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排序方式: 共有154条查询结果,搜索用时 15 毫秒
1.
Pixel-clarity-based multifocus image fusion 总被引:4,自引:0,他引:4
Due to the limited depth-of-field of optical lenses, it is difficult to get an image with all objects in focus. One way to overcome this problem is to take several images with different focus points and combine them into a single composite which contains all the regions full focused. This paper describes a pixel-clarity-based multifocus image fusion algorithm. The characteristic of this approach is that the pixels of the fused image are selected from the clearest pixels in the input images according to pixel clarity criteria. For each pixel in the source images, the pixel clarity is calculated. The fusion procedure is performed by a selection mode according to the magnitude of pixel clarity. Consistency verification is performed on the selected pixels. Experiments show that the proposed algorithm works well in multifocus image fusion. 相似文献
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Reference-frame-independent quantum key distribution of wavelength division multiplexing with multiple quantum channels 下载免费PDF全文
Zhongqi Sun 《中国物理 B》2021,30(11):110303-110303
Reference-frame-independent quantum key distribution (RFI-QKD) can allow a quantum key distribution system to obtain the ideal key rate and transmission distance without reference system calibration, which has attracted much attention. Here, we propose an RFI-QKD protocol based on wavelength division multiplexing (WDM) considering finite-key analysis and crosstalk. The finite-key bound for RFI-QKD with decoy states is derived under the crosstalk of WDM. The resulting secret key rate of RFI-QKD, which is more rigorous, is obtained. Simulation results reveal that the secret key rate of RFI-QKD based on WDM is affected by the multiplexing channel number, as well as crosstalk between adjacent channels. 相似文献
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根据等效颗粒散射模型,运用经典的Mie理论,对生物组织的散射相函数、各向异性因子及散射系数进行了数值计算.计算结果表明:可见光照射生物组织时,各向异性因子、散射系数随等效颗粒直径增大而增大;等效颗粒直径较小时,各向异性因子、散射系数随入射光波长增大而单调减小;随着等效颗粒直径增大,各向异性因子、散射系数随入射光波长变化不再具有单调性.上述计算结果可合理解释公布的实验结果.
关键词:
生物组织
散射
Mie理论
等效颗粒 相似文献
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An Improved Computing Method for Analysing the Spatial Resolved Reflectance from Biological Tissues 下载免费PDF全文
A mathematical expression of refiectance point-spread function, which is defined as the spatial distribution of light diffuse-reflected from bio-tissues irradiated by an infinitely narrow photon beam, is derived from the difusion approximation (DA) theory. With the introduction of reflectance point-spread function to describe the reflectance characteristics of bio-tissues, the convolution method is used to calculate the spatial resolved reflectance from dense and thick tissues irradiated by different photon beams. This is called the DA based convolution method and is used to calculate the responses of the semi-infinite bio-tissues irradiated by a Gaussian beam and a flat beam with different beam radius. The calculation results show that the DA based convolution method has much higher computing efficiency compared to the Monte Carlo method. 相似文献
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磁性高分子微球用于固定化酶的研究进展:生物材料结构及?… 总被引:1,自引:0,他引:1
磁性高分子微球是近20年来发展起来的一种新型功能高分子材料,并已在生物化工、细胞学、生物医学工程等领域得到了广泛应用。本文主要介绍磁性高分子微球的制备和性质以及在固定化酶中的应用。 相似文献