• Journal of Korean Association for Spatial Structures
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• v.3 no.2 s.8
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• pp.101-107
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• 2003

There exists a structural problem for link structures in the unstable state. The primary characteristics of this problem are in the existence of rigid body displacements without strain, and in the possibility of the introduction of prestressing to change an unstable state into a stable state. When we make local linearized incremental equations in order to obtain knowledge about these unstable structures, the determinant of the coefficient matrices is zero, so that we face a numerically unstable situation. This is similar to the situation in the stability problem. To avoid such a difficult situation, in this paper a simple and straightforward method was presented by means of the generalized inverse for the numerical analysis of stability problem.

• Structural Engineering and Mechanics
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• v.21 no.3
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• pp.237-254
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• 2005

This article deals with the reconstruction of an impact force. This requires to take measurements from the impacted structures and then to deconvolve those signals from the impulse response function. More precisely, the purpose of the work described here is to analyse the method of deconvolution and the problems that it implies. Thus, it is highlighted that the associated deconvolution problem depends on the location of the measurement points: it is possible or not to reconstruct the force of impact in function of the location of this point. Then, the role of the antiresonances is linked up with this problem. The singular value decomposition is used to understand these difficulties. Numerical predictions are compared and validated with experiments.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.26 no.4
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• pp.31-41
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• 2003

This paper deals with a cell formation problem for a set of m-machines and n-processing parts. Generally, a cell formation problem is known as NP-completeness. Hence the cell formation problem with multiple objectives is more difficult than single objective problem. The paper considers multiple objectives; minimize number of intercell movements, minimize intracell workload variation and minimize intercell workload variation. We propose a multiple objective genetic algorithms(MOGA) resolving the mentioned three objectives. The MOGA procedure adopted Pareto optimal solution for selection method for next generation and the concept of Euclidean distance from the ideal and negative ideal solution for fitness test of a individual. As we consider several weights, decision maker will be reflected his consideration by adjusting high weights for important objective. A numerical example is given for a comparative analysis with the results of other research.

• Journal of the Korea Safety Management & Science
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• v.7 no.1
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• pp.87-100
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• 2005

This paper studies on the quality problem for the Reley using the 6 sigma process. The application of 6 sigma process suggested reliable and valuable statistical data for the quality of the Relay at the production line. In the measurement step in 6 sigma process, the FMEA(filure mode effect analysis) were used for the detection of problem source. The application of 6 sigma process gave the improving method for the quality of the Relay. Consequently the 6 sigma process was proved very effective for the quality problem reducing at the production line.

• Industrial Engineering and Management Systems
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• v.8 no.1
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• pp.29-36
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• 2009

We present two local-search based metaheuristics for the multi-source capacitated facility location problem. In such a problem, each customer's demand can be supplied by one or more facilities. The problem is NP-hard and the number of locations in the optimal solution is unknown. To keep the search process effective, the proposed methods adopt the following features: (1) a multi-exchange neighborhood structure, (2) a tabu list that keeps track of recently visited solutions, and (3) a multi-start to enhance the diversified search paths. The transportation simplex method is applied in an efficient manner to obtain the optimal solutions to neighbors of the current solution under the algorithm framework. Two in-and-out selection rules are also proposed in the algorithms with the purpose of finding promising solutions in a short computational time. Our computational results for some of the benchmark instances, as well as some instances generated using a method in the literature, have demonstrated the effectiveness of this approach.

• Journal of Agricultural Extension & Community Development
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• v.18 no.4
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• pp.879-902
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• 2011

This study was conducted to investigate the levels of hope and their relationship with problem behavior, academic records and procrastination among rural adolescents. The participants were 579 rural middle and high school students from three counties. The major results of the study were as follows. First, pathway and agency thinking of rural adolescents were negatively correlated with depression and anxiety, and were positively correlated with academic records and procrastination. But only agency thinking of rural adolescents were negatively correlated with delinquency among problem behaviors. Second, as a result of multivariate analysis of variance, groups of high hope of rural adolescents were lower in depression and anxiety than groups of low hope, but were higher in academic records and procrastination.

• Journal of Families and Better Life
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• v.10 no.2
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• pp.133-143
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• 1992

The Purpose of this study is to investigate the marital conflict degree, and find out how demographic variables have and effect on marital conflict. For the data , 521 Married woman living in pusan were selected. The data were analyzed with the SPSS PC+ statistical package using M.SD. Factor analysis. Pearson's correlation, one-way ANOVA, scheffe-test, multiple regression. The main results are as follows: First, items were loaded eight resource categories such as character, sexual, children, communication, husband' family, spousal digression, economic difficulties and financial affairs problem. Second, the degree of marital conflict is relatively middle. Taking a look at each conflict factor, conflict of character problem is the highest, the next is communication problem and the third is children problem. Third, among family environmental variables level of education, income, job of husband and husband's dissatisfaction with job hove influence on the marital conflict.

• Journal of the Korean Home Economics Association
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• v.46 no.1
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• pp.15-24
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• 2008

Although the relationship between physical health problems and life satisfaction is well documented, less is known about the role of coping strategies, in particular strategies for coping via religious or spiritual means. To investigate the relationships among these factors, data collected with questionnaires completed by 326 adult alcoholics at a rehabilitation agency. Significant Physical Health Problem $\times$ Religious Coping buffer interactions were found in the relationship between physical health problem and life satisfaction. Moderated regression analysis showed that religious coping reduced the impact of physical health problem on life satisfaction. Implications for practice are discussed.

• Journal of Korean Institute of Industrial Engineers
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• v.18 no.1
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• pp.169-176
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• 1992

In parts assignment problem for FMS, both the parts and the tools required to process the parts are assigned to the machine tools for a specified planning period. This is an important decision-making problem for a short-term production planning of FMS. In this paper, parts assignment problem for FMS was analyzed to determine the optimal plan which has the adaptability to production fluctuation. A mathematical model was developed for determing the parts and the tools required for the machine tools which compose FMS, and the model was analyzed to obtain optimal solution. In addition, the vality and feasibility of the computational algorithm was examined by solving a numerical example.

• Journal of the military operations research society of Korea
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• v.26 no.1
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• pp.56-69
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• 2000

A frequency assignment problem on time division duplex system is considered. Republic of Korea Army (ROKA) has been establishing an infrastructure of tactical communication (SPIDER) system for next generation and it will be a core network structure of system. VHF system is the backbone network of SPIDER, that performs transmission of data such as voice, text and images. So, it is a significant problem finding the frequency assignment with no interference under very restricted resource environment. With a given arbitrary configuration of communications network, we find a feasible solution that guarantees communication without interference between sites and relay stations. We formulate a frequency assignment problem as an Integer Programming model, which has NP-hard complexity. To find the assignment results within a reasonable time, we take a genetic algorithm approach which represents the solution structure with available frequency order, and develop a genetic operation strategies. Computational result shows that the network configuration of SPIDER can be solved efficiently within a very short time.