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Modeling and Control of Networked Control systems

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Modeling and Control of Networked Control Systems

A data-driven reduced-order model for stiff chemical kinetics using dynamics-informed training

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作者： Li Hongbo, Sun Zengqi, Chen Badong Stale key Lab of Intelligence technology and Syslem, Department of Computer Science and technology, Tsinghua university, beijing, 100084, China

＜正＞This paper is concerned with modeling and control of the Networked control systems （NCSs）. A new general model for the considered NCSs is proposed under consideration of network-induced delay, data packet dropout and nonlinear characteristic simultaneously. Based on the given model,an optimal controller with feedback gain optimized based on gASA algorithm （genetic algorithm and Simulated anneal algorithm） is proposed. Compared to existing controllers, the proposed one is less conservative and can be applied to nonlinear NCSs. Two examples show the effectiveness of the proposed approaches.

关键词： Networked control systems (NCSs) gASA algorithm (genetic algorithm and Simulated anneal algorithm) state observer adaptive kalman filter

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Energy and AI 2024年第1期15卷 181-192页

作者： Vijayamanikandan Vijayarangan Harshavardhana A.Uranakara Shivam Barwey Riccardo Malpica galassi Mohammad Rafi Malik Mauro Valorani Venkat Raman Hong g.Im CCRC King Abdullah University of Science and TechnologyThuwalSaudi Arabia Argonne Leadership Computing Facility Argonne National LaboratoryLemontIL 60439USA Mechanical and Aerospace Engineering Department Sapienza University of RomeVia Eudossiana18Rome 00184Italy Department of Aerospace Engineering University of MichiganAnn ArborMI 48109USA

A data-based reduced-order model(ROM)is developed to accelerate the time integration of stiff chemically reacting systems by effectively removing the stiffness arising from a wide spectrum of chemical time ***,the objective of this work is to develop a ROM that acts as a non-stiff surrogate model for the time evolution of the thermochemical state vector(temperature and species mass fractions)during an otherwise highly stiff and nonlinear ignition *** model follows an encode-forecast-decode strategy that combines a nonlinear autoencoder(AE)for dimensionality reduction(encode and decode steps)with a neural ordinary differential equation(NODE)for modeling the dynamical system in the AE-provided latent space(forecasting step).By means of detailed timescale analysis by leveraging the dynamical system Jacobians,this work shows how data-based projection operators provided by autoencoders can inherently construct the latent spaces by removing unnecessary fast timescales,even more effectively than physics-based counterparts based on an eigenvalue analysis.A key finding is that the most significant degree of stiffness reduction is achieved through an end-to-end training strategy,where both AE and neural ODE parameters are optimized simultaneously,allowing the discovered latent space to be *** addition to end-to-end training,this work highlights the vital contribution of AE nonlinearity in the stiffness reduction *** the prediction of homogeneous ignition phenomena for H2-air and C2H4-air mixtures,the proposed ROM achieves several ordersof-magnitude increase in the integration time step size when compared to(a)a baseline CVODE solver for the full-chemical system,(b)statistical technique–principal component analysis(PCA),and(c)computational singular perturbation(CSP),a vetted physics-based stiffness-reducing modeling framework.

关键词： Stiff system Chemical kinetics Reacting flows Autoencoders Neural ODE

Monitoring and Warning of Landslides and Debris Flows Using an Optical Fiber Sensor technology

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Journal of Mountain Science 2011年第5期8卷 728-738页

作者： PEI Huafu CUI Peng YIN Jianhua ZHU Honghu CHEN Xiaoqing PEI Laizheng Department of Civil and Structural Engineering the Hong Kong Polytechnic University Hong Kong China Institute of Mountain Hazards and Environment CAS Chengdu 610041 China School of Earth Sciences and Engineering Nanjing University Nanjing 210093 China

Landslides and debris flows are typical geo-hazards which occur in hilly or mountainous regions. Debris flows may result from landslides. geotechnical instrumentation plays an important role in monitoring and warning of landslides and resulted debris flows. Traditional technologies for monitoring landslides and debris flows have certain limitations. The new optical fiber sensors presented in this paper can overcome those limitations. This paper presents two new optical fiber sensor systems: one is the Fiber Bragg grating (FBg)-based in-place inclinometer for monitoring landslides and the other is the FBg-based column-net system for monitoring debris flows. This paper presents the calibration results of FBg-based in-place inclinometers in laboratory. It is found that the calibration results are in good agreement with theoretical results. Both the FBg-based in-place inclinometers and the FBg-based column-net system have been installed at a site in Weijiagou valley, beichuan County, Sichuan Province of China. Some preliminary results have been obtained and reported in the paper. The advantages of the FBg monitoring systems and their potential applications are also presented.

关键词： Landslide Debris flow Fiber Bragg grating In-place inclinometer Column-net system

Review on DFT calculation of s-triazine-based carbon nitride

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Carbon Energy 2019年第1期1卷 32-56页

作者： Bicheng Zhu bei Cheng Liuyang Zhang Jiaguo Yu state key laboratory of Advanced technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhanChina School of Materials Science and Engineering Zhengzhou UniversityZhengzhouChina

To improve the photocatalytic performance of pristine photocatalysts,element doping,construction of composites and fabrication of novel nanostructures are recognized as universal modification *** methods have been experimentally verified to be effective in manifold photocatalytic application over various *** functional theory(DFT)calculation is a powerful and fundamental tool to pinpoint the intrinsic mechanism of the enhanced photocatalytic *** it holds the degree of precision ranging from atoms,molecules to unit ***,recent DFT calculation research progress of modified s-triazine-based graphitic carbon nitride(g-C3N4)systems as photocatalysts is *** specify,we collected information of doping site,formation energy,geometric,and electronic *** also discussed the synergistic effect of work function,Fermi level and band edge position on the built-in electric field,transfer route of photogenerated charge carriers and photocatalytic mechanism(traditional typeⅡor direct Z-scheme heterostructure).Moreover,we analyzed the geometric configuration,band structure,and stability of g-C3N4 nanocluster,nanoribbon,and ***,future perspective in the further theoretical revelation of g-C3N4-based photocatalysts is proposed.

关键词： charge transfer density functional theory electronic property g-C3N4 photocatalysis

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羌塘盆地中生界含油气系统

新疆石油地质 2004年第5期25卷 474-478页

作者：伍新和王成善胡建宏伊海生成都理工大学沉积地质研究所成都理工大学"油气藏地质及开发工程"国家重点实验室中国石油东方物理勘探公司北疆项目经理部成都理工大学"油气藏地质及开发工程"国家重点实验室四川成都610059

羌塘盆地位于青藏高原中北部特提斯构造域中段,是晚古生代—中生代特提斯体制下形成的一种复杂的、特殊类型的复合对称型前陆盆地,具有广泛的中生界海相沉积和中国最年轻的海相地层,沉积厚度可达万米。羌塘盆地中生代具有广泛分布且发... 详细信息

羌塘盆地位于青藏高原中北部特提斯构造域中段,是晚古生代—中生代特提斯体制下形成的一种复杂的、特殊类型的复合对称型前陆盆地,具有广泛的中生界海相沉积和中国最年轻的海相地层,沉积厚度可达万米。羌塘盆地中生代具有广泛分布且发育良好的烃源岩,烃源岩厚度大,最厚处在3000m以上,其中上三叠统的肖茶卡组、中侏罗统布曲组和夏里组有机质类型好、丰度高,有机质从成熟到过成熟均有分布,埋藏较好,其生油量巨大,是盆地油气的主要来源之一。以含油气系统理论为指导对其进行了全面分析,划分出了肖茶卡组(T3x)-曲色组(J1q)含油气系统、雀莫错组(J2q)-布曲组(J2b)含油气系统、夏里组(J2x)-索瓦组(J3s)含油气系统。

关键词：羌塘盆地中生界含油气系统烃源岩

Half a century after their discovery:Structural insights into exonuclease and annealase proteins catalyzing recombineering

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Engineering Microbiology 2024年第1期4卷 39-54页

作者： Lucy J.Fitschen Timothy P.Newing Nikolas P.Johnston Charles E.Bell gökhan Tolun School of Chemistry and Molecular Bioscience and Molecular HorizonsUniversity of WollongongWollongongNSWAustralia The ARC Training Centre for Cryo-electron Microscopy of Membrane Proteins University of WollongongWollongongNSWAustralia Faculty of Science University of Technology SydneyUltimoNSW 2007Australia Department of Biological Chemistry and Pharmacology The Ohio State University College of MedicineColumbusOH 43210

Recombineering is an essential tool for molecular biologists,allowing for the facile and efficient manipulation of bacterial genomes directly in cells without the need for costly and laborious in vitro manipulations involving restriction *** main workhorses behind recombineering are bacteriophage proteins that promote the single-strand annealing(SSA)homologous recombination pathway to repair double-stranded DNA *** there have been several reviews examining recombineering methods and applications,comparatively few have focused on the mechanisms of the proteins that are the key players in the SSA pathway:a 5′→3′exonuclease and a single-strand annealing protein(SSAP or“annealase”).This review dives into the structures and functions of the two SSA recombination systems that were the first to be developed for recombineering in ***:the RecET system from *** Rac prophage and the𝜆Red system from bacteriophageλ.By comparing the structures of the RecT and Red𝛽annealases,and the RecE and𝜆Exo exonucleases,we provide new insights into how the structures of these proteins dictate their *** the sequence conservation of the𝜆λExo and RecE exonucleases gives more profound insights into their critical functional ***,as recombineering accelerates and evolves in the laboratory,a better understanding of the mechanisms of the proteins behind this powerful technique will drive the development of improved and expanded capabilities in the future.

关键词： Recombineering Redβ λExo RecE RecT Protein structure Annealase Exonuclease

Ethylene oligomerization by novel iron(Ⅱ) diimine complexes/MAO

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Chinese Science Bulletin 2002年第19期47卷 1616-1618页

作者： WANg Hang, YAN Weidong, JIANg Tao, LIU Binbin, XU Wenqing, MA Jianjiang & HU Youliangstate key laboratory of Engineering Plastics, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, beijing 100080, China graduate Student of state key Lab. of Eng. Plastics Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China grad. Student Chinese Acad. of Sci. Beijing 100039 China Inst. of Polymer Science/Engineering School of Chemical Engineering Hebei University of Technology Tianjin 300130 China Dept. of Petrochemical Engineering Daqing Petroleum Institute Anda 151400 China Res. Inst. Dushanzi Petrochem. Co. PetroChina Xinjiang 833600 China

Two novel Fe(Ⅱ) diimine complexes have been synthesized. In combination with MAO, they generate active catalytic systems that oligomerize ethylene with both high catalytic activity and high selectivity for a-olefins. The effects of substituents on the aryl ring, reaction temperatures and molar ratios of Al/Fe on catalytic activity and product distribution are studied.

关键词： late-transition-metal catalysts ethylene oligomerization α-olefin.

AHTD法铜基催化剂合成甲醇的研究——Ⅱ.催化剂氧化态前驱体的性质

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燃料化学学报 1992年第2期20卷 131-137页

作者：胡云行蔡俊修万惠霖蔡启瑞厦门大学化学系固体表面物理化学国家重点实验室厦门361005

本文采用XRD,XPS,TPR等手段对AHTD(雾化高温分解)法制备的铜基甲醇合成催化剂的氧化态前驱体进行了表征,发现CuO/ZnO催化剂是四方结构的CuO和六方结构的ZnO组成的两相体系,但是,有部分ZnO溶解到CuO相中,催化剂的表面积为5—10m^2.g,远... 详细信息

本文采用XRD,XPS,TPR等手段对AHTD(雾化高温分解)法制备的铜基甲醇合成催化剂的氧化态前驱体进行了表征,发现CuO/ZnO催化剂是四方结构的CuO和六方结构的ZnO组成的两相体系,但是,有部分ZnO溶解到CuO相中,催化剂的表面积为5—10m^2.g,远小于相应的沉淀法催化剂的表面积,氧化铝的加入有助于表面积的增大;催化剂存在表面富锌现象,随着催化剂铜含量的增加,表面富锌量增大;CuO与ZnO之间存在相互作用,使CuO的还原性能发生明显的变化。

关键词：雾化高温分解铜催化剂甲醇

β-甲基萘长链烷基化产物的气相色谱-质谱分析

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分析测试学报 2003年第6期22卷 74-77页

作者：赵忠奎乔卫红王秀娜李宗石程侣伯大连理工大学精细化工国家重点实验室辽宁大连116012

采用气相色谱 -质谱联用 (gC -MS)技术 ,基于优化的色谱分析条件对 β_甲基萘长链烷基化产物的组成及其含量进行分析 ;产物得到了很好的分离 ,共分离出48个峰 ,用面积归一化法测定其相对含量 ,采用气相色谱 -质谱法对组分进行了表征 ;... 详细信息

采用气相色谱 -质谱联用 (gC -MS)技术 ,基于优化的色谱分析条件对 β_甲基萘长链烷基化产物的组成及其含量进行分析 ;产物得到了很好的分离 ,共分离出48个峰 ,用面积归一化法测定其相对含量 ,采用气相色谱 -质谱法对组分进行了表征 ;结果表明 ,甲基萘烷基化反应产物非常复杂 ,除目标产物己基甲基萘、二己基甲基萘外 ,还存在己基甲基四氢萘、己基萘、己基多甲基萘等副产物 ;本文建立一种便捷、可靠的甲基萘长链烷基化工艺评价手段 ,为反应条件的优化、反应机理的探讨及新型催化体系的研究和开发创造了条件。

关键词： β-甲基萘长链烷基化气相色谱-质谱分析表征己基甲基萘二己基甲基萘