• Water for future
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• v.26 no.2
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• pp.89-97
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• 1993

For the system benefit optimization by considering risk or reliability from a multiple reservoir system using the Monte Carlo technique, many stochastically generated inflow series have to be used for the system analysis. In this study, the stochastically generated inflow series for the multiple reservoir system operation are preprocessed according to the considered system objectives and operating time periods. Through this procedure, several representative inflow series which have discrete probability levels and operation horizons are selected among the thousands of generated inflows. Then a deterministic optimization technique is applied to the power energy estimation from the Han River Reservoirs System which considers five reservoirs in the study. It took much lower computational requirements then using the original Monte Carlo Technique, even though estimated result was almost similar.

• Environmental Analysis Health and Toxicology
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• v.30 no.sup
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• pp.5.1-5.5
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• 2015

Objectives To protect public health from risk, the Minister of Environment in Korea legislated an act concerning the registration and evaluation of chemical substances. In this study, we estimated the value of a statistical life (VSL) of carcinogenic chemicals to evaluate the socioeconomic analysis in Korea. Methods The estimation of the health benefit can be calculated through an individual's VSL and willingness to pay (WTP). To estimate the VSL and WTP, we used a contingent valuation method through a web-based survey. Results The survey is conducted with 1434 people living in Seoul and six large cities. An analysis of the survey is essential to review the distribution of the characteristics of the target population. The statistically significant variables affecting the WTP are location, age, household income, quality of life. Through the review of data, we secured statistical validity. The WTP was estimated as 41205 Korean won (KRW)/person, and the estimated VSL appeared as 796 million KRW/person. Conclusions There is a case in which the amount of statistical life value is estimated in connection with domestic environmental policy, fine dust, etc. However, there are no cases of evaluation for chemical. The utilization of this result is possible for conducting other study with chemicals.

• KCID journal
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• v.17 no.2
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• pp.3-16
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• 2010

The subject of externality of agricultural water supply has been discussed in the OECD AC ( Organization for Economic Cooperation and Development Agriculture Committee) while argued between monsoon Asian developing countries and the agricultural product export nations (Australia, EU, etc). It argued that a 'positive' approach to multifunctionality views agriculture as an economic activity with multiple, interconnected outputs or effects, and a 'normative' approach interprets multifunctionality in terms of the multiple roles assigned to agriculture. and the agricultural product export nations insisted 'negative' approach to externality of agricultural water supply like causing water pollution. So, in this study, define the externalities (positive, negative and economic, environmental) in terms of the agricultural water supply and calculate benefit and cost each the externalities by cost estimation. As results, BC is calculated to 1.28 which means that it is more economical to agricultural water supply and shows that although the negative exernalities comes out while supply the agricultural water, it still more valuable to supply the agricultural water.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.3
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• pp.469-474
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• 2009

An RFID system consists of radio frequency tags attached to objects that need to be identified and one or more electromagnetic readers. Unlike the traditional bar code system, the great benefit of RFID technology is that it allows information to be read without requiring contact between the tag and the reader. For this contact-less feature, RFID technology in the near future will become an attractive alternative to bar code in many application fields. In almost all the 13.56MHz RFID systems, FSA algorithm is used for identifying multiple tags in the reader's identification range. In FSA algorithm, the tag identification time and system efficiency depend mainly on the number of tags and frame size. In this paper, we propose a tag number estimation scheme and a dynamic frame size allocation scheme based on the estimated number of tags.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.1B
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• pp.46-55
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• 2006

It is only natural, given that the competition environment and policy priorities in the telecommunications market vary from one country to another, that methods for assessing the cost of universal service obligations differ as well. In Korea, with the introduction in 2004 of LRIC for assessing the universal service cost, the national telecommunications authority is preparing for a substantial revision of the current cost assessment method, and discussions on details of changes to be introduced are in full swing. This paper will study estimation methods for universal service costs adopted by countries around the world and compare practices concerning two of the major issues surrounding the assessment of universal service obligation cost - universal service cost ceiling and intangible benefits - to provide directions for changes to be introduced to Korea's own cost estimation model.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.371-375
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• 2007

Due to the benefit of QRA(Quantitative Risk Analysis) method, we can evaluate the risk, and it helps us to make our safe. We also depend to some of correlation equations to assess the jet fire at high pressurized transmission line. However, we can evaluate the risk within limitations. After comparing the current model to investigation report of natural gas transmission line accident at EL-Paso in U.S., this study concludes that more research and study are required because currently developed model cannot expect factors of the fire risk such as flame configuration.

• Journal of Ship and Ocean Technology
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• v.4 no.4
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• pp.19-33
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• 2000

For the prevention of marine accidents based on human factor, the risk assessment analysis procedure is proposed which consists of (1) the structural analysis of marine accident, (2) the estimation of incidence probability based on the Fault Tree analysis, (3) the prediction of ef-fectiveness to reduced the accident risk by suitable countermeasures in the specified functional system, and (4) the risk assessment by means of minimizing of the total cost expectation and the background risk. As a practical example, the risk assessment analysis for preventing is investigated using the proposed method.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.157.5-157
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• 2001

Generally, the application of Programmable Logic Controller PLC is emphasized on the Process Control. This paper presents Neurofuzzy application, Which can estimate the distance to a fault by means of PLC and based up on the Electrical Power System theory and ground resistance. The case study refers to the distribution lines of the Provincial Electricity Authority (PEA). Also, the thesis is supposed to be of much benefit: saving time both to go to the scene and to clear fault, reducing unpleasant impacts on customers and stabilizing reliability of the distribution lines.

• 제어로봇시스템학회:학술대회논문집
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• 1999.10a
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• pp.125-128
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• 1999

A linear time-invariant model can be described either by a parametric model or by a nonparametric model. Nonparametric models, for which a priori information is not necessary, are basically the response of the dynamic system such as impulse response model and frequency models. Parametric models, such as transfer function models, can be easily described by a small number of parameters. In this paper aiming to take benefit from both types of models, we will use linear-combination of basis fuctions in an impulse response using a few parameters. We will expand and generalize the Kautz functions as basis functions for dynamical system representations and we will consider estimation problem of transfer functions using Kautz function. And so we will present the influences of poles settings of Kautz function on the identification accuracy.

• Communications for Statistical Applications and Methods
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• v.20 no.4
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• pp.321-327
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• 2013

Bayesian and empirical Bayesian methods have become quite popular in the theory and practice of statistics. However, the objective is to often produce an ensemble of parameter estimates as well as to produce the histogram of the estimates. For example, in insurance pricing, the accurate point estimates of risk for each group is necessary and also proper dispersion estimation should be considered. Well-known Bayes estimates (which is the posterior means under quadratic loss) are underdispersed as an estimate of the histogram of parameters. The adjustment of Bayes estimates to correct this problem is known as constrained Bayes estimators, which are matching the first two empirical moments. In this paper, we propose a way to apply the constrained Bayes estimators in insurance pricing, which is required to estimate accurately both location and dispersion. Also, the benefit of the constrained Bayes estimates will be discussed by analyzing real insurance accident data.