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81.
Unique, floating-point length-4 vector instructions prove more effective than conventional SIMD architecture for 3D graphics processing  相似文献   
82.
Buckling was observed under hydraulic pressure in a multi-mode plastic-coated optical fibre with a buffer layer. The optical loss increase by buckling was examined. It was found that the occurrence of buckling can be estimated from the relationship between compressibility and Young's modulus of the coating materials.  相似文献   
83.
84.
Chow and Kaneko proposed a method of variable thresholding in which an image is divided into windows; thresholds are selected for those windows that have bimodal histograms; and these thresholds are interpolated to define a variable threshold for the entire image. This method was applied to several TV images of machine parts; the results obtained appeared to be considerably better than the results of thresholding at a fixed level. An extension of the method was defined that allowed histograms to be either bimodal or trimodal; this yielded some further improvement in the results, but was also more sensitive to shadows. Finally, an adaptive quantization scheme, based on histogram peak sharpening, was applied to two of the images; the results do not seem to be as good as those obtained using variable thresholding.  相似文献   
85.
A failure model with degradation and catastrophic modes is briefly discussed and some general equations are shown.  相似文献   
86.
The permeability of poly-L -methionine (PLM) membrane and its oxidized form to water vapor was studied. Permeability coefficients of the PLM membrane were large, of the order of 10?7 cm3 (S.T.P.)·cm/cm2·sec·cm Hg. The sorption and permeation behavior of the PLM membrane was hydrophobic. The oxidized membrane was prepared by treating one or both sides of the PLM membrane with an aqueous solution of hydrogen peroxide. The membrane oxidized from one side is probably not layered but has a gradient of composition from one surface to the other. The amounts of water sorbed by the modified membrane increased with increase in oxidation time. The permeability coefficients of water vapor through the modified membrane were of the order of 10?6 cm3 (S.T.P.)·cm/cm2·sec·cm Hg.  相似文献   
87.
A system with a special operating unit is considered. We determine when the spare unit should be delivered and replaced for the original one, where the delivery time is considered. Four models are introduced and the delivery policy for each model is found which maximizes the s-expected net earning rate (with no discount) or the total s-expected net earnings (with discount).  相似文献   
88.
An experimental study has been carried out on the characteristics of binary adsorption isotherms of water and volatile flavor for typical materials used in a box of a tobacco product or cigarettes. Ethyl acetate chosen as a model for water-soluble volatile flavor. Binary adsorption isotherms for the tobacco, papers, filters, and activated carbons were measured with a flow-type multi-component adsorption system under the canstant conditions of temperature a t 303 K and vapor pressure of water a t 2.5 kPain the vapor pressure range of ethyl acetate from 0 to 4.2 kPa. A linear equation was applied to express the binary adsorption isotherms for the tobacco, papers and filters, while a Dubinin-Astakhov equation was applied for the activated carbons. The binary adsorption was characterized into three groups, depending on the selectivity as well as the mechanism of adsorption; i.e.(l) for tobacco and papers, water was adsorbed much greater rather than ethyl acetate, (2) for filters, ethyl acetate was adsorbed on the surface as great as water, (3) for activated carbons, ethyl acetate was adsorbed much greater onto their micropores rather than water. The results showed that ethyl  相似文献   
89.
The Gmicro/500, which features a RISC-like dual-pipeline structure for high-speed execution of basic instructions and represents a significant advance for the TRON architecture, is presented. Upwardly-object-compatible with earlier members of the Gmicro series, this microprocessor uses resident dedicated branch buffers to greatly enhance branch instruction execution speed. Its microprograms simultaneously use dual execution blocks to execute high-level language instructions effectively. Fabricated with a 0.6-μm CMOS technology on a 10.9-mm×16-mm die, the chip operates at 50/66 MHz and achieves a processing rate of 100/132 MIPS  相似文献   
90.
The authors have conducted a laboratory-scale gallery fire test on eight different samples of electric cable in a horizontal airflow. The number of speciments and the distances between them on the trestle were varied for each test. As a result, it was found that both ignitability and flame-propagation properties depended on the distance between the specimens as well as on their number. Such flammability properties obtained for each cable sample were also found to be considerably consistent with the critical oxygen index. In addition, it is proposed that the flammability should be classified largely into five categories in this laboratory-scale gallery fire test for fire-retardance evaluation of solid combustible materials such as electric cables.  相似文献   
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