声波远探测测井与地震缝洞精细评价技术研究*

地震勘探探测范围广、空间尺度大,数据采集、处理、解释体系完善,资料运用率高,但纵向分辨率低。声波远探测可实现井周数十米范围内的异常体探测,克服了常规测井方法探测深度浅的局限,具有很高的纵向、周向、径向分辨率,但偶极横波远探测具有180°方位不确定性,径向探测范围不及地震勘探。本研究将两者优势结合,通过对缝洞型地质异常体远探测和地震响应特征进行综合分析,约束远探测方位解释结果,精细刻画地质异常体形态及发育情况,完善远探测测井的横向延伸信息,有效提高远探测解释的精准度,最终形成声波远探测测井与地震一体化缝洞综合评价技术,提升缝洞油气藏钻遇率和开发效率。在塔河等缝洞发育地区进行应用,实现多尺度、全方位和高精度的地质异常体描述与解释,为解决油气勘探过程中由于地震分辨率不足造成的脱靶等现象提供了新的思路。     

一种嵌入式软件逻辑覆盖测试方法研究

针对嵌入式软件测试覆盖率低的问题,本文提出了基于软件故障注入的逻辑覆盖测试方法,首先就嵌入式系统常用传感器建立故障模式库,设计了嵌入式软件故障注入系统;其次选取中间层作为故障注入点,研究基于VxWorks653嵌入式操作系统的故障注入实现方式,并通过分析故障信号在软件系统中的传播,提出优化测试用例的方法;最后通过实验验证了该方法可有效提高容错设计功能、冗余设计功能、故障检测功能测试的逻辑覆盖率;有助于提高嵌入式软件的可靠性。     

基于CPCI总线的雷达导引头测试系统设计与实现

雷达导引头是空空导弹的核心部件,实现导弹探测、制导和控制等功能,其性能的优劣直接影响着导弹跟踪和截获目标的准确率。为了全面测试空空导弹雷达导引头,设计开发了一种基于CPCI总线的雷达导引头测试系统,并完成了软硬件设计。硬件部分完成了调理电路的设计、外设的搭建以及硬件电路方面的可靠性设计;软件部分协调控制雷达导引头、角位置模拟器、回波模拟器和转台,通过部件之间数据流的传输,完成了各个模块的测试功能。该系统能够真实模拟雷达导引头的工作环境,设置导引头参数,接收处理导引头发回的信息,进而测试雷达导引头的精度、灵敏度、可靠性等指标。实际应用表明,该系统工作性能良好,可靠性高,能够长期稳定运行,达到了设计要求。     

基于时分复用技术的组网地基雷达半实物仿真系统[BT)]

该套基于时分复用技术的组网地基雷达半实物仿真系统,包括L波段雷达半实物系统、P波段雷达以及P波段雷达功能级数学模型。三个系统联合工作,更加完整的模拟战场元素,提高了仿真逼真度与可信度。此外针对半实物模型与功能级数学模型应用时分复用技术,缩减了设备成本,简化了试验方法,降低了试验难度。     

面向PC的实时读出系统二维图象处理及其集成交互软件

通用个人计算机及其显示系统的发展,使得以通用微机开发特定仪器设备专用的小型图象处理系统成为可能,本文提出一个基于通用PC机TVGA/SVGA显示系统的二维图象处理集成交互式软件系统,该系统以PC机为基础,结合CCD摄象机、视频图象采集与帧存储器以及控制接口一起构成变象管相机实时读出系统,用于执行读出系统控制、图象采集输入、图象处理和分析、结果输出和图象及其相关特征文件管理等功能;在结构和处理方法上,该软件系统的设计充分利用了TVGA的硬件特点和图象处理与分析领域的最新成果;包括黑白和伪彩色互换显示,自适应顺序统计量滤波、最小二乘阈值自调节图象分割技术及ARC图象数据压缩存取等;系统采用多层弹出式菜单和窗口技术,向用户提供了简明方便的交互式用户接口,具有丰富的通用图象处理分析功能,除支持变像管相机读出所需的各种专门处理与分析外,还可作为通用的二维图象分析系统,具有广泛的适用性。     

受损限幅器的非线性效应对成像雷达的影响

在复杂电磁环境下,当电子学系统的关键器件遭受功能或物理损伤而发生非线性效应时,会导致电子学系统的探测性能下降,严重时可能使系统无法实现预期的功能。以一种对地成像雷达的限幅器为对象,研究了限幅器损伤后的非线性特性信号模型构建方法,较为深入地研究了它对雷达信号处理的影响。理论和仿真分析结果表明,典型电子学系统在关键器件发生非线性变化的情况下,会明显降低成像雷达的性能,如成像不能聚焦和分辨率下降等。     

三维非均匀不稳定渗流方程的自适应网格粗化算法

将渗透率自适应网格技术应用于三维非均匀不稳定渗流方程的网格粗化算法中,在渗透率或孔隙度变化异常区域自动采用精细网格,用直接解法求解渗透率或孔隙度变化异常区域的压强分布,在其它区域采用不均匀网格粗化的方法计算,即在流体流速大的区域采用精细网格.用该方法计算了三维非均匀不稳定渗流场的压降解,结果表明三维非均匀不稳定渗流方程的三维非均匀自适应网格粗化算法的解在渗透率或孔隙度异常区的压强分布规律与采用精细网格的解非常逼近,在其它区域压强分布规律与粗化算法的解非常逼近,计算速度比采用精细网格提高100多倍.     

基于PXI总线和SCPI程控的某型雷达通频带测试系统设计

文章主要研究了基于PXI总线和SCPI命令的雷达通频带测试系统,该测试系统由虚拟仪器库、性能测试模块、仪器程控模块、性能测试流程管理模块、测试结果分析模块5个部分组成;文章详细描述了测试系统的软硬件组成,并对测试的数据进行处理分析,提出了改进雷达通频带测试结果的具体算法,该算法能有效的滤除测试结果中的飞点,在对中心频率为28.5MHz、通频带为1.5MHz的雷达通频带性能测试中取得理想效果;基于本系统,能实现雷达通频带性能测试的自动化,降低对操作人员的依赖程度,并能极大地减少测试时间、提高测试的精度。     

基于TS201的网络化声纳信号处理平台设计

凭借出色的浮点运算性能,TS201芯片在声纳、雷达等军用电子设备中得到了广泛的应用。然而,由于该芯片本身没有提供原生的高速串口(如串行RapidIO,GbE),不利于多DSP系统接入到网络和实现功能的可重构。本文提出了一种设计方法:利用串行RapidIO技术将TS201芯片构建成可重构的网络,实现了基于TS201芯片信号处理平台的网络化,提高了系统的通用性和使用效率。     

一种NMR谱仪控制台软件系统的多层架构设计

提出了一种用于核磁共振（Nuclear Magnetic Resonance, NMR）谱仪控制台软件系统的多层架构设计. 该设计在逻辑功能上将系统抽象为Linux硬件设备驱动、驱动接口、业务逻辑、网络传输和协议控制5层,每一层完成系统中特定的功能,并且独立维护. 这种采用分层的设计方式降低了系统的耦合性,简化了系统结构; 并且能多层同时开发,提高了编程效率,缩短了开发周期. 严格测试后,该软件系统与实验室自主研发的硬件联合调试,运行良好,能够长期稳定的进行实验操作,满足设计要求.     

Guided-Wave Two-Dimensional Acousto-Optic Scanner Using Proton-Exchanged Lithium Niobate Waveguide

Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.     

Effect ofγ-radiation on the spectral luminescence characteristics of impure cadmium tungstate crystals

Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·10⁴ Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.     

Femtosecond Transform-Limited Pulse Generation by Compensating for the Linear Chirp of SPM Spectra in Dispersion Shifted Fibers

A simple technique of pulse compression, based on the linear chirp compensation of self-phase modulation (SPM) spectra in dispersion shifted fibers, is demonstrated. The optimization procedure is carried out, for a short span of a single-mode fiber, using a parabolic law, which describes the behavior of the squared output pulse width versus the pump peak power in the case of Gaussian pulses. The experimental results give a minimum pulse duration of 233 fs, which is in good agreement with the model. Shorter and coherent pulses, down to 90 fs, have been obtained by inserting an interference filter at the optical output.     

Sorting of bending magnets for the SSRF booster

The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper.     

Measurement of nonlinear coefficient of optical fiber based on small chirped soliton transmission

We measure the waveform and phase curves of short optical pulses before and after transmission over different lengths of fibers by use of the pulse analyzer with the frequency-resolved optical gating (FROG),and numerically simulate pulse evolution under the experimental conditions.The nonlinear coefficient of the fiber is given by comparing the experimental results with the numerical ones.Difference between the experiment and numerical simulation is analyzed.     

Resonance scattering of canonical elastic shells in absorbing fluid medium

Resonance scattering of elastic spherical shell and cylindrical shell while the surrounding fluid medium has absorption is studied. The normal mode solution derived using exact elastic theory and the separation of variables is still applicable. However, the scattering form function has to be modified for the absorbing medium, otherwise the unreasonable result would be obtained. The backscattering form function in the absorbing medium is redefined, and the form function of elastic spherical and cylindrical shell with vacuum or solid matter filled is calculated in various absorption conditions. The results show that the absorption of surrounding fluid leads to notable attenuation of the coincidence resonances in the mid-frequency, but it has a little influence on the low-frequency resonance scattering induced by the filler inside the shell.     

Single-beam self-referenced phase-sensitive surface plasmon resonance sensor with high detection resolution

A versatile and low-cost single-beam self-referenced phase-sensitive surface plasmon resonance(SPR)sensing system with ultra-high resolution performance is presented.The system exhibits a root-mean-square phase fluctuation of ±0.0028.over a period of 45 min.i.e.a resolution of±5.2×10-9 refractive index units.The enhanced performance has been achieved through the incorporation of three design elements:a true single-beam configuration enabling complete self-referencing so that only the phase change associated with SPR gets detected,a differential measurement scheme to eliminate spurious signals not related to the sensor response,and the elimination of retardation drifts by incorporating temperature stabilization in the liquid crystal phase modulato .Our design should bring the detection sensitivity of non-labeling SPR biosensing closer to that achievable by conventional fluorescence-based techniques.     

Influences of SiO2 protective layers and annealing on the laser-induced damage threshold of Ta2O5 films

Ta2O5 films are prepared on BK7 substrates with conventional electron beam evaporation deposition.The effects of SiO2 protective layers and annealing on the laser-induced damage threshold (LIDT) of the films are investigated.The results show that SiO2 protective layers exert little influence on the electric field intensity(EFI)distribution,microstructure and microdefect density but increase the absorption slightly.Annealing iS effective on decreasing the microdefect density and the absorption of the films.Both SiO2 protective layers and annealing are beneficial to the damage resistance of the films and the latter is more effective to improve the LIDT.Moreover,the maximal LIDT of Ta2O5 films is achieved by the combination of SiO2 protective layers and annealing.     

A stereo matching algorithm using multi-peak candidate matches and geometric constraints

Gray cross correlation matching technique is adopted to extract candidate matches with gray cross correla- tion coefficients less than some certain range of maximal correlation coefficient called multi-peak candidate matches. Multi-peak candidates are extracted corresponding to three closest feature points at first. The corresponding multi-peak candidate matches are used to construct the model polygon. Correspondence is determined based on the local geometric relations between the three feature points and the multi-peak candidates. The disparity test and the global consistency checkout are applied to eliminate the remaining ambiguous matches that are not removed by the local geometric relational test. Experimental results show that the proposed algorithm is feasible and accurate.