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Collision Resolution in RFID Systems Using Antenna Arrays and Mix Source Separation

IEEE COMMUNICATIONS LETTERS 2025年第5期29卷 1122-1125页

作者： Siala, Mohamed Sellami, Noura Univ Carthage Higher Sch Commun Tunis SUP COM Mediatron Lab Tunis 2083 Tunisia Univ Sfax Natl Sch Engn Sfax ENIS LETI Lab Sfax 3038 Tunisia

In this letter, we propose an efficient mix source separation (MSS) algorithm for collision resolution in radio frequency identification (RFID) systems equipped with an antenna array at the reader. We first introduce an approach that exploits the zero constant modulus (ZCM) criterion to separate colliding tags through gradient descent, without using pilot symbols. We show that the ZCM characteristic, considered alone, in the design of the objective function can lead to significant ambiguities in the determination of the beamformers used in the recovery of tag messages. To address this limitation, we propose a more sophisticated approach, relying on a hybrid objective function, incorporating a new ambiguity-raising criterion in addition to the ZCM criterion.

关键词： Radiofrequency identification Linear programming Vectors Symbols Signal processing algorithms Receiving antennas Fluctuations Encoding Blind source separation Antenna arrays Mix source separation (MSS) gradient descent algorithm RFID zero constant modulus criterion

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Estimation and analysis of vegetation parameters for the water cloud model

River

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River 2024年第4期3卷 399-407页

作者： Xiangdong Qin Zhiguo Pang Jingxuan Lu Department of Drought Mitigation and Policy Research Research Center on Flood and Drought Disaster Reduction of the Ministry of Water ResourcesChina Institute of Hydraulic and Hydropower ResearchBeijingChina State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijingChina

The Water Cloud Model(WCM)plays a crucial role in active microwave soil moisture inversion *** parameters are important factors affecting the accuracy of WCM simulation,but the current evaluation of empirical parameters only considers the forward simulation process,and insufficient consideration is given to the model inversion *** study proposes a new estimation method for vegetation parameters in the WCM by combining the soil backscattering model and the objective *** effectiveness of the method is then verified using measured ***,this study also analyzes the factors influencing the evaluation of vegetation parameters in the WCM,resulting in the following ***,blindly utilizing vegetation parameters recommended by previous model studies is not *** ensure the accuracy of the simulation,it is necessary to adjust the vegetation parameters ***,to ensure the ability of the WCM solving both forward and inverse problems,it is advisable to consider both soil backscatter and surface backscatter simulations in the construction of the cost ***,soil backscatter simulations have an impact on the solution of vegetation parameters,and more accurate soil scattering models provide a better representation of the modeled *** study presents a dependable method for resolving the vegetation parameters of the WCM,thereby offering a valuable reference for the application of the model in surface parameter inversion research.

关键词： backscattering coefficient gradient descent algorithm objective function soil moisture water cloud model

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Filtering-Based Accelerated Estimation Approach for Generalized Time-Varying Systems With Disturbances and Colored Noises

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II-EXPRESS BRIEFS 2023年第1期70卷 206-210页

作者： Ji, Yan Jiang, Anning Qingdao Univ Sci & Technol Coll Automat & Elect Engn Qingdao 266061 Peoples R China

This brief studies the parameter estimation problem of a generalized time-varying system by using a novel gradient descent algorithm. The time-varying parameters are estimated by the accelerating gradient descent algorithm under considering the measurable disturbance factors. The proposed algorithm increases the convergence rate by adding a momentum term to the correction of the parameter updated estimates. In addition, a data filter is introduced to filter the input and output data, so as to eliminate the interference of colored noise to the accuracy of parameter estimation. A numerical example shows the effectiveness of the proposed algorithm.

关键词： Generalized time-varying system gradient descent algorithm parameter estimation

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A MINLP model for the layout design of subsea oil gathering- transportation system in deep water oil field considering avoidance of subsea obstacles and pipe intersections

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OCEAN ENGINEERING 2023年第1期277卷

作者： Hong, Cheng Wang, Yuxi Estefen, Segen F. Ningbo Univ Fac Maritime & Transportat Ningbo 315211 Peoples R China Univ Fed Rio de Janeiro Ocean Engn Dept COPPE BR-21941972 Rio De Janeiro Brazil State key Lab Petr Pollut Control Beijing 102206 Peoples R China CNPC Res Inst Safety & Environm Technol Beijing 102206 Peoples R China

This paper focuses on the layout design of subsea oil gathering-transportation system in deep water oil field. In such a system, subsea manifolds are applied to gather and transport the produced fluids from subsea wells to floating processing terminals. A mixed integer nonlinear programming (MINLP) model is proposed, constrained by a series of operation and production requirements, aiming to minimize the total layout cost. Through the model, the pipe line network topology structure which reflects the allocations among the subsea wells, manifolds and processing terminals, the routes of pipes, as well as the size of the facilities could all be figured out. Two key contributions are made through this work. First, avoiding pipe intersections and subsea obstacles are integrated simultaneously, making the proposed model closer to practical situations. Second, a decomposition strategy based on Delaunay triangulation and gradient descent is constructed, achieving high quality initial solution and stable iteration process. The results of case studies indicate the validity, feasibility and stability of the proposed model and the solution method. Besides, the effect of manifold numbers on the layout optimization result is analyzed through the model, indicating its flexibility in the layout design analysis.

关键词： Subsea oil gathering-transportation Layout design Mixed integer nonlinear programming Delaunay triangulation gradient descent algorithm

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A New Method for the Design of Interval Type-3 Fuzzy Logic Systems With Uncertain Type-2 Non-Singleton Inputs (IT3 NSFLS-2): A Case Study in a Hot Strip Mill

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IEEE ACCESS 2023年 11卷 44065-44081页

作者： Mendez, G. M. Lopez-Juarez, Ismael Montes-Dorantes, P. N. Garcia, M. A. Inst Tecnol Nacl Mexico Elect & Elect Engn Dept Campus Nuevo Leon Guadalupe 67170 Nuevo Leon Mexico CINVESTAV IPN Saltillo Robot & Adv Mfg Dept Ramos Arizpe Coahuila Mexico Univ Autonoma Nuevo Leon Fac Phys & Math Sci San Nicolas De Los Garza 66455 Nuevo Leon Mexico

This paper presents a new method for the construction and training of interval type-3 fuzzy logic systems whose inputs are uncertain type-2 non-singleton numbers (IT3 NSFLS-2). The proposed methodology is divided in two processes: 1) The novel construction of the structure of the IT3 NSFLS-2 systems based on: a) The level-alpha-0 of the interval type-2 fuzzy logic system (IT2-alpha-0 FLS), and on b) The secondary membership function using Gaussian modeling to construct each rule of the alpha-k fuzzy rule base (FRB), the firing intervals of the antecedent and the centroids of the consequent, and 2) The training methodology based on gradient descent algorithm to train the antecedent and consequent parameters of the alpha-0 FRB. The primary membership functions (MF) of the antecedents of the IT3 NSFLS-2 system are modeled as Gaussians with uncertain means and with common standard deviation. The proposal was applied and tested with the prediction of a transfer bar's surface temperature in an industrial hot strip mill facility located in Monterrey Mexico. The modeling results show that the proposal supports the stability required by this critical process and shows the best performance when compared with similar methods.

关键词： Fuzzy logic Mathematical models Kalman filters Fuzzy systems Estimation Adaptation models Predictive models Temperature measurement General type-2 fuzzy systems gradient descent algorithm hot strip mill interval type-2 fuzzy systems interval type-3 fuzzy systems temperature prediction type-2 non-singleton inputs

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A data-driven method for probabilistic response of vibro-impact system with bilateral barriers

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NONLINEAR DYNAMICS 2023年第5期111卷 4205-4219页

作者： Sun, Wenqing Feng, Jinqian Su, Jin Guo, Qin Xian Polytech Univ Sch Sci Xian 710048 Shaanxi Peoples R China

In this paper, a data-driven method is proposed to approximate the probability density function (PDF) of the response for the vibro-impact system with bilateral barriers. Non-smooth property is a challenge in random dynamical system, resulting in complex dynamics, such as discontinuous-induced singularity, grazing and chattering. The vibro-impact system is generally described as a hybrid form with discrete mapping and continuous differential equation. A non-smooth variable transformation is employed to rewritten this hybrid form to an equivalent piecewise version. For the obtained equivalent system, the Gaussian mixture model is proposed to approach the PDF governed by the Fokker-Planck-Kolmogorov (FPK) equation. The proposed algorithm can accurately simulate the PDF of the vibro-impact system with varied restitution coefficients within the theoretical difference allowed by the non-smooth variable transformation method. Taking account of the symmetry of the inverse transformation, the stationary PDF and moments of responses for the original system are obtained. Additionally, two examples are provided to demonstrate the efficiency and correctness of the proposed method.

关键词： Vibro-impact system Probabilistic response Moment estimation Gaussian mixture model gradient descent algorithm

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Optimization of gradient descent Parameters in Attitude Estimation algorithms

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SENSORS 2023年第4期23卷 2298-2298页

作者： Sever, Karla Golusin, Leonardo Max Loncar, Josip Univ Zagreb Fac Elect Engn & Comp Dept Commun & Space Technol Unska 3 Zagreb 10000 Croatia

Attitude estimation methods provide modern consumer, industrial, and space systems with an estimate of a body orientation based on noisy sensor measurements. The gradient descent algorithm is one of the most recent methods for optimal attitude estimation, whose iterative nature demands adequate adjustment of the algorithm parameters, which is often overlooked in the literature. Here, we present the effects of the step size, the maximum number of iterations, and the initial quaternion, as well as different propagation methods on the quality of the estimation in noiseless and noisy conditions. A novel figure of merit and termination criterion that defines the algorithm's accuracy is proposed. Furthermore, the guidelines for selecting the optimal set of parameters in order to achieve the highest accuracy of the estimate using the fewest iterations are proposed and verified in simulations and experimentally based on the measurements acquired from an in-house developed model of a satellite attitude determination and control system. The proposed attitude estimation method based on the gradient descent algorithm and complementary filter automatically adjusts the number of iterations with the average below 0.5, reducing the demand on the processing power and energy consumption and causing it to be suitable for low-power applications.

关键词： attitude estimation rotational quaternion Euler angles gradient descent algorithm complementary filter optimization

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Joint variable and variable projection algorithms for separable nonlinear models using Aitken acceleration technique

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INTERNATIONAL JOURNAL OF MODELLING IDENTIFICATION AND CONTROL 2023年第3期42卷 202-210页

作者： Cheng, Lianyuan Chen, Jing Rong, Yingjiao Jiangnan Univ Sch Sci Wuxi 214122 Peoples R China Sci & Technol Near Surface Detect Lab Wuxi Peoples R China

This paper proposes a joint variable-based gradient descent algorithm (Joint-GD) and a variable projection (VP)-based gradient descent algorithm (VP-GD) for separable nonlinear models. The VP algorithm takes advantage of the separability property of variables to reduce the dimensionality of the parameters, which makes the convergence rates faster. In order to speed up the convergence of the gradient descent algorithm, the Aitken acceleration technique is introduced in the algorithms, which is second-order convergent. Moreover, the Aitken-based methods are robust to the step-size, therefore they can be widely used in engineering practices. The numerical simulation shows the effectiveness of the proposed algorithms.

关键词： variable projection algorithm joint variable algorithm gradient descent algorithm separable nonlinear model Aitken acceleration technique

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Optimal Control of Integrated Losses in Dual Active Bridge DC-DC Converters Under Extended Modulation

Optimal Control of Integrated Losses in Dual Active Bridge D...

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International Conference on Wireless Power Transfer (ICWPT)

作者： Hao, Rui Wang, Xiaolan Wei, Tengfei Wang, Jiarui Wang, Lixin Yue, Meng Li, Zhaohui Lanzhou Univ Technol Univ Lanzhou 730000 Peoples R China

ISBN: (纸本)9789819708673;9789819708659;9789819708642

In order to reduce the overall power loss of the bidirectional active bridge (DAB) converter and optimise its dynamic characteristics;this paper proposes a hybrid optimal control strategy based on the output voltage model predictive control of extended phase-shift modulation and gradient descent algorithm. The state space model of the DAB converter is established by analysing its operating modes under extended phase shift;the switching tube and transformer losses of the DAB converter are investigated to obtain the integrated loss model of the DAB converter;and the output voltage model predictive control is combined with the gradient descent algorithm to optimise the target power loss. Simulation results show that compared with the traditional PI control, the transfer efficiency of the method proposed in this paper is improved by about 3.7%;the dynamic recovery time is reduced by about 80% and the output voltage fluctuation is reduced by about 76% when the input voltage and the load are perturbed, which verifies the effectiveness of the control strategy.

关键词： Extended Phase Shift Modulation Integrated loss optimization gradient descent algorithm

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A CONTROL-ORIENTED HYBRID MODEL FOR NUCLEAR REACTORS BASED ON NEURAL NETWORK 31

A CONTROL-ORIENTED HYBRID MODEL FOR NUCLEAR REACTORS BASED O...

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31st International Conference on Nuclear Engineering (ICONE) - 24/7 Clean Nuclear Energy - Solution for Global Warming

作者： Zhu, Ze Liang, Wenlong Ye, Baiqing Jiang, Qingfeng Wang, Pengfei Xi An Jiao Tong Univ Xian Shaanxi Peoples R China

ISBN: (纸本)9780791888216

Accurate modeling is the basis for analyzing the dynamic response characteristics of the model. However, due to the complexity and time-varying nature of the internal mechanisms of the reactor, it is inevitable that inaccurate model parameters will be used in the modeling process. These will lead to discrepancies between the modeled mechanisms and the actual reactor. In this paper, the difference is evaluated and shortened by means of neural network hybrid modeling. Based on the MATLAB/Simulink simulation platform, this paper firstly obtains the parameters that have the greatest influence on the linear model through sensitivity analysis and takes them as the object of neural network correction, then obtains the data required for offline training of neural network according to the mechanism model, linear model and the deviation of the two under different working condition levels, retains the neural network weights and thresholds obtained from the offline training, and finally utilizes the gradient descent algorithm to update the neural network weights and thresholds in real time in order to achieve the online calibration of the linear model. The final results show that the hybrid model can effectively reduce the steady-state deviation between the two models, which indicates that the hybrid modeling can effectively improve the accuracy of the established model and provide a solid foundation for the subsequent design of the control system based on the linear model.

关键词： Hybrid modeling Mechanism model Linear model Neural network gradient descent algorithm

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