• Nuclear Engineering and Technology
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• v.40 no.7
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• pp.615-624
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• 2008

In this paper, the contribution of task types and error types involved in the human-related unplanned reactor trip events that have occurred between 1986 and 2006 in Korean nuclear power plants are analysed in order to establish a strategy for reducing the human-related unplanned reactor trips. Classification systems for the task types, error modes, and cognitive functions are developed or adopted from the currently available taxonomies, and the relevant information is extracted from the event reports or judged on the basis of an event description. According to the analyses from this study, the contributions of the task types are as follows: corrective maintenance (25.7%), planned maintenance (22.8%), planned operation (19.8%), periodic preventive maintenance (14.9%), response to a transient (9.9%), and design/manufacturing/installation (6.9%). According to the analysis of the error modes, error modes such as control failure (22.2%), wrong object (18.5%), omission (14.8%), wrong action (11.1 %), and inadequate (8.3%) take up about 75% of the total unplanned trip events. The analysis of the cognitive functions involved in the events indicated that the planning function had the highest contribution (46.7%) to the human actions leading to unplanned reactor trips. This analysis concludes that in order to significantly reduce human-induced or human-related unplanned reactor trips, an aide system (in support of maintenance personnel) for evaluating possible (negative) impacts of planned actions or erroneous actions as well as an appropriate human error prediction technique, should be developed.

• Journal of the Economic Geographical Society of Korea
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• v.16 no.4
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• pp.585-596
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• 2013

This study aims to identify the process by which local farmers are integrated into the transnational agri-food system. To that end, this study investigated the purpose and reality of the contract farming for Gold Kiwifruit between Zespri International, a transnational fruit producer based in New Zealand, and farmers in Seogwipo-si, Jeju Island. Through this contract farming, Jeju farmers were contributing to Zespri's global distribution strategy and helping the corporation meet local demand. In the process, local farmers were being integrated into the transnational agri-food system led by Zespri. In the cooperation between these two parties, the company took a limited role in providing production resources, and it consulted local producers in applying production technologies to local sites. Thanks to such practices, the company's influence on local farming was limited, and local farmers were able to function proactively in production. Therefore, the company and the farmers maintained a horizontal relationship.

• Journal of Power Electronics
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• v.14 no.5
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• pp.1047-1056
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• 2014

In most grid-connected inverters (GCI) with an LCL filter, since the design of both the LCL filter and the controller is done separately, considerable tuning efforts have to be exerted when compared to inverters using an L filter. Consequently, an integrated co-design of the filter and the controller for an LCL-type GCI is proposed in this paper. The control strategy includes only a PI current controller and a proportional grid voltage feed-forward controller. The capacitor is removed from the LCL filer and the design procedure starts from an L-type GCI with a PI current controller. After the PI controller has been settled, the capacitor is added back to the filter. Hence, it introduces a resonance frequency, which is identified based on the crossover frequencies to accommodate the preset PI controller. Using the proposed co-design method, harmonic standards are satisfied and other practical constraints are met. Furthermore, the grid voltage feed-forward control can bring an inherent damping characteristic. In such a way, the good control performance offered by the original L-type GCI and the sharp harmonic attenuation offered by the latter designed LCL filter can be well integrated. Moreover, only the grid current and grid voltage are sensed. Simulation and experimental results verify the feasibility of the proposed design methodology.

• Journal of The Korean Association For Science Education
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• v.4 no.2
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• pp.64-73
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• 1984

This study aimed at identifying the characteristics of current science curriculum in several countries in terms of its format, aims and objectives, contents and guidelines and discussed about therm. The curricula were collected from 9 countries- The United States of America(5 states), Canada(4 Provinces), England, West Germany, France, Australia, Newzealand, Japan and the republic of China. Each country had her own characteristics of science curriculum, but there also common characteristics among several countries. First, the format of science curricula in eastern countries were very different from those of western countries. The western countries had the curriculum format which included characteristics and needs of science education, philosophy and background, aims and objectives, contents, characteristics of learners, teaching and learning strategy, teaching materials, guide of experiments, evaluation methods, and other concrete informations while eastern countries had the curriculum format which included only objectives, contents and guidelines. I think that the format of science curriculum in western countries is more recommendable than that of eastern countries. Second, the aims and objectives of science curricula in eastern countries focused on scientific knowledges and concepts, while those of countries emphasized scientific methods and attitudes. Third, the contents of science curricula were very similar regardless of eastern countries or western countries. In other words, all the countries in this study emphasized life science and earth science at lower grade level and physical science at upper grade level. Especially the observation and concrete learning activities were suggested at lower grade level and logical reasoning was emphasized at upper grade level. I think that the integrated (topic-centered) science curriculum is more recommendable than our current non-integrated science curriculum in lower grade levels. Finally, the guidelines of science curriculum in eastern countries did not suggest specific information about teaching contents, experimental methods, teaching-learning activities, evaluation methods, teaching and learning meterals, while those of western countries provided more specific information which teachers could utilize very effectively.

• Journal of the Korea Society of Computer and Information
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• v.16 no.3
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• pp.65-74
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• 2011

With the rapid development of cites, urban facilities have rapidly been increasing, and the task of managing them have also become complicated more and more. In this paper, we propose and design an intelligent context awareness system that effectively operates underground facilities in u-City. The suggested system consists of three major steps. The information acquisition step receives alarm information of sensors from the integrated platform. The analysis and inference step analyzes the alarm data and related information and infers the reason why the alarm happens. The information transmission step sends the final results of context awareness to the platform and other related modules. We produced some design products such as data flow diagram, function diagram, etc. We expect that the proposed context awareness system will be embedded in the integrated platform and used for an active management strategy of urban facilities.

• Communications of Mathematical Education
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• v.24 no.4
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• pp.843-864
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• 2010

To get an undergraduate degree from mathematics education department, a student not only take a general educational technology course from education department, but also take an educational technology in mathematics education course from mathematics education department. We believe that these two courses can be integrated for preparing better mathematics teachers. For this purpose, we design an educational technology tool called JavaMAL microworld, and study strategy to integrate two courses harmoniously. This kind of approach is good for internationalization of researches on mathematics education by Korean researchers since most SSCI journal prefer an integrated approach in the educational technology related papers. In short, integrating general educational technology course and educational technology in mathematics education course is not only good to student but to professors. But just integrating two courses is not enough. Students must understand the needs and the usefulness of educational technology tool in the learning and teaching of mathematics, and must have such experience from their mathematics courses.

• Review of Culture and Economy
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• v.21 no.1
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• pp.3-20
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• 2018

This study investigates a comprehensive context between the vertical integration and concentration of Korean film market. The concentration of distribution and screening markets are result of industrial strategy to defend demand uncertainty and to pursue economies of scale. Major distributors are increasingly inclined to defend industrial risk by concentrating resources on blockbusters and bargaining power of the multiplex is getting strengthened by distribution competition to secure as many screens as possible. Vertically integrated multiplexes operate discriminatory preferential treatment to their affiliates, however, there is a difference in degree of discrimination between vertically integrated groups. Furthermore, it is difficult to exclude each other from the distribution competition in which the largest screen number has to be secured. It is difficult for multiplex only to pursue the interests of affiliates and make negative choices in screening performance. As the number of screening screens increases, the seat occupancy also increases. As a result, the polarization of the distribution and screening markets, including the screen monopoly, is a phenomenon that occurs commercial films centered markets and the unfair behavior of the vertically affiliated multiplex has a limited effect on the movie market.

• Journal of the Korea Society of Computer and Information
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• v.24 no.11
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• pp.99-107
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• 2019

The "Risk management" and "Security monitoring" activities for cyber security are deeply correlated in that they prepare for future security threats and minimize security incidents. In addition, it is effective to apply a pattern model that visually demonstrates to an administrator the threat to that information asset in both the risk management and the security system areas. Validated pattern models have long-standing "control chart" models in the traditional quality control sector, but lack the use of information systems in cyber risk management and security systems. In this paper, a cyber Security Risk Monitoring (SRM) system that integrates risk management and a security system was designed. The SRM presents a strategy for applying 'security control' using the pattern of 'control charts'. The security measures were integrated with the existing set of standardized security measures, ISMS, NIST SP 800-53 and CC. Using this information, we analyzed the warning trends of the cyber crisis in Korea for four years from 2014 to 2018 and this enables us to establish more flexible security measures in the future.

• Journal of Contemporary Eastern Asia
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• v.18 no.1
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• pp.7-29
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• 2019

This study describes an approach for comparative bibliometric analysis of scientific publications related to (i) individual or several departments comprising a university, and (ii) broader integrated subject areas using multiple disciplinary schemes. It uses a custom dataset of scientific publications (ca. 15,000 articles and reviews, published during 2009-2013, and recorded in the Web of Science Core Collections) with author affiliations to the research departments, dedicated to science, technology, engineering, mathematics, and medicine (STEMM), of a comprehensive university. The dataset was subjected, at first, to the department level and discipline level analyses using the newly available KAKEN-L3 classification (based on MEXT/JSPS Grants-in-Aid system), hierarchical clustering, correspondence analysis to decipher the major departmental and disciplinary clusters, and visualization of the department-discipline relationships using two-dimensional stacked bar diagrams. The next step involved the creation of subsets covering integrated subject areas and a comparative analysis of departmental contributions to a specific area (medical, health and life science) using several disciplinary schemes: Essential Science Indicators (ESI) 22 research fields, SCOPUS 27 subject areas, OECD Frascati 38 subordinate research fields, and KAKEN-L3 66 subject categories. To illustrate the effective use of the science mapping techniques, the same subset for medical, health and life science area was subjected to network analyses for co-occurrences of keywords, bibliographic coupling of the publication sources, and co-citation of sources in the reference lists. The science mapping approach demonstrates the ways to extract information on the prolific research themes, the most frequently used journals for publishing research findings, and the knowledge base underlying the research activities covered by the publications concerned.

• Quality Improvement in Health Care
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• v.24 no.2
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• pp.2-14
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• 2018

Purpose: The objective of this study was to report the incidence of falls in hospitals and analyze the risk factors for falls. Methods: This study used data on 1,216 patients who experienced falls from 2015 to 2017 during their hospitalization. The data was collected from the falls incident reports and patient' electronic medical record of hospital. Data were analyzed with descriptive statistics using Chi-square test, Fisher's exact test and multiple Poisson regression analysis with the SAS 9.4 Results: The incidence of falls was 1.38 per 1,000 patients days (2015), 1.81 per 1,000patients days (2016) and 1.99 per 1,000patients days (2017). The incidence of injury caused by falls (level III~V) was 0.05 per 1,000patients days (2015), 0.04 per 1,000patients days (2016) and 0.06 per 1,000patients days (2017). The largest number of falls occurred during night shift (42.5%), specifically in the patients' room (70.8%), and medical unit (66.0%). Average age of fallers was 69.1 years and 61.7% of them were older than 71 years. CCI and the patient's department have statistically significant differences in injury or injury levels from falls, but the integrated nursing care services had no significant difference in injury or injury levels from falls. Conclusion: The result of this study can be used as a reference for establishing a fall prevention strategy for hospitalized patients by presenting index values such as the fall rate.