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61.
A mode based on an additive mechanism of heat transfer is proposed for forced convection subcooled boiling of binary mixtures. The contributing modes of heat transfer are: (i) the heat transferred as latent heat by the rising bubbles, (ii) the heat transferred as the heat contained in the superheated thermal layer that is removed from the surface in the wake of the rising bubbles and (iii) the single phase forced convection heat transfer from the heating surface not influenced by the bubbles. Experimental data from the literature on binary systems show good agreement with the model, validating the postulated mechanism. 相似文献
62.
The Journal of Supercomputing - Building sentiment analysis resources is a fundamental step before developing any sentiment analysis model. Sentiment lexicons are one of these critical resources.... 相似文献
63.
A technique has been developed to obtain optimum difference mode excitations for monopulse arrays. In addition, a direct interpolation scheme has been devised for situations where near-optimum results would suffice. A parameter designated asu_{0} is identified with every optimum difference pattern. The choice of this parameteru_{0} determines the sidelobe level of the optimum pattern. The problem of obtaining the optimum excitations has been shown to be reducible to one of finding out the best approximation that minimizes the maximum deviation (minimax) from the real line (u = betad cos varp axis), over a range determined byu_{0} . This latter problem has been solved using a modified Remez exchange algorithm. An extensive set of design curves has also been presented. 相似文献
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Sebastian Riedle John W. Wills Michelle Miniter Don E. Otter Harjinder Singh Andy P. Brown Stuart Micklethwaite Paul Rees Ravin Jugdaohsingh Nicole C. Roy Rachel E. Hewitt Jonathan J. Powell 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(21)
Human exposure to persistent, nonbiological nanoparticles and microparticles via the oral route is continuous and large scale (1012–1013 particles per day per adult in Europe). Whether this matters or not is unknown but confirmed health risks with airborne particle exposure warns against complacency. Murine models of oral exposure will help to identify risk but, to date, lack validation or relevance to humans. This work addresses that gap. It reports i) on a murine diet, modified with differing concentrations of the common dietary particle, food grade titanium dioxide (fgTiO2), an additive of polydisperse form that contains micro‐ and nano‐particles, ii) that these diets deliver particles to basal cells of intestinal lymphoid follicles, exactly as is reported as a “normal occurrence” in humans, iii) that confocal reflectance microscopy is the method of analytical choice to determine this, and iv) that food intake, weight gain, and Peyer's patch immune cell profiles, up to 18 weeks of feeding, do not differ between fgTiO2‐fed groups or controls. These findings afford a human‐relevant and validated oral dosing protocol for fgTiO2 risk assessment as well as provide a generalized platform for application to oral exposure studies with nano‐ and micro‐particles. 相似文献
67.
G. Balakrishnan P. Kuppusami S. Murugesan Chanchal Ghosh Divakar Ramachandran E. Mohandas D. Sastikumar 《Transactions of the Indian Institute of Metals》2011,64(3):297-299
Multilayers of CeO2/ZrO2 thin films were deposited on Si (100) substrates using pulsed laser deposition at an optimized oxygen partial pressure of
3×10−2 mbar and at room temperature. The CeO2 layer thickness was 10 nm, while the ZrO2 layer thickness was varied as 10, 20 and 30 nm. CeO2 and ZrO2 layers were deposited alternately to obtain 25 bilayers. High temperature x-ray diffraction (HTXRD) results showed that the
multilayer films had cubic ceria and tetragonal ZrO2. Thermal expansion coefficients were calculated for CeO2 and t-ZrO2 and found to increase with the decrease of ZrO2 layer thickness. The cross sectional transmission electron microscopy (XTEM) of CeO2/ZrO2 multilayer also indicated that ceria was found to be in cubic phase while zirconia contained predominantly tetragonal phase
along with cubic phase in thermally annealed specimen. 相似文献
68.
Pose-aware devices, in concert with functional geometric models describing architectural spaces, enable a new class of indoor applications, including resource location, route finding, direct population and annotation of world models, and direct information overlay. The article describes these applications along with the device infrastructure and algorithms required to support them. We demonstrate a few prototype devices and applications now underway and point to future directions in which these techniques might evolve. 相似文献
69.
Balakrishnan Meera Puliafito Antonio Trivedi Kishor Viniotis Yannis 《Telecommunication Systems》1997,7(1-3):105-123
The B‐ISDN will carry a variety of traffic types: the Variable Bit Rate traffic (VBR), of which compressed video is an example,
Continuous Bit Rate traffic (CBR), of which telemetry is an example, Data traffic, and Available Bit Rate traffic (ABR) that
represents aggregate data traffic with very limited guarantees on quality. Of these, VBR and CBR have timing constraints and
need synchronous bandwidth; data traffic is relatively delay insensitive. In this paper, we consider the VBR, Data and ABR
traffic types and obtain the cumulative distribution function (cdf) of the queueing delay experienced by a burst of ABR traffic
in the output buffer of an ATM switch. The cdf is used to trade off buffer loss probabilities against deadline violation probabilities
through adjusting the buffer size and (delay) deadline values. Large buffers result in low losses but queueing delays can
become excessive and cause a high level of deadline violations. Both losses and violations are detrimental and an operating
point must be chosen to achieve a balance. In this paper we study the nature of the trade off. We develop a stochastic Petri
net model assuming periodic burst arrivals for VBR and Poisson arrival processes for the Data and ABR traffic types at the
burst level, and solve the model analytically (numerically) using a decomposition approach. This decomposition, along with
the inherent decomposability of the tagged customer approach for obtaining the cdf opens up a possibility of carrying out
fast computations using a parallel machine for selecting the operating point each time that a call is admitted.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
70.
Balakrishnan J. D.; MacDonald Justin A.; Kohen Hamid S. 《Canadian Metallurgical Quarterly》2003,57(3):238
Green's well-known area theorem establishes an equivalence between the area under the yes-no ROC curve and the percent correct of an unbiased observer in a two-alternative forced-choice (2AFC) task with equivalent stimuli. In this article, we show that this conversion from yes-no detection data to hypothetical performance in a 2AFC task is unnecessary: The same yes-no detection data that are used to compute the area statistic can always be used to compute the percent correct of an unbiased observer in the yes-no detection task itself. We also show that the ROC curve may not be the ideal graphical device for many investigators. A more natural representation of the difficulty of a discrimination task is obtained by plotting the distribution of the posterior betting odds under equal base rates, which can be estimated from their distributions under unequal base rates. Finally, unlike the area measure and other traditional detection theory statistics, both the yes-no percent correct measure and the odds distributions generalize in an obvious and direct way to classification paradigms with more than two responses (e.g., identification). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献