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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.
21

Electroluminescence in conjugated polymers

Greenham, Neil Clement January 1995 (has links)
No description available.
22

Function and significance of ancient Egyptian royal palaces from the Middle Kingdom to the Saite period : a lexicographical study and its possible connection with the archaeological evidence

Pagliari, Giulia January 2012 (has links)
The architectural analysis of archaeologically known royal palaces in Egyptological studies has shown that ancient Egyptian royal palaces with similar setting might have served similar function. The differences recognizable in the few royal structures known from the Middle Kingdom onwards must reflect differences in the conception that was at the basis of their construction and the activities performed within each site. Such architectural variety corresponds to the complexity of the terminology associated with Egyptian palaces. There are at least five terms for “palace” that have been identified in the Egyptian vocabulary - 'h, pr-'3, pr-nswt, h_nw and stp-s3 – the exact meaning of the majority of which needs to be specified. The present lexicographical study aims to understand what each word would have been for by analyzing its use in different contexts: private titles, official inscriptions or literary texts. The final attempt of this work is to identify a possible correspondence between such terminology and the surviving structures. As an example of a possible application of the lexicographical study to the archaeological evidence, the word ‘h, referring in texts to a royal structure with ritual function, might be related to palaces with a tripartite and axial ordering comparable with temples.
23

Excavating paper squeezes : identifying the value of nineteenth and early twentieth century squeezes of ancient Egyptian monuments, through the collections of seven UK archives

Booth, Charlotte January 2018 (has links)
This thesis provides a history of squeeze making in the discipline of Egyptology from its beginnings in the mid-nineteenth century to the continued use of tin squeezes in modern archaeological practice. The difference in approach to squeezes between the Egyptological and the Mediterranean disciplines will also be discussed. The analysis of the on-going value of squeezes produced more than a century ago highlights their importance for conservation and archival work as well as historical interpretation of the monuments of ancient Egypt. Using squeezes from seven archival collections in the UK as case studies, the accompanying catalogue and discussion highlights the information that can be obtained from the study of paper squeezes taken of Egyptian monuments in the nineteenth and early twentieth centuries. The squeezes studied highlight a number of inscriptions which have disappeared or have been extremely damaged since the squeezes were taken, demonstrating the value of these documents in reconstructing the monuments of the past. The overall objective is to encourage scholars to identify the importance these squeezes hold for epigraphic, social and conservation disciplines which acknowledging the damage caused in their production should not define how they are studied (or indeed not studied) in the modern world.
24

The Study of Optoelectronic Characteristics and Charge Generation Mechanism in White Organic Light-Emitting Diode with Tandem Structure

Liu, Chia-Chun 24 August 2011 (has links)
Recently, tandem white organic light-emitting diodes are attracting a great deal of interest due to their potential illumination applications. A tandem structure is a mean two or more electroluminescence units that joined together through connecting units in series. So, we can make sense that the connecting unit has play an important role in this particular structure. In my paper research, the functions of connecting units are usually being considered with two aspects: charge transporting and charge generation. But, it was rarely discussed which function is the key point. Three devices were fabricated in this study : (¢¹) unit device, (¢º) tandem device 1 with connecting layers of Alq3:Li/MoO3 and (¢») tandem device 2 with connecting layers of Alq3:Li/HAT-CN. Base on this two connecting unit structure, we can get a quantifiable data from adopting, carrier transporting and carrier generation and figure out which function of connecting unit in tandem device is the main factor. The unit device has outstanding performance comparing to others fluorescence white OLED. It exhibits a maximum luminance of 49820 cd/m2 at 1755 mA/cm2, the power efficiency of 2.52 lm/W at 20 mA/cm2 and CIE (0.33, 0.33). But the power efficiency decreased to 2.07 lm/W at 20 mA/cm2 in tandem device 1. In order to improve device performance, we choose new material HAT-CN to replace to MoO3. From our result, the tandem device 2 have increase power efficiency from 2.07 lm/W to 2.24 lm/W at 20 mA/cm2, and the maximum luminance reach 71790 cd/m2 at 650 mA/cm2 with CIE(0.30, 0.39). We want to figure out why the power efficiency increased after using HAT-CN in tandem device. So we further designed and fabricated the hole only device, electron only device and capacitance device to figure out the charge transporting and charge generation behavior between these two connecting unit constructed based on Alq3:Li/MoO3 and Alq3:Li/HAT-CN. After analyzing the results of these devices, we found that the charge generating plays a major role in tandem OLED¡¦s performance. In other words, if the more carriers can be generated in the connecting layers, the higher power efficiency in tandem device can be realized.
25

Odtokové poměry vybraného povodí

Štěpánová, Klára January 2016 (has links)
This diploma Thesis deals with the drainage conditions and retention potential of the selected river basin Karlínský creek in the Vysočina Region of a total area 1 722 hectare. The goal of the Thesis is to evaluate hydrological characteristics of the watershed calculated by the DesQ-MAXQ model. The input data are gained by processing of a resource materials in ArcGIS programme. The results as potential retention, volume of runoff and peak flow are presented in the form of map outputs drew up by using ArcGIS programme. An important part of the Thesis is also literary research focused to the topic issue and the characteristic of the river basin of interest.
26

Estimativa da recarga subterrânea em bacia hidrográfica do semiárido pernambucano a partir de técnicas de sensoriamento remoto e sistemas de informações geográficas

COELHO, Victor Hugo Rabelo 03 February 2016 (has links)
Submitted by Isaac Francisco de Souza Dias (isaac.souzadias@ufpe.br) on 2016-07-07T18:03:04Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese_Victor_Versão_Final.pdf: 12070696 bytes, checksum: 5580364541fc1e8bdf9f1bc84dc852fa (MD5) / Made available in DSpace on 2016-07-07T18:03:04Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese_Victor_Versão_Final.pdf: 12070696 bytes, checksum: 5580364541fc1e8bdf9f1bc84dc852fa (MD5) Previous issue date: 2016-02-03 / FACEPE / As limitações de dados pontuais para a estimativa da recarga subterrânea em grandes áreas ainda é um grande desafio para uma boa gestão desse recurso hídrico, principalmente em regiões semiáridas. Por causa da escassez de dados observados, a abordagem desta pesquisa estabelece uma integração entre um conjunto de variáveis do balanço hídrico, obtidas a partir de imagens de satélites, para estimar a distribuição espacial da recarga das águas subterrâneas na bacia hidrográfica do rio Ipanema (BHRI), localizada no estado de Pernambuco, Nordeste do Brasil. Os dados de sensoriamento remoto empregados incluem mapas mensais (2011-2012) de precipitação, escoamento superficial e evapotranspiração, utilizados como entradas para a aplicação do método do balanço hídrico (pixel a pixel) em um Sistema de Informação Geográfica (SIG). A precipitação utilizada foi derivada do satélite TRMM (3B43.v7) e seguiu o mesmo padrão médio mensal observado em 15 estações pluviométricas distribuídas pela área de estudo (CC = 0,93 e REQM = 17,1 mm), com estimativas médias anuais de 894,3 (2011) e 300,7 mm (2012). O escoamento superficial, adquirido pelo método SCS-CN a partir de informações dos solos da região e imagem do sensor TM, foi equivalente a 29% da precipitação registrada pelo TRMM durante os dois anos do estudo. Já a evapotranspiração real, obtida pela aplicação do SEBAL em imagens do sensor MODIS, apresentou valores médios anuais de 1.190 (2011) e 1.072 mm (2012). Os resultados do balanço hídrico mostraram que a recarga subterrânea na BHRI apresentou uma grande diferença interanual, caracterizada pelos regimes pluviométricos distintos, com médias de 28,1 (2011) e 4,9 (2012) mm ano-1. Essas recargas foram concentradas principalmente entre os meses de janeiro a julho nas regiões compostas por sedimentos aluviais e outros solos de alta permeabilidade. As aproximações da recarga subterrânea por sensoriamento remoto foram comparadas ao método WTF (Water Table Fluctuation) em uma área específica de aluvião na BHRI. As estimativas realizadas pelas duas metodologias apresentaram boa concordância anual, com valores médios de 154,6 (WTF) e 120,9 (balanço hídrico) mm em 2011, que correspondem a 14,89 e 13,12% das precipitações registradas pelo pluviômetro e pelo TRMM, respectivamente. Para o ano de 2012, apenas a metodologia WTF registrou uma recarga muito baixa de 15,9 mm. Como os estudos referentes ao tema ainda são incipientes, os valores gerados nesta tese fornecem uma boa percepção do potencial do sensoriamento remoto para avaliar as taxas desse importante componente do balanço hídrico na BHRI. / The limitations of data points to estimate the groundwater recharge over large areas are still a challenge for a good management of water resource, especially in semi-arid regions. Due to the deficiency of observed data, the approach of this research establishes an integration of hydrological cycle variables obtained from satellite images to estimate the spatial distribution of groundwater recharge in the Ipanema basin river (BHRI), located in the Pernambuco state, northeastern of Brazil. The remote sensing data used, which include monthly maps (2011-2012) of rainfall, runoff and evapotranspiration were used as input to apply the water balance method (pixel by pixel) in a Geographic Information System (GIS). The rainfall used was derived from the TRMM satellite (3B43.v7) and has the same monthly average observed temporal distribution in 15 rain gauges distributed over the study area (CC = 0.93 and RMSE = 17.1 mm), with annual average estimates of 894.3 (2011) and 300.7 mm (2012). The runoff acquired by SCS-CN method from information soil of the region and TM sensor image was equivalent to 29% of the TRMM rainfall registered during the two years of the study. The actual evapotranspiration obtained by the SEBAL application in MODIS images presented annual average of 1,190 (2011) and 1,072 (2012) mm. The results of the water balance showed a large interannual difference in the BHRI groundwater recharge, characterized by different rainfall regimes with averages of 28.1 (2011) and 4.9 (2012) mm year-1. These recharges were mainly concentrated between January to July in the regions with alluvial sediments and others high permeability soils. The groundwater recharge approach by remote sensing was compared to the WTF method (Water Table Fluctuation) in a specific area of alluvium in the BHRI. The estimates performed by the two methods showed good annual agreement, with mean values of 154.6 (WTF) and 120.9 (water balance) mm in 2011, corresponding to 14.89 and 13.12% of rainfall recorded at the rain gauge and TRMM, respectively. For the second year, just WTF method recorded a very low recharge of 15.9 mm. Studies related to the groundwater recharge involving remote sensing are incipient and the values generated in this thesis provide a good perception of the methodology to evaluate the rates of this important component of the water balance in the BHRI.
27

Vliv uspořádání krajiny na erozní a odtokové poměry v k.ú. Stará Ves u Bílovce / Influence of landscape structure on the runoff and erosion condition in Stará Ves u Bílovce

Lízalová, Zuzana January 2014 (has links)
This thesis deals with the influence of the landscape structure on the erosion and runoff conditions. The aim of the thesis is to analyze the erosion and runoff conditions of the landscape in the area of Stará Ves by Bílovec for three different time periods and for the design condition. The thesis is divided into four parts, the first part is theoretical, dealing with erosion and runoff conditions in the form of research. The second part analyzes the current state of the area. The third part of the thesis defines and evaluates the erosion wash off and runoff condiditons for given variations. The last part deals with the development of the land use from 1957 to the present.
28

Analýza odtokových poměrů ve vybraném povodí

Dufek, Václav January 2018 (has links)
The diploma thesis analyzes and evaluates the drainage conditions together with the retention potential of the landscape in the parts of the Bělský potok basin, which is located in the south of the Pardubice Region. The theoretical part of the thesis contains the elaborated literary research on the basis of the study of the specialized literature mentioned on the given issue, and also the characterization of the selected river basin. The practical part includes processing of underlying materials and data preparation in ArcGIS 10.3.1 using the ArcMap, ArcCatalog and ArcToolbox integrated applications suite. Processed data are the input information for the calculation of hydrological characteristics by the DesQ-MAXQ model.The resulting calculated values of maximum flows, specific flows, potential retention in the basin, concentration time, amount of water retained for each sub-basin are presented in the form of map outputs.
29

Células tándem fotoelectroquímicas para la generación de hidrógeno y otros combustibles solares

Díaz-García, Ana Korina 25 September 2017 (has links)
Esta tesis tiene como objetivo el diseño de una célula tándem fotoelectroquímica estable para la generación de hidrógeno y otros combustibles solares. Para ello se investiga la factibilidad de diferentes materiales, tales como el CuCrO2 y el CN el para su aplicación como fotocátodos y WO3 para su aplicación como fotoánodo.
30

Neuartige Tricyanoborate der Tetrelgruppe -und- Poly- und Ionomere mit Tricyanoboraten / Novel Tricyanoborates of the Tetrel Group -and- Poly- and Ionomers with Tricyanoborates

Häring, Mathias January 2022 (has links) (PDF)
Diese Arbeit beschäfftig sich mit der Synthese und Charakterisierung neuartiger Tricyanoborate der Hauptgruppe 4, sowie der Synthese und Charakterisierung neuartiger Polymere mit Tricyanoboratgruppen. / This work deals with the synthesis and characterization of novel tricyanoborates of the main group 4 together with the synthesis and characterization of novel polymers with tricyanoborate groups.

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