• Electrical & Electronic Materials
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• v.7 no.4
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• pp.317-324
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• 1994

In this study, new preparation method of LiCoO$_{2}$ was applied to develop cathode active material for Li rechargeable cell, and followed by X-ray diffraction analysis, electrochemical properties and initial charge/discharge characteristics as function of current density. HC8A72- and CC9A24-LiCoO$_{2}$ were prepared by heating treatment of the mixture of LiOH H$_{2}$O/CoCO$_{3}$(1:1 mole ratio) and the mixture of Li$_{2}$CO$_{3}$/CoCO$_{3}$(1:2 mole ratio) at 850 and 900.deg. C, respectively. Two prepared LiCoO$_{2}$s were identified as same structure by X-ray diffraction analysis. a and c lattice constant were 2.816.angs. and 14.046.angs., respectively. The electrochemical potential of CFM-LiCoO$_{2}$(Cyprus Foote Mineral Co.'s product), HC8A72-LiCoO$_{2}$ and CC9A24 LiCoO$_{2}$ electrode were approximately between 3.32V and 3.42V vs. Li/Li reference electrode. Stable cycling behavior was obtained during the cyclic voltammetry of LiCoO$_{2}$ electrode. According as scan rate increases, cathodic capacity decreases, but redox coulombic efficiency was about 100% at potential range between 3.6V and 4.2V vs. Li/Li reference electrode. Cathodic capacity of HC8A72-LiCoO$_{2}$ was 32% higher than that of CFM-LiCoO$_{2}$ and that of CC9A24-LiCoO$_{2}$ was 47% lower than that of CFM-LiCoO$_{2}$ at 130th cycle in the condition of lmV/sec scan rate. Constant cur-rent charge/discharge characteristics of LiCoO$_{2}$/Li cell showed increasing Ah efficiency with initial charge/discharge cycle. Specific discharge capacities of CFM and HC8A72-LiCoO$_{2}$ cathode active materials were about 93mAh/g correspondent to 34% of theretical value, 110mAh/g correspondent to 40% of theretical value, respectively. In the view of reversibility, HC8A72-LiCoO$_{2}$ was also more excellent than CFM- and CC9A24-LiCoO$_{2}$.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.5
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• pp.159-168
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• 2010

This study investigates the relationships between the maximum freshwater pumping discharge and hydraulic properties of coastal aquifer using a laboratory model. The experiment performed the fresh pumping test in various locations near the saltwedge induced by saltwater intrusion to freshwater over aquifer characteristics of hydraulic conductivity, salinity, and ground surface slope. Saltwater pumping also tested to protest saltwater intrusion to the excessively discharging freshwater well. The maximum freshwater discharges were achieved, and then the optimum saltwater discharges were measured. It is found that greater hydraulic conductivity and ground surface slope produced greater the maximum freshwater pumping discharge. Salinity gave less impact on the pumping discharge relatively. Higher freshwater discharge was found at higher hydraulic conductivity and steeper ground surface slope. The optimum saltwater discharge required 14% more pumping rate than the maximum freshwater discharge to keep saltwater intrusion to the freshwater pumping well. Pumping well located closer to salt-wedge profile promoted less freshwater pumping discharge. Therefore, pumping well location, hydraulic conductivity, ground surface slope, and salinity should be taken into account in freshwater pumping in coastal aquifer.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.12
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• pp.6159-6166
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• 2012

A discharge measurement is difficult in flood season which is especially important in the water resources field and the continuous discharge measurement for all rivers is impossible on the present system. So, the stage-discharge curve has been used for a long time to produce discharge data of rivers. However, there has been problems from a reliability angle due to the fact that this method uses only stage-discharge relationship, although the stage-discharge curve has the convenience. Therefore, a new mean velocity equation was derived by using Chiu's 2D velocity formula of the entropy concept in this paper. The derived equation reflected hydraulic characteristics such as the depth, gravity acceleration, hydraulic radius, energy slope, kinematic coefficient of viscosity, etc. and estimated also a maximum velocity. In addition, this method verified the relationship between a mean and maximum velocity and estimates an equilibrium state ${\phi}(M)$ well presenting properties of a river cross section as the results. The mean velocity was estimated by using the equilibrium state ${\phi}(M)$, and then the discharge was estimated. To prove this equation to be accurate, the comparison between the measured and estimated discharge is conducted by using the measured laboratory data in the unsteady condition flow showing loop state and the results are consistent. If this study is constantly carried out by using various laboratory and river data, this method will be widely utilized in water resources field.

• Journal of the Korean GEO-environmental Society
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• v.12 no.10
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• pp.39-49
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• 2011

Recently PBD method, one of acceleration of consolidation methods is used in the soft ground to shorten consolidation time for fast settlement during construction. It is economical and easy to work. Discharge capacity of PBD is sensitive in proportion to thickness of soft ground layer, and drainage of PBD declines due to disturbance effect in surrounding ground by mandrel used for vertical drainage setting and setting machines and type. Also, deviation of discharge capacity is large according to ground condition, construction condition and soil properties. In addition, when embankment loading is not conducted instantly after PBD setting due to rain or lack of embankment material supply, it causes leaving period problems. But cause and analysis of those problems for discharge capacity is lack. So, in this test, ground improvement and discharge capacity is investigated by implementing composite discharge capacity test for analysis of an effect factor of PBD discharge capacity with leaving period. After fixing the vertical drain on a cylindrical cylinder, put churned sample into the cylinder. Then leave 0day, 30day, 60day and 90day. And then, load following the loading step of 30, 70 and 120kPa using a pressure device. As a result, the longer leaving period, discharge capacity is reduced. It is caused by a decrease of discharge area caused by creep transformation moisture absorption of PBD filter after long leaving period.

• Journal of Korean Medical classics
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• v.33 no.1
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• pp.149-158
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• 2020

Objectives : This study aims to examine the exterior relief method through pungent-cool properties in comparison to pungent-warm properties historically, to understand the meaning of 'exterior relief through pungent-cool' more thoroughly. Methods : Contents mentioning the treatment method directly were examined historically, then analyzed. Results & Conclusions : The method to relieve the exterior through pungent-cool properties has developed by overcoming the limitations of the method to relieve the exterior through pungent-warm properties since it was first established in 『Shanghanzabinglun』(『傷寒雜病論』). The term 'relief of the exterior through pungent-coolness'(辛凉解表) was first mentioned in the Ming period, referring to weak level of perspiration. Yetianshi(葉天士) explained it as communicating Weiqi(衛氣) using pungent-cool medicinals for heat to discharge through the exterior, resulting in mild sweating. In 『Wenbingtiaobian』(『溫病條辨』) the term 'to relieve the flesh'(解肌) refers to both mild sweating through pungent-warm medicinals and the opening of the exterior through pungent-cool medicinals for pathogenic qi to exit, resulting in sweating. If the exterior relief of the pungent-warm medicinals happens through the warm Yang qi(陽氣) stimulated the inner Yin fluids(陰液) to discharge as sweat, that through pungent-cool medicinals relieves stagnation in the exterior, opening up a way for the pathogenic heat to exit. From the perspective of the main therapeutic mechanism for pungent-cool medicinals to be its coolness relieving heat, the term 'exterior relief through pungent-coolness' becomes erroneous. For the 'exterior relief through pungent-coolness' category to be valid, the meaning of 'exterior relief' needs to be expanded to include not only stimulated sweating but the treatment process that could result in sweating.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.6 no.1
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• pp.84-91
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• 1997

In producing moldings by using an injection mold, several variables such as the metal mold and the condition of injection molding should be selected properly in order to obtain good quality of moldings. In this study, focussed are the mechanical properties of injection moldings, since many researches on injection have been focussed mainly on the molding quality, injection pressure, and bulk temperature but the properties of injection moldings have not been studied extensively. The mechanical properties of present injection moldings can be improved simply by changing the molding material and the injection conditon without changind the metal mold. To have the final products meet the specified molding quality and mechanical properties at the same time, the bulk temperature of injection, pressure variation, volumetric shrinkage, stress, and cooling should be analized by CAE(computer aided engineering) after injection mold design. In this paper, the effects of dischare condition on mechanical properties of injection moldings are studied by testing the moldings which are injected by varying injection conditions.

• Proceedings of the KIEE Conference
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• 1999.07e
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• pp.2426-2427
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• 1999

This study is the result of determination and analysis to draw out six schools in order to research into the lighting properties of the school Almost schools are supported and used large area by a high brightness lamp, for example high pressure mercury discharge lamp etc. The gymnasium of A, B, E schools have a good capacity of the illuminance.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.740-743
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• 2009

In this paper we proposed a new electrode design to get an enhanced luminous efficiency in AC PDP. The width and shape of the TTO electrode were varied, and the electro-optical properties such as luminance, power consumption, luminous efficiency were estimated with the variation of frequency, duty ratio and applied voltage. The discharge characteristics were investigated to explain the effect of the new electrode structure on the electro-optical properties.

• Journal of the Korean Ceramic Society
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• v.42 no.5 s.276
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• pp.352-358
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• 2005

By calcining at $750^{\circ}C$ for 30 h in $O_2$ stream after milling, $LiNi_{1-y}M_yO_2(M=Zn^{2+},\;Al^{3+}$, and $Ti^{4+}$, y = 0.005, 0.01, 0.025, 0.05, and 0.1) were synthesized and their electrochemical properties were investigated. All the samples had R3m structure. $LiNi_{1-y}Zn_yO_2$ (y = 0.025, 0.05, and 0.1) contained ZnO anuor $Li_2ZnO_2$ as impurities. Among the samples substituted with the same element, the samples with relatively large value of $I_{003}/I_{104}$ and the smallest R-factor had the largest first discharge capacity and good cycling performance. $LiNi_{0.975}A1_{0.025}O_2$ had the largest first discharge capacity (172.5 mAh/g) and good cycling performance (about $89.4\%$ of the first discharge capacity at the 20th cycle). This sample had the largest value of $I_{003}/I_{104}$ and the smallest R-factor among all the samples. In addition, the particles of this sample were finer and their size was more homogeneous than the other samples. $LiNi_{0.95}A1_{0.05}O_2$ had relatively large first discharge capacity 150.4 mAh/g and good cycling performance.

• Proceedings of the Korean Ceranic Society Conference
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• 2000.04a
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• pp.81.1-81.1
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• 2000