• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.9
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• pp.657-662
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• 2012

The cogeneration system can operate at efficiencies greater than those achieved when heat and power are produced in separate. The optimal system can be determined by selecting the auxiliary system combined with cogeneration system. In the present study, economic investigation has been conducted with the cogeneration electric heat pump(EHP) system and the cogeneration absorption chiller(AC) system to install in a school dormitory. To analyze life cycle cost(LCC), cost items such as initial investment costs, annual energy costs and maintenance costs of each system have been considered. The initial investment cost is referred to the basis of estimated costs, and annual energy costs such as the electric power and gas consumption are based on the data in a school dormitory. LCC is evaluated with the present worth method. Considering investigated results, the initial investment cost of the cogeneration EHP system is more profitable about 24% than that of the cogeneration AC system. The energy cost of the cogeneration EHP system is more profitable about 8% than the cogeneration AC system. The LCC shows that the cogeneration EHP system is the most effective system in the school dormitory.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.03b
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• pp.273-280
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• 2000

In recent years there has been a steady increase in geoenvironmental engineering projects where geotechnical engineering has been combined with environmental concerns. Many of these projects involve some investigation of contaminant in the ground. There are many techniques such as geophysical, drilling, sampling, md pushing techniques for investigation of contaminated ground. The most rapidly developing site characterization techniques for geoenvironmental purposes involve direct push technology, that is, penetration tests. The purpose of this study investigated underground oil storage tanks(USTs) using the envi-cone penetrometer system. The electrical resistivity sensor, pH sensor, ORP sensor, and thermometer are installed in envi-cone penetrometer system. This envi-cone penetrometer system provides a continuous profile of measurements, and it is rapid, repeatable, reliable and cost effective for investigation of contaminated ground surrounding the underground oil storage tanks.

• 한국정보통신설비학회:학술대회논문집
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• 2003.08a
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• pp.373-375
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• 2003

통신사업자들은 다양한 정보서비스를 제공하기 위한 노력과 통신품질 향상을 위한 시도를 다양하게 진행하고 있으며, 우수한 품질의 서비스를 저렴하게 공급하기 위한 노력도 시도하고 있다. 본 고에서는 KT가 경영 합리화와 내부 원가절감을 위한 여러 가지 노력 중에서 투자시설 공사와 관련하여 공사원가 계산방법의 개선을 위해 새로 도입한 다양한 방법들을 살펴본다. 특히 교환시설분야에서 적용 중인 실적공사비에 의한 예정가격 산정방법을 중심으로 개념과 적용사례 분석을 하기로 한다.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.1241-1244
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• 2005

In this case study, the field investigation work on soft soils like a reclamation area with dredged-clay or intertidal mud flat which has not enough strength to resist the load of surveying machines, the amphibious barge(modified AMFIROL) which travels on land and water was adopted to the field investigation work. Despite of slight increase of cost, it was found that the adoption of amphibious barge in field investigation could improve the quality of test results and avoid the waste of time and some effort.

• International Journal of Railway
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• v.6 no.2
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• pp.45-52
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• 2013

Railway construction needs vast soil investigation for its infrastructure foundation designs along the planned railway path to identify the design parameters for stability and serviceability checks. The soil investigation data are usually classified and grouped to decide design input parameters per each construction section and budget estimates. Deterministic design method which most civil engineer and practitioner are familiar with has a clear limitation in construction/maintenance budget control, and occasionally produced overdesigned or unsafe design problems. Instead of using a batch type analysis with predetermined input parameters, data population collected from site soil investigation and design load condition can be statistically estimated for the mean and variance to present the feature of data distribution and optimized with a best fitting probability function. Probabilistic approach using entire feature of design input data enables to predict the worst, best and most probable cases based on identified ranges of soil and load data, which will help railway designer select construction method to save the time and cost. This paper introduces two Monte Carlo simulations actually applied on estimation of retaining wall external stability and long term settlement of organic soil in soil investigation area for a recent high speed railway project.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2004.04a
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• pp.67-70
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• 2004

The purpose of this study is to develop the investigation technology of ground characteristics and environments using eco cone penetration system. The underground environments of landfill was investigated and analyzed by this eco cone system. The electrical resistivity sensor, pH sensor, ORP sensor, and thermometer are installed in eco cone penetration system. This eco cone penetration system provides a continuous profile of measurements in underground, and provides repeatable, reliable and cost effective results for investigation of clean and contaminated ground.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.05a
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• pp.33-36
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• 2000

The purpose of this study investigated underground oil storage(USTs) and Landfill using the envi-cone penetrometer system. The electrical resistivity sensor, pH sensor, ORP sensor, and thermometer are installed in envi-cone penetrometer system. This envi-cone penetrometer system provides a continuous profile of measurements, and it is rapid, repeatable, reliable and cost effective for investigation of contaminated ground.

• International Journal of Highway Engineering
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• v.19 no.5
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• pp.153-162
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• 2017

PURPOSES : This study was conducted to analyze the effects arising from extending the duration of nighttime road construction on improving road quality and durability. METHODS : Most previous studies estimating the social cost of various construction conditions did not consider road pavement cooling time as a factor in improving road pavement quality. This study investigated the feasibility of achieving higher road quality and durability by extending the duration of nighttime road construction time extension. For this investigation, the effects of such an extension on traffic conditions were analyzed based on micro-simulation studies and scenario-based cost-benefit analyses, using factors including traffic volume, delay, construction cost, and road pavement cooling time. RESULTS : The results of the traffic simulation studies and cost-benefit analyses indicate that the current road construction method that emphasizes completing nighttime road construction by 6 a.m. reduces pavement life while causing relatively little traffic delay. If the night construction time is instead extended to 2 p.m., road pavement lifetime is increased, reducing road re-construction cost. These savings are greater than the cost of congestion arising from extending the duration of nighttime construction. CONCLUSIONS : The current nighttime construction durations need to be extended in order to efficiently manage roads and reduce road management costs.

• Journal of Korean Society for Quality Management
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• v.26 no.4
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• pp.219-238
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• 1998

The objective of this study was to establish a procedure of concurrent engineering which can be easily a, pp.icable in Korean industry. An investigation of various techniques of concurrent engineering was conducted. Problems of Korean companies which can be resolved by concurrent engineering techniques were identified. Techniques which can resolve these problems at the relatively low cost and without complicated computer facilities were selected and form a procedure for this study. The procedure was a, pp.ied to a manufacturing company for validation. It was found that this procedure can substantially reduce time and cost of R&D and manufacturing.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.138-139
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• 2015

Human productivity of Boring Machine for stack is provided but not its hourly workable quantity(Q-value) in the Equipment ownership cost and expenses section of the Poom-Same that is used for construction cost estimation of public sectors in Korea, which leads to less realistic and subjective estimation for the works. The optimized Q-value of the machine is proposed as a result of thorough investigation into many of its operations.