• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.11
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• pp.2035-2051
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• 2011

Theoretical Bit Error Rate (BER) and channel capacity analysis are always of great interest to the designers of wireless communication systems. At the center of such analyses people are often encountered with a high-dimensional multiple integrals with quite complex integrands. Conventional Gaussian quadrature is inefficient in handling problems like this, as it tends to entail tremendous computational overhead, and the principal order of its error term increase rapidly with the dimension of the integral. In this paper, we propose a new approach to calculate complex multi-fold integrals based on the number theory. In contrast to Gaussian quadrature, the proposed approach requires less computational effort, and the principal order of its error term is independent of the dimension. The effectiveness of the number theory based approach is examined in BER and capacity analyses for practical systems. In particular, the results generated by numerical computation turn out in good match with that of Monte-Carlo simulations.

• Earthquakes and Structures
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• v.8 no.5
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• pp.1055-1067
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• 2015

A theoretical procedure to estimate spectral displacement of a hysteretic oscillator with bilinear stiffness excited by band-limited excitation is presented. The stochastic method of ground-motion simulation is combined with the random vibration theory to compute linear and nonlinear structural response. The response is obtained by computing the root-mean-square oscillator response using dissipation energy balancing by integrating over all energy levels of system weighting with the stationary probability density of the energy. The results are presented in a convenient form, and the accuracy of the procedure is assessed by comparison with results obtained with the time-domain method using the recorded data. The model shows little or no bias at the structural period of engineering interest.

• Journal of Astronomy and Space Sciences
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• v.23 no.2
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• pp.135-142
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• 2006

The extension of sunspot number series and auroral observations backward in time is of considerable interest for dynamo theory, solar activity and climate research. It was known that the Maunder minimum corresponded to a unusual cold so called little ice age in Europe and the appearance of sunspot had a close relation to the occurrence of aurora. Therefore we have examined ancient records of sunspots and aurorae with indirect solar proxies during this period and have studied for the features and peculiarities of solar activity with the relation of the climate variation.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.29B no.7
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• pp.79-86
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• 1992

Recent research on the application of fuzzy set theory to the design of control systems has led to interest in the theory of decomposition of multivariable fuzzy systems. Decomposition of multivariable control rules is preperable since it alleviates the complexity of the problem. However inference error is inevitable because of its approximate nature. In this paper we define an index of applicability which can classify whether the Gupta et. al's method can be applied to multivariable fuzzy system or not. We also propose a modified version of the decomposition which can reduce inference error and improve performance of the system.

• Korea Journal of Hospital Management
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• v.21 no.3
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• pp.53-64
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• 2016

The study empirically examines the classic hypothesis on resource-based view(RBV) theory, which is the possible relationship between competitive advantage and performance. For the study, we have surveyed 198 hospital administrators in Korea. By testing the hypotheses at conceptual level, a more robust approach, we found that (1) if a hospital possesses and exploits resources and capabilities that are both valuable and rare, it will attain a competitive advantage, and (2) the attaintment of such advantage will enable the hospital to improve its performance. The results may be interest to both academics and practitioners. From an academic standpoint, the study more accurately captures the dynamics of the theory by pairing resources-capabilities as opposed to individual resources or capabilities. From a practitioner perspective, it is suggested that hospital managers need no necessarily seek out novel resources and capabilities, but rather develop novel ways in which to combine those resources and capabilities to which they do have access.

• Research in Community and Public Health Nursing
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• v.8 no.2
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• pp.314-326
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• 1997

In Korea, the nosocomial infection control program is not well developed. This situation is created by a lack of interest from medical personnel and the medical payment system. This study identifies current problems and develops a model for nosocomial infection control. The studies of Lee & Kim(1995), Lee (1993) and SENIC project model were used to construct this model. 1. The problems of nosocomial infection control were identified as the following: dis approval by hospital authorities, lack of sources for program direction, lack of overall structure and function in the program, inadequate direct action, lack of education and training, and so on. 2. The problems are reorganized according to the 5 elements of system theory. 3. As a result, the new nosocomial infection control model was developed. The inputs of the model were the elements, resources and boundaries of nosocomial infection. With the new model, each hospital can evaluate their current programs and plan a new program for the better control of nosocomial infection.

• Journal of the Korean Society for Library and Information Science
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• v.41 no.1
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• pp.273-287
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• 2007

The purpose of this paper is that which behavior is affected by the storytelling for the visually impaired children. I had a depth interview with the children and their parents who were Participated in the storytelling class, the storytelling teacher and the librarian. And then the material was analysed by the grounded theory. As a result of this research, storytelling is very helpful for the visually impaired children to improve their interest in reading, learning ability and their sociality.

• Journal of Ship and Ocean Technology
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• v.1 no.2
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• pp.1-10
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• 1997

The prediction of the total resistance of a ship is generally based on considering it to be a simple sum of the viscous resistance and the wave resistance. An experimental approach for predicting full-size ship resistance on this basis is practical but obviously has the deficiency that a model has to be built for each prototype of interest and the resulting tank tests are time consuming. On the other hand, purely theoretical calculations of the wave resistance, using, for example, the Michell theory, require relatively little computer time and give an excellent portrayal of the overall variation of the vessel resistance as a function of forward speed. Unfortunately, there are sufficient differences between this theory and the measured results to make this method impractical for design purposes. The proposal examined here is to use a data bank of experimental resistance results to modify the theoretical predictions. It is demonstrated that the technique will produce remarkably accurate resistance predictions and can take into account the effects of the water depth, any restriction of canal or river width, as well as the prismatic coefficient, and other geometric parameters.

• Journal of Korean Society for Quality Management
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• v.32 no.1
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• pp.102-112
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• 2004

Keep in step in trend that interest for brand is rising and enterprise should tries to customer to Inform own brand. The mayor is diversified and work this which make correct product or brand on customer need is work which our enterprise does now. And should judge the availability whether customer is satisfied to product according to the brand. Because this can be the most important matter which is kept customer and create profit that is enterprise's ultimate object. In this study, customer measured brand enforcing to blue jeans clothing company how is recognizing and distinguishes brand forefinger to low rank group with high position group. And, measured satisfaction by each group. Measured new concept that is when enforce customer satisfaction, expectation which is existent theory, result, Involvement with inconsistency theory making grafting and confirmed that involvement is factor influencing in customer satisfaction measurement.

• International Journal of Precision Engineering and Manufacturing
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• v.3 no.1
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• pp.43-48
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• 2002

This paper describes an automated computer-aided engineering (CAE) system for three-dimensional structures. An automatic finite element mesh-generation technique, which is based on fuzzy knowledge processing and computational geometry techniques, is incorporated into the system, together with a commercial FE analysis code, and a commercial solid modeler. The system allows a geometry model of interest to be automatically converted to different FE models, depending on the physical phenomena of the structures to be analyzed, i.e., electrostatic analysis, stress analysis, modal analysis, and so on. Also, with the aid of multilayer neural networks, the present system allows us to obtain automatically a design window in which a number of satisfactory design solutions exist in a multi-dimensional design parameter space. The developed CAE system is successfully applied to evaluate an electrostatic micromachines.