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Recovery of Transient Signals in Noise by OptimalThresholding in Wavelet Domain
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作者 梅文博 《Journal of Beijing Institute of Technology》 EI CAS 1997年第3期274-279,共6页
:研究用离散子波变换复原被加性高斯白噪声污染的瞬态信号.在子波域中提出了一种最佳门限方法,该方法涉及到对于波系数的假设检验,利用似然比、奈曼,皮尔逊准则和最小均方差设计该门限,计算机仿真证明,该方法在较低信噪比下复原... :研究用离散子波变换复原被加性高斯白噪声污染的瞬态信号.在子波域中提出了一种最佳门限方法,该方法涉及到对于波系数的假设检验,利用似然比、奈曼,皮尔逊准则和最小均方差设计该门限,计算机仿真证明,该方法在较低信噪比下复原信号的有效性. 展开更多
关键词 n (Department of Electrical and Electronic Enginhaerhg University of Central Lancashire Preston PR1 2HE England) Abstract: the recovery of transient signals corrupted by additive white Gaussian noise by means of the discrete wavelet transform was studi
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The influence of desiccation on the recovery process of nitrogenase activity in restored biological soil crusts
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作者 Jiaoli Zheng Shuangshuang Li +1 位作者 Chengrong Peng Dunhai Li 《Science China(Life Sciences)》 SCIE CAS CSCD 2017年第11期1283-1285,共3页
Dear Editor,Biological soil crusts(BSCs),a layered structure formed by associations of soil organisms and topsoil,dominate arid and semiarid areas and serve important ecological functions in these areas(Eldridge and G... Dear Editor,Biological soil crusts(BSCs),a layered structure formed by associations of soil organisms and topsoil,dominate arid and semiarid areas and serve important ecological functions in these areas(Eldridge and Greene,1994).Nitrogen fixation by BSCs is the main source of N in arid and semi-arid ecosystems.Desiccation is the most notable factor that influences BSCs,which recover physiological activity only after moistening.By influencing the amount of carbohydrates, 展开更多
关键词 the influence DESICCATION the recovery process nitrogenase activity restored biological soil crusts
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The Recovery Begins
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作者 SHEILA A.SMITH 《Beijing Review》 2011年第13期20-20,共1页
Japan faces challenges as it begins to rebuild Japan faces atremendous challenge as it seeks to recover from the effects of the March 11 earthquake and tsunami.The most immediate challenge,of course。
关键词 the recovery Begins
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A Case Study of Tianjin on the Recovery and Reconstruction of Large Cities after Earthquake
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《Natural Disaster Reduction in China》 1997年第2期48-54,共7页
关键词 A Case Study of Tianjin on the recovery and Reconstruction of Large Cities after Earthquake
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