• Proceedings of the Korean Society for Bioinformatics Conference
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• 2004.11a
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• pp.272-278
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• 2004

Recently, Pepe et al. (2003) employed the receiver operating characteristic (ROC) approach to rank candidate genes from a microarray experiment that can be used for the biomarker development with the ultimate purpose of the population screening of a cancer, In the cancer microarray experiment based on n patients the researcher often wants to compare the tumor tissue with the normal tissue within the same individual using a common reference RNA. This design is referred to as a reference design or an indirect design. Ideally, this experiment produces n pairs of microarray data, where each pair consists of two sets of microarray data resulting from reference versus normal tissue and reference versus tumor tissue hybridizations. However, for certain individuals either normal tissue or tumor tissue is not large enough for the experimenter to extract enough RNA for conducting the microarray experiment, hence there are missing values either in the normal or tumor tissue data. Practically, we have $n_1$ pairs of complete observations, $n_2$ 'normal only' and $n_3$ 'tumor only' data for the microarray experiment with n patients, where n=$n_1$+$n_2$+$n_3$. We refer to this data set as a mixed data set, as it contains a mix of fully observed and partially observed pair data. This mixed data set was actually observed in the microarray experiment based on human tissues, where human tissues were obtained during the surgical operations of cancer patients. Pepe et al. (2003) provide the rationale of using ROC approach based on two independent samples for ranking candidate gene instead of using t or Mann -Whitney statistics. We first modify ROC approach of ranking genes to a paired data set and further extend it to a mixed data set by taking a weighted average of two ROC values obtained by the paired data set and two independent data sets.

• Cartoon and Animation Studies
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• s.25
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• pp.87-108
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• 2011

Published comics are widely recognized as a popularity-gaining media as well as Soap opera and the movies, and it also has a established characteristic of category. However, compare to the multimedia such as the movies, soap opera and playes, the research on direction is not yet satisfactory This research mainly tries to investigate on, first, whether the theoretically classified functions do actually practice their parts or not, and else, what other additional functions should be considered, by classifying the set up of basic direction functions, angles and range, which the most-cited angle and distance notion of 'Ahn Su Cheol' in comic education field. First, although we tried to approach with the expectation of angle and distance set up that will have a high frequency of certain set ups according to the atmospheres of comics of genre, unlike the expectation, they are rather displayed depending on the personal taste of the writers. The functional aspects of angles and distance set up are the fixing that are only limited in the space of representation, and it is the set up of physical space that should come first as the function of expressing the intensity. As we investigate the characteristics of comic direction, this research will help the range of comic direction to be broadened.

• Proceedings of the Korean Society for Quality Management Conference
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• 1998.11a
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• pp.556-567
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• 1998

Robust design in industry is an approach to reducing performance variation of quality characteristic value in products and processes. Taguchi has used the signal-to-noise ratio(SN) to achieve the appropriate set of operating conditions where variability around target is low in the Taguchi parameter design. Taguchi has dealt with having constraints on both the mean and variability of a characteristic (the dual response problem) by combining information on both mean and variability into an SN. Many Statisticians criticize the Taguchi techniques of analysis, particularly those based on the SN. In this paper we propose a substantially simpler optimization procedure for robust design to solve the dual response problems without resorting to SN. Two examples illustrate this procedure. in the two different experimental design(product array, combined array) approaches.

• Proceedings of the KIEE Conference
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• 2008.04c
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• pp.215-217
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• 2008

This paper describes development of hardware simulator for the PMSG wind power system, which was designed considering wind characteristic, blade characteristic and blade inertia compensation. The simulator generates torque and speed signals for a specific wind turbine with respect to given wind speed. This torque and speed signals are scaled down to fit the input of 2kW PMSG. The PMSG-side converter operates to track the maximum power point, and the grid-side inverter controls the active and reactive power supplied to the grid. The operational feasibility was verified by computer simulations with PSCAD/EMTDC, and the implementation feasibility was confirmed through experimental works with a hardware set-up.

• Journal of Power System Engineering
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• v.5 no.3
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• pp.17-24
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• 2001

In order to investigate a characteristic of the behavior of spray pattern in accordance with running conditions for a DI diesel engine, the PLN Injection system with changeable revolution speed of fuel injection cam was set up, and through this, history curves of injection pressure for a similar real DI diesel engine were able to be displayed. Authors visualized and analyzed the sprays at various revolution speed of fuel injection cam, and found out that fuel distributions of the sprays in the low speed condition were bad, fuel with air was injected from the hole of nozzle at the beginning of injection, and wide spray angle at the early stage of injection became narrower with elapsed time, but wider again at the end of injection.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.789-794
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• 2001

The acoustic emission(AE) signal from concrete cylinder specimen during failure process under cycling compressive loads were recorded and analyzed. Different filters were set on the AE signal duration based on the characteristic of amplitude distribution. From the value of AE signal amplitude, which corresponds to the occurrence of the peak for AE hits, the AE signals from concrete compressive specimen were divided into five sections. The relationship between the AE signal section and the failure mechanism of these materials, analyzed on the meso-structure level was determined. Based on the experiments, the AE characteristics of each failure mechanism are given. The results show that the AE technique is a valuable tool to study the failure mechanism of concrete.

• Journal of Korean Society for Quality Management
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• v.12 no.2
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• pp.15-24
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• 1984

Since W.A. Shewhart (1931) developed the quality control method using the control chart, many theoretical and empirical works about such an analytical method have been done. However there are two major methods relating to the control chart analysis; the conventional 3 sigma control method and the warning limit method which has been suggested as a modification of the former. The conventional 3 sigma method requires to take a remedial action only when a quality characteristic is beyond the control limit (3 sigma). However, once a quality characteristic is over the control limit, searching and repairing an assignable cause requires time consuming job and high costs. Therefore if we set the warning limit between the central line and the control limit, we will be able to take remedial measures before too late. In spite of its advantage, much attention has not been paid to use the control chart with warning limit in Korean industries. The main object of this study is to examine improvement of quality and productivity when the control chart with warning limit is used.

• Korean Management Science Review
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• v.11 no.2
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• pp.237-253
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• 1994

Technology measurement is related with how to construct indicators of technological change and relative ranking of technological sophistication. Many attempts have been made to understand the measurement of technology. However, technology measurement still remains little understood problem in spite of its importance. This article is concerned with improving the measurement of technology by introducing market factors into the model. It illustrate a simple approach to the measurement of technology. This approach is based on the characteristic-space paradigm of technology. A relative ranking of technological sophistication for a product is measurable as a set of characteristics. The main feature of the proposed approach is the combination of technical factors and market factors. Technical factors are reflected in the definition of technological sophistication. Market factors are embraced in the determination of the relative importance assigned to each technology defining characteristics. Thus, the weight is determined by technical factors and market factors, which differentiates the study from the past based on judgmental technique such as experts' opinion.

• Journal of Korean Society for Quality Management
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• v.26 no.4
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• pp.88-100
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• 1998

Robust design in industry is an a, pp.oach to reducing performance variation of quality characteristic value in products and processes. Taguchi has used the signal-to-noise raio(SN) to achieve the a, pp.opriate set of operating conditions where variablity around target is low in the Taguchi parameter design. Taguchi has dealt with having constraints on both the mean and variability of a characteristic (the dual response problem) by combining information on both mean and variability into an SN. Many Statisticians criticize the Taguchi techniques of analysis, particularly those based on the SN. In this paper we propose a substantially simpler optimization procedure for robust design to solve the dual response problems without resorting to SN. Two examples illustrate this procedure in the two different experimental design(product array, combined array) a, pp.oaches.

• 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.