João Batista S. de Oliveira

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We present an algorithm for computing a robust adaptive polygonal approximation of an implicit curve in the plane. The approximation is adapted to the geometry of the curve because the length of the edges varies with the curvature of the curve. Robustness is achieved by combining interval arithmetic and automatic differentiation.
Meningiomas are tumors originating from menin-gothelial cells of the arachnoid membrane and are benign in most cases 1-3 , corresponding to about 15% to 18% of all primary tumors of the central nervous system (CNS) 3,4. Ex-tracranial metastases of meningiomas are rare and occur in less than 1 per 1000 cases 3-5. According to the WHO criteria , the(More)
This paper describes two approaches to the problem of automatically placing document items on pages of some output device. Both solutions partition the page into regions where each item is to be placed, but work on different input data according to the application: One approach assumes that previously defined rectangular items are to be placed freely on the(More)
Most methods for computing offsets and bisectors of parametric curves are based on a local formulation of the distance to a curve. As a consequence, the computed objects may contain spurious parts and components, and have to be trimmed. We approach these problems as global optimization problems, and solve them using interval arithmetic, thus generating(More)
Recent advances in digital press technology have enabled the creation of high-quality personalized documents, with the potential of generating an entire batch of one-of-a-kind documents. Even though digital presses are capable of printing such document sets as fast as they would print regular press jobs, raster image processing might possibly be performed(More)
This paper proposes an extension of the XSL-FO standard which allows the specification of an unlimited number of arbitrarily shaped page regions. These extensions are built on top of XSL-FO 1.1 to enable flow content to be laid out into arbitrary shapes and allowing for page layouts currently available only to desktop publishing software. Such a proposal is(More)
Adaptive documents undergo many transformations during their generation, including insertion and deletion of content. One major problem in this scenario is the preservation of the aesthetic qualities of the document during those transformations.As adaptive documents are instances of a template, the aesthetic quality of an instance with respect to the(More)