频率分辨双光束耦合抽运-探测技术中的空间效应研究

在测量非线性折射率和双光子吸收系数的频率分辨双光束耦合抽运 探测技术中 ,光场的空间分布没有得到考虑。研究了入射飞秒光脉冲的空间分布对实验结果的影响。对不同部位的探测光进行测量可以得到完全不同的结果 ,用所发展的理论给出了解释。通过数值拟合获得了磷化镓 (GaP)在飞秒激光脉冲作用下的非线性折射率和双光子吸收系数。进一步可能从实验上主动选择适当的空间滤波来获得频率 空间分辨信号。     

Simulated and experimental study of hydraulic anti-lock braking system using sliding-mode PWM control

Both simulated and experimental studies of an anti-lock braking system are undertaken. A nonlinear mathematical model of the anti-lock braking system is built and a simulation is performed. Two sliding-mode controllers, one using pulse width modulation, and the other switching control, are designed and tested. Comparisons of simulated and experimental results obtained using these two control methods are discussed. Simulated results were verified on a test stand. Emergency braking controlled by a standard commercial electric control unit is also performed on the dynamic test stand and compared with the results of the designed systems. The proposed mathematical ABS model's simulated results match experimental data well.     

新的电调制反射谱技术及其应用

提出一种微接触电调制反射谱（LCER）测试方法,该方示与无接触电调制反射（CER）谱相比较,可极大降低调制电压。给出了自制的详细样品架结构,测量了InGaAs／GaAs量子阱样品,并与光调制反射谱（PR）相比较,结果证实了此方法的可行性和高光谱灵敏度,表明样品与电极的轻微接触既对测量结果没有明显的影响,又可简化测试条件,降低对测量环境的要求,是研究半导体材料和微结构一种方便而又有效的方法。     

角锥互注入锁相光纤激光器相干合成技术研究

提出角锥作为相干合成元件实现互注入锁相获得相干合成输出的方案。对比分析了采用4种锁相结构进行两路光纤激光器相干合成的结果,并报道了4路光纤激光相干合成的最新实验结果。     

波前控制技术在激光照射皮肤组织中的应用

简述了激光光束波前校正计算过程,并介绍了激光光束波前控制技术在血管性皮肤损伤中应用的前景,建立了利用改变激光波前来提高透过皮肤组织光强的实验装置,详细报道了波前控制技术用于激光照射皮肤组织的实验结果。实验结果表明在照射激光剂量不变的情况下,通过波前控制可以大幅度提高穿透皮肤的激光局部能量密度。     

Characteristics of a multimode laser diode in a dual-interferometerconfiguration

The results of an experimental investigation of an interferometric sensor scheme using a Michelson interferometer in conjunction with a Fabry-Perot reference cavity, illuminated by light from a multimode compact disk (CD)-type laser diode, are reported. The results are compared with the results of calculations using a simple theoretical model and good agreement is seen. Potential applications to interferometric-based sensors are discussed     

用计算全息再现彩色图像

介绍一种用计算全息再现彩色图像的方法，它由白光光源照明。文中给出理论分析和相应的实验结果，并对相关问题进行了讨论。     

Fuzzy associative memories for the computation of the bandwidth of rectangular microstrip antennas with thin and thick substrates

A method based on fuzzy associative memories for calculating the bandwidth of electrically thin and thick rectangular microstrip patch antennas is presented. The design parameters of the fuzzy associative memories are optimally determined by using the classical, modified and improved tabu search algorithms. The theoretical bandwidth results obtained by using the fuzzy associative memories are in very good agreement with the experimental results available in the literature.     

激光驱动飞片实验研究及其应用分析

利用小型固体激光器在100－300mJ能量范围内成功驱动了5.5μm厚度铝飞片，最高速度达到6.6km/s，实验得到飞片速度与能量密度的关系。详细介绍了实验装置，测试系统和实验方法，并对实验测试系统进行了分析。对回收样品的分析表明：飞片具有较好的平面性，完整性和重复性。对激光驱动飞片技术在模拟太空高速微粒的应用可能性进行了分析，目前的研究表明：激光驱动飞片技术可以成为一种模拟太空高速粒子的有效实验手段。     

Comparison between theoretical and measured microstrip gapparameters involving anisotropic substrates

In this paper, experimental results are presented for microstrip symmetrical-gap discontinuities. The experimental technique is based on the measurement of the resonant frequencies of several gap-coupled rectangular microstrip resonators. In particular, gap discontinuities on anisotropic dielectric and two-layer composite substrates have been investigated. Reasonably good agreement has been found in most cases between theoretical data [obtained by means of the excess charge technique in the spectral domain (EC-SDA)] and experimental data, even though the theoretical results have been obtained by using a quasi-static approach     

Current-controllable FDNRs using linear transcapacitance amplifiers

A systematic synthesis process is described for the simulation of current-controllable FDNRs using linear transcapacitance amplifiers. The process is used to obtain three circuits; two are believed to be novel. The values of the FDNRs are controllable by adjusting the bias currents of the transcapacitance amplifiers. In order to implement the obtained FDNRs, a new transcapacitance amplifier is designed. Operation principles of designed circuits are presented and experimental results are used to verify theoretical predictions. The results show close agreement between predicted behaviour and experimental performance.     

(BaSr)TiO_3晶体桥式互泵浦相位共轭器特性的研究

利用（ＢａＳｒ）ＴｉＯ３ 晶体构建桥式互泵浦相位共轭器（ＢＰＣＭ）,研究了ＢＰＣＭ 反射率随互泵浦束的入射角和泵浦比变化的实验规律。通过分析（ＢａＳｒ）ＴｉＯ３ 晶体的ｆａｎｎｉｎｇ 散射特性,利用数值计算求解相应的耦合波方程,得出反射率与互泵浦束的入射角和泵浦比的关系特性,其分析结论与实验结果一致。     

Implementation of indirect neuro-control for nonlinear dynamic systems

This paper represents identification and control designs using neural networks for a class of nonlinear dynamic systems. The proposed neuro-controller is a combination of a linear controller and a neural network trained by an indirect neuro-control scheme. The proposed neuro-controller is implemented and tested on an IBM PC-based bar system, and is applicable to many dc-motor-driven precision servo mechanisms. The algorithm and experimental results are described. The experimental results are shown to be superior to those of conventional control.     

Composite-Junction Circulators Using Ferrite Disks and Dielectric Rings

Since most junctions do not use the full available magnetic splitting of the ferrite material, it is possible to replace part of it by a dielectric. The theoretical and experimental development of such composite stripline circulators using ferrite disks surrounded by dielectric rings is given in this paper. Theoretical calculations and experimental results on the circulation frequency, gyrator admittance, and split frequencies of such circulators are included. The case of a partially magnetized ferrite disk on a ferrite substrate is treated separately. The suscteptance slope parameter of this circulator geometry is also derived and measured. The results obtained in this paper show to what extent the ferrite disk behaves as a dielectric at the edge of the disk. The geometry leads to considerable saving in ferrite material, which is particularly important in UHF circulators. The experimental results are in good agreement with the theory.     

Forward scattering from square cylinders in the resonance region with application to aperture blockage

The relationship between the induced field ratio (IFR) of a cylinder and aperture blocking of a constant-phase aperture by cylindrical struts is discussed. An analytical technique is presented whereby the IFR of rectangular cylinders can be calculated using the method-of-moments with internal constraint points. An experimental technique using a forward-scattering range is used to measure the IFR's of square and circular cylinders in an anechoic chamber. These experimental results are compared with the theory, and their implications on aperture blocking losses and boresight cross polarization are discussed.     

Theoretical and experimental analysis of thermal stress effects onmodal polarization properties of highly birefringent optical fibers

A theoretical and experimental analysis of thermal stress effects on the modal polarization properties of highly elliptical-core fibers is presented. The theoretical analysis is based on solving the vectorial Maxwell's equations, using a finite-element scheme, when form-induced and stress-induced effects are introduced simultaneously through appropriate calculation of the refractive indexes of the anisotropic media. The experimental analysis is done by studying the temperature response of a white-light interferometric sensor employing highly elliptical-core fibers. The calculated temperature sensitivities of the modal birefringence and the polarization mode dispersion in highly elliptical-core fiber are in close agreement with the experimental results. Interpretation of the results useful for designing white-light interferometric sensors composed of highly elliptical-core fibers is also given     

宽带集中元件环行器计算机辅助设计

本文从散射矩阵本征值的频率关系出发,对宽带集中元件环行器所需的设计参数作了优化计算。文中采用乘子法将约束优化问题化为无约束优化问题。计算结果与实验结果较一致并证实了为得到宽带性能实验中出现的隔离双峰的现象。     

Optimal design for direct-detection system with optical amplifiersand dispersion compensators

System performances of direct detection optical fiber communication systems with optical amplifiers and dispersion compensators are investigated theoretically and confirmed by experimental results for several different configurations. The experimental results agreed well with the calculated results. The theoretical calculation predicts that a 120-km repeaterless transmission of 10 Gb/s is possible through the standard single-mode fiber using only one commercial fiber amplifier and a dispersion compensation fiber at the receiving end     

Near-field gain of a horn and an open-ended waveguide: Comparison between theory and experiment

Generating a standard electromagnetic field requires knowledge of the gain of the transmitting antenna. The theory and supporting experimental measurements of the near-field gain of a pyramidal horn and an open-ended waveguide (OEG) at 450 MHz are given. The empirical near-field gain for the OEG is derived from experimental results obtained by a two-antenna method at about 2 GHz. The theoretical nearfield gain for the rectangular pyramidal horn is derived from Schelkunoff's formula. Two independent near-field gain measurements of these antennas are made using a three-antenna method and a transfer-standard-probe method. The discrepancy between theoretical and experimental results is typically less thanpm 1dB.