PERCEPÇÕES NO ENSINO SUPERIOR A DISTÂNCIA: UMA ANÁLISE DO CURSO DE ADMINISTRAÇÃO EM UMA UNIVERSIDADE VIRTUAL NO RS

A educação a distancia com o auxilio da evolução das Tecnologias da Informação e Comunicação, principalmente associadas ao uso da internet, proporcionaram novos espaços de ensino e aprendizagem, rompendo fortemente com as limitações geográficas de atuação das Instituições de Ensino Superior. Estes novos espaços contribuem para formação de diferentes perfis. Logo, surgem diversos questionamentos: Qual o perfil sócio-econômico destas pessoas? Quais suas percepções sobre o ensino a distancia? Quais as motivações que os levaram a escolher por esta modalidade? Este trabalho tem por objetivo investigar alguns destes questionamentos, como objeto de estudo foi feito uma pesquisa em uma universidade de grande porte nesta modalidade, que atua em todo o país, como escopo da pesquisa optou-se pela atuação desta IES na metade Sul do Rio Grande do Sul, mais precisamente nas cidades de Pelotas e Rio Grande, geograficamente distantes aproximadamente 60 Km

The Goldilocks principle in action: synthesis and structural characterization of a novel {Cu4(\u3bc3-OH)4} cubane stabilized by monodentate ligands

A {Cu4(\u3bc3-OH)4} compound, where four copper(II) and four \u3bc3-bridging oxygen atoms occupy alternate corners of a slightly distorted cube, has been prepared and structurally characterized. This species, formulated as [Cu4(\u3bc3-OH)4(Htmpz)8](ClO4)4\ub71.5Et2O (Htmpz = 3,4,5-1H-trimethyl pyrazole), can be classified as belonging to type I Cu4O4 cubane complexes, and is better described as two CuII\u2013(\u3bc-OH)2\u2013CuII units held together by four long Cu\u2013O bonds. The central distorted cubane core is stabilized by neutral monodentate ligands (Htmpz) and perchlorate anions, as demonstrated by single-crystal X-ray structure analysis. The title compound was obtained by hydrolysis of a dinuclear methoxo-bridged species, [Cu(\u3bc-OCH3)(Htmpz)2]2(ClO4)2, which was prepared by reaction of [Cu(Htmpz)4(ClO4)2] with methanol. All these reactions represent a nice example of the Goldilocks principle in action in coordination chemistry, since each single actor (solvent, counteranion, and ligand) has the \u201cjust right\u201d electronic, steric or coordinative properties which determine the fate of the final products

Exploiting supramolecular interactions for asymmetric catalysis.

Supramolecular chemistry refers to the area of chemistry beyond the molecules and focuses on the chemical systems made up of a discrete number of assembled molecular subunits or components. While traditional chemistry concentrates on the covalent bond, supramolecular chemistry examines the weaker and reversible non-covalent interactions between molecules. These forces include hydrogen bonding, metal coordination, hydrophobic forces, van der Waals forces, pi-pi interactions and electrostatic effects. The aim of this thesis is the use of this type of interactions, in particular hydrogen bonding, for the development of new catalytic systems. In the first part of the work the synthesis of a new class of supramolecular bis(oxazolines) named SupraBox using urea moiety as self-assembly inducer is reported. A library of 16 ligands, with different degree of structural diversity, were prepared by a 3-step modular synthesis starting from readily available starting materials. Palladium- and Copper-complexes were characterized by NMR spectroscopy, UV spectroscopy and mass spectrometry to investigate their structures and properties and used as catalysts in kinetic resolutions of racemic diols and in the desymmetrization of meso diols with good results. In the second part, a new class of peptidomimetic organocatalysts starting from two bifunctional diketopiperazines was investigated. Four different organocatalysts were prepared and tested in the conjugate addition reaction of several aldehydes to beta-nitrostyrene and (E)-2-(furan-2-yl)nitroethene with good to excellent diastereo- and enantioselectivities. A rationale for the mechanism is also proposed: a Monte Carlo/Energy Minimization (MC/EM) conformational search by molecular mechanics methods was undertaken on the four catalysts proving the importance of hydrogen bonding between catalyst and substrate

Thermal bridges

This thesis presents the thermal bridge as a "serious problem in the building envelope" where the heat insulation layer is often broken, wet or otherwise damaged which often happens as a result of poorly designed details in wall protrusions (balconies, terraces, bridge elements ....), overhangs, pillars, metal connecting elements, poorly sealed doors and windows, etc. Goal of the thesis is a theoretical identification of the thermal bridge phenomena and a presentation of real-time object thermography which enables us an excellent overview of the object in question. \ud The first thesis chapters describe mechanics of heat transfer through the structural assembly, present thermal bridge phenomena, crossings (potential thermal bridge spots), consequences of thermal bridges and treatment of thermal bridges by international standards. In later chapters I am presenting thermography and methods to analyse anomalies using infrared method and analytically consider thermographic recordings of the measured object/building which pinpoints the spots of particular interest and possible problems. FLIR S65 was utilised to capture thermal recordings which were further processed with ThermaCAMResearcherPro 2.9 software tool. Based on results of thermogram analysis possible damaging effects or thermal bridge consequences were observed. Thermal bridge consequences were considered both in terms of energy efficiency (increased heat flow) and from the standpoint of comfort in living room (decreasing surface temperature).\u

Publication of study materials on convenient computing devices

The thesis deals with the publication and use of advanced electronic study materials on convenient computing devices (Android, iOS). It deals with and compares Android and iOS\ud ecosystems to be used for educational purposes and shows the use of the Tablet PC as a basic student's tool. It shows guidelines for using tablet computers at universities abroad as well as making and publication of a lecture in the largest catalogue of educational themes, iTunes

Solid-State Imaging in Standard CMOS Processes

The main aim of this work is to investigate the real CMOS imaging possibilities of standard (not CMOS imaging enhanced) 0.5µm and 0.35µm CMOS processes available for in-house fabrication at the Fraunhofer IMS by performing an extensive study of standard available photodetector structures, mainly based on reverse biased p-n junctions and/or metal-oxide-semiconductor capacitors (MOS-C). Moreover, novel concepts of photodetector pixel structures and readout circuits are proposed, modelled, simulated, fabricated, and characterised, that should achieve an improvement in performance as well as new application developments in the area of CMOS imaging systems. The latter, undergoing as a small amount of changes (extra masks, thermal steps, ion implantations, etc.) as possible within the standard CMOS processes mentioned. In this sense, in Chapter 1 a brief review of the fundamentals of silicon oriented photodetection and electronic devices physics is given, some of the basic postulates of which are directly applied to the case of the 0.5µm standard CMOS process available at the Fraunhofer IMS, whose photodetection possibilities are investigated in detail in Chapter 2. Chapter 3 deals with different pixel configuration possibilities to be fabricated in the 0.5µm process. As a potential solution to overcome some of the problems encountered in Chapter 3, in Chapter 4, the possibilities of using separated photoactive and readout regions in a mixed silicon-on-insulator (SOI) based high-voltage CMOS process developed for automotive industry applications are discussed. Moreover, the same 30V thin-film SOI CMOS process is proposed for direct (not using a scintillator material) X-ray scientific CMOS imaging applications, as it is explained in Chapter 5. In Chapter 6, the photodetection possibilities of the recently developed 0.35µm standard CMOS process available at the Fraunhofer IMS are investigated, as well as different pixel configurations possible to be fabricated in this process. Finally, a discussion is carried out regarding the results obtained throughout the enlisted chapters, and new lines of investigation are attempted to be opened based on some of the results obtained in the present investigation.Das Hauptthema dieser Dissertation ist die Untersuchung vorhandener und neuer Photodetektoren für die CMOS-Bildsensorik, insbesondere in Bezug auf die technologischen und optoelektronischen Eigenschaften sowie das Rauschen. Durch die gründliche Charakterisierung vorhandener und neuer Photodetektoren und deren Ausleseschaltungen, hergestellt in den 0,5µm, 0,35µm und 1,0µm SOI Standard CMOS Prozessen, wurde das vorhandene Wissen vertieft und erweitert. Auf dieser Basis wurden neue Bauelemente für die 2D- und 3D-Bildsensorik entworfen und bereits vorhandene optimiert. Zum besseren Verständnis der Bauelementenstruktur, und um die Anzahl von Fertigungsdurchläufen für neuartige Photodetektorbauelementen zu reduzieren, wurde die Prozess- und Bauelemente-Simulationsumgebung (ISE-Synopsys) TCAD genutzt. Ziel dabei war es, neu entwickelte Bauelemente vor einer Fertigung bezüglich ihrer Schlüsselspezifikationen zu optimieren und qualitativ bewerten zu können. Ferner wurden passende Ausleseschaltungen für die Photodetektorbauelemente entwickelt. Somit konnte ein System aus Photodetektor und Ausleseschaltung optimal auf eine Anwendung abgestimmt werden. Um die Entwurfsicherheit von CMOS Photodetektoren und Ausleseschaltungen zu erhöhen, wurde zur Modellierung von Photodetektorbauelementen mit den Softwarepaketen MAPLE und Fortran eine Entwicklungsumgebung aufgebaut. Auf Basis der so gewonnenen Spezifikationen der Photodetektorstrukturen konnten die gesamten Pixel mit der Schaltungsentwicklungsumgebung CADENCE simuliert werden. Anschließend wurden diese Detektoren und Ausleseschaltungen in den 0,5µm und 0,35µm Standard CMOS Prozessen sowie in dem 1,0µm SOI CMOS Prozess hergestellt und getestet. Um das Signal-Rausch-Verhältnis (SNR) zu verbessern, wurden verschiedenen Pixelkonfigurationen mit voneinander getrennten Photoaktiv- und Auslesegebieten untersucht, wie z.B. in den „Photogate“- oder „Buried-Photodiode“ Aktiv Pixelsensoren. Es wurde allerdings gezeigt, dass die Ladungskopplung, die für die Auslese bei solchen Pixel notwendig ist, bei keiner Kombination der Photodetektoren und der Auslesegebiete im 0,5µm Standard CMOS Prozess funktioniert. Anschließend wurden Untersuchungen von unterschiedlichen Pixelalternativen mit innovativen Ausleseprinzipien durchgeführt. Eines der neu entwickelten Ausleseprinzipien wurde am „Charge-Injection-Photogate-Pixel“ getestet. Durch dieses Ausleseprinzip entsteht eine große interne Verstärkung. Danach wurde dieses Ausleseprinzip auf einer SOI-Struktur angewendet. Dabei werden alle Vorteile eines Hochspannungs- und Hochtemperaturprozesses zusammen mit den Möglichkeiten genutzt, die ein Standard CMOS Prozess zur Integration der Ausleseelektronik auf dem selben Chip erlaubt. Im Rahmen dieser Dissertation wurde darüber hinaus die Möglichkeit untersucht, die Indium-Zinn-Oxid (ITO) Schichten im 0,5µm Standard CMOS Prozess als Gate-Material einzusetzen. Dies bewirkt einen höheren Quantumwirkungsgrad im sichtbaren Wellenlängenbereich, wenn es bei Photogate-Pixel angewandt wird. Im Nah-Infrarot Wellenlängenbereich jedoch bringt es keine Vorteile gegenüber dem standardmäßig verwendeten Polysilizium. Anschließend wurden verschiedene Pixelstrukturen im 0,35µm Standard CMOS Prozess entworfen und simuliert. Dabei wurde gezeigt, dass zumindest theoretisch das Ladungskopplungsprinzip bei den auf „Photogates“ und auf „Buried-Photodioden“ basierenden Strukturen funktioniert

Contributo alla conoscenza floristica dei licheni italiani: Florula Lichenica del tratto costiero adriatico salentino Torre Rinalda - Le Cesine (Le)

EnIn this work the first results of a lichenological survey in the coastal area between Torre Rinalda and "Le Cesine" (Lecce-South Italy) are eported. Altogether in this area 74 species have been listed, prevalently temperate-mediterranean taxa. The presence of genus Parmotrema (P. chinense, P. hypoleucinum, P. eticulatum) shows that this taxon is not confined along the Tyrrenian coast, where it is common.Particularly, P. hypoleucinum is very abundant and luxuriant in the sheltered area "Le Cesine", a humid zone of international importance, maybe owing to the microclimatic conditions (high humidity, chill Balkan winds)

Contributo alla conoscenza floristica dei licheni italiani: Florula lichenica della costa di Nardò e Porto Cesareo-LE

EnHere is a report about the results of a lichenological survey in the coastal area between Torre Inserraglio and Punta Prosciutto (Lecce-South-East Italy). Altogether in this area 46 species have been found on three substrata: a) rock; b) soil; c) bark. Though the research considers only a part of taxa presents inside the area, it shows some important data: - Prevalence of crusty lichens, mostly on rocky substratum; - Absence of sub-oceanic species like Parmotrema hypoleucinum (Steiner) Hale, which is present along Salentine Adriatic coast; - High lichenic biodiversity of "Palude del Capitano", "Spunnulate di T.rre Castiglione", "macchie di Arneo"

Optimización de los inventarios de efectivo en cajeros automáticos del sistema bancario en la ciudad de Guayaquil.

La red de cajeros automáticos es un importante canal de atención al público, que demanda procesos especializados y sofisticados, implica una importante inversión por parte del sistema financiero del país, mantener operativo y eficiente este canal, representa un reto en el cual participan varios actores como el control y administración de los inventarios de efectivo en los cajeros automáticos, que están fuera de oficinas, denominadas “islas”, para lo cual se propone una metodología. Se evalúa un grupo de cajeros automáticos con la propuesta para el establecimiento de cupos de inventario máximo, mínimo y de seguridad para el abastecimiento de dinero. Siendo esta actividad la primera a realizarse, con cualquier modelo futuro de predicción de la demanda. Para esta investigación se acudió a fuentes primarias y secundarias para la guía de secuencia de pasos y evaluar el comparativo de la simulación de datos, para determinar si existen o no mejoras. El resultado final muestra optimizaciones en todos los cajeros automáticos evaluados. una vez aplicada la metodología para el control de inventarios de efectivo en los cajeros automáticos