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英语翻译成斯洛文尼亚语
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请大人将下面英语翻译成斯洛文尼亚语，重谢。急！急！ Fatigue crack detection in Al alloy plate by nonlinear time reversal method Abstract Based on the combination of the time reversal method and elastic nonlinear response, the imaging of fatigue cracks in 7075-T6 aluminum alloy plate is experimentally detected by a self-developed system. This system consists of piezoelectric transducers, arbitrary waveform generator, power amplifier, laser vibrometer, digital oscilloscope and computer. In experiments, four excitation signals (f=400kHz) are simultaneously emitted by four independent channels of arbitrary waveform generator and are applied to the PZT array. The frequency components of time reversal refocused signals around the fatigue crack are measured and analyzed. The experimental results show that the closer is the laser distant from the crack, the higher is the level of the peak amplitude of third harmonics. Therefore, third harmonic is a quite sensitive indicator of the presence of the fatigue crack. Through scanning the sample surface by the laser vibrometer, the two-dimensional contour plot of the peak amplitude of third harmonics can be achieved. So, the position of the crack can be located by the imaging. Keywords：Fatigue cracks; Detection; Nonlinear time reversal; 7075 Aluminum alloy plate Figure 1 Sketch of experimental system Figure 2. The waveforms from the TR experiment: (a) first response signal detected by laser vibrometer; (b) its local zoom; (c) the spectrum of the first response signal; (d) the TR refocused signal corresponding to figure (a); (e) its local zoom; (f) the spectrum of the TR refocused signal. Figure 3. TR refocused signal versus position of the laser vibrometer spot in a scanning process around the crack. Figure 4. The TR refocused signal filtered third harmonics (1.2MHz) corresponding to Figure 3, respectively. Figure 5. The two-dimensional contour plot of sample |
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3楼2009-10-26 22:30:16
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sdq5151(金币+50,VIP+0):感谢！以后还可能需要您的帮助 10-27 12:06
telomerase(金币-49,VIP+0):机译请注明！！！ 10-28 11:24
telomerase(金币-2,VIP+0):请下次注意！！机译必须注明！！！ 10-28 11:25
sdq5151(金币+50,VIP+0):感谢！以后还可能需要您的帮助 10-27 12:06
telomerase(金币-49,VIP+0):机译请注明！！！ 10-28 11:24
telomerase(金币-2,VIP+0):请下次注意！！机译必须注明！！！ 10-28 11:25
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Utrujenost crack odkrivanja na zlitine Al ploščo z nelinearno čas preobrata metoda Povzetek Glede na kombinacijo metode obrat čas in elastična nelinearna odgovor, slikanje razpok zaradi utrujenosti materiala v 7075-T6 aluminijaste plošča je poskusno zazna samostojno razvit sistem. Ta sistem je sestavljen iz piezoelektričnih pretvornikov, samovoljna valovno generator, power ojačevalnik, laser Merilnik vibracij, digitalnega osciloskopa in računalnik. V poskusih, štiri vzbujanje signalov (f = 400kHz), so hkrati oddajajo štirih neodvisnih kanalov samovoljne valovno generatorja in se uporabljajo za array PZT. Pogostost komponente časa preobrat osredotočene signalov okoli utrujenost tresk se merijo in analizirajo. Eksperimentalni rezultati kažejo, da je bližje laser oddaljeno od tresk, višja je stopnja največje amplitude tretjih harmonike. Zato je tretja harmonično precej občutljiv pokazatelj prisotnosti utrujenost tresk. Skozi skeniranje površino vzorca z laserjem Merilnik vibracij, dvo-dimenzionalni ploskvi obris vrha amplitude tretje harmonike mogoče doseči. Torej, se lahko položaj tresk nahaja slikanje. Ključne besede: utrujenost razpoke, zaznavanje, Nonlinear času preobrat; 7075 Aluminum alloy plate Slika 1 Skica eksperimentalnega sistema Slika 2. Oblike valov iz poskusa TR: (a) prvi odgovor signal zazna laser Merilnik vibracij; (b) njeni lokalni zoom, (c) spekter signala prvi odziv; (d) TR usmeriti signal, ki ustreza sliki (a); (e) njegovega lokalnega zoom, (f) spekter TR usmeriti signal. Slika 3. TR usmeriti signal v primerjavi položaj na kraju samem Merilnik vibracij laser skeniranja okoli tresk. Slika 4. TR usmeriti signal filtriran tretji harmonike (1.2MHz), ki ustreza sliki 3, respectively. Slika 5. Dvodimenzionalno obris ploskvi vzorca |
2楼2009-10-26 21:18:00
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