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81.
Knowledge and Information Systems - The standard machine learning tasks often assume that the training (source domain) and test (target domain) data follow the same distribution and feature space....  相似文献   
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Multimedia Tools and Applications - A scene-level two-pass video rate controller for high efficiency video coding (HEVC) standard is proposed in this paper. The proposed rate controller is suitable...  相似文献   
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In this work, effect of oxygen diffusion on curing of materials which are sensitive to ultra violet light (UV) in fabrication of microchannels using micromolds with oxygen permeability is investigated. The effects of physical boundary conditions of mold on microfabrication of polymeric arrays of high aspect-ratio microchannels in presence of oxygen inhibition and under variable UV intensity and dose are studied analytically and experimentally. Polydimethylsiloxane (PDMS) as the oxygen-permeable material and polyurethane methacrylate (PUMA) as the UV-curable substrate are selected for experiments. It is shown that for a wide range of exposure intensity and dose, a thin layer of PUMA resin with thickness of a few micrometers in contact with the mold remains uncured and inhibited by high concentration of oxygen molecules while the overall curing rate is reduced by about tenfold for PDMS compared to impermeable silicon mold. The direct impact of presence of high concentration of oxygen in both of mold and resin during UV curing and due to insufficient exposure dose and intensity is a considerable alteration in geometries of manufactured microstructures. The obtained results are crucial for method of use of micromolding and evaluation of fidelity of the replicated microstructures with the proposed design in terms of verticality of the walls and details of the transferring patterns that are important to microfluidic applications.

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Multimedia Tools and Applications - With the broad development and evolution of digital data exchange, security has become an important issue in data storage and transmission since digital data can...  相似文献   
88.
The influence of test temperature on the mechanical and fracture properties of a 20 vol% alumina particulate-reinforced 6061-aluminium matrix composite, in the peak-aged condition, was investigated in the temperature range 25–180 °C. Strength and stiffness were found to decrease but elongation to failure increased with increasing test temperature. However, the fracture toughness was relatively constant over this temperature range. The failure mechanism, the reaction zone around reinforcing particles, the number of debonded particles and void sizes were all significantly influenced by temperature. The role of the matrix/particle interface in the fracture process was also investigated.On leave at the Department of Mechanical Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.  相似文献   
89.
Polyaniline-supported acid salts such as polyaniline-hydrochloride, polyaniline-sulfate and polyaniline-nitrate were prepared by oxidation of aniline using ammonium persulfate as oxidizing agents. Polyaniline salts were used as catalyst for the preparation of β-acetamido ketones. Polyaniline-sulfate salt was found to be the best catalyst for the preparation of β-acetamido ketones. Present methodology offers several advantages, such as cheaper process, easy synthesis of stable catalyst, simple work-up procedure, and excellent activity with less amount of catalyst and in addition, the catalyst can be easily recovered after completion of the reaction and reusable without affecting its activity.  相似文献   
90.
On the capacity of the vector MAC with feedback   总被引:1,自引:0,他引:1  
In this correspondence, we determine the feedback capacity region of a two user Gaussian multiple-access channel (MAC) with multiple antennas at the base station and a single antenna at each user. The vector MAC with a single antenna at the base station and multiple antennas at each user is shown to be equivalent to a scalar MAC. We also determine the capacity enhancement due to feedback at high signal-to-noise ratio (SNR) for the scalar and vector MAC for any number of users. Extensions of the high SNR results to the vector broadcast channel are also provided.  相似文献   
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