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Recent advances in heterogeneous hydrosilylation of unsaturated carbon-carbon bonds

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Chinese Chemical Letters 2024年第6期35卷 71-85页

作者： Heng Yang zhijie zhou Conghui Tang Feng Chen School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The hydrosilylation of unsaturated carbon-carbon bonds is one of the most critical reactions in silicone industrial *** homogeneous Speier's catalyst,Karstedt's catalyst,and other noble metal-based catalysts are widely ***,simplifying the separation of the homogeneous catalyst from reaction products and reducing the high cost of precious metals is still *** review describes the recent development of heterogeneous catalysts for alkene,alkyne,and allene hydrosilylations,which can effectively solve problems in homogeneous hydrosilylation.

关键词： Hydrosilylation Heterogeneous catalysis Alkenes Alkynes Silanes

Performance evaluation of complex systems using evidential reasoning approach with uncertain parameters

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Chinese Journal of Aeronautics 2021年第1期34卷 194-208页

作者： Leiyu CHEN zhijie zhou Changhua HU Ruihua YUE Zhichao FENG High-Tech Institute of Xi’an Xi’an 710025China Harbin Institute of Technology Harbin 150001China

The composition of the modern aerospace system becomes more and more *** performance degradation of any device in the system may cause it difficult for the whole system to keep normal working ***,it is essential to evaluate the performance of complex aerospace *** this paper,the performance evaluation of complex aerospace systems is regarded as a Multi-Attribute Decision Analysis(MADA)*** on the structure and working principle of the system,a new Evidential Reasoning(ER)based approach with uncertain parameters is proposed to construct a nonlinear optimization model to evaluate the system *** the model,the interval form is used to express the uncertainty,such as error in testing data and inaccuracy in expert *** order to analyze the subsystems that have a great impact on the performance of the system,the sensitivity analysis of the evaluation result is carried out,and the corresponding maintenance strategy is *** a type of Inertial Measurement Unit(IMU)used in a rocket,the proposed method is employed to evaluate its ***,the parameter sensitivity of the evaluation result is analyzed,and the main factors affecting the performance of IMU are ***,the comparative study shows the effectiveness of the proposed method.

关键词： Complex systems Evidential reasoning approach Interval value Performance evaluation Uncertain parameters

A novel combination belief rule base model for mechanical equipment fault diagnosis

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Chinese Journal of Aeronautics 2022年第5期35卷 158-178页

作者： Manlin CHEN zhijie zhou Bangcheng ZHANG Guanyu HU You CAO High-Tech Institute of Xi’an Xi’an 710025China School of Applied Technology Changchun University of TechnologyChangchun 130000China Guangxi Key Laboratory of Trusted Software Guilin University of Electronic TechnologyGuilin 541004China

Due to the excellent performance in complex systems modeling under small samples and uncertainty,Belief Rule Base(BRB)expert system has been widely applied in fault ***,the fault diagnosis process for complex mechanical equipment normally needs multiple attributes,which can lead to the rule number explosion problem in BRB,and limit the efficiency and *** solve this problem,a novel Combination Belief Rule Base(C-BRB)model based on Directed Acyclic Graph(DAG)structure is proposed in this *** dispersing numerous attributes into the parallel structure composed of different sub-BRBs,C-BRB can effectively reduce the amount of calculation with acceptable *** the same time,a path selection strategy considering the accuracy of child nodes is designed in C-BRB to obtain the most suitable ***,a fusion method based on Evidential Reasoning(ER)rule is used to combine the belief rules of C-BRB and generate the final *** illustrate the effectiveness and reliability of the proposed method,a case study of fault diagnosis of rolling bearing is conducted,and the result is compared with other methods.

关键词： Fault diagnosis Belief rule base Directed acyclic graph Evidential reasoning Mechanical equipment

A hidden fault prediction model based on the belief rule base with power set and considering attribute reliability

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Science China(Information Sciences) 2019年第10期62卷 86-101页

作者： zhijie zhou Zhichao FENG Changhua HU Xiaoxia HAN Zhiguo zhou Gailing LI High-Tech Institute of Xi'an Department of Radiation Oncology The University of Texas Southwestern Medical Center

Hidden faults are important characteristics of complex systems that cannot be observed *** hidden behavior of a system, such as the health state and safety level, has a direct correlation with these hidden faults. After the predicted hidden behavior reaches a fault boundary, certain measures must be taken to avoid fault occurrences. Thus, hidden faults can be predicted by the hidden behavior of a *** belief rule base(BRB) has been used to predict hidden behaviors. However, two problems remain to be solved in engineering practice. First, when the observed information is absent, ignorance may exist in the output. If only global ignorance is considered, it may be unreasonable in certain cases, which can influence the prediction model. Second, the effects of disturbance factors such as noise and sensor quality may cause the reliability of the gathered information to decline, which indirectly leads to unreliability of the hidden behavior. Thus, to address the global ignorance and unreliable hidden behavior, a new hidden BRB model with a power set and considering attribute reliability(PHBRB-r) is proposed for hidden fault prediction. In the PHBRB-r model, the effects of disturbance factors on hidden behavior are considered using attribute reliability, and the discernment frame is a power set. A case study of hidden fault prediction is conducted to demonstrate the effectiveness of the PHBRB-r model.

关键词： fault diagnosis fault prediction belief rule base hidden behavior attribute reliability power set

Sensor Fault Diagnosis and Tolerant Control Based on Belief Rule Base for Complex System

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Journal of Systems Science & Complexity 2023年第3期36卷 1002-1023页

作者： FENG Zhichao zhou zhijie BAN Xiaojun HU Changhua ZHANG Xiaobo Rocket Force University of Engineering Xi'an 710025China Harbin Institute of Technology Harbin 150001China

This paper develops a new fault diagnosis and tolerant control framework of sensor failure(SFDTC)for complex system such as rockets and *** new framework aims to solve two problems:The lack of data and the multiple uncertainty of *** the SFDTC framework,two parts exist:The fault diagnosis model and the output reconstruction *** two parts of the new framework are constructed based on the new developed belief rule base with power set(BRB-PS).The multiple uncertainty of knowledge can be addressed by the local ignorance and global ignorance in the new developed BRB-PS ***,the stability of the developed framework is proved by the output error of the BRB-PS *** complex system,the sensor state is determined by many factors and experts cannot provide accurate *** multiple uncertain knowledge will reduce the performance of the initial SDFTC ***,in the SFDTC framework,to handle the influence of the uncertainty of expert knowledge and improve the framework performance,a new optimization model with two optimization goals is developed to ensure the smallest output uncertainty and the highest accuracy simultaneously.A case study is conducted to illustrate the effectiveness of the developed framework.

关键词： Belief rule base fault diagnosis and tolerant control optimization model uncertainty

New health-state assessment model based on belief rule base with interpretability

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Science China(Information Sciences) 2021年第7期64卷 209-223页

作者： zhijie zhou You CAO Guanyu HU Youmin ZHANG Shuaiwen TANG Yuan CHEN High-Tech Institute of Xi'an Department of Information and Control Engineering Xi'an University of Technology School of Computer Science and Information Security Guilin University of Electronic Technology Department of Mechanical Industrial and Aerospace Engineering Concordia University

Health-state assessment is the foundation of optimal-maintenance decision-making for complex systems to maintain reliability and safety. Generating the assessment results in a convincing and interpretable way to avoid potential risks is of great importance. Belief rule base(BRB) as an interpretable model performs well in health-state assessment. However, the interpretability of a BRB-based model may be lost during the optimization process, which is expressed mainly as three problems: expert knowledge is not effectively used in the optimization process; the optimized rules of BRB may be in conflict with real systems; and some parameters get over-optimized, which may affect experts’ initial judgment. Three concepts — "searching intensity", "interpretability constraint of belief distribution", and "rule-activation factor" — are defined to address these problems. Using these concepts, we propose a new health-state assessment model based on the interpretable BRB and a new optimization method to improve the accuracy and preserve the interpretability of the new model. To demonstrate the effectiveness of the proposed model, we conducted an aero-engine case study.

关键词： health-state assessment belief rule base interpretability complex systems

A New Safety Assessment Method Based on Belief Rule Base With Attribute Reliability

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IEEE/CAA Journal of Automatica Sinica 2021年第11期8卷 1774-1785页

作者： Zhichao Feng Wei He zhijie zhou Xiaojun Ban Changhua Hu Xiaoxia Han Rocket Force University of Engineering Xi’an 710025China Harbin Normal University Harbin 150080China Harbin Institute of Technology Harbin 150001China

Safety assessment is one of important aspects in health *** safety assessment for practical systems,three problems exist:lack of observation information,high system complexity and environment *** rule base with attribute reliability(BRB-r)is an expert system that provides a useful way for dealing with these three *** BRB-r,once the input information is unreliable,the reliability of belief rule is influenced,which further influences the accuracy of its output belief *** the other hand,when many system characteristics exist,the belief rule combination will explode in BRB-r,and the BRB-r based safety assessment model becomes too complicated to be ***,in this paper,to balance the complexity and accuracy of the safety assessment model,a new safety assessment model based on BRB-r with considering belief rule reliability is developed for the first *** the developed model,a new calculation method of the belief rule reliability is proposed with considering both attribute reliability and global ***,to reduce the influence of uncertainty of expert knowledge,an optimization model for the developed safety assessment model is constructed.A case study of safety assessment of liquefied natural gas(LNG)storage tank is conducted to illustrate the effectiveness of the new developed model.

关键词： Belief rule base(BRB) belief rule reduction reliability safety assessment structure adjustment

On the evidential reasoning rule for dependent evidence combination

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Chinese Journal of Aeronautics 2023年第5期36卷 306-327页

作者： Peng ZHANG zhijie zhou Shuaiwen TANG Jie WANG Guanyu HU Dao ZHAO You CAO Rocket Force University of Engineering Xi’an 710025China State Key Laboratory of Astronautic Dynamics Xi’an Satellite Control CenterXi’an 710043China Guangxi Key Laboratory of Trusted Software Guilin University of Electronic TechnologyGuilin 541004China

Evidential Reasoning(ER)rule,which can combine multiple pieces of independent evidence conjunctively,is widely applied in multiple attribute decision ***,the assumption of independence among evidence is often not satisfied,resulting in ER rule *** this paper,an Evidential Reasoning rule for Dependent Evidence combination(ERr-DE)is ***,the aggregation sequence of multiple pieces of evidence is determined according to evidence *** this basis,a calculation method of evidence Relative Total Dependence Coefficient(RTDC)is proposed using the distance correlation ***,as a discounting factor,RTDC is introduced into the ER rule framework,and the ERr-DE model is *** aggregation process of two pieces of dependent evidence by ERr-DE is investigated,which is then generalized to aggregate multiple pieces of non-independent ***,sensitivity analysis is carried out to investigate the relationship between the model output and the *** properties of sensitivity coefficient are explored and mathematically *** conjunctive probabilistic reasoning process of ERr-DE and the properties of sensitivity coefficient are verified by two numerical examples ***,the practical application of the ERr-DE is validated by a case study on the performance assessment of satellite turntable system.

关键词： Evidential reasoning rule Dependent evidence Relative total dependence coefficient Aggregation sequence Performance assessment

Reliability Analysis of Satellite Turntable System under Multiple Operation Modes Based on Multi-Valued Decision Diagrams

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Journal of Beijing Institute of Technology 2023年第1期32卷 52-68页

作者： Peng Zhang zhijie zhou Yao Ding Dao Zhao Yijun Zhang the Key Laboratory for Fault Diagnosis and Maintenance of Spacecraft in Orbit Xi’anShaanxi 710043China the High-Tech Institute of Xi’an Xi’anShaanxi 710025China Institute of Information and Communication National University of Defense TechnologyWuhan 430079China

As a payload support system deployed on satellites,the turntable system is often switched among different working modes during the on-orbit operation,which can experience great state *** each mode,the missions to be completed are different,consecutive and non-over-lapping,from which the turntable system can be considered to be a phased-mission system(PMS).Reliability analysis for PMS has been widely ***,the system mode cycle characteristic has not been taken into account *** this paper,reliability analysis method of the satellite turntable system is proposed considering its multiple operation modes and mode cycle ***,the multi-valued decision diagrams(MDD)manipulation rules between two adjacent mission cycles are *** this basis,MDD models for the turntable system in different states are established and the reliability is calculated using the continuous time Markov chains(CTMC)***,the comparative study is carried out to show the effectiveness of our proposed method.

关键词： phased-mission systems multi-valued decision diagrams continuous time Markov chains(CTMC) reliability analysis satellite turntable system