• International Commerce and Information Review
• /
• v.5 no.1
• /
• pp.39-59
• /
• 2003

The purpose of this paper is to examine the possibility of whether B2B e-marketplaces continue to grow. There are numerous barriers to the growth of e-marketplace, but certain key factors can push e-marketplaces beyond these obstacles. In the stage of generating traffic, it is essential to find a vertical area to attract buyers and sellers which can generate B2B transaction through e-marketplace. Generating traffic is possible only for e-marketplaces established by those who have vertical knowledges and strong off-line relationship in the vertical areas. In the stage of concentrating traffic, more attention should be given to reach critical mass and to increase transaction through e-marketplace. Currently, there seems to be a tendency that having major buyers as members of a e-marketplace is an true factor for the successful e-marketplace. Finally, to attain the locking traffic, e-marketplace needs to have the ability to generate revenue through B2B transaction. What we have learn from this study is that having the software-technology is not a sufficient condition to successfully operate B2B e-marketplace. It is important for e-marketplace to attract major players in order to increase B2B transaction, and also to make profit by them.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.24 no.2
• /
• pp.77-86
• /
• 2020

Nonlinear static analysis and preliminary evaluation were performed in this study to evaluate the seismic performance of unreinforced masonry buildings subjected to various soil conditions based on the revised Korean Building Code. Preliminary evaluation scores and nonlinear static analyses indicated that all buildings were susceptible to collapse and did not reach their target performance. Therefore, retrofit of those building models was carried out through a systematic procedure to determine areas to be strengthened. It was possible to make most building models satisfy performance objectives through the reinforcement alone of damaged external shear walls. However, the application of a preliminary evaluation procedure to retrofit design was found to be too conservative because all the retrofitted building models verified with nonlinear static analysis failed to satisfy performance objectives. Therefore, it is possible to economically retrofit unreinforced masonry buildings through the fortification of external walls if a simple evaluation procedure that can efficiently specify vulnerable parts is developed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.16 no.6
• /
• pp.599-607
• /
• 2004

The purpose of this study is to reevaluate the performance of Hanji as an architectural material. Hanji has good things in controlling indoor space comfortably. Particularly, ability of controlling humidity of Hanji affects indoor space comfort and human health. The major focuses of this experimental research are (1) how much of water vapor passes through Hanji, (2) how much of water vapor is absorbed into Hanji. In the first case, indoor humidity is higher than outdoor humidity. In this case, approximately 38 g of water vapor passes through Hanji 1, genarally utilized in window paper (Changhoji), per square meter in one hour. And approximately 4 g of water vapor is absorbed into Hanji 2, genarally utilized in wallpaper, per square meter. In the second case, outdoor humidity is higher than indoor humidity. In this case, Hanji passes water vapor to inner space at first, but when indoor relative humidity reach approximately 66%, although outdoor humidity is higher than indoor humidity, water vapor doesn't pass through Hanji. If Hanji is utilized in window material and wallpaper, indoor space is maintained comfortably without mechanical devices in humidity control.

• Journal of Pharmaceutical Investigation
• /
• v.41 no.6
• /
• pp.337-345
• /
• 2011

The objective of this work is to investigate the effect of chemical enhancer and current on the flux of donepezil hydrochloride (DH) through skin. Ethanol and N-methyl pyrrolidone (NMP) were used as chemical enhancers in combination with iontophoresis. We also have studied the effect of pH on flux and evaluated the role of electroosmosis. In vitro flux study was performed at $33^{\circ}C$, using side-by-side diffusion cell and full thickness hairless mouse skin. Passive flux of DH without enhancer was very small. As the concentration of enhancer increased, passive flux increased. After current application, flux increased markedly and the time to reach maximum decreased. Without enhancer, maximum flux was about 50 fold larger than that obtained without current. These results indicate that electromigration is playing a major role for the transport. As the enhancer concentration increased, flux also increased. NMP and ethanol increased not only the passive delivery, but also the iontophoretic delivery. Flux results indicate that ethanol has better ability than NMP in enhancing the transport of DH. The magnitudes of increase in flux by these enhancers indicate that there is a large synergistic effect in flux enhancement. Flux results from pH study showed that electroosmotic flow is reversed at low pH and the flux is hindered. These results provided some information on the flux enhancing ability of ethanol and NMP in combination with iontophoresis. The data also provided some mechanistic insights into the role of electromigration and electroosmosis on flux through skin.

• Journal of Internet Computing and Services
• /
• v.5 no.1
• /
• pp.33-39
• /
• 2004

In this paper, so that government official in target extent of relevant shame capacitates CMM measuring achievement result by each process as quantitative because do standard, repeat and achieves gap analysis and estimation solidify knowledge management of information base enabling "Quality control, production management, cost control, integral management of knowledge", Solidify customer service through "high-quality, differentiation" of information. Establish administration and supervision item to reach 4 steps level in information ability measurement in formation to prove business efficiency through process optimization and improves formation maturity through voluntary effort of formation continuously. Suggested model who analyze and evaluates application in domestic SI specialty company.I specialty company.

• The Bulletin of The Korean Astronomical Society
• /
• v.44 no.1
• /
• pp.49.1-49.1
• /
• 2019

Giant radio relics in the outskirts of galaxy clusters have been observed and they are interpreted as synchrotron emission from relativistic electrons accelerated via diffusive shock acceleration (DSA) in weak shocks of Ms < 3.0. In the DSA theory, the particle momentum should be greater than a few times the momentum of thermal protons to cross the shock transition and participate in the Fermi acceleration process. In the equilibrium, the momentum of thermal electrons is much smaller than the momentum of thermal protons, so electrons need to be pre-accelerated before they can go through DSA. To investigate such electron injection process, we study the electron pre-acceleration in weak quasi-perpendicular shocks (Ms = 2.0 - 3.0) in an ICM plasma (kT = 8.6 keV, beta = 100) through 2D particle-in-cell simulations. It is known that in quasi-perpendicular shocks, a substantial fraction of electrons could be reflected upstream, gain energy via shock drift acceleration (SDA), and generate oblique waves via the electron firehose instability (EFI), leading the energization of electrons through wave-particle interactions. We find that such kinetic processes are effective only in supercritical shocks above a critical Mach number, $Ms{\ast}{\sim}2.3$. In addition, even in shocks with Ms > 2.3, energized electrons may not reach high energies to be injected to DSA, because the oblique EFI alone fails to generate long-wavelength waves. Our results should have implications for the origin and nature of radio relics.

• International Journal of Advanced Culture Technology
• /
• v.11 no.3
• /
• pp.327-331
• /
• 2023

This paper proposes a tourist destination recommendation application that combines a chatbot and a recommendation system. The data to be entered into the chatbot was through big data on social media. Through TEXTOM, a total of 22,701 data were collected over a one-year period from January 2022 to January 2023. Non-terms that interfere with analysis were removed through the data purification process. Using refined data, network visualization and CONCOR analysis were used to identify the information users want to obtain about travel to Jeju Island, and categories for each cluster were organized. The content was intuitively organized so that even those who approached it for the first time could easily use it, reducing the difficulty of operating the application. In this paper, users can select their own preferences and receive information. In addition, a tool called a chatbot allows users to focus more on the process of acquiring information by gaining a sense of reality while operating the application. This suggests an application that can reach the purpose of the curator by affecting the user's desire to visit tourist attractions.

• Journal of Korea Water Resources Association
• /
• v.37 no.12
• /
• pp.1043-1054
• /
• 2004

An unsteady flow model for channel network including various internal boundaries if developed. It is a multiply-connected network model based on the Preissmann's four-point scheme and the Newton-Raphson method, where looped double-sweep algorithm is used. The model is capable of simulating flow through hydraulic structures such as dams and submerged weirs. It can also simulate automatic reservoir operation method (Auto ROM) for flood control, that is to maintain a target water level, by incorporating the strategy to the unsteady flow model as internal boundary condition. The model is applied to the Han River system that includes the downstream reaches of Choongju dam and Hwacheon dam as well as the downstream reach of the Paldang dam. Roughness coefficient for the downstream reach of Choongju dam is estimated. Automatic ROM is presumed for the Paldang, Chungpyung, Euiam, and Choonchun dams. The model is tested using historical flood records, and the flood control strategy is successfully simulated.

• Journal of Korean Society on Water Environment
• /
• v.28 no.1
• /
• pp.10-17
• /
• 2012

The middle and lower reaches of the Kum River system become stagnant in dry seasons with florishing of phytoplankton. In this study primary productivity of phytoplankton were measured by the C-14 uptake method and the P-I model method at seven main stream sites of the Kum River from the Daechung Dam outet to the river mouth. Nutrients (TN, TP, DIP, TIN) concentrations were measured in the mainstream and tributaries and compared with the variation of assimilation number. The range of primary productivity was $40{\sim}4,558mgC{\cdot}m^{-2}{\cdot}day^{-1}$ and it was higher than those of lentic ecosystems in Korea. Average TN and TP were $4.1mgN{\cdot}L^{-1}$, $70.6mgP{\cdot}m^{-3}$, respectively. Tributaries showed higher nutrient concentrations than the main stream. After two major tributaries merged with the discharging water of the Daechung Dam phyotplankton biomass and productivity increased drastically and remained at the similar eutrophic level through the downstream reach to the river mouth. Both dissolved phosphorus and nitrogen concentrations showed positive correlation with assimilation number of phytoplankton. In conclusion phytoplankton productivity is at the level of eutrophic water and it was higher than usual lentic habitats. Nutrient concentrations are critical factors in controlling productivity in the lower reach of the Kum River.

• Journal of the Korean School Mathematics Society
• /
• v.1 no.1
• /
• pp.97-109
• /
• 1998

The activities of teaching and learning are to try to reach the lesson object most closely in many ways. Considering that the lesson objects are to get the principle or law of a concept, to acquire the mathematical function, to master it through repeated exercises and to solve mathematical problems, we need many ways to reach such objects. Among the many ways, we can first think of one: the students will learn with curiosity and according to their own ability or advancing level in learning when teachers study and prepare necessary contents enough in advance by using computers, showing the right program to learners' needs. For example, defining definite integral by measuration by parts will help understand measuration by parts well and know the meaning of definite integral correctly, In teaching and learning by the use of this program, the educational effects are expected as follows. 1. It is thought that this program will stimulate the desire for and interest in learning because it used animation and acoustic effect. And voluntary and positive thinking activity will be shown. 2. It is expected that the conviction of formulas will be got and the concept of definite integral will be remembered firmly by showing how to measure the width of circle with the use of measuration by parts in various other ways instead of the ways used at present. 3. It is expected that students will feel the pleasure of mathematics in life when they recognize mathematical facts scattered really in our life rather than mathematical difficulties. 4. It is expected that the repeated review of programs already designed will remove the fear of incomplete parts and help review again. 5. It is certain that positive attitude in life will be formed as teacher-centered class is changed into learner-centered class and unwilling study is changed into self-oriented study. However, I think this program is insufficient for humanbeing-centered education given directly in contact with students on the ground of the variety in mathematical education and applications in many ways. And mechanically inhuman computers leave some solutions to be desired