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The continuous wavelet projections algorithm: A practical spectral-feature-mining approach for crop detection 被引量:4
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作者 Xiaohu Zhao Jingcheng Zhang +3 位作者 Ruiliang Pu Zaifa Shu Weizhong He Kaihua Wu 《The Crop Journal》 SCIE CSCD 2022年第5期1264-1273,共10页
Spectroscopy can be used for detecting crop characteristics. A goal of crop spectrum analysis is to extract effective features from spectral data for establishing a detection model. An ideal spectral feature set shoul... Spectroscopy can be used for detecting crop characteristics. A goal of crop spectrum analysis is to extract effective features from spectral data for establishing a detection model. An ideal spectral feature set should have high sensitivity to target parameters but low information redundancy among features.However, feature-selection methods that satisfy both requirements are lacking. To address this issue,in this study, a novel method, the continuous wavelet projections algorithm(CWPA), was developed,which has advantages of both continuous wavelet analysis(CWA) and the successive projections algorithm(SPA) for generating optimal spectral feature set for crop detection. Three datasets collected for crop stress detection and retrieval of biochemical properties were used to validate the CWPA under both classification and regression scenarios. The CWPA generated a feature set with fewer features yet achieving accuracy comparable to or even higher than those of CWA and SPA. With only two to three features identified by CWPA, an overall accuracy of 98% in classifying tea plant stresses was achieved, and high coefficients of determination were obtained in retrieving corn leaf chlorophyll content(R^(2)= 0.8521)and equivalent water thickness(R^(2)= 0.9508). The mechanism of the CWPA ensures that the novel algorithm discovers the most sensitive features while retaining complementarity among features. Its ability to reduce the data dimension suggests its potential for crop monitoring and phenotyping with hyperspectral data. 展开更多
关键词 HYPERSPECTRAL Crop parameters Crop phenotyping Continuous wavelet analysis Successive projections algorithm
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Approximate subgradient projection algorithm for convex feasibility problem 被引量:1
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作者 Li Li Yan Gao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第3期527-530,共4页
An ε-subgradient projection algorithm for solving a convex feasibility problem is presented.Based on the iterative projection methods and the notion of ε-subgradient,a series of special projection hyperplanes is est... An ε-subgradient projection algorithm for solving a convex feasibility problem is presented.Based on the iterative projection methods and the notion of ε-subgradient,a series of special projection hyperplanes is established.Moreover,compared with the existing projection hyperplanes methods with subgradient,the proposed hyperplanes are interactive with ε,and their ranges are more larger.The convergence of the proposed algorithm is given under some mild conditions,and the validity of the algorithm is proved by the numerical test. 展开更多
关键词 ε-subgradient projection algorithm convex feasibility problem.
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Distributed projection subgradient algorithm for two-network zero-sum game with random sleep scheme 被引量:1
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作者 Hongyun Xiong Jiangxiong Han +1 位作者 Xiaohong Nian Shiling Li 《Control Theory and Technology》 EI CSCD 2021年第3期405-417,共13页
In this paper,a zero-sum game Nash equilibrium computation problem with a common constraint set is investigated under two time-varying multi-agent subnetworks,where the two subnetworks have opposite payoff function.A ... In this paper,a zero-sum game Nash equilibrium computation problem with a common constraint set is investigated under two time-varying multi-agent subnetworks,where the two subnetworks have opposite payoff function.A novel distributed projection subgradient algorithm with random sleep scheme is developed to reduce the calculation amount of agents in the process of computing Nash equilibrium.In our algorithm,each agent is determined by an independent identically distributed Bernoulli decision to compute the subgradient and perform the projection operation or to keep the previous consensus estimate,it effectively reduces the amount of computation and calculation time.Moreover,the traditional assumption of stepsize adopted in the existing methods is removed,and the stepsizes in our algorithm are randomized diminishing.Besides,we prove that all agents converge to Nash equilibrium with probability 1 by our algorithm.Finally,a simulation example verifies the validity of our algorithm. 展开更多
关键词 Zero-sum game Nash equilibrium Time-varying multi-agent network projection subgradient algorithm Random sleep scheme
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A PROJECTION-TYPE ALGORITHM FOR SOLVING GENERALIZED MIXED VARIATIONAL INEQUALITIES 被引量:2
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作者 涂凯 夏福全 《Acta Mathematica Scientia》 SCIE CSCD 2016年第6期1619-1630,共12页
We propose a projection-type algorithm for generalized mixed variational in- equality problem in Euclidean space Rn. We establish the convergence theorem for the pro- posed algorithm, provided the multi-valued mapping... We propose a projection-type algorithm for generalized mixed variational in- equality problem in Euclidean space Rn. We establish the convergence theorem for the pro- posed algorithm, provided the multi-valued mapping is continuous and f-pseudomonotone with nonempty compact convex values on dom(f), where f : Rn --RU{+∞} is a proper func- tion. The algorithm presented in this paper generalize and improve some known algorithms in literatures. Preliminary computational experience is also reported. 展开更多
关键词 projection-type algorithm generalized mixed variational inequality f-pseudo-monotone mapping
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Improved differential evolution algorithm for resource-constrained project scheduling problem 被引量:4
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作者 Lianghong Wu Yaonan Wang Shaowu Zhou 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第5期798-805,共8页
An improved differential evolution(IDE)algorithm that adopts a novel mutation strategy to speed up the convergence rate is introduced to solve the resource-constrained project scheduling problem(RCPSP)with the obj... An improved differential evolution(IDE)algorithm that adopts a novel mutation strategy to speed up the convergence rate is introduced to solve the resource-constrained project scheduling problem(RCPSP)with the objective of minimizing project duration Activities priorities for scheduling are represented by individual vectors and a senal scheme is utilized to transform the individual-represented priorities to a feasible schedule according to the precedence and resource constraints so as to be evaluated.To investigate the performance of the IDE-based approach for the RCPSP,it is compared against the meta-heuristic methods of hybrid genetic algorithm(HGA),particle swarm optimization(PSO) and several well selected heuristics.The results show that the proposed scheduling method is better than general heuristic rules and is able to obtain the same optimal result as the HGA and PSO approaches but more efficient than the two algorithms. 展开更多
关键词 differential evolution algorithm project soheduling resource constraint priority-based scheduling.
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Low side lobe pattern synthesis using projection method with genetic algorithm for truncated cone conformal phased arrays 被引量:9
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作者 Guoqi Zeng Siyin Li +1 位作者 Yan Zhang Shanwei L 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第4期554-559,共6页
A hybrid method for synthesizing antenna's three dimensional (3D) pattern is proposed to obtain the low sidelobe feature of truncated cone conformal phased arrays. In this method, the elements of truncated cone con... A hybrid method for synthesizing antenna's three dimensional (3D) pattern is proposed to obtain the low sidelobe feature of truncated cone conformal phased arrays. In this method, the elements of truncated cone conformal phased arrays are projected to the tangent plane in one generatrix of the truncated cone. Then two dimensional (2D) Chebyshev amplitude distribution optimization is respectively used in two mutual vertical directions of the tangent plane. According to the location of the elements, the excitation current amplitude distribution of each element on the conformal structure is derived reversely, then the excitation current amplitude is further optimized by using the genetic algorithm (GA). A truncated cone problem with 8x8 elements on it, and a 3D pattern desired side lobe level (SLL) up to 35 dB, is studied. By using the hybrid method, the optimal goal is accomplished with acceptable CPU time, which indicates that this hybrid method for the low sidelobe synthesis is feasible. 展开更多
关键词 conformal phased array low side lobe pattern synthe-sis projection method genetic algorithm optimization.
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Research and Implementation for License Plate Recognition Based on Improved Projection Algorithm 被引量:1
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作者 LI Xiu-juan Yimamu' aishan.Abudoulikemu 《Computer Aided Drafting,Design and Manufacturing》 2013年第2期53-56,75,共5页
This paper analyzes and dissertates the discrete wavelet transform and improved projection algorithm in four kernel stages (image preprocessing, license plate localization, character segmentation, license plate recog... This paper analyzes and dissertates the discrete wavelet transform and improved projection algorithm in four kernel stages (image preprocessing, license plate localization, character segmentation, license plate recognition, i.e.) of license plate recognition system in detail. At last, it gives some conclusions and suggestions on future research. 展开更多
关键词 license plate recognition wavelet transform improved projection algorithm
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An algorithm for computed tomography image reconstruction from limited-view projections 被引量:5
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作者 王林元 李磊 +3 位作者 闫镔 江成顺 王浩宇 包尚联 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期642-647,共6页
With the development of the compressive sensing theory, the image reconstruction from the projections viewed in limited angles is one of the hot problems in the research of computed tomography technology. This paper d... With the development of the compressive sensing theory, the image reconstruction from the projections viewed in limited angles is one of the hot problems in the research of computed tomography technology. This paper develops an iterative algorithm for image reconstruction, which can fit the most cases. This method gives an image reconstruction flow with the difference image vector, which is based on the concept that the difference image vector between the reconstructed and the reference image is sparse enough. Then the l1-norm minimization method is used to reconstruct the difference vector to recover the image for flat subjects in limited angles. The algorithm has been tested with a thin planar phantom and a real object in limited-view projection data. Moreover, all the studies showed the satisfactory results in accuracy at a rather high reconstruction speed. 展开更多
关键词 limited-view problem computed tomography image reconstruction algorithms reconstruction-reference difference algorithm adaptive steepest descent-projection onto convex sets algorithm
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Hybrid alternate projection algorithm and its application for practical conformal array pattern synthesis
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作者 Fei Zhao Shunlian Chai +2 位作者 Huiying Qi Ke Xiao Junjie Mao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第5期625-632,共8页
Based on the fabricated 12-element cavity-backed microstrip sector cylinder array,a novel hybrid alternate projection algorithm(HAPA),which combines analytical method with numerical techniques effectively,is propose... Based on the fabricated 12-element cavity-backed microstrip sector cylinder array,a novel hybrid alternate projection algorithm(HAPA),which combines analytical method with numerical techniques effectively,is proposed for synthesizing the pattern of practical conformal array.The algorithm applies the variable direction aperture projection method with mutual coupling correction techniques to provide the good initial excitations of elements to the enhanced alternate projection algorithm(EAPA).In order to do further optimization,which improves the convergent speed of the algorithm significantly.Finally,the HAPA has been applied to the fabricated sector cylinder array with mutual coupling considered.The results of synthesized patterns,such as low sidelobe with null points formed pattern,beam scanning with low sidelobe pattern and the shaped beam pattern are presented.It demonstrates the validity of HAPA in practical conformal array synthesis. 展开更多
关键词 conformal array alternate projection algorithm aperture projection method pattern synthesis mutual coupling
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New hybrid inertial CQ projection algorithms with line-search process for the split feasibility problem
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作者 DANG Ya-zheng WANG Long YANG Yao-heng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第1期144-158,共15页
In this paper, we propose two hybrid inertial CQ projection algorithms with linesearch process for the split feasibility problem. Based on the hybrid CQ projection algorithm, we firstly add the inertial term into the ... In this paper, we propose two hybrid inertial CQ projection algorithms with linesearch process for the split feasibility problem. Based on the hybrid CQ projection algorithm, we firstly add the inertial term into the iteration to accelerate the convergence of the algorithm, and adopt flexible rules for selecting the stepsize and the shrinking projection region, which makes an optimal stepsize available at each iteration. The shrinking projection region is the intersection of three sets, which are the set C and two hyperplanes. Furthermore, we modify the Armijo-type line-search step in the presented algorithm to get a new algorithm.The algorithms are shown to be convergent under certain mild assumptions. Besides, numerical examples are given to show that the proposed algorithms have better performance than the general CQ algorithm. 展开更多
关键词 split feasible problem INERTIAL Armijo-type line-search technique projection algorithm CONVERGENCE
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Fast Affine Projection Algorithm for Adaptive Noise Canceling and Its Application on the Fetal Electrocardiogram Extraction 被引量:1
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作者 宫延伟 吉小军 +1 位作者 黄峰一 阮晓虹 《Journal of Shanghai Jiaotong university(Science)》 EI 2009年第6期690-694,共5页
Aimed at the problem of adaptive noise canceling(ANC),three implementary algorithms which are least mean square(LMS) algorithm,recursive least square(RLS) algorithm and fast affine projection(FAP) algorithm,have been ... Aimed at the problem of adaptive noise canceling(ANC),three implementary algorithms which are least mean square(LMS) algorithm,recursive least square(RLS) algorithm and fast affine projection(FAP) algorithm,have been researched.The simulations were made for the performance of these algorithms.The extraction of fetal electrocardiogram(FECG) is applied to compare the application effect of the above algorithms.The proposed FAP algorithm has obvious advantages in computational complexity,convergence speed and steadystate error. 展开更多
关键词 adaptive noise canceling (ANC) least mean square (LMS) algorithm recursive least square (RLS) algorithm fast affine projection (FAP) algorithm fetal electrocardiogram (FECG)
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Fuzzy Flexible Resource Constrained Project Scheduling Based on Genetic Algorithm 被引量:1
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作者 查鸿 张连营 《Transactions of Tianjin University》 EI CAS 2014年第6期469-474,共6页
Both fuzzy temporal constraint and flexible resource constraint are considered in project scheduling. In order to obtain an optimal schedule, we propose a genetic algorithm integrated with concepts on fuzzy set theory... Both fuzzy temporal constraint and flexible resource constraint are considered in project scheduling. In order to obtain an optimal schedule, we propose a genetic algorithm integrated with concepts on fuzzy set theory as well as specialized coding and decoding mechanism. An example demonstrates that the proposed approach can assist the project managers to obtain the optimal schedule effectively and make the correct decision on skill training before a project begins. 展开更多
关键词 project SCHEDULING FUZZINESS FLEXIBILITY GENETIC algorithm TRAINING
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BEAM BROADENING SYNTHESIS FOR SAR ANTENNA ARRAY BASED ON PROJECTION MATRIX ALGORITHM
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作者 Jiao Junjun Sun Huifeng 《Journal of Electronics(China)》 2014年第5期433-440,共8页
A new beam broadening synthesis technique for Synthetic Aperture Radar(SAR) antenna array, namely Projection Matrix Algorithm(PMA) is presented. The theory of PMA is introduced firstly, and then the iterative renewed ... A new beam broadening synthesis technique for Synthetic Aperture Radar(SAR) antenna array, namely Projection Matrix Algorithm(PMA) is presented. The theory of PMA is introduced firstly, and then the iterative renewed manner is improved to resolve the unbalance problem under amplitude and phase control. In order to validate the algorithm correct and effective, an actual engineering application example is investigated. The beam synthesis results of 1.0~4.5 times broadening under the phase only control and the amplitude and phase control using improved PMA are given. The results show that the beam directivity, the beam broadening, and the side-lobe level requirements were met. It is demonstrated that the improved PMA was effective and feasible for SAR application. 展开更多
关键词 Synthetic Aperture Radar(SAR) antenna array Beam broadening synthesis projection Matrix algorithm(PMA) Phase only control Amplitude and phase control
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Hybrid algorithm for project scheduling with capacity constraint 被引量:1
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作者 Cheng Xu Wu Cheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第5期1041-1046,共6页
Motivated by the projects constrained by space capacity and resource transporting time, a project scheduling probIem with capacity constraint was modeled. A hybrid algorithm is proposed, which uses the ideas of bi-lev... Motivated by the projects constrained by space capacity and resource transporting time, a project scheduling probIem with capacity constraint was modeled. A hybrid algorithm is proposed, which uses the ideas of bi-level scheduling and project decomposition technology, and the genetic algorithm and tabu search is combined. Topological reordering technology is used to improve the efficiency of evaluation. Simulation results show the proposed algorithm can obtain satisfied scheduling results in acceptable time. 展开更多
关键词 project scheduling capacity constraint heuristic algorithm bi-level scheduling.
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An Evolutionary Algorithm with Multi-Local Search for the Resource-Constrained Project Scheduling Problem
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作者 Zhi-Jie Chen Chiuh-Cheng Chyu 《Intelligent Information Management》 2010年第3期220-226,共7页
This paper introduces a hybrid evolutionary algorithm for the resource-constrained project scheduling problem (RCPSP). Given an RCPSP instance, the algorithm identifies the problem structure and selects a suitable dec... This paper introduces a hybrid evolutionary algorithm for the resource-constrained project scheduling problem (RCPSP). Given an RCPSP instance, the algorithm identifies the problem structure and selects a suitable decoding scheme. Then a multi-pass biased sampling method followed up by a multi-local search is used to generate a diverse and good quality initial population. The population then evolves through modified order-based recombination and mutation operators to perform exploration for promising solutions within the entire region. Mutation is performed only if the current population has converged or the produced offspring by recombination operator is too similar to one of his parents. Finally the algorithm performs an intensified local search on the best solution found in the evolutionary stage. Computational experiments using standard instances indicate that the proposed algorithm works well in both computational time and solution quality. 展开更多
关键词 RESOURCE-CONSTRAINED project SCHEDULING EVOLUTIONARY algorithmS Local SEARCH HYBRIDIZATION
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智能网联环境下混合交通均衡分配:模型与算法 被引量:1
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作者 王建 刘哲宁 王炜 《中国公路学报》 北大核心 2025年第5期198-208,共11页
随着智能网联车技术的发展和市场渗透率不断提升,未来将呈现人驾车与智能网联车混行的交通流环境。由于人驾车与智能网联车在驾驶特性及路径选择行为上存在巨大差异,交通运行特征与网络流量将发生深刻变化,如何准确预测混合交通网络均... 随着智能网联车技术的发展和市场渗透率不断提升,未来将呈现人驾车与智能网联车混行的交通流环境。由于人驾车与智能网联车在驾驶特性及路径选择行为上存在巨大差异,交通运行特征与网络流量将发生深刻变化,如何准确预测混合交通网络均衡流是开展智能网联交通规划和管理的基础和前提。以构建智能网联混合交通均衡模型和快速求解算法为研究目标,首先分析混合流交通运行特征,以及智能网联车队列驾驶和聚合程度对路段通行能力与阻抗的影响,建立混合交通阻抗分析模型;随后,根据各类车辆路径选择行为特征,基于变分不等式构建logit型随机用户均衡与用户均衡混合分配模型;最后,针对传统混合均衡分配问题求解精度不高、收敛速度慢的情况,提出一种改进型梯度投影算法,通过耦合模型二阶导数信息,有效提高收敛速度和求解精度、降低计算时间。在Sioux-Falls与宁波市路网的实际应用表明:相比于传统的路径流量交换算法,提出的改进型梯度投影法能够提升一个数量级的精度;相比于已有的路径流量交换算法,上述2个路网同精度求解时间分别缩短91.1%和92.4%。 展开更多
关键词 交通工程 交通均衡分配 梯度投影算法 混合流交通 智能网联交通 交通阻抗
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Memetic algorithm for multi-mode resource-constrained project scheduling problems 被引量:1
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作者 Shixin Liu Di Chen Yifan Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第4期609-617,共9页
A memetic algorithm (MA) for a multi-mode resourceconstrained project scheduling problem (MRCPSP) is proposed. We use a new fitness function and two very effective local search procedures in the proposed MA. The f... A memetic algorithm (MA) for a multi-mode resourceconstrained project scheduling problem (MRCPSP) is proposed. We use a new fitness function and two very effective local search procedures in the proposed MA. The fitness function makes use of a mechanism called "strategic oscillation" to make the search process have a higher probability to visit solutions around a "feasible boundary". One of the local search procedures aims at improving the lower bound of project makespan to be less than a known upper bound, and another aims at improving a solution of an MRCPSP instance accepting infeasible solutions based on the new fitness function in the search process. A detailed computational experiment is set up using instances from the problem instance library PSPLIB. Computational results show that the proposed MA is very competitive with the state-of-the-art algorithms. The MA obtains improved solutions for one instance of set J30. 展开更多
关键词 project scheduling RESOURCE-CONSTRAINED multi-mode memetic algorithm (MA) local search procedure.
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A Dynamic Programming Algorithm on Project- Gang Investment Decision Making
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作者 Xu Xu-song Wu Jian-mou 《Wuhan University Journal of Natural Sciences》 CAS 2002年第4期403-407,共5页
The investment decision making of Project Gang, the projects that are associated with one another on economy and technique, is studied. In order to find out the best Scheme that can make the maximum profit, a dynami... The investment decision making of Project Gang, the projects that are associated with one another on economy and technique, is studied. In order to find out the best Scheme that can make the maximum profit, a dynamic programming algorithm on the investment decision making of Project Gang is brought forward, and this algorithm can find out the best Scheme of distributing the m resources to the n Items in the time of O(m 2 n). 展开更多
关键词 project-Gang investment decision making dynamic programming algorithm
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基于误差自适应仿射投影算法的水声自干扰抑制方法
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作者 陈聪 胡科学 +3 位作者 史文涛 金勇 魏倩 肖启阳 《电信科学》 北大核心 2025年第10期44-57,共14页
在带内全双工(in-band full-duplex,IBFD)水声通信系统的自干扰(self-interference,SI)抑制中,水下计算资源受限使得传统稀疏信道估计算法难以应对时变、多径、噪声密集的信道特性,无法兼顾收敛速度与估计精度。为此,提出基于误差自适... 在带内全双工(in-band full-duplex,IBFD)水声通信系统的自干扰(self-interference,SI)抑制中,水下计算资源受限使得传统稀疏信道估计算法难以应对时变、多径、噪声密集的信道特性,无法兼顾收敛速度与估计精度。为此,提出基于误差自适应补偿收缩仿射投影算法(error-adaptive compensated shrinkage af‐fine projection algorithm,EA-CS-APA)的水声SI抑制方法。该方法通过引入基于误差能量的选择更新机制抑制无效参数扰动,并构建误差与步长的非线性映射实现自适应步长调整,有效平衡收敛速度与稳态精度。实验结果表明,与补偿收缩仿射投影算法(compensated shrinkage affine projection algorithm,CS-APA)相比,所提方法在归一化均方差、SI抑制性能和计算效率方面分别提升约20%、10%和40%,在复杂时变多径环境下表现出更鲁棒的性能优势,为计算资源受限的水下通信设备提供了有效的SI抑制解决方案。 展开更多
关键词 水声通信 自干扰抑制 仿射投影算法 自适应滤波 稀疏信道估计
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结构洞理论视角下的复杂工程支配网络综合项目排序方法 被引量:3
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作者 张可 刘思敏 +1 位作者 张政 马敏 《系统管理学报》 北大核心 2025年第2期389-399,共11页
复杂工程包含的项目众多,对项目的重要性进行综合排序,是工程实际决策亟须解决的问题。然而,现有方法忽略了项目之间的联系且分析视角单一,导致排序结果区分度不高。为此,基于复杂工程支配网络,提出结构洞理论视角下的综合项目排序方法... 复杂工程包含的项目众多,对项目的重要性进行综合排序,是工程实际决策亟须解决的问题。然而,现有方法忽略了项目之间的联系且分析视角单一,导致排序结果区分度不高。为此,基于复杂工程支配网络,提出结构洞理论视角下的综合项目排序方法。首先,引入结构洞理论,构建项目影响广泛性的度量模型。其次,利用k-shell算法对项目中心度进行重要性评价及层级划分,构建项目的全局重要度评价模型。在此基础上,融合结构洞理论与k-shell算法,提出项目重要性综合排序方法。最后,将该方法应用于算例网络和实际工程,并与其他方法进行了对比分析。结果显示,提出的项目排序方法具有更高的区分度,能够适应项目评价的多维度要求,为复杂工程的决策提供了参考。 展开更多
关键词 工程支配网络 结构洞理论 k-shell算法 项目排序
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