913 resultados para multiple simultaneous equation models


Relevância:

100.00% 100.00%

Publicador:

Resumo:

A brief review is given of turbulence models in use today for engineering applications. The main categories covered are simple eddy-viscosity models, the k-ε two-equation model and Reynolds-stress-equation models as well as their algebraic stress derivatives. Calculation examples are presented for a variety of 2D and 3D flows.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Changing the sample's temperature from 200 K to 535 K, we observed 670-fold enhancement of a phonon-assisted upconversion emission at ≈754 nm obtained from a Nd3+-doped tellurite glass excited by 5 ns laser pulses at 805 nm. A rate-equation model, including the relevant energy levels and temperature dependent transition rates, is proposed to describe the process. The results fit well with the data when one considers the nonradiative transitions contributing for the 754 nm luminescence are promoted by an effective phonon mode with energy of 700 cm-1. © 2013 American Institute of Physics.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The objective of this study was to estimate genetic parameters for female mature weight (FMW), age at first calving (AFC), weight gain from birth to 120 days (WG_B_120), from 210 to 365 days (WG_210_365), rib eye area (REA), back fat thickness (BF), rump fat (RF) and body weight at scanning date (BWS) using single and multiple-trait animal models by the REML method from Nellore cattle data. The estimates of heritability ranged from 0.163±0.011 for WG_210_365 to 0.309±0.028 for RF using the single-trait model and from 0.163±0.010 for WG_210_365 to 0.382±0.025 for BWS using the multiple-trait model. The estimates of genetic correlations ranged from -0.35±0.08 between AFC with BF to 0.69±0.04 between WG_B_120 with BWS. Selection for weights gains, REA, and BWS can improve FMW. © 2013 Elsevier B.V.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Pós-graduação em Genética e Melhoramento Animal - FCAV

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

ObjectiveFindings on weight training and waist circumference (WC) change are controversial. This study examined prospectively whether weight training, moderate to vigorous aerobic activity (MVAA), and replacement of one activity for another were associated with favorable changes in WC and body weight (BW).MethodsPhysical activity, WC, and BW were reported in 1996 and 2008 in a cohort of 10,500 healthy U.S. men in the Health Professionals Follow-up Study. Multiple linear regression models (partition/substitution) to assess these associations were used.ResultsAfter adjusting for potential confounders, a significant inverse dose-response relationship between weight training and WC change (P-trend<0.001) was observed. Less age-associated WC increase was seen with a 20-min/day activity increase; this benefit was significantly stronger for weight training (-0.67 cm, 95% CI -0.93, -0.41) than for MVAA (-0.33 cm, 95% CI -0.40, -0.27), other activities (-0.16 cm, 95% CI -0.28, -0.03), or TV watching (0.08 cm, 95% CI 0.05, 0.12). Substituting 20 min/day of weight training for any other discretionary activity had the strongest inverse association with WC change. MVAA had the strongest inverse association with BW change (-0.23 kg, 95% CI -0.29, -0.17).ConclusionsAmong various activities, weight training had the strongest association with less WC increase. Studies on frequency/volume of weight training and WC change are warranted.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In the pumping pipelines the located load losses are very important since they have direct influence on hydraulic design of an irrigation system, especially regarding the concentric reducers used in the distribution lines. Hence this work was conducted in the Laboratório de Hidráulica do Centro Federal de Educação Tecnológica de Uberaba. We analyzed 03 concentric reducers PVC 75 x 50 mm, 50 mm and 35 x 35 x 1 "operating at different flow rates. The performance of the tests with the variation of flow in every situation possible to obtain equations to estimate the loss. The equation models presented a high setting, thus enabling the determination of the localized head loss in a situation closer to field reality. For the reduction of 75 x 50 x 35 mm and 50 mm at a flow rate 16.97 m³ h-1 the pressure drop reduction was obtained respectively 0.9263 and 2.7408 mca. To the reduction of 35 x 1 "at a flow rate of 6.02 m³ h-1 was obtained 2.9304 mca pressure drop reduction. The located losses produced by these reductions are relatively high and should be considered with great discretion in hydraulic design of the irrigation system.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

We used body mass index (BMI) and waist circumference (WC) as fat indicators to assess whether perinatal and early adulthood factors are associated with adiposity in early adulthood. We hypothesized that risk factors differ between men and women and are also different when WC is used for measuring adiposity as opposed to BMI. We conducted a longitudinal study based on a sample of 2,063 adults from the 1978/1979 Ribeirao Preto birth cohort. Adjustment was performed using four sequential multiple linear regression models stratified by sex. Both perinatal and early adulthood variables influenced adulthood BMI and WC. The associations differed between men and women and depending on the measure of abdominal adiposity (BMI or WC). Living with a partner, for both men and women, and high fat and alcohol intake in men were factors that were consistently associated with higher adulthood BMI and WC levels. The differences observed between sexes may point to different lifestyles of men and women, suggesting that prevention policies should consider gender specific strategies.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

As part of the international CUPID investigation, we compared physical and psychosocial risk factors for musculoskeletal disorders among nurses in Brazil and Italy. Using questionnaires, we collected information on musculoskeletal disorders and potential risk factors from 751 nurses employed in public hospitals. By fitting country-specific multiple logistic regression models, we investigated the association of stressful physical activities and psychosocial characteristics with site-specific and multisite pain, and associated sickness absence. We found no clear relationship between low back pain and occupational lifting, but neck and shoulder pain were more common among nurses who reported prolonged work with the arms in an elevated position. After adjustment for potential confounding variables, pain in the low back, neck and shoulder, multisite pain, and sickness absence were all associated with somatizing tendency in both countries. Our findings support a role of somatizing tendency in predisposition to musculoskeletal disorders, acting as an important mediator of the individual response to triggering exposures, such as work-load.