• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.15 no.2
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• pp.1-8
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• 2019

The integrity of the Reactor Pressure Vessel (RPV) is affected by the neutrons bombarding the vessel wall leading to embrittlement. This irradiation-induced embrittlement leads to reduction in the fracture toughness of RPV materials. This paper presents a comparative study of typical Optimized Power Reactor (OPR)1000 reactor pressure-temperature (P-T) limit curves using the pre-2006 American Society of Mechanical Engineers (ASME) editions used in the power plant and the current ASME edition of 2010. The current ASME Code utilizes critical reference stress intensity factor based on the lower bound of static, while the Pre-2006 ASME editions are based the critical reference stress intensity factor based on the lower bound of static, dynamic and crack arrest. Model-Based Systems Engineering approach was used to evaluate ASME Code Section XI Appendix G for generating the P-T limit curves. The results obtained from this analysis indicate decrease in conservatism in P-T limit curves constructed using the current 2017 ASME code, which can potentially increase operational flexibility and plant safety. Hence it is recommended to use ASME code edition after 2006 be used in all operating nuclear power plants (NPPs) to establish P-T limit curve.

• Journal of Construction Engineering and Project Management
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• v.1 no.1
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• pp.25-30
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• 2011

With a focus on different aspects of PMIS in construction projects, various sets of critical success factors (CSFs) have been suggested in the literature such as IS Success Model by various researchers. It is crucial to explore the relative importance and groupings of these factors. This paper aims to identify CSFs associated with Project Management Information System (PMIS) in construction projects, and explore their ranking and underlying relationship. CSFs for PMIS identified through a literature review, and consolidated by interviews and pilot studies with professionals in construction industry. A questionnaire instrument was sent out to experienced users (Construction Manager and Constructor) in Korea, and 253 completed questionnaires were retrieved. To increase the generalizability of the results, the respondents were spread across construction site. Using factor analysis and considering the high importance of the factor, CSFs were grouped into three dimensions. All these three groupings and their relationship were included in a framework for successful PMIS in construction projects. These findings help to clarify what the high prioritized factors are, and could also be used as an assessment tool to evaluate the performance of PMIS and thus help to identify areas for improvement.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.11b
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• pp.213-220
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• 2000

Numerical modeling of cut slope has some limits in simulating the real slopes. In the case of 2D analysis of slope stability, it is assumed that slope is simply straight even when it is concave or convex in plan view. In this study, 3D analysis in curved shape slopes has been conducted for the comparison with 2D analysis in terms of failure mode and factor of safety. For this, 3D analysis by FLAC3D was compared with 2D analysis in plane strain condition and axi-symmetric model condition by FLAC. It was also observed how safety factors of slopes were affected by the variation of the tensile strength and cohesion, which are important variables to decide whether the slope fails or not. 2D analysis of concave slopes under plane strain condition showed much smaller safety factors by 16-40 % errors depending on the radius of curvature of slopes, compared to the more realistic values from 3D analysis. In case of convex slopes, the lower values by 7-10 % has been reported. 2D analysis of axi-symmetric model showed also smaller safety factors by 6-10 % and by 2-4 %, in case of concave and convex slopes, respectively. Such results are expected to contribute to the better understanding of failure process and could be applied for improved design of slopes.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.2
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• pp.65-73
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• 2020

The purpose of this paper is to ascertain the key factors affecting tax compliance among Vietnamese firms in Vietnam. We employ both qualitative and quantitative research methods. Qualitative research has been carried out through focus group discussions with ten chief accountants and tax officers. Quantitative research has been conducted through interviews with 200 firms (chief accountants or financial directors) in Vietnam. Analysis of the model includes the following stages: (i) Cronbach's test for reliability of the scale, (ii) exploratory factor analysis (EFA), (iii) confirmatory factor analysis (CFA), and (iv) structural equation model (SEM). The results of the research show that voluntary tax compliance is directly affected by the three factors of audit probability, corporate reputation and business ownership. The probability of audit and severity of sanctions have the strongest impact on tax compliance. Therefore, the tax authorities need to strengthen the inspection of tax declarations, tax payments and tax refunds of firms. The paper confirms that enforced tax compliance is directly affected by the three factors of audit probability, sanction severity and social norms. Voluntary compliance and compulsory compliance have an effect on tax compliance, though voluntary compliance has a more powerful impact.

• Proceedings of the Ginseng society Conference
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• 1998.06a
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• pp.21-30
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• 1998

Ginseng root has been considered to prevent neuronal degeneration associated with brain ischemia, but experimental proof in support of this speculation is limited. Moreover, few studies have compared the neuroprotective actions of ginseng ingredients with those of peptide growth factors and cytokines isf vivo. Using a gerbil forebrain ischemia model, we demonstrated that the oral administration of red ginseng powder before an ischemic insult prevents delayed neuronal death in the hippocampal CAI field and that a neuroprotective molecule within red ginseng powder is ginsenoside Rbl. The neurotrophic effect of ginsenoside Rbl, when examined in the gerbil ischemia model and in neuronal cultures was as potent as or more potent than the effects of epidermal growth factor, ciliary neurotrophic factor, erythropoietin, prosaposin, interleukin-6 and interleukin-3. Besides the protection of hippocampal CAI neurons against brain ischemia/repercussion injuries, ginsenoside Rbl was shown to prevent place navigation disability, cortical infarction and secondary thalamic degeneration in stroke-prone spontaneous hypertensive rats with permanent occlusion of the unilateral middle cerebral artery distal to the striate branches. These findings may validate the empirical use of ginseng root for the treatment of cerebrovascular diseases

• The Research Journal of the Costume Culture
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• v.21 no.5
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• pp.639-654
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• 2013

Understanding consumers' being well and stylishly dressed is a key for marketers' success in ever changing fashion industry. The purpose of this study is to identify the antecedents of dressing style. As antecedents, personal values and clothing-related variables were considered: this study included physical appearance, materialism, and individualism as personal values and quality conscious, price conscious, and brand conscious as clothing related variables. It was hypothesized that personal values influence dressing style both directly and indirectly through clothing related variables. Data were gathered by surveying university students in Seoul, using convenience sampling. Three hundred eleven questionnaires were used in the statistical analysis, exploratory factor analysis using SPSS and confirmatory factor analysis and path analysis using structural equation modeling. The results showed that all the fit statistics for the variable measures were quite acceptable. In addition, the overall fits of the model suggest that the model fits the data well. The hypothesized relationship test also showed that individualism among personal values directly influences dressing style and that only price consciousness among clothing-related variables influences dressing style. With respect to the relative importance, individualism showed the largest standardized regression weight. The results suggest effective product, price, and promotion strategies for marketers whose target market is style conscious consumers.

• Journal of the Korean earth science society
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• v.28 no.5
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• pp.613-619
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• 2007

Mesoscale low is often observed over the downstream region of the East Sea (or, northwest coast off the Japan Islands) during East-Asia winter monsoon. The low system causes a heavy snowfall at the region. A series of numerical experiments were conducted with the aid of a regional model (MM5 ver. 3.5) to examine the formation mechanism of the mesoscale low. The following results were obtained: 1) A well-developed mesoscale low was simulated by the regional model under real topography, NCEP reanalysis, and OISST; 2) The mesoscale low was simulated under a zonally averaged SST without topography. This implies that the meridional gradient of SST is the main factor in the formation of a mesoscale low; 3) A thermal contrast ($>10^{\circ}C$) of land-sea and topography-induced disturbance served as the second important factor for the formation; 4) Paektu Mountain caused the surface wind to decelerate downstream, which created a more favorable environment for thermodynamic modification than that was found in a flat topography; and 5) The types of cumulus parameterizations did not affect the development of the mesoscale low.

• Korean Institute of Interior Design Journal
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• v.15 no.6 s.59
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• pp.221-228
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• 2006

The purpose of this research is to investigate the tendency of color preference for the elderly in housing. For this, a questionnaire survey was carried out with color chips and 9 photos of the living rooms which were chosen among apartment model houses in Pusan. Preference of color usage was measured by SD scale developed by advertising adjectives for the model houses. The result of this study are as follows: 1) The preferred color image was characterized as soft, warm and simple. The main factors of color image were identified and named as 'dignity factor' and 'personality factor'. 2) The elderly preferred G generally, but R for dominant color of the living room. They distinguished their attitudes about the color by the purpose of color usage. 3) For colors of architectural components of the living room, preferred colors were narrowed Y, YR and R for wall, art wall and floor. Beige was the most popular color in the living room for the elderly. This research can contribute to the basic data of color planning for the elderly housing.

• Korean Journal of Environment and Ecology
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• v.22 no.2
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• pp.113-118
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• 2008

This study was carried out with the aim to provide basic data for efficient park management by analyzing satisfaction factors and estimated regression model through questionnaire survey method for the visitors to Bukhansan National Park in Korea. As a result of analysis, it was found that visitors are satisfied with such variables as 'illegal camping', 'cooking act' and 'padded bills' but extremely unsatisfied with 'waste problem', 'congestion', 'damage of visiting trails' and 'lack of cultural facilities'. In the result of satisfaction factors, it was revealed that 'facility management factor' was found to have the greatest effect on satisfaction degree. In the estimated model by Multiple Regression Analysis, 'damage of natural resources' and 'damage of cultural and historic resources', and 'lack of traffic facilities' were found to affect visitors' satisfaction.

• Steel and Composite Structures
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• v.28 no.2
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• pp.195-207
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• 2018

First-order reliability method (FORM) is enhanced based on the search direction using relaxed conjugate reliability (RCR) approach for the embedded nanocomposite beam under buckling failure mode. The RCR method is formulated using discrete conjugate map with a limited scalar factor. A dynamical relaxed factor is proposed to control instability of proposed RCR, which is adjusted using sufficient descent condition. The characteristic of equivalent materials for nanocomposite beam are obtained by micro-electro-mechanical model. The probabilistic model of nanocomposite beam is simulated using the sinusoidal shear deformation theory (SSDT). The beam is subjected to external applied voltage in thickness direction and the surrounding elastic medium is modeled by Pasternak foundation. The governing equations are derived in terms of energy method and Hamilton's principal. Using exact solution, the implicit buckling limit state function of nanocomposite beam is proposed, which is involved various random variables including thickness of beam, length of beam, spring constant of foundation, shear constant of foundation, applied voltage, and volume fraction of ZnO nanoparticles in polymer. The robustness, accuracy and efficiency of proposed RCR method are evaluated for this engineering structural reliability problem. The results demonstrate that proposed RCR method is more accurate and robust than the excising reliability methods-based FORM. The volume fraction of ZnO nanoparticles and the applied voltage are the sensitive variables on the reliable levels of the nanocomposite beams.