• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.7
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• pp.101-107
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• 2013

IEC Standards on lightning protection system specify the use of natural components as down conductors. This paper provides an analysis of problems revealed from our field investigation and survey conducted for the relevant experts in the construction site where natural components are used as down conductors. It also considers a suitable condition for installing natural components as down conductors in accordance with the latest version of the standard. As a result, when rebars of reinforced concrete are used as down conductors, vertical bars consisting of rebars of which thickness is not less than D13($127mm^2$) should be connected by welding, clamps or bound joints, using appropriate connection components conforming to IEC Standards. The lashed joints, however, shall not be applied for down conductors.

• Structural Engineering and Mechanics
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• v.53 no.3
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• pp.589-605
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• 2015

The use of the rigid polyurethane foam (RPF) to strengthen buried structures against blast terror has great interests from engineering experts in structural retrofitting. The aim of this study is to use the RPF to strengthen the buried structures under blast load. The buried structure is considered to study the RPF as structural retrofitting. The Guowei model (Guowei et al. 2010) is considered as a case study. The finite element analysis (FEA) is also used to model the buried structure under shock wave. The buried structure performance is studied based on detonating different TNT explosive charges. There is a good agreement between the results obtained by both the Guowei model and the proposed numerical model. The RPF improves the buried structure performance under the blast wave propagation.

• Fibers and Polymers
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• v.6 no.1
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• pp.79-81
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• 2005

Fuzz on the fabrics, which is the fibers protruded from the fabric surface, is very important in view of appearance quality, since it causes unpleasant appearance on the fabrics and also leads to pilling which makes fabric appearance and soft­ness worse. However, fuzz on fabric surface is measured mostly by subjective methods (human vision) rather than objective methods. Thus, in this study, objective method using image analysis techniques has been developed for the measurement of fuzz on fabric surface. Fuzz on the fabric has also been ranked and rated by experts in order to see the reliability of the results obtained from the fuzz measurement. It was observed that correlation coefficient (r) between rating value and objective mea­surement value was 0.9 and this correlation coefficient value confirmed the reliability of this method.

• Korean Journal of Construction Engineering and Management
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• v.9 no.2
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• pp.136-145
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• 2008

Recently the Ministry of Finance and Economy of Korea launched two new project delivery systems called "Best Value Contract (Design-Bid-Build)" and "Bridging Contract (Design-Build)" in October of 2007 by revising enforcement ordinances of "Act on Contracts to Which the State is a Party". These project delivery systems require the bidders to submit technical proposal adjusted to the project characteristics and objectives for selecting the contractor by evaluating technical proposals. This research aimed to suggest guideline to effectively operate the project delivery systems described above. To reach the goal of the research, the framework of the operation model was developed, which includes the four categories: the standard bidding process, the technical proposal requirements, the technical proposal evaluation criteria, and the award methods. The contents of the four categories above were fulfilled throughout conferring with the advisory experts. In particular, the award methods, which are the important decision-making factor in the perspective of the owner, consist of four types: Low Bid-Fully Qualified, Weighted Criteria, Adjusted Bid, and Adjusted Score. The quantitative features and application criteria of these four types of award methods were suggested throughout the simulation using the virtual case.

• Journal of Engineering Education Research
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• v.5 no.2
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• pp.63-85
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• 2002

This study aims at understanding the current situation of quality assurance on technical qualification that can take the initiative in developing human resources in a technical field and exploring a scheme for improvement. To achieve this goal. the method of quality assurance was examined, the current situation, problems and needs on technical qualification, and foreign cases on the method of quality assurance were analyzed. Based on this. the study proposed the methods of quality assurance on technical qualification and operating system and a follow-up program on technical qualification items. The collection and analysis of the relevant materials, a survey targeting qualification holders and personnel managers in industries as respondents, expert consultations, face-to-face interviews of experts and qualification holders in the technical industry to reflect their opinions were applied for the methodology of the study.

• Journal of Digital Convergence
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• v.12 no.7
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• pp.49-64
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• 2014

This study is to prove the effect of raising the value of the expert knowledge of technical experts or researchers that obtained systematic education on finance and management, on the individual's performance, and to do so, BSC(Balanced ScoreCard) is to be used to analyze how the individual's performance was affected. The results indicates that development and management of substantial programs on finance and management-related educations, with the purpose of inspiring management mind on professional employees, are demanded.

• Journal of Distribution Science
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• v.18 no.12
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• pp.5-13
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• 2020

Purpose: The objective of this study is to explore and prioritize strategic factors for revitalization of the sports contents distribution industry. Research design, data and methodology: To this end, strategic factors for revitalization of the sports contents distribution industry were explored based on literature review, and 14 experts were consulted to prioritize the factors. Results: Major conclusions deduced are the following: First, the factors were prioritized in order of legal policy factors, contents factors, and technical infrastructure factors. Second, subdomains of legal policy factors were prioritized in order of policy process factors, legislation enactment and revision factors, budget factors, business model factors focusing on sports contents. Third, subdomains of contents factors were prioritized in order of humanware contents factors, sports contents diversification factors, and high-quality sports contents production factors. Fourth, subdomains of technical infrastructure factors were prioritized in order of sports contents service platform factors, technical development and standardization, global distribution channel provision, and distribution metadata standardization. Conclusions: Findings of this study are of significance given that this study stratifies factors of sports contents distribution industry revitalization-about which there have been very few previous studies- analyzed mainly in terms of justifiability and timeliness, and presents preferential business strategies.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.6
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• pp.385-392
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• 2021

When ordering a slurry shield TBM to be used for power cable tunneling, the client organizes an evaluation committee composed of experts, suggest the criteria and evaluation method for technical specifications for supplier selection, and based on the manufacturer's technical proposal were attempted to evaluate and select. It is expected to be referred to as a guideline for future projects to using Shield TBM as one of the methods of verifying performance and quality in advance and securing economic feasibility in the shield TBM tunneling in the recent increasing trend.

• Structural Engineering and Mechanics
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• v.88 no.1
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• pp.13-23
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• 2023

Seismic risk assessment studies are one of the most crucial instruments for mitigating casualties and economic losses. This work utilizes fragility curves to evaluate the seismic risk of single-story precast buildings, which are generally favored in Marmara's organized industrial zones. First, the precast building stock in the region has been categorized into nine sub-classes. Then, seven locations in the Marmara region with a high concentration of industrial activities are considered. Probabilistic seismic hazard assessments were conducted for both the soil-dependent and soil-independent scenarios. Subsequently, damage analysis was performed based on the structural capacity and mean fragility curves. Considering four different consequence models, 630 sub-class-specific loss curves for buildings were obtained. In the current study, it has been determined that the consequence model has a significant impact on the loss curves, hence, average loss curves were computed for each case investigated. In light of the acquired results, it was found that the loss ratio values obtained at different locations within the same region show significant variation. In addition, it was observed that the structural damage states change from serviceable to repairable or repairable to unrepairable. Within the scope of the study, 126 average loss functions were presented that could be easily used by non-experts in earthquake engineering, regardless of structural analysis. These functions, which offer loss ratios for varying hazard levels, are valuable outputs that allow preliminary risk assessment in the region and yield sensible outcomes for insurance activities.

• Nuclear Engineering and Technology
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• v.56 no.10
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• pp.4031-4041
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• 2024

The PSA (Probabilistic Safety Assessment) is presented as a method of comprehensively evaluating the types of accidents that can occur at nuclear power plants. One of the key components to obtain technical success was the introduction of event tree analysis, and its strength and weakness has been reviewed and enhanced with the term, for instance, Integrated Deterministic-Probabilistic Safety Assessment (IDPSA) since 1980s. However, the technical and policy maturity of IDPSA appears to have room for improvement: the terminologies need to be arranged internationally, and there are no official standards or guidelines for the method itself. Due to a misperception of IDPSA, there are even concerns that appropriate contribution in risk assessment cannot be made. For this reason, surveys and focus group interviews, sharing development experiences, and the direction of regulation and R&D on IDPSA were conducted targeting PSA experts in Korea. In order to support such process, authors have structured an overview of the development history and technical features of IDPSA. Finally, we will explore the ways to achieve synergy between the deterministic safety analysis and PSA, which may the origin of motivation how to deal with dynamic variability more properly such that an undue risk can be minimized.