面向LOFAR应用的160Gbit/s OTDM 试验平台

报告了一个用于低频射频天线网络LOFAR的160 Gbit/s 演示平台.文章介绍了LOFAR网络结构以及用于LOFAR长臂的OTDM/WDM系统结构，回顾并探讨了用于实现160 Gbit/s系统的关键技术，并介绍了实验室中实现该160 Gbit/s OTDM/WDM演示平台所采用的技术方案。出于经济性考虑，所有的关键系统功能都采用自己搭建方案.     

A Prototype laser forming system

A non-contact laser forming (LF) demonstrator system was developed to demonstrate the process on a large primitive shape. The research that led to this development is described in this article. A fundamental study was carried out which examined the effects of laser-forming parameters on tokens of an aluminium and a titanium alloy. Energy, geometrical and metallurgical influences were investigated and are summarised here. Results of the study showed that LF of these aerospace materials is possible using a large operating envelope of laser-processing parameters. A range of metallurgical effects resulted on the titanium alloy and these are traced here. Depending on how the energy input was supplied to the plate surface, various geometrical effects resulted. These effects are discussed. Using the knowledge gathered from the fundamental study, a prototype LF system was built. The components of the system and the forming of a primitive shape on it are discussed. Conclusions from the study indicate that the future work lies in the development of the demonstrator for primitive 3-D shapes and the integration of a knowledge-based system.     

Experimental demonstration of the operation process of a pulse-detonation liquid rocket engine

A low-frequency demonstrator of the operation process of a pulse-detonation liquid-fuel rocket engine, intended for shaping the future design of a new type of rocket engines for spacecraft control, is for the first time developed and tested. As a result, the conditions are determined under which the demonstrator provides reliable deflagration-to-detonation transition (DDT) in a single-pulse or repetition mode. Because DDT occurs within a very short distance (less than 10 bores of the detonation tube), the operating frequency of the demonstrator can be substantially increased.     

可调频率的热声振荡演示器的研制

基于热声理论,介绍了一种相对于传统热声振荡演示器更为简单、有效、直观的热声振荡演示装置,该装置除可调节声波振幅外,还可以调节声波的频率。该装置有助于更好地理解热声效应,了解影响热声振荡的因素,为进一步的深入研究奠定基础。     

Mathematical morphology operations with a comparator array processor

We present a demonstrator photonic system for mathematical morphology image processing. Optically interconnected arrays of differential pairs of optoelectronic transceivers realize morphological erosion and dilation in an 8x8 pixel size image.     

流线演示仪的制作及应用

利用有机玻璃、排水管、水阀染料容器板等制作了流线演示仪,采用对工作液体染色的方法,避免了工作液体和有色液体的压力差.利用本仪器,对圆形障碍物、流线体和机翼模型周围的流线进行演示,流线稳定、清晰.     

弹簧摆动力学行为演示仪

在非线性保守系统中,弹簧摆结构简单,运动特性较为典型.本文通过拉格朗日方程对弹簧摆系统进行理论分析解得运动方程,并在径向和切向将运动分解,运用图像处理技术设计制作了弹簧摆演示仪和实验软件,对运动轨迹与时序图进行可视化.软件绘制的弹簧摆轨迹与理论结果具有较好的一致性.     

多轨道最速落径演示装置

设计制作了基于STC89C52RC单片机的多轨道最速落径演示装置,通过对电磁铁和显示屏的自动控制,将测量数据直接由数码管显示。多轨道对比演示、即时显示数据,达到了直观演示最速落径问题的设计目的。     

麦克斯韦速率分布演示仪的精确设计

本文提供了一个精确设计麦克斯韦速率分布演示仪的理论方法,可以精确计算出伽尔顿模板底部的滑行曲线.以铊原子蒸汽的麦克斯韦速率分布为实例设计演示仪,给出滑行曲线的解析式.     

光纤陀螺演示仪

介绍了光纤陀螺仪的工作原理及设计要求,根据教学实际,设计了光纤陀螺演示仪。     

刚体转动瞬心极迹动态关系的演示教具

介绍一种演增刚体平面平行运动转动瞬心极迹动态关系的教具,可清晰在一幅画面上演示瞬心位置移动所描绘出的空间极迹和本体极迹以及三者之间的动态关系,教具结构简单易于制作,轻便易于携带。     

Thrust characteristics of a pulse detonation engine operating on a liquid hydrocarbon fuel

A demonstrator of a pulse detonation combustion chamber of original design based on a cyclic deflagration- to-detonation transition in a mixture of separately fed liquid hydrocarbon fuel (propane–butane mixture) and air was developed. Fire tests of the demonstrator with an attached air duct, operating frequencies of up to 20 Hz, were performed on a thrust measurement bench. During the tests, wave processes in the gasdynamic duct were monitored and fuel consumption rate and thrust force were measured. At a frequency of operation of the demonstrator within 2–15 Hz, the fuel-based specific impulse was ~1000 s. It is shown that a partial filling of the gasdynamic duct with fuel mixture makes it possible to increase the specific impulse up to ~1100 s.     

对电动向心力定量分析演示仪的改进

针对现有"向心力演示仪"实验的不足,对电动向心力定量分析演示仪进行改进,新仪器保留了电动向心力演示仪的部分元件,改进了转动半径测量和向心力测量装置.通过改变电动机转速、圆周运动半径、金属球质量等参量,该装置可定性演示向心力和定量研究向心力表达式.     

小型风光互补发电演示装置

研制了适用于大学物理演示实验教学的小型风光互补发电演示装置,该装置由叶片、风力发电机、光伏太阳能电池板、控制器、蓄电池、逆变器、负载等几部分组成.整个系统以光电互补控制器为核心,经由风力发电机与光伏太阳能电池板将风能和太阳光能转变为电能,并将其储存于蓄电池中供负载使用.该装置展示了风力发电系统的组成,演示了风力发电原理和相关空气动力学原理.     

Design of a space borne optical aperture synthesis system for high resolution astronomy

This paper proposes a design for a space borne demonstrator interferometer with imaging capabilities. This demonstrator would be a first step in the development of an operational astronomical instrument using aperture synthesis.Multiple aperture interferometry is a promising technique for high resolution imaging in space. Indeed the use of modular elements based on optical fibres represents an attractive low cost approach.The instrument is based on the use of independent triplets of telescope linked with optical fibres. For each triplet, only the phase closure of the system is measured. This does not require an accurate cophasing of the apertures and leads to realistic stability and control specifications. The complete instrument is then built by adding the desired number of such triplet modules. The detailed design of one module is described starting at level of the receiving telescopes down to the focal plane where the control of the stability of the optical path differences is performed as well as the scientific observations. The global operation of the system will also be described.We also briefly recall the technology validation activities which have shown on the ground the feasibility and performance of all components of such a systems as well as its end to end validation.     

激光全息演示仪

为了在不具备昂贵的全息防震台和完备的光学器件的条件下,也能有一种比较理想的教学仪器,能够实现各种全息像的再现演示,本文介绍了这种激光全息演示仪的原理和结构设计。     

珀尔贴效应演示仪的研制

本文介绍了半导体致冷器件的原理,并依此原理研制了一台珀尔贴效应教学演示仪。     

对超重、失重实验的改进

本文介绍了利用发光显示超重、失重演示器的直观性效果好的特点。     

谈多功能波动演示仪的研制与应用

本文从仪器的结构、原理及使用三方面介绍了最新研制的多功能波动演示仪及其应用。