Software Development for Digital Control of WDW Series Testing Machine and Measurement of K_(IC)

Software has been developed for digital control of WDW series testing machine and the measurement of fracture toughness by modularized design. Development of the software makes use of multi-thread and serial communication techniques, which can accurately control the testing machine and measure the fracture toughness in real-time. Three-point bending specimens were used in the measurement. The software operates stably and reliably, expanding the function of WDW series testing machine.

Application study of digital PID controller in cockpit temperature auto-regulating system

Aiming at the inherent blemish existi ng currently in airplane cockpit temperature regulating system,a digital temperatu re auto-regulating design scheme of the system is put forward,namely,a digita l proportional-integral-derivative(PID) controller used for temperature contr ol is designed.And then it is applied in airpl ane cockpit temperature regulating system by adopting the way of cascade control.Experiment results indicate that the design scheme is reasonable and practical.

Comparative Analysis of Analog and Digital Controllers for Negative Output Superlift Luo Converter (NOSLC)

This paper focuses on the comparative study of analog and digital control techniques for Negative Output Superlift Luo converter (NOSLC). NOSLC is a high gain converter in which the positive source voltage is converted into a negative load voltage. Though the negative load voltage is produced effectively, there is lot of non-linearities that affects the voltage level. To overcome this, analog controllers like Proportional-integral (PI), fuzzy PI and a sliding mode controller (SMC) were proposed for NOSLC. However PI controller does not respond to changes in operating point, fuzzy PI is based on the systematic approach and proved to be a trial and error oriented method and SMC brings an oscillation in the duty cycle. Therefore, to overcome these drawbacks, a digital control technique using PIC microcontroller is proposed in this paper which provides high versatility and programmability approach. Simulation studies are carried out in MATLAB and the performances of these controllers have been investigated for the proposed DC-DC converter. A prototype of the NOSLC converter is built by employing digital control and the results are verified experimentally.

PRECISE INTEGRATION METHOD FOR LQG OPTIMAL MEASUREMENT FEEDBACK CONTROL PROBLEM

By using the precise integration method, the numerical solution of linear quadratic Gaussian (LQG) optimal control problem was discussed. Based on the separation principle, the LQG central problem decomposes, or separates, into an optimal state-feedback control problem and an optimal state estimation problem. That is the off-line solution of two sets of Riccati differential equations and the on-line integration solution of the state vector from a set of time-variant differential equations. The present algorithms are not only appropriate to solve the two-point boundary-value problem and the corresponding Riccati differential equation, but also can be used to solve the estimated state from the time-variant differential equations. The high precision of precise integration is of advantage for the control and estimation. Numerical examples demonstrate the high precision and effectiveness of the algorithm.

Digital Servo Control of a Robotic Excavator

An electro-hydraulic control system is designed and implemented for a robotic excavator known as the Lancaster University Computerised and Intelligent Excavator （LUCIE）. The excavator is being developed to autonomously dig trenches without human intervention. Since the behavior of the excavator arm is dominated by the nonlinear dynamics of the hydraulic actuators and by the large and unpredictable external disturbances when digging, it is difficult to provide adequate accurate, quick and smooth movement under traditional control methodology, e.g., PI/PID, which is comparable with that of an average human operator. The data-based dynamic models are developed utilizing the simplified refined instrumental variable （SRIV） identification algorithm to precisely describe the nonlinear dynamical behaviour of the electro-hydraulic actuation system. Based on data-based model and proportional-integral-plus （PIP） methodology, which is a non-minimal state space method of control system design based on the true digital control （TDC） system design philosophy, a novel control system is introduced to drive the excavator arm accurately, quickly and smoothly along the desired path. The performance of simulation and field tests which drive the bucket along straight lines both demonstrate the feasibility and validity of the proposed control scheme.

BBACIMA:A Trustworthy Integrity Measurement Architecture through Behavior-Based TPM Access Control

Two limitations of current integrity measurement architectures are pointed out： （1） a reference value is required for every measured entity to verify the system states, as is impractical however; （2） malicious user can forge proof of inexistent system states. This paper proposes a trustworthy integrity measurement architecture, BBACIMA, through enforcing behavior-based access control for trusted platform module （TPM）. BBACIMA introduces a TPM reference monitor （TPMRM） to ensure the trustworthiness of integrity measurement. TPMRM enforces behavior-based access control for the TPM and is isolated from other entities which may be malicious. TPMRM is the only entity manipulating TPM directly and all PCR （platform configuration register） operation requests must pass through the security check of it so that only trusted processes can do measurement and produce the proof of system states. Through these mechanisms malicious user can not enforce attack which is feasible in current measurement architectures.

Automatic measurement of air-pressure sensor based on two-pressure control instrument

To measure the performance of high precision air-pressure sensors in below normal pressure,an automatic measurement instrument has been designed and implemented.It can simulate environment of low pressure from 300hPa to 1 000hPa with high accuracy by proportional-integral-derivative(PID)control quickly,and it can also generate various relative humidity by two-pressure control.The results show that this instrument can reach controlled pressure quickly.And it works well with the minimum average pressure difference,and the fluctuation is±0.02hPa at 500hPa.And it can keep in a stable status for a long time.It works well in performance testing of pressure sensors.The structure of the system is simple,takes small investment,and can be operated conveniently.

面向易行的高速铁路智能平行调度系统构架及关键技术

针对我国高铁成网运行、管控列车数量和种类多、运营方式复杂等特点,以构建新一代智能动态调度系统为目标,探讨面向易行的高速铁路智能平行调度系统构架,从5个方面提炼出高速铁路智能平行调度系统的技术特征。总结目前高速铁路智能平行调度系统研究亟待解决的关键技术,介绍智能高铁平行调度一体化仿真原型系统研制及实现的部分场景功能。研究工作可为建立面向易行服务的,适应中国高铁“效率变革”“质量变革”需求的智能动态调度理论与技术体系,实现我国高速铁路智能调度系统和运输服务水平的升级发展提供参考。

钻柱振动的主被动控制研究进展与展望

在油气井钻进作业过程中,钻柱长期工作在充满钻井液的狭长井筒里,其受到井底压力、摩擦、岩石硬度变化的影响,受力情况非常复杂,会产生多种形式的振动,这些是影响钻具寿命和钻进效率的最主要因素。为系统分析工程界和学术界长期以来普遍关注的钻柱系统振动的有效控制问题,对近几十年来国内外在钻杆振动控制上使用的各种方法进行了分类和归纳,总结了各种方法的特点、应用场景以及不足之处,并对钻柱系统振动控制技术的发展趋势进行了展望。研究结果表明:(1)现有的钻柱振动主动控制主要集中于单一方向(扭转振动)和2个方向的耦联振动(纵扭耦联振动),且控制参数主要集中于钻压和扭矩,仅控制单方向的振动和单参数的调节,效果将很难保证;(2)被动控制是通过改变钻柱系统自身的结构或设计参数来抑制其振动,控制过程不受结构响应和外部干扰的影响,虽然效果有较大的局限性,但仍应在设计阶段给与足够的重视;(3)今后钻柱振动控制将朝着同时基于地面和井下测量数据,纵、横、扭3个方向联合控制的方向发展。结论认为,钻杆振动往往是几种基本振动形式的耦联,并具有明显的非线性特征,基于数据驱动的钻进系统动力学建模、考虑模型不确定性的现代鲁棒自适应控制技术以及新兴的人工智能技术将会成为未来钻柱振动研究和发展的主流趋势。

高比例分布式可再生能源交直流混合配电网运行调控:科学问题与技术框架

随着分布式可再生能源发电与中低压直流组网技术的快速发展,未来配电网必然向复杂的交直流混合形态演进,其运行调控技术面临许多新的挑战。在高比例分布式可再生能源交直流混合配电网(HR-HDN)运行调控技术发展需求分析的基础上,提炼出HR-HDN运行调控技术的3个科学问题,并以多类型可控设备协同、源-网-荷-储高度互动化和市场化需求为研究主线,从稳定控制、故障主动防御与恢复、电力市场机制辅助调控以及“平台+数据”数字化集成调控4个方面,提出了HR-HDN的运行调控技术框架。最后,对HR-HDN运行调控关键技术的未来发展进行了展望。

数字时代企业的业财融合与组织韧性研究

数字时代组织的形式、边界和运营方式发生了重大转变,企业的外部经营环境也面临着宏观环境不确定性、风险突发性、多变性等多重考验,这使得组织韧性成为管理与实践领域新的研究重点。基于此,本文将业财融合这一数字时代新兴的管理模式上升至组织战略层面,基于2006—2021年中国沪深A股上市公司数据,采用双向固定效应模型实证检验业财融合对组织韧性的影响及作用机制。研究结果表明:业财融合能够提升组织韧性;业财融合对高数字化转型程度企业、CEO具有财务背景企业、高业务复杂度企业组织韧性的提升作用更显著;业财融合通过加强内部控制质量和提高投资效率提升组织韧性。本文的研究结论对企业在数字时代提升组织韧性和克服传统风险管理所面临的问题具有一定的理论价值和现实意义。

面向悬浮光力系统的集成化反馈控制器研究

悬浮光力系统具有高灵敏度、高稳定性和低耗散等特点,有望发展成为新型高性能力学传感器。针对目前悬浮光力系统存在的反馈控制器兼容性差、软硬件成本高、集成度低等问题,提出了一种兼容多种反馈控制模式的软硬件设计方案,并研制了一套高度集成的反馈控制器,在160 mm×170 mm×42 mm的尺寸上集成了六通道模数/数模转换器、滤波器、现场可编程门阵列+微处理器(FPGA+ARM)等功能模块,并且开发了基于数字锁相环和比例积分微分(PID)控制器的控制算法,最终在同一套硬件系统上实现了跨尺度微粒的运动信息采集和反馈控制,以及数十赫兹至亚兆赫兹的感知带宽。实验结果表明,该集成反馈控制器能够实现超高真空(10-6 Pa量级)下亚微米及微米尺度微粒的稳定悬浮和运动控制。在扩展系统感知带宽的同时减小了整体体积,为悬浮光力传感技术的器件化奠定了基础。

基于Kent映射的数字集群动态负载均衡算法研究

由于动态负载均衡是保证数字集群系统正常运行中不可缺少的环节,但其在控制过程中存在易受通信故障等因素的干扰问题,为此提出基于Kent映射的数字集群动态负载均衡算法。通过基于云平台的虚拟机系统采集数字集群的节点连接数、响应时间、动态负载等信息,分析数字集群系统的负载情况。其次构建数字集群资源利用率模型,通过基于Kent映射的灰狼算法对模型求解得到数字集群的资源利用率。最后将资源利用率输入LQR(Linear Quadratic Regulator)控制回路器中,通过控制服务器的迁移实现数字集群的动态负载均衡。实验结果表明,所提算法处理后的数字集群响应时间短、适应度值大、容错能力强。

基于OBE与虚实一体的测控专业实践教学改革

为解决测控专业实践教学环节存在课内和课外实践联系不够紧密、缺乏激励机制、师生合作互动度不高以及因材施教不到位等问题,提出基于OBE和虚实一体的实践教学改革。从虚实结合、内涵建设、评价及改进等方面对实践教学体系进行优化。主要措施包括以学生为中心加强校企和师生共建专业,充分利用虚拟仿真和互联网技术,让学生从线上和线下、虚拟和现实、课内和课外的各类实践资源中提高动手能力和激发创新思维。经过实践,学生的工程应用开发和创新创业能力得到明显加强,工程应用类学科竞赛获奖数以及承担的创新创业类项目数均显著增加,从而证实相关改革措施的有效性。

面向数字孪生的飞机装配测量与调控

飞机装配所涉及的内容和技术十分复杂,应用数字孪生技术可使制造人员清楚地掌握飞机装配过程中和装配后的状态,多源数字化测量技术是建立数字孪生体和实现数字孪生的基础,通过补偿、协调、调整等调控手段,可使飞机装配整个过程的几何量、力学量处于合理范围,从而保证飞机装配质量。在分析相关技术国内外应用状况的基础上,给出了基于数字孪生的飞机装配测量与调控技术的实现途径。

数字经济对湖北省城乡融合发展的影响研究

基于2010—2020年湖北省12个地级市的面板数据,通过双重固定效应模型和空间计量模型分别检验数字经济对湖北省城乡融合发展的直接影响和空间溢出影响;通过中介效应模型来探究要素流通、优化配置、就业带动、消费提升和结构升级在数字经济影响城乡融合发展过程的中介作用;最后提出对策和建议。结果表明:①数字经济不仅对本地区城乡融合有直接影响还对其他地区具有溢出效应,推动本地城乡融合发展的同时可以促进周边地区的城乡融合发展水平的提升,发挥辐射带动作用。②数字经济有助于推动城乡融合发展,并且数字经济通过要素流通、优化配置、就业带动、消费提升和结构升级进而影响湖北省城乡融合发展。

一体化边缘计算安防控制器的设计与应用研究

本文深入研究了油气场站中一体化边缘计算安防控制器的应用和技术特点,分析了边缘计算在油气行业中的发展现状,并结合实际应用案例和运行数据,探讨了一体化边缘计算安防控制器在油气场站中的优势和挑战,为油气行业的智能化转型提供了理论支持和实践指导。本文还提出了一种一体化边缘计算控制器的设计方案,旨在解决传统中央计算模式存在的延迟高、带宽压力大等问题,并通过对边缘计算安防控制器的硬件架构、软件设计以及实际应用需求的分析,验证了其在提高油气场站监控效率和实时性方面的优势。

“技防+监督”防控公立医院廉政风险的相关问题探讨

为了深入了解某省属公立医院关键重点岗位的廉政风险防控监督情况,通过问卷调查、结构化访谈等方法,全面分析了当前监督工作中存在的问题与挑战,提出了以“技防+监督”方式强化廉政风险防控的重要意义及相应解决方案。调研选取某省属公立医院的多个关键重点岗位员工作为调查对象,通过设计问卷和开展结构化访谈,收集了大量第一手资料。调研发现公立医院在廉政风险防控监督方面存在监督部门缺乏信息技术人才,监督工作的制度化、标准化程度有待提高,信息泄露、篡改等风险不容忽视。调研提出“完善制度,摸清底数,统一科学谋划;排查词库,精准聚焦,强化节点管控;梳理流程,制定表单,稳步推进联网;嵌入系统,规范运行,实现风险防控”的规范化、标准化管理解决方案,护航公立医院高质量发展。