• 한국학교ㆍ지역보건교육학회지
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• 제11권1호
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• pp.67-78
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• 2010

Background & Objectives: Current trend is that funding agencies require investigators to share their data with others. However, there is limited guidance how to access and utilize the shared data. We sought to determine what common data sharing practices in U.S.A. are, what data-related to adolescent health are freely available, and how we deal with the large dataset adopting the complex study design. Methods: The study included only research data-related to adolescent health which was collected in USA and unlimitedly accessible through the internet. Only the raw data, not aggregated, was considered for the study. Major keywords for web search were "adolescent", "children", "health", and "school". Results: Current approaches for public health data sharing lacked of common standards and varied largely due to the data's complex nature, large size, local expertise and internal procedures. Some common data sharing practices are unlimited access, formal screened access, restricted access, and informal exclusive access. The Inter-University Consortium for Political and Social Research and the Center for Disease Control and Prevention were the best data depository. "Data on the net" was search engine for the website providing data freely available. Six datasets related to adolescent health freely available were identified. The importance and methods of incorporating complex research design into analysis was discussed. Conclusion: There have been various attempts to standardize process for open access and open data using the information technology concept. However, it may not be easy for researchers to adapt themselves to this high technology. Therefore, guidance provided by this study may help researchers enhance the accessibility to and the utilization of the open source data.

• Nuclear Engineering and Technology
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• 제52권8호
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• pp.1626-1637
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• 2020

This work covers an important point of the benchmark released by the expert group on Uncertainty Analysis in Modeling of Light Water Reactors. This ambitious benchmark aims to determine the uncertainty in light water reactors systems and processes in all stages of calculation, with emphasis on multi-physics (coupled) and multi-scale simulations. The Gesellschaft für Anlagen und Reaktorsicherheit methodology is used to propagate the thermal-hydraulic uncertainty of macroscopic parameters through TRACE5.0p3/PARCSv3.0 coupled code. The main innovative points achieved in this work are i) a new thermal-hydraulic model is developed with a highly-accurate 3D core discretization plus an iterative process is presented to adjust the 3D bypass flow, ii) a control rod insertion occurrence -which data is obtained from a real PWR test- is used as a transient simulation, iii) two approaches are used for the propagation process: maximum response where the uncertainty and sensitivity analysis is performed for the maximum absolute response and index dependent where the uncertainty and sensitivity analysis is performed at each time step, and iv) RESTING MATLAB code is developed to automate the model generation process and, then, propagate the thermal-hydraulic uncertainty. The input uncertainty information is found in related literature or, if not found, defined based on expert judgment. This paper, first, presents the Gesellschaft für Anlagen und Reaktorsicherheit methodology to propagate the uncertainty in thermal-hydraulic macroscopic parameters and, then, shows the results when the methodology is applied to a PWR reactor.

• Journal of Ginseng Research
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• 제11권1호
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• pp.10-16
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• 1987

인삼제품의 품질관리와 효능연구의 시료사용에 참고자료로 활용하기 위하여 인삼근의 부위별, 연근별 사포닌 함량 및 분포를 조사하였다. 한국인삼 6년근의 부위별 조성은 뇌두(rhizome) 4.1%, 동체(main root) 47.7%, 지근(lateral)의 비는 대략 1:1이었으나 지근부는 2:1로 피층이 많았다. 사포닌분포는 동체와 세근부가 29% 정도로 거의 같고, 지근부 34.6%로 가장 많았고, 뇌두는 7% 수준으로 가장 적었다. 그러나 단위 중량당 함량에서는 세근>퇴두>지근>동체의 순으로 뇌두가 높은 반면 동체는 가장 낮았다. 연근별 사포닌 변화는 2년근 4.89%, 6년근 7.98%로서 본포이식후 4년간 약 3% 증가에 그쳤으나 뿌리의 비대성장을 고려할 때 계속적으로 합성축적 되었으며 연간 증가율은 5년근이 43.8%로 가장 왕성한 성장기임을 나타내고 4년근 19.8%, 6년근 21.1%로 비슷했다. 따라서 5년에 뿌리의 생장과 사포닌 합성축적이 최고 수준에 도달했다가 6년째 부터 쇠퇴기로 됨을 알았다. 개별 사포닌의 함량변화는 전반적으로 증가하는 경향이나 PT계 사포닌보다는 PD계 사포닌의 증가가 보다 큰 경향이었다.

• Journal of Communications and Networks
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• 제6권3호
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• pp.216-225
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• 2004

In a cellular network, if there are too many data users in a cell, data may suffer long delay, and system's quality-of-service (QoS) will degrade. Some traditional schemes such as dynamic channel-allocation scheme (DCA) will assign more channels to hot (or overloaded) cells through a central control system (CC) and the throughput increase will be upper bounded by the number of new channels assigned to the cell. In mobile-assisted data forwarding (MADF), we add an ad-hoc overlay to the fixed cellular infrastructure and special channels-called forwarding channels- are used to connect mobile units in a hot cell and its surrounding cold cells without going through the hot cell's base station. Thus, mobile units in a hot cell can forward data to other cold cells to achieve load balancing. Most of the forwarding-channel management work in MADF is done by mobile units themselves in order to relieve the load from the CC. The traffic increase in a certain cell will not be upper bounded by the number of forwarding channels. It can be more if the users in hot cell are significantly far away from one another and these users can use the same forwarding channels to forward data to different cold neighboring cells without interference. We find that, in a system using MADF, under a certain delay requirement, the throughput in a certain cell or for the whole net-work can be greatly improved.

• 한국측량학회지
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• 제13권2호
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• pp.141-151
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• 1995

일반적으로 GIS의 기초자료로 인공위성 화상데이타를 이용하여 수치표고모델(DTM)을 생성하는 것이 기존 지형도 및 항공사진을 이용할 경우보다 자료획득의 시의성과 경제성에서 유리하다. 본 연구에서는 단사진 표정 원리를 응용하여 외부표정요소를 결정하고 Coarse to Fine법에 기초한 Image Matching 프로그램 및 DTM생성 프로그램을 개발하였다. 생성된 DTM을 이용하여 정사투영화상, 조감도, 등고선도 등을 제작하고 지형분석 및 수계분석을 실시하였다. 생성된 DTM의 정확도 분석 및 다양한 처리를 통하여 위성 데이타를 이용하여 생성된 DTM을 수치지도, 시설물관리, 국토정보체계 등과 같은 GIS의 응용분야에 적용 가능함을 제시하였다. 본 연구결과는 추후 보다 더 일반적인 환경 및 우리 국토 전역에 적용될 수 있도록 연구, 검토되어야 한다.

• Nuclear Engineering and Technology
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• 제40권7호
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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.

• Nuclear Engineering and Technology
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• 제53권7호
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• pp.2104-2125
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• 2021

This paper presents the verification and validation (V&V) of a calculation module for isotope inventory prediction to control the back-end cycle of spent nuclear fuel (SNF). The calculation method presented herein was implemented in a two-step code system of a lattice code STREAM and a nodal diffusion code RAST-K. STREAM generates a cross section and provides the number density information using branch/history depletion branch calculations, whereas RAST-K supplies the power history and three history indices (boron concentration, moderator temperature, and fuel temperature). As its primary feature, this method can directly consider three-dimensional core simulation conditions using history indices of the operating conditions. Therefore, this method reduces the computation time by avoiding a recalculation of the fuel depletion. The module for isotope inventory calculates the number densities using the Lagrange interpolation method and power history correction factors, which are applied to correct the effects of the decay and fission products generated at different power levels. To assess the reliability of the developed code system for back-end cycle analysis, validation study was performed with 58 measured samples of pressurized water reactor (PWR) SNF, and code-to-code comparison was conducted with STREAM-SNF, HELIOS-1.6 and SCALE 5.1. The V&V results presented that the developed code system can provide reasonable results with comparable confidence intervals. As a result, this paper successfully demonstrates that the isotope inventory prediction code system can be used for spent nuclear fuel analysis.

• 정보화정책
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• 제26권2호
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• pp.3-23
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• 2019

이 연구에서는 Mobility 신산업 관련 동향 및 전망을 정리하고 쟁점들을 제시하였다. 규제 및 갈등 관련 이슈, 기존 사업자와의 이해충돌, 플랫폼 노동 문제, 지역 간 갈등이 대표적인 쟁점으로 정리된다. 이어서 관련 신산업에 대한 정부 규제 현황 및 전망을 관련 연구들로 제시하였다. 마지막으로 갈등연구를 소개하면서 정부의 역할에 대한 정책 방향성을 제언하였다. 제언으로는 생태계 활성화를 위해 정부의 갈등 중재 노력과 복지 안전망의 연계, 그리고 신사업자의 사회적 가치 지향을 논의하였다. 결국 다양한 부처와 이해관계자가 규제 개선 과정에 참여할 수 있는 제도 환경을 조성하고, 이러한 환경에서 중심을 잡아주는 역할을 수행할 수 있는 컨트롤타워를 만드는 것이 추진과정에서 선결되어야 할 것이다.

• Nuclear Engineering and Technology
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• 제54권3호
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• pp.1115-1125
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• 2022

Nuclear power plant (NPP) is currently considered as one of the most reliable power sources. However, 182 of them are considered decommissioned and inactive including the one in Bataan, Philippines. The aim of this study was to investigate the acceptance of the reopening of Bataan Nuclear Power Plant (BNPP) by integrating the Theory of Planned Behavior and Protection Motivation Theory. A total of 815 Filipinos answered an online questionnaire which consisted of 37 questions. The Structural Equation Modeling (SEM) indicated that knowledge towards nuclear power plants was the key factor in determining people's acceptance towards NPP reopening. In addition, knowing the benefits would lead to positive perceived behavioral control (PBC) and attitude towards intention. Results showed that PBC and attitude are mediators towards the acceptance of people regarding the reopening of BNPP. If an individual's knowledge gravitates towards the perceived risk, then this can lead to the negative acceptance of the NPP reopening. On the other hand, if an individual's knowledge gravitates towards the perceived benefits, then this will lead to positive acceptance. This study is the first study that explored the acceptance of the reopening BNPP. Finally, the study's model construct would also be very beneficial for researchers, government, and even private sectors worldwide.

• Nuclear Engineering and Technology
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• 제53권4호
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• pp.1189-1198
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• 2021

When performing remote tasks using robots in nuclear power plants, a 3D shape measurement system is advantageous in improving the efficiency of remote operations by easily identifying the current state of the target object for example, size, shape, and distance information. Nuclear power plants have high-radiation and underwater environments therefore the electronic parts that comprise 3D shape measurement systems are prone to degradation and thus cannot be used for a long period of time. Also, given the refraction caused by a medium change in the underwater environment, optical design constraints and calibration methods for them are required. The present study proposed a method for developing an underwater 3D shape measurement system with improved radiation tolerance, which is composed of commercial electric parts and a stereo camera while being capable of easily and readily correcting underwater refraction. In an effort to improve its radiation tolerance, the number of parts that are exposed to a radiation environment was minimized to include only necessary components, such as a line beam laser, a motor to rotate the line beam laser, and a stereo camera. Given that a signal processing circuit and control circuit of the camera is susceptible to radiation, an image sensor and lens of the camera were separated from its main body to improve radiation tolerance. The prototype developed in the present study was made of commercial electric parts, and thus it was possible to improve the overall radiation tolerance at a relatively low cost. Also, it was easy to manufacture because there are few constraints for optical design.