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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.
241

Cohort and Gender Differences and the Marriage Wage Premium: Findings from the NLSY79 and the NLSY97

Lim, Misun 18 March 2015 (has links) (PDF)
Past research has established a marital wage premium among men, and more recently, among women of the baby boom generation. It is unknown whether: 1) the marriage premium holds among more recent cohorts of men and women, 2) it differs by intensity of work hours among husbands and wives, and 3) cohabiters receive wage bonuses. Using fixed-effects models and data from the 1979-1989 waves of the National Longitudinal Survey of Youth (NLSY79) and the 1997-2010 waves of the National Longitudinal Survey of Youth (NLSY97), this paper compares cohort differences in the gendered marriage premium. While both women and men receive marriage premiums and these premiums are larger for more recent cohorts, men’s premiums are consistently higher and have doubled from the late baby boomers cohort (NLSY79) to the late Generation X (Gen X) cohort (NLSY97). While there was no wage premium for cohabitation among baby boom cohort women, I observe a premium among Gen X men and women. Household specialization matters: while among baby-boomers the marriage premium did not vary by household type, among the Gen X cohort men’s marriage premium is significantly larger among male breadwinner households, and surprisingly, I find marriage penalties for men in female-breadwinner households. Similarly, Gen X female breadwinners and female dual-earners receive the marriage premium while Gen X women in male-breadwinner households experience marriage penalty. In addition, the more highly educated receive larger marital bonuses.
242

Run-time specialization for compiled languages using online partial evaluation / Specialisering av kompilerade språk i körtid med hjälp av online partiell evaluering

Adamsson, Johan January 2024 (has links)
Partial evaluation is a program transformation technique that specializes a program with respect to part of its input. While the specialization is typically performed ahead-of-time, moving it to a later stage may expose additional opportunities and allow for faster residual programs to be constructed. In this thesis, we present a method for specializing programs at run-time, for compiled code, using an online partial evaluator. Although partial evaluation has several applications, the evaluation of the method primarily focuses on its performance benefits. The main research problem addressed in this thesis is that of incorporating an online partial evaluator in compiled code. The partial evaluator is a sourceto-source translator that takes and produces an abstract syntax tree (AST). Our approach consists of three parts, namely that of partially evaluating, obtaining a partially evaluable representation and run-time code emitting. Concretely, we use the concept of lifting to store an AST in the compiled code that the partial evaluator then specializes at run-time. The residual code is thereafter naively just-in-time (JIT) compiled through dynamically linking it back to the executable as a shared library. We evaluate the method on several programs and show that the specialized programs sometimes are faster even with a low recursion depth. Though, while the results are promising, the overhead is typically significant and therefore the break-even points are large. Further research, for example using an efficient JIT compiler, is required to better evaluate the performance benefits of the approach. / Partiell evaluering är en programtransformationsteknik som specialiserar ett program givet delar av dess indata. Typisk sätt specialiseras program innan de exekveras, men genom att flytta specialisering till då programmet körs kan ytterligare information utnyttjas och därmed snabbare residualprogram konstrueras. I det här examensarbetet presenteras en metod för att specialisera program i körtid med online partiell evaluering, specifikt för kompilerade program. Metoden utvärderas främst utefter prestanda, men det ska nämnas att partiell evaluering har fler tillämpningar än så. Det huvudsakliga problemet som examensarbetet undersöker är inkorporeringen av en programspecialiserare (partial evaluator) i kompilerad kod. Den programspecialiserare som används tar både som indata och producerar ett abstrakt syntaxträd (AST). Vårt tillvägagångssätt består av tre delar, nämligen programspecialisering, erhållning av en representation som kan specialiseras och slutligen kodgenerering i körtid. Mer specifikt används konceptet lyftning för att spara ett AST i den kompilerade koden som därefter partiellt evalueras av programspecialiseraren under körtid. Som ett sista steg just-in-time (JIT) kompileras residualprogrammet. Detta görs på ett naivt vis genom att programmet kompileras till ett delat bibliotek som därefter dynamiskt länkas tillbaka till huvudprogrammet. Metoden utvärderas på flera program och vi visar att de specialiserade programmen i vissa fall var snabbare och det även med små rekursionsdjup. Resultaten är lovande, men den overhead som metoden ger upphov till är ofta signifikant vilket gör att det krävs många iterationer innan det specialiserade programmet blir snabbare. Ytterligare forskning och tester, till exempel med en effektiv JIT kompilator, är nödvändig för att bättre kunna utvärdera metodens prestandafördelar.
243

Psykisk ohälsa och elitidrott : Förekomsten av psykosomatiska besvär bland gymnasieelever med inriktning mot elitidrott, idrott respektive utan idrottslig inriktning

Rydberg, Amanda January 2016 (has links)
Psykisk ohälsa bland elitidrottare har varit ett stigmatiserat område och forskning kring ämnet växer. Idag finns mycket som tyder på att elitidrottare utövar en livsstil med stora fysiska och psykiska belastningar vilket har visat sig vara mer ohälsosamt än vad den generella uppfattningen tidigare varit. Som elitidrottare förväntas en att leva efter idrottens alla regler för att bli framgångsrik. I den här uppsatsen studeras förekomst av, och skillnader i psykosomatiska besvär mellan tre grupper av gymnasieelever i årskurs tre som har elitidrottsinriktning (Nationellt godkänd idrottsutbildning, NIU), allmän idrottsinriktning (Idrottsprogram, IDR) och elever utan idrottsinriktning. Det undersöks även om det förekommer samband mellan psykosomat­iska besvär och de olika gymnasiala inriktningarna. Studien har genomförts med en kvant­itativ tvärsnittsstudie med enkäter som delades ut till två skolor i en ort i mellersta Sverige. Totalt deltog 116 elever i undersökningen, med elit- och idrotts- samt utan idrottsinriktning. Resultatet visade att det fanns psykosomatiska besvär hos de olika gymnasiala in­riktning­arna, men inga signifikanta skillnader eller samband fastställdes. Ett intressant biresultat som påträffades är ett signifikant samband mellan att vara nervös och irriterad och att vara stress­ad och ha svårt att sova, samt att sambandet stärktes för samtliga elever att ha nämnda besvär. Nyckelord: Folkhälsa, psykisk ohälsa, psykosomatiska besvär, elitidrott, gymnasieelever, gymnasial idrottsinriktning. / Mental illness among elite athletes has been a stigmatized area and the research area is growing. Today, a lot of things points towards that elite athletes are practicing a lifestyle with great physical and mental tension. Having a profession as an elite athlete has proven to be more unhealthy than the general perception was. As an elite athlete you are expected to live for the sport, to follow its rules in order to achieve a successful career. This study investigates the prevalence of, and differences in psychosomatic disorders between three groups of secondary school students in their last year who have elite sport special­ization (Nationally certified physical education), public sports specialization (sports program) and students without sport specialization. It also investigates whether there is an association between psychosomatic disorders and the three various sport specializations. A quantitative cross-sectional study was performed and a questionnaire were distributed to two schools in central Sweden. A total of 116 students in their 3rd and last year of the secondary school with elite- and sport orientation and without sport orientation participated in the survey. The results showed a difference in the prevalence of psychosomatic disorders among the various orientations in secondary school. Eventhough no significant diff­erences or associations between psychosomatic disorders and secondary school orientation was found, a secondary finding was found in the form of significant correlations for the student to be nervous and irritated with being stressed and having trouble falling asleep, and the associations became stronger for students having these problems. Keywords: Public health, mental disorder, psychosomatic disorder, elite sports, secondary school students, secondary school sport specialization.
244

審計委員會與財務主管相對影響力對會計師產業專精委任之關聯性 / The Relative Power of Audit Committee to CFO and auditor’s industry specialization

李佳芷 Unknown Date (has links)
本文以2005年至2014年間中華人民共和國上海及深圳上市公司為研究對象,參照Beck and Mauldin (2014)衡量審計委員會與財務長之間相對影響力之模式,從公司治理觀點分析選任個人層級及事務所層級之產業專家會計師,是否與審計委員會相較於財務主管較具有影響力有關聯性,並參考過去發展的文獻,以多種衡量產業專家之方法執行敏感性分析。本研究結果顯示,當企業之審計委員會相較於財務主管之相對影響力較大時,與個人層級之產業專家及同時為個人層級及事務所層級之產業專家會計師具有顯著正相關、與會計師事務所層級之產業專家呈現不顯著相關,故可推論,審計委員會相對較有影響力時會傾向選擇會計師個人產業專家。 / The primary objective of this thesis is to examine whether and how the relative power of the CFOs to audit committee affects the choice of auditor’s industry specialization, measured as firm level and partner level. We focus my analyses on a sample of listed firms in China during 2005-2014. We follow the measure of the relative power of CFO and audit committee by Beck and Mauldin (2014) to test my predictions. My main findings can be summarized as follows. First, the thesis finds evidence that firms are more likely to choice firm-level audit experts when its CFO is less powerful than audit committee. Second, it also finds that firms are more likely to hire partner-level audit experts when audit committee is relatively powerful than the CFO. The results are robust to other proxies for audit experts.
245

Les locuteurs d’une langue tonale sont-ils de meilleurs musiciens? Effet potentiel de la connaissance native d’une langue à tons sur la perception du contraste du pitch

Li, Na 11 1900 (has links)
Ce mémoire consiste à offre un survol des études neuropsychologiques et électrophysiologiques concernant l’interaction possible entre le traitement du langage et la musique. Le but principal est de déterminer les raisons possibles pour lesquelles des locuteurs d’une langue à tons auraient une meilleure capacité dans la perception du contraste du pitch en musique par rapport aux individus qui ont pour langue maternelle une langue à intonation. Dans un premier temps, nous discutons du traitement neuronal de la prosodie et de la musique, tentant de montrer le chevauchement du traitement cérébral des deux domaines. Ensuite, nous présentons des notions d’une langue tonale ainsi que le traitement neuronal des tons lexicaux. Après, nous discutons des effets de transfert de la capacité du traitement du pitch en linguistique et en musique, en nous focalisant sur l’influence de la connaissance native d’une langue tonale sur la perception musicale. Pour ce faire, l’encodage du pitch et la localisation hémisphérique du traitement des tons lexicaux et la musique serons discutés. / This thesis gives an overview of neuropsychological and electrophysiological studies about the possible interaction between the processing of language and music. Our main purpose is to examine the possible reasons for which tone language speakers have a better capacity in perceiving pitch contrast in music than native speakers of an intonational language. First, we discuss the neural processing of prosody and music, attempting to show an overlap between the two domains. Next, we present the concept of a tone langue and the neural processing of lexical tones. Afterwards, we discuss the transfer effects of the processing capacity of pitch in linguistic and music by focusing on the influence of a knowledge of a tone language on the musical perception. To do this, the encoding of pitch and the hemispheric specialization will be discussed.
246

Ecology and Evolution of Adaptive Morphological Variation in Fish Populations

Svanbäck, Richard January 2004 (has links)
The work in this thesis deals with the ecology and evolution of adaptive individual variation. Ecologists have long used niche theory to describe the ecology of a species as a whole, treating conspecific individuals as ecological equivalent. During recent years, research about individual variation in diet and morphology has gained interest in adaptive radiations and ecological speciation. Such variation among individual niche use may have important conservation implications as well as ecological and evolutionary implications. However, up to date we know very little about the extension of this phenomenon in natural populations and the mechanisms behind it. The results in this thesis show that the extension of individual diet specialization is widely spread throughout the animal kingdom. The variation in diet is mainly correlated to morphological variation but not always. Furthermore, this variation in diet and morphology among individuals could be both genetically determined and environmentally induced and it mainly comes from trade-offs in foraging efficiency between different prey types. The results from a number of studies of perch also show that individual perch differ in morphology and diet depending on habitat, where littoral perch has a deeper body compared to pelagic perch. This difference in morphology corresponds to functional expectations and is related to foraging efficiency trade-offs between foraging in the littoral and pelagic zone of a lake. The variation in morphology in perch is mainly due to phenotypic plasticity but there are also small genetic differences between the littoral and pelagic perch. Two separate studies show that both predation and competition may be important mechanism for the variation in morphology and diet in perch. In conclusion, the results in this thesis show that individual variation in diet and habitat choice is a common phenomenon with lots of ecological and evolutionary implications. However, there are many mechanisms involved in this phenomenon on which we are just about to start learning more about, and only further research in this area will give us the full insight.
247

Neuroimagerie fonctionnelle du langage et de la mémoire chez des personnes ayant des atteintes neurologiques

Pelletier, Isabelle 02 1900 (has links)
Les objectifs de ce programme de recherche étaient, d’une part, d’apporter une compréhension critique des techniques non-invasives utilisées dans la localisation et/ou la latéralisation des aires langagières et mnésiques en tenant compte de leurs avantages, de leurs limites propres ainsi que de leur pertinence dans un contexte clinique. D’autre part, d’approfondir notre compréhension de l’organisation cérébrale langagière auprès d’une population de sujets ayant une agénésie du corps calleux en utilisant un protocole de neuroimagerie. Afin de répondre à notre premier objectif, une revue critique de la littérature des méthodes de neuroimagerie utilisées pour la latéralisation et la localisation des aires cérébrales sous-tendant le traitement langagier et mnésique dans le contexte du bilan préchirurgical des patients épileptiques a été effectuée. Ce travail a permis d’identifier que certaines de ces nouvelles techniques et plus spécialement leur combinaison, montrent un potentiel réel dans ce contexte clinique. Cette recherche a également permis de mettre en lumière que ces méthodes ont encore un grand besoin d’être raffinées et standardisées avant d’être utilisées comme remplacement au test à l’amobarbital intracarotidien dans un contexte clinique sécuritaire. Afin de répondre à notre deuxième objectif, nous avons exploré les patrons de latéralisation du langage auprès de six sujets acalleux en utilisant un protocle d’imagerie par résonance magnétique fonctionnelle (IRMf). Les résultats indiquent que les individus ayant une agénésie du corps calleux montrent un patron d’activation cérébrale tout aussi latéralisé que nos deux groupes contrôles (QI apparié et QI élevé) lors du traitement du langage réceptif. Les sujets ayant une agénésie du corps calleux montrent également un patron de latéralisation comparable à leur groupe contrôle apparié pour le QI pour la tâche de langage expressif. Lorsque l’on compare les sujets ayant une agénésie du corps calleux au groupe contrôle de QI élevé, ces derniers montrent une latéralisation moins marquée uniquement pour la région frontale lors de la tâche de langage expressif. En conclusion, les résultats de cette étude ne supportent pas l’affirmation que le corps calleux jouerait un rôle inhibiteur essentiel afin de permettre un développement normal de la latéralisation hémisphérique pour le langage. / The goals of this research program were, on the one end, to bring a critical understanding of the non invasive techniques used for the localisation and lateralisation of language and memory functions taking into account their respective advantages, limits and relevance in a patient care context. On the other end, we wanted to deepen our understanding of cerebral language organization in the context of the study of acallosal subjects. To meet our first objective, we performed a comprehensive review of the litterature of neuroimaging methods used in language and memory lateralisation and localisation in the context of presurgical assessment of epileptic patients. In this work, we pointed out that some of these new methodologies and moreover their combinations show an interesting potential for the use in a clinical context. We also pointed out that these methods still need to be refined and standardised before replacing the intracarotid amobarbital test in a safe clinical setting. To meet our second objective, we explored patterns of language lateralization in six individuals with callosal agenesis using a functional magnetic resonance imaging (fMRI) protocol. No differences were found between language lateralization of subjects with agenesis of the corpus callosum and the control groups (High-IQ and IQ-matched) in the receptive speech task. However, for expressive speech, the groups differed with respect to frontal activations, with the acallosal participants showing a more bilateral pattern of activation than the high-IQ participants only. No differences were found in themporal regions. Overall, these results indicate that the corpus callosum is not essential for the establishment of lateralized language functions.
248

Les mesures du regroupement spatial des populations : aspects méthodologiques et applications aux grandes aires urbaines françaises / Measurement of population spatial clustering : theory aspect and application to the French urban area

Dasré, Aurélien 04 December 2012 (has links)
L’étude des phénomènes de regroupement spatial des individus en milieu urbain se focalisesouvent sur les espaces les plus fortement polarisés, qu’il s’agisse des « ghettos » de « riches » ou de« pauvres ». Pourtant, ces quartiers ne représentent qu’une partie très congrue de l’espace urbainfrançais. Sans occulter l’existence de ces zones, ce travail se propose d’étudier les phénomènes deregroupement spatial sous un angle exhaustif. Ceci a nécessité le développement d’une méthodologiepermettant de rendre compte de la complexité de la spécialisation socioéconomique etsociodémographique des territoires. L’impact de l’échelle géographique retenue dans les analyses surles résultats aussi bien en terme d’intensité que d’évolution est ainsi apparu comme une donnéecentrale de la problématique. En se basant sur cette analyse comparative des échelles géographiquesde regroupement, ce travail dresse un panorama des profils de regroupements des individus dans 18aires urbaines françaises. Il est ainsi apparu qu’il existe une grande similarité de ces phénomènes entreles grandes villes. Les individus s’y distribuent selon un modèle sectoriel d’un point de vuesocioéconomique quand ils suivent un schéma concentrique d’un point de vue sociodémographique.La combinaison de ces deux logiques a ainsi permis une analyse globale des phénomènes deregroupement socio-spatial. / The study of spatial clustering’s phenomena of people in zones often focuses on the moststrongly polarized spaces, it can be about "ghettos" of "rich" or "poor people". Nevertheless, theseareas represent a small part of the French urban space. Without denying the existence of these zones,this work will study the phenomena of spatial clustering from an exhaustive point of view. Thisrequired the development of a methodology allowing to take into account the complexity of thesocioeconomic and sociodemographic specialization of territories. The impact of the geographicalscale selected in analyses, on the results both in term of intensity and evolution is turned to be acentral topic of the problematic. By basing itself on this comparative analysis of the geographicalscales of clustering, this work gives an overview of the clustering profiles in 18 French urban areas. Itappeared that there is a similarity of these phenomena between big cities. Human distributions followa sectorial model on a socioeconomic point of view when they follow a concentric model bysociodemographic variables. The combination of these two paradigms of grouping so allowed a globalanalysis of the phenomena of socio-spatial clustering.
249

Le commerce intra-national et international des Etats Brésiliens : déterminants, structure et interdépendances / International and Intra-national Trade of Brazilian States : Determinants, Structure and Interdependencies

Yücer, Ayçil 26 November 2012 (has links)
Cette thèse a pour ambition de transposer l'analyse du commerce international au niveau sub-national en examinant la structure et les déterminants du commerce entre états brésiliens, et avec les marchés internationaux. Dans un chapitre introductif, on présente les faits stylisés sur la le commerce brésilien en se concentrant essentiellement sur les caractéristiques des états brésiliens. Dans le premier chapitre, notre modèle de gravité, estime séparément les capacités d'exportation des états vers les marchés domestique et international. Les résultats montrent que les états les mieux classés en termes de capacités d'exportation vers le marché international ne se confondent pas avec les plus orientés vers le marché domestique. Dans le second chapitre, on utilise un modèle de gravité pour mettre en évidence les effets de création et de détournement de commerce ainsi qu’un un effet d’ « érosion des préférences ». Nous montrons que le MERCOSUR a permis d’augmenter le commerce des états avec les pays membres, sans effets significatifs sur le commerce inter-états ou avec les pays tiers. Les organisations internationales, suggèrent que le commerce en valeur ajoutée est une meilleure mesure pour analyser l’impact des échanges internationaux sur l’économie quand le contenu en importations des exportations est important. Dans un dernier chapitre, on calcule ainsi les valeurs ajoutées exportées des états brésiliens à partir d’un tableau Input-Output inter-états (2008) pour analyser et mesurer les spécialisations verticales entre les états. On estime également un modèle de gravité de commerce en valeur ajoutée qu’on élargit à un cadre trilatéral: l’état d’origine, l’état ré-exportateur et le pays importateur. / With the ambition of transposing trade analysis to an intra-national level, we work on the determinants and the structure of trade among Brazilian states, as well as their trade with international markets. In an introductory chapter, we present the stylized facts concerning the Brazilian trade while focusing mainly on the states’ characteristics. In chapter 1, we estimate the states’ domestic and foreign market export capacities by a gravity model of trade. Results show that the states with better foreign export capacities are not necessarily the same as those more oriented to the domestic market. Then in the second chapter, we use a gravity model to shed light on MERCOSUR’s creation and diversion effects as well as its “preference erosion” effect on trade among Brazilian states. We show that MERCOSUR increased Brazilian states’ trade with member countries, but had no significant effect on either interstate trade or Brazilian states’ trade with third countries. International organizations suggest the trade in value-added would be a “better” measure to understand the impact of trade on economy when import content in exports is important. Hence in a last chapter, we calculate the value-added exported by Brazilian states from an inter-state Input-Output table (2008) that we use to analyze and measure the vertical specialization between states. We also estimate a gravity model of trade in exported value-added that we extend to a trilateral frame: origin state, re-exporter state and importer country.
250

VLIV ROSTOUCÍ POKRYVNOSTI INVAZNÍHO TRNOVNÍKU AKÁTU NA PTAČÍ SPOLEČENSTVA V LESNÍCH POROSTECH / THE EFFECT OF AN INCREASING COVERAGE OF INVASIVE BLACK LOCUST ON BIRD COMMUNITIES IN FOREST STANDS

Kroftová, Magdalena January 2016 (has links)
Biological invasions are one of the most important threats to global biodiversity and they were also found to negatively affect some bird species. Despite relatively large number of scientific studies dealing with the impacts of invasive plants on bird communities, their results are inconsistent, especially it is not clear how birds respond to increasing levels of expansion of invasive species in native species stands. Moreover, bird responses to plant invasions seem to depend on the ecological characteristics of individual bird species. This study contributes to elucidation of this problem; I investigated the impacts of black locust (Robinia pseudoacacia) invasion on bird communities in three types of forest stands with different levels of invasion: in stands containing solely the native oak (Quercus spp.), in partially invaded stands with different proportions of black locust and oak (mixed stands) and in pure black locust stands. Previous studies that examined birds in pure oak and pure black locust stands have found that they differ markedly in vegetation structure, but not in the total number of bird species. However, habitat specialists were associated with the oak stands, while generalists with the black locust stands. Therefore, I predicted that (1) the total species richness will be...

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