排序方式: 共有17条查询结果,搜索用时 46 毫秒
1.
2.
1-bit压缩感知理论指出:对稀疏信号进行少量线性投影并对投影信号进行1-bit量化,该1-bit信号包含足够的信息,从而能对原始信号进行高精度重建.然而,当信号难以进行稀疏表达时,传统1-bit压缩感知算法无法精确重建原始信号.前期研究表明,分块稀疏模型作为一种特殊的结构型稀疏模型,对于难以用传统稀疏模型进行表达的信号具有较好的表达作用.本文提出了一种针对分块稀疏信号的1-bit压缩感知重建方法,该方法利用分块稀疏的统计特性对信号进行数学建模,通过变分贝叶斯推断方法进行信号重建并在光电容积脉搏波(photoplethysmography)信号上进行了实验验证.实验结果表明,与现有1-bit压缩感知重建方法相比,本文方法重建精度更高,且收敛速度更快. 相似文献
3.
蒋洪平 傅世年 彭军 程鹏 黄涛 李鹏 李芳 李健 刘华昌 刘美飞 孟鸣 孟才 慕振成 荣林艳 欧阳华甫 孙彪 王博 田建民 王标 王盛昌 姚远 徐韬光 徐新安 辛文曲 赵富祥 曾磊 周文中 《中国物理C(英文版)》2014,(8):73-77
In beam halo experiments, it is very important to correctly characterize the RFQ output proton beam. In order to simulate the beam dynamics properly, we must first know the correct initial beam parameters. We have used two different methods, quadrupole scans and multi-wire scanners to determine the transverse phase-space properties of the proton beam. The experimental data were analyzed by fitting to the 3-D nonlinear simulation code IMPACT. For the quadrupole scan method, we found that the RMS beam radius and the measured beam-core profiles agreed very well with the simulations. For the multi-wire scanner method, we choose the case of a matched beam. By fitting the IMPACT simulation results to the measured data, we obtained the Courant-Snyder parameters and the emittance of the beam. The difference between the two methods is about eight percent, which is acceptable in our experiments. 相似文献
4.
5.
椭圆、双曲线和抛物线是平面解析几何中的重要曲线。深刻理解它们的定义是掌握这些重要曲线的前提,椭圆、双曲线和抛物线的定义反映了这些曲线的本质。因此,它是理解这些曲线的概念,推导它们的方程和解决与它们有关的问题的根本依据。 相似文献
6.
在求极限中,我们经常碰到0/0型、∞/∞型、0·∞型、∞—∞型、以及0~0型、1~∞型、∞~0型等七种不定型式。求这七种不定型式的极限有许多方法,本文介绍以下几种中学数学中适用的方法。一约去公因式例1 求(x~2-2x+1)/(x~3-1) 解:在x→1的过程中,分子x~2-2x十1→0分母x~3-1→0,这是0/0型的不定式。∵x→1时x≠1,∴x-1≠0,可以利用因式分解约去 相似文献
7.
以AISI316泡沫金属为基体为太阳能甲烷重整反应制备出系列Ru基和Ni基催化活性吸收体(Ru/Al2O3/AISI316,Ni/Al2O3(MgO)/AISI316),着重利用XRD、TPR、TPD和CO2脉冲吸脱附等技术对所制整体式催化剂的表面特性进行了表征和分析.结果表明:以AISI316泡沫金属为基体可增加活性组分与涂层载体Al2O3的相互作用以及活性物种的分散度.对于Ni基催化活性吸收体,在涂层载体中添加MgO助剂可显著地提高Ni/Al2O3/AISI316的催化活性;Al2O3涂层载体含量的增加可提高活性组分NiO的分散性.相对Ni/Al2O3/AISI316,Ru/Al2O3/AISI316催化活性吸收体对CO2的吸附和活化能力更强,因而具有相对更高的催化活性. 相似文献
8.
9.
10.
The China ADS(C-ADS) project proposes to build a 1000 MW Accelerator Driven sub-critical System around 2032. The accelerator will work in CW mode with 10 mA in beam current and 1.5 GeV in final beam energy. The linac is composed of two major sections: the injector section and the main linac section. There are two diferent schemes for the injector section. The Injector-scheme is based on a 325 MHz RFQ and superconducting spoke cavities of the same RF frequency and the Injector-scheme is based on a 162.5 MHz RFQ and superconducting HWR cavities of the same frequency. The main linac design will be diferent for diferent injector choices. The two diferent designs for the main linac have been studied according to the beam characteristics from the diferent injector schemes. 相似文献