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Locardel-Rietzler, Joëlle. "Recherche de nouveaux liants polymères substituts du PEG dans le procédé de granulation par fusion." Montpellier 1, 2000. http://www.theses.fr/2000MON13510.
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Serhal, Karine. "Production et caractérisation d'hybrides cellulaires obtenus par la fusion de cellules dendritiques et cellules de carcinome mammaire T-47D dans un but de vaccination anti-tumorale." Paris 6, 2007. http://www.theses.fr/2007PA066663.
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Dans le contexte de l’immunothérapie anti-tumorale, la fusion des cellules dendritiques (DC) avec les cellules tumorales a pour but d’obtenir des cellules fusionnées capables d’éradiquer les tumeurs établies ou d’empêcher leur développement. Nos objectifs sont : (1) d’optimiser la production de cellules fusionnées et de les caractériser en identifiant les faux positifs, (2) d’étudier leur immuno-phénotype et leur fonctionnalité. Ce travail permet de réduire les facteurs de variabilité du processus de fusion DC/cellules tumorales et d’insister sur la complémentarité des méthodes de caractérisation. Les cellules fusionnées sont capables d’induire une réponse immunitaire et leur fonctionnalité, liée à leur état de maturation, se manifeste par la sécrétion de cytokines et de perforine par les LT activés. Leur phénotype non adhérent et leur capacité à exprimer le gène CCR7 ouvrent la voie à des expériences de migration et d’évaluation de l’activité anti-tumorale chez l’animal.
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Cantin, Oriane. "PEO hot melt extrudates for controlled drug delivery." Thesis, Lille 2, 2016. http://www.theses.fr/2016LIL2S035/document.
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Parmi les procédés de fabrication continue, l’extrusion par fusion à chaud est une technique dont l’intérêt dans le domaine pharmaceutique est grandissant. Ce procédé permet la formation des dispersions solides des substances actives au sein des matrices polymériques ou lipidiques. En fonction de l’excipient et de la substance active, cela peut être largement utilisé pour la conception des systèmes: (i) pour une libération immédiate, (ii) pour une libération modifiée et (iii) pour le masquage de goût. Les systèmes à libération modifiée sont des dispositifs intéressants qui permettent d’améliorer la biodisponibilité de la substance active, son efficacité ainsi que l’observance des patients. En fonction de la nature de l’excipient, différents systèmes avec des mécanismes de libération variés peuvent être produit, notamment des matrices inerte, érodable ou gonflante. Le poly éthylène oxide est un polymère semi- cristallin et hydrophile qui peut être utilisé pour la libération contrôlée. Son point de fusion compris entre 63 et 67 °C le rend adapté pour l’extrusion. Surtout, ses capacités de gonflement permettent d’administrer la substance active de façon contrôlée en fonction du poids moléculaire du poly éthylène oxide. Les objectifs de ce travail sont (i) d’étudier l’impact des paramètres critiques du procédé (température d’extrusion et vitesse des vis d’extrudeuse) sur le profil de libération de la substance active, (ii) de déterminer l’impact des paramètres de formulations (poids moléculaire du poly éthylène oxide, charge et type de la substance active) sur le profil de libération de la substance active et (iii) d’évaluer des formes galéniques solides conçues par le procédé d’extrusion à celui de la compression directe. Il a été montré que la variation de la température d’extrusion et de la vitesse des vis altérait l’apparence de l’extrudat et ainsi la distribution de la substance active au sein de l’extrudat. Il s’est avéré dans notre étude que la libération de la substance active n’était pas particulièrement affectée par ces changements de température et vitesse de vis de l’extrudeuse. De plus, cette étude a permis de fixer les paramètres pour les projets suivants: température 100 °C ; vitesse des vis 30 rpm ; longueur de la forme galénique 1 cm. Des extrudats de poly ethylène oxide contenant 10 % de théophylline et du poly éthylène oxide de 100 à 7000 kDa ont été utilisés dans ce travail. Il a été observé que lorsque le poids moléculaire du poly ethylène oxide augmente de 100 à 600 kDa, la libération en substance active diminue de façon importante alors qu’une augmentation jusqu’à 7000 kDa ne diminue que légèrement la libération. Des études du gonflement ont montré que ce phénomène corrélait aux variations de volume de la partie opaque de l’extrudat (gel non transparent et cœur solide)Among continuous manufacturing processes, hot melt extrusion is a technique with growing interest in the pharmaceutical field. This process enables the formation of solid dispersions of many drugs within a polymeric or lipidic carrier. Hot melt extrusion can be widely used for different issues using the appropriate carrier and drug. Here are the mostly used concepts in pharmaceutical solid dosage forms: (i) immediate release, (ii) modified release and (iii) taste masking. Modified release systems have been taken into account to be very interesting devices for the improvement of drug- bioavailability, drug- efficacy as well as the patient compliance. Various systems with different release mechanisms can be manufactured, depending on the nature of the carrier (inert, erodible, and swelling matrices). Poly ethylene oxide is a semi crystalline and hydrophilic polymer which can be used to control drug delivery. The poly ethylene oxide melting point ranging from 63 to 67 °C makes it suitable for hot melt extrusion. Importantly, the swelling capacities of the hydrophilic poly ethylene oxide matrices are able to deliver drug in a time controlled manner, in respect of the poly ethylene oxide molecular weights. The purposes of this work were (i) to study the impact of critical process parameters (extrusion temperature and screw speed) on the drug release behavior, (ii) to determine the impact of formulation parameters (poly ethylene oxide molecular weight, nature of drug and drug loading) on drug release kinetics, and (iii) to evaluate solid dosage forms prepared by hot melt extrusion versus direct compression. Interestingly, the variation of the extrusion temperature and the screw speed leads to the altering of the extrudate appearance and thus the distribution of drug into the extrudate. However, this changing has not influenced the drug release remarkably. Thus, this study was useful to set the parameters for the following projects (temperature 100 °C; screw speed 30 rpm; dosage form size 1 cm). Poly ethylene oxide hot melt extrudates containing 10 % theophylline and based on 100 - 7,000 kDa poly ethylene oxide are used for this thesis. Importantly, the drug release decreased substantially with the increase of the poly ethylene oxide molecular weight from 100 to 600 kDa. However, further increasing of the molecular weights leads to only a slight decrease in the release rate. Swelling studies have shown that this phenomenon correlated with the change in volume of the opaque part of the extrudates (non-transparent gel and solid core)
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Zheng, Yiran. "CT-PET Image Fusion and PET Image Segmentation for Radiation Therapy." Case Western Reserve University School of Graduate Studies / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=case1283542509.
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Rossi, Michele. "Sensor fusion per la localizzazione indoor in applicazioni context-aware." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/12894/.
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Nel contesto della Realtà Aumentata e della tecnologia Wearable, la richiesta, e soprattutto la necessità, di applicazioni context-aware ha reso il concetto di posizione una informazione estremamente importante. Il presente documento mira a fornire una solida base per la progettazione e realizzazione di un sistema di localizzazione indoor attraverso l'uso di sensori inerziali e di tecniche di filtering, in particolare il filtro di Kalman e le varianti Extended e Unscented per la riduzione degli errori di stima, comparandone le performance.
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Scarponi, Valentina. "Data fusion per un nodo sensore basato su piattaforma inerziale." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
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Lo scopo principale dell’elaborato è descrivere la programmazione del nodo sensore LSM6DSL, dotato di accelerometro e giroscopio, al fine di fornire in uscita dati affidabili riguardo all’inclinazione, sia alle basse che alle alte frequenze. L’accelerometro è infatti in grado di produrre informazioni accurate solo alle basse frequenze, mentre il giroscopio dà misure precise solo alle alte. Unendo le due componenti in modo opportuno, si ottiene il dato cercato, con un buon grado di affidabilità.
Per trovare il giusto algoritmo di fusione, è stato utilizzato il lavoro di Liu et al, nel quale è proposta una soluzione che prevede l’uso di due filtri complementari, uno passa basso e uno passa alto, per elaborare rispettivamente i dati provenienti da accelerometro e giroscopio e poi fonderli insieme.
I filtri sono stati implementati sia come analogici che come digitali. La soluzione teorica prevede l’uso di filtri FIR digitali, intrinsecamente più stabili, ma poiché le due possibilità si sono dimostrate perfettamente sovrapponibili, si è deciso di sfruttare filtri analogici, computazionalmente più facili da realizzare
Si è passati poi alla fase di ottimizzazione, necessaria in vista dell’implementazione del programma direttamente sul nodo sensore. L’algoritmo è stato modificato per far sì che i dati provenienti da accelerometro e giroscopio venissero fusi ed elaborati in porzioni composte da un numero di campioni minore rispetto al totale acquisito, riducendo di molto la complessità di operazioni come la trasformata di Fourier. Per minimizzare l’errore introdotto da tale elaborazione, sono stati ricercati numero di campioni e frequenza di taglio ottimali.
L'algoritmo risultante è stato prima implementato in ambiente Matlab, poi è stato tradotto in linguaggio C, in modo che il programma potesse essere scritto direttamente sul nodo sensore, in grado a questo punto non solo di acquisire i dati, ma anche di elaborarli in modo opportuno, mantenendo una buona versatilità.
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Kuldkepp, Mattias. "Diagnostics for advanced fusion plasma scenarios." Doctoral thesis, Stockholm : Atomic and Molecular Physics, Department of Physics, Royal Institute of Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4221.
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Kim, Ilseo. "Per-exemplar analysis with MFoM fusion learning for multimedia retrieval and recounting." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/52152.
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As a large volume of digital video data becomes available, along with revolutionary advances in multimedia technologies, demand related to efficiently retrieving and recounting multimedia data has grown. However, the inherent complexity in representing and recognizing multimedia data, especially for large-scale and unconstrained consumer videos, poses significant challenges. In particular, the following challenges are major concerns in the proposed research.
One challenge is that consumer-video data (e.g., videos on YouTube) are mostly unstructured; therefore, evidence for a targeted semantic category is often sparsely located across time. To address the issue, a segmental multi-way local feature pooling method by using scene concept analysis is proposed. In particular, the proposed method utilizes scene concepts that are pre-constructed by clustering video segments into categories in an unsupervised manner. Then, a video is represented with multiple feature descriptors with respect to scene concepts. Finally, multiple kernels are constructed from the feature descriptors, and then, are combined into a final kernel that improves the discriminative power for multimedia event detection.
Another challenge is that most semantic categories used for multimedia retrieval have inherent within-class diversity that can be dramatic and can raise the question as to whether conventional approaches are still successful and scalable. To consider such huge variability and further improve recounting capabilities, a per-exemplar learning scheme is proposed with a focus on fusing multiple types of heterogeneous features for video retrieval. While the conventional approach for multimedia retrieval involves learning a single classifier per category, the proposed scheme learns multiple detection models, one for each training exemplar. In particular, a local distance function is defined as a linear combination of element distance measured by each features. Then, a weight vector of the local distance function is learned in a discriminative learning method by taking only neighboring samples around an exemplar as training samples. In this way, a retrieval problem is redefined as an association problem, i.e., test samples are retrieved by association-based rules.
In addition, the quality of a multimedia-retrieval system is often evaluated by domain-specific performance metrics that serve sophisticated user needs. To address such criteria for evaluating a multimedia-retrieval system, in MFoM learning, novel algorithms were proposed to explicitly optimize two challenging metrics, AP and a weighted sum of the probabilities of false alarms and missed detections at a target error ratio. Most conventional learning schemes attempt to optimize their own learning criteria, as opposed to domain-specific performance measures. By addressing this discrepancy, the proposed learning scheme approximates the given performance measure, which is discrete and makes it difficult to apply conventional optimization schemes, with a continuous and differentiable loss function which can be directly optimized. Then, a GPD algorithm is applied to optimizing this loss function.
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Cunningham, Dustin T. "Fusion of Multimodal Neuroimaging for Deep Brain Stimulation Studies." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1337895443.
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Pappalardo, Maria. "Misure sperimentali e analisi statistica per la valutazione dell'accuratezza dimensionale di campioni realizzati mediante fabbricazione additiva." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
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Il presente studio ha posto le basi per la generazione di modelli di correlazione tra parametri di processo e parametri di qualità del prodotto per la tecnologia Multi Jet Fusion. Poiché l'accuratezza dimensionale è ad oggi il principale limite all'applicazione industriale di questa tecnologia, si è deciso di effettuare delle osservazioni e delle misure sperimentali su apposite geometrie benchmark di piccole e medio-grandi dimensioni rispetto allo spazio di costruzione offerto dal sistema HP Jet Fusion 3D 4200. La pianificazione di tali esperimenti è avvenuta con l'obiettivo di generare un modello di correlazione tra l'accuratezza dimensionale e alcuni parametri di processo, quali: dimensione nominale, irradianza ed orientamento.
Nello specifico, il lavoro è stato suddiviso come segue. Nel primo capitolo sono state illustrate alcune caratteristiche generali dei processi additivi, per poi passare a descrivere in maniera più dettagliata la tecnologia Multi Jet Fusion. Tale processo è stato analizzato nel capitolo successivo in tutte le sue fasi, dalla progettazione ad hoc dei componenti fino alla fase di post-produzione, ponendo particolare attenzione ai parametri di processo che influenzano la qualità dei componenti stampati. Il terzo capitolo è stato dedicato all’analisi della progettazione degli esperimenti, durante la quale si è messo in evidenza i parametri di processo inclusi e quelli trascurati. Sempre in questo capitolo, sono stati descritti i metodi di misurazione utilizzati, ovvero un calibro digitale e una bilancia di precisione digitale. Infine, nell'ultimo capitolo sono stati descritti e commentati i risultati delle misure effettuate e della loro elaborazione, che è avvenuta per mezzo di tecniche statistiche quali: analisi dei residui, analisi della varianza e analisi di regressione polinomiale.
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Gessi, Luca. "Analisi e implementazione di tecniche di data fusion GNSS/IMU per localizzazione di precisione." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
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L'elaborato affronta l'implementazione di una tecnica di fusione dei dati inerziali, provenienti da accelerometro, giroscopio e magnetometro, con misure satellitari ricavate da scheda GNSS/RTK. Il sistema di posizionamento monta su carrello elevatore operante in ambito industriale.
Viene affrontata la modellazione dei sensori inerziali e la loro calibrazione.
Successivamente è stato implementato un generatore di traiettorie tramite il quale vengono simulate le misure dei sensori inerziali.
Infine, l’algoritmo di fusione, implementato tramite filtro di Kalman, è stato analizzato utilizzando i dati simulati.
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Pröschild, Annette. "Anato-metabolische Bildgebung der postischämischen Mitralinsuffizienz zweidimensionale Image-Fusion kardialer 18FDG-PET und EBT-Schnittbilder ; ein neues Konzept /." [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=965210677.
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McCutchan, Jennifer Susan. "Transferring ascochyta blight resistance from Lathyrus sp. into field pea (Pisum sativum L.) via protoplast fusion (somatic hybridisation) /." Connect to thesis, 2001. http://eprints.unimelb.edu.au/archive/00000696.
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Sampieri, Francesca. "Algoritmi per la misurazione degli angoli articolari degli arti superiori tramite sensori inerziali." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
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In questo studio si vogliono analizzare i diversi algoritmi proposti in letteratura necessari per la ricostruzione della cinematica articolare dell’arto superiore, analizzata tramite unità di misurazione inerziale wireless indossabili.
L’analisi quantitativa del movimento degli arti superiori del corpo umano può essere di grande utilità nella valutazione delle performance sportive, nella diagnostica, nel monitoraggio e nel trattamento riabilitativo di problemi articolari. Tuttavia, data la complessità dei movimenti consentiti dalle articolazioni degli arti superiori, solo recentemente, grazie allo sviluppo di nuove tecniche e tecnologie, la comunità scientifica ha iniziato a studiarne più nel dettaglio gli aspetti biomeccanici.
Negli ultimi anni lo sviluppo delle tecnologie MEMS, hanno portato alla produzione di dispositivi wireless inerziali/magnetici indossabili. Queste piattaforme multi-sensore si sono affermate nel mondo della Motion Capture poiché in grado di registrare ed elaborare in tempo reale i dati del movimento umano in modo del tutto non invasivo in ambienti quotidiani per periodi di tempo prolungati.
Per fare ciò è necessario utilizzare appositi algoritmi di sensor fusion che garantiscano l’accuratezza dei dati stimati a fronte dei numerosi errori che corrompono inevitabilmente le misurazioni effettuate dai singoli dispositivi integrati nelle piattaforme inerziali/magnetiche.
Le classi di algoritmi per la sensor fusion più comunemente utilizzate nell’analisi del movimento umano, e più in particolare nell’analisi degli angoli articolari degli arti superiori, sono: integrazione, osservazione vettoriale, filtraggio complementare e filtraggio di Kalman.
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Reig, Bolaño Ramon. "Aplicacions de tècniques de fusió de dades per a l'anàlisi d'imatges de satèl·lit en Oceanografia." Doctoral thesis, Universitat Politècnica de Catalunya, 2008. http://hdl.handle.net/10803/6351.
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Durant dècades s'ha observat i monitoritzat sistemàticament la Terra i el seu entorn des de l'espai o a partir de plataformes aerotransportades. Paral·lelament, s'ha tractat d'extreure el màxim d'informació qualitativa i quantitativa de les observacions realitzades. Les tècniques de fusió de dades donen un "ventall de procediments que ens permeten aprofitar les dades heterogènies obtingudes per diferents mitjans i instruments i integrar-les de manera que el resultat final sigui qualitativament superior". En aquesta tesi s'han desenvolupat noves tècniques que es poden aplicar a l'anàlisi de dades multiespectrals que provenen de sensors remots, adreçades a aplicacions oceanogràfiques. Bàsicament s'han treballat dos aspectes: les tècniques d'enregistrament o alineament d'imatges; i la interpolació de dades esparses i multiescalars, focalitzant els resultats als camps vectorials bidimensionals.En moltes aplicacions que utilitzen imatges derivades de satèl·lits és necessari mesclar o comparar imatges adquirides per diferents sensors, o bé comparar les dades d'un sòl sensor en diferents instants de temps, per exemple en: reconeixement, seguiment i classificació de patrons o en la monitorització mediambiental. Aquestes aplicacions necessiten una etapa prèvia d'enregistrament geomètric, que alinea els píxels d'una imatge, la imatge de treball, amb els píxels corresponents d'una altra imatge, la imatge de referència, de manera que estiguin referides a uns mateixos punts. En aquest treball es proposa una aproximació automàtica a l'enregistrament geomètric d'imatges amb els contorns de les imatges; a partir d'un mètode robust, vàlid per a imatges mutimodals, que a més poden estar afectades de distorsions, rotacions i de, fins i tot, oclusions severes. En síntesi, s'obté una correspondència punt a punt de la imatge de treball amb el mapa de referència, fent servir tècniques de processament multiresolució. El mètode fa servir les mesures de correlació creuada de les transformades wavelet de les seqüències que codifiquen els contorns de la línia de costa. Un cop s'estableix la correspondència punt a punt, es calculen els coeficients de la transformació global i finalment es poden aplicar a la imatge de treball per a enregistrar-la respecte la referència.
A la tesi també es prova de resoldre la interpolació d'un camp vectorial espars mostrejat irregularment. Es proposa un algorisme que permet aproximar els valors intermitjos entre les mostres irregulars si es disposa de valors esparsos a escales de menys resolució. El procediment és òptim si tenim un model que caracteritzi l'esquema multiresolució de descomposició i reconstrucció del conjunt de dades. Es basa en la transformada wavelet discreta diàdica i en la seva inversa, realitzades a partir d'uns bancs de filtres d'anàlisi i síntesi. Encara que el problema està mal condicionat i té infinites solucions, la nostra aproximació, que primer treballarem amb senyals d'una dimensió, dóna una estratègia senzilla per a interpolar els valors d'un camp vectorial bidimensional, utilitzant tota la informació disponible a diferents resolucions. Aquest mètode de reconstrucció es pot utilitzar com a extensió de qualsevol interpolació inicial. També pot ser un mètode adequat si es disposa d'un conjunt de mesures esparses de diferents instruments que prenen dades d'una mateixa escena a diferents resolucions, sense cap restricció en les característiques de la distribució de mesures. Inicialment cal un model dels filtres d'anàlisi que generen les dades multiresolució i els filtres de síntesi corresponents, però aquest requeriment es pot relaxar parcialment, i és suficient tenir una aproximació raonable a la part passa baixes dels filtres. Els resultats de la tesi es podrien implementar fàcilment en el flux de processament d'una estació receptora de satèl·lits, i així es contribuiria a la millora d'aplicacions que utilitzessin tècniques de fusió de dades per a monitoritzar paràmetres mediambientals.
During the last decades a systematic survey of the Earth environment has been set up from many spatial and airborne platforms. At present, there is a continuous effort to extract and combine the maximum of quantitative information from these different data sets, often rather heterogeneous. Data fusion can be defined as "a set of means and tools for the alliance of data originating from different sources with the aims of a greater quality result". In this thesis we have developed new techniques and schemes that can be applied on multispectral data obtained from remote sensors, with particular interest in oceanographic applications. They are based on image and signal processing. We have worked mainly on two topics: image registration techniques or image alignment; and data interpolation of multiscale and sparse data sets, with focus on two dimensional vector fields.
In many applications using satellite images, and specifically in those related to oceanographic studies, it is necessary to merge or compare multiple images of the same scene acquired from different captors or from one captor but at different times. Typical applications include pattern classification, recognition and tracking, multisensor data fusion and environmental monitoring. Image registration is the process of aligning the remotely sensed images to the same ground truth and transforming them into a known geographic projection (map coordinates). This step is crucial to correctly merge complementary information from multisensor data. The proposed approach to automatic image registration is a robust method, valid for multimodal images affected by distortions, rotations and, to a reasonably extend, with severe data occlusion. We derived a point to point matching of one image to a georeferenced map applying multiresolution signal processing techniques. The method is based on the contours of images: it uses a maximum cross correlation measure on the biorthogonal undecimated discrete wavelet transforms of the codified coastline contours sequences. Once this point to point correspondence is established, the coefficients of a global transform could be calculated and finally applied on the working image to register it to the georeferenced map.
The second topic of this thesis focus on the interpolation of sparse irregularly-sampled vector fields when these sparse data belong to different resolutions. It is proposed a new algorithm to iteratively approximate the intermediate values between irregularly sampled data when a set of sparse values at coarser scales is known. The procedure is optimal if there is a characterized model for the multiresolution decomposition / reconstruction scheme of the dataset. The scheme is based on a fast dyadic wavelet transform and on its inversion using a filter bank analysis/synthesis implementation for the wavelet transform model. Although the problem is ill-posed, and there are infinite solutions, our approach, firstly worked for one dimension signals, gives an easy strategy to interpolate the values of a vector field using all the information available at different scales. This reconstruction method could be used as an extension on any initial interpolation. It can also be suitable in cases where there are sparse measures from different instruments that are sensing the same scene simultaneously at several resolutions, without any restriction to the characteristics of the data distribution. Initially a filter model for the generation of multiresolution data and their synthesis counterpart is the main requisite but; this assumption can be partially relaxed with the only requirement of a reasonable approximation to the low pass counterpart. The thesis results can be easily implemented on the process stream of any satellite receiving station and therefore constitute a first contribution to potential applications on data fusion of environmental monitoring.
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Savalli, Antonino. "Tecniche analitiche per “Open Data”." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/17476/.
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L’ultimo decennio ha reso estremamente popolare il concetto di Open Government, un modello di amministrazione aperto che fonda le sue basi sui principi di trasparenza, partecipazione e collaborazione. Nel 2011, nasce il progetto Dati.gov.it, un portale che ha il ruolo di “catalogo nazionale dei metadati relativi ai dati rilasciati in formato aperto dalle pubbliche amministrazioni italiane”.
L'obiettivo della tesi è fornire un efficace strumento per ricercare, usare e confrontare le informazioni presenti sul portale Dati.gov.it, individuando tra i dataset similarità che possano risolvere e/o limitare l’eterogeneità dei dati presenti.
Il progetto consiste nello sviluppo su tre aree di studio principali: Standard di Open Data e Metadata, Record Linkage e Data Fusion. Nello specifico, sono state implementate sette funzioni contenute in un'unica libreria.
La funzione search permette di ricercare all'interno del portale dati.gov.it. La funzione ext permette di estrarre le informazioni da sette formati sorgente: csv, json, xml, xls, rdf, pdf e txt. La funzione pre-process permette il Data Cleaning. La funzione find_claims è il cuore del progetto, perché contiene l'algoritmo di Text Mining che stabilisce una relazione tra i dataset individuando le parole in comune che hanno una sufficiente importanza all'interno del contesto. La funzione header_linkage permette di trovare la similarità tra i nomi degli attributi di due dataset, consigliando quali attributi concatenare. In modo analogo, record_linkage permette di trovare similarità tra i valori degli attributi di due dataset, consigliando quali attributi concatenare. Infine, la funzione merge_keys permette di fondere i risultati di header_linkage e record_linkage.
I risultati sperimentali hanno fornito feedback positivi sul funzionamento dei principali metodi implementati per quanto concerne la similarità sintattica tra due dataset.
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Xia, Jun Hao. "Serious game per il crowdsourcing di dati sull'accessibilità urbana." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/8262/.
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L'obiettivo di questo documento di tesi è descrivere il design e lo sviluppo di uno strumento per la raccolta delle
segnalazioni di barriere architettoniche che possa coinvolgere il maggior numero possibile
di utenti attraverso un serious game, implementando meccaniche di gioco che incitino il suo utilizzo, e che
al tempo stesso sia divertente, anche grazie a contenuti tematici quali gli zombie, il tutto
attraverso una interfaccia semplice e funzionale. Le segnalazioni sono disponibili
pubblicamente attraverso Fusion Tables dove esse sono memorizzate, permettendo
inoltre di avere una visione globale delle criticità grazie alla visualizzazione su
Google Maps.
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Wankerl, Veronika [Verfasser], Denys [Akademischer Betreuer] Loeffelbein, and Markus [Akademischer Betreuer] Schwaiger. "Die diagnostische Wertigkeit der retrospektiven PET-MRT-Fusion bei Kopf-Hals-Tumoren / Veronika Wankerl. Gutachter: Markus Schwaiger ; Denys Loeffelbein. Betreuer: Denys Loeffelbein." München : Universitätsbibliothek der TU München, 2015. http://d-nb.info/1070624187/34.
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Rossetti, Federica. "Analisi sperimentale su una operazione di saldatura di componenti telaio motociclistico in lega di alluminio ottenuti per fusione." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amslaurea.unibo.it/1260/.
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Forghieri, Cristina <1975>. "Interazioni tra le glicoproteine D, B, H ed L critiche per la fusione indotta dal virus Herpes simplex." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/683/.
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Four glycoproteins (gD, gB, gH, and gL) are required for herpes simplex virus (HSV) entry into the cell and for cell-cell fusion in transfected cells. gD serves as the receptor-binding glycoprotein and as the trigger of fusion; the other three glycoproteins execute fusion between the viral envelope and the plasma or endocytic membranes. Little is known on the interaction of gD with gB, gH, and gL. Here, the interactions between herpes simplex virus gD and its nectin1 receptor or between gD, gB, and gH were analyzed by complementation of the N and C portions of split enhanced green fluorescent protein (EGFP) fused to the glycoproteins. Split EGFP complementation was detected between proteins designated gDN + gHC, gDN + gBC, and gHN + gBC + wtgD, both in cells transfected with two or tree glycoproteins and in cells transfected with the four glycoproteins, commited to form syncytia. The in situ assay provides evidence that gD interacts with gH and gB independently one of the other. We further document the interaction between gH and gB.
To elucidate which portions of the glycoproteins interact with each other we generated mutants of gD and gB. gD triggers fusion through a specialised domain, named pro-fusion domain (PFD), located C-terminally in the ectodomain. Here, we show that PFD is made of subdomains 1 and 2 (amino acids 260–285 and 285–310) and that each one partially contributed to herpes simplex virus infectivity. Chimeric gB molecules composed of HSV and human herpesvirus 8 (HHV8) sequences failed to reach the cell surface and to complement a gB defective virus. By means of pull down experiments we analyzed the interactions of HSV-HHV8 gB chimeras with gH or gD fused to the strep-tag. The gB sequence between aa residues 219-360 was identified as putative region of interaction with gH or critical to the interaction.
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Carrier-Vallières, Martin. "FDG-PET/MR Imaging for prediction of lung metastases in soft-tissue sarcomas of the extremities by texture analysis and wavelet image fusion." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=114330.
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Soft-tissue sarcoma (STS) of the extremities forms a relatively uncommon yet aggressive group of neoplasms with high metastatic risk of the disease. The vast majority of STS metastases occur in the lungs. Due to the general poor prognosis of patients diagnosed with STS lung metastases, there is a clinical need to identify relevant prognostic factors as early as possible in the course of staging and treatment management. Recent evidence suggests that positron emission tomography (PET) using fluorodeoxyglucose (FDG) and magnetic resonance (MR) imaging texture features have the potential to predict the outcome of tumours through the assessment of their microenvironment heterogeneity characteristics. The goal of this work is therefore to investigate FDG-PET and MR texture features as potential early predictors of lung metastasis risk in STS cancer of the extremities.In this study, a dataset of 35 patients with histologically proven STS of the extremities was retrospectively analyzed. All patients received pre-treatment FDG-PET and MR scans. MR imaging data comprised of T1-weighted, T2 fat-saturation (T2FS) and short tau inversion recovery (STIR) sequences. The median follow-up period was 29 months (range: 4 to 85 months). Thirteen patients from the dataset developed lung metastases. Six texture features from the gray-level co-occurrence matrix (GLCM) were extracted from the FDG-PET, MR and fused FDG-PET/MR scans. In addition, the maximum standard uptake value (SUVmax) of the tumours was included in the feature set. The fusion of FDG-PET and MR scans was carried out using the discrete wavelet transform (DWT) and a band-pass frequencies enhancement technique. Statistical analysis was performed using Spearman's correlation (rho), and multivariable modeling using logistic regression. The prediction performance of the different multivariable models was assessed using bootstrap resampling by calculating the area under the receiver-operating characteristics curve (AUC) and Matthews' correlation coefficient (MCC). The highest univariate prediction of lung metastases was attributed to the SUVmax metric (rho=0.6382, p<0.0001). Most texture features extracted from fused scans had higher Spearman's correlation with lung metastases than those extracted from separate scans. On separate scans, FDG-PET texture features were generally dominant over MR texture features. The highest multivariable prediction of lung metastases was found using fused scans and the following 4-parameters model: 0.94*SUVmax − 0.401*PET-T2FS/STIR--Variance − 6.7*PET-T1--Contrast − 165*PET-T1--Homogeneity + 140. This model reached rho=0.8255, p<0.0001 on the entire dataset and AUC=0.956±0.002, MCC=0.829±0.002 in bootstrap testing sets. Overall, this work indicates the strong potential of FDG-PET and MR texture features for the prediction of lung metastases in STS cancer of the extremities. Substantial prediction improvements were found using texture features from fused scans and multivariable modeling strategies compared to texture features extracted from separate scans and univariate analysis. Potentially, this could improve patient outcomes by allowing better personalization of treatments and the application of pre-emptive strategies to mitigate disease spread.Les sarcomes des tissus mous (STM) provenant des extrémités forment un groupe relativement rare de néoplasme avec un risque métastatique élevé. La grande majorité des métastases provenant des STM ont lieu dans les poumons, et le pronostique résultant est généralement faible. En ce sens, il est important d'identifier autant de facteurs pronostiques pertinents que possible au moment du diagnostique et de la gestion du traitement. Certains travaux récents ont permis de démontrer que les caractéristiques texturales d'images provenant de la tomographie par émission de positrons (TEP) utilisant le fluorodéoxyglucose (FDG) et l'imagerie par résonance magnétique (IRM) ont le potentiel de prédire l'évolution tumorale grâce à l'évaluation des propriétés d'hétérogénéité biologique des tumeurs. Donc, le but de ce travail est d'évaluer le potentiel des caractéristiques texturales d'images FDG-TEP et IRM en tant que prédicteur du risque de métastases aux poumons pour le cancer des STM provenant des extrémités. Dans cette étude, une cohorte de 35 patients diagnostiqués avec des STM aux extrémités a été rétrospectivement analysée. Tous les patients ont reçu un scan FDG-TEP et un scan IRM avant leur traitement. Les séquences IRM qui ont été utilisés dans l'analyse sont: T1, T2 par saturation des gras (T2FS) et STIR. Les patients ont été suivis sur une période médiane de 29 mois (intervalle: 4 à 85 mois). Treize patients de la cohorte ont développé des métastases aux poumons. Six caractéristiques texturales d'images provenant de la matrice de co-occurrence des niveaux de gris (GLCM) ont été extraites des scans FDG-PET, IRM et FDG-PET/IRM fusionnés. De plus, la valeur maximale de consommation standard des tumeurs (SUVmax) a été incluse dans l'analyse. La fusion des scans a été effectuée grâce à la transformée d'ondelettes discrètes et grâce à une technique de renforcement des fréquences passe-bandes. L'analyse statistique a été effectuée en utilisant la corrélation de Spearman (rho), et l'analyse multivariable en utilisant la régression logistique. Les performances de prédiction des différents modèles multivariables ont été évaluées en calculant 2 métriques à partir de la technique de ré-échantillonnage « bootstrap »: L'aire sous la courbe de fonctionnement (AUC) et le coefficient de corrélation de Matthews (MCC). La plus haute prédiction univariée est attribuée à SUVmax (rho=0.6382, p<0.0001). La plupart des caractéristiques texturales extraites des scans fusionnés possèdent des coefficients de corrélation Spearman plus haut que celles extraites des scans séparés. Dans le cas des scans séparés, les caractéristiques texturales provenant de FDG-TEP sont généralement dominantes par rapport à celles provenant des scans IRM. La plus haute prédiction multivariable est provenue des scans fusionnés avec le model suivant: 0.94*SUVmax − 0.401*PET-T2FS/STIR--Variance − 6.7*PET-T1--Contrast − 165*PET-T1--Homogeneity + 140. Ce model a atteint des résultats de rho=0.8255, p<0.0001 sur l'ensemble des patients et AUC=0.956±0.002, MCC=0.829±0.002 sur les ensembles de tests « bootstrap ». De façon générale, cette étude indique le fort potentiel des caractéristiques texturales provenant des images FDG-TEP et IRM pour prédire les métastases aux poumons dans le cas des patients atteints des STM aux extrémités. Une amélioration substantielle des prédictions a pu être obtenue en utilisant les caractéristiques texturales des scans fusionnés et des stratégies d'analyse multivariable comparativement aux caractéristiques texturales des scans séparés et à l'analyse univariée. Potentiellement, cela pourrait mener à l'application de stratégies préventives pour atténuer la propagation du cancer des STM et à l'application de traitements mieux adaptés aux besoins des patients.
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BRITO, Ana Calado. "Cinética de cristalização isotérmica e não isotérmica a frio do pet e das blendas PET/PHB em diferentes concentrações." Universidade Federal de Pernambuco, 2010. https://repositorio.ufpe.br/handle/123456789/6034.
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Previous issue date: 2010A cinética de cristalização do PET e Das blendas formadas por PET/PHB foi estudada por calorimetria exploratória diferencial (DSC). O principal ponto de interesse nesse estudo foi o pico de cristalização exotérmico observado nas curvas de DSC. Na cristalização isotérmica do PET e do PET/PHB, foi investigado o efeito de diferentes temperaturas nas suas taxas de cristalização a frio. Os parâmetros cinéticos da cristalização isotérmica foram determinados utilizando a teoria de Avrami. Foi observado que em baixas temperaturas a cristalização ocorre em dois estágios, já para temperaturas mais elevadas ocorre em apenas um estágio. O expoente de Avrami n, a constante de velocidade K e o meio tempo de cristalização t0,5 foram analisados para a cristalização isotérmica a frio do PET e do PET/PHB. A constante K aumentou com a temperatura de cristalização, t0,5 diminuiu com o aumento da temperatura de cristalização. Com relação ao expoente n, os valores apresentados ficaram próximos de 2 definindo uma morfologia em forma de disco. Com a adição do PHB ao PET, houve um aumento na cristalinidade do homopolímero PET. A cinética de cristalização isotérmica nos possibilita ter um controle sobre as condições de cristalização através do tempo para uma dada temperatura, já na cristalização não isotérmica, esse controle está diretamente ligado a taxa de aquecimento durante a formação dos cristais, variando a temperatura em relação ao tempo. A cinética de cristalização não isotérmica foi investigada e os parâmetros cinéticos foram determinados através da teoria de Mo para diferentes taxas de aquecimento e verificou-se que o expoente de Mo a apresentou valores próximos a 1, a constante de velocidade K (T) aumentou tanto com o aumento da temperatura de cristalização quanto com a adição de PHB ao PET, e F(T) apresentou valores mais baixos para as blendas indicando um aumento da velocidade de cristalização
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Sabater, i. Pruna Assumpta. "Un model d'incertesa fitada per a la propagació i fusió d'informació geomètrica incerta." Doctoral thesis, Universitat Politècnica de Catalunya, 1996. http://hdl.handle.net/10803/6659.
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En esta tesis se desarrolla un sistema de tratamiento de informaciones geométricas con incertidumbre, basado en la propagación y fusión de regiones elipsoidales. Se adopta un modelo de incertidumbre acotada en el espacio de parámetros por conjuntos elipsoidales. Estos conjuntos pueden ser degenerados o no, permitiendo representar tanto informaciones parciales como completas de los elementos observados.Se ha obtenido una formula para calcular la fusión de dos elipsoides. Es decir, que dadas varias observaciones de un mismo elemento, cada una con su región elipsoidal de incertidumbre, la operación de fusión calcula la menor cota elipsoidal.
La propagación de elipsoides se hace a través de las ecuaciones correspondientes a las relaciones geométricas entre los elementos del entorno. Se ha obtenido una formula que generaliza la propagación de elipsoides a los casos degenerados usando matrices pseudoinversas y permitiendo así también la propagación de informaciones parciales.
Se presenta un algoritmo para la actualización global de las informaciones que se basa en la fusión y la propagación. Se implementa sobre un grafo cuyos nodos representan los elementos del entorno y cuyos arcos representan las relaciones entre ellos.
Finalmente se expone, como ejemplo de aplicación del sistema desarrollado, un algoritmo para la imposición de condiciones de consistencia en dibujos poligonales con posición inserta de los vértices, para ser proyecciones bidimensionales de poliedros. Las condiciones de consistencia se definen de forma natural en el grafo y la imposición se hace con el algoritmo de propagación global.
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Irace, Zacharie. "Modélisation statistique et segmentation d'images TEP : application à l'hétérogénéité et au suivi de tumeurs." Phd thesis, Toulouse, INPT, 2014. http://oatao.univ-toulouse.fr/12201/1/irace.pdf.
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Cette thèse étudie le traitement statistique des images TEP. Plus particulièrement, la distribution binomiale négative est proposée pour modéliser l’activité d’une région mono-tissulaire. Cette représentation a l’avantage de pouvoir prendre en compte les variations d’activité biologique (ou hétérogénéité) d’un même tissu. A partir de ces résultats, il est proposé de modéliser la distribution de l’image TEP entière comme un mélange spatialement cohérent de lois binomiales négatives. Des méthodes Bayésiennes sont considérées pour la segmentation d’images TEP et l’estimation conjointe des paramètres du modèle. La cohérence spatiale inhérente aux tissus biologiques est modélisée par un champ aléatoire de Potts-Markov pour représenter la dépendance locale entre les composantes du mélange. Un algorithme original de Monte Carlo par Chaîne de Markov (MCMC) est utilisé, faisant appel aux notions d’échantillonnage dans un espace Riemannien et d’opérateurs proximaux. L’approche proposée est appliquée avec succès à la segmentation de tumeurs en imagerie TEP. Cette méthode est ensuite étendue d’une part en intégrant au processus de segmentation des informations anatomiques acquises par tomodensitométrie (TDM), et d’autre part en traitant une série temporelle d’images correspondant aux différentes phases de respiration. Un modèle de mélange de distributions bivariées binomiale négative - normale est proposé pour représenter les images dynamiques TEP et TDM fusionnées. Un modèle Bayésien hiérarchique a été élaboré comprenant un champ de Potts-Markov à quatre dimensions pour respecter la cohérence spatiale et temporelle des images PET-TDM dynamiques. Le modèle proposé montre une bonne qualité d’ajustement aux données et les résultats de segmentation obtenus sont visuellement en concordance avec les structures anatomiques et permettent la délimitation et le suivi de la tumeur.
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Lian, Chunfeng. "Information fusion and decision-making using belief functions : application to therapeutic monitoring of cancer." Thesis, Compiègne, 2017. http://www.theses.fr/2017COMP2333/document.
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La radiothérapie est une des méthodes principales utilisée dans le traitement thérapeutique des tumeurs malignes. Pour améliorer son efficacité, deux problèmes essentiels doivent être soigneusement traités : la prédication fiable des résultats thérapeutiques et la segmentation précise des volumes tumoraux. La tomographie d’émission de positrons au traceur Fluoro- 18-déoxy-glucose (FDG-TEP) peut fournir de manière non invasive des informations significatives sur les activités fonctionnelles des cellules tumorales. Les objectifs de cette thèse sont de proposer: 1) des systèmes fiables pour prédire les résultats du traitement contre le cancer en utilisant principalement des caractéristiques extraites des images FDG-TEP; 2) des algorithmes automatiques pour la segmentation de tumeurs de manière précise en TEP et TEP-TDM. La théorie des fonctions de croyance est choisie dans notre étude pour modéliser et raisonner des connaissances incertaines et imprécises pour des images TEP qui sont bruitées et floues. Dans le cadre des fonctions de croyance, nous proposons une méthode de sélection de caractéristiques de manière parcimonieuse et une méthode d’apprentissage de métriques permettant de rendre les classes bien séparées dans l’espace caractéristique afin d’améliorer la précision de classification du classificateur EK-NN. Basées sur ces deux études théoriques, un système robuste de prédiction est proposé, dans lequel le problème d’apprentissage pour des données de petite taille et déséquilibrées est traité de manière efficace. Pour segmenter automatiquement les tumeurs en TEP, une méthode 3-D non supervisée basée sur le regroupement évidentiel (evidential clustering) et l’information spatiale est proposée. Cette méthode de segmentation mono-modalité est ensuite étendue à la co-segmentation dans des images TEP-TDM, en considérant que ces deux modalités distinctes contiennent des informations complémentaires pour améliorer la précision. Toutes les méthodes proposées ont été testées sur des données cliniques, montrant leurs meilleures performances par rapport aux méthodes de l’état de l’artRadiation therapy is one of the most principal options used in the treatment of malignant tumors. To enhance its effectiveness, two critical issues should be carefully dealt with, i.e., reliably predicting therapy outcomes to adapt undergoing treatment planning for individual patients, and accurately segmenting tumor volumes to maximize radiation delivery in tumor tissues while minimize side effects in adjacent organs at risk. Positron emission tomography with radioactive tracer fluorine-18 fluorodeoxyglucose (FDG-PET) can noninvasively provide significant information of the functional activities of tumor cells. In this thesis, the goal of our study consists of two parts: 1) to propose reliable therapy outcome prediction system using primarily features extracted from FDG-PET images; 2) to propose automatic and accurate algorithms for tumor segmentation in PET and PET-CT images. The theory of belief functions is adopted in our study to model and reason with uncertain and imprecise knowledge quantified from noisy and blurring PET images. In the framework of belief functions, a sparse feature selection method and a low-rank metric learning method are proposed to improve the classification accuracy of the evidential K-nearest neighbor classifier learnt by high-dimensional data that contain unreliable features. Based on the above two theoretical studies, a robust prediction system is then proposed, in which the small-sized and imbalanced nature of clinical data is effectively tackled. To automatically delineate tumors in PET images, an unsupervised 3-D segmentation based on evidential clustering using the theory of belief functions and spatial information is proposed. This mono-modality segmentation method is then extended to co-segment tumor in PET-CT images, considering that these two distinct modalities contain complementary information to further improve the accuracy. All proposed methods have been performed on clinical data, giving better results comparing to the state of the art ones
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Niehues, Stefan Markus. "Stellenwert der Bildfusion von Positronenemissionstomographie und Computertomographie bei onkologischen Erkrankungen des Pankreas." Doctoral thesis, [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=964361043.
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Silva, Lucas José da [UNESP]. "Desenvolvimento e aplicação de microplumas para tratamento de politereftalato de etileno (PET)." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/127970.
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000847906.pdf: 2134043 bytes, checksum: d544b7fcf68a15d44f48104dd4595087 (MD5)Este trabalho descreve o desenvolvimento de um dispositivo de geração de microdescargas de plasma operando à pressão atmosférica, sua caracterização e aplicação no tratamento de superfície polimérica. A microdescarga é produzida entre uma agulha e um eletrodo externo na forma de um cilindro. A agulha e o cilindro são dispostos coaxialmente com um capilar de borossilicato ou quartzo entre os mesmos. O sinal usado para excitar a descarga tinha a forma senoidal na frequência de 37 kHz. Estas microdescargas produziram plumas de plasma na extremidade da agulha. Medições da tensão de ruptura mostraram regimes distintos conforme a posição axial do cilindro em relação à agulha. Simulações com circuitos mostraram diferentes circuitos equivalentes ao dispositivo de microdescarga conforme esta posição relativa entre os eletrodos. Utilizando estas plumas no tratamento de superfícies de PET verificou-se redução do ângulo de contato com o tratamento que atinge um mínimo para tempos de 10 s. O ângulo de contato para diferentes posições em torno do ponto de tratamento foi ajustado à curvas baseadas em funções gaussiana e lorentziana. Isto possibilitou verificar o aumento da área tratada com o fluxo do gás quando a tensão na descarga se torna elevada. Para pluma de diâmetro menor que 1 mm o tratamento se estendeu em até 6 mm devido a dinâmica do gás da pluma. O dispositivo se mostrou confiável e com tratamento reprodutível na modificação das propriedades da superfície de materiais
This work describes the development and characterization of a microplasma jet device operating at atmospheric pressure and its application on the treatment of a polymeric surface. The micro discharge was produced between a needle and a coaxial cylindrical electrode with a borosilicate or quartz capillary between them. The discharge occurs in a small gap between the capillary and the needle and a plasma plume is produced at the tip of the needle. The signal used to excite the discharge was sinusoidal at frequency of 37 kHz. Breakdown voltage measurement showed distinct regimes according to the axial position of the cylinder relative to the needle. Simulations showed different equivalent circuits for the device according to the relative position between the electrodes. The plasma plumes were used to treat PET surfaces. It was observed the reduction of the contact angle with the treatment time that saturates around 10 s. The contact angle measurements at different positions around the treatment point were fitted using Gaussian and Lorentzian functions in order to estimate the diameter of treated circular area around the contact point of the plume with the surface. It was observed an increase of the treated area with the flow rate gas particularly at high applied voltage. Diameter up to 6 mm was achieved for plasma plumes with diameter smaller than 1 mm due to gas dynamic effects. The repeatability on the treatment showed that the plasma jet is reliable to modify surface properties of materials
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Silva, Lucas José da. "Desenvolvimento e aplicação de microplumas para tratamento de politereftalato de etileno (PET) /." Guaratinguetá, 2015. http://hdl.handle.net/11449/127970.
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Orientador: Milton Eiji KayamaBanca: Konstantin Georgiev Koslov
Banca: Tessie Gouvea da Cruz
Resumo: Este trabalho descreve o desenvolvimento de um dispositivo de geração de microdescargas de plasma operando à pressão atmosférica, sua caracterização e aplicação no tratamento de superfície polimérica. A microdescarga é produzida entre uma agulha e um eletrodo externo na forma de um cilindro. A agulha e o cilindro são dispostos coaxialmente com um capilar de borossilicato ou quartzo entre os mesmos. O sinal usado para excitar a descarga tinha a forma senoidal na frequência de 37 kHz. Estas microdescargas produziram plumas de plasma na extremidade da agulha. Medições da tensão de ruptura mostraram regimes distintos conforme a posição axial do cilindro em relação à agulha. Simulações com circuitos mostraram diferentes circuitos equivalentes ao dispositivo de microdescarga conforme esta posição relativa entre os eletrodos. Utilizando estas plumas no tratamento de superfícies de PET verificou-se redução do ângulo de contato com o tratamento que atinge um mínimo para tempos de 10 s. O ângulo de contato para diferentes posições em torno do ponto de tratamento foi ajustado à curvas baseadas em funções gaussiana e lorentziana. Isto possibilitou verificar o aumento da área tratada com o fluxo do gás quando a tensão na descarga se torna elevada. Para pluma de diâmetro menor que 1 mm o tratamento se estendeu em até 6 mm devido a dinâmica do gás da pluma. O dispositivo se mostrou confiável e com tratamento reprodutível na modificação das propriedades da superfície de materiais
Abstract: This work describes the development and characterization of a microplasma jet device operating at atmospheric pressure and its application on the treatment of a polymeric surface. The micro discharge was produced between a needle and a coaxial cylindrical electrode with a borosilicate or quartz capillary between them. The discharge occurs in a small gap between the capillary and the needle and a plasma plume is produced at the tip of the needle. The signal used to excite the discharge was sinusoidal at frequency of 37 kHz. Breakdown voltage measurement showed distinct regimes according to the axial position of the cylinder relative to the needle. Simulations showed different equivalent circuits for the device according to the relative position between the electrodes. The plasma plumes were used to treat PET surfaces. It was observed the reduction of the contact angle with the treatment time that saturates around 10 s. The contact angle measurements at different positions around the treatment point were fitted using Gaussian and Lorentzian functions in order to estimate the diameter of treated circular area around the contact point of the plume with the surface. It was observed an increase of the treated area with the flow rate gas particularly at high applied voltage. Diameter up to 6 mm was achieved for plasma plumes with diameter smaller than 1 mm due to gas dynamic effects. The repeatability on the treatment showed that the plasma jet is reliable to modify surface properties of materials
Mestre
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Nicolini, Andrea. "Multipath tracking techniques for millimeter wave communications." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/17690/.
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L'obiettivo di questo elaborato è studiare il problema del tracciamento efficiente e continuo dell'angolo di arrivo dei cammini multipli dominanti in un canale radio ad onde millimetriche. In particolare, viene considerato uno scenario di riferimento in cui devono essere tracciati il cammino diretto da una stazione base e due cammini riflessi da ostacoli in diverse condizioni operative e di movimento dell'utente mobile. Si è assunto che l'utente mobile può effettuare delle misure rumorose di angolo di arrivo dei tre cammini, uno in linea di vista e gli altri due non in linea di vista, ed eventualmente delle misure di distanza tra esso e le tre "sorgenti" (ad esempio ricavandole da misure di potenza ricevuta). Utilizzando un modello "spazio degli stati", sono stati investigati due diversi approcci: il primo utilizza un fitraggio di Kalman direttamente sulle misure di angolo di arrivo, mentre il secondo adotta un metodo a due passi in cui lo stato è rappresentato dalle posizioni della stazione base e dei due ostacoli, dalle quali vengono valutate le stime degli angoli di arrivo. In entrambi i casi è stato investigato l'impatto che ha sulla stima la fusione dei dati ottenuti dai sensori inerziali integrati nel dispositivo, ovvero velocità angolare ed accelerazione del mobile, con le misure di angolo di arrivo. Successivamente ad una fase di modellazione matematica dei due approcci, essi sono stati implementati e testati in MATLAB, sviluppando un simulatore in cui l'utente possa scegliere il valore di vari parametri a seconda dello scenario desiderato. Le analisi effettuate hanno mostrato la robustezza delle strategie proposte in diverse condizioni operative.
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Valiente, Bermejo María Asunción. "Modelització del nivell de ferrita "delta" (FN) als acers inoxidables austenítics sotmesos a fusió per arc elèctric." Doctoral thesis, Universitat de Barcelona, 2010. http://hdl.handle.net/10803/1081.
Full textAbstract:
Aquest estudi mostra els resultats experimentals obtinguts en analitzar el nivell de ferrita "delta" residual en condicions de velocitat de refredament per arc elèctric, així com els resultats de la determinació experimental de la ràtio críticaCr(eq)/Ni(eq) en la que es produeix la transició entre els modes de solidificació primaris [AP] i [FA]. Per això s'han preparat dues sèries de mostres d'acers inoxidables austenítics mitjançant forn de refusió amb arc elèctric, de manera que s'han mantingut els nivells d'aliatge constants (Cr(eq)+Ni(eq))=30% i (Cr(eq)+Ni(eq))=40% i s'ha anat variant la ràtio Cr(eq)/Ni(eq) entre 1.22 i 2.00 a cada sèrie.
De forma complementària s'ha validat la metodologia emprada, determinant experimentalment l'ordre de magnitud de les velocitats de refredament a les que s'ha sotmès el metall, quantificant les variacions de composició química experimentades pel material en ser refós per arc elèctric i optimitzant el procediment experimental en la preparació de mostres per arc elèctric en forn d'atmosfera inert.
Els resultats obtinguts han permès determinar la importància de les variables (Cr(eq))+Ni(eq)) i (Cr(eq)/Ni(eq)) en la microestructura dels acers inoxidables austenítics, de manera que s'ha modelitzat el nivell de ferrita "delta" en funció d'aquestes dues variables. A partir d'aquest model establert pels inoxidables austenítics fosos en les condicions marcades per l'arc elèctric, només coneixent la composició química del material es pot aconseguir predir el nivell de ferrita diferint de l'experimental entre (-1.11,+3.13) FN amb una fiabilitat del 95%. La informació obtinguda en aquest estudi sobre l'evolució microestructural de les mostres en funció de la composició química en les condicions de fusió per arc elèctric, pot ser de molta utilitat en el camp de la soldadura, donat que aporta una informació complementaria al diagrama de fases Fe-Cr-Ni.
This research showed the experimental results obtained when analysing the level of residual "delta" ferrite under electric arc cooling rate conditions. Results in the experimental determination of the Cr(eq)/Ni(eq) critical ratio at which the transition between [AF] and [FA] primary solidification modes are also depicted. With this aim, two series of austenitic stainless steel samples have been prepared using an arc electric remelting furnace, keeping the alloying level constant at (Cr(eq)+Ni(eq)=30% and (Cr(eq)+Ni(eq))=40% and increasing the Cr(eq)/Ni(eq) ratio from 1.22 up to 2.00 in each series.
Additionally, the methodology used has been validated experimentally, establishing the order of magnitude of the cooling rates followed by the metal, assessing the variations in chemical compositions experienced by the materials while being remelted by electric arc and optimizing the experimental procedure for samples preparation using arc electric remelting furnace under inert gas protection.
The results obtained have led to the importance of the variables (Cr(eq)+Ni(eq)) and (Cr(eq)/Ni(eq)) in the microstructure of austenitic stainless steels, and a model for the "delta" ferrite content has been proposed according to both variables. As a consequence of the modelling established for austenitic stainless steels, melted and solidified according to electric arc conditions, it is possible to forecast the level of "delta" ferrite within a 95% reliability between (1.11,+3.13)FN just considering the chemical composition of the alloy. The information provided in this research regarding the microstructural evolution of the samples in terms of the chemical composition under electric arc melting and cooling conditions can be helpful in the welding industry, as it provides complementary information to the Fe-Cr-Ni phase diagram.
KEY WORDS: Delta-ferrite, Austenitic stainless Steels, Electric Arc, Welding, Materials Technology
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Alves, Jose Guilherme Lembi Ferreira. "Estudo do equilibrio liquido-liquido, da partição de insulina e da pre-purificação da proteina de fusão precursora da insulina humana em sistemas aquosos bifasicos do tipo PEG/Sal." [s.n.], 2003. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254966.
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Orientador : Antonio Jose de Almeida MeirellesTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: Neste trabalho foi estudada a pré-purificação da proteína de fusão precursora à insulina humana e produzida por Escherichia coli modificada, utilizando-se Sistemas Aquosos Bifásicos do tipo polietileno glicol (PEG)/sal/água. A proteína de fusão foi fornecida pela empresa farmacêutica Biobrás S.A (Montes Claros/MG) e foi dissolvida em uréia 8M. Os experimentos de partição da proteína de fusão foram conduzidos de forma a identificar condições para a separação da proteína de fusão de outras proteínas e componentes celulares de E. coli. Foram realizados dois planejamentos experimentais 32 para o estudo da partição da proteína de fusão precursora da insulina humana no sistema PEG/fosfato de potássio/água. tendo-se como variáveis a massa molar do polietileno glicol, a razão mássica PEG/fosfato do sistema (RPEG/FOS). OS níveis estudados foram 1500, 3350 e 8000 para a massa molar do PEG; 1,6, 1,636 e 1,67 para RPEG/FOS. No primeiro planejamento, os testes de partição foram conduzidos a pH 9, enquanto que no segundo planejamento, os testes foram conduzidos a pH 12. Concluídos os testes com o sistema PEG/fosfato de potássio/água, foi escolhida a melhor condição para a purificação da proteína de fusão, condição esta que foi também testada para o sistema PEG/citrato de sódio/água. Para o sistema PEG/fosfato de potássio/água, o melhor resultado foi obtido com o PEG de massa molar 1500, concentração de 16% p/p PEG/l0% p/p de fosfato e pH 9, com fator de purificação da ordem de 1,5 vez e recuperação de 99%. Nestas mesmas condições, mas utilizando citrato de sódio, o fator de purificação e a recuperação foram 1,8 vez e 50,0%, respectivamente. Para analisar a proteína de fusão precursora da insulina humana, desenvolveu-se uma metodologia de análise por Cromatografia de afinidade / FPLC, usando-se a coluna Chelating Sepharose para separar a proteína de fusão dos demais componentes celulares e o Método de Bradford para quantificá-1a. Diagramas de fase do sistema PE& Na3Cit/H2O, para 3 pesos moleculares de PEG (600, 1500 e 3000) foram medidos a 25°C e modelou-se o equilíbrio líquido-líquido deste sistema usando-se o modelo VERS, baseado na equação do virial e que usa como medida de concentração uma fração de superfície externa do componente. Um ajuste muito bom aos dados experimentais foi obtido e os erros absolutos médios entre as concentrações experimentais dos componentes e as calculadas pelo modelo VERS foram 1,16%, 1,05% e 1,19% para os sistemas PEG600/ Na3Cit/H2O, PEGl500/ Na3Cit/H2O e PEG3000/ Na3Cit/H2O, respectivamente. O modelo obtido apresentou boa capacidade preditiva para a influência da massa molar do PEG sobre o equilíbrio líquido-líquido do sistema estudado. Para fins de modelagem termodinâmica, também foi estudada a partição das insulinas humana e suína puras nos sistemas PEG600/ Na3Cit/H2O, PEG1450/Na3Cit/ H2O e PEG3350/Na3Cit/ H2O em pH 4,5, 7 e 9,5 a 25°C para modelar a partição da insulina no sistema PEG/ Na3Cit/ H2O, utilizando-se também o modelo VERS e bons resultados foram obtidos para a -predição do coeficiente de partição da insulina suína no sistema PEG/ Na3Cit/H2O a pH 7,0
Abstract: In this work the primary purification of a fusion protein precursor of human insulin and produced by recombinant E. coli has been studied using aqueous two-phase systems. The fusion protein was provided by the pharmaceutical company Biobrás S.A (Montes Claros/Brazil) and was dissolved in 8M area. Partitioning essays of fusion protein were investigated in the poly(ethylene glycol) (PEG)/potassium phosphate and poly(ethylene glycol)/sodium citrate aqueous two-phase systems at 25°C. Two 32 experimental design were done to evaluate the effects of PEG molecular weight and the polymer/salt concentration ratio on the purification factor and on the recovery of the fusion protein in the top phase. The studied levels were 1500, 3350 and 8000 for PEG molecular weight and 1,6; 1,636 and 1,67 for the polymerlsaIt concentration ratio. The partitioning experiments were performed at pH 9 and 12. An analytical method for the fusion protein was developed using Immobilized Metal Affinity Chromatography and the Bradford method. Solids on the interface top were observed in all cases examined The fusion protein partitioned between the PEG-rich phase and the solids on interface. Contaminating proteins were eliminated to some extent, which resulted in an almost 2-fold fusion protein purification with good recoveries. Phase diagrams of the system poly(ethylene glycol)1 sodium citrate/water were determined for three different molecular weights of PEG ( 600, 1500, 3000) at 25°C. At least four tie-lines of each system were measured. The experimental results were correlated by applying a model for the excess Gibbs energy. This model is the Virial equation used by Pitzer for salt solutions, but concentrations are expressed by surface fraction. It is called Virial Equation with Relative Surface fractions (VERS). All phase equilibrium calculations were performed using this model and minimizing the Gibbs energy of the feed under the constraint that both phases are electroneutral. Agreement between the experimental and calculated results within the experimental uncertainty was obtained. The average percents of deviation between experimental and calculated values using VERS model for all components were 1,16%, 1,05% and 1,19% for the systems PEG6001 Na3Cit/H2O, PEGl500/ Na3Cit/H2O PEG30001 Na3Cít/ H2O respectively. Human and porcine insulin partitioning was investigated in the system PEG/sodium citrate/water for three pHs (4,5; 7 and 9,5) at 25°C. Human and porcine insulin showed great affinity for the PEG-rich phase and the partition coefficients were higher than 10. The human insulin partition coefficient is practically independent of the PEG molecular mass. However, there is a tendency for the porcine insulin partition coefficient to increase with the PEG molecular mass at pH 7 and 9,5, attaining values- above 50. The porcine insulin partition coefficient was predicted in the system PEG/sodium citrate/water at 25°C using VERS model and good results were obtained for the system at pH 7
Doutorado
Mestre em Engenharia de Alimentos
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Filipponi, Alessandro. "Modellizzazione petrogenetica dell’origine e dell’evoluzione dei complessi intrusivi di Predazzo e dei Monti Monzoni." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/15559/.
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I Complessi Intrusivi di Predazzo e dei Monti Monzoni hanno età Ladinica (circa 220-240 Ma) e sono intrusi nelle sequenze carbonatiche del Triassico medio-inferiore delle Dolomiti Occidentali. L’affinità shoshonitica che li caratterizza è in apparente contrasto con il regime geodinamico estensionale esistente. Le teorie evolutive proposte per motivare questa impronta sono molteplici: fusione parziale di un mantello metasomatizzato, subduzione, transpressione, miscelamento tra magmi mantellici e crostali. Tutte le analisi disponibili in letteratura definiscono, su diagrammi di Harker e multielemento normalizzati, trend evolutivi coerenti tipici di suite comagmatiche. La modellizzazione di un mantello in risalita adiabatica mostra che è possibile ottenere un fuso parentale arricchito in elementi incompatibili fondendo parzialmente una piccola percentuale (2-3%) di mantello eterogeneo costituito da un Mantello Primitivo (96-97%) e una piccola frazione (3-4%) di Mantello metasomatizzato ad anfibolo simile a quello affiorante nella Zona d’Ultimo. I risultati della modellizzazione sono stati confrontati con i liquidi parentali proposti in letteratura, come il gabbro CB13. Anche se le concentrazioni calcolate di Nb e di Sr si discostano da quelle osservate, gli altri elementi in traccia sono perfettamente riprodotti dalla modelizzazione. Si riesce a riprodurre la maggior parte delle litologie presenti nei due Complessi Intrusivi per cristallizzazione frazionata a partire da un unico fuso a composizione CB13.
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Santos, Denise Takehana dos. "Mapeamento topográfico metabólico de carcinomas espinocelulares de cabeça e pescoço utilizando a fusão de imagens 18 F-FDG PET - TC." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/23/23139/tde-09082005-124541/.
Full textAbstract:
O objetivo desta pesquisa foi estabelecer uma metodologia para avaliar carcinomas espinocelulares (CEC) de cabeça e pescoço, identificando e distinguindo áreas de maior atividade metabólica dentro da neoplasia, associando dados simultaneamente adquiridos, obtidos por diferentes modalidades de aquisição de imagens, combinando informações metabólicas e anatômicas num único exame. A população estudada consistiu de 17 pacientes com carcinoma espinocelular (CEC) de cabeça e pescoço pertencentes aos arquivos do Departamento de Imagem do Hospital do Câncer, São Paulo. As imagens de TC (tomografia computadorizada) e do 18 F-FDG-PET (tomografia por emissão de pósitrons) foram simultaneamente adquiridas utilizando um aparelho não dedicado. Os dados originais foram transferidos para uma estação de trabalho independente com programa de computação gráfica para o processamento dos grupos individuais e fusão em um único grupo, contendo os dados fisiológicos e metabólicos. Os achados foram definidos como positivos na presença de focos com aumento da concentração do radiofármaco em áreas não relacionadas à distribuição normal do mesmo. Em 77% dos casos (n=13), a hipercaptação foi detectada ao centro da lesão e em 23% (n=4) dos casos houve comportamento diferente, com hipercaptação excêntrica. A fusão de imagens simultaneamente adquiridas num único exame ( 18 F- FDG PET e TC) possibilitou o mapeamento topográfico metabólico das lesões estudadas e foi possível localizar áreas de maior atividade metabólica dentro do próprio 13 tumor, verificando recidivas ou metástases, possibilitando aumentar as opções quanto ao planejamento radioterápico ou cirúrgico a serem seguidos.The aim of this study is to propose a methodological approach to evaluate head and neck squamous cell carcinoma (SCCA) in order to identify and to distinguish areas of higher metabolic activity inside the lesion combining the functional metabolic and morphological data simultaneously acquired in a non dedicated PET-CT device. The study population consisted of 17 patients, with SCCA of the head and neck carcinoma. These patients were submitted to a non-dedicated 18 F- FDG- PET imaging using a system with low dose CT and Positron emission coincidence acquisition capabilities. The image acquisition was then transferred to an ENTEGRA 2 NT workstation to generate groups of individual images (metabolic and anatomical data) and image fusion (CT + PET). In those patients with anomalous concentrations of 18 F-FDG, the lesion was depicted on three planes (axial, coronal and sagittal) in CT, PET, and the image fusion at the computer screen. The findings were defined as positive in the presence of well-defined focal area of increased uptake in regions unrelated to the normal biodistribution of the tracer on visual inspection. Two examiners interpreted the images in different sessions, in order to get an agreement. Subsequently, the sites of higher metabolic activity inside the tumor were identified and classified in centric or eccentric, according to their relative location. Observing the images, we found 77.00% of the patients with the site of higher activity at the center of lesion. In 23.00% of the patients a different 15 behavior, with the tracer increased eccentrically to the lesion. This technique gave a realistic view of the functional metabolism, locating the anatomical tumor area and helping in future treatment planning.
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Sanchi, Matteo. "Analisi dell'introduzione di tecniche additive nel processo produttivo di airbox per il settore automotive." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/8540/.
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Analisi dell'introduzione di tecniche additive nel processo produttivo di airbox nel settore automotive, attraverso lo studio della tecnologia additiva e delle principali tecniche che ne fanno parte. Valutazione delle capacità delle tecniche additive per confrontarle con tecniche di produzione tradizionale, attraverso l'analisi prestazionale, dei costi e dei tempi di produzione.
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Begou, Patrick. "Distribution des éléments du groupe du platine et de l'or dans les roches basiques et ultrabasiques : approche de leur comportement géochimique orthomagmatique pendant les phénomènes de fusion partielle et de cristallisation fractionnée." Phd thesis, Grenoble 1, 1989. http://tel.archives-ouvertes.fr/tel-00682743.
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Les éléments du groupe du platine (POE) sont représentés, par l'osmium (Os),l'iridium (Ir), le ruthénium (Ru), le rhodium (Rh), le platine (Pt) etle palladium (Pd). L'or (Au) leur est fréquemment associé à cause de ses propriétés physico-chimiques voisines. Une méthode de dosage permettant la détermination de ces éléments (à l'exception de Os) à des teneurs d'ultratraces (inférieures ou égales au mg/t) a été développée dans notre laboratoire. Elle consiste en une coprécipitation et concentration de ces éléments par voie humide à haute température. Elle est associée à une détermination en spectrophotométrie d'absorption atomique électrothermique. Le matériel utilisé, la méthode analytique, son domaine d'application et ses limites font l'objet du premier chapitre. L'étude de la distribution des PGE dans le manteau supérieur est actuellement peu documentée. Avant d'aborder les mécanismes de fusion partielle ou de cristallisation fractionnée, il est nécessaire de tenter de définir une typologie géochimique la plus complète possible pour les teneurs en PGE des Iherzolites à spinelle du manteau supérieur sous continental. Le second chapitre est donc consacré à l'étude de l'écaille tectonique de lherzolites à spinelles de l'étang de Lherz (Ariège, France). La distribution des PGE dans ce complexe ultrabasique est caractérisée par une très faible pente des spectres de teneurs normalisées au manteau. Ils sont cependant fortement déprimés en Pt (< 0,5 ppb). Ce caractère a également été observé au cours d'autres analyses effectuées sur des Iherzolites à spinelle (Massif du Lubéron, Massif Central ... ) qui militent en faveur d'une généralisation de ce caractère. Les harzburgites associées aux lherzolites à spinelle de l'étang de Lherz ont permis d'aborder les phénomènes de fusion partielle et de contrôler la plus ou moins grande mobilisation des PGE par ces mécanismes. Les filons de pyroxénolites anhydre ou à amphibole ont permis par contre une approche du fractionnement magmatique dans un système ouvert: ils constituent en effet des conduits nourriciers indépendants recoupant la Iherzolite encaissante. Le comportement des PGE pendant le fractionnement d'un liquide silicaté est un phénomène complexe contrôlé par les coefflcients de partage, les paramètres thermodynamiques, la capacité en soufre du magma ... Le Filon Robert (Bande de Cape Smith, Québec, Canada) représente un liquide de type basalte komatiitique fractionné dans un système fermé. Son étude détaillée, à partir de l'évolution des teneurs calculées du liquide résiduel en équilibre avec les ségrégats fractionnés, nous a permis de caractériser plusieurs tendances au cours du fractionnement des PGE. Il est ainsi possible de mettre en évidence une précipitation des PGE contrôlée par les paramètres thermodynamiques, en étroite relation avec les caractéristiques des phases cristallisées. Cette analyse montre la complexité des mécanismes de fractionnement des PGE et souligne la non-représentativité d'une étude ne faisant intervenir qu'un seul processus de fractionnement dans ce contexte (normalisation à 100% de sulfures, diagrammes binaires de corrélation ... ). Elle montre également que dans les amas minéralisés ce ne seront pas forcement les niveaux les plus riches en sulfures qui possèderont les plus fortes teneurs en PGE.
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Rousová, Michaela. "Zvýšení efektivity při svařování pecních konstrukcí." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-229241.
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This diploma thesis is resolving all the possibilities of enhancing the efficiency of furnace structures welding. Small batch production does not offer many possibilities for implementing mechanization or automation. On the other hand, when using a big batch production, efficiency can be enhanced by means of a robotic workstation. When the production batch is big enough, we will see a costs save after a short time, mainly in labor costs. This means the return of investments will be in short time period. In the LAC company there are three types of products made. At laboratory furnaces the efficiency can be enhance by using fixtures. At other standard and atypical furnaces is very difficult to design fixtures or positioners because of their different sizes. Big complication can be also a company location on second floor. The most suitable product regarding to welding efficiency enhancement is big batch production of heaters. For this type the welding time can be shortened by means of a robotic workstation.
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Schön, Michael R. "Transplantation von Lebern nicht-herzschlagender Spender im Schweineleber-Transplantationsmodell." Doctoral thesis, Humboldt-Universität zu Berlin, Medizinische Fakultät - Universitätsklinikum Charité, 2000. http://dx.doi.org/10.18452/13727.
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Es wurde untersucht ob die normotherme extrakorporale Leberperfusion (NELP) als Methode geeignet ist, Lebern vor Transplantation zu konservieren, und ob sie warm ischämische Zellschäden beheben kann. Zum ersten Mal konnte experimentell gezeigt werden, daß eine erfolgreiche Transplantation nach 4 Stunden mit NELP möglich ist und sogar so zuverlässig, wie die Kaltkonservierung in der University of Wisconsin Lösung. Die NELP erhält die Leberfunktion und ermöglicht eine Regeneration warm ischämischer Schäden in Nicht-herzschlagenden Spendern. 36 Schweine der Deutschen Landrasse wurden in sechs Gruppen transplantiert. In der Gruppe 1 wurde direkt nach Organentnahme transplantiert, in Gruppe 2 nach 4 Stun-den Kaltkonservierung in der University of Wisconsin Lösung und in Gruppe 3 nach 4 Stunden NELP. In Gruppe 4 wurden die Lebern nach 60 Minuten warmer Ischämie direkt transplantiert, in Gruppe 5 nach 60 Minuten warmer Ischämie und 4 Stunden Kaltkonservierung und in Gruppe 6 nach 60 Minuten warmer Ischämie und 4 Stunden NELP. Alle Tiere deren Lebern vor Transplantation normotherm extrakorporal perfun-diert wurden (Gruppen 3 und 6) überlebten mit guter Organfunktion. Im Unterschied hierzu führte die Abfolge von 60 Minuten warmer Ischämie und 4 Stunden Kaltkonser-vierung unweigerlich zur primären Organ-Nichtfunktion innerhalb der ersten 24 Stun-den nach Lebertransplantation. Die Methode der NELP bietet die Chance eine Leber außerhalb des Körpers für Zeiträume von möglicherweise länger als 4 Stunden völlig funktionsfähig zu halten. Die NELP kann zur Organkonservierung vor Transplantation eingesetzt werden, aber auch dazu, Lebern von Nicht-Herzschlagenden Spendern zu nutzen.Normothermic extracorporeal liver perfusion (NELP) was studied as a means to pre-serve livers for transplantation and to reverse warm ischemic injury. For the first time we provide experimental evidence that successful transplantation after 4h of normo-thermic extracorporeal liver perfusion is possible and as reliable as 4h of cold preser-vation in University of Wisconsin solution. NELP preserves liver function completely and is capable of reversing 60 min of warm ischemic injury in non heart beating do-nors. 36 German Landrace pigs were transplanted in six groups. Group 1 animals were transplanted directly, group 2 animals after 4h of cold preservation with University of Wisconsin solution and group 3 animals following 4h of normothermic extracorporeal liver perfusion. Group 4 animals sustained 1h of warm ischemia before transplantation of the liver. In group 5 animals were transplanted following 1h of warm ischemia and 4h of cold preservation, and in group 6 after 1h of warm ischemia and 4h of normo-thermic extracorporeal liver perfusion. All animals receiving livers treated by normo-thermic extracorporeal liver perfusion survived without liver failure (group 3 and 6). In contrast, all animals in group 5 developed primary graft non-function within 24 h after transplantation. The technique of NELP holds the potential to keep a mammalian liver outside the body completely functional, possibly for longer than 4h. NELP can be used for liver preservation prior to transplantation or to utilise organs from non-heart-beating donors.
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Moreno, Noguer Francesc. "Multiple cue integration for robust tracking in dynamic environments: application to video relighting." Doctoral thesis, Universitat Politècnica de Catalunya, 2005. http://hdl.handle.net/10803/6191.
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L'anàlisi de moviment i seguiment d'objectes ha estat un dels pricipals focus d'atenció en la comunitat de visió per computador durant les dues darreres dècades. L'interès per aquesta àrea de recerca resideix en el seu ample ventall d'aplicabilitat, que s'extén des de tasques de navegació de vehicles autònoms i robots, fins a aplications en la indústria de l'entreteniment i realitat virtual.Tot i que s'han aconseguit resultats espectaculars en problemes específics, el seguiment d'objectes continua essent un problema obert, ja que els mètodes disponibles són propensos a ser sensibles a diversos factors i condicions no estacionàries de l'entorn, com ara moviments impredictibles de l'objecte a seguir, canvis suaus o abruptes de la il·luminació, proximitat d'objectes similars o fons confusos. Enfront aquests factors de confusió la integració de múltiples característiques ha demostrat que permet millorar la robustesa dels algoritmes de seguiment. En els darrers anys, degut a la creixent capacitat de càlcul dels ordinadors, hi ha hagut un significatiu increment en el disseny de complexes sistemes de seguiment que consideren simultàniament múltiples característiques de l'objecte. No obstant, la majoria d'aquests algoritmes estan basats en
heurístiques i regles ad-hoc formulades per aplications específiques, fent-ne impossible l'extrapolació a noves condicions de l'entorn.
En aquesta tesi proposem un marc probabilístic general per integrar el nombre de característiques de l'objecte que siguin necessàries, permetent que interactuin mútuament per tal d'estimar-ne el seu estat amb precisió, i per tant, estimar amb precisió la posició de l'objecte que s'està seguint. Aquest marc, s'utilitza posteriorment per dissenyar un algoritme de seguiment, que es valida en diverses seqüències de vídeo que contenen canvis abruptes de posició i il·luminació, camuflament de l'objecte i deformacions no rígides. Entre les característiques que s'han utilitzat per representar l'objecte, cal destacar la paramatrització robusta del color en un espai de color dependent de l'objecte, que permet distingir-lo del fons més clarament que altres espais de color típicament ulitzats al llarg de la literatura.
En la darrera part de la tesi dissenyem una tècnica per re-il·luminar tant escenes estàtiques com en moviment, de les que s'en desconeix la geometria. La re-il·luminació es realitza amb un mètode 'basat en imatges', on la generació de les images de l'escena sota noves condicions d'il·luminació s'aconsegueix a partir de combinacions lineals d'un conjunt d'imatges de referència pre-capturades, i que han estat generades il·luminant l'escena amb patrons de llum coneguts. Com que la posició i intensitat de les fonts d'il.luminació que formen aquests patrons de llum es pot controlar, és natural preguntar-nos: quina és la manera més òptima d'il·luminar una escena per tal de reduir el nombre d'imatges de referència? Demostrem que la millor manera d'il·luminar l'escena (és a dir, la que minimitza el nombre d'imatges de referència) no és utilitzant una seqüència de fonts d'il·luminació puntuals, com es fa generalment, sinó a través d'una seqüència de patrons de llum d'una base d'il·luminació depenent de l'objecte. És important destacar que quan es re-il·luminen seqüències de vídeo, les imatges successives s'han d'alinear respecte a un sistema de coordenades comú. Com que cada imatge ha estat generada per un patró de llum diferent il·uminant l'escena, es produiran canvis d'il·luminació bruscos entre imatges de referència consecutives. Sota aquestes circumstàncies, el mètode de seguiment proposat en aquesta tesi juga un paper fonamental. Finalment, presentem diversos resultats on re-il·luminem seqüències de vídeo reals d'objectes i cares d'actors en moviment. En cada cas, tot i que s'adquireix un únic vídeo, som capaços de re-il·luminar una i altra vegada, controlant la direcció de la llum, la seva intensitat, i el color.
Motion analysis and object tracking has been one of the principal focus of attention over the past two decades within the computer vision community. The interest of this research area lies in its wide range of applicability, extending from autonomous vehicle and robot navigation tasks, to entertainment and virtual reality applications.
Even though impressive results have been obtained in specific problems, object tracking is still an open problem, since available methods are prone to be sensitive to several artifacts and non-stationary environment conditions, such as unpredictable target movements, gradual or abrupt changes of illumination, proximity of similar objects or cluttered backgrounds. Multiple cue integration has been proved to enhance the robustness of the tracking algorithms in front of such disturbances. In recent years, due to the increasing power of the computers, there has been a significant interest in building complex tracking systems which simultaneously consider multiple cues. However, most of these algorithms are based on heuristics and ad-hoc rules formulated for specific applications, making impossible to extrapolate them to new environment conditions.
In this dissertation we propose a general probabilistic framework to integrate as many object features as necessary, permitting them to mutually interact in order to obtain a precise estimation of its state, and thus, a precise estimate of the target position. This framework is utilized to design a tracking algorithm, which is validated on several video sequences involving abrupt position and illumination changes, target camouflaging and non-rigid deformations. Among the utilized features to represent the target, it is important to point out the use of a robust parameterization of the target color in an object dependent colorspace which allows to distinguish the object from the background more clearly than other colorspaces commonly used in the literature.
In the last part of the dissertation, we design an approach for relighting static and moving scenes with unknown geometry. The relighting is performed through an -image-based' methodology, where the rendering under new lighting conditions is achieved by linear combinations of a set of pre-acquired reference images of the scene illuminated by known light patterns. Since the placement and brightness of the light sources composing such light patterns can be controlled, it is natural to ask: what is the optimal way to illuminate the scene to reduce the number of reference images that are needed? We show that the best way to light the scene (i.e., the way that minimizes the number of reference images) is not using a sequence of single, compact light sources as is most commonly done, but rather to use a sequence of lighting patterns as given by an object-dependent lighting basis. It is important to note that when relighting video sequences, consecutive images need to be aligned with respect to a common coordinate frame. However, since each frame is generated by a different light pattern illuminating the scene, abrupt illumination changes between consecutive reference images are produced. Under these circumstances, the tracking framework designed in this dissertation plays a central role. Finally, we present several relighting results on real video sequences of moving objects, moving faces, and scenes containing both. In each case, although a single video clip was captured, we are able to relight again and again, controlling the lighting direction, extent, and color.
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Tibbetts, Bollaert Helen. "CEO Characteristics and Firm Performance." Thesis, Lille 2, 2011. http://www.theses.fr/2011LIL20005.
Full textAbstract:
Dans les trois chapitres de cette thèse nous explorons le lien entre les performances des entreprises et les caractéristiques psychologiques des dirigeants. Dans un premier chapitre conceptuel, nous étudions les fondements théoriques des travaux en finance comportementale d'entreprise en analysant l'hubris et les concepts qui lui sont apparentés. Nous suggérons des pistes de recherche futures qui, pour certaines, sont mises en oeuvre dans les deux autres chapitres de ce travail. Dans le second chapitre, nous étudions l'impact du narcissisme des dirigeants acquéreurs et cibles sur les aspects privés d'un échantillon de fusions-acquisitions américaines. Nos résultats indiquent que desniveaux de narcissisme plus élevés chez les dirigeants acquéreurs sont associés à une plus forte probabilité que l'acquéreur initie l'opération et à une période plus courte entre l'initiation de l'opération et son annonce publique. Nos résultats suggèrent également que des niveaux de narcissisme plus élevés chez les dirigeants cibles sont positivement associés à la prime offerte et négativement associés aux rendements anormaux cumulés de l'acquéreur. Dans le troisième chapitre, nous analysons l'effet du leadership authentique du dirigeant sur les performances boursières etd'exploitation d'un échantillon d'entreprises du SBF 250. Nous collectons des données sur le leadership authentique par le biais de questionnaires. Nous analysons la différence entre les performances des entreprises en les affectant à trois portefeuilles selon le niveau de leadership authentique en utilisant l'analyse en trois facteurs de Fama et French. Nous ne trouvons aucun lien significatif entre le niveau de leadership authentique du dirigeant et la performance boursière. Dansles analyses des performances d'exploitation, nous trouvons un lien positif et significatif entre le niveau de leadership authentique et la rentabilité économique (ROA)We study the effect of CEO psychological characteristics on firm performance in three papers. We first consider the theoretical background to work in behavioral corporate finance in a conceptual paper analyzing hubris and related psychological concepts. In this paper we put forward ideas for future research, some of which we implement subsequent papers. In paper 2, we study the effect of acquirer and target CEO narcissism on the private aspects of the takeover process in a sample of US M&A deals. We find that higher levels of acquirer CEO narcissism are associated with a higher probability of deal initiation by the acquirer and with a shorter length of time between deal initiation and announcement. Concerning value effects, our results suggest that higher levels of target CEO narcissism are positively related to bid premium and negatively related to acquirer cumulative abnormal returns. In addition, the difference between acquirer and target CEO narcissism is a significant factor in explaining the different aspects of the takeover process. In the third paper, we analyze the effect of CEO authentic leadership on the market and operating performance of a sample of listed French firms. We collect data on CEO authentic leadership using questionnaires. We analyze the difference in performance of firms sorted into three portfolios according to the level of CEO authentic leadership using a Fama French three factor analysis. We fail to find a significant relationship between CEO authentic leadership and market performance. In the operating performance analyses, we find a positive association between CEO authentic leadership and ROA
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Delgado, Sanglas Jordi. "Contribución a la fundición selectiva por láser de pieza metálica mediante el estudio de propiedades mecánicas y de manufactura." Doctoral thesis, Universitat de Girona, 2013. http://hdl.handle.net/10803/117376.
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Selective laser melting process is an additive manufacturing technique that allows obtaining, from a 3D model, a physical model through a layer-by-layer manufacturing strategy. Several machines are commercially available, known as 3D printers. Recently, technology improvements have allowed the use of metallic materials; however, the amount of materials available is low due to the difficulty to find adequate manufacturing parameters. The thesis proposes a methodology, using an inclined plane, to set the minimum energy density to melt a continuous track, the first step of the melting process. Different process parameters from several commercials machines have been used to evaluate dimensional and mechanical properties. Replicas of traditional products have been fabricated using additive process and they have been compared. Finally, a protocol to use a selective laser melting process to reconstruct a personalized jaw prosthesis has been shownLa fusió selectiva per làser és un procés de fabricació additiva que permet obtenir, d'un disseny en 3D, un model físic de forma ràpida i a través d'una estratègia de fabricació capa a capa. Existeixen diferents màquines comercials anomenades impressores 3D. Actualment, les millores tècniques desenvolupades han permès la utilització de materials metàl·lics, no obstant, la quantitat de materials que es poden utilitzar és baix degut a la dificultat per trobar els paràmetres de fabricació més adequats. La tesis proposa una metodologia, a través d’un pla inclinat, que permet definir la densitat d’energia mínima per fondre un cordó continu, el primer pas del procés de fusió làser. Diferents paràmetres de varies màquina comercials s'han utilitzat per avaluar variables dimensionals i mecàniques. S'han comparat rèpliques fabricades mitjançant processos tradicionals i processos additius. Finalment, s'ha realitzat un protocol per a reconstruir una mandíbula personalitzada utilitzant la fusió selectiva per làser
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Wang, Shu-Lin, and 王書麟. "A Novel Fusion Method for MR and PET Images." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/j7dq73.
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碩士國立中興大學
資訊科學與工程學系所
101
Due to the development of nuclear medicine, extensive applications of medical imaging technology enhance the accuracy of diagnosis. The goal of this thesis is to develop a new image fusion approach to combine the structural information of Magnetic Resonance Imaging (MRI) and the color information of Positron Emission Tomography (PET) in one image. A new method is designed to extract and reinforce the details of a fused image. The method has two phases: image fusion and reinforcement. In the first phase, the gray-level intensity is obtained through the IHS transform of PET images. With appropriate scales of decomposition and orientations, Log-Gabor wavelet transform is performed to the gray-level intensity of PET and the image of MRI. After the high frequency components of the previous two are fused, inverse Log-Gabor wavelet transform is applied to the result and the low frequency components of the gray-level intensity of PET to get the new gray-level intensity. In the second phase, the Otsu’s method is used to find the target position of the reinforced details in MRI, and then compared the information with both PET''s and MRI''s gray-level intensity. After the replacement of the target position''s gray-level intensity, inverse IHS transform is performed to the reinforced gray-level intensity and the other two components of the PET images to obtain the fused image. The experimental results show that the color fused images have less distortion with the proposed method; moreover, the amount of MRI''s information structure is more abundant, and can be clearly displayed in the fusion image.
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Wang, Woei Fuh, and 王瑋馥. "Image registration and fusion of PET and MRI images using neural network." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/64541420437715654749.
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碩士國立陽明大學
放射醫學科學研究所
90
Multi modality image registration and fusion is more and more important nowadays. Good image quality can provide more accurate patient information, which can then be used for better clinical decision making. X-ray computed tomography (CT) and magnetic resonance imaging (MRI) images are anatomical imaging with high spatial resolutions. On the other hand, although positron emission tomography (PET) and single photon emission computed tomography (SPECT) can provide physiological information, their spatial resolutions are too poor to provide clear anatomical information. Thus, it is very important to combine images from multi-modality scanning such that the resulting image can provide both physiological and anatomical information with high spatial resolution for use in clinical diagnosis and therapy. In order to generate an image from different-modality images, we used multi-layer backpropogation and conjugate gradient backpropogation neural network model to train PET and MRI images. We used Matlab and Borland C++ Builder to implement the network training frame and found out the optimal training model for accurate image registration. Further, we evaluated the accuracy of the image registration via phantom images. In our study, we found that it will be better if we use the single layer network with linear activation function. The registration errors are between 1-3 pixels for computer generated templates. In phantom studies, the registration errors are less than 5mm, and the accuracy of image registration is too worse to use if angle of rotation mismatch is more than 150. Finally, we have used Borland C++ Builder to implement an user-friendly window-based interface for image registration and fusion.
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SU, HSIAO-HAN, and 蘇筱涵. "Between Chinese Pen/Ink and Western Composition: Wu GuanZhong’s Paintings as Cultural Fusion." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/q8b8g3.
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碩士國立新竹教育大學
藝術教育與創作碩士班
104
This study is focused on Wu Guanzhong’s chinese ink painting, using the achievement of chinese and western fusion as an example, to explore the possibility of contemporary chinese ink painting innovation. Theoretical research and style analysis methods are used. Starting from the changing of traditional chinese ink painting and aesthetic foundation, then organizing Wu Guanzhong’s art theory, analyzing his modern chinese ink paintings, and then discussing on his artistic achievements and contributions. Artistic conception, pen/ink, mood (yi jing) and some literati characteristic are important of traditional ink painting. Wu believes that ink is one form of painting tools or instruments and modern creative works should not be limited by traditional technique of painting, substantially similar to Shi Tao's view that 'pen/Ink should be innovated with the times'and 'whole painting as one stroke principle is established by myself'. In addition, Wu still paid attentions to form and inner beauty of art. Beauty is showed in painting via form and the highest level of abstract beauty is the pictorial mood. However, the mediums of usage are different, and there are also different understandings in form and mood between chinese and western painting systems. Wu found that it is profitable to nourish both chinese and western art by using oil and ink for an interactive creating, merging his traditional ink painting technique and that of drawing studied in France. Therefore, he regards 'assimilation of oil painting' and 'ink modernization' as two touchstones making two aesthetic systems communicate with each other. Wu's ink painting practice includes the chinese pen as a tool, supplemented by the formal schema of western paintings, obtaining chinese and western intermediation and thereby its eventual fruitful results.
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Hsiao, Yu-Lin, and 蕭育麟. "Performance Evaluation of The Section of 3D Reconstruction Based on Different PET/CT Image Fusion Sequence." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/6fv8v6.
Full textAbstract:
碩士國立臺北科技大學
自動化科技研究所
101
In recent years, positron emission tomography imaging (PET) widely used in medical examinations, such as cancer detection. Computed tomography (CT) for the anatomic images, the main function for the observation of human structures, such as bones, so the spatial information is more accurate. Therefore, PET / CT fusion images can be observed metabolic information, they can get a more accurate spatial information.People have to construct 3D models in the first place when they try to examine images from different angles. Once a cross-section which we want to inspect has been revealed, it can be observed from any angles. However, a issue people encounter in above-mentioned procedures is that they have to either process images fusion at the beginning and then reconstruct the 3D models with these images to generate section or rebuilt the 3D models with these images and fuse section images as the second step. The main objective of this research is to discriminate the divergences and merits between two types of procedures.This research discovers that two different procedures will exactly bring about dissimilar types of images. Therefore, this research particularly aims at the analysis of two images and evaluates the extent of fringe and remaining information. We calculates entropy and standard deviation of the images. Nevertheless, finding section on 3D models first and fusing images secondly will generate the images which retain more information.
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Barnes, Michael. "The 3He(d,p)4He nuclear fusion reaction as a source of mega-voltage protons for the production of fluorine-18 for PET applications." 2009. http://hdl.handle.net/1959.13/38557.
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Masters Research - Master of Philosophy (Physics)Fluoro-deoxyglucose (FDG) labeled with fluorine-18 is commonly used in positron emission tomography (PET) imaging. PET imaging is a powerful tool used primarily in the diagnosis and management of cancer. The growth of PET has been limited partly by the difficulties associated in producing fluorine-18. This project involves a theoretical investigation of a novel method of producing fluorine-18 utilising proton generation via the 3He(d,p)4He nuclear reaction. Currently the most common method of producing fluorine-18 for PET is with a medical cyclotron that accelerates protons to mega-voltage energies. These protons are then directed onto a target rich in oxygen-18. This initiates the 18O(p,n)18F reaction to produce fluorine-18. The 3He(d,p)4He reaction, utilized for the present study, has a Q-value of 18.35 MeV and this results in protons being produced at energies similar to that produced in a medical cyclotron. This reaction was investigated as an alternative proton source for the 18O(p,n)18F reaction. The expected advantage of this method over the cyclotron is that particles need only be accelerated to keV energies rather than the tens of MeV that a medical cyclotron accelerates protons to. This is expected to significantly reduce the cost and associated size of the system. Two systems based on the 3He(d,p)4He reaction were designed and calculations were performed to determine the respective yields of fluorine-18. The first system involved separate targets for the 3He(d,p)4He and 18O(p,n)18F reactions. Helium-3 ions are initially fired onto a deuterated plastic target. A heavy-water (H2O18) target is placed immediately behind this plastic target to absorb mega-voltage protons produced by the reaction 3He(d,p)4He in the plastic. The second system involved a single, super heavy water (D2O18) target onto which helium-3 is fired so that both the 3He(d,p)4He and 18O(p,n)18F reactions can occur concurrently in the one target. The input parameters of energy and beam current for the helium-3 beam required for the 3He(d,p)4He reaction were selected on the basis of the performance of currently available ion sources and in particular the saddle-field ion source. Practical considerations such as radiation safety, target degradation and lifetime and ultra high vacuum (UHV) issues were also investigated to further determine the feasibility of the two systems. With the beam current and energy at the extreme limits of the saddle-field ion source it was calculated that insufficient fluorine-18 could be produced daily to supply a PET facility with FDG. It was also found that the high helium-3 beam currents and energy required to produce significant amounts of fluorine-18 resulted in prohibitive temperature rises in the targets that would likely result in target vaporization.
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Chiang, Jen-Hong, and 江仁宏. "Face Recognition Using Fusion Multiple Features Extraction Based on Fourier-Mellin Approach for Single Example Image per Person." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/38795096217383392412.
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博士元智大學
工業工程與管理學系
99
Despite the constantly change of human face pose, illumination, expression, and occultation, one major problem of the face recognition technique arises from the difficulties of collecting samples. Under this limited condition, the database at hand is too weak to offer sufficient distinctive features to the system, and of course, the performance drop is expected. This problem is called the single example image per person problem. Single example image per person problem has received significant attention during the past years. Researchers have proposed sample-strengthen method, sample-expansion method, and generic learning framework, etc, which mostly aim to expand each person’s face image sample by using computer technique to create several combining images based on the original one. Therefore, the single example image per person problem simply becomes multiple images per person recognition problem. However, these methods result in enlarging the calculation volume and requiring bigger storage space. It also needs to be retrained once a new person is put into system. These problems make it extremely difficult to popularize these methods. In this paper, we try to exclude training and to extract directly from the Orthogonal Fourier-Mellin moments (OFMM), which has constructed a set of similarity invariants. The approach is to normalize the scale and translation, lower the dimension through wavelet transform to decrease the calculation volume of orthogonal moments, and this could make human face recognition more specific in pose. Further, to effectively reduce the recognition errors caused by illumination change, the construction of a set of similarity invariants using the hybrid Taylor-ATMT are studied. Human face expression change and partial occultation could be reduced by projecting it to wavelet space to lower the dimension, and then to compare the nearest distance of those and classify categories, and which also results positive recognition rate. Since hybrid Taylor-ATMT and Orthogonal Fourier-Mellin moments are complementary and the similarity invarants using the hybrid Taylor-ATMT based on the vertical gradient vector has the robustness to illumination, we attempt to improve the face recognition performance within a combination of frequency features, moment features, and gradient vector features framework based on the Fourier-Mellin transform approach. The fusion of according to the Bayesian theory will be applied to three features above. Experiments are implemented on YALE and ORL face databases to demonstrate the efficient of proposed approach. The experimental results show that the average recognition accuracy rates are 74% and 70% of our proposed method which are higher than those of previous methods.
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Heitmann, Britta [Verfasser]. "Bedeutung der Positronenemissionstomographie (PET) mit dem Tracer-11C-Acetat in der morphologischen Abklärung des biochemischen Prostatakarzinomrezidivs : Stellenwert der Fusion der PET mit CT-MRT / vorgelegt von Britta Heitmann." 2011. http://d-nb.info/1012921514/34.
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Pröschild, Annette [Verfasser]. "Anato-metabolische Bildgebung der postischämischen Mitralinsuffizienz : zweidimensionale Image-Fusion kardialer 18FDG-PET und EBT-Schnittbilder ; ein neues Konzept / vorgelegt von Annette Pröschild." 2001. http://d-nb.info/965210677/34.
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"Un model d'incertesa fitada per a la propagació i fusió d'informació geomètrica incerta." Universitat Politècnica de Catalunya, 1996. http://www.tesisenxarxa.net/TDX-0722109-100810/.
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Sá, Diniz Araújo de. "Estudo da fusão de imagem médica PET/TAC auxiliada por câmara kinect V2." Master's thesis, 2016. http://hdl.handle.net/10316/33069.
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