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排序方式: 共有1016条查询结果,搜索用时 15 毫秒
1.
Yang Chao-Tung Chen Shuo-Tsung Liu Jung-Chun Chan Yu-Wei Chen Chien-Chih Verma Vinod Kumar 《The Journal of supercomputing》2019,75(8):4408-4429
The Journal of Supercomputing - In the last decade, cloud computing has brought enormous changes to people’s lives. Cloud computing gives a client-driven computational model. In this case,... 相似文献
2.
A Synthetic Transcriptional Activator of Genes Associated with the Retina in Human Dermal Fibroblasts 下载免费PDF全文
3.
At high temperatures in clean oxidizing environments, SiC forms a very protective SiO2 film, but, in environments containing low levels of gaseous alkali salt contaminants or where condensed salts may deposit on the surface, the resistance of the film is significantly reduced. Oxidation kinetics of SiC were measured by continuous thermogravimetric analysis in a controlled environment containing CO2 , H2 O, and O2 plus low levels of potassium-containing salts. Potassium was found to be incorporated into the SiO2 scale and to significantly change its transport properties and its morphology. The rate of scale formation was found to increase directly in proportion to K in the scale. A change in mechanism was observed when water vapor was added to the reacting gas stream. 相似文献
4.
The study focused on the in-situ synthesis of titanium (Ti)-titanium boride (TiB) composites with β phase in the matrix by reaction sintering of TiB2 with Ti and alloying element powders. The goal was to examine the nature of TiB whisker formation in three different kinds
of powder mixtures: (1) β-Ti alloy powders and TiB2; (2) α-Ti powder, a master alloy (Fe-Mo) powder containing the β-stabilizing elements, and TiB2; and (3) α-Ti powder, a β-stabilizing elemental powder (Mo or Nb), and TiB2. The effects of powder packing and the relative locations of powder particles on the morphological changes in TiB whisker
formation and their growth were studied at processing temperatures ranging from 1100°C to 1300°C. The morphology, size, and
distribution of whiskers were found to be influenced by the powder-packing conditions. A large particle-size ratio in bimodally
packed mixtures led to the formation of a TiB monolithic layer around β grains. With a relatively finer starting powder, smaller size ratio, and trimodal packing arrangement, the TiB whiskers were
found to be distributed more homogeneously in the matrix. The study also used the X-ray direct comparison method and the structure
factor for the β phase to determine the volume fraction of TiB phase from X-ray data. Tensile tests and fractographic investigations were
carried out on selected composites. The evolution of the composite microstructure, the influence of powder-packing variables,
and the morphology and growth of TiB whiskers and their effect on mechanical properties are discussed. 相似文献
5.
Low-power and high-speed discrete cosine transform (DCT) implementation of the images captured by the satellites presents a hardware design problem. The cost of the DCT implementation is dominated by the complexity of the multiplication of input data (image) with the DCT matrix. The techniques for minimising the complexity of multiplication by employing a differential pixel method are presented. In the proposed method 8times8 blocks of input image matrix are considered, the difference between the adjacent pixels is calculated and those differential pixels are used in DCT transformation. Synthesis results on 0.18 mum CMOS technology show that the proposed method gives an average of 13.2% reduction in power consumption and 10.9% improvement in speed over the conventional method. The proposed method can also be combined with the common subexpression elimination method for further reduction. 相似文献
6.
Microsystem Technologies - In this article, a rectangular solid-core photonic crystal fiber (PCF) is proposed as temperature sensor. The air-holes of the PCF have been filled with Ethyl alcohol... 相似文献
7.
Takatoshi Yamada Purayath Robert Vinod Doo-Sup Hwang Hiromichi Yoshikawa Shin-ichi Shikata Naoji Fujimori 《Diamond and Related Materials》2005,14(11-12):2047
This paper describes a self-aligned fabrication process for diamond gated field emitter array (FEA). Utilizing the non-conformal coverage sputtering conditions of silicon oxide, an interesting “sphere on cone” structure is formed on diamond nano tip array, which is the key point of gate hole opening process. This structure causes shadowing at certain regions of side-wall during Ti / Au gate metal deposition. Removal of “sphere” by wet etching leads to the successful fabrication of a single crystalline diamond gated FEA. Scanning electron microscope observations reveal the fabrication of a uniform emitter array with tip radius of curvature (20 nm) and gate hole (1.4 μm). We also confirmed that no noticeable physical damage exists on tip. In field emission characteristics of the fabricated single crystal diamond gated FEA, gate voltage control of field emission current is realized. 相似文献
8.
A simple and efficient new method for QRS detection in Electrocardiogram (ECG) is proposed in this paper. Initially data is preprocessed using two stage median filter for removing baseline drift. The second stage enhances the peaks of ECG wave components by using sixth power of signal. The next stage identifies the QRS complex by taking a variable window size. The detection sensitivity (Se) and positive predictivity (+P) of CSE (Common Standards for Quantitative Electrocardiography) measurement database, MIT/BIH (Massachusetts Institute of Technology/Beth Israel Hospital) Arrhythmia database, European ST-T database and QT database are Se 99.51 & +P 99.69%, Se 99.21 & +P 99.34%, Se 99.53 & +P 99.72% and Se 99.87 & +P 99.95% respectively. These four standard databases used to perform QRS detection considered 368 cases, tested 1,006,168 beats and achieved overall average sensitivity 99.52% and positive predictivity 99.69%. The MIT/BIH Noise Stress Test Database also tested by proposed method. 相似文献
9.
M. Sharan Chandran K. Padmanabhan D. K. Dipin Raj Yashasvi Chebiyyam 《Journal of Adhesion Science and Technology》2020,34(5):511-530
AbstractInterfacial adhesion of composite materials plays an important role in their mechanical properties and performance. In the present investigation, analysis of the interfacial properties of self-reinforced polyamide composites by using microbond multiple fibre pull-out test is emphasised. Microbond specimens prepared through thermal processing are tested for their interfacial properties by multiple fibre bundle pull-out tests and compared with that of traditional single fibre pull-out test specimens. Multiple fibre pull-out addresses the volume fraction as well as eliminates the possibility of fibre breakage before matrix shear. Higher scatter in the data in the samples is addressed in the present studies. FTIR and Fractographic studies are carried out for deep understanding of the post pull-out interfacial adhesion. 相似文献
10.
Multimedia Tools and Applications - In today’s Internet era, group communications in multimedia applications are becoming more and more popular. The issues of controlling illegal access to... 相似文献