• Wind and Structures
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• 제19권4호
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• pp.443-465
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• 2014

Hyperbolic thin-shell cooling towers have complicated vibration modes, and are very sensitive to the effects of group towers and wind-induced vibrations. Traditional aero-elastic models of cooling towers are usually designed based on the method of stiffness simulation by continuous medium thin shell materials. However, the method has some shortages in actual engineering applications, so the so-called "equivalent beam-net design method" of aero-elastic models of cooling towers is proposed in the paper and an aero-elastic model with a proportion of 1: 200 based on the method above with integrated pressure measurements and vibration measurements has been designed and carried out in TJ-3 wind tunnel of Tongji university. According to the wind tunnel test, this paper discusses the impacts of self-excited force effect on the surface wind pressure of a large-scale cooling tower and the results show that the impact of self-excited force on the distribution characteristics of average surface wind pressure is very small, but the impact on the form of distribution and numerical value of fluctuating wind pressure is relatively large. Combing with the Complete Quadratic Combination method (hereafter referred to as CQC method), the paper further studies the numerical sizes and distribution characteristics of background components, resonant components, cross-term components and total fluctuating wind-induced vibration responses of some typical nodes which indicate that the resonance response is dominant in the fluctuating wind-induced vibration response and cross-term components are not negligible for wind-induced vibration responses of super-large cooling towers.

• 한국콘텐츠학회논문지
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• 제21권8호
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• pp.108-122
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• 2021

본 연구는 서비스스케이프가 다른 서비스품질에 대한 선행변수로서 서비스 품질에 대한 지각과 서비스 만족, 서비스에 대한 충성도를 형성하는 과정에 대한 영향을 조사하였다. 이에 위해 서울지역 프랜차이즈 커피전문점 소비자 300명을 조사하여, SPSS 24.0과 AMOS 24.0 버전을 이용하여 분석하였다. 연구결과는 다음과 같다. 첫째, 서비스스케이프를 구성하는 세 개의 하위 잠재요인인 주변요인, 디자인요인, 청결요인의 구조방정식 계수가 모두 정(+)의 방향으로 유의하게 나타났다. 둘째, 서비스스케이프는 기능적인 품질과 기술적인 품질에 긍정적인 영향을 주는 것으로 나타난 반면 서비스스케이프의 서비스만족에 대한 직접적인 영향은 유의하지 않은 것으로 나타났다. 셋째, 서비스스케이프가 기능적인 품질과 기술적인 품질을 통해 서비스 만족과 서비스 충성도에 영향을 주는 것으로 나타났다. 즉, 서비스스케이프는 예상되는 서비스 품질에 대한 단서로서 다른 서비스 요인들에 대한 소비자의 품질 지각에 영향을 주고, 서비스 만족과 서비스 충성도의 형성과정에 긍정적인 영향을 준다는 것을 입증하였다.

• KDI Journal of Economic Policy
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• 제45권1호
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• pp.69-86
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• 2023

Regulatory sentiment refers to the market's subjective evaluation of regulatory reform and is one of the most widely adopted indicators to those charged with implementing and diagnosing regulatory policies. The use of regulatory sentiment in advanced analysis has become universal, albeit it is often limited due to difficulties in articulating consistent and objective quantitative indicators that can meticulously reflect market sentiment overall. Thus, despite ample effort by scholars to read the economic impact of regulatory sentiment in the real economy, causal links are difficult to spot. To fill this gap in the literature, this study analyzes a regulatory sentiment index and economic performance indicators through a text analysis approach and by inspecting diverse tones in media articles. Using different stages of tests, the paper identifies a causal relationship between regulatory sentiment and actual economic activities as measured by private consumption, facility investment, construction investment, gross domestic investment, and employment. Additionally, as a result of analyzing one-unit impulse of regulatory perception, the initial impact on economic growth and private investment was found to be negligible; this was followed by a positive (+) response, after which it converged to zero. Construction investment showed a positive (+) response initially, which then rapidly changed to a negative (-) response and then converged to zero. Gross domestic investment as the initial effect was negligible after showing a positive (+) reaction. Unfortunately, the facility investment outcome was found to be insignificant in the impulse response test. Nevertheless, it can be concluded that it is necessary and important to increase the sensitivity to regulations to promote the economic effectiveness of regulatory reforms. Thus, instead of dealing with policies with the vague goal of merely improving regulatory sentiment, using regulatory sentiment as an indicator of major policies could be an effective approach.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 춘계 학술기술논문발표대회 논문집
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• pp.113-117
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• 2005

The ceramic metal resin paints for waterproof and anti corrosion is not long history in development of materials even many actual result. So far, no standard have been given to construction and maintenance method, Quality and property, it is real state that cannot afford to proper quality control in job site or production. This study has been test for the ceramic metal resin paints for water and anti corrosion, as the result, it have proper performance of job site and mechanical performance of compare to other existing. In particular, tensile strength indicates more high about $14.1N/mm^2$ than epoxy resin paints, and in elongation per unit length is more high It is shows having better adhesive strength than epoxy resin paint for crack on the concrete structure. Moreover, The ceramic metal paint for water and corrosion proofing have to have main performance is watertightness and resistance for external impact, chloride ion permeation, drinkable water elution.

• 한국연소학회지
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• 제11권4호
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• pp.9-13
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• 2006

Recent advances in energetic materials modeling and high-resolution hydrocode simulation enable enhanced computational analysis of bio-medical treatments that utilize high-pressure shock waves. Of particular interest is in designing devices that use such technology in medical treatments. For example, the generated micro shock waves with peak pressure on orders of 10 GPa can be used for treatments such as kidney stone removal, transdermal micro-particle delivery, and cancer cell removal. In this work, we present a new computational methodology for applying the high explosive dynamics to bio-medical treatments by making use of high pressure shock physics and multi-material wave interactions. The preliminary calculations conducted by the in-house code, GIBBS2D, captures various features that are observed from the actual experiments under the similar test conditions. We expect to gain novel insights in applying explosive shock wave physics to the bio-medical science involving drug injection. Our forthcoming papers will illustrate the quantitative comparison of the modeled results against the experimental data.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.436-437
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• 2006

Porcelain insulators have generally been used in Korea but polymer insulators which are superior in that they are light weight, explosion proof, impact proof, economical with construction characteristics, have been in use for the 154kV transmission line since 1999 following a worldwide trend towards the reduced weight, simplification and compact usage of new material insulators. However there have been approximately 500 cases of forest fires in Korea, so the transmission lines that for the most part pass through mountainous areas have been highly effected and the highly polymerized compound polymer insulator has raised concern about reliability in cases of exposure to forest fires. Therefore for the reliability assessment of the effect of forest fires on polymer insulators, mechanical and electrical characteristics are analyzed by an artificial flare test device and transmission facility surrounding conditions along with forest fire characteristics are surveyed. In addition to this, actual 90kV energized transmission line was tested with an artificial forest fire and the expanded usage of polymer insulators is presented through the analysis of mechanical and electrical characteristics and physical properties, and a study on the influence of forest fires on polymer insulators.

• Nuclear Engineering and Technology
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• 제52권6호
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• pp.1318-1326
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• 2020

Structural modification in the electrical cabinet is investigated by a proposed procedure that comprises of an experimental, analytical and numerical solution. This research emphasizes the linear dynamic analysis of the cabinet that is studied under the seismic excitation to demonstrate the real behavior of the cabinets in NPP. To this end, an actual electric cabinet is experimentally tested using an impact hammer test which reveals the fundamental parameters of the cabinet. The Frequency-domain decomposition (FDD) method is used to extract the dynamic properties of the cabinet from the experiment which is then used for numerical modeling. To validate the dynamic properties of the cabinet an analytical solution is suggested. The calibrated model is analyzed under the floor response obtained from the Connecticut nuclear power plant structure excited by Tabas 1978 (Mw 7.4) earthquake. Eventually, the grouping effect of the cabinets is proposed which represents the influence on the dynamic modification. This grouping of the cabinets is described more sophisticatedly by the theoretical understating, which results in a significant change in the seismic response. Considering the grouping effects will be helpful in the assessment of the real seismic behavior, design, and performance of cabinets.

• Journal of Information Technology Applications and Management
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• 제22권1호
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• pp.17-36
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• 2015

Many companies are now trying to utilize SNS (social network service) by building it as marketing communication platform that delivers marketing messages and builds customer relationship. This study investigates the factors affecting consumers' intention to use of brand's SNS identity page (e.g., fan page in Facebook). It specifically focuses on four social support functions -self-esteem, informational, emotional and social networking support-in virtual space. Research model attempts to explore the impact of social supports on brands' SNS identity page adoption with modified technology acceptance model which includes perceived usefulness, ease of use and enjoyment. Empirical study adopts SEM (structural equation modelling) to test research model. The result indicates that perceived ease of use is influenced by informational support, and perceived usefulness is influenced by informational, emotional, and self-esteem support. And perceived enjoyment is influenced by emotional support. In addition, it reveals that there were no significant effects of social networking support on both perceived usefulness and enjoyment. These findings provide managerial implications for attracting potential and actual customers to brand's SNS identity page. And it also suggests the importance of managing sociability in brand's SNS identity page to make it as marketing communication platform.

• Steel and Composite Structures
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• 제35권1호
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• pp.93-109
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• 2020

Developed from conventional concrete filled steel tubular (CFST) members, concrete-encased CFST has attracted growing attention in building and bridge practices. In actual construction, the inner CFST is erected prior to the casting of the outer reinforced concrete part to support the construction preload, after which the whole composite member is under sustained service load. The complex loading sequence leads to highly nonlinear material interaction and consequently complicated structural performance. This paper studies the full-range behaviour of concrete-encased CFST columns with initial preload on inner CFST followed by sustained service load over the whole composite section. Validated against the reported data obtained from specifically designed tests, a finite element analysis model is developed to investigate the detailed structural behaviour in terms of ultimate strength, load distribution, material interaction and strain development. Parametric analysis is then carried out to evaluate the impact of significant factors on the structural behaviour of the composite columns. Finally, a simplified design method for estimating the sectional capacity of concrete-encased CFST is proposed, with the combined influences of construction preload and sustained service load being taken into account. The feasibility of the developed method is validated against both the test data and the simulation results.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2006년도 제32회 KOSCO SYMPOSIUM 논문집
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• pp.213-217
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• 2006

Recent advances in energetic materials modeling and high-resolution hydrocode simulation enable enhanced computational analysis of bio-medical treatments that utilize high-pressure shock waves. Of particular interest is in designing devices that use such technology in medical treatments. For example, the generated micro shock waves with peak pressure on orders of 10 GPa can be used for treatments such as kidney stone removal, trans-dermal micro-particle delivery. and cancer cell removal. In this work, we present a new computational methodology for applying the high explosive dynamics to bio-medical treatments by making use of high pressure shock physics and multi-material wave interactions. The preliminary calculations conducted by the in-house code, GIBBS2D, captures various features that are observed from the actual experiments under the similar test conditions. We expect to gain novel insights in applying explosive shock wave physics to the bio-medical science involving drug injection. Our forthcoming papers will illustrate the quantitative comparison of the modeled results against the experimental data.