具有复合埋层的新型SIMON材料的制备

采用氮氧共注入方法制备了新型的 SIMON(separation by implanted oxygen and nitrogen) SOI材料 .采用不同的制备方法分别制作出样品并进行了结构测试和分析 ,发现 SIMON材料的结构和质量对注入条件和退火工艺非常敏感 .并对各种氮氧复合注入技术做了分析和比较 ,发现氮氧分次注入可以得到更好的结构和性能     

基于熵权的料场方案模糊多属性优选研究

砂石料场方案选择中存在着许多难以精确度量的模糊性因素，常规的平衡法、系统分析法很难对此进行有效的处理。将模糊数学理论应用于砂石料场的方案选择，提出了熵权与模糊理论相结合的砂石料场方案优选方法，重点对标准化属性矩阵的产生、主客观权重结合得到综合权重及相对接近度的计算等几个方面进行了说明，并通过实例验证了该方法的可行性与实用性。     

微波等离子体化学气相沉积的 a-Si∶H 性能研究

本文着重对微波等离子体化学气相沉积法高速沉积的 a-Si∶H 膜的物理性能进行评价研究.测量了沉积膜的光电性能、暗电导激活能、光禁带宽度、光吸收特性、沉积膜中悬键态密度以及氢含量等,并讨论沉积条件对膜性能的影响.结果表明,在沉积速率高达30～90(?)/s 情况下,膜的光电导(光照强度10~5Lux)与暗电导比值可达10~3～10~5,暗电导率从10~(-3)到10~(-11)((?)cm)~(-1),其激活能在0.23～0.88eV 之间(0～200℃温度范围内),光禁带宽度为1.40～2.20eV,氢含量约为2～20%.     

Improved coupled-mode theory for nonlinear directional couplers

An improved coupled-mode equation for nonlinear directional couplers (NLDC) with Kerr-like nonlinear media is proposed. The method is based on the generalized reciprocity relation in which two sets of field solutions satisfying Maxwell's equations are for the NLDC and for the isolated nonlinear waveguide. That leads to a reasonable result that all the coefficients in the coupled-mode equations, including the coupling coefficient, become power dependent. For the NLDC with a self-focusing or self-defocusing nonlinear material, the authors examine how the coupling coefficient, the coupling length, and the guided power depend on the input power in the range of coupling stronger than in previous reports. It is found that the critical power at which the coupling length becomes infinity does not increase as much with the two guides for the case of self-focusing media     

基于TCP/IP的入侵检测评测技术研究

入侵检测系统的评测是入侵检测研究的一个重要方面。论文研究TCP/IP协议下如何利用协议的脆弱性按层次生成评测数据,在此基础上提出了分段混合评测的入侵检测评测方法。该方法的主要思想是数据混合和评测分段。相对以往的评测方法,由于数据混合,它的评测数据更丰富、更接近现实环境,而且可以自由添加;由于评测分段,简化了评测的实现,对正常网络的干扰很小,能够生成一些特定网络中无法生成的攻击。     

The Hardness of the Closest Vector Problem With Preprocessing Over$ell_infty$Norm

We show that the closest vector problem with preprocessing (CVPP) over lscr _infin norm (CVPP_infin) is NP-hard. The result is obtained by the reduction from the subset sum problem with preprocessing to CVPP_infin. The reduction also shows the NP-hardness of CVP_infin, which is much simpler than all previously known proofs. In addition, we also give a direct reduction from exact 3-sets cover problem to CVPP_infin     

农村水电可持续发展及管理对策

农村水电具有一定的开发优势，但在开发中存在着水能资源管理缺位、部门职责不清、缺乏统一规划和统一调度管理等问题。针对这些问题,从编制流域综合规划、建立和完善水能资源许可制度、加强政府监管力度、实行统一调度、协调水电开发与生态保护的关系等方面提出了管理对策。     

CMOS artificial subretinal chip for natural light illumination

A novel CMOS oscillating pixel array for subretinal prosthesis used in natural light illumination is presented. Its prototype chips are fabricated in a standard 0.6 /spl mu/m CMOS technology. Experimental results show the device can deliver effective self-oscillation for subretinal electrical stimulation.     

Modeling transient slag-layer phenomena in the shell/mold gap in continuous casting of steel

Mold-slag friction and fracture may cause heat-transfer variations in continuous casting, which leads to steel shell temperature and stress variations, resulting in surface cracks. Analytical transient models of liquid slag flow and solid slag stress have been coupled with a finite-difference model of heat transfer in the mold, gap, and steel shell to predict transient shear stress, friction, slip, and fracture of the slag layers. The models are validated by comparing with numerical models and plant measurements of mold friction. Using reported slag-fracture strength and time-temperature-transformation (TTT) diagrams, the models are applied to study the effect of casting speed and mold-powder viscosity properties on slag-layer behavior between the oscillating mold wall and the solidifying steel shell. The study finds that liquid-slag lubrication would produce negligible stresses. A lower mold-slag consumption rate leads to high solid friction and results in solid-slag-layer fracture and movement below a critical value. Crystalline slag tends to fracture near the meniscus and glassy slag tends to fracture near the mold exit. A medium casting speed may be the safest to avoid slag fracture, due to its having the lowest critical lubrication consumption rate. The high measured friction force in operating casters could be due to three sources: an intermittent moving solid slag layer, excessive mold taper, or mold misalignment. Other symbols are defined in Table I     

自适应比例因子模糊控制器在异步电动机调速系统中的应用

为了降低转子电阻变化对异步电动机矢量控制系统性能的影响，本文把自适应比例因子模糊控制器应用到了矢量控制系统中。介绍了自适应比例因子模糊控制方法的綦本原理，给出了使用自适应比例因子模糊控制器的异步电动机矢量控制系统的结构框图，对主模糊控制器和辅助模糊控制器进行了设计。仿真实验结果表明，采用这种控制方法的调速系统不仅具有优良的动态性能，而且对转子电阻变化具有很强的鲁棒性。