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A New Eighth Order Implicit Block Algorithms for the Direct Solution of Second Order Ordinary Differential Equations
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作者 Ademola M. Badmus 《American Journal of Computational Mathematics》 2014年第4期376-386,共11页
This paper focuses on derivation of a uniform order 8 implicit block method for the direct solution of general second order differential equations through continuous coefficients of Linear Multi-step Method (LMM). The... This paper focuses on derivation of a uniform order 8 implicit block method for the direct solution of general second order differential equations through continuous coefficients of Linear Multi-step Method (LMM). The continuous formulation and its first derivatives were evaluated at some selected grid and off grid points to obtain our proposed method. The superiority of the method over the existing methods is established numerically. 展开更多
关键词 UNIFORM Order Second Order INITIAL Value Problem IMPLICIT block algorithms ZERO Stable
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Some Results for Exact Support Recovery of Block Joint Sparse Matrix via Block Multiple Measurement Vectors Algorithm
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作者 Yingna Pan Pingping Zhang 《Journal of Applied Mathematics and Physics》 2023年第4期1098-1112,共15页
Block multiple measurement vectors (BMMV) is a reconstruction algorithm that can be used to recover the support of block K-joint sparse matrix X from Y = ΨX + V. In this paper, we propose a sufficient condition for a... Block multiple measurement vectors (BMMV) is a reconstruction algorithm that can be used to recover the support of block K-joint sparse matrix X from Y = ΨX + V. In this paper, we propose a sufficient condition for accurate support recovery of the block K-joint sparse matrix via the BMMV algorithm in the noisy case. Furthermore, we show the optimality of the condition we proposed in the absence of noise when the problem reduces to single measurement vector case. 展开更多
关键词 Support Recovery Compressed Sensing block Multiple Measurement Vectors algorithm block Restricted Isometry Property
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A hybrid genetic-simulated annealing algorithm for optimization of hydraulic manifold blocks 被引量:7
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作者 刘万辉 田树军 +1 位作者 贾春强 曹宇宁 《Journal of Shanghai University(English Edition)》 CAS 2008年第3期261-267,共7页
This paper establishes a mathematical model of multi-objective optimization with behavior constraints in solid space based on the problem of optimal design of hydraulic manifold blocks (HMB). Due to the limitation o... This paper establishes a mathematical model of multi-objective optimization with behavior constraints in solid space based on the problem of optimal design of hydraulic manifold blocks (HMB). Due to the limitation of its local search ability of genetic algorithm (GA) in solving a massive combinatorial optimization problem, simulated annealing (SA) is combined, the multi-parameter concatenated coding is adopted, and the memory function is added. Thus a hybrid genetic-simulated annealing with memory function is formed. Examples show that the modified algorithm can improve the local search ability in the solution space, and the solution quality. 展开更多
关键词 hydraulic manifold blocks (HMB) genetic algorithm (GA) simulated annealing (SA) optimal design
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Optimal design of hydraulic manifold blocks based on niching genetic simulated annealing algorithm 被引量:1
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作者 贾春强 Yu Ling +1 位作者 Tian Shujun Gao Yanming 《High Technology Letters》 EI CAS 2007年第4期363-368,共6页
关键词 水力学 遗传 退火算法 生态位
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BLOCK ADAPTIVE RECURSIVE ALGORITHM FOR VIDEO CONFERENCE CODING
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作者 Tu Guofang(Graduate School, University of Science and Technology of China, Beijing 100039)Zhang Can(704 Institute, Company of Aero-Space Industry, Beijing 100076) 《Journal of Electronics(China)》 1996年第2期140-146,共7页
This paper presents a new motion estimation algorithm for video conference signal coding. This type of algorithm is called block adaptive recursive algorithm (BARA). Simulation results show that this new algorithm has... This paper presents a new motion estimation algorithm for video conference signal coding. This type of algorithm is called block adaptive recursive algorithm (BARA). Simulation results show that this new algorithm has better performance than conventional ones. 展开更多
关键词 MOTION estimation block ADAPTIVE RECURSIVE algorithm MOTION compensated IMAGE CODING
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AN IMPROVED FAST BLIND DECONVOLUTION ALGORITHM BASED ON DECORRELATION AND BLOCK MATRIX
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作者 Yang Jun'an He Xuefan 《Journal of Electronics(China)》 2008年第5期577-582,共6页
In order to alleviate the shortcomings of most blind deconvolution algorithms,this paper proposes an improved fast algorithm for blind deconvolution based on decorrelation technique and broadband block matrix.Althougt... In order to alleviate the shortcomings of most blind deconvolution algorithms,this paper proposes an improved fast algorithm for blind deconvolution based on decorrelation technique and broadband block matrix.Althougth the original algorithm can overcome the shortcomings of current blind deconvolution algorithms,it has a constraint that the number of the source signals must be less than that of the channels.The improved algorithm deletes this constraint by using decorrelation technique.Besides,the improved algorithm raises the separation speed in terms of improving the computing methods of the output signal matrix.Simulation results demonstrate the validation and fast separation of the improved algorithm. 展开更多
关键词 通信技术 盲去卷积 快速算法 解相关
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Adaptive block greedy algorithms for receiving multi-narrowband signal in compressive sensing radar reconnaissance receiver
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作者 ZHANG Chaozhu XU Hongyi JIANG Haiqing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第6期1158-1169,共12页
This paper extends the application of compressive sensing(CS) to the radar reconnaissance receiver for receiving the multi-narrowband signal. By combining the concept of the block sparsity, the self-adaption methods, ... This paper extends the application of compressive sensing(CS) to the radar reconnaissance receiver for receiving the multi-narrowband signal. By combining the concept of the block sparsity, the self-adaption methods, the binary tree search,and the residual monitoring mechanism, two adaptive block greedy algorithms are proposed to achieve a high probability adaptive reconstruction. The use of the block sparsity can greatly improve the efficiency of the support selection and reduce the lower boundary of the sub-sampling rate. Furthermore, the addition of binary tree search and monitoring mechanism with two different supports self-adaption methods overcome the instability caused by the fixed block length while optimizing the recovery of the unknown signal.The simulations and analysis of the adaptive reconstruction ability and theoretical computational complexity are given. Also, we verify the feasibility and effectiveness of the two algorithms by the experiments of receiving multi-narrowband signals on an analogto-information converter(AIC). Finally, an optimum reconstruction characteristic of two algorithms is found to facilitate efficient reception in practical applications. 展开更多
关键词 compressive sensing(CS) adaptive greedy algorithm block sparsity analog-to-information convertor(AIC) multinarrowband signal
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Adaptive Decoding Algorithm Based on Multiplicity of Candidate Sequences for Block Turbo Codes
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作者 DANG Xiaoyu TAN Min YU Xiangbin 《China Communications》 SCIE CSCD 2014年第A01期9-15,共7页
关键词 分组TURBO码 测试序列 解码算法 自适应技术 多重 自适应算法 迭代译码算法 信号噪声比
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Analysis and Design for Unsymmetrical Block Encryption Algorithm
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作者 王以刚 孔令飞 《Journal of China Textile University(English Edition)》 EI CAS 1999年第2期50-52,共3页
This article explains the imbalance in DES and introduces the operators in IDEA. At last it puts forward a Unsym-metrical Block Encryption Algorithm which is achieved by adding some operators to DES.
关键词 BLACK CIPHER CIPHER algorithm DES IDEA UNSYMMETRICAL block ENCRYPTION
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An Electronic Image Stabilization Algorithm Based on Efficient Block Matching on the Bitplane
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作者 Luo Fang Qin Xiaozhen 《Open Journal of Applied Sciences》 2013年第1期1-5,共5页
This paper proposes an electronic image stabilization algorithm based on efficient block matching on the plane. This algorithm uses a hexagonal search algorithm, and uses the bit-planes to estimate and compensate for ... This paper proposes an electronic image stabilization algorithm based on efficient block matching on the plane. This algorithm uses a hexagonal search algorithm, and uses the bit-planes to estimate and compensate for the translational motion between video sequences at the same time;As for the rotary motion vector generated in the video sequences, in order to highlight the intensity change of the image sequence, the algorithm firstly conducts Laplace transform for the reference frame, then select a number of characteristics at the image edge to make block matching with the current frame, calculate and compensate for the rotational movement that may exist finally. Through theoretical analysis and simula-tion, we prove that, as for a mixed translational and rotational motion video sequences, the proposed algorithm can reduce required time for block matching computation ,while improving the accuracy of the electronic image stabilization. 展开更多
关键词 Electronic Image STABILIZATION algorithm BIT PLANE block MATCHING HEXAGON Motion Estimation
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基于FPGA的TANGRAM分组密码算法实现
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作者 王建新 许弘可 +3 位作者 郑玉崝 肖超恩 张磊 洪睿鹏 《计算机应用研究》 CSCD 北大核心 2024年第1期260-265,共6页
TANGRAM系列分组密码算法是一种采用比特切片方法,适合多种软硬件平台的系列分组密码算法。针对TANGRAM-128/128算法,使用Verilog HDL对该算法进行FPGA实现并提出设计方案。首先,介绍了TANGRAM密码算法的特点和流程,提出了针对TANGRAM... TANGRAM系列分组密码算法是一种采用比特切片方法,适合多种软硬件平台的系列分组密码算法。针对TANGRAM-128/128算法,使用Verilog HDL对该算法进行FPGA实现并提出设计方案。首先,介绍了TANGRAM密码算法的特点和流程,提出了针对TANGRAM密码算法进行44轮加/解密迭代计算的方案,该方案采取有限状态机的方法有效降低了资源消耗;其次,基于国产高云云源平台,完成了基于高云FPGA的算法工程实现,以及功能仿真和数据的正确性验证,同时在QuartusⅡ13.1.0平台上也进行了相关测试,用以比较。测试结果表明,TANGRAM系列分组密码算法基于Altera公司的CycloneⅣE系列EP4CE40F29C6芯片进行工程实现,最大时钟频率为138.64 MHz,加/解密速率为403.30 Mbps;基于高云半导体GW2A-55系列芯片的最大时钟频率为96.537 MHz,加/解密速率为280.80 Mbps。 展开更多
关键词 TANGRAM 分组密码算法 Verilog HDL 有限状态机
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质量体积双约束下车辆装载与配送路径联合优化研究
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作者 任宗伟 钱志军 +3 位作者 郑玮 蒲炜 张宁 祁彬彬 《包装工程》 CAS 北大核心 2024年第9期232-242,共11页
目的针对质量与体积共同限制的配送路径问题,综合考虑订单不可拆分、货物的体积等约束,构建包含路径最短和装载率最高双目标的车辆装载与配送路径联合优化模型。方法在车辆路径优化模型的求解方面,首先利用聚类算法对配送区域进行划分,... 目的针对质量与体积共同限制的配送路径问题,综合考虑订单不可拆分、货物的体积等约束,构建包含路径最短和装载率最高双目标的车辆装载与配送路径联合优化模型。方法在车辆路径优化模型的求解方面,首先利用聚类算法对配送区域进行划分,然后通过车辆的载质量判断是否能进行站点货物的配送,最后利用遗传算法求得最优路径。在三维装载模型的求解上使用贪心算法和基于块的启发式算法,解决了货物的装箱问题。结果基于某公司具体实例对模型与算法的可行性进行了验证,优化后配送的车辆减少了1辆,配送距离减少了154.247 km,平均装载率达到了93.89%,节省了企业的配送成本。结论所构建的模型以及求解的算法可以提高装载率和配送效率,为解决车辆装载与配送路径联合优化问题提供理论依据。 展开更多
关键词 路径优化 遗传算法 三维装载 基于块的启发式算法
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积分故障分析下的Midori128密码算法安全性评估
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作者 魏悦川 贺水喻 +1 位作者 潘峰 王湘儒 《国防科技大学学报》 EI CAS CSCD 北大核心 2024年第4期229-238,共10页
为了研究Midori128密码算法针对积分故障攻击的安全性,建立积分区分器平衡位置、故障密文与轮密钥的关系,通过密钥搜索,可以恢复出算法的最后一轮密钥,进而利用密钥扩展算法恢复出主密钥。理论分析表明,利用3轮和4轮积分区分器进行积分... 为了研究Midori128密码算法针对积分故障攻击的安全性,建立积分区分器平衡位置、故障密文与轮密钥的关系,通过密钥搜索,可以恢复出算法的最后一轮密钥,进而利用密钥扩展算法恢复出主密钥。理论分析表明,利用3轮和4轮积分区分器进行积分故障攻击时,恢复出正确密钥的时间复杂度分别为2^(21)和2^(24)。采用准确性、成功率和耗费时间对倒数第4轮注入故障的攻击过程进行仿真,成功恢复出该算法的主密钥,并且针对不同明文分组和密钥进行对比实验。通过两组故障安全性分析方案可知,Midori128算法的轮函数易受到积分故障攻击,在算法运行时至少需要对倒数6轮进行故障检测等额外防护。 展开更多
关键词 轻量级分组密码 Midori128算法 积分区分器 积分故障分析
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Solving Job-Shop Scheduling Problems by Genetic Algorithms Based on Building Block Hypothesis
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作者 CHENG Rong CHEN You-ping LI Zhi-gang 《International Journal of Plant Engineering and Management》 2006年第2期119-123,共5页
In this paper, we propose a new genetic algorithm for job-shop scheduling problems (JSP). The proposed method uses the operation-based representation, based on schema theorem and building block hypothesis, a new cro... In this paper, we propose a new genetic algorithm for job-shop scheduling problems (JSP). The proposed method uses the operation-based representation, based on schema theorem and building block hypothesis, a new crossover is proposed : By selecting short, low order highly fit schemas to genetic operator, the crossover can exchange meaningful ordering information of parents effectively and can search the global optimization. Simulation results on MT benchmark problem coded by C + + show that our genetic operators are very powerful and suitable to job-shop scheduling problems and our method outperforms the previous GA-based approaches. 展开更多
关键词 job-shop scheduling genetic algorithm schema theorem building block hypothesis
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面向准时化生产的船体分段排产分析
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作者 王冲 彭江 《船舶工程》 CSCD 北大核心 2024年第3期117-123,共7页
针对国内某典型船厂存在的智能化程度低、作业方案可控性差和库存成本高等问题,以减少船体分段的库存时间、满足分段的开工时间限制和保证胎位负荷均衡为目标建立数学模型,并引入遗传算法解决此类NP-Hard问题。在算法运行过程中采用混... 针对国内某典型船厂存在的智能化程度低、作业方案可控性差和库存成本高等问题,以减少船体分段的库存时间、满足分段的开工时间限制和保证胎位负荷均衡为目标建立数学模型,并引入遗传算法解决此类NP-Hard问题。在算法运行过程中采用混沌映射、精英保留策略和自适应交叉变异算子增强算法的全局寻优性和收敛性。对某船厂的实际生产数据进行计算和对比分析,结果表明,采用改进算法所得结果比船厂排产计划库存时间更少,资源利用率更高,该算法有效。 展开更多
关键词 分段排产 遗传算法 精益造船 准时化 混沌搜索
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Single bitmap block truncation coding of color images using hill climbing algorithm
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作者 张力戈 Qin Xiaolin +2 位作者 Li Qing Peng Haoyue Hou Yu 《High Technology Letters》 EI CAS 2019年第4期355-363,共9页
In order to generate an efficient common bitmap in single bitmap block truncation coding(SBBTC)of color images,an improved SBBTC scheme based on weighted plane(W-plane)method and hill climbing algorithm is proposed.Fi... In order to generate an efficient common bitmap in single bitmap block truncation coding(SBBTC)of color images,an improved SBBTC scheme based on weighted plane(W-plane)method and hill climbing algorithm is proposed.Firstly,the incoming color image is partitioned into non-overlapping blocks and each block is encoded using the W-plane method to get an initial common bitmap and quantization values.Then,the hill climbing algorithm is applied to optimize an initial common bitmap and generate a near-optimized common bitmap.Finally,the quantization values are recalculated by the near-optimized common bitmap and the considered color image is reconstructed block by block through the common bitmap and the new quantization values.Since the processing of each image block in SBBTC is independent and identical,parallel computing is applied to reduce the time consumption of this scheme.The simulation results show that the proposed scheme has better visual quality and time consumption than those of the reference SBBTC schemes. 展开更多
关键词 block TRUNCATION coding(BTC) common BITMAP parallel computing HILL CLIMBING algorithm
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A Novel Decoder Based on Parallel Genetic Algorithms for Linear Block Codes
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作者 Abdeslam Ahmadi Faissal El Bouanani +1 位作者 Hussain Ben-Azza Youssef Benghabrit 《International Journal of Communications, Network and System Sciences》 2013年第1期66-76,共11页
Genetic algorithms offer very good performances for solving large optimization problems, especially in the domain of error-correcting codes. However, they have a major drawback related to the time complexity and memor... Genetic algorithms offer very good performances for solving large optimization problems, especially in the domain of error-correcting codes. However, they have a major drawback related to the time complexity and memory occupation when running on a uniprocessor computer. This paper proposes a parallel decoder for linear block codes, using parallel genetic algorithms (PGA). The good performance and time complexity are confirmed by theoretical study and by simulations on BCH(63,30,14) codes over both AWGN and flat Rayleigh fading channels. The simulation results show that the coding gain between parallel and single genetic algorithm is about 0.7 dB at BER = 10﹣5 with only 4 processors. 展开更多
关键词 CHANNEL Coding Linear block Codes META-HEURISTICS PARALLEL Genetic algorithmS PARALLEL Decoding algorithmS Time Complexity Flat FADING CHANNEL AWGN
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Research on variable block size motion estimation algorithm for airborne image
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作者 王科 Huang Dongshan +1 位作者 Ma Li Zhang Yudong 《High Technology Letters》 EI CAS 2014年第3期321-327,共7页
A fast motion estimation algorithm for variable block-size using the "line scan and block merge procedure" is proposed for airborne image compression modules.Full hardware implementation via FPGA is discusse... A fast motion estimation algorithm for variable block-size using the "line scan and block merge procedure" is proposed for airborne image compression modules.Full hardware implementation via FPGA is discussed in detail.The proposed pipelined architecture based on the line scan algorithm is capable of calculating the required 41 motion vectors of various size blocks supported by H.264 within a 16 X 16 block in parallel.An adaptive rate distortion cost function is used for various size block decision.The motion vectors of adjacent small blocks are merged to predict the motion vectors of larger blocks for reducing computation.Experimental results show that our proposed method has lower computational complexity than full search algorithm with slight quality decrease and little bit rate increase.Due to the high real-time processing speed it can be easily realized in hardware. 展开更多
关键词 快速运动估计算法 图像压缩 机载 可变 运动矢量 流水线结构 计算复杂度 全搜索算法
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25轮T-TWINE-128的中间相遇攻击
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作者 刘亚 刘采玥 +1 位作者 颜勇 曲博 《小型微型计算机系统》 CSCD 北大核心 2024年第5期1228-1234,共7页
T-TWINE-128是基于广义Feistel结构的轻量级可调分组密码,密钥长度为128比特,加密的数据块大小为64比特.由于轻量级分组密码在设计时为了追求更高的软硬件实现效率,往往会牺牲部分安全性,因此必须评估其安全强度.本文通过计算机编程得到... T-TWINE-128是基于广义Feistel结构的轻量级可调分组密码,密钥长度为128比特,加密的数据块大小为64比特.由于轻量级分组密码在设计时为了追求更高的软硬件实现效率,往往会牺牲部分安全性,因此必须评估其安全强度.本文通过计算机编程得到了T-TWINE-128的轮密钥的一些线性关系,再结合调柄值生成算法的特性,利用区分器自动搜索算法,搜索出11轮T-TWINE-128的中间相遇攻击区分器,在此区分器前面接5轮,后面接9轮,形成25轮T-TWINE-128的中间相遇攻击路径,整个攻击过程共耗时652.39ms,攻击需要数据、时间和存储复杂度分别为256个选择明文、2126.41次加密、265个64比特块;最后搜索密钥编排算法的冗余性发现T-TWINE-128很难进行更高轮中间相遇攻击. 展开更多
关键词 T-TWINE 中间相遇攻击 轻量可调分组密码 自动搜索算法
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基于IB-SURF算法的无人机图像拼接技术研究 被引量:2
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作者 江智 江德港 +2 位作者 黄子杰 郭彩玲 李柏林 《计算机工程与应用》 CSCD 北大核心 2024年第3期263-269,共7页
针对传统SURF算法(speeded up robust features)在拼接高分辨率无人机航拍图像时运行速度慢、特征匹配率低的特点,提出了一种基于IB-SURF(image block-SURF)技术的无人机图像拼接算法。结合无人机定位定姿系统(position and orientation... 针对传统SURF算法(speeded up robust features)在拼接高分辨率无人机航拍图像时运行速度慢、特征匹配率低的特点,提出了一种基于IB-SURF(image block-SURF)技术的无人机图像拼接算法。结合无人机定位定姿系统(position and orientation system,POS)求取图像重叠区域;构造掩模在无人机图像重叠区域检测特征点,减少特征提取时间;借助图像分块(image block,IB)的思想对图像划分网格,精简筛选特征点;引入Neighborhood-KNN(neighborhood-K nearest neighbors)进行特征点匹配,提高图像匹配效率。实验结果表明,IB-SURF算法有较快的运行速度和较高的特征匹配率,平均特征匹配率达到84.3%,特征匹配正确率超过95.1%,为图像高质量拼接提供了技术基础。 展开更多
关键词 无人机图像 IB-SURF算法 特征点提取 图像分块
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