• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.6
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• pp.1872-1881
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• 1996

LBB(Leak-Before-Break) analysis is performed for the highest stress location of each different type of mateerials in the nuclear piping line. In most cases, the highest stress occurs in the pipe and nozzle interface location. i.e. terminal end. The current finite element analysis approach utilizes the symmetry condition both for locations near the nozzle and for locationa away from the nozzle to minimize the size of the finite element model and to make analysis simple when calculating the J-integral values at the crack tip. In other words, the nozzle is not included in the finite element model. However, in reality, the symmetric condition is not applicable for the pipe-nozzle interface location. Because the pipe-nozzle interface location is asymmetric due to different stiffenss of the pipe and nozzle(both material and dimensions). The simplified analysis approach for pipe-nozzle interface locaiton is too conservative for a smaller diameter piping. In tlhis paper, various analyses are performed for the range of materials and crack sizes to evaluate the nozzle effect for a LBB anlaysis. This paper presents methodology for developing the piping evaluaiton diagram at the pipe-nozzle interface location.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.51 no.9
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• pp.467-473
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• 2002

In this paper, a fault location algorithm is suggested for line to line faults in distribution networks. Conventional fault location algorithms use the symmetrical component transformation, a very useful tool for transmission network analysis. However, its application is restricted to balanced network only. Distribution networks are, in general, operated in unbalanced manners, therefore, conventional methods cannot be applied directly, which is the reason why there are few research results on fault location in distribution networks. Especially, the line to line fault is considered as a more difficult subject. The proposed algorithm uses direct 3-phase circuit analysis, which means it can be applied not only to balanced networks but also to unbalanced networks like distribution a network. The comparisons of simulation results between one of conventional methods and the suggested method are presented to show its effectiveness and accuracy.

• The KSFM Journal of Fluid Machinery
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• v.15 no.1
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• pp.46-51
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• 2012

This study is to confirm the deformation of blade when the location of stacking is moving. Also, it desire to determine the most stable location of stacking from the analysis. In the previous study, it is Known that moving the location of stacking is not influence to the aerodynamic performance. In this study SolidWorks premium 2010 SP4 is used for structure analysis. In reference blade and other 3 model analysis, the two mesh type is used, one is standard mesh type in SolidWorks, the other is curvature-based mesh type. The result of curvature-based mesh type is more stable than one of the standard mesh type regardless of mesh size, the number of mesh. The deformation of blade tip is the smallest, when the location of stacking is identical to the center of gravity of the blade section profile. So, if possible is design, this study recommends that the location of stacking is identical to the center of gravity the blade.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.18 no.2
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• pp.77-86
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• 2022

This study investigates the effect of the diameter and thickness on crack initiation location and orientation of 90° elbows under in-plane mode displacement-controlled cyclic bending loads. Finite element (FE) analysis of cyclic failure test is conducted for elbow specimens under in-plane mode displacement-controlled cyclic bending to identify the parameters affecting crack location and orientation. Furthermore, parametric FE analysis of the pipe elbows with various pipe nominal sizes and Schedules is performed, and the crack location and orientation from the results of FE analysis are determined. It is found that the crack location and orientation in the pipe elbows are determined mianly by the radius to thickness ratio of pipe elbows (R_m/t). It is also found that the presence of internal pressure slightly increases the value of R_m/t at which the failure mode changes.

• Proceedings of the IEEK Conference
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• 2003.07a
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• pp.169-173
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• 2003

In this paper, we analyze a time-based update method in location management and calculate the optimal time-interval. We obtain the probability that an MT is j rings away from the center cell. And using these values, an exact analysis is made for the time-based location management cost. From the result, when the time-based method is applied to location update, we can get the optimal time-interval which minimizes the location management cost.

• International journal of advanced smart convergence
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• v.7 no.3
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• pp.61-65
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• 2018

A Location Register(LR) system manages each subscriber's location information, which continuously changes in mobile cellular network. For this purpose, the LR database system provides backup management facilities. The objectives of this paper are to identify the problems of the current LR system through rigorous analysis, to suggest solutions to them. I proposed efficient backup methods that takes into account the characteristics of LR database transactions. In the proposed backup method, I use two kinds of dirty flags in order to solve the performance degradation problem caused by frequent registration- location operations.

• Journal of the Korean Applied Science and Technology
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• v.36 no.2
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• pp.507-523
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• 2019

This purpose of study was to Analysis on Location and Service Factors Affecting the Management and Use of Judo Gym. This study aims at providing fundamental data and information on Judo coach by studying what effects of location and use factor on trainee satisfaction. The survey was done through 350 copies and excluding 11 copies ran an analysis on the remaining 339(96.8%) copies. After question investigating the data which is collected used IBM SPSS statistics 21 program, frequency analysis, Exploratory factor analysis, Cronbach's ${\alpha}$, correlation analysis, multiple regression. The result of this study were as follows. First, management, location, coach, trainee value, facility, communication in Judo gym location and use factors showed (+) effects on trainee satisfaction. Second, Program operation, Gym quit use, Whether or not to insure in management factor showed (+) effects on trainee satisfaction. Third, Coach credibility in coach factor showed (+) effects on trainee satisfaction. Forth, Member communication in communication factor showed (+) effects on trainee satisfaction. Fifth, Wholesome leisure, Athletic ability improving in trainee value factor showed (+) effects on trainee satisfaction. Sixth, main facility level, additional facility level in facility factor showed (+) effects on trainee satisfaction. Seventh, Visibility in location factor showed (+) effects on trainee satisfaction. And location type(station area, residential district, commercial area) of Judo gym showed (+) effect on management, trainee value, location, communication, facility.

• Journal of Korean Society of Water and Wastewater
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• v.33 no.5
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• pp.389-394
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• 2019

In order to determine the location of average concentration and distribution status of dissolved oxygen in the rectangular aeration tank of the sewage treatment plant was analyzed and the difference of dissolved oxygen concentration was remarkable at each location. Compared with the computational fluid dynamics analysis, it was found that the results were consistent with the measurement results by showing the difference of dissolved oxygen concentration between the locations. Based on the measured data, the representative location of dissolved oxygen in aeration tank was selected by using statistical analysis method and the representative location was expressed in three-dimensional coordinates(LWH : 25%, 50%, 33%) from flow direction and left wall. Also the difference between the dissolved oxygen concentration at the actual measurement location and the average concentration value of the entire aeration tank was founded, and the equations for calibrating the automatic measurement data considering the actual measurement location were calculated.

• Journal of the Korea Safety Management & Science
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• v.22 no.4
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• pp.87-100
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• 2020

Economic Development Zone(EDZ) in the province is one of the foreign policy for economic development of North Korea. North Korea has promulgated 27 Economic Development Zones(5 EDZs as central level and 22 EDZs as provincial level) to promote economic growth through the expansion of external opening policy. EDZs of the provinces play an important role in North Korea's national and regional economic growth. The purpose of this study is to select analytical criteria that can be quantified when considering the location conditions of North Korean economic development zones when domestic companies advance into North Korea according to the progress of inter-Korean economic cooperation, and derive the relative importance between the criteria. After that, based on this, we intend to quantify the evaluation of the location priority of the economic development zone. In this study, through AHP analysis results, when domestic companies enter North Korea, we derive the importance and preference of location selection factors when considering the location conditions of North Korean economic development zones. Taking into account the reality of North Korea when the Korean company entered the North economic development zone following location for evaluation. That is, logistics and transportation, industrial infrastructure, competitiveness, and management incentives. And 14 sub-factors were selected and AHP analysis was performed.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.38 no.2
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• pp.82-90
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• 2015

Location selection of distribution centers is a crucial task for logistics operators and key decision makers of an organization. This is a multi-criteria decision making (MCDM) process which includes both quantitative and qualitative criteria. In order to propose an optimized location selection model, this research suggests a hierarchical group of evaluation criteria : 5 major criteria with 15 sub-criteria. The MCDM approach presented in this research, by integrating Grey Relational Analysis (GRA) with Analytic Hierarchy Process (AHP), tends to rectify the overall quality and uncertainty of the values of evaluation criteria. An example of a location selection case in Korea is illustrated in this study to show the effectiveness of this method.