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未来有线电视网络演进之展望

未来有线电视网络演进之展望

Impact of the spindle number on the material transport and mixing during planetary roller melt granulation Author links open overlay panel

2014国际传输与覆盖研讨会

作者：周强 tom cloonan John Ulm ARRIS公司

有线电视的未来的发展充满着许多变数,本文将从著名的尼尔森定律出发,设立了一个比较合适的流量工程模型。根据该模型,分析了有线电视网络的未来发展趋势以及所面临的挑战。本文特别针对一个典型的国内有线电视运营商的实际情况进行分析... 详细信息

有线电视的未来的发展充满着许多变数,本文将从著名的尼尔森定律出发,设立了一个比较合适的流量工程模型。根据该模型,分析了有线电视网络的未来发展趋势以及所面临的挑战。本文特别针对一个典型的国内有线电视运营商的实际情况进行分析,对其网络的未来演进的方向和规划提出相应的建议。

关键词：有线电视网络流量工程模型尼尔森定律理论运行机制

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Particuology 2024年第8期91卷 260-267页

作者： tom Lang Jens Bartsch Laboratory of Solids Process Engineering Department of Biochemical and Chemical EngineeringTU Dortmund University44227DortmundGermany

In comparison to the established twin-screw machines,the application of a planetary roller granulator for continuous operation of melt granulation is a promising alternative based on the unique process *** initial study focused on the material transport during processing as a key driver for the overall ***,the impact of direct process parameters on the residence time distribution was the main *** investigations are complemented in this study by considering the free processing volume,which is defined by the number of planetary spindles applied within a *** impact on the processing conditions is evaluated with respect to the process setting in terms of feed rate and rotation *** results highlight the potential of altering the underlying transport function in planetary roller melt granulation(PRMG)via the investigated direct process and equipment *** impact of the feed rate is lower in comparison,while a higher rotation speed as well as a higher free processing volume promote material ***,a normalization of the determined residence time distribution(RTD)model data was feasible with respect to the process settings and the number of applied planetary spindles in the processing *** demonstrates the key role of the free processing volume in the fundamental mechanisms of material transport and mixing during PRMG.

关键词： Continuous manufacturing Melt granulation Planetaryroller granulator Quality-by-Design Residence time Material mixing

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使现有HFC网络价值最大化—中国视点

使现有HFC网络价值最大化—中国视点

2008国际传输与覆盖研讨会

作者： tom cloonan Stan Brovont Ed Lotts Arris公司 Arris公司集团市场与业务拓展部 Arris公司业务拓展部

中国宽带网络运营商使用各种不同的系统为最终用户提供服务,包括传统的DSL设备、标准的HFC系统以及光纤到户设备等。有些运营商选择了无源光纤网（PON）而放弃了正在发展的HFC。随着技术标准和开放接口的不断开发并被引入到有线电视领域... 详细信息

中国宽带网络运营商使用各种不同的系统为最终用户提供服务,包括传统的DSL设备、标准的HFC系统以及光纤到户设备等。有些运营商选择了无源光纤网（PON）而放弃了正在发展的HFC。随着技术标准和开放接口的不断开发并被引入到有线电视领域,HFC网络开展服务的面貌发生了巨大的变化。本文拟从技术和业务角度分析PON和HFC的差异,包括在满足用户未来需求方面的差异,并以侧重分析HFC的未来作为本文的结语。网络运营商越来越多地围绕"三重业务"的概念提供视频、话音和数据服务。近期在监管方面发生的变化已经允许信产部属下的实体开展视频服务,同时允许国家广电总局管理的实体开展数据和话音服务。国家广电总局力推在2015年向数字化全面转换,这使得所有的服务提供商在今后的时间里将逐渐变化和演进。伴随着这些实体所使用网络的不断发展,这些变化和演进将会为他们带来比现在的业务更高的投资回报率。DOCSIS、时移视频和视频点播曾经被设想为HFC网络运营商的新颖服务。新颖服务不仅能够带来经济效益,而且可以利用当前的HFC网络基础设施大规模部署。通过DOCSIS等技术标准的完善和普及,新颖服务的设想已经实现。DOCSIS等技术标准顺应了HFC网络运营商所期待的业务发展趋势。这种全球性的趋势显示了市场在向扩大规模、增加服务品种以及降低资金成本和运营成本的方向转变。本文将分析新技术在三重业务领域中的应用给当前和未来服务造成的影响,侧重分析中国的市场及其需求。其中有关在全球开展着的服务的讨论以及如何在中国实施可能是大家感兴趣的话题。这些服务包括视频点播、网络个人视频录像机（PVR）、高速数据传输、IP话音（VoIP）和IPTV。美国互联网发展的历史以及对它的预测可以用来与中国市场进行比较,并以此推想中国网络运营商未来面对的总体带宽需求。本文还将讨论DOCSIS 3.O所能提供的未来服务。该标准具有扩展性和成本效益特性,能够使每个用户享受160 Mbps或更高的数据传输速率,享受更丰富的游戏体验,享受基于互联网的视频服务,提供企业或商业服务,并有可能将核心视频从MPEG传输流转换为IⅢ。此外,本文还将简洁地讨论一下DOCSIS 3.0的一些其他功能,包括信道绑定、IP组播、IPv6、安全性、物理层、MAC层及其管理等。

关键词： HFC网络价值最大化网络服务网络运营商

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对有线电视网络架构的思考

世界宽带网络 2009年第12期16卷 72-73页

作者：肯·怀特 tom cloonan Stan Brovont Bill Dawson Ed Lotts ARRIS

一引言目前宽带网络运营商面临着越来越多的来自终端用户要求提供最新最快服务的需求。这些新的服务已经从简单的低带宽应用如VoIP，升级为需要更高带宽的服务如IP视频。有线运营商只有修改当前网络架构，才能保证提供这些最新的服务。... 详细信息

一引言目前宽带网络运营商面临着越来越多的来自终端用户要求提供最新最快服务的需求。这些新的服务已经从简单的低带宽应用如VoIP，升级为需要更高带宽的服务如IP视频。有线运营商只有修改当前网络架构，才能保证提供这些最新的服务。本文分析了HFC网络的演进，

关键词：网络架构有线电视网络运营商 HFC网络用户要求 VoIP IP视频高带宽

Liquid superlubricity of lubricants containing hydroxyl groups and their aqueous solution under rolling/sliding conditions

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Friction 2024年第1期12卷 164-173页

作者： tomáš POLÁČEK Petr ŠPERKA Ivan KŘUPKA Faculty of Mechanical Engineering Brno University of TechnologyBrno 61669Czech Republic

Macroscale rolling/sliding conditions are in the superlubricity,a little-studied topic so *** purpose of this paper is to examine the formation of elastohydrodynamic lubrication(EHL)films by water-based lubricants(glycerol and polyethylene glycol(PEG)),providing superlubricous *** were carried out on an optical ball-on-disc tribometer under rolling/sliding *** film thickness was measured by the thin film colorimetric interferometry,and the viscosity of liquids was measured by rotational and high-pressure falling body *** results show that tribochemical reactions are not the mandatory reason for friction to reach the superlubricity level when using the water-based *** studied liquids themselves are almost *** the addition of water,the signs of shear thinning behavior disappear even *** conditions for this type of lubricant can be predicted using the known Hamrock–Dowson *** anomaly in the thickness of the lubricants was observed as an abrupt change at certain *** more PEG there is in the lubricant,the higher the thickness at the beginning of the jump.

关键词： macroscale superlubricity super low traction water-based lubricants elastohydrodynamic lubrication(EHL) film thickness

Accelerating snail vector genomics

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贫困所致传染病(英文) 2024年第3期13卷 6-10页

作者： Pennance tom Rollinson David College of Osteopathic Medicine of the Pacific – Northwest Western University of Health Sciences Lebanon OR USA Global Schistosomiasis Alliance Ealing Cross Uxbridge Road Ealing London W5BW UK Science Department Natural History Museum Cromwell Road London SW5BD UK

The three most important genera of snails for the transmission of schistosomes areBulinus,Biomphalaria andOncomelania. Each of these genera, found in two distantly related families, includes species that act as the intermediate host for one of the three most widespread schistosome species infecting humans,Schistosoma haematobium, S. mansoni andS. japonicum, respectively. An important step in the fight against schistosomiasis in Asia has been taken with the publication of the article "Chromosome-level genome assembly ofOncomelania hupensis: the intermediate snail host ofSchistosoma japonicum", which means that genomes for all three major genera, including species across three continents, are now available in the public domain. This includes the first genomes of African snail vectors, namelyBiomphalaria sudanica,Bi. pfeifferi andBulinus truncatus, as well as high-quality chromosome level assemblies for South AmericanBi. glabrata. Most importantly, the wealth of new genomic and transcriptomic data is helping to establish the specific molecular mechanisms that underly compatibility between snails and their schistosomes, which although diverse and complex, may help to identify potential targets dictating host parasite interactions that can be utilised in future transmission control strategies. This new work onOncomelania hupensis and indeed studies on other snail vectors, which provide deep insights into the genome, will stimulate research that may well lead to new and much needed control interventions.

关键词： Oncomelania Bulinus Biomphalaria Snail vectors Genomics

Predicting the coefficient of friction in a sliding contact by applying machine learning to acoustic emission data

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Friction 2024年第6期12卷 1299-1321页

作者： Robert GUTIERREZ Tianshi FANG Robert MAINWARING tom REDDYHOFF Tribology Group Department of Mechanical EngineeringImperial College LondonExhibition RoadLondon SW72AZUK Shell Global Solutions(US)Inc.Shell Technology Center Houston 3333 Highway 6 SouthHoustonTX 77082USA Shell International Petroleum Company Limited Shell CentreYork RoadLondon SE17NAUK

It is increasingly important to monitor sliding interfaces within machines,since this is where both energy is lost,and failures *** emission(AE)techniques offer a way to monitor contacts remotely without requiring transparent or electrically conductive ***,acoustic data from sliding contacts is notoriously complex and difficult to ***,we simultaneously measure coefficient of friction(with a conventional force transducer)and acoustic emission(with a piezoelectric sensor and high acquisition rate digitizer)produced by a steel‒steel rubbing *** data is then used to train machine learning(ML)algorithms(e.g.,Gaussian process regression(GPR)and support vector machine(SVM))to correlated acoustic emission with *** training requires the dense AE data to first be reduced in size and a range of processing techniques are assessed for this(e.g.,down-sampling,averaging,fast Fourier transforms(FFTs),histograms).Next,fresh,unseen AE data is given to the trained model and the resulting friction predictions are compared with the directly measured *** is excellent agreement between the measured and predicted friction when the GPR model is used on AE histogram data,with root mean square(RMS)errors as low as 0.03 and Pearson correlation coefficients reaching ***,predictions remain accurate despite changes in test conditions such as normal load,reciprocating frequency,and stroke *** paves the way for remote,acoustic measurements of friction in inaccessible locations within machinery to increase mechanical efficiency and avoid costly failure/needless maintenance.

关键词： acoustic emission condition monitoring friction machine learning Gaussian process regression support vector machine

Granger causal representation learning for groups of time series

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Science China(Information Sciences) 2024年第5期67卷 56-68页

作者： Ruichu CAI Yunjin WU Xiaokai HUANG Wei CHEN tom Z.J.FU Zhifeng HAO School of Computer Science Guangdong University of Technology Peng Cheng Laboratory College of Science Shantou University

Discovering causality from multivariate time series is an important but challenging *** existing methods focus on estimating the Granger causal structures among multivariate time series,while ignoring the prior knowledge of these time series, e.g., the group of the time series. Focusing on discovering the Granger causal structures among groups of time series, we propose a Granger causal representation learning method to solve this problem. First, we use the multiset canonical correlation analysis method to learn the Granger causal representation of each group of time series. Then, we model the Granger causal relationships among the learned Granger causal representations using a recurrent neural network with temporal information. Finally, we formulate the above two stages into one unified optimization problem, which is efficiently solved using the augmented Lagrangian method. We conduct extensive experiments on synthetic and real-world datasets to validate the correctness and effectiveness of the proposed method.

关键词： Granger causal discovery Granger causal representation learning time series data recurrent neural network multiset canonical correlation analysis

An integrated microfluidic platform for nucleic acid testing

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Microsystems & Nanoengineering 2024年第3期10卷 181-194页

作者： Antao Sun Petra Vopařilová Xiaocheng Liu Bingqian Kou tomášŘezníček tomášLednický Sheng Ni JiříKudr Ondřej Zítka Zdenka Fohlerová Petr Pajer Haoqing Zhang Pavel Neužil Ministry of Education Key Laboratory of Micro and Nano Systems for Aerospace School of Mechanical EngineeringNorthwestern Polytechnical University127 West Youyi RoadXi’anShaanxi 710072P.R.China Department of Chemistry and Biochemistry Mendel University in BrnoZemědělská161300 BrnoCzech Republic ITD Tech s.r.o Osvoboditelů100573581 BohumínCzech Republic Central European Institute of Technology Brno University of TechnologyPurkyňova 123Brno 61200Czech Republic Department of Electronic and Computer Engineering The Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong SARChina Department of Microelectronics Faculty of Electrical Engineering and CommunicationBrno University of TechnologyTechnická3058/10Brno 61600Czech Republic Military Health Institute U Vojenskénemocnice 120016200 Praha 6Czech Republic The Key Laboratory of Biomedical Information Engineering of Ministry of Education School of Life Science and TechnologyXi’an Jiaotong UniversityXi’anShaanxi 710049P.R.China Bioinspired Engineering and Biomechanics Center(BEBC) Xi’an Jiaotong UniversityXi’an 710049P.R.China

This study presents a rapid and versatile low-cost sample-to-answer system for SARS-CoV-2 *** system integrates the extraction and purification of nucleic acids,followed by amplification via either reverse transcriptionquantitative polymerase chain reaction(RT–qPCR)or reverse transcription loop-mediated isothermal amplification(RT–LAMP).By meeting diverse diagnostic and reagent needs,the platform yields testing results that closely align with those of commercial RT-LAMP and RT‒qPCR *** advantages of our system include its speed and *** assay is completed within 28 min,including sample loading(5 min),ribonucleic acid(RNA)extraction(3 min),and RT-LAMP(20 min).The cost of each assay is≈$9.5,and this pricing is competitive against that of Food and Drug Administration(FDA)-approved commercial *** some RNA loss during on-chip extraction is observed,the platform maintains a potential limit of detection lower than 297 *** makes the system particularly useful in environments where centralized laboratories are either unavailable or inconveniently *** key feature is the platform’s versatility,allowing users to choose between RT‒qPCR or RT‒LAMP tests based on specific requirements.

关键词： testing maintain versatile