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Related papers: Segmented coronagraph design and analysis (SCDA): …

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Cardiac MR image segmentation is essential for the morphological and functional analysis of the heart. Inspired by how experienced clinicians assess the cardiac morphology and function across multiple standard views (i.e. long- and…

Image and Video Processing · Electrical Eng. & Systems 2019-12-18 Chen Chen , Carlo Biffi , Giacomo Tarroni , Steffen Petersen , Wenjia Bai , Daniel Rueckert

Using 2 aspheric mirrors, it is possible to apodize a telescope beam without losing light or angular resolution: the output beam is produced by ``remapping'' the entrance beam to produce the desired light intensity distribution in a new…

The Roman Space Telescope will have the first advanced coronagraph in space, with deformable mirrors for wavefront control, low-order wavefront sensing and maintenance, and a photon-counting detector. It is expected to be able to detect and…

The world's first ever ''adaptive stellar coronagraph'' facility will be the PLACID instrument, installed on Turkey's new national observatory 4-m DAG telescope. PLACID incorporates a customized spatial light modulator (SLM) acting as a…

Instrumentation and Methods for Astrophysics · Physics 2024-08-21 Ruben Tandon , Liurong Lin , Axel Potier , Laurent Jolissaint , Audrey Baur , Derya Öztürk Çetni , Jonas G. Kühn

Heart is one of the vital organs of human body. A minor dysfunction of heart even for a short time interval can be fatal, therefore, efficient monitoring of its physiological state is essential for the patients with cardiovascular diseases.…

Image and Video Processing · Electrical Eng. & Systems 2019-11-22 Shakeel Muhammad Ibrahim , Muhammad Sohail Ibrahim , Muhammad Usman , Imran Naseem , Muhammad Moinuddin

Non-invasive detection of cardiovascular disorders from radiology scans requires quantitative image analysis of the heart and its substructures. There are well-established measurements that radiologists use for diseases assessment such as…

Machine Learning · Statistics 2017-08-04 Aliasghar Mortazi , Jeremy Burt , Ulas Bagci

Echocardiogram video segmentation plays an important role in cardiac disease diagnosis. This paper studies the unsupervised domain adaption (UDA) for echocardiogram video segmentation, where the goal is to generalize the model trained on…

Computer Vision and Pattern Recognition · Computer Science 2023-09-21 Jiewen Yang , Xinpeng Ding , Ziyang Zheng , Xiaowei Xu , Xiaomeng Li

Segmented aperture telescopes require an alignment procedure with successive steps from coarse alignment to monitoring process in order to provide very high optical quality images for stringent science operations such as exoplanet imaging.…

Instrumentation and Methods for Astrophysics · Physics 2017-04-20 Pierre Janin-Potiron , Mamadou N'Diaye , Patrice Martinez , Arthur Vigan , Kjetil Dohlen , Marcel Carbillet

Second-generation exoplanet imagers using extreme adaptive optics and coronagraphy have demonstrated their great potential for studying close circumstellar environments and for detecting new companions and helping to understand their…

Instrumentation and Methods for Astrophysics · Physics 2019-08-28 A. Vigan , M. N'Diaye , K. Dohlen , J. -F. Sauvage , J. Milli , G. Zins , C. Petit , Z. Wahhaj , F. Cantalloube , A. Caillat , A. Costille , J. Le Merrer , A. Carlotti , J. -L. Beuzit , D. Mouillet

External occulters, otherwise known as starshades, have been proposed as a solution to one of the highest priority yet technically vexing problems facing astrophysics - the direct imaging and characterization of terrestrial planets around…

Instrumentation and Methods for Astrophysics · Physics 2015-05-28 Webster Cash

We propose a new approach for high-contrast imaging at the diffraction limit using segmented telescopes in a modest observation bandwidth. This concept, named "spectroscopic fourth-order coronagraphy", is based on a fourth-order coronagraph…

Instrumentation and Methods for Astrophysics · Physics 2021-03-17 Taro Matsuo , Satoshi Itoh , Yuji Ikeda

Exoplanet imaging and spectroscopy are now routinely achieved by dedicated instruments on large ground-based observatories (e.g. Gemini/GPI, VLT/SPHERE, or Subaru/SCExAO). In addition to extreme adaptive optics (ExAO) and post-processing…

Instrumentation and Methods for Astrophysics · Physics 2019-03-19 Mamadou N'Diaye , Kevin Fogarty , Rémi Soummer , Alexis Carlotti , Kjetil Dohlen , Johan Mazoyer , Laurent Pueyo , Kathryn St. Laurent , Neil Zimmerman

X-ray coronary angiography (XCA) is used to assess coronary artery disease and provides valuable information on lesion morphology and severity. However, XCA images are 2D and therefore limit visualisation of the vessel. 3D reconstruction of…

Image and Video Processing · Electrical Eng. & Systems 2023-03-01 Kit Mills Bransby , Vincenzo Tufaro , Murat Cap , Greg Slabaugh , Christos Bourantas , Qianni Zhang

We propose a transmission-filter coronagraph for direct imaging of Jupiter-like exoplanets with ground-based telescopes. The coronagraph is based on a transmission filter that consists of finite number of transmission steps. A discrete…

Instrumentation and Methods for Astrophysics · Physics 2015-10-14 Deqing Ren , Jiangpei Dou , Yongtian Zhu

In cardiac magnetic resonance (CMR) imaging, a 3D high-resolution segmentation of the heart is essential for detailed description of its anatomical structures. However, due to the limit of acquisition duration and respiratory/cardiac…

Image and Video Processing · Electrical Eng. & Systems 2021-07-09 Shuo Wang , Chen Qin , Nicolo Savioli , Chen Chen , Declan O'Regan , Stuart Cook , Yike Guo , Daniel Rueckert , Wenjia Bai

Personalized 3D vascular models can aid in a range of diagnostic, prognostic, and treatment-planning tasks relevant to cardiovascular disease management. Deep learning provides a means to obtain such models automatically from image data.…

Image and Video Processing · Electrical Eng. & Systems 2024-08-20 Patryk Rygiel , Dieuwertje Alblas , Christoph Brune , Kak Khee Yeung , Jelmer M. Wolterink

One of the main challenges for the direct imaging of planets around nearby stars is the suppression of the diffracted halo from the primary star. Coronagraphs are angular filters that suppress this diffracted halo. The Apodizing Phase Plate…

Instrumentation and Methods for Astrophysics · Physics 2014-12-03 G. P. P. L. Otten , F. Snik , M. A. Kenworthy , M. N. Miskiewicz , M. J. Escuti

Prevention of secondary brain injury is a core aim of neurocritical care, with Spreading Depolarizations (SDs) recognized as a significant independent cause. SDs are typically monitored through invasive, high-frequency electrocorticography…

Signal Processing · Electrical Eng. & Systems 2025-05-20 Jeanne Boyer-Chammard , Yinzhe Wu , Chenyu Zhang , Sharon Jewell , Anthony Strong , Guang Yang , Martyn Boutelle

We propose a novel multi-stage trans-dimensional architecture for multi-view cardiac image segmentation. Our method exploits the relationship between long-axis (2D) and short-axis (3D) magnetic resonance (MR) images to perform a sequential…

Image and Video Processing · Electrical Eng. & Systems 2024-04-26 Abbas Khan , Muhammad Asad , Martin Benning , Caroline Roney , Gregory Slabaugh

Coronagraphic techniques are required to detect exoplanets with future Extremely Large Telescopes. One concept, the Apodized Pupil Lyot Coronagraph (APLC), is combining an apodizer in the entrance aperture and a Lyot opaque mask in the…

Astrophysics · Physics 2009-11-13 P. Martinez , C. Dorrer , E. Aller Carpentier , M. Kasper , A. Boccaletti , K. Dohlen , N. Yaitskova