• Journal of Digital Convergence
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• v.7 no.4
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• pp.81-90
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• 2009

SaaS (Software as a Service) provides software in the form of service via internet rather than software package. Thus a large number of users could use the service of new type of software service as long as they connect to internet. SaaS, as a delivery model attracted in the software industry, grows with impelling force. SaaS has been adopted as an information spreading strategy of small and medium corporate so that its effect has been recognized in both academic and practical areas. However, there are not much researches about it because SaaS is still in the introductory stage. This study focused on the success model of SaaS to find out the factors that affect usability and the satisfaction of users. The sample is based on the on-line survey for the 549 government officials who are using SaaS. At last, the number of the employed answers are 157 after unqualified ones are removed. The result shows that Security, Service quality, Price and System Integration significantly affect the usefulness and the satisfactions of users.

• Korean Journal of Computational Design and Engineering
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• v.18 no.6
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• pp.399-406
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• 2013

This paper describes a new simulation technique for advection-diffusion phenomena over the sea surface using the lattice Boltzmann method (LBM), capable of predicting oil dispersion from tankers. The LBM is used to solve the pollutant transport problem within the framework of the ocean environment. The sea space is represented by the lattices, where each lattice has the information on oil transportation. Since dispersed oils (i.e., oil droplets) at sea are transported by convection due to waves, buoyancy, and turbulent diffusion, the conservation of mass and many physical oil transport rules were used in the prediction model. Since the LBM is modeled using the uniform lattices and simple rules, it can be easily accelerated by the parallel mechanism, for example, GPU-accelerated method. The proposed model using the LBM is used to simulate a simple pollution event with the oil pollutants of 10,000 kL. The simulation results indicate that the LBM method accelerated with the GPU is 6 times faster than that without the GPU.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.3
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• pp.234-238
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• 2014

Multichip packaging was achieved the best solution to significantly reduce thermal resistance at the same time, to increase luminance intensity in LEDs packaging application. For the packaging, thermal spreading resistance is an important parameter to get influence the total thermal performance of LEDs. In this study, silicon-based multichip light emitting diodes (LEDs) packaged module has been examined for thermal characteristics in several parameters. Compared to the general conventional single LED packaged chip module, multichip LED packaged module has many advantages of low cost, low density, small size, and low thermal resistance. This analyzed module is comprised of multichip LED array, which consists of 32 LED packaged chips with supplement power of 0.2 W at every single chip. To realize the extent of thermal distribution, the computer-aided design model of 6.4 W Si-based multichip LED module was designed and was performed by the simulation basis of actual fabrication flow. The impact of thermal distribution is analyzed in alternative ways both optimizing numbers of fins and the thickness of that heatsink. In addition, a thermal resistance model was designed and derived from analytical theory. The optimum simulation results satisfies the expectations of the design goal and the measurement of IR camera results. tart after striking space key 2 times.

• The Korea Journal of Herbology
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• v.21 no.1
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• pp.9-15
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• 2006

Objectives : Lonicerae Flos has been known as a useful plant with anti-inflammatory, antioxidative and immunosuppressive activity. To evaluate anti-inflammatory effect of Lonicerae Flos, we treated Lonicerae Flos-skin in animal model system induced contact hypersensitivity. Methods : Contact hypersensitivity, a local inflammatory response of the skin, was induced by spreading the right ear of BALB/c mouse with 1% DNCB. Lonicerae Flos-skin was prepared by dissolving 1% water extract of Lonicerae Flos in skin vehicle and treated everyday for 2 weeks on the right ear. Results : Lonicerae Flos-skin significantly reduced a mouse ear thickness swelled by 1% of DNCB treatment compared with skin vehicle-treated control group. Lonicerae Flos-skin also reduced IgG and IgE in serum obtained from blood of 1% DNCB-treated mouse. Conclusion : These results showed that Lonicerae Flos-skin could be used as a pharmaceutical material with antiinflammatory effects by reducing IgG and IgE in contact hypersensitivity mouse model by DNCB.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.11
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• pp.1417-1423
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• 1999

Distribution system can experience the diverse events instantly and permanently. Also, it can experience high impedance fault or line drop under unbalanced situation, Accordingly, it is difficulty to identify the fault location because that data collected from distribution SCADA system may include uncertainty. This paper proposes an expert system, which can infer the faulted location the quickly and exactly for the diverse events in the distribution system. The expert system utilizes distribution SCADA function and collected data, especially, the monitoring mechanism for the normal open position switches is adopted newly in order to recognize the fault type exactly. Also, automated fault location diagnosis strategy is developed in order to minimize the spreading effect of fault obtained from the error of the system operator. The proposed strategy is implemented in C language. Especially, in order to prove the effectiveness of proposed expert system, the several scenario is simulated for the given model system. The real feeders are selected as model system for the simulation.

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.61-65
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• 2008

In this paper, research into the model of u-Culture and Tourism contents business using RFID and technologies of wireline and wireless communication. It suggests u-Culture and Tourism system solution which is making an attempt at connecting technology and culture with meeting a cultural paradigm change in a variety of fields, as a digital life is spreading. Also, It confirmed the possibility as reproducing the contents of each scenario after composing the contents system of culture and tourism using RFID applied technology. And It suggests a business model in relation to new u-Culture and Tourism contents using RFID applied technology.

• Journal of Korea Water Resources Association
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• v.36 no.1
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• pp.75-85
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• 2003

Urban rainfall-runoff procedures are more complex than the agricultural procedures due to the spreading and development of town. And the applications of theses models are more difficult due to the change of real basins. In this study, I applied SWMM and Expert System to get runoff characteristics of an urbanized basin. Noen in Daejeon is selected as a study basin. Real basin data of facilities, rainfall, runoff, and various rainfall intensity equations are used. An Expert System is used to get the parameters of this model. These results can be applied to analyze the reaction tendencies of the urban basin with the time distributions of design rainfall and the urbanization.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.1
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• pp.364-379
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• 2019

Wave-induced ship motion and load responses are usually investigated on the assumption that the incident waves are long-crested. The realistic sea waves are however short-crested irregular waves. Real practice reveals that the ship motion and load responses induced by short-crested waves are different from those induced by long-crested waves. This paper aims to conduct a comprehensive study on ship motions and loads in different wave fields. For this purpose, comparative studies by small-scale model towing tank test and large-scale model sea trial are conducted to experimentally identify the difference between ship motions and loads in long-crested and short-crested irregular waves. Moreover, the influences of directional spreading function of short-crested waves on ship motions and loads are analyzed by numerical seakeeping calculation. The results and conclusions obtained from this study are of great significance for the further extrapolation and estimation of ship motions and loads in short-crested waves based on long-crested wave response results.

• Journal of the Korean Society of Propulsion Engineers
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• v.24 no.4
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• pp.25-32
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• 2020

A numerical study on combustion instabilities in a model combustor was conducted with various momentum flux ratios. Five ratios are calculated based on an actual operating condition of rocket engine. As momentum flux ratio increases, the spreading angle on the injector outlet decreases. And, as increase of axial momentum flux, pressure fluctuation decreases inside the combustor. By using dynamic mode decomposition method, the acoustic modes inside the combustor are identified. Combustion stabilities are analyzed by comparing the damping coefficient of the 2^nd longitudinal mode.

• Electronics and Telecommunications Trends
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• v.36 no.4
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• pp.48-60
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• 2021

Following the global air-traffic market growth outlook, urgency of technical development is needed in responding to changes in the international air-traffic management paradigm and to prepare technology securing and spreading strategies, which are consistent with systematic aviation weather service policies and evolution direction. Although air traffic has decreased significantly due to COVID-19, normalcy is expected from 2024, as announced by IATA. According to the future air transportation market outlook and development trends of related technologies, Korea has established and implementing the next-generation air transportation system construction plan(NARAE) to secure international competitiveness and leadership in the future. Therefore, this paper describes the technical, economic background and requirements of numerical model-based aviation weather R&D projects for successful implementation of domestic NARAE plans and providing aviation safety and air traffic service efficiency. Furthermore, we proposed numerical-model-based technology development content, strategies and detailed load-map.