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61.
S. K. Shrivastava 《Software》1979,9(12):1001-1020
The programming language Concurrent Pascal has been extended to include some language features that facilitate the writing of fault-tolerant software. As a result, it is possible now to (1) write operating systems with a measure of fault-tolerance, and (2) for such an operating system to support fault-tolerant user programs. The paper describes these language features and illustrates their use with the help of a few working examples.  相似文献   
62.
This paper examines a concurrent process synchronization technique known as the conditional critical region method and suggests a simple improvement to it. This makes the method very attractive for inclusion in high-level programming languages allowing users to write parallel programs. Next, the paper describes an implementation of the technique and illustrates the use of the technique with the help of some well-known examples in parallel programming.  相似文献   
63.
Perovskite structure-based ceramic precursors have a characteristic property of substitution in the ‘A’ site of the ABO3 structure. This makes them a potential material for nuclear waste management in synthetic rock (Synroc) technology. In order to simulate the mechanism of rare earth fixation in perovskite, PrxCa1−xTiO3 (where x = 0.1) has been synthesized through ceramic route by taking calculated quantities of oxides of Ca, Ti and Pr as starting materials. The ceramic phase has been characterized by its powder diffraction pattern. The Rietveld analysis of the X-ray diffraction data has been carried out using GSAS software to achieve the convergence which gives the Rp = 5.74% and Rwp = 8.17%. The (h, k, l) values for different lattice planes have been calculated. The praseodymium substituted perovskite crystallizes in orthorhombic symmetry with space group: Pbnm, Z = 4. The unit cell parameters at room temperature are a = 5.39609(31) Å, b = 5.44869(30) Å and c = 7.6565(5) Å. The calculated and observed values of the corresponding intensities, 2θ and density of the polycrystalline powder show good agreement. GSAS-based calculation for bond distances TiO, CaO and bond angles OTiO, OCaO has been reported.  相似文献   
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66.
The internal electric field produced by a constant source impurity diffusion is calculated using Fermi-Dirac statistics for the majority carrier. Numerical results indicate that treating the material as if it were nondegenerate always produces an underestimate in the electric field. The field enhancement factor which gives the ratio of the effective diffusion coefficient to the impurity diffusion coefficient valid for a degenerate diffusion process is clarified.  相似文献   
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Hydrogen producing bacterial strain was isolated from Indian cow dung and identified of the bacterial family Enterobacteriaceae. This lab isolate was differentiated from Citrobacter Y-19 at molecular level by using RAPD, PCR based technique, and OPO-03460 and OPO-17800 RAPD marker for this specific strain (lab isolate) was identified. Fermentative studies were investigated for important parameters, starting with pH of the culture, temperature, inoculum age and inoculum volume, initial substrate concentration and different substrates. Among different substrates, dextrose and sucrose were the preferred substrates for hydrogen production. The optimal starting pH of the culture was found to be 5.0. The H2 production increased with increase in temperature up to 30 °C. The maximum value of H2 production was recorded when inoculum volume was 12.5% of the culture broth and inoculum age was 14 h. Under batch fermentation conditions, the maximum hydrogen production rate and yield were 355.2 ml l−1 h−1 and 2.1 mol/mol glucose (conversion 35%), respectively. These results indicate that this lab isolate is an ideal hydrogen producer.  相似文献   
69.
This paper presents a capacity planning model for the Indian aluminium industry based on a linear dynamic programming technique. The model has been used to analyse energy demand and CO2 emission for the period 1992–2021. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
70.
The influence of dietary levels of L ‐threonine (Thr) on growth and immune response was investigated in growing (0–5 weeks of age) Japanese quails (n = 288). Three dietary treatments were formulated using three levels of Thr [9.6, 10.2 and 11.2 kg?1 diet dry matter (DM)] at a fixed protein level of 233 g kg?1 and an energy level of 12.15 MJ (2900 kcal) metabolizable energy (ME) kg?1 feed dry matter. A metabolism trial with a 3‐day collection period was conducted at the third week of age employing all the birds. The cell‐mediated (using PHA‐P) and humoral (SRBC response) immune responses were measured at the fourth week of age. Carcass traits were assessed at the end of fifth week of age. Body weight gain was lower (P < 0.01) in birds received 9.6 g Thr kg?1 DM than in groups fed 10.2 g or 11.2 g kg?1 DM in the diet, but there was no significant difference in gain between the groups fed 10.2 or 11.2 g Thr kg?1 DM in the diet. Feed intake differed significantly owing to Thr levels being lowest (P < 0.05) at 9.6 g Thr kg?1 DM in the diet. Feed conversion ratio (FCR), protein efficiency and energy efficiency improved at the 11.2 g kg?1 level from 0 to 3 weeks of age; however, from 3 to 5 weeks of age, better FCR emanated from a diet with 9.6 g Thr kg?1 DM. The nitrogen balance did not differ (P > 0.05) with Thr level. Carcass traits, relative weight of immune organs and cell‐mediated (PHA‐P) and humoral (SRBC response) immune responses did not differ significantly (P > 0.05) as a result of the dietary treatments. Copyright © 2006 Society of Chemical Industry  相似文献   
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