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71.
将改进的基于流形学习的超分辨率重建与基于梯度约束的正则化重建结合起来,提出一种新的单帧图像超分辨率重建算法.该算法首先针对基于流形学习的超分辨率重建,提出新的特征提取方法,联合归一化亮度与平稳小波变换细节子带系数两个特征矢量,提高重建性能;然后将学习得到的高分辨率图像作为初始估计,将其梯度作为目标梯度域,进行基于梯度约束的正则化重建,得到最终的高分辨率图像.与现有的一些算法相比,文中算法无论在视觉效果还是客观评价上都具有较好的重建性能. 相似文献
72.
人工神经网络已成功应用到实际的故障诊断系统中,但大多主要用于单故障诊断情形。实际应用中,多故障同时出现的情况却普遍存在。基于神经网络的方法,构造了一种用于既能诊断单故障,又能诊断多故障的模型。通过实例与传统的诊断模型进行对比,说明了所提出诊断模型的可行性和有效性。 相似文献
73.
空心莲子草吸附钴离子前后溶液pH值的变化及其红外光谱研究 总被引:6,自引:0,他引:6
用PH计和红外光谱研究了空心莲子草对Co(NO3)2的生物吸附特性,发现空心莲子草对Co^2 具有有较强的吸附能力,在达到饱和吸附前,其吸附量随Co^2 的起始浓度的增加而增加,吸附前的PH值及红外光谱表明;在吸附过程中,羟基和氨基起重要作用,Co^2 与生物材料中的氢(可能是羟基氨)发生了交换,且化学吸附和物理吸附同时起作用。 相似文献
74.
对移动载体的自动跟踪技术是自动控制领域的一个核心问题.文章以GPS定位技术、直流伺服技术为基础,研究设计一套能够对移动目标实行自动跟踪的定向天线控制系统.该系统具有机动性强、稳定可靠性高等特点,解决了定向天线对准难的问题. 相似文献
75.
时效对Cu-Cr-Zr-C-RE合金显微硬度及导电率的影响 总被引:1,自引:0,他引:1
研究了冷变形后时效温度和时间对用喷铸成形得到的名义成分为Cu-0.2Cr-0.5Zr-0.04RE(55%wtLa+45wt%Ce)的合金显微硬度和导电率的影响。结果表明,在470℃时效1h,显微硬度达到Hv100172.9,导电率达到80.7%IACS,此时显微硬度和导电率的配合较好。 相似文献
76.
Synapsin I bundles F-actin in a phosphorylation-dependent manner 总被引:12,自引:0,他引:12
Synapsin I is a neuron-specific phosphoprotein localized to the cytoplasmic surface of synaptic vesicles. This phosphoprotein is a major substrate for cyclic AMP-dependent and calcium/calmodulin-dependent protein kinases. Its state of phosphorylation can be altered both in vivo and in vitro by a variety of physiological and pharmacological manipulations known to affect synaptic function. Recent direct evidence suggests that it may be involved in the regulation of neurotransmitter release from the nerve terminal. In the nerve terminal, synaptic vesicles are embedded in a cytoskeletal network, consisting in part of actin. We report here the ability of the dephospho-form of synapsin I to bundle F-actin. This bundling activity is reduced when synapsin I is phosphorylated by cAMP-dependent protein kinase and virtually abolished when it is phosphorylated by calcium/calmodulin-dependent protein kinase II or by both kinases. These results, demonstrating an interaction of synapsin I with actin in vitro, support the possibility that synapsin I is involved in clustering of synaptic vesicles at the presynaptic terminal and that the phosphorylation of synapsin I may be involved in regulating the translocation of synaptic vesicles to their sites of release. 相似文献
77.
A thermal gravimetric method is described for evaluating the kinetics of cell size-dependent decomposition and lifetime estima- tion for microcellular tissue engineering scaffolds made of biodegradable polylactic acid(PLA)foams.PLA foam cell sizes from 550 to 20?m were fabricated experimentally using a solvent-free solid-state foaming technique under saturation pressures from 1 to 5 MPa.The thermal properties of the PLA foams with respect to the cell sizes were measured using thermal gravimetric analy- sis in a nitrogen atmosphere and the activation energy and pre-exponential factor were derived to evaluate the decomposition ki- netics and estimate lifetime.It was found that small cell sizes can be achieved under high saturation pressures and that the thermal stability of PLA decreases after the fabrication process.The cell size-dependent thermal stability and degradation rate indicate that a PLA foam of larger cell sizes has a shorter degradation time,a few tenths that of the PLA raw material,at a temperature of 37°C. The results suggest that it is feasible to optimize fabrication parameters to obtain appropriate cell sizes and lifetimes that satisfy the application requirements for various organs.This study provides the basis for precise scaffold design and quantitative analysis of PLA foams in tissue engineering applications. 相似文献
78.
A new method based on the combining of the wavelet theory with the fractal theory and named wavelet fractal peak position method (WFPPM) is introduced to extract the number of the components and the relevant peak positions from overlapping signals in chemistry .The overlapping signal is first transformed into continuous wavelet transform value of time domain in certain dilation range via continuous wavelet transform (CWT),and then changed into capacity dimensions (Dc),The number of the components and the relevant positions of overlapping peaks can be identified easily according to the change of Dc.An investigation concerning the influence of different dilation ranges on the peak positions extracted by WFPPM is also provided .Studies show that the WFPPM is an efficient tool for extracting the peak positions and identifying the number of peaks from unresoloved signals,even when this kind of overlapping is significantly serious,Relative errors of lless than 1.0% in peak positions are found when WFPPM is used in the processing of the cadmium (Ⅱ)-indium(Ⅲ) mixture system .The analytical results demonstrate that the desired peak positions can be extracted conveniently ,accurately and rapidly from an unresoled signal via WFPPM,Tremendous developing and applications based on currently reported WFPPM in extracting overlapping signals would be expected in the near future. 相似文献
79.
研究了具可变时滞的随机系统dx(t)=[F(t,x(t),x(t-δ1(t)))+Δf(t,x(t),x(t-δ2(t)))]dt+g(t,x(t),x(t-δ3(T)))dw(t)的p阶均值指数稳定性与几乎必然指数稳定性,引入对应的随机系统(无时滞与扰动)dx(t)=f(t,x(t),x(t))dt+g(t,x(t),x(t))dw(t)并假设它是指数稳定的,应用Razumikhin技巧证明了当时滞δi(t)(i=1,2,3)与扰动Δf充分小时,原随机时滞系统仍指数稳定. 相似文献
80.
Fluid inclusions evidence for differential exhumation of ultrahigh pressure metamorphic rocks in the Sulu terrane 总被引:6,自引:0,他引:6
FAN Hongrui GUO Jinghui HU Fangfang CHU Xuelei CHEN Fukun & JIN Chengwei State Key Laboratory of Lithosphere Tectonic Evolution Key Labo- ratory of Mineral Resources Institute of Geology Geophysics Chi- nese Academy of Sciences Beijing China Correspondence should be addressed to Fan Hongrui 《科学通报(英文版)》2005,50(11):1139-1148
Since the discovery of coesite and diamond inclusions in eclogites from the Dabie-Sulu orogen, east-central China[1―3], this largest ultrahigh pressure (UHP) metamor- phic terrane in the world has attracted extensive scientific interests. A number of hydrous minerals such as zoisite, phengite, magnesite and talc have been found in the UHP rocks, showing that fluids have played an important role in this type of extreme metamorphic evolution[4―8]. Sev-eral techniques have been applied to th… 相似文献