<p>Studies of modern communication media such as Cell Phones and so called Instant Messengers are popular today. This study focused on these modern techniques, focused on parents as a target group and on what is important for them in everyday communication.</p><p>By exploratory using three focus groups it became clear that the children, and the link to them was the absolute most important thing for the parents. It became clear that this link to a great extent today exists through the mobile phone.</p><p>In a following study a Mobile Instant Messenger called My Friends was introduced. It was used by two families during two weeks to see how it would change the communication within the family. The focus was to see how problems with availability were handled, it turned out that:</p><p>My friends had a more obvious way of indicating availability than the Cell Phone had. It was also consulted before making contact through other media.</p><p>Emphasis was also put to find out what kind of communication the different media; phone call (Cell Phone), texting and Instant Messenger supports. It showed that three variables seemed to be important when choosing media:</p><p>• the haste of the business</p><p>• the goal of the business</p><p>• the need for precision</p><p>The bigger knowledge two people had of each other the more the latter was affected but the first two were unaffected.</p> / <p>Studier av moderna kommunikationsmedia som mobiltelefonen och så kallade Instant Messengers är populära idag. Denna studie fokuserade på dessa moderna tekniker, och koncentrerade sig på målgruppen föräldrar, och vad som är viktigt för dem i deras vardagskommunikation.</p><p>Genom att först i explorativt syfte använda tre fokusgrupper framkom det att barnen, och länken till dem, var det absolut viktigaste för föräldrarna. Det framgår i studien att länken till barnen idag till stor del finns genom mobiltelefonen.</p><p>I en andra studie introducerades en mobil Instant Messenger kallad My Friends. Denna användes av två familjer under två veckors tid för att se hur den rådande kommunikationen inom familjen förändrades.</p><p>Här fokuserades det på hur problem med tillgänglighet löstes, och det visade sig att:</p><p>My Friends hade ett tydligare sätt att visa tillgänglighet än mobiltelefonen, och den konsulterades ibland även när den faktiska kommunikationen skedde genom andra media.</p><p>Stor emfas lades också på att utröna vilken typ av kommunikation de olika medierna mobiltelefoni, SMS och Instant Messenger stödjer. Det visade sig att tre variabler verkar vara viktiga när val av kommunikationsmedia görs:</p><p>• ärendets brådska</p><p>• ärendets mål</p><p>• behov av exakthet</p><p>Ju större kännedom två personer hade om varandra desto mer påverkades den senare medan de två föregående förblev oförändrade.</p>

The main objective of this research was to exploit the interrelations between the rheological behavior and nano-microstructure of complex fluids in solving two state-of-the-art problems, one in the field of biomedical engineering: controlling the amount and characteristics of bioaerosol droplets generated during coughing, and the other in the bitumen-heavy oil industry: characterizing the nano-microstructure of asphaltene particles in bitumen and heavy oil from their rheological behavior. For the first problem, effect of viscoelastic and surface properties of artificial mucus simulant gels on the size distribution and amount of airborne bioaerosol droplets generated during simulated coughing were investigated. The results revealed that suppressing the generation of bioaerosol droplets and/or reducing the number of emitted droplets to a minimum during coughing are practically achievable through modulation of mucus viscoelastic properties. While variation of surface tension did not show any change in the droplet size distribution, an increase in particle size was observed as the samples changed from elastic solid type to viscoelastic type to viscous fluid type samples. This knowledge will help in the development of a new class of drugs being developed at the University of Alberta, aimed at controlling the transmission of airborne epidemic diseases by modifying the viscoelastic properties of mucus. For the second problem, studies of viscoelastic behavior of Athabasca bitumen (Alberta) and Maya crude (Mexico) oil samples, along with their Nano-filtered and chemically separated-plus-reconstituted samples were performed. The results revealed that the rheological behaviors of the bitumen-heavy oil samples are governed by their multiphase nature. The rheological behavior of all feeds, permeates and retentate samples followed a single master curve over the entire temperature interval, consistent with that of a slurry comprising a Newtonian liquid plus a dispersed solid comprising non-interacting hard spheres. The behavior of asphaltenes in the reconstituted samples, however, was found to be significantly different from that in nanofiltered samples. The information about the characteristics and behaviors of asphaltenes obtained in this study will help better understand the asphaltene structures, and support the effort to determine solutions for numerous asphaltene-related industrial problems. In the long run, this knowledge will help to create more efficient extraction and upgrading processes for bitumen and heavy oils. / Thermo Fluids

No description available.

Magnetic Resonance Imaging (MRI) is an important diagnostic tool for imaging soft tissue without the use of ionizing radiation. Moreover, through advanced signal processing, MRI can provide more than just anatomical information, such as estimates of tissue-specific physical properties. Signal processing lies at the very core of the MRI process, which involves input design, information encoding, image reconstruction, and advanced filtering. Based on signal modeling and estimation, it is possible to further improve the images, reduce artifacts, mitigate noise, and obtain quantitative tissue information. In quantitative MRI, different physical quantities are estimated from a set of collected images. The optimization problems solved are typically nonlinear, and require intelligent and application-specific algorithms to avoid suboptimal local minima. This thesis presents several methods for efficiently solving different parameter estimation problems in MRI, such as multi-component T2 relaxometry, temporal phase correction of complex-valued data, and minimizing banding artifacts due to field inhomogeneity. The performance of the proposed algorithms is evaluated using both simulation and in-vivo data. The results show improvements over previous approaches, while maintaining a relatively low computational complexity. Using new and improved estimation methods enables better tissue characterization and diagnosis. Furthermore, a sequence design problem is treated, where the radio-frequency excitation is optimized to minimize image artifacts when using amplifiers of limited quality. In turn, obtaining higher fidelity images enables improved diagnosis, and can increase the estimation accuracy in quantitative MRI.

Gamma oscillations of local field potentials (LFP) in the basal ganglia and thalamus had not been studied during saccades. Eleven patients were studied during deep brain stimulation (DBS); 6 were in the subthalamic nucleus (STN); 3 in the globus pallidus interna (GPi); and 2 in the thalamic ventralis intermedius nucleus (Vim). Patients performed horizontal saccades to visual targets while LFPs from DBS electrodes, scalp electroencephalogram (EEG), and electrooculogram (EOG) were recorded. Wavelet spectrograms were generated and saccade onset and event-related gamma synchronizations (ERS) were compared to baseline without eye motion. ERS were recorded at and after saccade onset in the STN, GPi and Vim, EEGs and EOGs; but were absent during target light illumination without saccades. ERS were symmetric in all DBS contacts and appeared identical in DBS LFPs, frontal EEGs and EOGs. These findings indicate their origin from extraocular muscle spike potentials rather than brain neural activity.

Gamma oscillations of local field potentials (LFP) in the basal ganglia and thalamus had not been studied during saccades. Eleven patients were studied during deep brain stimulation (DBS); 6 were in the subthalamic nucleus (STN); 3 in the globus pallidus interna (GPi); and 2 in the thalamic ventralis intermedius nucleus (Vim). Patients performed horizontal saccades to visual targets while LFPs from DBS electrodes, scalp electroencephalogram (EEG), and electrooculogram (EOG) were recorded. Wavelet spectrograms were generated and saccade onset and event-related gamma synchronizations (ERS) were compared to baseline without eye motion. ERS were recorded at and after saccade onset in the STN, GPi and Vim, EEGs and EOGs; but were absent during target light illumination without saccades. ERS were symmetric in all DBS contacts and appeared identical in DBS LFPs, frontal EEGs and EOGs. These findings indicate their origin from extraocular muscle spike potentials rather than brain neural activity.

With the advance of the LCD technology, video quality is becoming increasingly important. In this thesis, we develop hardware-friendly low-complexity enhancement algorithms. Video quality enhancement methods can be classified into two main categories. Single frame methods are the first category. These methods have generally low computational complexity. Multi-frame methods combine information from more than one frame and require the motion information of objects in the scene to do so. We first concentrate on the contrast-enhancement problem by using both global (frame-wise) and local information derived from the image. We use the image histogram and present a regularization-based histogram modification method to avoid problems that are often created by histogram equalization. Next, we design a compression artifact reduction algorithm that reduces ringing artifacts, which is disturbing especially on large displays. Furthermore, to remove the blurriness in the original video we present a non-iterative diffusion-based sharpening algorithm, which enhances edges in a ringing-aware fashion. The diffusion-based technique works on gradient approximations in a neighborhood individually. This gives more freedom compared to modulating the high-pass filter output that is used to sharpen the edges. Motion estimation enables applications such as motion-compensated noise reduction, frame-rate conversion, de-interlacing, compression, and super-resolution. Motion estimation is an ill-posed problem and therefore requires the use of prior knowledge on motion of objects. Objects have inertia and are usually larger then pixels or a block of pixels in size, which creates spatio-temporal correlation. We design a method that uses temporal redundancy to improve motion-vector search by choosing bias vectors from the previous frame and adaptively penalizes deviations from the bias vectors. This increases the robustness of the motion-vector search. The spatial correlation is more reliable because temporal correlation is difficult to use when the objects move fast or accelerate in time, or have small sizes. Spatial smoothness is not valid across motion boundaries. We investigate using energy minimization for motion estimation and incorporate the spatial smoothness prior into the energy. By formulating the energy minimization iterations for each motion vector as the primal problem, we show that the dual problem is motion segmentation for that specific motion vector.

This Master of Arts by research was comprised of two components: creative practice (60%) and a written thesis (40%). The creative practice was partially represented in an exhibition of paintings, drawings, photographs and artist books entitled Traces, held at WiseART Gallery, 166 Ann St, Brisbane, March 2005. The written component is represented in this manuscript. This case study illustrates the creative process of an individual artistic practice through intuitive inquiry, which utilized self-observation methods such as painting, drawing, photographing, bookmaking, exhibitions, journaling, questioning and mindfulness. Intuitive inquiry is outlined as the predominant method of both the phenomenon of art making in this case, as well as the method used to study the creative process. The concept of intuitive inquiry as a research method, by its similarity to this particular creative process, was well suited to studying its delicate, preconscious, internally reflective and reflexive activities. Intuitive inquiry also underpins the exceptional, transformative experiences of the artist, which are often excluded from conventional empirical research. The results of this study demonstrate that it is through the hermeneutic interpretations of process, product and dialogue that a deeper understanding of the creative process is gained. The hermeneutic model of creative process that emerged (Fig 4.14) will assist others in a deeper understanding of how creative process can be utilized in generating new knowledge. More importantly, it is this creative interpretive process that can lead to transformative experiences, which encourage both the artist and the audience to search for a deeper engagement with each other and the world.

Electrocardiography (ECG) has been established as one of the most useful diagnostic tools in medicine and is critical in the management of various heart conditions. Automated or semi-automated ECG analysis algorithms are expected to play an important role in the utilization of the ECG data. The correct identification of the QRS complexes is a fundamental step in every ECG analysis method. A major problem that is often encountered in automatic QRS detection is the presence of artifacts in the ECG data, which cause considerable alterations to the signal. Some common filters can smooth the effect of the artifacts, however they cannot eliminate them due to their spectral frequency overlap with the signal components. In this thesis, the objective was to develop a method, based on Time-Frequency Analysis that would be able to automatically detect and remove artifacts in order to increase the reliability of automatic QRS detection. The ECG data used for this purpose was taken from the Physionet library and more specifically from the MIMIC II database. The data in this database was acquired from ICU patients and it contains various types of rhythms as well as artifacts. First, a Graphical User Interface (GUI) was developed in order to manually annotate ECG data and was used for creating the ground truth for testing the methods developed. The Time-Frequency Analysis method used for the analysis of the ECG data, was based on a time-varying Autoregressive (AR) model whose solutions were obtained using Burg’s method. Several factors that affect the effectiveness of the method were investigated in order to optimize the algorithm experimentally. The algorithm implemented performs three main functions: “Artifact Hypothesis Testing,” “Artifact Detection and Removal,” and “QRS Complex Detection.” The first step, “Artifact Hypothesis Testing,” examines whether the signal contains any artifact or not. This is performed with a correct classification rate of 95.56%. The second step was the “Artifact Detection and Removal,” which could detect and remove the artifact area with an accuracy of 95.60% based on each signal sample identified as artifact or not. The final step, the “QRS Complex Detection,” correctly identified 92% of QRS complexes (322 out of 335 annotated QRS complexes). Finally, the proposed method was compared with one of the most commonly used methods in ECG analysis, the Wavelet Transform Analysis (WTA). The two methods were tested on exactly the same dataset. The WTA resulted in an overall score of 65.3% mainly due to the large number of false positive detections in the regions of artifact. / Το ηλεκτροκαρδιογράφημα (ΗΚΓ) έχει καθιερωθεί ως ένα από τα πιο χρήσιμα εργαλεία διάγνωσης στην ιατρική και είναι πολύ σημαντικό στη διαχείριση καρδιαγγειακών παθήσεων. Αυτοματοποιημένοι ή ημι-αυτοματοποιημένοι αλγόριθμοι ανάλυσης του ΗΚΓ αναμένεται να έχουν σημαντικό ρόλο στη χρήση των δεδομένων του ΗΚΓ. Η σωστή αναγνώριση των συμπλεγμάτων QRS είναι βασικό βήμα σε κάθε μέθοδο ανάλυσης του ΗΚΓ. Ένα σημαντικό πρόβλημα που συχνά προκύπτει σε αυτόματη ανίχνευση QRS είναι η παρουσία των τεχνητών σφαλμάτων (artifacts) στα δεδομένα ΗΚΓ, τα οποία προκαλούν σημαντικές αλλαγές στο σήμα. Κάποια κοινά φίλτρα μπορούν να εξομαλύνουν τις επιπτώσεις των τεχνητών σφαλμάτων, ωστόσο δεν μπορούν να τα εξαλείψουν λόγω της μεγάλης επικάλυψης του φάσματος συχνοτήτων τους με αυτού των στοιχείων του σήματος. Στην παρούσα εργασία στόχος ήταν η ανάπτυξη μιας μεθόδου, βασισμένης στην Ανάλυση Χρόνου-Συχνότητας, που θα είναι σε θέση να εντοπίσει αυτόματα και να αφαιρεί τα τεχνητά σφάλματα, ώστε να έχουμε μια πιο αξιόπιστη μέθοδο αυτόματης ανίχνευσης των QRS. Τα δεδομένα ΗΚΓ που χρησιμοποιήθηκαν για το σκοπό αυτό λήφθηκαν από τη βιβλιοθήκη Physionet και πιο συγκεκριμένα από τη βάση δεδομένων MIMIC II. Τα δεδομένα σε αυτή τη βάση δεδομένων προέρχονται από ασθενείς της Μονάδας Εντατικής Θεραπείας, και ως εκ τούτου, περιέχουν διάφορα είδη ρυθμών αλλά και τεχνητών σφαλμάτων. Αρχικά, ένα Γραφικό Περιβάλλον Χρήστη (GUI), σχεδιάστηκε για τη χειροκίνητη σηματοδότηση των διάφορων περιοχών ΗΚΓ σημάτων και χρησιμοποιήθηκε για τη δημιουργία των αληθών αποτελεσμάτων για δοκιμή της μεθόδου. H Ανάλυση Χρόνου-Συχνότητας έγινε με τη χρήση ενός χρονικά μεταβαλλόμενου Αυτοπαλινδρομικού (AR) μοντέλου οι λύσεις του οποίου βρέθηκαν με τη μέθοδο Burg. Ακολούθησε η διερεύνηση διαφόρων παραγόντων που επηρεάζουν την αποτελεσματικότητα της μεθόδου, προκειμένου να βελτιστοποιηθεί πειραματικά η μέθοδος. Ο αλγόριθμος που υλοποιήθηκε εκτελεί τρεις βασικές λειτουργίες: “Artifact Hypothesis Testing,” “Artifact Detection and Removal” και “QRS Complex Detection.” Κατ’ αρχήν, το βήμα "Artifact Hypothesis Testing" εξετάζει αν το σήμα περιέχει τεχνητό σφάλμα ή όχι, με το ποσοστό σωστής ταξινόμησης να ανέρχεται στο 95.56%. Το δεύτερο βήμα, η ανίχνευση και αφαίρεση της περιοχής του τεχνητού σφάλματος, έγινε με ακρίβεια 95.60% με βάση το πόσα σημεία του σήματος αναγνωρίστηκαν ως τεχνητό σφάλμα ή όχι. Τέλος, το συνολικό ποσοστό ορθής ανίχνευσης των συμπλεγμάτων QRS ήταν 92% (322 από τα 335 QRS που επισημάνθηκαν χειροκίνητα). Τέλος, έγινε μια σύγκριση μεταξύ της προτεινόμενης μεθόδου και μιας μεθόδου ανάλυσης ΗΚΓ που χρησιμοποιείται πολύ συχνά, της ανάλυσης με Μετασχηματισμό Wavelet (WTA). Οι δύο μέθοδοι δοκιμάστηκαν στα ίδια ακριβώς δεδομένα. Η ορθή ανίχνευση των συμπλεγμάτων QRS με τη μέθοδο WTA ήταν 65.3% κυρίως λόγω του μεγάλου αριθμού ψευδώς θετικών αποτελεσμάτων στις περιοχές των τεχνητών σφαλμάτων.

Actuellement, le développement du travail en mode projet, ainsi que le travail en réseaux, entraînent de profondes modifications dans la manière de concevoir les espaces de travail et les bureaux. Les entreprises qui conçoivent ces espaces associent souvent des architectes et des designers.La thèse a pour objet de répondre à la question suivante : comment les connaissances nouvelles sont elles générées dans les activités de conception relatives au domaine de l'aménagement des espaces de travail ?Le premier chapitre s'articulera autour des différents travaux relatifs aux activités deconception (travaux de Lebahar, Hatchuel et Visser, etc.). Le second s'intéressera aux différentes théories relatives à la génération des connaissances (travaux de Nonaka, Tsoukas et Engeström, etc).Afin de répondre à notre question de recherche, nous avons mis en place un dispositif d'observation de longue durée au sein des entreprises étudiées (approche de nature ethnométhdologique). Il s'agit de deux entreprises parisiennes spécialisées dans l'aménagement des espaces de travail: Génie des Lieux et Workspace CBRE.Nous avons montré que des difficultés d'intercompréhension apparaissent dans les activités de conception. Ces obstacles sont dûs à l'existence des connaissances tacites relationnelles au sens d'Harry Collins. Ces dernières peuvent être rendues explicites par la conception d'objets intermédiaires. Nous avons vu également comment la conception des artefacts en deux dimensions et en trois dimensions permet la génération des connaissances nouvelles et utiles dans un projet d'aménagement d'espaces de travail. / The development of this work is currently carried out in a project mode, since working in the network requires deep modifications in a way of conceiving the workspaces as well as the offices. The enterprises that conceive these spaces often associate both the designers and the architects.The purpose of this present thesis is to answer the flowing question: how are the recent knowledges generated in the conception activities which appear in the field of work space planning?The first chapter focuses on the works related to the conception activities (works of Lebahar, Hatchuel and Visser...etc...). The second deals with the different theories relating to the generation of knowledge (works of Nonaka, Tsoukas and Engeström... etc...).To answer our research question, we have installed a device which requires a long_term intervention inside the enterprises meant for study (ethnomethodological approach). There are two Parisian enterprises that specialize in work space planning: (GENIE DES LIEUX and workspace CBRE).During the work, we have shown some difficulty intercomprehension that emerged in the conception activities. We have concluded, as a result, that these obstacles were due to relational tacit knowledges (RTK) according to Harry Collins theory. However these difficulties can be made explicit by the conception of intermediate objects.We have also noticed that ho when conceiving the artifacts into two and three dimensions, this allows the generation of new and useful knowledges in a project of work space planning.