期刊文献+
共找到18,437篇文章
< 1 2 250 >
每页显示 20 50 100
An Efficient Modelling of Oversampling with Optimal Deep Learning Enabled Anomaly Detection in Streaming Data
1
作者 R.Rajakumar S.Sathiya Devi 《China Communications》 SCIE CSCD 2024年第5期249-260,共12页
Recently,anomaly detection(AD)in streaming data gained significant attention among research communities due to its applicability in finance,business,healthcare,education,etc.The recent developments of deep learning(DL... Recently,anomaly detection(AD)in streaming data gained significant attention among research communities due to its applicability in finance,business,healthcare,education,etc.The recent developments of deep learning(DL)models find helpful in the detection and classification of anomalies.This article designs an oversampling with an optimal deep learning-based streaming data classification(OS-ODLSDC)model.The aim of the OSODLSDC model is to recognize and classify the presence of anomalies in the streaming data.The proposed OS-ODLSDC model initially undergoes preprocessing step.Since streaming data is unbalanced,support vector machine(SVM)-Synthetic Minority Over-sampling Technique(SVM-SMOTE)is applied for oversampling process.Besides,the OS-ODLSDC model employs bidirectional long short-term memory(Bi LSTM)for AD and classification.Finally,the root means square propagation(RMSProp)optimizer is applied for optimal hyperparameter tuning of the Bi LSTM model.For ensuring the promising performance of the OS-ODLSDC model,a wide-ranging experimental analysis is performed using three benchmark datasets such as CICIDS 2018,KDD-Cup 1999,and NSL-KDD datasets. 展开更多
关键词 anomaly detection deep learning hyperparameter optimization OVERSAMPLING SMOTE streaming data
下载PDF
The viscous strip approach to simplify the calculation of the surface acoustic wave generated streaming
2
作者 F.JAZINI DORCHEH M.GHASSEMI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第4期711-724,共14页
In recent decades,the importance of surface acoustic waves,as a biocompatible tool to integrate with microfluidics,has been proven in various medical and biological applications.The numerical modeling of acoustic stre... In recent decades,the importance of surface acoustic waves,as a biocompatible tool to integrate with microfluidics,has been proven in various medical and biological applications.The numerical modeling of acoustic streaming caused by surface acoustic waves in microchannels requires the effect of viscosity to be considered in the equations which complicates the solution.In this paper,it is shown that the major contribution of viscosity and the horizontal component of actuation is concentrated in a narrow region alongside the actuation boundary.Since the inviscid equations are considerably easier to solve,a division into the viscous and inviscid domains would alleviate the computational load significantly.The particles'traces calculated by this approximation are excellently alongside their counterparts from the completely viscous model.It is also shown that the optimum thickness for the viscous strip is about 9-fold the acoustic boundary layer thickness for various flow patterns and amplitudes of actuation. 展开更多
关键词 surface acoustic wave MICROFLUIDICS numerical simulation particle tracing acoustic streaming
下载PDF
Significance of Live Streaming in Shaping Business: A Critical Review and Analytical Study
3
作者 Nasir Uddin 《Social Networking》 2024年第3期35-43,共9页
With the rise of live streaming on social media, platforms like Facebook, Instagram, and YouTube have become powerful business tools. They enable users to share live videos, fostering direct connections between busine... With the rise of live streaming on social media, platforms like Facebook, Instagram, and YouTube have become powerful business tools. They enable users to share live videos, fostering direct connections between businesses and their customers. This critical literature review paper explores the impact of live streaming on businesses, focusing on its role in attracting and satisfying consumers by promoting products tailored to their needs and wants. It emphasizes live streaming’s crucial role in engaging customers, a key to business growth. The study also provides viable strategies for businesses to leverage live streaming for growth and customer engagement, underscoring its importance in the business landscape. 展开更多
关键词 Live streaming Social Media Business Impact Consumer Decision-Making Brand Community Interactive Marketing Facebook Live Instagram Live Product Reviews Online Consumer Behavior Self-Determination Theory (SDT) Live Video Marketing
下载PDF
Research on Current Situation and Legal Regulation of Cosmetics Live Streaming E-commerce in China
4
作者 Jiang Ying 《China Detergent & Cosmetics》 CAS 2024年第1期63-70,共8页
Analyze the compatibility between cosmetics and live streaming e-commerce from its own nature,marketing means and supply chain characteristics.According to the prominent problems,sort out the relationship between all ... Analyze the compatibility between cosmetics and live streaming e-commerce from its own nature,marketing means and supply chain characteristics.According to the prominent problems,sort out the relationship between all parties in the cosmetics live e-commerce industry chain.Combined with the latest regulatory policies of live streaming e-commerce and cosmetics,the responsibilities of different subjects in cosmetics live streaming e-commerce are summarized,and relevant suggestions and countermeasures are put forward for the standardization and development of live streaming e-commerce.Cosmetics brand owners are the first responsible persons for product quality.Anchors,as a mixed identity between intermediary,advertising spokesperson and operator,should bear stricter joint and several liability when recommending products related to consumers’health.If anchors fail to clearly identify themselves in the recommendation process,thus causing consumers to mistake them for the operator of the cosmetics,they should assume the obligations of the operator. 展开更多
关键词 COSMETICS live streaming e-commerce legal relationship responsibilities of parties
下载PDF
基于Spark Streaming的车辆电子围栏技术实现与应用
5
作者 吴宇昊 《西部交通科技》 2024年第5期177-179,共3页
文章提出一种基于Spark Streaming实时数据流处理框架,使用Kafka作为车辆轨迹数据的消息队列服务,结合拓扑关系判断算法射线法的车辆电子围栏技术。应用表明,该技术能够处理高吞吐率、强实时性的车辆动态数据,满足车辆动态精细化监管需求。
关键词 电子围栏 Spark streaming Kafka 射线法
下载PDF
A Study on the Factors Influencing Consumer Purchase Decision Under the Live-Streaming Sales Model
6
作者 Zhaoxia Zhang Yating Mo Yijun Xia 《Journal of Electronic Research and Application》 2024年第3期185-190,共6页
In recent years,with the rapid development and popularization of Internet information technology,many new media platforms have risen rapidly,and major e-commerce companies have begun to explore the mode of livestreami... In recent years,with the rapid development and popularization of Internet information technology,many new media platforms have risen rapidly,and major e-commerce companies have begun to explore the mode of livestreaming.Especially during the COVID-19 pandemic,due to the lockdown,live-streaming has become an important means of economic development in many places.Owing to its remarkable characteristics of timeliness,entertainment,and interactivity,it has become the latest and trendiest sales mode of e-commerce channels,reflecting huge economic potential and commercial value.This article analyzes two models and their characteristics of live-streaming sales from a practical perspective.Based on this,it outlines consumer purchasing decisions and the factors that affect consumer purchasing decisions under the live-streaming sales model.Finally,it discusses targeted suggestions for using the live-streaming sales model to expand the consumer market,hoping to promote the healthy and steady development of the live-streaming sales industry. 展开更多
关键词 Live streaming sales model CONSUMERS Purchase decisions Influencing factors
下载PDF
Machine Learning Based Classifiers for QoE Prediction Framework in Video Streaming over 5G Wireless Networks 被引量:1
7
作者 K.B.Ajeyprasaath P.Vetrivelan 《Computers, Materials & Continua》 SCIE EI 2023年第4期1919-1939,共21页
Recently,the combination of video services and 5G networks have been gaining attention in the wireless communication realm.With the brisk advancement in 5G network usage and the massive popularity of threedimensional ... Recently,the combination of video services and 5G networks have been gaining attention in the wireless communication realm.With the brisk advancement in 5G network usage and the massive popularity of threedimensional video streaming,the quality of experience(QoE)of video in 5G systems has been receiving overwhelming significance from both customers and service provider ends.Therefore,effectively categorizing QoE-aware video streaming is imperative for achieving greater client satisfaction.This work makes the following contribution:First,a simulation platform based on NS-3 is introduced to analyze and improve the performance of video services.The simulation is formulated to offer real-time measurements,saving the expensive expenses associated with real-world equipment.Second,A valuable framework for QoE-aware video streaming categorization is introduced in 5G networks based on machine learning(ML)by incorporating the hyperparameter tuning(HPT)principle.It implements an enhanced hyperparameter tuning(EHPT)ensemble and decision tree(DT)classifier for video streaming categorization.The performance of the ML approach is assessed by considering precision,accuracy,recall,and computation time metrics for manifesting the superiority of these classifiers regarding video streaming categorization.This paper demonstrates that our ML classifiers achieve QoE prediction accuracy of 92.59%for(EHPT)ensemble and 87.037%for decision tree(DT)classifiers. 展开更多
关键词 QoE-aware video streaming 5G networks wireless networks ensemble method
下载PDF
基于Spark Streaming的气象自动站实时流处理与存储系统 被引量:1
8
作者 马彬 李玉涛 许琪 《计算机技术与发展》 2023年第3期207-214,共8页
在当前大数据技术蓬勃发展的时代,人们对气象数据的实时处理、数据质量、数据存储及大规模查询等要求也越来越高。针对现有气象自动站数据业务落地环节多,任务处理耦合紧但系统部署分散等问题,文中基于Spark Streaming的流式计算框架,... 在当前大数据技术蓬勃发展的时代,人们对气象数据的实时处理、数据质量、数据存储及大规模查询等要求也越来越高。针对现有气象自动站数据业务落地环节多,任务处理耦合紧但系统部署分散等问题,文中基于Spark Streaming的流式计算框架,研究使用Flume解析收集自动站原始数据,在Spark Streaming中设计融入自动站数据质控算法,最终通过对分布式数据库存储的表设计,使气象自动站数据具备高效率、高质量、高可靠的应用服务能力。性能测试结果表明,基于Spark Streaming的气象自动站数据实时流处理与存储系统,数据从文件采集、解码、流处理至入库的全流程能够在秒级完成,TB级数据查询响应为毫秒级,加权查询为秒级,完全满足自动站数据业务应用需求,从而为进一步提高气象自动站数据质量与服务水平提供基础支撑。 展开更多
关键词 气象自动站数据 Spark streaming 实时处理 FLUME 分布式数据库
下载PDF
Distribution pattern of acoustic and streaming field during multi-source ultrasonic melt treatment process
9
作者 Xiao-gang Fang Qi Wei +5 位作者 Tian-yang Zhang Ji-guang Liu You-wen Yang Shu-lin Lü Shu-sen Wu Yi-qing Chen 《China Foundry》 SCIE CAS CSCD 2023年第5期452-460,共9页
The ultrasonic melt treatment(UMT)is widely used in the fields of casting and metallurgy.However,there are certain drawbacks associated with the conventional process of single-source ultrasonic(SSU)treatment,such as t... The ultrasonic melt treatment(UMT)is widely used in the fields of casting and metallurgy.However,there are certain drawbacks associated with the conventional process of single-source ultrasonic(SSU)treatment,such as the fast attenuation of energy and limited range of effectiveness.In this study,the propagation models of SSU and four-source ultrasonic(FSU)in Al melt were respectively established,and the distribution patterns of acoustic and streaming field during the ultrasonic treatment process were investigated by numerical simulation and physical experiments.The simulated results show that the effective cavitation zone is mainly located in a small spherical region surrounding the end of ultrasonic horn during the SSU treatment process.When the FSU is applied,the effective cavitation zone is obviously expanded in the melt.It increases at first and then decreases with increasing the vibration-source spacing(Lv)from 30 mm to 100 mm.Especially,when the Lv is 80 mm,the area of effective cavitation zone reaches the largest,indicating the best effect of cavitation.Moreover,the acoustic streaming level and flow pattern in the melt also change with the increase of Lv.When the Lv is 80 mm,both the average flow rate and maximum flow rate of the melt reach the highest,and the flow structure is more stable and uniform,with the typical morphological characteristics of angular vortex,thus significantly expanding the range of acoustic streaming.The accuracy of the simulation results was verified by physical experiments of glycerol aqueous solution and tracer particles. 展开更多
关键词 four-source ultrasound acoustic cavitation streaming field vibration-source spacing
下载PDF
Adaptive Learning Video Streaming with QoE in Multi-Home Heterogeneous Networks
10
作者 S.Vijayashaarathi S.NithyaKalyani 《Computer Systems Science & Engineering》 SCIE EI 2023年第9期2881-2897,共17页
In recent years,real-time video streaming has grown in popularity.The growing popularity of the Internet of Things(IoT)and other wireless heterogeneous networks mandates that network resources be carefully apportioned... In recent years,real-time video streaming has grown in popularity.The growing popularity of the Internet of Things(IoT)and other wireless heterogeneous networks mandates that network resources be carefully apportioned among versatile users in order to achieve the best Quality of Experience(QoE)and performance objectives.Most researchers focused on Forward Error Correction(FEC)techniques when attempting to strike a balance between QoE and performance.However,as network capacity increases,the performance degrades,impacting the live visual experience.Recently,Deep Learning(DL)algorithms have been successfully integrated with FEC to stream videos across multiple heterogeneous networks.But these algorithms need to be changed to make the experience better without sacrificing packet loss and delay time.To address the previous challenge,this paper proposes a novel intelligent algorithm that streams video in multi-home heterogeneous networks based on network-centric characteristics.The proposed framework contains modules such as Intelligent Content Extraction Module(ICEM),Channel Status Monitor(CSM),and Adaptive FEC(AFEC).This framework adopts the Cognitive Learning-based Scheduling(CLS)Module,which works on the deep Reinforced Gated Recurrent Networks(RGRN)principle and embeds them along with the FEC to achieve better performances.The complete framework was developed using the Objective Modular Network Testbed in C++(OMNET++),Internet networking(INET),and Python 3.10,with Keras as the front end and Tensorflow 2.10 as the back end.With extensive experimentation,the proposed model outperforms the other existing intelligentmodels in terms of improving the QoE,minimizing the End-to-End Delay(EED),and maintaining the highest accuracy(98%)and a lower Root Mean Square Error(RMSE)value of 0.001. 展开更多
关键词 Real-time video streaming IoT multi-home heterogeneous networks forward error coding deep reinforced gated recurrent networks QOE prediction accuracy RMSE
下载PDF
A Novel Outlier Detection with Feature Selection Enabled Streaming Data Classification
11
作者 R.Rajakumar S.Sathiya Devi 《Intelligent Automation & Soft Computing》 SCIE 2023年第2期2101-2116,共16页
Due to the advancements in information technologies,massive quantity of data is being produced by social media,smartphones,and sensor devices.The investigation of data stream by the use of machine learning(ML)approach... Due to the advancements in information technologies,massive quantity of data is being produced by social media,smartphones,and sensor devices.The investigation of data stream by the use of machine learning(ML)approaches to address regression,prediction,and classification problems have received consid-erable interest.At the same time,the detection of anomalies or outliers and feature selection(FS)processes becomes important.This study develops an outlier detec-tion with feature selection technique for streaming data classification,named ODFST-SDC technique.Initially,streaming data is pre-processed in two ways namely categorical encoding and null value removal.In addition,Local Correla-tion Integral(LOCI)is used which is significant in the detection and removal of outliers.Besides,red deer algorithm(RDA)based FS approach is employed to derive an optimal subset of features.Finally,kernel extreme learning machine(KELM)classifier is used for streaming data classification.The design of LOCI based outlier detection and RDA based FS shows the novelty of the work.In order to assess the classification outcomes of the ODFST-SDC technique,a series of simulations were performed using three benchmark datasets.The experimental results reported the promising outcomes of the ODFST-SDC technique over the recent approaches. 展开更多
关键词 streaming data classification outlier removal feature selection machine learning metaheuristics
下载PDF
基于效果定价模式的网络直播广告定价决策研究 被引量:2
12
作者 李莉 胡娇 《管理工程学报》 CSCD 北大核心 2024年第1期193-204,共12页
网络直播广告作为一种新型营销方式快速发展,优化直播广告运营主体努力水平及定价策略是一项值得深入研究的课题。本文基于广告投放效果的两种定价模式,构建了包含两个广告商和一个主播的网络直播广告定价决策模型,探索广告商与主播的... 网络直播广告作为一种新型营销方式快速发展,优化直播广告运营主体努力水平及定价策略是一项值得深入研究的课题。本文基于广告投放效果的两种定价模式,构建了包含两个广告商和一个主播的网络直播广告定价决策模型,探索广告商与主播的最优努力水平选择及广告定价策略。研究发现:CPW(cost per watch)定价模式下,广告商承担了消费者是否购买的不确定性风险,当消费者敏感性系数偏低时,广告商会提交较低的出价,且B/D两类广告商赢得竞拍的概率相等;对比CPW模式,在CPA(cost per action)定价模式下广告商的努力水平更低,且CPA定价模式中B型(品牌型)广告商赢得竞拍的概率更大,但赢得竞拍的广告商边际利润往往较低;与广告商相反,主播在CPA定价模式下的收益大于CPW,且随消费者敏感性系数的增加,两种定价模式下的收益差逐渐增大;CPW定价模式下预期观看直播的用户量和购买率均高于CPA,网络直播市场倾向于从CPW广告定价合同中获得较大收益。 展开更多
关键词 直播广告 定价模式 努力水平 广告决策
下载PDF
教育建筑的建筑教育——以本科四年级学校设计教学实践为例
13
作者 马进 叶凯威 《建筑技艺(中英文)》 2024年第1期73-78,共6页
从东南大学建筑学院本科四年级教育建筑设计系列课程的教学实践出发,对教育制度和空间模式相互关系展开深入研究。教育建筑设计系列课程通过立足社会问题的题目设置,职业建筑师的介入以及交叉学科的设计研究来指导教学实践,研究与总结... 从东南大学建筑学院本科四年级教育建筑设计系列课程的教学实践出发,对教育制度和空间模式相互关系展开深入研究。教育建筑设计系列课程通过立足社会问题的题目设置,职业建筑师的介入以及交叉学科的设计研究来指导教学实践,研究与总结其成果,对于发展更具有创新意识及职业性的建筑教育有重要的参考和借鉴意义。 展开更多
关键词 教育建筑 建筑教育 空间模式 STREAM中心
下载PDF
基于振荡射流的撞击流反应器流动及混合特性研究
14
作者 张建伟 刘名扬 +1 位作者 董鑫 冯颖 《流体机械》 CSCD 北大核心 2024年第5期47-54,共8页
为了研究振荡射流撞击流反应器内流场特性,利用SST k-ω湍流模型,建立振荡射流撞击流反应器数学模型且与试验进行对比。通过分析速度场、湍流动能分布、压力场和湍流黏度分布规律来研究撞击流反应器内部流动特性,揭示混合性能变化规律... 为了研究振荡射流撞击流反应器内流场特性,利用SST k-ω湍流模型,建立振荡射流撞击流反应器数学模型且与试验进行对比。通过分析速度场、湍流动能分布、压力场和湍流黏度分布规律来研究撞击流反应器内部流动特性,揭示混合性能变化规律。结果表明:在轴向上,速度、湍动能和压力呈多峰分布趋势且随着入口速度的上升而不断增大。在径向上,振荡器混合室内部涡旋中心受喷嘴小尺度涡旋干扰不断变化,从而影响流体振荡,使流场内产生4种流型。该反应器在35 s后混合均匀,混合强度达到0.95以上。研究结果丰富了流体振荡特性理论,为新型反应装置的开发提供理论参考。 展开更多
关键词 撞击流 振荡 流动特性 混合性能
下载PDF
二重情境:数字视听文化中的身份构建与认同疏离 被引量:1
15
作者 张梓轩 李政 《编辑之友》 北大核心 2024年第2期21-28,共8页
数字视听媒介及其文化的发展创造了新的情境,推动用户产生新的媒介实践,但也带来了新的问题和现象,即情境生成逻辑向流媒体用户让渡的转变、情境功能作为交往工具的偏移,以及情境秩序在去公共性过程中权力再结构化的取向。其中隐含着情... 数字视听媒介及其文化的发展创造了新的情境,推动用户产生新的媒介实践,但也带来了新的问题和现象,即情境生成逻辑向流媒体用户让渡的转变、情境功能作为交往工具的偏移,以及情境秩序在去公共性过程中权力再结构化的取向。其中隐含着情境之于用户身份构建的二重性:一方面,流媒体用户依据情境构建身份,身份的构建过程进一步激发了情境的创造;另一方面,这些被构建的身份呈现出去情境化的流动趋向,造成了身份与认同的疏离。对此,文章在厘清数字视听文化新情境特征的基础上,阐释流媒体用户基于身份的情境互动过程,以及身份认同疏离的成因及危机。更进一步,文章尝试将新媒介—新情境—新行为的线性模式延展为更具解释力的用户主导循环模式,并提出通过共识的凝聚、公共性的重拾和共同体的重建,推动数字视听文化的良序发展。 展开更多
关键词 数字视听文化 流媒体 媒介情境论 身份构建 认同疏离
下载PDF
非平衡数据流在线主动学习方法
16
作者 李艳红 任霖 +1 位作者 王素格 李德玉 《自动化学报》 EI CAS CSCD 北大核心 2024年第7期1389-1401,共13页
数据流分类是数据流挖掘领域一项重要研究任务,目标是从不断变化的海量数据中捕获变化的类结构.目前,几乎没有框架可以同时处理数据流中常见的多类非平衡、概念漂移、异常点和标记样本成本高昂问题.基于此,提出一种非平衡数据流在线主... 数据流分类是数据流挖掘领域一项重要研究任务,目标是从不断变化的海量数据中捕获变化的类结构.目前,几乎没有框架可以同时处理数据流中常见的多类非平衡、概念漂移、异常点和标记样本成本高昂问题.基于此,提出一种非平衡数据流在线主动学习方法(Online active learning method for imbalanced data stream,OALM-IDS).AdaBoost是一种将多个弱分类器经过迭代生成强分类器的集成分类方法,AdaBoost.M2引入了弱分类器的置信度,此类方法常用于静态数据.定义了基于非平衡比率和自适应遗忘因子的训练样本重要性度量,从而使AdaBoost.M2方法适用于非平衡数据流,提升了非平衡数据流集成分类器的性能.提出了边际阈值矩阵的自适应调整方法,优化了标签请求策略.将概念漂移程度融入模型构建过程中,定义了基于概念漂移指数的自适应遗忘因子,实现了漂移后的模型重构.在6个人工数据流和4个真实数据流上的对比实验表明,提出的非平衡数据流在线主动学习方法的分类性能优于其他5种非平衡数据流学习方法. 展开更多
关键词 主动学习 数据流分类 多类非平衡 概念漂移
下载PDF
非平衡概念漂移数据流主动学习方法
17
作者 李艳红 王甜甜 +1 位作者 王素格 李德玉 《自动化学报》 EI CAS CSCD 北大核心 2024年第3期589-606,共18页
数据流分类研究在开放、动态环境中如何提供更可靠的数据驱动预测模型,关键在于从实时到达且不断变化的数据流中检测并适应概念漂移.目前,为检测概念漂移和更新分类模型,数据流分类方法通常假设所有样本的标签都是已知的,这一假设在真... 数据流分类研究在开放、动态环境中如何提供更可靠的数据驱动预测模型,关键在于从实时到达且不断变化的数据流中检测并适应概念漂移.目前,为检测概念漂移和更新分类模型,数据流分类方法通常假设所有样本的标签都是已知的,这一假设在真实场景下是不现实的.此外,真实数据流可能表现出较高且不断变化的类不平衡比率,会进一步增加数据流分类任务的复杂性.为此,提出一种非平衡概念漂移数据流主动学习方法 (Active learning method for imbalanced concept drift data stream, ALM-ICDDS).定义基于多预测概率的样本预测确定性度量,提出边缘阈值矩阵的自适应调整方法,使得标签查询策略适用于类别数较多的非平衡数据流;提出基于记忆强度的样本替换策略,将难区分、少数类样本和代表当前数据分布的样本保存在记忆窗口中,提升新基分类器的分类性能;定义基于分类精度的基分类器重要性评价及更新方法,实现漂移后的集成分类器更新.在7个合成数据流和3个真实数据流上的对比实验表明,提出的非平衡概念漂移数据流主动学习方法的分类性能优于6种概念漂移数据流学习方法. 展开更多
关键词 数据流分类 主动学习 概念漂移 多类不平衡
下载PDF
融合Res3D、BiLSTM和注意力机制的羊只行为识别方法
18
作者 袁洪波 曹润柳 程曼 《农业机械学报》 EI CAS CSCD 北大核心 2024年第4期221-230,共10页
识别动物行为可以为疾病预防和合理喂养提供重要依据,从而有助于更好地关注动物的健康和福利。本文提出了一种融合三维残差卷积神经网络、双向长短期记忆网络和注意力机制的深度学习网络模型(AdRes3D-BiLSTM)。AdRes3D-BiLSTM模型可以... 识别动物行为可以为疾病预防和合理喂养提供重要依据,从而有助于更好地关注动物的健康和福利。本文提出了一种融合三维残差卷积神经网络、双向长短期记忆网络和注意力机制的深度学习网络模型(AdRes3D-BiLSTM)。AdRes3D-BiLSTM模型可以直接针对视频流进行识别,在AdRes3D部分引入了深度可分离卷积和注意力机制,不但减少了浮点运算量,提升了网络轻量化程度,还提高了时间和空间两个维度的特征提取能力;提取的特征被输入BiLSTM模块后,从前后2个方向对时序特征向量进行筛选和更新,最后对羊只行为进行准确识别。试验结果表明,AdRes3D-BiLSTM对羊只站立、躺卧、进食、行走和反刍5种行为的综合识别准确率达到了98.72%,帧速率达到52.79 f/s,模型内存占用量为28.03 MB。研究结果为基于视频流的动物行为识别提供了新的方法和思路。 展开更多
关键词 羊只 行为识别 视频流 Res3D BiLSTM 注意力机制
下载PDF
序列密码立方攻击研究进展综述
19
作者 田甜 戚文峰 《密码学报(中英文)》 CSCD 北大核心 2024年第1期145-158,共14页
立方攻击由Dinur和Shamir在2009年欧密会上首次提出,是一种高阶差分攻击和代数攻击.经过近十余年的研究,传统立方攻击不断发展,动态立方攻击、基于可分性的立方攻击、相关立方攻击相继提出,攻击思想不断丰富,攻击技术不断改进,逐渐成为... 立方攻击由Dinur和Shamir在2009年欧密会上首次提出,是一种高阶差分攻击和代数攻击.经过近十余年的研究,传统立方攻击不断发展,动态立方攻击、基于可分性的立方攻击、相关立方攻击相继提出,攻击思想不断丰富,攻击技术不断改进,逐渐成为针对基于非线性反馈移位寄存器的序列密码算法的重要攻击方法.特别地,立方攻击自2009年提出以来一直是国际轻量级序列密码标准Trivium最有效的密钥恢复攻击,动态立方攻击攻破了全轮Grain-128算法,Kreyvium、Grain-128AEAD、ACORN这些基于非线性反馈移位寄存器的序列密码算法都可以用立方攻击进行有效分析.本文介绍了立方攻击的基本原理和攻击方法,综述了实验立方攻击、基于可分性立方攻击、立方集构造、动态立方攻击、相关立方攻击等方面的研究进展. 展开更多
关键词 立方攻击 可分性 MILP 序列密码 Trivium
下载PDF
黄河流域矿产资源开发-经济-环境耦合协调发展及时空演化研究
20
作者 王成军 杨倩 +2 位作者 冯涛 杜传甲 张炳林 《资源与产业》 2024年第4期10-20,共11页
黄河流域长期过量的矿产资源开发导致的生态退化和环境问题日益恶化,如何在环境约束下促进经济高质量发展已经成为黄河流域的重要课题。首先,将9个位于黄河流域的省份作为研究对象,选取矿产资源开发、经济、环境3个子系统的7个二级指标... 黄河流域长期过量的矿产资源开发导致的生态退化和环境问题日益恶化,如何在环境约束下促进经济高质量发展已经成为黄河流域的重要课题。首先,将9个位于黄河流域的省份作为研究对象,选取矿产资源开发、经济、环境3个子系统的7个二级指标和28个三级指标,构建黄河流域矿产资源开发、经济和环境耦合协调评价体系,基于2011—2021年各省份面板数据,运用熵权法对该区域各省三大系统的综合发展水平进行评价。其次,构建黄河流域耦合协调度模型研究3个子系统之间的耦合协调关系,并使用ArcGIS来研究其时空格局上的演变过程。研究发现:1)2011—2021年各省综合发展指数不断提高,整体呈现为下游高于中游高于上游,上、中、下游地区综合发展指数增长率分别为59.2%、51.9%、60.9%;2)2011—2021年,耦合指数处于高值的省份数量逐渐增加,处于低值的省份数量逐渐减少,中、下游地区耦合指数水平均高于全流域的平均水平;3)从时间分布上来看,2011—2021年黄河流域个别省份处于协调状态以上,但仍有省份协调表现较差,三者的耦合协调度已接近失衡,但仍在稳定的向勉强协调发展,仍有很大空间;4)从空间格局来看,各省份协调指数均稳步增长,到2021年,处于协调状态的省份有8个,占所有省份的88.89%,且呈现“东高西低”(下游协调指数高于上游)的空间分布及省份间的两极分化现象。该研究结果可为黄河流域的环境保护和治理及区域间经济协调发展提供理论支持。基于研究,提出促进黄河流域协调发展的对策建议:重点关注地区之间的发展不平衡问题;加强科学规划建设;合理开发利用矿产资源,加强生态环境治理。 展开更多
关键词 黄河流域 耦合协调度 熵权法 时空演化
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部