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Highly reliable and efficient encoding systems for hexadecimal polypeptide-based data storage 被引量:2
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作者 Yubin Ren Yi Zhang +7 位作者 Yawei Liu Qinglin Wu Hong-Gang Hu Jingjing Li Chunhai Fan Dong Chen Kai Liu Hongjie Zhang 《Fundamental Research》 CAS CSCD 2023年第2期298-304,共7页
Polypeptides consisting of amino acid(AA)sequences are suitable for high-density information storage.However,the lack of suitable encoding systems,which accommodate the characteristics of polypeptide synthesis,storage... Polypeptides consisting of amino acid(AA)sequences are suitable for high-density information storage.However,the lack of suitable encoding systems,which accommodate the characteristics of polypeptide synthesis,storage and sequencing,impedes the application of polypeptides for large-scale digital data storage.To address this,two reliable and highly efficient encoding systems,i.e.RaptorQ-Arithmetic-Base64-Shuffle-RS(RABSR)and RaptorQArithmetic-Huffman-Rotary-Shuffle-RS(RAHRSR)systems,are developed for polypeptide data storage.The two encoding systems realized the advantages of compressing data,correcting errors of AA chain loss,correcting errors within AA chains,eliminating homopolymers,and pseudo-randomized encrypting.The coding efficiency without arithmetic compression and error correction of audios,pictures and texts by the RABSR system was 3.20,3.12 and 3.53 Bits/AA,respectively.While that using the RAHRSR system reached 4.89,4.80 and 6.84 Bits/AA,respectively.When implemented with redundancy for error correction and arithmetic compression to reduce redundancy,the coding efficiency of audios,pictures and texts by the RABSR system was 4.43,4.36 and 5.22 Bits/AA,respectively.This efficiency further increased to 7.24,7.11 and 9.82 Bits/AA by the RAHRSR system,respectively.Therefore,the developed hexadecimal polypeptide-based systems may provide a new scenario for highly reliable and highly efficient data storage. 展开更多
关键词 Biomaterial POLYPEPTIDE Data storage HEXADECIMAL encoding system
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Variational data encoding and correlations in quantum-enhanced machine learning
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作者 Ming-Hao Wang Hua L¨u 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期298-306,共9页
Leveraging the extraordinary phenomena of quantum superposition and quantum correlation,quantum computing offers unprecedented potential for addressing challenges beyond the reach of classical computers.This paper tac... Leveraging the extraordinary phenomena of quantum superposition and quantum correlation,quantum computing offers unprecedented potential for addressing challenges beyond the reach of classical computers.This paper tackles two pivotal challenges in the realm of quantum computing:firstly,the development of an effective encoding protocol for translating classical data into quantum states,a critical step for any quantum computation.Different encoding strategies can significantly influence quantum computer performance.Secondly,we address the need to counteract the inevitable noise that can hinder quantum acceleration.Our primary contribution is the introduction of a novel variational data encoding method,grounded in quantum regression algorithm models.By adapting the learning concept from machine learning,we render data encoding a learnable process.This allowed us to study the role of quantum correlation in data encoding.Through numerical simulations of various regression tasks,we demonstrate the efficacy of our variational data encoding,particularly post-learning from instructional data.Moreover,we delve into the role of quantum correlation in enhancing task performance,especially in noisy environments.Our findings underscore the critical role of quantum correlation in not only bolstering performance but also in mitigating noise interference,thus advancing the frontier of quantum computing. 展开更多
关键词 QUANTUM MACHINE learning VARIATIONAL data encoding QUANTUM correlation
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A novel encoding mechanism for particle physics
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作者 Zhi‑Guang Tan Sheng‑Jie Wang +2 位作者 You‑Neng Guo Hua Zheng Aldo Bonasera 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第8期153-166,共14页
This study proposes a novel particle encoding mechanism that seamlessly incorporates the quantum properties of particles,with a specific emphasis on constituent quarks.The primary objective of this mechanism is to fac... This study proposes a novel particle encoding mechanism that seamlessly incorporates the quantum properties of particles,with a specific emphasis on constituent quarks.The primary objective of this mechanism is to facilitate the digital registration and identification of a wide range of particle information.Its design ensures easy integration with different event generators and digital simulations commonly used in high-energy experiments.Moreover,this innovative framework can be easily expanded to encode complex multi-quark states comprising up to nine valence quarks and accommodating an angular momentum of up to 99/2.This versatility and scalability make it a valuable tool. 展开更多
关键词 Multi-quark state encoding mechanism Constituent quark Particle physics
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A Two-Layer Encoding Learning Swarm Optimizer Based on Frequent Itemsets for Sparse Large-Scale Multi-Objective Optimization
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作者 Sheng Qi Rui Wang +3 位作者 Tao Zhang Xu Yang Ruiqing Sun Ling Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1342-1357,共16页
Traditional large-scale multi-objective optimization algorithms(LSMOEAs)encounter difficulties when dealing with sparse large-scale multi-objective optimization problems(SLM-OPs)where most decision variables are zero.... Traditional large-scale multi-objective optimization algorithms(LSMOEAs)encounter difficulties when dealing with sparse large-scale multi-objective optimization problems(SLM-OPs)where most decision variables are zero.As a result,many algorithms use a two-layer encoding approach to optimize binary variable Mask and real variable Dec separately.Nevertheless,existing optimizers often focus on locating non-zero variable posi-tions to optimize the binary variables Mask.However,approxi-mating the sparse distribution of real Pareto optimal solutions does not necessarily mean that the objective function is optimized.In data mining,it is common to mine frequent itemsets appear-ing together in a dataset to reveal the correlation between data.Inspired by this,we propose a novel two-layer encoding learning swarm optimizer based on frequent itemsets(TELSO)to address these SLMOPs.TELSO mined the frequent terms of multiple particles with better target values to find mask combinations that can obtain better objective values for fast convergence.Experi-mental results on five real-world problems and eight benchmark sets demonstrate that TELSO outperforms existing state-of-the-art sparse large-scale multi-objective evolutionary algorithms(SLMOEAs)in terms of performance and convergence speed. 展开更多
关键词 Evolutionary algorithms learning swarm optimiza-tion sparse large-scale optimization sparse large-scale multi-objec-tive problems two-layer encoding.
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A highly reliable encoding and decoding communication framework based on semantic information
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作者 Yichi Zhang Haitao Zhao +4 位作者 Kuo Cao Li Zhou Zhe Wang Yueling Liu Jibo Wei 《Digital Communications and Networks》 SCIE CSCD 2024年第3期509-518,共10页
Increasing research has focused on semantic communication,the goal of which is to convey accurately the meaning instead of transmitting symbols from the sender to the receiver.In this paper,we design a novel encoding ... Increasing research has focused on semantic communication,the goal of which is to convey accurately the meaning instead of transmitting symbols from the sender to the receiver.In this paper,we design a novel encoding and decoding semantic communication framework,which adopts the semantic information and the contextual correlations between items to optimize the performance of a communication system over various channels.On the sender side,the average semantic loss caused by the wrong detection is defined,and a semantic source encoding strategy is developed to minimize the average semantic loss.To further improve communication reliability,a decoding strategy that utilizes the semantic and the context information to recover messages is proposed in the receiver.Extensive simulation results validate the superior performance of our strategies over state-of-the-art semantic coding and decoding policies on different communication channels. 展开更多
关键词 Semantic information Semantic encoding method Context-based decoding method
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ANALYSIS OF SPECTRAL PHASE ENCODING OCDMA SYSTEM WITH PSEUDORANDOM CODING 被引量:2
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作者 张海滨 宋文涛 +1 位作者 黄培中 李荣玉 《Journal of Shanghai Jiaotong university(Science)》 EI 2002年第1期1-3,共3页
Multiple access interference (MAI) is the most serious interference in spectral phase encoding optical code division multiple access (SPE OCDMA) systems. This paper focuses on the behavior of MAI in SPE OCDMA systems ... Multiple access interference (MAI) is the most serious interference in spectral phase encoding optical code division multiple access (SPE OCDMA) systems. This paper focuses on the behavior of MAI in SPE OCDMA systems with pseudorandom coding. The statistical expectation of multi access interference (MAI) is derived and plotted. The results confirm that MAI can be suppressed effectively by pseudorandom coding with m sequences. 展开更多
关键词 optical CODE-DIVISION MULTIPLE-ACCESS (OCDMA) SPECTRAL phase encoding M-SEQUENCES MULTIPLE-ACCESS inteference (MAI)
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Analysis of Laser-encoding Remote-control Explosive System
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作者 JIANG Ben he 1, JIANG Zhi ling 2, HU Qing rong 3 (1.Institute of Infrared Remote Sensing, Shandong University, Jinan 250100, CHN 2. Department of Optics, Shandong University, Jinan 250100, CHN 3. Institute of Remote Sensing Applications CAS, B 《Semiconductor Photonics and Technology》 CAS 2002年第3期186-189,共4页
According to the requirements, an active infrared system is designed, which is composed of the emitting and receiving parts. The emitting part consists of a GaAs semiconductor laser device and binoculars optical syste... According to the requirements, an active infrared system is designed, which is composed of the emitting and receiving parts. The emitting part consists of a GaAs semiconductor laser device and binoculars optical system. A Si photodiode is selected as the receiving device, and a preamplifier circuit is designed to match the detector and further improve the signal to noise ratio. The laser encoding mode is utilized to enhance the anti disturbance. The theoretical analysis of this system is presented and a system prototype is made according to the requirement. The experimental results agree well with the theoretical prediction. 展开更多
关键词 LASER encoding mode INFRARED remote-control GAAS SEMICONDUCTOR LASER
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A Multi-Stream Scrambling and DNA Encoding Method Based Image Encryption
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作者 Nashat Salih Abdulkarim Alsandi Dilovan Asaad Zebari +4 位作者 Adel Al-Zebari Falah Y.H.Ahmed Mazin Abed Mohammed Marwan Albahar Abdulaziz Ali Albahr 《Computer Systems Science & Engineering》 SCIE EI 2023年第11期1321-1347,共27页
Information security has emerged as a key problem in encryption because of the rapid evolution of the internet and networks.Thus,the progress of image encryption techniques is becoming an increasingly serious issue an... Information security has emerged as a key problem in encryption because of the rapid evolution of the internet and networks.Thus,the progress of image encryption techniques is becoming an increasingly serious issue and considerable problem.Small space of the key,encryption-based low confidentiality,low key sensitivity,and easily exploitable existing image encryption techniques integrating chaotic system and DNA computing are purposing the main problems to propose a new encryption technique in this study.In our proposed scheme,a three-dimensional Chen’s map and a one-dimensional Logistic map are employed to construct a double-layer image encryption scheme.In the confusion stage,different scrambling operations related to the original plain image pixels are designed using Chen’s map.A stream pixel scrambling operation related to the plain image is constructed.Then,a block scrambling-based image encryption-related stream pixel scrambled image is designed.In the diffusion stage,two rounds of pixel diffusion are generated related to the confusing image for intra-image diffusion.Chen’s map,logistic map,and DNA computing are employed to construct diffusion operations.A reverse complementary rule is applied to obtain a new form of DNA.A Chen’s map is used to produce a pseudorandom DNA sequence,and then another DNA form is constructed from a reverse pseudorandom DNA sequence.Finally,the XOR operation is performed multiple times to obtain the encrypted image.According to the simulation of experiments and security analysis,this approach extends the key space,has great sensitivity,and is able to withstand various typical attacks.An adequate encryption effect is achieved by the proposed algorithm,which can simultaneously decrease the correlation between adjacent pixels by making it near zero,also the information entropy is increased.The number of pixels changing rate(NPCR)and the unified average change intensity(UACI)both are very near to optimal values. 展开更多
关键词 Grayscale image encryption stream scrambling-confusion DNA encoding XOR operation chaotic systems
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Geometric Calibration Method of Robot Based on Measurement System Including Position and Orientation Parameters
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作者 Deli Zhang Yu Zhu +1 位作者 Lu Yang Zhe Liu 《Journal of Harbin Institute of Technology(New Series)》 CAS 2023年第6期1-11,共11页
Industrial robot which can acquire high accuracy has been widely used in automatic assembly.Usually,the geometric parameter of industrial robot should be inspected during manufacturing and application.High precision m... Industrial robot which can acquire high accuracy has been widely used in automatic assembly.Usually,the geometric parameter of industrial robot should be inspected during manufacturing and application.High precision measurement equipment was utilized to acquire the position and orientation of robot’s end⁃effector,when calibrating the geometric parameter of robot.A kind of measurement system based on a draw⁃wire encoder was presented,since the current measurement equipment has some disadvantages,such as the cost and the requirements of working environment are high.According to this kind of measurement system,a sort of geometric calibration method of robot was presented including position and orientation parameters.The uncertain arc length of the cable length between robot end⁃effector and the measurement can be exactly acquired according to the position and orientation parameters.The pose⁃solving model of robot end⁃effector was associated with the kinematic model of robot,and robot’s geometric parameter can be computed by using the least⁃squares methods.Validate instance was conducted,the result showed that the optimal number of the calibration pose was 47 with little improvement in accuracy,even if increasing the number of calibration pose.Robot calibration experiment was performed and the results showed that the absolute accuracy of robot decreased from 4.32 mm to 0.87 mm after calibration,which improved the robot’s absolute accuracy effectively. 展开更多
关键词 Robot Calibration Industrial robot Geometric parameter identification Robot accuracy draw⁃wire encoder
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On the sampling strategies and models for measuring diffusion exchange with a double diffusion encoding sequence
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作者 Alfredo Ordinola Shan Cai +2 位作者 Peter Lundberg Ruiliang Bai Evren Ozarslan 《Magnetic Resonance Letters》 2023年第3期232-247,I0003,共17页
Water exchange between the different compartments of a heterogeneous specimen can be characterized via diffusion magnetic resonance imaging(dMRI).Many analysis frameworks using dMRI data have been proposed to describe... Water exchange between the different compartments of a heterogeneous specimen can be characterized via diffusion magnetic resonance imaging(dMRI).Many analysis frameworks using dMRI data have been proposed to describe exchange,often using a double diffusion encoding(DDE)stimulated echo sequence.Techniques such as diffusion exchange weighted imaging(DEWI)and the filter exchange and rapid exchange models,use a specific subset of the full space DDE signal.In this work,a general representation of the DDE signal was employed with different sampling schemes(namely constant b1,diagonal and anti-diagonal)from the data reduction models to estimate exchange.A near-uniform sampling scheme was proposed and compared with the other sampling schemes.The filter exchange and rapid exchange models were also applied to estimate exchange with their own subsampling schemes.These subsampling schemes and models were compared on both simulated data and experimental data acquired with a benchtop MR scanner.In synthetic data,the diagonal and near-uniform sampling schemes performed the best due to the consistency of their estimates with the ground truth.In experimental data,the shifted diagonal and near-uniform sampling schemes outperformed the others,yielding the most consistent estimates with the full space estimation.The results suggest the feasibility of measuring exchange using a general representation of the DDE signal along with variable sampling schemes.In future studies,algorithms could be further developed for the optimization of sampling schemes,as well as incorporating additional properties,such as geometry and diffusion anisotropy,into exchange frameworks. 展开更多
关键词 Diffusion MRI Water exchange Sampling schemes Double diffusion encoding
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The Dissemination of Chinese Tea Culture Based on Encoding/Decoding Theory
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作者 TAN Hao XIANYU Jing 《Journalism and Mass Communication》 2023年第1期45-49,共5页
Tea has a history of thousands of years in China and it plays an important role in the working-life and daily life of people.Tea culture rich in connotation is an important part of Chinese traditional culture,and its ... Tea has a history of thousands of years in China and it plays an important role in the working-life and daily life of people.Tea culture rich in connotation is an important part of Chinese traditional culture,and its existence and development are also of great significance to the diversified development of world culture.Based on Stuart Hall’s encoding/decoding theory,this paper analyzes the problems in the spreading of Chinese tea in and out of the country and provides solutions from the perspective of encoding,communication,and decoding.It is expected to provide a reference for the domestic and international dissemination of Chinese tea culture. 展开更多
关键词 tea culture encoding DECODING COMMUNICATION
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The Dissemination of Intangible Cultural Heritage Along Beijing-Hangzhou Canal Based on Encoding/Decoding Theory
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作者 TAN Hao XIANYU Jing 《Cultural and Religious Studies》 2023年第5期241-245,共5页
The Beijing-Hangzhou Grand Canal carries a wealth of Chinese cultural symbols,showing the lifestyle and wisdom of working people through ages.The preservation and inheritance of its intangible cultural heritage can he... The Beijing-Hangzhou Grand Canal carries a wealth of Chinese cultural symbols,showing the lifestyle and wisdom of working people through ages.The preservation and inheritance of its intangible cultural heritage can help to evoke cultural memories and cultural identification of the Canal and build cultural confidence.This paper applies Stuart Hall’s encoding/decoding theory to analyze the dissemination of intangible heritage tourism culture.On the basis of a practical study of the villages along the Beijing-Hangzhou Grand Canal,this paper analyses the problems in the transmission of its intangible cultural heritage and proposes specific methods to solve them in four processes,encoding,decoding,communication,and secondary encoding,in order to propose references for the transmission of intangible heritage culture at home and abroad. 展开更多
关键词 DISSEMINATION encoding DECODING intangible cultural heritage
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基于BE-MCNN模型的新闻评论情感分析方法
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作者 李文书 管平 《软件导刊》 2024年第3期1-7,共7页
实时新闻评论具有文本短、信息丰富、结构复杂等特点,情感分析难以准确捕捉其真实的情感倾向。为增强语义的特征信息,减少模型过拟合问题,提高新闻评论情感分析的准确性,提出一种融合BERT模型、Transformer En⁃coder与多尺度CNN模型的... 实时新闻评论具有文本短、信息丰富、结构复杂等特点,情感分析难以准确捕捉其真实的情感倾向。为增强语义的特征信息,减少模型过拟合问题,提高新闻评论情感分析的准确性,提出一种融合BERT模型、Transformer En⁃coder与多尺度CNN模型的新闻评论情感分析算法。首先,针对新闻评论长度较短、表达情绪观点内容较多的特点,使用BERT模型对新闻评论文本进行预训练,获得具有上下文信息的特征向量;其次,为解决模型过拟合问题,在BERT模型下游添加一层Transformer编码器;最后使用四通道双层CNN模型,通过组合不同大小尺寸的卷积核来提升模型分析新闻评论情感的性能。实验结果表明,该方法在两个新闻评论数据集上的准确率分别达到93.0%与96.4%;与不同模型的比较实验进一步证明了所提方法的有效性。 展开更多
关键词 情感分析 BERT模型 Transformer Encoder 多尺度CNN 新闻评论
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Continuous Pseudocolor Encoding of Thermal Image Display 被引量:6
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作者 李为 《Journal of Beijing Institute of Technology》 EI CAS 1997年第1期37-42,共6页
The visual features of continuous pseudocolor encoding is discussed and the optimiz- ing design algorithm of continuous pseudocolor scale is derived.The algorithm is restricting the varying range and direction of ligh... The visual features of continuous pseudocolor encoding is discussed and the optimiz- ing design algorithm of continuous pseudocolor scale is derived.The algorithm is restricting the varying range and direction of lightness,hue and saturation according to correlation and naturalness,automatically calculating the chromaticity coordinates of nodes in uniform color space to get the longest length of scale path,then interpolating points between nodes in equal color differences to obtain continuous pseudocolor scale with visual uniformity.When it was applied to the pseudocolor encoding of thermal image displays,the results showed that the correlation and the naturalness of original images and cognitive characteristics of target pattern were reserved well;the dynamic range of visual perception and the amount of visual information increased obviously;the contrast sensitivity of target identification improved;and the blindness of scale design were avoided. 展开更多
关键词 thermal image display pseudocolor encoding OPTIMIZATION color vision
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基于BERT与细粒度特征提取的数据法学问答系统
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作者 宋文豪 汪洋 +2 位作者 朱苏磊 张倩 吴晓燕 《上海师范大学学报(自然科学版中英文)》 2024年第2期211-216,共6页
首先利用bidirectional encoder representations from transformers(BERT)模型的强大的语境理解能力来提取数据法律文本的深层语义特征,然后引入细粒度特征提取层,依照注意力机制,重点关注文本中与数据法律问答相关的关键部分,最后对... 首先利用bidirectional encoder representations from transformers(BERT)模型的强大的语境理解能力来提取数据法律文本的深层语义特征,然后引入细粒度特征提取层,依照注意力机制,重点关注文本中与数据法律问答相关的关键部分,最后对所采集的法律问答数据集进行训练和评估.结果显示:与传统的多个单一模型相比,所提出的模型在准确度、精确度、召回率、F1分数等关键性能指标上均有提升,表明该系统能够更有效地理解和回应复杂的数据法学问题,为研究数据法学的专业人士和公众用户提供更高质量的问答服务. 展开更多
关键词 bidirectional encoder representations from transformers(BERT)模型 细粒度特征提取 注意力机制 自然语言处理(NLP)
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Detection and defending the XSS attack using novel hybrid stacking ensemble learning-based DNN approach
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作者 Muralitharan Krishnan Yongdo Lim +1 位作者 Seethalakshmi Perumal Gayathri Palanisamy 《Digital Communications and Networks》 SCIE CSCD 2024年第3期716-727,共12页
Existing web-based security applications have failed in many situations due to the great intelligence of attackers.Among web applications,Cross-Site Scripting(XSS)is one of the dangerous assaults experienced while mod... Existing web-based security applications have failed in many situations due to the great intelligence of attackers.Among web applications,Cross-Site Scripting(XSS)is one of the dangerous assaults experienced while modifying an organization's or user's information.To avoid these security challenges,this article proposes a novel,all-encompassing combination of machine learning(NB,SVM,k-NN)and deep learning(RNN,CNN,LSTM)frameworks for detecting and defending against XSS attacks with high accuracy and efficiency.Based on the representation,a novel idea for merging stacking ensemble with web applications,termed“hybrid stacking”,is proposed.In order to implement the aforementioned methods,four distinct datasets,each of which contains both safe and unsafe content,are considered.The hybrid detection method can adaptively identify the attacks from the URL,and the defense mechanism inherits the advantages of URL encoding with dictionary-based mapping to improve prediction accuracy,accelerate the training process,and effectively remove the unsafe JScript/JavaScript keywords from the URL.The simulation results show that the proposed hybrid model is more efficient than the existing detection methods.It produces more than 99.5%accurate XSS attack classification results(accuracy,precision,recall,f1_score,and Receiver Operating Characteristic(ROC))and is highly resistant to XSS attacks.In order to ensure the security of the server's information,the proposed hybrid approach is demonstrated in a real-time environment. 展开更多
关键词 Machine learning Deep neural networks Classification Stacking ensemble XSS attack URL encoding JScript/JavaScript Web security
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Delay and Energy Efficient Design of an On-Chip Bus with Repeaters Using a New Spatial and Temporal Encoding Technique
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作者 张庆利 王进祥 +1 位作者 喻明艳 叶以正 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第4期724-732,共9页
On-chip global buses in deep sub-micron designs consume significant amounts of energy and have large propagation delays. Thus, minimizing energy dissipation and propagation delay is an important design objective. In t... On-chip global buses in deep sub-micron designs consume significant amounts of energy and have large propagation delays. Thus, minimizing energy dissipation and propagation delay is an important design objective. In this paper, we propose a new spatial and temporal encoding approach for generic on-chip global buses with repeaters that enables higher performance while reducing peak energy and average energy. The proposed encoding approach exploits the benefits of a temporal encoding circuit and spatial bus-invert coding techniques to simultaneously eliminate opposite transitions on adjacent wires and reduce the number of self-transitions and coupling-transitions. In the design process of applying encoding techniques for reduced bus delay and energy, we present a repeater insertion design methodology to determine the repeater size and inter-repeater bus length, which minimizes the total bus energy dissipation while satisfying target delay and slew-rate constraints. This methodology is employed to obtain optimal energy versus delay trade-offs under slew-rate constraints for various encoding techniques. 展开更多
关键词 on-chip buses DELAY energy encoding REPEATERS
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Seeing at a distance with multicore fibers
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作者 Haogong Feng Xi Chen +4 位作者 Runze Zhu Yifeng Xiong Ye Chen Yanqing Lu Fei Xu 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第7期39-49,共11页
Images and videos provide a wealth of information for people in production and life.Although most digital information is transmitted via optical fiber,the image acquisition and transmission processes still rely heavil... Images and videos provide a wealth of information for people in production and life.Although most digital information is transmitted via optical fiber,the image acquisition and transmission processes still rely heavily on electronic circuits.The development of all-optical transmission networks and optical computing frameworks has pointed to the direction for the next generation of data transmission and information processing.Here,we propose a high-speed,low-cost,multiplexed parallel and one-piece all-fiber architecture for image acquisition,encoding,and transmission,called the Multicore Fiber Acquisition and Transmission Image System(MFAT).Based on different spatial and modal channels of the multicore fiber,fiber-coupled self-encoding,and digital aperture decoding technology,scenes can be observed directly from up to 1 km away.The expansion of capacity provides the possibility of parallel coded transmission of multimodal high-quality data.MFAT requires no additional signal transmitting and receiving equipment.The all-fiber processing saves the time traditionally spent on signal conversion and image pre-processing(compression,encoding,and modulation).Additionally,it provides an effective solution for 2D information acquisition and transmission tasks in extreme environments such as high temperatures and electromagnetic interference. 展开更多
关键词 long-distance fiber imaging image transmission parallel transmission all-optical encoding multicore fiber
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Taxonomy and phylogeny of the section Chaetoceros(Chaetocerotaceae,Bacillariophyta),with description of two new species
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作者 Xudan LU Mengyi ZHAI +1 位作者 Nina LUNDHOLM Yang LI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1286-1311,共26页
Chaetoceros Ehrenberg is one of the most diverse genera of planktonic diatoms.The species in section Chaetoceros are characterized by cells and setae having numerous chloroplasts and being widely distributed.However,t... Chaetoceros Ehrenberg is one of the most diverse genera of planktonic diatoms.The species in section Chaetoceros are characterized by cells and setae having numerous chloroplasts and being widely distributed.However,the delimitations of some species are problematic because of limited morphological information in the classical descriptions.Monoclonal strains of the section Chaetoceros were established,morphological features were studied using light and electron microscopy,and the hypervariable D 1-D 3 region of the nuclear ribosomal large subunit gene was sequenced to address phylogenetic relationships.Fifteen species belonging to the section Chaetoceros were recorded,including two new species,C.hainanensis sp.nov.and C.tridiscus sp.nov.Chaetoceros hainanensis was characterized by straight chains,narrowly lanceolate to hexagonal apertures,sibling setae diverging in nearly right angles,stipule-shaped spines on terminal setae and arrowhead-shaped spines on intercalary setae.C.tridiscus had short straight chains,narrowly lanceolate apertures,arrowhead-shaped spines and circular poroids arranged in a grid pattern on terminal and intercalary setae.The phylogenetic analyses revealed six groups formed by 19 species within the section Chaetoceros,which was found to be monophyletic.The subdivision of the section is still not well understood.The morphological characters within each group varied considerably and molecular information on more species are needed to enrich the phylogenetic profiling. 展开更多
关键词 morphology large subunit ribosomal RNA encoding gene(LSU) section Chaetoceros Chaetoceros hainanensis Chaetoceros tridiscus
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A Dual Domain Robust Reversible Watermarking Algorithm for Frame Grouping Videos Using Scene Smoothness
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作者 Yucheng Liang Ke Niu +1 位作者 Yingnan Zhang Yifei Meng 《Computers, Materials & Continua》 SCIE EI 2024年第6期5143-5174,共32页
The proposed robust reversible watermarking algorithm addresses the compatibility challenges between robustness and reversibility in existing video watermarking techniques by leveraging scene smoothness for frame grou... The proposed robust reversible watermarking algorithm addresses the compatibility challenges between robustness and reversibility in existing video watermarking techniques by leveraging scene smoothness for frame grouping videos.Grounded in the H.264 video coding standard,the algorithm first employs traditional robust watermark stitching technology to embed watermark information in the low-frequency coefficient domain of the U channel.Subsequently,it utilizes histogram migration techniques in the high-frequency coefficient domain of the U channel to embed auxiliary information,enabling successful watermark extraction and lossless recovery of the original video content.Experimental results demonstrate the algorithm’s strong imperceptibility,with each embedded frame in the experimental videos achieving a mean peak signal-to-noise ratio of 49.3830 dB and a mean structural similarity of 0.9996.Compared with the three comparison algorithms,the performance of the two experimental indexes is improved by 7.59%and 0.4%on average.At the same time,the proposed algorithm has strong robustness to both offline and online attacks:In the face of offline attacks,the average normalized correlation coefficient between the extracted watermark and the original watermark is 0.9989,and the average bit error rate is 0.0089.In the face of online attacks,the normalized correlation coefficient between the extracted watermark and the original watermark is 0.8840,and the mean bit error rate is 0.2269.Compared with the three comparison algorithms,the performance of the two experimental indexes is improved by 1.27%and 18.16%on average,highlighting the algorithm’s robustness.Furthermore,the algorithm exhibits low computational complexity,with the mean encoding and the mean decoding time differentials during experimental video processing being 3.934 and 2.273 s,respectively,underscoring its practical utility. 展开更多
关键词 Robust reversible watermarking scene smoothness dual-domain U channel H.264 encoding standard
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