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A Health State Prediction Model Based on Belief Rule Base and LSTM for Complex Systems
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作者 Yu Zhao Zhijie Zhou +3 位作者 Hongdong Fan Xiaoxia Han JieWang Manlin Chen 《Intelligent Automation & Soft Computing》 2024年第1期73-91,共19页
In industrial production and engineering operations,the health state of complex systems is critical,and predicting it can ensure normal operation.Complex systems have many monitoring indicators,complex coupling struct... In industrial production and engineering operations,the health state of complex systems is critical,and predicting it can ensure normal operation.Complex systems have many monitoring indicators,complex coupling structures,non-linear and time-varying characteristics,so it is a challenge to establish a reliable prediction model.The belief rule base(BRB)can fuse observed data and expert knowledge to establish a nonlinear relationship between input and output and has well modeling capabilities.Since each indicator of the complex system can reflect the health state to some extent,the BRB is built based on the causal relationship between system indicators and the health state to achieve the prediction.A health state prediction model based on BRB and long short term memory for complex systems is proposed in this paper.Firstly,the LSTMis introduced to predict the trend of the indicators in the system.Secondly,the Density Peak Clustering(DPC)algorithmis used todetermine referential values of indicators for BRB,which effectively offset the lack of expert knowledge.Then,the predicted values and expert knowledge are fused to construct BRB to predict the health state of the systems by inference.Finally,the effectiveness of the model is verified by a case study of a certain vehicle hydraulic pump. 展开更多
关键词 Health state predicftion complex systems belief rule base expert knowledge LSTM density peak clustering
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Patterns of Interactions of the Complex City System:Emotional Urban Objects as Triggering Agents-A Secondary Publication
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作者 O.A.Gonzalez Liliana Beatriz Sosa Compeán 《Journal of World Architecture》 2024年第1期45-53,共9页
This article presents an analysis of the patterns of interactions resulting from the positive and negative emotional events that occur in cities,considering them as complex systems.It explores,from the imaginaries,how... This article presents an analysis of the patterns of interactions resulting from the positive and negative emotional events that occur in cities,considering them as complex systems.It explores,from the imaginaries,how certain urban objects can act as emotional agents and how these events affect the urban system as a whole.An adaptive complex systems perspective is used to analyze these patterns.The results show patterns in the processes and dynamics that occur in cities based on the objects that affect the emotions of the people who live there.These patterns depend on the characteristics of the emotional charge of urban objects,but they can be generalized in the following process:(1)immediate reaction by some individuals;(2)emotions are generated at the individual level which begins to generalize,permuting to a collective emotion;(3)a process of reflection is detonated in some individuals from the reading of collective emotions;(4)integration/significance in the community both at the individual and collective level,on the concepts,roles and/or functions that give rise to the process in the system.Therefore,it is clear that emotions play a significant role in the development of cities and these aspects should be considered in the design strategies of all kinds of projects for the city.Future extensions of this work could include a deeper analysis of specific emotional events in urban environments,as well as possible implications for urban policy and decision making. 展开更多
关键词 Emotional events Urban objects complex adaptive systems Adaptive complex systems City
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Systematic Risk Analysis of Listed Financial Institutions from the Perspective of Complex Network
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作者 Shiyun Li 《Proceedings of Business and Economic Studies》 2024年第1期104-110,共7页
Based on the complex network theory,this paper studies the systemic financial risks in China’s financial market.According to the industry classification of the China Securities Regulatory Commission in 2012,the daily... Based on the complex network theory,this paper studies the systemic financial risks in China’s financial market.According to the industry classification of the China Securities Regulatory Commission in 2012,the daily closing prices of 45 listed financial institutions are collected and the daily return rates of each financial institution are measured according to the logarithmic return rate calculation formula.In this paper,the risk spillover value ΔCoVaR is used to measure the contribution degree of each financial institution to systemic risk.Finally,the relationship between the risk spillover valueΔCoVaR and the node topology index of the risk transmission network is investigated by using a regression model,and some policy suggestions are put forward based on the regression results. 展开更多
关键词 complex network systemic risk GARCH model
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The Golden Ratio Theorem: A Framework for Interchangeability and Self-Similarity in Complex Systems
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作者 Alessandro Rizzo 《Advances in Pure Mathematics》 2023年第9期559-596,共38页
The Golden Ratio Theorem, deeply rooted in fractal mathematics, presents a pioneering perspective on deciphering complex systems. It draws a profound connection between the principles of interchangeability, self-simil... The Golden Ratio Theorem, deeply rooted in fractal mathematics, presents a pioneering perspective on deciphering complex systems. It draws a profound connection between the principles of interchangeability, self-similarity, and the mathematical elegance of the Golden Ratio. This research unravels a unique methodological paradigm, emphasizing the omnipresence of the Golden Ratio in shaping system dynamics. The novelty of this study stems from its detailed exposition of self-similarity and interchangeability, transforming them from mere abstract notions into actionable, concrete insights. By highlighting the fractal nature of the Golden Ratio, the implications of these revelations become far-reaching, heralding new avenues for both theoretical advancements and pragmatic applications across a spectrum of scientific disciplines. 展开更多
关键词 Conservation Law SELF-SIMILARITY INTERCHANGEABILITY Golden Ratio complex systems Dynamic Exchange Structural Stability Mathematical Modeling Theoretical Framework P vs NP Millennium Problem
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Auxiliary Software for Defining the Parameters of the Structural Organization of a Complex System
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作者 Branislav M. Savic 《Journal of Software Engineering and Applications》 2024年第2期109-128,共20页
The developed auxiliary software serves to simplify, standardize and facilitate the software loading of the structural organization of a complex technological system, as well as its further manipulation within the pro... The developed auxiliary software serves to simplify, standardize and facilitate the software loading of the structural organization of a complex technological system, as well as its further manipulation within the process of solving the considered technological system. Its help can be especially useful in the case of a complex structural organization of a technological system with a large number of different functional elements grouped into several technological subsystems. This paper presents the results of its application for a special complex technological system related to the reference steam block for the combined production of heat and electricity. 展开更多
关键词 complex system Structural Organization Auxiliary Software PARAMETERS
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Hierarchical Self-organization of Complex Systems 被引量:27
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作者 CHAILi-he WENDong-sheng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第4期440-445,共6页
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 the... 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. 展开更多
关键词 complex systems Degrees of freedom HIERARCHICAL SELF-ORGANIZATION
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Engineering complex systems applied to risk management in the mining industry 被引量:7
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作者 Domingues Maria S.Q. Baptista Adelina L.F. Diogo Miguel Tato 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第4期611-616,共6页
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 ... 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. 展开更多
关键词 RISK Risk management complex systems MINING Decision making
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Numerical Simulation of the Fractional-Order Lorenz Chaotic Systems with Caputo Fractional Derivative
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作者 Dandan Dai Xiaoyu Li +2 位作者 Zhiyuan Li Wei Zhang Yulan Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第5期1371-1392,共22页
Although some numerical methods of the fractional-order chaotic systems have been announced,high-precision numerical methods have always been the direction that researchers strive to pursue.Based on this problem,this ... Although some numerical methods of the fractional-order chaotic systems have been announced,high-precision numerical methods have always been the direction that researchers strive to pursue.Based on this problem,this paper introduces a high-precision numerical approach.Some complex dynamic behavior of fractional-order Lorenz chaotic systems are shown by using the present method.We observe some novel dynamic behavior in numerical experiments which are unlike any that have been previously discovered in numerical experiments or theoretical studies.We investigate the influence of α_(1),α_(2),α_(3) on the numerical solution of fractional-order Lorenz chaotic systems.The simulation results of integer order are in good agreement with those of othermethods.The simulation results of numerical experiments demonstrate the effectiveness of the present method. 展开更多
关键词 Novel complex dynamic behavior numerical simulation fractional-order lorenz chaotic systems HIGH-PRECISION
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Low-Cost Embedded Controller for Complex Control Systems 被引量:1
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作者 Long-Hua Ma Xiao-Long Shi +2 位作者 Hui Li Zhe-Ming Lu Meng Shao 《Journal of Electronic Science and Technology》 CAS 2013年第1期89-95,共7页
Because of limited resource of embedded platforms, the computational complexity of advanced control algorithms raises significant challenges for the use of embedded systems in complex control field. A Scilab/Scicos ba... Because of limited resource of embedded platforms, the computational complexity of advanced control algorithms raises significant challenges for the use of embedded systems in complex control field. A Scilab/Scicos based embedded controller is developed on which various control software can be easily modeled, simulated, implemented, and evaluated to meet the ever-expanding requirements of industrial control applications. Built on the Cirrus Logic EP9315 ARM systems-on-chip board, this embedded controller is possible to develop complex embedded control systems that employ advanced control strategies in a rapid and cost-efficient fashion. Due to the free and open source nature of the software packages used, the cost of the embedded controller is minimized. 展开更多
关键词 complex control embedded systems SCILAB system optimization system-on-chip.
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Intrinsic Noise Monitoring of Complex Systems 被引量:2
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作者 Oliver Szasz Gyula Peter Szigeti Andras Szasz 《Open Journal of Biophysics》 2017年第4期197-215,共19页
The power-density function of the noise spectrum of open and complex systems changes by the power of frequency. We show that the fluctuation origin and the noise-powered description are equivalent to describe the colo... The power-density function of the noise spectrum of open and complex systems changes by the power of frequency. We show that the fluctuation origin and the noise-powered description are equivalent to describe the colored noise power density. Based on this, we introduce a scale-independent invariant for monitoring the dynamics of the complex system. The monitoring of the noise spectrum of the system specifies the forecast of failure, the timing of desired regular corrections and/or the assessed operation life of the system, indicating the possible faults before it happens, predicting deterioration like wear/tear, fatigue in the still properly working system. These considerations are highly applicable to living systems and their preventive care. 展开更多
关键词 Power Density complex systems REGULAR Maintenance system INVARIANT FLUCTUATION DIAGNOSTICS
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Establishment of New Solution for Complex Systems in Multidisciplinary Sci-ence Based on Feedback System Analysis Method and Proven by Simulator 被引量:3
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作者 Deok-Soo Cha 《Journal of Modern Physics》 2015年第13期1927-1934,共8页
This paper establishes a very important scientific solution to science of complexity for physicists, and presents a multidisciplinary involved physics and engineering. The innovative solution for complex systems prese... This paper establishes a very important scientific solution to science of complexity for physicists, and presents a multidisciplinary involved physics and engineering. The innovative solution for complex systems presented here is verified on the basis of principles in engineering such as feed-back-system analysis using the classical control theory. This paper proposes that a complex system is a closed-loop system with a negative feedback element and is a solvable problem. A complex system can be analyzed using the system analysis theory in control engineering, and its behavior can be realized using a specially designed simulator. 展开更多
关键词 complex systems Feedback system system SIMULATOR system Modeling MULTIDISCIPLINARY
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A Novel Method for Vibration Mitigation of Complex Mechanical Systems 被引量:2
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作者 Cheng Hu 《Sound & Vibration》 2019年第5期199-206,共8页
Taking the complex mechanical systems as the research project,a theoretical multi-degree-of-freedom(MDOF)model was established.Based on the vibration characteristics analysis of this system,a novel method of vibration... Taking the complex mechanical systems as the research project,a theoretical multi-degree-of-freedom(MDOF)model was established.Based on the vibration characteristics analysis of this system,a novel method of vibration mitigation was proposed,which can be applied to most of the complex mechanical systems.Through this method,limited grounding stiffness was made use of and added to certain degree of freedom(DOF)discretely.Thus,the root-meansquare(RMS)of the systems amplitude can be reduced to ideal level.The MATLAB code based on this method was attached,which was tested on the theoretical model.Consider that complex mechanical systems are nonlinear and uncertain,theoretically the optimal solution of vibration mitigation is inaccessible.However,this method can always provide a relatively effective solution. 展开更多
关键词 ibration mitigation complex mechanical systems grounding stiffness MDOF MATLAB
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A Novel Evolutionary-Fuzzy Control Algorithm for Complex Systems 被引量:1
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作者 王攀 徐承志 +1 位作者 冯珊 徐爱华 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2002年第3期52-60,共9页
This paper presents an adaptive fuzzy control scheme based on modified genetic algorithm. In the control scheme, genetic algorithm is used to optimze the nonlinear quantization functions of the controller and some key... This paper presents an adaptive fuzzy control scheme based on modified genetic algorithm. In the control scheme, genetic algorithm is used to optimze the nonlinear quantization functions of the controller and some key parameters of the adaptive control algorithm. Simulation results show that this control scheme has satisfactory performance in MIMO systems, chaotic systems and delay systems. 展开更多
关键词 Modified genetic algorithm Nonlinear quantization factor Adaptive fuzzy controller ITAE index complex systems.
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Decentralized Variable Structure Control of Complex Giant Singular Uncertainty Systems 被引量:1
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作者 Wen Xiangcai&Liu Yongqing (Department of Automation, South China University of Technology Guangzhou, 510641, P. R. China.) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1996年第1期23-34,共12页
This paper, at the first time, considers the problem of decentralized variable structure control of complex giant singular uncertainty systems by using the property of diagonally dominant matrix and Frobenius-Person t... This paper, at the first time, considers the problem of decentralized variable structure control of complex giant singular uncertainty systems by using the property of diagonally dominant matrix and Frobenius-Person theorem. The splendid selection of switching manifold for each subsystem makes the design relatively straightforward and can be easily realized. An illustrate example is given. 展开更多
关键词 complex giant singular uncertainty systems Multiple input interconnected Decentralized variable structure control Sliding mode Completely controllable.
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Approximate Solutions to the Discontinuous Riemann-Hilbert Problem of Elliptic Systems of First Order Complex Equations 被引量:1
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作者 Guochun Wen Yanhui Zhang Dechang Chen 《Applied Mathematics》 2014年第10期1546-1556,共11页
Several approximate methods have been used to find approximate solutions of elliptic systems of first order equations. One common method is the Newton imbedding approach, i.e. the parameter extension method. In this a... Several approximate methods have been used to find approximate solutions of elliptic systems of first order equations. One common method is the Newton imbedding approach, i.e. the parameter extension method. In this article, we discuss approximate solutions to discontinuous Riemann-Hilbert boundary value problems, which have various applications in mechanics and physics. We first formulate the discontinuous Riemann-Hilbert problem for elliptic systems of first order complex equations in multiply connected domains and its modified well-posedness, then use the parameter extensional method to find approximate solutions to the modified boundary value problem for elliptic complex systems of first order equations, and then provide the error estimate of approximate solutions for the discontinuous boundary value problem. 展开更多
关键词 DISCONTINUOUS RIEMANN-HILBERT Problem ELLIPTIC systems of First Order complex EQUATIONS Esti-mates and EXISTENCE of Solutions Multiply Connected DOMAINS
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IoT-based Smart and Complex Systems:A Guest Editorial Report 被引量:4
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作者 Naiqi Wu Zhiwu Li +3 位作者 Kamel Barkaoui Xiaoou Li Tadahiko Murata MengChu Zhou 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2018年第1期69-73,共5页
THE Industrial Revolution starting from about 1760 and ending at around 1840 has been viewed as the first Industrial Revolution.It features with the replacement of human and animal muscle power with steam and mechanic... THE Industrial Revolution starting from about 1760 and ending at around 1840 has been viewed as the first Industrial Revolution.It features with the replacement of human and animal muscle power with steam and mechanical power.Human income per capita had taken 800 years to double by 展开更多
关键词 In IoT-based Smart and complex systems:A Guest Editorial Report
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Preliminary Study on the Effect of Different Ecological Cultivation Modes on the Water Stability of Soil Aggregates in Rubber Based Agroforestry Systems
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作者 Shiyun Zhan Fengyue Qin +4 位作者 Dongling Qi Zhixiang Wu Chuan Yang Yingying Zhang Qingmao Fu 《Open Journal of Ecology》 2023年第11期782-793,共12页
Rubber trees (Hevea brasiliensis Müll. Arg.) have been commercially cultivated for a century and a half in Asia, particularly in China, and they constitute a common element of plantation ecosystems in tropical re... Rubber trees (Hevea brasiliensis Müll. Arg.) have been commercially cultivated for a century and a half in Asia, particularly in China, and they constitute a common element of plantation ecosystems in tropical regions. Soil health is fundamental to the sustainable development of rubber plantations. The objective of the study is to explore the influence of different complex ecological cultivation modes on the stability of soil aggregates in rubber based agroforestry systems. In this study, the ecological cultivation mode of rubber—Alpinia oxyphylla plantation, the ecological cultivation mode of rubber—Phrynium hainanense plantations, the ecological cultivation mode of rubber—Homalium ceylanicum plantations and monoculture rubber plantations were selected, and the particle size distribution of soil aggregates and their water stability characteristics were analyzed. The soil depth of 0 - 20 cm and 20 - 40 cm was collected for four cultivation modes. Soil was divided into 6 particle levels > 20 cm. soil was divided into 6 particle levels > 5 mm, 2 - 5 mm, 1 - 2 mm, 0.5 - 1 mm, 0.25 - 0.5 mm, and 0.053 - 0.25 mm according to the wet sieve method. The particle size proportion and water stability of soil aggregates were determined by the wet sieve method. The particle size proportion and water stability of soil aggregates under different ecological cultivation modes were analyzed. The results showed that under different ecological cultivation modes in the shallow soil layer (0 - 20 cm), the rubber—Alpinia oxyphylla plantation and the rubber—Phrynium hainanense plantation promoted the development of dominant soil aggregates towards larger size classes, whereas the situation is the opposite for rubber—Homalium ceylanicum plantation. In soil layer (20 - 40 cm), the ecological cultivation mode of rubber—Phrynium hainanense plantation developed the dominant radial level of soil aggregates to the diameter level of large aggregates. Rubber—Alpinia oxyphylla plantation and rubber—Homalium ceylanicum plantation, three indicators, including the water-stable aggregate content R<sub>0.25</sub> (>0.25 mm water-stable aggregates), mean weight diameter (MWD), and geometric mean diameter (GMD), were all lower than those in the rubber monoculture mode. However, in the rubber—Phrynium hainanense plantation, the water-stable aggregate content R<sub>0.25</sub>, mean weight diameter, and geometric mean diameter were higher than in the rubber monoculture mode, although these differences did not reach statistical significance. 展开更多
关键词 Ecological complex Cultivation Rubber Plantation Soil Aggregates Soil Aggregate Water Stability Rubber Based Agroforestry systems
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A BiLSTM cardinality estimator in complex database systems based on attention mechanism 被引量:1
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作者 Qiang Zhou Guoping Yang +6 位作者 Haiquan Song Jin Guo Yadong Zhang Shengjie Wei Lulu Qu Louis Alberto Gutierrez Shaojie Qiao 《CAAI Transactions on Intelligence Technology》 SCIE EI 2022年第3期537-546,共10页
An excellent cardinality estimation can make the query optimiser produce a good execution plan.Although there are some studies on cardinality estimation,the prediction results of existing cardinality estimators are in... An excellent cardinality estimation can make the query optimiser produce a good execution plan.Although there are some studies on cardinality estimation,the prediction results of existing cardinality estimators are inaccurate and the query efficiency cannot be guaranteed as well.In particular,they are difficult to accurately obtain the complex relationships between multiple tables in complex database systems.When dealing with complex queries,the existing cardinality estimators cannot achieve good results.In this study,a novel cardinality estimator is proposed.It uses the core techniques with the BiLSTM network structure and adds the attention mechanism.First,the columns involved in the query statements in the training set are sampled and compressed into bitmaps.Then,the Word2vec model is used to embed the word vectors about the query statements.Finally,the BiLSTM network and attention mechanism are employed to deal with word vectors.The proposed model takes into consideration not only the correlation between tables but also the processing of complex predicates.Extensive experiments and the evaluation of BiLSTM-Attention Cardinality Estimator(BACE)on the IMDB datasets are conducted.The results show that the deep learning model can significantly improve the quality of cardinality estimation,which is a vital role in query optimisation for complex databases. 展开更多
关键词 ATTENTION BiLSTM cardinality estimation complex database systems query optimiser Word2vec
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On the Order of the Solutions of Systems of Complex Algebraic Differential Equations 被引量:1
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作者 SU Xian-feng GAO Ling-yun 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第2期196-199,共4页
This paper is concerned with the order of the solutions of systems of high-order complex algebraic differential equations.By means of Zalcman Lemma,the systems of equations of[1]is extended to more general form.
关键词 normal family order systems of complex algebraic differential equations
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Design and Optimization of Multiple Interconnected Utility Systems in An Integrated Refining and Petrochemical Complex 被引量:1
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作者 Bai Haobo Li Shiyu +1 位作者 Wang Xupeng Liu Chang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2020年第4期126-136,共11页
In an integrated refining and petrochemical complex,a centralized utility system(CUS)is introduced to integrate the steam demands of production plants.Besides,two sub-utility systems(SUSs)located inside the alkene and... In an integrated refining and petrochemical complex,a centralized utility system(CUS)is introduced to integrate the steam demands of production plants.Besides,two sub-utility systems(SUSs)located inside the alkene and refinery plants,respectively,can satisfy the shaft demands.It is difficult to determine the steam production of the CUS because the steam demands of the alkene and refinery plants also depend on the design and operation of the SUSs.To explore the complicated interaction between the CUS and SUSs,we proposed a mixed-integer nonlinear programming(MINLP)model for the design and optimization of multiple interconnected utility systems to minimize the total annualized cost(TAC).An extended superstructure was suggested to contain multiple inter-plant connected steam pipe alternatives between the CUS and SUSs.A more accurate model of the complex steam turbine was proposed.Then the proposed MINLP framework is applied to a new integrated refining and petrochemical complex.Two scenarios are investigated in the case study to explore the effect of steam main temperatures on system configurations and operating parameters.By optimizing the main temperatures,a TAC of$2.7 million can be saved.Judging from the results of the two scenarios,the feasibility and effectiveness of the proposed framework for the design and optimization of multiple interconnected utility systems have been demonstrated. 展开更多
关键词 MINLP model multiple interconnected utility systems complex steam turbines steam main temperatures
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