政策协调、不确定性与大型技术系统创新——中国核电技术赶超的案例研究

后发国家技术赶超需要实现“市场规模”和“技术自主”的双重目标,但现实中这一进程普遍面临技术依赖的“追赶者陷阱”的问题。论文采用个案内过程追踪的研究方法和“政策子系统”的分析视角,基于中国核电50年的技术赶超历程,解释了后发国家如何通过政策协调实现大型技术系统的技术赶超。研究发现,大型技术系统的创新绩效与其所在政策子系统的特性密切相关,核电政策子系统具有碎片化的结构和行为目标,需要同步进行政府部门间协调和政府对市场协调,协调机制主要包括国家意志、行政指令、共识信号和市场竞争等。政策协调通过降低大型技术系统中产业主体面临的供需不确定性,解决产业主体专用化投资不足的激励困境。跳出“追赶者陷阱”的关键在于建立国产化率目标硬约束与多种协调机制。研究进一步深化了对技术赶超中政府角色的认识,弥补了已有文献对于大型技术系统产业管理体制研究不足的理论缺口,对新型举国体制下提高系统创新能力有一定的启示。

低惯量交流系统并网变流器次/超同步振荡分析

低惯量电力系统中跟网型变流器可能会与同步机转子动态产生交互,给系统稳定性分析引入新的问题,仅靠跟网型设备动态和短路比衡量交流系统强度不再准确。为此,该文综合分析系统惯量和短路比对跟网型变流器小干扰同步稳定的影响,提出适用于分析低惯量系统中并网变流器稳定性的方法,所提方法计算量低、物理意义明确。首先,推导变流器和同步机混联系统的闭环模型,并提取出能表征低惯量动态的相互作用系数矩阵,定性分析两类设备间的交互关系。其次,基于模态摄动理论,将原多机系统解耦为稳定性等效的子系统。然后,选取适用于分析小干扰同步稳定问题的相位主导回路,根据该回路提出综合考虑惯量和短路比的稳定性分析方法。最后,基于仿真算例验证了所提低惯量系统中并网变流器小干扰同步稳定性分析方法的有效性。

基于EMD的密相气力输送两相流系统内子系统相互联系和作用

利用信号分析考察密相气力输送两相流系统内子系统之间的相互联系和作用。首先,基于经验模态分解(empirical mode decomposition,EMD)将密相气力输送两相流系统的静电波动信号分解成若干信号分量,即固有模态函数(intrinsic mode function,IMF),再结合各IMF分量的能量比重确定出IMF1~IMF4为主干分量。之后,结合静电信号EMD分解结果、输送管道中颗粒的分布状况及颗粒运动机理的差异性三者,明确气固两相流系统内的子系统。最后,利用IMF1~IMF4的主频和方差的变化规律,分别考察了子系统之间的联系和作用。实验结果表明:水平输送管道中的气固两相流系统可分成4个子系统,分别是稀相区、交界区、浓相区以及贴壁区内的颗粒流体组织;子系统之间依靠颗粒在彼此间游走而进行联系;同时,子系统之间也存在竞争作用,该竞争是颗粒主导和气流主导两种机制之间的竞争,当颗粒悬浮性较弱时竞争激烈,当颗粒悬浮性变好时竞争减弱。

导航卫星载荷分系统健康评估方法设计

面向下一代导航系统结合高中低轨构建导航星座的设想,随着遥测参数数量和种类的激增,针对传统健康评估方法面临的过往专家知识难以适用、故障机理储备难以覆盖全面的问题,提出了基于局部异常因子检测-贝叶斯网络结构学习的导航卫星载荷分系统健康评估方法;通过采集某卫星系统实际故障时间点前后数据,设计实验验证了局部异常因子检测方法能够以粗粒度正确输出单机级的健康状况;分析比较了3种评分函数下,贝叶斯结构学习的效率和模型的准确度;实验结果表明,当评分函数分别选为BDeuScore、K2Score以及BicScore时,学习到的模型对系统的健康评估准确度分别为87.4%、80.5%和85.2%;总结了局部异常因子检测-贝叶斯网络结构学习方法各自的不足,为导航卫星分系统健康评估方法提供了新方向和思路。

基于模型的民机运营阶段失效评估方法研究

基于模型的安全性分析(model-based safety analysis,简称MBSA)方法自提出至今,已经日益成熟,更适用于复杂的民机系统。在当前研究和ARP4761A草案的基础上,运用MBSA方法开展民机在运营阶段的失效评估方法研究,其相较传统方法,将运营数据、功能失效和设备故障集合进同一个模型中,更便于开展运行失效评估。首先,定义运行失效评估模型基本元素,梳理模型构建流程,基于Simulink建立包含失效模块的设备级、系统级和飞机级模型。之后,选择某型号飞机外部照明子系统构建模型,利用某机队运营阶段的运行数据开展算例分析。结果表明,基于模型的失效评估与故障树计算结果误差在可接受范围内,同时开展失效模式与影响分析(failure mode and effect analysis,简称FMEA),利用运行数据计算和仿真得到丧失着陆照明功能危险的发生概率,30次仿真结果表明基于运行数据的发生概率在设计值附近波动,整体略大于设计值,但仍满足安全性要求。

玉米收获机的控制系统优化设计

针对4YZL-9型玉米收获机,设计了一款控制系统,并以PLC控制器为核心,分别设计了驱动行走子系统、割台液压子系统及脱粒清选液压子系统。主要的控制过程为:利用湿度传感器采集玉米籽粒含水量,利用压力传感器采集检测玉米喂入量,利用霍尔传感器检测收获机各种速度信息,利用位移传感器检测玉米的距离,并将这些数据发送给PLC控制器,经过计算,输出驱动命令,通过电磁换向阀和电磁比例阀调节控制收获机的割台高度、行走速度、脱粒滚动转速、风机转速及清选筛箱转速等,使得玉米收获机高效的完成行走、收割、脱粒、清选等一系列的收获作业。试验结果表明:加装了控制系统的4YZL-9型玉米收获机正确采摘率为96.7%,玉米粒损失率≤2.4%,籽粒破损率≤3.6%,收获机故障率≤5%,含杂率≤2.8%,能够准确高效地完成玉米的收获作业。

匈塞铁路贝旧段基础设施子系统TSI认证实践

随着“一带一路”倡议实施,中国铁路“走出去”步伐不断加快。为保证我国铁路企业参与建设的匈塞铁路贝旧段项目顺利进行,需全面解读欧盟铁路互联互通技术规范(TSI)认证要求,包括通用、特定基本要求。铁路基础设施子系统TSI认证包括互通性(IC)部件认证、EC符合性验证、项目竣工认证3个部分,主要流程为:制定认证计划—准备认证申请—提交认证申请—技术评估—证据收集和分析—发布认证结果—认证后监督。通过匈塞铁路贝旧段基础设施子系统TSI认证实践,梳理了基础设施子系统的认证内容、流程和要点,可为我国铁路技术规范和合格评定体系完善提供参考,也可为我国铁路在国际市场的竞争提供有力支撑。

数控机床能耗子系统的分析与数学建模

从数控机床能耗子系统的角度,将数控机床分为加工动力能耗子系统、数控能耗子系统、电气能耗子系统、机床辅助能耗子系统等4个能耗子系统.根据数控机床各个能耗子系统的能量分布,分离出子系统的能耗方程并建立数学模型,通过分析各个能耗子系统的运行特点,建立数控机床能耗模型.该能耗模型使得数控机床能耗分布的参数变量获取更加简洁方便,同时对机床和工况变化的适应性更强.实验结果表明,本文所建立的能耗模型适用于数控机床在待机、准备、空载以及加工等各种运行阶段的能效分析,为数控机床能效优化设计及节能技术提供基础支持,具有良好的应用前景.

某三级医院电气智慧设计的应用探索

结合某三级医院的设计案例,根据医院建筑的功能和使用要求,阐述在智慧系统设计方面的应用场景,详细介绍智慧变电所管理系统、智慧UPS监控系统、高效机房系统及智能预警电缆系统等子系统的架构及作用。

船舶甲板抛丸机器人系统设计

针对目前抛丸装置操纵控制不便、智能化程度低等问题,设计一种船舶甲板抛丸机器人系统。论述该系统的结构组成、控制系统、软件设计和激光导引规划工作流程,并在实船甲板上进行试验。试验结果表明,该系统可实现对抛丸、除尘和移动等作业环节的控制,并具备一定的自主导引抛丸作业功能。

基于软件中间件的多类型视频编码板兼容性设计

针对机车车载安全防护系统机车自动视频监控及记录子系统(简称“6A视频子系统”)的设计、构建和维护过程中多种类型编码板兼容的问题,文章提出了一种利用软件中间件屏蔽底层软、硬件差异的设计方案,其从板卡识别、视频码流获取、关系解耦、差异注册和动态库加载等方面分析研究,设计了一个独立的软件中间件,实现了多种类型视频编码板的兼容。验证及应用结果表明,所提方案解决了在不重启视频系统的情况下不同类型视频编码板的动态替换和兼容性问题,从而提升了6A视频子系统批量应用和维护过程中的检修作业效率,单台车故障处理时间降低至原来的三分之一。多种类型视频编码板产品的便捷互换,可避免6A视频子系统的成套更换,从而大幅降低系统的检修成本。

涡北煤矿地面集中式降温控制系统设计与应用

针对涡北煤矿降温项目设计一套集“管”“控”为一体的集中控制系统,重点分析了该系统的网络架构、硬件组成及软件应用,详细描述了该系统实现的主要功能。提出基于BP神经网络PID控制算法对系统优化,以实现二次冷量的精准分配,达到节能减排的效果。在人机交互界面中引入3D建模技术,为矿方提供更加简洁、功能齐全、友好的人机交互界面,通过通信技术将整个降温系统的子系统全部纳入集中监控系统,提高了降温系统的生产效率,达到减员增效的效果,并预留与矿井调度通信接口,为矿井综合自动化系统提供相关基础数据。

汽车行业电气开发管理流程

随着汽车电动化、网联化、智能化、共享化的普及,电器架构、功能和子系统、控制器经过几轮迭代开发,电子电气架构及基础技术开发方法论已经基本形成,因此对当前的工作流程、方法论等进行梳理总结,保障功能软件开发模块在项目开展过程中的活动顺利开展,并满足关联部门交互指导及交付要求,进而提升功能软件设计质量,满足客户需求,使客户达到满意的目的。

交直流电网实时协调安全控制技术设计与实现

针对交直流混联送端电网依然存在着暂态稳定、弱阻尼振荡和频率稳定等运行风险,提出了交直流电网实时协调安全控制技术。根据送端电网受扰后不同阶段的特点,交直流电网实时协调安全控制技术充分发挥电力电子装置的控制性能,对暂态稳定、频率稳定和动态稳定等多种稳定过程协调优化并进行附加控制。以许继的HCM3000软硬件平台为稳控执行单元开展交直流电网实时协调安全附加控制技术研究,实现控制策略的在线优化,并在实验室条件下验证了交直流电网实时协调安全控制策略的有效性。

Design on the Soccer-robot Wireless Communication Subsystem

在足球机器人比赛中，无线通信子系统的主要任务是将主机的命令准确地传送给每一个机器人，其性能的好坏，将会影响足球机器人的运动和比赛的顺利进行，直接关系到比赛的胜负。本文提出了一种基于高速尢线通信模块PTR6000的设计方案，介绍了发射和接收部分的硬件及软件设计，有效地提高了通信系统的性能，为足球机器人系统提供了一个高效可靠的通信平台。

Useful life prediction using a stochastic hybrid automata model for an ACS multi-gyro subsystem

A useful life prediction method based on the integration of the stochastic hybrid automata(SHA) model and the frame of the dynamic fault tree(DFT) is proposed. The SHA model can incorporate the orbit environment, work modes, system configuration, dynamic probabilities and degeneration of components,as well as spacecraft dynamics and kinematics. By introducing the frame of DFT, the system is classified into several layers, and the problem of state combination explosion is artfully overcome.An improved dynamic reliability model(DRM) based on the Nelson hypothesis is investigated to improve the defect of cumulative failure probability(CFP), which is used to address the failure probability of components in the SHA model. The simulation using the Monte-Carlo method is finally conducted on two satellites, which are deployed with the same multi-gyro subsystem but run on different orbits. The results show that the predicted useful life of the attitude control system(ACS) with consideration of abrupt failure,degradation, and running environment is quite different between the two satellites.

Kinematics Analysis of Motion Simulation Subsystem for Unmanned Vehicle

Unmanned vehicle has attracted wide attention and interests throughout the world since it first deputed in the 1960s. However, the experimental methods for unmanned vehicle＇s intelligent behavior, such as semi-physical simulation and motion subsystem, have not been widely explored. First, the requirements of the motion subsystem in unmanned vehicle semi-physical facility are analyzed, and a six DOF parallel manipulator is selected to reproduce the pose of the vehicle. The link lengths of the motion subsystem are worked out under the given rotational angles of the vehicle. According to the geometric properties of tetrahedron, three joint positions of the top platform are determined, and the rest are obtained from the first three position vectors. Six constraint equations are set up based on the vertices on the top platform and the link lengths. In order to solve the six angle variables, a numerical algorithm built on the Newton-Raphson iterative method is presented, which is based on Taylor series expansion of six constraint equations. The pose of the top platform is ultimately calculated. The eigenvalues of the top platform are solved to obtain the natural frequencies of the motion subsystem. The coordinates of six joint centers on the top platform and six constraint equations can be realized by simple algebraic manipulation, which allows significant abbreviation in the formulation and provides a systematic way of obtaining the kinematic solution of the parallel manipulator. A numerical example is given and its efficacy is demonstrated by the inverse kinematics. The computation strategy based on tetrahedron method and Newton-Raphson iterative method provide a simple and cost-effective method for solving forward kinematics of six DOF parallel manipulators, and this method sheds light on other parallel manipulators.

A smartcard conditional access interface scheme for conditional access subsystem separation in digital TV broadcasting

Conditional access system (CAS) is a key technical component in digital TV broadcasting through which TV op-erators manage the appropriate rights of different subscribers in order to protect their commercial benefits. The normal digital TV receiver can only receive and decode the pay TV programs scrambled by one specific CAS. In this paper, the authors proposed a smartcard conditional access interface (SCAI) scheme in order to make the digital TV receiver be a common receiving platform independent of any specific CAS employed at the broadcasting head-end. As a result, it only needs to include a common condi-tional access software package (CCAP) without any requirement of hardware modification in the receiver. Comparison between the two mentioned DVB-CI-based schemes showed that the cost of such kind receiver is greatly reduced. The main design points of the proposed scheme and its reference implementation’s architecture are presented in this paper. This scheme is also one of the candidate national standards for Chinese digital TV broadcasting industry.

The Design of I/O Subsystem in Satellite Real-Time Microkernel Operating System

One of the most important features of modern minor satellites is to realize autonomous moving. The performance of the satellite autonomous computer operating system acting as the control center is utmost important. The recent trend in operating system development is adopting microkernel architecture which holds such advantages as microminiaturization, modularity, portability and extendibility. The performance of I/O subsystem is currently receiving considerable research attention. Object-orientation offers an approach to application development in which software system can be constructed by composing and refining the pre-designed plug-compatible software components.It also starts with some basic notions fairly well accepted in computer science, namely encapsulation and reuse. In this paper, a new object-oriented real-time I/O subsystem model has been designed.In this model, the traditional I/O subsystem framework is discarded and a stream mechanism based on the object-oriented concept is introduced. In addition, the I/O requests are classified according to their time emergency to obtain real-time performance. So, this model meets such satelliteperformance requirements as reliability, flexibility, portability and real-time performance.

Prototype for Integrating Internet of Things and Emergency Service in an IP Multimedia Subsystem for Wireless Body Area Networks

In recent years, the application of the Internet of Things （IoT） has become an emerging business. The most important concept of next-generation network for providing a common global IT platform is combining seamless networks and networked things, objects or sensors. Also, wireless body area networks （WBANs） are becoming mature with the widespread usage of the IoT. In order to support WBAN, the platform, scenario and emergency service are necessary due to the sensors in WBAN being related to wearer＆#39;s life. The sensors on the body detect a lot of information about bioinformatics and medical signals, such as heartbeat and blood. Thus, the integration of IoT and network communication in daily life is important. However, there is not only a lack of common fabric for integrating IoT with current Internet and but also no emergency call process in the current network communication envi-ronment. To overcome such situations, the prototype of integrating IoT and emergency call process is discussed. A simulated boot-strap platform to provide the discussion of open challenges and solutions for deploying IoT in Internet and the emergency commu-nication system are analyzed by using a service of 3GPP IP multimedia subsystem. Finally, the prototype for supporting WBAN with emergence service is also addressed and the performance results are useful to service providers and network operators that they can estimate their migration to IoT by referring to this experience and experiment results. Furthermore, the queuing model used to achieve the performance of emergency service in IMS and the delay time of the proposed model is analyzed.