Jierong Cheng

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We present a method to separate clustered nuclei from fluorescence microscopy cellular images, using shape markers and marking function in a watershed-like algorithm. Shape markers are extracted using an adaptive H-minima transform. A marking function based on the outer distance transform is introduced to accurately separate clustered nuclei. With synthetic(More)
Snakes, or active contour models, have been widely used in image segmentation. However, most present snake models do not discern between positive and negative step edges. In this paper, a new type of dynamic external force for snakes named dynamic directional gradient vector flow (DDGVF) is proposed that uses this information for better performance. It(More)
In this paper, an automated method of boundary detection of the left ventricle (LV) is proposed. The method uses a watershed transform and morphological operation to locate the region containing the LV, then performs snake deformation with a multiscale directional edge map for the detection of the endocardial boundary of the LV
In the detection of the boundary of the left ventricle from echocardiographic images, the crucial step is to determine the region of interest (ROI) or the center point (CP) of the left ventricle. In this paper, a new algorithm is proposed for automatic detection of the ROI and CP of the left ventricle from echocardiographic images. The method makes use of(More)
Graphene was recently shown to support deep subwavelength surface plasmons at terahertz frequencies characterized by low energy loss and strong field localization, both highly desirable. The properties of graphene can be locally tuned by applying an external gate voltage or by the adsorption of organic molecules that lead to doping through charge transfer.(More)
Lung injury caused by influenza virus infection is widespread. Understanding lung damage and repair progression post infection requires quantitative spatiotemporal information on various cell types mapping into the tissue structure. Based on high content images acquired from an automatic slide scanner, we have developed algorithms to quantify cell(More)
The concept of an ultra-thin metasurface made of single layer of only-dielectric disks for successful phase control over a full range is demonstrated. Conduction loss is avoided compared to its plasmonic counterpart. The interaction of the Mie resonances of the first two modes of the dielectric particles, magnetic and electric dipoles, is tailored by the(More)