A statistical algorithm for the reconstruction from time sequence echocardiographic images is proposed in this paper. The ability to jointly restore the images and reconstruct the 3D images without blurring the bounda...A statistical algorithm for the reconstruction from time sequence echocardiographic images is proposed in this paper. The ability to jointly restore the images and reconstruct the 3D images without blurring the boundary is the main innovation of this algorithm. First, a Bayesian model based on MAP-MRF is used to reconstruct 3D volume, and extended to deal with the images acquired by rotation scanning method. Then, the spatiotemporal nature of ultrasound images is taken into account for the pa-rameter of energy function, which makes this statistical model anisotropic. Hence not only can this method reconstruct 3D ul-trasound images, but also remove the speckle noise anisotropically. Finally, we illustrate the experiments of our method on the synthetic and medical images and compare it with the isotropic reconstruction method.展开更多
Quantification of 3-dimensional (3-D) plant root architecture is one of the most important approaches to investigating plant root growth and its function in nutrient acquisition and utilization. However, no effective ...Quantification of 3-dimensional (3-D) plant root architecture is one of the most important approaches to investigating plant root growth and its function in nutrient acquisition and utilization. However, no effective methods have been reported hitherto to quantify 3-D root architecture parameters, making it difficult to further study the 3-D characteris- tics of the root system and its function. In the present study, we created a rapid algorithm to reconstruct 3-D root system images based on the basic structural features of such linear objects as roots, using 2-D root images taken by digital CCD cameras at multi- viewing angles. This method is very effective in the reconstruction of plant root system images, thus enabling us to obtain the digital model of 3-D root architecture and its 3-D skeleton, based on which some major root architecture parameters can be calculated. Using this method, we were able to ac- quire 3-D parameters of soybean root architecture whose root diameter was more than 0.3 mm, includ- ing tap root length, total root length, average basal root angle, ratio of root width to root depth, percent- age distribution of root length in different layers and root distribution in different 3-D regions of the growth medium. We also quantitatively analyzed the rela- tionship between different root architecture parame-ters and such plant nutrition parameters as soybean biomass and phosphorus (P) uptake. Our study may provide a new tool in studying the growth and nutri- tional functions of plant root systems.展开更多
基金Project supported by the National Basic Research Program (973) of0China (No. 2003CB716104), and Shanghai Science and TechnologyResearch Foundation (No. 034119820), China
文摘A statistical algorithm for the reconstruction from time sequence echocardiographic images is proposed in this paper. The ability to jointly restore the images and reconstruct the 3D images without blurring the boundary is the main innovation of this algorithm. First, a Bayesian model based on MAP-MRF is used to reconstruct 3D volume, and extended to deal with the images acquired by rotation scanning method. Then, the spatiotemporal nature of ultrasound images is taken into account for the pa-rameter of energy function, which makes this statistical model anisotropic. Hence not only can this method reconstruct 3D ul-trasound images, but also remove the speckle noise anisotropically. Finally, we illustrate the experiments of our method on the synthetic and medical images and compare it with the isotropic reconstruction method.
基金This work was jointly supported by the National Key Basic Research Funds of China(Grant No.2005CB120902)the National Natural Science Foundation of China(Grant No.30230220)the McKnight Foundation Collaborative Crop Research Program(Grant No.05-780).
文摘Quantification of 3-dimensional (3-D) plant root architecture is one of the most important approaches to investigating plant root growth and its function in nutrient acquisition and utilization. However, no effective methods have been reported hitherto to quantify 3-D root architecture parameters, making it difficult to further study the 3-D characteris- tics of the root system and its function. In the present study, we created a rapid algorithm to reconstruct 3-D root system images based on the basic structural features of such linear objects as roots, using 2-D root images taken by digital CCD cameras at multi- viewing angles. This method is very effective in the reconstruction of plant root system images, thus enabling us to obtain the digital model of 3-D root architecture and its 3-D skeleton, based on which some major root architecture parameters can be calculated. Using this method, we were able to ac- quire 3-D parameters of soybean root architecture whose root diameter was more than 0.3 mm, includ- ing tap root length, total root length, average basal root angle, ratio of root width to root depth, percent- age distribution of root length in different layers and root distribution in different 3-D regions of the growth medium. We also quantitatively analyzed the rela- tionship between different root architecture parame-ters and such plant nutrition parameters as soybean biomass and phosphorus (P) uptake. Our study may provide a new tool in studying the growth and nutri- tional functions of plant root systems.
