Using Coordination Middleware for Location-Aware Computing A Lime Case Study
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化工进展Chemical Industry and Engineering Progress2024 年第 43 卷第 4 期具有烷基磺酸侧链的凝胶型聚苯并咪唑质子交换膜的制备与表征朱泰忠1,张良1,黄泽权1,罗伶萍1,黄菲1,薛立新1,2(1 浙江工业大学化工学院膜分离与水科学技术中心,浙江 杭州 310014;2温州大学化学与材料工程学院,浙江 温州 325035)摘要:磷酸(PA )掺杂聚苯并咪唑(PBI )以其优异的热化学稳定性和高玻璃化转变温度成为高温质子交换膜燃料电池(HT-PEMFCs )的首选材料。
然而,由于低温下磷酸较弱的解离度和传递速率,导致膜的质子传导性能不佳,电池冷启动困难。
因此,研发可在宽温湿度范围内高效运行的高温质子交换膜成为当前挑战。
特别是拓宽其低温运行窗口、实现冷启动对这类质子交换膜燃料电池在新能源汽车领域的实际应用具有重要意义。
本文通过多聚磷酸溶胶凝胶工艺与内酯开环反应设计并合成了一系列磷酸掺杂的具有柔性烷基磺酸侧链的凝胶型聚苯并咪唑质子交换膜。
重点探究了烷基磺酸的引入以及侧链长度对磷酸掺杂水平、不同温湿度下的质子传导率及稳定性的影响规律。
研究结果表明,所制备的质子交换膜具有凝胶型自组装片层堆叠的多孔结构,有利于吸收大量磷酸并提供质子快速传输通道。
其中,PA/PS-PBI 展现出了在宽温域范围内均优于目前所报道的其他工作的质子传导性能。
特别是常温下,其质子传导率从原膜的0.0286S/cm 提升至0.0694S/cm 。
80℃下,其质子传导率从原膜的0.1117S/cm 提升至0.1619S/cm 。
200℃下,其质子传导率从原膜的0.2609S/cm 提升至0.3578S/cm 。
此外,该膜在80℃和0%相对湿度(RH )条件下仍可具有与Nafion 膜在100%RH 时相当的质子传导率,为打破质子交换膜经典定义、实现宽温域(25~240℃)运行提供新的方案。
2022年 2月 图 学 学 报 February2022第43卷 第1期 JOURNAL OF GRAPHICS Vol.43No.1
收稿日期:2021-06-23;定稿日期:2021-08-06 Received:23 June,2021;Finalized:6 August,2021 基金项目:科技部重点研发计划项目(2020YFA0714100) Foundation items:Key R&D Program of the Ministry of Science and Technology (2020YFA0714100) 第一作者:唐晓天(1997–),男,硕士研究生。主要研究方向为视频超分辨率重建。E-mail:****************First author:TANG Xiao-tian (1997–), master student. His main research interest covers video super-resolution reconstruction. E-mail:****************通信作者:李 峰(1975–),男,研究员,博士。主要研究方向为图像重建、压缩感知等。E-mail:**************** Corresponding author:LI Feng (1975–), researcher, Ph.D. His main research interests cover image reconstruction, compressed sensing, etc. E-mail:****************
基于多尺度时域3D卷积的视频超分辨率重建 唐晓天1,2, 马 骏2, 李 峰1, 杨 雪1, 梁 亮3 (1. 钱学森空间技术实验室,北京 100086; 2. 河南大学软件学院,河南 开封 475004; 3. 清华大学电子工程系,北京 100084)
2022⁃07⁃10计算机应用,Journal of Computer Applications2022,42(7):2170-2176ISSN 1001⁃9081CODEN JYIIDU http ://基于点线特征融合的低纹理单目视觉同时定位与地图构建算法潘高峰,樊渊,汝玉,郭予超(安徽大学电气工程与自动化学院,合肥230601)(∗通信作者电子邮箱yuanf@ )摘要:当图像因相机快速运动造成模糊或者处在低纹理场景时,仅使用点特征的同步定位与地图构建(SLAM )算法难以跟踪提取足够多的特征点,导致定位精度和匹配鲁棒性较差。
而如果造成误匹配,甚至系统都无法工作。
针对上述问题,提出了一种基于点线特征融合的低纹理单目SLAM 算法。
首先,加入了线特征来加强系统稳定性,并解决了点特征算法在低纹理场景中提取不足的问题;然后,对点、线特征提取数量的选择引入了加权的思想,根据场景的丰富程度,对点线特征的权重进行了合理分配。
所提算法是在低纹理场景下运行的,因而设置以线特征为主、点特征为辅。
在TUM 室内数据集上的实验结果表明,与现有的点线特征算法相比,所提算法有效地提高了线特征的匹配精度,使得轨迹误差减小了大约9个百分点,也使得特征提取时间减少了30个百分点,使加入的线特征在低纹理场景中发挥出积极有效的作用,提高了数据整体的准确度和可信度。
关键词:单目视觉;点线融合;线匹配;低纹理场景;特征加权中图分类号:TP242.6文献标志码:ALow -texture monocular visual simultaneous localization andmapping algorithm based on point -line feature fusionPAN Gaofeng ,FAN Yuan ,RU Yu ,GUO Yuchao(School of Electrical Engineering and Automation ,Anhui University ,Hefei Anhui 230601,China )Abstract:When the image is blurred due to rapid camera movement or in low -texture scenes ,the SimultaneousLocalization And Mapping (SLAM )algorithm using only point features is difficult to track and extract enough feature points ,resulting in poor positioning accuracy and matching robustness.If it causes false matching ,even the system cannot work.To solve the problem ,a low -texture monocular SLAM algorithm based on point -line feature fusion was proposed.Firstly ,the line features were added to enhance the system stability ,and the problem of insufficient extraction of point feature algorithm in low texture scenes was solved.Then ,the idea of weighting was introduced for the extraction number selection of point andline features ,and the weight of point and line features were allocated reasonably according to the richness of the scene.The proposed algorithm ran in low -texture scenes ,so the line features were set as the main features and the point features were set as the auxiliary features.Experimental results on the TUM indoor dataset show that compared with the existing point -line feature algorithms ,the proposed algorithm can effectively improve the matching precision of the line features ,has the trajectory error reduced by about 9percentage points ,and has the feature extraction time reduced by 30percentage points.As the result ,the added line features play a positive and effective role in low -texture scenes ,and improve the overallaccuracy and reliability of the data.Key words:monocular vision;point -line fusion;line matching;low -texture scene;feature weighting0引言同时定位与地图构建(Simultaneous Localization AndMapping ,SLAM )是指机器人等主体上搭载特定传感器,在没有环境先验信息的情况下,在运动整体过程中建立环境信息的模型,同时估计自己的各种姿态运动[1]。
总第323期交 通 科 技SerialNo.323 2024第2期TransportationScience&TechnologyNo.2Apr.2024DOI10.3963/j.issn.1671 7570.2024.02.019收稿日期:2023 10 26第一作者:唐剑(1996-),男,硕士,助理工程师。
基于BIM的移动模架智能监测系统研究及应用唐 剑1,2 吴巨峰1,2 钟继卫1,2 刘宏刚1,2 尹森浩1,2(1.桥梁智能与绿色建造全国重点实验室 武汉 430034; 2.中铁桥研科技有限公司 武汉 430034)摘 要 针对环境因素、结构因素等致使移动模架在施工中发生安全事故的问题,结合结构有限元分析,研发集设备运行监测、环境监测、结构监测,以及BIM数字孪生于一体的移动模架智能监测预警系统,依托常泰长江大桥移动模架施工项目,对施工过程进行实时监测。
结果表明,移动模架支腿主梁应力过大、主梁变形过大,以及开合不同步等问题易使结构处于不安全状态,结合设备运行监测、结构监测、环境监测的的移动模架智能监测系统能够有效地避免以上问题,在紧急状况下能实时预警和紧急制动,保证结构施工全过程安全。
关键词 桥梁工程 移动模架 有限元分析 BIM技术中图分类号 U445 移动模架是一种自带模板、可在桥跨间自行移位,用于支撑和浇筑混凝土箱梁的大型制梁支撑体系。
移动模架施工技术因其能适应现浇连续梁的各种环境,且具有标准化作业、不受施工天气影响、适应性强、操作简单等特点而得到推广和应用[1 3]。
上行式移动模架承重的主梁系统位于桥面上方,施工占用桥下净空小,对低矮桥墩具有很强的适应性,且施工首跨和末跨或跨连续梁施工更方便(不需拆除主梁),能满足通过高压线等障碍物的净空要求,因此具有巨大优势[4],本文研究对象为上行式移动模架。
随着移动模架施工技术的广泛应用,其安全问题也逐渐凸显出来。
据初步统计,在某些线路投入的数十套移动模架中,约1/3以上发生过不同程度的安全事故。
UsingCoordinationMiddlewareforLocation-AwareComputing:ALimeCaseStudy
AmyL.Murphy1,2andGianPietroPicco21DipartimentodiElettronicaeInformazione,PolitecnicodiMilano,Italy
E-mail:picco@elet.polimi.it2DepartmentofComputerScience,UniversityofRochester,NY,USA
E-mail:murphy@cs.rochester.edu
Abstract.Thedecouplingbetweenbehaviorandcommunicationfos-teredbycoordinationbecomesofparamountimportanceinmobilecom-puting.Inthisscenario,however,coordinationtechnologyistypicallyusedtodealonlywiththeapplicationdatanecessarytoorchestratetheprocessactivities.Inthispaper,weargueinsteadthattheverysamecoordinationabstractionscanbeusedeffectivelytodealalsowithin-formationcomingfromthephysicalcontext—afundamentalaspectofmobilecomputingapplications.WecastourconsiderationsinLime,acoordinationmodelandmiddle-waredesignedformobilecomputing.Tosupportourargumentswithconcreteexamples,wereportaboutthedevelopmentofTuling,aproof-of-conceptapplicationenablingthetrackingofmobileusers.Thelessonslearnedduringdevelopmentenableustoassessthefeasibilityoftheap-proachandidentifynewresearchopportunities.
1IntroductionMobilecomputingdefinesachallengingenvironmentforsoftwaredevelopment.Communicationisenabledbywirelesslinks,whicharelessreliableandintrinsi-callydependentontherelativepositionsofthemobilepartiesincommunication.Similarly,locationaffectstheoverallcontextperceivedbyamobileunit,bycon-strainingnotonlytheavailablecommunicationparties,butalsothedataavail-ableforcomputation,thesetofaccessibleservices,andingeneraltheresourcesavailabletoacomponent.Ithasbeenobserved[13]thatsoftwaredevelopmentinthemobileenviron-mentcanbetackledsuccessfullybyexploitingacoordinationperspective.Thedecouplingbetweenbehaviorandcommunicationfosteredbycoordinationen-ablesonetoseparatetheapplicativebehaviorofcomponentsfromthecon-tinuouslychangingcontextinwhichtheyareimmersed.Examplesofsystemsthathaveappliedthisintuitiontodealwithphysicalmobilityofhostsorlog-icalmobilityofagentsincludeKlaim[10],xmiddle[7],Tucson[12],Mars[2],andLime[8].Inallofthesesystems,ashareddatastructure—typicallyatu-plespace—isusedtostorethedataavailabletomobileunitsandtorepresentnaturallythecontextavailabletothem.Nevertheless,allofthesesystemsfocus2AmyL.MurphyandGianPietroPiccoonprovidingsupportforcoordinationthroughacontextconsistingessentiallyofapplicationdata.Littleornosupportisprovidedforconstrainingtheapplicationbehaviorbasedalsoonthephysicalcontext.
Clearly,thisisalimitation.Dealingwithachangingphysicalcontextisfun-damentalinmanymobileapplications.Physicalcontextinformationcanbeverydiverse,andincludelocalsysteminformationsuchasbatterylevelorsignal-noiseratio,orenvironmentalinformationsuchaslightintensity,temperature,oram-bientnoise.Amongall,locationispossiblythemostrelevantcontextelement,inthatitoftenqualifiesthevaluesoftheothers.Forexample,atemperaturereadingbecomesmoremeaningfulwhenaccompaniedbytheidentityoftheroomwhereitwassensed.Thepoint,however,isthattheactionsofanapplicationcomponentinamobileenvironmentmaydependononeormoreofthesecontextinformationvaluesandmodelingphysicalcontextbecomesanecessity.
Attheoppositeextremeofcoordinationapproaches,severalmiddlewaresys-temshavebeenproposedthatexplicitlytackletheproblemofmanagingady-namicallychangingcontext.RelevantexamplesincludetheContextToolkit[3],Odyssey[11],Aura[5],Gaia[14],andOwl[4].Thefocusofthesesystemsisonallowingapplicationstoretrieveinformationaboutcontext,eitherproactively(bydirectlyqueryingsomecontextrepresentation)orreactively(bysubscribingtochangesinthecontextinformation).Themiddlewaretakescareofproperlydisseminatingthecontextinformationtotheinvolvedparties,andhencegreatlysimplifiesthemanagementofphysicalcontextusedinmobileapplications.Ontheotherhand,thesesystemsprovidelittleornosupportforrepresentingandmanagingthedatacontext,usedforcoordinatingthebehavioroftheapplicationcomponents.
Inthispaper,wearguethatthegapbetweenthetwoaforementionedperspec-tivescanbereduced,ifnoteliminated,byexploitingcoordinationabstractionsalsoforthemanagementofthephysicalcontext.Onceacquiredbyappropri-atesensors,contextinformationisessentiallylikeanyotherdata,andhencecanbetreatedassuchinadata-centriccoordinationapproach.Theverysameprimitivesusedtomanipulate,retrieve,orreacttoavailabledataforthesakeofcoordinationcannowbeusedfordealingwithphysicalcontextinformation.Thesetwotraditionallyseparatedimensionsareunifiedunderacommonsetofabstractions,simplifyingconsiderablythedesignandimplementationofmobileapplications.