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91.
A. Habib 《Building and Environment》1977,12(4):241-249
An analogue mechanism method, based in principle upon Newmark's spring bar mechanism technique, for the elastic analysis of rib-stiffened cylindrical barrels is presented. The shell column interaction is taken into account. Numerical solutions obtained for representative problems and their comparison, whenever possible, to existing solutions are presented. Experimental results obtained from a sand-cement model is presented in order to demonstrate the reliability of this method for predicting stresses in shell problems where there are no analytical solutions available for comparison. 相似文献
92.
EH Safar FM Abd-el Ghaffar SA Saffar KM Makled KS Habib R el Abiad E el Shabrawy 《Canadian Metallurgical Quarterly》1995,25(3):839-852
Infection by Toxoplasma gondii and Toxocara canis is getting much important nowadays. Both are soil transmitted infections. The present study was planned to detect the incidence of T. gondii and T. canis antibodies among 100 patients attending the outpatient clinics in Research Institutes of Ophthalmology (RIO), whose urine and stool were free from other parasitic stages. Patients were classified into two groups, group I; (70 ocular cases) and group II, (30 non-occular cases). Control group (group III); 30 healthy persons. Sera from all individuals were subjected to IFAT and IHAT to detect Toxoplasma antibodies and IFAT to detect Toxocara antibodies. By using IFAT for Toxoplasma revealed, 25% as a total incidence, 21.4% in group I, 33.3% in group II and 6.6% in group III. While IHAT revealed 51% as a total incidence, 51.4% in group I, 50% in group II and 23.3% in group III. Among group I, retinochoroiditis cases showed the highest incidence and titre. While hydrocephalic cases showed highest incidence and titre in group II. T. canis antibodies revealed 23% as a total incidence, 14.3% in group I, 43.3% in group II and 5% in group III. Cases presented with retinal detachment showed the highest incidence and titre in group I while in group II hepatomegalic cases gave the highest incidence and titre. Concomitant infection of both Toxoplasma and Toxocara was detected in 8% of positive cases. 相似文献
93.
To determine the potential differences in the effect of various nutrients on lipid peroxidation, the ethane exhalation (EE) rate, an index of lipid peroxidation, was measured in rats at 4 (young), 18 (intermediate age), and 24 (aged) mo of age at fasting conditions and after acute ingestion of various test meals. The EE rate (means +/- SD) after a 15-h fast was significantly reduced in 24-mo-old rats (2.45 +/- 0.44 pmol.min-1.100 g body wt-1) and 18-mo-old rats (3.51 +/- 0.55 pmol.min-1.100 g body wt-1) compared with 4-mo-old rats (4.44 +/- 0.66 pmol.min-1.100 g body wt-1; P < 0.01). The EE rate significantly increased in 4-mo-old rats after ingestion of 50% (wt/vol) dextrose (8.59 +/- 2.9 pmol.min-1.100 g body wt-1), 50% casein hydrolysate (6.77 +/- 1.23 pmol.min-1.100 g body wt-1), and 20% neutral lipid emulsion (7.33 +/- 1.96 pmol.min-1.100 g body wt-1; P < 0.01). The response of aged rats to these nutrients compared with young rats was reduced by approximately 50%. A 25% dextrose solution or a 50% solution of sucrose, fructose, maltose, or galactose did not significantly alter EE rate. It is concluded that various macronutrients have a diverse potential of inducing lipid peroxidation. The responsiveness of aged rats to meal-induced enhancement of EE and presumably lipid peroxidation is significantly reduced. 相似文献
94.
A mixture of five new ceramides was isolated from the aerial parts of Rantherium suaveolens and characterized by spectroscopic and chemical methods. Their structures were elucidated by spectroscopic and chemical methods
as (2S, 3S, 4R, 2′R, 14E)-2-(2′-hydroxydocosanoylamino)-14-octadecene-1,3,4-triol (1), (2S,3S,4R,2′R, 14F)-2-(2′-hydroxytricosanoylamino)-14-octadecene-1,3,4-triol (2), (2S,3S,4R,2′R,14F)-2-(2′-hydroxytetracosanoylamino)-14-octadecene-1,3,4-triol (3), (2S,3S,4R,2′R,14E)-2-(2′-hydroxypentacosanoylamino)-14-octadecene-1,3,4-triol (4), and (2S,3S,4R,2′R,14E)-2-(2′-hydroxyhexacosanoylamino)-14-octadecene-1,3,4-triol (5). 相似文献
95.
This study compares the thermal efficiency and economics of using oxygen rather than air as the oxidant in large coal-fired MHD-steam energy conversion plants, using a computer model to calculate thermal efficiency. The systems compared are a coal-air system with a thermal input of 2000 MWth and two coal-oxygen systems, one with an input of 2000 MWth and one with 6600 MWth. The paper describes the process; compares flame temperature, electrical conductivity, and specific enthalpy; and presents Mollier diagrams for the two systems. At an oxidant preheat temperature of 1644 K, the net thermal efficiency of the coal-oxygen system is 8 to 9 percentage points lower than that for the coal-air system, if the power required to produce the oxygen is taken into account; however, despite its lower thermal efficiency, the coal-oxygen system has a lower cost of electricity. At a preheat temperature of 1644 K, the cost advantage is small, but at temperatures below 1200 K, the cost advantage is significant. 相似文献
96.
Sami J. Habib 《International Journal of Network Management》2008,18(1):1-13
We present a redesign methodology that automatically redesigns a network topology while considering the different network technology interfaces. The network redesign problem is to preserve as many as possible of the network devices within the original network topology to satisfy the redesign factors while minimizing the redesign cost and time. The redesign factors can be various parameters that are involved in the design of a network topology, such as the workload and number of clients. In this paper we used a uniform growth of the network workload as the main factor for topology redesign; moreover, our methodology attempts to maintain as many as possible of the network devices within the original topology while satisfying the extra growth of the clients' loads. We formulated the network redesign problem as an optimization problem and used an evolutionary approach to search the redesign space. The experimental results for a three‐level network redesign problem described here demonstrate how valuable the redesign methodology is in finding good solutions with low redesign cost and short redesign time for an enterprise networks consisting of 65 client nodes. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
97.
Ghulam Gilanie Usama Ijaz Bajwa Mustansar Mahmood Waraich Zulfiqar Habib 《International journal of imaging systems and technology》2019,29(3):260-271
The drive of this study is to develop a robust system. A method to classify brain magnetic resonance imaging (MRI) image into brain-related disease groups and tumor types has been proposed. The proposed method employed Gabor texture, statistical features, and support vector machine. Brain MRI images have been classified into normal, cerebrovascular, degenerative, inflammatory, and neoplastic. The proposed system has been trained on a complete dataset of Brain Atlas-Harvard Medical School. Further, to achieve robustness, a dataset developed locally has been used. Extraordinary results on different orientations, sequences of both of these datasets as per accuracy (up to 99.6%), sensitivity (up to 100%), specificity (up to 100%), precision (up to 100%), and AUC value (up to 1.0) have been achieved. The tumorous slices are further classified into primary or secondary tumor as well as their further types as glioma, sarcoma, meningioma, bronchogenic carcinoma, and adenocarcinoma, which could not be possible to determine without biopsy, otherwise. 相似文献
98.
Farida khan Naeem A Israf Ud Din T. Saeed Mshari A. Alotaibi Abdulrahman I. Alharthi Asad Habib Tabassum Malik 《Ceramics International》2021,47(4):4749-4757
In the present study, hexagonal boron nitride (h-BN) was synthesized from boric acid and melamine by thermal annealing method in a nitrogen atmosphere. The pure h-BN was used as an efficient sorbent for the uptake of Cd2+ ions from the solution phase. The kinetics and sorption studies of metal ions onto the h-BN were carried out in batch adsorption experiments at different temperature, time, pH, sorbent dosage, and concentration of metal ions. The optimum pH for the removal of the Cd2+ ions was found to be pH 7. The effect of temperature showed that the process of Cd2+ sorption remained endothermic in the range of 298 K–328 K. The Lagergren's first and Ho's second kinetic models were tested to interpret the adsorption kinetic data, however the present data was explained well by Ho's model for kinetics. The thermodynamic perameters ΔG, ΔS and ΔH were determined using the available adsorption data at different temperatures. The physicochemical properties of the synthesized product were also characterized before and after adsorption by different analytical techniques like FT-IR, TGA, XRD and Point of Zero Charge (PZC). The morphology of the surface was analyzed with the help of Scanning Electron Microscopy. The h-BN proved to be an efficient adsorbent for the uptake of the Cd2+ ions from aqueous media. 相似文献
99.
100.
Habib Abdulrahman Prybutok Victor R. Philpot Denise 《Information Systems and E-Business Management》2022,20(1):1-25
Information Systems and e-Business Management - In the past decade, cities around the world have published their open data as a new service. Some have used this service innovatively, as a vehicle... 相似文献