• Journal of Korean Institute of Industrial Engineers
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• v.15 no.1
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• pp.105-116
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• 1989

This study presents an algorithm that determines the optimal configuration of the FMSs with limited local buffers. The algorithm finds the lowest cost configuration, i.e. the number of tools, the number of pallets as well as the number of buffers to be installed in front of each machine in the system. Thus it assures a given production ratio with a minimum cost. In the algorithm, FMSs are considered as the closed queueing network with limited queue length. System performance evaluation is performed using the Block-&-Recirculation model developed by Yao and Buzacott. The algorithm is composed with three steps. The steps are namely i) determination of a lower configuration, ii) derivation of an heuristic solution, and iii) obtaining the optimal solution. The computational efforts required in the algorithm usually lies within the capability of personal computers.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.1
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• pp.66-72
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• 2007

an approach to air-vehicle design, an application of the radio-controlled model flight test techniques has been presented. The approach presented in this study is to validate the air-vehicle design configuration by analyzing the flight test results of scale model with dynamic similarities, and then to apply the analyzed results to the aerodynamic design process in early stage of the air-vehicle development. To develop practically applicable similarity laws for the subscale flying model design, the air-vehicle motions are decoupled into rotational motions for stability & control similarities and translational motions for flight performance similarities. Also, detail techniques for radio-controlled model flight test have been developed. Based on the results obtained from the radio-controlled flight test, the present approach for air-vehicle design has shown to be useful to validate the air-vehicle design configuration.

• Geophysics and Geophysical Exploration
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• v.5 no.3
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• pp.185-192
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• 2002

We made a study of 3-D migration which could precisely image data of GPR (Ground Penetrating Radar) applied to NDT (Non-Destructive Test) field for the inspection of structural safety. In this study, we obtained 3-D migrated images of important targets in structuresurvey (e.g. steel pipes, cracks) by using 3-D Kirchhoff prestack depth migration scheme developed for seismic data processing. For a concrete model consisting of steel pipe and void, the targets have been well defined with opposite amplitude according to the parameters of the targets. And migrated images using Parallel-Broadside array (XX configuration) have shown higher resolution than those using Perpendicular-Broadside array (YY configuration) when steel pipes had different sizes. Therefore, it is required to analyze the migrated image of XX configuration as well as that of general YY configuration in order to get more accurate information. As the last stage, we chose a model including two steel pipes which cross each other. The upper pipe has been resolved clearly but the lower has been imaged bigger than the model size due to the high conductivity of the upper steel.

• Journal of Digital Convergence
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• v.13 no.7
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• pp.183-196
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• 2015

In order to perform a successful outsourcing, we needs the SLA through improving the quality of IT services. In particular SLA metrics and evaluation criteria is an important factor as to substitute the IT viability of the company to promote IT Outsourcing. SLA metrics consist of technical, managerial, user perspective items, and has been managed to aim to provide reliable and continuous quality improvement of IT services. This study focuses on the HW availability metrics of SLA indicators of IT outsourcing. We propose the Infra availability criteria for the HW configuration level to meet the SLA contract and evaluation. We offer the Infra configuration standards of SLA contract, and propose criteria to determine the suitability of the target levels in IT operations audit environment. The proposed model was verified the necessity and effectiveness of the Infra configuration standards and operation audit check items through the surveys of experts and users.

• Journal of Intelligence and Information Systems
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• v.7 no.1
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• pp.149-159
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• 2001

There have been lots of researches for providing a personalized service to a customer using one-to-one marketing and collaborative filtering techniques in E-Commerce. However, there are technical difficulties for providing the recommendation of products far users, which often involve high complexity of computation. In this paper, we have presented an integrated method of classification problem solving method and constraint based configuration techniques. This method can reduce a complexity of computation by classifying a solution domain space that has a higher complexity of composition. Thereafter, we have modeled customers constraints and the components of products to configure a complete system by passing it to constraint processing module in Constraint Satisfaction Problems. Constraint-based configuration uses the constraint propagation using the constraints of buyers and the constraints among PC components to configure a proper product for a customer. We have transformed and applied vector space modeling method in the field of information retrieval to consider a customer satisfaction in addition to the CSP. Finally, we have applied our system to test data fur evaluating a customers satisfaction and performance of the proposed system.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.247-248
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• 2015

Wind turbines causes instabilities on the grid as their penetration increase. To mitigate harmful effects from wind turbines, transmission system operator(TSO) set up some requirements to obligate for wind generation operator for grid connection. So wind farm management system(WFMS) has important role to follow requirement from TSO, WFMS calculates available real power by considering wake effects, and dispatches real power order to each wind turbine in wind farm to optimize for decreasing load fatigue. To verify operation of WFMS, real-time simulator(RTS) is necessary. This paper deals with RTS configuration to verify WFMS operation. RTS includes wind farm model and power flow code. Normally, wind farm equivalent simple model makes wind turbines in wind farm to one wind turbine mode which cannot verify power flow in wind farm and WFMS operation. Thus, this paper makes wind farm model using simple wind turbine model with transfer function. Matlab is used for make power flow code and wind farm model to impose RTS and those model is certified by PSCAD/EMTDC.

• Journal of Distribution Science
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• v.10 no.11
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• pp.39-53
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• 2012

Purpose - This study identifies relationships amongst repurchase intentions, brand equity, and preference by applying VMD of fashion retail stores. The results would help coffee shop owners and coffee makers in devising an appropriate strategy for successfully managing coffee shops. Research design, data, methodology - The VMD model of a coffee shop includes harmony, trend, and attractiveness, while brand equity encompasses brand awareness, perceived quality, and brand image. In this study, the VMD factors of coffee shops, brand equity, and brand preference, are shown as independent variables, while repurchase intention is shown as the dependent variable. The study aims to ascertain the extent of the influence configuration factors of a coffee shop have on brand equity, brand preference, and repurchase intention. Regression analysis was used to verify the mediating effects of brand preference on brand equity and repurchase intention. The measurement items were already deemed as reliable and valid in the previous study, but some modifications were made for the purposes of this study. Questionnaires were distributed to 550 consumers on a national scale, and 517 consumers amongst these were finally used as a sample for analysis using the SPSS 17.0 statistical program. Results - First, amongst the VMD configuration factors of a coffee shop, trend, and attractiveness have a positive impact on brand equity (brand awareness, perceived quality, and brand image). Second, brand equity has a positive effect on brand preference. Third, brand preference has a positive effect on repurchase intention. Fourth, brand preference plays the role of a mediator in measuring the impact of brand awareness and brand image on customers' repurchase intentions. Conclusions - The theoretical implications can be summarized as follows. First, this study proposes a theoretical basis that can be adapted to the VMD configuration factors of a coffee shop by identifying the relationship between brand equity and coffee shops. This study applies the VMD factors to the coffee shops and presents a new research model by examining the relationships amongst VMD components of coffee shops: brand equity, brand preference, and repurchase intention. Second, it clearly establishes the relationship between brand equity and brand preference by identifying the mediating effects of brand preference, given that brand equity has a positive impact on repurchase intention. The practical implications are as follows. First, development of brand equity and management can be important components for coffee shops in determining that the VMD configuration factors of coffee shops have an impact on brand equity. Second, amongst the VMD configuration factors, attractiveness and trend have a positive influence on choosing coffee shops, therefore store atmosphere should be attractively designed, while the menu and interiors should complement each other and be reviewed periodically to conform to the latest trend. Third, VMD configuration factors that are confirmed are not easily changed. Fourth, large franchises and foreign companies have strengths in scale, locations, and brand. Fifth, the different ways of campaigning should be compared to those of large franchises and foreign companies in order to increase brand equity using VMD configuration factors.

• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.195-200
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• 2010

Numerical investigation was conducted to study the effects of after-body configurations and nozzle lip on the PIFS(Plume Induced Flow Separation) and eat flux to the base face. Two dimensional and axi-symmetric non-equilibrium Navier-Stoke's solver with $k-{\omega}$ SST turbulence model was used to solve the launching vehicle type configuration with propulsive jet. The experimental result of Robert J. McGhee was compared with our computational results for code validation. Three types of the after-body configurations (Straight, Boat-tail, Flare type) were simulated for this study. And the nozzle lip effect was studies using the three types of base configurations same simulation conditions. As a result of numerical investigations, higher pressure ratio condition and boat-tail after-body configuration caused severe PIFS phenomenon but the flare type after-body configuration and low pressure ratio suppressed PIFS. Flare type after-body configuration and low pressure ratio case reduced heat flux to base face. The nozzle lip dispersed the heat flux widely along the base face and the nozzle lip.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.1153-1155
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• 2017

The Launch Vehicle is made up of one system with several parts gathered together. In order to make the various parts developed in various organizations into one system, it is necessary to confirm all designs at certain point in time. Change after the design fix require controlled process to analyze the impact of the changes, to decide whether or not to make the change, and to verify that the change was implemented as intended. The configuration management procedure implemented in the above manner is also applied to the development process of KSLV-II. The CAD tool and PLM are linked with each other to perform configuration management for the 3D model, 2D drawing, and the configuration identification document.

• 유체기계공업학회:학술대회논문집
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• 1999.12a
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• pp.81-89
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• 1999

The major source of noise in the process of transporting liquids is related to the cavitation phenomenon. The control valve noise is mostly dominated by bubble dynamics under cavitating conditions. In this investigation, an orifice configuration is set-up to correlate its flow-field and acoustic signatures with those from a control valve device. The performance and noise characteristics form the orifice configuration in anechoic surroundings were measured to reveal the noise sources depending on pressure differences across the orifice configuration. The sound powers from the orifice configuration are effectively normalized using proposed scaling parameters. Flow-excited dynamic systems for which there is no strong coupling between the flow and the system response can be described using a linear source-filter model. On this assumption, the normalized sound powers can be decomposed of noise source function and a response function. To find noise sources, pressure spectra measured over a range of pressure differences are transformed into the product of two non-dimensional frequency function : $P_{ss}(He,f_{ca},x/D) = F(f_{ca})\;G(He,x/D)$. This scheme of finding noise sources is shown to be applicable to the cavitation noise from the control valve effectively Two kinds of cavitating modes based on our experimental data are found and discussed.