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本文在分析局域网服务器信息缓冲区、数据包接受和发送缓冲区的相互关系基础上提出一种新的局域网服务器缓冲区设计方法─—广义随机Petri网方法,并给出了局域网服务器信息缓冲区的广义随机Petri网模型。该设计方法理论完备、严谨实用,且不再局限于追求某一边界值(上限或下限),并且避免了排队理论处理多级服务的繁琐公式。最后本文用一例题说明了这种方法的应用。  相似文献   
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The renewal of the urban waterfronts has become a major focus of attention for politicians and decision makers in the city’s management programs. The recognition of the patterns that define the waterfronts’ identity is essential to select new strategies of intervention for the environmental recovery. In order to create adequate environments for everyday life within a sustainable development, new links between human senses, human perception and design need to be created. Within this wide approach, the landscape and the soundscape play a significant role and can become a key driving force in the implementation of the changes. New techniques have to be tested to identify the sonic and visual parameters capable to explain the specificity of a waterfront. With this purpose, an artificial neural network (ANN) was developed, and the relative importance of the input variables was evaluated. The collected database was also analysed by multiple linear regression (MLR) to compare the outcomes of both models. The urban waterfront of Naples (Italy) was chosen as case study. The results obtained show that the performance of the neural network is better than the one of the linear regression (rANN = 0.949, rMLR = 0.639). The interpretation of the relative importance method is also quite satisfactory in the ANN.  相似文献   
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介绍了将0.9μm设计流程中的版图数据库缩到到0.6μm的过程,然后列出了使用0.6μm单元库所应作的流程的修改,主要包括布线和最终版图处理的过程,最后简单介绍了单元性能库的提升。  相似文献   
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The Raman spectra of 18O-thiosulfate ion (S1O−23) in H118O solution and the IR spectrum of 18O-sodium thiosulfate in the solid have been obtained. Normal Coordinate calculations fitting all the fundamental wavenumbers of both 16O and 18O isotopomers have been carried out transferring the GVFF of the sulfate ion as the starting point and employing a symmetry force field for the least-squares adjustment procedure. A comparison of the results is made with the known force fields for several sulfur compounds.  相似文献   
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胡静珍  唐长文  闵昊 《微电子学》2002,32(4):261-264
介绍了基于标准单元库的数字集成电路设计流程和方法学。数字集成电路设计流程从行为级的HDL描述开始,依次进行系统行为级仿真,行为级综合,RTL仿真,逻辑综合,综合后仿真,自动化布局布线,版图后仿真等步骤。讨论了如何把物理设计环境和逻辑设计环境联系起来,以解决物理设计和逻辑设计相脱节的问题。  相似文献   
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This paper designs a class of Fuzzy Petri net controller based on the character of place invariant in Petri net. This controller is simple in operation and is easy to put into practice. It has satisfying effects and can provide methods to do research in designing and optimizing the performance of system in solving the dead lock phenomenon in concurrent system.  相似文献   
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Alleviating the degradation issue of Pt based alloy catalysts, thereby simultaneously achieving high mass activity and high durability in proton exchange membrane fuel cells (PEMFCs), is highly challenging. Herein, we provide a new paradigm to address this issue via delaying the place exchange between adsorbed oxygen species and surface Pt atoms, thereby inhibiting Pt dissolution, through introducing rare earth bonded subsurface oxygen atoms. We have succeeded in introducing Gd−O dipoles into Pt3Ni via a high temperature entropy-driven process, with direct spectral evidence attained from both soft and hard X-ray absorption spectroscopies. The higher rated power of 0.93 W cm−2 and superior current density of 562.2 mA cm−2 at 0.8 V than DOE target for heavy-duty vehicles in H2-air mode suggest the great potential of Gd−O−Pt3Ni towards practical application in heavy-duty transportation. Moreover, the mass activity retention (1.04 A mgPt−1) after 40 k cycles accelerated durability tests is even 2.4 times of the initial mass activity goal for DOE 2025 (0.44 A mgPt−1), due to the weakened Pt−Oads bond interaction and the delayed place exchange process, via repulsive forces between surface O atoms and those in the sublayer. This work addresses the critical roadblocks to the widespread adoption of PEMFCs.  相似文献   
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