• Journal of Korean Society for Quality Management
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• v.8 no.2
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• pp.15-22
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• 1980

This paper deals with the problem of determining a minimum cost sampling inspection plan for a single destructive testing by attribute. The cost for inspection lot is constructed by following three cost factors: (1) cost of inspection, (2) cost of accepted defective, (3) cost of rejected lot Using Hald's Bayesian approach in a single non-destructive testing, procedure's for finding the minimum cost single destructive sampling inspection plan by attribute are given. Assuming the uniform distribution as a prior-distribution and using numerical analysis by computer, a minimum cost single destructive sampling inspection plan by attribute for several lot sizes, unit cost, destructive testing cost, and salvage cost is given.

• Journal of Families and Better Life
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• v.28 no.6
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• pp.195-205
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• 2010

households using the 2007 Korean Retirement and Income Study. Elderly households were classified into three groups based on the comparisons among the costs of living and then the factors influencing the probability of belonging to each group were investigated using multiple logistic regression models. The major findings are as follows. Firstly, the subjective adequate cost of living was the highest and the subjective minimum cost of living was the lowest. The actual cost of living was in between. Secondly, 42.6% of elderly households belonged to Group1(whose actual cost of living was less than the subjective minimum cost of living), 30.0% was classified into Group2(whose actual cost of living was greater than the subjective minimum cost of living but less than the subjective adequate cost of living) and the actual cost of living of the remaining 27.4% was greater than the subjective adequate cost of living(Group3). Thirdly, income was the strongest factor influencing the probability of belonging to each group, but the influencing factors were different for the logistic models for Group1 and Group3 based on Group2.

• Journal of the military operations research society of Korea
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• v.25 no.2
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• pp.84-96
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• 1999

The purpose of this paper is to find the most vital arc in the minimum cost flow problem. The most vital arc is the arc whose removal results in the greatest influence in the costs or the amount of demands in a given minimum cost flow network. This problem can be well applied to the conflict situations such as military logistics network or communications network. In this situation, network user wants to know which arcs are the most vital to him so that he can reinforce these arcs against attack, while interdictor wants to destroy these arcs which increase the distance of the shortest path most through the network. When one of arcs is removed from the network of the minimum cost flow problem, two kinds of situations can be occurred ; breaking feasibility and increasing cost. In case of breaking feasibility, the rank of arcs are determined using the amount of modified flow in a related network which is made of modifying the optimal alternative of the minimum cost flow problem. The rank of arcs with the increased costs are determined by using a method which finds the directed cycle with the minimum cost in a related network.

• Journal of the Society of Naval Architects of Korea
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• v.48 no.2
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• pp.178-182
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• 2011

Generally in order to reduce the steel weight of stiffened plate, stiffener spaces tend to be narrow and the plate gets thin. However, it will involve more fabrication cost because it can lead to the increase of welding length and the number of structural members. In the yard, the design which is able to reduce the total fabrication cost is needed, although it requires more steel weight. The purpose of this study is to find optimum stiffener spaces to minimize the fabrication cost for the cargo tank of LPG Carriers. Global optimization methods such as ES(Evolution Strategy) and GA(Genetic Algorithm) are introduced to find a global optimum solution and the sum of steel material cost and labor cost is selected as main objective function. Convergence degree of both methods in according to the size of searching population is examined and an efficient size is investigated. In order to verify the necessity of the optimum design based on the cost, minimum weight design and minimum cost design are carried out.

• Proceedings of the IEEK Conference
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• 2000.06b
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• pp.213-216
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• 2000

Minimum-cost linear network flow problems could be transformed with equal to assignment problems. Traditional method to solve the linear network flow problems are improved source-cost by transform the simple cycle flow. Auction algorithm could be applied to same element using the initial target price and dispersion calculation. Also, each elements are obtained by $\varepsilon$-relaxation methods. In this paper we proposed; 1)minimum-cost flow problem, 2)minimum-cost flow problem by the mathematical equivalent and 3) extraction $\varepsilon$-relaxation & expand transfer problem with minimum-cost flow. It can be applicant to PCB design by above mentioned.

• Journal of The Korean Society of Agricultural Engineers
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• v.49 no.6
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• pp.93-101
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• 2007

In general, geotechnical properties have many uncertain aspects, thus probabilistic analysis have been used to consider these aspects. It is, however, quite difficult to select an appropriate target probability for a certain structure or construction process. In this study, minimum expected cost design method based on probabilistic analysis is suggested for design of vertical drains generally used to accelerate consolidation in soft clayey soils. A sensitivity analysis is performed to select the most important uncertain parameters for the design of vertical drains. Monte Carlo simulation is used in sensitivity analysis and probabilistic analysis. Total expected cost, defined as the sum of initial cost and expected additive cost, varies widely with variation of input parameters used in design of vertical drain systems. And probability of failure to get the minimum total expected cost varies under the different design conditions. A minimum value of total expected cost is suggested as a design value in this study. The proposed design concept is applicable to unit construction process because this approach is to consider the uncertainties using probabilistic analysis and uncertainties of geotechnical properties.

• Management Science and Financial Engineering
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• v.20 no.1
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• pp.17-19
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• 2014

In this paper, we consider an interesting variant of the inverse minimum traveling salesman problem. Given an instance (G, w) of the minimum traveling salesman problem defined on a metric space, we fix a specified Hamiltonian cycle $HC_0$. The task is then to adjust the edge cost vector w to w' so that the new cost vector w' satisfies the triangle inequality condition and $HC_0$ can be returned by the minimum spanning tree algorithm in the TSP-instance defined with w'. The objective is to minimize the total deviation between the original and the new cost vectors with respect to the $L_1$-norm. We call this problem the inverse metric traveling salesman problem against the minimum spanning tree algorithm and show that it is closely related to the inverse metric spanning tree problem.

• Journal of the Korea Society of Computer and Information
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• v.20 no.8
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• pp.105-112
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• 2015

Generally, the optimal solution of assignment problem has been obtained by Hungarian algorithm with O($n^3$) time complexity. This paper proposes more simple algorithm with O($n^2$) time complexity than Hungarian algorithm. The proposed algorithm simply selects minimum cost in each row, and classified into set S, H, and T. Then, the minimum cost is moved from S to T and $S{\rightarrow}H$, $H{\rightarrow}T$. The proposed algorithm can be obtain the same optimal solution as well-known algorithms and improve the optimal solution of partial unbalanced assignment problems.

• Journal of the Korean Home Economics Association
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• v.29 no.3
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• pp.35-45
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• 1991

This study was to calculate the minimum food expenditure by using OR linear program, and to determine the food plans for different income values based on the recommenced dietary allowances(RDA) for Koreans. VAX 11/780 system was used in this study. There were 6 family models-single man, single woman, married couple, couple with one child, couple with 2 children and couple with 2 children & grandmother. The market price quoted in this study was from July 1989 to June 1990 and the data file was made from RDA & food composition tables. After the minimum food expenditure was calculated from the computer, the low cost food plan was set. From the low cost food plan, we set the moderate cost food plan 25% above the low cost and the liberal food plan 50% above the low cost. One week menu was planned for different food plans. The low cost food plan could be used not only at the institutional levels and at home but also used at the national food policy making for scientific budget planning and for nutritionally well balanced diet. These food plans could control the use of time and efforts, too.

• IE interfaces
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• v.16 no.spc
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• pp.39-44
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• 2003

As one of many design variables, the role of dimension tolerances is to restrict the amount of size variation in a manufactured feature while ensuring functionality. In this study, a nonlinear integer model has been modeled to allocate the optimal tolerance to each individual feature at a minimum manufacturing cost. While a normal distribution determines statistically worst tolerances with its symmetrical property in many previous tolerance allocation studies, a asymmetrical distribution is more realistic because its mean is not always coincident with a process center. A nonlinear integer model is modeled to allocate the optimal tolerance to a feature based on a beta distribution at a minimum total cost. The total cost as a function of tolerances is defined by machining cost and quality loss. After the convexity of manufacturing cost is checked by the Hessian matrix, the model is solved by the Complex Method. Finally, a numerical example is presented demonstrating successful model implementation for a nonlinear design case.