• Journal of the Korean Geotechnical Society
• /
• v.30 no.1
• /
• pp.49-63
• /
• 2014

Bearing capacity factor $N_{\gamma}$ and shape factor were studied for rigid strip and circular footings with a rough base on sand by numerical modelling considering the effect of dilation angle. The numerical model was developed with an explicit finite difference code. Loading procedures and interpretation methods were devised in order to shorten the running time while eliminating the exaggeration of the reaction caused by the explicit scheme. Using the Mohr-Coulomb plasticity model with associated (${\psi}={\phi}$) and nonassociated (${\psi}$ < ${\phi}$) flow-rules, the bearing capacity factor $N_{\gamma}$ was evaluated for various combinations of internal friction angles and dilation angles. Bearing capacity factor decreased as the dilation angle was reduced from the associated condition. An equation applicable to typical sands was proposed to evaluate the relative bearing capacity for the nonassociated condition compared to the associated condition on which most bearing capacity factor equations are based. The shape factor for the circular footing varied substantially when the plane-strain effect was taken into account for the strip footing. The numerical results of this study showed closer trends with the previous experimental results when the internal friction angle was increased for the strip footing. Discussions are made on the reason that previous equations for the shape factor give different results and recommendations are made for the appropriate design shape factor.

• Journal of Korea Technology Innovation Society
• /
• v.17 no.2
• /
• pp.289-308
• /
• 2014

We analyze the risk factors identified for ex-ante evaluation regarding government R&D programs. In particular, we empirically examined to what extent each risk factor is perceived to be important by the stage of R&D, technology field, researcher's career and experience. The empirical results show that technology risk is perceive to be less important for basic research, while market risk more perceived to be important in the IT field. Political risk is perceived to be less important for the university faculty, while researchers with government R&D project experience gave more value to legal risk factor.

• Nuclear Engineering and Technology
• /
• v.46 no.1
• /
• pp.81-92
• /
• 2014

This study suggests 5 evaluation criteria (safety and technology, environmental impact, economic feasibility, social factors, and institutional factors) and 24 evaluation indicators for a NFC (nuclear fuel cycle) derived using factor analysis. To do so, a survey using 1 on 1 interview was given to nuclear energy experts and local residents who live near nuclear power plants. In addition, by conducting a factor analysis, homogeneous evaluation indicators were grouped with the same evaluation criteria, and unnecessary evaluation criteria and evaluation indicators were dropped out. As a result of analyzing the weight of evaluation criteria with the sample of nuclear power experts and the general public, both sides recognized safety as the most important evaluation criterion, and the social factors such as public acceptance appeared to be ranked as more important evaluation criteria by the nuclear energy experts than the general public.

• Microbiology and Biotechnology Letters
• /
• v.50 no.4
• /
• pp.533-547
• /
• 2022

This study investigated the hair growth effect of Schisandra chinensis extract (TS-SC) and TS-SC fermented by Lactobacillus plantarum (TS-SCLF) on human dermal papilla cells (hDPCs). The production of vascular endothelial growth factor (VEGF), insulin-like growth factor 1 (IGF-1), keratinocyte growth factor/fibroblast growth factor 7 (KGF/FGF-7) and hepatocyte growth factor (HGF), transforming growth factor beta 1 (TGF-β1) were examined. The secretion rates of VEGF and KGF/FGF-7 were high in TS-SC, and the secretion rates of IGF-1 and HGF were high in TS-SCLF. TGF-β1 was inhibited in a concentration-dependent manner in all samples. Gene expression of VEGF, IGF-1, KGF, HGF and alkaline phosphatase, relevant to hair growth, were examined. The data revealed that TS-SC and TS-SCLF successfully promoted hair growth in hDPCs. The IGF-1 gene was expressed in a dose-dependent manner in TS-SCLF. These results indicate that TS-SC and TS-SCLF fermented extract effectively promoted hair growth and gene expression relevant to hair growth in hDPCs. Used in clinical trials the test substance 'CMK-LPF01' showed a statistically significant increase in the number of hairs at 8 weeks, 16 weeks, and 24 weeks compared to before product use, and a change in hair growth, a secondary efficacy evaluation variable. Through additional research in the future, it is expected that "CMK-LPF01" can be developed as a functional material that can help alleviate symptoms of hair loss.

• Proceedings of the KIEE Conference
• /
• 1996.07a
• /
• pp.306-308
• /
• 1996

The demands of minimizing the reactive power and reducing the current harmonics are increasing nowdays. The inverter airconditioner needs high inductive power and it operates with wide load ranges. Conventionally, an huge LC passive filter is used in airconditioner to improve the power factor and to reduce current harmonics which doesn't give good results. In this paper, a design of active power factor correction(APFC)circuit for inverter airconditioner is described. To improve the P.F and reduce the current THD, average current controlled APFC is designed and tested. The problems of APFC implementation, their solution and testing results are described.

• Proceedings of the Korea Technology Innovation Society Conference
• /
• 2004.05a
• /
• pp.48-56
• /
• 2004

To perform R&D program, it is necessary to invest input factor(I/F). And these factor are converted to output factors(O/F) at the end of R&D program. Pee. reviewers evaluate output factors and produce evaluation grades(E/G). This paper try to analyze the relationship to I/F, O/F and E/G, According to the analysis results, the relation between I/F and E/G is as weak as the relation between O/F and E/G. The strength of relationship is relatively very strong in the relation between I/F and O/F

• New & Renewable Energy
• /
• v.7 no.1
• /
• pp.22-28
• /
• 2011

The surface solar radiations were calculated and analyzed with spatial resolutions (4 km and 1 km) using by GWNU (Gangneung-Wonju National University) solar radiation model. The GWNU solar radiation model is used various data such as aerosol optical thickness, ozone amount, total precipitable water and cloud factor are retrieved from Moderate Resolution Imaging Spectrometer (MODIS), Ozone Monitoring Instrument (OMI), MTSAT-1R satellite data and output of the Regional Data Assimilation Prediction System(RDAPS) model by Korea Meteorological Administration (KMA), respectively. The differences of spatial resolutions were analyzed with input data (especially, cloud factor from MTSAT-1R satellite). And the Maximum solar radiation by GWNU model were found in Andong, Daegu and Jinju regions and these results were corresponded with the MTSAT-1R cloud factor.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2000.11a
• /
• pp.234-237
• /
• 2000

In this paper, the structural, dielectric and piezoelectric properties of the Pb[(S $b_{1}$2/N $b_{1}$2/)$_{0.035}$- $_Mn_{1}$3/N $b_{2}$3/)$_{0.065}$-(Z $r_{0.49}$, $Ti_{0.51}$)$_{0.90}$] $O_3$ ceramics were investigated with respect to the variation of the milling time. Grain size was decreased as the increase of milling time. As the milling time is increased, the particle size of the powder was decreased. Dielectric constant and electromechanical coupling factor (Qm)were slowly increased with the increase of milling time. The highest value of Qm was 1,497 at milling time 8 hour. Temperature coefficient of resonant frequency(TC $F_{r}$) was moved to positive side with the increase of milling time.e.e.e.e.e.e.

• STI Policy Review
• /
• v.8 no.1
• /
• pp.1-22
• /
• 2017

There has been a pronounced increase in research and development (R&D) expenditure in Singapore over the last two decades, with government spending accounting for a sizeable share. This increase has been spurred by public policy emphasis on research and innovation as engines of economic growth. This paper analyses the impact of R&D on economic performance in Singapore from 1978 to 2012 through the use of time series analysis. The Cobb-Douglas based analysis shows a long-run equilibrium relationship between Total Factor Productivity (TFP) and R&D investments. We found that the short-run productivity of R&D in Singapore is comparable to smaller advanced economies in the Organisation for Economic Co-operation and Development (OECD). However, in terms of long-run R&D productivity, Singapore lags slightly behind the smaller OECD nations and far behind the G7 countries. This suggests leakage of value capture and low absorptive capacity in local firms. Possibility of productivity improvements induced by policy changes in the 1990s was considered, but no evidence of significant structural breaks was found. Lastly, Granger causality analysis reveals that public sector R&D augments private sector R&D capital, thus playing an important role in generating externalities and spillover effects. Policy implications and lessons for other middle-income countries are discussed.

• International Journal of Advanced Culture Technology
• /
• v.12 no.1
• /
• pp.34-42
• /
• 2024

This study investigated the academic achievement of science and high school students according to the characteristics of R&E activities in mathematics and science. In addition, based on the survey results, the correlation between R&E activity characteristics and mathematics and science academic achievement was studied through correlation analysis and factor analysis between subjects. There was a difference in academic achievement in mathematics and science according to the characteristics of the R&E activity area, and the experience of R&E activity was found to be closely related to the academic achievement of related subjects. Depending on the area of R&E activity, mathematical and scientific academic achievement was found to be two factors: mathematical logic and natural understanding. Natural understanding factors significantly influenced students' academic achievement in mathematics, physics, and life sciences, and mathematical logic factors significantly influenced the academic achievement of students in chemistry and earth science subjects. In particular, mathematical logic ability was concentrated in excellent physics class students, and natural understanding ability was concentrated in excellent life science class students. Since the characteristics of the R & E activity area greatly influence the academic achievement of mathematics and science, it will significantly contribute to the selection and operation of the R & E activity area of science high school students.