Search results for "COMPRESSION"
showing 10 items of 774 documents
Review of Particle Physics
2020
The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 2,143 new measurements from 709 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as supersymmetric particles, heavy bosons, axions, dark photons, etc. Particle properties and search limits are listed in Summary Tables. We give numerous tables, figures, formulae, and reviews of topics such as Higgs Boson Physics, Supersymmetry, Grand Unified Theories, Neutrino Mixing, Dark Energy, Dark Matter, Cosmology, Particle Detectors, Colliders, …
Space-Frequency Quantization for Image Compression With Directionlets
2007
The standard separable 2-D wavelet transform (WT) has recently achieved a great success in image processing because it provides a sparse representation of smooth images. However, it fails to efficiently capture 1-D discontinuities, like edges or contours. These features, being elongated and characterized by geometrical regularity along different directions, intersect and generate many large magnitude wavelet coefficients. Since contours are very important elements in the visual perception of images, to provide a good visual quality of compressed images, it is fundamental to preserve good reconstruction of these directional features. In our previous work, we proposed a construction of critic…
Involucri Traslucidi in Vetromattone: nuove tecniche di assemblaggio a secco ed incremento prestazionale del prodotto per la riduzione del valore di …
2010
Nel corso del Novecento l’impiego dei diffusori di vetro per la realizzazione di elementi tecnici traslucidi in grado di captare la luce naturale ha subito alterne vicende. Dopo un periodo di intenso utilizzo a cavallo del XIX e XX secolo e dopo la realizzazione, in Europa, negli anni a cavallo tra le due guerre, di alcuni edifici divenuti emblematici del Movimento Moderno, l’impiego di questo prodotto “innovativo” per l’epoca, venne progressivamente “relegato” alle parti più nascoste degli edifici per la “pragmatica” risoluzione di problematiche legate, ad es., alla presenza di particolari vincoli urbanistici senza che, quindi, ne venissero ulteriormente indagate le potenzialità espressive…
All polarization-maintaining assively mode-locked yb-doped fiber laser : pulse compression using an anomalous polarization-maintaining photonic cryst…
2019
We report the generation of short pulses at 1 μm using an all-polarization-maintaining (PM) fiber configuration. The pulses are provided by an all normal-dispersion Fabry-Perot Yb-doped cavity and are compressed with an anomalous polarization-maintaining photonic crystal fiber (PM PCF). Opposed to standard configurations; here the filtering action is solely performed by the finite bandwidth of the gain medium. The laser generates 8 ps width sech 2 profile pulses at 1046.8 nm with a −10 dB bandwidth of 5.9 nm. After compression using the PM PCF, pulses with an FWHM of 3 ps were obtained, limited by the actual value of the available anomalous dispersion. We also report the changes in the outp…
Yielding of a quartz sand from saturated to dry state
2020
The paper presents the results of an experimental work where we analyse the behaviour of an unsaturated quartz sand in a wide range of degree of saturation (from saturated to dry state). The possibility of anticipating the hydro-mechanical behaviour of the soils when they approach the dry state is fundamental in many areas. An extensive experimental program, including controlled-suction and constant water content oedometric tests, was carried out to deeply analyse the water retention behaviour and the relationship between the yield stress and suction (Loading-Collapse curve). All elasto-plastic models provide a monotonically increase of the yield stress with suction. This assumption implies…
CT imaging findings of abdominopelvic vascular compression syndromes: what the radiologist needs to know.
2020
AbstractAbdominopelvic vascular compression syndromes include a variety of uncommon conditions characterized by either extrinsic compression of blood vessels by adjacent anatomical structures (i.e., median arcuate ligament syndrome, nutcracker syndrome, May-Thurner syndrome) or compression of hollow viscera by adjacent vessels (i.e., superior mesenteric artery syndrome, ureteropelvic junction obstruction, ureteral vascular compression syndromes, portal biliopathy). These syndromes can be unexpectedly diagnosed even in asymptomatic patients and the predisposing anatomic conditions can be incidentally discovered on imaging examinations performed for other indications, or they can manifest wit…
Sistemas de compresión. Análisis de presiones. Estudio de diferentes procedimientos metodológicos.
2014
Objetivo: Los sistemas de compresión son sistemas que a través de sus componentes y su correcta utilización son capaces de conseguir una serie de objetivos biomecánicos en una zona concreta anatómica, previamente traumatizada o como prevención de un proceso traumático. El objetivo principal de este estudio es contrastar los diferentes estudios de investigación encontrados en las bases de datos para poder conocer qué sistemas de compresión son más efectivos en la clínica. Material y método: Se realiza una revisión bibliográfica de tipo descriptiva por las diferentes bases de datos, como son Pubmed, Cochrane, Cuiden y Dialnet, con la finalidad de actualizar la información existente sobre los …
Experimental study on the effects of physical training on the defibrillation threshold
2011
Background: Chest compression artifacts during cardiopulmonary resuscitation (CPR) deteriorate the rhythm diagnosis of automated external defibrillators (AED). Cardiopulmonary resuscitation must therefore be interrupted for a reliable shock/no-shock decision. However, these hands-off intervals adversely affect the defibrillation success, and, in addition, pauses in chest compressions compromise circulation. An accurate diagnosis of the rhythmwhile performing CPR is therefore needed to minimize these hands-off intervals. Methods: The characteristics of the CPR artifact are very variable, and the artifact presents an important spectral overlap with human cardiac arrest rhythms. Consequently, …
An unusual internal carotid artery compression as a possible cause of Eagle syndrome – A novel hypothesis and an innovative surgical technique
2019
Background: Eagle syndrome (ES) is a rare symptomatic condition generally caused by an elongated styloid process (SP) or calcification of the stylohyoid complex. On the diagnosis is made, its treatment remains subjective since the indications for surgical intervention are still not standardized. Although styloidectomy is the surgical treatment of choice, no consensus exists regarding the transcervical or/and transoral route. Here, we report our experience in a patient with bilateral internal carotid artery (ICA) dissection caused by ES, who underwent innovative surgical technique. Case Description: A 53-year-old man, with the right-sided middle cerebral artery acute stroke, underwent compu…
Focus on functional delayed central sleep apnea following cervical laminectomy. An example of respiratory dysfunction in restorative neurosurgical pr…
2017
In sleep-related breathing disorders, sleep apnea is a clinical symptom that can be categorized as obstructive sleep apnea (OSA) or mixed apnea by analysis using poly-somnography. The occurrence of delayed central sleep apnea (CSA) is an extremely rare complication of cervical laminectomy for spondylotic myelopathy. So far only three studies concerning such an event have been reported in the literature. Naim-ur-Rahman, in 1994, reported a case of postoperative CSA following C3-C6 laminectomy, and Visocchi and colleagues, in 2014, in two studies, stressed the lack of association with any other neurological sign of spinal cord damage. No definitive mechanism has been recognized so far for del…