• Journal of Korean Society of Steel Construction
• /
• v.17 no.5 s.78
• /
• pp.561-568
• /
• 2005

The object of this paper is to determine appropriateness for use of high-strength tensile bar as a tension web member. The gap K-joint of tensile bar types were compared with gap K-joint of square hollow section (SHS) types. For the same width-to-thickness ratio ($2{\gamma}=33.3$ ), tests were performed on four specimens of the SHS type and eight specimens of the tensile bar type. The comparison of capacity with the experimental results showed a capacity of the SHS type joint to be higher than that of the tensile bartype joint for the same brace-to-chord width ratio. Moreover, the capacity of the SHS type joints increased proportionally to the width ratio ${\beta}$), while tensile bar type joints increased as the tension width ratio (${\beta}2$). In failure mode, SHS-type specimens showed local buckling of the compression brace and plastic failure was observed between the tension brace and chord face, and with the tensile bar type specimens there appeared punching shear failure of the chord face at the toe of the connection plate. It is, therefore, concluded that width-to-thickness ratio should be lower than that of the hollow-section type and the relation between tension and compression width ratio should be considered.

• International Commerce and Information Review
• /
• v.15 no.3
• /
• pp.3-24
• /
• 2013

This study has examined the relationship between entrepreneurial orientation(EO), dynamic capability(DC) and export performance of international new ventures(INVs). Also, the moderating effect of external environment factors(the hostility at domestic markets and the industrial dynamics) were analysed. Empirical analysis was performed on 101 INVs. It was conducted using the PLS(Partial Least Square). The result of empirical analysis showed that there is a positive relationship between EO, DC and export performance. The result of moderating effect showed that two external environment factors have positive moderating effect on the relationship between EO and DC. However, there was not moderating effect of external environment factors on the relationship between DC and export performance.

• KDI Journal of Economic Policy
• /
• v.14 no.1
• /
• pp.121-145
• /
• 1992

This paper examines characteristics of time series data related to the construction investment(stationarity and time series components such as secular trend, cyclical fluctuation, seasonal variation, and random change) and surveys predictibility, fitness, and explicability of independent variables of various models to build a short-term construction investment forecasting model suitable for current economic circumstances. Unit root test, autocorrelation coefficient and spectral density function analysis show that related time series data do not have unit roots, fluctuate cyclically, and are largely explicated by lagged variables. Moreover it is very important for the short-term construction investment forecasting to grasp time lag relation between construction investment series and leading indicators such as building construction permits and value of construction orders received. In chapter 3, we explicate 7 forecasting models; Univariate time series model (ARIMA and multiplicative linear trend model), multivariate time series model using leading indicators (1st order autoregressive model, vector autoregressive model and error correction model) and multivariate time series model using National Accounts data (simple reduced form model disconnected from simultaneous macroeconomic model and VAR model). These models are examined by 4 statistical tools that are average absolute error, root mean square error, adjusted coefficient of determination, and Durbin-Watson statistic. This analysis proves two facts. First, multivariate models are more suitable than univariate models in the point that forecasting error of multivariate models tend to decrease in contrast to the case of latter. Second, VAR model is superior than any other multivariate models; average absolute prediction error and root mean square error of VAR model are quitely low and adjusted coefficient of determination is higher. This conclusion is reasonable when we consider current construction investment has sustained overheating growth more than secular trend.

• International Commerce and Information Review
• /
• v.14 no.3
• /
• pp.113-138
• /
• 2012

This study examined the determinants of export performance of small and medium sized manufacturing companies in Korea. Depending on the existing research, taking entrepreneurship and product differentiation capabilities as antecedents of export performance. In addition, the product differentiation capabilities examined whether the role of the mediating effects between entrepreneurship and export performance. Thus, the purpose of the study is look at the integrated model of entrepreneurship, product differentiation capabilities and export performance building and their relationship. On 152 domestic companies, empirical analysis was performed. Empirical analysis was conducted using the PLS(Partial Least Square). And analysis tools were used SmartPLS2.0. In the results of the analysis, risk tolerance and innovativeness of small and medium sized manufacturing businesses, entrepreneurs and product differentiation competence have positive impact export performance in both. Product differentiation capabilities also confirmed that it have a positive impact on the export performance of small manufacturing export enterprises. In analysis of the mediated effect in product differentiation capacity showed a significant mediated effect between innovativeness and export performance. But mediated effects did not indicate a significant risk tolerance. these results suggests the need to actively pursue innovation that more product differentiation capabilities required in export companies to small and medium-sized manufacturing. In other words, when attempting to highlight product differentiation, based on innovation, rather than risk tolerance. In terms of analyzing the mediated role of product differentiation capabilities, this study has theoretical implications for the future research to look at the antecedents of export performance from the perspective of dynamic capabilities and competitive advantage. Also, practical implications in this regard as the innovativeness and taking risks to all important to CEO of small manufacturing enterprises but, stranger in the foreign market competition environment, the role of innovation product is required on raising product differentiation capabilities are presented.

• Korean Journal of Remote Sensing
• /
• v.32 no.3
• /
• pp.201-220
• /
• 2016

In this study, the net solar radiation fluxes at the surface are retrieved by updating an existing algorithm to be applicable for MODerate resolution Imaging Spectroradiometer (MODIS) observations, in which linear relationships between the solar radiation reflected from the top of atmosphere and the net surface solar radiation are employed. The results of this study have been evaluated through intercomparison with existing Clouds and the Earth's Radiant Energy System (CERES) data products and ground-based data from pyranometers at Gangneung-Wonju National University (GWNU) and the Southern Great Plains (SGP) of observatory of Atmospheric Radiation Measurement (ARM) site. Prior to the comparison of the surface radiation energy in relation to the energy balance of the earth, the radiation energy of the upper part of the atmosphere was compared. As a result, the coefficient of determination was over 0.9, showing considerable similarity, but the Root-Mean-Square-Deviation (RMSD) value was somewhat different, and the downward and net solar-radiation energy also showed similar results. The surface solar radiation data measured from pyranometers at Gangneung-Wonju National University (GWNU) and Atmospheric Radiation Measurement (ARM) observatory are used to validate the solar radiation data produced in this study. When compared to the GWNU, The results of this study show smaller RMSD values than CERES data, showing slightly better agreements with the surface data. On the other hand, when compared with the data from ARM SGP observatory, the results of this study bear slightly larger RMSD values than those for CERES. The downward and net solar radiation estimated by the algorithm of this study at a high spatial resolution are expected to be very useful in the near future after refinements on the identified problems, especially for those area without ground measurements of solar radiation.

• Journal of Korea Multimedia Society
• /
• v.13 no.8
• /
• pp.1183-1193
• /
• 2010

The pyramid graph is well known in parallel processing as a interconnection network topology based on regular square mesh and tree architectures. The enhanced pyramid graph is an alternative architecture by exchanging mesh into the corresponding torus on the base for upgrading performance than the pyramid. In this paper, we adopt a strategy of classification into two disjoint groups of edges in regular square torus as a basic sub-graph constituting of each layer in the enhanced pyramid graph. Edge set in the torus graph is considered as two disjoint sub-sets called NPC(represents candidate edge for neighbor-parent) and SPC(represents candidate edge for shared-parent) whether the parents vertices adjacent to two end vertices of the corresponding edge have a relation of neighbor or sharing in the upper layer of the enhanced pyramid graph. In addition, we also introduce a notion of shrink graph to focus only on the NPC-edges by hiding SPC-edges within the shrunk super-vertex on the resulting shrink graph. In this paper, we analyze that the lower and upper bounds on the number of NPC-edges in a Hamiltonian cycle constructed on $2^n{\times}2^n$ torus is $2^{2n-2}$ and $3{\cdot}2^{2n-2}$ respectively. By expanding this result into the enhanced pyramid graph, we also prove that the maximum number of NPC-edges containable in a Hamiltonian cycle is $4^{n-1}$-2n+1 in the n-dimensional enhanced pyramid.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.7
• /
• pp.123-133
• /
• 2016

The purpose of this study was to examine the part-time work experience of nursing students and its effects on their interpersonal communication competence, self-efficacy and social skills. The study subjects were 362 nursing students in areas S, B, G and G. The relationship between the nursing students' part time work. experience and their general characteristics was analyzed by the Chi-square (${\chi}^2$) test and Fisher's exact test. The interpersonal communication competence originating from the general characteristics, self-efficacy, and difference in the social skills standard among groups were analyzed by the t-test, and analysis of variance (ANOVA). Among the 326 participants, 91.7% had part-time experience and 8.3% had no part-time experience. There was a significant relation between the part-time experience and economic level. Those having a low economic level were more likely to have part time work experience. The interpersonal communication and social skills of the students who had part time work experience when they were middle school students were lower than those who had such experience after high school. Further research is needed to identify precisely the advantages afforded by the part-time work experience of the nursing students.

• Journal of Korea Water Resources Association
• /
• v.43 no.5
• /
• pp.445-453
• /
• 2010

Energy loss at manholes, often exceeding friction loss of pipes under surcharged flow, is considered as one of the major causes of inundation in urban area. Therefore, it is necessary to analyze head losses at manholes, especially in case of surcharged flow. Hydraulic experimental apparatus which can change the manhole shape (square, circular) were installed for this study. In the experiments, two inflows ($Q_1,\;Q_2$) were varied from 0 to $4{\ell}$/sec and 15 combinations were tested in total. The flow ratios $Q_2/Q_3$ were varied from 0 to 1 for a total flow $Q_3$ ($Q_3=Q_1+Q_3$) of 2, 3, and $4{\ell}$/sec, respectively. The variation of head losses were strongly influenced by the lateral inflow because the head loss coefficient increases as the flow ratio $Q_2/Q_3$ increases. There was no significant difference of head loss between square manhole and circular one, and also no large variation of head loss as discharges change. The relation equations between K and $Q_2/Q_3$ were suggested in this paper.

• Culinary science and hospitality research
• /
• v.23 no.2
• /
• pp.104-116
• /
• 2017

The purpose of this study was to conduct an empirical survey on consumer perception and consumption behavior in relation to local food and eco-friendly food. The survey was conducted using 266 consumers who have heard about or purchased local foods and eco-friendly foods centering on Seoul and Gyeonggi-do, and statistical analysis was carried out using SPSS (Version 23.0) to generate descriptive statistical values such as frequency and percentage and implement a Chi-square test. The results showed that consumers purchased local food in large shopping malls, supermarkets, and local food stores, whereas eco-friendly food were usually bought in large shopping malls, supermarkets, and eco-friendly food specialty stores. For local food, consumers bought fruits the most, followed by vegetables, whereas for eco-friendly food, consumers purchased vegetables the most, followed by fruits. The top reason for purchasing local food was its "fresh and high quality," whereas the top reason for buying eco-friendly food was "safety from pesticides and additives." According to results of the Chi-square test, women, unmarried people and younger people turned out to have more experiences in purchasing local foods and eco-friendly foods compared to men, married people and older people, respectively. Although local and eco-friendly food were completely different concepts, results of the study show that consumers were not able to make a clear distinction between the two. Consumer education, therefore, should involve defining the two types of food and spreading awareness on local and organic food to help them made the right choices when buying food.

• The korean journal of orthodontics
• /
• v.31 no.3 s.86
• /
• pp.347-355
• /
• 2001

Maxillary and mandibular anterior dental arches often have the problems of occlusal relation and esthetics by malformations of teeth, congenital missing, et at. Though the clinician usually use the anterior ratio to overcome this problems, he has the limitation of a direct application this ratio to the prediction of anterior occlusal relationship by the change of anterior ratio as dental arch form, intercanine width, segment depth and arch perimeter. So this study examine maxillary and mandibular anterior dental arch forms by least square method using Korean normal occlusion models(man : 20 casts, woman : 20 casts). Maxillary and mandibular anterior dental arches of Korean normal occlusion models are curve fitted to polynomial function, beta function, hyperbolic cosine function in order. And this accuracy of curve fitting is constant regardless of man/woman and maxilla/mandible. The relationships between intercanine width, segment depth, and arch perimeter based on this owe fitted dental arch form are acquired. This relationships will give the prediction of anterior dental arch form and the information of more accurate anterior ratio according to intercanine width.