• 제목/요약/키워드: Feed size

검색결과 760건 처리시간 0.028초

향상된 절삭력 예측을 위한 Size Effect 모델의 개발 (Development of the Size Effect Model for More Accurate Cutting Force Prediction)

  • 윤원수;조동우
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2000년도 춘계학술대회 논문집
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    • pp.995-1000
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    • 2000
  • In this paper. a mechanistic model is first constructed to predict three-dimensional cutting forces, and the uncut chip th thickness is calculated by following the movements of the position of the center of a cutter, which varies with the nominal feed, cutter deflection and runout. For general implementation to a real machining, this paper presents the method that determines constant cutting force coefficients, irrespective of the cutting conditions or cutter rotation angles. In addition, this study presents the approach which estimates runout-related parameters. the runout offset and its location angle, using only one measurement of cutting forces. For more accurate cutting force predictions, the size effect has to be considered in the cutting force model. In this paper, two approximate methods are suggested since the strict approach is practically impossible due to a measurement problem. The size effect is individually considered for narrow and wide cuts.

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The Limiting Sequence and Proper Ratio of Lysine, Methionine and Threonine for Calves Fed Milk Replacers Containing Soy Protein

  • Wang, Jianhong;Diao, Qiyu;Tu, Yan;Zhang, Naifeng;Xu, Xiancha
    • Asian-Australasian Journal of Animal Sciences
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    • 제25권2호
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    • pp.224-233
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    • 2012
  • The limiting sequence and relative ratio of lysine (Lys), methionine (Met), and threonine (Thr) for calves about 2 mo of age fed milk replacers (MR) containing soy protein are not clearly defined. The objective of the study was to investigate the effect of supplementing MR containing 22% CP, half from soy protein concentrate (SPC, 40.56% CP, flour) and half from whey proteins, with Lys, Met, and Thr to estimate amino acid (AA) sequence and their relative ratio for calves about 2 mo of age. A method of partial deduction of AA was adopted. Twenty-four newborn calves (half males and half females, $40.7{\pm}0.9$ kg of BW) were fed 1 of 4 MR diets for 56 d (n = 6/diet). The diets were supplemented with all (positive control) or with 2 of the 3 AAs: Lys, Met and Thr, (i.e., PC (22% CP, 2.34% Lys, 0.72% Met and 1.80% Thr), PC-Lys (22% CP, 1.64% Lys, 0.72% Met and 1.80% Thr), PC-Met (22% CP, 2.34% Lys, 0.50% Met and 1.80% Thr), and PC-Thr (22% CP, 2.34% Lys, 0.72% Met and 1.26% Thr)). Calves were fed thrice daily; starter (20% CP, 1.03% Lys, 0.30% Met and 0.69% Thr), hay (3.23% CP, 0.29% Lys, 0.12% Met and 0.23% Thr) and water were offered free choice. Starter and hay were only offered beginning on d 36 (after 5 wk) and d 43 (after 6 wk), respectively. BW, body size and blood samples measures were taken every two weeks. Three-day total collection of feed refusals, feces, and urine were recorded starting at d 33 and d 54 of age, respectively. From the results, the limiting sequence and relative ratio between the 3 AAs in calves with different diet structures were calculated. The limiting sequence of the 3 AAs were ranked as Lys, Met and Thr; the proper ratio was 100:29:70 for MR-only diet and 100:30:60 for diets consisted of MR, starter and hay. Nitrogen digestion and utilization and nutrient digestibility were negatively affected by AA deletion treatments. From the evidence of this experiment, it did not appear that the AA limiting sequence was selectively altered by differences in diet structures such as would be encountered in practice. The relative ratio between the 3 AAs varied with the offer of starter and hay to calves, and the average ratio was 100:29.5:65 for calves during 2 to 10 wk of age.

Grains and Roughage Production and Its Utilization in Asian-Australasian Region - Review -

  • Bhat, P.N.;Bansil, P.C.
    • Asian-Australasian Journal of Animal Sciences
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    • 제12권3호
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    • pp.481-492
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    • 1999
  • Asian-Australasian region comprises of 82 countries spread over varying agro economic zones, habitats and ecosystems varying from dry hot to humid tropics and cold deserts. The literacy standards vary from very low to almost 100 percent. On the basis of economic development there are 4 countries Japan, Australia, New Zealand and Korea which are developed countries, rest are in varying states of development and growing economically very rapidly. Based on Agro ecosystems and farming practices, we have chosen four countries for indepth study in this paper namely China, Thailand, Indonesia and India. They represent 70% of the bovine and poultry population of the region. This paper makes a comparative study of the grain and roughage production and utilization at present and in 2000 A.D. by examining information on feed rates demand patterns and feed requirements in these four countries keeping in view the size and growth of bovine and poultry population and dietary pattern of the people. It has been observed, there has so far been no country level detailed study on the livestock feed requirements. Apart from conceptual discrepancies, most of the estimates given in various reports brought out by the national governments and international agencies do not have any scientific basis. Hence an inter-country comparison is virtually impossible on the basis of the available information. We have however, attempted to analyse the dietary pattern in the different countries, feedgrains requirements, availability of feed based on the information available from the various published and unpublished reports. We have given an inter-country comparison of feed rate and feed requirements which, however, needs to be tested by carrying out a micro level study in each selected country.

Ileal Amino Acid Digestibility in Different Cultivars of Chinese Rapeseed Meals for Growing-finishing Pigs

  • Pengbin, Xi;Li, Defa;Gong, Liming
    • Asian-Australasian Journal of Animal Sciences
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    • 제15권9호
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    • pp.1326-1333
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    • 2002
  • Studies were conducted with nine barrows, average initial body weight $44.5{\pm}2.1kg$, fitted with a T-cannula at the distal ileum, to determine the apparent ileal (and true) digestibility (AID and TID) of CP and AA in different cultivars of rapeseed meals and soybean meal. The barrows were fed either a casein diet or one of eight corn starch-based semipurified diets, formulated to contain 17.0% CP (DM basis) with one of seven different cultivars of rapeseed meal or soybean meal as the sole source of dietary protein, according to a six-period, nine-treatment, incomplete Latin Square. Chromic oxide (0.5%) was used as a digestibility marker. The pigs were fed of 4% of body weight twice daily, at 08:00 and 20:00 h. Ileal digesta were collected at 2 h intervals daily from 5 d to 7 d. The AID or TID values of CP and most AA (Cysteine excluded) were significantly lower in the rapeseed meals than in soybean meal (p<0.05). There were significant differences in the AID or TID values of CP and AA among the seven different cultivars rapeseed meals (p<0.05); the seven rapeseed meals were arranged according to the size of the AA digestibility values of the rapeseed meals from the greatest to the least, as Zayou 59, Youyan 7, Ganyou 16, Qingyou 2, Huaza 3, Ningza 1 and Lianglou 586; differences in CP, AA, NDF and ADF contents in the rapeseed meals were mainly responsible for the variation in the AID or TID values of AA among rapeseed meals. The AID value of CP can be used as an index of the AID or TID values of most AA in rapeseed meals. However, the AID value of CP was less appropriate as a direct indicator of the AID or TID values for cysteine, methionine, tryptophan, phenylalanine and proline.

밀리미터파(W대역) 이중편파 모노펄스 급전 구조 설계 및 제작 방안 연구 (A Study on Design and Manufacturing Methods of Dual-Polarization Monopulse Feed Structure in Millimeter-wave(W band))

  • 백종균;이형기;김영완;채희덕;주지한;김재식
    • 한국인터넷방송통신학회논문지
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    • 제23권6호
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    • pp.47-53
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    • 2023
  • 본 논문은 밀리미터파(W대역)의 이중편파 신호를 모노펄스 신호로 변환하는 도파관 타입의 급전 구조를 설계하고 제작 방안을 제시하였다. W대역과 같은 높은 주파수 대역에서는 도파관의 크기가 매우 작기 때문에 복잡한 구조의 제작이 매우 어렵다. 따라서 높은 주파수 대역의 도파관 타입 급전 구조는 제작성이 중요하기 때문에 전주도금(Electro Forming) 방식과 확산접합 방식을 본 연구에서 제안하고 검증하였다. 설계된 모노펄스 급전 구조는 90도 하이브리드에 90도 위상 천이기를 결합한 180도 하이브리드 8개와 이중편파 분리를 위한 직교모드변환기(OMT) 4개로 구성된다. 설계된 급전구조는 전주도금(Electro Forming)과 확산접합 제작 방식에 용이하도록 설계하였으며, 제작된 모노펄스 급전구조는 네트워크 분석기를 통해 검증하였다. 제안한 두 가지 제작 방안은 측정된 포트의 신호 크기와 위상을 통해 모노펄스 신호가 잘 생성되는 것을 확인하였다.

A Novel Approach for Controlling Process Uniformity with a Large Area VHF Source for Solar Applications

  • Tanaka, T.
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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    • pp.146-147
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    • 2011
  • Processing a large area substrate for liquid crystal display (LCD) or solar panel applications in a capacitively coupled plasma (CCP) reactor is becoming increasingly challenging because of the size of the substrate size is no longer negligible compared to the wavelength of the applied radio frequency (RF) power. The situation is even worse when the driving frequency is increased to the Very High Frequency (VHF) range. When the substrate size is still smaller than 1/8 of the wavelength, one can obtain reasonably uniform process results by utilizing with methods such as tailoring the precursor gas distribution by adjustingthrough shower head hole distribution or hole size modification, locally adjusting the distance between the substrate and the electrode, and shaping shower head holes to modulate the hollow cathode effect modifying theand plasma density distribution by shaping shower head holes to adjust the follow cathode effect. At higher frequencies, such as 40 MHz for Gen 8.5 (2.2 m${\times}$2.6 m substrate), these methods are not effective, because the substrate is large enough that first node of the standing wave appears within the substrate. In such a case, the plasma discharge cannot be sustained at the node and results in an extremely non-uniform process. At Applied Materials, we have studied several methods of modifying the standing wave pattern to adjusting improve process non-uniformity for a Gen 8.5 size CCP reactor operating in the VHF range. First, we used magnetic materials (ferrite) to modify wave propagation. We placed ferrite blocks along two opposing edges of the powered electrode. This changes the boundary condition for electro-magnetic waves, and as a result, the standing wave pattern is significantly stretched towards the ferrite lined edges. In conjunction with a phase modulation technique, we have seen improvement in process uniformity. Another method involves feeding 40 MHz from four feed points near the four corners of the electrode. The phase between each feed points are dynamically adjusted to modify the resulting interference pattern, which in turn modulate the plasma distribution in time and affect the process uniformity. We achieved process uniformity of <20% with this method. A third method involves using two frequencies. In this case 40 MHz is used in a supplementary manner to improve the performance of 13 MHz process. Even at 13 MHz, the RF electric field falls off around the corners and edges on a Gen 8.5 substrate. Although, the conventional methods mentioned above improve the uniformity, they have limitations, and they cannot compensate especially as the applied power is increased, which causes the wavelength becomes shorter. 40 MHz is used to overcome such limitations. 13 MHz is applied at the center, and 40 MHz at the four corners. By modulating the interference between the signals from the four feed points, we found that 40 MHz power is preferentially channeled towards the edges and corners. We will discuss an innovative method of controlling 40 MHz to achieve this effect.

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Effects of Particle Size of Barley on Intestinal Morphology, Growth Performance and Nutrient Digestibility in Pigs

  • Morel, P.C.H.;Cottam, Y.H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제20권11호
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    • pp.1738-1745
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    • 2007
  • A growth trial and a digestibility trial were conducted to examine the effect of feed particle size on the performance, nutrient digestibility, gastric ulceration and intestinal morphology in pigs fed barley-based diets. Barley was processed through a hammer mill to achieve four diets varying in particle size (average particle $size{\pm}standard $deviation): coarse ($1,100{\pm}2.19\;{\mu}m$), medium ($785{\pm}2.23\;{\mu}m$), fine ($434{\pm}1.70\;{\mu}m$) and mixed (1/3 of coarse, medium and fine) ($789{\pm}2.45\;{\mu}m$). Sixty-four entire male pigs were used in the growth trial and the diets were fed ad libitum between 31 kg and 87 kg live weight. Following slaughter, stomach and ileal tissues were scored for integrity (ulceration or damage) and histological measurements taken. Twenty-four entire male pigs were used in the digestibility trial, which involved total faecal collection. Over the entire growth phase, there were no differences (p>0.05) in average daily gain and feed conversion ratio between pigs fed diets of different particle size. Pigs fed the coarse and medium diets had lower (p<0.05) stomach ulceration scores (0.20 and 0.25, respectively, on a scale from 0 to 3) than those fed the mixed (0.69) or the fine diets (1.87). The stomachs of all animals fed the fine diet had lesions and stomach ulcerations were present only in this group. Pigs fed the fine diet had thicker (p<0.001) ileal epithelial cell layer with no differences (p>0.05) being observed for villous height or crypt depth. Faecal digestibility coefficients of neutral and acid detergent fibre were the highest (p<0.05) for the mixed diet, intermediate for the fine and coarse diets and the lowest for the medium diet. A similar numerical trend (p = 0.103) was observed for the apparent faecal energy digestibility coefficient. It is concluded that, with barley based diets, a variation in average particle size between $400{\mu}m$ and $1,100{\mu}m$ had no effect on pig performance but the fine dietary particle size affected the integrity of the stomach, as well as the structure of the small intestine, thus compromising overall gut health. Our data also demonstrate that changes in particle size distribution during the digestion process, rather than average particle size or particle size variation, are related to apparent faecal digestibility.

초고출력 안테나 시스템 급전용 다중 모드 혼 안테나 설계에 관한 연구 (A Study on Design of Multimode Feed Horn Antenna for High Power Microwave Antenna System)

  • 이상흔;윤영중;이병무;소준호
    • 한국전자파학회논문지
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    • 제17권5호
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    • pp.476-482
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    • 2006
  • 본 논문에서는 초고출력 안테나 시스템의 급전용 다중 모드 혼 안테나를 제안한다. 제안된 초고출력용 급전 혼 안테나는 모드 변환기와 연결되며, 전원부와 반사판 안테나의 사이에 위치한다. 초고출력 시스템의 경우 급전 안테나의 spillover를 고려한 -25 dB 빔 폭이 반사판 안테나의 크기를 결정하므로 반사판 안테나의 소형화를 위해 -25 dB 빔 폭을 줄인 급전용 다중 모드 혼 안테나를 설계 및 제작하였다. 그 결과 제안된 다중 모드 혼 안테나를 이용한 급전 시스템의 이득은 27 dBi이며 반사 손실은 10 GHz에서 -22 dB 이하의 값이 측정되었다. 또한 -25 dB 범 폭은 수직 평면과 수평 평면에서 각각 $20.24^{\circ}$$28.92^{\circ}$로 측정되었고 이는 기존의 혼 안테나를 이용한 급전 시스템의 빔 폭보다 약 $10^{\circ}$가량 작은 값으로, 제안된 혼 안테나는 초고출력 안테나 시스템 소형화에 적합한 형태임을 확인하였다.

環境條件이 仔豚의 成長과 行動에 미치는 影響 (Effects of Environmental Factors on Growth Performances and Behavioural Patterns of Weanling Pigs)

  • 김두환;김철욱;송영민;진상근
    • 한국축산시설환경학회지
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    • 제1권2호
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    • pp.137-144
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    • 1995
  • 두당 돈방면적과 돈군의 크기 등 돼지의 사육환경 조건이 자돈의 성장과 행동에 미치는 영향을 구명하기 위하여 이유후부터 체중 30kg까지의 자돈을 총 18돈방에 300두를 공시하여 시험하였다. 사료급여는 습식급여로 하였으며 두당 돈방 면적은 0.18$m^2$, 0.23$m^2$ 및 0.30$m^2$로 하였고 돈군의 크기는 돈방당 15두, 20두 및 25두로 하였다. 일당증체량, 일당사료섭취량 및 사료요구율을 조사하였으며 자돈의 행동을 휴식, 섭취, 공격, 사회성 및 유희행동으로 나누어 조사분석하였으며 그 결과를 요약하면 다음과 같다. 1. 두당 돈방면적이 0.18$m^2$의 경우 사료섭취량은 많았으나(p<0.01) 증체량은 차이가 없고, 사료효율은 낮으므로(p<0.05) 두당 0.23$m^2$의 경우가 최적인 것으로 나타났다. 2. 돈군의 크기에 따른 자돈의 증체나 사료효율에는 차이가 없었으며 사료섭취량은 15두군이 가장 많았다(p<0.01). 3. 자돈의 두당 돈방면적은 행동에 크게 영향을 미치며 두당 돈방면적이 좁을수록 공격행동이 증가되었고, 휴식, 사회성 및 유희행동은 감소되었다(p<0.01). 4. 돈군의 크기는 자돈의 행동에 큰 영향을 미치지 않았으나, 유희행동은 돈군이 커질수록 감소되었다(p<0.01). 5. 자돈의 성장과 행동면에서 두당 0.23$m^2$의 돈방면적을 부여하고 20~25두 크기로 돈군을 유지하는 것이 최적인 것으로 나타났다.

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Effect of Inclusion of Hard Versus Soft Wheat Bran with Different Particle Size on Diet Digestibility, Growth Performance and Carcass Traits of Fattening Rabbits

  • Laudadio, V.;Dario, M.;Addonizio, F.;Tufarelli, Vincenzo
    • Asian-Australasian Journal of Animal Sciences
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    • 제22권10호
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    • pp.1377-1385
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    • 2009
  • Effect of inclusion of hard vs. soft wheat bran with different particle size on diet digestibility, growth performance and some slaughter traits was evaluated in fattening rabbits. Four isonitrogenous and isocaloric diets were used according to the origin of wheat bran (hard (HWB) - Triticum durum - and soft (SWB) - Triticum aestivum) combined with wheat bran particle size sieved by 2 mm (fine: 2) or by 8 mm (coarse: 8) in a bifactorial (2${\times}$2) study. A growth trial was conducted to measure the effect of treatments on performance in one hundred and twenty New Zealand White${\times}$Californian rabbits fed experimental diets from 50 to 87 days of age. Faecal apparent digestibility was determined within the last week in twenty animals per diet. Digestibility of nutrients was higher (p<0.05) in the diet containing HWB2, except for crude protein, ether extract and ash, than fine and coarse soft wheat bran diets. Final live weight, feed intake and feed consumption of rabbits on the diet with fine hard wheat bran were higher and resulted in greater daily weight gains (p<0.01) than for animals on the other diets. The slaughter yield and percentage value of organs were not significantly (p>0.05) affected by the diets fed; however, the diet containing fine hard wheat bran led to lower (p<0.05) percentages of skin, abdominal fat and carcass drip loss than the other dietary treatments. It is concluded that fine hard wheat bran can be better included in the diet than soft wheat bran to maximize growth performance without affecting carcass traits of fattening rabbits.