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Fuzzy identification of nonlinear dynamic system based on selection of important input variables

Journal of systems Engineering and Electronics 2022年第3期33卷 737-747页

作者： LYU Jinfeng LIU Fucai REN Yaxue Engineering Research Center of the Ministry of Education for Intelligent Control System and Intelligent Equipment Yanshan UniversityQinhuangdao 066004China School of Mathematics and Information Science and Technology Hebei Normal University of Science and TechnologyQinhuangdao 066004China

Input variables selection(IVS) is proved to be pivotal in nonlinear dynamic system modeling. In order to optimize the model of the nonlinear dynamic system, a fuzzy modeling method for determining the premise structure by selecting important inputs of the system is studied. Firstly, a simplified two stage fuzzy curves method is proposed, which is employed to sort all possible inputs by their relevance with outputs, select the important input variables of the system and identify the ***, in order to reduce the complexity of the model, the standard fuzzy c-means clustering algorithm and the recursive least squares algorithm are used to identify the premise parameters and conclusion parameters, respectively. Then, the effectiveness of IVS is verified by two well-known issues. Finally, the proposed identification method is applied to a realistic variable load pneumatic system. The simulation experiments indi cate that the IVS method in this paper has a positive influence on the approximation performance of the Takagi-Sugeno(T-S) fuzzy modeling.

关键词： Takagi-Sugeno(T-S)fuzzy modeling input variable selection(IVS) fuzzy identification fuzzy c-means clustering algorithm

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Multilayer Multidi mensional Extension Set Theory

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Journal of Beijing Institute of Technology 2006年第2期15卷 172-176页

作者：曹少中杨国为涂序彦 School of Information Science and Technology Beijing Institute of Technology Institute of Pattern Recognition and Intelligent System Qingdao University School of Information Engineerig University of Science and Technology Beijing

In brder to study the contradiction problem of multilayer multidimensional complex systems, the concepts of extension field and stable field of intersection and union of multilayer multidimensional extension set are given. Then the related operations and properties are discussed. The results of study expand the concepts of intersection and union of extension set to a general situation, and provide the theoretical basis for production of the concepts of intersection and union of multilayer multidimensional matter element system extension set. In this way, it will be possible that matter element system theory is used to creative designs of complex systems.

关键词： multilayer multidimensional extension set extension field stable field

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New Method to Improve Dynamic Stiffness of Electro-hydraulic Servo systems

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Chinese Journal of Mechanical Engineering 2013年第5期26卷 997-1005页

作者： BAI Yanhong QUAN Long Key Laboratory of Advanced Transducers and Intelligent Control System of Ministry of Education Taiyuan University of Technology School of Electronics Information Engineering Taiyuan University of Science and Technology

Most current researches working on improving stiffness focus on the application of control *** controller in closed-loop hydraulic control system takes effect only after the controlled position is deviated,so the control action is *** dynamic performance against force disturbance and dynamic load stiffness can’t be improved evidently by advanced control *** this paper,the elementary principle of maintaining piston position unchanged under sudden external force load change by charging additional oil is *** this basis,the conception of raising dynamic stiffness of electro hydraulic position servo system by flow feedforward compensation is put *** a scheme using double servo valves to realize flow feedforward compensation is presented,in which another fast response servo valve is added to the regular electro hydraulic servo system and specially utilized to compensate the compressed oil volume caused by load impact in *** two valves are arranged in parallel to control the cylinder ***,the model of flow compensation is derived,by which the product of the amplitude and width of the valve’s pulse command signal can be *** determination rules of the amplitude and width of pulse signal are concluded by analysis and *** the proposed scheme,simulations and experiments at different positions with different force changes are *** simulation and experimental results show that the system dynamic performance against load force impact is largely improved with decreased maximal dynamic position deviation and shortened settling *** is,system dynamic load stiffness is evidently *** paper proposes a new method which can effectively improve the dynamic stiffness of electro-hydraulic servo systems.

关键词： electro-hydraulic servo system flow feedforward compensation dynamic load stiffness double-valve actuation

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Evasion strategies of a three-player lifeline game

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science China(information sciences) 2018年第11期61卷 144-154页

作者： Fan ZHANG Wenzhong ZHA School of Automation Beijing Institute of Technology State Key Laboratory of Intelligent Control and Decision of Complex System Information Science Academy China Electronics Technology Group Corporation

This study examines a multi-player pursuit-evasion game, more specifically, a three-player lifeline game in a planar environment, where a single evader is tasked with reaching a lifeline prior to capture. A decomposition method based on an explicit policy is proposed to address the game qualitatively from two main aspects:(1) the evader's position distribution to guarantee winning the game(i.e., the escape zone),which is based on the premise of knowing the pursuers' positions initially, and(2) evasion strategies in the escape zone. First, this study decomposes the three-player lifeline game into two two-player sub-games and obtains an analytic expression of the escape zone by constructing a barrier, which is an integration of the solutions of two sub-games. This study then explicitly partitions the escape zone into several regions and derives an evasion strategy for each region. In particular, this study provides a resultant force method for the evader to balance the active goal of reaching the lifeline and the passive goal of avoiding capture. Finally,some examples from a lifeline game involving more than one pursuer are used to verify the effectiveness and scalability of the evasion strategies.

关键词： lifeline game three-player pursuit-evasion game barrier evasion strategy game of kind

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Priority-based IEEE 802.15.4 CSMA/CA mechanism for WSNs

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The Journal of China Universities of Posts and Telecommunications 2013年第1期20卷 47-53页

作者： ZHAO Lu BAI Guang-wei SHEN Hang TANG Zhen-min Key Laboratory of Intelligent Perception and System for High-dimensional Information for Ministry of Education of China Nanjing University of Science and Technology School of Electronics and Information Engineering Nanjing University of Technology

The IEEE 802.15.4 standard is widely used in wireless sensor networks （WSNs）. In this paper, we propose a priority-based IEEE 802.15.4 carrier sense multiple access with collision avoidance （CSMA/CA） mechanism for WSNs. Considering traffic load and traffic type of sensor nodes, we classify sensor nodes into three types. In our mechanism, different contention parameters are set for nodes with different priority levels, in order that nodes with high priority achieve high probability to access the channel. By modeling the proposed mechanism using a Markov chain, we analyze and compute the successful transmission probability, throughput and energy consumption for nodes with different priority levels. Finally, our numerical results demonstrate that our mechanism performs well for WSNs.

关键词： WSNs 1EEE 802.15.4 MAC Markov chain priority real-time data

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Document representation methods for clustering bilingual documents

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Proceedings of the Association for information science and Technology 2016年第1期53卷 1-10页

作者： Ma, Shutian Zhang, Chengzhi He, Daqing Department of Information Management Nanjing University of Science and Technology No. 200 Xiaolingwei Street Nanjing China School of Information Science and Intelligent System Program University of Pittsburgh 135 North Bellefield Avenue PittsburghPA15260 United States

Globalization places people in a multilingual environment. There is a growing number of users to access and share information in several languages for public or private purpose. In order to deliver relevant information in different languages, efficient multilingual documents management is worthy of study. Generally, classification and clustering are two typical methods for documents management. However, lack of training data and high efforts for corpus annotation will increase the cost for classifying multilingual documents which needs to bridge language gaps as well. Clustering is more suitable to implement in such practical applications. There are two main factors involved in documents clustering, document representation method and clustering algorithm. In this paper, we focus on document representation method and demonstrate that the choice of representation methods has impacts on quality of clustering results. In our experiment, we use parallel corpora (English-Chinese documents on topic of technology information) and comparable corpora (English and Chinese documents on topics of mobile technology and wind energy) as dataset. We compare four different types of document representation methods: Vector Space Model, Latent Semantic Indexing, Latent Dirichlet Allocation and Doc2Vec. Experimental results show that, accuracy of Vector Space Model were not competitive with other methods in all clustering tasks. Latent Semantic Indexing is overly sensitive to corpora itself, for it behaved differently when clustering two different topics of comparable corpora. Latent Dirichlet Allocation behaves best when clustering documents in small size of comparable corpora while Doc2Vec behaves best for large documents set of parallel corpora. Accordingly, characteristics of corpora should be under considerations for rational utilization of document representation methods to have better performance. Copyright © 2016 by Association for information science and Technology

关键词： Digital libraries

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Modeling supports the implementation of urban greening as a response to the challenges of sustainable spatial planning

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Journal of Environmental Management 2025年 386卷 125648页

作者： Kim, Eun Sub Hyun, Jung Hee Kim, Na Yeon Heo, Su Jeong Kim, Da Seul Lee, Dong Kun Low-Carbon and Climate Impact Research Centre School of Energy and Environment City University of Hong Kong Tat Chee Ave Hong Kong Kowloon Tong China Systemic Risk and Resilience Research Group Advancing Systems Analysis International Institute for Applied Systems Analysis Austria Department of Landscape Architecture and Rural System Engineering Seoul National University Seoul08826 Korea Republic of Integrated Major in Smart City Global Convergence Program Seoul National University Seoul08826 Korea Republic of Forest Disaster & Environment Department National Institute of Forest Science Seoul Korea Republic of Interdisciplinary Program in Landscape Architecture Seoul National University Seoul08826 Korea Republic of Specialized Graduate School of Intelligent Eco-Science 4 Dept. of Landscape Architecture Seoul National University Seoul08826 Korea Republic of

Urban greening is critical for sustainable urban development, climate change mitigation, and biodiversity conservation. However, the effectiveness of urban greening varies depending on the specific goals (e.g., enhancing biodiversity, reducing urban heat, or both) and their spatial implementation. To address the spatial variability in the effectiveness of greening, we propose a spatial decision support model based on the non-dominated sorting genetic algorithm-II (NSGA-II). This model aims to optimize urban greening locations to maximize biomass density, mitigate urban heat stress, and improve landscape connectivity. Applied to Suwon City, South Korea, the model's effectiveness was evaluated against a business-as-usual (BAU) scenario across four scenarios: connectivity-based, biomass density-based, heat stress-based, and an integrated-based scenario. The integrated approach, balancing trade-offs between ecological benefits and implementation costs, outperformed the BAU scenario by 8.84 %. Despite highlighting a weaker correlation with heat stress mitigation, this outcome indicates significant improvements in biomass density and landscape connectivity. Our findings underscore the necessity of an integrated planning approach to urban greening, as it can contribute toward attaining urban development goals. Additionally, by proposing an app-based model for policymakers, our outputs should enable the reconciliation of multiple environmental objectives in urban landscapes. © 2025 Elsevier Ltd

关键词： Biotic

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Aerial-networked ISAC-empowered collaborative energy-efficient covert communications

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Chinese Journal of Aeronautics 2025年

作者： Jun WU Weijie YUAN Qin TAO Hongjia HUANG Derrick Wing Kwan NG School of System Design and Intelligent Manufacturing Southern University of Science and Technology Shenzhen 518055 China School of Information Science and Technology Hangzhou Normal University Hangzhou 311121 China School of Electrical Engineering and Telecommunications University of New South Wales Sydney NSW 2052 Australia

Covert unmanned aerial vehicle (UAV) communication has garnered considerable attention in wireless systems for realizing the sustainable low-altitude economy (LAE). This paper investigates the system policy, trajectory design, and resource allocation for energy-efficient aerial networked systems with the aid of an integrated sensing and communications (ISAC) framework, in which multiple UAVs are employed to simultaneously conduct cooperative sensing and covert downlink transmissions to multiple ground users (GUs) in the presence of a mobile warden (Willie). Specifically, to improve the communication covertness, UAVs are strategically switched between jamming (JUAV) and information (IUAV) modes. Additionally, to cope with the mobility of Willie, an unscented Kalman filtering (UKF)-based method is employed to track and predict Willie’s location relying on the delay and Doppler measurements extracted from the ISAC echoes. Capitalizing on the predicted Willie’s location, a real-time energy efficiency (EE) maximization problem is formulated by jointly optimizing the JUAV selection strategy, IUAV-GU scheduling, communication/jamming power allocation, and UAV trajectories design. The formulation takes into account the communication covertness requirement and the maximum transmit power budget, leading to a mixed-integer non-convex fractional programming. To tackle this challenge, the alternating optimization (AO) approach is adopted, which decomposes the original problem into a series of sub-problems, allowing us to obtain an efficient sub-optimal solution. Simulation results demonstrate that the proposed scheme is capable of tracking Willie accurately and offering excellent system EE performance compared to various benchmark schemes adopting existing designs.

关键词： Integrated sensing and communication Unmanned aerial vehicles Low-altitude economy Trajectory design Jammer selection

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Survival Analysis of Kasturi Tobacco Plants in Jember District using the Stratified Cox and Extended Cox Models

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MethodsX 2025年

作者： Angga Iryanto Pratama Dwi Rantini Ratih Ardiati Ningrum Arip Ramadan Fazidah Othman Data Science Technology Study Program Faculty of Advanced Technology and Multidiscipline Universitas Airlangga Surabaya 60115 Indonesia Research Group of Data-Driven Decision Support System Faculty of Advanced Technology and Multidiscipline Universitas Airlangga Surabaya 60115 Indonesia Information System Study Program School of Industrial and System Engineering Telkom University Surabaya Campus Surabaya 60231 Indonesia Department of Computer System and Technology Faculty of Computer Science and Information Technology University of Malaya Malaysia

In 2022, tobacco was the top export commodity, generating $106.3 million in sales. East Java Province contributes significantly to Indonesia's tobacco production, with an annual output of 188.6 thousand tons. Jember Regency is the area in East Java Province which is a Kasturi tobacco cultivation area. The productivity of Kasturi tobacco continues to decrease due to several factors that can affect the survival of the tobacco. This study aims to analyze the survival of Kasturi tobacco by creating stratified Cox and extended Cox models in order to handle factors that cannot fulfill the proportional hazard assumption. Based on the results of the analysis, the stratified Cox model is the best model with AIC and BIC values of 798.108 and 805.5748 respectively, while the extended Cox has AIC and BIC values of 840.2186 and 850.1732 respectively. Variables that can significantly affect the survival of Kasturi tobacco are the variable concentration of ZA fertilizer, pesticide concentration. The addition of ZA fertilizer must be appropriate, because if excessive it can cause poisoning of tobacco plants. Likewise with pesticides, if excessive it will cause damage to the leaves. This policy can increase the productivity of Kasturi tobacco. Then, Jember Regency contributes greater export capacity. • This paper aims to determine the factors that affect the survival of Kasturi tobacco plants in Jember • By using the extended Cox model, the best one is obtained using the Heaviside function with AIC and BIC values of 840.2186 and 850.1732, respectively • The stratified Cox model is better than the extended Cox model, which has AIC and BIC values of 798.108 and 805.5748, respectively

关键词： Productive Agriculture Cox Proportional Hazard Stratified Cox Extended Cox Kasturi Tobacco

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Generative API usage code recommendation with parameter concretization

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science China(information sciences) 2019年第9期62卷 51-72页

作者： Chi CHEN Xin PENG Jun SUN Zhenchang XING Xin WANG Yifan ZHAO Hairui ZHANG Wenyun ZHAO School of Computer Science Fudan University Shanghai Key Laboratory of Data Science Fudan University Shanghai Institute of Intelligent Electronics & Systems Pillar of Information System Technology and Design Singapore University of Technology and Design Research School of Computer Science Australian National University

Many programming languages and development frameworks have extensive libraries(e.g., JDK and Android libraries) that ease the task of software engineering if used effectively. With numerous library classes and sometimes intricate API(application programming interface) usage constraints, programmers often have difficulty remembering the library APIs and/or using them correctly. This study addresses this problem by developing an engine called DeepAPIRec, which automatically recommends the API usage *** to the existing proposals, our approach distinguishes itself in two ways. First, it is based on a tree-based long short-term memory(LSTM) neural network inspired by recent developments in the machinelearning community. A tree-based LSTM neural network allows us to model and reason about variable-length,preceding and succeeding code contexts, and to make precise predictions. Second, we apply data-flow analysis to generate concrete parameters for the API usage code, which not only allows us to generate complete code recommendations but also improves the accuracy of the learning results according to the tree-based LSTM neural network. Our approach has been implemented for supporting Java programs. Our experimental studies on the JDK library show that at statement-level recommendations, DeepAPIRec can achieve a top-1 accuracy of about 37% and a top-5 accuracy of about 64%, which are significantly better than the existing approaches. Our user study further confirms that DeepAPIRec can help developers to complete a segment of code faster and more accurately as compared to IntelliJ IDEA.

关键词： code recommendation API deep learning data dependency parameter concretization

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