3 resultados para 1259

em AMS Tesi di Dottorato - Alm@DL - Università di Bologna


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A single picture provides a largely incomplete representation of the scene one is looking at. Usually it reproduces only a limited spatial portion of the scene according to the standpoint and the viewing angle, besides it contains only instantaneous information. Thus very little can be understood on the geometrical structure of the scene, the position and orientation of the observer with respect to it remaining also hard to guess. When multiple views, taken from different positions in space and time, observe the same scene, then a much deeper knowledge is potentially achievable. Understanding inter-views relations enables construction of a collective representation by fusing the information contained in every single image. Visual reconstruction methods confront with the formidable, and still unanswered, challenge of delivering a comprehensive representation of structure, motion and appearance of a scene from visual information. Multi-view visual reconstruction deals with the inference of relations among multiple views and the exploitation of revealed connections to attain the best possible representation. This thesis investigates novel methods and applications in the field of visual reconstruction from multiple views. Three main threads of research have been pursued: dense geometric reconstruction, camera pose reconstruction, sparse geometric reconstruction of deformable surfaces. Dense geometric reconstruction aims at delivering the appearance of a scene at every single point. The construction of a large panoramic image from a set of traditional pictures has been extensively studied in the context of image mosaicing techniques. An original algorithm for sequential registration suitable for real-time applications has been conceived. The integration of the algorithm into a visual surveillance system has lead to robust and efficient motion detection with Pan-Tilt-Zoom cameras. Moreover, an evaluation methodology for quantitatively assessing and comparing image mosaicing algorithms has been devised and made available to the community. Camera pose reconstruction deals with the recovery of the camera trajectory across an image sequence. A novel mosaic-based pose reconstruction algorithm has been conceived that exploit image-mosaics and traditional pose estimation algorithms to deliver more accurate estimates. An innovative markerless vision-based human-machine interface has also been proposed, so as to allow a user to interact with a gaming applications by moving a hand held consumer grade camera in unstructured environments. Finally, sparse geometric reconstruction refers to the computation of the coarse geometry of an object at few preset points. In this thesis, an innovative shape reconstruction algorithm for deformable objects has been designed. A cooperation with the Solar Impulse project allowed to deploy the algorithm in a very challenging real-world scenario, i.e. the accurate measurements of airplane wings deformations.

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Many energetic and environmental evaluations need appropriate meteorological data, as input to analysis and prevision softwares. In Italy there aren't adeguate meteorological data because, in many cases, they are incomplete, incorrect and also very expensive for a long-term analysis (that needs multi-year data sets). A possible solution to this problem is the use of a Typical Meteorological Year (TRY), generated for specific applications. Nowadays the TRYs have been created, using statistical criteria, just for the analysis of solar energy systems and for predicting the thermal performance of buildings, applying it also to the study of photovoltaic plants (PV), though not specifically created for this type of application. The present research has defined the methodology for the creation of TRYs for different applications. In particular TRYs for environmental and wind plant analysis have been created. This is the innovative aspect of this research, never explored before. In additions, the methodology of the generation for the PV TRYs has been improved. The results are very good and the TRYs generated for these applications are adeguate to characterize the climatic condition of the place over a long period and can be used for energetic and environmental studies.

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Il trigono della vescica urinaria (UBT) è un'area limitata attraverso la quale penetrano nella vescica la maggior parte dei vasi e fibre e in cui le fibre nervose e neuroni intramurali sono più concentrati. Mediante l’utilizzo combinato di un tracciante retrogrado(FB) e dell’immunoistochimica sono stati valutati il fenotipo e l’area del soma dei neuroni dei gangli spinali (DRG), dei neuroni post-gangliari, il fenotipo dei gangli della catena simpatica (STG) e i gangli mesenterici caudali (CMG) innervanti l’UBT. - Caratterizzazione dei neuroni dei DRG con: peptide correlato al gene della calcitonina (CGRP)(30±3%, 29±3%, rispettivamente), sostanza P(SP)(26±8%, 27±12%), ossido nitrico sintasi neuronale (nNOS)(21±4%; 26±7%), neurofilamento 200kDa (NF200)(75±14%, 81±7% ) , transient receptor potential vanilloid1 (TRPV1)(48±13%, 43±6%) e isolectina-B4-positivi (IB4) (56±6%;43±10%). I neuroni sensoriali, distribuiti da L2 a Ca1 (DRG), hanno presentato una localizzazione segmentale, mostrando maggior densità nei DRG L4-L5 e S2-S4. I neuroni sensoriali lombari sono risultati significativamente più grandi di quelle sacrali (1.112±624μm2 vs716±421μm2). Complessivamente, questi dati indicano che le vie lombari e sacrali probabilmente svolgono ruoli diversi nella trasmissione sensitiva del trigono della vescica urinaria. -I neuroni FB+ della STG e dei CMG sono risultati immunoreattivi per la tirosina idrossilasi (TH)(66±10,1%, 53±8,2%, rispettivamente), la dopamina beta-idrossilasi (DβH)(62±6,2%, 52±6,2%), neuropeptideY (NPY)(59±8%; 66±7%), CGRP(24±3%, 22±3%), SP(22±2%; 38±8%), polipeptide intestinale vasoattivo (VIP)(19±2%; 35±4%), nNOS(15±2%; 33±8%), trasportatore vescicolare dell'acetilcolina (VAChT)(15±2%; 35±5%), leu-encefalina (LENK)(14±7%; 26±9%), e somatostatina (SOM)(12±3%;32±7%).Il numero medio di neuroni FB+ (1845,1±259,3) era nella STG in L1-S3, con i pirenofori più piccoli (465,6±82.7μm2). Un gran numero (4287,5±1450,6) di neuroni FB+ di piccole dimensioni (476,1±103,9μm2) sono stati localizzati lungo il margine dei CMG. Il maggior numero (4793,3±1990,8) di neuroni FB + è stato osservato nel plesso pelvico, dove i neuroni marcati erano raggruppati in micro-gangli e con pirenoforo ancora più piccolo (374,9±85,4 μm2).