掩蔽率 的英文怎麼說
中文拼音 [yǎnbìlǜ]
掩蔽率
英文
sheltering ratio-
In order to reduce the musical residual noise and the background noise, a speech enhancement method based on masking properties of the human auditory system is described. this method uses bark wavelet packet transform to simulate the frequency feature of human auditory model to get the threshold
本文以最大限度減少殘留噪聲和背景噪聲為目的，採用bark子波分析的方法模擬人耳基底膜的頻率分析特性來進行語音增強，重點進行模擬人耳聽覺掩蔽效應來確定除噪閾值的研究。A parametric psychoacoustic model based on critical band rate, level - dependent spreading function, non - linear superposition and forward masking was proposed
摘要提出了基於臨界頻帶率、依賴于強度的擴展函數、非線性迭加和前向掩蔽效應的參數心理聲學模型。At the initial stage of planar technique, b was employed as ideal diffusion impurity in base - region of npn si planar devices because of the match of its solid - solubility and diffusion coefficient in si with those of p in emission - region, and the good shield effect of sio2 film to b. but because of the relatively large solubility ( 5 1020 / cm3 at 1000 ) and the small diffusion coefficient, the linear slowly - changed distribution of acceptor b in pn junction can not be formed, which could not cater to the requirement of high - reversal - voltage devics. thereafter b - a1 paste - layer diffusion technology and close - tube ga - diffusion technology had been developed, while the former can lead to relatively large the base - region deviation and abruptly varied region in si, which caused severe decentralization of current amplification parameter, bad thermal stability and high tr ; the latter needed the relatively difficult pack technique, with poor repeatability, high rejection ratio, and poor diffusion quality and productio n efficiency
在平面工藝初期，由於b在硅中的固溶度、擴散系數與n型發射區的磷相匹配， sio _ 2對其又有良好的掩蔽作用，早被選為npn硅平面器件的理想基區擴散源，但b在硅中的固溶度大（ 1000時達到5 10 ~ （ 20 ） ，擴散系數小， b在硅中的雜質分佈不易形成pn結中雜質的線性緩變分佈，導致器件不能滿足高反壓的要求，隨之又出現了硼鋁塗層擴散工藝和閉管擴鎵工藝，前者會引起較大的基區偏差，雜質在硅內存在突變區域，導致放大系數分散嚴重，下降時間t _ f值較高，熱穩定性差；後者需要難度較大的真空封管技術，工藝重復性差，報廢率高，在擴散質量、生產效率諸方面均不能令人滿意。Choose the frequency from 14 to 16 bark as the embedding positions which below the masking threshold. then change the dct coefficient with the certain strength of
選用中低頻14 16bark段在掩蔽閾值以下的頻率分量作為嵌入點，對該嵌入點的dct系數以一定嵌入強度作修改來實現秘密信息的嵌入。In addition, a sophisticated mechanism derived from dwt coding is introduced to take into account several hvs phenomena such as gray - level sensitivity, noise sensibility around edges and isofrequency and nonisofrequency masking
另外，引入了一個由dwt編碼而來的復雜的機理來考慮幾個hvs現象如灰度級敏感度、邊緣噪音敏感度和頻率掩蔽。分享友人