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Deep Reinforcement Learning Based Joint Downlink Beamforming and RIS Configuration in RIS-aided MU-MISO systems Under Hardware Impairments and Imperfect CSI

arXiv

引用

arXiv 2022年

作者： Saglam, Baturay Gurgunoglu, Doga Kozat, Suleyman S. Department of Electrical and Electronics Engineering Bilkent University Ankara06800 Turkey Division of Decision and Control Systems KTH Royal Institute of Technology Stockholm100 44 Sweden

We introduce a novel deep reinforcement learning (DRL) approach to jointly optimize transmit beamforming and reconfigurable intelligent surface (RIS) phase shifts in a multiuser multiple input single output (MU-MISO) system to maximize the sum downlink rate under the phase-dependent reflection amplitude model. Our approach addresses the challenge of imperfect channel state information (CSI) and hardware impairments by considering a practical RIS amplitude model. We compare the performance of our approach against a vanilla DRL agent in two scenarios: perfect CSI and phase-dependent RIS amplitudes, and mismatched CSI and ideal RIS reflections. The results demonstrate that the proposed framework significantly outperforms the vanilla DRL agent under mismatch and approaches the golden standard. Our contributions include modifications to the DRL approach to address the joint design of transmit beamforming and phase shifts and the phase-dependent amplitude model. To the best of our knowledge, our method is the first DRL-based approach for the phase-dependent reflection amplitude model in RIS-aided MU-MISO systems. Our findings in this study highlight the potential of our approach as a promising solution to overcome hardware impairments in RIS-aided wireless communication systems. Copyright © 2022, The Authors. All rights reserved.

关键词： Reinforcement learning

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Effects of calcination temperature on physicochemical property and activity of CuSO4/TiO2 ammonia-selective catalytic reduction catalysts

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Journal of Environmental Sciences 2020年第5期32卷 237-245页

作者： Yanke Yu Jiali Zhang Changwei Chen Chi He Jifa Miao Huirong Li Jinsheng Chen Department of Environmental Science and Engineering School of Energy and Power EngineeringXi’an Jiaotong UniversityXi'an 710049China Department of Chemical Engineering Columbia UniversityNew York 10027USA College of Geology and Environment Xi’an University of Science and TechnologyXi’an 710054China National Engineering Laboratory for VOCs Pollution Control Material and Technology University of Chinese Academy of SciencesBeijing 101408China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

CuSO4/TiO2 catalysts with high catalytic activity and excellent resistant to SO2 and H2 O,were thought to be promising catalysts used in Selective catalytic reduction of nitrogen oxides by *** performance of catalysts is largely affected by calcination ***,effects of calcination temperature on physicochemical property and catalytic activity of CuSO4/TiO2 catalysts were investigated in *** samples calcined at different temperatures were prepared first and then physicochemical properties of the catalyst were characterized by N2 adsorption-desorption,X-ray diffraction,thermogravimetric analysis,Raman spectra,Fourier-transform infrared spectroscopy,X-ray photoelectron spectroscopy,temperature-pro grammed desorption of NH3,temperature-programmed reduction of H2 and in situ diffuse reflectance infrared Fourier transform *** revealed that high calcination temperature had three main effects on the ***,sintering and anatase transform into rutile with increase of calcination temperature,causing a decrement of specific surface ***,decomposition of CuSO4 under higher calcination temperature,resulting in disappears of Br(?)nsted acid sites(S-OH),which had an adverse effect on surface ***,CuO from the decomposition of CuSO4 changed surface reducibility of the catalyst and favored the process of NH3 oxidation to nitrogen oxides(NOx).Thus,catalytic activity of the catalyst calcined under high temperatures(≥600℃)decreased largely.

关键词： Calcination temperature Sulfate catalyst Selective catalytic reduction of nitrogen oxides by NH3 Surface acidity NH3 oxidation

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Constrained Optimization with Decision-Dependent Distributions

arXiv

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arXiv 2023年

作者： Wang, Zifan Liu, Changxin Parisini, Thomas Zavlanos, Michael M. Johansson, Karl H. Division of Decision and Control Systems School of Electrical Engineering and Computer Science KTH Royal Institute of Technology Sweden Digital Futures StockholmSE-10044 Sweden The Department of Electrical and Electronic Engineering Imperial College London LondonSW7 2AZ United Kingdom The Department of Engineering and Architecture University of Trieste Trieste34127 Italy The KIOS Research and Innovation Center of Excellence University of Cyprus NicosiaCY-1678 Cyprus The Department of Mechanical Engineering and Materials Science Duke University DurhamNC United States

In this paper we deal with stochastic optimization problems where the data distributions change in response to the decision variables. Traditionally, the study of optimization problems with decision-dependent distributions has assumed either the absence of constraints or fixed constraints. This work considers a more general setting where the constraints can also dynamically adjust in response to changes in the decision variables. Specifically, we consider linear constraints and analyze the effect of decision-dependent distributions in both the objective function and constraints. Firstly, we establish a sufficient condition for the existence of a constrained equilibrium point, at which the distributions remain invariant under retraining. Morevoer, we propose and analyze two algorithms: repeated constrained optimization and repeated dual ascent. For each algorithm, we provide sufficient conditions for convergence to the constrained equilibrium point. Furthermore, we explore the relationship between the equilibrium point and the optimal point for the constrained decision-dependent optimization problem. Notably, our results encompass previous findings as special cases when the constraints remain fixed. To show the effectiveness of our theoretical analysis, we provide numerical experiments on both a market problem and a dynamic pricing problem for parking based on real-world data. Copyright © 2023, The Authors. All rights reserved.

关键词： Constrained optimization

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NARX Identification using Derivative-Based Regularized Neural Networks

NARX Identification using Derivative-Based Regularized Neura...

引用

IEEE Conference on Decision and control

作者： L.H. Peeters G.I. Beintema M. Forgione M. Schoukens Department of Electrical Engineering Control Systems group Eindhoven University of Technology The Netherlands IDSIA Dalle Molle Institute for Artificial Intelligence USI-SUPSI Lugano-Viganello Switzerland

ISBN: (数字)9781665467612

ISBN: (纸本)9781665467629

This work presents a novel regularization method for the identification of Nonlinear Autoregressive eXogenous (NARX) models. The regularization method promotes the exponential decay of the influence of past input samples on the current model output. This is done by penalizing the sensitivity of the NARX model simulated output with respect to the past inputs. This promotes the stability of the estimated models and improves the obtained model quality. The effectiveness of the approach is demonstrated through a simulation example, where a neural network NARX model is identified with this novel method. Moreover, it is shown that the proposed regularization approach improves the model accuracy in terms of simulation error performance compared to that of other regularization methods and model classes.

关键词： Training Sensitivity Neural networks Estimation Stability analysis

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Three-Dimensional Seismic Response in Complex Site Conditions: A New Approach Based on an Auxiliary-Model Method

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Journal of Earth Science 2021年第5期32卷 1152-1165页

作者： Xiaolong Zhang Xiaobo Peng Xiaojun Li Zhenghua Zhou Chong Xu Zhan Dou Bideng Liu National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China Jiangsu Earthquake Agency Nanjing 210014China College of Architecture and Civil Engineering Beijing University of TechnologyBeijing 100124China College of Transportation Science of Engineerings Nanjing Tech University Nanjing 210009China Key Laboratory of Compound and Chained Natural Hazards Dynamics(Under Construction) Ministry of Emergency Management of ChinaBeijing 100085China Department of Safety Engineering College of Mechanical and Electrical EngineeringBeijing University of Chemical TechnologyBeijing 100029China State Environmental Protection Engineering Center for City Noise and Vibration Control Beijing Municipal Institute of Labor ProtectionBeijing 100054China

In this paper, an auxiliary-model method is proposed for calculating equivalent input seismic loads in research of ground motions. This method can be used to investigate the local effect of 3 D complex sites subjected to obliquely incident SV and P waves. Using this method, we build a fictitious auxiliary model along the normal direction of the boundary of the area of interest, with the model’s localized geological features remaining the same along a vector normal to this boundary. This model is divided into five independent auxiliary models, which are then dynamically analyzed to obtain the equivalent input seismic loads. Unlike traditional methods, in this new technique, the mechanical behavior of the auxiliary model can be nonlinear, and its geometry can be arbitrary. In addition, a detailed description of the steps to calculate the equivalent input seismic loads is given. Numerical examples of incident plane-wave propagation at uniform sites with local features validate the effectiveness of this method. It is also applicable to elastic and non-elastic problems.

关键词： seismic-wave input topography effect oblique incidence equivalent input seismic load free field motion

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Quantitative evaluation of nanoparticles internalization in living cells by holographic microscopy 6

Quantitative evaluation of nanoparticles internalization in ...

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Optical Methods for Inspection, Characterization, and Imaging of Biomaterials VI 2023

作者： Pirone, Daniele Mugnano, Martina Memmolo, Pasquale Merola, Francesco Lama, Giuseppe Cesare Castaldo, Rachele Miccio, Lisa Bianco, Vittorio Grilli, Simonetta Ferraro, Pietro CNR-ISASI Institute of Applied Sciences and Intelligent Systems "E. Caianiello" Via Campi Flegrei 34 Pozzuoli Napoli80078 Italy DICMaPI Department of Chemical Materials and Production Engineering University of Naples "Federico II" Piazzale Tecchio 80 Napoli80125 Italy CEINGE—Biotecnologie Avanzate Napoli Italy CNR-IPCB Institute of Polymers Composites and Biomaterials Via Campi Flegrei 34 Pozzuoli Napoli80078 Italy

ISBN: (数字)9781510664548

ISBN: (纸本)9781510664531

Nanoparticles (NPs) internalization process in living cells has large perspectives for drug-delivery applications, but the efficient cellular uptake is still a remarkable challenge. Recently, it has been demonstrated that nanographene oxide (nGO) particles are massively internalized into the cell cytoplasm, opening the way of using graphene family materials for the above goal. Internalized nGO can interact with intracellular elements, thus modifying the life cycle pathways. Therefore, there is a great interest in studying the cellular uptake process and the volumetric distribution of nGO inside the cells. He we report on the use of holographic microscopy for quantitatively evaluating the nGO cellular uptake in both 2D and 3D. In particular, quantitative phase images of adherent cells with internalized nGO are used to measure the cells biovolume variation in time, while tomographic reconstructions of cells in flow cytometry condition are exploited to visualize in 3D the distribution of nGO within the cells cytoplasm. The study is conducted on NIH-3T3 cells to analyze the effects of nGO in vitro and monitoring the cell culture was for several hours to allow a time-lapse of nGO uptake. © 2023 SPIE.

关键词： Cells

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Mn, N co-doped carbon nanospheres for efficient capture of uranium (VI) via capacitive deionization

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Chemosphere 2023年 342卷 140190页

作者： Jin, Meiyue Huang, Xinhua Wang, Zhirou Chan, Vincent Hu, Jinsong Wu, Ai Hu, Guangzhi School of Materials Science and Engineering Anhui University of Science and Technology Huainan232001 China Department of Biomedical Engineering Khalifa University of Science and Technology Abu Dhabi United Arab Emirates School of Chemical Engineering Anhui University of Science and Technology Huainan232001 China Institute of Energy Hefei Comprehensive National Science Center Hefei230031 China Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental Science Yunnan University Kunming650504 China

Heteroatom doping, involving the introduction of atoms with distinct electronegativity into carbon materials, has emerged as an effective approach to optimize their charge distribution. In this study, we designed a strategy to synthesize in-situ Mn, N co-doped carbon nanospheres (Mn-NC) through the polycondensation of 2,6-diaminopyridine and formaldehyde in synchronization with Mn2+ chelation to form Mn-polytriazine precursor, followed by calcination to form carbonaceous solid. Then Mn-NC was fabricated into a capacitive deionization (CDI) electrode for the selective removal of uranium ions (U (VI)), which is commonly found in radioactive water. Interestingly, Mn-NC exhibited good selectivity for UO22+ capture with a demonstrated adsorption capacity of approximately 194 mg/g @1.8 V. The systematic analysis of the adsorption mechanism of UO22+ revealed that N dopants within Mn-NC can coordinate with the U (VI) ions, thereby facilitating the removal process. Our study presents a straightforward and convenient strategy for removing UO22+ ions by harnessing the coordination effect, eliminating the requirement for pore size control. © 2023 Elsevier Ltd

关键词： Ions

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Frequency multiplexed photothermal correlation tomography for non-destructive evaluation of manufactured materials

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International Journal of Extreme Manufacturing 2025年第3期 538-552页

作者： Pengfei Zhu Rongbang Wang Koneswaran Sivagurunathan Stefano Sfarra Fabrizio Sarasini Clemente Ibarra-Castanedo Xavier Maldague Hai Zhang Andreas Mandelis Department of Electrical and Computer Engineering Computer Vision and Systems Laboratory(CVSL)Laval University Centre for Composite Materials and Structures (CCMS) Harbin Institute of Technology Center for Advanced Diffusion-Wave and Photoacoustic Technologies (CADIPT) and Institute for Advanced Non-Destructive and Non-Invasive Diagnostic Technologies (IANDIT) Department of Mechanical and Industrial EngineeringUniversity of Toronto Department of Industrial and Information Engineering and Economics (DIIIE) University of L'Aquila Department of Chemical Engineering Materials Environment&UDR INSTM Sapienza University of Rome

Infrared thermography has been widely applied in real industrial inspection of aerospace,energy management systems,engines,and electric ***,two-dimensional imaging modality limits its ***,a technique named frequency multiplexed photothermal correlation tomography (FM-PCT) was developed to enable non-destructive and contactless cross-sectional imaging for manufactured material evaluation and *** combining advantages of photothermal tomography and pulsed thermography,FM-PCT facilitates the generation of three-dimensional thermal images through temporal superposition(stacking) of two-dimensional images from sequential subsurface ***-PCT image processing involves pulsed excitation signals to which frequency delay and matched filtering techniques are *** features of FM-PCT are high-resolution three-dimensional tomographic imaging under low camera frame-rate conditions with self-correcting capability for diffusion (blurring) correction of subsurface images due to cross-correlation processing of individual frequencies in the Fourier decomposition spectrum of the excitation ***,FM-PCT extends truncated-correlation photothermal coherence tomography from chirp and pulsed signals to more general linear heating ***-in thermography and x-ray computed tomography validation demonstrate that 3D FM-PCT imaging accurately reveals subsurface discontinuities/defects in solids despite the diffusive nature of thermal-wave imaging.

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NARX Identification using Derivative-Based Regularized Neural Networks

arXiv

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arXiv 2022年

作者： Peeters, L.H. Beintema, G.I. Forgione, M. Schoukens, Maarten Control Systems Group Department of Electrical Engineering Eindhoven University of Technology Netherlands IDSIA Dalle Molle Institute for Artificial Intelligence USI-SUPSI Lugano-Viganello Switzerland

关键词： Machine learning

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Privacy Preservation by Intermittent Transmission in Cooperative LQG control systems

Privacy Preservation by Intermittent Transmission in Coopera...

引用

Asian control Conference

作者： Wenhao Lin Yuqing Ni Wen Yang Chao Yang Department of Automation Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of Education East China University of Science and Technology Shanghai China Key Laboratory of Advanced Process Control for Light Industry (Ministry of Education) School of Internet of Things Engineering Jiangnan University Wuxi China

ISBN: (数字)9789887581598

ISBN: (纸本)9798331540845

In this paper, we study a cooperative linear quadratic Gaussian (LQG) control system with a single user and a server. In this system, the user runs a process and employs the server to meet the needs of computation. However, the user regards its state trajectories as privacy. Therefore, we propose a privacy scheme, in which the user sends data to the server intermittently. By this scheme, the server's received information of the user is reduced, and consequently the user's privacy is preserved. In this paper, we consider a periodic transmission scheme. We analyze the performance of privacy preservation and LQG control of different transmission periods. Under the given threshold of the control performance loss, a trade-off optimization problem is proposed. Finally, we give the solution to the optimization problem.

关键词： Measurement Privacy Data privacy Networked control systems Trajectory Servers Optimization

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