• Journal of Advanced Marine Engineering and Technology
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• v.25 no.1
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• pp.146-154
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• 2001

In almost all real situations, there will be a radiant interchange between adjacent fins with the base surface as well as with the external environment. In the problem of this study, a rectangular fin is attached to a based. Our concern is whether the convective fin efficiency can be increased by the radiation heat exchanged between the fin and the base surface and how much. If the fin temperature toward the tip increased by the effect of radiation, the convective heat transfer increase due to the temperature difference between the ambient temperature and the surface temperature of the fin. If this true, the efficiency of the fin due to the radiation will increase. Attention is directed toward several parameters which have major roles on getting values of the fin efficiencies in several different values of parameters. Many different cases are, therefore, to be examined to have maximum fin efficiency by varying the values of each parameter.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.E1
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• pp.13-20
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• 2002

The electrical and chemical properties of the dielectric barrier discharge (DBD) process for the benzene removal were investigated. The benzene removal was initiated with the applied voltage higher than the discharge onset value. The removal efficiency over 95 % was obtained at approximately 1.6 kJ lite $r^{r-1}$ of the electrical energy density. The increase of the inlet concentration decreased the removal efficiency. However, the benzene decomposition rate increased with the inlet concentration . While the increase of the gas retention time enhanced the removal efficiency, the decomposition rate decreased. Identification of the optimum condition between the decomposition rate and the removal efficiency is required for field applications of the DBD process.s.

• International journal of advanced smart convergence
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• v.9 no.2
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• pp.179-184
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• 2020

Recently, webtoons-based animations have been expanding in Korea, where the role of mobile devices is growing, and media videos such as "YouTube" and "Tik-Tok," which have shorter screening and production cycles than traditional feature films, dramas, and animations, are attracting attention and being enjoyed by public. In order to produce animation content that fits the trend of this shortening video and production cycle, efficiency must be increased not only in story but also in production. Production methods and production technologies need changes to increase efficiency. Animation using motion capture, which is highly production-efficient, is widely used in movies that shows realistic movements, but still has little use in producing cartoon-style animations with exaggerated movements. We analyzed the production method of 2D animation and CG animation and applied the result to CG animation to increase the efficiency of production and production. The methods of production through such experiments are expected to help improve the efficiency of producing animation content that is suitable for the latest trends such as webtoon animation.

• Journal of the Korean Society of Combustion
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• v.22 no.4
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• pp.51-56
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• 2017

The decomposition of tetrafluoromethane has been investigated with the reaction mechanism proposed for freely propagating $CH_4/CF_4/O_2/N_2$ premixed flames on the oxygen enrichment. The factors affecting on the removal efficiency of tetrafluoromethane were analyzed. The increase in flame temperature due to oxygen enrichment has a great influence on the removal efficiency of tetrafluoromethane. At the same oxygen enrichment condition, the removal efficiency in the rich flame is higher than one in the lean flame. The increase of the F/H ratio leads to decrease the flame temperature and the removal efficiency of tetrafluoromethan is decreased at the flame temperature of 2600 K or lower, The elementary reactions that dominate the consumption of tetrafluoromethane are (R1) $CF_4+M=CF_3+F+M$ and (R2) $CF_4+H=CF_3+HF$. (R1) has the greatest effect on the consumption of tetrafluoromethane under the oxygen enhanced flames.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.2
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• pp.114-121
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• 2013

High efficiency operation is required for motors of vehicle to increase fuel efficiency due to the regulation of exhaust gas. This paper presents a control method of fuel pressure to increase fuel efficiency and a sensorless control method of BLDC motor to get higher efficiency than conventional brushed DC motor. Initial rotor position of BLDC motor is detected from current value that is occurred by test voltage pulse and rotor is accelerated by defined sequence to enter sensorless operation mode. The algorithm to control flow rate of fuel pump uses PI controller that is control motor speed to maintain the target fuel pressure commanded by ECU.

• Journal of Korean Society of Water and Wastewater
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• v.12 no.4
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• pp.106-111
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• 1998

In this paper,to know sedimentation efficiency compared with sedimentation efficiency's experiment result by general and inclination plate settler, its and fin stick of inclination plate. Experiment result is inclination plate settler increase sedimentation efficiency's 6.96% than general settler, When fin stick of inclination plate is the optimum condition of one side, inclination plate's angle $60^{\circ}$, fin's width 67mm, fin's interval 200mm, sedimentation efficiency of many experimental condition increase 6.63% than inclination plate settler. A studdy on the site plottage through the result, Water inclination plate settler of the present's application reduce 30% of its than general settler. According to the above statements, fin stick of inclination plate's sedimentation efficiency is 0.95 times of inclination plate settler's. Concluding remarks, Fin stick of inclination plate reduce 28.5% of its than inclination plate settler.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.36 no.1
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• pp.17-23
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• 2013

This study analyzed the efficiencies of Korean fisheries cooperative's 97 operation offices in the capital and surrounding area. We used the DEA model for checking the technical and scale efficiencies in the financial business of them. We divided the business into two parts, the productivity (efficiency for increasing deposit and loan) and profitability (efficiency for increasing the profit and reducing the risk from the loan). The results show that the additional profitability increase is very difficult because most of the offices have full technical efficiency for profitability. But additional analysis based on Slack-based Measure (SBM) DEA model shows that Kyung-Gi region can increase the profitability. SBM model analysis also gives us the possibility that customized policy can apply to each offices considering each factors affecting the productivity and profitability.

• The Journal of Economics, Marketing and Management
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• v.11 no.3
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• pp.25-35
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• 2023

Purpose: This paper examines whether foreign aid influences public sector efficiency in policy areas of administration, education, and stability. Research design, data and methodology: The study uses panel data of 77 aid recipient developing countries over the period 2000-2020 and employs various panel data techniques to estimate. Results: We found that a percentage change in foreign aid increases administrative efficiency by 0.02 to 0.04 on average ceteris paribus in the short run. On the other hand, a percentage increase in foreign aid decreases education efficiency by 0.005 to 0.006 on average. While the impact of foreign aid on the policy area of stability is insignificant. Conclusions: The empirical results of this study have important implications for both donors and aid recipient countries. It suggests that to get positive influence from foreign aid, in the area of education and stability, the recipient countries need to increase accessibility of secondary schools with quality education especially; technical and vocational. Also, the donor should provide a minimum threshold amount of foreign aid to developing countries for reforming the institutions' capacity building.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.1
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• pp.18-23
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• 2004

Effect of initial protein concentration on the protein removal rate was assessed for seawater aquarium using a foam separator. Protein removal rate was increased and removal efficiency was decreased with the increase of initial protein concentration. Enrichment ratio was decreased and foam generation rate was increased with the increase of initial protein concentration. Total suspended solids (TSS) removal rate was increased with the increase of initial protein concentration, and TSS removal efficiency was decreased with the increase of initial protein concentration. Turbidity removal rate and removal efficiency were increased with the increase of initial protein concentration.

• Journal of Power System Engineering
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• v.10 no.3
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• pp.11-16
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• 2006

The pressure fluctuation in the intake and exhaust pipe of 4 stroke-cycle diesel engine is caused by reciprocating motion of piston for suction of fresh air and exhaust of burned gas. this gas dynamic effect can be utilized for increase the volumetric efficiency. Many empirical studies have been carried out to investigate the effects of intake pulsating flow on the volumetric efficiency. However, when the gas dynamic effects are utilized for the variable speed engine to increase its performance, The speed range in which the maximum volumetric efficiency is limited and there occurs some difficulties in lay-out of intake system because it become too long. During induction process, as waves travel both directions, they are reflected and interacted each other and pressure waves are transmitted through it. Hence, the flow becomes more complex and unsteady flow. These pressure waves act upon intake pulsating flow and affects on the volumetric efficiency. In this paper the effects of pulsating flow of intake and exhaust pipes on volumetric efficiency were examined and evaluated. It was found that volumetric efficiency was affected by pulsating flow of intake and exhaust pipes.