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11.
2008年6月,温家宝总理在省区市和中央部门主要负责同志会议上指出:今年以来,我国经济社会发展经受了最为严峻的重大挑战和考验。这也让我们更加关注企业生存和发展的国际国内环境。 相似文献
12.
中国橡胶工业协会力车胎分会4月15~16日在青岛市召开了第十五次会员大会,大会总结了第六届理事会工作,讨论并通过推荐第七届理事和总会理事名单、副理事长和总会常务理事名单,确认了分会理事长、秘书长。讨论通过了第七届理事会工作设想及安排。 相似文献
13.
我国工程机械现状及今后发展趋势 总被引:1,自引:0,他引:1
中国的工程机械行业建立于1961年。改革开放以后,由于国内对工程机械的需求量大,自1978年开始至20世纪末共引进近200项技术.发展了近500个新产品。使我国的工程机械迈上了一个新的台阶,当年引进的产品目前已成为我国工程机械的主导产品。 相似文献
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Oxide films were deposited on different substrates by laser molecular beam epitaxy. Reflection high-energy electron diffraction was performed to in situ investigate the change of growth mode and the lattice relaxation during the growth. An asymmetrical phenomenon was found in the two kinds of strain states, compressive stress and tensile stress of heterostructures with different lattice mismatch. In the case of BaTiO3/SrTiO3 (2.2%), 2D layer-by-layer growth mode without lattice relaxation can be maintained for a longer period for BTO films on STO with compressive stress, comparing to STO films on BTO with tensile stress. When MgO films were deposited on SrTiO3 with a large mismatch of 7.8%, compressive stress leads to rapid lattice relaxation with a very thin wet layer, and 3D strained island were observed. As a comparison, SrTiO3 films on MgO with tensile stress were configured. No RHEED patterns can be observed duo to a large tensile stress. 相似文献
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17.
On effective offloading services for resource-constrained mobile devices running heavier mobile internet applications 总被引:1,自引:0,他引:1
Kun Yang Shumao Ou Hsiao-Hwa Chen 《Communications Magazine, IEEE》2008,46(1):56-63
Rapid advances in wireless mobile network technologies and mobile handsets (MHs) facilitate ubiquitous infrastructure that can support a range of mobile services and applications in addition to conventional mobile Internet access. One recent trend is to effectively run desktop PC-oriented heavier applications on MHs. However, due to their miniature, portable size, MHs are resource-constrained and therefore, running these applications directly on an MH is not satisfactory given a user's expectations. To cope with this problem, this article proposes a novel offloading service that can seamlessly offload some of the tasks of a mobile application from an MH to nearby, resource-rich PCs (called surrogates). The system architecture and key components of the proposed offloading service are presented, prototyped, and evaluated. The results of experiments and simulations have demonstrated the effectiveness and efficiency of this offloading service for mobile applications. 相似文献
18.
Chun Yang Yin Sharifah Aishah Syed Abdul KadirYing Pei Lim Sharifah Nawirah Syed-AriffinZurinawati Zamzuri 《Fuel Processing Technology》2008
Ash derived from combustion of Malaysian oil palm biomass (empty fruit bunches consisting of fibers) was physically and chemically characterized in order to provide a comprehensive understanding of its specific properties in terms of toxicity, compositions and reusability. Principal analyses conducted include particle size distribution, scanning electron microscopy, elemental dispersive X-ray, elemental analysis, toxicity characteristic leaching procedure (TCLP) as well as thermogravimetric, X-ray diffractometry and Fourier-transform infrared analyses. TCLP result indicated that the oil palm ash (OPA) should not be classified as toxic wastes in terms of heavy metal leachability since leachable copper, cadmium, lead and nickel concentrations were detected below the stipulated leachability limits. It was determined that the OPA contained high amount of potassium as well as presence of silica which implied its suitability to be reused as crude fertilizer or cement replacement material. 相似文献
19.
We present a numerical study of the packing of uniform spheres under three-dimensional vibration using the discrete element method (DEM), focusing on the effects of vibration condition (amplitude and frequency) and inter-particle frictions (sliding and rolling frictions). The results are analysed in terms of packing density, coordination number (CN), radial distribution function (RDF) and pore structure. It is shown that increasing either the vibration amplitude or frequency causes packing density to increase initially to a maximum and then decrease. Both vibration frequency and amplitude should be considered to characterize the effect of vibration process on packing structure. The sliding and rolling frictions between particles can decrease packing density since they dissipate energy, although the effect of rolling friction is less significant. In line with the change of packing density, microstructural properties such as CN, RDF and pore distribution also change: a looser packing often corresponds to smaller CN, less peaked RDF and larger but more widely distributed pores. 相似文献
20.
Seyeong Choi Alouini M.-S. Qaraqe K.A. Hong-Chuan Yang 《Wireless Communications, IEEE Transactions on》2008,7(2):495-499
We propose and analyze new finger assignment techniques that are applicable for RAKE receivers in the soft handover (SHO) region. Specifically, extending the results for the case of two-base station (BS), we consider the multi-BS situation, attack the statistics of several correlated generalized selection combining (GSC) stages, and provide closed-form expressions for the statistics of the output signal-to-noise ratio (SNR). By investigating the tradeoff among the error performance, the average number of required path estimations/comparisons, and the SHO overhead, we show through numerical examples that the new schemes offer commensurate performance in comparison with more complicated GSC-based diversity systems while requiring a smaller estimation load and SHO overhead. 相似文献