• 대한산업공학회지
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• 제24권1호
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• pp.115-126
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• 1998

A GDHS(Geothermal District Heating System) is a heating system supplying a group of districts with heat extracted from geothermal sources. Due to various advantages of GDHS including the saving of fuel consumption as well as the reduction of air pollution, a world-wide trend is to replace central/individual heating systems with GDH systems. The basic point of this paper is that a crash program mentality leads to inappropriate decisions about policy issues in large-scale research and development like the development of GDHS, R&D funding should be viewed as a sequential decision, not a once-and-for-all choice. Hence we develop on economic feasibility assessment model based on a continuous sequential decision process for the Chejoo Island GDHS Project by modifying Roberts's model.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전력기술부문
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• pp.220-222
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• 2005

When a large-scale load or a new generator is connected to power systems, KPX assesses the effect of the connection on power systems to keep security and reliability standards. As the number of connection requests has been increased, KPX is spending much time for technical assessments of the requests. This paper developed an automatic assessment program to reduce analysis time and enhance simulation accuracy. The program is based on IPLAN and. can be applied to both load and generator network connection requests.

• Wind and Structures
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• 제20권4호
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• pp.565-578
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• 2015

A wind energy assessment is an integrated analysis of the potential of wind energy resources of a particular area. In this work, the wind energy potentials for Mauritius have been assessed using a Computational Fluid Dynamics (CFD) model. The approach employed in this work aims to enhance the assessment of wind energy potentials for the siting of large-scale wind farms in the island. Validation of the model is done by comparing simulated wind speed data to experimental ones measured at specific locations over the island. The local wind velocity resulting from the CFD simulations are used to compute the weighted-sum power density including annual directional inflow variations determined by wind roses. The model is used to generate contour maps of velocity and power, for Mauritius at a resolution of 500 m.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.47-52
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• 2000

Recently, it is very necessary the development of the manufacturing techniques for high strength concrete(HSC) for the large-scale size and good quality of civil structure. But, the manufacture and quality control of HSC of which shrinkage, heat of hydration and workability at construction filed are considered, is very difficult due to its low water-cement ratio and high quantity of unit cement content. In the present study, we tried to know and assess the influences of chemical and physical properties of cement on the material properties of HSC. We analyzed basic properties of 4 kinds of cement whose chemical and physical properties are different each other through various tests such as chemical analysis and mortal test. Also, we performed the assessment of the material properties of HSC for each dement by the test for the conditions of same mix design and similar compressive strength. From the results in the study, the assessment of the important quality factors of cement influencing the properties of HSC may be utilized to quality control of applied cement to manufacture the HSC of high quality.

• 한국유기농업학회지
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• 제21권3호
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• pp.305-319
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• 2013

In this study, it is intended that utilize the LCA (Life Cycle Assessment) method, to evaluate the environmental impact of wood pellet manufacturing facility. As mentioned above, wood pellet manufacturing facility of 20 has produced wood pellets as a raw material sawdust and wood in our country. In this study, in order to feature manufacturing process of wood pellets that resemble almost necessary to analyze evenly size and characteristics of various equipment whether these reasonable, the characteristics of the equipment may be different, the production of 20 places I surveyed the facility one central timber distribution center one large scale most of the equipment.

• 환경영향평가
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• 제5권2호
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• pp.49-57
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• 1996

On the basis of sustainable long-term water resources planning, the development of ground water resources should be interlocked with the surface water development In considering the intertemporal equity, overpumping of groundwater may diminish or eliminate the groundwater resources stock of post-generations. Regulatory landuse zoning for groundwater resources recharge area is indispensable measures to prevent groundwater pollution. Adequate treatment of polluted water from various sources such as municipal sewage, industrial wastewater, landfill site leachate, and abandoned boring wells, is also necessary for groundwater protection. To preserve groundwater resources as common property goods, groundwater use tax should be imposed upon the large scale groundwater use. Finally, the establishment of groundwater development license system is recommended to achieve the social optimal production and to avoid external diseconomy.

• Journal of Ship and Ocean Technology
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• 제11권1호
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• pp.25-35
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• 2007

This paper is concerned with the fatigue strength assessment of tendon porch found which is categorized as the special structural member in TLP. Large-scale tendon porch specimens have been designed and fabricated with API 2W Gr.50 steel recently produced by POSCO. Fatigue test has been carried out for three tendon porch specimens under various load level. Fatigue strength has been evaluated based on the nominal stress range and the results are compared with the fatigue design curve of DnV RP-C203. From the present experimental study, it has been found that the porch specimens satisfy the fatigue design rule although test was carried out under the positive stress ratio. It can be, therefore, said that the API 2W steel produced by POSCO possess sufficient fatigue strength.

• 대한안전경영과학회지
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• 제15권4호
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• pp.17-24
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• 2013

On this study, we extracted pending problem and controversial point from management of disaster such as terror for domestic massive performance and then, investigated countermeasure plan against disaster for massive performance through comparison and analysis between anti-disaster strategy of Korea and U.S. U.S are conducting security system actively for passenger of major facilities such as public institution. Nonetheless, In U.S that has the world's best security system, serious affair such as 911 terror and Boston marathon terror are continued to happen. When considering domestic situation that North Korea and South Korea are antagonistic to each other, it is judged when it is high time to prepare for threat of terrorism. Accordingly, On this study, through analyzing of latest terror attacks in U.S and disaster risk in the nation, we analyzed in detail countermeasure plan classified as legislation, operation of security system, instilling a sense. As the result of this analyzing, using by flow-chart, we suggested domestic optimized disaster management system for massive performance. Consequently, we propose to establish systematized disaster management system such as preliminary survey of disaster influence for massive performance.

• Structural Engineering and Mechanics
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• 제43권3호
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• pp.371-394
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• 2012

Accurate finite element (FE) models are needed in many applications of Civil Engineering such as health monitoring, damage detection, structural control, structural evaluation and assessment. Model accuracy depends on both the model structure (the form of the equations) and the model parameters (the coefficients of the equations), and can be generally improved through that process of experimental reconciliation known as model updating. However, modelling errors, including (i) errors in the model structure and (ii) errors in parameters excluded from adjustment, may bias the solution, leading to an updated model which replicates measurements but lacks physical meaning. In this paper, an application of ambient-vibration-based model updating to a large-scale benchmark prototype of a building structure is reported in which both types of error are met. The error in the model structure, originating from unmodelled secondary structural elements unexpectedly working as resonant appendages, is faced through a reduction of the experimental modal model. The error in the model parameters, due to the inevitable constraints imposed on parameters to avoid ill-conditioning and under-determinacy, is faced through a multi-model parameterization approach consisting in the generation and solution of a multitude of models, each characterized by a different set of updating parameters. Results show that modelling errors may significantly impair updating even in the case of seemingly simple systems and that multi-model reasoning, supported by physical insight, may effectively improve the accuracy and robustness of calibration.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 춘계 학술발표회
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• pp.17-22
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• 2009

Reliability analyses were performed to quantify the risk in axially loaded large-scale pile foundations in consideration of pile-soil interaction and uncertainties on various design variables. The finite difference method based on an equivalent soil spring model and a load transfer method and Monte Carlo simulation method are integrated in the framework of reliabilty analysis. The applicability and efficiency of the proposed method in the safety assessment of axially loaded pile-soil system was verified using a realistic example. Since the proposed method can explicitly consider uncertainties in various design variables, and quantify failure probability of a pile foundation, it can be used to estimate risk, to obtain basic informations for life cycle cost analysis, and to develop code requirements for a reliability-based design of pile foundations.