368 research outputs found
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Flow coupling during three-phase gravity drainage
We measure the three-phase oil relative permeability k(ro) by conducting unsteady-state drainage experiments in a 0.8 m water-wet sand pack. We find that when starting from capillary-trapped oil, k(ro) shows a strong dependence on both the flow of water and the water saturation and a weak dependence on oil saturation, contrary to most models. The observed flow coupling between water and oil is stronger in three-phase flow than two-phase flow, and cannot be observed in steady-state measurements. The results suggest that the oil is transported through moving gas-oil-water interfaces (form drag) or momentum transport across stationary interfaces (friction drag). We present a simple model of friction drag which compares favorably to the experimental data.University of Texas at AustinCenter for Frontiers of Subsurface Energy SecurityUS Department of Energy, Office of Basic Energy Sciences DE-SC0001114Petroleum and Geosystems Engineerin
Using Machine Learning for Land Suitability Classification
Artificial intelligence and machine learning methods can be used to automate the land suitability classification. Multiple Classifier System (MCS) or ensemble methods are rapidly growing and receiving a lot of attention and proved to be more accurate and robust than an excellent single classifier in many fields. In this study a dataset based land suitability classification is addressed. It is done using a newly proposed ensemble classifier generation technique referred to as RotBoost, which is constructed by combining Rotation Forest and AdaBoost, and it is known to be the first time that RotBoost has been applied for suitability classification. The experiments conducted with the study area, Shavur plain, lies in the northern of Khuzestan province, southwest of Iran. It should be noted that suitability classes for the input data were calculated according to FAO method. This provides positive evidence for the utility of machine learning methods in land suitability classification especially MCS methods. The results demonstrate that RotBoost can generate ensemble classifiers with significantly higher prediction accuracy than either Rotation Forest or AdaBoost, which is about 99% and 88.5%, using two different performance evaluation measures
Chitinase isolated from water and soil bacteria in shrimp farming ponds
Chitinases have received attention because of their wide applications in the medicine, biotechnology, agriculture, waste management and industrial applications such as food quality enhancer and biopesticide. Excessive use of insecticides has led to several problems related to pollution and environmental degradation. In this study, isolation and identification of native bacterial strains with chitin hydrolysis activity, took place from water and soil of shrimp culture ponds in Bushehr and Abadan. To investigate the capacity of our chitinase for using in insecticide, biochemical properties of selected chitinase obtained in this research were compared to that of produced by Bacillus cereus p-1, isolated from an insecticide tablet. In this research, three mesophilic strains containing: Serratia marcescens B4A, Citrobacter freundii B1A and Bacillus cereus B3R were isolated. Results showed a 1600 bp band corresponding to chitinase gene. The similarity between temperature and pH profile and stability of chitinase was extracted from native bacteria and ones was obtained from Bacillus cereus p-1 implied that chitinase extracted from Serratia marcescens B4A has potential application in industry
Effects of feeding strategy, fiber source of the diet, and crude protein content on productive performance of broiler breeder hens
A 12-wk experiment was conducted to investigate the effect of feeding program, dietary fiber, and CP content of the diet on productive performance of Ross broiler breeder hens (41 wk of age). There were 12 treatments arranged factorially with 2 levels of CP (14.5 vs. 17.4%), 3 fiber sources (0 vs. 3% inulin vs. 3% cellulose), and 2 levels of feed intake (160 vs. 208 g/d) that corresponded to restricted (R) or ad libitum (AL) feeding systems. The experimental diets contained 2,800 kcal ME with either 0.65 (14.5% CP) or 0.78% Lys (17.4% CP)
Efectos de la inclusión de trigo y suplementación con xilanasas del pienso sobre la actividad enzimática intestinal, la retención de los nutrientes y la productividad en gallinas de 25 a 33 semanas de edad
El trigo es un cereal rico en xilanos lo que reduce su potencial en piensos para aves de puesta por su efecto perjudicial sobre la digestibilidad y el porcentaje de huevos sucios (Lázaro et al., 2003). La utilización de xilanasas podría resolver esta problemática y mejorar la productividad de las aves. Diversos autores (Gracia et al., 2003) han estudiado los efectos de la inclusión de xilanasas en el pienso sobre la digestibilidad de los nutrientes y la productividad (Gutiérrez-Álamo et al., 2008). Sin embargo, sus efectos sobre la producción de enzimas endógenas y el pH de los diversos segmentos del tracto gastrointestinal (TGI) han sido poco estudiados. El objetivo de este ensayo fue estudiar la inclusión de una variedad de trigo de alto contenido en xilanos sobre diversas variables digestivas y la productividad en aves de puesta blancas
Sodium Valproate and Phenobarbitol: Weight Complications of Treatment in Epileptic Children
Objective The aim of this study was to evaluate and compare the effects of Na Valproate and Phenobarbital on changes in the weight of epileptic patients following treatment for their condition using the drugs mentioned.Materials and methodsSixty epileptics were assigned into two groups of 30 patients each, the case and controls. The diagnosis was made on the basis of the International League Against Epilepsy (ILAE) characteristics. BMI was defined. In the case group, the patients received 20mg/kg/day of Na Valproate, while the 30 controls received 5mg/kg/day of Phenobarbital for 6 months. Using the Mc Nemar and Chi-2 tests, BMI changes were compared after 6 months between the groups. Fisher's exact test was used to evaluate the role of age, sex, and primary weight on the weight increase due to Na Valproate usage.ResultsThere were no specific changes in age, sex, primary BMI and fatness between the 2 groups; in the case group, 20 patients(66.7%) and in the controls 4(13.3%) gained weight (PConclusionThe results indicate that epileptic children, aged over 10 years, and those who are overweight have more chances of gaining weight or becoming fatter, following treatment with Na Valproate. Further studies investigating the issue are warranted
Effect of wheat inclusion and xylanase supplementation of the diet on intestinal enzyme activity, nutrient retention and performance in laying hen from 25 to 47 wks of age
A trial was conducted to examine the effects of increasing levels of wheat in the diet and xylanase (ES) supplementation on nitrogen and ether extract retention, pH of the GIT, productive performance from 25 to 47 wks of age, and enzyme activity at the small intestine level. The basal diets (from 25 to 33 wks and from 33 to 47 wks) consisted of soybean meal and corn, and the wheat was introduced in the experimental diets at expenses of corn, primarily
Fabrication and characterization of flexible spray-coated antennas
This paper investigates the potential of using spray coating as a methodology for flexible antenna fabrication. The methodology has advantages compared with other antenna-printing techniques, such as screen-printing and gravure printing (more flexibility in design), or inkjet printing (faster production). The methodology is demonstrated using two different types of folded dipole antennas that are designed to operate in the ultra-high frequency radio-frequency identification (UHF RFID) band. Both antennas show good agreement between simulation and measurement of the spray-coated samples in terms of power reflection coefficient and gain. The two folded dipoles, with and without ground plane, show comparable performance in terms of gain, as similar antennas found in literature. The folded dipole on a ground plane is more stable near conductive surfaces and on the human body. Given these results, we conclude that spray coating is a good technique for printing small to medium sized batches of antennas
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