简介：把方法(IBM)和有限体积基于沉浸的边界优化因素pre的协议(FVOPC)计划，噪音繁殖在内并且在一把错流扇子的套外面的数字模拟被建立。不稳定的线性化的Euler方程被解决直接模仿飞行器声学的地。为了验证FVOPC，策划，一个模拟盒子：一个维的线性波浪繁殖问题用FVOPC计划，DRP计划和hoc计划被执行。FVOPC的结果在对分析答案的好同意，它比DRP和hoc计划的结果好。FVOPC比DRP和hoc计划是更少的分散和驱散。然后，噪音繁殖问题的数字模拟被执行。36紧缩的旋转噪音来源的噪音地与1000r/min的旋转速度被获得。吸收边界状况的PML为压抑数字思考被用于健全的远地边界条件。墙边界状况被用于套。结果证明在这块地里套墙和声波干扰上有思考。有IBM的FVOPC对在为压抑分散和驱散的复杂几何学下面的噪音繁殖问题合适，并且也把高顺序作为精确。

简介：non-Gaussian噪音驾驶的一个随机的消散的动态系统被调查。系统的一个一般近似佛克普朗克常数方程通过一条路径积分途径被导出。基于香农的信息熵，熵流动的准确时间依赖和系统的熵生产的定义在缺席并且面对非平衡被计算限制。现在的计算能被用来在熵流动和熵生产上解释消散的常数和non-Gaussian噪音的相互影响。

简介：BasedonthenoisesurveyinChina,theformula（H′=H+N-HN/120）ofISO/DIS1999.2（"Acous-tics-DeterminationofOccupationalnoiseexposureandestimationofnoise-inducedhearingimpairment,1985）wasappliedtothecalculationofthehearingthresholdlevelassociatedwithageandnoise（HTLAN）ofthenoise-impairedpeople.AccordingtotheGaussciandistribution,whenthenoise-exposurelevelLEX8hwas85,90,95,100dBandthehearingthresholdfrequencyisfrom0.5kto6kHz,theHTLANofnoise-exposedpeoplewithdifferentdurationofexposureanditsrelationvaluestothehearingthresholdfrequencyassociatedwithage（HTLA）wereobtained.TheISO/DIS1999.2hasbeenprovedtobeapplicableinChina.

简介：Thisworkdevelopsnear-optimalcontrolsforsystemsgivenbydifferentialequationswithwidebandnoiseandrandomswitching.Therandomswitchingismodeledbyacontinuous-time,time-inhomogeneousMarkovchain.Underbroadconditions,itisshownthatthereisanassociatedlimitproblem,whichisaswitchingjumpdiffusion.Usingnear-optimalcontrolsofthelimitsystem,wethenbuildcontrolsfortheoriginalsystems.Itisshownthatsuchconstructedcontrolsarenearlyoptimal.

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简介：Theemissionwavelengthofalaserisphysicallypredeterminedbythegainmediumused.Consequently,arbitrarywavelengthgenerationisafundamentalchallengeinthescienceoflight.Presentsolutionsincludeopticalparametricgeneration,requiringcomplexopticalsetupsandspectrallyslicedsupercontinuum,takingadvantageofasimplerfibertechnology:afixed-wavelengthpumplaserpulseisconvertedintoaspectrallyverybroadbandoutput,fromwhichtherequiredresultingwavelengthisthenopticallyfiltered.Unfortunately,thisprocessisassociatedwithaninherentlypoornoisefigure,whichoftenprecludesmanyrealisticapplicationsofsuchsupercontinuumsources.Here,weshowthatbyaddingonlyonepassiveopticalelement—ataperedphotoniccrystalfiber—toafixed-wavelengthfemtosecondlaser,onecaninaverysimplemannerresonantlyconvertthelaseremissionwavelengthintoanultra-wideandcontinuousrangeofdesiredwavelengths,withverylowinherentnoise,andwithoutmechanicalrealignmentofthelaser.Thisisachievedbyexploitingthedoubleinterplayofnonlinearityandchirpinthelasersourceandchirpandphasematchinginthetaperedfiber.Asafirstdemonstrationofthissimpleandinexpensivetechnology,wepresentafemtosecondfiberlasercontinuouslytunableacrosstheentirered–green–bluespectralrange.

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简介：Amode-lockedthulium-dopedfiberlaser(TDFL)basedonnonlinearpolarizationrotation(NPR)withdifferentnetanomalousdispersionisdemonstrated.Whenthecavitydispersionis-1.425ps~2,thenoise-like(NL)pulsewithcoherencespikewidthof406fsandpulseenergyof12.342nJisgeneratedatacenterwavelengthof2003.2nmwith3dBspectralbandwidthof23.20nm.Intheexperimentalperiodof400min,the3dBspectralbandwidthvariation,theoutputpowerfluctuation,andthecentralwavelengthshiftarelessthan0.06nm,0.04dB,and0.4nm,respectively,indicatingthattheNPR-basedTDFLoperatingintheNLregimeholdsgoodlong-termstability.

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