• Journal of Korean Society for Quality Management
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• v.9 no.2
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• pp.44-51
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• 1981

The briquet is made of the coal. The calorie of briquet is 4370 kcal/kg by the law. The combination of coal is important for the manufacturing of briquet. We must know that the Test and Estimation of Calorie is necessary to study. The factory does not make the briquet by the experiment now, but they have made it properly by the experience. We know that the theoritical value of calorie resembles to the practical value of calorie. I think the factory must make a briquet certainly by the experiment. It is a best method for men to prevent from the crisis of briquet gas.

• Industrial Engineering and Management Systems
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• v.16 no.1
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• pp.109-117
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• 2017

In this article, a control chart based on multiple dependent (or deferred) state sampling for the gamma distributed quality characteristic is proposed using the gamma to normal transformation. The proposed control chart has two pairs of control limits, which can be determined by considering the in-control average run length (ARL). The shift in the scale parameter of a gamma distribution is considered and the out-of-control ARL is evaluated. The performance of the proposed chart has been shown for different levels of the parameters of the proposed control chart. It is also shown that the proposed chart is better than the Shewhart chart in terms of ARLs. A case study with a real data has been included for the practical usage of the proposed scheme.

• Toxicological Research
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• v.17
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• pp.17-24
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• 2001

Risk assessment is useful tool making good decisions on the risks of certain hazardous com-pound and suggests safe margin through scientific process using toxicological data, statistical tool, exposure value and relevant variants. The goal of risk management is to protect the public health from hazardous compound based on result of risk assessment having reality. For the suggestion of exact man-aging information, risk assessment must be designed to represent a "plausible estimate" of the exposure to the individuals and to minimize uncertainty. Risk assessment methodology and knowledge are expected to change more rapidly than before and up-to-date methodology should be applied in regulatory aspects through the Agency. For the useful application of risk assessment, the communication between the risk assessor and the risk manager is needed before the initiation of the risk assessment and upon its completion. Generally, the risk assessment itself as a practical tool in the regulatory decision making process would be regarded with social economic impact.ic impact.

• Toxicological Research
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• v.17
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• pp.211-216
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• 2001

Drugs can have various adverse effects on the immune system including unintended immun-osuppression, induction of both drug-specific immune responses (including drug allergies) and non-specific immunostimulation (including autoimmune reactions), and direct activation of effector mechanisms (such as histamine release). As a practical matter, the Center for Drug Evaluation (CDER) relies on standard non-clinical toxicology studies to detect unintended immunosuppression. Specific assays using guinea pigs and mice are available to identify drugs that can induce immune-mediated dermal hypersensitivity reactions. Respiratory and systemic hypersensitivity and autoimmune reactions are more difficult to model in non-clinical studies. Unintended nonspecific immunstimulation can be detected in animal studies. CDER is currently developing specific guidance for evaluating potential drug immunotoxicity.

• Journal of the Korean Operations Research and Management Science Society
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• v.21 no.1
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• pp.147-161
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• 1996

Generally the Multiprocessor Scheduling (MPS) problem is difficult to solve because of the precedence of the tasks, and it takes a lot of time to obtain its optimal solution. Though Genetic Algorithm (GA) does not guarantee the optimal solution, it is practical and effective to solve the MPS problem in a reasonable time. The algorithm developed in this research consists of a improved GA and GP/MISF (Critical Path/Most Immediate Successors First). An efficient genetic operator is derived to make GA more efficient. It runs parallel CP/MISF with GA to complement the faults of GA. The solution by the developed algorithm is compared with that of CP/MISF, and the better is taken as a final solution. As a result of comparative analysis by using numerical examples, although this algorithm does not guarantee the optimal solution, it can obtain an approximate solution that is much closer to the optimal solution than the existing GA's.

• Journal of the Korean Operations Research and Management Science Society
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• v.25 no.3
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• pp.1-15
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• 2000

In this paper, we propose a practical cut generation method based on the Chvatal-Gomory procedure for the (0, 1)-Knapsack problem with a variable capacity. For a given set N of n items each of which has a positive integral weight and a facility of positive integral capacity, a feasible solution of the problem is defined as a subset S of N along with the number of facilities that can satisfy the sum of weights of all the items in S. We first derive a class of valid inequalities for the problem using Chvatal-Gomory procedure, then analyze the associated separation problem. Based on the results, we develop an affective cut generation method. We then analyze the theoretical strength of the inequalities which can be generated by the proposed cut generation method. Preliminary computational results are also presented which show the effectiveness of the proposed cut generation method.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.05a
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• pp.200-207
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• 2003

Presented in this paper is a new fast and robust algorithm generating NC tool path for 2D pockets with islands. The input shapes are composed of line segments and cricular arcs. The algorithm has two steps: creation of successive offset loops and linking the loops to tool path. A modified pair-wise technique is developed in order to speed up and stabilize the offset process, and the linking algorithm is focused on minimizing tool retractions and preventing thin-wall rotting The proposed algorithm has been implemented In C++ and some illustrative examples are presented to show the practical strength of the algorithm.

• Journal of the Korean Operations Research and Management Science Society
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• v.35 no.1
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• pp.67-81
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• 2010

In Schumpeterian competition, superior profit arises from successful innovation created by firm's R&D strategy. Such R&D strategy diverges as time passes. This study examines empirically the effects of diverged forms of R&D strategy such as technological assets, technological diversity, and technological similarity on firm performance in Korean pharmaceutical industry. With the financial and patent data of 96 firms for 14 years from 1994 to 2007, we measured variables. And then we performed panel analysis with 3 years lag between dependent variable and other variables. The result shows that firm performance increases as technological asset and technological diversification increase. But technological similarity positively affects on firm performance in opposition to our hypothesis. We interpret and discuss these results and highlight the theoretical and practical implications of our findings.

• Journal of the Korean Operations Research and Management Science Society
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• v.34 no.3
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• pp.29-41
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• 2009

The purpose of this paper is to develop a new classification method for predicting consumer choice based on genetic algorithm, and to validate Its prediction power over existing methods. To serve this purpose, we propose a hybrid model, and discuss Its methodological characteristics in comparison with other existing classification methods. Also, we conduct a series of experiments employing survey data of consumer choices of MP3 players to assess the prediction power of the model. The results show that the suggested model in this paper is statistically superior to the existing methods such as logistic regression model, artificial neural network model and decision tree model in terms of prediction accuracy. The model is also shown to have an advantage of providing several strategic information of practical use for consumer choice.

• Management Science and Financial Engineering
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• v.16 no.3
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• pp.71-84
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• 2010

In this study, we present the exact methods of transforming the continuous solutions into the discrete ones for two types of bit-loading problem, marginal adaptive (MA) and rate adaptive (RA) problem, in multicarrier communication systems. While the computational complexity of existing solution methods for discrete optimal solutions depends on the number of bits to be assigned (R), the proposed method determined by the number of subcarriers (N), making ours be more efficient in most cases where R is much larger than N. Furthermore our methods have some strength of their simpler form to make a practical use.