Tesi: "Region of interest"

1

Budihal, Prasad Adhokshaja Achar. "Region of Interest Based Compression of Grayscale Images". Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/5842.

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Image compression based on Region of Interest (ROI) has been one of the hot topics of interest in image processing. There is not a single widely accepted method for detecting the ROI automatically form an image. To reduce the transmission bandwidth and storage space requirements of gray scale images, an algorithm is suggested for detecting the ROI automatically based on Tsallis entropy method. Tsallis entropy method is used to segment the image into two segments, the ROI and the background. These two segments can then be compressed at different rates, to avoid losing information in the ROI while achieving a good compression. Different approaches of compression based on wavelets and use of various compression methods are also discussed.

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2

Gopalan, Ramya. "Exploiting Region Of Interest For Improved Video Coding". The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1250622014.

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3

Sinharoy, Indranil. "Region-of-interest estimation for multi-aperture imaging systems". Ann Arbor, Mich. : ProQuest, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1440435.

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Thesis (M.S. in Electrical Engineering)--S.M.U., 2007.
Title from PDF title page (viewed Mar. 18, 2008). Source: Masters Abstracts International, Volume: 45-03, page: 1615. Adviser: Scott C. Douglas. Includes bibliographical references.

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4

Sassi, Salem Ahmed. "Region of interest imaging technique : a novel approach to increase image contrast within the region of interest and reduce patient dose in fluoroscopy". Thesis, St George's, University of London, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264975.

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5

Karlsson, Linda S. "Spatio-Temporal Pre-Processing Methods for Region-of-Interest Video Coding". Licentiate thesis, Mid Sweden University, Department of Information Technology and Media, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-51.

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In video transmission at low bit rates the challenge is to compress the video with a minimal reduction of the percieved quality. The compression can be adapted to knowledge of which regions in the video sequence are of most interest to the viewer. Region of interest (ROI) video coding uses this information to control the allocation of bits to the background and the ROI. The aim is to increase the quality in the ROI at the expense of the quality in the background. In order for this to occur the typical content of an ROI for a particular application is firstly determined and the actual detection is performed based on this information. The allocation of bits can then be controlled based on the result of the detection.

In this licenciate thesis existing methods to control bit allocation in ROI video coding are investigated. In particular pre-processing methods that are applied independently of the codec or standard. This makes it possible to apply the method directly to the video sequence without modifications to the codec. Three filters are proposed in this thesis based on previous approaches. The spatial filter that only modifies the background within a single frame and the temporal filter that uses information from the previous frame. These two filters are also combined into a spatio-temporal filter. The abilities of these filters to reduce the number of bits necessary to encode the background and to successfully re-allocate these to the ROI are investigated. In addition the computational compexities of the algorithms are analysed.

The theoretical analysis is verified by quantitative tests. These include measuring the quality using both the PSNR of the ROI and the border of the background, as well as subjective tests with human test subjects and an analysis of motion vector statistics.

The qualitative analysis shows that the spatio-temporal filter has a better coding efficiency than the other filters and it successfully re-allocates the bits from the foreground to the background. The spatio-temporal filter gives an improvement in average PSNR in the ROI of more than 1.32 dB or a reduction in bitrate of 31 % compared to the encoding of the original sequence. This result is similar to or slightly better than the spatial filter. However, the spatio-temporal filter has a better performance, since its computational complexity is lower than that of the spatial filter.

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6

Sundstedt, Karin Veronica. "Rendering and validation of high-fidelity graphics using region-of-interest". Thesis, University of Bristol, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.440273.

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7

Rafiee, Gholamreza. "Automatic region-of-interest extraction in low depth-of-field images". Thesis, University of Newcastle upon Tyne, 2013. http://hdl.handle.net/10443/2194.

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Automatic extraction of focused regions from images with low depth-of-field (DOF) is a problem without an efficient solution yet. The capability of extracting focused regions can help to bridge the semantic gap by integrating image regions which are meaningfully relevant and generally do not exhibit uniform visual characteristics. There exist two main difficulties for extracting focused regions from low DOF images using high-frequency based techniques: computational complexity and performance. A novel unsupervised segmentation approach based on ensemble clustering is proposed to extract the focused regions from low DOF images in two stages. The first stage is to cluster image blocks in a joint contrast-energy feature space into three constituent groups. To achieve this, we make use of a normal mixture-based model along with standard expectation-maximization (EM) algorithm at two consecutive levels of block size. To avoid the common problem of local optima experienced in many models, an ensemble EM clustering algorithm is proposed. As a result, relevant blocks, i.e., block-based region-of-interest (ROI), closely conforming to image objects are extracted. In stage two, two different approaches have been developed to extract pixel-based ROI. In the first approach, a binary saliency map is constructed from the relevant blocks at the pixel level, which is based on difference of Gaussian (DOG) and binarization methods. Then, a set of morphological operations is employed to create the pixel-based ROI from the map. Experimental results demonstrate that the proposed approach achieves an average segmentation performance of 91.3% and is computationally 3 times faster than the best existing approach. In the second approach, a minimal graph cut is constructed by using the max-flow method and also by using object/background seeds provided by the ensemble clustering algorithm. Experimental results demonstrate an average segmentation performance of 91.7% and approximately 50% reduction of the average computational time by the proposed colour based approach compared with existing unsupervised approaches.

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8

Lee, Shuk-ping, e 李淑冰. "Social stability and public policy: the role of special interest groups in Macao". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B3642433X.

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9

Rao, Sira. "Elastic Algorithms for Region of Interest Video Compression, with Application to Mobile Telehealth". Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/19881.

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Video is the most demanding modality from the viewpoints of bandwidth, computational complexity, and resolution. Thus, there has been limited progress in the field of mobile video technology. In the research, the focus is on elastic wireless video technology, and its adaptation to diagnostic application requirements in real-time clinical assessment. It is important and timely to apply wireless video technology to real-time remote diagnosis of emergent medical events. This premise comes from initial successes in telehealth based on wired networks. The enablement of mobility (for the physician and/or the patient) by wireless communication will be a next major step, but this advance will depend on definitive and compelling demonstrations of reliability. Thus, an important goal of the research is to develop a complete methodology that will be embraced by physicians. Acute pediatric asthma has been identified as a domain where this new capability will be highly welcome. The research uses flexible and interactive algorithms for Region-of-Interest (ROI) processing. ROI processing is a useful approach to achieve the optimal balance in the quality-bandwidth tradeoff characteristic of visual communication services. The notion of ROI has been traditionally used mostly for foreground-background separation in scene rendering and manipulation, and only more recently for variably quality compression. Even when the latter goal is considered, quality criteria have been ad-hoc and at best useful for video conferencing, given that the medical domain has its own fidelity criteria. The research thus focuses on the design of an elastic ROI-based compression paradigm with medical diagnosis as a central criterion. The research describes the methodology to achieve elasticity through rate control algorithms at the encoder. An elastic non-parametric approach is proposed that uses a priori user-specified video quality information, quantifies this information, and incorporates this into the encoder in the form of region-quality mappings. This method is compared to a parametric bit allocation approach that is based on region-features and a set of tuning weights. A number of videos of actual patients were filmed and used as the video database for the developed algorithms. In testing the elastic non-parametric and parametric algorithms, both objective measures in the form of Peak Signal to Noise Ratio (PSNR), and subjective evaluations were used. Thus, in this work, the focus is on domain relevance of the algorithms developed, as opposed to network related issues such as packet losses. This is justified in that these may have broader value with other applications, and continuation of this work will include realistic network conditions. To summarize, the research shows the usefulness of ROI processing as a means of achieving a gain (in a bits per pixel sense) over uniform compression at the same bitrate. It also shows how quantifying a notion of functionally lossless video quality diagnostically lossless video quality in a video-based telehealth system, in a bits per pixel sense is useful from an applications and bitrate perspective. Finally, a combination of these two concepts is advantageous i.e. diagnostically lossless ROI video quality is achievable over bitrate limited channels.

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10

Liljekvist, Pontus Holmertz, e Andreas Zsigmond. "Real-Time Tessellation A Region of Interest Based Technique Suited for Game Applications". Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-2081.

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While the games industry grows, the need for visually appealing graphics increase. This drives the demand for new hardware and the development of new techniques forward. With the latest generation of 3D graphic APIs the new rendering pipeline technique tessellation was announced. With each generation of games getting more advanced, the demand for highly detailed models increase. This leads to a higher workload for the GPU. The purpose of this thesis is to research the fi eld of tessellation and develop a prototype to optimize the tessellation pipeline. The prototype is designed to help reduce the number of generated triangles by dividing the mesh into regions, each region with its own tessellation factor. The prototype implementation supports both manual and automatic generation of these regions. A new fi le format was developed to support the region data. The implementation was split into three parts; one Python based Maya plug-in used for preparing the model for exporting, one exporter for Maya that generated the output fi le, and one viewer application capable of rendering the resulting mesh. The geometry output of the proposed technique was evaluated by comparing it to uniformly tessellated reference mesh geometry. Measurements show that the proposed technique is capable of reducing the face count with minor or maintained correlation to the reference geometry.
Medans spelindustrin växer ökar behovet av visuellt tilltalande grafik. Detta driver utvecklingen av hårdvara och nya tekniker framåt. Med den senaste generationens 3D grafik API kom renderingssteget tesselering. Eftersom varje generation av spel blir mer avancerat ökar efterfrågan på detaljerade modeller. Detta leder till en högre arbetsbörda för GPUn. Syftet med denna avhandling är att undersöka tesselering och utveckla en prototyp för att optimera tesseleringspipelinen. Prototypen är utformad för att hjälpa till att minska antalet genererade trianglar genom att dela upp figuren i regioner, varje region med egen tesseleringsfaktor. Prototypen stödjer både manuell och automatisk generering av dessa regioner, ett nytt filformat utvecklades för att stödja dessa. Prototypen delades upp i tre delar, ett Python baserat Maya plug-in som används för att förbereda modellen för export, en Maya exportör som genererar filerna, och ett visningsprogram som kan rendera den färdiga figuren. Figuren från den föreslagna tekniken utvärderades genom att jämföra den med motsvarande figur med universal tesseleringsfaktor. Mätningar visar att den föreslagna tekniken klarar att reducera antalet trianglar med låg felmarginal.

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11

Elsayed, Ashraf. "Region of interest based image classification : a study in MRI brain scan categorization". Thesis, University of Liverpool, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.569588.

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This thesis describes research work undertaken in the field of image mining. More specifically, the research work is directed at image classification according to the nature of a particular Region Of Interest (ROI) that appears across a given image set. Four approaches are described in the context of the classification of medical images. The first is founded on the extraction of a ROI signature using the Hough transform, but using a polygonal approximation of the ROI boundary. The second approach is founded on a weighted subgraph mining technique whereby the ROI is represented using a quad-tree structure which allows the application of a weighted subgraph mining technique to identify feature vectors representing these ROIs; these can then be used as the foundation with which to build a classifier. The third uses an efficient mechanism for determining Zernike moments as a feature extractor, which are then translated into feature vectors to which a classification process can be applied. The fourth is founded on a time series analysis technique whereby the ROI is represented as a pseudo time series which can then be used as the foundation for a Case Based Reasoner. The presented evaluation is directed at MRI brain scan data where the classification is focused on the corpus callosum, a distinctive ROI in such data. For evaluation purposes three scenarios are considered: distinguishing between musicians and non-musicians, left handedness and right handedness, and epilepsy patient screening.

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12

Eisenmann, Jonathan A. "Interactive Evolutionary Design with Region-of-Interest Selection for Spatiotemporal Ideation & Generation". The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1405610355.

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13

Sormain, Rémi. "Offline H.264 encoding method for omnidirectional videos with empirical region-of-interest". Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-211518.

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Panoramic virtual reality is an emerging technology that has recently gained the attention of both the research community and regular consumers. It allows the users to immerse themselves in omnidirectional videos with the help of a virtual reality headset : thanks to an increasing amount of affordable head-mounted-displays, any recent smartphone can offer a decent panoramic virtual reality experience. However since omnidirectional videos are videos with a large field-of-view that covers the entire sphere around the camera, they require large resolutions and thus high bitrates. This master degree project conducted at RE’FLEKT GmbH is an exploratory work that seeks to reduce the panoramic video bitrate. Because of the nature of omnidirectional videos, the user can only see a subpart of each video frame, and thus some zones of the video can attract more attention than others. The purpose of this study is to introduce the concept of region-of-interest encoding in panoramic VR. The main contribution is a method to encode panoramic videos in an H.264 video format stream with a space-variant level of details depending on the zones that attract the most the viewers’ interest. First, the region-of-interest are detected through a head-tracking module combined with a Gaussian attention model. Then, the reference video is encoded with the open source x264 encoder, with a quantization step adjusted to the region-of-interest information. The International Telecommunications Union standard subjective tests show that this method can perform better than classic H.264 encoding only in specific cases.
Panoramisk virtuell verklighet (VR) är en kommande teknik som nyligen har mött intresse från forskarsamhället och vanliga konsumenter. Det gör det möjligt för användarna att fördjupa sig i videor upptagna från flera riktningar, med hjälp av ett VR-headset : tack vare ett växande antal billiga och huvudburna bildskärmar, erbjuder alla nya smarttelefoner en passande panoramisk VR-erfarenhet. Men på grund av den breda synvinkeln i flerriktade media behöver videor med 360 graders synfält stor upplösning och därför höga bithastigheter. Detta masterexamensarbete som utförts på RE’FLEKT GmbH är ett utforskande arbete som strävar efter att reducera panoramabildens bithastighet. I flerriktade videoklipp kan användaren bara se en del av varje bildruta, härigenom får somliga zoner mer uppmärksamhet än andra. Syftet med denna studie är att introducera begreppet region-av-intresse (ROI) kodning i panoramisk VR. Huvudbidraget är en metod för att koda panoramisk video i en H.264-ström med en varierande nivå av detaljer som beror på de zoner som får mest av tittarnas intresse. Först detekteras ROI genom en huvudspårningsmodul kombinerad med en gaussisk uppmärksamhetsmodell. Därefter kodas referensvideoen med x264-kodaren (öppen källkod) med hjälp av ROI-informationen. ITU-standardens subjektiva test visar att den här metoden kan fungera bättre än klassisk H.264-kodning i enskilda fall.

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14

Chihaoui, Takwa. "Système d'identification de personnes basé sur la rétine". Thesis, Paris Est, 2018. http://www.theses.fr/2018PESC1145/document.

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Notre travail s’inscrit dans le cadre de la biométrie par la rétine. La rétine est la couche sensorielle de l’œil, elle présente une texture riche et unique même chez les jumeaux. Ses propriétés ont fait de la biométrie par la rétine un axe de recherche actif. En effet, de nombreuses méthodes ont été proposées pour les différentes étapes de la méthode biométrique allant du prétraitement de l’image rétinienne à son analyse, en passant par sa caractérisation, afin d’identifier et authentifier un individu. Nous nous intéressons dans ces travaux de thèse, à l’étude, la conception, le développement et l’évaluation d’une nouvelle méthode biométrique basée sur la rétine. Notre première contribution réside dans la conception d’une méthode d’analyse d’image rétinienne saine et pathologique, suivie d’une sélection d’une région d’intérêt autour du disque optique. Cette méthode améliore la qualité de l’image rétinienne et extrait une région d’intérêt la plus stable de la rétine afin de maintenir une densité d’information satisfaisante, pour assurer une meilleure qualité de reconnaissance. Notre deuxième contribution porte sur la proposition d’une nouvelle méthode d’extraction de caractéristiques locales basée sur le descripteur standard SIFT. Elle applique une nouvelle approche reposant sur la suppression des points d’intérêt non informatifs extraits par le descripteur standard SIFT. Cette nouvelle méthode d’extraction des caractéristiques locales réduit le nombre des points d’intérêt redondants tout en maintenant la qualité de la description. Nous avons validé, la méthode biométrique proposée sur différentes bases comprenant des images saines et pathologiques. Les résultats obtenus montrent des performances encourageantes. Ces résultats indiquent, que la méthode que nous avons proposée, localise correctement la région d’intérêt rétinienne. En mode identification, un taux d’identification correcte d’environ 99.8% est atteint. En mode vérification, nous avons obtenu un taux FRR de 0.12% quant aux taux FAR et EER (erreur), ils sont de 0%. L’étude comparative a montré que notre méthode est plus discriminative que d’autres méthodes de l’état de l’art, notamment celles basées sur la segmentation et l’extraction de l’arbre vasculaire
Our work is part of the retina biometrics. The retina is the sensory layer of the eye; it has a rich and unique texture even in twins. Its properties have made the retina biometrics an active research area. Indeed, numerous methods have been proposed for the various stages of the biometric method, from pretreatment of the retinal image to its analysis, through its characterization, in order to identify and authenticate an individual. We are interested in this work in these thesis works, the study, design, development and evaluation of a new biometric method based on the retina. This thesis presents our contributions for each stage of the proposed biometric method. Our first contribution lies in the proposition of a healthy and pathological retinal image analysis method, followed by a selection of a region of interest around the optical disc. This method improves the quality of the retinal image and extracts a more stable region of interest from the retina to maintain a satisfactory information density, to ensure a better quality of recognition. Our second contribution consists in proposing a new method for extracting local characteristics based on the standard SIFT descriptor. It applies a new method based on the removal of non-informative points of interest extracted by the standard SIFT descriptor. This new method of extracting local features reduces the number of redundant points of interest while maintaining the quality of the description. We validated, the proposed biometric method on different bases including healthy and pathological images. This biometric method has yielded encouraging results on healthy and pathological retinal images. The results obtained show encouraging performances. These results indicate that the method we have proposed, correctly locates the retinal region of interest. In identification mode, a correct identification rate of approximately 99.8% is reached. In verification mode, we obtained 0.12% as FRR error rate and 0% for the FAR and EER error rates. The comparative study showed that our method is more discriminative than other state-of-the-art methods, especially those based on segmentation and extraction of the vascular tree

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15

Carmona, Cañabate Susana. "Neuroanatomy of attention deficit hiperactivity disorder: voxel-based morphometry and region of interest approaches". Doctoral thesis, Universitat Autònoma de Barcelona, 2008. http://hdl.handle.net/10803/5581.

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El trastorno por déficit de atención e hiperactividad (TDAH) es un trastorno del neurodesarrollo caracterizado por síntomas de inatención, hiperactividad e impulsividad. Los modelos clásicos acerca de la neuroanatomía del trastorno apuntan a alteraciones en los circuitos fronto-estriado-cerebelares. Los estudios de neuroimagen estructural apoyan parcialmente estos modelos. Sin embargo, casi todos estos estudios se basan en el análisis de regiones seleccionadas a priori (procedimiento que se conoce como ROI, acrónimo inglés de regiones de interés: "region of interest"). Estudios más recientes basados en aproximaciones globales apuntan a que las alteraciones estructurales no se limitan a los circuitos fronto-estriado-cerebelares, sino que también afectan las regiones temporales, parietales y cinguladas.
El objetivo de la presente tesis es el de redefinir y aplicar dos métodos de análisis estructural complementarios para identificar los circuitos cerebrales alterados en el TDAH así como para relacionar dichos circuitos con los diferentes subtipos clínicos. Para tal fin, presentaremos y discutiremos dos estudios de resonancia magnética estructural (Carmona et al. 2005; Tremols et al. 2008). Estos dos estudios representan una novedad y mejora de estudios de TDAH previos, por dos razones principales: a) la aplicación por primera vez un estudios basado en la morfometría de vóxeles para comparar el cerebro de niños con TDAH con el cerebro de niños controles no relacionados familiarmente; b) el diseño e implementación de un nuevo método, fácil de aplicar, de segmentación manual del núcleo caudado.
Los resultados confirman los datos obtenidos en estudios previos acerca de menor volumen cerebral en niños con TDAH, y localizan esta reducción en determinadas regiones de sustancia gris. A parte de confirmar las alteraciones fronto-estriado-cerebelares hayamos reducciones en áreas parietales, cingulares y temporales. En concreto observamos decrementos volumétricos de sustancia gris en la corteza frontal inferior, el estriado dorsal, la corteza parietal inferior y la corteza cingulada posterior, regiones clásicamente relacionadas con problemas de inhibición, deficits de memoria de trabajo y alteraciones en tareas de atención visuoespacial, respectivamente. También observamos reducciones volumétricas en áreas típicamente emocionales, como la corteza orbitofrontal, el estriado ventral y las estructurales temporales mediales deficits que podrían explicar las disfunciones motivacionales así como las alteraciones en el procesamiento del refuerzo. Curiosamente, las reducciones de sustancia gris en áreas relacionadas con el procesamiento emocional son más pronunciadas en el subtipo hiperactivo-impulsivo, algo menos en el subtipo combinado y casi inexistentes en el subtipo inatento. Esta diferente afectación en función de los subtipos va en la línea de teorías neuroanatómicas actuales acerca del TDAH (Castellanos and Tannock 2002). También observamos déficits de sustancia gris en áreas sensorio-motoras (específicamente en la corteza perirrolándica y el área motora suplementaria), y en el cerebelo. Por un lado, los déficits en áreas sensorio-motoras probablemente reflejan los problemas de psicomotricidad fina que presentan muchos de los niños con TDAH. Sin embargo, el hecho de que estas reducciones sean especialmente prominentes en los subtipos combinado e inatento, sugieren la posibilidad de que estas alteraciones estén especialmente relacionadas con los déficits atencionales. En base a esto, hipotetizamos que las alteraciones en estas regiones producirían un déficit para integrar y actualizar la información procedente del mundo exterior y, a su vez darían lugar a un sesgo a favor del procesamiento de los estados internos resultando en inatención. Por otro lado, las reducciones cerebelares (extensamente observadas en la literatura del TDAH) parecen están relacionadas con los déficits cognitivos, los afectivos y los emocionales. Creemos que la implicación del cerebelo en estas disfunciones estaría vehiculada por el papel de esta estructural como moduladora del flujo de información entre los circuitos fronto-estriatales. Finalmente nuestros hallazgos son los primeros en demostrar alteraciones diferenciales en la cabeza y el cuerpo del núcleo caudado en el TDAH. Esta desigual implicación de las diferentes partes del núcleo caudado explicaría en parte la heterogeneidad de los estudios previos.
Como conclusión, las reducciones volumétricas de sustancia gris en áreas cognitivas y emocionales apoyan la implicación de disfunciones en los circuitos fronto-estriatales llamados cool (cognitivos) y hot (emocionales) respectivamente. Hasta la fecha este es el primer estudio neuroanatómico que apoya la existencia de disfunciones tanto cognitvas como emocionales en niños con TDAH. Nuestros hallazgos constituyen la primera evidencia neuroanatómica a favor de los modelos de doble ruta porpuestos por Sonuga-Barke (Sonuga- Barke 2002; Sonuga-Barke 2003).
REFERENCIAS:
1. Tremols V, Bielsa A, Soliva JC, Raheb C, Carmona S, Tomas J, et al. (2008): Differential abnormalities of the head and body of the caudate nucleus in attention deficit-hyperactivity disorder. Psychiatry Res. 163:270-278.
2. Carmona S, Vilarroya O, Bielsa A, Tremols V, Soliva JC, Rovira M, et al. (2005): Global and regional gray matter reductions in ADHD: a voxel-based morphometric study. Neurosci Lett. 389:88-93.
3. Castellanos FX, Tannock R (2002): Neuroscience of attention-deficit/hyperactivity disorder: the search for endophenotypes. Nat Rev Neurosci. 3:617-628.
4. Sonuga-Barke EJ (2003): The dual pathway model of AD/HD: an elaboration of neuro-developmental characteristics. Neurosci Biobehav Rev. 27:593-604.
5. Sonuga-Barke EJ (2002): Psychological heterogeneity in AD/HD--a dual pathway model of behaviour and cognition. Behav Brain Res. 130:29-36.
Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disease characterized by symptoms of inattention, hyperactivity and impulsivity. Data from different studies point to ADHD abnormalities in fronto-striatal circuits. Structural neuroimaging studies partially support fronto-striatal abnormalities and suggest an important role of the cerebellum. However, nearly all these studies are based on the analysis of apriori selected regions of interest (known as ROI approaches). Recent studies, using more global approaches, found that ADHD structural abnormalities were not limited to fronto-striatal-cerebellar circuits, but also affect temporal, parietal and cingulate regions.
The aim of the present dissertation is to refine and apply two complementary methods of structural neuroimaging, in order to identify the brain circuits altered in
ADHD and relate them to different clinical ADHD subtypes and to known ADHD neuropsychological deficits. For that purpose, two structural MRI studies will be presented and discussed (Carmona et al. 2005; Tremols et al. 2008). The differential contributions of these studies, which represent a novelty and an improvement of previous ADHD studies, are: a) the application for the first time of
voxel-based morphometry analysis to compare ADHD children with non family related control children; b) the design and application of a new, easy to apply, manual method of caudate nucleus segmentation.
The results confirm previous findings about smaller brain volume in ADHD children, and refine this reduction by attributing it to grey matter (GM) volume. We also confirm abnormalities in fronto-striatal-cerebellar circuits as well as in parietal, cingulate and temporal regions. Specifically, we observed reductions in inferior frontal cortex, dorsal striatum, inferior parietal cortex and posterior cingulate cortex; thus explaining inhibition problems, spatial working memory deficits and visuospatial attentional alterations. We also observed GM volume reductions in emotionally driven areas such as orbitofrontal cortex, ventral striatum and middle temporal structures; thus accounting for dysfunctional delayed reward and motivational deficits. Interestingly, GM volume reductions, related to emotional processes are more prominent in H-I subtype, more preserved in combined subtypes, and relatively undisrupted in inattentive subtypes, which is in agreement with previous ADHD theories (Castellanos and Tannock 2002). We have also found GM deficits in "sensori-motor" areas (specifically in perirolandic cortex and supplementary motor area), and in the cerebellum. On the one hand, deficits in sensori-motor areas probably reflect problems in fine motor coordination. However, the fact that these reductions are especially prominent in combined and inattentive subtypes brings up the possibility that they may be related to attentional dysfunctions.
I hypothesized that deficits in these regions may produce a deficit when integrating and updating information from the external world and, in turn, produce a bias toward internal world focusing, thus, resulting in inattention. On the other hand, cerebellar reductions (which are extensively reported in ADHD literature) seem to be related to all cognitive, affective and sensorimotor deficits. The implication of cerebellum in all these dysfunctions may arise from its role as a modulator of the flow of information between fronto-strital circuits. Finally, our findings are also the first to show caudate head and body differential abnormalities in ADHD, which explain previous heterogeneous results, providing a new and reliable method to study striatal structures.
As a conclusion, GM volume reductions in emotional and cognitive areas support the implication of both hot (emotional) and cool (cognitive) functions, which agrees with most neuropsychological accounts of ADHD. To our knowledge this is the first time that a neuroanatomical study provides support for the existence of both cognitive and emotional dysfunctions in ADHD children. If these findings are replicated, they will constitute critical evidence for Sonuga-Barke's theory (Sonuga- Barke 2002; Sonuga-Barke 2003) about the dual route model.
REFERENCIAS:
1. Tremols V, Bielsa A, Soliva JC, Raheb C, Carmona S, Tomas J, et al. (2008): Differential abnormalities of the head and body of the caudate nucleus in attention deficit-hyperactivity disorder. Psychiatry Res. 163:270-278.
2. Carmona S, Vilarroya O, Bielsa A, Tremols V, Soliva JC, Rovira M, et al. (2005): Global and regional gray matter reductions in ADHD: a voxel-based morphometric study. Neurosci Lett. 389:88-93.
3. Castellanos FX, Tannock R (2002): Neuroscience of attention-deficit/hyperactivity disorder: the search for endophenotypes. Nat Rev Neurosci. 3:617-628.
5. Sonuga-Barke EJ (2003): The dual pathway model of AD/HD: an elaboration of neuro-developmental characteristics. Neurosci Biobehav Rev. 27:593-604.
6. Sonuga-Barke EJ (2002): Psychological heterogeneity in AD/HD--a dual pathway model of behaviour and cognition. Behav Brain Res. 130:29-36.

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Rokunuzzaman, Md, K. Sekiyama e T. Fukuda. "Real time detection and evaluation of Region of Interest by mobile robot using vision". IEEE, 2009. http://hdl.handle.net/2237/14033.

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17

Xia, Yan [Verfasser], e Andreas [Akademischer Betreuer] Maier. "Region-of-Interest Imaging with C-arm Computed Tomography / Yan Xia. Gutachter: Andreas Maier". Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2016. http://d-nb.info/1095885588/34.

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18

Melinder, Johanna, e Katja Melnikova. "Housing prices, stock prices and interest rates: a cointegration analyses of the Stockholm region". Thesis, Uppsala universitet, Statistiska institutionen, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-295656.

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This study examines the dynamic interaction between housing prices, stock prices and the repo rate in the Stockholm region by using the Johansen tests for cointegration. Several studies have been done on this topic, but the results are mixed across the world, and not many have been done in Scandinavia. This study contributes to the literature by examining eleven years of monthly data for the housing prices in the Stockholm region. We find evidence of a long-run relationship between housing prices, stock prices and the interest rate. There is a negative relationship between housing prices and the interest rate as well as between stock prices and the interest rate, but a positive relationship between housing prices and stock prices. However, the results are somewhat sensitive to model specification and therefore further studies on the topic are encouraged.

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19

R, V. Krishnam Raju Kunadha Raju. "Perceptual Image Quality Prediction Using Region of Interest Based Reduced Reference Metrics Over Wireless Channel". Thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-13631.

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As there is a rapid growth in the field of wireless communications, the demand for various multimedia services is also increasing. The data that is being transmitted suffers from distortions through source encoding and transmission over errorprone channels. Due to these errors, the quality of the content is degraded. There is a need for service providers to provide certain Quality of Experience (QoE) to the end user. Several methods are being developed by network providers for better QoE.The human tendency mainly focuses on distortions in the Region of Interest(ROI) which are perceived to be more annoying compared to the Background(BG). With this as a base, the main aim of this thesis is to get an accurate prediction quality metric to measure the quality of the image over ROI and the BG independently. Reduced Reference Image Quality Assessment (RRIQA), a reduced reference image quality assessment metric, is chosen for this purpose. In this method, only partial information about the reference image is available to assess the quality. The quality metric is measured independently over ROI and BG. Finally the metric estimated over ROI and BG are pooled together to get aROI aware metric to predict the Mean Opinion Score (MOS) of the image.In this thesis, an ROI aware quality metric is used to measure the quality of distorted images that are generated using a wireless channel. The MOS of distorted images are obtained. Finally, the obtained MOS are validated with the MOS obtained from a database [1].It is observed that the proposed image quality assessment method provides better results compared to the traditional approach. It also gives a better performance over a wide variety of distortions. The obtained results show that the impairments in ROI are perceived to be more annoying when compared to the BG.

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20

Barrera, Cruz Marco Antonio. "Hybrid method algebraic/inverse radon transform for region of interest reconstruction of computed tomography images /". To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2009. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.

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21

Lee, Shuk-ping. "Social stability and public policy the role of special interest groups in Macao /". Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B3642433X.

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22

Wong, Chi-wah Alec, e 王梓樺. "Exploiting wireless link adaptation and region-of-interest processing to improve real-time scalable video transmission". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B29804152.

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23

Ramamoorthy, Dhyanesh. "Muscle Fatigue Detection using Infrared Thermography: Image Segmentation to Extract the Region of Interest from Thermograms". University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1543923019568392.

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24

Hinckley, David William. "Multi-Satellite Formation Trajectory Design with Topological Constraints over a Region of Interest using Differential Evolution". ScholarWorks @ UVM, 2015. http://scholarworks.uvm.edu/graddis/404.

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Satellite formation missions allow for scientific measurement opportunities that are only otherwise possible with the use of unrealistically large satellites. This work applies the Evolutionary Algorithm (EA), Differential Evolution (DE), to a 4-satellite mission design that borrows heavily from the mission specifications for Phase 1 of NASA's Magnetospheric Multi-Scale Mission (MMS). This mission specifies goals for formation "quality" and size over the arc when scientific measurements are to be taken known as the Region of Interest (ROI). To apply DE to this problem a novel definition of fitness is developed and tailored to trajectory problems of the parameter scales of this mission. This method uses numerical integration of evolved initial conditions for trajectory determination. This approach allows for the inclusion of gravitational perturbations without altering the method. Here, the J2 oblateness correction is considered but other inclusions such as solar radiation pressure and other gravitational bodies are readily possible by amending the governing equations of integration which are stored outside of the method and called only during evaluation. A set of three launch conditions is evaluated using this method. Due to computational limitation, the design is restricted to only single-impulse maneuvers at launch and the ROI is initially restricted but then expanded through a process known here as "staging". The ROIs of tests are expanded until they fail to meet performance criteria; no result was able to stage to the full MMS specified $\pm20^\circ$ ROI but this is a result of the single-impulse restriction. The number of orbits a launch condition is able to meet performance criteria is also investigated. Revolutions considered and the ROIs therein contained are staged to investigate if the method is able to handle this additional problem space. Evidence of suitable formation trajectories found by this method is here presented.

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25

Koivukangas, T. (Tapani). "Methods for determination of the accuracy of surgical guidance devices:a study in the region of neurosurgical interest". Doctoral thesis, Oulun yliopisto, 2012. http://urn.fi/urn:isbn:9789514299049.

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Abstract Minimally invasive surgery (MIS) techniques have seen rapid growth as methods for improved operational procedures. The main technology of MIS is based on image guided surgery (IGS) devices, namely surgical navigators, surgical robotics and image scanners. With their widespread use in various fields of surgery, methods and tools that may be used routinely in the hospital setting for “real world” assessment of the accuracy of these devices are lacking. In this thesis the concept of accuracy testing was developed to meet the needs of quality assurance of navigators and robots in a hospital environment. Thus, accuracy was defined as the difference between actual and measured distances from an origin, also including determination of directional accuracy within a specific volume. Two precision engineered accuracy assessment phantoms with assessment protocols were developed as advanced materials and methods for the community. The phantoms were designed to include a common region of surgical interest (ROSI) that was determined to roughly mimic the size of the human head. These tools and methods were utilized in accuracy assessment of two commercial navigators, both enabling the two most widely used tracking modalities, namely the optical tracking system (OTS) and the electromagnetic tracking system (EMTS). Also a study of the accuracy and repeatability of a prototype surgical interactive robot (SIRO) was done. Finally, the phantoms were utilized in spatial accuracy assessment of a commercial surgical 3D CT scanner, the O-Arm. The experimental results indicate that the proposed definitions, tools and methods fulfill the requirements of quality assurance of IGS devices in the hospital setting. The OTS and EMTS tracking modalities were nearly identical in overall accuracy but had unique error trends. Also, the accuracy of the prototype robot SIRO was in the range recommended in the IGS community. Finally, the image quality of the O-Arm could be analyzed using the developed phantoms. Based on the accuracy assessment results, suggestions were made when setting up each IGS device for surgical procedures and for new applications in minimally invasive surgery
Tiivistelmä Mini-invasiivisen eli täsmäkirurgian tekniikoita ja teknologioita on alettu hyödyntää viime aikoina yhä enemmän. Tavoitteena on ollut parantaa kirurgisten operaatioiden tarkkuutta ja turvallisuutta. Täsmäkirurgiassa käytetyt teknologiat pohjautuvat kuvaohjattuihin kirurgisiin paikannuslaitteisiin. Kuvaohjattuihin laitteisiin kuuluvat navigaattorit, kirurgiset robotit ja kuvantalaitteet. Näiden laitteistojen kehittyminen on mahdollistanut tekniikoiden hyödyntämisen monialaisessa kirurgiassa. Paikannuslaitteistojen ja robottien yleistyminen on kuitenkin nostanut sairaaloissa esiin yleisen ongelman paikannustarkkuuden määrittämisessä käytännön olosuhteissa. Tässä väitöskirjassa esitetään kirurgisten yksiköiden käyttöön menetelmä sekä kaksi uutta fantomia ja protokollaa käytössä olevien paikannuslaitteistojen tarkkuuden määrittämiseen. Fantomit suunniteltiin sisältämään ennalta määritetty kirurginen kohdealue, mikä rajattiin käsittämään ihmisen kallon tilavuus. Fantomeita ja protokollaa hyödynnettiin kahden kaupallisen paikannuslaitteen tarkkuuden määrityksessä. Navigaattorit käyttivät optiseen ja elektromagneettiseen paikannukseen perustuvaa tekniikkaa. Lisäksi työssä kehitetyillä menetelmillä tutkittiin prototyyppivaiheessa olevan kirurgisen robotin paikannus- ja toistotarkkuutta sekä tietokonetomografialaitteen O-kaaren kuvan tarkkuuden määritystä. Kokeellisten tulosten perusteella työssä kehitetyt fantomit ja protokollat ovat luotettavia ja tarkkoja menetelmiä kirurgisten paikannuslaitteistojen tarkkuuden määrittämiseen sairaalaoloissa. Kirurgisten navigaattoreiden tarkkuuden määritystulokset osoittivat optisen ja elektromagneettisen paikannustekniikan olevan lähes yhtä tarkkoja. Prototyyppirobotin tarkkuus oli tulosten perusteella kirjallisuudessa esitettyjen suosituksien mukainen. Lisäksi O-kaaren kuvanlaatua voitiin tutkia kehitetyillä fantomeilla. Tarkkuudenmääritystulosten perusteella työssä ehdotetaan menetelmiä laitteistojen optimaalisesta käytöstä leikkaussalissa sekä laajennetaan niiden käyttömahdollisuuksia. Tuloksia voidaan hyödyntää myös paikannuslaitteistojen kehittämistyössä

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26

Kramer, Megan E. "The Neural Basis of Episodic Memory in Children: An fMRI Region of Interest Analysis of Hippocampal Activation". Cincinnati, Ohio : University of Cincinnati, 2006. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1145296202.

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Thesis (M.A.)--University of Cincinnati, 2006.
Title from electronic thesis title page (viewed Aug. 31, 2007). Includes abstract. Keywords: Episodic memory; Child; Functional magnetic resonance imaging (fMRI). Includes bibliographical references.

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27

Patel, Bhavin. "Creating a virtual slide map from sputum smear images for region-of-interest localisation in automated microscopy". Master's thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/3191.

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Includes abstract.
Includes bibliographical references (leaves 140-144).
Automated microscopy for the detection of tuberculosis (TB) in sputum smears seeks to address the strain on technicians in busy TB laboratories and to achieve faster diagnosis in countries with a heavy TB burden. As a step in the development of an automated microscope, the project described here was concerned with microscope auto-positioning; this primarily involves generating a point of reference on a slide, which can be used to automatically bring desired fields on the slide to the field-of-view of the microscope for re-examination. The study was carried out using a conventional microscope and Ziehl- Neelsen (ZN) stained sputum smear slides. All images were captured at 40x magnification. A digital replication, the virtual slide map, of an actual slide was constructed by combining the manually acquired images of the different fields of the slide. The geometric hashing scheme was found to be suitable for auto-stitching a large number of images (over 300 images) to form a virtual slide map. An object recognition algorithm, which was also based on the geometric hashing technique, was used to localise a query image (the current field-of-view) on the virtual slide map. This localised field-of-view then served as the point of reference. The true positive (correct localisation of a query image on the virtual slide map) rate achieved by the algorithm was above 88% even for noisy query images captured at slide orientations up to 26°. The image registration error, computed as the average mean square error, was less than 14 pixel2 (corresponding to 1.02 μm2 and 0.001% error in an image measuring 1030 x 1300 pixels) corresponding to a root mean square registration error of 3.7 pixels. Superior image registration accuracy was obtained at the expense of time using the scale invariant feature transform (SIFT), with a image registration error of 1 pixel2 (0.07 μm2). The object recognition algorithm is inherently robust to changes in slide orientation and placement, which are likely to occur in practice as it is impossible to place the slide in exactly the same position on the microscope at different times. Moreover, the algorithm showed high tolerance to illumination changes and robustness to noise.

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Moscoso, Rubino Eduardo. "Extremely Low and Variable Bandwidth Image Compression with Region of Interest Applied to Real Time Underwater Robotic Interventions". Doctoral thesis, Universitat Jaume I, 2018. http://hdl.handle.net/10803/482217.

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A new fast and progressive set-partitioning image compression parallel algorithm with Region Of Interest (ROI) which outputs an embedded bit oriented rate-distortion optimized stream and addresses very low bit rate compression is presented.User defined variable packet sizes make it suitable for the implementation of any communications protocols, either underwater or in any other scenario, while remaining competitive with current state-of-the-art compressors at higher bit rates.A parallel algorithm for the Discrete Wavelet Transform (DWT) based on the lifting scheme is also presented and it is shown to be optimal in the sense that no other implementation may be faster if memory saturation is achieved.The best ordering for the significant and refinement bits of the transform coefficients is derived, using the Mean Squared Error (MSE) as the error measure, by fitting a Probability Density Function (PDF) to the transform coefficients and weighting the error for each range of coefficients by its respective DWT subband gain.A general scheme for Region Of Interest (ROI), including a non-linear scaling ROI, is presented in which the lower bitplanes of the foreground coefficients are delayed in exchange for better background reconstruction, achieving a more effective blending of foreground and background information.Finally, an implementation for both 32-bit and 64-bit ARM and x86 architectures was validated in an actual wireless underwater robotic teleoperation context.
Se presenta un nuevo algoritmo rápido y progresivo de compresión de imagen con Region De Interés (ROI) que emite un flujo optimizado de distorsión y trata una compresión de tasa de bits muy baja. Los tamaños de paquete variables definidos por el usuario lo hacen adecuado para el implementación de cualquier protocolo de comunicación, ya sea bajo el agua o en cualquier otro escenario, sin dejar de ser competitivo con los actuales compresores de última generación a mayores tasas de bits. Un algoritmo paralelo para la Transformada Wavelet Discreta (DWT) basado en el esquema de lifting es también presentado y se muestra como óptimo en el sentido de que ninguna otra implementación puede ser más rápida si se logra la saturación de la memoria. Se obtiene el mejor orden para los bits significativos y de refinamiento de los coeficientes de transformación, usando el Error Cuadrático Medio (MSE), al ajustar una función de densidad de probabilidad (PDF) a los coeficientes de transformación y ponderar el error para cada rango de coeficientes por su respectiva ganancia de subbanda DWT. Se presenta un esquema general para la Región de Interés (ROI), incluyendo un ROI de escalado no lineal, en el cual los planos de bit más bajos de los coeficientes de primer plano se retrasan a cambio de una mejor reconstrucción de fondo, logrando una efectiva combinación de información de fondo y de frente. Finalmente, se validó una implementación para las arquitecturas ARM y x86 de 32 bits y de 64 bits en un contexto de teleoperación robótica bajo el agua real.

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Topping, Geoffrey John. "Positron emission tomography region of interest and parametric image analysis methods for severely-lesioned small animal disease models". Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2654.

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Small animal positron emission tomography (PET) image analysis can be particularly challenging with heavily-lesioned animal disease models with limited tracer uptake such as the 6-hydroxydopamine (OHDA) lesioned rat model of Parkinson's disease. Methodology-related variations in measured values of 10% or 15% can obscure meaningful biological differences, so accurate analysis methods are essential. However, placing regions of interest (ROIs) on these images without additional guidance is unreliable, and can lead to significant errors in results. To address this problem, this work develops a partly atlas-guided method place ROIs on structures that lack specific binding with presynaptic dopaminergic tracers. The method is tested by correlation of PET binding potential (BP) with autoradiographic binding measurements, and with repeated PET scans of the same subjects, both with the presynaptic tracer ¹¹C-dihydrotetrabenazine (DTBZ). The method is found to produce reliable results. When directly comparing PET images of the same subject to detect changes, it is essential to minimize variations due to analysis method. To this end, a masking method for automated image registration (AIR) of PET images with dopaminergic tracer rat images is developed. Coregistration with AIR and separate ROI placement are compared and tested with repeated scans of the same rat with DTBZ, and are found to be equivalent. Kinetic modelling algorithms may also introduce bias or scatter to binding potentials (BP) calculated from TACs or in parametric images. To determine the optimal method for this step, algorithms for dopaminergic tracers are compared for small animal DTBZ, ¹¹C-methylphenidate (MP), and ¹¹C-raclopride (Rac) data. Among the tested methods is a new variant of the Logan graphical kinetic modelling method, developed in this work, that issignificantly less biased by target tissue TAC noise than the standard Logan approach. The modified graphical method is further compared with the Logan graphical algorithms with added-noise simulations. The simplified reference tissue model (SRTM) is found to have the best method for ROI TAC data, while the modified graphical algorithm may be preferred when generating parametric images.

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McKnight, Calvin (Calvin Bruce) Carleton University Dissertation Geography. "Public art and urban spaces; the place of art in the public interest in the National Capital Region". Ottawa, 1996.

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Santiago, López Facundo A. "The europeanization of regional interest groups Catalonia, Tuscany and Wales in a comparative perspective". Doctoral thesis, Universitat Autònoma de Barcelona, 2014. http://hdl.handle.net/10803/285197.

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El principal objetivo de esta tesis es analizar el proceso de Europeización de los grupos de interés regionales (GIRs), explorando de qué manera, en qué medida y debido a que razones los GIRs han transformado sus valores, su organización y sus estrategias, adaptándolas a la lógica y formas de la Unión Europea (UE). Un GIR europeizado tiene valores y objetivos que son promovidos por la UE y los comparte con organizaciones similares alrededor del continente. Tiene una organización que le da preeminencia a los asuntos relativos a la UE, y es capaz de buscar, recibir y administrar fondos de la UE con eficacia. Finalmente, posee estrategias que superan las fronteras nacionales y regionales, lo que no solo significa trabajar en organizaciones pan-Europeas sino también acercarse a instituciones y actores mas allá de las arenas regionales y nacionales para intentar influenciar el desarrollo de las políticas de la UE. El estudio de la Europeización de los GIRs presenta un interés teórico y empírico para la ciencia política, dado que se encuentra en la intersección entre los estudios sobre Europeización, grupos de interés y regiones, donde la investigación es aún incipiente (Roller & Sloat, 2002; Constantelos, 2004; McCauley, 2010). Al parecer la Europeización de los GIRs varía dependiendo de la región que se observe, lo que lleva a nuestro interés en explicar de qué manera ocurren estas variaciones, y cuál puede ser su motive. Con este objetivo, planeamos primero medir el grado de Europeización, de los GIRs, lo que nos permitirá comparar e identificar variaciones entre ellos. En segundo lugar intentaremos explicar esas variaciones, haciendo uso de la variable de autoridad regional creada por Marks et al (2008), y teniendo en cuenta los factores intervinientes (Risse et al, 2001; Borzel & Risse, 2003) que pudiesen mediar en esta Europeización. Para analizar la Europeización de los GIRs, esta tesis propone un estudio comparativo de los GIRs en tres regiones diferentes de Europa. Cataluña, Toscana y Gales fueron elegidas por sus similitudes (Keating, 2009; Keating & Wilson, 2009; 2010) y su diferencia en la variable independiente de la autoridad regional (Hooghe et al, 2008). Para evitar la interferencia de las características de la política analizada, esta investigación se enfoca solo en la política ambiental, en la cual la UE tiene una capacidad regulativa considerable, y que es implementada no solo a nivel nacional sino principalmente a nivel regional. España, Italia y el Reino Unido están involucrados en procesos de descentralización desde hace cuatro décadas, así como en recientes reformas estatutarias (Keating, 2009). Este estudio espera encontrar diferencias en la Europeización de los GIRs de estas tres regiones. En este sentido, Cataluña, Toscana y Gales presentan una oportunidad invaluable para la comparación.
The main objective of this thesis is to analyse the process of Europeanization of regional interest groups (RIGs), exploring in which way, to which measure and due to which reasons RIGs have transformed their values, organization and strategies, adapting them to the logic and ways of the European Union (EU). A europeanized RIG has values and objectives that are championed by the EU and shares them with similar organizations around the continent. It has an organization that gives EU issues a prominent position, and is capable of searching for, receiving and administering EU funds with efficiency. Finally, it has strategies broader than the regional and national frontiers, which not only means working on pan-European organization, but also approaching actors and institutions beyond the regional and national arenas to try and influence EU policy-making. The study of the Europeanization of RIGs presents an empirical and theoretical interest for political science, as it stands in the intersection of the studies of Europeanization, interest groups and regions, where research is still incipient (Roller & Sloat, 2002; Constantelos, 2004; McCauley, 2010). It would appear that the Europeanization of RIGs varies depending on the region we observe, which leads to our interest in explaining in which way these variations occur, and which could be its driving force. For this purpose, we first plan to measure the degree of Europeanization of RIGs, which will allow us to compare and identify variations amongst them. Secondly, we will try to explain those variations, making use of the variable of regional authority created by Marks et al (2008), and taking account of the mediating factors (Risse et al, 2001; Borzel & Risse, 2003) that could intervene in this Europeanization. To analyse the Europeanization of RIGs, this thesis proposes a comparative study of the RIGs in three different regions of Europe. Catalonia, Tuscany and Wales were chosen for their similarities in many of their characteristics (Keating, 2009; Keating & Wilson, 2009; 2010) but their difference in relation to the independent variable of regional authority (Hooghe et al, 2008). In order to avoid an interference of the features of the policy analysed, this research was designed to focus on only one policy. We have selected the environmental policy, in which the EU has a considerable regulative capacity, and which is implemented not only on the national level but mainly on the regional level. Spain, Italy and the United Kingdom have been involved for the last four decades in processes of devolution and decentralization, as well as recent statute reforms (Keating, 2009).The study expects to find differences in the Europeanization of RIGs from these three regions. The fact that they are similar in most other aspects helps minimize the possibility of other explanations. In this sense, Catalonia, Tuscany and Wales present an invaluable possibility for comparison.

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32

Laipple, Daniel [Verfasser], e Andreas [Akademischer Betreuer] Schreyer. "Region of interest synchrotron nanotomography and nanodiffraction with FIB/SEM characterisation on engineering materials / Daniel Laipple. Betreuer: Andreas Schreyer". Hamburg : Staats- und Universitätsbibliothek Hamburg, 2015. http://d-nb.info/1073970396/34.

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Laipple, Daniel Verfasser], e Andreas [Akademischer Betreuer] [Schreyer. "Region of interest synchrotron nanotomography and nanodiffraction with FIB/SEM characterisation on engineering materials / Daniel Laipple. Betreuer: Andreas Schreyer". Hamburg : Staats- und Universitätsbibliothek Hamburg, 2015. http://nbn-resolving.de/urn:nbn:de:gbv:18-74020.

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34

Kjüllerstrüm, Mónica Isabel Bento De Braga. "Reservation income and the decision to borrow : an empirical analysis of interlinked informal credit contracts in the Peruvian Amazon". Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=29446.

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Abstract (sommario):

This thesis examines factors that determine household reliance on interlinked informal credit contracts for fish in the Peruvian Amazon, and the degree to which implicit interest rates in these contracts are explained by transaction costs, administrative costs and lender risk.
A probit model was used to determine household likelihood to borrow, using survey data collected in the region. This likelihood is found to depend on access to alternative activities to generate income, household resilience to income volatility, and demographics: age, education and mobility.
High implicit interest rates (112%) are not explained by the average costs (67%) incurred by local lenders. Market access and household demand elasticity seem to be the main factors determining the degree to which forest peasants are exploited. Local lenders are found to receive credit at rates below the cost to non-resident lenders who use the credit relationship to secure a supply of fish.

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35

Scalera, Jonathan E. "Image Chipping with a Common Architecture for Microsensors (CAuS)". Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/34172.

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Recent interest has emerged in microsensor platforms that are capable of supporting reconnaissance, surveillance and target acquisition operations. These devices typically consist of one or more sensors, signal conditioning and processing subsystems, a radio link and a power source. Sensors employed can range from acoustic, to seismic, to magnetic, to visible/infrared imagers.

A notable shortcoming of these systems is the fact that they are battery powered. The use of a finite power source places an upper limit on the lifespan of such a system. Thus, a major thrust in the development and usage of these microsensor platforms lies in the conservation of their limited energy resources. In attempt to reduce power consumption and hence extend the system's lifespan, communication bandwidths are often limited. In order to reduce the required bandwidth, much of the signal processing necessary to achieve a desired functionality must be performed within the microsensor platform itself.

This thesis effort provides this crucial bandwidth reduction by implementing in hardware an algorithm developed by the University of Maryland, which limits transmissions to the best view Regions-of-Interest (ROI) data, on the CAuS platform by BAE Systems. The hardware implementation was verified with a Matlab script that compared its results with those of the original algorithm. It was shown that these implementations were consistent for all of the data sets tested. Moreover, a subjective analysis, in which the detected ROIs were visually inspected, was performed to corroborate the former quantitative results.
Master of Science

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36

Rai, Debbie S. "A longitudinal study of closed head injury : neuropsychological outcome and structural analysis using region of interest measurements and voxel-based morphometry". Thesis, University of Stirling, 2005. http://hdl.handle.net/1893/92.

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Background: The hippocampus and corpus callosum have been shown to be vulnerable in head injury. Various neuroimaging modalities and quantitative measurement techniques have been employed to investigate pathological changes in these structures. Cognitive and behavioural deficiencies have also been well documented in head injury. Aims: The aim of this research project was to investigate structural changes in the hippocampus and corpus callosum. Two different quantitative methods were used to measure physical changes and neuropsychological assessment was performed to determine cognitive and behavioural deficit. It was also intended to investigate the relationship between structural change and neuropsychology at 1 and 6 months post injury. Method: Forty-seven patients with head injury (ranging from mild to severe) had undergone a battery of neuropsychological tests and an MRI scan at 1 and 6 months post injury. T1-weighted MRI scans were obtained and analysis of hippocampus and corpus callosum was performed using region-of-interest techniques and voxel-based morphometry which also included comparison to 18 healthy volunteers. The patients completed neuropsychological assessment at 1 and 6 months post injury and data obtained was analysed with respect to each assessment and with structural data to determine cognitive decline and correlation with neuroanatomy. Results: Voxel-based morphometry illustrated reduced whole scan signal differences between patients and controls and changes in patients between 1 and 6 months post injury. Reduced grey matter concentration was also found using voxel-based morphometry and segmented images between patients and controls. A number of neuropsychological aspects were related to injury severity and correlations with neuroanatomy were present. Voxel-based morphometry provided a greater number of associations than region-of-interest analysis. No longitudinal changes were found in the hippocampus or corpus callosum using region-of-interest methodology or voxel-based morphometry. Conclusions: Decreased grey matter concentration identified with voxel-based morphometry illustrated that structural deficit was present in the head injured patients and does not change between 1 and 6 months. Voxel-based morphometry appears more sensitive for detecting structural changes after head injury than region- of-interest methods. Although the majority of patients had suffered mild head injury, cognitive and neurobehavioural deficits were evidenced by a substantial number of patients reporting increased anxiety and depression levels. Also, the findings of relationships between reduced grey matter concentration and cognitive test scores are indicative of the effects of diffuse brain damage in the patient group.

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37

Schwan, Marco-Maximilian. "Quantitative assessment of nuclear bone scans using the “region of interest” technique as applied to the navicular bone and insertion of the deep digital flexor tendon regions in the distal phalanx of the horse". Doctoral thesis, Universitätsbibliothek Leipzig, 2005. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-33773.

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Die Grundlage für die Beurteilung von Szintigrammen im Bereich der Gliedmaße stellt der visuelle Vergleich mit der kontralateralen Seite dar. Eine Objektivierung anhand quantitativer Methoden ist daher, insbesondere bei Pferden mit bilateraler Lahmheit, von Bedeutung. Als Maß für den Anreicherungsgrad des Radiopharmakons in einem Areal werden sogenannte Speicherquotienten errechnet. In der Literatur finden sich für Speicherungen im Bereich des Strahlbeins nur wenig vergleichbare Werte, da die Auswahl der für die Bildung von Speicherquotienten nötigen Referenzareale nicht einheitlich erfolgt. Über die Auswertung im Bereich der Insertion der tiefen Beugesehne am Hufbein existieren kaum Angaben. Das Ziel der vorliegenden Arbeit ist es, Speicherquotienten für Anreicherungen im Bereich des Strahlbeins und der Insertion der tiefen Beugesehne am Hufbein zu ermitteln. Von Interesse ist vor allem die Beurteilung der Diskriminanz zwischen Patienten- und Kontrollgruppe in Abhängigkeit unterschiedlich gewählter Referenzareale. Weiterhin stellt sich die Frage, inwieweit Assoziationen zwischen Speicherquotienten und Lahmheitsgrad bzw. röntgenologischen Veränderungen bestehen
The use of bone scan images of the distal equine limb allows for the comparison of differences of radiopharmaceutical uptake between the contralateral limbs for diagnostic purposes. This type of quantitation is particularly valuable in horses which demonstrate bilateral lameness. In order to quantitate and compare the density of radiopharmaceutical in each of the limbs, one can compare the uptake from the so-called region of interest to that of a region of reference in the same leg. This method overcomes problems incurred in using values obtained from the literature because it is difficult to compare ratios of uptake when the choice of the reference areas are not the same. In addition, comparable values which are available are not well standardized. Specifically, the area of insertion of the deep digital flexor tendon (DDFT) to the coffin bone is hardly ever discussed. The primary objective of this study was to assess the ratios for increased uptake in the navicular bone and the area of insertion of the deep digital flexor tendon to the coffin bone. Of particular interest was the ability to discriminate between the diseased group and the control group which depended significantly on the reference points used. An additional question was whether or not any associations existed between ratios of uptake, degree of lameness or presence of radiolographic changes

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38

Rönnqvist, David, e Marie Mattiasson. "The small house market in the Stockholm region : A study of the impact of macroeconomic factors". Thesis, Jönköping University, JIBS, Economics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-8162.

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Buying a house is for most people the biggest investment they will ever make. A lot of factors are taken in to consideration when looking for the perfect house; location, size, what state it is in and so forth. But since most people’s budgets are limited, the price is probably the most important aspect in the decision making process of buying a house. It is therefore highly interesting to note that since 1981, house prices in Sweden have increased with almost 400 percent.

This thesis examines the relationship between small house prices and macroeconomic factors in the Stockholm region during the period 1991 to 2007. By using macro economic theories complemented by data for all Stockholm’s municipalities in a OLS regression, the thesis will explain how the variables affects the small house prices in a boom, recession and over time.

The results and analysis reveals that as house prices rises, people tend to increase their spending on interest costs and vice versa if the prices falls. Furthermore, results show that in a boom, an existence of speculation is contributing to the rise while convergence is an important factor in a recession. The most important conclusion from this thesis is the fact that the influence of macroeconomic variables on house prices differs significantly, depending on if the economy is in a recession or a boom. Finally, the influence on the economy that the house- and real estate market possesses cannot be underestimated with its important effect on the credit market, inflation and asset market.

Husköp är för de flesta människor deras livs största investering och det är därför många faktorer som först måste vägas in varav den viktigaste förmodligen är priset. Huspriserna i Sverige har sedan 1981 nästan fyrdubblats, en utveckling som är mycket kraftigare än inflationen samma tid.

Den här kandidatuppsatsen avser att undersöka Stockholmregionens småhuspriser åren 1981-2007 och dess relation till makroekonomiska faktorer. Genom att använda en OLS regression med insamlad data för Stockholms alla kommuner och makroekonomiska teorier, visar vi hur utvalda makroekonomiska variabler påverkar småhuspriserna generellt, i hög- samt lågkonjunktur.

Resultat och analys visar att om småhuspriserna går upp är tenderar Stockholms befolkning att lägga en större del av deras inkomst på räntekostnader och tvärtom när priserna går ner. En psykologisk aspekt har en viktig del i dessa upp och nedgångar, i en uppgång startar en spekulationsperiod då människor vill vara en del ägandet i den uppåtgående husmarknad medans i en nergång skapas en sorts konvergens och en rad faktorer påverkar varandra i en spiralliknande nedåt trend. Denna trend kan förklaras i DiPasquales och Wheatons assets market model där det positiva förhållandet mellan marknader som hyresmarknaden, kreditmarknaden, byggmarknaden och tillgångsmarknaden står i fokus. Den viktigaste slutsatsen i uppsatsen är att makroekonomiska faktorer påverkar småhuspriserna helt olika beroende på om ekonomin är i en hög eller lågkonjunktur. Slutligen bör nämnas hur viktigt hus- och fastighetsmarknaden är för en ekonomi genom dess påverkan på kreditmarknaden och inflationen.

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39

Nebelung, Heiner [Verfasser], Ivan [Akademischer Betreuer] Platzek e Klaus [Gutachter] Zöphel. "CT-Koronarangiographie: Einfluss der Positionierung der Region of Interest beim Bolus-Tracking auf die Bildqualität / Heiner Nebelung ; Gutachter: Klaus Zöphel ; Betreuer: Ivan Platzek". Dresden : Technische Universität Dresden, 2019. http://d-nb.info/1227196598/34.

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40

Grilliat, Sophie. "L'action collective métropolitaine des entreprises ordonnatrices de la globalisation : analyse comparée des stratégies d'influence à Londres et en Ile-de-France". Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1193.

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L'action collective métropolitaine des entreprises ordonnatrices de la globalisation. Analyse comparée des stratégies d'influence à Londres et en Ile-de-France
The metropolitan collective action of globalizing companies: a comparative analysis of strategies of influence in the London and Paris regions

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41

Cangoz, Coskun Mehmet. "Redistribution Of Power And Status Through Public Finance: The Case Of Turkey (1980-2003)". Phd thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/2/12611085/index.pdf.

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This dissertation explores whether fiscal policies can be used as a means of redistribution of power and status, and the ways of transferring state&rsquo
s economic power to social groups. In this regard, state budget is recognized as the main tool for the execution of redistributive policies of the governments. In this framework, this study investigates how budget was employed to change power balance of social groups during the period of 1980-2003, in Turkey. In order to measure the changing power balances budget expenditures and revenues are reclassified and the size of the financial resources allocated or transferred to the particular social groups are determined. The analysis of budget data demonstrated that budget in Turkey has a strong influence on redistributive politics. Regarding the policy making point of view, the traditional centralist approach was deteriorated and increasing number of parties and interest groups involved in budget mechanisms. Another finding is supporting the particular economic or social groups within the current time period or across the periods either through the withdrawal of state sector from the area of traditionally publicly provided private goods
transferring budget resources and changing the taxation policies or by borrowing.

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42

Huck, Sascha Manuel [Verfasser], e Katia [Akademischer Betreuer] Parodi. "Development and validation of two novel x-ray filters in computed tomography with focus on fluence modulation for region-of-interest imaging / Sascha Manuel Huck ; Betreuer: Katia Parodi". München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2021. http://d-nb.info/1241963754/34.

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43

GOGINENI, SRI LOHITH. "DEVELOPMENT OF AN ROI AWARE FULL-REFERENCE OBJECTIVE PERCEPTUAL QUALITY METRIC ON IMAGES OVER FADING CHANNEL". Thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-13610.

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In spite of technological advances in wireless systems, transmitted data suffers from impairments through both lossy source coding and transmission overerror prone channels. Due to these errors, the quality of multimedia content is degraded. The major challenge for service providers in this scenario is to measure the perceptual impact of distortions to provide certain Quality of Experience(QoE) to the end user. The general tendency of the Human Visual System (HVS) suggests that the artifacts in the Region-of-Interest (ROI) are perceived to be more annoying compared to the artifacts in Background (BG). With this assumption, the thesis aims to measure the quality of image over ROI and BG independently. Visual Information Fidelity (VIF), a full-reference image quality assessment is chosen for this purpose. Finally, the metric measured over ROI and BG are pooled to get a ROI aware metric. The ROI aware metric is used to predict the Mean Opinion Score (MOS) of an image. In this study, an ROI aware quality metric is used to measure the quality of a set of distorted images generated using a wireless channel. Eventually, MOS of the distorted images is estimated. Lastly, the predicted MOS is validated with the MOS obtained from subjective tests. Testing the proposed image quality assessment approach shows an improved prediction performance of ROI aware quality metric over traditional image quality metrics. It is also observed that the above approach provides a consistent improvement over a wide variety of distortions. After extensive research, the obtained results suggest that the impairments in the ROI are perceived to be more annoying than that of the BG.

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44

Nilsson, Martin. "Body Ownership : An Activation Likelihood Estimation Meta-Analysis". Thesis, Högskolan i Skövde, Institutionen för biovetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-18853.

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How is it that we feel that we own our body? And how does the brain create this feeling? By manipulating the integration of multisensory signals, researchers have recently begun to probe this question. By creating the illusory experience of owning external body-parts and entire bodies, researchers have investigated the neurofunctional correlates of body ownership. Recent attempts to quantitatively synthesize the neuroimaging literature of body ownership have shown inconsistent results. A large proportion of functional magnetic resonance imaging (fMRI) findings on body ownership includes region of interest (ROI) analysis. This analysis approach produces inflated findings when results are synthesized in meta-analyses. We conducted a systematic search of the fMRI literature of ownership of body-parts and entire bodies. Two activation likelihood estimation (ALE) meta-analyses were conducted, testing the impact of including ROI-based findings. When ROI-based results were included, frontal and posterior parietal multisensory areas were associated with body ownership. However, a whole-brain meta-analysis, excluding ROI-based results, found no significant convergence of activation across the brain. These findings highlight the difficulty of quantitatively synthesizing a neuroimaging field where a large part of the literature is based on findings from ROI analysis. We discuss the difficulty of quantitatively synthesizing results based on ROI analysis and suggest future directions for the study of body ownership within the field of cognitive neuroscience.

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45

Chan, Annika. "Metodoptimering för hjärtamyloidos". Thesis, Malmö universitet, Fakulteten för hälsa och samhälle (HS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-26621.

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Amyloidos uppstår när amyloid, felveckade proteiner, ackumuleras extracellulärt i vävnaden. Det finns två typer av amyloid som ger upphov till hjärtamyloidos: lätt immunoglobulinkedja amyloidos (AL-amyloidos) och transtyretinamyloidos (TTR-amyloidos). TTR-amyloidos delas in i hereditär transtyretinamyloidos (hATTR) och wild-type transtyretinamyloidos (wtATTR). Beroende på vilken typ av amyloidos ges olika behandlingar. Idag används alltmer en icke-invasiv nuklearmedicinsk undersökning, för diagnostik och differentiering vid hjärtamyloidos. Bedömningen är visuell och utgår från ett utarbetat graderingssystem av Perugini. Vid klinisk fysiologi och nuklearmedicin på Skånes universitetssjukhus har efterfrågan av den nuklearmedicinska undersökningen för hjärtamyloidos ökat. Syftet med denna studie är att optimera hjärtscintigrafi amyloidos med 99mTc-DPD genom beräkning av antalet counts i SPECT/CT och i planara bilder, och därefter beräkna aktiviteten per kilogram kroppsvikt för att undersöka om stråldosen till patienten kan minskas. Dessutom kommer en jämförelse mellan manuella och cirkulära ROI att utföras för att undersöka om någon skillnad föreligger. Denna retrospektiva studie omfattade tidigare genomförda undersökningar och hitintills har 17 patienter genomgått hjärtamyloidos scintigrafi med 99mTc-DPD. Resultaten av studien visade ingen signifikant skillnad mellan cirkulära och manuella ROI (p = 0,504), vilket talade för en god överensstämmelse. För att reducera stråldosen till patienten kan viktbaserad dosmängd vara ett alternativ i framtiden.
Amyloidosis occurs when amyloid, misfolded proteins, accumulate extracellularly in the tissue. There are two types of amyloid that cause cardiac amyloidosis: immunoglobulin light chain amyloidosis (AL amyloidosis) and transthyretin amyloidosis (TTR amyloidosis). TTR amyloidosis is divided into hereditary transthyretin amyloidosis (hATTR) and wild-type transthyretin amyloidosis (wtATTR). Different treatments are available depending on what type of amyloidosis. Today, a non-invasive nuclear medicine examination is increasingly being used for the diagnosis and differentiation of cardiac amyloidosis. The assessment of cardiac amyloidosis involves a visual assessment based on the Perugini grading system. In the Clinical Physiology and Nuclear medicine Department at Skåne University Hospital, there is an increasing demand for cardiac amyloidosis scintigraphy with 99mTc-DPD. The aim of this study is to optimize 99mTc-DPD scintigraphy for cardiac amyloidosis by identifying the number of counts in planar and in SPECT/CT images. The patient’s body weight will also be studied to determine if the patient’s radiation dose can be reduced. In addition, a comparison between manual and circular region of interest (ROI) will be performed to examine whether a difference exists. The study involved a retrospective analysis of 17 patients that have undergone cardiac amyloidosis scintigraphy with 99mTc-DPD. The results showed no significant difference between circular and manual ROI (p = 0.504), which indicated good agreement. Weight-based radiation dose may be an alternative in the future, in order to reduce the radiation dose to the patient.

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46

O'Leary, Brian. "A Vertex-Based Approach to the Statistical and Machine Learning Analyses of Brain Structure". University of Toledo / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1576254162111087.

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47

Cheng, Guangchun. "Video Analytics with Spatio-Temporal Characteristics of Activities". Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc799541/.

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As video capturing devices become more ubiquitous from surveillance cameras to smart phones, the demand of automated video analysis is increasing as never before. One obstacle in this process is to efficiently locate where a human operator’s attention should be, and another is to determine the specific types of activities or actions without ambiguity. It is the special interest of this dissertation to locate spatial and temporal regions of interest in videos and to develop a better action representation for video-based activity analysis. This dissertation follows the scheme of “locating then recognizing” activities of interest in videos, i.e., locations of potentially interesting activities are estimated before performing in-depth analysis. Theoretical properties of regions of interest in videos are first exploited, based on which a unifying framework is proposed to locate both spatial and temporal regions of interest with the same settings of parameters. The approach estimates the distribution of motion based on 3D structure tensors, and locates regions of interest according to persistent occurrences of low probability. Two contributions are further made to better represent the actions. The first is to construct a unifying model of spatio-temporal relationships between reusable mid-level actions which bridge low-level pixels and high-level activities. Dense trajectories are clustered to construct mid-level actionlets, and the temporal relationships between actionlets are modeled as Action Graphs based on Allen interval predicates. The second is an effort for a novel and efficient representation of action graphs based on a sparse coding framework. Action graphs are first represented using Laplacian matrices and then decomposed as a linear combination of primitive dictionary items following sparse coding scheme. The optimization is eventually formulated and solved as a determinant maximization problem, and 1-nearest neighbor is used for action classification. The experiments have shown better results than existing approaches for regions-of-interest detection and action recognition.

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48

Subramanian, Vivek. "Content-aware Video Compression". Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254394.

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In a video there are certain regions in the image that viewers focus on more than others, which are called the salient regions or RegionsOf-Interest (ROI). This thesis aims to improve the perceived quality of videos by improving the quality of these ROis while degrading the quality of the other non-ROI regions of a frame to keep the same bitrate as would have been the case otherwise. This improvement is achieved by using saliency maps generated using an eye tracker or a deep neural network and providing this information to a modified video encoder. In this thesis the open source x264 encoder was chosen to make use of this information. The effects of ROI encoding are studied for high quality 720p videos by encoding them at low bitrates. The results indicate that ROI encoding can improve subjective video quality when carefully applied.
I en video £inns <let vissa delar av bilden som tittarna fokuserar mer pa an andra, och dessa kallas Region of Interest". Malet med den har uppsatsen ar att hoja den av tittaren upplevda videokvaliteten genom att minska kompressionsgraden ( och darmed hoja kvaliteten) i de iogonfallande delarna av bilden, samtid som man hojer kompressionsgraden i ovriga delar sa att bitraten blir den samma som innan andringen. Den har forbattringen gors genom att anvanda Saliency Mapsssom visar de iogonfallande delarna for varje bildruta. Dessa Saliency Maps"har antingen detekterats med hjalp av en Eye Tracker eller sa har de raknats fram av ett Neuralt Natverk. Informationen anvands sedan i en modifierad version av den oppna codecen x264 enligt en egendesignad algoritm. Effekten av forandringen har studerats genom att koda hogkvalitativa kallfiler vid lag bitrate. Resultaten indikerar att denna metod kan forbattra den upplevda kvaliteten av en video om den appliceras med ratt styrka.

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49

Aziz, Hussein. "Streaming Video over Unreliable and Bandwidth Limited Networks". Doctoral thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-00560.

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The main objective of this thesis is to provide a smooth video playout on the mobile device over wireless networks. The parameters that specify the wireless channel include: bandwidth variation, frame losses, and outage time. These parameters may affect the quality of the video negatively, and the mobile users may notice sudden stops during the playout video, i.e., the picture is momentarily frozen, followed by a jump from one scene to a different one. This thesis focuses on eliminating frozen pictures and reducing the amount of video data that need to be transmitted. In order to eliminate frozen scenes on the mobile screen, we propose three different techniques. In the first technique, the video frames are split into sub-frames; these sub-frames are streamed over different channels. In the second technique the sub-frames will be “crossed” and sent together with other sub-frames that are from different positions in the streaming video sequence. If some sub-frames are lost during the transmission a reconstruction mechanism will be applied on the mobile device to recreate the missing sub-frames. In the third technique, we propose a Time Interleaving Robust Streaming (TIRS) technique to stream the video frames in different order. The benefit of that is to avoid losing a sequence of neighbouring frames. A missing frame from the streaming video will be reconstructed based on the surrounding frames on the mobile device. In order to reduce the amount of video data that are streamed over limited bandwidth channels, we propose two different techniques. These two techniques are based on identifying and extracting a high motion region of the video frames. We call this the Region Of Interest (ROI); the other parts of the video frames are called the non-Region Of Interest (non-ROI). The ROI is transmitted with high quality, whereas the non-ROI is interpolated from a number of references frames. In the first technique the ROI is a fixed size region; we considered four different types of ROI and three different scenarios. The scenarios are based on the position of the reference frames in the streaming frame sequence. In the second technique the ROI is identified based on the motion in the video frames, therefore the size, position, and shape of the ROI will be different from one video to another according to the video characteristic. The videos are coded using ffmpeg to study the effect of the proposed techniques on the encoding size. Subjective and objective metrics are used to measure the quality level of the reconstructed videos that are obtained from the proposed techniques. Mean Opinion Score (MOS) measurements are used as a subjective metric based on human opinions, while for objective metric the Structural Similarity (SSIM) index is used to compare the similarity between the original frames and the reconstructed frames.

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Viana, Juheina Lacerda Ribeiro. "Espacialização da infraestrutura urbana em ambientes metropolitanos – o caso de Trindade, entre 2010 e 2015". Universidade Federal de Goiás, 2016. http://repositorio.bc.ufg.br/tede/handle/tede/6904.

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Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
A questão metropolitana no Brasil ganhou destaque nos estudos de geografia urbana nas últimas décadas. Temáticas como mobilidade intrametropolitana, habitação e saneamento básico são alguns temas constantemente debatidos. É muito comum iniciar esse tipo de análise pela centralização e polarização de equipamentos e recursos do núcleo metropolitano em detrimento às dinâmicas socioespaciais que ocorrem nos municípios periféricos. A Região Metropolitana de Goiânia não foge à característica centralizadora e polarizadora dos núcleos metropolitanos brasileiros. Esse perfil de organização socioespacial reverbera em outras tendências, como valorização do solo urbano de suas áreas centrais, insuficiência de estoques de áreas rurais para fins de parcelamento, ou de construção de habitações populares. Essa dinâmica não reflete impactos apenas em Goiânia, uma vez que, inicialmente, os municípios limítrofes recebem a função de saldar as demandas habitacionais do núcleo metropolitano, potencializando assim, o surgimento de novas demandas relacionadas à infraestrutura e serviços. No município de Trindade esse processo ganhou evidência a partir da década de 1970, com o início da conurbação da área leste municipal (Trindade II), com a área oeste de Goiânia, exemplo da implantação dos setores Maysa, Setor dos Bandeirantes e de muitos outros setores na década de 1990, a exemplo do Jardim Ipanena, Setor Renata Park e Conjunto Dona Iris I. A GO 060 contribui para o crescimento dessa área conurbada, uma vez que potencializava os deslocamentos cotidianos. No decorrer da pesquisa se observou uma dinâmica muito comum nesses setores: a negligência do poder público municipal diante das demandas da população. Alguns impasses identificados a partir de dados do censo do IBGE de 2010 na área conurbada são, na sua maioria, vinculados à falta de infraestrutura urbana, a exemplo de pavimentação asfáltica, escoamento pluvial, rede de água, dentre outros. Comparando com o núcleo original do município, percebe-se que o Trindade II é omitido pela gestão municipal. Essa afirmativa se confirma a partir da espacialização dos equipamentos de consumo coletivo e dos serviços. Enfim, nota-se claramente um processo de fragmentação sociopolítica do território, impulsionada, sobretudo, pela desintegração das funções públicas de interesse comum mencionadas na legislação metropolitana da RMG. Esse processo gera ainda na malha urbana conurbada à Goiânia (Trindade II) o que denominamos de “tecido urbano duplamente periférico”, uma vez que é negligenciado tanto pela gestão municipal de Trindade quanto de Goiânia, muito embora salde suas demandas por habitação.
A questão metropolitana no Brasil ganhou destaque nos estudos de geografia urbana nas últimas décadas. Temáticas como mobilidade intrametropolitana, habitação e saneamento básico são alguns temas constantemente debatidos. É muito comum iniciar esse tipo de análise pela centralização e polarização de equipamentos e recursos do núcleo metropolitano em detrimento às dinâmicas socioespaciais que ocorrem nos municípios periféricos. A Região Metropolitana de Goiânia não foge à característica centralizadora e polarizadora dos núcleos metropolitanos brasileiros. Esse perfil de organização socioespacial reverbera em outras tendências, como valorização do solo urbano de suas áreas centrais, insuficiência de estoques de áreas rurais para fins de parcelamento, ou de construção de habitações populares. Essa dinâmica não reflete impactos apenas em Goiânia, uma vez que, inicialmente, os municípios limítrofes recebem a função de saldar as demandas habitacionais do núcleo metropolitano, potencializando assim, o surgimento de novas demandas relacionadas à infraestrutura e serviços. No município de Trindade esse processo ganhou evidência a partir da década de 1970, com o início da conurbação da área leste municipal (Trindade II), com a área oeste de Goiânia, exemplo da implantação dos setores Maysa, Setor dos Bandeirantes e de muitos outros setores na década de 1990, a exemplo do Jardim Ipanena, Setor Renata Park e Conjunto Dona Iris I. A GO 060 contribui para o crescimento dessa área conurbada, uma vez que potencializava os deslocamentos cotidianos. No decorrer da pesquisa se observou uma dinâmica muito comum nesses setores: a negligência do poder público municipal diante das demandas da população. Alguns impasses identificados a partir de dados do censo do IBGE de 2010 na área conurbada são, na sua maioria, vinculados à falta de infraestrutura urbana, a exemplo de pavimentação asfáltica, escoamento pluvial, rede de água, dentre outros. Comparando com o núcleo original do município, percebe-se que o Trindade II é omitido pela gestão municipal. Essa afirmativa se confirma a partir da espacialização dos equipamentos de consumo coletivo e dos serviços. Enfim, nota-se claramente um processo de fragmentação sociopolítica do território, impulsionada, sobretudo, pela desintegração das funções públicas de interesse comum mencionadas na legislação metropolitana da RMG. Esse processo gera ainda na malha urbana conurbada à Goiânia (Trindade II) o que denominamos de “tecido urbano duplamente periférico”, uma vez que é negligenciado tanto pela gestão municipal de Trindade quanto de Goiânia, muito embora salde suas demandas por habitação.

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