• Nuclear Engineering and Technology
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• v.44 no.4
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• pp.369-378
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• 2012

A load-following operation in APR+ nuclear plants is necessary to reduce the need to adjust the boric acid concentration and to efficiently control the control rods for flexible operation. In particular, a disproportion in the axial flux distribution, which is normally caused by a load-following operation in a reactor core, causes xenon oscillation because the absorption cross-section of xenon is extremely large and its effects in a reactor are delayed by the iodine precursor. A model predictive control (MPC) method was used to design an automatic load-following controller for the integrated thermal power level and axial shape index (ASI) control for APR+ nuclear plants. Some tracking controllers employ the current tracking command only. On the other hand, the MPC can achieve better tracking performance because it considers future commands in addition to the current tracking command. The basic concept of the MPC is to solve an optimization problem for generating finite future control inputs at the current time and to implement as the current control input only the first control input among the solutions of the finite time steps. At the next time step, the procedure to solve the optimization problem is then repeated. The support vector regression (SVR) model that is used widely for function approximation problems is used to predict the future outputs based on previous inputs and outputs. In addition, a genetic algorithm is employed to minimize the objective function of a MPC control algorithm with multiple constraints. The power level and ASI are controlled by regulating the control banks and part-strength control banks together with an automatic adjustment of the boric acid concentration. The 3-dimensional MASTER code, which models APR+ nuclear plants, is interfaced to the proposed controller to confirm the performance of the controlling reactor power level and ASI. Numerical simulations showed that the proposed controller exhibits very fast tracking responses.

• Journal of the Korean Chemical Society
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• v.61 no.1
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• pp.34-44
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• 2017

The purpose of this study was to analyze the conception type change and to investigate the effect of understanding on concepts in electrochemistry after general chemistry lessons. The significant differences in concept understanding of electrochemistry were shown in both groups. Statistically significant gains in both groups were as shown in distinguishing the chemical cell, in identifying the anode and cathode, and in understanding current formation and flow, while, significant achievements in understanding the role of the salt bridge, and the need for a standard half-cell were not found. Taking elective chemistry II in high school had an effect on understanding related concepts of electrochemistry in general chemistry lessons. It was shown that many freshmen had difficulties in understanding exact related concepts in several kinds after general chemistry lessons. In order to solve these problems, it is necessary to teach contents of the basic concepts in electrochemistry exactly and to hold supplementary lessons.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.3
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• pp.331-340
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• 2010

The basic theory and application of new adaptive finite element algorithm have been proposed in this study including the adaptive hp-refinement strategy, and the effective method for constructing hp-approximation. The hp-adaptive finite element concept needs the integrals of Legendre shape function, nonuniform p-distribution, and suitable constraint of continuity in conjunction with irregular node connection. The continuity of hp-adaptive mesh is an important problem at the common boundary of element interface. To solve this problem, the constraint of continuity has been enforced at the common boundary using the connectivity mapping matrix. The effective method for constructing of the proposed algorithm has been developed by using hierarchical nature of the integrals of Legendre shape function. To verify the proposed algorithm, the problem of simple cantilever beam has been solved by the conventional h-refinement and p-refinement as well as the proposed hp-refinement. The result obtained by hp-refinement approach shows more rapid convergence rate than those by h-refinement and p-refinement schemes. It it noted that the proposed algorithm may be implemented efficiently in practice.

• Journal of Cadastre & Land InformatiX
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• v.45 no.1
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• pp.1-15
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• 2015

Korea's Spatial Information Policy has been institutionalized based by "National Spatial Data Infrastructure Act", "Act on Land Survey, Waterway Survey and Cadastral Records", "Spatial Data Industry Promotion Act". In year 2015, These acts were modified with new names and contents. It is critical that the definition of spatial information ought to be generalized. In addition, it is of paramount importance to review factors those contribute to the systematic development on coherent relation between Spatial Information Act and other acts. Examples of improvement area may include: Categorization of Spatial Information Concept, Systematization of Spatial Data Related Legislation, and Enhancement of Organization Specializing in Spatial Information. Furthermore, Legislation & Policy case of Germany, France and the United States were used as a basis for improvement.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.808-812
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• 2008

Recently, the buildings have been likely to shape Super Tall trend. Therefore, the exterior parts of the buildings come to be changed. Instead of early heavy wall structure, it is changed to light wall concept of curtain wall system. However, the curtain wall system causes lots of loads due to the external surrounding factors of building. In particular, due to the densely built-up condition in Korea, the generation of dew condensation is getting severer Since there has been no standardized process that reviews this generation of dew condensation, it is very urgent for us to prepare the reviewing process for the dew condensation for construction business managers. The purpose of this study is to assess dew condensation function of the curtain wall and provide the basic data for the provision of the future dew condensation review process by comparing and analyzing the range of generation of dew condensation as well as temperature distribution according to the change of relative humidity at the identical temperature by selecting the Unitized system and Stick system which are the representative types of curtain wall system.

• Asian Oncology Nursing
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• v.10 no.2
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• pp.146-155
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• 2010

Purpose: This study was conducted in order to analyze themes, concepts, research methods and results of previous domestic research on the nursing of hematologic patients conducted through the last 10 yr, to find trends in the research, and to provide basic materials for setting the direction of future research on the nursing of hematologic patients. Methods: This study analyzed a total of 72 nursing theses related to hematology sampled from domestic theses for a master's or doctoral degree and papers published in six nursing journals registered in Korea Research Foundation from January 2000 to July 2009. Results: Of the 72 theses, 51 were for a master's degree, 7 for a doctoral degree, and 14 not for an academic degree. The concept covered most frequently in correlation research was 'quality of life' and concepts found in comparative research were stress and quality of life. In experimental research, the most common nursing intervention was oral care. The scale used most frequently was Spielberger's Anxiety Scale. Conclusion: It is necessary to expand experimental research applying nursing interventions, and to use objective physiological indexes for more effective assessment in experimental research. Furthermore, interdisciplinary research is required for enhancing the quality of clinical nursing research.

• Journal of Satellite, Information and Communications
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• v.5 no.2
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• pp.50-56
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• 2010

Most mission trajectory design technologies for space exploration have been utilized the Patched Conic Approximation which is based on Hohmann transfer in two-body problem. The Hohmann transfer trajectory is basically an elliptic trajectory, and Patched Conic Approximation consists of Hohmann transfer trajectories in which each trajectory are patched to the next one. This technology is the most efficient method when considering only one major planet at each patch trajectory design. The disadvantages of the conventional Patched Conic Approach are more fuel (or mass) needed and only conic trajectories are designed. Recent space exploration missions need to satisfy more various scientific or engineering goals, and mission utilizing smaller satellites are needed for cost reduction. The geometrical characteristics of three-body dynamics could change the paradigm of the conventional solar system. In this theoretical concept, one can design a trajectory connecting around the solar system with comparably very small energy. In this paper, the basic three-body dynamics are introduced and a spacecraft mission trajectory is designed utilizing the three-body dynamics.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.1041-1047
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• 2020

The intention of this paper is to give a better understanding about the implementation of sustainable manufacturing practice in the textile companies in Indonesia as one of the promising sectors in the manufacturing industry. The data was collected by taking a case study approach in one of the leading textile companies in Indonesia. Questionnaire and interview techniques were used to gather in-depth information about the implementation of a sustainable concept in the company. The result reveals that the extent of the implementation of Sustainable Manufacturing Practices (SMP) in the companies are at a level of moderate to high. From the three dimensions measured which are environment, economy, and social dimensions, the evaluation result shows good performance in terms of the implementation of sustainable concepts, like low level of gas emission, high percentage of renewable energy usage, cost reduction rate, high quality of life, etc. From this result, the authors then develop a sustainable manufacturing model in the wider coverage to be implemented not only in the textile industry but is expected to be implemented in manufacturing sectors as well. This model consists of at least seven basic archetypes which are divided into three dominant areas: technological innovation, economical, and social areas which aim to bring better performance in the manufacturing industry of Indonesia.

• Journal of KIISE:Software and Applications
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• v.28 no.12
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• pp.885-895
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• 2001

Existing system analysis models suggest various ideas to present entity relations and event flows for consistency between analysis and design paradigms. However, they are preferred to derive and arrange related entities on system flow than to identify entities. To identify entities systematically is a basic and important work of software development, and identified entities can be major assets of business system. In case of business systems the business rules or the computed or derived information like attendance lists of lecture system can be the most important system assets. The management information or meta data are also. In this paper, we suggest a business system analysis models to derive and present entities. System is identified entities, interfaces and event or behaviors through this model then entities are extended to independent entities, dependent entities, which are dependent to independent entities, constraint shows the physical and administrative notices. Various entity identification can reduce the incompleteness of entity analysis.

• Journal of KIISE:Software and Applications
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• v.26 no.12
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• pp.1468-1481
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• 1999

didates.본 논문은 절차 중심 소프트웨어를 객체 지향 소프트웨어로 재/역공학하기 위한 다단계 절차중 첫 절차인 객체 추출 절차에 대하여 기술한다. 사용한 객체 추출 방법은 전처리, 기본 분할 및 결합, 정제 결합, 결정 및 통합의 다섯 단계로 이루어진다 : 1) 전처리 과정에서는 객체 추출을 위한 FTV(Function, Type, Variable) 그래프를 생성/분할 및 클러스터링하고, 2) 기본 분할 및 결합 단계에서는 다중 객체 추출을 위한 그래프를 생성하고 생성된 그래프의 정적 객체를 추출하며, 3) 정제 결합 단계에서는 동적 객체를 추출하며, 4) 결정 단계에서는 영역 모델링과 다중 객체 후보군과의 유사도를 측정하여 영역 전문가가 하나의 최적합 후보를 선택할 수 있는 측정 결과를 제시하며, 5) 통합 단계에서는 전처리 과정에서 분리된 그래프가 여러 개 존재할 경우 각각의 처리된 그래프를 통합한다. 본 논문에서는 클러스터링 순서가 고정된 결정론적 방법을 사용하였으며, 가능한 경우의 수에 따른 다중 객체 후보, 객관적이고 의미가 있는 객체 추출 방법으로의 정제와 결정, 영역 모델링을 통한 의미적 관점에 기초한 방법 등을 사용한다. 이러한 방법을 사용함으로써 전문가는 객체 추출 단계에서 좀더 다양하고 객관적인 선택을 할 수 있다.Abstract This paper presents an object extraction process, which is the first phase of a methodology to transform procedural software to object-oriented software. The process consists of five steps: the preliminary, basic clustering & inclusion, refinement, decision and integration. In the preliminary step, FTV(Function, Type, Variable) graph for object extraction is created, divided and clustered. In the clustering & inclusion step, multiple graphs for static object candidate groups are generated. In the refinement step, each graph is refined to determine dynamic object candidate groups. In the decision step, the best candidate group is determined based on the highest similarity to class group modeled from domain engineering. In the final step, the best group is integrated with the domain model. The paper presents a new clustering method based on static clustering steps, possible object candidate grouping cases based on abstraction concept, a new refinement algorithm, a similarity algorithm for multiple n object and m classes, etc. This process provides reengineering experts an comprehensive and integrated environment to select the best or optimal object candidates.