• Journal of the Korean Society for Precision Engineering
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• v.6 no.1
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• pp.33-44
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• 1989

A controller disign method is proposed for multivariable nonlinear stochastic systems with hard nonlinearities such as Coulomb friction, backlash and saturation. In order to take the nonlinearities into account statistical linearization techniques are used. And multi- variable pole placement techniques are applied to design controller for the statistically linearized multivariable systems. The basic concept of the controller design method is to solve two coupled equations, characteristic equation and Lyapunov equation, simultaneously and iteratively for statistically linearized multivariable stochastic systems. An aircraft with saturation serves as a design example. The design example illustrates the influence of nonlinear effects. The results of the analysis are compared to Monte Carlo simulation to test their accuracy.

• Korean Journal of Head & Neck Oncology
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• v.33 no.1
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• pp.7-13
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• 2017

Despite improved treatment outcomes of locally advanced disease over the last 2 decades, the survival of patients with recurrent and/or metastatic head and neck squamous cell carcinoma (HNSCC) remains dismal. There is a clear need for development of novel therapeutic strategies for recurrent and/or metastatic HNSCC. Recent advances in understanding tumor immunology have been directly and rapidly translated into clinical success of T cell-directed immunotherapeutic approach in the treatment of several types of solid cancers. Among them, impact of immune checkpoint inhibition using neutralizing antibodies is the most striking. A variety of immunotherapeutic strategies targeting T cells have been also studied in HNSCC, especially in recurrent and/or metastatic setting even with significant survival benefit. The present article reviews the basic concept of T cell-directed immunotherapy and the current status of such approaches in the treatment of HNSCC.

• Korean Journal of Agricultural and Forest Meteorology
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• v.2 no.1
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• pp.24-30
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• 2000

This paper is to introduce distinctive trends in Agrometeorological Information(AgMI) these days, as well as newly emerging technologies from advanced sciences that are promising to enhance production and dissemination of AgMI in the future. The basic concept and important characteristics of AgMI were described either in general or in technical terms. Then AgMI was rather arbitrarily classified here into several groups, simply to show the diversity of AgMI resources available and technologies employed. The production, management, dissemination and communication of AgMI are envisaged to some extent together with the introduction of current status of AgMI production in Korea. Finally a couple of personal prospects on AgMI for agricultural applications are listed in terms of applicable subjects in Agricultural activities, current practicing cases in Korea and future perspectives for sustainable agriculture.

• Journal of Korean Society for Quality Management
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• v.18 no.1
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• pp.65-76
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• 1990

A lot-sizing model for multi-stage MRP systems is proposed, in which known demands must be satisfied. In this model, an approach with considerations of initial inventory and limited production capacity is involved. Most of the studies on the lot-sizing techniques for multi-stage material requirement planning systems have been focused upon two basic approaches. One approach is to develope an algorithm yielding an optimal solution. Due to the computational complexity and sensitivity of the optimal solution to the problem of lot sizing, heuristic approaches are often employed. In this paper, the heuristic approach is used by sequential application of a single-stage algorithm with a set of modified cost by the concept of multi-echelon costs. The proposed method is compared with an lot-sizing method(Florian-Klein Model) to prove its effectiveness by numerical examples.

• Communications for Statistical Applications and Methods
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• v.10 no.1
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• pp.153-166
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• 2003

This study presents the time-divided forecasting model to integrate evolutionary optimization algorithm and change point detection based on artificial neural networks (ANN) for the prediction of (Korea) stock price index. The genetic algorithm(GA) is introduced as an evolutionary optimization method in this study. The basic concept of the proposed model is to obtain intervals divided by change points, to identify them as optimal or near-optimal change point groups, and to use them in the forecasting of the stock price index. The proposed model consists of three phases. The first phase detects successive change points. The second phase detects the change-point groups with the GA. Finally, the third phase forecasts the output with ANN using the GA. This study examines the predictability of the proposed model for the prediction of stock price index.

• Journal of Welding and Joining
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• v.28 no.1
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• pp.72-76
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• 2010

Irregular fluctuation of penetration depth in CW single mode fiber laser welding is analyzed statistically and chaotically. Among various chaos theories, one of the basic concept referred as Lyapunov exponent is applied to the analysis to quantify the irregularity of penetration. Especially, maximal Lyapunov exponent (MLE) is known as the representative value indicating chaotic degree of the system dynamics. MLE calculation method of experimental data is applied to longitudinal spiking defect in fiber laser weld. Laser power modulation is suggested as a remedy then the computed MLE value is compared to CW case. It is shown that the adoption of chaos theory, MLE computation, can be used as a measurement standard to prove the validity of the solutions to prevent the unexpected chaotic behavior of weld through this work.

• Communications of Mathematical Education
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• v.21 no.4
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• pp.597-612
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• 2007

For finding the optimal strategy in Blackout game which was introduced in the homepage of popular movie "Beautiful mind", we have developed and generalized a mathematical proof and an algorithm with a couple of softwares. It did require only the concept of basis and knowledge of basic linear algebra. Mathematical modeling and analysis were given for the square matrix case in(Lee,2004) and we now generalize it to a generalized $m{\times}n$ Blackout game. New proof and algorithm will be given with a visualization.

• Journal of the Korean Society of Clothing and Textiles
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• v.16 no.3 s.43
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• pp.315-323
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• 1992

The purpose of this research is the new experimental approach to the methodology of the costume history 'study. The basic frame is structured by the concept of the type. This is developed to the decoration type of the costume, originated by the classification of the decoration type of Ruskin. Using this, the researcher could analysis the decoration type of the costumes in the 19th century. In the result, the researcher could find that the change of the decoration type had the regular orientation of the oscillation through the periods. It is the experimental frame for the analysis of the styles. But it will provide the more extensive analytical frame on condition that catagorizations are completed. And it will be able to imply to the 20th century's costume.

• Journal of the Korean Society of Clothing and Textiles
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• v.17 no.4
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• pp.602-607
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• 1993

Concept of the comfort and fitness becomes a major concern in the basic function of the ready-made clothes. This research was performed to classify and characterize Korean adult males anthropometrically. Sample size was 1290 subjects and their age range was from 19 to 54 years old. Sampling was carried out by the stratified sampling method. 75 variables in total were applied to classify the bodytypes. Data were analyzed by the multivariate method, especially factor and cluster analysis. The high factor loading items extracted by factor analysis were based to determine the variables of the cluster analysis for the similar bodytypes respectively. In the part of the lower body, 14 variables from the data were applied to classify the bodytypes of lower part by Ward's minimum variance method. The group fanning a cluster were subdivided into 5 sets by cross-tabulation extracted by the hierarchical cluster analysis. Type 3 and 4 in lower body were composed of the majority of 53.1% of the subjects. The Korean adult males had relatively well-balanced in lower body.

• Journal of Environmental Impact Assessment
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• v.8 no.1
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• pp.141-146
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• 1999

This paper proposes the planning and design of the Eco-village centering around Chindo-ri, Muju-kun. The Eco-village project has three basic objects the Eco-village residents' lives adapting to ecological principles such as regeneration and circulation, life agricultural techniques based on organic cycle, and residents' harmonious lives with the surrounding nature. For constructing of the Eco-village, first, the subject area was analyzed in terms of the natural and cultural environment and then, on this analytic ground the concrete concept and the specific plan were set up. The following details also should be considered: the scale of the residential household, the population, the space arrangement of the village, the material cycling structure, the waste treatment, the purification of the sewage, the energy supply, the landscape architecture, the production activity, the conservation of the ecosystem and so on.