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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

LA REPRESENTACIÓN DEL ESPACIO EN LA OBRA FOTOGRÁFICA DE KOLDO CHAMORRO: LA PROXÉMICA COMO METODOLOGÍA

Rabasco Peiró, Mario 02 May 2016 (has links)
[EN] The representation of space in the photographic work of Koldo Chamorro: Proxemics as methodology This thesis investigates the work's methodology by photographer Koldo Chamorro throughout his photographic career related to the use of focal lengths used in the genre of photographic reportage, developed and perfected by him over time. This methodology of representation was implemented by him from the mid-70s until his death in 2009. This particular way of working made him part of the logic of proxemics, that is, the scientific study of the use of the man's personal space and social as cultural phenomenon. It is known as proxemics the part of semiotics that is dedicated to the study of communication through relations of proximity and distance between people and objects during the interaction, gestures adopted and the possible existence or absence of physical contact. The aim of this thesis is to analyze the system of work in terms of focal lengths and formats are concerned, applied to photographic genres used by the artist Koldo Chamorro in his work. By ordering his creative universe this thesis facilitates the future task of selecting his work, according to the author around four million negative. In this sense, this thesis, the hypotheses and conclusions of this research can serve as reference to curators, historians and future researchers in editing and curating his work and his figure in the history of Spanish Photography. Likewise and at the same level, the aim of this thesis is to analyze and verify the validity of this system as a whole or partially, for potential application in a educational level. In this sense, as photography lecturer within the world of photography there is no precedent on the subject discussed in this thesis. It has been found and proposed from research, a coherent, simple and effective method that allows students, future professionals or artists in the field, to have a consistent, synthetic, repeatable and open to a "real world of possibilities" method gravitating between the technical, theoretical and the plastic. To support the theses and hypotheses of this research and travel the paths that the author traveled to obtain the method, the research has been based in a considerable amount of photographs, unknown most of them to date, fact that has greatly facilitated the corroboration of the final hypothesis this thesis. / [ES] La representación del espacio en la obra de Koldo Chamorro: La proxémica como metodología. La presente tesis doctoral ha investigado la metodología de trabajo relacionada con el uso de las distancias focales utilizadas en el género del reportaje fotográfico, que ha sido desarrollada y perfeccionada en el tiempo por el fotógrafo Koldo Chamorro a lo largo de su carrera fotográfica. Dicha metodología de representación la puso en práctica desde mediados de los años 70 hasta su fallecimiento en el año 2009, hecho que lo inscribe en la lógica de la proxémica, entendida como la parte de la semiótica que se dedica al estudio de la comunicación a través de las relaciones de proximidad y de alejamiento entre las personas y objetos durante la interacción, los gestos adoptados y la posible existencia o ausencia de contacto físico. Se trata, por tanto, de un método que tiene muy presente la proxémica, es decir, el estudio científico del uso por parte del hombre del espacio personal y social como fenómeno cultural. El objetivo de esta tesis ha sido analizar el sistema de trabajo en cuanto a distancias focales y formatos se refiere, aplicado a los géneros fotográficos y utilizado por el artista Koldo Chamorro en su obra, ordenando su universo creativo; para, de este modo, facilitar en el futuro la tarea de selección de su obra estimada, según el autor, en cuatro millones de negativos. Se trata por tanto, de que la tesis, hipótesis y conclusiones de esta investigación puedan servir de referencia a comisarios, historiadores y futuros investigadores en la edición y recolocación de su obra y su figura en la historia de la fotografía española. De igual modo y al mismo nivel, el objetivo de esta tesis ha sido analizar y corroborar la validez del sistema total o parcialmente para su potencial aplicación a nivel docente, ya que como profesor en la materia dentro del mundo de la fotografía no existen precedentes sobre el tema tratado en esta tesis a nivel proyectual. Se ha encontrado y propuesto a partir de la investigación, un método coherente, sencillo y eficaz que permita a los estudiantes, futuros profesionales o artistas en la materia, disponer de un método consistente, sintético, repetible y abierto a un "verdadero mundo de posibilidades" proyectuales que gravitan entre lo técnico, lo teórico y lo plástico. Para poder sustentar las tesis e hipótesis de esta investigación y recorrer los caminos que el autor recorrió hasta la obtención del método, se ha dispuesto de abundante material, en su mayoría inédito, hecho que ha facilitado en gran medida la corroboración de las hipótesis finales de la presente tesis. / [CA] La representació de l'espai en l'obra de Koldo Chamorro: La proxèmica com a metodologia. La present tesi doctoral ha investigat la metodologia de treball relacionada amb l'ús de les distàncies focals utilitzades en el gènere del reportatge fotogràfic, desenvolupada i perfeccionada en el temps pel fotògraf Koldo Chamorro al llarg de la seua carrera fotogràfica. Aquesta metodologia de representació la posà en pràctica a partir de mitjans dels anys 70 fins a la seua mort en l'any 2009, fet que l'inscriu en la lògica de la proxèmica, és a dir, de l'estudi científic de l'ús per part de l'home de l'espai personal i social com a fenomen cultural. La proxèmica és coneguda com la part de la semiòtica que es dedica a l'estudi de la comunicació mitjançant les relacions de proximitat i d'allunyament entre les persones i els objectes durant la interacció, els gestos adoptats i la possible existència o absència de contacte físic. L'objectiu d'aquesta tesi ha estat analitzar el sistema de treball quant a distàncies focals i formats es refereix, aplicat als gèneres fotogràfics i utilitzat per l'artista Koldo Chamorro en la seua obra, ordenant el seu univers creatiu; per a, d'aquesta manera, facilitar en el futur la tasca de selecció de la seua obra estimada, segons l'autor, en quatre milions de negatius; a fi que la tesi, les hipòtesis i les conclusions d'aquesta investigació puguen servir de referència a comissaris, historiadors i futurs investigadors en l'edició i recol·locació tant de la seua obra com de la seua figura en la història de la fotografia espanyola. D'igual manera i al mateix nivell, l'objectiu d'aquesta tesi ha estat analitzar i corroborar la validesa del sistema totalment o parcialment per a la seua potencial aplicació a nivell docent ja que com a professor en la matèria, a nivell projectual, dintre del món de la fotografia no existeixen precedents al voltant del tema tractat en aquesta tesi. S'ha trobat i proposat a partir de la investigació, un mètode coherent, senzill i eficaç que permeta als estudiants, futurs professionals o artistes en la matèria, disposar d'un mètode consistent, sintètic, repetible i obert a un "vertader món de possibilitats" projectuals que graviten entre allò tècnic, allò teòric i allò plàstic. Per a poder sustentar les tesis i les hipòtesis d'aquesta investigació i recórrer els camins que l'autor recorregué fins a l'obtenció del mètode, s'ha disposat del suficient material en la majoria inèdit, fet que ha facilitat en gran mesura la corroboració de les hipòtesis finals de la present tesi. / Rabasco Peiró, M. (2016). LA REPRESENTACIÓN DEL ESPACIO EN LA OBRA FOTOGRÁFICA DE KOLDO CHAMORRO: LA PROXÉMICA COMO METODOLOGÍA [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/63227
52

Computer model of a focal plane array

Thvedt, Tom Arnold, 1956- January 1988 (has links)
The background and operation of charge transfer devices is reviewed, and a computer model simulation of focal plane arrays is presented. The model provides an option to predict the performance of a focal plane. With this program, any of the allowed materials, detectors, readout structures, or preamplifiers that make up a focal plane, may be selected to create new designs for analysis. Only surface channel devices are considered, and only references to the spectral dependence are presented. The computer model's operation and validity is supported by over 70 equations and more than 50 figures, including actual computer screen printouts. Standard equations followed by brief discussions are used to support the menu driven program. The structure and operation of the computer model is presented, but not the actual software source code.
53

EVALUATION OF A SCHOTTKY BARRIER INFRARED CHARGE-COUPLED DEVICE.

Hudson, Leland Ray. January 1982 (has links)
No description available.
54

Improved designs for future thermal imagers

Ibrahim, Hassan January 2000 (has links)
No description available.
55

Qualitative Assessment of Activated Microglia and Astrocytes in Focal Cortical Dysplasia: Case Series of Pediatric Patients

Yee, Nicole 22 May 2017 (has links)
A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine. / Epilepsy is the most common neurologic condition seen in children. Focal cortical dysplasia (FCD), a seizure disorder characterized by abnormal cortical laminar development, comprises approximately 75% of medically intractable epilepsies in the pediatric population. A greater appreciation of the pathology and intrinsic properties of the epileptogenic zone may help in understanding why FCD lesions are drug‐resistant, and could potentially lead to more effective treatments in the pediatric population. Neuronal support cells such as microglia and astrocytes have shown to have a role in FCD pathology. These cells are also activated during aging and traumatic brain injury as evidence by morphological change. This study aims to characterize the spatial distribution of microglia and astrocytes using immunohistochemistry in dysplastic tissue of eight male pediatric patients diagnosed with FCD. Cortical specimens from patients who underwent surgical resection of focally dysplastic cortex at Phoenix Children’s Hospital between 2008 and 2014 were examined using immunohistochemistry. Primary antibodies against GFAP and Iba1, as well as structural staining using hematoxylin and eosin (H&E), were incubated on sections and further analyzed using bright‐field microscopy. A pattern of perivascular activated microglia was observed in five patients around at least one blood vessel, while a pattern of non‐localized ramified microglia was observed in the other three patients. No identifiable pattern of astrocytic distribution was found. Thus, distinct patterns of microglia, rather than astrocytes, suggest dual underlying mechanisms of epileptogenesis.
56

Characterizing octagonal and rectangular fibers for MAROON-X

Sutherland, Adam P., Stuermer, Julian, Miller, Katrina R., Seifahrt, Andreas, Bean, Jacob L. 22 July 2016 (has links)
We report on the scrambling performance and focal-ratio-degradation (FRD) of various octagonal and rectangular fibers considered for MAROON-X. Our measurements demonstrate the detrimental effect of thin claddings on the FRD of octagonal and rectangular fibers and that stress induced at the connectors can further increase the FRD. We find that fibers with a thick, round cladding show low FRD. We further demonstrate that the scrambling behavior of non-circular fibers is often complex and introduce a new metric to fully capture non-linear scrambling performance, leading to much lower scrambling gain values than are typically reported in the literature (<1000 compared to 10,000 or more). We find that scrambling gain measurements for small-core, non-circular fibers are often speckle dominated if the fiber is not agitated.
57

Applications of focal-series data in scanning-transmission electron microscopy

Jones, Lewys January 2013 (has links)
Since its development, the scanning transmission electron microscope has rapidly found uses right across the material sciences. Its use of a finely focussed electron probe rastered across samples offers the microscopist a variety of imaging and spectroscopy signals in parallel. These signals are individually intuitive to interpret, and collectively immensely powerful as a research tool. Unsurprisingly then, much attention is concentrated on the optical quality of the electron probes used. The introduction of multi-pole hardware to correct optical distortions has yielded a step-change in imaging performance; now with spherical and other remnant aberrations greatly reduced, larger probe forming apertures are suddenly available. Probes formed by such apertures exhibit a much improved and routinely sub-Angstrom diffraction-limited resolution, as well as a greatly increased probe current for spectroscopic work. The superb fineness of the electron beams and enormous magnifications now achievable make the STEM instrument one of the most sensitive scientific instruments developed by man, and this thesis will deal with two core issues that suddenly become important in this new aberration-corrected era. With this new found sensitivity comes the risk of imaging-distortion from outside influences such as acoustic or mechanical vibrations. These can corrupt the data in an unsatisfactory manner and counter the natural interpretability of the technique. Methods to identify and diagnose this distortion will be discussed, and a new technique developed to restore the corrupted data presented. Secondly, the subtleties of probe-shape in the multi-pole corrected STEM are extensively evaluated via simulation, with the contrast-transfer capabilities across defocus explored in detail. From this investigation a new technique of STEM focal-series reconstruction (FSR) is developed to compensate for the small remnant aberrations that still persist – recovering the sample object function free from any optical distortion. In both cases the methodologies were developed into automated computer codes and example restorations from the two techniques are shown (separately, although in principal the scan-corrected output is compatible with FSR). The performance of these results has been quantified with respect to several factors including; image resolution, signal-noise ratio, sample-drift, low frequency instability, and quantitative image intensity. The techniques developed are offered as practical tools for the microscopist wishing to push the performance of their instrument just that little bit further.
58

Úloha proteinu p130CAS v integrinové signalizaci / The role of p130CAS in integrin signaling

Janoštiak, Radoslav January 2014 (has links)
Focal adhesions are important subcellular structures that are composed of many signaling and scaffolding proteins. They serve not only for anchoring the cell to the substratum but they are also important signaling centers that regulate various cellular behavior such as migration, invasiveness, proliferation and survival. Focal adhesion signaling needs to be strictly regulated because alteration in activity or expression of many focal adhesion proteins leads to tumorogenesis and metastasis formation. One of the most important scaffolding protein associated with focal adhesion is p130Cas. The importance of p130Cas in regulation of cell migration and invasiveness has been well established. P130Cas also plays important role in regulation of cell survival and proliferation. Moreover, high protein levels of human ortholog of p130Cas - BCAR1, has been linked to more aggressive breast tumors and poor prognosis. During my doctoral studies, I focused on the role of p130Cas in integrin signaling. At the beginning we characterized the role of tyrosine 12 phosphorylation within its SH3 domain. We confirmed that this phosphorylation is increased in Src527F transformed mouse embryonic fibroblasts compared to non-transformed counterparts and also in some human cancer cell lines. We showed that this phosphorylation...
59

Likhet inför lagen? : Undermedveten strukturell diskriminering av etniska minoriteter

Kihlberg, Andreas, Myrin, Nicklas January 2016 (has links)
Inledning: Den skapade bilden av att invandrare skulle vara farligare än den infödda populationen i landet riskerar leda till en undermedveten strukturell diskriminering som genomsyrar det västerländska samhället och således även rättssystemet. Tidigare forskning har visat att etniska minoriteter utsatts för negativ särbehandling vid såväl polisens ingripande som vid domstolens beslut. Denna särbehandling kan tänkas leda till en förlust av rättssystemets legitimitet och därmed till en ökad brottslighet i samhället. Som teoretiskt ramverk för problemet användes social conditioning theory och focal concerns theory. Syfte: Att undersöka huruvida det bland svenska juriststudenter förekommer negativ särbehandling av etniska minoriteter. Metod: En enkätstudie genomfördes på totalt 210 juriststudenter från fyra universitet i Sverige. Enkäten bestod av två fallbeskrivningar med åtta frågor till respektive fallbeskrivning. Av urvalet fick 104 studenter läsa om gärningsmän med typiskt skandinaviska namn och 106 studenter fick läsa om gärningsmän med typiskt arabiska namn. Mann Whitney-U test genomfördes mellan respondenterna som läst om skandinaviska respektive arabiska gärningsmän. Därtill undersöktes Spearmans rangkorrelation mellan respondenternas attityder till våldsbrott. Resultat: Vid grov misshandel uppfattades gärningsmannen med arabiskt namn vara farligare för samhället än gärningsmannen med skandinaviskt namn. Vidare fanns tendenser till att respondenterna undermedvetet uppfattade gärningsmannen med arabiskt namn som mer förekommande vid rån än gärningsmannen med skandinaviskt namn. Diskussion: Respondenterna visade tendenser till undermedvetna fördomar om etniska minoriteter, men lät inte dessa fördomar påverka det valda straffet. Resultatet visar att stereotypa fördomar kan finnas på ett undermedvetet plan, vilket torde kunna leda till negativ särbehandling i vissa situationer när det kommer till domstolsfrågor. Resultaten är i linje med tidigare forskning och studiens teoretiska ramverk, men påvisar samtidigt den komplexitet som ligger bakom problemet. / <p>2016-06-01</p>
60

Development of an automated system for the measurement of focal ratio degradation of high numerical aperture fibres

Lee, Jooyoung 07 August 2019 (has links)
The thesis presents the development and testing of an automated fibre optic test system for the measurement of focal ratio degradation (FRD) in high numerical aperture fibres. In particular, the fibres under examination are being proposed for use in the Maunakea Spectroscopic Explorer (MSE), a new telescope currently being designed for wide-field surveys of the night sky. A critical subsystem of the MSE is the Fiber Transmission System (FiTS) that connects the focal plane to the telescope’s spectrographs. In preparation for MSE-FiTS, a method of characterizing the focal ratio degradation (FRD), between the input and output of every fibre, of candidate multi-mode fibres is highly important. The ultimate goal is the testing of all 4,332 fibres after assembly and prior to installation on MSE. An optical bench has been constructed to test the performance of an automated characterization system; a variation on the collimated beam test. Herein we present the underlying analysis FRD measurement method, the optical design of the test bench, the motion control system and the software for measuring FRD, and controlling the automated test system. The open-source automation software is also introduced; the Big FiTS Fibre Wrapper (Big FFW). The results of tests performed using the Big FFW on samples of candidate fibres are presented and compared with the results in the literature using manual methods. The results suggest that the candidate MSE fibre meets the science requirement of less than 5% focal ratio degradation for an f/2 input beam measured at the fibre output. There is less than 1% disagreement between the automated measurement method and manual methods reported in the literature. The fully automated system can measure the FRD of up to 10 fibres in a typical MSE fibre bundle configuration. / Graduate

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