• The Transactions of the Korean Institute of Electrical Engineers A
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• v.52 no.9
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• pp.535-541
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• 2003

Demand Side Management (DSM) activities have been designed to encourage customers to modify their patterns of electricity consumption including the timing and level of electricity demand. The role of DSM has been more and more important in the point of social energy utilization on the limited resources. The objectives of DSM are generally related to load reductions and generation cost savings. This paper presents an approach to B/C analysis to evaluate the impact of DSM programs especially on the strategic conservation and the load management programs. The proposed approach embedding the existing B/C analyses is applicable to the new electricity market. Case studies show the B/C ratio and the avoided cost due to the impact of DSM programs.

• Korean Chemical Engineering Research
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• v.49 no.2
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• pp.244-249
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• 2011

In this study, performance and economic analysis of 500 MWe coal-fired power plant with $CO_{2}$ capture process was performed. For this purpose, chemical absorption method which is commercially available and most suitable for thermal power plant was studied and a criteria for technical and economic assessment of power plants suggested by IEA Greenhouse Gas R&D Programme was used. And we performed the sensitivity analysis focused on regeneration energy which exceed half of the total capture energy. Based on MEA(Monoethanoleamine) as a main chemical solvent and 3.31 GJ/ton$CO_{2}$ regeneration energy in the stripper, net power efficiency was reduced from 41.0% (no capture) to 31.6%(with capture) and the cost of $CO_{2}$ avoided was estimated 43.3 $/ton$CO_{2}$. And in case of 2.0 GJ/ton$CO_{2}$ regeneration energy, the cost of $CO_{2}$ avoided was calculated as 36.7 $/ton$CO_{2}$.

• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.365-370
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• 2012

In this study, Economic analysis of supercritical coal-fired power plant with $CO_2$ capture process was performed. For this purpose, chemical absorption method using amine solvent, which is commercially available and most suitable for existing thermal power plant, was studied. For the evaluation of the economic analysis of coal-fired power plant with post-combustion $CO_2$ capture process in Korea, energy penalty after $CO_2$ capture was calculated using the power equivalent factor suggested by Bolland et al. And the overnight cost of power plant (or cost of plant construction) and the operation cost reported by the IEA (International Energy Agency) were used. Based on chemical absorption method using a amine solvent and 3.31 GJ/$tonCO_2$ as a regeneration energy in the stripper, the net power efficiency was reduced from 41.0% (without $CO_2$ capture) to 31.6% (with $CO_2$ capture) and the levelized cost of electricity was increased from 45.5 USD/MWh (Reference case, without $CO_2$ capture) to 73.9 USD/MWh (With $CO_2$ capture) and the cost of $CO_2$ avoided was estimated as 41.3 USD/$tonCO_2$.

• Journal of the Korea Society of Computer and Information
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• v.23 no.3
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• pp.85-92
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• 2018

We consider a project scheduling problem in which the jobs can be compressed by using additional resource to meet the corresponding due dates, referred to as a time-cost tradeoff problem. The project consists of two independent subprojects of which precedence graph is a chain. The due dates of jobs constituting the project can be interpreted as the multiple assessments in the life of project. The penalty cost occurs from the tardiness of the job, while it may be avoided through the compression of some jobs which requires an additional cost. The objective is to find the amount of compression that minimizes the total tardy penalty and compression costs. Firstly, we show that the problem can be decomposed into several subproblems whose number is bounded by the polynomial function in n, where n is the total number of jobs. Then, we prove that the problem can be solved in polynomial time by developing the efficient approach to obtain an optimal schedule for each subproblem.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.2
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• pp.264-268
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• 2016

Recently, various energy efficiency optimization activities are ongoing globally by integrating conventional grids with ICT (Information and Communication Technology). In this sense, various smart grid projects, which power suppliers and consumers exchange useful informations bilaterally in real time, have been being carried out. The electric vehicle diffusion program is one of the projects and it has been spotlighted because it could resolve green gas problem, fuel economy and tightening environmental regulations. In this paper, the economics of V2G system which consists of electric vehicles and the charging infrastructure is evaluated comparing electric vehicles for V2G with common electric vehicles. Additional benefits of V2G are analyzed in the viewpoint of load leveling, frequency regulation and operation reserve. To find this benefit, electricity sales is modeled mathematically considering depth of discharge, maximum capacity reduction, etc. Benefit and cost analysis methods with the modeling are proposed to decide whether the introduction of V2G systems. Additionally, the methods will contribute to derive the future production and the unit cost of electric vehicle and battery and to get the technical and economic analysis.

• Journal of Construction Engineering and Project Management
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• v.10 no.1
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• pp.16-32
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• 2020

Cost and time control of projects is important in preventing project failure. However, achieving effective cost and time control in practice is often challenging. The challenges of project cost and time control in practice are investigated by carrying out a questionnaire survey on the top 150 construction contractors in the UK followed by in-depth semi-structured interviews of practitioners from 15 construction companies in the country. Quantitative analysis reveals that design change is the most important factor inhibiting the ability of UK contractors from effectively controlling both the cost and time of construction projects. Four of the top five factors inhibiting effective cost control are also the top factors inhibiting effective time control albeit in a different order. These top factors-design changes, inaccurate evaluation of project time/duration, risk and uncertainty, non-performance of subcontractors and nominated suppliers were also found to be endogenous factors to the project. Additionally, qualitative analysis of the interviews reveals 16 key challenges to prevent for effective project cost and time control in practice. These are classified into four categorised based on where they stem from as follows; from the organisation (1. Lack of integration of cost and time during project control, 2. lack of management buy-in, 3. complicated project control systems and processes, 4. lack of a project control training regime); from the construction management/project management approach (5. Lapses in integration of interfaces, 6. project control not being implemented from the early stages of a project, 7. inefficient utilisation and control of labour, 8. limited time devoted to planning how a project will be controlled at the outset); from the client; (9. Excessive authorisation gates, 10. use of adversarial and non-collaborative forms of contracts, 11. communication problems within client set-up, 12. obstructive client representatives) and; from the project team (13. Lack of detailed/complete design, 14. lack of trust among the project partners, 15. limited time devoted to project control on site, 16. non-factual reporting). The study posits that knowledge of these project control inhibiting factors and challenges is the first step at ensuring they are avoided and enable the implementation of a more effective project cost and time control process in practice.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.16
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• pp.59-81
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• 2001

There are two methods of quantifying the damages when the contract is avoided. One is 'concret' assessment, the other is 'abstract' assessment. The former looks to the actual cost incurred by the aggrieved party in concluding a contract for the substitute transaction, while the latter is based on the market price. The concrete method of assessment forms the starting point in the Civil Law systems. In the Common Law systems, it is likewise available. The aggrieved party is entitled to recover the difference between the cost of cover or (as the case may be) the proceeds of resale and the contract price. Both systems also recognize the abstract method of assessment. If the aggrieved party does not resell or cover, damages are equal to the difference between the price fixed by the contract and the market price. The CISG and the UNIDROIT Principles recognize expressly both concrete and abstract methods. Under the relevant articles, the aggrieved party can recover the damages assessed by one of the methods as well as any further damages such as loss of profit, incidental and consequential damages.

• Journal of Korean Society for Quality Management
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• v.24 no.3
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• pp.65-76
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• 1996

This paper is concerned with designing $\bar{X}$-control charts when an estimate error may be Inevitable. Estimate error offen can not be avoided in estimating or measuring the parameter values of the cost model for the control charts. The bounded interval is a common practice to compensate for inherent estimating error. We introduce the 'propagation of error technique to deal with the economic design of the $\bar{X}$-control charts with imprecise information on the cost model parameters. A numerical example is presented to show· its ability in the economic design of $\bar{X}$-control charts.

• Proceedings of the IEEK Conference
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• 2000.07a
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• pp.493-496
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• 2000

We study the problem of designing at minimum cost a two-connected network topology such that the shortest cycle to which each edge belongs does not exceed a given maximum number of hops. This problem is considered as part of network planning and arises in the design of backbone networks. We propose a genetic algorithm approach that uses a solution representation, in which the connectivity and ring constraints can be easily encoded. We also propose a crossover operator that ensures a generated solution is feasible. By doing so, the checking of constraints is avoided and no repair mechanism is required. We carry out experimental evaluations to investigate the solution representation issues and GA operators for the network design problem.

• Nuclear industry
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• v.37 no.8
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• pp.38-57
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• 2017

이 보고서는 2019년, 2022년, 그리고 2040년에 가동에 들어가는 신규 발전원들의 균등화 발전 비용과 균등화 회피 비용의 평균값이 얼마나 되는지를 보여주는 데 그 목적이 있다. 이 보고서에 나온 자료는 Annual Energy Outlook 2017(AEO2017)를 작성하는 데 이용된 National Energy Modeling System(NEMS)에 있는 것들이다. 세 가지의 시나리오 중에서 2022년 가동에 들어가는 경우에 대해서만 본문에서 다루었고, 나머지 2019년과 2040년 가동에 들어가는 경우에 대해서는 각각 부록 A와 B에서 다루었다. 계산은 NEMS의 전력시장 모듈(EMM)에 들어 있는 미국의 22개 지역에 건설되는 발전 설비들을 대상으로 하고 있다. 이 보고서는 그 22개 지역 발전 설비들의 평균 균등화 발전 비용, 설비 용량을 고려한 가중 평균 비용, 지역 간 비용 편차, 그리고 균등화 회피 비용과 균등화 발전 비용의 차이 등을 계산하여 제시하고 있다.