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91.
This paper deals with the problem of average life estimation when the life times follow negative exponential distribution. A minimum mean square error estimator belonging to the class of linear combination of complete sufficient statistics has been obtained. The estimator thus obtained requires knowledge of coefficient of variation. The effect of using a guessed value of coefficient of variation on the estimator has also been studied. 相似文献
92.
E. Aparna K. M. Lokanatha Rai M. Sureshbabu R. L. Jagadish S. L. Gaonkar K. Byrappa 《Journal of Materials Science》2006,41(5):1391-1393
A simple, rapid, high-yielding and environmentally benign method for the conversion of esters and amides to the corresponding
thio compounds was carried out using thiourea as thionating agent under solvothermal reaction. All the compounds isolated
in good yields were characterized both by spectral analysis and comparing them with the authentic samples synthesized using
the literature method. 相似文献
93.
Hyung Rai Oh Hwangjun Song 《Multimedia, IEEE Transactions on》2007,9(7):1535-1542
This paper presents metafile-based scalable caching and dynamic replacing algorithms for multiple videos over quality-of-service networks. A metafile for each video includes the cached-frame sequence, which is made by scalable caching algorithm minimizing client's buffer size and channel bandwidth under the general video traffic condition. Based on the metafiles, we propose a caching algorithm for multiple videos to effectively reduce both the buffer size and the required bandwidth and replacing algorithm to dynamically update the cached frames when user access pattern changes. Finally, experimental results are provided to compare the proposed algorithms with various existing caching and replacing algorithms. 相似文献
94.
Despite substantial discussion of the Internet's impact on individual activities, there is an absence of a theoretically grounded measure of Internet usage for the provisioning of information required by decision-makers. Our research addresses this void in the literature. We conceptualize Internet Usage for Information Provisioning (IUIP) as the degree to which the Internet is used to meet information requirements of individual decision-makers engaged in diagnostic decision-making tasks. Drawing on the information processing theoretical framework, three dimensions (usage for breadth of content, usage for depth of content, and usage for interaction dynamism) of IUIP are identified. The construct was validated through a two-phase empirical study conducted in the physician clinical decision-making context. The first phase involved interviewing physicians to establish face validity of the dimensions and to generate multi-item measures for each dimension. The second phase consisted of surveying physicians to evaluate measurement properties and nomological validity. Principal components analysis, confirmatory factor analysis, and partial least squares analysis were the primary statistical techniques used to analyze the data and evaluate construct validity. Our results suggest that decision-makers operating in uncertain and equivocal decision contexts use the Internet to a greater degree for their content needs and selective attention requirements. Our results also suggest that a fit between the user's information processing requirements and technology, and selected social norms, lead to higher levels of IUIP. Implications for practice and future research are discussed. 相似文献
95.
MA Hoffman E Valderrama A Fuchs M Friedman K Rai 《Canadian Metallurgical Quarterly》1995,75(5):1100-1103
BACKGROUND: Leukemic meningitis is rare in B-chronic lymphocytic leukemia (CLL) and B-prolymphocytic leukemia (PLL); a MEDLINE search for reports published 1960 and after disclosed only nine prior reports. A patient with stable Rai Stage II CLL/PL developed mental status changes. Lumbar puncture revealed a lymphocytic pleocytosis with prolymphocytes containing intracytoplasmic inclusions. METHODS: The patient's cerebrospinal fluid lymphocyte population was analyzed by immunophenotyping and electron microscopy. RESULTS: The studies revealed a clonal population of B prolymphocytes, with typical immunophenotypic and ultrastructural characteristics. The patient was treated with intrathecal chemotherapy with eventual resolution of the cerebrospinal fluid pleocytosis and return to his normal neurologic status. Prior studies also have revealed the efficacy of intrathecal chemotherapy. CONCLUSION: Leukemic meningitis in CLL or PLL is responsive to treatment with intrathecal chemotherapy. 相似文献
96.
A periodic analysis of a double basin solar still is presented in this paper. In this still waste hot water is fed into the lower basin at a constant rate such as is available from power stations or other industries. The effect of various parameters on the distillate output of the still is also investigated. 相似文献
97.
Ethylene glycol retention method, standardised by Dyal and Hendricks for clays and soils, has been used for determining specific surface areas of a large variety of adsorbent carbons differing widely in the extent as well as chemical nature of their surfaces. The proposed method yields values comparable with those obtained by the gaseous adsorption methods, irrespective of the oxygen contents of the carbons. A small amount of oxygen, probably within 0.2%, is essential to bring about proper wetting of the carbon by glycol. 相似文献
98.
Antibodies against Japanese encephalitis virus (JEV) were examined in 356 serum samples from individuals visiting Tribhuvan University Teaching Hospital using neutralization test. A total of 13.2% (47/356) seropositivity was observed. Antibody positivity against both Nakayama-NIH and Beijing-1 strains was seen in 7.9% subjects. Infection by Nakayama-NIH strain alone was seen to be 4.2% while 1.1% of study populations were found to be infected only by Beijing-1 strain. High antibody titer was observed in the 20-40 years age-group and did not increase with age. Seropositivity was more common in zone-A (Tarai) area compared to zone-B (Hills) and zone-C (Mountains). Spectrum of antigenicity of JEV in zone-A as shown by neutralization test was identical to Indian isolates (strains). Difference in seropositivity was observed against Nakayama-NIH and Beijing-1 strain in zone-B and C indicating recent spread of JEV in these areas. 相似文献
99.
Flat test specimens of a 10-micron grain size Al-33 pct Cu alloy were deformed in air over a range of strains at 450 °C (723
K) and at 10-5 strain per second, and examined by SEM. Direct observations and measurements were also made in a SEM during superplastic
deformation of a 5-micron Pb-Sn eutectic alloy at room temperature at a strain rate of about 10-5 s-1. Extensive grain boundary sliding was noted. Microcreep curves were obtained between initially adjacent grains and showed
that deformation is cyclical in nature and varies by several orders of magnitude locally from point to point. Many surface
grains are observed to change neighbors many times, to undergo some rotation and tilt, to show little change in size or shape,
and yet to avoid intergranular cracking. Superplastic deformation is a highly heterogeneous process, not unlike that observed
in the creep of conventional types of alloys at elevated temperatures, but differing in the extent of plastic deformation
free of intergranular cracking, combined with extensive recovery in the form of boundary migration.
Formerly a Graduate Student in the Department of Materials Science and Engineering at Massachusetts Institute of Engineering,
then Research Manager of SAIL in Ranchi, India 相似文献
100.