• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.04a
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• pp.154-159
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• 1997

This paper describes the electron transport characteristic in SiH$_4$ gas calculated for range of E/N values from 0.5~300(Td) by the Monte Calro simulation and Boltzmann equation method using a set of electron collision cross sections determined by the authors and the values of electron swarm parameters are obtained for TOF method. The results gained that the value of an electron swarm parameter such as the electron drift velocity, the electron ionization coefficients longitudinal and transverse diffusion coefficients, characteristics energy agree with thee experimental and theoretical for a range of E/N. The electron energy distributions function were analysed in monosilane at EN : 30, 50(Td) for a case of equilibrium region in the mean electron energy. The validity of the results obtained has been confirmed by a TOF method.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.280-281
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• 2006

This paper was analyzed fundamental about electrical characteristic of concrete to practical use base of building as Substitution Ground Electrode and Artificial Ground Electrode. 1) Gravel or Sand has a function that makes increase Resistivity of Concrete and Cement has a function that makes decrease Resistivity of Concrete. 2) Moisture Increase Work is so hard because of dry of Block but the Resistivity was decreased when the moisture of Concrete Block was gradually increased. 3) According to the measurement result of moltar and concrete block, ratio relation of Resistance and Resistivity of each block was thirty-fold difference.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.664-669
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• 2005

In this note, we present a different asymptotes from the standard approximate lines of the Bode magnitude plot. Wherein the pseudo break frequency is defined in terms of coefficients of denominator and numerator polynomials of the transfer function instead of its poles and zeros. Several comparative examples are given. This result can be used for the characteristic ratio assignment(CRA) [1], [2] with frequency response requirements, which is a method of designing linear controller in parameter space.

• International Journal of Reliability and Applications
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• v.4 no.3
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• pp.97-111
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• 2003

By applying Theorem 2.6.4 (Fang and Zhang, 1990, p.66) the dispersion matrix of a multivariate power exponential (MPE) distribution is derived. It is shown that the MPE and the gamma distributions are related and thus the MPE and chi-square distributions are related. By extending Fang and Xu's Theorem (1987) from the normal distribution to the Univariate Power Exponential (UPE) distribution an explicit expression is derived for calculating the probability of an UPE random variable over an interval. A representation of the characteristic function (c.f.) for an UPE distribution is given. Based on the MPE distribution the probability density functions of the generalized non-central chi-square, the generalized non-central t, and the generalized non-central F distributions are derived.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.82-85
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• 2006

A trapezoidal fin with various lateral surface slopes is designed optimally by using one-dimensional analytic method. For four different convection characteristic numbers, the trend of heat loss as a function of fin tip length is shown. The optimum heat loss is somewhat arbitrarily chosen as 92% of the maximum heat loss. The optimum fin length corresponding to this optimum heat loss versus convection characteristic number is presented. The optimum effectiveness and specific effectiveness is presented as a function fin shape factor.

• Journal of Korean Society for Quality Management
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• v.30 no.1
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• pp.61-73
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• 2002

The Quality Function Deployment(QFD) is a Quality Management technique to maximize customers' satisfaction by reflecting customer requirements into all business processes, including concept definition, product planning, parts planning, process planning, production planning, and sales planning. The basic concept of the QFD is to translate customers' requirements appropriately into engineering characteristics, into parts characteristics, into process characteristics, and into specific requirements and activities in production. In this study, we reviewed and analyzed the application process of the QFD to the development of A2 FATC (Full Automatic Temperature Controller), an automotive component developed and produced by company A. It has been reported that by applying the QFD to the development of A2 FATC, company A. achieved 34% improvement in control robustness quality characteristic, 27% improvement in deviation quality characteristic, and 30% improvement in overall quality characteristics.

• Journal of the Korean Data and Information Science Society
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• v.15 no.4
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• pp.867-877
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• 2004

The sequential sampling inspection method is an extension of the multiple-sampling methods, and its theory is based on the sequential probability ratio test (SPRT) of Wald. In this paper, the characteristics of SPRT for testing the number of defects are approximated by using the estimated excess over the boundaries. The use of the estimated excess shows good performances in estimating the operating characteristic function and the average sample number of SPRT compared to the method by neglecting the excess. It also makes it possible to determine the boundary values which satisfy the desired error probabilities.

• Journal of Korean Society for Quality Management
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• v.27 no.2
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• pp.126-142
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• 1999

Robust design is an approach to reducing performance variation of quality characteristic values in quality engineering. Taguchi has an idea that mean and variation are handled simultaneously to reduce the expected loss in products and processes. Taguchi parameter design has a great deal of advantages but it also has some disadvantages. The various research efforts aimed at developing alternative methods. In the Taguchi parameter design, the product-array approach using orthogonal arrays is mainly used. However, it often requires an excessive number of experiments. An alternative approach, which is called the combined-array approach, was suggested by Welch et. al. ( 1990) and studied by others. In these studies, only single quality characteristic was considered. In this paper we propose how to simultaneously optimize multiple quality characteristics using desirability function when we used the combined-array approach to assign control and noise factors. An example is illustrated to show the difference between the Taguchi's product-array approach and the combined-array approach.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.169-174
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• 1996

In this paper, the electron transport characteristic in CF$_4$has been analysed over the E/N range 1~300(Td) by a two-term approximation Boltzmann equation method and by a Monte Carlo simulation. The alteration of cross sections from the literature is avoided as much as possible in the analysis. The motion has been calculated to give swarm parameters for the electron drift velocity(W), diffusion coefficient(D$_{L}$), the ratio of the diffusion coefficient to the mobility(D$_{L}$/$\mu$), mean energy($\varepsilon$), the electron energy distribution function. The electron energy distribution function has been analysed in CF$_4$at E/N=50, 100 and 200(Td) for a case of the equilibrium region in the mean electron energy. The results of Boltzmann equation and Monte Carlo simulation have been compared with experimental data by Y. Nakamura and M. Hayashi.shi.

• Journal of the Korean Chemical Society
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• v.6 no.1
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• pp.36-46
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• 1962

The author assumes that pure liquid metal is composed of molecular oscillators whose energy states are classified into two subgroups, i.e., A and B states, each being accesible to either one of the two sorts of lattice sites. The partition function involves constants characteristic of substance, which are obtainable from the Debye characteristic temperature assigned to its solid state. Calculation has been made for the various thermodynamic properties such as the vapor pressure, the entropy, and the heat capacity of liquid metals of GroupⅠelements over the temperature range from the melting points to the boiling points. The theoretical values thus obtained are in good accordances with those observed, within experimental error, although a slight derivation is observed in the atomic heat capacity.