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Art of Documentation: The Sherborne Missal and the Role of Documents in English Medieval ArtBerenbeim, Jessica January 2012 (has links)
This dissertation considers an unfamiliar but fundamental aspect of late-medieval art: the role of documentation. Documents played as critical a part in that society as they do in our own. In late-medieval consciousness, the charter loomed as large as the sacred image, and documentation mattered no less than devotion—while the two also had a profound and inextricable connection. Discussion begins with three principal arguments, explained in detail in the first chapter: 1. The materials of documentation are part of the history of art; and accordingly, art-historical methods render an important contribution to diplomatics. 2. Documents are an important subject of representation; and accordingly, works of art are important sources for the cultural reception of documentary practices. 3. Documents are an important model for representation; and, consequently, an understanding of the paradigmatic role of the document suggests an alternative dimension to the interpretation of late-medieval art. The chapters that follow pursue these arguments through the analysis of individual works of art—charters, seals, archival manuscripts, liturgical manuscripts, architecture, and sculpture. These chapters also include a study of one of the great monuments of English gothic art: the Sherborne Missal, produced c.1400 for the Benedictine abbey of Sherborne. Ideas of documentation constitute critical aspects both of the Missal’s subject matter and its modes of representation, and these “documentary” elements also relate closely to the larger ideological project of the Missal’s creators. As details of the manuscript’s patronage, illumination, liturgy, inscriptions, and codicology all demonstrate, its creators associated documentation with central religious ideas about devotional images and the eucharist—essentially, the nature of valid representation and effective action. In keeping with the regional and institutional context of this principal study, the other objects discussed come primarily from English religious institutions. That context, however, by no means implies that the importance of documentation is limited either to England or to the conventual sphere, although it manifests itself differently from place to place and from one estate to another. The studies in this thesis represent only one example of where its arguments might lead, and what its approach might reveal in other works of art. / History of Art and Architecture
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Μελέτη αξιοποίησης της ηλιακής ενέργειας για τον έλεγχο του φωτισμού και της θερμοκρασίας του θερμοκήπιου / Study of development of solar radiation for irradiation and temperature control in greenhouseΚαυγά, Αγγελική 28 June 2007 (has links)
Στην διπλωματική αυτή εργασία παρουσιάζονται οι πτυχές σχετικά με τον έλεγχο του φωτισμού στα θερμοκήπια με τη χρήση των φακών Fresnel ως διαφανή καλύμματα καθώς και τα αποτελέσματα του συνδυασμού των γραμμικών φακών Fresnel με θερμικά (Τ), φωτοβολταικά (PV) ή υβριδικά φωτοβολταϊκά/θερμικά (PV/T) συστήματα μετατροπής της πλεονάζουσας ηλιακής ακτινοβολίας εντός του θερμοκηπίου σε ηλεκτρική ενέργεια και θερμότητα. Τα συστήματα αυτά μελετούνται σχετικά με την απόδοσή τους στην κάλυψη των θερμικών και ηλεκτρικών αναγκών μιας χαρακτηριστικής θερμοκηπιακής μονάδας, δίνοντας κατ / We present aspects and results concerning irradiation control in greenhouses by using glass type fresnel lenses as transparent covering material. We also present results of the combination of the fresnel lenses with thermal (T), photovoltaic (PV) or hybrid photovoltaic/thermal (PV/T) type absorbers to convert the surplus of the solar radiation inside the greenhouse into electricity and heat. The suggested systems are studying regarding their performance in covering thermal and electrical needs of a typical greenhouse unit, giving also the estimated benefits.
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Superresolution Nonlinear Structured Illumination Microscopy By Stimulated Emission DepletionZhang, Han January 2014 (has links)
The understanding of the biological processes at the cellular and subcellular level requires the ability to directly visualize them. Fluorescence microscopy played a key role in biomedical imaging because of its high sensitivity and specificity. However, traditional fluorescence microscopy has a limited resolution due to optical diffraction. In recent years, various approaches have been developed to overcome the diffraction limit. Among these techniques, nonlinear structured illumination microscopy (SIM) has been demonstrated a fast and full field superresolution imaging tool, such as Saturated-SIM and Photoswitching-SIM. In this dissertation, I report a new approach that applies nonlinear structured illumination by combining a uniform excitation field and a patterned stimulated emission depletion (STED) field. The nature of STED effect allows fast switching response, negligible stochastic noise during switching, low shot noise and theoretical unlimited resolution, which predicts STED-SIM to be a better nonlinear SIM. After the algorithm development and the feasibility study by simulation, the STED-SIM microscope was tested on fluorescent beads samples and achieved full field imaging over 1 x 10 micron square at the speed of 2s/frame with 4-fold improved resolution. Our STED-SIM technique has been applied on biological samples and superresolution images with tubulin of U2OS cells and granules of neuron cells have been obtained. In this dissertation, an effort to apply a field enhancement mechanism, surface plasmon resonance (SPR), to nonlinear STED-SIM has been made and around 8 time enhancement on STED quenching effect was achieved. Based on this enhancement on STED, 1D SPR enhanced STED-SIM was built and 50 nm resolution of fluorescence beads sample was achieved. Algorithm improvement is required to achieve full field superresolution imaging with SPR enhanced STED-SIM. The application of nonlinear structured illumination in two photon light-sheet microscopy is also studied in this dissertation. Fluorescent cellular imaging of deep internal organs is highly challenging because of the tissue scattering. By combining two photon Bessel beam light-sheet microscopy and nonlinear SIM, 3D live sample imaging at cellular resolution in depth beyond 200 microns has been achieved on live zebrafish. Two-color imaging of pronephric glomeruli and vasculature of zebrafish kidney, whose cellular structures located at the center of the fish body are revealed in high clarity.
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MATCHED WAVEFORM DESIGN AND ADAPTIVE BEAMSTEERING IN COGNITIVE RADAR APPLICATIONSRomero, Ric January 2010 (has links)
Cognitive Radar (CR) is a paradigm shift from a traditional radar system in that previous knowledge and current measurements obtained from the radar channel are used to form a probabilistic understanding of its environment. Moreover, CR incorporates this probabilistic knowledge into its task priorities to form illumination and probing strategies thereby rendering it a closed-loop system. Depending on the hardware's capabilities and limitations, there are various degrees of freedom that a CR may utilize. Here we will concentrate on two: temporal, where it is manifested in adaptive waveform design; and spatial, where adaptive beamsteering is used for search-and-track functions. This work is divided into three parts. First, comprehensive theory of SNR and mutual information (MI) matched waveform design in signal-dependent interference is presented. Second, these waveforms are used in a closed-loop radar platform performing target discrimination and target class identification, where the extended targets are either deterministic or stochastic. The CR's probabilistic understanding is updated via the Bayesian framework. Lastly, we propose a multiplatform CR network for integrated search-and-track application. The two radar platforms cooperate in developing a four-dimensional probabilistic understanding of the channel. The two radars also cooperate in forming dynamic spatial illumination strategy, where beamsteering is matched to the channel uncertainty to perform the search function. Once a target is detected and a track is initiated, track information is integrated into the beamsteering strategy as part of CR's task prioritization.
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Wave Model and Watercraft Model for Simulation of Sea StateKrus, Kristofer January 2014 (has links)
The problem of real-time simulation of ocean surface waves, ship movement and the coupling in between is tackled, and a number of different methods are covered and discussed. Among these methods, the finite volume method has been implemented in an attempt to solve the problem, along with the compressible Euler equations, an octree based staggered grid which allows for easy adaptive mesh refinement, the volume of fluid method and a variant of the Hyper-C advection scheme for compressible flows for advection of the phase fraction field. The process of implementing the methods that were chosen proved to be tricky in many ways, as they involve a large number of advanced topics, and the implementation that was implemented in this thesis work suffered from numerous issues. There were for example problems with keeping the interface intact, as well as a harsh restriction on the time step size due to the CFL condition. Improvements required to make the method sustainable for real-time applications are discussed, and a few suggestions on alternative approaches that are already in use for similar purposes are also given and discussed. Furthermore, a method for compensating for gain/loss of mass when solving the incompressible flow equations with an inaccurately solved pressure Poisson equation is presented and discussed. A momentum conservative method for transporting the velocity field on staggered grids without introducing unnecessary smearing is also presented and implemented. A simple, physically based illumination model for sea surfaces is derived, discussed and compared to the Blinn–Phong shading model, although it is never implemented. Finally, a two-dimensional partial differential equation in the spatial domain for simulating water surface waves for mildly varying bottom topography is derived and discussed, although it is deemed to be too slow for real-time purposes and is therefore never implemented. / <p>This publication differs from the printed version of the report in the sense that links are blue in this version and black in the printed version.</p>
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Automatinio valdymo apsvietimo sistemu efektyvumo tyrimas / Investigation of efficiency of automatic control lighting systemsPetronis, Julius 23 June 2006 (has links)
In this thesis are investigated lighting control systems, peculiarities of lighting systems, classification, requests, counting methods. There are given a lot of information about daylight and illumination, in analytical part. In reference with illumination values, given in the hygiene norms, there are calculated the number of illuminators in the room. Lighting control systems efficiency is investigated by comparison manual lighning control with automatic. In this thesis are investigated, how many power we lose, when selecting manual control system instead of automatic control system with digital devices. According to results of experiment, there are made characteristic of power deppencies on illumination. Conclusions are formulated at the end of a transaction.
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Curvelet-domain preconditioned "wave-equation" depth-migration with sparseness and illumination constraintsHerrmann, Felix J., Moghaddam, Peyman P. January 2004 (has links)
A non-linear edge-preserving solution to the least-squares migration problem with sparseness & illumination constraints is proposed. The applied formalism explores Curvelets as basis functions. By virtue of their sparseness and locality, Curvelets not only reduce the dimensionality of the imaging problem but they also naturally lead to a dense preconditioning that almost diagonalizes the normal/Hessian operator.
This almost diagonalization allows us to recast the imaging problem into a ’simple’ denoising problem. As such, we are in the position to use non-linear estimators based on thresholding. These estimators exploit
the sparseness and locality of Curvelets and allow us to compute a first estimate for the reflectivity, which approximates the least-squares solution of the seismic inverse scattering problem. Given this estimate,
we impose sparseness and additional amplitude corrections by solving a constrained optimization problem. This optimization problem is initialized and constrained by the thresholded image and is designed to remove remaining imaging artifacts and imperfections in the estimation and reconstruction.
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Portraits of patrons in Byzantine religious manuscripts.Franses, Henri January 1987 (has links)
Byzantine religious manuscripts were commissioned by people from many levels of society. Several contain portraits of their commissioners, represented together with a holy figure. An analysis of these scenes, examining features such as the holy figures represented and their specific iconographic meaning, and the relation of mortal to divine, reveals many facets of Byzantine art, religion and society. This analysis indicates a major distinction between portraits representing the emperor, and those depicting all other patrons. Non-imperial portraits show deep personal devotion and piety. The manuscripts in which they occur were commissioned to honour the holy figure, and many request salvation in return. Imperial commissions, on the other hand, were not votive gifts. Their portraits stress the public, political, and occasionally religious role of the emperor as the elected of God upon earth, and head of state. These portraits are thus highly informative of several aspects of Byzantine life.
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Novel Approaches in Structured Light IlluminationWang, Yongchang 01 January 2010 (has links)
Among the various approaches to 3-D imaging, structured light illumination (SLI) is widely spread. SLI employs a pair of digital projector and digital camera such that the correspondences can be found based upon the projecting and capturing of a group of designed light patterns. As an active sensing method, SLI is known for its robustness and high accuracy. In this dissertation, I study the phase shifting method (PSM), which is one of the most employed strategy in SLI. And, three novel approaches in PSM have been proposed in this dissertation. First, by regarding the design of patterns as placing points in an N-dimensional space, I take the phase measuring profilometry (PMP) as an example and propose the edge-pattern strategy which achieves maximum signal to noise ratio (SNR) for the projected patterns. Second, I develop a novel period information embedded pattern strategy for fast, reliable 3-D data acquisition and reconstruction. The proposed period coded phase shifting strategy removes the depth ambiguity associated with traditional phase shifting patterns without reducing phase accuracy or increasing the number of projected patterns. Thus, it can be employed for high accuracy realtime 3-D system. Then, I propose a hybrid approach for high quality 3-D reconstructions with only a small number of illumination patterns by maximizing the use of correspondence information from the phase, texture, and modulation data derived from multi-view, PMP-based, SLI images, without rigorously synchronizing the cameras and projectors and calibrating the device gammas. Experimental results demonstrate the advantages of the proposed novel strategies for 3-D SLI systems.
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Rotate and Hold and Scan (RAHAS): Structured Light Illumination for Use in Remote AreasCrane, Eli Ross 01 January 2011 (has links)
As a critical step after the discovery of material culture in the field, archaeologists have a need to document these findings with a slew of different physical measurements and photographs from varying perspectives. 3-D imaging is becoming increasingly popular as the primary documenting method to replace the plethora of tests and measurements, but for remote areas 3-D becomes more cumbersome due to physical and environmental constraints. The difficulty of using a 3-D imaging system in such environments is drastically lessened while using the RAHAS technique, since it acquires scans untethered to a computer. The goal of this thesis is to present the RAHAS Structured Light Illumination technique for 3-D image acquisition, and the performance of the RAHAS technique as a measurement tool for documentation of material culture on a field trip to the Rio Platano Biosphere in Honduras.
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