• KIEAE Journal
• /
• 제5권3호
• /
• pp.25-31
• /
• 2005

Computer simulations were performed for Heating Ventilating and Air-Conditioning (HVAC) systems to figure out more efficient maintenance methods for the building used for adolescent trainees. This study aims at suggesting design alternatives for optimum operation and performing life cycle cost (LCC) for each alternative. First, the capacity of the heat source equipment was determined using annual maximum heating and cooling loads. Annual loads were calculated and applied to the alternative for the purpose of calculating annual energy cost. Second, several types of data were collected to predict energy cost. Finally, the pay back period for each alternative was calculated using total cost estimation during standard duration period. This study indicates that the absorption chiller that does not occupy most part of a mechanical room, and does not need much operation cost was most economical.

• 한국전산구조공학회:학술대회논문집
• /
• 한국전산구조공학회 2008년도 정기 학술대회
• /
• pp.387-390
• /
• 2008

The importance of the life cycle cost analysis for construction projects of bridge has been recognized over the last decades. Accordingly, theoretical models, guidelines, and supporting softwares have been developed for the life cycle cost analysis of bridges. However, it is difficult to predict life cycle cost considering uncertainties precisely. This paper presents methodology for optimal design of substructure for a steel box bridge. Total life cycle cost for the service life is calculated as sum of initial cost, damage cost considering uncertainty, maintenance cost, repair and rehabilitation cost. The optimization method is applied to design of a bridge substructure with minimal cost, in which the objective function is set to life cycle cost and constraints are formulated on the basis of Korean Bridge Design Specification. Initial cost is calculated based on standard costs of the Korea Construction Price Index and damage cost on the damage probabilities to consider the uncertainty of load and resistance. An advanced first-order second moment method is used as a practical tool for reliability analysis using damage probability. Maintenance cost and cycle is determined by a stochastic method and user cost includes traffic operation costs and time delay costs.

• 대한토목학회논문집
• /
• 제29권5D호
• /
• pp.627-634
• /
• 2009

최근 국내에서 많이 시행되고 있는 BTL(Build Transfer Lease)사업은 수익성이 낮은 문화, 교육, 복지부문의 사회기반시설을 조기에 확충함으로써 국민들의 삶의 질을 높여주는 역할을 한다. 그러나 현재까지 BTL사업의 공사비는 초기공사비에 중점을 두고 있으며, 상대적으로 운영비 산정에 대한 합리적 기준이 정해져 있지 않아 비효율적인 낮은 운영비 관리체계가 되고 있다. 저가 운영비는 사업완공 후 시설 운영시 서비스의 질을 저하할 수 있고, 사업의 성과에도 큰 영향을 미친다. 따라서 본 연구에서는 기존 하수처리시설의 운영부문에 대한 실적자료를 이용하여 사업계획 초기에 운영비와 운영인력을 산정하는 방안을 제시한다. 이러한 연구는 향후 BTL사업으로 시행되는 하수처리시설의 계획시 시설 규모에 따른 개략적인 운영비 산정에 활용성을 갖을 것으로 기대되며, 타 시설물의 BTL사업 운영비 산정체계 구축시 참고 자료가 될 수 있다.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2004년도 ICCAS
• /
• pp.363-366
• /
• 2004

KAERI is developing the Advanced Spent Fuel Conditioning Process (ACP) as a pre-disposal treatment process for spent fuel. In this process, the management process must operate in intense radiation fields as well as in a high temperature. Therefore, remote maintenance has played a significant role in this process. Hence suitable remote handling and maintenance technology needs to be developed along with the design of the process concepts. To do this, we developed the digital mockup for the ACP. The digital mockup provides the capability of verifying the remote operability of the process without fabrication of the process equipment. In other words, by applying virtual reality to the remote maintenance operation, a remote operation task can be simulated in the digital mockup. Through utilizing this graphic simulation in this digital mockup, general guidelines can be established for designing equipment intended for remote handling and maintenance. Also, the designer of the equipment that must be remotely maintained should ensure that there is adequate access to the process equipment. The graphic simulator will substantially reduce the cost of the develo363pment of the remote handling and maintenance procedure as well as the process equipment.

• 한국통계학회:학술대회논문집
• /
• 한국통계학회 2002년도 추계 학술발표회 논문집
• /
• pp.147-151
• /
• 2002

Burn-in is a widely used method to eliminate initial failures. Preventive maintenance policy such as block replacement with minimal repair at failure is often used in field operation. In this paper burn-in and maintenance policy are taken into consideration at the same time. The cost of a minimal repair is assumed to be a non-decreasing function of its age. The problems of determining optimal burn-in times and optimal maintenance policy are considered.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
• /
• pp.855-858
• /
• 1988

Two methods for probabilistic maintenance scheduling are developed and compared ; one with operation and supplied-shortage cost and other with risk level of LOLP. Based on the real economic power dispatch, quadratic optimal maintenance conditions are obtained and simple amtrix equations are suggested for solutions. Both methods are compared in a sample system of 26,000 [MW] peak and 32,000 [MW] generation capacity.

• 한국인공지능학회지
• /
• 제6권1호
• /
• pp.1-10
• /
• 2018

Compressed Air is an important energy source used in most factories nowadays. The automation trend using air compressor has been gradually increasing with the interest of the 4th industry in recent years. With the air compressor system, it is possible to construct the device at low cost and easily achieve automation and energy saving. In addition, With trend of FA, miniaturation and light weight manufacturing trend expand their use in the electronics, medical, and food sectors. Research method is to design the technology for the remote control of the following information as USN base. Development of flexible sensing module from real time observation module for fusion of IT technology in compressed air systems, design and manufacture of flexible sensing module, and realiability assessment. Design of real-time integrated management system for observation data of compressed air system - Ability to process observation data measured in real time into pre-processing and analysis data. This study expects unconventionally decreasing effect of energy cost that takes up 60~70% of air compressor layout and operation and maintenance management cost through USN(Ubiquitous Sensor Network) technology by using optimum operational condition from real time observation module. In addition, by preventing maintenance cost from malfunction of air compressor beforehand, maintenance cost is anticipated to cut back.

• 한국IT서비스학회지
• /
• 제18권4호
• /
• pp.67-82
• /
• 2019

The purpose of this study is to improve the calculation method of the software operation pricing proposed by the software business price calculation guide from 'input manpower method' to 'rate calculation method'. The software operation pricing of the input manpower method is not objectively calculated in the domestic IT outsourcing situation where the statistical data based on the activity based estimating is insufficient and it is decided by agreement between the owner and the client. In addition, there was no standard for adjusting the productivity according to the characteristics of the operation service. In order to improve this, an operational correction factor item that can affect the software operation productivity was selected based on foreign and domestic standards, and it was confirmed through the first questionnaire to IT operation managers. In order to determine the level of difficulty of the fixed operational correction factors, the operational correction factor using AHP technique was confirmed through a second questionnaire for pairwise comparison. The operational difficulty calculation table was developed with reference to COCOMO and ITIL standards. Finally, we propose a new pricing scheme that reflects the operating rate. Regression analysis was carried out by collecting the data of the domestic public institutions on the estimated cost and the actual cost calculated from the new rate method software operation pricing. The results of the regression analysis show that the estimated cost and the actual cost are related to each other. Mean magnitude of relative error(MMRE) and PRED[25] analysis were added for accuracy analysis. MMRE and PRED also showed satisfactory results, confirming the possibility of replacing the rate method software operation pricing.

• 대한전기학회논문지
• /
• 제37권6호
• /
• pp.339-349
• /
• 1988

The simplified simulation technique for the best generation mix is developed and the studied results are described. The best generation mix over study time from the economic point of view can be easily constructed by this technique. Generator maintenance, the operation of pumpgenerator and LNG thermal generator with limited energy are simulated variously, so a role of each generator is also easily evaluated. Through parametric analysis, useful planning guide points are obtained for the best generation mix transition, nuclear power plant construction cost, ruanium cost , oil cost, coal cost and midnight factor in the study case corresponding to real power system size model.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2009년도 춘계학술대회 논문집
• /
• pp.643-652
• /
• 2009

This paper presents brief history and a state-of-the-art survey of Life Cycle Cost (LCC) analysis, in particular LCC analysis in the Urban Transit Vehicle, based on a internationl codes and standards related to LCC analysis. A main objective of the LCC analysis is to quantify the total cost of ownership of a product throughout its full life cycle, which includes research and development, construction, operation and maintenance, and disposal. The predicted LCC is useful information for decision making in purchasing a product, in optimizing design, in scheduling maintenance, or in planning overhaul. This paper presents a LCC procedure consisting of seven steps, which are "Problems definition", "Cost elements definition", "System modeling", "Data collection", "Cost profile development", "Evaluation", and "Verification". Sub-activities to be encompassed in the seven steps procedure are described.