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81.
Experimental thermal hydraulic research has been conducted at Oregon State University for the purpose of assessing the performance of a new reactor design concept, the multi-application small light water reactor (MASLWR). The MASLWR is a pressurized light water reactor design with a net output of 35 MWe that uses natural circulation in both normal and transient operation. Due to its small size, portability and modularity, the MASLWR design is well suited to help fill the potential need for grid appropriate reactor designs for smaller electricity grids as may be found in developing or remote regions. The purpose of the OSU MASLWR test facility is to assess the operation of the MASLWR under normal full operating pressure and full temperature conditions and to assess the passive safety systems under transient conditions. The data generated by the testing program will be used to assess computer code calculations and to provide a better understanding of the thermal-hydraulic phenomena in the design of the MASLWR NSSS. During this testing program, four tests were conducted at the OSU MASLWR test facility. These tests included one design basis accident and one beyond design basis accident. During the performance of these tests, plant operations to include start up, normal operation and shut down evolutions were demonstrated successfully.  相似文献   
82.
Brian Dipert 《电子设计技术》2005,12(11):72-72,74,76,78,80-81
顾客想要统一格式的蓝色激光存储器。但各竞争方无视这种需求,把不兼容的产品大量推向市场.进行一场高技术的赌博。  相似文献   
83.
We propose an image hashing paradigm using visually significant feature points. The feature points should be largely invariant under perceptually insignificant distortions. To satisfy this, we propose an iterative feature detector to extract significant geometry preserving feature points. We apply probabilistic quantization on the derived features to introduce randomness, which, in turn, reduces vulnerability to adversarial attacks. The proposed hash algorithm withstands standard benchmark (e.g., Stirmark) attacks, including compression, geometric distortions of scaling and small-angle rotation, and common signal-processing operations. Content changing (malicious) manipulations of image data are also accurately detected. Detailed statistical analysis in the form of receiver operating characteristic (ROC) curves is presented and reveals the success of the proposed scheme in achieving perceptual robustness while avoiding misclassification.  相似文献   
84.
男人在所有的社会中都拥有更多的机会获取到更优越的交通工具,他们更经常使用家庭小汽车或是利用可支配收入使用公共交通替代步行。不必提较差的工作与教育机会,机动化的缺乏就往往在给妇女长期带来不利经济地位的问题上扮演着一个被忽视的、但却十分重要的作用。  相似文献   
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Bifurcated nozzles are used in continuous casting of molten steel, where they influence the quality of the cast steel slabs. The present study performs two-dimensional (2-D) and three-dimensional (3-D) simulations of steady turbulent(K- ε) flow in bifurcated nozzles, using a finite-element (FIDAP) model, which has been verified previously with water model experiments. The effects of nozzle design and casting process operating variables on the jet characteristics exiting the nozzle are investigated. The nozzle design parameters studied include the shape, angle, height, width, and thickness of the ports and the bottom geometry. The process operating practices include inlet velocity profile and angle as well as port curvature caused by erosion or inclusion buildup. Results show that the jet angle is controlled mainly by the port angle but is steeper with larger port area and thinner walls. The degree of swirl is increased by larger or rounder ports. The effective port area, where there is no recirculation, is increased by smaller or curved ports. Flow asymmetry is more severe with skewed or angled inlet conditions or unequal port sizes. Turbulence levels in the jet are higher with higher casting speed and smaller ports. Formerly Research Assistant, Department of Mechanical and Industrial Engineering. Formerly Research Assistant in the same department.  相似文献   
88.
In this article, we report studies of two new forms of highly active supported catalysts. First, those derived from supported carbonylate clusters—nanocatalysts and second, those produced from the heterogenization of known chiral homogeneous systems. The utilization of established cluster compounds of precisely known composition and structure have proved invaluable in the preparation of mixed metal nanoparticles of well-defined composition. The attachment of these nanoparticles to the inner walls of mesoporous silica has led to the development of highly active and effective catalysts for a series of hydrogenation reactions, emphasizing the enhanced reactivity of these metal systems as a consequence of their size and of the low coordination numbers of the metal atoms involved. These attributes combined with the relative ease of characterization of both the active sites and their location has led to a detailed examination of the role of these nanosystems in a new approach to clean technology. In an alternative strategy, the use of heterogenized homogeneous chiral catalysts based on the ferrocenyl moiety and diamino ligands and linked to the inner surface of mesoporous materials either by a direct chemical bond or by an ionic interaction has also been explored. These catalysts have been shown to be highly effective in the enantioselective synthesis of organic compounds. Significantly, we have found that the mesopore (usually MCM-41) imposes spatial restrictions arising from the concavity of the inner surface and leads to greatly enhanced enantioselective (ee) performance.  相似文献   
89.
Chromatic luminance (i.e., luminance of a monochromatic color) is the source of all luminance, since achromatic luminance arises only from mixing colors and their chromatic luminances. The ratio of chromatic luminance to total luminance (i.e., chromatic plus achromatic luminance) is known as colorimetric purity, and its measurement has long been problematic for nonspectral hues. Colorimetric purity (pc) is a luminance metric in contrast to excitation purity, which is a chromaticity‐diagram metric approximating saturation. The CIE definition of pc contains a fallacy. CIE defines maximum (1.0) pc for spectral stimuli as monochromatic (i.e., optimal) stimuli, and as the line between spectrum ends for nonspectrals. However, this line has <0.003 lm/W according to CIE colorimetric data and is therefore effectively invisible. It only represents the limit of theoretically attainable colors, and is of no practical use in color reproduction or color appearance. Required is a locus giving optimal rather than invisible nonspectral stimuli. The problem is partly semantic. CIE wisely adopted the term colorimetric purity, rather than the original spectral luminance purity, to permit an equivalent metric for spectrals and nonspectrals, but the parameter of equivalence was never clear. Since 1 pc denotes optimal aperture‐color stimuli for spectrals, arguably 1 pc should denote optimal stimuli consistently for all stimuli. The problem reduces to calculating optimal aperture‐color stimuli (“optimal” in energy efficiency in color‐matching) for nonspectrals, shown to comprise 442 + 613 nm in all CIE illuminants. This remedy merely requires redefinition of 1 pc for nonspectrals as the line 442–613 nm, and gives meaningful pc values over the hue cycle allowing new research of chromatic luminance relations with color appearance. © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 469–476, 2007  相似文献   
90.
Contends that tests in repeated-measures designs based on MANOVA are free of sphericity assumptions, and with modern computing software, MANOVA is straightforward to use, even for complex designs and nontraditional hypotheses. A general strategy for implementing MANOVA within statistical computing packages is presented. Regular (preplanned) tests and simultaneous (post hoc) tests are illustrated for a variety of designs and hypotheses. Optimal contrasts for unbalanced repeated measures designs are appended. (33 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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