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1.
Forty paediatric cases of A.R.F. (Acute Renal Failure) of various aetiology were included in the study. 60% of patients were less than 4 years of age with male predominance. 80% cases reported to us very late with oligoanuria of more than 24 hours (2-7 days). Diarrhoea, vomiting and fever were other dominant symptoms. Maximum cases were severely anaemic (87.5%) with mean Hb 7.73 +/- 1.9 gm%. 40% cases were of underweight while only one case (2.5%) was of over weight, inspite of volume excess in 40% cases. All 24 cases, who were estimated for serum albumin, found to have marked hypoalbuminemia. Mortality was found to be as high as 65% inspite of effective peritoneal dialysis in all cases. High mortality seems to be due to profound anuria of many days (because of marked delay in reaching the hospital), fever and malnutrition besides other factors as aetiology. 相似文献
2.
This paper presents and studies the Canadian Truck Driver Scheduling Problem (CAN-TDSP), which is the problem of determining whether a sequence of locations can be visited within given time windows in such a way that driving and working activities of truck drivers comply with Canadian Commercial Vehicle Drivers Hours of Service Regulations. Canadian regulations comprise the provisions found in US hours of service regulations as well as additional constraints on the maximum amount of driving and the minimum amount of off-duty time on each day. We present two heuristics and an exact approach for solving the CAN-TDSP. Computational experiments demonstrate the effectiveness of our approaches and indicate that Canadian regulations are significantly more permissive than US hours of service regulations. 相似文献
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A comparison of the rates of substitution and elimination reactions occuring simultaneously in alkaline hydrolysis of n-amyl chloride, isoamyl chloride, n-amyl iodide and n-hexyl iodide at different temperatures and in varying alcohol-water mixtures, has been made. Under the same conditions the rates of solvolysis of these halides have also been reported. In the case of n-amyl halides there is a much larger rate difference between chloride and bromide than between bromide and iodide. 相似文献
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Presented here in the framework of the generalized BCS equations??which are based on multiple phonon exchanges for the formation of Cooper pairs (CPs)??is continuation of a study carried out earlier for MgB2 Nb3Sn and YBCO. Addressed now are the principal members of the Tl- and Bi-based high-T c superconductors. For any of these, with the input of any two parameters from the set {critical temperature, two gaps}, and the Debye temperature, it is shown that one can calculate the remaining parameter. This is similar to what normal BCS equations achieve for a simple superconductor. Further, we show that these equations lead to upper bounds on the gap- and the T c -values of a HTSC, beyond which one must invoke 2/3-phonon mechanism for the formation of CPs. Our considerations suggest the interesting possibility that senior members of the said families of cuprates may be three-gap SCs. 相似文献
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Wireless Personal Communications - A VANET is an excellent instance of a wireless sensor network. The mobile vehicles are the nodes and communication happens between the vehicular nodes. This... 相似文献
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This paper considers the analysis of a single server n-similar unit system. Initially k(<n) units form an orbit which functions if one unit functions at a time and the remaining n − k units work as cold standbys. When a unit fails in the orbit it is instantaneously replaced by one of the standbys with the help of a perfect transfer switch. The system is said to fail when n − k + 1 units have failed. The distribution of time to failure and time to repair of a unit are negative exponential. Using the regenerative point technique several reliability characteristics are obtained to carry out the cost-benefit analysis. 相似文献
9.
A comprehensive modeling framework involving mutually uncorrelated contribution from interface trap generation and hole trapping in pre-existing, process related gate insulator traps is used to study NBTI degradation in SiON and HKMG p-MOSFETs. The model can predict time evolution of degradation during DC and AC stress, time evolution of recovery after stress, impact of stress and recovery bias and temperature, and impact of several AC stress parameters such as pulse frequency, duty cycle, duration of last pulse cycle (half or full) and pulse low bias. The model can successfully explain experimental data measured using fast and ultra-fast methods in SiON and HKMG devices having different gate insulator processes. The trap generation and trapping sub components of the composite model have been verified by independent experiments. Data published by different groups are reconciled and explained. The model can successfully predict long time DC and AC stress data and has been used to determine device degradation at end of life as EOT is scaled for different HKMG devices. 相似文献
10.
Clustering is one of the essential operations in wireless sensor network (WSN) to ensure organized data aggregation followed by energy efficiency. However, obtaining optimal clustering performance is yet an unsolved problem in WSN. Review of existing approaches towards cluster optimization shows that effective balance between energy efficiency and topology control is still missing. Therefore, the proposed system presents a unique topology control mechanism using a novel concept of interstellar orientation toward optimizing the clustering performance in WSN. Adopting an analytical research methodology, the proposed system introduces two interstellar‐based topology control system, which targets the maximum saving of resource consumption of the cluster head. The simulated outcome of the study shows that the proposed topology control system offers significant energy conservation performance in comparison to the existing hierarchical clustering scheme in WSN. 相似文献