Search results for "Transform"
showing 10 items of 3975 documents
Content based segmentation of patterned wafers
2004
We extend our previous work on the image segmentation of electronic structures on patterned wafers to improve the defect detection process on optical inspection tools. Die-to-die wafer in- spection is based on the comparison of the same area on two neigh- boring dies. The dissimilarities between the images are a result of defects in this area of one of the dies. The noise level can vary from one structure to the other, within the same image. Therefore, seg- mentation is required to create a mask and apply an optimal thresh- old in each region. Contrast variation on the texture can affect the response of the parameters used for the segmentation. We show a method to anticipate these variation…
Fractional-Fourier-transform calculation through the fast-Fourier-transform algorithm.
1996
A method for the calculation of the fractional Fourier transform (FRT) by means of the fast Fourier transform (FFT) algorithm is presented. The process involves mainly two FFT’s in cascade; thus the process has the same complexity as this algorithm. The method is valid for fractional orders varying from −1 to 1. Scaling factors for the FRT and Fresnel diffraction when calculated through the FFT are discussed.
Accuracy of stereotactic coordinate transformation using a localisation frame and computed tomographic imaging
1999
The accuracy of coordinate transformation from a CT image to a stereotactic frame was investigated for stereotactic systems using a localisation frame and matrix-based coordinate transformation. The main source of error influencing calculation was input data, due to inaccurate calculation of the centres of the rods of the localisation frame in the CT image, and the propagation of this input error during subsequent matrix calculation. Systemic errors during matrix calculation do not exist, and rounding off errors were of subordinate importance compared to the input data error. The influence of input data error on coordinate transformation was studied by geometric methods, computer simulation…
<title>Human cell texture analysis with quincunx spline wavelet transform</title>
1999
Wavelet transforms are efficient tools for texture analysis and classification. Separable techniques are classically used but present several drawbacks. First, diagonal coefficients contain poor information. Second, the other coefficients contain useful information only if the texture is oriented in the vertical and horizontal directions. So an approach of texture analysis by non-separable transform is proposed. An improved interscale resolution is allowed by the quincunx scheme and this analysis leads to only one detail image where no particular orientation is favored. New orthogonal isotropic filters for the decomposition are constructed by applying McClellan transform on one dimension B-…
<title>Multiresolution description of range images through 2D quincunx wavelet analysis</title>
1999
In this paper, we present a method for performing a multi- scale analysis on range images by using the wavelet transform, that is capable of revealing multi-resolution information. An accurate non-contact optical system based upon laser triangulation is used to determine the depth information of the object being scanned. The resulting range image is treated as a gray-level image by using a multi- resolution approach based on the generalization of the cascade algorithm using the quincunx wavelet transform. The quincunx wavelet assures very fine analysis. This method allows reconstruction of non-subsampled images that correspond to decompositions previously done at chosen scales. Multi-resolu…
Wild-type JAK2 secondary acute erythroleukemia developing after JAK2-V617F-mutated primary myelofibrosis.
2009
A 54-year-old female patient developed acute erythroleukemia after an 8-year course of primary myelofibrosis. The latter harbors the JAK2-V617F mutation and was treated with hydroxyurea and anagrelide. A bone marrow trephine biopsy disclosed 2 morphologically distinct areas of chronic primary myelofibrosis and acute erythroleukemia. Microdissection and a separate molecular pathological analysis was performed. Although the activating JAK2-V617F mutation was not maintained in blasts of acute erythroleukemia, it was detectable in the chronic phase of primary myelofibrosis, indicating that this mutation did not play a role in the leukemic transformation of erythroid cells.
A Digital Watermarking Algorithm Based on Quantization of the DCT: Application on Medical Imaging
2013
International audience; The objective of this paper is to elaborate a new watermarking algorithm applied to the medical imaging. This algorithm must be invisible, robust and has a rate, relatively high, integrating data. The proposed method uses the standard JPEG compression for the integration of medical data. The insertion block is inserted just after the quantization phase. To control identification and eventually the correction (if possible) of the inserted data, we use a series of turbocodes to recover the inserted data, after application of several attacks. The simulation studies are applied on MRI medicals images.
New Inhabitants for the Re-use of Historical Territories in South-Eastern Sicily
2021
In spite of the multifaceted criticalities that characterise the Sicilian territory, South-Eastern Sicily appears to be of particular interest due to the active role that distinguishes it from the rest of the Island. The transformation processes taking place in South-Eastern Sicily, in fact, seem to be guided by new perspectives of sustainability, local development and good governance. The mix obtained from the extraordinary amount of tangible and intangible resources, from some favourable socio-cultural circumstances and from the creation of new transportation infrastructures, has contributed to promoting new forms of reuse of the historical building heritage by Italian and overseas invest…
Multiple Authentic Project-Based Experiences and Persistent Learning?
2019
This work-in-progress paper in the research category investigates students’ experiences of learning over two project-based courses, of which the first is taken during bachelor studies and the second is taken during master studies. The research goal was to explore if and how the first project experience was considered beneficial to the latter. A pilot interview was conducted and analyzed for qualitatively different themes. Transformative learning theory (TLT) is introduced as the theoretical framework because of its focus on persistent learning originating in transformations in meaning perspectives. The results are discussed in the context of TLT, and they inform curriculum design and resear…
Transformation of Loyalty to E-loyalty
2020
As everyday life moves to the Internet, many factors and components have come up, with the "e" and e-loyalty not an exception. The authors focused on the transformation of loyalty to e-loyalty. It is important to understand the main differences between consumer loyalty models and e-loyalty models in order to promote business development not only in the traditional environment but also in the online environment. Such research methods as comparative analysis, analysis of the scientific literature, content analysis were used. The main focus of the research was on comparing loyalty models in the traditional and e-environment to find out the peculiarities and main features of the e-environment. …