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181.
This paper presents a robust object tracking approach via a spatially constrained colour model. Local image patches of the object and spatial relation between these patches are informative and stable during object tracking. So, we propose to partition an object into patches and develop a Spatially Constrained Colour Model (SCCM) by combining the colour distributions and spatial configuration of these patches. The likelihood of the candidate object is given by estimating the confidences of the pixels in the ...  相似文献   
182.
本文提出了一种可供在多路IIR或者高阶IIR情况下进行联合过程估值的超稳定自适应算法。  相似文献   
183.
文中提出一个V/Q变换的广义跨导概念,并应用在开关电容阻抗模拟中。使用V/Q变换器,可以用电压传递函数实现所希望的阻抗函数。由此概念出发,分别导出了前差FD,后差BD和双线性S/Z变换的三种接地开关电容频变负阻SC-FDNR电路。如果所选用的电压传递函数电路对杂散电容不灵敏,那么实现的模拟阻抗电路对杂散电容也是不灵敏的。作为文中的一个例子,用FD-FDNR电路组成一个谐振回路,实验表明其频响特性与理论分析相一致。  相似文献   
184.
为了进一步提高微波滤波器的品质性能,增强其应用性,提出了一种新型的C型环缺陷地结构(DGS-Defected Ground Structure)单元,该单元几何图形简单,可减小滤波器尺寸。经过对C型环DGS单元带阻特性的分析仿真,得到了最佳性能的仿真模型。实验结果表明,C型环缺陷地结构单元可获得极窄的阻带(约1GHz),由C型环单元构成的滤波器Q值可达130.2。  相似文献   
185.
利用两路平行的刻有长周期光栅(LPWG)波导间耦合的理论模型,研究了LPWG波导光滤波器,利用弱耦合实现高耦合效率和窄带滤波的方法,设计了一个窄带光滤波器。仿真结果表明,在1 530~1 560 nm范围,能实现单一的带通、带阻互补滤波输出,3 dB带宽为1 nm,耦合效率高达98%。  相似文献   
186.
设计了一种小型化的低温共烧陶瓷(LTCC)滤波器,该滤波器电路由电容耦合的二阶谐振腔组成。设计了该滤波器的三维多层结构,利用组件间的耦合效应,产生一个传输零点,提高了滤波器性能。仿真结果表明,该滤波器中心频率为3.41GHz,相对带宽为5.9%(200MHz),体积为3.8mm×2.8mm×0.8mm,在S波段的通讯,雷达等射频系统有广泛的应用。  相似文献   
187.
The periodic structure of the underlying support of paintings on canvas can become quite prominent and disturbing in high resolution digital recordings. In this paper, we construct a new model and method for the digital removal of canvas which is considered as a noise component superimposed on the painting artwork. The high resolution of the images prohibits the efficient application of existing adaptive denoising filters. Hence, a two-step approach is proposed. First a (smoothing) Wiener filter is applied to the complete image. The second step consists of a spatially adaptive extension with low-complexity to obtain a generic digital canvas removal filter.  相似文献   
188.
In this report, the in vitro metabolism of Strychnos alkaloids was investigated using liquid chromatography/high‐resolution mass spectrometry for the first time. Strychnine and brucine were selected as model compounds to determine the universal biotransformations of the Strychnos alkaloids in rat liver microsomes. The incubation mixtures were separated by a bidentate‐C18 column, and then analyzed by on‐line ion trap/time‐of‐flight mass spectrometry. With the assistance of mass defect filtering technique, full‐scan accurate mass datasets were processed for the discovery of the related metabolites. The structural elucidations of these metabolites were achieved by comparing the changes in accurate molecular masses, calculating chemical component using Formula Predictor software and defining sites of biotransformation based upon accurate MSn spectral information. As a result, 31 metabolites were identified, of which 26 metabolites were reported for the first time. These biotransformations included hydroxylation, N‐oxidation, epoxidation, methylation, dehydrogenation, de‐methoxylation, O‐demethylation, as well as hydrolysis reactions. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
189.
The magnetic filtration theory was evaluated to intensify the filtration of industrial fluids by magnetic filters. Effects of filtration velocity and external magnetic field intensity on filter performance were investigated and the dependence of the logarithmic efficiency coefficient on filtration velocity was questioned. It was concluded that change in the magnetic susceptibility of the dispersion particles, caused by external magnetic field, and change in the flow rate properties of the liquid alongside the filter pores are the most essential factors to be considered in the design, development, and modeling of magnetic filtration systems in various industrial areas.  相似文献   
190.
Chinese calligraphy is a unique visual art, and is still emitting fascinating artistic brilliance and charm. The artistic beauty of Chinese calligraphy is constituted by two elements, i.e., form and spirit, which attract continual attentions by calligraphy artists. In this paper, we present Shear-Guided filter to extract the artistic information. Shear-Guided filter is designed by combining the shear transformation and the guided filter. It has both the edge-preserving smoothing property from the guided filter and the linear multidirectional property from the shear transformation. Shear-Guided filter can extract more spirit information from the calligraphy images, especially in the half-dry strokes. Furthermore, the previous evaluation parameters consider all pixels equally, which is against the truth. Here we put forward three new parameters to solve this issue. Finally, experiments show that Shear-Guided filter can extract the information of form and spirit more accurately, and the new evaluation parameters have better performances in evaluation.  相似文献   
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