• Asian-Australasian Journal of Animal Sciences
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• 제18권9호
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• pp.1273-1278
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• 2005

This study is to evaluate the effect of different levels of ensiling density on the fermentation quality of guineagrass silages during the early stage of ensiling. Guineagrass at the milky ripe stage was chopped and ensiled into a small-scale laboratory silo at two ensiling density levels (high density at 95 g/silo and low density at 75 g/silo). Three silos per level were opened after six ensiling periods (0.5, 1, 1.5, 2, 3 and 7 days of ensiling) and the fermentation qualities were analyzed. Within the initial 1.5 days of ensiling there were not significant (p>0.05) differences in the fermentation qualities between two density levels silages, and an almost constant pH and no or only small amounts of lactic acid, acetic acid and total volatile fatty acids were detected. However, the high density silage significantly (p<0.05) increased the rate and extent of fermentation after 1.5 days of ensiling, which was well reflected in significantly (p<0.05) faster and larger pH decline and lactic acid production at each elapsed time as compared with the low density silage. This resulted in significantly (p<0.05) lower finial pH and significantly (p<0.05) higher lactic acid content at the end of the experiment. Moreover, there was higher AA content relative to LA in both the H-D and L-D silages during the full fermentation course, and resulted in the AA-type silage. There were generally somewhat or significantly (p<0.05) higher acetic acid, volatile fatty acids and ammonia-N/total nitrogen in the high density silage than in the low density silage during the initial 3 days of ensiling. However, there were higher (p>0.05) ammonia-N/total nitrogen and significantly (p<0.05) higher butyric acid content in the low density silage at day 7 of ensiling. The silages of two density levels showed an initial increase in glucose between 0.5 and 1 day for the high density silage and between 1 and 1.5 days for the low density silage, respectively, thereafter showed a large decrease until the end of the experiment. There were not large differences (p>0.05) in ethanol content between the low density and high density silages that showed small amounts within initial 3 days of ensiling. However, the low density silage had a significantly (p<0.05) higher ethanol content than the high density silage at the end of experiment. From the above results it was suggested that the increase in ensiling density was an effective method to improve the fermentation quality, especially for tropical grasses.

• 한국전기전자재료학회논문지
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• 제28권12호
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• pp.781-786
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• 2015

It is necessary for ferrite sheets to be fabricated with high packing density for excellent electrical properties and high strength. In this study, the relationship between the warpage and the packing density of ferrite green sheet, was investigated with amount variation of organic additives. With 0.4 wt% of dispersant, the packing density was about 48% and warpage appeared 0.5~1.3 mm high. With 1.4 wt% of dispersant, the packing density increased up to 57% and warpage appeared 0.8~2.1 mm high. With high packing density, warpage appeared along the edges of specimen, while with low packing density, deformation appeared over whole specimen inhomogeneously. It is thought that inhomogeneous deformation after sintering came from the inhomogeneity in green sheet prepared with badly dispersed slurry. With good homogeneity in green sheet from well-dispersed slurry, isotropic shrinkage is thought to have occurred along the distance from center to edges of specimen during sintering.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• 제5B권1호
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• pp.1-5
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• 2005

The vector magnetic property is defined as the relationship between the magnetic field strength vector H and the magnetic flux density vector B. It is very important for the development of high efficiency and the high-density electric machines. The electrical steel sheet for the machine core shows the remarkable vector behavior by the high magnetic flux density level. In this paper, the magnetic characteristic analysis using E&S2 model is introduced as the useful technology for the design and development.

• 한국정밀공학회지
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• 제26권12호
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• pp.41-46
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• 2009

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.740-741
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• 2006

The achievement of high density at reasonable cost is one of the major challenges of the P/M industry. One of the key factors contributing to the compressibility of a mix is the lubricant. New experimental lubricants enabling higher green density by conventional compaction or temperature-controlled die compaction were identified. The compaction and ejection characteristics of these new lubricants as measured with a fully instrumented lab press are presented and compared to that of conventional lubricants.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 D
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• pp.2505-2507
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• 2001

The RF signal is distorted since the cross-talk noise from adjacent tracks and ISI(Inter Symbol Interference) is also incresed as recording density is increased. These cross-talk noise and ISI are main reason of reading error for the embossed pits on the disc. In this study we suggest a new coding method, spaced modulation technique and a detection technique for the spaced modulation. We report the result shows detection performance is improved when we use the suggested spaced modulation code and the detection technique instead of conventional modulation code.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 D
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• pp.2008-2010
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• 2001

최근에 광 디스크 기기의 고배속화에 따라서 디스크의 재생 속도는 점차로 증가하고 있다. 이러한 경향에 따라 트랙킹 제어 루프에서 나타나는 디스크의 편심에 의한 외란의 영향은 더욱 커지게 되므로 기존의 선형 제어기만으로는 디스크의 편심량이 큰 경우에 고배속에서 원하는 트랙 추종 성능을 얻을 수가 없다. 본 논문에서는 이러한 문제점을 해결하기 위해서 반복 학습 제어 알고리즘과 드라이브 시스템의 액츄에이터의 주파수 응답 특성을 이용한 새로운 트랙 추종 제어 방법을 제안한다. 또한, 제안된 트랙 추종 제어 시스템의 제어 성능을 실험을 통하여 검증하여 본다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.228-231
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• 2002

We report the effect of density of thin films on moisture adsorption and hydration of MgO thin film, usually used as a protective layer in AC-PDP After hydration, lots of hemispherical shaped clusters, $Mg(OH)_2$, formed on the surface of MgO thin films. However clusters formed on low-density thin films were bigger than those on high-density films. From ERD spectra, it seemed that the concentration of hydrogen was very high in the region 20 nm from the surface of MgO thin film. The low-density thin film had more hydrogen than high-density thin film. From simulation results of ERD and RBS it was found that hydration reaction also occurred in the inner part of the film. So diffusion of Mg atoms from the inner part of the film to the surface and $H_2O$ molecules from the surface to the inner part of the film is important. And because low density thin film has many short paths for diffusion of Mg atoms and $H_2O$ molecules, low-density thin film is more hydrated. So to suppress hydration of MgO thin films, high-density thin film is needed.

• 디지털산업정보학회논문지
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• 제8권3호
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• pp.133-145
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• 2012

This paper describes the high density discrete wavelet transformation which is one that expands an N point signal to M transform coefficients with M > N. The double-density discrete wavelet transform is one of the high density discrete wavelet transformation. This transformation employs one scaling function and two distinct wavelets, which are designed to be offset from one another by one half. And it is nearly shift-invariant. Similarly, triple-density discrete wavelet transformation is a new set of dyadic wavelet transformation with two generators. The construction provides a higher sampling in both time and frequency. Specifically, the spectrum of the first wavelet is concentrated halfway between the spectrum of the second wavelet and the spectrum of its dilated version. In addition, the second wavelet is translated by half-integers rather than whole-integers in the frame construction. This arrangement leads to high density wavelet transformation. But this new transform is approximately shift-invariant and has intermediate scales. In two dimensions, this transform outperforms the standard and double-density discrete wavelet transformation in terms of multiple directions. Resultingly, the proposed wavelet transformation services good performance in image and video processing fields.

• Journal of Animal Science and Technology
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• 제48권1호
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• pp.49-58
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• 2006

본 연구는 비육돈 사료내 갯벌 미생물 유래 단백질 분해 효소제를 첨가하였을 때 성장률, 아미노산 소화율, 혈액성상, 육질 특성 및 분내 휘발성 지방산과 NH3-N 함량을 알아보기 위해 실시하였다. 3원 교잡종(Landrace×Yorkshire×Duroc) 비육돈 80두를 공시하였으며, 시험개시시의 체중은 60.08±2.69kg이었다. 시험설계는 기초사료내 영양소 함량과 효소제의 첨가 유뮤에 따라 high nutrient density diet 처리구, high nutrient density diet에 단백질 분해효소제를 첨가한 처리구(high nutrient density diet+0.1% protease), low nutrient density diet 처리구, low nutrient density diet 처리구에 단백질 분해효소제를 첨가한 처리구(low nutrient density diet+0.1% protease)로 4처리를 하여 처리당 5반복, 반복당 4마리씩 완전임의 배치하였다. 전체 사양시험 기간동안 일당증체량은 고 영양소 사료에 단백질 분해효소제를 첨가한 처리구가 저 영양소 사료를 급여한 처리구와 비교하여 유의적으로 증가하였다(P<0.05). DM과 N의 소화율은 고 영양소 사료를 급여한 처리구들 및 저 영양소 사료에 단백질 분해효소제를 첨가한 처리구가 저 영양소 사료를 급여한 처리구와 비교하여 유의적으로 증가하였다(P<0.05). 필수 아미노산 소화율은 저 영양소 사료에 단백질 분해효소제를 첨가한 처리구가 다른 처리구들에 비해 유의적으로 증가하였다(P<0.05). 비필수 아미노산 소화율에서는 고 영양소 사료에 단백질 분해효소제를 첨가한 처리구가 고 영양소 사료와 저 영양소 사료를 급여한 처리구들에 비해 유의적으로 증가하였다(P<0.05). BUN 함량은 고 영양소 사료에 단백질 분해효소제를 첨가한 처리구가 저 영양소 사료를 급여한 처리구와 비교하여 유의적으로 증가하였다(P<0.05). 육색에서는 명도를 나타내는 L*값은 저 영양소 사료를 급여한 처리구들이 고 영양소 사료를 급여한 처리구들과 비교하여 유의적으로 증가하였다(P<0.05). 결론적으로 비육돈 사료내 갯벌 미생물 유래 단백질 분해 효소제의 첨가는 성장률을 향상시켰고 아미노산 소화율 개선하였으며, BUN 함량과 육색에 영향을 미친 것으로 사료된다.(색인어：성장률, 아미노산 소화율, 혈액성상, 육질 특성, 휘발성 지방산, NH3-N)