Search results for " Stereo"

Real time UAV altitude, attitude and motion estimation from hybrid stereovision

2012

International audience; Knowledge of altitude, attitude and motion is essential for an Unmanned Aerial Vehicle during crit- ical maneuvers such as landing and take-off. In this paper we present a hybrid stereoscopic rig composed of a fisheye and a perspective camera for vision-based navigation. In contrast to classical stereoscopic systems based on feature matching, we propose methods which avoid matching between hybrid views. A plane-sweeping approach is proposed for estimating altitude and de- tecting the ground plane. Rotation and translation are then estimated by decoupling: the fisheye camera con- tributes to evaluating attitude, while the perspective camera contributes to estimating t…

Intermolecular oxidative dehydrogenative 3,3′-coupling of benzo[b]furans and benzo[b]thiophenes promoted by DDQ/H+: total synthesis of shandougenine B

2016

With an excess of a strong acid, 2,3-dichloro-5,6-dicyano-1,4-quinone (DDQ) is shown to promote metal-free intermolecular oxidative dehydrogenative (ODH) 3,3'-coupling of 2-aryl-benzo[b]furans and 2-aryl-benzo[b]thiophenes up to 92% yield as demonstrated with 9 substrates. Based on the analysis of oxidation potentials and molecular orbitals combined with EPR, NMR and UV-Vis observations, the studied reaction is initiated by a DDQ-substrate charge transfer complex and presumably proceeds via oxidation of the substrate into an electrophilic radical cation that further reacts with another molecule of a neutral substrate. The coupling reactivity can easily be predicted from the oxidation potent…

Voice and identity: a contrastive study of identity perception in voice

2009

En mi tesis doctoral he estudiado qué elementos suprasegmentales de la voz se combinan a nivel prosódico para transmitir información sobre nuestra identidad (origen, personalidad, emociones.). En la parte teórica se define el concepto de identidad, llegando a la conclusión de que identidad es un término relacional que construye un paralelismo entre dos campos, el de la individualidad y el de la colectividad. En el marco teórico se tratan distintas teorías como el constructivismo radical y el experiencialismo radical para comprender cómo la percepción, la estereotipación y la categorización de la voz son actores indispensables a la hora de utilizar la voz o escuchar otras voces. En la parte …

Intraoperative imaging findings in transcranial MR imaging-guided focused ultrasound treatment at 1.5T may accurately detect typical lesional finding…

2020

To assess the intraoperative neuroimaging findings in patients treated with transcranial MR-guided focused ultrasound (tcMRgFUS) thalamotomy using 1.5T equipment in comparison with the 48-h follow-up.Fifty prospectively enrolled patients undergoing unilateral tcMRgFUS thalamotomy for either medication-refractory essential tremor (n = 39) or Parkinson tremor (n = 11) were included. Two radiologists evaluated the presence and size of concentric lesional zones (zone I, zone II, and zone III) on 2D T2-weighted sequences acquired intraoperatively after the last high-energy sonication and at 48 h. Sonication parameters including number of sonications, delivered energy, and treatment temperatures …

Hippocampal dose during Linac-based stereotactic radiotherapy for brain metastases: An observational study

2017

Abstract Introduction Aim of the present study is to evaluate homolateral and contralateral hippocampus (H-H, C-H, respectively) dose during Fractionated Stereotactic Radiotherapy (FSRT) or Radiosurgery (SRS) for brain metastases (BM). Materials & methods Patients with BM   3 months, were considered for SRS/FSRT (total dose 15–30 Gy, 1–5 fractions). For each BM, a Flattening Filter Free (FFF) Volumetric Modulated Arc Therapy (VMAT) plan was generated with one or two arcs. Hippocampi were not considered during optimizations phase and were contoured and evaluated retrospectively in terms of dose: the Dmedian, Dmean, D0.1cc and the V1Gy, V2Gy, V5Gy and V10Gy were analyzed. Results From April 2…

ASSESSMENT OF BRAIN METASTASES VOLUME CONTROL DURING STEREOTACTIC RADIOSURGERY BY LONGITUDINAL REGION GROWTH MR IMAGE SEGMENTATION ANALYSIS

2015

1-Benz­yloxy-1H-benzotriazole

2012

In the title compound, C13H11N3O, the dihedral angle between the benzotriazole ring system [maximum deviation = 0.027 (16) Å] and the benzene ring is 10.28 (9)°. The C—C—O—N bond adopts an anti conformation [torsion angle = −177.11 (16)°]. In the crystal, the molecules interact via weak C—H...π interactions and aromatic π–π stacking [centroid-to-centroid distance = 3.731 (12) Å].

Ring transformation of furfural into an unusual bicyclic system: Characterisation and dynamic stereochemistry of 6,7-diethoxycarbonyl-6,7-diaza-8-oxa…

1997

Abstract 2-Formylthiophene and 3-formylindole react with diethyl azodicarboxylate to give simple products derived from reactions on the formyl group whereas 2-formylfuran reacts to give the unexpected bicyclic title compound. 1 H and 13 C NMR studies indicate that this compound undergoes a series of three dynamic conformational changes over the temperature range 50 to −90°C which are ascribed to slow rotation about the exocyclic carbamate bonds and hindered bridge inversion.

Hybrid Methods for Robust Irradiance Analysis and 3-D Shape Reconstruction from Images

1994

The analysis of the differential structure of images is an interesting task in machine vision, among other reasons because it can provide relevant featural representation of images, suited for higher level information processing task like geometry reconstruction and object recognition. The importance of invariants of the field of isophotae on lambertian surfaces in shape perception by means of chiaroscuro is discussed in (Koenderink and Van Doom, 1980). In their approach to shape from shading, (Breton et al, 1992) represent the shading of the image by means of its shading flow field, i.e. by the first order differential structure of the image expressed as the isoluminance direction and grad…

Il Castello Maniace di Siracusa. Stereotomia e tecniche costruttive nell’architettura del Mediterraneo

2011

L’enigma del castello Maniace di Siracusa, realizzato nella prima metà del XIII secolo per volontà dell’imperatore Federico II, ruota intorno all’immensa sala colonnare, alla sua funzione e ai criteri costruttivi adottati per edificarla. L’autrice ha avuto l’opportunità di studiare capillarmente la fabbrica, assumendo una conoscenza materica diretta, grazie alla lunga frequentazione, resa possibile dal cantiere di restauro che ha recentemente restituito il “monumento” alla fruizione pubblica. Queste informazioni sono state utilizzate per verificare le diverse letture e ipotesi sinora formulate e l’indagine procede a partire dalla densa serie di quesiti inevasi. Di fronte a una architettura …