蒙特卡罗方法模拟光在云雾中的传输

用蒙特卡罗方法模拟光在散射和吸收介质中的传输，得到脉冲光在云雾中运输时相对光强与传输时间的关系，从而为分辨子弹光和蛇形光提供了理论依据。     

自由空间紫外光通信系统中LED光传输模型研究

自由空间大气是紫外光通信的信道,光在大气中的传输特性直接决定了通信的质量。研究紫外LED光辐射的大气传输特性,以辐射传输理论为基础,分析了Bouguer定律的缺陷,并提出了修正方案;在单次散射原理基础上对大气中直射和斜射散射光传输特性进行了详细推导,结合LED配光曲线得出紫外LED光的大气传输解析模型。研究结果为紫外自由空间光通信系统的设计提供参考。     

三层网络交换机取代SDH光传输系统首次在海上油田的应用

随着科学技术的进步,互联网的迅速发展和社会信息化的推进,网络在规模和速度方面都在飞速发展。针对垦利项目,采取降本增效策略,提出了三层网络交换机取代SDH光传输设备的技术,主要介绍了三层网络交换机的原理、特点及与SDH光传输设备的对比分析,进一步介绍了三层网络交换机取代SDH光传输设备首次在渤海区域垦利项目中的应用。     

锥形光纤在空间光通信耦合系统中的应用

为了提高自由空间光通信的接收端耦合效率,将锥形光纤应用于光耦合,依据BPM算法的仿真结果使用熔融拉锥法制备了满足低损传输条件的锥形光纤。在实验上研究了锥形光纤和双锥形光纤模场传输特性。通过静态空间光-光纤耦合实验,对比了多/单模熔接光纤和锥形光纤光耦合效率和传输效率的差异,并研究了以上两种光纤结构耦合效率的横向偏移量容差。结果表明,锥形光纤的传输效率约为70%,具有低损传输特性、用于匹配后端单模光电子器件的良好滤波特性以及相比普通光纤更高的横向偏移量容差特性,因此可以广泛应用于自由空间光通信接收端光耦合、模式转换器等方面。     

CWDM技术在光电组合汇流环中的应用

设计了一种新型的可多路光信号同时传输的光电组合汇流环系统.该汇流环系统中光信号传输主要采用CWDM(粗波分复用)技术结合单芯光滑环来完成,具有高速率、多信道、扩展性强等特点.经过实验验证,该光纤汇流环传输系统可在各种军标要求的环境下稳定地传输多路光信号,并且信号稳定、可靠性高,在未来的雷达信号传输中具有广泛应用.     

B270-As_2S_8复合平面波导制备技术研究

为了制备As2S8波导,提出一种兼顾导波和光子作用的复合波导结构,叙述了B270-As2S8复合平面光波导的制备工艺。实验制备了复合平面光波导,采用双棱镜耦合的方法激励复合平面波导的导模,实现导模在波导中的传输,并且在复合平面波导上实现光阻断效应。结果表明该复合平面波导具有良好的传输特性,可应用于制备光开关等波导器件,具有一定的应用潜力。     

最新发明专利信息

远距离读表装置该仪表读取装置具有一个由一对光纤构成的光纤传输通路,并连接在所要读取的仪表和仪表接口单元之间。光通过一根光纤传输到仪表的指示组件,而反射光通过第二光纤传输到接口单元中的传感器处。测量光纤光谱透射率的装置该装置包括一个积分球,该积分球具有分别用来连接光纤样品的光接收端和光出射端的两个开孔,与上述两开孔之一相对置设置一个光接收开孔,以及不与该两开孔相对置的另一个光接收开孔。来自诸如分     

光敏传感器的应用系统 （三）

五、光检测控制系统 1.光检测控制系统实例 光的应用技术可概括成四方面,即即光检测控制、光信息处理、信息传输和光能量应用。这里简述已实用的和正在开发的光检测控制系统实例。     

通信系统中光信噪比和偏振模色散的同时监测

提出了一种用偏振扰频和偏振光分束相结合实现光信噪比和偏振模色散同时监测的简便方法,通过测量两正交偏振测量臂中的偏振信号的光功率和消偏的背景噪声得到光信噪比(OSNR)和偏振模色散(PMD).监测得到的OSNR和PMD是相互独立的,从而使得网络操作者能够区分传输链路中光噪声和偏振模色散的影响.对20 Gb/s的传输链路的实验表明,OSNR的变化范围在18～36dB,PMD值的变化范围为0～73ps.     

基于光纤传输的数字音视频监控系统

介绍了一种基于光纤传输的四路数字音视频监控系统方案.该系统采用时分复用技术,利用大规模专用集成电路、可编程逻辑器件CPLD以及光收发一体化模块,使设计的光纤传输系统在一根光纤中实现四路音视频和反向控制数据的传输.     

A Surface Area Calculation and CAPP System for Non-Axisymmetric Deep Drawing Products

In this paper a surface area calculation for non-axisymmetric deep drawing products of elliptical shape was constructed for the design of blank shapes of deep drawing products by using an AutoLISP function in AutoCAD software. A computer-aided process planning (CAPP) system for rotationally symmetric deep drawing products has been developed. In this study, a CAPP system for non-axisymmetric deep drawing products of elliptical shape was constructed using process sequence design. The system developed consists of four modules. The first is the recognition of shape module for recognising non-axisymmetric products. The second is a 3D modelling module for calculating the surface area for non-axisymmetric products. The third is a blank design module for creating an oval-shaped blank with an identical surface area. The fourth is a process planning module based on production rules that play the most important role in an expert system for manufacturing. The production rules are generated and upgraded by interviewing field engineers. The drawing coefficient, the punch and die radii for elliptical shape products are considered as the main design parameters. The suitability of this system was verified by applying it to a real deep drawing product. This surface area calculation and CAPP system should be very useful for reducing the lead-time for manufacturing and for improving the accuracy of products.     

一种嵌入式远程监测与诊断系统及其应用

介绍一种嵌入式远程监测与诊断系统的软、硬件结构与功能,该系统前端采用嵌入式采集模块,适用于十分恶劣的现场环境下的设备运行状态监测.系统针对性强、安装方便、开发成本低,客户端采用B/S模式,升级与访问方便.系统可将模拟信号转化成数字信号进行远程传输,有效地解决了信号在传输过程中的损耗问题.     

毛细管气相色谱法测定塑料包装及其内食品中酞酸酯

建立了用毛细管气相色谱-氢火焰离子化检测器测定塑料食品袋及袋内包装食品中5种酞酸酯（邻苯二甲酸二甲酯（DMP）、邻苯二甲酸二乙酯（DEP）、邻苯二甲酸二丁酯（DBP）、邻苯二甲酸二正辛酯（DOP）和邻苯二甲酸二（2-乙基己基）酯（DEHP））的方法。样品用无水乙醇超声提取，经干燥脱水过0．45μm滤膜过滤，直接注入气相色谱仪进行分析。用保留时间定性，外标法定量。5种酞酸酯的回收率为71．5％～125．5％；精密度（RSD）为1．6％～3．2％；DMP、DEP、DBP、DOP和DEHP的检测限分别为0．18ng、0．13ng，0．13 ng、0．15ng和0．14 ng。该方法准确度和灵敏度高，样品用量少，前处理简单，可同时测定塑料食品袋及包装内食品中5种酞酸酯。     

Effect of Axially Grooved Oil Seals on the Leakage Flow and Stability of a Centrifugal Compressor

The results of an analytical investigation are given for the effect of axially grooved floating oil ring seals on the leakage flow and stability of a centrifugal gas compressor. The finite element method was used to solve the non-linear and coupled hydrodynamic and thermal equations for pressure and temperature distributions in the oil seal ring with and without the axial grooves. The peturbation technique was used to obtain the static and dynamic characteristics of the oil seal. The results for selected cases of axial grooving are presented in graphical form for operation at various eccentricities. The non-dimensional leakage flow results correlate well with previously published results calculated by narrow groove theory. The stability of a multi-stage gas compressor is evaluated for different configurations of the oil seal grooving geometry. The compressor rotor shaft finite element model includes a multi-level analysis for the oil seal rings that permits the evaluation of the floating seal influence on the total system stability. Results are given for both low and high-pressure sealing conditions, which simulate test stand and field operating conditions. The results show that the added grooves enhance the stable operation of the rotor system for low-pressure fixed seal conditions arid reduce the system stability at lower eccentricities for low-pressure floating seal conditions. In high pressure conditions the added grooves enhance the stability of the system for both fixed and floating seal conditions.     

并联柱塞泵水射流系统的研制和工程应用

水射流雾化制粉工艺和冷态钢材的磨料水射流除除鳞除锈工艺是典型的并联水射流系统工程应用,系统的流量脉动直接影响系统的工艺应用。本文介绍了上述2种典型并联水射流系统的研制,分析总结了泵的相位偏角差值对并联柱塞泵水射流系统流量脉动影响,认为泵之间存在最佳相位偏角使并联柱塞泵水射流系统的流量脉动率得到降低。     

Analysis of a crack approaching a circular hole in cross-ply laminates under biaxial loading

The problem of a crack approaching a circular hole in cross-ply laminates under uniaxial and biaxial loading is investigated in this paper. The effects of material orthotropy, geometry [R/d and a/d], and loading conditions on crack tip singularity are investigated. The stress intensity factors are obtained by the modified mapping collocation method. The present results for an isotropic infinite plate show good agreement with existing solutions. The results for cross-ply laminates show that the stress intensity factors strongly depend on material orthotropy, geometry, and loading condition. The stress intensity factors for cross-ply laminates exist between those for θ=0° and those for θ=90° in the whole range of crack length and decrease as the percentage of 0° plies increases. In the range of small crack length the stress intensity factors for biaxial tension are higher than those for uniaxial tension. In the range of large crack length the stress intensity factors for uniaxial tension are higher than those for biaxial tension.     

并联轴直线运动直线度的检测与误差补偿

通过采用Renishaw激光干涉仪检测混联机床并联轴直线运动的直线度误差,对直线度的干涉测量原理和方法进行深入探讨,提出一种并联轴直线运动直线度的干涉测量方法和误差补偿模型的建模方法。分析干涉仪直线度评定方法和算法,做出并联轴直线运动直线度双向平均偏差特性曲线,建立直线度误差数学模型。利用最小二乘法拟合得到直线度均值误差补偿模型。对并联轴直线运动直线度进行补偿,达到了提高混联机床几何精度的目的。     

HKD型航空润滑油本构方程的确定及拖动力计算

测量了HKD型航空润滑油的拖动力,确定了该油的本构方程,给出了本构方程中各种流变参数的计算方法并拟合出了计算公式,给出了拖动力的计算方法。结果表明:该油在试验条件下表现为粘弹性;拖动力的理论预测值与试验测量值之间误差较小,曲线形状一致,本构方程正确合理;流变参数的拟合公式精度较高。     

某无人直升机主传动齿轮啮合强度分析

基于ANSYS分析软件,采用接触单元,对某无人直升机主传动齿轮副的啮合过程进行数值模拟,直观得到了啮合过程中齿轮副上的瞬态应力,并对该齿轮副进行疲劳计算,预估其寿命,从而为该齿轮安全工作和优化设计提供理论依据。这种基于ANSYS的齿轮啮合强度分析方法可为其它齿轮啮合疲劳传动分析提供借鉴。     

最小包容区域法评定平面度误差的程序设计

介绍了最小包容区域法评定平面度误差的JAVA程序设计。采用三角形准则、交叉准则和直线准则分别求取最小包容区域,从三者中选取最小值作为平面度误差。得到的误差值具有唯一性。对数据采集的准备工作无特别要求,操作较简便。适用于三坐标测量机及其它仪器对平面度检测时数据的处理。