基于AHP法的天波超视距雷达作战效能评估模型

根据天波超视距雷达的工作特性和作战任务,运用层次分析法,给出了天波超视距雷达作战效能评估指标的层次结构,确定了各效能指标及相对权重的计算方法,得出了天波超视距雷达作战效能评估的数学模型,为该雷达的发展改进及作战使用提供辅助的决策依据。     

天波超视距雷达作战效能综合评估研究

为全面准确评估天波超视距雷达作战效能,提出了一种基于模糊层次决策的天波超视距雷达作战效能综合评估模型。建立了一种较为系统的天波超视距雷达作战效能综合评估指标体系。将层次分析法与模糊综合评判方法应用到雷达作战效能评估中,介绍了作战效能评估方法和步骤,最后以某型天波超视距雷达为例进行了实例应用与分析。结果表明,该评估模型实用有效,为天波超视距雷达的研制、改进、优化部署以及作战使用提供了辅助的决策依据。     

基于模糊网络的天波雷达作战效能评估北大核心CSCD

为克服传统天波超视距雷达作战效能评估技术的局限性,提高天波雷达作战效能评估可信度,提出了基于模糊神经网络的作战效能评估模型。该模型将神经网络、专家系统、模糊推理等技术有机结合,既能处理模糊知识,又能进行自学习,克服了人为因素和模糊随机性对评估结果的不良影响。仿真结果表明,评估结果更为合理可信,并具有良好的鲁棒性。该模型可为天波超视距雷达的研制、改进、优化部署和作战使用提供辅助决策依据。     

基于改进ADC模型的天波雷达作战效能评估

天波雷达能够在防空、反导、对海监视等多个领域发挥重要作用,已成为各大国战略预警体系中的重要装备。为全面准确评估天波超视距雷达的作战效能,结合天波雷达作战使用特点,系统分析了电离层状况和电磁环境对天波雷达的影响,建立了天波雷达作战效能评估指标体系,提出了一种改进的ADC模型。采取定量和定性相结合的评估方法,根据有效探测威力、探测精度、发现概率等指标数据,客观评定了雷达作战效能,为作战运用和装备论证提供了科学决策依据。     

基于ADC模型的天波超视距雷达作战效能评估

根据天波超视距雷达组成和任务,采用ADC效能评估模型,通过对系统的可用性向量A^T、可信性矩阵[D]、能力向量C以及抗干扰效果因子KAJ的建模,推导出天波超视距雷达系统作战效能方程。     

天波超视距雷达发展综述

本文从天波超视距雷达的机理和特点出发,论述了国外天波超视距雷达的发展历史和现状.根据新时期的作战需求和特点,重点阐述了天波超视距雷达在战略预警中的地位和作用,包括防空、反导和对海监视.从系统设计、信号处理及数据处理等技术领域,对天波超视距雷达发展趋势和关键技术进行了评述,提出了当前主要研究方向和热点,并对相应的技术途径...     

天波超视距雷达中流星余迹干扰模型

已获得的实测数据表明,天波超视距雷达在3MHz-30MHz的工作频段内存在明显的流星余迹干扰.流星余迹干扰会对天波超视距雷达探测目标的距离和多普勒信息造成负面影响,严重时会影响到天波超视距雷达的正常工作.根据流星余迹的散射特性,结合天波超视距雷达的工作方式,建立了流星余迹干扰模型,为在天波超视距雷达中研究抑制流星余迹干扰技术提供了帮助.仿真结果与实测数据基本一致,验证了模型的有效性.     

基于灰色理论的机载预警雷达效能评估技术

以机载预警雷达为研究对象,提出基于灰色系统理论的效能评估模型。采用层次分析法建立多层次效能评估指标体系结构,确定评估体系指标权重。通过专家对指标评分,建立评估指标值矩阵,运用灰色系统理论进行计算,给出4种型号主要机载预警雷达效能评估代数值。结果表明,利用该方法对机载预警雷达效能进行评估是可行的,评估结果也可为发展机载预警雷达提供一定的借鉴。     

电离层Es 层对天波超视距雷达性能影响研究

电离层突发E 层(Es 层)是我国夏季经常出现的一种电离层不均匀结构。文中提出了一种基于背景电离层特性的Es层电子浓度分布模型,开展了电离层Es 层对天波超视距雷达影响的仿真分析,获得了雷达探测威力特性分布。试验仿真表明,该方法与实际情况的一致性较好。电离层Es 层模型可以为天波超视距雷达性能评估和决策支持提供理论依据。     

战斗机对空作战效能评估

当前对战斗机的能力评估已经从关注其性能发展到关注其效能上,研究人员一直在努力探索如何对战斗机作战效能进行评估。根据现代空战模式将空战过程分解为超视距空战和视距内空战,并分别对作战飞机进行作战效能评估。针对战斗机的隐身性,提出雷达探测能力、被动雷达探测能力和红外探测能力作为超视距空战中态势感知能力的指标。对于超视距空战和视距内空战的作战效能评估均采用层次分析法,并给出计算各项子能力的计算模型。     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Nanoimprint Lithography -A Next Generation High Volume Lithography Technique

IntroductionNanoimprint Lithography is a well-acknowl-edged low cost, high resolution, large area pattern-ing process. It includes the most promising methods,high-pressure hot embossing lithography (HEL) [2],UV-cured imprinting (UV-NIL) [3] and micro contactprinting (m-CP, MCP) [4]. Curing of the imprintedstructures is either done by subsequent UV-lightexposure in the case of UV-NIL or by cooling downbelow the glass transition temperature of the ther-moplastic material in case of HEL…     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

Influence of PVK ： NPB hole transporting layer on the characteristics of organic light-emitting devices

A doping system consisting of NPB and PVK is employed as a composite hole transporting layer （CHTL）. By adjusting the component ratio of the doping system, a series of devices with different concentration proportion of PVK ： NPB are constracted. The result shows that doping concentration of NPB enhances the competence of hole transporting ability, and modifies the recombination region of charge as well as affects the surface morphology of doped film. Optimum device with a maximum brightness of 7852 cd/m^2 and a power efficiency of 1.75 lm/W has been obtained by choosing a concentration proportion of PVK ： NPB at 1：3.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.     

Analysis of error performance on Turbo coded FDPIM

Due to variable symbol length of digital pulse interval modulation（DPIM）, it is difficult to analyze the error performances of Turbo coded DPIM. To solve this problem, a fixed-length digital pulse interval modulation（FDPIM） method is provided. The FDPIM modulation structure is introduced. The packet error rates of uncoded FDPIM are analyzed and compared with that of DPIM. Bit error rates of Turbo coded FDPIM are simulated based on three kinds of analytical models under weak turbulence channel. The results show that packet error rate of uncoded FDPIM is inferior to that of uncoded DPIM. However, FDPIM is easy to be implemented and easy to be combined, with Turbo code for soft-decision because of its fixed length. Besides, the introduction of Turbo code in this modulation can decrease the average power about 10 dBm, which means that it can improve the error performance of the system effectively.     

A method for calculating the center position of collimated light

It is a key problem to accurately calculate beam spots＇ center of measuring the warp by using a collimated laser. A new method, named double geometrical center method （DGCM）, is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device （CCD） is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What＇s more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.