• The Journal of Fisheries Business Administration
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• v.42 no.3
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• pp.79-93
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• 2011

Water temperature of Oliver flounder farm affects Oliver flounder growth and mortality rate. In laboratory experimental tanks, optimal water temperature was $22.5^{\circ}C$($21{\sim}24^{\circ}C$) and cultivatable water temperature was $12{\sim}28^{\circ}C$. The purpose of this study is to identify applicable and useful water temperature of Oliver flounder farm in case of actual farming. The data applied in the analysis was collected from Jeju island. In the study, various analytical methods including productivity analysis, regression analysis, statistical analysis were conducted for 13 Oliver flounder culture farms. The result of analysis can be summarized as follows : First, growth rate on the Oliver flounder culture farms was related to mean of water temperature, variation of water temperature and low water temperature. Second, survival rate on the Oliver flounder culture farms was related to mean of water temperature. In case of including Oliver flounder stocking density, defined as the surface area of Oliver flounder per $m^2$ of water surface area, survival rate strongly related to mean of water temperature, variation of water temperature, cultivating capability and stocking density. Third, production weight per $m^2$ of water surface area was strongly related to mean of water temperature, low water temperature and cultivating capability. Growth rate and survival rate was analyzed into mediate variable character.

• KEPCO Journal on Electric Power and Energy
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• v.2 no.3
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• pp.425-431
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• 2016

Supply Capability of the generator, if the maximum demand occurs, refers to the maximum power that can be stably supplied and it is possible to maintain stable power supply to be greater than actual load. However, unexpected power demand and reduction in supply Capability due to stop of unexpected generator in operation can temporarily make a big chaos in power system. In fact, due to a lack of power supply Capability in the country, enforced emergency load adjustment to the September 15, 2011, the circulation power outage has occurred in several cities. As the result, interrupted operation of the elevator and stopped hospital medical equipment led to a great deal of trouble to people's lives, causing a social problem. At that time, it was found that a failed frequency control because of smaller actual supply Capability than that of predicted. The difference was about 1,170 MW with Gas turbine power plant. By accurately calculating the generator supply capability, we can not only grasp the power reserve rate, but also correspond to the time of power supply instability.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.353-354
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• 2006

This work describes the effect of binders, such as carboxymethylcellulose (CMC), CMC+Polytetrafluoroethylene (PTFE) and PTFE, on the electrochemical and mechanical properties of activated carbon-electrode for electric double layer capacitor. The cell capacitors using the electrode bound with binary binder composed of CMC and PTFE, especially m composition CMC ; PTFE = 60 : 40 wt %, has exhibited the better rate capability and the lower internal resistance than those of the cell capacitor with CMC. On the other hand, the sheet type electrode kneaded with PTFE was bonded with conductive adhesive on Al foil. This cell capacitor using the electrode with PTFE exhibited the best mechanical properties and rate capability compared to the CMC and CMC+PTFE one These behaviors could be explained by the well-developed network structure of PTFE fibrils during the kneading process.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.12
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• pp.1167-1171
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• 2006

This work describes the effect of binders, such as carboxymethylcellulose (CMC), CMC+ Polytetrafluoroethylene (PTFE) and PTFE, on the electrochemical and mechanical properties of activated carbon-electrode for electric double layer capacitor. The cell capacitors using the electrode bound with binary binder composed of CMC and PTFE, especially in composition CMC PTFE = 60 : 40 wt.%, has better rate capability and the lower internal resistance than those of the cell capacitor with CMC. On the other hand, the sheet type electrode kneaded with PTFE was bonded with conductive adhesive on Al foil. This cell capacitor using the electrode with PTFE exhibited the best mechanical properties and rate capability compared to the CMC and CMC+PTFE one. These behaviors could be explained by the well-developed network structure of PTFE fibrils doting the kneading process.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.9
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• pp.973-978
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• 2004

This work describes the effect of conducting materials on the electrochemical performances of electric double layer capacitor. Three kinds of Carbon black, such as Acethylene Black, Super P Black, Ketjen black supplied by Denki Kagaku Kogyo, MMM Carbon, Ketjen Black International Co. respectively, was added in carbon-Polytetrafluoroethylene (PTFE) electrode, which composition is activated carbon : carbon black : PTFE = 80 : 15 : 5 wt.%, and were compared with their electrochemical properties. The electrode with Ketjen Black has showed the lowest resistance than other carbon black, and also exhibited the better rate capability between 0.5 mA/cm$^2$ ∼ 100 mA/cm$^2$ current density in unit cell capacitor. On the other hand, as increasing the composition of Ketjen Black, the specific resistances of electrodes were decreased and Ketjen Black content higher than 15 wt% increased. The best rate capability was obtained at the electrode with 15 wt.% of Ketjen Black in unit cell capacitor. This behaviors would be correlated with the dense structure of electrode.

• Journal of the Korean Electrochemical Society
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• v.18 no.3
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• pp.95-101
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• 2015

In this article, we report the fabrication of Li-rich oxide nanoparticles for Li-ion batteries. Li-rich oxides are promising cathode materials because their capacity is much higher than commercial cathode materials. However, they have several disadvantages such as low rate capability due to their low ionic and electronic conductivity. This study focuses on the fabrication of nanoparticles to enhance the rate capability of Li-rich oxide. Two types of surfactants were introduced to disperse the particles and form the nano-sized particles. The Li-rich oxide nanoparticles showed improved rate capability than pristine sample.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.05b
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• pp.120-124
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• 2004

The protection performance and energy absorption capability are important for both MOAs for distribution lines and MOAs for high voltage systems, therefore the manufacturing technique of ZnO varistor elements with high ability against surge impacts is great important for high voltage systems. But until now ZnO varistors for low voltage class have been developed in Korea, ZnO varistors with the rate discharge current of 5, 10kA class for high voltage systems depend on an import from advanced countries, such as Japan or U.S.A, which have developed its in the late 1980s. So in the aspect of taking independent technique the development of ZnO varistors with the rate discharge current of 5, 10kA class for high voltage systems is important. In this research project ZnO varistor elements with diameters of 35mm and 70mm for the rate discharge current of 5, 10kA class for high voltage systems are manufactured, then various chemical composition and processing variables affected the electrical and the physical characteristics of these ZnO varistors are investigated.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.1
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• pp.64-70
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• 2006

In this study, the $LiCoO_2/LiNi_{1/3}Mn_{1/3}Co_{1/3}O_2$ mixed cathode electrodes were prepared and their electrochemical performances were measured in a high cut-off voltage. As the content of $LiNi_{1/3}Mn_{1/3}Co_{1/3}O_2$ increased in a mixed cathode, the reversible specific capacity and cycleability of the electrode enhanced, but the rate capability was deteriorated. On the contrary the rate capability of the cathode enhanced, but the reversible specific capacity and cycleability were deteriorated, increasing the content of $LiCoO_2$ in the mixed cathode. The cell of $LiCoO_2/LiNi_{1/3}Mn_{1/3}Co_{1/3}O_2$ ($50:50 wt\%$) mixed cathode delivered a discharge capacity of ca. 168 mAh/g at a 0.2 C rate. The capacity of the cell decreased with the current rate and a useful capacity of ca. 152 mAh/g was obtained at a 2.0 C rate. However, the cell showed very stable cycleability: the discharge capacity of the cell after 20th charge/discharge cycling maintains ca. 163 mAh/g.

• Journal of Satellite, Information and Communications
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• v.9 no.2
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• pp.110-113
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• 2014

In this paper, we address a problem of finding the optimum inner and outer code rates for a concatenated code in Gaussian binary symmetric channels. Clearly, as the inner code rate decreases, the error detection capability of the inner code increases. However, decreasing the inner code rate implies a decrease in error-correction capability of the outer code when overall code rate is fixed. With this notion in mind, we examine the optimum distribution of redundancy on the outer and inner codes to achieve a maximum performance gain in the concatenated coding scheme. Our analysis shows that the maximum coding gain can be obtained when the inner code rate is maximized and the outer code rate is minimized under the constraint of total code rate is fixed.

• Journal of the Korean Society of Tobacco Science
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• v.27 no.2
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• pp.163-170
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• 2005

A theoretical model for predicting the capability curve of cellulose acetate filter is derived. The pressure drop is expressed as a function of the filter dimensions, the tow fiber characteristics, the filter weight, the fluid flow rate, and a filter fiber factor. Where, the filter fiber factor is affected by the distribution of the tow fibers within the filter, the relative orientations of the tow fibers, and their cross-sectional shapes. The minimum and maximum fraction of solids in capability curves determined from experimental data. Also, the filter fiber factor is expressed as a function of the filter length, tow fiber length, and tow fiber diameter. Capability curves predicted by the suggested model in this work correspond well with capability curves by experimental data.