• Journal of Electrical Engineering and Technology
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• v.3 no.3
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• pp.320-330
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• 2008

This paper presents an improved dynamic programming (IDP) approach to solve the economic power dispatch problem including transmission losses in power systems. A detailed mathematical derivation of recursive dynamic programming approach for the economic power dispatch problem with transmission losses is presented. The transmission losses are augmented with the objective function using price factor. The generalized expression for optimal scheduling of thermal generating units derived in this article can be implemented for the solution of the economic power dispatch problem of a large-scale system. Six-unit, fifteen-unit, and forty-unit sample systems with non-linear characteristics of the generator, such as ramp-rate limits and prohibited operating zones are considered to illustrate the effectiveness of the proposed method. The proposed method results have been compared with the results of genetic algorithm and particle swarm optimization methods reported in the literature. Test results show that the proposed IDP approach can obtain a higher quality solution with better performance.

• Earthquakes and Structures
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• v.13 no.3
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• pp.323-335
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• 2017

A simplified framework for the probabilistic estimation of economic losses induced by the structural vulnerability in single-story and single-bay precast industrial buildings is presented. The simplifications introduced in the framework are oriented to the definition of an expeditious procedure adoptable by government agencies and insurance companies for preliminary risk assessment. The economic losses are evaluated considering seismic hazard, structural response, damage resulting from the structural vulnerability and only structural-vulnerability-induced e]conomic losses, i.e., structural repair or reconstruction costs (stock and flow costs) and content losses induced by structural collapse. The uncertainties associated with each step are accounted for via Monte Carlo simulations. The estimation results in a probabilistic description of the seismic risk of portal-like industrial buildings, expressed in terms of economic losses for each occurrence (i.e., seismic event) that owners (i.e., insured) and stakeholders can use to make risk management decisions. The outcome may also be useful for the definition of the insurance premiums and the evaluation of the risks and costs for the owner corresponding to the insurance industrial costs. A prototype of a precast concrete industrial building located in Mirandola, Italy, hit by the 2012 Emilia earthquake, is used as an example of the application of the procedure.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.50 no.9
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• pp.424-430
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• 2001

A multi-level optimal power flow(OPF) algorithm has been evolved from a simple two stage optimal Power flow algorithm for constrained power economic dispatch control. In the proposed algorithm, we consider various constraints such as ower balance, generation capacity, transmission line capacity, transmission losses, security equality, and security inequality constraints. The proposed algorithm consists of four stages. At the first stage, we solve the aggregated problem that is the crude classical economic dispatch problem without considering transmission losses. An initial solution is obtained by the aggregation concept in which the solution satisfies the power balance equations and generation capacity constraints. Then, after load flow analysis, the transmission losses of an initial generation setting are matched by the slack bus generator that produces power with the cheapest cost. At the second stage we consider transmission losses. Formulation of the second stage becomes classical economic dispatch problem involving the transmission losses, which are distributed to all generators. Once a feasible solution is obtained from the second stage, transmission capacity and other violations are checked and corrected locally and quickly at the third stage. The fourth stage fine tunes the solution of the third stage to reach a real minimum. The proposed approach speeds up the two stage optimization method to an average gain of 2.99 for IEEE 30, 57, and 118 bus systems and EPRI Scenario systems A through D testings.

• Journal of Preventive Medicine and Public Health
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• v.22 no.4 s.28
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• pp.528-541
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• 1989

The purpose of this study was to identify and measure the economic costs and benefits due to smoking in Korea. Cigarette smoking is a major cause of morbidity and mortality. In addition to the health risks of smoking, there are important economic consequences. A complete assessment of the economics of smoking requires evaluation of various health, economic, and intangible parameters, including benefits as well as costs of both the production and consumption of tobacco. In this article we focus on costs resulting from the health effects of smoking (expenditures for medical care and the value of productive output lost to morbidity, and premature mortality among smokers), since economic benefits from tobacco industry is offset by expenditures for purchasing tobacco. Two distinct methodologies will be applied to measure the economic costs of smoking cigarette, the human capital and willingness-to-pay approaches. This article used the former method. In 1985, total economic losses due to smoking was estimated as 505.7 billion won, which was composed of morbidity losses 64.9 billion won mortality losses 429.1 billion won and indirect costs 11.7 billion won.

• Proceedings of the KIEE Conference
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• 1998.07c
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• pp.1111-1113
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• 1998

A robust economic dispatch algorithm involving transmission losses is proposed and investigated for a possibility of on-line applications. In this paper, the penalty factors are calculated directly from transposed Jacobian of load flow analysis with advantages of superiority to B-coefficients method based on its computation time and suitability for real time application since the approach is based on a current system condition. The proposed algorithm is systematically handling the generation capacity constraints with transmission losses. Implementation of the algorithm for IEEE systems and EPRI Scenario systems shows that computation time is enough to apply on-line economic dispatch to large power system and production cost is saved compared with the crude classical economic dispatch algorithm without considering transmission losses.

• Proceedings of the KIEE Conference
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• 1998.07c
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• pp.926-928
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• 1998

A fast optimization algorithm has been evolved from a simple two stage optimal power flow(OPF) algorithm for constrained power economic dispatch. In the proposed algorithm, we consider various constraints such as power balance, generation capacity, transmission line capacity, transmission losses, security equality, and security inequality constraints. The proposed algorithm consists of four stages. At the first stage, we solve the aggregated problem that is the crude classical economic dispatch problem without considering transmission losses. An initial solution is obtained by the aggregation concept in which the solution satisfies the power balance equations and generation capacity constraints. Then, after load flow analysis, the transmission losses of an initial generation setting are matched by the slack bus generator that produces power with the cheapest cost. At the second stage we consider transmission losses. Formulation of the second stage becomes classical economic dispatch problem involving the transmission losses, which are distributed to all generators. Once a feasible solution is obtained from the second stage, transmission capacity and other violations are checked and corrected locally and quickly at the third stage. The fourth stage fine tunes the solution of the third stage to reach a real minimum. The proposed approach speeds up the coupled LP based OPF method to an average gain of 53.13 for IEEE 30, 57, and 118 bus systems and EPRI Scenario systems A through D testings.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.341-343
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• 2000

Traditionally electric power system are operated in such a way that the total fuel cost is minimized regardless of accounting for tie-lines transmission constraint and emissions produced. But tie-lines transmission and emissions constraint are very important issues in the operation and planning of electric power system. This paper presents the Two-Phase Neural Network(TPNN) to solve the Economic Load Dispatch (ELD) problem with tie-lines transmission and emissions constraint considering transmission losses. The transmission losses are obtained from the B-coefficient which approximate the system losses as s quadratic function of the real power generation. By applying the proposed algorithm to the test system, the usefulness of this algorithm is verified.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.192-194
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• 2015

The growing size and complex process in construction project recently leads to increase risk and the losses as well. Even though researchers have identified the major risk indicators, there is lack of comprehensive and quantitative research for identifying the relationship between the risk indicators and economic losses associated with construction projects. To address this shortage of research, this study defines risk indicators and create a framework to assess the influence of economic losses from the indicators. An insurance company's claim payout record was accepted as the dependent variable to reflect the real economic losses. Based on the claims, we categorized the causes and results of accidents. To establish framework, built environment vulnerability indicators and geographical vulnerability indicators were employed as the risk indicators. A Pearson correlation analysis was adopted to validate the relationship with loss ratio and risk indicators. Consequently, this framework and its results may offer significant references for under writers of insurance companies and loss prevention activities.

• International Journal of Advanced Culture Technology
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• v.10 no.3
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• pp.25-32
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• 2022

This study analyzes the impact of occupational accidents on economic growth and labor productivty losses in Korea between January 2008 and July 2018, using the Vector Error-Correction Model (VECM). According to the analysis, the occurrence of occupational accidents was revealed to reduce the number of employed workers and also hinder economic growth. This can be reinterpreted as the reduction of occupational accidents does not cause labor losses in the industry, rather may induce economic growth. Also, the findings discovered that an increase in the number of workers may lead to increase in the probability of occupational accidents in the short term. This suggests that greater number of work-related accidents may occur during the early stages- due to new employees' lack of knowledge related to safety at workplace.

• IE interfaces
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• v.21 no.4
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• pp.365-377
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• 2008

In this paper, for constructing the Korean Hazard Information System (KHIS), we conceptually design a hazard evaluation process. We first deal with a hazard evaluation process focused on flood hazard to give the most immense damage and loss. The hazard evaluation process is consist of a damage evaluation process and a loss evaluation process, and is used for transforming hazards from natural disasters into economic measures. The proposed process is developed based on the famous FEMA (Federal Emergency Management Agency)'s $HAZAS^{@MH}$methodology. We modify the FEMA's process to be mutually exclusive and collectively exhaustive, that is all losses from the hazards are included into the estimation process but the losses are not duplicated in the process. In addition to this, we define the loss process specifically by considering the characteristics from the hazard environments of Korea. We can expect that KHIS for evaluating economic losses from natural hazards can be developed based on the conceptual design for the economic loss evaluation process, and KHIS can be used as a useful tool for analyzing the feasibilities of mitigation plans in central/local governments.