Figure of merit for the quality of ZrO2 coatings on stainless steel and nickel-based alloy surfaces

A figure of merit (FOM) has been developed to define the quality of ceramic (e.g., ZrO₂) coatings on metal and alloy [Type 304SS and Alloy 600] surfaces. Zirconia (ZrO₂) coatings were developed as a means of protecting the metal/alloy surfaces from stress corrosion cracking (SCC) in boiling water reactor (BWR) primary heat transport circuits, by inhibiting the cathodic reaction (reduction of oxygen and hydrogen peroxide) on the surface external to the crack. The distribution of pores in the coating plays an important role in corrosion prevention, such that the lower the porosity of the coating, the better the protection afforded to the system against SCC. Since the reactors operate at high temperature (e.g., at 288 °C under full power conditions), the temperature dependence of the FOM was investigated. The figure of merit (FOM) was developed by measuring impedance data over a wide range of frequency (10 mHz-5 kHz) at temperatures of 25, 100, 200, and 288 °C in hydrogenated, buffered solutions, with the hydrogen electrode reaction (HER) being used as a “fast” redox couple. An “equivalent circuit” analog was first developed from the bare surface impedance data and this analog was then employed in a second step to model the pore bottom in defining the pore distribution on the coated surface. A lognormal distribution (LND) of the pores was assumed and the parameters of the LND were determined using a constrained optimization technique to fit the model to the experimental data for the coated surface at different temperatures. The results suggest that, as temperature increases, the coating becomes more porous, making the substrate more susceptible to corrosion cracking. At 288 °C, 87% of the SS and 85% of the Ni-alloy surfaces become porous with the pore radius varying from 0.0001 cm to 0.01 cm.     

基于HLA的海航作战仿真系统设计研究

首先对基于高层体系结构（HLA）的海航作战仿真系统进行了介绍和分析,在分析作战特点的基础上,依据HLA的体系结构规范,构建了海航作战仿真系统的体系结构框架,并利用统一建模语言（UML）,完成了系统对象类和交互类模型设计,研究了仿真成员代码实现的方法,对航空兵作战仿真的进一步研究和系统开发具有一定的借鉴意义。     

High Figure of Merit (FOM) of Bragg Modes in Au‐Coated Nanodisk Arrays for Plasmonic Sensing

Gold‐coated nanodisk arrays of nearly micron periodicity are reported that have high figure of merit (FOM) and sensitivity necessary for plasmonic refractometric sensing, with the added benefit of suitability for surface‐enhanced Raman scattering (SERS), large‐scale microfabrication using standard photolithographic techniques and a simple instrumental setup. Gold nanodisk arrays are covered with a gold layer to excite the Bragg modes (BM), which are the propagative surface plasmons localized by the diffraction from the disk array. This generates surface‐guided modes, localized as standing waves, leading to highly confined fields confirmed by a mapping of the SERS intensity and numerical simulations with 3D finite element method. The optimal gold‐coated nanodisk arrays are applied for refractometric sensing in transmission spectroscopy with better performance than nanohole arrays and they are integrated to a 96‐well plate reader for detection of IgY proteins in the nanometer range in PBS. The potential for sensing in biofluids is assessed with IgG detection in 1:1 diluted urine. The structure exhibits a high FOM of up to 46, exceeding the FOM of structures supporting surface plasmon polaritons and comparable to more complex nanostructures, demonstrating that subwavelength features are not necessary for high‐performance plasmonic sensing.     

Co掺杂对Ba0.6Sr0.4TiO3薄膜介电性能的影响

利用溶胶凝胶工艺在Pt/TiO2/SiO2/Si衬底上制备了Co掺杂量为0～10%(摩尔分数)的(Ba0.6Sr0.4) Ti1-xCoxO3薄膜.研究了薄膜的结构、表面形貌、介电性能与Co掺杂量的关系.薄膜的介电损耗随着Co含量的增加而减少,在摩尔含量10%时达到最小值0.0128.FOM值在摩尔含量为2.5%达到最大值20,它的介电常数、介电损耗和调谐量分别为639.42、0.0218、43.6%.     

HLA的分布式仿真体系在动力系统中的应用研究

高层体系结构HLA以其突出的互操作性和可重用性,成为当今分布式交互仿真系统结构标准,研究基于HLA的仿真程序设计方法对于分布式交互仿真系统的开发具有重要意义。该文首先简要介绍了高层体系结构的组成,然后分析了基于HLA的仿真应用系统的开发过程。最后,以三轴燃气轮机为例,从应用的角度分析了基于HLA的仿真系统开发过程和方法。     

基于FPGA的16E1光纤复接系统

提出并设计了一种低成本，2-16个E1单步复接，采用单片FPGA实现，通过光纤传输的中小容量数字复拉系统（FOM），作为光纤接入网的传输过渡产品，在合理定义的系统帧结构基础上，采用VHDL硬件描述语言和自顶向下的设计流程，完成了系统的核心逻辑设计，并用25万门FPGA进行了仿真和测试，证明该方案是可行的。     

FOM设计过程中的几个问题

FOM表是对联邦运行期间各联邦成员之间所交换信息的一种规范化描述，是提高模型之间互操作性和可重用性的关键技术之一，同时也是联邦开发的难点所在。该文首先对FOM的概念进行了讨论，分析了FOM中的对象与OOAD中的对象之间的异同。然后，我们在联邦开发实践的基础上，对FOM的开发过程进行了系统的总结，指出了在FOM开发过程中应该注意的问题。     

被动声纳作用距离预报的仿真研究

研究了被动声呐探测距离预报的仿真技术.声呐最大作用距离受水文条件的影响是很大的,比如声速梯度、海况、海底底质等.首先分析海洋声学环境,提出一种计算声传播损失的模型,给出了它的原理及算法,然后以声纳方程为基础,利用优质因素值建立声纳作用距离探测的预报模型,并用VC完成该仿真软件的开发.最后针对目标辐射声源级、声速分布等不同的影响因素进行仿真,并给出仿真结果,为声纳的作用距离预报提供了有价值的参考.     

一种提高Power VDMOSFET栅电荷性能的新结构

文章提出一种减小VDMOSFET栅电荷（Qg）的新结构，通过二维数值模拟：相对于常规VDMOSFET，该结构将栅电荷降低42．93％，器件优值（FOM=Qg＊Ron）降低37．05％。我们分析了新结构的主要特性，并与常规VD-MOSFET进行了比较和参数优化分析。     

基于HLA的超联邦管理的研究与实现

本文简述了HLA架构在分布式系统设计中的重要作用，分析了HLA系统的以FOM为中心的编程模型的特点及带来的开发、维护和重用问题。本文提出的HLA中的超联邦管理方法是在联邦执行的层面上对其进行控制，实现了灵活机动的仿真方式，并成功地解决了上述问题。本文还对HLA和流行的场景渲染技术的结合做了有益的尝试，对大型可视化仿真具有一定的参考价值。