Ultra-high speed all-optical shift registers and their applications in OTDM networks

All-optical shift registers are basic building modules for the development of ultra-high speed optical time division multiplexing networks. In this paper, we review the progress that has been made in this cutting-edge technology, focusing on implementations that exploit the attractive features of semiconductor optical amplifier (SOA)-based interferometric configurations. We present regenerative storage performed with an all-optical recirculating shift register with an inverter at 10 Gb/s using a SOA-assisted Sagnac switch and a second SOA to provide feedback. We demonstrate also an all-optical memory based on the SOA-assisted Ultrafast Nonlinear Interferometer capable of reading/writing 20 Gb/s packets of variable length without data inversion. These registers can find application in the development of two nontrivial complex all-optical circuits of enhanced functionality. The first is an all-optical pseudorandom binary sequence generator for which we describe an efficient design algorithm and propose ways for monitoring and verification. The second is an all-optical error counter for which we address the error detection and evaluation issues using a novel sampling technique. These circuits are key elements for the implementation of a high-speed, all-optical bit error rate tester (BERT), which has the potential to outperform its electronic equivalent and constitute a possible new product for the telecommunications industry.     

摩擦磨损试验机模拟活塞环-缸套摩擦行为的功能开发

参考活塞环-缸套的实际运行条件,结合SRV-4摩擦磨损试验机自身的性能特点和工作原理,通过开发设计,增加合理的硬件及软件测试条件,实现摩擦磨损试验机模拟活塞环-缸套摩擦行为的功能.系统测试结果表明：功能开发后的摩擦磨损试验机可在较短时间内获得活塞环-缸套摩擦副性能优劣的试验数据,满足快速、直观评价活塞环-缸套的摩擦磨损性能的需要,在活塞环-缸套摩擦副研究中具有重要的应用价值.     

自动安全甲基紫试验仪的性能试验

介绍自动安全甲基紫试验仪的性能试验方法及试验过程。自动安全甲基紫试验仪由金属恒温浴、机械手、控制系统等构成。控制系统不但可以控制机械手、恒温浴,还可通过传感器感知、记录试纸颜色变化,监测试验过程。用该自动试验仪测试某双基和三基火药的化学安定性,与非自动甲基紫试验装置检测结果一致,重复性优于旧装置。自动安全甲基紫试验仪可有效保障操作人员的人身安全,保证检测结果的准确度,可用于测试硝酸酯火药及硝化棉的化学安定性。     

On the Elastic Modulus of Powders

For the design of silos and similar equipment for storage, handling and processing of particulate materials, a thorough understanding of the mechanical behaviour of powders is of great importance. Whereas strength properties of powders have been investigated by many workers, the elastic behaviour at small deformations has been much less in focus. In that respect, a simple preliminary theory of uniaxial elasticity has been derived for particles, based on a simple system of spherical and monosized particles of a homogenous and elastically isotropic material. The equation σ = E_p?_el² gives the relationship between stress, elastic modulus and elastic deformation for the unloading of a given powder at a specific consolidation stress/ compression level. Comparisons with experimental results of real powders in a uniaxial tester show surprisingly good agreement in many cases. The equation seems to describe the elasticity of powders fairly well, although it is only a preliminary derivation based on simple considerations.     

光栅传感器在弹簧测试仪中的应用

用弹簧测试仪对弹簧的特性进行测试和控制是保证产品质量的重要措施。弹簧测试仪由测试工作台和测试系统组成,工作台采用组合式结构,测试系统采用主从式结构,主机和从机之间通过RS-232串口实现通讯。采用应变式力传感器和光栅传感器分别对弹簧力和弹簧变形进行了测量。应用虚拟仪器技术对系统进行了设计,采用了多种软、硬件相结合的抗干扰措施。结果表明,研制的弹簧测试仪具有操作方便、人机交互友好、速度快、测试精度高、性能稳定等特点。     

闪光有效光强测定仪研究

论述闪光光源有效光强的测量方法及原理，并详细介绍我所自行研制的闪光有效光强测定仪。文中对仪器的工作原理，结构特点，技术性能和用途给予比较全面的论述，并给出了实测曲线。     

用光速测定仪探究水的折射率

用光速测定仪探究折射率是测量介质折射率的一种方法。本实验特别适合液体折射率的研究,我们以水为参考尝试测量它的折射率。     

Applying Bayesian neural networks to identify pion, kaon and proton in BES Ⅱ

The Monte-Carlo samples of pion, kaon and proton generated from 0.3 GeV/c to 1.2 GeV/c by the 'tester' generator from SIMBES which are used to simulate the detector of BES Ⅱ are identified with the Bayesian neural networks (BNN). The pion identification and misidentification efficiencies are obviously better at high momentum region using BNN than the methods of X2 analysis of dE/dX and TOF information.The kaon identification and misidentification efficiencies are obviously better from 0.3 GeV/c to 1.2 GeV/c using BNN than the methods of X2 analysis. The proton identification and misidentification efficiencies using BNN are basically consistent with the ones of X2 analysis. The anti-proton identification and misidentification efficiencies are better below 0.6 GeV/c using BNN than the methods of X2 analysis.     

对MM-200型磨损试验机摩擦系数计算公式的修正

对ＭＭ－２００型磨损试验机摩擦系数计算公式重新进行了推导和计算,所得公式与原公式相比可降低求解摩擦系数时的误差．原公式在试环与试块之间的接触角增大时,误差也随之增大,使得试验数据的可靠性和可比性严重降低,因此必须对原计算公式进行修正．     

纤细管道内壁质量检测仪的光学系统特性研究

本文对纤细管道内壁质量检测仪的光学系统成像特性进行全面分析，并对实际设计中存在的问题提出解决的有效途径。