475 research outputs found

    E-Learning

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    E-learning enables students to pace their studies according to their needs, making learning accessible to (1) people who do not have enough free time for studying - they can program their lessons according to their available schedule; (2) those far from a school (geographical issues), or the ones unable to attend classes due to some physical or medical restriction. Therefore, cultural, geographical and physical obstructions can be removed, making it possible for students to select their path and time for the learning course. Students are then allowed to choose the main objectives they are suitable to fulfill. This book regards E-learning challenges, opening a way to understand and discuss questions related to long-distance and lifelong learning, E-learning for people with special needs and, lastly, presenting case study about the relationship between the quality of interaction and the quality of learning achieved in experiences of E-learning formation

    Application of novel technologies for the development of next generation MR compatible PET inserts

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    Multimodal imaging integrating Positron Emission Tomography and Magnetic Resonance Imaging (PET/MRI) has professed advantages as compared to other available combinations, allowing both functional and structural information to be acquired with very high precision and repeatability. However, it has yet to be adopted as the standard for experimental and clinical applications, due to a variety of reasons mainly related to system cost and flexibility. A hopeful existing approach of silicon photodetector-based MR compatible PET inserts comprised by very thin PET devices that can be inserted in the MRI bore, has been pioneered, without disrupting the market as expected. Technological solutions that exist and can make this type of inserts lighter, cost-effective and more adaptable to the application need to be researched further. In this context, we expand the study of sub-surface laser engraving (SSLE) for scintillators used for PET. Through acquiring, measuring and calibrating the use of a SSLE setting we study the effect of different engraving configurations on detection characteristics of the scintillation light by the photosensors. We demonstrate that apart from cost-effectiveness and ease of application, SSLE treated scintillators have similar spatial resolution and superior sensitivity and packing fraction as compared to standard pixelated arrays, allowing for shorter crystals to be used. Flexibility of design is benchmarked and adoption of honeycomb architecture due to geometrical advantages is proposed. Furthermore, a variety of depth-of-interaction (DoI) designs are engraved and studied, greatly enhancing applicability in small field-of-view tomographs, such as the intended inserts. To adapt to this need, a novel approach for multi-layer DoI characterization has been developed and is demonstrated. Apart from crystal treatment, considerations on signal transmission and processing are addressed. A double time-over-threshold (ToT) method is proposed, using the statistics of noise in order to enhance precision. This method is tested and linearity results demonstrate applicability for multiplexed readout designs. A study on analog optical wireless communication (aOWC) techniques is also performed and proof of concept results presented. Finally, a ToT readout firmware architecture, intended for low-cost FPGAs, has been developed and is described. By addressing the potential development, applicability and merits of a range of transdisciplinary solutions, we demonstrate that with these techniques it is possible to construct lighter, smaller, lower consumption, cost-effective MRI compatible PET inserts. Those designs can make PET/MRI multimodality the dominant clinical and experimental imaging approach, enhancing researcher and physician insight to the mysteries of life.La combinación multimodal de Tomografía por Emisión de Positrones con la Imagen de Resonancia Magnética (PET/MRI, de sus siglas en inglés) tiene clara ventajas en comparación con otras técnicas multimodales actualmente disponibles, dada su capacidad para registrar información funcional e información estructural con mucha precisión y repetibilidad. Sin embargo, esta técnica no acaba de penetrar en la práctica clínica debido en gran parte a alto coste. Las investigaciones que persiguen mejorar el desarrollo de insertos de PET basados en fotodetectores de silicio y compatibles con MRI, aunque han sido intensas y han generado soluciones ingeniosas, todavía no han conseguido encontrar las soluciones que necesita la industria. Sin embargo, existen opciones todavía sin explorar que podrían ayudar a evolucionar este tipo de insertos consiguiendo dispositivos más ligeros, baratos y con mejores prestaciones. Esta tesis profundiza en el estudio de grabación sub-superficie con láser (SSLE) para el diseño de los cristales centelladores usados en los sistemas PET. Para ello hemos caracterizado, medido y calibrado un procedimiento SSLE, y a continuación hemos estudiado el efecto que tienen sobre las especificaciones del detector las diferentes configuraciones del grabado. Demostramos que además de la rentabilidad y facilidad de uso de esta técnica, los centelladores SSLE tienen resolución espacial equivalente y sensibilidad y fracción de empaquetamiento superiores a las matrices de centelleo convencionales, lo que posibilita utilizar cristales más cortos para conseguir la misma sensibilidad. Estos diseños también permiten medir la profundidad de la interacción (DoI), lo que facilita el uso de estos diseños en tomógrafos de radio pequeño, como pueden ser los sistemas preclínicos, los dedicados (cabeza o mama) o los insertos para MRI. Además de trabajar en el tratamiento de cristal de centelleo, hemos considerado nuevas aproximaciones al procesamiento y transmisión de la señal. Proponemos un método innovador de doble medida de tiempo sobre el umbral (ToT) que integra una evaluación de la estadística del ruido con el propósito de mejorar la precisión. El método se ha validado y los resultados demuestran su viabilidad de uso incluso en conjuntos de señales multiplexadas. Un estudio de las técnicas de comunicación óptica analógica e inalámbrica (aOWC) ha permitido el desarrollo de una nueva propuesta para comunicar las señales del detector PET insertado en el gantry a un el procesador de señal externo, técnica que se ha validado en un demostrador. Finalmente, se ha propuesto y demostrado una nueva arquitectura de análisis de señal ToT implementada en firmware en FPGAs de bajo coste. La concepción y desarrollo de estas ideas, así como la evaluación de los méritos de las diferentes soluciones propuestas, demuestran que con estas técnicas es posible construir insertos de PET compatibles con sistemas MRI, que serán más ligeros y compactos, con un reducido consumo y menor coste. De esta forma se contribuye a que la técnica multimodal PET/MRI pueda penetrar en la clínica, mejorando la comprensión que médicos e investigadores puedan alcanzar en su estudio de los misterios de la vida.Programa Oficial de Doctorado en Ingeniería Eléctrica, Electrónica y AutomáticaPresidente: Andrés Santos Lleó.- Secretario: Luis Hernández Corporales.- Vocal: Giancarlo Sportell

    Recent Application in Biometrics

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    In the recent years, a number of recognition and authentication systems based on biometric measurements have been proposed. Algorithms and sensors have been developed to acquire and process many different biometric traits. Moreover, the biometric technology is being used in novel ways, with potential commercial and practical implications to our daily activities. The key objective of the book is to provide a collection of comprehensive references on some recent theoretical development as well as novel applications in biometrics. The topics covered in this book reflect well both aspects of development. They include biometric sample quality, privacy preserving and cancellable biometrics, contactless biometrics, novel and unconventional biometrics, and the technical challenges in implementing the technology in portable devices. The book consists of 15 chapters. It is divided into four sections, namely, biometric applications on mobile platforms, cancelable biometrics, biometric encryption, and other applications. The book was reviewed by editors Dr. Jucheng Yang and Dr. Norman Poh. We deeply appreciate the efforts of our guest editors: Dr. Girija Chetty, Dr. Loris Nanni, Dr. Jianjiang Feng, Dr. Dongsun Park and Dr. Sook Yoon, as well as a number of anonymous reviewers

    NASA Tech Briefs, August 2008

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    Customizable Digital Receivers for Radar Two-Camera Acquisition and Tracking of a Flying Target Visual Data Analysis for Satellites A Data Type for Efficient Representation of Other Data Types Hand-Held Ultrasonic Instrument for Reading Matrix Symbols Broadband Microstrip-to-Coplanar Strip Double-Y Balun A Topographical Lidar System for Terrain-Relative Navigation Programmable Low-Voltage Circuit Breaker and Tester Electronic Switch Arrays for Managing Microbattery Arrays Topics covered include: Lower-Dark-Current, Higher-Blue-Response CMOS Imagers; Fabricating Large-Area Sheets of Single-Layer Graphene by CVD; Support for Diagnosis of Custom Computer Hardware; Providing Goal-Based Autonomy for Commanding a Spacecraft; Dynamic Method for Identifying Collected Sample Mass; Optimal Planning and Problem-Solving; Attitude-Control Algorithm for Minimizing Maneuver Execution Errors; Grants Document-Generation System; Heat-Storage Modules Containing LiNO3 3H2O and Graphite Foam; Precipitation-Strengthened, High-Temperature, High-Force Shape Memory Alloys; Improved Relief Valve Would Be Less Susceptible to Failure; Safety Modification of Cam-and-Groove Hose Coupling; Using Composite Materials in a Cryogenic Pump; Using Electronic Noses to Detect Tumors During Neurosurgery; Producing Newborn Synchronous Mammalian Cells; Smaller, Lower-Power Fast-Neutron Scintillation Detectors; Rotationally Vibrating Electric-Field Mill; Estimating Hardness from the USDC Tool-Bit Temperature Rise; Particle-Charge Spectrometer; Automated Production of Movies on a Cluster of Computers; FIDO-Class Development Rover; and Tone-Based Command of Deep Space Probes Using Ground Antennas

    2011 Annual Report of the Graduate School of Engineering and Management, Air Force Institute of Technology

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    The Graduate School\u27s Annual Report highlights research focus areas, new academic programs, faculty accomplishments and news, and provides top-level sponsor-funded research data and information

    Air Force Institute of Technology Research Report 2012

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    This report summarizes the research activities of the Air Force Institute of Technology’s Graduate School of Engineering and Management. It describes research interests and faculty expertise; lists student theses/dissertations; identifies research sponsors and contributions; and outlines the procedures for contacting the school. Included in the report are: faculty publications, conference presentations, consultations, and funded research projects. Research was conducted in the areas of Aeronautical and Astronautical Engineering, Electrical Engineering and Electro-Optics, Computer Engineering and Computer Science, Systems and Engineering Management, Operational Sciences, Mathematics, Statistics and Engineering Physics

    NASA Tech Briefs, March 2013

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    Topics covered include: Remote Data Access with IDL Data Compression Algorithm Architecture for Large Depth-of-Field Particle Image Velocimeters Vectorized Rebinning Algorithm for Fast Data Down-Sampling Display Provides Pilots with Real-Time Sonic-Boom Information Onboard Algorithms for Data Prioritization and Summarization of Aerial Imagery Monitoring and Acquisition Real-time System (MARS) Analog Signal Correlating Using an Analog-Based Signal Conditioning Front End Micro-Textured Black Silicon Wick for Silicon Heat Pipe Array Robust Multivariable Optimization and Performance Simulation for ASIC Design; Castable Amorphous Metal Mirrors and Mirror Assemblies; Sandwich Core Heat-Pipe Radiator for Power and Propulsion Systems; Apparatus for Pumping a Fluid; Cobra Fiber-Optic Positioner Upgrade; Improved Wide Operating Temperature Range of Li-Ion Cells; Non-Toxic, Non-Flammable, -80 C Phase Change Materials; Soft-Bake Purification of SWCNTs Produced by Pulsed Laser Vaporization; Improved Cell Culture Method for Growing Contracting Skeletal Muscle Models; Hand-Based Biometric Analysis; The Next Generation of Cold Immersion Dry Suit Design Evolution for Hypothermia Prevention; Integrated Lunar Information Architecture for Decision Support Version 3.0 (ILIADS 3.0); Relay Forward-Link File Management Services (MaROS Phase 2); Two Mechanisms to Avoid Control Conflicts Resulting from Uncoordinated Intent; XTCE GOVSAT Tool Suite 1.0; Determining Temperature Differential to Prevent Hardware Cross-Contamination in a Vacuum Chamber; SequenceL: Automated Parallel Algorithms Derived from CSP-NT Computational Laws; Remote Data Exploration with the Interactive Data Language (IDL); Mixture-Tuned, Clutter Matched Filter for Remote Detection of Subpixel Spectral Signals; Partitioned-Interval Quantum Optical Communications Receiver; and Practical UAV Optical Sensor Bench with Minimal Adjustability

    Research & Technology Report Goddard Space Flight Center

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    The main theme of this edition of the annual Research and Technology Report is Mission Operations and Data Systems. Shifting from centralized to distributed mission operations, and from human interactive operations to highly automated operations is reported. The following aspects are addressed: Mission planning and operations; TDRSS, Positioning Systems, and orbit determination; hardware and software associated with Ground System and Networks; data processing and analysis; and World Wide Web. Flight projects are described along with the achievements in space sciences and earth sciences. Spacecraft subsystems, cryogenic developments, and new tools and capabilities are also discussed

    Research and Technology Report. Goddard Space Flight Center

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    This issue of Goddard Space Flight Center's annual report highlights the importance of mission operations and data systems covering mission planning and operations; TDRSS, positioning systems, and orbit determination; ground system and networks, hardware and software; data processing and analysis; and World Wide Web use. The report also includes flight projects, space sciences, Earth system science, and engineering and materials
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