• 대한안전경영과학회지
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• 제12권2호
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• pp.147-152
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• 2010

Project implementation plan is a blueprint that confirms project performance activities and specifies required man-hour, period and resource imput ratio. Various figures, the results of implementation plan, are predicted through estimation, and because of superiority of objectivity and repeatability, numerical formula-based estimation model is often used overseas. COCOMO model is the representative estimation model whose theories and formulas are publicized and it predicts the total man-hour required for software system development. This model is publicized in "Software Engineering Economics" written by Professor Barry Boehm of the U.S., and is the most widely applied numerical formula-based estimation model. This study is conducted to provide a series of methods that are optimal for KTDS environment by choosing COCOMO II model among various types of COCOMO models. In establishing implementation plan, COCOMO II model alone is not sufficient, it is necessary to link with and apply standard WBS system and standard man-hour. In establishing specific implementation plan, phased standard WBS system in order of the first phase of all the activities implemented in the project, Activity, Task, and Role, and the man-hour put into this should be distributed according to standard ratio from COCOMO II model's total man-hour. This study provides explainations by establishing standard WBS system and linking with COCOMO II model.

• 자동차안전학회지
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• 제13권4호
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• pp.33-38
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• 2021

This paper presents a comparative study between the parameter-optimized Pacejka model and artificial neural network model for the tire force estimation. The two different approaches are investigated and compared in this study. First, offline optimization is conducted based on Pacejka Magic Formula model to determine the proper parameter set for the minimization of tire force error between the model and test data set. Second, deep neural network model is used to fit the model to the tire test data set. The actual tire forces are measured using MTS Flat-Track test platform and the measurements are used as the reference tire data set. The focus of this study is on the applicability of machine learning technique to tire force estimation. It is shown via the regression results that the deep neural network model is more effective in describing the tire force than the parameter-optimized Pacejka model.

• ETRI Journal
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• 제37권1호
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• pp.11-20
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• 2015

This paper deals with optimal power allocation for channel estimation of orthogonal frequency-division multiplexing uplinks in time-varying channels. In the existing literature, the estimation of time-varying channel response in an uplink environment can be accomplished by estimating the corresponding channel parameters. Accordingly, the optimal power allocation studied in the literature has been in terms of minimizing the mean square error of the channel estimation. However, the final goal for channel estimation is to enable the application of coherent detection, which usually means high spectral efficiency. Therefore, it is more meaningful to optimize the power allocation in terms of capacity. In this paper, we investigate capacity with imperfect channel estimation. By exploiting the derived capacity expression, an optimal power allocation strategy is developed. With this developed power allocation strategy, improved performance can be observed, as demonstrated by the numerical results.

• 한국국방경영분석학회지
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• 제15권2호
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• pp.160-169
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• 1989

This study is concerned with the loss rate calculation for evaluating the safety of aircraft series. The objective of this study is to provide the estimation method of safety for the determination of aircraft series, when the aircraft is directly purchased off-the-shelf or co-produced. Especially, in case the initial operation capabilities of alternative aircrafts are substantially different, this research proposes the modified cumulative average method which can effectively estimate the safety of aircraft.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.328-333
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• 2004

Railway is huge traffic system which is operated organically combining all the elements; vehicle, track, electric power, signal/communication, operation, etc. Safety level has ben improved steadily by learning lessons from past accident. But with rapid progress in high-speed, massive, high-frequency transit fresh idea of accident prevention is now in order. In quest of effective and efficient countermeasure, we aim to establish an adequate safety evaluation/management method. Our proposals are basic concept relating to safety analysis of fatal accidents, AHP of Saaty, Fuzzy AHP.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(I)
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• pp.192-198
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• 2003

Railway is huge traffic system which is operated organically combining all the elements; vehicle, track, electric power, signal/communication, operation, etc. Safety level has been improved steadily by learning lessons from past accident. But with rapid progress in high-speed, massive, high-frequency transit fresh idea of accident prevention is now in order. In quest of effective and efficient countermeasure, we aim to establish an adequate safety evaluation/management method. Our proposals are basic concept relating to safety analysis of fatal accidents, AHP of Saaty, Fuzzy AHP.

• 한국유기농업학회지
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• 제16권4호
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• pp.367-390
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• 2008

Consumer's concerns over beef safety are increasing according to resuming U.S. beef import. And a few beef producers have converted into organic beef recently. This organic beef must have taste, nutrition and safety that consumers demand for. Korean organic beef should be gone on sale at the shop under direct management of producer's organizations or the special shop for Environmentally friendly products. So they should win consumers' confidence for beef safety and transparency in producing and marketing process.

• 대한안전경영과학회지
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• 제14권3호
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• pp.127-134
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• 2012

Plant safety management that is enforcing introducing more than 95% in domestic manufacturing industry is using total plant efficiency by the evaluation index, and as a result, can see a lot of examples that plant productivity, economy and safety is increased. The efficient safety estimation for a business should analyze an accident data by considering every possible and potential factor. This study's purpose centers plant safety management activities that is management system for plant production and safety efficiency's maximization, plant evaluation system that plant safety management activities factor(reliability, maitainability, safety, service quality) that is enforcing in manufacturing industry can develop evaluation model that can evaluate qualitative activities by quantitative activities in process that maximize plant safety management wishes to do design.

• 한국안전학회지
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• 제32권2호
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• pp.52-58
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• 2017

One of the most important elements of the management of chemical accident is threat zone estimation of fires, explosions and toxic gas dispersion based on chemical releases. The threat zone estimation is going to be standard of emergency response for the first defender and base line data of off-site risk assesment (hereinafter referred to as "ORA") and risk management plan (hereinafter referred to as "RMP"). Generally, ALOHA form EPA(U.S.) and Kora(from KOREA MINISTRY OF ENVIRONMENT) has been used for the off-site consequence analysis in Korea. However it is hard to predict accurate consequences rapidly in case of emergency. Hydrochloric acid is a multipurpose raw material used in many industrial applications such as chemical, metal and food industries. It is usually treated in concentrations from 10 ~ 35 %, and release accident have occurred frequently. In this study, we have developed a simplified estimating method and equation to calculate threat zone easily in case of emergency due to release accident of hydrochloric acid.

• 한국안전학회지
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• 제25권1호
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• pp.93-101
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• 2010

As safety-related regulations for signaling systems are standardized to IEC 61508/62278/62425, and others at the international level, safety activities and its assessment are required to be performed. And also there is the need to develop technologies for safety improvement to secure safety signaling systems in terms of technologies for safety activities on each life-cycle. In this paper we have developed the safety activity processes and technologies each steps of proposed processes respectively for railway signaling systems. And the proposed process and technologies are applied to the safety activities for mock-up signaling systems.