Thesis (PhD (Electrical and Electronic Engineering)--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: A monostatic baseband radar is required with the capability of detecting close range targets that appear at distances comparable to the system’s resolution, without compromising the radar’s maximum range. The application in borehole radar imposes further constraints associated with the physical limitations and variable electromagnetic environment of different borehole diameters and conditions. This dissertation discusses the complete design process of the analog section of a monostatic radar that successfully addresses these issues. The proposed transceiver employs a series duplexing arrangement consisting of an antenna, transmitter, receiver and an isolation switch. An exponentially decaying tail is observed in the current flowing on a borehole radar antenna when excited by pulse waveforms. The characteristics of this tail depend strongly on the borehole environment. A measurement technique is developed that accurately quantifies this exponential decay by digitizing a logarithmic representation of the antenna current while it is operating in various boreholes. Transmitters are then designed to drive these antennas with waveforms that prevent the formation of current tails. This is achieved through the use of pole-zero networks or alternatively by generating certain asymmetric, bipolar waveforms. The transmitters are simultaneously designed to have an output impedance approximating a short circuit after the transient is generated. In the series configuration proposed here, the duplexing of the antenna between transmitter and receiver is then reduced to simply isolating the receiver during transmit-mode. The switch responsible for this isolation disconnects the receiver and presents a short circuit between antenna and transmitter during transmit-mode, while connecting the receiver terminals between the antenna and the short circuited transmitter terminals in receive-mode. The required close-in performance of the transceiver dictates that the transition between these two states of the isolation switch occur in a time similar to the duration of the transmitter waveform. The switching artefacts generated by the switch are consequently similar to the radar data signal. The isolation switch employs an innovative configuration (using both transistors and diodes) which accepts a single control signal and causes the switching artefacts to be generated as a common mode signal, while a differential path is created for the radar data signal which is being switched. This leads to effective suppression of the switching signal in the signal passed to the receiver. Dissipative filtering is advocated as a fundamental design principle for high fidelity receivers and it is shown how it can be applied by using constant impedance equalizers and diplexers as basic building blocks. This principle is used as the basis for the design of this transceiver's receivers, which incorporate both standard gain blocks and operational amplifiers. A complete borehole radar system, based on the transceiver developed here, was built and tested; resulting in the first known practical monostatic borehole radar system. Data obtained in field trials are presented and suggest that the monostatic system compares well with current state of the art bi-static systems. / AFRIKAANSE OPSOMMING: Die behoefte is geïdentifiseer vir 'n monostatiese basisbandradar wat oor die vermoë beskik om nabygeleë teikens op 'n afstand soortgelyk aan die resolusie van die stelsel waar te neem, sonder om die maksimum bereik van die stelsel in te kort. Die toepassing daarvan in 'n boorgatradarstelsel lei tot verdere vereistes vanweë die fisiese beperkings en veranderende elektromagnetiese omgewing van boorgate met verskillende deursnitte en toestande. Hierdie proefskrif is gemoeid met die volledige ontwerpsprosedure van die analoog gedeelte van 'n monostatiese radar wat al hierdie kwessies aanspreek. 'n Serie verbinding van antenne, sender, ontvanger en isolasieskakelaar word ingespan vir hierdie ontwerp. Eksponensieel wegsterwende stertjies word waargeneem in die antennestroom van 'n boorgatradarantenne wanneer dit aangedryf word deur puls golfvorms. 'n Meettegniek word ontwikkel wat hierdie eksponensiële verslapping noukeurig kan monitor deur 'n logaritmiese voorstelling van die antennastroom te versyfer terwyl dit ontplooi word in verskillende boorgate. Senders word dan ontwikkel om hierdie antennes aan te dryf met golfvorms wat juis die vorming van hierdie stertjies voorkom. Dit word bewerkstellig deur die gebruik van pool-zero netwerke of andersins deur die opwek van sekere asimmetriese, bipolêre golfvorms. Die senders se uittree-impedansies moet egter terselfdertyd ontwerp word om 'n kortsluiting te benader sodra die oorgang klaar opgewek is. Met die serie verbinding wat hier gebruik word, raak die vereiste tyddeling van die antenna tussen die sender en ontvanger dan bloot 'n geval van ontvanger-isolasie gedurende uitsaai-modus. Die skakelaar wat verantwoordelik is vir hierdie isolasie ontkoppel die ontvanger en vertoon soos 'n kortsluiting tussen sender en antenne tydens uitsaai-modus, maar verbind weer die terminale van die ontvanger tussen die antenne en kortgeslote senderterminale tydens ontvang-modus. Die vereiste kortafstand vermoë van die stelsel veroorsaak dat die tysduur van die oorgang tussen hierdie twee modusse soortgelyk is aan dié van die sender golfvorm en enige skakelverskynsels wat opgewek word deur die skakelaar is gevolglik soortgelyk aan die radardatasein self. Die isolasieskakelaar gebruik egter 'n innoverende konfigurasie (met transistors sowel as diodes) wat funksioneer met 'n enkele beheersein en die skakelverskynsels as gemene modus seine opwek, terwyl 'n differensiële seinpad geskep word vir die radardatasein wat geskakel word. Die skakelseine word gevolglik effektief onderdruk in die sein wat oorgedra word aan die ontvanger. Die gebruik van verkwistende filters word voorgestel as 'n fundamentele ontwerpsbeginsel vir hoëtrou ontvangers en daar word getoon hoe dit toegepas kan word met konstante impedansie vereffeningsbane en dipleksers. Hierdie beginsel is dan ook gebruik as basis vir die ontwerp van hierdie stelsel se ontvangers, wat gebruik maak van beide standard aanwinsblokke sowel as operasionel versterkers. 'n Volledige boorgatradarstelsel, gebaseer op die stelsel wat hier ontwikkel is, is gebou en getoets. Die gevolg is die eerste bekende, praktiese monostatiese boorgatradarstelsel. Data wat hiermee verwerf is word aangebied en dui daarop dat die monostatiese stelsel baie goed opweeg teen huidige bi-statiese stelsels.

In this dissertation, we present three complementary studies of the processes that drive planetary migration. The first is a radial-velocity survey in search of giant planets in adolescent (<1 >Gyr) open clusters. While several different mechanisms may act to drive giant planets inward, only some mechanisms will excite high eccentricities while doing so. Measuring the eccentricities of young hot Jupiters in these clusters (at a time before the orbits have had a chance to circularize due to tidal friction with their host stars) will allow us to identify which mechanisms are most important. Through this survey, we detect the first 3 hot Jupiters in open clusters (and at least 4 long-period planets), and we measure the occurrence rate of hot Jupiters in clusters to be similar to that of the field (~1%). We determine via analyses of hot Jupiter eccentricities and outer companions in these systems that high eccentricity migration mechanisms (those requiring the presence of a third body) are important for migration. The second project, an adaptive optics imaging survey for stellar companions to known hot Jupiter hosts, aims to determine the role that stellar companions in particular play in giant planet migration. Through a preliminary analysis, we derive a lower limit on the binary frequency of 45% (greater than that of the typical field star), and we find that the presence of a companion is correlated with misalignment of the spin-orbit angle of the planetary system, as would be expected for stellar Kozai-Lidov migration: at least 74% of misaligned systems reside in binaries. We thus conclude that among high eccentricity migration mechanisms, those requiring a stellar companion play a significant role. Finally, we describe simulations of measurements of the planet population expected to be discovered by TESS, and use these to demonstrate that a strong constraint on the obliquity distribution of small planets can be derived using only TESS photometry, Gaia astrometry, and vsin(i) measurements of the host stars. This obliquity distribution will be a key piece of evidence to help detemine the likely formation and migration histories of small planets, and can contribute to the assessment of the potential for Earth-like planets to harbor life.

Bakgrund: Palliativ vård handlar om att ge stöd till patienten och anhöriga under och efter vårdtiden. De ”6 s:n” är en arbetsmodell inom palliativ vård där patienten har rätt till självbestämmande och att upprätthålla sina sociala relationer, även stöd till anhöriga ingår. Anhöriga har en betydelsefull roll i den palliativa vården, deras närvaro skapar möjlighet för den döende att vara hemma i livets slutskede. Syfte: Syftet var att beskriva anhörigas upplevelse av palliativ vård i hemmet under livets slutskede. Metod: Litteraturöversikt baserad på 15 vetenskapliga artiklar från fem olika länder med kvalitativ ansats. Resultat: Fem kategorier identifierades kopplade till anhörigas upplevelser: Palliativa teamets inträde i hemmet, anhörigas vårdansvar, den medicintekniska utrusningens inverkan på vardagslivet, känslor och konsekvenser för anhöriga samt förbättringsmöjligheter och anhörigas uppfattning om palliativ vård. Slutsats: Anledningen till anhörigas vårdansvar var löftet att få dö hemma, uppgiften upplevdes krävande och gav konsekvenser på sömnen och deras fysiska och psykiska mående. Detta var genomgående i hela litteraturöversikten. Vården i hemmet sågs som den rätta platsen att dö på för alla parter, endast en anhörig uttryckte avsky för situationen. Enligt anhöriga var stödet bra dock fanns det ett ökat behov av mer resurser för fullständig trygghet. / Background: Palliative care is about providing support to both the patient and family during and after the time of care. The “6 s:n” is a working model in palliative care where the patient has the right to self-determination and to maintain their social relationships, which includes support to relatives. Relatives have an important role in palliative care, their present creates opportunity for the dying person to be at home in the final stages of life. Aim: The aim of this study was to describe relative’s experiences of palliative home care during the final stage of life. Methods: A literature review based on 15 scientific articles from five different countries with a qualitative approach. Results: Five categories were identified related to relatives experiences: The entry of palliative home care, relatives caring role, the impact of medical technology on everyday life, feelings and consequences for relatives and also improvement opportunities and relatives comprehend about palliative home care. Conclusions: The promise was the reason for relatives caring role, the caring role was an demanding task and gave impacts on their sleep and their physical and mental needs. This was consistently throughout the whole literature review. For all parties the home was seen as the right place to die, only one relative expressed disgust for the situation. According to relatives the support was good, but to complete full security for them it was an increased need for more resources.

This thesis investigates single pole reclosing in series capacitor compensated line. An algorithm is developed to determine the optimal dead time required for single pole reclose of circuit breakers and to reduce the randomness of reclosing time. The algorithm considers conditions of system, fault, voltage zero crossing, arc, and IEEE C37.104-2012 standard de-ionization time. This study also addresses difficulties of single pole reclose operation such as over-voltages at the line, secondary arc extinguishing time, dead time, over-voltages across the series capacitor, and negative sequence current. The system performance is evaluated using a set of metrics based on those operation difficulties. Methods used in the industry such as shunt reactor with the neutral reactor, surge arrester, and MOV are modelled and simulated to capture their effect on the operation difficulties. Comparative analysis is made to rank the effectiveness of each element against difficulties in operating single pole reclosing of circuit breakers.

Stellar companions can influence the formation and evolution of planetary systems, but there are currently few observational constraints on the properties of planet-hosting binary star systems. We search for stellar companions around 77 transiting hot Jupiter systems to explore the statistical properties of this population of companions as compared to field stars of similar spectral type. After correcting for survey incompleteness, we find that 47% +/- 7% of hot Jupiter systems have stellar companions with semimajor axes between 50 and 2000 au. This is 2.9 times larger than the field star companion fraction in this separation range, with a significance of 4.4 sigma. In the 1-50 au range, only 3.9(-2.0)(+4.5)% of hot Jupiters host stellar companions, compared to the field star value of 16.4% +/- 0.7%, which is a 2.7 sigma difference. We find that the distribution of mass ratios for stellar companions to hot Jupiter systems peaks at small values and therefore differs from that of field star binaries which tend to be uniformly distributed across all mass ratios. We conclude that either wide separation stellar binaries are more favorable sites for gas giant planet formation at all separations, or that the presence of stellar companions preferentially causes the inward migration of gas giant planets that formed farther out in the disk via dynamical processes such as Kozai-Lidov oscillations. We determine that less than 20% of hot Jupiters have stellar companions capable of inducing Kozai-Lidov oscillations assuming initial semimajor axes between 1 and 5 au, implying that the enhanced companion occurrence is likely correlated with environments where gas giants can form efficiently.

Measures of adult attachment developed in English have been translated and validated in multiple Spanish-speaking countries, yet to this date no self-report adult attachment instrument has been systematically examined for validation with Latinos/Hispanic Americans. The present study examined psychometric properties of a Spanish version of a widely used adult attachment scale, the Experiences in Close Relationships Scale (ECRS), with a bilingual college student sample. Following the dual-language split half (DLSH) quantitative method of evaluating semantic equivalence, 209 bilingual, Latinos/Hispanic American college students recruited from a large public university completed a DLSH version of the ECRS (half English, half Spanish). Internal consistency reliability and DLSH reliability were within acceptable limits, although significantly smaller than coefficients of the English ECRS completed by a large Caucasian sample (n = 459); 3- to 8-week test-retest reliability was also adequate. Exploratory factor analysis revealed a two-factor solution with 35 items accounting for 40% of the variance, which was similar to the English ECRS. Convergent validity was supported by findings that showed significant associations of attachment dimensions with social self-efficacy, self-esteem, depressive symptoms, and comfort with self-disclosure, but not interpersonal trust. Evidence for discriminant validity was found in that attachment dimensions were not significantly associated with social desirability. Theoretical implications, limitations, and future directions of the study will be discussed based on adult attachment theory and cross-cultural perspectives.

Some close-in gaseous exoplanets are nearly in Roche lobe contact, and previous studies show that tidal decay can drive hot Jupiters into contact during the main sequence of their host stars. Improving on a previous model, we present a revised model for mass transfer in a semidetached binary system that incorporates an extended atmosphere around the donor and allows for an arbitrary mass ratio. We apply this new formalism to hypothetical, confirmed, and candidate planetary systems to estimate mass-loss rates and compare with models of evaporative mass loss. Overflow may be significant for hot Neptunes out to periods of similar to 2 days, while for hot Jupiters, it may only be important inward of 0.5 days. We find that CoRoT-24 b may be losing mass at a rate of more than an Earth mass in a gigayear. The hot Jupiter WASP-12 b may lose an Earth mass in a megayear, while the putative planet PTFO8-8695 orbiting a T Tauri star might shed its atmosphere in a few megayears. We point out that the orbital expansion that can accompany mass transfer may be less effective than previously considered because the gas accreted by the host star removes some of the angular momentum from the orbit, but simple scaling arguments suggest that the Roche lobe overflow might remain stable. Consequently, the recently discovered small planets in ultrashort periods (< 1 day) may not be the remnants of hot Jupiters/Neptunes. The new model presented here has been incorporated into Modules for Experiments in Stellar Astrophysics (MESA).

The topic of this thesis is virtual death in video games. In theoretical part, the concept of avatar (player's agent in the game world) is defined, concerning the relationship between player and avatar as well as the main characteristics of the avatar. The aim of the theoretical core of this thesis is to introduce virtual death; because of various expressions of death in many games, it is difficult to describe virtual death generally. Virtual death, which is compared also to the real death, is revealed as a communication of player's failure. What can not be separated from virtual death is the instant resurrection of the avatar, and also the means how to avoid virtual death. The practical part of the thesis offers a close reading of the computer role-playing game Planescape: Torment, focusing on the theme of death. Unlike most mainstream games, Torment presents the player with sophisticated perspectives on the matters of life, death, immortality and responsibility. Even the high-order goal of the main character (which becomes the goal of the player as well) is to gain knowledge about himself and then willingly die. This stands in a sharp contrast to usual narratives, forcing the player to suppress the life-saving reflex and let his avatar die in the end. The comparative method is used to identify...

Sweden like other Nordic countries are cited as models in terms of gender equality in the world. In addition, they played a significant role in the process of changing the Declaration on eradication of discrimination against women (CEDAW) into a binding Convention. However, the report Captured Queen on men’s violence against women published by Brottsoffer-myndigheten (The Crime Victim Compensation and Support Authority) in 2001 showed the extend of this issue of society in Sweden. The purpose of this thesis is to explore how the situation of men’s violence against women in close relationships in Sweden is presented today since the publication of the report Captured Queen in 2001.The theoretical framework consists of the feminist perspectives and concept of hegemonic masculinities. Qualitative method and secondary materials were used to gain a deeper understanding of the issue of men’s violence against women in close relationships in Sweden. The main findings of this thesis show that men’s violence against women in close relationships is a real social problem in Sweden. There is no specific profile of violent men against women in Sweden, since they come from all social classes, backgrounds and of all ages. Men’s violence against women can be explained by the result of inequalities between men and women in social structures. It is this social and collective domination of women by men that facilitate the individual domination of a man over his partner. Therefore, factors such as alcohol consumption cannot be the determinant cause of men’s violence against women. Nonetheless, alcohol consumption constitutes a factor that can promote or increase the likelihood of violence. The latest Swedish sexual assault legislation based on consent entered in force the first July 2018 cannot significantly reduce the extent of this social phenomenon, since social structures in Sweden are based on patriarchal considerations where men dominate over women.

Esta pesquisa tem por objetivo estudar os fenômenos de contato entre línguas que surgem nas interações entre aprendizes de italiano como língua estrangeira (LE), cuja língua materna (L1) é o português-brasileiro, durante a realização em dupla de uma tarefa (task) escrita. Em especial, analisam-se as estratégias de compensação denominadas conscious transfer que incluem a inserção de regras e termos da L1 na L2, classificadas como estratégias utilizadas pelos falantes para fazerem frente a problemas de comunicação em LE. São elas: a troca de código, os estrangeirismos, a tradução literal e o transfer. Para garantir a naturalidade dos dados, decidimos levantá-los num contexto autêntico, ou seja, na aula de língua estrangeira. O corpus que compõe este estudo é formado por 15 horas de gravações, posteriormente transcritas, realizadas numa classe formada por seis aprendizes de nível B2, inscritos no programa do curso de graduação em Língua e Literatura Italiana de uma universidade do Estado de São Paulo. Para classificar e analisar as estratégias de comunicação presentes nas interações de aprendizes cuja L1 é próxima à LE, valemo-nos da taxonomia proposta por Dörnyei e Kormos (1998), que procura conciliar a perspectiva psicológica com a perspectiva sociointeracional. A abordagem adotada para a análise das sequências dialógicas situa-se num espaço de confluência de disciplinas como a etnografia, a análise da conversação e os estudos interacionistas. Da análise do corpus emerge que os aprendizes, para realizar uma tarefa, optaram pelo uso da língua alvo em lugar da L1. A existência de um controle menor por parte do professor aumentou a ocorrência das atividades de natureza metalinguística, porque estimulou os interactantes, na tentativa de serem entendidos, a melhorarem seu output por meio de um conjunto de auto e heterocorreções. Entretanto, o uso das estratégias denominadas conscious transfer não visa somente à superação de determinados obstáculos linguísticos. Com efeito, a interlíngua dos aprendizes observados é caracterizada por um espaço dinâmico, híbrido e em construção, um espaço disputado entre o exolinguismo, constituído por todas as estratégias que servem para compensar as lacunas linguísticas devidas à falta de recursos adequados para expressar-se em LE, e o bilinguismo, caracterizado seja por estratégias discursivas seja por estratégias eminentemente expressivas, realizadas por meio da L1 ou, por que não dizer, da L3 e L4, destinadas à obtenção de um tipo de efeitos e de funções comunicativas que a LE não possui. Portanto, seria oportuno falar mais de estratégias de comunicação plurilíngue do que de estratégias de compensação. À luz dos dados levantados, podemos afirmar que, mesmo quando o contexto poderia induzir os alunos a utilizarem com maior probabilidade a L1, não há razões que justifiquem o receio manifestado por professores e alunos, porque, dependendo do tipo de atividade realizada, é provável que seja iniciado um processo de negociação que, sem dúvida, levará ao enriquecimento e à construção da interlíngua. / This research aims to study phenomena of contact between languages that arise in the interactions between learners of Italian as a second language (L2), who have Brazilian Portuguese as first language (L1), while executing a written task in pairs. In particular, we analyze the compensation strategies called conscious transfer that include the insertion of rules and terms of L1 on L2, classified as strategies used by speakers to face communication problems in LE. Namely, they are: code switch, loanwords, literal translation, and transfer. In order to guarantee the data naturalness, we have decided to collect them in an authentic context, that is, in the L2 classroom. The corpus that constitutes this study is comprised of 15 hours of records, which thereafter have been transcript, taken in a class formed by six learners of level B2, enrolled in the undergraduate program of Italian Language and Literature at a university of the state of São Paulo, Brazil. For the purpose of classifying and analyzing the communication strategies present in the interactions of learners whose L1 is akin to L2, we used the taxonomy proposed by Dörnyei e Kormos (1998), which intends to reconcile the psychological perspective with the socio-interactive one. The approach adopted for the analysis of dialogical sequences is situated in a space of confluence between disciplines such as ethnography, conversation analysis, and interactionist studies. The analysis of the corpus shows that the learners, in order to accomplish a task, have opted for using the target language instead of L1. The existence of less control by the teacher has increased the occurrence of metalinguistic activities, because it stimulated the interactants, as they tried to be understood, to improve their output by means of a combination of self- and hetero-corrections. However, the use of strategies the compensation strategies called conscious transfer does not seek only to overcome specific linguistic obstacles. Indeed, the interlanguage of the observed learners features a dynamic and hybrid space in permanent construction, a space disputed by exolinguism comprised of all the strategies for compensating linguistic gaps due to the lack of proper resources to express oneself in L2 and bilinguism characterized by discursive strategies as well as by eminently expressive ones, which are accomplished using L1 or, so to speak, L3 and L4, and destined to obtaining a kind of effects and communicative functions that L2 does not possess. Therefore, we are convinced that it is more a case of plurilingual communication strategies than of compensation strategies. In light of the collected data we can state that, even when the context could induce a greater probability that learners used L1, there are no reasons that justify the concern manifested by teachers and students, because depending on the type of activity performed, it is probable that it will be initiated a process of negotiation that, with no doubt, shall lead to an enrichment and to the construction of interlanguage.