• Wind and Structures
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• v.25 no.3
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• pp.261-282
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• 2017

The probabilistic information of directional extreme wind speeds is important for precisely estimating the design wind loads on structures. A new joint probability distribution model of directional extreme wind speeds is established based on observed wind-speed data using multivariate extreme value theory with the t-Copula function in the present study. At first, the theoretical deficiencies of the Gaussian-Copula and Gumbel-Copula models proposed by previous researchers for the joint probability distribution of directional extreme wind speeds are analysed. Then, the t-Copula model is adopted to solve this deficiency. Next, these three types of Copula models are discussed and evaluated with Spearman's rho, the parametric bootstrap test and the selection criteria based on the empirical Copula. Finally, the extreme wind speeds for a given return period are predicted by the t-Copula model with observed wind-speed records from several areas and the influence of dependence among directional extreme wind speeds on the predicted results is discussed.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.8 no.4
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• pp.25-35
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• 2013

The main objective of this study is to investigate the structural relation between antecedents and consequences of web sites' trust of venture company. It examines consumer perceptions trust in a web site and address following research questions; what factors influence consumer trust in a web site and what specific web site cues are associated with trust, satisfaction, and intention? We test our hypothesis in a empirical data from 123 consumers across 3 web sites of venture companies. By factor analysis, the results show that web site characteristics are such as design, business function, interface, technology, community, and contents of each web site. We also find that web site characteristics such as design, interface, technology, and community can influence significantly satisfaction of web site, and design and contents of web site can influence consumer's trust. And the results show that trust influence behavioral intention through the satisfaction. The results offer important implication for web site strategies of venture company that include the manipulation of factors influencing web site trust. And the future directions of the present research are discussed.

• Structural Engineering and Mechanics
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• v.85 no.5
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• pp.679-691
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• 2023

Many codes allow designers to use the bending moment diagram computed by elastic analysis and modify it by a certain amount of moment redistribution (MR) to account for plastic behaviour of continuous beams. However, several researchers indicated that the MR at the ultimate limit state (𝛽_u) for some beams deviate significantly from the specified values of various codes. This paper examines the applicability of the provisions on 𝛽_u in ACI 318-19 and Eurocode 2 through numerical investigations and comprehensively explores the influencing factors. The results show that some parameters not considered in those codes influence 𝛽_u to a certain extent, where the ratio of tensile reinforcement ratio at intermediate support to tensile reinforcement ratio at midspan (𝜌_s1/𝜌_s2) and load type are crucial parameters to consider. The specific combination of these two parameters may make the codes overestimate or significantly underestimate the 𝛽_u. On the other hand, the yield state of both critical sections is found to have an important influence on the influence degree of each parameter on 𝛽_u. The yield conditions are investigated, and an empirical judgment equation is proposed. In addition, the influence laws of the critical parameters on 𝛽_u have been further proved by theoretical derivation. Finally, due to 𝜀_t is found to have a better linear correlation with 𝛽_u than x_u/d, equations as a function of 𝜀_t for predicting the 𝛽_u of continuous beams under the two loads are proposed, respectively.

• The Journal of Industrial Distribution & Business
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• v.10 no.9
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• pp.53-60
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• 2019

Purpose - The objective of this paper is to discover if there exists a relationship between the economic index and distribution industry index in Korean. Because of the distribution industry boom in the recent years, a lot of interest in the relationship between the economic index and distribution industry index in Korean and the economy has been generated. This article examine on the mutual influence between economic index and distribution industry index in Korean. Research design, data, and methodology - For this purpose, we use the vector-auto regression model, impulse response function and variance decomposition of the economic index and distribution industry index, Granger causality test using weekly data on the economic index and distribution industry price index in korea. The sample period is covering from January 2, 2010 to August 31, 2019. The VAR model can also be linked to cointegration analysis. Cointegration Analysis makes possible to find a mechanism causing x and y to move around a long-run equilibrium (Engle and Granger, 1987). This equilibrium means that external shocks may separate the series temporarily at any particular time, but there will be an overall tendency towards some type of long-run equilibrium. If variables are found to have this tendency they are said to be cointegrated and a long-run relationship between these series is established. These econometric tools have been applied widely into economics and business areas to analyze intertemporal linkages between different time series. Results - This research showed following main results. First, from the basic statistic analysis of the economic index and distribution industry index in Korean, the economic index and the distribution industry index in korea have unit roots. Second, there is at least one cointegration between the economic index and distribution industry index in Korean. Finally, the correlation between of the economic index and the distribution industry index in korea is (+) 0.528876. Conclusions - We find that the distribution industry price index Granger cause the economic index in korea. As a consequence, the distribution industry index affect the economic index in Korean. The distribution industry index to the economic index is stronger than that from the economic index to the distribution industry index.

• Asia-Pacific Journal of Business
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• v.15 no.2
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• pp.143-157
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• 2024

Purpose - This paper aims to analyze the relationship and correlation between the stock markets of Korea, the US, China, and Japan before and after the outbreak of COVID-19. Design/methodology/approach - This study conducted an empirical analysis using the stock market data from January 2016 to June 2023 for the representative market indices of Korea, the US, China, and Japan. The analysis employed the VAR model, Granger causality test, impulse response function, and variance decomposition. Findings - Analyzing the relationships of these stock markets before and after the outbreak of COVID-19, we obtained the following results. (i) The influence of the U.S. stock market was found to be absolute regardless of the COVID-19 period, and the rise in the U.S. stock market led to rises in other stock markets. (ii) The Chinese stock market had a significant negative impact on the U.S., Korean, and Japanese stock markets before COVID-19, but this influence disappeared after COVID-19. This suggests that the Chinese market exhibited unique characteristics different from the global market after COVID-19. (iii) Analyzing the period excluding the first quarter of 2020, when global stock market volatility was extremely high due to the spread of COVID-19, we found that the results were very similar to the analysis including the first quarter of 2020. Therefore, it is difficult to argue that the increased uncertainty during this period distorted the relationships among the stock markets of these four countries. Research implications or Originality - We anticipate that these findings will offer valuable insights for both individual and institutional investors, aiding them in portfolio diversification and risk mitigation.

• Science of Emotion and Sensibility
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• v.17 no.2
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• pp.63-76
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• 2014

Although most behavioral reaction times (RTs) for cognitive tasks exhibit positively skewed distributions, the majority of studies primarily rely on a measure of central tendency (e.g. mean) which can cause misinterpretations of data's underlying property. The purpose of current study is to introduce procedures for describing characteristics of RT distributions, thereby effectively examine the influence of experimental manipulations. On the basis of assumption that RT distribution can be represented as a convolution of Gaussian and exponential variables, we fitted the ex-Gaussian function under a maximum-likelihood method. The ex-Gaussian function provides quantitative parameters of distributional properties and the probability density functions. Here we exemplified distributional analysis by using empirical RT data from two conventional visual search tasks, and attempted theoretical interpretation for setsize effect leading proportional mean RT delays. We believe that distributional RT analysis with a mathematical function beyond the central tendency estimates could provide insights into various theoretical and individual difference studies.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.2
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• pp.380-386
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• 2002

Damage behaviors induced in silicon carbide by an impact of particle having different material and size were investigated. Especially, the influence of the impact velocity of particle on the cone crack shape developed was mainly discussed. The damage induced by spherical impact was different depending on the material and size of particles. Ring cracks on the surface of specimen were multiplied by increasing the impact velocity of particle. The steel particle impact produced larger ring cracks than that of SiC particle. In the case of high velocity impact of SiC particle, radial cracks were produced due to the inelastic deformation at the impact site. In the case of the larger particle impact, the damage morphology developed was similar to the case of smaller particle one, but a percussion cone was farmed from the back surface of specimen when the impact velocity exceeded a critical value. The zenithal angle of cone cracks developed into SiC material decreased monotonically with increasing of the particle impact velocity. The size and material of particle influenced more or less on the extent of cone crack shape. An empirical equation, $\theta$= $\theta$$\sub$st/, v$\sub$p/(90-$\theta$$\sub$st/)/500 R$\^$0.3/($\rho$$_1$/$\rho$$_2$)$\^$$\frac{1}{2}$/, was obtained as a function of impact velocity of the particle, based on the quasi-static zenithal angle of cone crack. It is expected that the empirical equation will be helpful to the computational simulation of residual strength in ceramic components damaged by the particle impact.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.9 no.5
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• pp.115-127
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• 2014

The national Entrepreneurial policy of Start-up assists the young and college students to be raised as entrepreneur in various ways seeking solution for serious unemployment problem. Many young generation start-up a business without prior knowledge and experience in management that end up as a case of failure rather than success. Many young pre-entrepreneur are afraid of Start-up and hesitate or give up before start. Now many Entrepreneurship education contents and Entrepreneurship mentoring programs are being provided for pre-entrepreneur. Especially, Entrepreneurship mentoring programs's importance to ease off these fear and anxiety is recognized and Mentoring program's part and contents are being enhanced in Entrepreneurship education content. In this study, the influence of Entrepreneurship mentoring program to young and brilliant entrepreneur who wants to start a business will be explained. The function of Entrepreneurship mentoring to improvement of entrepreneurial capability will be anaylzed and by using the function of Entrepreneurship mentoring and entrepreneurial capability, the moderating effect of start-up preliminary period and start-up aim period is examined. The results of as regression analysis, the study found out the function of Entrepreneurship mentoring has a positive significant influence with entrepreneurial capability which means technological competence and creativity competence. For the moderating effect of start-up preliminary period and start-up aim period, it is found out that the effect does not have a significant influence on the function of Entrepreneurship mentoring and also technological competence, but on creativity competence, significant influence was found. However, after looking at the moderating effect that is considered to be related to entrepreneurial capability, for the function of mentoring only the effect on start-up preliminary period.

• Geomechanics and Engineering
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• v.21 no.5
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• pp.423-432
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• 2020

Hydraulic conductivity is one of the engineering properties of soil. This study focusses on the influence of cement content on the hydraulic conductivity of cemented sand, which is investigated based on the results from numerical analysis and laboratory testing. For numerical analysis the cemented samples were scanned using X-ray Computed Tomography (CT) while laboratory testing was carried out using a triaxial setup. Numerical analysis enables us to simulate flow through the sample and provides insight to the microstructure. It quantifies the pore volume, proportion of interconnected voids and pore size distribution in both cemented and uncemented samples, which could be computed only through empirical equations in case of laboratory testing. With reduction in global voids, the interconnecting voids within the samples also reduce with cement content. Gamma cumulative distribution function is used to predict the percentage of voids lesser than a given pore volume. Finally, the results obtained from both numerical analysis and laboratory testing are compared.

• Journal of Nutrition and Health
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• v.15 no.4
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• pp.290-300
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• 1982

The study deals with the empirical research on the condition of nutrient intake of low income class which be represented by urban slum and rural area, with the analysis of the factors which might influence on the prevalent condition of nutrient- intake. The method of the research was based on the spot-survey with questionaires. The result is that the levels of nutrient-intake are below the standard requirement level of nutrients in both of urban slum and rural area. The level of nutrient intake in urban slum lies in approximately 50% of the standard requirement level and 80% of the standard requirement level in rural area. The extent of malnutrition was explained in terms of the amount of calorie, protein, calcium and iron. More than half of the population in the community are below the standard requirement level of the nutrient- intake. The problem of malnutrition was serious in urban slum than in rural areas, which made a good contrast with the result of Peru study. Deficiency in calcium was most serious. The factor analysis of the prevalent condition of malnutrition in low class suggests that 1) The function of local market in supplying food is not so effective in the sense that the quality of the foods purchased id the local market is poor. 2) Low level of knowledge, the consequent ignorance and the indifference to the nutrition and the low income led to malnutrition. The level of income and the education were significantly correlated to the nutrient-intake.