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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.
1

Measurement of the Top Quark Mass with Neural Networks

Sánchez, Carlos Andrés 20 December 2002 (has links)
No description available.
2

Utformning av roll-top lock till bordsvärmare

Eklund, Annelie January 2008 (has links)
<p>Detta examensarbete är avslutningen på civilingenjörsutbildningen på Mälardalens högskola. I arbetet används de kunskaper som förvärvats under utbildningen genom att utveckla en produkt åt företaget Idesta i Eskilstuna.</p><p> </p><p>Uppgiften var att utveckla ett lock av typen roll-top lock till Idestas bordsvärmare. Bordsvärmaren används till att varmhålla mat på bland annat restauranger och locket behövs för att skydda maten från omgivningen och hålla maten fräsch.  Målet var att göra en attraktiv och funktionell design och se till att locket går att producera i Eskilstuna. Om det fanns tid skulle även gångjärnen till de befintliga locken göras mer estetiskt tilltalande och enklare att montera.</p><p> </p><p>En definition av roll-top lock gjordes och den blev: ett rundat lock som fälls eller skjuts undan. En konkurrentanalys visade att inga svenska konkurrenter finns men en hel del utländska. Idesta själva anser att det tyska företaget WMF är största konkurrenten och ett av deras lock detaljstuderades.</p><p> </p><p>En funktionsanalys gjordes och en kravspecifikation ställdes upp. Med detta till hjälp genererades ett antal koncept varav tre valdes ut för vidare utveckling. De tre koncepten ritades upp i CAD och anpassades så de kan tillverkas i Eskilstuna.</p><p> </p><p>Gångjärnen gicks igenom. De nya skulle ha samma funktion som de gamla men ha ett bättre utseende och vara enklare att montera. Intervju med användare visade på ytterligare problem, locket lossnar när det lyfts snett. Idégenerering och val gav en idé att arbeta vidare med.</p><p> </p><p>Av de tre roll-top locken valdes ett ut av Idestas VD som bäst för företaget både utseendemässigt och tillverkningsmässigt. Gångjärnen fick ett bättre utseende men blev svårare och dyrare att tillverka och montera.</p><p> </p><p>Locket går att använda till de bordsvärmare som finns idag men Idesta rekommenderas att göra värmaren större så locket får bättre plats och står stadigare. Gångjärnen rekommenderas att lämnas som de är.</p>
3

Utformning av roll-top lock till bordsvärmare

Eklund, Annelie January 2008 (has links)
Detta examensarbete är avslutningen på civilingenjörsutbildningen på Mälardalens högskola. I arbetet används de kunskaper som förvärvats under utbildningen genom att utveckla en produkt åt företaget Idesta i Eskilstuna.   Uppgiften var att utveckla ett lock av typen roll-top lock till Idestas bordsvärmare. Bordsvärmaren används till att varmhålla mat på bland annat restauranger och locket behövs för att skydda maten från omgivningen och hålla maten fräsch.  Målet var att göra en attraktiv och funktionell design och se till att locket går att producera i Eskilstuna. Om det fanns tid skulle även gångjärnen till de befintliga locken göras mer estetiskt tilltalande och enklare att montera.   En definition av roll-top lock gjordes och den blev: ett rundat lock som fälls eller skjuts undan. En konkurrentanalys visade att inga svenska konkurrenter finns men en hel del utländska. Idesta själva anser att det tyska företaget WMF är största konkurrenten och ett av deras lock detaljstuderades.   En funktionsanalys gjordes och en kravspecifikation ställdes upp. Med detta till hjälp genererades ett antal koncept varav tre valdes ut för vidare utveckling. De tre koncepten ritades upp i CAD och anpassades så de kan tillverkas i Eskilstuna.   Gångjärnen gicks igenom. De nya skulle ha samma funktion som de gamla men ha ett bättre utseende och vara enklare att montera. Intervju med användare visade på ytterligare problem, locket lossnar när det lyfts snett. Idégenerering och val gav en idé att arbeta vidare med.   Av de tre roll-top locken valdes ett ut av Idestas VD som bäst för företaget både utseendemässigt och tillverkningsmässigt. Gångjärnen fick ett bättre utseende men blev svårare och dyrare att tillverka och montera.   Locket går att använda till de bordsvärmare som finns idag men Idesta rekommenderas att göra värmaren större så locket får bättre plats och står stadigare. Gångjärnen rekommenderas att lämnas som de är.
4

ActiveSTB: an efficient wireless resource manager in home networks

Hall, Varrian Durand 15 May 2009 (has links)
The rapid growth of new wireless and mobile devices accessing the internet has led to an increase in the demand for multimedia streaming services. These home-based wireless connections require efficient distribution of shared network resources which is a major concern for the transport of stored video. In our study, a set-top box is the access point between the internet and a home network. Our main goal is to design a set-top box capable of performing network flow control in a home network and capable of quality adaptation of the delivered stream quality to the available bandwidth. To achieve our main goal, estimating the available bandwidth quickly and precisely is the first task in the decision of streaming rates of layered and scalable multimedia services. We present a novel bandwidth estimation method called IdleGap that uses the NAV (Network Allocation Vector) information in the wireless LAN. We will design a new set-top box that will implement IdleGap and perform buffering and quality adaptation to a wireless network based on the IdleGap’s bandwidth estimate. We use a network simulation tool called NS-2 to evaluate IdleGap and our ActiveSTB compared to traditional STBs. We performed several tests simulating network conditions over various ranges of cross traffic with different error rates and observation times. Our simulation results reveal how IdleGap accurately estimates the available bandwidth for all ranges of cross traffic (100Kbps ~ 1Mbps) with a very short observation time (10 seconds). Test results also reveal how our novel ActiveSTB outperforms traditional STBs and provides good QoS to the end-user by reducing latency and excess bandwidth consumption.
5

The study and fabrication of top emission organic light-emitting diodes

Lin, Shin-Ju 27 June 2005 (has links)
The top emission organic light-emitting diodes (TEOLEDs) with multilayer electrodes were studied. Firstly a high reflectivity metal, Al, followed by a high work function metal, such as Pt, Ni or Au, was used as bilyaer anode. It was found that the Al/Au bilayer anode can give rise to a very good luminescent performance if the Al thickness in the bilayer was adjusted to 70 nm. The Al/Au bilayer anode has high reflectivity and good adhesive contact with the hole injection layer. Next the cathode in TEOLEDs composed of multiple layers, LiF/Al/Ag, were studied. The optimum thicknesses in each layer as 0.4/4/15 nm were used to achieve high transparency and good conductivity. The effects of thicknesses of each organic layer were also studied. When the optimum thicknesses of m-MTDATA/NPB/Alq3 were adjusted to 20/40/60 nm, the highest brightness and best luminance efficiency of 8041 cd/m2 and 3 cd/A, respectively, were obtained. The white TEOLED was also studied in this thesis. The ADS082BE was blue host-emitting material and DCJT was orange guest-emitting material. The doped concentration and location were adjusted to control the blue to orange luminance intensity ratio. A white emission with CIE coordinate (0.30, 0.34) was obtained. The highest luminance of 3739 cd/m2 @13.5 Vand best luminance efficiency of 3 cd/A@10V were obtained in the white TEOLED which used multilayer anode and cathode structures. Finally TEOLEDs were also fabricated on the Si wafer and flexible substrate. The brightness and luminance efficiency were (3894 cd/m2;3.8 cd/A on Si wafer),(575 cd/m2, 1.46 cd/A on PES substrate).
6

An OLED Pixel Driver Using Voltage Feedback for Threshold Voltage Shift Compensation

Wen, Cheng-neng 07 July 2008 (has links)
In this thesis we proposed two new pixel circuits for organic light emission display. The first one is 5T1C circuit with two control signals. It can compensate threshold voltage variation and the drop of the power supply voltage that result in OLED current non-uniformity. We have demonstrates that the pixel circuit has high immunity to the threshold voltage variation. In addition, the circuit uses low supply voltage compared with the conventional 5T1C pixel circuit, so it is a low power driver circuit. The second one employs the voltage feedback method and uses the gain value of design circuit for compensating the threshold voltage shift of the driving TFT.To the aim is to reach that to the flow through current of the driving TFT have no relationship with the threshold voltage of TFT. Thus, the OLED can emission light with retaining uniformity light in each time. Because the proposed circuit configuration has low supply voltage and low select pulse voltage, the spike wave phenomenon can be improved and eliminated while the circuit switchs on and off. Due to the circuit supply voltage is decreased, it power consumption reduce significantly and the capacitor charging time is less than 70 £gs. Thus, in this thesis, the two proposed pixel circuits are both of low voltage and low power. The two pixel circuits designed have been fabricated by TSMC 0.35£gm 2P4M CMOS technology with 3.3v power supply. The 5TIC chip area is 1031.8 ¡Ñ 1083.7£gm2 and the measured result shows that when the select pulse is 0~10V, the input voltage is 10V, the select pulse2 is 0~8V and the Vdata¡@voltage range is 0~5V, the OLED current is correspond to 0~20.6£gA and the maximum power consumption is 17£gw. The chip area of the voltage feedback circuit is 1083.38 ¡Ñ 1149.8£gm2 and the measured result shows that when the select pulse is 0~10V, the input voltage is 10V and the feedback resistor is 50£[, the power consumption is 72£gw and the charging time is 51.7£gs.
7

Measurement of m_{top} via Neutrino Weighting in the Dilepton Decay Channels at D0

Temple, Jeffrey W. January 2006 (has links)
A measurement of the top quark mass from dilepton decay channels is presented, using approximately 360 pb-1 of data colleced by the D0 experiment at Fermilab. The mass is measured from a total of 21 candidate dilepton events, using the neutrino weighting scheme. The measured mass is found to be 175.6+/-10.7(stat.)+/-6.0(syst.) GeV. This result is in good agreement with the current world average of the top quark mass.
8

Impacts of a top-predator emergence in an exploited ecosystem : North Sea hake and saithe. : Which interactions ? What consequences ? / Impacts de l’émergence d’un top-prédateur dans un écosystème exploité : le merlu et le lieu noir de mer du Nord. : Quelles interactions ? Quelles conséquences ?

Cormon, Xochitl 11 December 2015 (has links)
La population de lieu noir (Pollachius virens) de mer du Nord a une importance économique élevée pour les pêcheries européennes. Depuis une dizaine d’années, l’abondance du lieu noir a décliné, alors que le merlu (Merluccius merluccius), qui était peu pêché dans cette zone, a vu son abondance fortement augmenter. Ce travail se concentre sur la nature des interactions écologiques entre le lieu noir et le merlu en Mer du Nord afin de déterminer si la récente émergence du merlu dans cette zone pourrait expliquer, au moins en partie, le récent déclin du stock de lieu noir. Les résultats obtenus lors de ce travail de recherche ont permis de valider l’hypothèse de compétition entre le lieu noir et le merlu. De plus, cette étude a révélé un impact potentiellement négatif de l’augmentation du merlu sur la biomasse de lieu noir. L’émergence du merlu en mer du Nord doit donc être sérieusement prise en compte dans les avis scientifiques supportant les décisions de gestion encadrant la pêche du lieu noir, mais aussi des autres espèces de mer du Nord que l’émergence du merlu est susceptible d’affecter. Finalement, ce travail fournit donc les premières bases écologiques nécessaires à une investigation plus détaillée des conséquences de l’émergence du merlu dans un écosystème hautement exploité tel que la mer du Nord. / North Sea saithe (Pollachius virens) has high economic value for European fisheries. In recent years, North Sea saithe abundance has decreased, while abundance of hake (Merluccius merluccius), which was rarely fished in the North Sea, has increased dramatically in the area. This work investigate the nature of the ecological interactions between saithe and hake in the North Sea, in order to understand if recent hake emergence in this area could explain, at least partially, the recent decline of the saithe stock. The results obtained during this research suggested competitive interactions between saithe and hake predators in the area. In addition, this investigation revealed potential negative effects of hake emergence in the North Sea on the resident saithe stock. Therefore, hake emergence in the North Sea must be taken into account when managing commercial species fisheries, the sustainability of which may be threatened by this up-coming predator. Finally, the results obtained within this PhD research thesis highlight the importance of hake as an up-coming predator and competitor in the North Sea, and provide the necessary basis for further investigations of hake potential ecological and economic function in this exploited ecosystem.
9

Worst case driver pro Top stromy / Worst case driver for Top trees

Ondráček, Lukáš January 2018 (has links)
A top tree data structure solves one of the most general variants of a well- studied dynamic trees problem consisting in maintenance of a tree along with some aggregated information on paths or in individual trees, possibly in a mutable way, under operations of inserting and removing edges. It provides a simple interface separated from both an internal top tree structure representing a hierarchical partitioning of the graph, and a driver ensuring its depth to be logarithmic, which has a crucial role for the efficiency of the data structure. The driver proposed in this thesis is based on biased trees, combining techniques used in the worst-case version of link/cut trees and in the amortized driver for top trees: An input forest is decomposed into heavy paths and interleaving vertices, all of them being represented by biased trees connected together to form exactly the top tree structure. The driver is meant to be a more efficient alternative to the originally proposed one, and a comparably efficient alternative to the driver proposed by Werneck; there is a room for their experimental comparison.
10

Fabrication top-down, caractérisation et applications de nanofils silicium / Top-down fabrication, characterisation and applications of silicon nanowires

Vaurette, François 22 January 2008 (has links)
Cette thèse porte sur l'étude de nanofils silicium réalisés par approche top-down. Elle s'inscrit dans le contexte de la miniaturisation des composants et la compréhension du transport dans les systèmes 1D. Deux voies de fabrication sont envisagées: la lithographie par AFM (Microscope à Force Atomique) et la lithographie électronique. Cette dernière étant plus reproductible, les dispositifs finaux sont fabriqués par cette technique, à partir d'un substrat SOI et plusieurs étapes de gravure et métallisation. L'étude des nanofils par mesures l(V) nous permet de mettre en évidence une zone déplétée à l'interface Si/SiO2 natif. Grâce à l'utilisation de nanofils de largeurs et de longueurs différentes, nous sommes capables de déterminer la largeur de la zone déplétée, la densité d'états d'interface ainsi que le niveau de dopage des nanofils. L'évolution de la résistance des nanofils avec la température est également étudiée et montre une dépendance associée à la diffusion des phonons de surface. Trois applications sont ensuite décrites : un décodeur, un commutateur de courant et un capteur biologique. En effet, la gravure locale des nanofils conduit à une modulation de la bande de conduction, rendant possible la réalisation d'un décodeur. D'autre part, la fabrication de croix à base de nanofils et de grilles latérales à proximité des croix qui contrôlent le passage du courant dans les différentes branches permet de former un commutateur de courant. Enfin, grâce au rapport important de la surface par rapport au volume des nanofils et leur bonne fonctionnalisation chimiques, ceux-ci sont utilisés pour détecter électriquement des interactions biologiques (détection de l'ovalbumine). / This work focuses on the study of silicon nanowires made by a top-down approach. The context of the study is the miniaturisation of the components and the understanding of the transport in 1D systems. Two fabrication approaches are studied : AFM lithography (Atomic Force Microscope) and e-beam lithography. The latter being more reproducible, the final devices are fabricated by this technique using a SOI substrate and multiple steps of etching and metallization.Transport characterization of the Si nanowires allows us to highlight a depleted area at the interface Si/native SiO2. Using nanowires with different widths and lengths, we can determine the depletion width, the surface state density as well as the doping level of the nanowires. The evolution of the nanowires resistance with temperature is also investigated, showing a dependence associated with surface phonons scattering. In the last chapter, three applications are described : a decoder, a current switch and a biosensor. The use of a local etching allows the modulation of the conduction band of the nanowires, opening the way to build a decoder using two local gates. Crossbar structures, where lateral gates which can derive the current in the di_erent branches, lead to the fabrication of a current switch. Finally, thanks to the large surface to volume ratio in these structures, the nanowires are used to detect electrically the interactions between molecules (ovalbumine detection).

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