• 한국축산식품학회지
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• 제24권3호
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• pp.209-215
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• 2004

본 시험은 고에너지 수준의 사료를 급여한 돼지의 사양성적, 돈육의 도체 특성, 일반성분, 이화학적 특성 및 지방산 조성에 미치는 영향을 조사하기 위해 실시하였다. 80$\pm$3 kg의 삼원교잡종 120두를 공시하여 비육돈 사료 변화의 영양소 수준에 따라 저에너지 DE 3,290 kcal/kg, CP 14.5%, Lysine 0.70%, Ca 0.78로 배합한 사료를 38일간 급여하였고, 고에너지 DE 3,350 kcal/kg, CP 15.0%, Lysine 0.10%, Ca 0.78%로 배합한 사료를 27일간 급여하였다. 저에너지와 고에너지 사료를 급여한 돼지의 종료체중이 101 kg내외에 도달했을 때 도축하여 시험에 공시하였다. 고에너지 사료를 급여한 돼지가 일당 증체량이 높았고, 사료섭취량과 사료요구율은 낮았다(p<0.05). 도체특성과 일반성분은 차이를 보이지 않았다 이화학적 특성 중 고에너지 사료를 급여한 돈육의 가열 감량과 황색도는 저에너지 사료를 급여한 돈육에 비해 현저히 높게 나타내었다(p<0.05). 지방산 조성에서는 저에너지와 고예너지 사료를 급여한 돈육에서 차이를 보이지 않았다. 이상에서 고에너지 사료를 27일간 급여한 돼지는 저에너지 사료를 38일간 급여한 돼지에 비해 성장률이 향상되었고, 돼지의 도체 특성, 물리적 특성 및 지방산 조성에는 미치지 않았지만 돈육의 가열 감량과 황색도가 높았다.

• Composites Research
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• 제36권3호
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• pp.180-185
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• 2023

본 논문에서는 스프레딩된 SiC 섬유를 적용해 SiC_f/SiC를 제조하였을 경우, 섬유의 분산도가 복합소재의 내부구조 및 기계적 강도에 어떠한 영향을 주는지를 연구하였다. Spread SiC 섬유를 적용한 시편의 섬유 체적비는 non-spread 시편 대비 9%p 감소하였으며, 수지 슬러리가 섬유 사이로 더 원활히 함침되어 기지내 기공도 거의 발견되지 않았다. 각 시편의 섬유 분산도를 비교하기 위해, 복합소재 내 섬유간 이격거리를 수치화하고 평가하는 방법을 제안하였다. 그 결과 spread 시편의 섬유간 중심거리는 non-spread 시편 대비 2.23 ㎛ 증가하였으며, 섬유 표면 사이 거리는 42.6%로 대폭 증가하였다. 3점 굽힘시험을 통해 spread 시편의 굽힘강도가 non-spread 시편 대비 49.3% 가량 높으며, 시험 데이터의 편차도 더 균일함을 확인하였다. 따라서 복합소재 기지내 SiC 섬유의 분산도 향상이 SiC_f/SiC의 균일한 기지상 치밀화와 기계적 강도 증가에 매우 큰 영향을 미친다는 점을 알 수 있다.

• Current Optics and Photonics
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• 제1권3호
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• pp.203-206
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• 2017

We report a passive Q-switching of an all-fiber erbium-doped fiber laser delivering high pulse energy by using a high quality single-walled carbon nanotube saturable absorber (SWCNT-SA). A side-polished fiber coated with the SWCNT is employed as an in-line SA for evanescent wave interaction between the incident light and the SWCNT. This lateral interaction scheme enables a stable Q-switched fiber laser that generates high pulse energy. The central wavelength of the Q-switched pulse laser was measured as 1560 nm. A repetition rate frequency of the Q-switched laser is controlled from 78 kHz to 190 kHz by adjusting the applied pump power from 124 mW to 790 mW. The variation of pulse energy from 51 nJ to 270 nJ is also observed as increasing the pump power. The pulse energy of 270 nJ achieved at maximum pump power is 3 times larger than those reported in Q-switched all-fiber lasers using a SWCNT-SA. The tunable behaviors in pulse duration, pulse repetition rate, and pulse energy as a function of pump power are reported, and are well matched with theoretical expectation.

• 한국수소및신에너지학회논문집
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• 제27권6호
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• pp.753-763
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• 2016

High temperature sodium/sulfur battery(Na/S battery) has good electrochemical properties, but, the battery has some problems such as explosion and corrosion at al. because of using the liquid electrodes at high temperature and production of high corrosion. Room temperature sodium/sulfur batteries (NAS batteries) is developed to resolve of the battery problem. To recently, room temperature sodium/sulfur batteries has higher discharge capacity than its of lithium ion battery, however, cycle life of the battery is shorter. Because, the sulfur electrode and electrolyte have some problem such as polysulfide resolution in electrolyte and reaction of anode material and polysulfide. Cycle life of the battery is improved by decrease of polysulfide resolution in electrolyte and block of reaction between anode material and polysulfide. If room temperature sodium/sulfur batteries (NAS batteries) with low cost and high capacity improves cycle life, the batteries will be commercialized batteries for electric storage, electric vehicle, and mobile electric items.

• 한국수소및신에너지학회논문집
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• 제30권1호
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• pp.43-48
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• 2019

This study investigates the electrochemical characteristics of the hybrid cell that combined the advantageous characteristics of Li secondary battery and supercapacitor, high energy density and high power density, respectively. Electrochemical behaviors of the hybrid cell was characterized by charge/discharge, cycle and impedance tests. The hybrid cell using Li secondary battery and supercapacitor had better discharge capacity and cycle performance than that of using Li secondary battery only. Proper design of such a hybrid cell system is expected to result in substantial benefits to the well being of the Li secondary battery. The hybrid cell involving Li secondary battery for high energy density and supercapacitor for high power density may be the possible solution for future energy storage system.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.305-307
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• 2014

Pyroprocessing (or pyrometallurgy) is the way of extracting from materials subjected to high temperatures. Generally, this process has a high energy consumption because of mass production and heating-up. To attain effective and efficient energy management, energetic analysis using 0-dimensional model is usually conducted. However, this model can lead to a misunderstanding about energy evaluation due to many assumptions and limitations. In this study, heat & mass balance using 0-dimensional model was reviewed to systematize problems and considerations in general process energy evaluation.

• Bulletin of the Korean Chemical Society
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• 제33권11호
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• pp.3871-3874
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• 2012

• Journal of Radiation Protection and Research
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• 제43권3호
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• pp.97-106
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• 2018

Background: A cargo container scanner using a high-energy X-ray generates a fan beam X-ray to acquire a transmitted image. Because the generated X-rays by LINAC may affect the image quality and radiation protection of the system, it is necessary to acquire accurate information about the generated X-ray beam distribution. In this paper, a diode-based multi-channel spatial dose measuring device for measuring the X-ray dose distribution developed for measuring the high energy X-ray beam distribution of the container scanner is described. Materials and Methods: The developed high-energy X-ray spatial dose distribution measuring device can measure the spatial distribution of X-rays using 128 diode-based X-ray sensors. And precise measurement of the beam distribution is possible through automatic positioning in the vertical and horizontal directions. The response characteristics of the measurement system were evaluated by comparing the signal gain difference of each pixel, response linearity according to X-ray incident dose change, evaluation of resolution, and measurement of two-dimensional spatial beam distribution. Results and Discussion: As a result, it was found that the difference between the maximum value and the minimum value of the response signal according to the incident position showed a difference of about 10%, and the response signal was linearly increased. And it has been confirmed that high-resolution and two-dimensional measurements are possible. Conclusion: The developed X-ray spatial dose measuring device was evaluated as suitable for dose measurement of high energy X-ray through confirmation of linearity of response signal, spatial uniformity, high resolution measuring ability and ability to measure spatial dose. We will perform precise measurement of the X-ray beamline in the container scanning system using the X-ray spatial dose distribution measuring device developed through this research.

• Journal of the Optical Society of Korea
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• 제12권3호
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• pp.178-185
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• 2008

Recent progress in high power lasers enables us to access a regime of high-energy-density and/or ultra-strong fields that was not accessible before, opening up a fundamentally new physical domain which includes laboratory astrophysics and laser nuclear physics. In this article, new applications of high-energy and ultra-intense laser will be reviewed.

• 대한조선학회논문집
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• 제53권4호
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• pp.307-314
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• 2016

Energy flow analysis(EFA) is a representative method that can predict the statistical energetics of structures at high frequencies. Generally, as the frequency increases, the shear distortion and rotatory inertia effects in the out-of-plane motion of beams or plates become important. Therefore, to predict the out-of-plane energetics of coupled structures in the high frequency range, the energy flow analyses of Timoshenko beam and Mindlin plate are required. Unlike the energy flow model of Kirchhoff plate, the energy flow model of Mindlin plate is composed of three kinds of energy governing equations(out-of-plane shear wave, bending dominant flexural wave, and shear dominant flexural wave). This paper performed the energy flow finite element analysis(EFFEA) of coplanar coupled Mindlin plates. For EFFEA of coplanar coupled Mindlin plates, the energy flow finite element formulation of out-of-plane energetics in the Mindlin plate was performed. The general EFFEA program was implemented by MATLAB® language. For the verification of EFFEA of Mindlin plate, the various numerical applications were done successfully.