• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.11
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• pp.856-863
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• 2002

Seismic qualification of the main control board(MCB) for the nuclear power plant Ulchin 5 and 6 has been performed with the guideline of ASME Section III and IEEE 344 code. As the size and weight of the MCB are too large and heavy to excite using the excitation table, finite element analysis is used in order to investigate the dynamic behaviors and structural integrity of the MCB. As the fundamental frequencies of the equipment are found to be less than 33 Hz, which is the upper frequency limit for the dynamic analysis, response spectrum analysis using ANSYS is performed in order to combine the modal stresses within the frequency limit. In order to confirm the electrical stability of the major components of the MCB. modal analysis theory has been adopted to derive the required response spectra at the component locations. As the all combined stresses obtained from the above procedures are less than the allowable stresses and no mechanical or electrical failures are found from the seismic testing, the authors can confirm the safety of the nuclear equipment MCB under the given seismic loading conditions.

• International Journal of Advanced Culture Technology
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• v.10 no.4
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• pp.569-575
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• 2022

This is a research thesis on the development of a monitoring and diagnosis device that prevents the risk of an accident through monitoring and diagnosis of a modular Main Circuit Breaker (MCB) using Vacuum Interrupter (VI) for Korean high-speed rolling stock. In this paper, a comprehensive MCB monitoring and diagnosis was performed by converging vacuum level diagnosis of interrupter, operating coil monitoring of MCB and environmental temperature/humidity monitoring of modular box. In addition, to develop an algorithm that is expected to have a similar data processing before the actual field test of the MCB monitoring and diagnosis device in 2023, the cluster analysis and factor analysis were performed using the WEKA data mining technique on the big data of Korean railroad transformer, which was previously researched by Tae Hee Evolution with KORAIL.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.4
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• pp.48-64
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• 2008

The aim of this research is to set a systemic Ecological Landscape Planning Model to cope with the destroyed landscape problems which was caused by massive development project and thoughtless development in country areas. The summary of research result are as follows. As a result of analysis on domestic and international literature, there are 60 planning index items which are nature conservation area, landscape conservation area, and build and manage wetland biotope and so on. total number of planning index is 34 after finalizing the physical index items. As a result of on-spot research, all 34 planning index after literature analysis is existing. Also, there are 38 finally-selected index which includes 4 added planning index in the process of research like natural vegetation in frequently-used spot. As a result of importance analysis on detailed planning index, most are above 5 points, which is relatively high. As a result of factor analysis on patterning for the detailed planning index, it was classified with seven elements. The first Ecological Landscape Planning model was set with integrated analysis on result of pattering for the detailed planning index and importance of detailed planning index. Based on first model, to make more systematic landscape, the analysis of MCB was conducted. As a result of MCB analysis according to planning index, it is confirmed that each planning index shows maximum. As a result of importance analysis on the 9 plans keynote, the average importance point was 4.62 for conservation area and 4.54 for enrichment area respectively. By integrating the result of importance analysis on basic aims of the first model, MCB analysis and plans, we set the second Ecological Landscape Planning model. In vertical transition, for example, 'conservation area' showed the importance point above 5.2 for all planning index except setting recreational space. Also, the analysis on parallel structure showed that relation between 'additional improvement, management, and connection' and other planning index is above 5.3 and importance on correlation with 'the part which should be protected from nature and landscape' marked 6.07 which is the highest.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.1897-1902
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• 2008

The computer system is used in many application domains and any system error in these domains may either cause critical loss or threaten environment or human life. Though examples of these domains can be found in many areas, the system, which is used in domains for carrying passengers including rolling stocks in particular, is expected to show satisfactory operation all the time. The relay control logic, which is used in rolling stocks, is complex in hardware and occupies considerably large volume. Nevertheless, it has been used for a long time, to let the system safely operate even in the occurrence of an error in the computer system. However, the relay control logic circuit is so complex that the analysis of proper circuit operation and interlocking tends to be dependent only on the designer's experiences instead of being systematically performed. Especially, the analysis following a change, addition and deletion of a previous circuit according to the requirements from a source of demand is significantly limited. In this paper, the accuracy of relay control logic is verified by the use of properties of Petri Net model. In addition, how main circuit breaker (MCB) control circuit is modeled and analyzed by the design methodology is shown.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.634-643
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• 2011

The neutral section was installed in order to prevent conflict with different phase angle source in electric railway catenary system. The speed of electric train reduced due to coasting operation by notch off when it passed the neutral section. And, the catenary wire was damaged and the accident might be happened because of the arc generation when the electric train passed the neutral section with notch off condition. The inrush current of main transformer installed tiling train is analyzed during the operation of MCB(main circuit break) passing through the neutral section. The instantaneous waveform of load current were analyzed in case of powering and regenerative braking. Inrush current waveform with run of AC railway train showed that inrush current waveform and harmonics, the inrush current generated from main transformer in train has bad effects on power quality problem. In order to reduce these inrush currents, the MCB is connected when the phase angle of voltage is 90 degree. This paper is to measure inrush current and harmonics in main transformer of high speed train in neutral section of electric railway. This measurement report is used to control minimum inrush current in algorithm and power phase angle.

• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.4
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• pp.102-115
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• 2011

The purpose of this study is to establish the evaluation model through the systematic process of selecting the indicators and to evaluate the environmental-control function on forest using GIS in Deagu for the sustainable forest planning. The 35 indicators as basic items were selected by literature review and those were squeezed into the 29 indicators through expert brainstorming. Also, the 8 indicators to evaluate environmental-control function were selected by the first survey and the 5 final indicators such as carbon sink, temperature decrease, wind formation, water circulation, air purification were determined by MCB analysis using the second survey. The evaluation model was established through the weight of each indicator by AHP analysis using the third survey. According to the result of evaluating the environmental-control function on forest, the functions around the top area of Mt. Ap, Mt. Biseul, Mt. Palgong had more than 66 scores. On the other hand, the functions around Mt. Waryong and forest of Chilgok in Buk-gu had less than 40 scores. It is necessary to improve the function through the sustainable restoration and management in case of forest that the environmental-control function was lower. Furthermore, these results will be able to be utilized as basic data in order to establish the preservation area and control development area at the urban, environmental, and forest planning.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.6
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• pp.53-66
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• 2019

The purpose of this study was to suggest indicator-based selection and improvement plans for evaluating urban regeneration projects. First, we selected the indicators by conducting expert surveys and analysis of the responses received. Additionally, using the selected indicators, we analyzed the residents' opinions in Wongogae Village, where urban regeneration projects were in progress. Based on these, we suggested a plan to improve Wongogae Village. According to the study, we classified the urban regeneration evaluation indicators into 'Physical environment', 'Social environment' and 'Economic environment' according to their characteristics. We selected urban regeneration evaluation factors through the first expert survey and MCB analysis. As a result, we selected six factors for the 'Physical environment' category: 'Traffic and pedestrian environment', 'Residential (housing) environment', 'Safety and security environment', 'Greenspace', 'Landscape improvement' and 'Public space', In the 'Social environment' category, four factors were chosen: 'Resident participation', 'Community activation', 'Role of the local government and support centers' and 'Resident education' while for the 'Economic environment' category three factors were selected: 'Local economic revitalization', 'Creating an economy-based environment', 'Job creation'. Next, we conducted a second expert survey and carried out an AHP analysis using the selected evaluation factors to derive the overall weight for each. Among the evaluation factors for urban regeneration, the 'Residential (housing) environment' has the highest weighted value of 0.108, followed by 'Local economic revitalization' and 'Resident participation'. Lastly, the analysis of the residents' opinions of Wongogae Village using the urban regeneration evaluation factors, Parking environment', 'Maintenance of old houses and living environment', 'Environment for founding town and social enterprises', 'Improve commercial and business environment', 'Maintain and activate existing business' and 'Vitalizing small regional economies such as domestic handicrafts and side-job' had high overall importance, but low satisfaction, which means that it is necessary to improve the focus. Therefore, in order to improve the urban regeneration project in villages, it is necessary to improve the parking environment by expanding public parking lots, eliminate close houses, and idle lands, or open a school playground in the village for the residents. In addition, it is essential to encourage economic activities, such as fostering village enterprises and social enterprises in connection with cooperatives and allow for the selling of the products through resident activities, such as neighboring markets.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.5
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• pp.1-11
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• 2011

Many studies which assessed the function of forest are focused on usage of citizen, but studies which focused on natural-ecological function still lack. Hence, the purpose of this study is to select and apply the evaluation indicators on natural-ecological function of forest as a base research for sustainable planing and management. First, the 35 indicators were selected by the review of the internal and external 56 literature. The 12 indicators among those were reselected as natural-ecological indicator by the first survey and 7 indicators such as green area, connectivity etc. were determined through MCB analysis by the second survey. Also, the weights of 7 indicators for the functional evaluation were computed using AHP analysis by the third survey. As aresult of AHP analysis, the naturality was showed the highest indicator by 0.189, while the NDVI was evaluated the lowest indicator by 0.063. According to the result of evaluating the natural-ecological function on forest in Daegu which was selected as suitable study area, the natural-ecological functions around the Mt. Ap and Mt. Chengryong, top of Mt. Biseul had more than 85 scores, so those were assessed as an excellent area. On the other hand, the functions around the western area of Mt. Waryong and Mt. Macheon, the Mt. Daeni of Dalseong-Gun had less than 50 scores, which means that the area had to be controled by sustainable management. Therefore, we will be able to utilize the basic data for the preservation and management at urban and environmental planning through the results of this study.

• Journal of the Korean Association of Geographic Information Studies
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• v.19 no.1
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• pp.120-140
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• 2016

The purpose of this study is to assess the green space considering functional characteristics in order to provide the base data for efficient green planning and management. The study area was the park-type green spaces in Daegu and the functions were limited in nature-ecological, environment-control, and usage functions. Thirteen indicators were selected from the literature review and MCB analysis of expert survey. The weightings of functional indicators were established through AHP analysis of expert survey. According to the results of functional assessment, Naengcheon amusement, Deagu sports, and Dalchang amusement parks had scores of more than 80 in the case of nature-ecological function. Fifteen parks such as Bokhyeon, Manchon, and Cheonnae parks had scores of more than 75 in terms of environment-control function and eleven parks such as Suseong, Dalseong, and Wolbae parks had scores of more than 80 in usage function. The findings from this study can be used as the base data and guideline for construction of new park-type green space and continuous management and remodeling of current green space.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.5
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• pp.31-48
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• 2012

The purpose of this study is to select indicators by a methodical approach and to establish a functional assessment system as a basic study for planning and constructing green space of forest. The types of green space were divided into 6 classes based on theoretical reviews of literature and the functions of green space were restricted to 'nature-ecological function', 'environment-control function' and 'usage function'. As a result of the selection of indicators, 35 indicators were initially selected by theoretical review and these indicators were reduced to 29 through brainstorming. Also, these indicators were classified into three functions such as 12 indicators (nature-ecological function), 8 indicators (environment-control function), 6 indicators (usage function) by analysis of suitability. According to the result of selection of the optimum indicators using MCB (Multiple Comparisons with the Best treatment) analysis, the optimum indicators of 7, 5, and 4 respectively by each function were selected for forest green space. The results of AHP (Analytic Hierarchy Process) for the establishment of the assessment system in forest, the weight of nature-ecological function was evaluated highest at 0.558, while the weight of environment-control and usage function were calculated at each 0.277, 0.165. 'Naturality (0.189)', 'Carbon sink (0.235)', and 'Accessibility (0.354)' among indicators showed highest by each function. The weight of indicator and assessment system may be used as a valuable guideline in case of assessing synthetically green space within urban planning.