broadband emission 中文意思是什麼
broadband emission
解釋
帶外發射-
A large planar microphone array, which consists of 111 microphones, was successfully applied to obtain a two - dimensional mapping of the sound sources on a landing aircraft. the focus of study in this paper is on the landing gear noise source. the spectra, directivities and sound pressure levels of flap side - edge noise of 7 narrow - board commercial aircraft and 7 wide - board commercial aircraft are presented. it is found that the landing gear noise spectrum is broadband with some single tones in some cases. the directivity of the total sound pressure level of a landing gear noise resembles that of a horizontal dipole. the level differences between the various aircraft landing gears are larger than those expected from the airspeed differences. it is thus expected that the louder noise emission of the landing gears can be reduced by redesigning
應用由111個傳聲器組成的平面傳聲器陣列對當前流行的民用客機進場著陸過程中的機體噪聲源進行了實驗測量，本文對七架窄體客機和七架寬體客機的起落架噪聲進行了分析，得到了起落架噪聲的頻譜特性、指向特性和聲級變化.研究發現，起落架噪聲的頻譜是由寬頻隨機噪聲與一些較為明顯的單音噪聲源組成，起落架噪聲的指向性類似於一個水平放置的偶極子.不同飛機起落架噪聲的聲級相差較大，這說明可以通過重新結構設計降低起落架噪聲。 -
Abstract : a large planar microphone array, which consists of 111 microphones, was successfully applied to obtain a two - dimensional mapping of the sound sources on a landing aircraft. the focus of study in this paper is on the landing gear noise source. the spectra, directivities and sound pressure levels of flap side - edge noise of 7 narrow - board commercial aircraft and 7 wide - board commercial aircraft are presented. it is found that the landing gear noise spectrum is broadband with some single tones in some cases. the directivity of the total sound pressure level of a landing gear noise resembles that of a horizontal dipole. the level differences between the various aircraft landing gears are larger than those expected from the airspeed differences. it is thus expected that the louder noise emission of the landing gears can be reduced by redesigning
文摘:應用由111個傳聲器組成的平面傳聲器陣列對當前流行的民用客機進場著陸過程中的機體噪聲源進行了實驗測量，本文對七架窄體客機和七架寬體客機的起落架噪聲進行了分析，得到了起落架噪聲的頻譜特性、指向特性和聲級變化.研究發現，起落架噪聲的頻譜是由寬頻隨機噪聲與一些較為明顯的單音噪聲源組成，起落架噪聲的指向性類似於一個水平放置的偶極子.不同飛機起落架噪聲的聲級相差較大，這說明可以通過重新結構設計降低起落架噪聲。 -
The spectra parameters of these crystals can be calculated by the f - l formula, which show that the crystals are applicable for the tunable laser and femtosecond laser because of their large emission broadband ( fwhm 50nm )
用f ? l公式計算了晶體yb3 +的2f7 / 2 2f5 / 2能級躍遷的發射截面、輻射躍遷幾率、輻射壽命等光譜參數。
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