Exploració per tema "X-Rays"

Ara es mostren els items 1-20 de 45

    • A comparison of contrast enhancement methods for 2D radiographic images: Applied to patient positioning in proton therapy 

      Nespereira González, Alejandro (Universitat Politècnica de Catalunya, 2015-05-08)
      Projecte/Treball Final de Carrera
      Accés obert
      Realitzat a/amb:   Université Catholique de Louvain
      Different methods for radiographic image contrast enhancement are studied, implemented and compared. The efficiency of the techniques in improving image contrast is then evaluated both on a subjective evaluation from ...

    • Accretion geometry in the hard state of the black hole X-ray binary MAXI J1820+070 

      Zdziarski, Andrzej A.; Dzielak, Marta A.; Marco, Barbara de (2021-03-01)
      Article
      Accés obert
      We study X-ray spectra from the outburst rise of the accreting black hole binary MAXI J1820+070. We find that models having the disk inclinations within those of either the binary or the jet imply significant changes of ...

    • Air kerma to H-P(3) conversion coefficients for IEC 61267 RQR X-RAY radiation qualities: application to dose monitoring of the lens of the eye in medical diagnostics 

      Principi, Sara; Guardiola Salmerón, Consuelo; Duch Guillen, María Amor; Ginjaume Egido, Mercè (2016-09-01)
      Article
      Accés obert
      Recent studies highlight the fact that the new eye lens dose limit can be exceeded in interventional radiology procedures and that eye lens monitoring could be required for these workers. The recommended operational quantity ...

    • Anna Bertha Ludwig, contigo empezó todo... 

      Salán Ballesteros, Maria Núria (2023)
      Article
      Accés obert
      Història de la primera radiografia, amb descripció de la veritable protagonista, Anna Bertha Ludwig, que no consta als llibres d'història ni de ciència, però que era la propietària de la mà que va mostrar-se en aquella imatge

    • Attosecond state-resolved carrier motion in quantum materials probed by soft x-ray XANES 

      Buades, Bárbara; Picón, Antonio; Berger, Emma; León, Iker; Palo, Nicola di; Cousin, Seth L.; Cocchi, Caterina; Pellegrin, Eric; Herrero Martin, Javier; Mañas-Valero, Samuel; Coronado, Eugenio; Danz, Thomas; Draxl, Claudia; Uemoto, Mitsuharu; Yabana, Kazuhiro; Schultze, Martin; Wall, Simon; Zürch, Michael; Biegert, Jens (AIP, 2021-03-10)
      Article
      Accés obert
      Recent developments in attosecond technology led to table-top x-ray spectroscopy in the soft x-ray range, thus uniting the element- and state-specificity of core-level x-ray absorption spectroscopy with the time resolution ...

    • Automatic localisation and segmentation of the Left Ventricle in Cardiac Ultrasound Images 

      Puyol Anton, Esther (Universitat Politècnica de Catalunya, 2014-09-12)
      Projecte/Treball Final de Carrera
      Accés obert
      Realitzat a/amb:   École nationale supérieure des télécommunications de Bretagne
      [ANGLÈS] Echocardiography is a common non-invasive diagnostic image modality that uses ultrasound to capture the structure and the function of the heart. During the last years there has been a growing need to automate the ...

    • Caracterización de haces de rayos X de baja energía 

      Casanovas Alegre, Ramon (Universitat Politècnica de Catalunya / Universitat de Barcelona, 2008-07-07)
      Projecte Final de Màster Oficial
      Accés obert
      El proyecto desarrollado describe el procedimiento seguido para caracterizar un conjunto de haces de rayos X para la calibración de equipos de medida de la radiación utilizados en el ámbito del radiodiagnóstico médico. La ...

    • Coherent amplification of attosecond light pulses in the water-window spectral region 

      Serrat Jurado, Carles; Roca, David; Seres, Jozsef (2015-02-23)
      Article
      Accés obert
      We present a theoretical study on coherent extreme ultraviolet (XUV) attosecond pulse amplification mediated by nonlinear parametric enhanced forward scattering occurring in the interaction of a strong femtosecond infrared ...

    • Constraining the origin of the short timescales X-ray variability of the Seyfert galaxy NGC 7469 

      Núñez Arilla, Carlos (Universitat Politècnica de Catalunya, 2020-06)
      Treball Final de Grau
      Accés obert
      Realitzat a/amb:   Nicolaus Copernicus Astronomical Center
      This bachelor thesis is a small part of a much larger project related to the study of the X-ray properties of the active galactic nucleus (AGN) NGC 7469. In this report I will focus on the analysis of the short-timescales ...

    • Deep Learning on medical images image captioning on X-rays 

      Schwall, Immanuel Parzival (Universitat Politècnica de Catalunya, 2017-02-28)
      Projecte Final de Màster Oficial
      Accés restringit per acord de confidencialitat
      Realitzat a/amb:   Eidgenössische Technische Hochschule Zürich

    • Dense matter with eXTP 

      Yu, WenFei; Poutanen, Juri; Zhang, Shu; Linares Alegret, Manuel (2019-02-01)
      Article
      Accés obert
      In this White Paper we present the potential of the Enhanced X-ray Timing and Polarimetry (eXTP) mission for determining the nature of dense matter; neutron star cores host an extreme density regime which cannot be replicated ...

    • Detection of an unidentified soft X-ray emission feature in NGC 5548 

      Gu, Liyi; Mao, Junjie; Kaastra, J.S.; Mehdipour, M.; Pinto, Ciro; Grafton Waters, Sam; Bianchi, Stefano; Landt, Hermine; Branduardi Raymont, Graziella; Costantini, Elisa; Ebrero, Jacob; Petrucci, P.O.; Behar, Ehud; Di Gesu, Laura; Marco, Barbara de (EDP Sciences, 2022-09-01)
      Article
      Accés obert
      Context. NGC 5548 is an X-ray bright Seyfert 1 active galaxy. It exhibits a variety of spectroscopic features in the soft X-ray band, in particular including the absorption by the active galactic nucleus (AGN) outflows of ...

    • Débruitage et sup er-résolution des images rayons X 

      García Hernando, Guillermo Joaquín (Universitat Politècnica de Catalunya, 2013-05-16)
      Projecte/Treball Final de Carrera
      Accés restringit per decisió de l'autor
      Realitzat a/amb:   École nationale supérieure des télécommunications
      [ANGLÈS] This document contains the Master thesis pursued in the R&D department of Smiths Detection (Vitry-sur-Seine, France) between July 2012 and January 2013 in order to obtain the degrees M.S. in Telecommunications ...

    • Dynamics of the vitreous state 

      Ruiz de la Cuesta Castaño, Paula (Universitat Politècnica de Catalunya, 2021-07-13)
      Treball Final de Grau
      Accés obert
      Metallic glasses have a disordered structure, out of equilibrium, which does not stop changing towards a more stable state. This physical aging process, driven by structural relaxation, has been investigated for some time ...

    • Extreme-ultraviolet coherent pulse amplification in argon 

      Serrat Jurado, Carles; Seres, Jozsef; Seres, Enikoe; Namba, Shinichi (2019-06-25)
      Article
      Accés obert
      The amplification of ultrashort extreme-ultraviolet (XUV) pulses in argon in high-order harmonic generation processes is studied by using the time-dependent Schrödinger equation in the spin-free one-active-electron and ...

    • Imaging soil-root interaction using X-ray micro-computed tomography 

      Lascurain i Feliu, Tomàs (Universitat Politècnica de Catalunya, 2020-06-01)
      Treball Final de Grau
      Accés obert
      The interaction between plant roots and soil is extremely relevant and difficult to study as the soil is an opaque and heterogeneous environment. The study of soil physical characteristics as a driver of root development ...

    • In Situ X-Ray Photoelectron Spectroscopy Gas-Solid Carbonation of Ultramafic Rocks: Implications for Carbon Capture and Storage 

      Zhao, Rong (Universitat Politècnica de Catalunya, 2012-07)
      Projecte Final de Màster Oficial
      Accés obert
      [ANGLÈS] With the increasing carbon dioxide emission in the atmosphere, there has been an interesting interest in CCS (Carbon Capture and Storage). Mineral carbonation was considered as a better option for storage ...

    • Localized Core Four-Wave Mixing Buildup in the X-ray Spectrum of Chemical Species 

      Serrat Jurado, Carles (2021-01-20)
      Article
      Accés obert
      Using the Kohn–Sham density functional theory, we numerically study the four-wave mixing response of a carbon atom model system exposed to a train of femtosecond two color ω–3ω random phase coherent X-ray pulses near the ...

    • Mass-loss and composition of wind ejecta in type I X-ray bursts 

      Herrera, Yago; Sala Cladellas, Glòria; José Pont, Jordi (EDP Sciences, 2023-10-17)
      Article
      Accés obert
      Context. X-Ray bursts (XRBs) are powerful thermonuclear events on the surface of accreting neutron stars (NSs) where nucleosynthesis of intermediate-mass elements occurs. The high surface gravity of an NS prevents the ...

    • Material characterization and Monte Carlo simulation of lead and non-lead X-Ray shielding materials 

      Aral, Nebahat; Duch Guillen, María Amor; Ardanuy Raso, Mònica (2020-04-16)
      Article
      Accés obert
      In this paper, the compositions of commercial lead and non-lead X-ray protective materials were investigated by material analysis methods as FTIR-ATR, SEM/EDS, and density measurement to estimate the content of the structures, ...