• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.536-538
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• 2001

국내에서는 전력산업의 규제가 점차 완화되면서 전력시장은 새로운 틀이 형성되어지고 있다. 전력시장의 구조개편후 각 전력회사들은 그들의 판매수익을 높이기 위하여 행동하게 될 것이다. 즉 그들의 부하를 적절하게 조절함으로써 한계비용이 평균비용보다 낮게 유지되도록 하여 이윤극대화를 추구해 나갈 것이다. 따라서 전력회사들은 수요측의 관리가 과거 어느 때 보다 필요하게 될 것이며, 어떻게 하면 부하곡선의 피크치를 억제할 것인지 생각하게 된다. 이러한 것을 해결하기 위해 전력회사들은 그들의 소비자 대부분을 수요관리 프로그램에 참여시키 부하관리를 할 것이며 이를 통해 피크치 부하를 억제시켜 한계비용을 줄이려할 것이다. 소비자들을 수요관리 프로그램에 참여토록 유도하기 위하여 전력회사는 여러 가지 인센티브를 제공하게 되는데, 소비자들은 이러한 인센티브를 받아 프로그램에 참여할 것인지를 선택하게 된다. 본 논문에서는 전력회사가 수요관리 프로그램을 실행할 때 어떤 효과를 얻게 되고 참여자들이 느끼는 순이익은 어떻게 될지를 고려하게 될 것이다. 이러한 것들은 전력회사 입장에서는 수요관리 프로그램을 실행하는 것이 그들에게 이익을 가져다 줄 것인지를 말해주며 소비자들은 그들의 프로그램에 지속적으로 참여할 것인지를 선택하게 될 것이다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.7
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• pp.429-435
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• 2010

Although recently revised building code requires 15~20% increased thermal insulation performance for window systems, since the code is focusing on winter heat loss, it is not satisfactory to contribute on reducing rapidly rising cooling load in summer. Window systems have great impact on building heat gain and loss. Therefore technological development for window system specialized in shading solar gain in summer is an urgent matter. This study evaluates the performance of sun shading and thermal insulation for blind integrated window system. Also, computer simulation evaluates the effect of heating and cooling energy consumption reduction for an individual unit(floor area of $85m^2$) of a multi-family housing. Physibel Voltra, a heat transfer analysis software, was used to analyse the effect of energy consumption reduction, and the energy load was converted to the cost to compare the actual effect of economical benefit.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1649-1654
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• 2009

Induction motors widely use in industry because structure is simple and hard and cost is generally cheap and they are easy to control. In recently, because of saving steel, ventilation and benefit of frame fixing, rectangular core type induction motors use in industry more and more. This paper presents current characteristic according to stator core cutting degree in three-phase induction motor (IM) with rectangular stator core. According to stator cutting degree, magnetic saturation and paths of flux are changed. Because of these situations, phase currents are unbalance and are produced harmonic components and they cause decrease of efficiency. We analyze each $10^{\circ}$ from $0^{\circ}$ to $30^{\circ}$ using 2-D finite element analysis (FEA). Optimal stator cutting core degree selection supplies stable currents and efficiency improvement. In this paper, loss separation test was executed by IEEE Std. 112-98 Method B and we compare with the result of loss separation by Simulation using FEM and by Experiment.

• Korean Journal of Computational Design and Engineering
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• v.14 no.3
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• pp.186-196
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• 2009

Mass customization (MC) is a business practice that aims to provide customers with customized products and services at near mass production efficiency. To achieve the aim, a number of methods to implementing MC are proposed. However, most of them require changes in entire process of the company, which make companies hesitate to implement MC even if it is essential to survive. In this paper, we proposed alternatives to partially implement MC for quick adaptation of MC. The base line assumption is not to change the production lines. The pros and cons of alternatives are given by qualitative and quantitative evaluation. Especially, by giving radar chart analysis of the quantitative measures, we give insight on the changes in the business performance measures, such as time to market and cost. Proposed alternatives are based on sub-processes such as purchasing raw materials, production process changes and packaging for efficient logistics. In this way, companies are able to provide customized products with small changing of the current manufacturing system. The process and benefit of the proposed strategy is verified by real world cases of a Korean health food company.

• Geomechanics and Engineering
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• v.12 no.2
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• pp.257-267
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• 2017

This paper presents laboratory investigation of stabilization of subgrade soil. One type of soil and three types of stabilizers i.e., hydrated lime, class F fly ash and polypropylene fibres are selected in the study. Atterberg limit, compaction, california bearing ratio (CBR), unconfined compressive strength and triaxial shear strength tests are conducted on unstabilized and stabilized soil for varying percentage of stabilizers to analyze the effect of stabilizers on the properties of soil. Vertical compressive strains at the top of unstabilized and stabilized subgrade soil were found out by elasto-plastic finite element analysis using commercial software ANSYS. Strategy for design of optimum pavement section was based on extension in service life (TBR) and reduction in layer thickness (LTR). Extension in service life of stabilized subgrade soil is 6.49, 4.37 and 3.26 times more due to lime, fly ash and fibre stabilization respectively. For a given service life of the pavement, there is considerable reduction in layer thicknesses due to stabilization. It helps in reduction in construction cost of pavement and saving in natural resources as well.

• Steel and Composite Structures
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• v.6 no.5
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• pp.367-386
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• 2006

This paper describes the results of a numerical investigation of the large deflection behaviour of steel beams under fire conditions, taking into consideration the effect of catenary action provided by the surrounding structures. The main focus is on the development, validation and application of a simplified calculation method that may be adopted in design calculations. Because no experimental result is available for validation of the simplified calculation method, the finite element program ABAQUS has been used to simulate the large deflection behaviour of a number of steel beams so as to provide alternative results for validation of the proposed method. Utilising catenary action has the potential of eliminating fire protection to all steel beams without causing structural failure in fire. However, practical application of catenary action will be restricted by concerns over large beam deflection causing integrity failure of the fire resistant compartment and additional cost of strengthening the connections and the surrounding structures to resist the catenary forces in the steel beams. This paper will provide a discussion on practical implications of utilising catenary action in steel beams as a means of eliminating fire protection. A number of examples will then be provided to illustrate the type of steel framed structure that could benefit the most from exploiting catenary action in fire resistant design.

• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.4
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• pp.193-202
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• 2005

Marine risk assessment considers events such as collision/grounding, sinking/capsize, fire/explosion and flooding, developing relationships between their causes and effects. In addition, risk assessment of previously sunken ships are also necessary since they continuously have possibility for further oil spill or can cause other marine accidents. The objective of this paper is to develop the risk assessment systems for sunken ships to prevent oil spill and further marine causalities in order to preserve safe and clean oceans around Korea peninsula. The risk assessment systems for sunken ships comprise of database management sub-system for sunken ships, qualitative risk assessment sub-system, quantitative risk assessment sub-system, and cost-benefit analysis subsystem.

• Journal of Korean Society of Water and Wastewater
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• v.31 no.3
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• pp.205-217
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• 2017

This paper tries to show the efficiency of water financing between central and local governments. From the year of 2017, the operation and maintenance costs for change water pipes has been provided by central government as block grants system(RDSA: Regional Development Special Account). Even though the water financing is responsible for local government, water drought and high production cost in poor area affects the quality of life nowadays. Then, fiscal transfer through block grant for water financing has been decided to invest regional SOC. The purpose of the paper sheds light on the function of the block grant for public provision by water financing. The firstly tried empirical results are based on the survey from local governments and ministry of environments. The point of the empirical analysis shows that the local governments does not have proper measurement for unexpected water leakage and termination until now. In a policy manner, the paper raises the issues about benefit principle for water users by the increase of tariffs. In order to do so, the paper investigates the relationship between the water provision and fiscal status of each local governments.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.431-431
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• 2017

도시화로 인한 홍수 피해 및 비점오염원 저감 방안의 해법으로 정부부처 및 지자체에서는 LID 시설의 설치를 권장하고 있다. 국토부 산하 GI&LID연구단 및 관계 부처의 노력으로 국내 LID 기술의 도입 및 연구 개발이 활발히 이루어지고 있으며 우리나라 환경에 맞는 LID 시공 기술력을 확보하는 중이다. 하지만 비점오염 및 홍수 저감의 대안으로서 LID 기술은 각광받고 있으나 LID설치 비용의 과대 인식과 실효성에 대한 불안감이 만연하여 시설 설치에 어려움을 겪고 있다. 본 연구에서는 도심지내 LID 기술을 적극적으로 도입하여 단지 조성중에 있는 송산그린시티 친환경시범마을을 대상으로 시설 설치 비용에 따른 비용 편익을 분석하였다. 시설 설치전 불투수면적에서의 물순환 관리능력과 설치 후 투수 및 저류 능력의 확대에 따른 물순환 관리능력을 비교하였고, 일정 수치 이상의 물순환 관리능력을 갖기 위해서 시설 설치에 필요한 비용을 분석하였다. 금번 연구에서 분석한 모델링 결과는 추후 준공될 친환경시범마을의 실제 관측치와 비교하여 연구 실효성에 대한 분석을 수행할 예정이다. 본 연구를 통해 LID 시설 설치시 비용-편익을 분석하고 이점을 제시하여 추후 있을 LID 시공 및 관련 연구에 도움이 되고자 한다.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.626-637
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• 2008

Although the amount of travel demand is a critical factor in a benefit-cost (B/C) analysis of railway investment, the travel demand changes especially for induced demand have not been considered. Therefore, the basic study of how to estimate travel demand changes after railway investment is worth investigating. This study reviews the methodologies for estimating diverted and induced demand generated after railway investment, and proposes appropriate approaches that will help railway planners to practically apply them in a case study. Further, the research stimulates the needs of consideration of the travel demand changes in the feasibility studies of railway planning.