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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.
121

Study of Particulate Number Concentrations in Buses running with Bio diesel and Ultra Low Sulfur diesel

Somuri, Dinesh Chandra 09 June 2011 (has links)
No description available.
122

Aerosol particles generated by diesel-powered school buses at urban schools

Hochstetler, Heather Ann 19 October 2010 (has links)
No description available.
123

Uncertainty Analysis of Resistive Soot Sensors for On-BoardDiagnostics of Automotive Particulate Filters

Baradwaj, Nithin V. January 2013 (has links)
No description available.
124

An analysis of NOx and PM emissions in idling and moving conditions of buses with EGR and Non-EGR engines running on biodiesel

Yarlagadda, Manideep January 2016 (has links)
No description available.
125

Evaluating ambient fine particulate matter source regions in the Ohio River Valley Region

Li, Sujuan 04 December 2003 (has links)
No description available.
126

Electrostatic Precipitation Technologies for the Mitigation of Particulate Matter Emissions from Poultry Facilities

MANUZON, RODERICK BEROIN 31 August 2012 (has links)
No description available.
127

Diode Predistortion Linearization for Power Amplifier RFICs in Digital Radios

Haskins, Christopher Burke 26 April 2000 (has links)
The recent trend in modern information technology has been towards the increased use of portable and handheld devices such as cellular telephones, personal digital assistants (PDAs), and wireless networks. This trend presents the need for compact and power efficient radio systems. Typically, the most power inefficient device in a radio system is the power amplifier (PA). PA inefficiency requires increased battery reserves to supply the necessary DC bias current, resulting in larger devices. Alternatively, the length of time between battery charges is reduced for a given battery size, reducing mobility. In addition, communications channels are becoming increasingly crowded, which presents the need for improved bandwidth efficiency. In order to make more efficient use of the frequency spectrum allocated for a particular system, there is a push towards complex higher order digital modulation schemes in modern radio systems, resulting in stricter linearity requirements on the system. Since power efficient amplifiers are typically nonlinear, this poses a major problem in realizing a bandwidth and power efficient radio system. However, by employing various linearization techniques, the linearity of a high efficiency PA may be improved. The work presented in this thesis focuses on diode predistortion linearization, particularly for PA RFICs in digital radios. Background discussion on common linearization techniques available to the PA designer is presented. In addition, a discussion of traditional and modern methods of nonlinearity characterization is presented, illustrating the nonlinear PA effects on a modulated signal. This includes the use of two-tone analysis and the more modern envelope analysis. The operation of diode predistortion linearizers is discussed in detail, along with diode optimization procedures for PA linearization with minimum impact on return loss and gain. This diode optimization is effective in improving the ability to integrate the predistorter into a single, linearized PA RFIC chip. MESFET and HBT based diode linearizers are studied for use with corresponding MESFET and HBT based PAs in the 2.68 GHz and 1.95 GHz frequency bands, respectively. Results show an improvement in adjacent channel power ratio (ACPR) due to the linearizer in both MESFET and HBT cases. A fully integrated 1.95 GHz linearizer and PA RFIC in HBT technology is also presented. Design considerations, simulations, and layouts for this design are presented. Finally, several recommendations are made for continued research in this area. / Master of Science
128

Automatisering av magnetiseringav rotor i elmotor : Analyser av tekniska utmaningar och lösningar för robotiserad magnetisering

Engström, Erik January 2024 (has links)
This thesis aims to develop an automated process for the magnetization of a rotor for an electricmotor used in an electric car, using an industrial robot. The purpose is to outline how such a solutioncould be designed and to detail the steps taken to develop a design for the complete process. Apreliminary study was conducted to identify existing challenges and propose solutions. To gathermore information about the design process, experiments were carried out to determine the forcesneeded to place the magnets into the rotor, and the results were used in the subsequent design.The conclusion is that a theoretical solution is possible, and a robot tool has been designed in CAD.However, further studies are needed to validate a fully functional process for the magnetization ofthe studied rotor. / Detta arbete undersöker möjligheten att automatisera ett för närvarande manuellt moment i monteringen av en elmotor till en elbil med hjälp av en robot. Fokus ligger på utformningen av en sådan lösning och de utmaningar som behöver hanteras. Det moment som ska automatiseras är monteringen av magneter inuti den roterande delen av elmotorn, även kallad rotorn. Detta kräver en hög precision då det är små marginaler och magneterna är väldigt starka. Den största utmaningen är således att åstadkomma samma precision som en människa kan uppnå, fast med en robot. Människor kan enkelt göra små korrigeringar utan att tänka på det, med en robot behöver betydligt mer information och programmering för att utföra liknande uppgifter. Under arbetets gång har en design tagits fram där en robot, med hjälp av ett speciellt verktyg, kan föra in magneter i rotorn innan den monteras in i själva elmotorn. Genom att använda en robot för detta moment kan risker elimineras som annars uppstår när människor hanterar kraftfulla magneter för hand. Detta skulle inte bara förebygga skador för manuell personal, utan också skapa ett snabbare och effektivare monteringsmoment. Under arbetet har olika tekniska lösningar som finns idag undersökts som kan göra en robot lämplig för uppgiften. Det finns dock fortfarande utmaningar som behöver undersökas vidare innan en färdig lösning kan realiseras praktiskt. Sammanfattningsvis har en principiell design för en automationslösning tagits fram. Det krävs dock ytterligare forskning och utveckling för att kunna skapa en prototyp och implementera lösningen praktiskt.
129

The Influence of Psychological Momentum on Basketball Shooting Performance

Harris, Connor 05 1900 (has links)
The purpose of this research was to examine the influence of fictitious scoring updates on psychological momentum (PM) and athletic performance in a competitive basketball setting. The participants included in this study were 50 male undergraduate students who reported having played basketball previously and qualified by being able to make more than 24% (12 out of 50) of their 3-point shots in a pre-trial session. Participants were told that they were competing in a 50 shot, 3-point shooting competition against another individual, equal in ability. After every 10 shots, participants were given a fabricated score update and answered four questions used to measure PM. Results showed that the fictitious score updates significantly (p < .01) influenced participants’ PM scores, where those who were told they led had higher PM scores than those who were told they trailed. As for shooting performance, no significant differences (p = .76) were found between positive and negative PM states for participants who reported experiencing both during the competition. Together, these findings suggest that manufactured score updates can influence PM, but resultant performance differences may not exist. Results of this study lend support to the notion that PM is experienced by athletes. However, when examining basketball shooting performance, the momentum-performance relationship is statistically unsupported. Thus, although PM is thought of by many as a game-changing factor, this study would suggest that PM plays a negligible role in changes to individual performance.
130

Synthèses de nouvelles monocouches auto-assemblées à partir d’organosilanes fonctionnels capables d’auto-association par liaisons hydrogène / Synthesis of new self-assembled monolayers with functional organosilanes capable of auto-association by H-bonds

Ramin, Michael 15 December 2010 (has links)
Il existe une très forte demande en biocapteurs pour la détection d’agents pathogènes dans le domaine environnemental et médical. Dans ce contexte, le contrôle de l’état de surface des biocapteurs joue un rôle crucial. Les monocouches auto-assemblées (Self-Assembled Monolayers, SAMs) permettent de fonctionnaliser de manière homogène et reproductible ces surfaces. Ces SAMs sont généralement obtenues à partir d’agents de couplage siliciés à longue chaîne alkyle. Mais, ces composés sont souvent difficiles à synthétiser et à purifier en raison de leurs faibles solubilités dans les solvants organiques. C’est pour cela que nous avons proposé d’introduire une fonction polaire (amide ou urée) au sein de ces films. Ces fonctions permettent également un auto-assemblage des molécules sur le substrat au moyen de liaisons hydrogène entre les molécules. Les nouvelles monocouches fonctionnelles ont été caractérisées entre autres par spectroscopie infrarouge de réflexion-absorption par modulation de polarisation (PM-IRRAS) ce qui a permis d’identifier les différents groupes moléculaires. Ces monocouches ont aussi montré leurs capacités à immobiliser une molécule biologique (Protéine A). / There is an increasing demand for biosensors to detect pathogens in environmental and medical fields. In this context, the control of the surface properties plays an important role. Self-Assembled Monolayers (SAMs) allow to functionalize these surfaces homogeneously and reproducible. SAMs on silicon based surfaces are usually obtained from silylated coupling agents with long alkyl chain. However, these compounds are often difficult to purify owing to their low solubility in organic solvents. That’s why we proposed to introduce a polar function (amide or urea) in the molecular structure. These precursors were also capable of association by H-bonds and offer possibilities to control the organic assembly on the surfaces. The new functional monolayers were characterized by Polarization Modulation Infrared Reflection Adsorption Spectroscopy (PM-IRRAS) and others techniques such as XPS and contact angle in order to identify the different molecular groups on the surface. These functionalized monolayers have also shown their ability to immobilize biomolecules (Protein A).

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