• Annual Conference of KIPS
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• 2001.10a
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• pp.535-538
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• 2001

Since 1990s, many literatures have shown that connectionist models, such as back propagation, recurrent network, and RBF (Radial Basis Function) outperform the traditional models, MA (Moving Average), AR (Auto Regressive), and ARIMA (Auto Regressive Integrated Moving Average) in time series prediction. Neural based approaches to time series prediction require the enough length of historical measurements to generate the enough number of training patterns. The more training patterns, the better the generalization of MLP is. The researches about the schemes of generating artificial training patterns and adding to the original ones have been progressed and gave me the motivation of developing VTG schemes in 1996. Virtual term is an estimated measurement, X(t+0.5) between X(t) and X(t+1), while the given measurements in the series are called actual terms. VTG (Virtual Tern Generation) is the process of estimating of X(t+0.5), and VTG schemes are the techniques for the estimation of virtual terms. In this paper, the alternative VTG schemes to the VTG schemes proposed in 1996 will be proposed and applied to multivariate time series prediction. The VTG schemes proposed in 1996 are called deterministic VTG schemes, while the alternative ones are called stochastic VTG schemes in this paper.

• Journal of Korea Technology Innovation Society
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• v.7 no.3
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• pp.657-679
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• 2004

The purpose of this paper is to measure economic impact of marine environment conservation research development project. Benefit-Cost(B/C) analysis and Contingent Valuation Methods(CVM) are used to valuate the benefits from the research development projects. A period of three years for research development fund is considered as a part of the costs and adjusted to the net present value (NPV) of the 2002 ending period. The environmental charges for marine environment improvement are considered for the benefit measurement. The benefits are estimated by using monthly average willingness to pay, which is 2,289 Korean won. The contribution of the developing a management model for environmental pollution in the Gwangyang Bay is evaluated utilizing survey data and information. Based on the assessment by expert groups, the contribution of the model was 37.5％. The research results showed that B/C ratio is 20.61, NPV is 89,200 million Korean won, and social rate of return is 185.7％. When the level of contribution is over 1.83％ at the assessment of potential influence, it is recognized to be economically feasible. This research presents a quantitative framework for Research and Development projects for marine environment conservation, and it can be applied to decision making for the investment size of R&D projects.

• Journal of Power Electronics
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• v.6 no.2
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• pp.104-113
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• 2006

Satellites have provided the impetus for the orderly development of reliability engineering research and analysis because they tend to have complex systems and hence acute problems. They were instrumental in developing mathematical models for reliability, as well as design techniques to permit quantitative specification, prediction and measurement of reliability. Reliability engineering is based on implementing measures which insure an item will perform its mission successfully. The discipline of reliability engineering consists of two fundamental aspects; $(1^{st})$ paying attention to details, and $(2^{nd})$ handling uncertainties. This paper uses some of the basic concepts, formulas and examples of reliability theory in application. This paper emphasizes the practical reliability analysis of a Low Earth Orbit (LEO) Micro-satellite power subsystem. Approaches for specifying and allocating the reliability of each element of the power system so as to meet the overall power system reliability requirements, as well as to give detailed modeling and predicting of equipment/system reliability are introduced. The results are handled and analyzed to form the final reliability results for the satellite power system. The results show that the Electric Power Subsystem (EPS) reliability meets the requirements with quad microcontrollers (MC), two boards working as main and cold redundant while each board contains two MCs in a hot redundant.

• Journal of Information Processing Systems
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• v.4 no.4
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• pp.121-132
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• 2008

VLSI chips have been tested using various automatic test equipment (ATE). Although each ATE has a similar structure, the language for ATE is proprietary and it is not easy to convert a test program for use among different ATE vendors. To address this difficulty we propose a tester structure expression language, a tester language with a novel format. The developed language is called the general tester language (GTL). Developing an interpreter for each tester, the GTL program can be directly applied to the ATE without conversion. It is also possible to select a cost-effective ATE from the test program, because the program expresses the required ATE resources, such as pin counts, measurement accuracy, and memory capacity. We describe the prototype environment for the GTL and the tester selection tool. The software size of the prototype is approximately 27,800 steps and 15 manmonths were required. Using the tester selection tool, the number of man-hours required in order to select an ATE could be reduced to 1/10. A GTL program was successfully executed on actual ATE.

• Journal of Oriental Neuropsychiatry
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• v.19 no.1
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• pp.71-81
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• 2008

Objective: Obesity threatens not only the problem of beauty but also health. Furthermore, it could be harmful a chronic disease to increase mortality rate. A purpose of this study is to show a effect of obesity control as developing a herbal medicine, Gyeongshingangjeehwan16 (GGEx16), in order to control obesity that is a harmful factor for healthy. Method : In order to prove the effect of GGEx16, BMI, fat distribution, fat control and fitness score which are closely related with obesity are considered as variables. Each variable is measured, for statistical analysis, using measurement implement of InBody 3.0 which applied a theory of bioimpedence analysis. Result and Conclusion : As a result of statistical analysis for four variables, it was improved that there are the improved effect for obesity because GGEx16 is statistically meaningful better than prior to taking.

• 한국가시화정보학회:학술대회논문집
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• 2006.12a
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• pp.131-134
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• 2006

Whole flow fields of a room air conditioner (RAC) have been visualized by a Particle Image Velocimetry (PIV) technique to analyze the flow structure by various inlet and outlet angles, and to control an eccentric vortex which affects an efficiency and noise of the RAC. A test model with 5 stages of a cross flow fan has been manufactured and a transparent acryl has been installed at the side of the test model for the PIV experiment. The inlet and outlet flows and the flow inside the cross flow fan have been analyzed by varying the inlet grill angles and outlet blade angles. The movement of the eccentric vortex has been investigated experimentally by developing the measurement technique for the inner flow field of the cross flow fan, and the relationship between the control of the eccentric vortex and the inlet and outlet angles has been confirmed in this study.

• Journal of Preventive Medicine and Public Health
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• v.42 no.6
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• pp.343-348
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• 2009

The final decision of study design in molecular and genetic epidemiology is usually a compromise between the research study aims and a number of logistical and ethical barriers that may limit the feasibility of the study or the interpretation of results. Although biomarker measurements may improve exposure or disease assessments, it is necessary to address the possibility that biomarker measurement inserts additional sources of misclassification and confounding that may lead to inconsistencies across the research literature. Studies targeting multi-causal diseases and investigating gene-environment interactions must not only meet the needs of a traditional epidemiologic study but also the needs of the biomarker investigation. This paper is intended to highlight the major issues that need to be considered when developing an epidemiologic study utilizing biomarkers. These issues covers from molecular and genetic epidemiology (MGE) study designs including cross-sectional, cohort, case-control, clinical trials, nested case-control, and case-only studies to matching the study design to the MGE research goals. This review summarizes logistical barriers and the most common epidemiological study designs most relevant to MGE and describes the strengths and limitations of each approach in the context of common MGE research aims to meet specific MEG objectives.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.485-488
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• 2006

In order to investigate the possibility of waste mushroom logs as biomass resource chemical and physical characteristics of normal woods and waste mushroom logs such as crystallinity value, energy consumption, total sugar yield after hydrolysis chemical compounds and molecular weight distribution after acid hydrolysis, were examined. In the results, crystallinity of waste mushroom logs which were three year passed after the inoculation was decreased drastically from 49% to 33% during the cultivation. Lignin contents as chemical compounds of normal woods and waste mushroom logs were 21.07% and 18.78%, respectively. By the results of measurement of energy consumption, the size reduction of normal woods required a significantly higher energy than that of waste mushroom logs. In the hydrolysis, total sugar yield by enzyme and acid hydrolysis were high in waste mushroom logs(53% 57.5%) than in normal woods(42.9%, 47.17%). According to the molecular weight distribution using GPC, low molecular weight compounds were distributed in waste mushroom logs. Based on these results, waste mushroom logs have enough potential as material for developing alternative energy because of easily conversion to sugar by various hydrolysis methods and requirement of low energy consumption during size reduction.

• Fire Science and Engineering
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• v.18 no.2
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• pp.27-33
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• 2004

An accurate knowledge of the AIT(Autoignition temperatures) of chemicals is important in developing appropriate prevention and control measures in industrial fire protection. The AITs describe the minimum temperature to which a substance must be heated, without the application of a flame or spark, which will cause that substance to ignite. The measurement AITs are dependent upon many factors. namely initial temperature. pressure, volume, fuel/air stoichiometry. catalyst material, concentration of vapor, ignition delay time. This study measured the AITs of acids from ignition delay time by using ASTM E659-78 apparatus which was produced in the year 1994. The experiment AITs were a good agreement with the calculated AITs by the proposed equations with a few A.A.P.E.(average absolute percent error) and A.A.D.(average absolute deviation).

• Journal of Korea Society of Industrial Information Systems
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• v.5 no.3
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• pp.10-17
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• 2000

This paper focuses m the measurement of increased work efficiency and competitive advantage expected from the implementation of information systems through random interactions of the organizational behavioral factors whose attributes can be changed with. Specifically, the work reported here is concerned with modeling and analyzing the interrelationships among the organizational behavioral factors which a university information system can have impact on throughout the time horizon of its implementation in terms of productivity. In addition, it is also concerned with developing a continuous simulation model to be used to assess the impact of the information system.