Secure resource allocation in hybrid energy-harvesting relay and full-duplex receiver by Wei WANG, Xinrui LI, Liuguo YIN, Guoan ZHANG, Shibing ZHANG

“…Taking into account the wireless physical layer security in energy-constrained relaying systems,a secure resource allocation scheme was proposed under simultaneous wireless information and power transfer (SWIPT) protocol.The utility optimization problem was considered aiming to maximize the secrecy rate by jointly optimizing the power splitting (PS) ratio and the transmit powers under the constraint of the transmit powers of the nodes and the harvested energy of the relay.The objective problem,which is non-convex,was decoupled into two subproblems.One was to optimize the PS ratio,another was to optimize the transmit powers.The optimal solution of the subproblems can be obtained in the closed-form.Then,the suboptimal solution is obtained with the proposed convergent iterative algorithm.Simulation results show the effects of artificial noise signal,residual self-interference signal,transmit power of nodes,amplification factor of relay and other factors on the security performance.Compared with the traditional gradient descent algorithm,the proposed algorithm can reduce more than 80% of the computational load,while the algorithm has the slightly better performance.…”
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Improved artificial fish-swarm algorithm based on adaptive vision for solving the shortest path problem by Xian-min MA, IUN L

“…To solve basic artificial fish-swarm algorithm(AFSA)’s drawbacks of low convergence rate in the latter stage,a large amount of computation and easiness of trapping in local optimal solution,caused by the constant vision of the artificial fish,an improved artificial fish-swarm algorithm based on adaptive vision(AVAFSA) was proposed.The improved algorithm only adjusted the vision of the preying behavior of artificial fish to make the vision gradually decrease with the increase of the number of iterations of the algorithm.When the value became less than half the initial value,it made the value be equal to half the initial value.The proposed improved artificial fish swarm algorithm was applied to the static shortest path problem based on road network to provide customers with the best path.Simulation results depict the improved algorithm has higher convergence rate,a smaller amount of calculation,and is more accurate and stable than the basic AFSA and ant colony optimization(ACO).…”
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MULTI-OBJECTIVE RELIABILITY OPTIMIZATION DESIGN OF PLANETARY GEAR TRANSMISSION BASED ON IMPROVED PARTICLE SWARM ALGORITHM by WANG ChunHua, GUO Yue, JIANG ZongShuai

“…The algorithm set the penalty function as a multi-level penalty function and the penalty coefficient could be adjusted with the iterative process. The reliability and others were taken as the constraint conditions, the volume, the contact ratio and the transmission efficiency as the objective functions. …”
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Review on Surface Polishing Methods of Optical Parts by Mingli Xie, Yipeng Pan, Zijun An, Shijun Huang, Min Dong

“…Considering the development of optical part surface polishing technology in recent years, this study analyzes the principle and development process of typical processing methods represented by each kind of polishing technology, expounds the specific research progress of optical part surface polishing technology, including the iterative renewal of traditional technologies and the research development of new technologies, and gives examples for typical applications. …”
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Research on the application of weighted-Laguerre-FDTD method with “unidirectional explicit” matrix in cylindrical structure by Dawei ZHU, Hailin CHEN, Zhongwen SHEN, Xiuling JIA, Zhen LI

“…To solve the shortcomings of FDTD algorithm in electromagnetic wave propagation in communication applications.A FDTD algorithm under “unidirectional explicit” matrix was constructed and applied to cylindrical structure.Firstly, a new coefficient matrix was established by the ideology of WCS and WLP.Secondly, the perturbation terms were introduced to form the initial value and iterative equations.Finally, the fields on the z axis were treated in special way.Numerical examples prove that the proposed algorithm is superior to the WCS-FDTD and WLP-FDTD in electromagnetic wave propagation.The best improvement efficiency is 83%, accuracy is 88%, and memory consumption is reduced by 44%.Meanwhile, comparing with the conventional FDTD algorithm, it can improve the efficiency of 7 time steps size and reduce the memory consumption by 53% without losing accuracy.Moreover, under the boundary truncation of the PML, the proposed algorithm also shows good electromagnetic wave energy absorption performance, which can reach below -60 dB.…”
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AXIAL TENSILE STRENGTH ANALYSIS OF UNBONDED FLEXIBLE PIPE CONTAINING COMPOSITE TENSILE ARMORS by MA JinSheng, DU FaXi, LUO Dan

“…As offshore oil industry moves into ultra-deep water,replacing the steel tensile armors of unbonded flexible pipe with composite is becoming a scheme that can effectively reduce weight and provide better mechanical properties.The anisotropic parameters of composite are obtained by meso-mechanical method,then a model of axisymmetric structure response for composite flexible pipe with composite armored layer is established,which is based on both thick-wall cylinder theory and the differential equation of curved beam,and also the algorithm of cyclic iterative is combined.Failure models of different type of flexible pipes are obtained,and iso-strength method is used for composite armored pipe.A case study shows that composite armors can effectively enhance the tensile strength of unbonded flexible pipe while effectively reduce the overall weight.Results state that volume fraction,elastic modulus and strength of fiber are the important parameters which affect the axial stiffness and tensile strength of unbonded flexible pipe.…”
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Segment search for local extremums of images based on the analysis of brightness of adjacent homogeneous areas by V. Yu. Tsviatkou, Anh Tuan Nguyen

“…Their differences from well-known models are: consideration of homogeneous areas, which are formed by non-strict extremes and are local maxima or minima in relation to adjacent areas; elimination of iterative processing of non-extreme pixels; assigning the numbers to local extremes during their search. …”
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Communication-efficient federated learning method via redundant data elimination by Kaiju LI, Qiang XU, Hao WANG

“…To address the influence of limited network bandwidth of edge devices on the communication efficiency of federated learning, and efficiently transmit local model update to complete model aggregation, a communication-efficient federated learning method via redundant data elimination was proposed.The essential reasons for generation of redundant update parameters and according to non-IID properties and model distributed training features of FL were analyzed, a novel sensitivity and loss function tolerance definitions for coreset was given, and a novel federated coreset construction algorithm was proposed.Furthermore, to fit the extracted coreset, a novel distributed adaptive sparse network model evolution mechanism was designed to dynamically adjust the structure and the training model size before each global training iteration, which reduced the number of communication bits between edge devices and the server while also guarantees the training model accuracy.Experimental results show that the proposed method achieves 17% reduction in communication bits transmission while only 0.5% degradation in model accuracy compared with state-of-the-art method.…”
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Gear Tooth Contact Analysis of Cycloidal Pinwheel Transmission Mechanism of RV Reducers by Han Ju, Zhang Weichang

“…The load deformation of the gear teeth with initial clearance is determined, and the model solution is completed using the iterative method. The time-varying force characteristics at the meshing of the gear teeth and the inner and outer rings of the crankshaft bearing roller needles during the transmission process are clarified.…”
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A genetic algorithm based method of optimizing dispersion matrix for RDSM system by Peng ZHANG, Xiaoping JIN, Dongxiao CHEN

“…Rectangular differential spatial modulation (RDSM) is a multi-antenna incoherent modulation technology with high spectral efficiency, low power consumption, and zero-overhead for channel estimation.RDSM is especially suitable for 6G communication systems, such as fast-moving Internet of vehicles, Internet of things, cellular networks, etc.However, the construction of the sparse rectangular unitary space-time dispersion matrix (DM) at transmitter is a problem.The proposed Genetic algorithm (GA) will result in less computational complexity than the currently used random research.The fitness of GA was calculated by the rank and determinant criterion (RDC) method to avoid discussions in differential system.Due to characteristics of constellation symbols of RDSM, the proposed method reduced the computational complexity during each single iteration in GA.The simulation results show that the optimized DMS can significantly improve the bit error rate (BER) performance of the RDSM system.Compared with random search, the low-complexity GA effectively improves the DMS optimization efficiency of RDSM.The computational complexity required for optimizing DMS is about 0.1% of random search optimization method.…”
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LDPC code reconstruction based on algorithm of finding low weight code-words by Pei-dong YU, Hua PENG, Ke-xian GONG, Ze-liang CHEN

“…LDPC code reconstruction without a candidate set is one of the tough problems in channel code reconstruction.First,theoretical analysis was provided for the number of received code-vectors needed for the reconstruction,and a lower bound was derived.Then,according to the lower bound,and based on an algorithm for finding low weight code-words,a new reconstruction method was proposed.It looked for low weight vectors one by one from the dual space of the received code-vector space and used them to reconstruct the sparse parity-check matrices.Number of iterations and the computational complexity of the method were analyzed based on exponential distribution theory.Under noise-free conditions,drawbacks of the existing method,including limited applicable range and large quantity of required data,have been overcame.Under noisy conditions,the proposed method has higher robustness against noise and relatively low complexity,compared to existing methods.For QC-LDPC codes,the reconstruction performance can be further improved using the quasi-cyclic property of their sparse parity-check matrices.…”
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Process Correlation Analysis Model for Process Improvement Identification by Su-jin Choi, Dae-Kyoo Kim, Sooyong Park

“…Process areas and their elements (goals and practices) are often correlated due to the iterative nature of software development process. However, in the current practice, correlations of process elements are often overlooked in the development of an improvement plan, which diminishes the efficiency of the plan. …”
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k-error linear complexity of q-ary sequence of period p² by Chenhuang WU, Chunxiang XU, Xiaoni DU

“…Based on element statistics in a matrix,a new efficient computing method for computing the k-error linear complexity of q-ary sequence of period p<sup>2</sup>was proposed,where p,q were odd primes and q modulo p<sup>2</sup>was primitive.A general result and a concrete proof were showed.To verify the correctness of the result,two kinds of q-ary sequence of period p<sup>2</sup>were illustrated.Because the new method does not need iterative calculation and when it is implemented by program and compared with existing algorithms,the results show that the proposed new algorithm is significantly more efficient in calculating k-error linear complexity of q-ary sequence of period p<sup>2</sup>.…”
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A partial overlapping point cloud registration method based on dynamic feature matching by Hui DU, Changliang ZHENG, Chunyu MIAO, Xiaomeng ZHANG

“…The point cloud registration method can effectively complete the registration of point clouds with different overlap rates and various sizes, and ensure the accuracy of the 3D reconstruction model.To address the above issues, a partial overlapping point cloud registration method based on dynamic feature matching named PPCR was proposed.Firstly, the point cloud was divided into sub-point clouds based on the Euclidean distance segmentation method.Secondly, the features of sub-point clouds were extracted.Since the sizes of different point clouds are varied, the scales of the extracted features are also different.Thus, a dynamic time warping (DTW) algorithm was proposed to map the sub-point clouds.Finally, the registration algorithm was iterated to obtain the translation and rotation matrix between point clouds.This matrix was used to complete the registration and stitching between point clouds.Experimental results show that the proposed method can effectively solve the registration problems of partially overlapping point clouds and point clouds with different scales.…”
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A Stackelberg game based content caching algorithm in energy-harvesting small cell networks by Xueting WANG, Qi ZHU, Han HU

“…The equilibrium solution could be achieved after finite iterations of the two algorithms. The simulation results show that the proposed novel algorithm performs better in user satisfaction and energy-saving comparing with algorithm using principle of proximity.…”
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Hybrid Alternated Inertial Projection and Contraction Algorithm for Solving Bilevel Variational Inequality Problems by Jacob Ashiwere Abuchu, Austine Efut Ofem, Godwin Chidi Ugwunnadi, Ojen Kumar Narain, Azhar Hussain

“…The algorithm which involves alternated inertial uses self-adjustment stepsize condition that depends solely on the information from previous iterative step. The bilevel problem considered in the work consists of upper-level problem with an underlying operator which is pseudomonotone, while the lower problem is associated with strongly monotone mapping and the fixed-point constraint of demimetric mapping. …”
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New Fractional Derivative Expression of the Shifted Third-Kind Chebyshev Polynomials: Application to a Type of Nonlinear Fractional Pantograph Differential Equations by Y. H. Youssri, W. M. Abd-Elhameed, H. M. Ahmed

“…The role of the tau method is to convert the pantograph differential equation with its governing initial/boundary conditions into a nonlinear system of algebraic equations that can be treated with the aid of Newton’s iterative scheme. To test the method’s convergence, certain estimations are included. …”
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Research on constrained policy reinforcement learning based multi-objective optimization of computing power network by Linjiang SHEN, Chang CAO, Chao CUI, Yan ZHANG

“…The computing power network needs to maximize the system performance index on the basis of meeting user business needs, and the existing methods are mainly based on the multi-objective weighting method, which has problems such as difficult to determine hyperparameters and poor cross-scenario applicability.Based on this, based on the analysis of the characteristics of the computing power network target, the user business requirements were taken as the policy constraints, and the performance indicators of the computing power network was taken as the optimization goal based on constrained policy optimization, and the expectation certainty of user business needs and the optimization of system performance through the value-strategy-hyper-parameter multi-level iterative strategy was realized.At the same time, the multi-scale step length (MSL) method for hyper-parameter optimization was studied, which further improved the stability and accuracy of the system.Simulation results show that the proposed method has good convergence and stability under the conditions of single terminal-single edge server, multi-terminal-multi-edge server and system load change.…”
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RESEARCH ON KINEMATIC CALIBRATION METHOD OF THREE DEGREE OF FREEDOM SERIES MANIPULATOR BASED ON BALLBAR by CHE YaXiao, YANG XinGang, GAO Feng, HUANG YuMei, HAN WenTao, GAO Heng

“…After the zero position calibration of the manipulator,measurement data used in calibration process is obtained by one time ballbar installation.An error identification model is built based on the geometric constraints of closed kinematic chain—composed of the manipulator and ballbar as well as the end position error model,then the manipulator geometric parameters errors are calculated using nonlinear least square iterative method. A calibration experiment is completed,and the errors of the manipulator are compensated by integrated error compensation method. …”
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Stability and Bifurcation Analysis of a Delayed Leslie-Gower Predator-Prey System with Nonmonotonic Functional Response by Jiao Jiang, Yongli Song

“…Using the method of upper and lower solutions and monotone iterative scheme, a sufficient condition independent of delay for the global stability of the positive equilibrium is obtained. …”
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