• Bulletin of the Korean Chemical Society
• /
• v.35 no.2
• /
• pp.397-400
• /
• 2014

Size- and shape-controlled monodisperse wurtzite structured CdS nanorods have been successfully synthesized using a facile solution-based colloidal method. Depending on the control of injection/growth temperatures and the variation of Cd-to-S molar ratios, the morphology of the CdS nanocrystals (NCs) can be adjusted into bullet-like, rod-like, and dot-like shapes. X-ray diffraction (XRD), transition electron microscopy (TEM), and absorption spectroscopy were used to characterize the structure, morphology, and optical properties of as-synthesized CdS NCs. It was found that uniform CdS nanorods could be successfully synthesized when the injection and growth temperatures were very high (> $360^{\circ}C$). The aspect ratios of different shaped (bullet-like or rod-like) CdS NCs could be controlled by simply adjusting the molar ratios between Cd and S.

• Special Issue of the Society of Naval Architects of Korea
• /
• 2015.09a
• /
• pp.85-92
• /
• 2015

In general, when ships are designed, structural strength and fatigue strength must be verified based on the relative rules respectively. In case of Slurry Iron Sand Carrier designed to carry Iron-Sand saturated at water content, there is no special consideration of fatigue strength analysis. However, this vessel is similar to Ore Carrier in consideration of the overall characteristics of loaded cargo and the shape of cargo hold. Therefore we verified fatigue strength based on fatigue analysis procedure of ore carrier in DNV Rules and carried out the study for improving of fatigue strength of Slurry Iron Sand Carrier.

• Journal of the Korean Mathematical Society
• /
• v.6 no.2
• /
• pp.81-83
• /
• 1969

• Magazine of the Korea Concrete Institute
• /
• v.15 no.1
• /
• pp.71-74
• /
• 2003

• Nuclear Engineering and Technology
• /
• v.54 no.5
• /
• pp.1890-1901
• /
• 2022

We have assessed the applicability of the thermal-hydraulic system analysis code, SPACE, to a small modular reactor called SMART. For the assessment, the experimental data from a scale-down integral-test facility, SMART-ITL, were used. It was conformed that the SPACE code unrealistically calculates the safety injection flow rate through the CMT and SIT during a small-break loss-of-coolant experiment. This unrealistic behavior was due to the overprediction of interfacial heat transfer at the steam-water interface in a vertically stratified flow in the tanks. In this study, a special thermal-hydraulic component model has been developed to realistically calculate the interfacial heat transfer when a strong non-equilibrium two-phase flow is formed in the CMT or SIT. Additionally, we developed a special heat structure model, which analytically calculates the heat transfer from the hot steam to the cold tank wall. The combination of two models for the tank are called the special component model. We assessed it using the SMART-ITL passive safety injection system (PSIS) test data. The results showed that the special component model well predicts the transient behaviors of the CMT and SIT.

• Journal of The Korean Astronomical Society
• /
• v.29 no.spc1
• /
• pp.217-218
• /
• 1996

The results of the Crab pulsar observations with the photometrical MANIA (Multichannel Analysis of Nanosecond Intensity Alterations) complex at the 6-m telescope are presented. More than 12 millions photons in UBVR-bands simultaneously with time resolution of $10^{-7}s$ were detected. Using the original software for search for optical pulsar period, we obtained the light curves of the object with time resolution of about 3.3 ${\mu}s$. Their detailed analysis gives the spectral change during pulse and subpulse, the shape of the pulse peaks, which are plateaus (with the duration of about 50${\mu}s$ for the main pulse), limits for an amplitude of fine temporal (stochastic and regular) structure of pulse and sub pulse and the interpulse space intensity. The results of CCD-spectroscopy of the Crab pulsar show that its summarized spectrum is flat. There are no lines, neither emission nor absorbtion ones. Upper limit for line intensity or depth is $3.5\%$ with the confidence probability of $95\%$.

• Journal of the Korean Statistical Society
• /
• v.21 no.2
• /
• pp.179-185
• /
• 1992

A model is proposed for describing agreement between two raters on a nominal categorical scale. This model has a structure of symmetry plus main-diagonal equiprobability, which is a special case of the quasi-symmetry model. An example is given.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 1996.10a
• /
• pp.117-120
• /
• 1996

The objective of this study is to suggest modified Covariance Structure Analysis that combine with existing Multivariate Statistical Method which is used Casual Analysis Method in Management Information. For this purpose, we'll consider special feature and limitation about Correlation Analysis, Regression Analysis, Path Analysis and connect Covariance Structure Analysis with Statistical Factor Analysis so that theoretical casual model compare with variables structure in collecting data. A example is also presented to show the practical applicability of this approach.

• Korean Journal of Organic Agriculture
• /
• v.15 no.2
• /
• pp.151-169
• /
• 2007

By the environment-friendly(hereafter EF) agricultural policy and toward the safety food of consumers, there is much glowing supply and demand fur EF agricultural products, in Korea. But, in general, EF agricultural products are blown as unique, unreasonable and high price system. This study aims to make clare the main bodies and competition structure in EF agricultural products and the different from the agricultural products. The mail results of this study are summarized as follows. Firstly, farmers and consumers directly participate in the distribution, and the major distributors participate in the market of EF agricultural products after the certification system is got ready. Because EF agricultural products is not dealt and the price system is not built up in agricultural wholesale market. Secondly, the distribution route of EF agricultural products is organized the unified organization by the main bodies such as farmers, consumers co-op, and special distributors. In any step of distribution, the main body of distribution surely deals with the contracted farmers, consumers co-op, and special distributors. Accordingly, it is said that EF agricultural products has the competition structure between the distribution route organized the unified organization rather than between main bodies in the each steps of distribution.

• Journal of Information Technology Services
• /
• v.21 no.5
• /
• pp.15-28
• /
• 2022

Recently, government agencies are actively adopting the platform model as a means of public policy. However, existing studies on the public platform are minimal and have focused on user experiences or the possibility of public usage of the platform model. Now the research concerning building governance structure and utilizing network effects of the platform after adopting the platform model in the public sector is keenly required. This study intended to ignite academic dialogue on the governance of public platforms in the context of digital transformation. This study focused on a case of the 'Special delivery,' a public delivery app established by Gyeonggi-do. In order to analyze the characteristics of the public platform and its governance structure, data were collected from press releases, policy reports, and news articles. Data was analyzed using the frame of Hagui's platform design factors and Ansell & Gash's collaborative governance model. The results of the public platform analyses showed 1) incompleteness in the value trade-off accounting, which was designed for platform business based on general cost-benefit analysis, and 2) a closed governance structure that limits direct participation of diverse user groups(i.e., service provider, customer) in order to enhance providers' utility by preventing customers' excessive online activities. The results of this study provided theoretical and policy implications regarding designing the strategy for accounting for value trade-offs and functioning governance structure for public platforms.