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Enhancing IoT Resilience at the Edge:A Resource-Efficient Framework for Real-Time Anomaly Detection in Streaming Data
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作者 Kirubavathi G. Arjun Pulliyasseri +5 位作者 Aswathi Rajesh Amal Ajayan Sultan Alfarhood Mejdl Safran Meshal Alfarhood Jungpil Shin 《Computer Modeling in Engineering & Sciences》 2025年第6期3005-3031,共27页
The exponential expansion of the Internet of Things(IoT),Industrial Internet of Things(IIoT),and Transportation Management of Things(TMoT)produces vast amounts of real-time streaming data.Ensuring system dependability... The exponential expansion of the Internet of Things(IoT),Industrial Internet of Things(IIoT),and Transportation Management of Things(TMoT)produces vast amounts of real-time streaming data.Ensuring system dependability,operational efficiency,and security depends on the identification of anomalies in these dynamic and resource-constrained systems.Due to their high computational requirements and inability to efficiently process continuous data streams,traditional anomaly detection techniques often fail in IoT systems.This work presents a resource-efficient adaptive anomaly detection model for real-time streaming data in IoT systems.Extensive experiments were carried out on multiple real-world datasets,achieving an average accuracy score of 96.06%with an execution time close to 7.5 milliseconds for each individual streaming data point,demonstrating its potential for real-time,resourceconstrained applications.The model uses Principal Component Analysis(PCA)for dimensionality reduction and a Z-score technique for anomaly detection.It maintains a low computational footprint with a sliding window mechanism,enabling incremental data processing and identification of both transient and sustained anomalies without storing historical data.The system uses a Multivariate Linear Regression(MLR)based imputation technique that estimates missing or corrupted sensor values,preserving data integrity prior to anomaly detection.The suggested solution is appropriate for many uses in smart cities,industrial automation,environmental monitoring,IoT security,and intelligent transportation systems,and is particularly well-suited for resource-constrained edge devices. 展开更多
关键词 Anomaly detection streaming data IOT IIoT TMoT REAL-TIME LIGHTWEIGHT modeling
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Modeling and Performance Evaluation of Streaming Data Processing System in IoT Architecture
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作者 Feng Zhu Kailin Wu Jie Ding 《Computers, Materials & Continua》 2025年第5期2573-2598,共26页
With the widespread application of Internet of Things(IoT)technology,the processing of massive realtime streaming data poses significant challenges to the computational and data-processing capabilities of systems.Alth... With the widespread application of Internet of Things(IoT)technology,the processing of massive realtime streaming data poses significant challenges to the computational and data-processing capabilities of systems.Although distributed streaming data processing frameworks such asApache Flink andApache Spark Streaming provide solutions,meeting stringent response time requirements while ensuring high throughput and resource utilization remains an urgent problem.To address this,the study proposes a formal modeling approach based on Performance Evaluation Process Algebra(PEPA),which abstracts the core components and interactions of cloud-based distributed streaming data processing systems.Additionally,a generic service flow generation algorithmis introduced,enabling the automatic extraction of service flows fromthe PEPAmodel and the computation of key performance metrics,including response time,throughput,and resource utilization.The novelty of this work lies in the integration of PEPA-based formal modeling with the service flow generation algorithm,bridging the gap between formal modeling and practical performance evaluation for IoT systems.Simulation experiments demonstrate that optimizing the execution efficiency of components can significantly improve system performance.For instance,increasing the task execution rate from 10 to 100 improves system performance by 9.53%,while further increasing it to 200 results in a 21.58%improvement.However,diminishing returns are observed when the execution rate reaches 500,with only a 0.42%gain.Similarly,increasing the number of TaskManagers from 10 to 20 improves response time by 18.49%,but the improvement slows to 6.06% when increasing from 20 to 50,highlighting the importance of co-optimizing component efficiency and resource management to achieve substantial performance gains.This study provides a systematic framework for analyzing and optimizing the performance of IoT systems for large-scale real-time streaming data processing.The proposed approach not only identifies performance bottlenecks but also offers insights into improving system efficiency under different configurations and workloads. 展开更多
关键词 System modeling performance evaluation streaming data process IoT system PEPA
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Environment-aware streaming media transmission method in high-speed mobile networks
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作者 Jia Guo Jinqi Zhu +3 位作者 Xiang Li Bowen Sun Qian Gao Weijia Feng 《Digital Communications and Networks》 2025年第4期991-1005,共15页
With technological advancements,high-speed rail has emerged as a prevalent mode of transportation.During travel,passengers exhibit a growing demand for streaming media services.However,the high-speed mobile networks e... With technological advancements,high-speed rail has emerged as a prevalent mode of transportation.During travel,passengers exhibit a growing demand for streaming media services.However,the high-speed mobile networks environment poses challenges,including frequent base station handoffs,which significantly degrade wireless network transmission performance.Improving transmission efficiency in high-speed mobile networks and optimizing spatiotemporal wireless resource allocation to enhance passengers’media experiences are key research priorities.To address these issues,we propose an Adaptive Cross-Layer Optimization Transmission Method with Environment Awareness(ACOTM-EA)tailored for high-speed rail streaming media.Within this framework,we develop a channel quality prediction model utilizing Kalman filtering and an algorithm to identify packet loss causes.Additionally,we introduce a proactive base station handoffstrategy to minimize handoffrelated disruptions and optimize resource distribution across adjacent base stations.Moreover,this study presents a wireless resource allocation approach based on an enhanced genetic algorithm,coupled with an adaptive bitrate selection mechanism,to maximize passenger Quality of Experience(QoE).To evaluate the proposed method,we designed a simulation experiment and compared ACOTM-EA with established algorithms.Results indicate that ACOTM-EA improves throughput by 11%and enhances passengers’media experience by 5%. 展开更多
关键词 High-speed mobile networks streaming media Environment-aware Kalman filtering Resource allocation
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Ultrafast no-wash bioassay based on gold nanoparticles and enhanced by acoustic streaming
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作者 Shuting Pan Xianwu Ke +7 位作者 Rui You Yanyan Wang Xian Chen Xiaotian Shen Bohua Liu Chongling Sun Wei Pang Xuexin Duan 《Nanotechnology and Precision Engineering》 2025年第2期77-85,共9页
No-wash bioassays based on nanoparticles are used widely in biochemical procedures because of their responsive sensing and no need forwashing processes.Essential for no-wash biosensing are the interactions between nan... No-wash bioassays based on nanoparticles are used widely in biochemical procedures because of their responsive sensing and no need forwashing processes.Essential for no-wash biosensing are the interactions between nanoparticles and biomolecules,but it is challenging toachieve controlled bioconjugation of molecules on nanomaterials.Reported here is a way to actively improve nanoparticle-based no-washbioassays by enhancing the binding between biomolecules and gold nanoparticles via acoustic streaming generated by a gigahertz piezoelectricnanoelectromechanical resonator.Tunable micro-vortices are generated at the device-liquid interface,thereby accelerating the internalcirculating flow of the solution,bypassing the diffusion limitation,and thus improving the binding between the biomolecules and goldnanoparticles.Combined with fluorescence quenching,an enhanced and ultrafast no-wash biosensing assay is realized for specific proteins.The sensing method presented here is a versatile tool for different types of biomolecule detection with high efficiency and simplicity. 展开更多
关键词 Acoustic streaming Gold nanoparticles Fluorescence quenching BIOSENSING
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基于嵌入式Linux系统的Smooth Streaming流媒体设计与实现
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作者 刘刚 《信息与电脑》 2025年第12期139-142,共4页
随着视频播放需求的爆发性增长,在嵌入式硬件资源受限的情况下,如何保障视频流畅播放成为亟待解决的问题。文章设计并实现了一种基于嵌入式Linux系统的Smooth Streaming流媒体解决方案。基于微软公司Smooth Streaming流媒体技术的机制,... 随着视频播放需求的爆发性增长,在嵌入式硬件资源受限的情况下,如何保障视频流畅播放成为亟待解决的问题。文章设计并实现了一种基于嵌入式Linux系统的Smooth Streaming流媒体解决方案。基于微软公司Smooth Streaming流媒体技术的机制,提出分层设计方案,包含流媒体解析模块、流媒体解密模块、流媒体下载模块和流媒体动态码率控制模块。方案在嵌入式Linux平台完成代码开发与系统测试,已成功应用于商用产品。测试结果表明,在硬件资源受限条件下,该方案可实现视频的流畅播放,且系统可长期稳定运行。 展开更多
关键词 嵌入式LINUX Smooth streaming 流媒体
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A Review of Content Marketing’s Influence on Consumers’ Purchase Intention in Live-streaming E-commerce
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作者 Yuan Wang 《Proceedings of Business and Economic Studies》 2025年第1期55-59,共5页
In the contemporary digital landscape,the proliferation of information has led to an increasing diversity of channels through which consumers obtain information,resulting in a gradual transformation of shopping habits... In the contemporary digital landscape,the proliferation of information has led to an increasing diversity of channels through which consumers obtain information,resulting in a gradual transformation of shopping habits.Consumers now frequently rely on external sources to make well-informed purchasing decisions,leading to the emergence of live shopping as a prominent avenue for gathering product information and completing transactions.E-commerce live streaming has experienced rapid growth,leveraging its ability to generate traffic and capture consumer attention.The integration of content and live streaming not only meets users’psychological needs but also facilitates seamless communication between buyers and sellers.From the perspective of content marketing typologies,this paper examines content marketing across three key dimensions:informational content,entertainment content,and emotional content.It further explores the impact of content marketing on consumers’purchase intentions within the context of e-commerce live streaming. 展开更多
关键词 Content marketing E-commerce live streaming Consumer purchase intention
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An Efficient Modelling of Oversampling with Optimal Deep Learning Enabled Anomaly Detection in Streaming Data 被引量:2
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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
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The viscous strip approach to simplify the calculation of the surface acoustic wave generated streaming
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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
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Significance of Live Streaming in Shaping Business: A Critical Review and Analytical Study
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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
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Research on Current Situation and Legal Regulation of Cosmetics Live Streaming E-commerce in China
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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
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基于Spark Streaming的车辆电子围栏技术实现与应用
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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
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A Study on the Factors Influencing Consumer Purchase Decision Under the Live-Streaming Sales Model
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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
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浙江遂昌花臭蛙的两性异形和雌性生育力 被引量:1
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作者 樊晓丽 毛岳松 +3 位作者 鲁成朴 成金强 李金阳 林植华 《生态科学》 北大核心 2025年第1期51-57,共7页
测量了栖息在浙江遂昌山涧溪流生境中的200只花臭蛙(Odorrana schmackeri)的14个形态特征的性别间差异和雌性个体怀卵量。结果显示,繁殖期花臭蛙雌性个体的数量显著少于雄性个体,雌性个体的体长显著大于雄性个体。单因素协方差分析表明... 测量了栖息在浙江遂昌山涧溪流生境中的200只花臭蛙(Odorrana schmackeri)的14个形态特征的性别间差异和雌性个体怀卵量。结果显示,繁殖期花臭蛙雌性个体的数量显著少于雄性个体,雌性个体的体长显著大于雄性个体。单因素协方差分析表明,特定体长雄蛙的眼径、耳径和前臂宽均显著大于雌蛙,特定体长雌蛙的前肢长和后肢长均显著大于雄蛙,其他局部特征的两性间差异不显著。所检测花臭蛙雌性个体30只,其中怀卵个体16只,怀卵数量在1119-2636粒之间,平均为1665粒。线性回归分析表明,花臭蛙雌性个体的怀卵数量与体长和体重回归关系显著。进一步偏相关分析表明,花臭蛙雌性个体的怀卵数量与体重呈显著的正相关,与体长相关不显著。花臭蛙属于个体大小偏向雌性的两性异形,是生育力选择和生活史策略综合影响所致;雌蛙和雄蛙有选择性地驱使四肢长度、感觉器官和前臂宽等关键局部形态特征向大方向进化,这是对山涧溪流繁殖场选择的适应。 展开更多
关键词 花臭蛙 两性异形 生育力选择 年龄 山涧
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面向粮食安全政策咨询的情报智库服务模式与实现路径研究 被引量:1
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作者 张海涛 刘彦辉 +1 位作者 周红磊 栾宇 《情报理论与实践》 北大核心 2025年第1期31-41,共11页
[目的/意义]以情报学手段保障国家粮食安全,提升智库服务专业性的同时,推动图情机构的服务创新与升级。[方法/过程]通过网络调研与访谈总结现有智库在支撑粮食安全政策咨询中的不足,解析服务任务,基于多源流理论提出面向粮食安全政策咨... [目的/意义]以情报学手段保障国家粮食安全,提升智库服务专业性的同时,推动图情机构的服务创新与升级。[方法/过程]通过网络调研与访谈总结现有智库在支撑粮食安全政策咨询中的不足,解析服务任务,基于多源流理论提出面向粮食安全政策咨询的情报智库服务模式与实现路径。[结果/结论]研究设计的情报智库服务模式能够容纳粮食安全问题的复杂逻辑关系,并通过内容问答、简报服务与方案服务的方式响应政策咨询需求,促进科学化与高质量智库服务实现。 展开更多
关键词 粮食安全 政策咨询 情报智库 服务模式 多源流理论
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高中阶段普职分流:误解、事实与愿景 被引量:4
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作者 田志磊 薛懿 殷利 《华东师范大学学报(教育科学版)》 北大核心 2025年第2期105-118,共14页
近年来,由于大众对普职分流存在误解,教育焦虑在社会上不断产生和蔓延。在描述普职分流的事实和特征的基础上,本文重新审视了社会上对普职分流的批判。过去二十年,我国高中阶段普职比经历了过山车般的剧烈变化,但一直大于1∶1,当前高中... 近年来,由于大众对普职分流存在误解,教育焦虑在社会上不断产生和蔓延。在描述普职分流的事实和特征的基础上,本文重新审视了社会上对普职分流的批判。过去二十年,我国高中阶段普职比经历了过山车般的剧烈变化,但一直大于1∶1,当前高中阶段至少六成甚至三分之二的孩子在普通高中就读,个别省份这一比例已近八成。微观数据表明,家庭背景对普职分流重要但并非桎梏,学业成绩才是主导性因素;大城市家庭和多子女家庭在普职分流中面临更大的压力;男孩在普职分流中表现逊色于女孩。随后,本文围绕普职分流的主流批判提供了少数支持、多数相悖的证据。最后,基于对普职分流的实证分析,本文探讨了我国普职协调未来的可能路径。 展开更多
关键词 普职分流 教育焦虑 分轨制 制造业
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委托代理关系下品牌商网络直播营销激励机制设计 被引量:2
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作者 周驰 李赫 于静 《中国管理科学》 北大核心 2025年第4期265-274,共10页
数字经济的迅速发展促进了网络直播在营销中的广泛应用,越来越多的品牌商委托电商主播为其提供商品推荐服务。本文构建了单一品牌商与风险规避的电商主播构成的委托代理模型,其中品牌商与主播分别为委托方与代理方,通过求解不同信息状... 数字经济的迅速发展促进了网络直播在营销中的广泛应用,越来越多的品牌商委托电商主播为其提供商品推荐服务。本文构建了单一品牌商与风险规避的电商主播构成的委托代理模型,其中品牌商与主播分别为委托方与代理方,通过求解不同信息状态下品牌商的最优激励合同以及主播的最优推荐努力水平,分析消费者偏好和主播推荐努力水平的信息价值,探究消费者偏好、主播的风险规避程度和市场需求的不确定性对最优合同的影响。结论表明:当主播的推荐努力水平可观测时,品牌商设计仅含直播佣金的最优激励合同,以获取主播的全部价值;当推荐努力水平不可观测时,最优激励合同包括直播佣金与收入分成两部分,此时风险规避程度的增大会降低主播的推荐努力水平,导致品牌商利润降低,从而降低最优激励合同中的收入分成。此外,不对称的消费者偏好信息在努力水平可观测时不影响品牌商利润,而在努力水平不可观测时可能增加品牌商利润,且具有努力水平信息优势的品牌商往往获利更多。 展开更多
关键词 委托代理模型 直播营销 推荐服务 激励合同 信息不对称
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直播间里的“夕阳红”:乡村老年人数字接入中的劳动实践与关系重塑 被引量:2
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作者 徐婧 曾维珊 《新闻与传播评论》 北大核心 2025年第2期20-32,共13页
在当前老龄化与数字化叠加的社会背景下,中国老年人群体如何无障碍地接入数字社会并参与数字实践,是实现社会主义现代化的应有之意。旨在破除老年人数字劳动问题的固有预设,摆脱数字劳动“异化”与“剥削”的简化解释路径。回归劳动者... 在当前老龄化与数字化叠加的社会背景下,中国老年人群体如何无障碍地接入数字社会并参与数字实践,是实现社会主义现代化的应有之意。旨在破除老年人数字劳动问题的固有预设,摆脱数字劳动“异化”与“剥削”的简化解释路径。回归劳动者主体性与能动性的视角,勾勒出即符合现实,又具有建设意义的老年人数字接入及数字劳动图景。以网络直播间为线上田野,使用非参与式观察和半结构式访谈收集经验材料。研究发现,在完成数字接入的老年人中,呈现出“玩转直播间”的多元数字实践,并通过“深层表演”建构出特殊的社会关系想象。透过老年主播的自我叙事,理解老年群体数字劳动的多重意义:他们并非全然被动断连的弱者。我们理应看到数字接入为老年群体带来的社会参与感,创造出证明自我价值的新空间,并为其晚年时光注入了追逐生命意义的动力及价值。 展开更多
关键词 直播 老年主播 劳动 代际 乡村
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全媒体时代主流媒体系统性变革:内在逻辑、理论支点与实践进路 被引量:6
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作者 李彪 陈智睿 《编辑之友》 北大核心 2025年第1期11-18,共8页
主流媒体系统性变革是全媒体传播体系建设在进入新阶段后的整体谋划,事关主流媒体重新获得舆论主导权的核心问题,是媒体融合纵深发展的最新表征。主流媒体系统性变革不是突然出现的顶层设计,而是具备战略流、政策流、问题流和主体流四... 主流媒体系统性变革是全媒体传播体系建设在进入新阶段后的整体谋划,事关主流媒体重新获得舆论主导权的核心问题,是媒体融合纵深发展的最新表征。主流媒体系统性变革不是突然出现的顶层设计,而是具备战略流、政策流、问题流和主体流四个层次的应然概念。文章系统梳理了主流媒体系统性变革的理论支点,包括对我国主流媒体相关研究议程进行梳理,以及对系统性变革从分散性到系统性、层次性到生态性、依赖性到自主性的理论逻辑进行阐述,展现主流媒体系统性变革的紧迫性与必然性。最后,从全局性站位、系统化思维、精准化传播以及智能化技术四个方面探讨了推进主流媒体系统性变革的实践进路。 展开更多
关键词 主流媒体 系统性变革 多源流理论 全媒体传播体系
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黏质砂土地球物理与水文化学特性综合动态测量系统 被引量:1
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作者 柳建新 曾加佳 +3 位作者 谢静 陈儒军 郭荣文 陈杭 《地球物理学报》 北大核心 2025年第7期2754-2768,共15页
离子吸附型稀土矿是关乎我国稀土关键矿产国际竞争优势和资源战略安全的重要矿床类型.为探究离子吸附型矿物的频谱激电响应和流动电位响应特征,本文设计并搭建了一套可同步测量黏质砂土地球物理与水文化学特性的流动系统.该系统基于离... 离子吸附型稀土矿是关乎我国稀土关键矿产国际竞争优势和资源战略安全的重要矿床类型.为探究离子吸附型矿物的频谱激电响应和流动电位响应特征,本文设计并搭建了一套可同步测量黏质砂土地球物理与水文化学特性的流动系统.该系统基于离子吸附型稀土矿成矿理论和双电层电化学原理,集成电法探测和水文化学测量功能,可测试由不同盐浓度溶液饱和的黏土砂样在不同水力梯度条件下的流动电势差、复电导率和孔隙水压力,并收集孔隙液体进行化学分析.本文基于该系统开展了系列测量工作,包括自来水和不同盐浓度溶液的复电导率以及由不同盐浓度溶液饱和的不同黏质砂土样本的复电导率并计算砂样的地层因子.此外在不同水力梯度条件下同时测量孔隙水压力值和流动电势差,计算砂样的水力及电性参数.实验结果表明,自来水复电导率测量结果与前人研究结论相似、不同盐浓度溶液的复电导率幅值测量结果与电导率仪的测量结果具有较强线性相关、饱和石英砂复电导率测量结果估计的砂样地层因子在理论范围内、不同盐浓度溶液和不同黏土含量的土样复电导率测量结果与前人研究结论相似;饱和情况下,不同盐浓度溶液测量的平均电势差和平均流量随平均压力差呈线性变化,由测量结果评估的土样饱和水力传导率及流动电位耦合系数在理论范围内.相关实验结论验证了该装置系统的有效性和稳定性,证明该流动系统测量离子吸附型稀土矿水文化学特性与地球物理响应的可行性,为进一步基于离子吸附型稀土矿的成矿富集机理探究其成矿化学特性和流动电位信号与激电响应之间的联系以及潜在勘探技术奠定了实验基础. 展开更多
关键词 离子吸附型稀土矿 频谱激电 流动电位 物理实验
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多源流理论视角下拔尖创新医学人才政策动力分析 被引量:2
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作者 万晓文 黄蓉 +4 位作者 盛文彬 曾程 陈小可 曹晓辉 肖永平 《中国医院》 北大核心 2025年第3期83-87,共5页
运用多源流理论分析框架探讨拔尖创新医学人才政策的演进动力和演进过程,提出政策优化建议。研究认为,医疗需求增长、高层次医疗人才缺乏和医药创新能力不足是推动拔尖创新医学人才政策的问题源流;专家学者的建议、医学教育试点成果的... 运用多源流理论分析框架探讨拔尖创新医学人才政策的演进动力和演进过程,提出政策优化建议。研究认为,医疗需求增长、高层次医疗人才缺乏和医药创新能力不足是推动拔尖创新医学人才政策的问题源流;专家学者的建议、医学教育试点成果的支撑和利益相关者的推动是推动拔尖创新医学人才政策的政策源流;党和政府的执政理念和历史经验、公众舆论是推动拔尖创新医学人才政策的政治源流;三流交汇开启政策之窗。基于分析发现,存在拔尖创新医学人才定义界定不清晰、政策目标不清晰、政策研究不足及政策推广不足等问题,提出关注问题源流,明确政策界定;优化政策源流,拓展建议渠道;紧跟政治源流,发挥推广作用的优化建议。 展开更多
关键词 医学人才 多源流 拔尖创新 医学教育
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