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Data Fusion Algorithm Based on Fuzzy Sets and D-S Theory of Evidence
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作者 Guangzhe Zhao Aiguo Chen +1 位作者 Guangxi Lu Wei Liu 《清华大学学报自然科学版(英文版)》 EI CAS CSCD 2020年第1期12-19,共8页
In cyber-physical systems, multidimensional data fusion is an important method to achieve comprehensive evaluation decisions and reduce data redundancy. In this paper, a data fusion algorithm based on fuzzy set theory... In cyber-physical systems, multidimensional data fusion is an important method to achieve comprehensive evaluation decisions and reduce data redundancy. In this paper, a data fusion algorithm based on fuzzy set theory and Dempster-Shafer(D-S) evidence theory is proposed to overcome the shortcomings of the existing decision-layer multidimensional data fusion algorithms. The basic probability distribution of evidence is determined based on fuzzy set theory and attribute weights, and the data fusion of attribute evidence is combined with the credibility of sensor nodes in a cyber-physical systems network. Experimental analysis shows that the proposed method has obvious advantages in the degree of the differentiation of the results. 展开更多
关键词 data FUSION FUZZY SETS Dempster-Shafer(D-S) THEORY
A Novel Transparent and Auditable Fog-Assisted Cloud Storage with Compensation Mechanism
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作者 Donghyun Kim Junggab Son +3 位作者 Daehee Seo Yeojin Kim Hyobin Kim Jung Taek Seo 《清华大学学报自然科学版(英文版)》 EI CAS CSCD 2020年第1期28-43,共16页
This paper introduces a new fog-assisted cloud storage which can achieve much higher throughput compared to the traditional cloud-only storage architecture by reducing the traffics toward the cloud storage. The fog-st... This paper introduces a new fog-assisted cloud storage which can achieve much higher throughput compared to the traditional cloud-only storage architecture by reducing the traffics toward the cloud storage. The fog-storage service providers are transparency to end-users and therefore, no modification on the end-user devices is necessary. This new system is featured with(1) a stronger audit scheme which is naturally coupled with the proposed architecture and does not suffer from the replay attack and(2) a transparent and efficient compensation mechanism for the fog-storage service providers. We provide rigorous theoretical analysis on the correctness and soundness of the proposed system. To the best of our knowledge, this is the first paper to discuss about a storage data audit scheme for fog-assisted cloud storage as well as the compensation mechanism for the service providers of the fog-storage service providers. 展开更多
关键词 FOG COMPUTING cloud COMPUTING network storage data audit MERKLE hash tree integer FACTORIZATION PAYMENT TRANSPARENCY
Approximate Data Aggregation in Sensor Equipped IoT Networks
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作者 Ji Li Madhuri Siddula +3 位作者 Xiuzhen Cheng Wei Cheng Zhi Tian Yingshu Li 《清华大学学报自然科学版(英文版)》 EI CAS CSCD 2020年第1期44-55,共12页
As Internet-of-Things(IoT) networks provide efficient ways to transfer data, they are used widely in data sensing applications. These applications can further include wireless sensor networks. One of the critical prob... As Internet-of-Things(IoT) networks provide efficient ways to transfer data, they are used widely in data sensing applications. These applications can further include wireless sensor networks. One of the critical problems in sensor-equipped IoT networks is to design energy efficient data aggregation algorithms that address the issues of maximum value and distinct set query. In this paper, we propose an algorithm based on uniform sampling and Bernoulli sampling to address these issues. We have provided logical proofs to show that the proposed algorithms return accurate results with a given probability. Simulation results show that these algorithms have high performance compared with a simple distributed algorithm in terms of energy consumption. 展开更多
关键词 DATA AGGREGATION sampling Internet-of-Things(IoT) NETWORKS
Design and Optimization of VLC Enabled Data Center Network
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作者 Yudong Qin Deke Guo +1 位作者 Xu Lin Geyao Cheng 《清华大学学报自然科学版(英文版)》 EI CAS CSCD 2020年第1期81-92,共12页
Visible-Light Communication(VLC) has the potential to provide dense and fast connectivity at low cost. In this paper we propose SFNet, a novel VLC-enabled hybrid data center network that extends the design of wireless... Visible-Light Communication(VLC) has the potential to provide dense and fast connectivity at low cost. In this paper we propose SFNet, a novel VLC-enabled hybrid data center network that extends the design of wireless Data Center Networks(DCNs) into three further dimensions:(1) fully wireless at the inter-rack level;(2) no need for a centralized control mechanism on wireless links;and(3) no need for any infrastructure-level alterations to data centers. Previous proposals typically cannot realize these three rationales simultaneously. To achieve this vision,the proposed SFNet augments fat-tree by organizing all racks into a wireless small-world network via VLC links. The use of VLC links eliminates hierarchical switches and cables in the wireless network, and thus reduces hardware investment and maintenance costs. To fully exploit the benefits of the topology of SFNet, we further propose its topology design and optimization method, routing scheme, and online flow scheduling algorithm. Comprehensive experiments indicate that SFNet exhibits good topological properties and network performance. 展开更多
关键词 Data CENTER Network(DCN) VISIBLE Light Communication(VLC) TOPOLOGY design
Real-time intelligent big data processing:technology, platform, and applications
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作者 Tongya ZHENG Gang CHEN +3 位作者 Xinyu WANG Chun CHEN Xingen WANG Sihui LUO 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第8期98-109,共12页
Human beings keep exploring the physical space using information means. Only recently, with the rapid development of information technologies and the increasing accumulation of data, human beings can learn more about ... Human beings keep exploring the physical space using information means. Only recently, with the rapid development of information technologies and the increasing accumulation of data, human beings can learn more about the unknown world with data-driven methods. Given data timeliness, there is a growing awareness of the importance of real-time data. There are two categories of technologies accounting for data processing: batching big data and streaming processing, which have not been integrated well. Thus,we propose an innovative incremental processing technology named after Stream Cube to process both big data and stream data. Also, we implement a real-time intelligent data processing system, which is based on real-time acquisition, real-time processing, real-time analysis, and real-time decision-making. The real-time intelligent data processing technology system is equipped with a batching big data platform, data analysis tools, and machine learning models. Based on our applications and analysis, the real-time intelligent data processing system is a crucial solution to the problems of the national society and economy. 展开更多
关键词 BATCHING big DATA streaming PROCESSING TECHNOLOGY REAL-TIME DATA PROCESSING incremental computation INTELLIGENT DATA PROCESSING system
ROCO:Using a Solid State Drive Cache to Improve the Performance of a Host-Aware Shingled Magnetic Recording Drive
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作者 Wen-Guo Liu Ling-Fang Zeng +1 位作者 Dan Feng Kenneth B.Kent 《计算机科学技术学报:英文版》 SCIE EI CSCD 2019年第1期61-76,共16页
Shingled magnetic recording (SMR)can effectively increase the capacity of hard disk drives (HDDs).Hostaware SMR (HA-SMR)is expected to be more popular than other SMR models because of its backward compatibility and ne... Shingled magnetic recording (SMR)can effectively increase the capacity of hard disk drives (HDDs).Hostaware SMR (HA-SMR)is expected to be more popular than other SMR models because of its backward compatibility and new SMR-specific APIs.However,an HA-SMR drive often suffers performance degradation under write-intensive workloads because of frequent non-sequential writes buffered in the disk cache.The non-sequential writes mainly come from update writes,small random writes and out-of-order writes.In this paper,we propose a hybrid storage system called ROCO which aims to use a solid state drive (SSD)cache to improve the performance of an HA-SMR drive.ROCO reorders out-of-order writes belonging to the same zone and uses the SSD cache to absorb update writes and small random writes.We also design a data replacement algorithm called CREA for the SSD cache.CREA first conducts zone-oriented hot/cold data identification to identify cold-cached zones and hot-cached zones,and then evicts data blocks belonging to colder zones with higher priorities that can be sequentially written or written through host-side read-modify-write operations.It gives the lowest priority to data blocks belonging to the hottest-cached zone that have to be non-sequentially written.Experimental results show that ROCO can effectively reduce non-sequential writes to the HA-SMR drive and improve the performance of the HA-SMR drive. 展开更多
关键词 solid state reordering zone-oriented DRIVE (SSD)cache host-aware shingled magnetic recording (HA-SMR)drive zone-oriented block hot/cold DATA identification DATA replacement algorithm
Enhancing Interest Forwarding for Fast Recovery from Unanticipated Data Access Failure in NDN 预览
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作者 Xiaoyan Hu Xuhui Liu +2 位作者 Lixia Zhao Jian Gong Guang Cheng 《中国通信:英文版》 SCIE CSCD 2019年第7期120-130,共11页
We show that an aggregated Interest in Named Data Networking (NDN) may fail to retrieve desired data since the Interest previously sent upstream for the same content is judged as a duplicate one and then dropped by an... We show that an aggregated Interest in Named Data Networking (NDN) may fail to retrieve desired data since the Interest previously sent upstream for the same content is judged as a duplicate one and then dropped by an upstream node due to its multipath forwarding. Furthermore, we propose NDRUDAF, a NACK based mechanism that enhances the Interest forwarding and enables Detection and fast Recovery from such Unanticipated Data Access Failure. In the NDN enhanced with NDRUDAF, the router that aggregates the Interest detects such unanticipated data access failure based on a negative acknowledgement from the upstream node that judges the Interest as a duplicate one. Then the router retransmits the Interest as soon as possible on behalf of the requester whose Interest is aggregated to fast recover from the data access failure. We qualitatively and quantitatively analyze the performance of the NDN enhanced with our proposed NDRUDAF and compare it with that of the present NDN. Our experimental results validate that NDRUDAF improves the system performance in case of such unanticipated data access failure in terms of data access delay and network resource utilization efficiency at routers. 展开更多
关键词 named DATA networking INTEREST aggregation multipath FORWARDING DATA access FAILURE negative ACKNOWLEDGEMENT
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Feature Screening for Ultrahigh-dimensional Censored Data with Varying Coefficient Single-index Model
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作者 Yi LIU 《应用数学学报:英文版》 CSCD 2019年第4期845-861,共17页
In this paper, we study the sure independence screening of ultrahigh-dimensional censored data with varying coefficient single-index model. This general model framework covers a large number of commonly used survival ... In this paper, we study the sure independence screening of ultrahigh-dimensional censored data with varying coefficient single-index model. This general model framework covers a large number of commonly used survival models. The property that the proposed method is not derived for a specific model is appealing in ultrahigh dimensional regressions, as it is difficult to specify a correct model for ultrahigh dimensional predictors.Once the assuming data generating process does not meet the actual one, the screening method based on the model will be problematic. We establish the sure screening property and consistency in ranking property of the proposed method. Simulations are conducted to study the finite sample performances, and the results demonstrate that the proposed method is competitive compared with the existing methods. We also illustrate the results via the analysis of data from The National Alzheimers Coordinating Center(NACC). 展开更多
关键词 censored data consistency in ranking PROPERTY FEATURE selection HIGH-DIMENSIONAL data sure SCREENING PROPERTY VARYING COEFFICIENT single-index model
An Energy-Efficient Data Collection Scheme Using Denoising Autoencoder in Wireless Sensor Networks
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作者 Guorui li Sancheng Peng +2 位作者 Cong Wang Jianwei Niu Ying Yuan 《清华大学学报自然科学版(英文版)》 EI CAS CSCD 2019年第1期86-96,共11页
As one of the key operations in Wireless Sensor Networks(WSNs), the energy-efficient data collection schemes have been actively explored in the literature. However, the transform basis for sparsifing the sensed data i... As one of the key operations in Wireless Sensor Networks(WSNs), the energy-efficient data collection schemes have been actively explored in the literature. However, the transform basis for sparsifing the sensed data is usually chosen empirically, and the transformed results are not always the sparsest. In this paper, we propose a Data Collection scheme based on Denoising Autoencoder(DCDA) to solve the above problem. In the data training phase, a Denoising AutoEncoder(DAE) is trained to compute the data measurement matrix and the data reconstruction matrix using the historical sensed data. Then, in the data collection phase, the sensed data of whole network are collected along a data collection tree. The data measurement matrix is utilized to compress the sensed data in each sensor node, and the data reconstruction matrix is utilized to reconstruct the original data in the sink.Finally, the data communication performance and data reconstruction performance of the proposed scheme are evaluated and compared with those of existing schemes using real-world sensed data. The experimental results show that compared to its counterparts, the proposed scheme results in a higher data compression rate, lower energy consumption, more accurate data reconstruction, and faster data reconstruction speed. 展开更多
关键词 wireless sensor NETWORKS DATA COLLECTION NEURAL NETWORKS autoencoder DATA reconstruction
Role of Trust, Privacy Concerns and Data Governance in Managers’ Decision on Adoption of Big Data Systems 预览
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作者 Selen Balkaya 《管理研究:英文版》 2019年第3期229-237,共9页
This paper investigates the role of trust, privacy concerns, and data governance on managers’ intention to use big data systems. In literature, trusting beliefs, such as functionality, helpfulness, and reliability we... This paper investigates the role of trust, privacy concerns, and data governance on managers’ intention to use big data systems. In literature, trusting beliefs, such as functionality, helpfulness, and reliability were found to be antecedent of trust in technological artifacts. Notice, access, choice, and security principles were found to be crucial in eliminating privacy concerns. On the other hand, this paper focuses on data storage and data collection which have been significant criterion for managers in evaluating companies’ data governance policies. A model depicting the relationships amongst all these factors and their relation to users’ intention to adopt big data systems and a scale was proposed in the paper. 展开更多
关键词 big DATA SYSTEMS privacy CONCERNS DATA GOVERNANCE TRUST technology acceptance Introduction
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Quality control of marine big data——a case study of real-time observation station data in Qingdao 预览
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作者 QIAN Chengcheng LIU Aichao +4 位作者 HUANG Rui LIU Qingrong XU Wenkun ZHONG Shan YU Le 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2019年第6期1983-1993,共11页
Offshore waters provide resources for human beings,while on the other hand,threaten them because of marine disasters.Ocean stations are part of offshore observation networks,and the quality of their data is of great s... Offshore waters provide resources for human beings,while on the other hand,threaten them because of marine disasters.Ocean stations are part of offshore observation networks,and the quality of their data is of great significance for exploiting and protecting the ocean.We used hourly mean wave height,temperature,and pressure real-time observation data taken in the Xiaomaidao station(in Qingdao,China)from June 1,2017,to May 31,2018,to explore the data quality using eight quality control methods,and to discriminate the most effective method for Xiaomaidao station.After using the eight quality control methods,the percentages of the mean wave height,temperature,and pressure data that passed the tests were 89.6%,88.3%,and 98.6%,respectively.With the marine disaster(wave alarm report)data,the values failed in the test mainly due to the influence of aging observation equipment and missing data transmissions.The mean wave height is often affected by dynamic marine disasters,so the continuity test method is not effective.The correlation test with other related parameters would be more useful for the mean wave height. 展开更多
关键词 quality control REAL-TIME STATION DATA MARINE BIG DATA Xiaomaidao STATION MARINE DISASTER
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Thoughts on the development of "data News" in the era of big data 预览
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作者 Shen Zhengbo Yuan Shaozhi 《探索-媒体与传播研究》 2019年第1期28-30,共3页
With"Robot Writing""Drone"And"Google Glasses"It is widely used in news reports. The trend of news report defocusing and defocusing is becoming more and more obvious,"Data news"H... With"Robot Writing""Drone"And"Google Glasses"It is widely used in news reports. The trend of news report defocusing and defocusing is becoming more and more obvious,"Data news"However, due to the current network environment, the professionalism of Data news has been questioned. Starting from the phenomenon, this paper discusses the problems existing in the development of data news. 展开更多
关键词 BIG DATA DATA NEWS NORMALIZATION OBJECTIVITY
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数据服务跨境贸易及调整规则研究 预览
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作者 李海英 《图书与情报》 CSSCI 北大核心 2019年第2期11-15,共5页
随着数字化技术进展与跨境数据传输总量激增,国际性数据服务已经成为全球重要议题,进而构成整个数字经济的基础。亟待探讨关注个人数据保护和数据跨境流动的调整规则,聚焦其对数字产品的影响,支撑我国数据跨境贸易的长足发展,争取相关... 随着数字化技术进展与跨境数据传输总量激增,国际性数据服务已经成为全球重要议题,进而构成整个数字经济的基础。亟待探讨关注个人数据保护和数据跨境流动的调整规则,聚焦其对数字产品的影响,支撑我国数据跨境贸易的长足发展,争取相关国际规则制定与实施的话语权。 展开更多
关键词 数据 跨境数字贸易 数据服务 国际规则
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Moving Objects with Transportation Modes:A Survey
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作者 Jian-Qiu Xu Ralf Hartmut Güting +1 位作者 Yu Zheng Ouri Wolfson 《计算机科学技术学报:英文版》 SCIE EI CSCD 2019年第4期709-726,共18页
In this article,we survey the main achievements of moving objects with transportation modes that span the past decade.As an important kind of human behavior,transportation modes reflect characteristic movement feature... In this article,we survey the main achievements of moving objects with transportation modes that span the past decade.As an important kind of human behavior,transportation modes reflect characteristic movement features and enrich the mobility with informative knowledge.We make explicit comparisons with closely related work that investigates moving objects by incorporating into location-dependent semantics and descriptive attributes.An exhaustive survey is offered by considering the following aspects:1)modeling and representing mobility data with motion modes;2)answering spatio-temporal queries with transportation modes;3)query optimization techniques;4)predicting transportation modes from sensor data,e.g.,GPS-enabled devices.Several new and emergent issues concerning transportation modes are proposed for future research. 展开更多
关键词 MOVING OBJECT TRANSPORTATION mode DATA model performance DATA GENERATOR
Research on the Big Data Cloud Computing Based on the Network Data Mining 预览
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作者 ZHANG Haiyang ZHANG Zhiwei 《国际英语教育研究:英文版》 2019年第2期72-74,共3页
The big data cloud computing is a new computing mode,which integrates the distributed processing,the parallel processing,the network computing,the virtualization technology,the load balancing and other network technol... The big data cloud computing is a new computing mode,which integrates the distributed processing,the parallel processing,the network computing,the virtualization technology,the load balancing and other network technologies.Under the operation of the big data cloud computing system,the computing resources can be distributed in a resource pool composed of a large number of the computers,allowing users to connect with the remote computer systems according to their own data information needs. 展开更多
关键词 NETWORK DATA mining BIG DATA cloud COMPUTING technology processing
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Research on the Data Mining Technology in College Students'Attendance System Based on the Big Data Architecture 预览
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作者 ZHONG Jian 《国际英语教育研究:英文版》 2019年第2期85-87,共3页
With the development and improvement of the information technologies,the increasing of the upper application systems and the rapid expansion of the data accumulated in the campus information environment,a typical camp... With the development and improvement of the information technologies,the increasing of the upper application systems and the rapid expansion of the data accumulated in the campus information environment,a typical campus big data environment has initially been formed.Because of the characteristics of the higher education,students'mobility is great and their learning environment is uncertain,so that the students'attendance mostly used the manual naming.The student attendance system based on the big data architecture is relying on the campus network,and adopting the appropriate sensors.Through the data mining technology,combined with the campus One Card solution,we can realize the management of the attendance without naming in class.It can not only strengthen the management of the students,but can also improve the management levels of the colleges and universities. 展开更多
关键词 BIG DATA ARCHITECTURE SYSTEM college students ATTENDANCE SYSTEM DATA mining technology
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个人数据保护在我国行政法治视域下的挑战与应对 预览
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作者 刘学涛 《北京邮电大学学报:社会科学版》 2019年第2期9-16,共8页
在大数据时代,保护个人数据安全是一项系统复杂的艰巨任务。在行政法治领域,由于企业过分强调对利益的追逐,公民权利保护意识不足及相关行政法律法规的缺失,使个人数据极易遭致侵害,进而导致权益遭受损失。据统计,我国数据资源80%以上... 在大数据时代,保护个人数据安全是一项系统复杂的艰巨任务。在行政法治领域,由于企业过分强调对利益的追逐,公民权利保护意识不足及相关行政法律法规的缺失,使个人数据极易遭致侵害,进而导致权益遭受损失。据统计,我国数据资源80%以上掌握在各级政府部门手里。鉴于数据时代个人数据发展快捷、迅速的特殊性,使数据保护迫在眉睫,下一步应该继续完善我国个人数据保护方面的行政法律法规,利用行政法的方式与措施来积极应对数据时代带来的巨大挑战。 展开更多
关键词 数据 泄露 个人数据保护 行政法治
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Task-Aware Flow Scheduling with Heterogeneous Utility Characteristics for Data Center Networks
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作者 Fang Dong Xiaolin Guo +1 位作者 Pengcheng Zhou Dian Shen 《清华大学学报自然科学版(英文版)》 EI CAS CSCD 2019年第4期400-411,共12页
With the continuous enrichment of cloud services, an increasing number of applications are being deployed in data centers. These emerging applications are often communication-intensive and data-parallel, and their per... With the continuous enrichment of cloud services, an increasing number of applications are being deployed in data centers. These emerging applications are often communication-intensive and data-parallel, and their performance is closely related to the underlying network. With their distributed nature, the applications consist of tasks that involve a collection of parallel flows. Traditional techniques to optimize flow-level metrics are agnostic to task-level requirements, leading to poor application-level performance. In this paper, we address the heterogeneous task-level requirements of applications and propose task-aware flow scheduling. First, we model tasks’ sensitivity to their completion time by utilities. Second, on the basis of Nash bargaining theory, we establish a flow scheduling model with heterogeneous utility characteristics, and analyze it using Lagrange multiplier method and KKT condition. Third, we propose two utility-aware bandwidth allocation algorithms with different practical constraints. Finally, we present Tasch, a system that enables tasks to maintain high utilities and guarantees the fairness of utilities. To demonstrate the feasibility of our system, we conduct comprehensive evaluations with realworld traffic trace. Communication stages complete up to 1.4 faster on average, task utilities increase up to 2.26,and the fairness of tasks improves up to 8.66 using Tasch in comparison to per-flow mechanisms. 展开更多
关键词 data CENTER networks coflow FLOW SCHEDULING DATA-INTENSIVE applications
PECS: Towards Personalized Edge Caching for Future Service-Centric Networks 预览
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作者 Ming Yan Wenwen Li +3 位作者 Chien Aun Chan Sen Bian Chih-Lin I André F. Gygax 《中国通信:英文版》 SCIE CSCD 2019年第8期93-106,共14页
Mobile operators face the challenge of how to best design a service-centric network that can effectively process the rapidly increasing number of bandwidth-intensive user requests while providing a higher quality of e... Mobile operators face the challenge of how to best design a service-centric network that can effectively process the rapidly increasing number of bandwidth-intensive user requests while providing a higher quality of experience(QoE). Existing content distribution networks(CDN) and mobile content distribution networks(mCDN) have both latency and throughput limitations due to being multiple network hops away from end-users. Here, we first propose a new Personalized Edge Caching System(PECS) architecture that employs big data analytics and mobile edge caching to provide personalized service access at the edge of the mobile network. Based on the proposed system architecture, the edge caching strategy based on user behavior and trajectory is analyzed. Employing our proposed PECS strategies, we use data mining algorithms to analyze the personalized trajectory and service usage patterns. Our findings provide guidance on how key technologies of PECS can be employed for current and future networks. Finally, we highlight the challenges associated with realizing such a system in 5G and beyond. 展开更多
关键词 BIG DATA DATA mining EDGE CACHING content network PERSONALIZED EDGE CACHING
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Big Data, Transparent World and Individual Freedom 预览
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作者 Huang Xinrong Yi Xin 《当代社会科学(英文)》 2019年第2期33-42,共10页
Big data technology turns everything into computerized information, so everything has its own data footprint. These footprints come together to form a data world that maps everything. By mining the data world, everyth... Big data technology turns everything into computerized information, so everything has its own data footprint. These footprints come together to form a data world that maps everything. By mining the data world, everything can be calculated and recognized. Our black box world is gradually open and transparent. Everything can be recognized, grasped, and predicted. Although big data may diminish individual privacy and even threaten personal freedom, through the precise portrayal and analysis of big data, people will gradually come to understand the laws of nature and society, and those once hidden in the black box will gradually move from the realm of necessity to the realm of freedom. Big data, therefore, brings a new world of freedom while bringing constraints to individuals. 展开更多
关键词 BID DATA DATA world TRANSPARENT world INDIVIDUAL FREEDOM
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