I present a comprehensive investigation of fast stars in the Milky Way, from brisk disc stars to stars escaping the Galaxy. My thesis is that fast stars are the smoking guns of extreme stellar collisions and explosions, and so can act as an intermediary to studying these theoretically-unconquered astrophysical processes. In Chapter 1 I give a history of fast stars, address what it means for a star to be fast, and describe the processes that accelerate stars. I concisely summarise the Gaia mission, whose recent data releases heavily influenced this thesis. Supernovae in binary systems can fling away the companion; if a runaway companion can be associated with a supernova remnant, then together they reveal the evolution that led to the supernova. However, these associations are difficult to establish. In Ch. 2, I develop a sophisticated Bayesian methodology to search the nearest ten remnants for a companion, by combining data from Gaia DR1 with a 3D dust-map and binary population synthesis. With Gaia DR2, I will identify companions of tens of supernova remnants and thus open a new window to studying late-stage stellar evolution. It is unknown why 17% of B stars are spinning near break-up; these stars are termed Be stars because of emission lines from their ejected material. Their rapid spin could be due to mass transfer, but in Ch. 3 I show this would create runaway Be stars. I demonstrate using a hierarchical Bayesian model that these exist in sufficient numbers, and thus that all Be stars may arise from mass transfer. The stars escaping the Milky Way are termed hypervelocity stars. In Ch. 4, I overturn the consensus that the hypervelocity stars originated in the Galactic centre by showing that a Large Magellanic Cloud (LMC) origin better explains their distribution on the sky. In Ch. 5 I present three ground-breaking hypervelocity results with Gaia DR2: 1) only 41 of the 524 hypervelocity star candidates are truly escaping, 2) at least one of the hypervelocity stars originates in the LMC, and 3) the discovery of three hypervelocity white dwarf runaways from thermonuclear supernovae.

Understanding the asymmetry in core collapse supernova explosions is pointed out by various astrophysicists as it is the key factor in determining the observational properties of the pulsars. The initial kick given by the ex- plosion to the pulsar affects its spin period and space velocity. Up to now, although the observations do not show a direct relation between the observational features of the pulsar and its space velocity, they show a clear relation between the spin period and the magnetic field strength, hence its radiation processes. In this thesis, as the method, tracing the companions of progenitors if they were in close binaries, which becomes a runaway star after the supernova explosion was chosen. Over the candidates selected in Guseinov et al (2005), the spectral types of 11 runaway candidates from 7 supernova remnants determined through analyzing their spectroscopic observations. Radial velocity determination was applied to the discovered B6V type star GSC 03156-01430 inside the supernova remnant G78.2+2.1. Also by studying the proper motion data, we compared the motion of the runaway star and the related pulsar in order to determine the asymmetry in the supernova explosion. The neutron star PSR 2021+4026 is moving with a 2-D velocity of &sim / 580 km/s with respect to the rest frame of its birth association Cyg OB9. &sim / 550 km/s more than expected in the symmetric case. Re-constructing the pre-supernova binary shows that the asymmetry in the supernova explosion does not depend on the binarity.

This thesis project solve problematic of thermal proces in lead-acid batteries. There are decribed history of lead – acid batteries, distributions of batteries, overview of construction lead – acid batteries and VRLA batteries and is decribed thermal runaway proces and basic termal process. They are listed here practical results and the measurements is concluded.

Because of the relative uniqueness of the runaway experience as it now exists, minimal current research information is available. It was our feeling that knowledge about runaways, their families, and the social agencies which serve them is essential if significant prevention and treatment for the problem were to be implemented by the community. The purpose and scope of this exploratory research was essentially two-fold; to contribute descriptive information about runaway youth and their families to the community, and to evaluate the current populations of two agencies which service them. An underlying goal throughout the research was to utilize the data collected to identify trends in runaway behavior, increase the potential for predictability, and provide some real insight into prevention techniques. Our informal hypothesis was that there is a significant difference in specific variables between runaway and non-runaway populations. We were interested in developing a typology of runaways, identifying those factors which increase a child's probability that he/she will run away. Finally, we wanted to know if different agencies tend to serve a particular kind of runaway who has specific characteristics. These constituted the major goals for this research practicum. Since most law enforcement and social service energy is spent at the point of crisis, this research sought to identify trends in the scope of the problem which would aid preventative services for runaways. Hopefully, the impact of this practicum will influence crucial issues in terms of family dynamics, treatment intervention, community resources, and delinquency prevention. The results of this study will be distributed to the participating agencies and other interested segments of the community. Probably more detailed hypothesis testing will be needed; however, this study forms a base of information for future research. Better assessment of meeting the problem by evaluating all existing services should be a continuing focus for the social service community.

The purposes of this study were: (1) to examine a select sample of both runaways and nonrunaways at six Oregon residential treatment facilities; (2) to determine the amount and type of preplacement visitation and counseling done within these agencies; (3) to determine the effect preplacement visitation and counseling has upon the studied sample of runaways and nonrunaways in decreasing or controlling the number of runs from the agencies involved; and (4) to determine significant characteristics between runaway and nonrunaway populations. Testing materials included a two-part questionnaire, part of which was developed with girls from one of the participating agencies. Running, which today is looked upon as a status offense, is costly in the effect it has upon the mind and emotions of the young runners, as well as the effect it has upon the budgets of the agencies involved. Running from a residential treatment program is also disruptive to the treatment plan which has been set up for that particular youth. The work which has been done to date in this area is sketchy and incomplete. It does not clearly tell us whether or not preplacement counseling actually reduces the desire to run and helps to create a more comfortable atmosphere for the teen-ager. Our sample consisted of both runners and a random sample of nonrunners from the participating agencies for the month of October.

<p> Energy storage has received much attention due to the increasing use of energy, especially renewable energy. Lithium-ion batteries have great characteristics for electrical energy storage. Higher specific energy density, cycle life, cell voltage, shorter charge times gives lithium-ion batteries favorable energy storage characteristics over other battery chemistries. Although lithium-ion batteries are increasing in use for electrical energy storage, their safety still poses an engineering problem. When lithium-ion batteries are abused, they can enter thermal runaway. This event is dangerous as it can eject hot gases and shrapnel. Previous studies focused on different aspects of thermal runaway, for example, heat generation from chemical reactions, propagation to other cells, and the physics of gas venting. One phenomenon that has not received much attention is the evaporation of the electrolyte out of a failed lithium-ion battery. Understanding the effect of electrolyte evaporation is key to having a more complete understanding of thermal runaway. In this thesis, the physics of electrolyte evaporation is studied with the purpose of developing more accurate thermal abuse models. An evaporation model was developed, based on porous drying theory and a 1-D liquid diffusion process. Experiments were conducted to identify the liquid diffusion coefficient which governs the rate of electrolyte transport within the porous separator within the battery. The 1-D liquid diffusion model was then implemented into an existing thermal abuse model and exercised for a typical oven test scenario. Results showed that the physics-based evaporation model resulted in excellent agreement with experimental data at different oven temperatures.</p>

Material degradation and a decrease of fuel quality are common phenomena when storing biomass. A magnitude of 7.8% has been reported to degrade over five months when storing spruce wood chips in the winter in Central Europe. This thesis presents a theoretical study of biomass storage. It includes investigations of bio-chemical, chemical and physical processes that occur during storage of chipped woody biomass. These processes lead to degradation caused by micro-activity, chemical oxidation reactions and physical transformation of water. Micro-activity was modeled with Monod kinetics which are Michaelis-Menten type of expressions. The rate expressions were complemented with dependency functions describing the impact of oxygen, moisture and temperature. The woody biomass was divided into three fractions. These fractions represent how hard different components of the wood are to degrade by microorganisms. Chemical oxidation was modeled as a first order rate expression with respect to the active components of the wood. Two different cases have been simulated during the project. Firstly, an isolated system with an initial oxygen concentration of air was considered. This case displayed a temperature increase of approximately 2˚C and a material degradation less than 1%. The second case considered an isolated system with an endless depot of oxygen. This case resulted in degradation losses around 0.45-0.95% in the temperature range between 65-80˚C during approximately 300 days of storage. The temperature increased slowly due to chemical oxidation.

Personality patterns of sexually abused female adolescent runaways are compared to personality patterns of physically abused female adolescent runaways. Eighty-six female adolescents from 13 to 17 years of age completed a self report inventory to determine personality traits. To test the hypotheses of the study, a multivariate analysis of variance was conducted, followed with univariate tests to find differences on separate dependent measures. Results indicated that on the Jesness Inventory there may be a common personality pattern associated with abuse. Univariate tests yielded data which indicated that although there may be a general personality pattern for abused adolescents, there were significant differences between the physically and sexually abused adolescents on some personality variables. Results were evaluated taking into account the selective sample from which the population was drawn. Recommendations for future research included the use of projectives, a more comprehensive personality inventory, and selected demographics.

L’objectif de ce mémoire est de rendre compte d’une figure particulièrement dynamique dans l’écriture de Leïla Sebbar, celle de l’adolescent fugueur. Mohamed dans Le Chinois vert d’Afrique (1982) et Shérazade dans Shérazade, 17 ans, brune, frisée, les yeux verts (1984), personnifient une réalité autre que celle accolée aux jeunes descendants de l’immigration maghrébine (surtout algérienne), partagés entre les codes culturels du pays d’origine et ceux du pays de naissance. L’hybridité des personnages et leur mobilité aléatoire permettent de réévaluer les discours sociaux dominants émis en France, pays tiraillé entre les aspirations d’unité nationale et l’histoire coloniale. Le premier chapitre fera état du contact des fugueurs avec la représentation picturale et sa place dans la constitution de leur identité. À la lumière de ces observations, la seconde partie du travail se penchera sur la prise de conscience du regard de l’Autre et le questionnement de l’image préconçue de l’adolescent de banlieue inculte en mal d’insertion sociale. La déconstruction de ce cliché permettra dans le troisième chapitre d’aborder la réappropriation de l’objet culturel par les fugueurs, procédant à une véritable démocratisation de la culture élitiste. Le quatrième chapitre sera enfin consacré au mouvement des fugueurs dans l’espace et dans le temps. Nous y verrons comment les fugueurs, intermédiaires entre la ville et sa banlieue mais aussi entre le paradis perdu du pays d’origine et le désarroi des parents immigrés, provoquent la relecture de l’histoire des générations passées tout en gardant un œil critique sur l’avenir. / The purpose of this master’s thesis is to study the dynamic figure of the runaway in the writing of Leïla Sebbar. Mohamed in “Le Chinois Vert d’Afrique” (1982) and Shérazade in “Shérazade, 17 ans, brune, frisée, les yeux verts” (1984), personifie a reality that the young descendants of the North African immigration must encounter, torn between the cultural codes of the country of origin and the country of birth. The blend of the characters’ culture and their constant mobility reassess the dominant social discourse during a time when France was torn between the aspirations of a national unity and colonial history. The first chapter examines the cultural blend of the runaways with the pictorial representation and its place in the formation of the young protagonists’ identity. In light of these observations, the second part of the thesis will focus on the characters’ awareness of the Other’s perception. The stereotypical suburban teenager lacking culture resulting in the character feeling out of place is being questioned. The breakdown of the “cliché” in the third chapter will address the importance of culture by characters, allowing for a democratization of an upper class culture. The fourth chapter is devoted to the movement of the runaways in space and time. Between the city and its suburbs, the lost paradise that Algeria represents, and the distress of the parents that have left their beloved country, the last part of this study will focus on the characters’ contribution to the rewriting of the history of past and future generations.

Submitted by Hellen Luz (hellencrisluz@gmail.com) on 2017-07-06T18:12:44Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_ControleLocalPotencia.pdf: 10794588 bytes, checksum: ce99108b1f950294c7c989156bcff73d (MD5) / Approved for entry into archive by Irvana Coutinho (irvana@ufpa.br) on 2017-08-18T14:53:16Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_ControleLocalPotencia.pdf: 10794588 bytes, checksum: ce99108b1f950294c7c989156bcff73d (MD5) / Made available in DSpace on 2017-08-18T14:53:17Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_ControleLocalPotencia.pdf: 10794588 bytes, checksum: ce99108b1f950294c7c989156bcff73d (MD5) Previous issue date: 2017-03-31 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Esta dissertação aborda os principais problemas operacionais enfrentados pelos operadores de redes de distribuição devido à elevada integração de geradores fotovoltaicos (FV), tais como sobretensões, comutações excessivas de tape e a condição de runaway em reguladores de tensão. As sobretensões ao longo do alimentador podem ser causadas pela significativa injeção de potência ativa do gerador FV. Adicionalmente, as variações rápidas e significativas na potência ativa injetada pelo gerador FV, associadas com os transitórios de nuvens, resultam em aumento excessivo de comutações de tape no regulador de tensão, afetando negativamente a vida útil desse equipamento. Além disso, quando a direção do fluxo de potência é invertida no alimentador devido à significativa injeção de potência ativa do gerador FV, o regulador de tensão pode falhar no controle da tensão na barra sob regulação e o tape pode atingir seu limite inferior ou superior (condição de runaway). Esta dissertação propõe um controle local de potência reativa para inversores FV a fim de aliviar tais problemas mencionados. O controle proposto é avaliado usando dados de medição de um sistema fotovoltaico real instalado no telhado de uma residência localizada em Belém e simulações dinâmicas de um alimentador de média tensão com uma miniusina FV. / This dissertation addresses the major operational problems faced by distribution network operators due to the high integration of photovoltaic (PV) generators, such as overvoltages, excessive tap counts and voltage regulator runaway condition. The overvoltage problem in distribution networks may be caused by significant active power injection from PV generation. Additionally, the rapid and significant variations in PV generator active power associated with cloud transients result in an increase of voltage regulator tap counts, adversely affecting the useful life of that device. Also, when the direction of the power flow is reversed due to PV generator active power injection, the voltage regulator can fail to control voltage at the regulated bus and reach lowest or highest tap limit (runaway condition). This dissertation proposes a local reactive power control for PV inverters to alleviate such problems. The proposed control is evaluated using measurement data from the real rooftop PV system in the city of Belém and dynamic simulations on a single MV feeder with a PV solar plant.