• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.10
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• pp.1393-1398
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• 2012

Due to environmental regulation and technical improvements, renewable energy sources (RES) are increasingly penetrated and operated in power systems. Clean energy technologies have become cost-competitive with conventional power systems, and in the near future, the generation cost of RES is expected to approach grid parity. In this situation, it should be considered an extraordinarily important issue to be maximized resulting in utilization of RES as well as to develop technologies for efficiency improvement of RES. Therefore, in this paper, the method for determining an optimal installed capacity and interconnected location of RES is proposed in order to minimize the cost of energy not supplied, which can contribute to improve distribution reliability.

• Journal of Nutrition and Health
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• v.27 no.4
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• pp.368-377
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• 1994

The purpose of this study was to investigate determining factors which influence the riboflavin and pyridoxin nutritional status of korean newborns. The riboflavin and pyridoxine nutriture were evaluated by measuring the enzymecoenzyme saturation kinetics of erythrocyte glutathione reductase and alanine aminotransferase. The subjects were 259 newborns and their mothers. The average activity coefficent values of the cord blood EALAT was 1.4$\pm$0.11 and 32% of the samples had EALATAC values greater than 1.25. EGRAC was 1.26$\pm$0.12 and 27.4 of the blood samples had EALATAC values greater than 1.25. Vitamine B6 nutrition of the newborns whose mothers consumed more energy, protein and vitamine B6 was better as cord blood EALATAC values were found to the lower in this group. A stepwise multiple regression analysis showed that birth length and mother's age significantly influenced EGRAC values, positive and negative ways, respectively.

• The Transactions of the Korea Information Processing Society
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• v.7 no.7
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• pp.2188-2195
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• 2000

This paper deals with the problem of determining small-bands enclosing a given set of points on the sphere. The small-band is a spherical region, whose boundary is composed of two circles, and which does not contain any great circle. It is a kind of domains that is derived from formalizing the local accessibility problems for 3-axis NC machining into sperical containment problems so as to avoid the grouping. It also can be generated in 4- and 5-axis machine. When a set of points U and the size of a great-band are given, the methods for computing a feasible band and all feasible bands enclosing U in O(n) and O(n log n) time have been suggested, respectively. The methods can be applied into the cases of small bands since the solution region may contain holes. In this paper, we concentrate on the method for determining the smallest small-band enclosing U and suggest an O(n long n) time algorithm, where n is the number of points on the sphere.

• Korean Management Science Review
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• v.17 no.2
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• pp.125-134
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• 2000

Keeping the promised delivery date for a customer order is crucial for a company to promote customer satisfaction and generate further businesses. For this, a company should be able to quote the delivery date that can be achieved with the capacity available on the shop floor. In a dynamic make-to-order manufacturing environment, the problem of determining a delivery date for an incoming order with consideration of resource capacity, workload, and finished-product inventory can hardly be solved by an analytical solution procedure. This paper considers a situation in which a delivery date for a customer order is determined based on a job schedule, and presents the SimTriD algorithm that provides the best scheduling for determining a delivery date of customer order through the job schedule that efficiently utilizes manufacturing resources with consideration of interacting factors such as resource utilization, finished-product inventory, and due date.

• International Journal of Highway Engineering
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• v.18 no.4
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• pp.63-68
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• 2016

PURPOSES : The nonlinear model of fatigue cracking is typically used for determining the maintenance period. However, this requires that the model parameters be known. In this study, the particle filter (PF) method was used to determine various statistical parameters such as the mean and standard deviation values for the nonlinear model of fatigue cracking. METHODS : The PF method was used to determine various statistical parameters for the nonlinear model of fatigue cracking, such as the mean and standard deviation. RESULTS : On comparing the values obtained using the PF method and the least square (LS) method, it was found that PF method was suitable for determining the statistical parameters to be used in the nonlinear model of fatigue cracking. CONCLUSIONS : The values obtained using the PF method were as accurate as those obtained using the LS method. Furthermore, reliability design can be applied because the statistical parameters of mean and standard deviation can be obtained through the PF method.

• Journal of applied mathematics & informatics
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• v.35 no.5_6
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• pp.439-447
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• 2017

This paper investigates the inverse problem of determining an unknown heat radiative coefficient, which is only time-dependent. This is an ill-posed problem, that is, small errors in data may cause huge deviations in determining solution. In this paper, the existence and uniqueness of the problem is established by the second Volterra integral equation theory, and the method of trace-type functional formulation combined with finite difference scheme is studied. One typical numerical example using the proposed method is illustrated and discussed.

• Journal of Electrical Engineering and Technology
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• v.10 no.2
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• pp.511-517
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• 2015

Determination of the required reserve capacity has an important function in operation of power system and it is calculated based on the largest loss of supply. However, conventional method cannot be applied in future power system, because potential grid-connected distributed generator and abnormal temperature cause the large load imbalance. Therefore this paper address new framework for determining the optimal required reserve capacity taking into account the real time load imbalance. At first, we introduce the way of operating reserve resources which are the secondary, tertiary, Direct Load Control (DLC) and Load shedding reserves to make up the load imbalance. Then, the formulated problem can be solved by the Probabilistic Dynamic Programming (PDP) method. In case study, we divide two cases for comparing the cost function between the conventional method and the proposed method.

• Journal of Korean Institute of Industrial Engineers
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• v.6 no.2
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• pp.31-36
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• 1980

This paper proposes a very simple algorithm for determining the parameters in the economic design of s-charts. These parameters are the sample size, the factor determining the spread of the control limit and the sampling interval. Several examples show that the parameters determined by this algorithm are very close to the exact optimal values.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.6
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• pp.963-968
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• 2013

In this study, we carried out a structural analysis for determining the stresses acting on the tempered glass of a freely falling cellular phone using ANSYS 13.0, commercial finite element code. We designed a phone heavier than any contemporary cellular phone and performed finite element analysis using the falling speed at a height of 104 cm, which is equal to of the average leg length of Koreans. By determining the maximum stress acting on the phone's tempered glass and frame, we identified the location of large deformation. Furthermore, we evaluated the maximum/minimum equivalent stress and deformation of the reinforced glass and frame as functions of time.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.11
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• pp.108-116
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• 2003

In this paper, based on the concept of solid particles' sediment problem the working formula determining the bowl length of a Decanter-type centrifuge were derived. Assuming that particles are uniformly distributed along the vertical line of the liquid inlet position, it was possible to derive a constant value k used for determining the bowl length. It was shown from the sample calculations that the bowl length should be increased as the particle size to be removed from the liquid is decreased. The length also should be increased for the same particle size as the bowl diameter is decreased. To help the engineers choose a reasonable bowl diameter, the statistical relationship between the bowl diameter and the capacity of the international products is obtained and presented.