• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.7
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• pp.392-397
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• 2013

To fulfill the demands concerning energy efficiency for zero energy buildings, various technologies of architects and engineers are required. This study aims to estimate the thermal performance of heat source equipment in which part load characteristics are considered in an office building. Overestimation of heat source equipment was reviewed through literature survey, and heating and cooling loads depending on the capacity and division of the equipment were analyzed through a simulation program (DOE-2.1E). The conclusions gained from this study are as follows; 1) The more the division of equipment, the less the heating and cooling energy consumption. 2) When a large item of equipment is divided into two small items of equipment, the optimum application rate showed as 5:5 for chiller, and 7:3 for boiler, respectively.

• Journal of Energy Engineering
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• v.22 no.3
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• pp.283-286
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• 2013

The existing nuclear power plants have been often redesigned by increasing or decreasing electrical power without changing design concept by the request of utility, economic factors or other factors. When the cost of power plant equipment redesigned by changing reactor power and electrical power is estimated, if its quotation is not available in the market place, cost scaling factor(CSF) applies to the cost of existing plant equipment and then the new-designed equipment cost can be calculated. In this paper, we review CSFs according to plant capacity change cases in United State DOE, EPRI, ABB, SWEC and introduce the results applied to Korean PWR 1000MWe and 1400MWe.

• KIEAE Journal
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• v.14 no.6
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• pp.105-110
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• 2014

The basic factors determining the amount of energy used in hospital buildings are weather conditions and building factors. But the real energy consumer is central plant equipment such as boilers and chillers that produce thermal energy for heating and cooling. Inaccurate decision of the primary equipment's size can cause a high initial-cost, an excessive equipment space, a wasted energy by low operation-efficiency and shortening of the machine's life. In this reason, the decision of optimal size for central plant equipment is very important. There are several factors for the decision such as an operation factor, a factor (equipment factor), piping losses and a simultaneous usage factor applied in the sizing process except a basic cooling load. But there is no standard method for applying those factors. Usually, factors are applied individually by an experience or custom of each engineer. In this study, the authors emphasize the meaning and the problem of those factors, examine them by analyzing factors which were applied to actual practices, and propose the recommendation value of safety, load, operation factors and application methods.

• Fire Science and Engineering
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• v.32 no.1
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• pp.57-65
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• 2018

In this study, a post-fire safe shutdown analysis (PFSSA) including multiple spurious operation (MSO) treatments for cables was conducted with an imaginary nuclear power plant for training using a deterministic fire analysis code. The imaginary nuclear power plant for the training consisted of a reactor containment building and an auxiliary building, including a total of 22 fire areas. The equipment including valves, pumps, emergency diesel generators, switch gears, motor control centers, and logic controllers were located in each fire area of the imaginary plant. It was assumed that each equipment is connected with two cables and that each cable passes through the fire areas along the cable trays. A database containing the information on the equipment and cables for the imaginary plant was constructed for the fire area analysis. The fire area analysis was performed for several assumed MSO scenarios, equipment logics, and cable logics. A mitigation measure using a three hour rated wrap was applied to the failed cables and cable trays after the fire area analysis.

• Nuclear Engineering and Technology
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• v.53 no.2
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• pp.376-385
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• 2021

Probabilistic risk assessment (PRA) has improved its elemental technologies used for assessing external events since the Fukushima Daiichi Nuclear Power Station Accident in 2011. HRA needs to be improved for analyzing tasks performed under extreme conditions (e.g., different actors responding to external events or performing operations using portable mitigation equipment). To make these improvements, it is essential to understand plant-specific and scenario-specific conditions that affect human performance. The Nuclear Risk Research Center (NRRC) of the Central Research Institute of Electric Power Industry (CRIEPI) has developed an HRA guide that compiles qualitative analysis methods for collecting plant-specific and scenario-specific conditions that affect human performance into "narratives," reflecting the latest research trends, and models for analysis of tasks under extreme conditions.

• Magazine of the Korea Concrete Institute
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• v.14 no.4
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• pp.49-55
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• 2002

레미콘의 생산방식은 콘크리트의 비빔을 정치식 배치플랜트(stationary batch plant)내의 고정믹서로 행하는가, 아니면 운반장비인 트럭 믹서(truck mixer)의 드럼으로 행하는가에 따라서 일반적으로 센트럴믹스(central mix), 쉬링크믹스(shrink mix), 트럭 믹스의 3가지로 분류된다.(중략)

• Journal of Energy Engineering
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• v.29 no.1
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• pp.52-57
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• 2020

OLM(On-Line Maintenance) is PM(Preventive Maintenance) activity of safety related equipment during running of Nuclear Power Plants. Korea Hydro & Nuclear Power-co.(KHNP) and regulator institute already reviewed the adoption of on-line maintenance in 2010 but now because of changing conditions of nuclear industry it has been halted. Even though that, OLM is one of the most effective programs to enhance safety and operability of Nuclear power plant. Therefore this paper introduce the strengths of OLM and explain why we should apply to Nuclear power plant.

• Fire Science and Engineering
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• v.33 no.6
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• pp.43-52
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• 2019

A walk-down procedure for fire modeling of nuclear power plants, based on deterministic fire protection requirements, was developed. The walk-down procedure includes checking the locations of safety shutdown equipment and cables that are not correctly indicated on drawings and identifying the existence and location of combustibles and ignition sources. In order to verify the performance of the walk-down procedure developed in this study, a sample of important equipment and cables were selected for hypothetical multiple spurious operation (MSO) scenarios. In addition, the hypothetical fire modeling scenarios were derived from the selected safe shutdown equipment and cables and an actual walk-down was conducted. The plant information collected through the walk-down was compared to the information obtained from the drawings, so that the collected information may be used as input values for the fire modeling.

• Korean Journal of Computational Design and Engineering
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• v.22 no.2
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• pp.150-161
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• 2017

Effective data exchange among the diverse stakeholders participating in a process plant project is an important issue. ISO 15926 is an international standard to support sharing and integrating of process plant data. iRINGTools is an ISO 15926-based tool used to exchange plant data. To exchange plant data using iRINGTools, the mapping between the data model of a commercial system and ISO 15926 should be preceded. To accomplish this, types and properties of equipment and materials used for plant design should be predefined and these data should be represented as user-defined reference data complying with ISO 15926. Besides, the user-defined reference data should be serviced by a reference data server such that iRINGTools searches reference data from the server and utilizes the data for the model mapping. In this paper, we present a method to construct a reference data server and use it for the model mapping in iRINGTools. The proposed method is verified through experiments of exchanging specifications data of equipment and materials using iRINGTools.

• International Journal of Safety
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• v.2 no.1
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• pp.50-56
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• 2003

There are a lot of uncertainties in the severe accident phenomena and scenarios in nuclear power plants (NPPs) and one of the major issues for severe accident management is the reduction of these uncertainties. The severe accident management aid system using Probabilistic Safety Assessments (PSA) technology is developed for the management staff in order to reduce the uncertainties. The developed system includes the graphical display for plant and equipment status, previous research results by a knowledge-base technique, and the expected plant behavior using PSA. The plant model used in this paper is oriented to identify plant response and vulnerabilities via analyzing the quantified results, and to set up a framework for an accident management program based on these analysis results. Therefore the developed system may playa central role of information source for decision-making for severe accident management, and will be used as a training tool for severe accident management.