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Polyetherimide (PEI) substrate for next‐generation high density optical data storage is fabricated and characterized. Cover‐layer incident or first‐surface recording configurations do not require optical properties of the substrate, which are the prerequisite conditions for the conventional material of polycarbonate (PC). Instead of the optical properties, good mechanical properties with a sufficient transcribability are required. Even though PEI has higher glass transition temperature than that of PC, a microscopic transcribability of PEI is comparable with PC by laminating a thermal insulation layer on the backside of a stamper to retard the heat flow. A macroscopic warpage of PEI substrate is smaller than that of PC substrates, which reduces tilt and servo burden. The lowest critical speed coupled with the flutter of PEI substrate is larger than that of PC substrate because of the mechanical properties of PEI. POLYM. ENG. SCI., 48:97–101, 2008. © 2007 Society of Plastics Engineers  相似文献   
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Discovering unknown adverse drug reactions (ADRs) in postmarketing surveillance as early as possible is highly desirable. Nevertheless, current postmarketing surveillance methods largely rely on spontaneous reports that suffer from serious underreporting, latency, and inconsistent reporting. Thus these methods are not ideal for rapidly identifying rare ADRs. The multiagent systems paradigm is an emerging and effective approach to tackling distributed problems, especially when data sources and knowledge are geographically located in different places and coordination and collaboration are necessary for decision making. In this article, we propose an active, multiagent framework for early detection of ADRs by utilizing electronic patient data distributed across many different sources and locations. In this framework, intelligent agents assist a team of experts based on the well‐known human decision‐making model called Recognition‐Primed Decision (RPD). We generalize the RPD model to a fuzzy RPD model and utilize fuzzy logic technology to not only represent, interpret, and compute imprecise and subjective cues that are commonly encountered in the ADR problem but also to retrieve prior experiences by evaluating the extent of matching between the current situation and a past experience. We describe our preliminary multiagent system design and illustrate its potential benefits for assisting expert teams in early detection of previously unknown ADRs. © 2007 Wiley Periodicals, Inc. Int J Int Syst 22: 827–845, 2007.  相似文献   
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含V、N无缝钢管表面外折缺陷产生原因的分析   总被引:1,自引:0,他引:1  
通过对鞍钢生产的部分批号V、N微合金强化无缝钢管及生产该钢管的原料连铸坯和连轧管坯的表面缺陷进行研究,分析了含V、N钢管表面外折缺陷的成因,提出了改善钢管表面质量的方法。采用改进后工艺生产的无缝管,其表面外折废品量大幅度降低。  相似文献   
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For pt.I see IEEE Trans. Neural Networks, vol.1, p.167-78 (1990). Parallel, self-organizing, hierarchical neural networks (PSHNNs) involve a number of stages with error detection at the end of each stage, i.e., rejection of error-causing vectors, which are then fed into the next stage after a nonlinear transformation. The stages operate in parallel during testing. Statistical properties and the mechanisms of vector rejection of the PSHNN are discussed in comparison to the maximum likelihood method and the backpropagation network. The PSHNN is highly fault tolerant and robust against errors in the weight values due to the adjustment of the error detection bounds to compensate errors in the weight values. These properties are exploited to develop architectures for programmable implementations in which the programmable parts are reduced to on-off or bipolar switching operations for bulk computations and attenuators for pointwise operations  相似文献   
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This paper presents a method of obtaining transmission network equivalents from the network's response to a pulse excitation signal. The proposed method is based on modal decomposition representation for the large-scale interconnected system. In this framework we use Prony analysis to identify the network function of the system and to decompose the large system into a parallel combination of simple first-order systems. As a result the network function of the transmission network can be identified easily, and a Thevenin-type of discrete-time filter model can be generated. It can reproduce the driving-point impedance characteristic of the network. Furthermore, the proposed model can be implemented into the EMTP in a direct manner. The simulation results with the full system representation and the developed equivalent system showed a good agreement  相似文献   
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There is no good method to measure the shape and the strain distributions of a structure changing with time. We have previously proposed the Fourier transform grid method (FTGM) to measure the three-dimensional shape and surface strain distributions of stationary objects by analysing the two-dimensional grating images recorded with two cameras. In the stereoscopic method, it is very important to determine the accurate geometric parameters of the camera system. In this paper, the positions and the directions of cameras are accurately determined using the FTGM applied to images of a reference object on which a two-dimensional grating is drawn. Applications for analysing shape and strain distributions of vibrating rubber plates and a moving human skin are shown.  相似文献   
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曹红梅 《山西建筑》2003,29(18):34-35
介绍了阳泉市煤矿采空区对公路建设所造成的危害,对其上覆岩层变形破坏的地质因素及其破坏机理作了分析,指出应该采取各种措施减少对公路的破坏。  相似文献   
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