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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.
161

Radverkehr im Ausnahmezustand: Mit Rückenwind aus der Krise?: Schwerpunktthema Internetportal zum Nationalen Radverkehrsplan - Fahrradportal

Stein, Thomas, Köhler, Dagmar 11 November 2022 (has links)
No description available.
162

Parentage Statements and Paired Stelae: Signs of Dynastic Succession for the Classic Maya

Stewart, Daniel Moroni 22 December 2008 (has links) (PDF)
The purpose of this thesis is to describe and document parentage statements and paired stela found on Maya monuments or portable objects. While the existence of parentage statements, within the Maya text, has been known since the late 1970s, no thesis or major research project has ever been published pertaining to this class of glyphs within the Maya script. In 1977 Christopher Jones is credited with the discovery of parentage statements in Maya hieroglyphic texts (Jones 1977). His discovery was followed by a detailed analysis of parentage statements by Floyd Lounsbury, Peter Mathews, and Linda Schele (1977). They introduced most of the known parentage statements and detailed their use in the hieroglyphic texts. While their work, which introduced parentage statements, in general, is cited regularly as the all-encompassing source of information about parentage statements, it remains unpublished. This thesis provides a source for all new and previous work done on parentage statements and insight into possibly why parentage statements were used by the Classic Maya. An analysis of 253 archaeological sites containing a total of 2473 glyphic monuments was conducted as part of this thesis. Justin Kerr's online vase and photo collections were also checked for parentage statements on portable objects and ceramic vessels. Parentage statements were found on 225 monuments and 70 portable objects bringing the total to 295 different monuments with parentage statements. Each parentage statement is identified and transcribed phonetically. The usage of each parentage statement and its variants are then mapped through time. Also introduced in this thesis is the death of a parent glyph commonly known as the Winged Capped Ajaw Death Phrase. An analysis of its usage demonstrates that it refers to the death of a parent. Paired stelae were analyzed as another possible form of parentage statements. This thesis tests three hypotheses on why parentage statements were used. They included ancestor worship, political legitimacy, and heir designation. The weaknesses and strengths of each hypothesis are demonstrated through case studies. Lastly, the appendices include source material for each site and monument researched as part of this thesis.
163

Vertragsrecht in der Coronakrise: Online-Tagung im April 2020

Effer-Uhe, Daniel, Mohnert, Alica 27 January 2023 (has links)
Der Ausbruch der Coronakrise verunsichert, aber Verträge sind in der Welt. Was hat Bestand, was bedarf der Anpassung? Der Tagungsband dokumentiert die Beiträge der Online-Tagung „Vertragsrecht in der Coronakrise“ in zitationsfähiger Form. Von grundlegenden dogmatischen Aspekten wie dem allgemeinen Leistungsstörungsrecht über das massenhaft relevante Verbraucher- sowie Mietrecht bis hin zu Spezialfragen in der Insolvenz beantworten Rechtsexperten die drängenden Fragen in der Pandemie, z.B. Wer trägt die Hotelkosten, wenn ein Pauschalreisender wegen Flugausfällen an der Rückreise gehindert ist? Können Arbeitnehmer auf erhöhte Schutzvorkehrungen im Betrieb pochen? Wer haftet, wenn eine Warenlieferung an der Landesgrenze durch überlange Kontrollen verspätet eintrifft oder zwischenzeitlich verdirbt? Herausgegeben von PD Dr. Daniel Effer-Uhe und Dipl.-Psych. Alica Mohnert, Mag. iur., LL.M. (CUPL). Mit Beiträgen von Dr. Caspar Behme, Ludwig-Maximilians-Universität München; Dr. Jonas Brinkmann, Universität Bielefeld; Dr. Ann-Marie Kaulbach, Universität zu Köln; Stephan Klawitter, Humboldt-Universität zu Berlin; Jun.-Prof. Dr. Andreas Maurer, Universität Mannheim; PD Dr. Patrick Meier, Notarassessor, Julius-Maximilians-Universität Würzburg; Jun.-Prof. Dr. Jens Prütting, Rechtsanwalt, Bucerius Law School Hamburg; Prof. Dr. Thomas Riehm, Universität Passau; Prof. Dr. Jens M. Schmittmann, Rechtsanwalt, Mitglied des Senats für Anwaltssachen des Bundesgerichtshofs, FOM Hochschule Essen; Dipl.-Kfm. Dr. Bernd Scholl, Rechtsanwalt, Universität zu Köln.
164

Vikariers påverkan på förskollärares psykosociala arbetsmiljö / The impact of substitutes on preschool teachers psychosocial work environment

Kruse, Camilla, Oregren, Helena January 2022 (has links)
Syftet med studien är att få en djupare förståelse i förskollärares upplevelse av deras psykosociala arbetsmiljö i samband med ett omfattande behov av vikarieanvändning. Frågeställningarna lyder: Hur påverkar vikarier förskollärares psykosociala arbetsmiljö? Hur upplever förskollärarna rektorernas stöd, kopplat till vikariers påverkan? Hur har coronapandemin påverkat nyttjandet av vikarier och förskollärares psykosociala arbetsmiljö? Studien berör aspekter kring psykosocial arbetsmiljö, risker och stressorer kopplat till hälsa och ohälsa. Ledarskapsteori omfattande rektorers inverkan, lagar och läroplan kopplat till förskolan och vikarier. Följt av coronapandemins påverkan på vikarieanvändningen och förskollärarnas utförande av yrkesuppdraget. Empiriskt underlag hämtades från kvalitativa semistrukturerade intervjuer med nio förskollärare från olika förskoleverksamheter i Värmland. Insamlat material ligger till grund för studiens analys och resultat, vilket har kodats och analyserats enligt grundad teori. Studiens resultat visar att förskollärarnas psykosociala arbetsmiljö påverkas negativt i samband med en hög vikarieanvändning. Graden av påverkan baseras på om vikarierna var kända eller okända, samt på vikariernas erfarenhet, kompetens och personlighet. Rutiner och förutsättningar för sjukfrånvaro var också en stor påverkansfaktor, samt hur tydligt dessa förankrats mellan rektor och förskollärarna. Störst inverkan på förskollärarnas arbetsmiljö hade förskollärarnas kollegor, vilka la grunden för deras möjlighet till planering, utförande, återhämtning och socialt stöd i arbetet. Vid frånvaro av ordinarie personal fanns risk att förlora detta, vilket ledde till ökad stress och arbetsbelastning hos förskollärarna. Cornapandemin visade sig ha resulterat i en ökad sjukfrånvaro och därmed ett ökat behov av vikarier, vilket kunde leda till problematiken att vikarierna tog slut.
165

Coronite Amphibolites from the Whitestone Area, Parry Sound, Ontario

Mummery, Robert 12 1900 (has links)
<p> Coronite amphibolites located near the western contact of the. Whitestone Lake Anorthosite were studied in the field and laboratory in order to determine their origin. The corona textures consisted of garnet cores surrounded by complete rims of plagioclase, which in turn were occasionally surrounded by partial or complete rims of garnet or pyroxene. The development of coronas is also accompanied by an increase in pyroxene in the rock, and the development of cryptic zoning in both garnets and plagioclases. Whole rock X-Ray Fluorescence and mineral electron-probe analyses were determined for suites of samples collected. The analyses suggest that corona development occurred isochemically as the result of a contact metamorphism induced by anorthosite emplacement and mineral reactions have been proposed. Microprobe analyses of the garnets led to the establishment of models for the production of garnets in mafic assemblages and models for the observed cryptic zoning in the garnets~ It was concluded that the coronites represent the transition from almandine amphibolite facies to clinopyroxene subfacies of granulite metamorphism of garnetiferous amphibolites. This transition results from the thermal metamorphism induced by the emplacement of the Whitestone lake anorthosite. </p> / Thesis / Doctor of Philosophy (PhD)
166

Surface treatment of polyethylene in electrical discharges

Stradal, Milos January 1974 (has links)
Note:
167

Entre Castilla, la Corona de Aragón y el Mediterráneo: la formación de un mercado transnacional en el reino de Valencia durante la Baja Edad Media

Crespo Amat, Carlos 30 September 2021 (has links)
A lo largo de los dos últimos siglos de la Edad Media, se desarrollaron en gran parte de Europa tres procesos cuyos efectos en Castilla y la Corona de Aragón tuvieron un punto de convergencia en el espacio transfronterizo que conforma el reino de Valencia entre el interior peninsular y el Mediterráneo a partir del último cuarto del siglo XIV (cuando pudieron estabilizarse las relaciones internacionales entre ambas coronas): en primer lugar, la formación del Estado y el afianzamiento de instituciones y marcos jurídico-normativos; en segundo lugar, la consolidación de los mercados interiores y la jerarquización de los circuitos económicos exteriores; y, en tercer lugar, el incremento de las circulaciones de personas, bienes, capitales y servicios y el desarrollo de instrumentos y estrategias mercantiles precapitalistas. La conjunción de los distintos fenómenos políticos y económicos implicados en tal desarrollo dio lugar, hacia mediados del siglo XV, a un panorama caracterizado por el éxito de dos estados bien organizados y complejos institucionalmente y a unos centros económicos interiores y marítimos consolidados como polos mercantiles, industriales y/o financieros a escala suprarregional o internacional. Con esa evolución como trasfondo, la hipótesis de partida es que una parte sustancial del proceso descrito tuvo como base, en el escenario ibérico, las relaciones bidireccionales político-económicas establecidas entre los espacios interiores castellanos y el reino de Valencia. La tesis doctoral es, así, un análisis de la configuración y consolidación del mercado transnacional que se concretó en el espacio económico castellano-valenciano-mediterráneo durante las tres décadas finales siglo XIV y los tres primeros decenios del XV. En última instancia, pretende valorar la aportación del fenómeno investigado al desarrollo del sistema de intercambios peninsular sobre el que se cimentó un sector importante del modelo económico hispánico durante la Edad Moderna. El estudio se divide en dos partes. La primera de ellas cuenta con cinco capítulos en los que se analizan los fundamentos político-fiscales de la construcción del mercado transnacional valenciano. En el primer capítulo se precisan las competencias de las principales instituciones políticas de las coronas de Castilla y Aragón en la regulación de los intercambios económicos y los tráficos mercantiles. El segundo capítulo profundiza en el desarrollo de las instituciones judiciales mercantiles implicadas en el comercio castellano y catalano-aragonés, prestando una atención especial a la juraduría de los mercaderes y a los dos conatos de fundación de un consulado castellano en València. En el tercer capítulo se describen los principales escenarios de los contactos económicos mantenidos dentro del espacio definido y su relevancia en el sistema mercantil del sector occidental de la Península Ibérica. El cuarto capítulo es un análisis de las líneas centrales de intervención de las Monarquías castellana y aragonesa en materia de política monetaria, así como de sus implicaciones en el comercio interior y exterior. En el quinto capítulo se aborda un examen detallado del principal componente fiscal de las relaciones político-económicas castellano-aragonesas, la quema, y específicamente castellano-valencianas, el dret dels damnificats. La segunda parte comprende un estudio pormenorizado de las fases identificadas en el proceso de construcción del mercado transnacional valenciano entre 1370 y 1430. En el capítulo sexto, que es el primero de este bloque, se analizan las bases político-diplomáticas sobre las que se asentó el sistema de intercambios castellano-aragonés instaurado tras el fin de la guerra de los Dos Pedros en 1369 y el interés de los operadores locales y extranjeros en el espacio económico castellano-valenciano. En el séptimo capítulo se profundiza en las causas que condujeron a un cambio de signo en las relaciones internacionales entre Castilla y la Corona de Aragón durante la última década del siglo XIV y los primeros años del siglo XV y se exponen las principales implicaciones del paralelo auge económico que se vivió en los contactos mercantiles entre ambos estados. El octavo capítulo está dedicado íntegramente a la investigación de la coyuntura de ruptura comercial que atravesaron las relaciones económicas castellano-aragonesas entre 1403 y 1409, así como de las soluciones encontradas en un territorio y en otro para mantener, bajo mínimos, el sistema mercantil consolidado tras el fin de la guerra. Finalmente, en el noveno capítulo se exponen las principales manifestaciones de las crisis sufridas en el escenario político peninsular y sus –en general, pocos– efectos en el proceso de expansión y jerarquización de los circuitos comerciales transnacionales que se experimentó en el espacio económico castellano-valenciano-mediterráneo durante la segunda y la tercera década del siglo XV. / Esta tesis doctoral ha sido financiada con una ayuda a la Formación de Profesorado Universitario concedida por el Ministerio de Universidades en el marco del Programa Estatal de Promoción del Talento y su Empleabilidad en I+D, Subprograma Estatal de Formación, con referencia FPU15/00157.
168

Corona switching: an osmogene mitigation technique

Atkinson, R. Dwight January 1988 (has links)
Odorous gases such as hydrogen sulfide have long been associated with wastewater treatment plants, especially those with long forced mains which allow septic conditions to develop. With the encroachment of urban and suburban populations, many wastewater treatment plants are no longer located far enough from residential areas to prevent odor problems. This has lead to renewed efforts to develop odor control techniques. The application of high energy coronas as a means to oxidize odorous gases has been limited by the relatively small size of the corona region around a given charged wire, approximately 1 centimeter at an applied voltage of 35 kilovolts. Attempts to enlarge the effective corona region by spacing wires such that their coronas would overlap have failed due to corona extinction, the destructive interference of the electric fields surrounding adjacent charged wires. This study demonstrates that corona extinction can be avoided in a system of closely spaced wires flanked by grounded plates if the wires are energized individually instead of' simultaneously. By employing a rapid load-switching technique an essentially continuous corona sheet can be produced. A bench-scale device utilizing the rapid switching principle was constructed and its ability to remove odorous gases, including hydrogen sulfide, was demonstrated. The influence of parameters such as flowrate, inlet concentration, switching frequency, temperature, and humidity on removal efficiency was evaluated. / Ph. D. / incomplete_metadata
169

On the topology of global coronal magnetic fields

Edwards, Sarah J. January 2014 (has links)
This thesis considers the magnetic topology of the global solar corona. To understand the magnetic topology we use the magnetic skeleton which provides us with a robust description of the magnetic field. To do this we use a Potential Field model extrapolated from observations of the photospheric magnetic field. Various measurements of the photospheric magnetic field are used from both ground-based observatories (Kitt-Peak and SOLIS) and space-based observatories (MDI and HMI). Using the magnetic skeleton we characterise particular topological structures and discuss their variations throughout the solar cycle. We find that, from the topology, there are two types of solar minimum magnetic field and one type of solar maximum. The global structure of the coronal magnetic field depends on the relative strengths of the polar fields and the low-latitude fields. During a strong solar dipole minimum the heliospheric current sheet sits near the equator and the heliospheric current sheet curtains enclose a large amount of mixed polarity field which is associated with many low-altitude null points. In a weak solar dipole minimum the heliospheric current sheet becomes warped and large scale topological features can form that are associated with weak magnetic field regions. At solar maximum the heliospheric current sheet is highly warped and there are more null points at high altitudes than at solar minimum. The number of null points in a magnetic field can be seen as a measure of the complexity of the field so this is investigated. We find that the number of nulls above 10Mm falls off with height as a power law whose slope depends on the phase of the solar cycle. We compare the magnetic topology we found at particular times with observations of the Doppler velocity and intensity around particular active regions to see if it is possible to determine whether plasma upflows at the edge of active regions are linked to open field regions.
170

Effect of structuring on coronal loop oscillations

McEwan, Michael P. January 2007 (has links)
In this Thesis the theoretical understanding of oscillations in coronal structures is developed. In particular, coronal loops are modelled as magnetic slabs of plasma. The effect of introducing inhomogeneities on the frequency of oscillation is studied. Current observations indicate the existence of magnetohydrodynamic (MHD) modes in the corona, so there is room for improved modelling of these modes to understand the physical processes more completely. One application of the oscillations, on which this Thesis concentrates, is coronal seismology. Here, the improved theoretical models are applied to observed instances of coronal MHD waves with the aim of determining information regarding the medium in which these waves propagate. In Chapter two, the effect of gravity on the frequency of the longitudinal slow MHD mode is considered. A thin, vertical coronal slab of magnetised plasma, with gravity acting along the longitudinal axis of the slab is studied, and the effect on the frequency of oscillation for the uniform, stratified and structured cases is addressed. In particular, an isothermal plasma, a two-layer plasma and a plasma with a linear temperature profile are studied. Here, a thin coronal loop, with its footpoints embedded in the chromosphere-photosphere is modelled, and the effects introduced by both gravity and the structuring of density at the footpoint layers are studied. In this case, gravity increases the frequency of oscillation and causes amplification of the eigenfunctions by stratification. Furthermore, density enhancements at the footpoints cause a decrease in the oscillating frequency, and can inhibit wave propagation, depending on the parameter regime. In Chapter three, the effects introduced to the transverse fast MHD mode when gravity acts across a thin coronal slab of magnetised plasma are considered. This study concentrates on the modification of the frequency due to the dynamical effect of gravity in the equation of motion, neglecting the effect of stratification. Here, gravity causes a reduction of the oscillating frequency of the fundamental fast mode, and increases the lower cutoff frequency. In effect, for this configuration, gravity allows the transition between body and surface modes, in a slab geometry. It is found, in these two studies, that each harmonic is affected in a unique manner due to structuring or stratification of density. With this knowledge, in Chapter four, a new parameter is derived; P1/2P2, the ratio of the period of the fundamental harmonic of oscillation to twice the period of its first harmonic. This parameter is shown to be a measure of the longitudinal structuring of density along a coronal loop, and the departure of this ratio from unity can yield information regarding the lengthscales of the structure. This process is highlighted using the known observations, indicating that P1/2P2 may prove to be a useful diagnostic tool for coronal seismology. Finally, in Chapter five, outwardly propagating coronal slow MHD modes are observed and are used to infer coronal parameters. The possibility of using these oscillations to infer near-resolution lengthscales in coronal loops -- fine-scale strands -- is also discussed. TRACE observations are used to determine the average period, phase speed, detection length, amplitude and energy flux for the propagating slow MHD mode. The indication is that the source of these oscillations appears very localised in space, and the driver only acts for a few periods, suggesting the perturbations are driven by leaky p-modes (solar surface modes).

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