大数据环境下MapReduce准入控制的设计与实现

为了保证Hadoop平台的安全性,确保执行MapReduce作业的TaskTracker节点符合Hadoop平台的安全管理要求,杜绝非法用户对TaskTracker节点访问并对其分配任务,提出了一种对JobTracker节点进行身份认证的方法,设计实现了对JobTracker节点进行身份认证的认证体系。该认证体系主要是基于802.1x进行准入控制,重点分析了MapReduce分布式计算的流程,提出了总体设计方案,完成了相关模块的配置实现,最终结果显示只有通过认证的JobTracker才能通过交换机的可控端口给相应的TaskTracker节点分配任务,有效地避免了非法用户的访问,增强了Hadoop平台的安全性、可靠性,为建设安全的大数据环境提供了很好的技术支持。     

基于PXI Express总线的多通道数字化仪软件技术研究

针对各种数字化设备高采样率和高分辨率的测试需求,设计一种基于PXI Express总线的多通道数字化仪。该数字化仪开放性高,灵活性好,模块化强,广泛应用于测控领域中。结合数字化仪开发过程中所面临的关键问题及解决方案,重点从设备驱动程序、接口封装和应用软件三个方面进行分析阐述。首先,深入研究了KMDF设备驱动开发过程中几个关键问题,如配置空间访问、中断处理、DMA数据传输等的运行机制及实现方法;然后,以数字化仪应用需求为背景,阐述了采用.Net平台下三层体系架构的软件总体设计;最后,大量实验测试和结果分析表明,该数字化仪具有较强的可靠性和稳定性,达到预期技术要求和性能指标。     

调度自动化机房网络配线管理软件设计与实现

针对公司调度自动化机房网络配线无图纸管理和标签标识不规范的情况,自主研发了一套机房网络配线管理软件。首先,分析了配线可视化管理软件应对网络配线绘图和标签信息自动生成的功能需求,并运用MVC模式理论进行软件架构设计;其次,重点阐述了基于QT图形库的关键功能实现,包括核心图元类的构建、元件库组件可配置生成、图形序列化反序列操作、拓扑查找、设备图元属性管理及标签信息自动生成功能等;最后,通过举例说明该软件在实际机房管理中的使用方法和应用成效。应用结果表明,通过绘制整个机房的网络连接图并录入相关设备属性信息,有助于提高机房网络故障的诊断效率和降低机房系统的运维风险。     

基于CP-ABE的云计算改进属性加密安全访问控制策略设计

针对云计算存储中心由于数据和访问控制的安全性无法得到有效保障,从而可能造成用户存储的敏感数据被盗取的问题,现有的解决方法往往通过加密数据密钥,并通过对数据加密来解决安全性问题,但这些方法没有对访问控制的整个过程进行全面的定义和描述,同时仍然具有较大的时空开销。为此,在对CP-ABE(eiphertext-policy attribute-based encryption)进行深入分析的基础上提出了一种基于改进属性加密访问控制模型,然后对CP-ABE进行改进,并对公钥和主密钥的生成、数据所有者加密文件、访问用户解密文件以及用户权限的全面管理过程均进行了详尽的定义和描述,从而设计了一种通用的安全访问机制。在仿真工具Ubuntu中进行实验,结果表明文中方法能有效地实现云计算环境下的安全访问控制,与其它方法相比,具有计算和存储开销低优点,具有较大的优越性。     

基于列车智能显示器故障记录处理的设计与研究

列车在外部环境的影响下导致各设备的软硬件产生缺陷从而引发故障,在一定程度上影响了列车的性能和安全。显示器是列车必不可少的重要部件,是人机交互的桥梁,也是列车各设备故障状态信息显示的窗口。针对传统列车显示器的故障误报和易产生故障空白记录的现象,文章设计和实现了基于故障码的列车显示器故障信息搜索和分析方法,大大提高了列车显示器应用设计人员的开发效率,减少了故障记录过程的工作量。并基于实际测试环境对该方法进行了实验,结果表明,该方法对列车显示器故障记录的处理具有高效性、健壮性,并保证了显示器故障信息显示的准确性。     

WebGIS中带图业务数据的缓存和预取机制研究

目前在WebGIS中地图缓存已得到深入的关注和研究,随着WebGIS客户端性能的逐渐增强,如图片音频等越来越丰富的内容也能被展示出来。由于服务端磁盘读取和网络传输两大瓶颈,一定程度上延长了用户访问这些资源的等待时间。以某高速公路管理系统为背景系统,采用了在服务端和客户端各加一组业务数据缓存、客户端启动后预先读取服务端缓存的方式,提高了带图片的业务数据的访问性能。同时根据该WebGIS中业务数据特有的地理位置关系,在分析用户访问轨迹后,客户端预测用户可能访问的下一条数据并预取,进一步提高了缓存性能。     

基于PXI总线的Φ0.5米高超声速风洞测量系统研制与应用

测量系统是风洞中必不可少的重要的设备之一,其性能对风洞试验的准确性、可靠性和运行效率具有至关重要的影响。近年来,Ф0.5米高超声速风洞原有测量系统逐渐暴露出精准度下降、软件通用性不足、维护不便等缺点,已不能完全满足日益复杂的风洞试验需求。针对此情况,该风洞重新研制建立了一套基于PXI总线的64通道的测量系统,并通过严格测试投入应用,该系统的应用在一定程度上提高了试验数据测量的准确性、可靠性和自动化程度,拓宽了Ф0.5米高超声速风洞的综合性能。     

无人机远程故障测试与诊断技术研究

为了确保众多无人机能够远程共享测试设备与技术人员等资源,设计了一种基于DataSocket技术和信息融合理论的远程故障测试与诊断系统;该系统采用PXI总线模块作为数据采集设备,利用DataSocket技术和虚拟仪器实现测试数据的远程传输;采用基于D-S证据理论的多智能诊断算法数据融合技术,提高故障诊断的准确率;同时为了便于故障信息的管理,把诊断出的结果存放在数据库中,远端使用B/S架构获取诊断数据;该远程故障测试与诊断系统可提高故障诊断正确率,实现故障信息的统一管理,节约成本提高效率,有一定的工程应用价值。     

航空成像设备自动调焦方法

随着航空技术的不断发展,航空成像设备不断涌现,对设备调焦精度要求也越来越高。提出一种航空成像设备自动调焦方法,重点分析自动调焦控制原理和光栅法调焦原理,同时给出自动调焦系统在整个航空成像设备中的工作流程,对光学系统允许离焦量进行计算及实验验证,并说明实际照相过程中如何进行自动调焦补偿。实验表明,通过该方法进行自动调焦,调焦精度优于0.02mm,调焦时间约5s。     

空空导弹测试系统应用LXI总线研究

首先对空空导弹测试系统应用各种仪器总线的情况进行了分析研究,然后介绍了一台PXI总线测试设备的改造方案,该方案中设计了一套基于LXI总线控制的电源子系统,该子系统与PXI主系统一起形成了新的混合总线控制测试设备。该改造方案实现了改造需求中的低成本和小型化设计。同时,结合该方案分析了LXI总线在空空导弹测试系统上应用的优缺点和现阶段局限性。提出了空空导弹测试系统应向着通用、开放和网络化方向发展的观点,得出了未来的空空导弹测试系统将是包含GPIB、VXI、PXI、LXI等总线接口的合成系统,各总线接口仅是网络上的一个节点的结论。     

基于虚拟仪器及PXI技术的传感器标定

为了借助虚拟仪器技术实现对叶轮机械各种测试技术的集成,本文将虚拟仪器及PXI技术运用于传感器的标定中。文中阐述了基于虚拟仪器及PXI技术的传感器静态特性标定系统的结构、标定方法、数据处理以及被标定传感器的静态特性指标,并与传统仪器组成的标定系统进行了比较。结果表明,基于虚拟仪器及PXI技术的传感器静态特性标定系统,比用其它手段更精确、快捷和方便,为虚拟仪器在叶轮机械试验测试中的进一步应用打下了基础。     

航电设备通用检测维护台的设计

为了适应机载武器装备系统的多样化以及通用性要求,搭建了基于PXI总线的航电设备通用检测维护台,在系统架构、硬件设计以及软件开发等各方面进行了通用性设计。该航电设备通用检测维护台基于PXI构架,挂装不同种类的适配器,操作通用平台上的人机接口,可满足多种设备的检测、测试任务。航电设备通用检测维护台在一个机柜内实现了人机交互操作,大功率、高精度、多种类通用电源及PXI智能测试平台等的高度集成。该通用平台具有良好的通用性和扩展性,适用多种机型、多种航电设备。通用平台已在某型航电设备的检测维护中完成了工程验证,系统性能稳定,适用性强,可实现多种航电设备的检测维护工作,也可推广至海军舰艇、兵器车载装备等。     

Multi-Party Quantum Key Agreement Protocol for Smart Home Environment

The most typical case of applying technology and communication technology to life may be the popular smart home series. Users can remotely control smart devices through mobile phones, which is convenient and fast, greatly changing people’s way of life. However, the safe login of smart devices has become a thorny problem. With the emergence of quantum computer, the common encryption method cannot prevent quantum attacks. In addition, a family often has multiple smart devices and multiple family members. Each user can log in to multiple smart devices, and each device can also be logged in by multiple users. Therefore, in view of the above situation, we propose a multi-party quantum session key agreement protocol based on Bell states and single particles, which can be used for multiple participants to negotiate session keys together, and improve the efficiency of users logging in and using smart devices. Moreover, our protocol ensures that each party has an equal opportunity to decide the final shared key, no party can determine the final key individually. Furthermore, security and efficiency analysis show that our protocol can achieve ideal results under the existing quantum technology.

     

Prioritizing the multi-criterial features based on comparative approaches for enhancing security of IoT devices

The Internet of Things (IoT) technologies continuously expand with time due to the advances in automated, connected device technology, mobility, and wide access to information. IoT is the collection of many linked devices due to their unique features, such as scalability, maintainability, fault tolerance, reliability, accuracy, and much more. With the growing number of hybrid devices in large organizations, security and privacy concerns are becoming more challenging. Security is essential for protecting the hardware, network aspects of devices, and information access from unauthorized entities. Most of the security methods and procedures provided by researchers are based on existing Internet security practices. The top-ranking authentication feature categories included the most compatible and common authentication feature for all types of IoT-based devices as an elementary security requirement for protection from unauthorized access. The future challenge is to address the incompatibility of the authentication feature with IoT devices based on appropriate technologies. AI and machine learning are also implementable in order to detect the vulnerability of IoT devices and inform the concerned operator or administration for protection. This research highlights the authentication feature of IoT devices from literature studies and evaluates the significant feature using COPRAS approach to assist organization in enhancing security of IoT devices.     

基于串口转WiFi的物联网终端远程控制实现方法

随着物联网技术的高速发展,对同一无线局域网内的设备进行控制时,存在传输距离短、可移动性差等缺点。针对此问题,提出了一种物联网终端远程控制的实现方法,采用串口转WiFi模块,通过Socket模式下的透传机制,传统的串口设备能够无线接入到互网络中基于MQTT消息传输协议的服务器上,完成数据的接收和发送,从而使终端设备突破无线通信距离的限制,达到数据交互和远程控制的目的。实验结果表明该方法正确、可靠,可广泛应用于智能家居、工业控制等领域。     

Electrooptical behaviour and control of a suspended particle device

A suspended particle device is made by electrophoretic rod-shape particles suspended in an organic gel. These particles can twist and order with an applied voltage. The light crossing the material suffers more or less scattering according to that voltage. A commercial device is analyzed in this work. Several electrical models are tested, being the best one a series configuration including a shunt double layer capacitance and a Warburg element. Main parameter errors are below 2%, showing the quality of this new electrical model for this kind of devices. A quick method to improve the manufacturing process on-line is also proposed. Impedance measurements will be fitted to the selected electrical model, in order to check physical aspects such as charge diffusion lengths and response times. An electronic driver to obtain several levels of device transmission has been also developed, being its linearity demonstrated too. Colour changes are negligible for the main part of the bleaching process. All these features allow the use of this set in domotics application.     

TMS320C5402与PC机串行通讯的实现

介绍了在串口工作模式下TMS320C5402的多通道缓冲串口(McBSP)与PC机实现串行通讯的方法，并给出相应的硬件配置、软件流程和应用实例。     

Time allocation improvement method for UAV-based wireless energy transfer cooperative mobile edge

Wireless power transfer (WPT) and mobile edge computing (MEC) are two advanced technologies that could improve the computing power and range of mobile devices. However, by integrating the unmanned aerial vehicle (UAV) into wireless powered MEC systems, wireless energy transfer will be susceptible to the “double near–far” effect. Therefore, in order to further overcome the influence of the “double near–far” effect, this paper considers the optimization of time slot allocation for UAV-assisted wireless powered cooperative MEC system, which includes an access point (UAV) and two mobile devices. The purpose of the study is to minimize the total transmission energy of the UAV while satisfying the delay and size of the computational tasks, so this paper proposed a 2:1:1 time-slot optimization allocation method. The method exploits the synergy of users so that the mobile device which is closer to the UAV acts as an offloading relay, by combining power and time slot optimization to minimize the total energy consumption of the UAV. Compared with the equal time slot scheme before the improvement, this method can not only utilize the wireless transmission energy to charge the mobile device for more time in the first period, but also can save the time of data transmission of the closer device in the third period, and it can enhance the rate of data transmission of the mobile devices at the same time. The results show that the task capacity of the system computed will be increased compared to the original scheme; the total transmission rate of the whole system is also improved by the same order of magnitude. The simulation results verify the effectiveness and reliability of the algorithm of the paper, and the comprehensive performance of the system can be maximized by the flexible offloading algorithm.