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61.
Silicon - This paper examines a Junctionless quadruple gate (JLQG) MOSFET for analog and linearity distortion performance by numerically calculating transconductance and its higher order... 相似文献
62.
P. S. Niranjan Ratna Shukla Santosh K. Upadhyay 《Journal of surfactants and detergents》2012,15(1):53-57
The aggregation behaviour of two cationic surfactants, viz. cetyl trimethyl ammonium bromide (CTAB) and N-cetyl pyridinium
chloride (CPC), in different concentrations of water-soluble polyacrylamide has been studied in alkaline medium by electrical
conductivity and surface tension measurements. A decrease in the critical micelle concentration (CMC) of the surfactant with
an increase in polymer content in the mixture was observed. The thermodynamic and surface parameters have been determined
and discussed. The results indicate that micellisation becomes more favourable at higher polymer content. 相似文献
63.
In present communication, we propose a modified resource allocation strategy, namely, hybrid connection algorithm, for achieving efficient restoration in WDM optical networks. The main theme of the algorithm is that, while attempting connection establishment, a wavelength is reserved in advance for providing resources for backup lightpaths. The analysis and the comparison of the proposed strategy with other existing strategies has been undertaken using metrics such as, restoration efficiency, number of wavelength links used by primary and backup lightpaths, and the percent link utilization. The proposed strategy provides 100% restoration efficiency and much better performance than the existing techniques. 相似文献
64.
Santosh K. Nanda Ariel L. Rivas William M. Trochim J. David Deshler 《Scientometrics》2000,48(1):45-64
The emphasis of validity as a publication content was investigated in dissertations and journal articles. The time of first publication, longitudinal publication profile, ratio of articles to dissertations, and time lag between dissertations and articles emphasizing validity were compared within and among various fields. A three-decade gap separated the first field adopting validity-related contents in its dissertations from the latest fields that did so. The longitudinal data suggested three groups of fields (Agricultural Sciences, Applied Sciences and Social Sciences) which showed consistent differences among groups and consistent similarities within groups in their emphasis on validity-related content. Adoption of validity-related content in dissertations always preceded adoption of validity-related content in journal articles. On average, less than 4% of journal articles included validity-related content across fields. These findings support the hypothesis that validity has been introduced and disseminated within fields following patterns predicted by diffusion of innovations theory. It is argued that this pattern is inconsistent with an efficient and interdisciplinary utilization of available knowledge. Policy recommendations are made for developing strategic communication and education programs for academicians and journal reviewers. 相似文献
65.
Yonghong Huang Deniz Erdogmus Misha Pavel Santosh Mathan Kenneth E. Hild 《Neurocomputing》2011,74(12-13):2041-2051
We report the design and performance of a brain computer interface for single-trial detection of viewed images based on human dynamic brain response signatures in 32-channel electroencephalography (EEG) acquired during a rapid serial visual presentation. The system explores the feasibility of speeding up image analysis by tapping into split-second perceptual judgments of humans. We present an incremental learning system with less memory storage and computational cost for single-trial event-related potential (ERP) detection, which is trained using cross-session data. We demonstrate the efficacy of the method on the task of target image detection. We apply linear and nonlinear support vector machines (SVMs) and a linear logistic classifier (LLC) for single-trial ERP detection using data collected from image analysts and naive subjects. For our data the detection performance of the nonlinear SVM is better than the linear SVM and the LLC. We also show that our ERP-based target detection system is five-fold faster than the traditional image viewing paradigm. 相似文献
66.
Rahul B. Kasat Ajay K. Ray Santosh K. Gupta 《Materials and Manufacturing Processes》2003,18(3):523-532
In the last several years, genetic algorithm (GA) has gained wide acceptance as a robust optimization algorithm in almost all areas of science and engineering. Polymer science and engineering is no exception. Researchers in this field have devoted considerable attention to the optimization of polymer productionusing objective functions and constraints that lead to products having desired material properties. Multiple-objective functions have been optimized simultaneously. An example is the minimization of the reaction time in a reactor (lower costs) while simultaneously minimizing the concentration of side products (that affect the properties of the product adversely). Several end-point constraints (equality or inequality) may also be present, as, e.g., obtaining polymer of a desired molecular weight. Again, this requirement stems from producing polymer having desired strength. Solving such problems usually result in Pareto sets. A variety of adaptations of GA have been developed to obtain optimal solutions for such complex problems. These adaptations can be used to advantage in other fields too. The applications of GA in areas of polymer science and engineering other than polymerization systems are few and far between, but this field is now maturing, and it is hoped that the future will see several newer applications. 相似文献
67.
M. Vanathi Geeta Behera Sujith Vengayil Anita Panda S. Khokhar 《Contact lens & anterior eye》2008,31(3):164-166
PURPOSE: To report a case of acute hydrops in pellucid marginal corneal degeneration (PMCD) documented with anterior segment optical segment tomography and successfully treated with sulphur hexafluoride (SF6) intracameral injection. METHODS: A 47-year-old female patient presented with spontaneous onset of pain, redness and decreased vision in her left eye. Clinical evaluation revealed bilateral PMCD with evidence of acute hydrops in the left eye. Anterior segment Slit lamp Adapted Optical Coherence Tomography (SL-OCT) examination revealed intrastromal clefts with Descemet's membrane detachment in the left eye. She was managed with descemetopexy with 0.2ml injection of iso-expansile SF6 (18%) intracameral. RESULTS: The patient showed excellent early resolution of the stromal edema with reattachment of the Descemet's membrane. CONCLUSION: Prompt intervention in acute hydrops in PMCD cases helps in achieving early good visual results and prevents potentially serious complications such as perforation. Newer imaging modalities like SL-OCT helps in better visualisation and also in monitoring the response to treatment. 相似文献
68.
Hambrusch S.E. Khokhar A.A. 《Parallel and Distributed Systems, IEEE Transactions on》1998,9(8):758-768
In s-to-p broadcasting, s processors in a processor machine contain a message to be broadcast to all the processors, 1⩽s⩽p. We present a number of different broadcasting algorithms that handle all ranges of s. We show how the performance of each algorithm is influenced by the distribution of the s source processors and by the relationships between the distribution and the characteristics of the interconnection network. For the Intel Paragon we show that for each algorithm and machine dimension there exist ideal distributions and distributions on which the performance degrades. For the Cray T3D we also demonstrate dependencies between distributions and machine sizes. To reduce the dependence of the performance on the distribution of sources, we propose a repositioning approach. In this approach, the initial distribution is turned into an ideal distribution of the target broadcasting algorithm. We report experimental results for the Intel Paragon and Cray T3D and discuss scalability and performance 相似文献
69.
Sjofn Sigurgisladottir Santosh P. Lall Christopher C. Parrish Robert G. Ackman 《Lipids》1992,27(6):418-424
Salmonid fish require long-chain n−3 fatty acids in their diet. The digestibility of different chemical forms of fish oil
fatty acids, fed as triacylglycerols, free fatty acids or ethyl esters, was examined in 300 g farmed Atlantic salmon (Salmo salar) using cholestane as an indicator of fat absorptionin lieu of the chromium oxide (Cr2O3) which is commonly used as a marker in digestibility studies. It was established that the two digestibility markers gave
similar results. Conveniently, cholestane does not require a separate analysis if fatty acids are to be determined by appropriate
gas-liquid chromatography. The long-chain polyunsaturated fatty acids were particularly well absorbed, the apparent digestibility
being 90–98% when feeding triacylglycerols or free fatty acids. However, the digestibility of monounsaturated fatty acids
(75–94%) was lower, and lower still for saturated fatty acids (50–80%). Ethyl esters of fatty acids were significantly less
well absorbed (P<0.05) than were the corresponding fatty acids in free acid or triacylglycerol form. Irrespective of dietary fat type, only
free fatty acids were identified in feces, indicating total hydrolysis of triacylglycerols and ethyl esters.
Presented in part at the World Aquaculture Society meeting, June 10–14, 1990, Halifax, Canada. 相似文献
70.
The recently developed mathematical technique for studying the parametric sensitivity of reactors is extended to include chain polymerization systems exhibiting the gel and glass effects, as well as physical property variations. The sensitivities of the two temperature maxima with respect to various parameters are computed. It is found that, for a sample system, poly(methyl methacrylate), all the sensitivities of the gel effect induced temperature peak attain their maxima at the same conditions—this leads to a generalized temperature sensitivity constraint applicable to reactor design or operation. This sensitivity boundary is associated with high conversions and high molecular weights. The analysis shows that the dimensionless propagation activation energy, ?p, and the dimensionless initiation activation energy, ?d, are the two most important parameters governing the system performance. Sensitivities of the gel effect-induced number average chain length peak with respect to various parameters are also obtained. Again, all of these chain length sensitivities show maxima at the same condition, leading to the concept of a generalized chain length sensitivity criterion of constraint. Most importantly, the temperature and chain length sensitivity boundaries are virtually identical. 相似文献