• 제목, 요약, 키워드: NRC-2001 Model

검색결과 8건 처리시간 0.031초

Model Prediction of Nutrient Supply to Ruminants from Processed Field Tick Beans

  • Yu, P.;Christensen, D.A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.12
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    • pp.1674-1680
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    • 2004
  • The objective of this study was to compare the Dutch DVE/OEB system and the NRC-2001 model in the prediction of supply of protein to dairy cows from processed field tick beans. Comparisons were made in terms of 1) ruminally synthesized microbial CP, 2) truly absorbed protein in the small intestine, and 3) degraded protein balance. The results showed that the predicted values from the DVE/OEB system and the NRC-2001 model had significant correlations with high R (>0.90) values. However, using the DVE/OEB system, the overall average microbial protein supply based on available energy was 16% higher and the truly absorbed protein in the small intestine was 9% higher than that predicted by the NRC-2001 model. The difference was also found in the prediction of the degraded protein balances (DPB), which was 5% lower than that predicted based on data from the NRC-2001 model. These differences are due to considerably different factors used in calculations in the two models, although both are based on similar principles. It need to mention that this comparison was based on the limited data, the full comparison involving various types of concentrate feeds will be investigated in the future.

면진된 집중질량 보 모델의 지진응답해석 (Seismic Response Analysis of a Isolated Lumped-Mass Beam Model)

  • 이재한;구경회
    • 한국전산구조공학회:학술대회논문집
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    • pp.561-568
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    • 2001
  • For obtaining the time history nodal responses of reactor building, a lumped-mass beam model composed of two sticks for the reactor building and the reactor support structure is developed. The time history responses for the non-isolated and isolated reactor buildings are calculated under an artificial time history, generated using the seismic spectrum curve of US NRC RG1.60. The analysis results show that the horizontal accelerations of the isolated building are dramatically decreased to one-tenths of the non-isolated one, but the vertical responses are increased by about 40%.

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Modeling Nutrient Supply to Ruminants: Frost-damaged Wheat vs. Normal Wheat

  • Yu, Peiqiang;Racz, V.
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.3
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    • pp.333-339
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    • 2010
  • The objectives of this study were to use the NRC-2001 model and DVE/OEB system to model potential nutrient supply to ruminants and to compare frost damaged (also called "frozen" wheat with normal wheat. Quantitative predictions were made in terms of: i) Truly absorbed rumen synthesized microbial protein in the small intestine; ii) Truly absorbed rumen undegraded feed protein in the small intestine; iii) Endogenous protein in the digestive tract; iv). Total truly absorbed protein in the small intestine; and v). Protein degraded balance. The overall yield losses of the frozen wheat were 24%. Results showed that using the DVE/OEB system to predict the potential nutrient supply, the frozen wheat had similar truly absorbed rumen synthesized microbial protein (65 vs. 66 g/kg DM; p>0.05), tended to have lower truly absorbed rumen undegraded feed protein (39 vs. 53 g/kg DM; p<0.10) and had higher endogenous protein (14 vs. 9 g/kg DM; p<0.05). Total truly absorbed protein in the small intestine was significantly lower (89 vs. 110 g/kg DM, p<0.05) in the frozen wheat. The protein degraded balance was similar and both were negative (-2 vs. -1 g/kg DM). Using the NRC-2001 model to predict the potential nutrient supply, the frozen wheat also had similar truly absorbed rumen synthesized microbial protein (average 56 g/kg DM; p>0.05), tended to have lower truly absorbed rumen undegraded feed protein (35 vs. 48, g/kg DM; p<0.10) and had similar endogenous protein (average 4 g/kg DM; p>0.05). Total truly absorbed protein in the small intestine was significantly lower (95 vs. 108 g/kg DM, p<0.05) in the frozen wheat. The protein degraded balance was not significantly different and both were negative (-16 vs. -19 g/kg DM). In conclusion, both models predict lower protein value and negative protein degraded balance in the frozen wheat. The frost damage to the wheat reduced nutrient content and availability and thus reduced nutrient supply to ruminants by around 12 to 19%.

Prediction of Dry Matter Intake in Lactating Holstein Dairy Cows Offered High Levels of Concentrate

  • Rim, J.S.;Lee, S.R.;Cho, Y.S.;Kim, E.J.;Kim, J.S.;Ha, Jong K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.5
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    • pp.677-684
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    • 2008
  • Accurate estimation of dry matter intake (DMI) is a prerequisite to meet animal performance targets without penalizing animal health and the environment. The objective of the current study was to evaluate some of the existing models in order to predict DMI when lactating dairy cows were offered a total mixed ration containing a high level of concentrates and locally produced agricultural by-products. Six popular models were chosen for DMI prediction (Brown et al., 1977; Rayburn and Fox, 1993; Agriculture Forestry and Fisheries Research Council Secretariat, 1999; National Research Council (NRC), 2001; Cornell Net Carbohydrate and Protein System (CNCPS), Fox et al., 2003; Fuentes-Pila et al., 2003). Databases for DMI comparison were constructed from two different sources: i) 12 commercial farm investigations and ii) a controlled dairy cow experiment. The model evaluation was performed using two different methods: i) linear regression analysis and ii) mean square error prediction analysis. In the commercial farm investigation, DMI predicted by Fuentes-Pila et al. (2003) was the most accurate when compared with the actual mean DMI, whilst the CNCPS prediction showed larger mean bias (difference between mean predicted and mean observed values). Similar results were observed in the controlled dairy cow experiment where the mean bias by Fuentes-Pila et al. (2003) was the smallest of all six chosen models. The more accurate prediction by Fuentes-Pila et al. (2003) could be attributed to the inclusion of dietary factors, particularly fiber as these factors were not considered in some models (i.e. NRC, 2001; CNCPS (Fox et al., 2003)). Linear regression analysis had little meaningful biological significance when evaluating models for prediction of DMI in this study. Further research is required to improve the accuracy of the models, and may recommend more mechanistic approaches to investigate feedstuffs (common to the Asian region), animal genotype, environmental conditions and their interaction, as the majority of the models employed are based on empirical approaches.

신규 조사료원 사료용 벼 사일리지의 사료가치 평가 및 급여 비율에 따른 반추위 발효성상 비교 (Evaluation the Feed Value of Whole Crop Rice Silage and Comparison of Rumen Fermentation according to Its Ratio)

  • 박설화;백열창;이슬;김병현;류채화
    • 한국초지조사료학회지
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    • v.40 no.4
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    • pp.236-243
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    • 2020
  • 본 연구는 사료용 벼 사일리지의 사료가치를 평가하고 반추위 발효성상을 이용하여 사료용 벼 사일리지와 배합사료의 적정 비율을 조사하고자 하였다. 사료가치 평가는 AOAC(2019)에 따라 분석하였고, 영양소 소화율 예측은 NRC(2001)의 수식을 기반으로 산출하였다. In vitro 반추위 발효시험은 총 6개의 시험구로 구성되었고, 반추위 pH, 가스생성량, 암모니아태 질소 및 휘발성 지방산을 측정하였다:T1(100:0), T2(60:40), T3(40:60), T4(20:80), T5(10:90), T6(0:100). 영양소 소화율 시험에서는 사료용 벼 사일리지 비율에 따라 40:60(W40), 20:80(W20) 및 10:90(W10)로 나누어 수행하였다. 사료용 벼 사일리지의 조단백질, 조지방 및 NDF 함량은 각각 12.29%, 1.67%, 59.79%로 측정되었다. 또한 NRC(2001)을 이용한 사료용 벼 사일리지의 TDN 예측 결과는 51.49%로 나타났다. 반추위 발효 in vitro 결과, 가스생성량과 총 휘발성 지방산생성량은 T4, T5 및 T6에서 다른 시험구보다 유의적으로 높았다(p<0.05). 초산과 AP ratio도 T4, T5 및 T6에서 유의적으로 높게 나타났다(p<0.05). 프로피온산 및 낙산에서는 사료용 벼 사일리지와 배합사료의 비율의 변화에 따라 유의적인 차이를 보였다(p<0.05). 건물 및 조단백 소화율은 W40에서 유의적으로 낮은 결과를 보였으나(p<0.05), W20 및 W10은 유의적 차이가 없었다. 따라서 사료용 벼 사일리지는 사료로서 가치가 있다고 판단된다. 또한, 사료용 벼 사일리지와 배합사료의 급여비율을 20:80하는 것이 반추위 발효 및 영양소 소화를 저해하지 않는 수준에서 농가의 경제성에도 긍정적일 것으로 생각된다.

참나무류와 리기다소나무 간벌재를 이용한 목질 조사료 제조 및 사료가치 평가 (Manufacturing and Feed Value Evaluation of Wood-Based Roughage Using Lumber from Thinning of Oak and Pitch Pine)

  • 김석주;이성숙;백열창;김용식;박미진;안병준;조성택;최돈하
    • 목재공학
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    • v.43 no.6
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    • pp.851-860
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    • 2015
  • 참나무류와 리기다소나무 간벌재 칩을 사용하여 각각 60, 90, 120분 동안 증기 가열(증해) 처리하여 조사료를 제조하고 정유 함량을 비교하였다. 두 수종 모두 증해 처리 시간이 증가됨에 따라 정유 함량이 감소하였으며, 90분과 120분 처리했을 때 $0.1m{\ell}/kg$ 이하의 정유 함량을 보였다. 90분 증해 처리하여 제조된 조사료의 사료로써의 가치를 화학성분 조성, NRC (National Research Counsil) 모델링, 반추위 소화율, 영양성분 대비 상대적 경제 가치 분석을 통해 평가하였다. 참나무류 조사료의 DM (dry matter; 건물), CP (crude protein; 조단백), EE (ether extract; 조지방), NDF (neutral detergent fiber; 중성세제섬유소), ADF (acid detergent fiber; 산성세제섬유소), ADL (acid detergent lignin; 산성세제리그닌), NFC (nonfiber carbohydrate; 비섬유소탄수화물) 함량은 각각 95.4, 1.36, 3.11, 90.05, 83.85, 17.33, 6.50 %로 측정되었고, 리기다소나무 조사료는 각각 94.37, 1.33, 5.48, 87.89, 86.88, 30.56, 6.32%로 측정되었다. NRC 모델링을 이용한 영양평가에서는 참나무류 조사료가 TDN (total digestible nutrient) 40.55%, DE (digestible energy) 1.79 Mcal/kg이었고 리기다소나무 조사료가 TDN 31.22%, DE 1.38 Mcal/kg으로 나타나 참나무류 조사료가 더 높은 영양가를 가진 것으로 사료되었다. 반추위 내 건물소화율은 참나무류 조사료(18.07%)가 리기다소나무 조사료(10.02%)보다 높았다. 영양성분 대비 상대적 경제 가치는 참나무류 조사료는 235원, 리기다소나무 조사료는 210원으로 나타났다.

원자력발전소의 Main Control Boards에 대한 내진 해석 (Seismic Analysis of the Main Control Boards for Nuclear Power Plant)

  • Byeon, Hoon-Seok;Lee, Joon-Keun;Kim, Jin-Young
    • 한국소음진동공학회:학술대회논문집
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    • pp.498-498
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    • 2001
  • Seismic qualification of the Main Control Boards for nuclear power plants has been performed with the guideline of AS ME Section III. US NRC Reg. Guide and IEEE 344 code. The analysis model of the Main Control Boards is consist of beam. shell and mass element by using the finite element method. and, at the same time. the excitation forces and other operating loads for each model are encompassed with respect to different loading conditions. As the fundamental frequencies of the structure are found to be less than 33Hz. which is the upper frequency limit of the seismic load, the response spectrum analysis using ANSYS is performed in order to combine the modal stresses within the frequency limit. In order to confirm the structural and functional integrity of the major components, modal analysis theory is adopted to derive the required response spectrum at the component locations. As all the combined stresses obtained from the above procedures are less than allowable stresses and no mechanical or electrical failures are found from the seismic testing, it concludes the Main Control Boards is dynamically qualified for seismic conditions. Although the authors had confirmed the structural and functional integrity of both Main Control Boards and all the component, in this paper only the seismic analysis of the Main Control Board is introduced.

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Responses of Dairy Cows to Supplemental Highly Digestible Rumen Undegradable Protein and Rumen-protected Forms of Methionine

  • Sun, T.;Yu, X.;Li, S.L.;Dong, Y.X.;Zhang, H.T.
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.5
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    • pp.659-666
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    • 2009
  • Metabolizable protein (MP) supply and amino acid balance in the intestine were manipulated through selection of highly digestible rumen-undegradable protein (RUP) sources and protected methionine (Met) supplementation. Four ruminallycannulated, multiparous Holstein cows averaging 193${\pm}$13 days in milk were used in a 4${\times}$4 Latin square design to assess N utilization and milk production responses to changes in RUP level, post-ruminal RUP digestibility and protected Met supplementation. Treatments were A) 14.0% crude protein (CP), 8.0% rumen degradable protein (RDP) and 6.0% RUP of low intestinal digestibility (HiRUP-LoDRUP); B) 14.1% CP, 8.1% RDP and 6.0% RUP of high intestinal digestibility (HiRUP-HiDRUP); C) 13.1% CP, 7.9% RDP and 5.2% RUP of high intestinal digestibility (LoRUP-HiDRUP), and D) 13.1% CP, 7.9% RDP and 5.2% RUP of high intestinal digestibility plus rumen escape sources of Met (LoRUP-HiDRUP+Met). Experimental diets were formulated to have similar concentrations of RDP, net energy of lactation ($NE_L$), neutral detergent fiber (NDF), acid detergent fiber (ADF), calcium, phosphorus and ether extract using the NRC model (2001). Results showed that dry matter intake (DMI), production of milk fat and protein were similar among treatments. Milk production was similar for diet HiRUP-LoDRUP, HiRUP-HiDRUP and LoRUP-HiDRUP+Met, and significantly higher than diet LoRUP-HiDRUP. Milk fat and protein percentage were higher for cows receiving HiDRUP treatments, with the greatest increases in the diet LoRUP-HiDRUP+Met. There was no significant change in ruminal pH, $NH_3g-N$ and volatile fatty acid (VFA) concentration among all treatments. Apparent digestibility of dry matter (DM), CP, NDF and ADF and estimated bacterial CP synthesis were similar for all treatments. Nitrogen intakes, blood and milk urea-N concentrations were significantly higher for cows receiving HiRUP diets. Urine volume and total urinary N excretion were significantly lowered by LoRUP diets. Lowering dietary RUP level while supplementing the highly digestible RUP source with rumen escape sources of Met resulted in similar milk production, maximal milk fat and protein concentration and maximum N efficiency, indicating that post-ruminal digestibility of RUP and amino acid balance in the small intestine can be more important than total RUP supplementation.