed that among the edutech characteristics, content, intangible services such as reliability and empathy, and tangible services such as tangibility and payment accessibility positively impacted re-enrollment intentions. The hypothesis that rapport-building behavior would moderate the relationship between educational services and re-enrollment intentions was supported for empathy in intangible services and tangibility in tangible services. Based on these findings, the study proposed three strategies to improve management performance of private institutes. First, in terms of improving and managing edutech characteristics, it suggested introducing and updating edutech content and ensuring operational stability. Second, for improving and managing intangible services, it recommended managing instructor recruitment and training to enhance quality and competence, maintaining professionalism through continuous education by credible institutions, and providing level-based education for students based on the qualitative improvement of educational programs. Third, to improve and manage tangible services, it suggested setting appropriate tuition fees, offering various payment methods (online, mobile, card, bank transfer) unrestricted by time and place, and equipping interiors and facilities that enable focused learning. Additionally, considering the moderating effect of rapport-building behavior, it emphasized that improvements and management requiring costs are necessary, but making parents feel a high level of tangibility through rapport-building is also important. Furthermore, given the increasing importance of edutech based on information and communication technology, the study highlighted the need for various support measures such as government technological support and venture certification system support for institutes with an entrepreneurial spirit aiming to introduce innovative technologies such as AI technology based on large language models and AR/VR-applied metaverse environments. This study is expected to help improve the management performance of private institutes by specifically suggesting items and methods for improvement and management in the educational field.

• Journal of the Korean Society of Radiology
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• v.18 no.6
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• pp.715-724
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• 2024

We aimed to build an MR-CT interconversion model based on structure-constraints Cycle-constraints Generative Adversarial Neural Networks (scCycleGANs). We used MDCT (Somatom Definition Flash CT, SIEMENS, Germany) and 3.0T MRI (Ingenia 3.0T CX MRI, PHILIPS, Netherlands) as our hardware equipment and Python (3.12.6) and PyTorch (2.4.0) as software. The study model was scCycleGAN. We acquired 2,871 and 2,436 brain CT and MR (T2WI) images of 87 patients, respectively, and for a total of 5,307 medical images, CT and MR images taken at the same level were classified through primary evaluation, and 364, 27, and 8 pairs of images were labeled as training, validation, and test data, respectively. Then, we applied hybrid objective function to the GAN model based on the basic APS frameworks to build the model, and the evaluation of the generated model was divided into quantitative and qualitative evaluation. The qualitative evaluation was conducted on 10 radiologists with more than 20 years of experience, and the quantitative evaluation was set as PSNR, IOU, SSIM, and MAE. The results of the qualitative evaluation showed that the percentage of 'positive responses', defined as a response of 'Neutral' or better, was 63% and 96% for the Synthesis CT (sCT) and Synthesis MR (sMR) groups, respectively, while the quantitative evaluation metrics PSNR, SSIM, and MAE achieved the initial target values for both groups. Our study can be used as basic guided research in the field of medical image conversion and synthesis. And further research and complementary studies are expected to solve problems such as model lightweighting to reduce the dose burden on patients and medical costs if applied to clinical environments.