空中交通CPS结构特性及韧性评估

针对空中交通体系结构复杂、耦合性强、脆弱性高的特点,为缓解因受扰导致的级联失效现象,对其结构韧性进行研究。建立了空中交通信息物理系统(CPS)模型,提出同层度与层间度、同层介数与层间介数等指标,分析级联失效过程;提出空中交通CPS韧性的概念,并采用定量评估方法对受损能力和恢复能力进行度量;对比不同扰动-恢复策略下的空中交通CPS表现,制定最佳恢复策略,提高受扰时的韧性。以华东地区空中交通CPS为例进行分析,结果表明:空中交通CPS网络度分布服从幂率分布,介数服从指数分布;在基于介数度值扰动下,采用介数恢复策略可以有效提高受扰时空中交通CPS的韧性。

CPS-SPWM级联H桥激励的变压器铁耗快速计算方法

针对载波移相(CPS)正弦脉宽调制(SPWM)级联H桥激励的变压器,提出一种基于经典损耗分离模型的铁耗快速计算方法.首先,结合SPWM电压波形特征定义集总占空比,并推导其关于调制比的解析模型;其次,基于经典损耗分离模型和集总占空比,构建CPS-SPWM级联H桥的铁耗计算模型,该方法可以直接使用调制比、直流母线电压等参数对铁耗进行计算,从而避免传统方法中的谐波分析或者数值积分过程;再次,基于本文铁耗计算模型,提出了一种针对SPWM电压激励的有限元(FEM)仿真等效方法,最后,通过实验验证了本文计算方法的有效性.研究结果表明:等效仿真铁耗误差小于3.6%、仿真用时减少74.5%;最大铁耗计算误差为7.6%.

新工科背景下CPS与工业物联网实践课程教学探索

CPS与工业物联网实践课程是高等学校智能制造工程新工科专业的一门专业实践必修课。本文首先介绍了 CPS与工业物联网实践课程,然后分析了CPS与工业物联网实践课程的特征,再提出了学生参与度不强、实践项目创新 度不够、三大项目之间关联度不强和课程考核方式单一四大难题,最后提出科学分组、紧跟生产实践/分享创新案例、串 联三大实践项目和丰富课程考核方式四种教学改革措施,为高等院校智能制造人才培养提供参考。

针对电力CPS数据驱动算法对抗攻击的防御方法

大规模电力电子设备的接入为系统引入了数量庞大的强非线性量测/控制节点,使得传统电力系统逐渐转变为电力信息物理系统(cyber-physical system,CPS),许多原本应用模型驱动方法解决的系统问题不得不因维度灾难等局限转而采取数据驱动算法进行分析。然而,数据驱动算法自身的缺陷为系统的安全稳定运行引入了新的风险,攻击者可以对其加以利用,发起可能引发系统停电甚至失稳的对抗攻击。针对电力CPS中数据驱动算法可能遭受的对抗攻击,从异常数据剔除与恢复、算法漏洞挖掘与优化、算法自身可解释性提升3个方面,提出了对应的防御方法:异常数据过滤器、基于生成式对抗网络(generative adversarial network,GAN)的漏洞挖掘与优化方法、数据-知识融合模型及其训练方法,并经算例分析验证了所提方法的有效性。

Conventional Geothermal Systems and Unconventional Geothermal Developments: An Overview

This paper provides an overview of conventional geothermal systems and unconventional geothermal developments as a common reference is needed for discussions between energy professionals. Conventional geothermal systems have the heat, permeability and fluid, requiring only drilling down to °C, normal heat flow or decaying radiogenic granite as heat sources, and used in district heating. Medium-temperature (MT) 100°C - 190°C, and high-temperature (HT) 190°C - 374°C resources are mostly at plate boundaries, with volcanic intrusive heat source, used mostly for electricity generation. Single well capacities are °C - 500°C) and a range of depths (1 m to 20 Km), but lack permeability or fluid, thus requiring stimulations for heat extraction by conduction. HVAC is 1 - 2 m deep and shallow geothermal down to 500 m in wells, both capturing °C, with °C are either advanced by geothermal developers at <7 Km depth (Enhanced Geothermal Systems (EGS), drilling below brittle-ductile transition zones and under geothermal fields), or by the Oil & Gas industry (Advanced Geothermal Systems, heat recovery from hydrocarbon wells or reservoirs, Superhot Rock Geothermal, and millimeter-wave drilling down to 20 Km). Their primary aim is electricity generation, relying on closed-loops, but EGS uses fractures for heat exchange with earthquake risks during fracking. Unconventional approaches could be everywhere, with shallow geothermal already functional. The deeper and hotter unconventional alternatives are still experimental, overcoming costs and technological challenges to become fully commercial. Meanwhile, the conventional geothermal resources remain the most proven opportunities for investments and development.

Computational Experiments for Complex Social Systems:Experiment Design and Generative Explanation

Powered by advanced information technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).In this context,computational experiments method has emerged as a novel approach for the design,analysis,management,control,and integration of CPSS,which can realize the causal analysis of complex systems by means of“algorithmization”of“counterfactuals”.However,because CPSS involve human and social factors(e.g.,autonomy,initiative,and sociality),it is difficult for traditional design of experiment(DOE)methods to achieve the generative explanation of system emergence.To address this challenge,this paper proposes an integrated approach to the design of computational experiments,incorporating three key modules:1)Descriptive module:Determining the influencing factors and response variables of the system by means of the modeling of an artificial society;2)Interpretative module:Selecting factorial experimental design solution to identify the relationship between influencing factors and macro phenomena;3)Predictive module:Building a meta-model that is equivalent to artificial society to explore its operating laws.Finally,a case study of crowd-sourcing platforms is presented to illustrate the application process and effectiveness of the proposed approach,which can reveal the social impact of algorithmic behavior on“rider race”.

Prescribed Performance Tracking Control of Time-Delay Nonlinear Systems With Output Constraints

The problem of prescribed performance tracking control for unknown time-delay nonlinear systems subject to output constraints is dealt with in this paper. In contrast with related works, only the most fundamental requirements, i.e., boundedness and the local Lipschitz condition, are assumed for the allowable time delays. Moreover, we focus on the case where the reference is unknown beforehand, which renders the standard prescribed performance control designs under output constraints infeasible. To conquer these challenges, a novel robust prescribed performance control approach is put forward in this paper.Herein, a reverse tuning function is skillfully constructed and automatically generates a performance envelop for the tracking error. In addition, a unified performance analysis framework based on proof by contradiction and the barrier function is established to reveal the inherent robustness of the control system against the time delays. It turns out that the system output tracks the reference with a preassigned settling time and good accuracy,without constraint violations. A comparative simulation on a two-stage chemical reactor is carried out to illustrate the above theoretical findings.

基于CPS的异构数据交互模型设计研究

针对传统多源异构数据集成模型难以在信息物理融合系统(Cyber-physical system,CPS)中采用中间件实现异构系统概念层关系映射、传输性能低和系统拓展性差等问题,设计出一个基于CPS的异构数据交互模型。所设计模型可实现仿真和物理系统的概念映射;定义控制类和监测类元数据,并根据各类数据采取全量字段或增量字段更新以减轻网络负载;以Protobuf协议为基础搭建通信模型,使系统扩展性能大幅提升;以高层体系结构(High level architecture,HLA)/数据分析服务(Data distribution service,DDS)搭建异构系统交互模型,有效确保CPS的交互实时性。

Finite-time Prescribed Performance Time-Varying Formation Control for Second-Order Multi-Agent Systems With Non-Strict Feedback Based on a Neural Network Observer

This paper studies the problem of time-varying formation control with finite-time prescribed performance for nonstrict feedback second-order multi-agent systems with unmeasured states and unknown nonlinearities.To eliminate nonlinearities,neural networks are applied to approximate the inherent dynamics of the system.In addition,due to the limitations of the actual working conditions,each follower agent can only obtain the locally measurable partial state information of the leader agent.To address this problem,a neural network state observer based on the leader state information is designed.Then,a finite-time prescribed performance adaptive output feedback control strategy is proposed by restricting the sliding mode surface to a prescribed region,which ensures that the closed-loop system has practical finite-time stability and that formation errors of the multi-agent systems converge to the prescribed performance bound in finite time.Finally,a numerical simulation is provided to demonstrate the practicality and effectiveness of the developed algorithm.

人-信息-物理系统(HCPS)在图书馆中的应用

图书馆由人、信息系统和物理系统(HCPS)组成。研究HCPS的内涵及各组成部分的关系,可为图书馆的发展指明方向。通过对早期图书馆、现代图书馆和智慧图书馆的特征分析,将HCPS理论引入图书馆中,并基于HCPS视角探讨了图书馆的演变过程,分析了不同阶段图书馆HCPS的特点与作用,提出了智慧图书馆HCPS的研究框架和重点研究内容,剖析了推动图书馆发展的赋能技术,进行了智慧图书馆HCPS的实践应用与讨论。信息系统的引入及发展助力了图书馆的演变,建立智慧图书馆HCPS的重点是开展信息系统模型的建立与仿真方法研究。初次探索HCPS在图书馆中的应用,提出的概念和研究框架仍处于探索阶段,后续需要广泛地跨学科合作与交流,不断充实和细化图书馆HCPS的研究内容、方法和技术。

A Review on Security and Privacy Issues Pertaining to Cyber-Physical Systems in the Industry 5.0 Era

The advent of Industry 5.0 marks a transformative era where Cyber-Physical Systems(CPSs)seamlessly integrate physical processes with advanced digital technologies.However,as industries become increasingly interconnected and reliant on smart digital technologies,the intersection of physical and cyber domains introduces novel security considerations,endangering the entire industrial ecosystem.The transition towards a more cooperative setting,including humans and machines in Industry 5.0,together with the growing intricacy and interconnection of CPSs,presents distinct and diverse security and privacy challenges.In this regard,this study provides a comprehensive review of security and privacy concerns pertaining to CPSs in the context of Industry 5.0.The review commences by providing an outline of the role of CPSs in Industry 5.0 and then proceeds to conduct a thorough review of the different security risks associated with CPSs in the context of Industry 5.0.Afterward,the study also presents the privacy implications inherent in these systems,particularly in light of the massive data collection and processing required.In addition,the paper delineates potential avenues for future research and provides countermeasures to surmount these challenges.Overall,the study underscores the imperative of adopting comprehensive security and privacy strategies within the context of Industry 5.0.

基于CPS和VMD的实时电力需求饱和自适应预测

电力数据具有非平稳性和随机性的特点,导致电力需求预测结果误差较大,为此,提出基于CPS和VMD的实时电力需求饱和自适应预测方法。基于CPS与VMP建立自适应变分模态分解模型,利用实时电力需求序列和各模态分解余量之间的信息散度差来判断相关性程度,实现模态分解,通过自适应模态分解得到电力需求序列的分解余量,依靠其建立自适应预测模型,并对模型进行训练,完成对实时电力需求饱和自适应预测。实验结果表明,设计方法预测结果的平均绝对误差低于5.0,平均绝对百分比误差低于2.45%。

CPS1基因新发变异致氨基甲酰磷酸合成酶1缺乏症1例并文献复习

目的提高氨基甲酰磷酸合成酶1缺乏症表型及基因型认识。方法回顾性分析中南大学湘雅二医院儿童医学中心新生儿专科1例氨基甲酰磷酸合成酶1缺乏症的诊治过程。结果男性患儿,17 d,因出生后反应差,反复吐奶17 d入院。血串联质谱示瓜氨酸3.63~4.35μmol/L,血氨波动于117.12~905.4μmol/L;全外显子基因测序发现CPS1基因母源性c.1912C>T无义变异和父源性c.3389C>A错义变异,确诊氨基甲酰磷酸合成酶1缺乏症。CPS1基因c.3389C>A变异位点未见文献报道。结论对反应差及呕吐新生儿,需警惕尿素循环障碍,积极基因检测可明确诊断。

6.25 m焦炉CPS系统常见问题分析及改进

三钢6.25 m 3号焦炉采用炭化室压力稳定系统,简称CPS系统,该应用可以实现焦炉无烟装煤以及结焦过程中各炭化室的压力稳定。CPS系统依据装煤、出焦信号,自动完成相应操作,提高了焦炉生产的自动化水平。在投产前期,CPS系统经常出现问题,但通过不断摸索、研究,并针对性地进行改进处理后,相关故障基本上得以消除。

CPS防水卷材在公路房建项目施工中的应用

结合甘肃省某国道服务区升级改造项目消防蓄水池、地埋式污水处理设施防水施工管理现状,从CPS防水卷材的材料性能、防水施工原理、工艺特点、材料选用、防水施工质量管控、工程细部处理等角度出发,通过与传统防水卷材施工工艺的对比分析,总结了CPS防水卷材在经济效益和安全环保效益等方面所具有的优势,总结、探讨提升房建项目地下工程防水施工质量的技术保障措施。

Computation Tree Logic Model Checking of Multi-Agent Systems Based on Fuzzy Epistemic Interpreted Systems

Model checking is an automated formal verification method to verify whether epistemic multi-agent systems adhere to property specifications.Although there is an extensive literature on qualitative properties such as safety and liveness,there is still a lack of quantitative and uncertain property verifications for these systems.In uncertain environments,agents must make judicious decisions based on subjective epistemic.To verify epistemic and measurable properties in multi-agent systems,this paper extends fuzzy computation tree logic by introducing epistemic modalities and proposing a new Fuzzy Computation Tree Logic of Knowledge(FCTLK).We represent fuzzy multi-agent systems as distributed knowledge bases with fuzzy epistemic interpreted systems.In addition,we provide a transformation algorithm from fuzzy epistemic interpreted systems to fuzzy Kripke structures,as well as transformation rules from FCTLK formulas to Fuzzy Computation Tree Logic(FCTL)formulas.Accordingly,we transform the FCTLK model checking problem into the FCTL model checking.This enables the verification of FCTLK formulas by using the fuzzy model checking algorithm of FCTL without additional computational overheads.Finally,we present correctness proofs and complexity analyses of the proposed algorithms.Additionally,we further illustrate the practical application of our approach through an example of a train control system.

Optimal Multi-Timescale Scheduling of Integrated Energy Systems with Hybrid Energy Storage System Based on Lyapunov Optimization

The economic operation of integrated energy system(IES)faces new challenges such as multi-timescale characteristics of heterogeneous energy sources,and cooperative operation of hybrid energy storage system(HESS).To this end,this paper investigates the multi-timescale rolling opti-mization problem for IES integrated with HESS.Firstly,the architecture of IES with HESS is established,a comparative analysis is conducted to evaluate the advantages of the HESS over a single energy storage system(SESS)in stabilizing power fluctuations.Secondly,the dayahead and real-time scheduling cost functions of IES are established,the day-ahead scheduling mainly depends on operation costs of the components in IES,the real-time optimal scheduling adopts the Lya-punov optimization method to schedule the battery and hydrogen energy storage in each time slot,so as to minimize the real-time average scheduling operation cost,and the problem of day-ahead and real-time scheduling error,which caused by the uncertainty of the energy storage is solved by online optimization.Finally,the proposed model is verified to reduce the scheduling operation cost and the dispatching error by performing an arithmetic example analysis of the IES in Shanghai,which provides a reference for the safe and stable operation of the IES.

Anomalous time-reversal symmetric non-Hermitian systems

The conditions for the emergence of the non-Hermitian skin effect, as a unique physical response of non-Hermitian systems, have now become one of the hot research topics. In this paper, we study the novel physical responses of nonHermitian systems with anomalous time-reversal symmetry, in both one dimension and two dimensions. Specifically, we focus on whether the systems will exhibit a non-Hermitian skin effect. We employ the theory of generalized Brillouin zone and also numerical methods to show that the anomalous time-reversal symmetry can prevent the skin effect in onedimensional non-Hermitian systems, but is unable to exert the same effectiveness in two-dimensional cases.

Numerical simulation for the initial state of avalanche in polydisperse particle systems

Numerical simulation is employed to investigate the initial state of avalanche in polydisperse particle systems.Nucleation and propagation processes are illustrated for pentadisperse and triadisperse particle systems,respectively.In these processes,particles involved in the avalanche grow slowly in the early stage and explosively in the later stage,which is clearly different from the continuous and steady growth trend in the monodisperse system.By examining the avalanche propagation,the number growth of particles involved in the avalanche and the slope of the number growth,the initial state can be divided into three stages:T1(nucleation stage),T2(propagation stage),T3(overall avalanche stage).We focus on the characteristics of the avalanche in the T2 stage,and find that propagation distances increase almost linearly in both axial and radial directions in polydisperse systems.We also consider the distribution characteristics of the average coordination number and average velocity for the moving particles.The results support that the polydisperse particle systems are more stable in the T2 stage.

Quantum discord and its dynamics for multipartite systems

Quantum discord, one of the famous quantum correlations, has been recently generalized to multipartite systems by Radhakrishnan et al. Here we give analytical solutions of the quantum discord for a family of N-qubit quantum states. For the bipartite system, we derive a zero quantum discord which will remain unchanged under the phase damping channel. For multiparitite systems, it is found that the quantum discord can be classified into three categories and the quantum discord for odd-partite systems can exhibit freezing under the phase damping channel, while the freezing does not exist in the even-partite systems.