摘要:
Tetrahydrofurans suitable for use as starting materials in the synthesis of polyether polyols without causing coloration in the product polyether polyols can be obtained by contacting crude tetrahydrofurans with a mineral acid or a strongly acidic cation-exchange resin, followed by isolation through a simple distillation and/or rectification to obtain purified tetrahydrofurans.
摘要:
A method for computer aided detection of anatomical abnormalities in medical images includes providing a plurality of abnormality candidates and features of said abnormality candidates, and classifying said abnormality candidates as true positives or false positives using a hierarchical cascade of linear classifiers of the form sign(wTx+b), wherein x is a feature vector, w is a weighting vector and b is a model parameter, wherein different weights are used to penalize false negatives and false positives, and wherein more complex features are used for each successive stage of said cascade of classifiers.
摘要:
A reactive-diffusion method for estimating a diameter of an object of interest includes providing a volume of interest including a plurality of voxels, initializing at least two volumes of the volume of interest, wherein each of the voxels has at least two values corresponding to the at least two volumes of the volume of interest, respectively, performing a diffusion operation and a reaction operation on the voxels to adjust the at least two values, comparing, for each voxel, the at least two values to a threshold to assign each voxel to one of the at least two volumes, wherein the assignment of the voxels is a segmentation result, and estimating a diameter of the object of interest from the segmentation result, wherein the object of interest is represented by at least one of the at least two volumes but less than all the volumes.
摘要:
A method for differentiating pulmonary nodules in digitized medical images includes identifying an object of interest from a digital image of the lungs, computing a first distance map of each point of the object of interest, determining a seed point from the first distance map, starting from the seed point, growing a first region by adding successive adjacent layers of points until a background point is reached, and partitioning the first region into a nodule region and a non-nodule region.
摘要:
A method for segmenting digitized images includes providing a training set comprising a plurality of digitized whole-body images, providing labels on anatomical landmarks in each image of said training set, aligning each said training set image, generating positive and negative training examples for each landmark by cropping the aligned training volumes into one or more cropping windows of different spatial scales, and using said positive and negative examples to train a detector for each landmark at one or more spatial scales ranging from a coarse resolution to a fine resolution, wherein the spatial relationship between a cropping windows of a coarse resolution detector and a fine resolution detector is recorded.
摘要:
A method for computer aided detection of anatomical abnormalities in medical images includes providing a plurality of abnormality candidates and features of said abnormality candidates, and classifying said abnormality candidates as true positives or false positives using a hierarchical cascade of linear classifiers of the form sign(wTx+b), wherein x is a feature vector, w is a weighting vector and b is a model parameter, wherein different weights are used to penalize false negatives and false positives, and wherein more complex features are used for each successive stage of said cascade of classifiers.
摘要翻译:一种用于计算机辅助检测医学图像中的解剖异常的方法,包括提供所述异常候选的多个异常候选和特征,并且使用形式符号(w)的线性分类器的分级级联将所述异常候选分类为真阳性或假阳性 x + b),其中x是特征向量,w是加权向量,b是模型参数,其中不同的权重用于惩罚假否定和假肯定,并且其中更复杂的特征 用于分级器级联的每个连续阶段。
摘要:
A reactive-diffusion method for estimating a diameter of an object of interest includes providing a volume of interest including a plurality of voxels, initializing at least two volumes of the volume of interest, wherein each of the voxels has at least two values corresponding to the at least two volumes of the volume of interest, respectively, performing a diffusion operation and a reaction operation on the voxels to adjust the at least two values, comparing, for each voxel, the at least two values to a threshold to assign each voxel to one of the at least two volumes, wherein the assignment of the voxels is a segmentation result, and estimating a diameter of the object of interest from the segmentation result, wherein the object of interest is represented by at least one of the at least two volumes but less than all the volumes.
摘要:
A method for estimating a diameter of an object of interest, includes extracting a sub-volume of voxels around a marker identifying a location of the object of interest, and determining a segmentation result identifying an edge of the object of interest by a reactive-diffusion method. The method further includes performing a boundary check on the segmentation result to determine whether the object of interest is solitary, estimating a diameter of the object of interest from the segmentation result upon determining the object of interest to be solitary, and extracting the object of interest by performing ellipsoid fit on the sub-volume and estimating a diameter of the object of interest upon determining the object of interest to be non-solitary.
摘要:
A method for differentiating pulmonary nodules in digitized medical images includes identifying an object of interest from a digital image of the lungs, computing a first distance map of each point of the object of interest, determining a seed point from the first distance map, starting from the seed point, growing a first region by adding successive adjacent layers of points until a background point is reached, and partitioning the first region into a nodule region and a non-nodule region.
摘要:
A method for automatically estimating a measure of a nodule includes providing sliced image volume data comprising at least one marked position of the nodule, extracting a sub-volume from the sliced image volume data that includes the marked position, performing a figure-ground separation to determine a solid foreground of the sub-volume and a non-solid foreground of the sub-volume, determining a seed point corresponding to the nodule from each of the solid foreground and the non-solid foreground, selecting one of the seed point of the solid foreground or the seed point of the non-solid foreground, determining whether the selected seed point is solitary or non-solitary and performing region growing for non-solitary selected seed point, determining a segmentation of the selected seed point, estimating the measure of the nodule corresponding to the segmentation, and outputting the segmentation and an estimate of the measure of the nodule.