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Journal of Systems Engineering and Electronics 2014年第5期25卷 735-741页

作者： hamidreza hosseinzadeh Department of Electrical and Computer Engineering Science and Research BranchIslamic Azad University

Automatic modulation classification is the process of identification of the modulation type of a signal in a general environment. This paper proposes a new method to evaluate the tracking performance of large margin classifier against signal-tonoise ratio （SNR）, and classifies all forms of primary user＇s signals in a cognitive radio environment. For achieving this objective, two structures of a large margin are developed in additive white Gaussian noise （AWGN） channels with priori unknown SNR. A combination of higher order statistics and instantaneous characteristics is selected as effective features. Simulation results show that the classification rates of the proposed structures are well robust against environmental SNR changes.

关键词： automatic modulation classification (AMC) tracking performance evaluation passive-aggressive (PA) classifier self- training cognitive radio (CR).

Molecular Structure Tailoring of Organic Spacers for High‑Performance Ruddlesden–Popper Perovskite Solar Cells

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Nano-Micro Letters 2025年第2期17卷 314-357页

作者： Pengyun Liu Xuejin Li Tonghui Cai Wei Xing Naitao Yang hamidreza Arandiyan Zongping Shao Shaobin Wang Shaomin Liu School of Materials Science and Engineering State Key Laboratory of Heavy Oil ProcessingChina University of Petroleum(East China)Qingdao 266580People’s Republic of China School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255049People’s Republic of China Centre for Applied Materials and Industrial Chemistry(CAMIC) School of ScienceRMIT UniversityMelbourneVic 3000Australia WA School of Mines:Minerals Energy and Chemical Engineering(WASM‑MECE)Curtin UniversityPerthWA 6102Australia School of Chemical Engineering The University of AdelaideAdelaideSA 5005Australia School of Engineering Great Bay UniversityDongguan 523000People’s Republic of China

Layer-structured Ruddlesden–Popper(RP)perovskites(RPPs)with decent stability have captured the imagination of the photovoltaic research community and bring hope for boosting the development of perovskite solar cell(PSC)***,two-dimensional(2D)or quasi-2D RP PSCs are encountered with some challenges of the large exciton binding energy,blocked charge transport and poor film quality,which restrict their photovoltaic ***,these issues can be readily resolved by rationally designing spacer cations of *** review mainly focuses on how to design the molecular structures of organic spacers and aims to endow RPPs with outstanding photovoltaic *** firstly elucidated the important roles of organic spacers in impacting crystallization kinetics,charge transporting ability and stability of *** we brought three aspects to attention for designing organic ***,we presented the specific molecular structure design strategies for organic spacers of RPPs aiming to improve photovoltaic performance of RP *** proposed strategies in this review will provide new avenues to develop novel organic spacers for RPPs and advance the development of RPP photovoltaic technology for future applications.

关键词： Ruddlesden-Popper perovskites Low-dimensional perovskite solar cells Organic spacers Molecular structure Design strategies

Decentralized Voltage Control of Power Systems Using Multi-agent Systems

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Journal of Modern Power Systems and Clean Energy 2020年第2期8卷 249-259页

作者： hamidreza Shahbazi Farid Karbalaei the Department of Electrical Engineering Shahid Rajaee Teacher Training UniversityTehranIran the Faculty of Electrical Engineering Shahid Rajaee Teacher Training UniversityTehranIran

*** our proposed smart self-healing method,two types of control agents are defined,namely master and local,which are applied in two *** the first step,the power system returns to the normal state after fault *** after a fault detection in a power system,the system is divided into three subsystems using spectral graph *** is conducted based on reactive power flow in transmission *** each subsystem,a local control agent and a performance index(PI)are *** the PI of a subsystem exceeds its threshold limit,the local control agent uses the Sugeno fuzzy system to intelligently select and apply control *** the second step as performed by the master control agent,the power system is transformed to an optimal state by solving the optimization *** on a 39-bus New England reveal the effective performance of the proposed method.

关键词： Emergency voltage control partitioning multi-agent systems fuzzy systems

Josephson current versus potential strength of the interface in ferromagnetic superconductors

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Chinese Physics B 2014年第5期23卷 537-541页

作者： hamidreza Emamipour Department of Physics Ilam University

Based on the scattering theory, we calculate the Josephson current in a junction between two ferromagnetic super-conductors as a function of the interface potential z. We consider the ferromagnetic superconductor （FS） in three different Cooper pairing states： spin singlet s-wave pairing （SWP） state, spin triplet opposite spin pairing （OSP） state, and spin triplet equal spin pairing （ESP） state. We find that the critical Josephson current as a function of z shows clear differences among the SWP, OSP, and ESP states. The obtained results can be used as a useful tool for determining the pair symmetry of the ferromagnetic superconductors.

关键词： ferromagnetic superconductors spin singlet s-wave pairing state spin triplet opposite spin pairingstate spin triplet equal spin pairing state

Risk-Informed Model-Free Safe Control of Linear Parameter-Varying Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 1918-1932页

作者： Babak Esmaeili hamidreza Modares Department of Mechanical Engineering Michigan State UniversityEast LansingMI 48863 USA

This paper presents a risk-informed data-driven safe control design approach for a class of stochastic uncertain nonlinear discrete-time *** nonlinear system is modeled using linear parameter-varying(LPV)systems.A model-based probabilistic safe controller is first designed to guarantee probabilisticλ-contractivity(i.e.,stability and invariance)of the LPV system with respect to a given polyhedral safe *** obviate the requirement of knowing the LPV system model and to bypass identifying its open-loop model,its closed-loop data-based representation is provided in terms of state and scheduling data as well as a decision *** is shown that the variance of the closedloop system,as well as the probability of safety satisfaction,depends on the decision variable and the noise covariance.A minimum-variance direct data-driven gain-scheduling safe control design approach is presented next by designing the decision variable such that all possible closed-loop system realizations satisfy safety with the highest confidence *** minimum-variance approach is a control-oriented learning method since it minimizes the variance of the state of the closed-loop system with respect to the safe set,and thus minimizes the risk of safety *** the certainty-equivalent approach that results in a risk-neutral control design,the minimum-variance method leads to a risk-averse control *** is shown that the presented direct risk-averse learning approach requires weaker data richness conditions than existing indirect learning methods based on system identification and can lead to a lower risk of safety *** simulation examples along with an experimental validation on an autonomous vehicle are provided to show the effectiveness of the presented approach.

关键词： Data-driven control linear parameter-varying systems probabilistic control safe control

Deterministic and Stochastic Fixed-Time Stability of Discrete-time Autonomous Systems

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IEEE/CAA Journal of Automatica Sinica 2023年第4期10卷 945-956页

作者： Farzaneh Tatari hamidreza Modares Mechanical Engineering Department Michigan State UniversityMichigan 48824-1226 USA

This paper studies deterministic and stochastic fixedtime stability of autonomous nonlinear discrete-time(DT)*** conditions are first presented under which the fixed-time stability of deterministic DT systems is *** to systems under deterministic perturbations as well as stochastic noise are then *** the former,sensitivity to perturbations for fixed-time stable DT systems is analyzed,and it is shown that fixed-time attractiveness results from the presented Lyapunov *** the latter,sufficient Lyapunov conditions for fixed-time stability in probability of nonlinear stochastic DT systems are *** fixed upper bound of the settling-time function is derived for both fixed-time stable and fixed-time attractive systems,and a stochastic settling-time function fixed upper bound is derived for stochastic DT *** examples are given along with simulation results to verify the introduced results.

关键词： Discrete-time(DT)systems fixed-time stability nonlinear systems stochastic systems

Domestic PV System with Feedback Linearization-based Control Strategy for Module-level MPPT under Partial Shading Condition

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Journal of Modern Power Systems and Clean Energy 2021年第6期9卷 1530-1539页

作者： hamidreza Toodeji Shahram Aghaei Department of Electrical Engineering Yazd University

A partial shading condition can adversely affect the energy conversion efficiency of domestic photovoltaic(PV) systems. Connecting each PV module to a microinverter and performing module-level maximum power point tracking(MPPT)are proposed as promising solutions. In this paper, a feedback linearization-based control strategy is designed for the nonlinear system by a novel straightforward approach. The obtained nonlinear control law can independently govern each microinverter, providing module-level MPPT for PV modules without DC optimizer. Moreover, PV modules can be easily connected or disconnected due to the lug-and-play ability of the proposed controller. As a result, the proposed PV system can be easily maintained and extended even by non-expert users. Moreover,any module failure in the proposed PV system can be tolerated without impacts on the normal operation of other PV *** advantages of the proposed control strategy are verified by the simulation of a test PV system in MATLAB/Simulink under various partial shading conditions as well as adding or removing PV modules.

关键词： Domestic photovoltaic(PV)system microinverter power optimizer module-level maximum power point tracking(MPPT) plug-and-play feedback linearization-based control strategy

Relative Degree Structural Hole Centrality, CRD-SH: A New Centrality Measure in Complex Networks

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Journal of Systems Science & Complexity 2019年第5期32卷 1306-1323页

作者： SOTOODEH hamidreza FALAHRAD Mohammed Institute for Research in Fundamental Sciences(IPM) School of Computer ScienceTehranIran Qazvin Islamic Azad University Department of Computer EngineeringQazvinIran.

In order to assess influential nodes in complex networks, the authors propose a novel ranking method based on structural hole in combination with the degree ratio of a node and its neighbors. The proposed method is a response to the limitations of other proposed measures in this field. The structural hole gives a comprehensive attention of the information about the node topology in relation to its neighbors, whereas the degree ratio of nodes reflects its significance against the *** of the two aforementioned measures summarized in the structural hole leverage matrix demonstrates the importance of a node according to its position in the network structure. So a more accurate method for ranking influential nodes is established. The simulation results over different-scale networks(small networks with less than 30 nodes, medium networks with less than 150 nodes and large networks with more than 1000 nodes) suggest that the proposed method can rank important nodes more effectively and precisely in complex networks specifically in larger ones.

关键词： Centrality measures complex networks influential nodes structural hole leverage matrix

Zero-Bias Conductance versus Potential Strength of Interface in Ferromagnetic Superconductors

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Chinese Physics Letters 2012年第3期29卷 201-203页

作者： hamidreza Emamipour Jafar Emamipour Department of Physics Ilam UniversityIlamIran Young Researchers Club Ilam BranchIslamic Azad UniversityIlamIran

We study zero-bias conductance(ZBC)spectra of a normal-metal/insulator/singlet(and triplet)ferromagnetic superconductor as a function of potential strength of interface in the Blonder-Tinkham Klapwijk(BTK)theory *** consider possible pairing states including spin singlet s-wave pairing(SWP),spin triplet opposite spin pairing(OSP)and spin triplet equal spin pairing(ESP).It is found that ZBC as a function of potential strength of interface shows a clear difference between SWP,OSP and ESP *** results may serve as a useful tool for discriminating pairing states in ferromagnetic superconductors.

关键词： ferromagnetic singlet interface

Conflict-Aware Safe Reinforcement Learning:A Meta-Cognitive Learning Framework

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IEEE/CAA Journal of Automatica Sinica 2022年第3期9卷 466-481页

作者： Majid Mazouchi Subramanya Nageshrao hamidreza Modares Michigan State University East LansingMI 48824 USA Ford Research and Innovation Center Ford Motor CompanyPalo AltoCA 94304 USA IEEE

In this paper,a data-driven conflict-aware safe reinforcement learning(CAS-RL)algorithm is presented for control of autonomous *** safe RL results with predefined performance functions and safe sets can only provide safety and performance guarantees for a single environment or *** contrast,the presented CAS-RL algorithm provides safety and performance guarantees across a variety of circumstances that the system might *** is achieved by utilizing a bilevel learning control architecture:A higher metacognitive layer leverages a data-driven receding-horizon attentional controller(RHAC)to adapt relative attention to different system’s safety and performance requirements,and,a lower-layer RL controller designs control actuation signals for the *** presented RHAC makes its meta decisions based on the reaction curve of the lower-layer RL controller using a metamodel or *** specifically,it leverages a prediction meta-model(PMM)which spans the space of all future meta trajectories using a given finite number of past meta *** will adapt the system’s aspiration towards performance metrics(e.g.,performance weights)as well as safety boundaries to resolve conflicts that arise as mission scenarios *** will guarantee safety and feasibility(i.e.,performance boundness)of the lower-layer RL-based control *** is shown that the interplay between the RHAC and the lower-layer RL controller is a bilevel optimization problem for which the leader(RHAC)operates at a lower rate than the follower(RL-based controller)and its solution guarantees feasibility and safety of the control *** effectiveness of the proposed framework is verified through a simulation example.

关键词： Optimal control receding-horizon attentionalcontroller(RHAC) reinforcement learning(RL)