简介:分布式视频编码具有编码简单、高效压缩等特点,近些年国内外设计实现了多种分布式视频编码算法.本文提出一种基于变换域的分布式视频编码仿真测试软件设计方案,以测试QICF、CIF以4:2:0采样的YUV原始视频文件,通过改变量化参数、提取位平面参数改变视频文件传输比特率,以测试该算法在不同比特率下的率失真性能,通过更改量化表和运动预测搜索半径,搜索块大小,以适用不同序列更改设置,达到最佳性能.该方案可以验证分布式视频编码中各个模块的功能,并可以提出相应模块的各种改进算法验证其性能.
简介:介绍大型开放式网络课程(MOOC)教学模式及国际化的平台、优质的课程资源、低成本的学习费用以及学习者或同行之间的互动和互助学习等特点,从航海教育和培训的特点出发,探讨MOOC对航海教育和培训的适用性、可行性,提出在航海教育和培训中应用MOOC的建议。
简介:Theplowofthesubmarineplowingtrencherisoneofthemainfunctionalmechanisms,anditsoptimizationisveryimportant.Thedesignparametersplayaverysignificantroleindeterminingtherequirementsofthetowingforceofavessel.Amulti-objectivegeneticalgorithmbasedonanalyticalmodelsoftheplowsurfacehasbeenexaminedandappliedineffortstoobtainoptimaldesignoftheplow.Foraspecificsoilcondition,thedraftforceandmoldboardsurfaceareawhicharethekeyparametersintheworkingprocessoftheplowareoptimizedbyfindingthecorrespondingoptimalvaluesoftheplowbladepenetrationangleandtwosurfaceanglesofthemaincuttingbladeoftheplow.Parameterssuchasthemoldboardsideangleofdeviation,moldboardliftangle,angularvariationofthetangentline,andthespanninglengtharealsoanalyzedwithrespecttotheforceofthemoldboardsurfacealongsoilflowdirection.Resultsshowthattheoptimizedplowhasanimprovedplowperformance.Thedraftforcesofthemaincuttingbladeandthemoldboardare10.6%and7%,respectively,lessthantheoriginaldesign.ThestandarddeviationofGaussiancurvatureofmoldboardisloweredby64.5%,whichimpliesthatthesmoothnessoftheoptimizedmoldboardsurfaceismuchgreaterthantheoriginal.