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Global finite-time stabilization design for a class of high-order uncertain nonlinear systems

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Journal of Harbin Institute of Technology(New Series) 2012年第3期19卷 77-80页

作者：孟桂芝马克茂张佳为 Control and Simulation Center Harbin Institute of Technology Dept.of Applied Mathematics Harbin University of Science and Technology

The problem of finite-time stabilization for uncertain nonlinear systems is investigated.It is proved that a class of high-order nonlinear systems in the lower-triangular form is globally stabilized via non-Lipschitz continuous state feedback.By using the finite-time Lyapunov stability theorem and the method of non-smooth feedback design,a recursive design procedure is provided,which guarantees the finite-time stability of the closed-loop system.The simulation results show the effectiveness of the theoretical results.

关键词： finite-time stability continuous state feedback non-smooth control high-order nonlinear system

Comparison of Linearized Kalman Filter and Extended Kalman Filter for Satellite Motion States Estimation

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Journal of Measurement Science and Instrumentation 2011年第4期2卷 307-311页

作者：杨亚非 control & simulation center Harbin Institute of Technology

The performance of the conventional Kalman filter depends on process and measurement noise statistics given by the system model and measurements.The conventional Kalman filter is usually used for a linear system,but it should not be used for estimating the state of a nonlinear system such as a satellite motion because it is difficult to obtain the desired estimation results.The linearized Kalman filtering approach and the extended Kalman filtering approach have been proposed for a general nonlinear system.The equations of satellite motion are described.The satellite motion states are estimated,and the relevant estimation errors are calculated through the estimation algorithms of the both above mentioned approaches implemented in Matlab are estimated.The performances of the extended Kalman filter and the linearized Kalman filter are compared.The simulation results show that the extended Kalman filter is much better than the linearized Kalman filter at the aspect of estimation effect.

关键词：扩展卡尔曼滤波器非线性系统状态估计卫星运动卡尔曼滤波方法卡尔曼滤波估计 Matlab 测量过程

A VV&A evaluation system based on hierarchical evaluation

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Journal of Harbin Institute of Technology(New Series) 2005年第2期12卷 184-188页

作者：方可杨明王子才 Control and Simulation Center Harbin Institute of Technology Harbin 150001 China

Evaluation is the major activity of performing Verification, Validation and Accreditation (VV&A) of a simulation system. Unfortunately, there is a lack of reasonable and operable evaluation methods. Moreover, there are other problems to address in VV&A evaluation, such as index definition, conclusion analysis, etc. In this paper, a VV&A evaluation system is introduced to try to resolve these problems. The system is based on a method called hierarchical evaluation, and it uses a good combination of evaluation processes and indexes. First, a thorough analysis of the VV&A evaluation’s essentials and principles are given, then the uncertainty of the evaluation results caused by various analysis of the evaluators is pointed out, then a hierarchical evaluation mechanism based on evaluator weight and evaluation hierarchy is brought forward, and finally a comprehensive VV&A evaluation system with evaluation flow processing, index management and hierarchical evaluation fulfillment is established. The system gives good consideration to ease of operation, reasonableness of evaluation conclusion, and the ability to comprehensively resolve VV&A problems. Since VV&A is attracting more and more recognition, it is meaningful to provide a good system for implementing credible simulation systems. It is hoped that this VV&A evaluation will provide a good way.

关键词： VV&A 评价体系等级评价可信性仿真技术

Interoperability and Development Process Model of the Embedded simulation System

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Interoperability and Development Process Model of the Embedd...

Hybrid Modeling and Predictive control of A Fractionated Satellite System: A Mixed Logical Dynamical Approach 25th

第25届中国控制与决策会议

作者： Xiaochao Qian Wei Li Ming Yang Control and Simulation Center Harbin Institute of Technology

ISBN: (纸本)9781467355339

The development of embedded simulation system is different from that of general simulation system. Several problems are studied for guiding the development of embedded simulation system. The concept of embedded simulation system is defined. simulation system is first introduced into the embedded simulation field as the embedded system. An embedded simulation Interoperability Technical Reference Model （ITRM） is introduced in the purpose of providing a reference framework and measurement method for the interoperability design. An embedded simulation Development Process Model （DPM） is also introduced to guide the development of embedded simulation system. The ITRM and DPM can provide guidance with the development of embedded simulation system and achieve interoperability.

关键词： Embedded simulation Interoperability Development process model

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Hybrid Modeling and Predictive Control of A Fractionated Sat...

Reduction of wastewater toxicity and change of microbial community in a hydrolysis acidification reactor pre-treating trimethylolpropane wastewater

第25届中国控制与决策会议

作者： Xiaoping Shi Hailong Liu Long Li Control and Simulation Center Harbin Institute of Technology

ISBN: (纸本)9781467355339

This paper proposes a model and predictive control of a fractionated satellite system by using Mixed Logic Dynamical （MLD） approach. The power management system of a fractionated satellite can be seen as a hybrid system, which includes discrete dynamics, continuous dynamics, and logic rules. Discrete features of the power management system are the different types of flight modes and discrete inputs. On the other hand, continuous dynamics feature is power consumption process in each mode. The union of these properties characterizes the hybrid behavior of a power management system. In order to model both the discrete/continuous dynamics and the switching between different flight modes, the MLD framework has been exploiting. Then, predictive control scheme is proposed to control this hybrid system. To illustrate the effectiveness of the proposed approach, some numerical simulations are shown.

关键词： Fractionated satellite Hybrid system Mix logical dynamics Modeling Predictive control

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Frontiers of Environmental Science & Engineering 2018年第6期12卷 119-131页

作者： Xin Xing Yin Yu Hongbo Xi Guangqing Song Yajiao Wang Jiane Zuo Yuexi Zhou State Key Joint Laboratory of Environment simulation and Pollution control School of EnvironmentTsinghua UniversityBeijing 100084China Research center of Water Pollution control Technology Chinese Research Academy of Environmental SciencesBeijing 100012China

HAP was verified to reduce the toxicity of TMP wastewater effectively. Actual TMP wastewater was fed in HAP with different dilution ratios for 240 days. Formaldehyde, 2-ethylacrolein, TMP and 2-ethylhexanol were all g... 详细信息

关键词： Trimethylolpropane wastewater Hydrolysis acidification process Toxicity Oxygen uptake rate 16S rDNA

Design of formation flight control based on virtual body frame of the team formation 25th

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Design of formation flight control based on virtual body fra...

Discovery of emerging organic pollutants in the atmosphere through an omics approach

第25届中国控制与决策会议

作者： Xiaoping Shi Jing Yang Control and Simulation Center Harbin Institute of Technology

ISBN: (纸本)9781467355339

In this paper, novel concepts of virtual body frame and body attitude of the team formation are proposed. A corroding to this definition, a nonlinear control algorithm is designed for the formation unmanned aerial vehicles （UAVs） in three dimensions. Based on the novel error formulation of follower and leader vehicles in the inertial frame, control command is developed for the follower vehicles’ velocity, yaw angle and pitching angle. The simulation on the control system of equilateral triangle formation flight presents that the algorithm is fast and accurate to realize the tracking control command without collision. Further more, it can give an intuitive observation and description of the formation plane’s adjustment in the inertial frame compared with the traditional methods;such demonstrates the correctness and effectiveness of the design.

关键词： formation flight control autopilot aerial vehicle

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Frontiers of Environmental Science & Engineering 2023年第4期17卷 71-81页

作者： Zhen Cheng Xinghua Qiu Xiaodi Shi Xing Jiang Tong Zhu State Key Joint Laboratory for Environmental simulation and Pollution control College of Environmental Sciences and EngineeringCenter for Environment and HealthPeking UniversityBeijing 100871China

Ambient air pollution,containing numerous known and hitherto unknown compounds,is a major risk factor for public health.The discovery of harmful components is the prerequisite for pollution control;however,this raises a great challenge on recognizing previously unknown species.Here we systematically review the analytical techniques on air pollution in the framework of an omics approach,with a brief introduction on sample preparation and analysis,and in more detail,compounds prioritization and identification.Through high-resolution mass spectrometry(HRMS,typically coupled with chromatography),the complicated environmental matrix can be digitalized into“fullcomponent”data.A key step to discover emerging compounds is the prioritization of compounds from massive data.Chemical fingerprints,suspect lists and biological effects are the most vital untargeted strategies for comprehensively screening critical and hazardous substances.Afterward,compressed data of compounds can be identified at various confidence levels according to exact mass and the derived molecular formula,MS libraries,and authentic standards.Such an omics approach on full-component data provides a paradigm for discovering emerging air pollutants;nonetheless,new technological advancements of instruments and databases are warranted for further tracking the environmental behaviors,hence to evaluate the health risk of key pollutants.

关键词： Air pollution Emerging pollutants Full-component High-resolution mass spectrometry Omics approach

Shape dependence of support for NO_x storage and reduction catalysts

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Journal of Environmental Sciences 2019年第1期31卷 396-407页

作者： Wen Xie Yunbo Yu Hong He State Key Joint Laboratory of Environment simulation and Pollution control Research Center for Eco-Environmental SciencesChinese Academy of Sciences University of Chinese Academy of Sciences center for Excellence in Regional Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences

Pt/BaO/Al_2O_3 catalysts with different BaO loadings prepared from Al_2O_3 nanorods(Pt/BaO/Al_2O_3-nr) and irregular Al_2O_3 nanoparticles(Pt/BaO/Al_2O_3-np) were investigated for NOx storage and reduction(NSR). The Pt/BaO/Al_2O_3 materials derived from Al_2O_3 nanorods always exhibited much higher NOx storage capacity(NSC) over the whole temperature range of 100–400°C than the corresponding Pt/BaO/Al_2O_3-np samples containing the same BaO loading, giving the maximum NSC value of 966.9 μmol/gcatat 400°C, 1.4 times higher than that of Pt/BaO/Al_2O_3-np. Higher catalytic performance of nanorod-supported NSR samples was also observed during lean-rich cyclic conditions(90 sec vs. 5 sec), giving more than 98% NOx conversion at 300–450°C over the Pt/BaO/Al_2O_3-nr sample with 15% BaO loading. To reveal this dependence on the shape of the support during the NSR process, a series of characterization techniques including the Brunauer–Emmett–Teller(BET) method,X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), H_2 temperature programmed reduction(H2-TPR), and in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS) were also conducted. It was found that intimate contact of Ba–Al and Ba–Pt sites was achieved over the Pt/BaO/Al_2O_3 surface when using Al_2O_3-nr as a support.This strong interaction among the multi-components of Pt/BaO/Al_2O_3-nr thus triggered the formation of surface nitrite and nitrate during the lean period, and also accelerated the reverse spillover of ad-NOxspecies onto the Pt surface, enhancing their reduction and leading to high NSR performance.

关键词： NOx storage and reduction Pt/BaO/Al2O3 Nanorod Morphology effect Strong interaction