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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.
191

Circuit breaker transient recovery voltage analysis with shunt capacitor bank configurations

Guha, Anirudh 21 February 2011 (has links)
Transient Recovery Voltage (TRV) is an important consideration in the selection and installation of circuit breakers with appropriate ratings. Capacitor banks with inrush current limiting reactors are an integral part of the power system. Capacitor banks with inrush reactors on the load side terminal of the capacitor breaker alter the TRV seen across the breaker and it is critical to carry out the TRV analysis to prevent circuit breaker failure. TRV analysis has been performed for various capacitor bank - inrush reactor configurations, with the fault occurring at different terminals on the load side. Analytical solutions have been presented for both single-phase and three-phase ungrounded capacitor banks. Neutral displacement voltage of three-phase ungrounded capacitor banks result in increased stress across the breaker. Results have been validated with PSCAD simulation and MATLAB plots. / text
192

STRESS AND EPISODIC MEMORY: THE FATE OF NEUTRAL VERSUS EMOTIONAL INFORMATION

Payne, Jessica Danielle January 2005 (has links)
This paper describes two experiments, each of which investigated the impact of stress on human episodic memory. All participants watched narrated slide shows containing emotional and neutral information. Experiment 1 demonstrated that pre-learning exposure to a psychological stressor (the Trier Social Stress Test or "TSST"; Kirschbaum, Pirke & Hellhammer, 1993) preserved or enhanced memory for emotional aspects of the slide show, but impaired memory for neutral aspects of the slide show. Moreover, stress exposure disrupted memory for information that was visually and thematically central to the slide show. Memory for peripheral information, on the other hand, was unaffected by stress. Experiment 2 replicated these results and extended them to a similar paradigm, where participants viewed separate emotional and neutral slide shows, and saliva was tested for the stress hormones cortisol and norepinephrine. Similar to the results of Experiment 1, stress disrupted memory for the neutral slide show, but enhanced memory for the emotional slide show. Salivary cortisol levels at retrieval were negatively correlated with memory for the neutral slide show. These results are consistent with theories invoking differential effects of stress on brain systems responsible for encoding and retrieving emotional memories (the amygdala) and non-emotional memories (e.g. the hippocampal formation, frontal cortex), and inconsistent with the view that memories formed under high levels of stress are qualitatively the same as those formed under ordinary emotional circumstances. These data, which are also consistent with results obtained in a number of studies using animals and humans, have implications for the traumatic memory debate and theories regarding human memory.
193

Quantum Information Science with Neutral Atoms

Rakreungdet, Worawarong January 2008 (has links)
We study a system of neutral atoms trapped in a three-dimensional optical lattice suitable for the encoding, initialization and manipulation of atomic qubits. The qubits are manipulated by applied electromagnetic fields interacting with dipole moments of the atoms via light shifts, Raman transitions, Zeeman shifts, and microwave transitions. Our lattice is formed by three orthogonal one-dimensional lattices, which have different frequencies so that interference terms average to zero. This geometry allows considerable freedom in designing the component one-dimensional lattices, so that they provide not only confinement but also independent control in each dimension. Our atomic qubits are initialized from a laser-cooled atomic sample by Raman sideband cooling in individual lattice potential wells. We have demonstrated accurate and robust one-qubit manipulation using resonant microwave fields. In practice such control operations are always subject to errors, in our case spatial inhomogeneities in the microwave Rabi frequency and the light shifted qubit transition frequency. Observation of qubit dynamics in near real time allows us to minimize these inhomogeneities, and therefore optimize qubit logic gates. For qubits in the lattice, we infer a fidelity of 0.990(3) for a single pi-pulse. We have also explored the use of NMR-type pulse techniques in order to further reduce the effect of errors and thus improve gate robustness in the atom/lattice system. Our schemes for two-qubit quantum logic operations are based on controlled collisional interactions. We have experimented with two schemes in order to probe these collisions. The first involves manipulation of the center-of-mass wavepackets of two qubits in a geometry corresponding to two partially overlapping Mach-Zender interferometers. Unfortunately, this scheme has proven extremely sensitive to phase errors, as the wavepackets are moved by the optical lattice. The other scheme starts with two qubits in spatially separated traps, and utilizes microwaves to drive one or both qubits into a third trap in-between the two qubits. Once the wavepackets overlap, the collisions create a large energy shift which can be probed spectroscopically.
194

Sibling Interaction in Preschool Children

Duchastel, Christina January 2005 (has links)
This study investigates interaction in eight sibling pairs aged 1-5 years with the purpose of examining the prevalence of certain variables constituting the interaction. The siblings were observed with video camera while playing with a toy brought along by the author. In order to validate and expand upon the information obtained from the observations, the parent(s) were asked to respond to a number of questions from a Questionnaire. The variables investigated were reciprocal and complementary interaction, asymmetrical roles, imitation, conflict, joint and parallel play and communication. The results obtained indicate that, in these eight sibling pairs, reciprocal interaction, that is interaction taking place on an equal level, is signified by joint play. Complementary interaction, that is interaction taking place on different levels, is signified by parallel play. High activity level for boys versus low activity level for girls in three sibling pairs were observed to correspond to gender-specific play activities in everyday life.
195

Fler än tusen ord : En bildanalys av regeringsalternativen och dess partiföreträdare i Göteborgs-Posten & Hallandsposten en månad före riksdagsvalet 2010

Lundell, Jonathan January 2012 (has links)
Uppsatsen studerar de fotografiska bilder föreställande Alliansen och de Rödgröna, samt dess enskilda partiledare, som från 2010-08-19 till 2010-09-19 publicerades i Göteborgs-Posten samt Hallandsposten. Syftet är att klassificera varje enskild bild som gynnande, missgynnande eller neutral. Teorin utgår ifrån klassisk kommunikationsteori. Vidare diskuteras bildens betydelse, verklighetsgestaltning samt medias demokratiska uppdrag, semiotik, retorik och ansiktsuttryck. Metoden är en kvantitativ och kvalitativ innehållsanalys. Materialet är tidningarnas pappersupplagor. För att analysera bilden används ett tolkningsschema med grund i teorin om bilden och bildens kontext. Resultatet visar en jämlik fördelning av antalet bilder på regeringsalternativen, dock fler på Alliansen i Hallandsposten. Fördelningen av antalet bilder på partiledarna följde i stort partiernas storlek. Resultatet visar att Alliansen och dess partiledare hade fler gynnande bilder, dock med viss avvikelse i Hallandsposten. Anmärkningsvärt: Hallandsposten noterade inga helsidor eller framsidor där partiledare/regeringsalternativ figurerade, till skillnad på Göteborgs-Posten som noterades för flertalet.
196

The Effects of a Neutral Cannabinoid-1 Receptor Antagonist on Intravenous Nicotine Self Administration Behaviour

Pryslawsky, Yaroslaw 19 March 2014 (has links)
Introduction: Tobacco dependence is a chronic disorder that carries the risk of relapse at any time point during abstinence. It is a major health issue in the world and current pharmacotherapies have had limited efficacy. Therefore, development and validation of novel treatments are required. Objective: Investigate the novel neutral cannabinoid-1 receptor antagonist AM4113 on nicotine (main psychoactive ingredient in tobacco)-taking behaviour in animals. Methods: Using the nicotine intravenous- and food control- self administration paradigms, we tested the acute and chronic (10-days) effects of AM4113 on nicotine- and food-taking behaviour. Results: Acute AM4113 treatments (1-, 3-, 10-mg/kg) reduced nicotine self administration. Chronic AM4113 administration (10mg/kg) produced a sustained reduction of nicotine-taking behaviour during the course of the treatment. In the similar food control self administration experiments, AM4113 overall produced no effect. Conclusion: AM4113 can attenuate nicotine-taking behaviour and its effect is sustained under chronic treatment.
197

The Effects of a Neutral Cannabinoid-1 Receptor Antagonist on Intravenous Nicotine Self Administration Behaviour

Pryslawsky, Yaroslaw 19 March 2014 (has links)
Introduction: Tobacco dependence is a chronic disorder that carries the risk of relapse at any time point during abstinence. It is a major health issue in the world and current pharmacotherapies have had limited efficacy. Therefore, development and validation of novel treatments are required. Objective: Investigate the novel neutral cannabinoid-1 receptor antagonist AM4113 on nicotine (main psychoactive ingredient in tobacco)-taking behaviour in animals. Methods: Using the nicotine intravenous- and food control- self administration paradigms, we tested the acute and chronic (10-days) effects of AM4113 on nicotine- and food-taking behaviour. Results: Acute AM4113 treatments (1-, 3-, 10-mg/kg) reduced nicotine self administration. Chronic AM4113 administration (10mg/kg) produced a sustained reduction of nicotine-taking behaviour during the course of the treatment. In the similar food control self administration experiments, AM4113 overall produced no effect. Conclusion: AM4113 can attenuate nicotine-taking behaviour and its effect is sustained under chronic treatment.
198

Creation of entangled states of a set of atoms in an optical cavity

Haas, Florian 13 February 2014 (has links) (PDF)
In this thesis, we demonstrate the creation and characterization of multiparticle entangled states of neutral atoms with the help of a high finesse cavity. Our experimental setup consists of a fibre-based high finesse cavity above the surface of an atom chip. It allows us to prepare an ensemble of 87Rb atoms with well-defined atom number. The atoms are trapped in a single antinode of an intracavity standing wave dipole trap and are therefore all equally coupled to the cavity mode. We present a scheme based on a collective, quantum non-destructive (QND) measurement and conditional evolution to create symmetric entangled states and to analyze them at the single-particle level by directly measuring their Husimi Q function. We use this method to create and characterize W states of up to 41 atoms. From the tomography curve of the Q function, we reconstruct the symmetric part of the density matrix via different reconstruction techniques and obtain a fidelity of 0.42. Furthermore, we have devised an entanglement criterion which only relies on comparing two populations of the density matrix. We use it to infer the degree of multiparticle entanglement in our experimentally created states and find that the state with highest fidelity contains at least 13 entangled particles. In addition, we show preliminary results on experiments to count the atom number inside a cavity in the QND regime and to create entangled states via quantum Zeno dynamics.
199

Aktyvuotų tirpalų, pagamintų įrenginyje STEL, panaudojimo melžimo įrengimų ir patalpų dezinfekcijai tyrimas / The investigation of the application of active solutions, produced in STEL type equipment, in washing and disinfecting milking mashines and parlours

Libnickienė, Indrė 12 April 2005 (has links)
At the time there are various options in the range of disinfecting materials applied in animal husbandry. In animal husbandry and food processing industry a new type of biocide – neutral anolyte (ANK) has been used for the purposes of disinfection, presterilization, purification and sterilization. ANK is produced in the STEL devices by electrochemical activation of sodium chloride solution. Aim of the study: to evaluate (under the laboratory conditions) the antibacterial washing qualities of neutral anolyte ANK, produced in the STEL-10N-120-01 devices, in its application for washing and disinfecting milking equipment and parlours. The efficiency of disinfection was estimated applying the method of pads (LAST EN ISO 4833: 2003). Inhabitable materials in the water were identified using “Delves” test, according to the standard LST 1263:1999. The physical-chemical examinations of water were carried (HN 24:2003). Under the laboratory conditions, anolyte ANK (produced in the STEL-10N-120-01 devices) solution with the concentration of 0.05% suppressed the increase of the Escherichia coli, Staphylococcus aureus, Streptococcus agalactiae, Salmonella and the coliform bacteria. The anolyte ANK solutions with the concentration 0.05% and 0.025% (made from the 0.05% solution watering it down in proportion 1:1) were not efficient in the pig farm A. The 0.05% anolyte ANK solution was efficient sanitarily treating the milkers equipment in the farming B.
200

The effect of heat on fruit size of day-neutral strawberries

Chen, Dianlong 25 April 2013 (has links)
The effect of temperature on fruit and achene characteristics of day-neutral strawberries were tested by two field experiments in Florida and Ontario, and one controlled-environment experiment. The results suggested that fruit became smaller as weather became hotter. This was mainly caused by ovule number and fruit volume/ovule which were determined before flowering. Fruit volume was determined by cell number and cell size. The cell number was determined before flowering, and after flowering there are a constant number of cell divisions. Cell volume plays a relatively minor role on fruit volume and cool temperature increased cell volume. Ovule number was determined 462 degree days before flowering and 14°C appeared to be the optimum temperature for ovule initiation. When there was a smaller proportion of developed achenes, the achenes appeared to be larger and have a similar contribution to fruit development than when there was a larger proportion. ‘Albion’ performed better in Florida, whereas ‘San Andreas’ performed better in Ontario.

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