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A Software-Defined Approach to IoT Networking

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ZTE Communications 2016年第1期14卷 61-66页

作者： Christian Jacquenet Mohamed Boucadair france telecom orange

It is foreseen that the Internet of Things (IoT) will comprise billions of connected devices, and this will make the provi?sioning and operation of some IoT connectivity services more challenging. Indeed, IoT services are very different from lega?cy Internet services because of their dimensioning figures and also because IoT services differ dramatically in terms of na?ture and constraints. For example, IoT services often rely on energy and CPU?constrained sensor technologies, regardless of whether the service is for home automation, smart building, e?health, or power or water metering on a regional or national scale. Also, some IoT services, such as dynamic monitoring of biometric data, manipulation of sensitive information, and pri?vacy needs to be safeguarded whenever this information is for?warded over the underlying IoT network infrastructure. This paper discusses how software?defined networking (SDN) can facilitate the deployment and operation of some advanced IoT services regardless of their nature or scope. SDN introduces a high degree of automation in service delivery and operation-from dynamic IoT service parameter exposure and negotiation to resource allocation, service fulfillment, and assurance. This paper does not argue that all IoT services must adopt SDN. Rather, it is left to the discretion of operators to decide which IoT services can best leverage SDN capabilities. This paper only discusses managed IoT services, i.e., services that are op?erated by a service provider.

关键词： automation dynamic service provisioning Internet of Things service function chaining software-defined networking

Testing protocols in Internet of Things by a formal passive technique

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Science China(Information Sciences) 2014年第3期57卷 6-18页

作者： Xiaoping CHE Stephane MAAG Insititut Mines-telecom/telecom SudParis CNRS UMR 5157Evry 91000France

In recent years,Extensible Messaging and Presence Protocol(XMPP)is gaining momentum in Internet of Things(IoT).It has been widely used in chatting,message exchanging and unique *** a matter of course,it raises an interesting issue:how to formally test the conformance and performance of XMPP in IoT *** conformance testing of communicating protocols is a functional test that verifies whether the behaviors of the protocol satisfy defined requirements,performance testing is a qualitative and quantitative test that aims at checking whether the performance requirements of the protocol are satisfied under certain *** this paper,we present a logic-based passive testing approach that can test both the conformance and the performance of XMPP protocol through real execution traces and formally specified *** evaluate and assess our methodology,we present a developed prototype and the experiments with a set of XMPP ***,the relevant verdicts and conclusions are provided.

关键词： Internet of Things passive testing formal methods XMPP

COVAD: Content-oriented video anomaly detection using a self attention-based deep learning model

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Virtual Reality & Intelligent Hardware 2023年第1期5卷 24-41页

作者： Wenhao SHAO Praboda RAJAPAKSHA Yanyan WEI Dun LI Noel CRESPI Zhigang LUO College of Computer National University of Defense TechnologyChangsha 410073China telecom SudParis IMTInstitut Polytechnique de ParisPalaiseau 91764France Zhengzhou College of Finance and Economics Zhengzhou 450000China

Background Video anomaly detection has always been a hot topic and has attracted increasing *** of the existing methods for video anomaly detection depend on processing the entire video rather than considering only the significant context. Method This paper proposes a novel video anomaly detection method called COVAD that mainly focuses on the region of interest in the video instead of the entire video. Our proposed COVAD method is based on an autoencoded convolutional neural network and a coordinated attention mechanism,which can effectively capture meaningful objects in the video and dependencies among different objects. Relying on the existing memory-guided video frame prediction network, our algorithm can significantly predict the future motion and appearance of objects in a video more effectively. Result The proposed algorithm obtained better experimental results on multiple datasets and outperformed the baseline models considered in our analysis. Simultaneously, we provide an improved visual test that can provide pixel-level anomaly explanations.

关键词： Video surveillance Video anomaly detection Machine learning Deep learning Neural network Coordinate attention

Quaternion Diffusion for Color Image Filtering

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Journal of Computer Science & Technology 2006年第1期21卷 126-136,F0003页

作者：刘忠轩廉士国任真 france telecom R&D Beijing Beijing 100080 P.R. China

How to combine color and multiscale information is a fundamental question for computer vision, and quite a few color diffusion techniques have been presented. Most of these proposed techniques do not consider the direct interactions between color channel pairs. In this paper, a new method of color diffusion considering these effects is presented, which is based on quaternion diffusion （QD） equation. In addition to showing the solution to linear QD and its analysis, one form of nonlinear QD is discussed. Compared with other color diffusion techniques, considering the interactions between channel pairs, QD has the following advantages： 1） staircasing effect is avoided; 2） as diffusion tensor, the image derivative is regularized without requiring additional convolution; 3） less time is needed. Experimental results demonstrate the effectiveness of linear and nonlinear QD applied to natural color images for denoising by both visual and quantitative evaluations.

关键词： color image processing nonlinear filtering quaternion diffusion quaternion partial differential equation

A transcriptional cascade mediated by two APETALA2 family members orchestrates carotenoid biosynthesis in tomato

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Journal of Integrative Plant Biology 2024年第6期66卷 1227-1241页

作者： Xiaoqing He Kaidong Liu Yi Wu Weijie Xu Ruochen Wang Julien Pirrello Mondher Bouzayen Mengbo Wu Mingchun Liu Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education College of Life SciencesSichuan UniversityChengdu 610065China Life Science and Technology School Lingnan Normal UniversityZhanjiang 524048China Laboratoire de Recherche en Sciences Vegetales—Genomique et Biotechnologie des Fruits—UMR5546 Universite de ToulouseCNRSUPSToulouse-INPToulouse 31013France

Carotenoids are important nutrients for human health that must be obtained from plants since they cannot be biosynthesized by the human *** the regulatory mechanism of carotenoid metabolism in plants represents the first step toward manipulating carotenoid contents in plants by molecular design *** this study,we determined that SlAP2c,an APETALA2(AP2)family member,acts as a transcriptional repressor to regulate carotenoid biosynthesis in tomato(Solanum lycopersicum).Knockout of SlAP2c in both the“Micro Tom”and“Ailsa Craig”backgrounds resulted in greater lycopene accumulation,whereas overexpression of this gene led to orange-ripe fruit with significantly lower lycopene contents than the wild *** established that SlAP2c represses the expression of genes involved in lycopene biosynthesis by directly binding to the cis-elements in their ***,SlAP2c relies on its EAR motif to recruit the co-repressors TOPLESS(TPL)2/4 and forms a complex with histone deacetylase(had)1/3,thereby reducing the histone acetylation levels of lycopene biosynthesis ***,SlAP2a,a homolog of SlAP2c,acts upstream of SlAP2c and alleviates the SlAP2c-induced repression of lycopene biosynthesis genes by inhibiting SlAP2c transcription during fruit ***,we identified a transcriptional cascade mediated by AP2 family members that regulates lycopene biosynthesis during fruit ripening in tomato,laying the foundation for the manipulation of carotenoid metabolism in plants.

关键词： APETALA2 family members carotenoid biosynthesis tomato transcriptional cascade

Prediction of urban human mobility using large-scale taxi traces and its applications

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Frontiers of Computer Science 2012年第1期6卷 111-121页

作者： Xiaolong LI Gang PAN Zhaohui WU Guande QI Shijian LI Daqing ZHANG Wangsheng ZHANG Zonghui WANG Department of Computer Science Zhejiang UniversityHangzhou 310027China Institut telecom SudParis 91011 Evry CedexFrance

This paper investigates human mobility patterns in an urban taxi transportation system. This work focuses on predicting human mobility from discovering patterns of in the number of passenger pick-ups quantity （PUQ） from urban hotspots. This paper proposes an improved ARIMA based prediction method to forecast the spatial-temporal variation of passengers in a hotspot. Evaluation with a large-scale real- world data set of 4 000 taxis＇ GPS traces over one year shows a prediction error of only 5.8%. We also explore the applica- tion of the pl^di^fioti approach to help drivers find their next passetlgerS, The sinatllation results using historical real-world data demonstrate that, with our guidance, drivers can reduce the time taken and distance travelled, to find their next pas- senger＋ by 37.1% and 6.4% respectively,

关键词： urban traffic GPS traces hotspots human mo-bility prediction auto-regressive integrated moving average(ARiMA)

A review of stabilization methods for DCMG with CPL,the role of bandwidth limits and droop control

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Protection and Control of Modern Power Systems 2022年第1期7卷 14-25页

作者： Sarah Ansari Jing Zhang Rajat Emanuel Singh Engineering and Information Technology University of ArkansasLittle RockLittle RockUSA. Northwestern College Orange CityIowaUSA.

DC microgrids(DCMGs)integrate and coordinate various DC distribution generation units including various renew-able energy sources and battery storage systems,and have been used in satellites,the International Space Station,telecom power stations,computer power supplies,electric aircraft,and electric ***,the presence of constant power loads(CPLs)can cause instability in ***,this paper reviews the stabilization techniques that can resolve instability caused by CPLs,as well as various parameters of CPLs,such as bandwidth,and the frequency of the CPLs that can stabilize the *** also discusses recent trends and future work in finding stability limits using the parameters of *** should be useful for directing research towards appropriate mathematical and experimental approaches for the stability of DCMGs with CPLs.

关键词： DC microgrids DC distribution generation units Stability Constant power loads Bandwidth

SYSTEMATIC DESIGN OF SINGLE CARRIER OVERLAP FREQUENCY DOMAIN EQUALIZATION

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Journal of Systems Science & Complexity 2010年第1期23卷 50-60页

作者： Wladimir BOCQUET Kazunori HAYASHI Hideaki SAKAI Oranqe Labs Tokyo France Telecom Japan Co.Ltd Department of Systems Science Graduate School of InformaticsKyoto University

This paper proposes a systematic design method of overlap frequency domain equalization(FDE) for single carrier (SC) transmission without a guard interval (GI).Based on the analysis of signal-to-interference-plus-noise ratio (SINR) of the equalizer output for each symbol,the authors adaptivelydetermine the block of the overlap FDE,where the block is defined as a set of symbols at the equalizeroutput with sufficiently low error rate,for a certain fixed sliding window size,which corresponds toa fast Fourier transform (FFT) window *** proposed method takes advantage of the fact thatthe utility part of the equalized signal is localized around the center of the FFT *** addition,the authors also propose to adjust the block size in order to control the computational complexity ofthe equalization per processed sample associating with the average bit error rate (BER) of the *** results show that the proposed scheme can achieve comparable BER performance to theconventional SC-FDE scheme with sufficient GI insertion for both the coded and uncoded cases withvarious modulation levels,while requiring lower computational complexity compared to the SC overlapFDE transmission with the fixed block.

关键词：单载波频域均衡系统化计算复杂性快速傅立叶变换计重滑动窗口平均误码率误码率性能

Rate-distortion optimized bitstream switching for peer-to-peer live streaming

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第4期9卷 445-456页

作者： Jin-feng ZHANG Rong-gang WANG Jian-wei NIU Yuan DONG Hai-la WANG School of Computer Science and Technology Beijing University of Aeronautics and Astronautics Beijing 100083 China france telecom R＆D Beijing Beijing 100080 China

Peer-to-peer (P2P) technology provides a cost-effective and scalable way to distribute video data. However, high heterogeneity of the P2P network, which rises not only from heterogeneous link capacity between peers but also from dynamic variation of available bandwidth, brings forward great challenge to video streaming. To attack this problem, an adaptive scheme based on rate-distortion optimization (RDO) is proposed in this paper. While low complexity RDO based frame dropping is exploited to shape bitrate into available bandwidth in peers, the streamed bitstream is dynamically switched among multiple available versions in an RDO way by the streaming server. Simulation results show that the proposed scheme based on RDO achieves great gain in overall perceived quality over simple heuristic schemes.

关键词：图像通信开关电子技术优化设计