Search results for "Computer science"
showing 10 items of 22367 documents
Towards a Guidance System to Aid in the Dosimetry Calculation of Intraoperative Electron Radiation Therapy
2015
In Intraoperative Electron Radiation Therapy (IOERT), the lack of specific planning tools limits its applicability, the need for accurate dosimetry estimation and application during the therapy being the most critical. Recently, some works have been presented that try to overcome some of the limitations for establishing planning tools, though still an accurate guidance system that tracks, in real-time, the applicator and the patient is needed. In these surgical environments, the acquisition of an accurate 3D shape of the patient’s tumor bed in real-time is of high interest, as current systems make use of a 3D model acquired before the treatment. In this paper, an optical-based system is pre…
STUDENT GRAPHICAL INFORMATION LITERACY IN MATHEMATICS AND SCIENCE
2017
Among the most important 21st century skills that every student needs are the ability to work with information. The key for implementing competency based approach to learning will be related to how students' ability to apply skills acquired in, for example, mathematics can be transferred to other subject contexts. Newest OECD PISA results presented in 2016 show a recurring tendency that in Latvia there is a small number of students whose performance is in accordance to the 5th and 6th level of the framework. These two levels represent students' ability to apply deep thinking skills in new learning contexts. It is necessary to analyze the causes of this situation in order to identify opportu…
A Sub-Supersolution Approach for Robin Boundary Value Problems with Full Gradient Dependence
2020
The paper investigates a nonlinear elliptic problem with a Robin boundary condition, which exhibits a convection term with full dependence on the solution and its gradient. A sub- supersolution approach is developed for this type of problems. The main result establishes the existence of a solution enclosed in the ordered interval formed by a sub-supersolution. The result is applied to find positive solutions.
Inter-annotator agreement in spoken language annotation: Applying uα-family coefficients to discourse segmentation
2021
As databases make Corpus Linguistics a common tool for most linguists, corpus annotation becomes an increasingly important process. Corpus users do not need only raw data, but also annotated data, submitted to tagging or parsing processes through annotation protocols. One problem with corpus annotation lies in its reliability, that is, in the probability that its results can be replicable by independent researchers. Inter-annotation agreement (IAA) is the process which evaluates the probability that, applying the same protocol, different annotators reach similar results. To measure agreement, different statistical metrics are used. This study applies IAA for the first time to the Valencia E…
Reverse Catmull-Clark Subdivision
2006
Reverse subdivision consists in constructing a coarse mesh of a model from a finer mesh of this same model. In this paper, we give formulas for reverse Catmull-Clark subdivision. These formulas allow the constructing of a coarse mesh for almost all meshes. The condition for being able to apply these formulas is that the mesh to be reversed must be generated by the subdivision of a coarse mesh. Except for this condition, the mesh can be arbitrary. Vertices can be regular or extraordinary and the mesh itself can be arbitrary (triangular, quadrilateral…).
Étude d'un système de stéréo-vision hybride
2013
National audience; On considère dans ce travail un système de vision hybride fixe composé d'une caméra fisheye et d'une caméra PTZ dans un environnement rigide. Nous souhaitons être en mesure d'orienter la caméra mécanisée sur une cible visible depuis l'image omnidirectionnelle de manière à obtenir une image de bonne définition de l'objet d'intérêt à partir de la caméra PTZ. Nous proposons dans cet article d'utiliser la modélisation sphérique des images ainsi que les propriétés de la géométrie épipolaire afin d'initialiser la localisation de la cible dans la caméra PTZ.
Rethinking gender and technology within intersections in the Global South
2019
This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book examines mobile technology use in the Global South through the lens of intersectional understandings of power. It explores the integration of mobile phones in the lives of women from Gishu County in Kenya, and the meanings and symbolism attributed to this technology. The book deals with the material-feminist concept of social reproduction to understand the deepening precarity of the urban poor in Tanzania and their gendered responses to it. It explains the concept of young men’s financial inclusion linked to the proliferation of mobile money in Uganda. The book discusses th…
Attacking TrustZone on devices lacking memory protection
2021
AbstractARM TrustZone offers a Trusted Execution Environment (TEE) embedded into the processor cores. Some vendors offer ARM modules that do not fully comply with TrustZone specifications, which may lead to vulnerabilities in the system. In this paper, we present a DMA attack tutorial from the insecure world onto the secure world, and the design and implementation of this attack in a real insecure hardware.
Towards Automated Classification of Firmware Images and Identification of Embedded Devices
2017
Part 4: Operating System and Firmware Security; International audience; Embedded systems, as opposed to traditional computers, bring an incredible diversity. The number of devices manufactured is constantly increasing and each has a dedicated software, commonly known as firmware. Full firmware images are often delivered as multiple releases, correcting bugs and vulnerabilities, or adding new features. Unfortunately, there is no centralized or standardized firmware distribution mechanism. It is therefore difficult to track which vendor or device a firmware package belongs to, or to identify which firmware version is used in deployed embedded devices. At the same time, discovering devices tha…
Synchronizing Two Superconducting Qubits through a Dissipating Resonator
2021
A system consisting of two qubits and a resonator is considered in the presence of different sources of noise, bringing to light the possibility of making the two qubits evolve in a synchronized way. A direct qubit–qubit interaction turns out to be a crucial ingredient, as well as the dissipation processes involving the resonator. The detrimental role of the local dephasing of the qubits is also taken into account.