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A Review of Image Steganography Based on Multiple Hashing Algorithm
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作者 Abdullah Alenizi Mohammad Sajid Mohammadi +1 位作者 Ahmad A.Al-Hajji Arshiya Sajid Ansari 《Computers, Materials & Continua》 SCIE EI 2024年第8期2463-2494,共32页
Steganography is a technique for hiding secret messages while sending and receiving communications through a cover item.From ancient times to the present,the security of secret or vital information has always been a s... Steganography is a technique for hiding secret messages while sending and receiving communications through a cover item.From ancient times to the present,the security of secret or vital information has always been a significant problem.The development of secure communication methods that keep recipient-only data transmissions secret has always been an area of interest.Therefore,several approaches,including steganography,have been developed by researchers over time to enable safe data transit.In this review,we have discussed image steganography based on Discrete Cosine Transform(DCT)algorithm,etc.We have also discussed image steganography based on multiple hashing algorithms like the Rivest–Shamir–Adleman(RSA)method,the Blowfish technique,and the hash-least significant bit(LSB)approach.In this review,a novel method of hiding information in images has been developed with minimal variance in image bits,making our method secure and effective.A cryptography mechanism was also used in this strategy.Before encoding the data and embedding it into a carry image,this review verifies that it has been encrypted.Usually,embedded text in photos conveys crucial signals about the content.This review employs hash table encryption on the message before hiding it within the picture to provide a more secure method of data transport.If the message is ever intercepted by a third party,there are several ways to stop this operation.A second level of security process implementation involves encrypting and decrypting steganography images using different hashing algorithms. 展开更多
关键词 Image steganography multiple hashing algorithms hash-LSB approach RSA algorithm discrete cosine transform(DCT)algorithm blowfish algorithm
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基于Vision Transformer Hashing的民族布艺图案哈希检索算法研究 被引量:1
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作者 韩雨萌 宁涛 +1 位作者 段晓东 高原 《大连民族大学学报》 CAS 2023年第3期250-254,共5页
针对民族布艺图案复杂多样、语义提取、图像识别与检索困难等问题,以蜡染图案和织锦图案为例,提出一种图像检索算法,以提高匹配和检索民族布艺图案的准确度。结合民族布艺图案领域知识将民族布艺图案图像进行预处理,使用VIT为主干网络... 针对民族布艺图案复杂多样、语义提取、图像识别与检索困难等问题,以蜡染图案和织锦图案为例,提出一种图像检索算法,以提高匹配和检索民族布艺图案的准确度。结合民族布艺图案领域知识将民族布艺图案图像进行预处理,使用VIT为主干网络在哈希检索算法框架下进行图像检索。该方法优化了深度哈希检索算法,通过自身的自注意力机制提升了提取图案深层语义特征的能力,提高了深度哈希算法检索民族布艺图案的速度和精度。实验结果表明:提出的方法最佳检索精度可以达到95.32%。 展开更多
关键词 图像检索 深度哈希检索 VIT 民族布艺图案检索
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An Efficient Encrypted Speech Retrieval Based on Unsupervised Hashing and B+ Tree Dynamic Index
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作者 Qiu-yu Zhang Yu-gui Jia +1 位作者 Fang-Peng Li Le-Tian Fan 《Computers, Materials & Continua》 SCIE EI 2023年第7期107-128,共22页
Existing speech retrieval systems are frequently confronted with expanding volumes of speech data.The dynamic updating strategy applied to construct the index can timely process to add or remove unnecessary speech dat... Existing speech retrieval systems are frequently confronted with expanding volumes of speech data.The dynamic updating strategy applied to construct the index can timely process to add or remove unnecessary speech data to meet users’real-time retrieval requirements.This study proposes an efficient method for retrieving encryption speech,using unsupervised deep hashing and B+ tree dynamic index,which avoid privacy leak-age of speech data and enhance the accuracy and efficiency of retrieval.The cloud’s encryption speech library is constructed by using the multi-threaded Dijk-Gentry-Halevi-Vaikuntanathan(DGHV)Fully Homomorphic Encryption(FHE)technique,which encrypts the original speech.In addition,this research employs Residual Neural Network18-Gated Recurrent Unit(ResNet18-GRU),which is used to learn the compact binary hash codes,store binary hash codes in the designed B+tree index table,and create a mapping relation of one to one between the binary hash codes and the corresponding encrypted speech.External B+tree index technology is applied to achieve dynamic index updating of the B+tree index table,thereby satisfying users’needs for real-time retrieval.The experimental results on THCHS-30 and TIMIT showed that the retrieval accuracy of the proposed method is more than 95.84%compared to the existing unsupervised hashing methods.The retrieval efficiency is greatly improved.Compared to the method of using hash index tables,and the speech data’s security is effectively guaranteed. 展开更多
关键词 Encrypted speech retrieval unsupervised deep hashing learning to hash B+tree dynamic index DGHV fully homomorphic encryption
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TECMH:Transformer-Based Cross-Modal Hashing For Fine-Grained Image-Text Retrieval
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作者 Qiqi Li Longfei Ma +2 位作者 Zheng Jiang Mingyong Li Bo Jin 《Computers, Materials & Continua》 SCIE EI 2023年第5期3713-3728,共16页
In recent years,cross-modal hash retrieval has become a popular research field because of its advantages of high efficiency and low storage.Cross-modal retrieval technology can be applied to search engines,crossmodalm... In recent years,cross-modal hash retrieval has become a popular research field because of its advantages of high efficiency and low storage.Cross-modal retrieval technology can be applied to search engines,crossmodalmedical processing,etc.The existing main method is to use amulti-label matching paradigm to finish the retrieval tasks.However,such methods do not use fine-grained information in the multi-modal data,which may lead to suboptimal results.To avoid cross-modal matching turning into label matching,this paper proposes an end-to-end fine-grained cross-modal hash retrieval method,which can focus more on the fine-grained semantic information of multi-modal data.First,the method refines the image features and no longer uses multiple labels to represent text features but uses BERT for processing.Second,this method uses the inference capabilities of the transformer encoder to generate global fine-grained features.Finally,in order to better judge the effect of the fine-grained model,this paper uses the datasets in the image text matching field instead of the traditional label-matching datasets.This article experiment on Microsoft COCO(MS-COCO)and Flickr30K datasets and compare it with the previous classicalmethods.The experimental results show that this method can obtain more advanced results in the cross-modal hash retrieval field. 展开更多
关键词 Deep learning cross-modal retrieval hash learning TRANSFORMER
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ViT2CMH:Vision Transformer Cross-Modal Hashing for Fine-Grained Vision-Text Retrieval
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作者 Mingyong Li Qiqi Li +1 位作者 Zheng Jiang Yan Ma 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期1401-1414,共14页
In recent years,the development of deep learning has further improved hash retrieval technology.Most of the existing hashing methods currently use Convolutional Neural Networks(CNNs)and Recurrent Neural Networks(RNNs)... In recent years,the development of deep learning has further improved hash retrieval technology.Most of the existing hashing methods currently use Convolutional Neural Networks(CNNs)and Recurrent Neural Networks(RNNs)to process image and text information,respectively.This makes images or texts subject to local constraints,and inherent label matching cannot capture finegrained information,often leading to suboptimal results.Driven by the development of the transformer model,we propose a framework called ViT2CMH mainly based on the Vision Transformer to handle deep Cross-modal Hashing tasks rather than CNNs or RNNs.Specifically,we use a BERT network to extract text features and use the vision transformer as the image network of the model.Finally,the features are transformed into hash codes for efficient and fast retrieval.We conduct extensive experiments on Microsoft COCO(MS-COCO)and Flickr30K,comparing with baselines of some hashing methods and image-text matching methods,showing that our method has better performance. 展开更多
关键词 hash learning cross-modal retrieval fine-grained matching TRANSFORMER
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Secure Content Based Image Retrieval Scheme Based on Deep Hashing and Searchable Encryption
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作者 Zhen Wang Qiu-yu Zhang +1 位作者 Ling-tao Meng Yi-lin Liu 《Computers, Materials & Continua》 SCIE EI 2023年第6期6161-6184,共24页
To solve the problem that the existing ciphertext domain image retrieval system is challenging to balance security,retrieval efficiency,and retrieval accuracy.This research suggests a searchable encryption and deep ha... To solve the problem that the existing ciphertext domain image retrieval system is challenging to balance security,retrieval efficiency,and retrieval accuracy.This research suggests a searchable encryption and deep hashing-based secure image retrieval technique that extracts more expressive image features and constructs a secure,searchable encryption scheme.First,a deep learning framework based on residual network and transfer learn-ing model is designed to extract more representative image deep features.Secondly,the central similarity is used to quantify and construct the deep hash sequence of features.The Paillier homomorphic encryption encrypts the deep hash sequence to build a high-security and low-complexity searchable index.Finally,according to the additive homomorphic property of Paillier homomorphic encryption,a similarity measurement method suitable for com-puting in the retrieval system’s security is ensured by the encrypted domain.The experimental results,which were obtained on Web Image Database from the National University of Singapore(NUS-WIDE),Microsoft Common Objects in Context(MS COCO),and ImageNet data sets,demonstrate the system’s robust security and precise retrieval,the proposed scheme can achieve efficient image retrieval without revealing user privacy.The retrieval accuracy is improved by at least 37%compared to traditional hashing schemes.At the same time,the retrieval time is saved by at least 9.7%compared to the latest deep hashing schemes. 展开更多
关键词 Content-based image retrieval deep supervised hashing central similarity quantification searchable encryption Paillier homomorphic encryption
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Analysis of pseudo-random number generators in QMC-SSE method
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作者 刘东旭 徐维 张学锋 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期75-79,共5页
In the quantum Monte Carlo(QMC)method,the pseudo-random number generator(PRNG)plays a crucial role in determining the computation time.However,the hidden structure of the PRNG may lead to serious issues such as the br... In the quantum Monte Carlo(QMC)method,the pseudo-random number generator(PRNG)plays a crucial role in determining the computation time.However,the hidden structure of the PRNG may lead to serious issues such as the breakdown of the Markov process.Here,we systematically analyze the performance of different PRNGs on the widely used QMC method known as the stochastic series expansion(SSE)algorithm.To quantitatively compare them,we introduce a quantity called QMC efficiency that can effectively reflect the efficiency of the algorithms.After testing several representative observables of the Heisenberg model in one and two dimensions,we recommend the linear congruential generator as the best choice of PRNG.Our work not only helps improve the performance of the SSE method but also sheds light on the other Markov-chain-based numerical algorithms. 展开更多
关键词 stochastic series expansion quantum Monte Carlo pseudo-random number generator
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Underwater Pulse Waveform Recognition Based on Hash Aggregate Discriminant Network
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作者 WANG Fangchen ZHONG Guoqiang WANG Liang 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期654-660,共7页
Underwater pulse waveform recognition is an important method for underwater object detection.Most existing works focus on the application of traditional pattern recognition methods,which ignore the time-and space-vary... Underwater pulse waveform recognition is an important method for underwater object detection.Most existing works focus on the application of traditional pattern recognition methods,which ignore the time-and space-varying characteristics in sound propagation channels and cannot easily extract valuable waveform features.Sound propagation channels in seawater are time-and space-varying convolutional channels.In the extraction of the waveform features of underwater acoustic signals,the effect of high-accuracy underwater acoustic signal recognition is identified by eliminating the influence of time-and space-varying convolutional channels to the greatest extent possible.We propose a hash aggregate discriminative network(HADN),which combines hash learning and deep learning to minimize the time-and space-varying effects on convolutional channels and adaptively learns effective underwater waveform features to achieve high-accuracy underwater pulse waveform recognition.In the extraction of the hash features of acoustic signals,a discrete constraint between clusters within a hash feature class is introduced.This constraint can ensure that the influence of convolutional channels on hash features is minimized.In addition,we design a new loss function called aggregate discriminative loss(AD-loss).The use of AD-loss and softmax-loss can increase the discriminativeness of the learned hash features.Experimental results show that on pool and ocean datasets,which were collected in pools and oceans,respectively,by using acoustic collectors,the proposed HADN performs better than other comparative models in terms of accuracy and mAP. 展开更多
关键词 convolutional channel hash aggregate discriminative network aggregate discriminant loss waveform recognition
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基于多重熵Hash及Box-Cox蓄电池续航时长分析与仿真
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作者 邓翠艳 齐小刚 +1 位作者 姚旭清 李青云 《通信与信息技术》 2024年第4期18-22,共5页
现代工业生产中,蓄电池是市电停电后通信网络业务能够持续运行的重要保障,是化解网络风险发生的重要一环。针对目前通信行业蓄电池智能化管理水平不高,尤其对于蓄电池的剩余寿命及续航时长无法测算,导致通信机房停电后无法准确预估蓄电... 现代工业生产中,蓄电池是市电停电后通信网络业务能够持续运行的重要保障,是化解网络风险发生的重要一环。针对目前通信行业蓄电池智能化管理水平不高,尤其对于蓄电池的剩余寿命及续航时长无法测算,导致通信机房停电后无法准确预估蓄电池的续航时长。针对该问题,首先设计了一种基于信息熵的多重哈希(Hash)查询方法,然后提出了一种基于对数似然函数优化方法的Box-Cox算法,实现蓄电池时序运维数据续航时长的平稳化处理。实验结果表明对于大量的通信机房运维数据,通过基于熵的多重哈希(Hash)方法进行数据查询结构设计并使用最优化参数的Box-Cox算法可以有效计算得到蓄电池的续航时长。该方法能够将蓄电池机房运维数据转化为蓄电池续航时长生产知识数据,实现通信机房蓄电池能耗的有效管理运营,实际生产实践也证明了该方法的可行性。 展开更多
关键词 多重hash Box-Cox 对数似然函数 蓄电池 续航时长 剩余寿命
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基于Simhash算法的题库查重系统的设计与实现
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作者 熊良钰 邓伦丹 《科学技术创新》 2024年第9期91-94,共4页
Simhash算法是一种基于局部敏感哈希(LSH)的技术,以其快速的计算速度和高度的查重准确性而知名。该算法通过将文本特征转换为二进制码,进而通过计算这些二进制码之间的汉明距离来评估文本的相似度。在文本去重和重复文档检测等多个领域,... Simhash算法是一种基于局部敏感哈希(LSH)的技术,以其快速的计算速度和高度的查重准确性而知名。该算法通过将文本特征转换为二进制码,进而通过计算这些二进制码之间的汉明距离来评估文本的相似度。在文本去重和重复文档检测等多个领域,Simhash算法已经展现出了显著的效果。鉴于此,将Simhash算法应用于题库查重具有很高的可行性和实际应用价值。 展开更多
关键词 Simhash算法 汉明距离 题库查重系统 文本相似度计算 哈希函数
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基于word-hashing的DGA僵尸网络深度检测模型 被引量:8
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作者 赵科军 葛连升 +1 位作者 秦丰林 洪晓光 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2017年第A01期30-33,共4页
针对使用域名生成算法(DGA)僵尸网络隐蔽性强,传统检测算法特征提取复杂的问题,提出一种无需提取具体特征的深度学习模型DGA域名检测方法.首先基于word-hashing将所有域名转用二元语法字符串表示,利用词袋模型把域名映射到高维向量空间... 针对使用域名生成算法(DGA)僵尸网络隐蔽性强,传统检测算法特征提取复杂的问题,提出一种无需提取具体特征的深度学习模型DGA域名检测方法.首先基于word-hashing将所有域名转用二元语法字符串表示,利用词袋模型把域名映射到高维向量空间.然后利用5层深度神经网络对转换为高维向量的域名进行训练分类检测.通过深度模型,能够从训练数据中发现不同层次抽象的隐藏模式和特征,而这些模式和特征使用传统的统计方法大多是无法发现的.实验中使用了10万条DGA域名和10万条合法域名作为样本,与基于自然语言特征分类算法进行对比实验.实验结果表明该深度模型对DGA域名检测准确率达到97.23%,比基于自然语言特征分类算法得到的检测准确率高3.7%. 展开更多
关键词 DGA 僵尸网络 wordhashing 深度学习
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基于直方图量化和混沌系统的感知图像Hashing算法 被引量:1
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作者 邓绍江 王方晓 +1 位作者 张岱固 王瑜 《计算机应用》 CSCD 北大核心 2008年第11期2804-2807,共4页
研究了基于图像灰度级压缩的直方图差值量化(DQH)技术,并结合混沌系统,提出了一种新的感知图像Hash ing算法。算法首先利用混沌系统把压缩后的图像中各个灰度级的出现概率调制成一个固定长度的中间Hash序列;然后将中间Hash序列经过差值... 研究了基于图像灰度级压缩的直方图差值量化(DQH)技术,并结合混沌系统,提出了一种新的感知图像Hash ing算法。算法首先利用混沌系统把压缩后的图像中各个灰度级的出现概率调制成一个固定长度的中间Hash序列;然后将中间Hash序列经过差值量化和二值量化得到最终的图像Hash序列。仿真结果表明,该算法对JPEG压缩、低通滤波、图像缩放和旋转等操作有良好的鲁棒性,而且混沌系统的引入使算法具有较强的安全性。 展开更多
关键词 图像hash 差值量化 混沌系统 直方图
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Trie Hashing结构平均路径长度分析
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作者 王宏 熊西文 朱振文 《大连理工大学学报》 EI CAS CSCD 北大核心 1991年第5期507-514,共8页
针对 W.Litwin提出的 Trie Hashing结构的路径长度分析问题,研究并揭示 了该结构所具有的某些新的性质;建立了必要的分析前提.从而给出了 Trie Hashing 结构平均路径长度的分析方法。所得估计式仅与... 针对 W.Litwin提出的 Trie Hashing结构的路径长度分析问题,研究并揭示 了该结构所具有的某些新的性质;建立了必要的分析前提.从而给出了 Trie Hashing 结构平均路径长度的分析方法。所得估计式仅与外部结点数目有关,理论分析与模拟 实验的结果表明,对于 Trie Hashing 结构,文中的分析方法明显优于 Klein 和 wood的类似结果。 展开更多
关键词 T-H结构 算法分析
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动态HASHING算法及其改进
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作者 王艳军 安小宇 《光盘技术》 2009年第6期51-,53,共2页
对两种动态散列算法可扩展散列和线形散列进行了研究,提出了改进的动态散列算法。改进算法避免了不必要的溢出桶,散列桶的数量线性增长,避免了因查找键分布异常而出现频繁的桶分裂及桶地址表更新的现象。
关键词 动态散列 可扩展散列 线性散列
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基于变色龙hash的区块链可扩展存储方案 被引量:3
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作者 胡宁玉 郝耀军 +1 位作者 常建龙 冯丽萍 《计算机应用研究》 CSCD 北大核心 2023年第12期3539-3544,3550,共7页
区块链中的节点以副本形式保存数据,随着时间的推移,区块链中的区块数不断增加,导致节点承受的存储压力随之增大,存储压力成为区块链应用落地的瓶颈之一。为了解决区块链中存储压力问题,提出了基于变色龙hash的区块链可扩展存储方案,该... 区块链中的节点以副本形式保存数据,随着时间的推移,区块链中的区块数不断增加,导致节点承受的存储压力随之增大,存储压力成为区块链应用落地的瓶颈之一。为了解决区块链中存储压力问题,提出了基于变色龙hash的区块链可扩展存储方案,该方案利用节点被攻击成功的概率和改进的温度模型,将区块分为高低安全性的冷热区块;基于变色龙hash算法和改进的Merkle tree,对高安全性的冷区块进行部分节点存储。在存储过程中,除高安全性冷区块的区块体信息被重构外,其余数据保持不变。仿真实验表明,在不改变区块链结构和安全性能的情况下,所提出的方案可减少区块链中数据的存储总量,减少存储节点的存储压力;且区块数量越多,其优势越明显。 展开更多
关键词 区块链 变色龙hash 存储扩展性
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Recent development of perceptual image hashing 被引量:7
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作者 王朔中 张新鹏 《Journal of Shanghai University(English Edition)》 CAS 2007年第4期323-331,共9页
The easy generation, storage, transmission and reproduction of digital images have caused serious abuse and security problems. Assurance of the rightful ownership, integrity, and authenticity is a major concern to the... The easy generation, storage, transmission and reproduction of digital images have caused serious abuse and security problems. Assurance of the rightful ownership, integrity, and authenticity is a major concern to the academia as well as the industry. On the other hand, efficient search of the huge amount of images has become a great challenge. Image hashing is a technique suitable for use in image authentication and content based image retrieval (CBIR). In this article, we review some representative image hashing techniques proposed in the recent years, with emphases on how to meet the conflicting requirements of perceptual robustness and security. Following a brief introduction to some earlier methods, we focus on a typical two-stage structure and some geometric-distortion resilient techniques. We then introduce two image hashing approaches developed in our own research, and reveal security problems in some existing methods due to the absence of secret keys in certain stage of the image feature extraction, or availability of a large quantity of images, keys, or the hash function to the adversary. More research efforts are needed in developing truly robust and secure image hashing techniques. 展开更多
关键词 image hashing perceptual robustness SECURITY image authentication.
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基于RS_Hash频繁项集的卫星载荷关联规则算法
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作者 贾澎涛 温滋 《国外电子测量技术》 北大核心 2023年第2期9-15,共7页
遥测数据是反映卫星健康状态的重要依据,对遥测载荷数据进行关联性分析,在一定程度上能反映出卫星的整体运行情况的好坏。针对传统关联规则算法存在效率低下、占用内存过多的问题,提出一种基于RS_Hash频繁项集的卫星载荷关联规则算法。... 遥测数据是反映卫星健康状态的重要依据,对遥测载荷数据进行关联性分析,在一定程度上能反映出卫星的整体运行情况的好坏。针对传统关联规则算法存在效率低下、占用内存过多的问题,提出一种基于RS_Hash频繁项集的卫星载荷关联规则算法。首先对事务数据库使用动态随机抽样的方法获取样本数据,设计抽样误差和抽样停止规则来确定最优的样本容量;其次将抽取出的样本使用哈希桶来存储频繁项集,进而减少占用的内存,提高算法的运行效率;最后使用3个与载荷数据相似的公开数据集和卫星载荷数据集进行实验,结果表明,在公共数据集上取得了良好的效果,尤其是在具有大数据量级的卫星载荷数据集上效果明显,在不同事务长度和支持度的情况下,相较于Apriori、PCY、SON、FP-Growth、RCM_Apriori和Hash_Cumulate算法,RS_Hash算法在平均时间效率上分别提高了75.81%、49.10%、59.38%、50.22%、40.16%和39.22%。 展开更多
关键词 卫星载荷分析 关联规则 频繁项集 动态随机抽样算法 哈希桶
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机群系统上基于Hashing的多目标串匹配并行算法
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作者 范曾 钟诚 +1 位作者 莫倩芸 刘萍 《微电子学与计算机》 CSCD 北大核心 2007年第9期165-168,共4页
基于孙子定理构造均匀的Hash函数并继承Karp-Rabin模式匹配思想,利用"筛选"方法,给出一种机群系统上的多目标串匹配并行算法。通过预处理将字符串映射成惟一的一对整数值,采用比较一对整数值来取代逐个字符比较字符串的方法... 基于孙子定理构造均匀的Hash函数并继承Karp-Rabin模式匹配思想,利用"筛选"方法,给出一种机群系统上的多目标串匹配并行算法。通过预处理将字符串映射成惟一的一对整数值,采用比较一对整数值来取代逐个字符比较字符串的方法使得匹配过程快速且比较结果是确定的;"筛选"节省了比较时间。算法分析和实验结果表明该并行算法简明、高效和可扩展。 展开更多
关键词 多目标串匹配:词典匹配:并行算法:hashing:机群系统
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Fast Near-duplicate Image Detection in Riemannian Space by A Novel Hashing Scheme 被引量:2
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作者 Ligang Zheng Chao Song 《Computers, Materials & Continua》 SCIE EI 2018年第9期529-539,共11页
There is a steep increase in data encoded as symmetric positive definite(SPD)matrix in the past decade.The set of SPD matrices forms a Riemannian manifold that constitutes a half convex cone in the vector space of mat... There is a steep increase in data encoded as symmetric positive definite(SPD)matrix in the past decade.The set of SPD matrices forms a Riemannian manifold that constitutes a half convex cone in the vector space of matrices,which we sometimes call SPD manifold.One of the fundamental problems in the application of SPD manifold is to find the nearest neighbor of a queried SPD matrix.Hashing is a popular method that can be used for the nearest neighbor search.However,hashing cannot be directly applied to SPD manifold due to its non-Euclidean intrinsic geometry.Inspired by the idea of kernel trick,a new hashing scheme for SPD manifold by random projection and quantization in expanded data space is proposed in this paper.Experimental results in large scale nearduplicate image detection show the effectiveness and efficiency of the proposed method. 展开更多
关键词 RIEMANNIAN MANIFOLD CONGRUENT transformation hashing KERNEL TRICK
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Robust Image Hashing via Random Gabor Filtering and DWT 被引量:4
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作者 Zhenjun Tang Man Ling +4 位作者 Heng Yao Zhenxing Qian Xianquan Zhang Jilian Zhang Shijie Xu 《Computers, Materials & Continua》 SCIE EI 2018年第5期331-344,共14页
Image hashing is a useful multimedia technology for many applications,such as image authentication,image retrieval,image copy detection and image forensics.In this paper,we propose a robust image hashing based on rand... Image hashing is a useful multimedia technology for many applications,such as image authentication,image retrieval,image copy detection and image forensics.In this paper,we propose a robust image hashing based on random Gabor filtering and discrete wavelet transform(DWT).Specifically,robust and secure image features are first extracted from the normalized image by Gabor filtering and a chaotic map called Skew tent map,and then are compressed via a single-level 2-D DWT.Image hash is finally obtained by concatenating DWT coefficients in the LL sub-band.Many experiments with open image datasets are carried out and the results illustrate that our hashing is robust,discriminative and secure.Receiver operating characteristic(ROC)curve comparisons show that our hashing is better than some popular image hashing algorithms in classification performance between robustness and discrimination. 展开更多
关键词 Image hashing Gabor filtering chaotic map skew tent map discrete wavelet transform.
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