• 한국지구물리탐사학회:학술대회논문집
• /
• 2007.06a
• /
• pp.303-306
• /
• 2007

After Kyoto protocol took effect, many countries are making efforts to reduce $CO_2$ one of effective which is geosequestration. But a percentage of geosequestration in total research budget is very small and the priority order of research also is receded in Korea. As one of efforts to activate the research on geosequestration in field of geophysics, we proposed the plan to build up a measurement system for rock physical properties monitoring during $CO_2$ injection which will function as original technology. The system consists of two part, one of which is a data acquisition system based on seismic and complex resistivity tomographic measurement and the other of which is a tri-axial compressive system to realize the in-situ condition. And also developments of various inversion algorithms are proposed to interpret data qualitatively such as a inversion algorithm for confined cylindrical boundary, a joint inversion algorithm and a 4-D inversion algorithm.

• Proceedings of the SAREK Conference
• /
• 2008.06a
• /
• pp.16-21
• /
• 2008

In order to protect the environment from the refrigerant pollution, the $CO_2$ may be regarded as one of the most attractive alternative refrigerants for an automotive air-conditioning system. Control methods for a $CO_2$ system should be different because of $CO_2$'s unique properties as a refrigerant. Especially, the high-side pressure of a $CO_2$ system should be controlled for the effective operation of the system. High-side pressure algorithms, which were composed of the pressure setpoint algorithm and the pressure setpoint reset algorithm, were developed. Pressure setpoint algorithms, by using a neural network and by using a least square method, were developed and compared. Pressure setpoint reset algorithms, by using a fuzzy logic and by using a proportional logic, were also developed and compared. Simulation results showed that a least square method was more useful than a neural network for the pressure setpoint algorithm. And a proportional logic was more practical than a fuzzy logic for the pressure setpoint reset algorithm.

• The Journal of the Korea Contents Association
• /
• v.5 no.6
• /
• pp.309-318
• /
• 2005

Learners show lower cooperation and responsibility at e-Learning(Electronic Learning) than face-to-face learners in class. Accordingly the LMS(Learning Management System) focus on collaborative learning design in order to promote the learner's interaction. In this paper, the Experience Learning Support System with JXTA-based P2P(Peer-to-Peer) architecture is proposed for an effective collaborative learning and a blended learning. It intends learners to develop a self-leading learning ability and a creative problem-solving ability through experience learning object's sharing. The experimental results described that the proposed system was more effective in an enhancing learner's learning ability and a cooperative learning than existing system.

• Journal of the Korea Society of Computer and Information
• /
• v.13 no.7
• /
• pp.221-229
• /
• 2008

The development of computer and multimedia brought out new technology, that is, virtual reality. Computer simulation adaptation among the technologies of the virtual reality is spreaded into air service, motor vehicle, medical science, sports, education, even fashion industry. This study look into 2-dimensional hair-style computer simulation system which is started to common use nowadays and the 3-dimensional system which is under the development. And this study proposed several problems such as heavy 3D system booth and the low price but low qualified camera in order to commercialize the 3D system. This study also suggest several alternative, for instance, the change from object photography method to panoramic photography method, the substitute by middle or high end and high qualified camera.

• KIISE Transactions on Computing Practices
• /
• v.21 no.1
• /
• pp.58-63
• /
• 2015

In this work, we present a novel fountain code-based hybrid P2P storage system that combines cloud storage with P2P storage. The proposed hybrid storage system minimizes data transmission time while guaranteeing high data retrieval and data privacy. In order to guarantee data privacy and storage efficiency, the user transmits encoded data after performing fountain code-based encoding. Also, the proposed algorithm guarantees the user's data retrieval by storing the data while considering each peer's survival probability. The simulation results show that the proposed algorithm enables fast completion of the upload transmission while satisfying the required data retrieval and supporting the privacy of user data under the system parameters.

• International Commerce and Information Review
• /
• v.8 no.2
• /
• pp.141-162
• /
• 2006

This paper focuses on the phenomenon that international payment system is essential as reverse action of delivery or supply of digital goods in global transactions. In order to impose the customs duties on imported goods in global on-line transactions, the imposition of tariff by tracing the payment process when business transaction is occurring is recommended. The purpose of this study is to review the countermeasures for effective tariff imposition system by using the model of the main payment tools in global transactions. Some models reviewed in this paper are as follows : i) a model of withholding taxes at the source by the credit company ii) a model of self declaration by the importer iii)a model of registering by overseas company iv) a model of negotiating after the taxation at the export country This study is different from existing preceding research at the point of view of presenting 4 models and doing appraisal by each model. It should be done more in depth and various study on the model of the tariff imposition system about the models reviewed at this paper. Systematic and reasonable alternatives which are actually adoptable at the system should also be studied and examined carefully. Because it is required that tariff imposition system on the digital goods should be harmonized with that of traditional business in order to obtain effectiveness and rightfulness, and especially, in order to get justness for the imposition a tariff on digital goods, the process of tax imposition should be predictable and be sure to get the fairness by enhancing the equilibrium, impartiality and transparency.

• The Journal of the Society of Korean Medicine Diagnostics
• /
• v.20 no.2
• /
• pp.51-65
• /
• 2016

Objectives This study was conducted to suggest a standard operating procedure (SOP) in order to improve the reliability of tongue-image analysis system. Methods An affecting-factors list was made, which may affect the diagnostic parameters of the tongue-image analysis system. They were sub-classified into two groups: controllable and uncontrollable. Only the controllable factors, which could affect the results and easily set-up, were included into the SOP draft. Affecting factors control experiment was performed to investigate the effects of controllable factors, whose influence on diagnostic parameters of the tongue-image analysis system is ambiguous: rehearsal for tongue extrusion; alignment of camera axis; and presentation of a guideline. Three subjects volunteered for this experiment. Each of three variables was implemented twice in a random order by two operators on the subjects. Finally, 96 tongue images obtained in the aggregate. The diagnostic parameter set as a primary outcome in this experiment was the percentage of tongue coating. Results All of the control variables were not significant in both operators; however, the presentation of a guideline was relatively more affect than two other variables. Interaction effects among the variables were also insignificant. Therefore, the presentation of a guideline was included in the final SOP and the other variables were not included. Conclusions We suggested the SOP which could be used for both experimenter and subject. Moreover, Each of the SOPs applied to various types of tongue-image analysis system should be developed in order to improve the reliability.

• Journal of the Korean Ceramic Society
• /
• v.31 no.12
• /
• pp.1437-1442
• /
• 1994

Self propagating synthesis and thermal explosion of combustion reactions were applied to Al/K2Cr2O7/Al2O3 system as the first stage for a production of magnesia-chromium refractory. Several factors related to products made by two combustion reactions were considered and properties of products were characterised. Two processes were required to preheat upto at least 80$0^{\circ}C$ for the thermal explosion and the self propagating synthesis. These processes were so violent and explosive that alumina as diluent was added to the system in order to absorb the reaction heat and reduce the reaction rate. The products consisted of crystal phases of KAl5O8, Cr2O3, Al2O3, K2CrO4, and K2Al2O4.3H2O. The amount of KAl5O8 and K2Al2O4.3H2O crystal phases of products were decreased with further addition of alumina.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1997.11a
• /
• pp.39-43
• /
• 1997

Effects of B$_2$O$_3$ addition in the Li$_2$O-MgO-MgF$_2$-SiO$_2$g1ass system were investigated in order to make glass-ceramics for low temperature firing substrate. Base glass was made by melting at 145$0^{\circ}C$ . This glass was analyzed by THA and DTA to settle nucleation and crystallization temperature. After crystallization. crystal phase and microstructure were absorvated by XRD and SEM. Glass powders were made by water swelling method. Average particle size was 5.44${\mu}{\textrm}{m}$

• The KIPS Transactions:PartC
• /
• v.11C no.6 s.95
• /
• pp.835-842
• /
• 2004

In this paper, we have analyzed the MC-DS/CDMA system with input signal synchronized completely through adjustment of the gain in the PLL loop, by using the hybrid SC/MRC-(2/3) technique, which is said to one of the optimal diversity techniques under the multi-path fading environment, assuming that phase error is defined to the phase difference between the received signal from the multi-path and the reference signal in the PLL of the receiver. Also, assuming that the regarded radio channel model for the mobile communication is subject to the Nakagami-m fading channel, we have developed the expressions and performed the simulation under the consideration of various factor, in the MC/DS-CDMA system with the hybrid SC.MRC-(2/3) diversity method, such as the Nakagami fading index(m), $the\;number\;of\;paths\;(L_p),$ the number of hybrid SC.MRC-(2/3) $diversity\;branches\;(L,\;L_c),$ the number of users (K), the number of subcarriers (U), and the gain in the PLL loop. As a result of the simulation, it has been confirmed that the performance improvement of the system can be achieved by adjusting properly the PLL loop in order for the MC/DS-CDMA system with the hybrid SC/MRC-(2/3) diversity method to receive a fully synchronized signal. And the value of the gain in the PLL loop should exceed 7dB in order for the system to receive the signal with prefect synchronization, even though there might be a slight difference according to the values of the fading index and the spread processing gain of the subcarrier.