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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

Evaluation Model and Method of Margin in Electromagnetic Environmental Effects for complex systems

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Chinese Journal of Electronics 2021年第1期30卷 171-179页

作者： TANG Shiping MAO Junfa Key Laboratory of Ministry of Education of Design and Electromagnetic Compatibility of High Speed Electronic System Shanghai Jiao Tong University Research Center for Electromagnetic Environmental Effects Southeast University

Margin is an important index in the control of Electromagnetic environmental effects(E3) and Electromagnetic compatibility(EMC) design for *** to define and verify the E3 margins of complex systems such as ships and airplanes is a difficult problem.A new method of system-level E3 margin evaluation is proposed. Based on the theory of fault tree, the evaluation model of system-level margin is *** complex system function is transformed into the equipment and subsystem that affect the function, and the relationship between margin of system-level and equipment is established. The change from margin of equipment to system-level margin is realized. According to the action process of Electromagnetic environment(EME), the verification and evaluation methods of EME domain, response domain and effect domain are put forward. The margin calculation formula of EME domain and typical electromagnetic energy coupling response are deduced. The problem of margin evaluation for equipment under different input parameters is solved. A typical application example is given. The verification test scheme is designed. The methods of electromagnetic energy radiation and injection are adopted. The system-level margin is analyzed by the data obtained from the effective test verification. The results show that the model and method are reasonable and feasible.

关键词： effect domain evaluation methods fault trees typical electromagnetic energy coupling response E3 margin evaluation response domain margin calculation formula ships EME domain complex systems Electromagnetic environmental effects electromagnetic compatibility system-level margin evaluation model complex system function

Hierarchical Self-organization of complex systems

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Chemical Research in Chinese Universities 2004年第4期20卷 440-445页

作者： CHAILi-he WENDong-sheng SchoolofEnvironmentalScienceandEngineering TianjinUniversityTianjin300072P.R.China InstituteofParticleScienceandEngineering UniversityofLeedsLeedsLS29JTUK

Researches on organization and structure in complex systems are academic and industrial fronts in modern sciences. Though many theories are tentatively proposed to analyze complex systems, we still lack a rigorous theory on them. complex systems possess various degrees of freedom, which means that they should exhibit all kinds of structures. However, complex systems often show similar patterns and structures. Then the question arises why such similar structures appear in all kinds of complex systems. The paper outlines a theory on freedom degree compression and the existence of hierarchical self-organization for all complex systems is found. It is freedom degree compression and hierarchical self-organization that are responsible for the existence of these similar patterns or structures observed in the complex systems.

关键词： complex systems Degrees of freedom Hierarchical Self-organization

Redox reactions of iron and manganese oxides in complex systems

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Frontiers of Environmental Science & Engineering 2020年第5期14卷 3-14页

作者： Jianzhi Huang Huichun Zhang Department of Civil and Environmental Engineering Case Western Reserve UniversityClevelandOH 44106USA

Conspectus:Redox reactions of Fe-and Mn-oxides play important roles in the fate and transformation of many contaminants in natural *** to experimental and analytical challenges associated with complex environments,there has been a limited understanding of the reaction kinetics and mechanisms in actual environmental systems,and most of the studies so far have only focused on simple model *** bridge the gap between simple model systems and complex environmental systems,it is necessary to increase the complexity of model systems and examine both the involved interaction mechanisms and how the interactions affected contaminant *** this Account,we primarily focused on(1)the oxidative reactivity of Mn-and Fe-oxides and(2)the reductive reactivity of Fe(Ⅱ)/iron oxides in comolex model systems toward contaminant *** effects of common metal ions such as Mn2+,Ca2+,Ni2+,Cr3+and Cu2+,ligands such as small anionic ligands and natural organic matter(NOM),and second metal oxides such as A1,Si and Ti oxides on the redox reactivity of the systems are briefly summarized.

关键词： Iron oxides Manganese oxides Reduction Oxidation complex systems Reaction kinetics and mechanisms

Engineering complex systems applied to risk management in the mining industry

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International Journal of Mining Science and Technology 2017年第4期27卷 611-616页

作者： Domingues Maria S.Q. Baptista Adelina L.F. Diogo Miguel Tato CERENA - Centre for Natural Resources and the Environment Faculty of Engineering University of Porto Porto 4200-465 Portugal CLEGI-Centre Lusiada of Research and Development in Engineering and Industrial Management University Lusiada-North Vila Nova de Famalicao 4760-108 Portugal

Related to complexity, there is a wide diversity of concepts, ranging from ‘‘systemic" to ‘‘complex", implying a need for a unified terminology. Per different authors, the main drivers of complexity can be found in human behaviour and uncertainty. This complexity, structural or dynamic can be organizational, technological, or nested in their relationship. ISO international standard 31000:2009 definition of risk management ‘‘coordinated activities to direct and control an organization with regard to risk", when applied to economic sectors, industry, services, project, or activity, it requires the use of models or theories as guidelines. Therefore, as its basic elements comprehend human behaviour and/or uncertainty, risk management to be effective and adapted as much as possible to reality, must be operational within complex systems, as already demonstrated in different R&D environments. Risk management faces demanding challenges when approaching specific and endogenous needs, such as the mining sector. This paper presents a multivariable function analysis methodology approach based on complex system modelling and through real data corresponding to a risk management tool in the mining sector.

关键词： Risk Risk management complex systems Mining Decision making

APPLICATION OF ARTIFICIAL NEURAL NETWORK IN complex systems OF REGIONAL SUSTAINABLE DEVELOPMENT

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Chinese Geographical Science 2004年第1期14卷 1-8页

作者： SHIChun PhilipJAMES GUOZhong-yang DepartmentofGeography SchoolofResourcesandEnvironmentalSciencel／KeyLaboratoryofGeographicalInformationScienceEastChinaNormalUniversityShanghai200062P.R.China TelfordInstituteofEnvironmentalsystems SchoolofEnvironmentandLifeSciencesUniversityofAlfordSalfordM66PUUK

Meeting the challenge of sustainable development requires substantial advances in understanding the interaction of natural and human systems. The dynamics of regional sustainable development could be addressed in the context of complex system thinking. Three features of complex systems are that they are uncertain, non-linear and self-organizing. Modeling regional development requires a consideration of these features. This paper discusses the feasibility of using the artificial neural networt(ANN) to establish an adjustment prediction model for the complex systems of sustainable development (CSSD). Shanghai Municipality was selected as the research area to set up the model, from which reliable prediction data were produced in order to help regional development planning. A new approach, which could help to manage regional sustainable development, is then explored.

关键词： complex systems sustainable development artificial neural network regional development

Incremental data-driven optimization of complex systems in nonstationary environments

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Science China(Information Sciences) 2018年第12期61卷 211-213页

作者： Cuie YANG Jinliang DING Yaochu JIN Tianyou CHAI State Key Laboratory of Synthetical Automation for Process Industries Northeastern University Department of Computer Science University of Surrey

Dear editor,In a complex system, many real-world optimization problems do not have explicit optimization functions or constraint functions, whereas only data from production processes are available because of the complexity of the system [1]. Thus,optimization in this scenario can generally rely on collected historical datasets, and these problems are also known as offline data-driven optimization

关键词： knowledge transfer Nonstationary Environments Surrogate Model complex systems Data-driven Optimization

PANsystems CLUSTERING ANALYSIS OF complex systems

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Applied Mathematics and Mechanics(English Edition) 1992年第6期13卷 507-514页

作者：昝廷全吴学谋 Northwest Development Institute Lanzhou University Lanzhou Wuhan Digital Engineering Institute Wuhan

In this paper, by use of equivalence operators δi and semi-equivalence operators Εi we study the clustering problems of complex systems, present δ (1,3) disconnection principle, dual transformation principle and large-scale systems decomposition principle for analizing and operating complex systems, discuss interconnectivity and disconnectivity of complex systems in detail and present some related theorems. Finally, we discuss the levels of systems according to pansystems clustering approach proposed in this paper.

关键词： complex systems Mathematical models Numerical methods

A GENERAL MATHEMATICAL FRAMEWORK OF complex systems(Ⅰ)

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Applied Mathematics and Mechanics(English Edition) 1993年第4期14卷 385-394页

作者： Zan Ting-quan Lanzhou University Lanzhou

The fundamental and simplest structure of a complex system is a *** to this idea,we plan to develop a general methematical framework of complex *** this paper,we discuss in detail the concept of systems,a general description of systems:System=(Hardware,Software,Environment),and whole-part relations,including relations between elements and systems,subsystems and systems,and between *** rules of operations of systems are given,and the induced transformations between hardware and software of systems are briefly discussed.

关键词： complex systems hardware software operations of systems induced transformations mathematical framework