• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.4
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• pp.541-550
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• 2018

The works of preparing for missile flight test are becoming more complicated. To reduce the amount of waste time along with the complexity of the task, systematic analysis of waste factors should be performed before performing process improvement. The waste factors for missile flight test are first defined using lean-based waste factors. The improvement priorities for the defined waste factors are surveyed. For reliable analysis, AHP is used in questionnaire analysis instead of the existing method with large error. Then weighting and priority for waste factors for level 1 and Level 2 are suggested. Through AHP, we could derive reliable improvement priorities for waste factors. It is analyzed that the biggest cause of waste factors is waiting time and identified as the first item to be considered when establishing improvement plan. In addition, suggestions for improvement measures of waste factors are presented through brainstorming method. Reliable results will be an important factor in process redesign for missile flight test works.

• Journal of Korean Society of Rural Planning
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• v.10 no.4 s.25
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• pp.9-18
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• 2004

The purpose or this study is to simulate spatially the urban expansion phenomena with a cellular automata (CA) technique using GIS. A study area, Suwon city, was selected for test of model verification and application with the classified land-use maps of three data years: 1986, 1996, and 2000. The urbanized potential maps were generated with seven criteria of one geographic factor (slope of land), and six accessibility factors (time distances from city, national road, Seoul, station, and built-up boundary), considering their weighting values, which were optimized by WSM (weighted scenario method for intensity order) combined a ranking method and a AHP technique. The optimized weighting values at the urban expansion between 1986 and 1996 were applied to verify the CA model for the other expansion between 1996 and 2000. The results of model application showed that urban sprawl phenomena of the urban expansion toward rural area can be simulated spatially and temporally with several boundary conditions considering various scenarios for the criteria and parameters of the model. Ultimately, this study can contribute to reference data for land-use planning of urban fringe areas.

• Computational Structural Engineering
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• v.7 no.1
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• pp.117-124
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• 1994

Multi-level Multi-objective optimization(MLMO) for reinforced concrete framed structure is performed, and compared with the results of single-level single-objective optimization. MLMO method allows flexibility to meet the design needs such as deflection and cost of structures using weighting factors. Using Multi-level formulation, the numbers of constraints and variables are reduced at each levels, and the optimization formulation becomes simplified. The force approximation method is used to reflect the variation in design variables between the substructures, and thus coupling is maintained. And the linear approximated constraints and objective function are used to reduce the number of structural analysis in optimization process. It is shown that the developed algorithm with move limit can converge effectively to optimal solution.

• Journal of KIISE:Computing Practices and Letters
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• v.5 no.5
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• pp.611-618
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• 1999

An efficient and effective access to needed information becomes an important factor in the modern information society. Many people have developed information retrieval (IR) systems that retrieve needed information from a large amount of data at a given time. However, most freely available IR systems have been developed for English text rather than for Korean text. In this research, we have analyzed the IR system freeWAIS-sf, and localized it with the Korean morphological analyzer, namely HAM. The localized freeWAIS-sf can handle both English text and Korean text simultaneously. We have also modified the weighting scheme of freeWAIS-sf. The experimental result shows that the modified weighting scheme outperforms the original one in terms of retrieval effectiveness.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.4
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• pp.334-341
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• 2021

The fishery compensation by marine spatial planning such as routeing of ships and offshore wind farms is required objective data on whether fishing vessels are engaged in a target area. There has still been no research that calculated the number of fishing operation days scientifically. This study proposes a novel method for calculating the number of fishing operation days using the fishing trajectory data when investigating fishery compensation in marine spatial planning areas. It was calculated by multiplying the average reporting interval of trajectory data, the number of collected data, the status weighting factor, and the weighting factor for fishery compensation according to the location of each fishing vessel. In particular, the number of fishing operation days for the compensation of driftnet fishery was considered the daily average number of large vessels from the port and the fishery loss hours for avoiding collisions with them. The target area for applying the proposed method is the routeing area of ships of Jeju outer port. The yearly average fishing operation days were calculated from three years of data from 2017 to 2019. As a result of the study, the yearly average fishing operation days for the compensation of each fishing village fraternity varied from 0.0 to 39.0 days. The proposed method can be used for fishery compensation as an objective indicator in various marine spatial planning areas.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.3
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• pp.1-9
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• 2005

The interaction between hypersonic free stream and side jet flow at high altitudes is investigated by using the direct simulation Monte Carlo (DSMC) method. In order to alleviate the difficulty associated with the large density difference between the free stream and the side jet flow and to simulate the two flows simultaneously, a weighting factor technique is applied. For validation, the corner flow over a pair of plates perpendicularly attached is calculated with and without a side jet, and the results are compared with experiment. For a more realistic configuration, the flow past a blunted cone cylinder shape is solved. The leeward or windward jet is injected into the free stream and the effect on the aerodynamic force and moment is observed at various flow angles. The lambda shock effect and the wake structure are studied in terms of the surface pressure differential. A higher interaction between the free stream and the side jet flow is observed when the side jet is injected in the windward direction.

• The Journal of the Korea Contents Association
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• v.20 no.1
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• pp.217-232
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• 2020

The purpose of this study is to organize prior research related to e-commerce activation factors available to stakeholders in the online distribution industry, and to conduct FGI with e-commerce experts to calculate the importance of each factor in order based on the 3 Level Service Model of Kwon Hyeog-in (2010), the key factors derived through the preceding study and the FGI were structured and the weighting of each factor was derived using AHP methodology. In the higher factors, the private sector (0.542) > communes (0.237) > public (0.2222) appeared to be important. Sub-factories included 'search service development' (0.0970)', 'recommendation service development (0.0805)', 'consumer needs analysis (0.0534)', 'consumer consumption pattern analysis (0.0505)' and 'other platform-linked service development (0.0450)', in the order of weighting down, indicating each of the factors within the top 15 priority. The results of this study will be utilized throughout the e-commerce industry as well as e-commerce enterprises, providing an academic foundation for the rapidly growing e-commerce ecosystem.

• Journal of Korean Society for Quality Management
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• v.50 no.1
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• pp.125-138
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• 2022

Purpose: Failure Mode and Effect Analysis (FMEA) is a widely utilized technique to measure product reliability by identifying potential failure modes. Even though FMEA techniques have been studied, the form of Risk Priority Number (RPN) used to evaluate risk priority in FMEA is still questionable because of its shortcomings. In this study, we suggest common RPN(cRPN) to resolve shortcomings of the traditional RPN and show the extensibility of cRPN. Methods: We suggest cRPN which is based on Cobb-Douglas production function, and represent the various application on weighting risk factors, weighted RPN in a mathematical way, and show the possibility of statistical approach. We also conduct numerical study to examine the difference of the traditional RPN and cRPN as well as the potential application from the analysis on marginal effects of each risk factor. Results: cRPN successfully integrates previously suggested approaches especially on the relative importance of risk factors and weighting RPN. Moreover, we analyze the effect of corrective actions in terms of econometric analysis using cRPN. Since cRPN is rely on the reliable mathematical model, there would be numerous applications using cRPN such as smart factory based on A.I. techniques. Conclusion: We propose a reliable mathematical model of RPN based on Cobb-Douglas production function. Our suggested model, cRPN, resolves various shortcomings such as consideration of the relative importance, the effect of combinations among risk factors. In addition, by adopting a reliable mathematical model, quantitative approaches are expected to be applied using cRPN. We find that cRPN can be utilized to the field of industry because it is able to be applied without modifying the entire systems or the conventional actions.

• Journal of Korean Library and Information Science Society
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• v.39 no.4
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• pp.71-96
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• 2008

Recently, some universities and university libraries have implemented performance management system as a part of managerial innovation, and they have either implemented or are considering implementing BSC. Thus there are needs to develop performance indicator, which is a tool measuring performance of university libraries, based on BSC, and to assess the developed performance indicator's relative weights to analyze which indicators are essential to fulfill and improve the university library's mission. The performance indicators are also affected by the characteristics and perspectives of the people who develop them during the development process. Therefore, it is necessary to analyze the differences among the professional groups in relative weighting of the performance indicator. The purposes of this study are to derive a university library performance indicator model based on BSC, to analyze the importance of each evaluation factor of the derived performance indicator model, and to analyze the differences among the professional groups in relative weighting of the performance indicator model.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.50 no.7
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• pp.339-349
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• 2001

This paper suggests an optimal identification method for complex and nonlinear system modeling that is based on Fuzzy-Neural Networks(FNN). The proposed Hybrid Identification Algorithm is based on Yamakawa's FNN and uses the simplified inference as fuzzy inference method and Error Back Propagation Algorithm as learning rule. In this paper, the FNN modeling implements parameter identification using HCM algorithm and hybrid structure combined with two types of optimization theories for nonlinear systems. We use a HCM(Hard C-Means) clustering algorithm to find initial apexes of membership function. The parameters such as apexes of membership functions, learning rates, and momentum coefficients are adjusted using hybrid algorithm. The proposed hybrid identification algorithm is carried out using both a genetic algorithm and the improved complex method. Also, an aggregated objective function(performance index) with weighting factor is introduced to achieve a sound balance between approximation and generalization abilities of the model. According to the selection and adjustment of a weighting factor of an aggregate objective function which depends on the number of data and a certain degree of nonlinearity(distribution of I/O data), we show that it is available and effective to design an optimal FNN model structure with mutual balance and dependency between approximation and generalization abilities. To evaluate the performance of the proposed model, we use the time series data for gas furnace, the data of sewage treatment process and traffic route choice process.