• 신재생에너지
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• 제19권1호
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• pp.12-21
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• 2023

Governments and global companies are working towards using renewable sources of energy, such as solar, wind, and biomass, to reduce dependency on fossil fuels. In the defense sector, the new strategy seeks to increase the sustainable use of renewable energy sources to improve energy security and reduce military transportation. Renewable energy technologies are affected by factors such as climate, resources, and policy environments. Therefore, governments and global companies need to carefully select the optimal renewable energy sources and deployment strategies. Biomass is a promising energy source owing to its high energy density and ease of collection and harvesting. Many techniques have been developed to convert the biomass into electrical energy. Recently, diverse types of fuel cells have been suggested that can directly convert the chemical energy of biomass into electrical energy. The recently developed biomass flow fuel cell has significantly enhanced the power density several hundred times, reaching to ~100 mW/cm². In this review, we explore various strategies for producing electrical energy from biomass using modern methods, and discuss the challenges and potential prospects of this method.

• Clinical and Experimental Reproductive Medicine
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• 제11권2호
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• pp.69-76
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• 1984

In order to obtain high proportion of Y sperm the semen was laid over 6%,10% and 20% bovine serum albumin. Separated sperm were stained with quinacrine mustard in order to see F - body which could be seen in human Y sperm. But we could'nt find F-body in the bull sperm. So sperm were compared with size of sperm head. As a result of observation separated sperm was small in size of length and width of sperm head as compared with control sperm. So it was found that the proportion of Y sperm showed a marked increase in separated layer. Then the higher albumin density was, the higher the proportion of Y sperm which had smaller head and faster motility was. But the higher albumin density was, the lower the recovery rate of sperm was. So it was hard to separate Y sperm in oligospermia.

• Journal of Information Processing Systems
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• 제11권2호
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• pp.173-183
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• 2015

At present, it is simple to the electronic commerce credit scoring model, as a brush credit phenomenon in E-commerce has emerged. This phenomenon affects the judgment of consumers and hinders the rapid development of E-commerce. In this paper, that E-commerce credit evaluation model that uses a Gaussian density function is put forward by density test and the analysis for the anomalies of E-commerce credit rating, it can be fond out the abnormal point in credit scoring, these points were calculated by nonlinear credit scoring algorithm, thus it can effectively improve the current E-commerce credit score, and enhance the accuracy of E-commerce credit score.

• Fisheries and Aquatic Sciences
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• 제12권2호
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• pp.138-151
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• 2009

We quantitatively investigated compositions of fish and invertebrate bycatch in Korean shrimp fisheries. We sampled shrimp trawl bycatch from 48 commercial trawls over 1 year. These samples contained 108 taxa from 50 families, with 60 fish taxa contributing 51.2% of the total biomass and 48 invertebrate taxa 48.8%. However, 86.32% of the total individual organism density comprised invertebrates, while individual fishes made up the remainder. Within the bycatch, two fish species varied in population size structure by season, suggesting recruitment is seasonal in these taxa. Overall general catch characteristics (total bycatch biomass and organism density) varied significantly by season and tide, and a significant interaction effect was observed (season$\times$tide) on total density, but not on total biomass. The data collected will be used in designing a program of long-term bycatch monitoring.

• Smart Structures and Systems
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• 제3권3호
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• pp.357-372
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• 2007

Parametric density concept is proposed for a long-range pipeline health monitoring. This concept is designed to obtain the attenuation of ultrasonic guided waves propagating in underwater pipelines without complicated calculation of attenuation dispersion curves. For the study, three different pipe materials such as aluminum, cast iron, and steel are considered, ten different transporting fluids are assumed, and four different geometric pipe dimensions are adopted. It is shown that the attenuation values based on the parametric density concept reasonably match with the attenuation values obtained from dispersion curves; hence, its efficiency is proved. With this concept, field engineers or inspectors associated with long-range pipeline health monitoring would take the advantage of easier capturing wave attenuation value, which is a critical variable to decide sensor location or sensors interval.

• 한국의류산업학회지
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• 제9권4호
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• pp.425-430
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• 2007

This study was to present these results as basic data for the effects of Ayurvedic oil and the development of alopecia treatment programs. The results were as follows: 1) After Ayurvedic treatment, the hair density of vertex and occiput were 264.2 hair/$cm^2$ and 299.8 hair/$cm^2$ each. There was the increase of total 29.2% in hair density. 2) The hair growth rates on vertex and occiput after Ayurvedic treatment were 310.8 ${\mu}m$/day and 345.8 ${\mu}m$/day respectively, there was the increase of total 79% in hair growth.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.655-659
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• 2001

Resident time of the continuous and Instantaneous centrifugal separator using that separates the light and heavy liquids by use of density difference is the orptical factor that affects significantly the chemical metial extraction and the productivity in the chemical and mechanical process. In this paper, the overflow of the device is investigated under consideration of the relationships between inclination angle of liquid feeding screw and the centrifugal force. From the design of the length of a centrifugal separator, the radiuses of rotor and housing, theoretical formulation on the contact radius of separation weir is established through the experiments. From the experiments, it is identified that how much the capacity of inlet impeller and the emulsion phenomenon depend on the screw angle of inlet impeller. Also, we investigate the separation condition and the resident times that are functions of the phase ratio and density.

• 농촌지도와개발
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• 제7권1호
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• pp.175-180
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• 2000

느타리, 표고, 팽이, 차가버섯균의 배양일수별 균사생장과 균사밀도를 조사한 결과, 세라믹스 제조 온도별로는 $1000^{\circ}C$ 보다는 $800^{\circ}C$에서 전반적인 균사생장과 밀도가 좋았다. 세라믹스 함량에 따른 균사생장은 0.16%까지 높을수록 빨랐으나 균사밀도를 고려할 때 0.12% 첨가가 가장 양호하였다.

• 한국표면공학회지
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• 제38권5호
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• pp.179-182
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• 2005

Indium Tin Oxide (ITO) thin films were deposited from various target densities ($98.7\%\~99.6\%$) using RF magnetron sputtering. Effect of the sputtering target densities on the structural, electrical and optical properties of deposited ITO thin films was investigated. The preferable (400) crystalline orientation peak was observed on the films deposited from > $99.0\%$ target density. Higher target density produced films with higher roughness but lower resistivity. All of the deposited films showed optical transmittance more than $85\%$ in the visible wavelength region. It is necessary to use the highest target density for sputtering deposition of ITO thin films.

• 한국세라믹학회지
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• 제31권3호
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• pp.312-320
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• 1994

Effect of the laser shot number on the particulates density of the pulsed laser deposited YBa2Cu3O7-x thin films and the laser irradiated surface morphology of the YBa2Cu3O7-x bulk target have been investigated. Until 100 laser shots of cumulative irradiation, the films has the particulates density of ~103 mm-2. However, after 100 laser shots, the density was increased more than 10 times. This results has been explained by the change of particulate ejection path with the development of conical structure at the target surface.