基于Arduino Uno R3的蓝牙操控机械臂设计

为行动不便的人群提供各种服务的机器人正在成为一种迫切的社会需求.基于以上思路,可设想出具有抓取性能的电子设备可实现此功能,故构想出机械臂.为提升该系统的性能通过对软件及硬件架构进行深层次分析,提出了一种控制系统架构的设计方法如下--该机械臂以Arduino Uno R3为控制核心,利用蓝牙进行操控,舵机使之运动.如此可...     

一种减少锌渣生成的镀锌添加剂

钢丝热镀锌过程中易产生大量锌渣。为降低锌损耗,研制了一种镀锌添加剂。该添加剂可抑制亚铁离子的产生,从而减少锌渣的生成     

垂直腔表面发射激光器的研究

垂直腔表面发射激光器(VCSEL)是一种应用于光纤通信系统的低成本、高性能的特定波长光源,它具有测试简单、易耦舍以及易形成阵列等独特优势,已在光并行互连及高密度光存贮等领域得到大规模应用.文章介绍了VCSEL的结构和当前的制造工艺水平,阐述了各波段VCSEL的发展和应用现状,探讨了VCSEL在不同领域中的应用范围并指出了VCSEL的发展前景.     

丙类谐振功率放大器动态线作法与应用探讨

基于晶体三极管在共射组态的大电流和大集－射电压的电特性,提出了适于丙类谐振功率放大器动态线的近似作法,讨论了各有电压和负载的变化对动态线的影响,并运用该动态线对丙类谐振功率放大器的工作状态和性能进行了定性分析。     

Power consumption analysis of video streaming in 4G LTE networks

Video streaming, one of the most popular technologies for online video playback, has already been applied to 4G LTE networks. Previous work has been devoted to understanding the power consumption in general 4G LTE networks, while it is still unclear how the online video streaming makes impact on the power performance of mobile devices. Inspired by this, this paper investigates the relationship between the mobile device’s power performance characteristics and the behaviours of video streaming in 4G LTE networks. There are many natural issues/questions that are clearly interesting and important, while it is non-trivial to answer these issues/questions exactly (e.g., where is the energy saving room? how much is it?). To address a series of issues like the above, we formulate our energy models together with an algorithm that can assist our analysis. Particularly, we design a systematic platform, and conduct a comprehensive and also deep analysis on the power consumption of video streaming in 4G LTE networks. Our experiments reveal us a series of valuable findings—the saving room in the network part is large (from 41.86 to 69.62%), the number of RRC tails and the transmission pattern could be promising for optimizing the power consumption, for example.     

Multi-domain architecture for policy management inumts ip multimedia subsystem

The Universal Mobile Telecommunications System (UMTS) offers IP-based multimedia applications and services with end-to-end Quality of Service (QoS) guarantee. The key component providing these services is the IP Multimedia Subsystem (IMS) that uses Service-Based Local Policy (SBLP) management for QoS control. To support end-to-end QoS, the UMTS IMS network should be scalable, reliable and flexible in policy deployment and enforcement, characteristics that are not found in single-domain policy architecture. A hybrid policy architecture is proposed, in which a hierarchical architecture is applied to the multi-domain environment in a single operator UMTS IMS network, while a peering architecture is employed in a multi-operator UMTS IMS network. The proposed multi-domain policy architecture potentially minimizes the session setup delay and policy exchange traffic while maximizing network scalability.     

Microstructure transformations induced by modified-layers on pentacene polymorphic films and their effect on performance of organic thin-film transistor

Phenyltrimethoxysilane was used to modify SiO₂ insulator and significantly enhanced the pentacene based organic thin-film transistors (OTFTs). The crystal structure, surface morphology, molecular structure and microstructure of pentacene polymorphic films with and without the modifications were investigated using X-ray diffraction (XRD), atomic force microscopy (AFM) and contact angle meter. XRD studies reveal a decreased tilt angle (θ_T) of pentacene molecules from c-axis toward a-axis, indicating that polymorphs transformation from the “triclinic bulk” phase to the “thin film” phase and orthorhombic phase occurs. AFM images show that the surface roughness of gate insulators has no influence on performance of the pentacene based OTFT. These results provide strong evidence that the performance improvement of OTFT after PhTMS modification of SiO₂ insulator surface is related to the microstructure transformation of the semiconductor. It suggests that the modified-layer may alter the molecular geometry and further induce structural phase transitions in the pentacene films for the performance improvement.     

一种新型的寻呼网络——虚拟寻呼网

随着无线寻呼的发展 ,寻呼联网成为寻呼业发展热点之一。本文介绍了一种新型寻呼网络—虚拟寻呼网 ,它组建、管理及扩容都很简便 ,同时建网成本低     

模拟燃气射流场的莫尔偏折显示及定量测试

在实验室条件下,制作了模拟膛口高速射流的装置.应用莫尔偏折法对双基发射药膛口燃气射流场进行了显示及定量测试研究.整套莫尔显示及测试系统由激光光源、莫尔偏折仪、CCD、监视器、图像存储和处理系统以及586计算机等组成.应用莫尔偏折层析技术定量计算并再现了膛口双基发射药燃气射流场的温度分布.     

10J／0.4ms重复脉冲Nd：YAG激光器

报道了一种频率为１、５、１０和２０ＨＺ,单脉冲能量超过１０Ｊ,脉冲宽度小于０．４ｍｓ,能量外流地４％的重复脉冲Ｎｄ：ＹＡＧ激光器。