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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.
411

The Politicization of Juvenile Delinquency and Juvenile Justice in Sweden; Towards a Culture of Control

Hådell, Nathalie January 2024 (has links)
This thesis examines the politicization of juvenile delinquency and juvenile justice in Sweden since 1989, and explores problem representations of prevalence within the recently proposed penal reforms to reduce the minimum age of criminal responsibility, implement stricter regulations for young offenders, and establish youth prisons. Specifically, this thesis aimed to investigate whether efforts to address the issue of juvenile delinquency are an effect of crisis-based politicization, and if the recently proposed penal reforms reflect the identified global trend of defending old and retaliatory principles of juvenile justice.  The research was conducted by applying a comprehensive theoretical framework, including politicization theory and the perspectives of humane neoclassicism, hegemonic neoliberalism and cultures of control, combined with a single case study design, including process tracing and the WPR approach to policy analysis.  The research reveals that juvenile delinquency and juvenile justice is currently being politicized in terms of crisis and that such politicization has been historically present, although it did not lead to drastic changes of the penal system. Additionally, it reveals that the problem representations are heavily influenced by the ideology of hegemonic neoliberalism and cultures of control. Altogether, the findings attest to a departure from previous traditions and a shift towards a culture of control.
412

Exteme variables in star forming regions

Contreras Peña, Carlos Eduardo January 2015 (has links)
The notion that low- to intermediate-mass young stellar objects (YSOs) gain mass at a constant rate during the early stages of their evolution appears to be challenged by observations of YSOs suffering sudden increases of the rate at which they gain mass from their circumstellar discs. Also, this idea that stars spend most of their lifetime with a low accretion rate and gain most of their final mass during short-lived episodes of high accretion bursts, helps to solve some long-standing problems in stellar evolution. The original classification of eruptive variables divides them in two separate subclasses known as FU Orionis stars (FUors) and EX Lupi stars (EXors). In this classical view FUors are at an early evolutionary stage and are still gaining mass from their parent envelopes, whilst EXors are thought to be older objects only surrounded by an accretion disc. The problem with this classical view is that it excludes younger protostars which have higher accretion rates but are too deeply embedded in circumstellar matter to be observed at optical wavelengths. Optically invisible protostars have been observed to display large variability in the near-infrared. These and some recent discoveries of new eruptive variables, show characteristics that can be attributed to both of the optically-defined subclasses of eruptive variables. The new objects have been proposed to be part of a new class of eruptive variables. However, a more accepted scenario is that in fact the original classes only represent two extremes of the same phenomena. In this sense eruptive variability could be explained as arising from one physical mechanism, i.e. unsteady accretion, where a variation in the parameters of such mechanism can cause the different characteristics observed in the members of this class. With the aim of studying the incidence of episodic accretion among young stellar objects, and to characterize the nature of these eruptive variables we searched for high amplitude variability in two multi-epoch infrared surveys: the UKIDSS Galactic Plane Survey (GPS) and the Vista Variables in the Via Lactea (VVV). In order to further investigate the nature of the selected variable stars, we use photometric information arising from public surveys at near- to farinfrared wavelengths. In addition we have performed spectroscopic and photometric follow-up for a large subset of the samples arising from GPS and VVV. We analyse the widely separated two-epoch K-band photometry in the 5th, 7th and 8th data releases of the UKIDSS Galactic Plane Survey. We find 71 stars with _K > 1 mag, including 2 previously known OH/IR stars and a Nova. Even though the mid-plane is mostly excluded from the dataset, we find the majority (66%) of our sample to be within known star forming regions (SFRs), with two large concentrations in the Serpens OB2 association (11 stars) and the Cygnus-X complex (27 stars). The analysis of the multi-epoch K-band photometry of 2010-2012 data from VVV covering the Galactic disc at |b| < 1◦ yields 816 high amplitude variables, which include known variables of different classes such as high mass X-ray binaries, Novae and eclipsing binaries among others. Remarkably, 65% of the sample are found concentrated towards areas of star formation, similar to the results from GPS. In both surveys, sources in SFRs show spectral energy distributions (SEDs) that support classification as YSOs. This indicates that YSOs dominate the Galactic population of high amplitude infrared variable stars at low luminosities and therefore likely dominate the total high amplitude population. Spectroscopic follow-up allows us to confirm the pre-main sequence nature of several GPS and VVV Objects. Most objects in both samples show spectroscopic signatures that can be attributed to YSOs undergoing high states of accretion, such as veiling of photospheric features and CO emission, or show FUor-like spectra. We also find a large fraction of objects with 2.12 μm H2 emission that can be explained as arising from shock-excited emission caused by molecular outflows. Whether these molecular outflows are related to outbursts events cannot be confirmed from our data. Adding the GPS and VVV spectroscopic results, we find that between 6 and 14 objects are new additions to the FUor class from their close resemblance to the near-infrared spectra of FUors, and at least 23 more objects are new additions to the eruptive variable class. For most of these we are unable to classify them into any of the original definitions for this variable class. In any case, we are adding up to 37 new stars to the eruptive variable class which would double the current number of known objects. We note that most objects are found to be deeply embedded optically invisible stars, thus increasing the number of objects belonging to this subclass by a much larger factor. In general, objects in our samples which are found to be likely eruptive variable stars show a mixture of characteristics that can be attributed to both of the optically-defined classes. This agrees well with the recent discoveries in the literature. Finally, we are able to derive a first rough estimate on the incidence of episodic accretion among class I YSOs in the star-forming complex G305. We find that _ 9% of such objects are in a state of high accretion. This number is in agreement with previous theoretical and observational estimates among class I YSOs.
413

Internetanvändares möjligheter till undanröjande av personuppgifter : En jämförelse mellan rätten till rättelse enligt 28 § PUL och rätten till radering (”rätten att bli bortglömd”) enligt artikel 17 i den allmänna dataskyddsförordningen. / Internet users possibilities of removal of personal data : A comparison between the right to rectification under 28 § PUL and the right to erasure (”right to be forgotten”) in accordance with the General Data Protection Regulation.

Medelius, Hanna, von Segebaden, Hanna January 2016 (has links)
Tekniken utvecklas ständigt och utvecklingen har bland annat lett till att det idag kan lagras och bearbetas mycket större mängder data än förr, vilket innebär att även behandlingen av personuppgifter är mer omfattande än tidigare. Den tekniska utvecklingen tillsammans med dess nya fenomen och förfaranden ställer krav på en förnyad lagstiftning. Inom EU nåddes under hösten 2015 en överenskommelse om en ny dataskyddslagstiftning vilken har resulterat i en dataskyddsreform innehållande två rättsakter: en förordning och ett direktiv. Förordning- en trädde ikraft den 24 maj 2016 och ska tillämpas från och med den 25 maj 2018. Uppsatsen kommer att behandla huruvida personuppgiftsskyddet vid internetanvändning för enskilda internetanvändare kommer att förändras genom införandet av den nya förordningens artikel 17. Artikeln lagstadgar en rätt till radering (”rätten att bli bortglömd”), och motsva- rande rättigheter finns i gällande rätt i 28 § personuppgiftslagen, i vilken möjligheten till rät- telse stadgas. Syftet med artikeln är att stärka internetanvändarnas kontroll över sina person- uppgifter. Genom införandet av artikel 17 i den allmänna dataskyddsförordningen kommer den enskilde internetanvändarens rätt att få uppgifter undanröjda att tillgängliggöras och förstärkas, genom lägre krav på tillämplighet i jämförelse med 28 § personuppgiftslagen. Möjligheterna till att erhålla fullständig information om vilka personuppgifter som kan påverka internetanvändaren är dessvärre nästintill obefintliga, varför dennes faktiska kontroll inte försäkras genom artikel 17. Trots att den enskilde internetananvändarens kontroll över sina personuppgifter förstärks, kommer syftet med artikel 17 inte nödvändigtvis säkerställas i praktiken genom införandet av den allmänna dataskyddsförordningen.
414

Three essays on the value premium : can investors capture the promised rewards?

Scislaw, Kenneth Edward January 2010 (has links)
A consensus exists in the body of academic literature that stocks with high BE/ME characteristics outperform stocks with low BE/ME characteristics. Researchers disagree, however, as to the cause of the phenomenon. Two competing theories have emerged. The value premium originates either from the relative riskiness of high BE/ME value and low BE/ME growth stocks or from the persistent irrational pricing of those stocks. Market participants question whether the long lineage of academic research showing the existence of the value premium can actually be applied to their portfolio decision-making. The lack of a pervasive value premium across stock size strata suggests the return phenomenon may result from information asymmetry or trading noise, and not from the pricing of greater risk. The value premium appears to be exclusively available to market participants who can effectively navigate the smallest, most illiquid segment of the stock market. In other words, the value premium does not appear to be available to large institutional investors.
415

La binarité des étoiles Ae/Be de Herbig vue par l'optique adaptative et la spectroscopie : une étude du système triple TY CrA

Corporon, Patrice 19 March 1998 (has links) (PDF)
Les étoiles multiples sont nombreuses, tant parmi les objets jeunes de faible masse, les étoiles T Tauri, que parmi les astres de la Séquence Principale (SP). En ce qui concerne les étoiles jeunes de masse intermédiaire, les étoiles Ae/Be de Herbig (HAeBe), le statut de la binarité est peu connu. Nous avons réalisé une recherche systématique de binaires HAeBe en utilisant deux techniques: l'imagerie à haute résolution angulaire avec la méthode de l'Optique Adaptative d'une part, et la spectroscopie visible à haute résolution d'autre part. Ces techniques complémentaires nous ont permis d'identifier plus d'une vingtaine de nouvelles étoiles binaires; la fréquence de binarité déduite est d'au moins 50 %, voir supérieure à cause des biais observationnels discutés dans la thèse. Pour la première fois, les types spectraux des compagnons ont pu être déterminés dans une vingtaine de systèmes visuels. Les implications de nos observations pour la présence de disques de poussières et la détection d'émission X dans les étoiles HAeBe sont présentées. Les contraintes apportées pour les théories de formation des binaires sont discutées. Une partie importante de la thèse est consacrée à une étude approfondie de l'étoile triple TY CrA, l'unique système spectroscopique hiérarchisé parmi les étoiles Ae/Be de Herbig. Après une description complète des paramètres orbitaux et stellaires, la modélisation de la dynamique de cet objet particulier a été réalisée. Nos calculs théoriques montrent que la cohésion du système est assurée par effet de marée à l'oeuvre dans la binaire à éclipse centrale. L'environnement circumstellaire de TY CrA a également été étudié à partir d'observations spectroscopiques infrarouges avec le télescope spatial ISO et à partir d'images en Optique Adaptative dans le proche infrarouge.
416

Formation des raies dans les vents des étoiles Ae/Be de Herbig

Bouret, Jean Claude 13 November 1998 (has links) (PDF)
Les étoiles Ae/Be de Herbig sont des étoiles pré-séquence principale de masse intermédiaire (2-5 M) présentant les signes d'une activité intense et de vents stellaires importants. L'origine de ces phénomènes reste mystérieuse car les mécanismes efficaces dans d'autres parties du diagramme HR sont, ici, inopérants. Nous avons étudié la formation des raies dans les vents de ces étoiles à l'aide d'un modèle semi-empirique à symétrie sphérique, les contraintes sur les paramètres libres du modèle étant alors déduites en comparant les spectres théoriques aux observations. Avec cette méthode, nous avons modélisé les raies de résonance de C IV et Mg II ainsi que les raies de Balmer et les continus de l'hydrogène, pour un échantillon représentatif d'étoiles. Nous avons pu confirmer que ces vents ont la même structure générale, et notamment une chromosphère à température modérée (T ~ 20 000 K). Nous obtenons des taux de perte de masse en très bon accord avec ceux déduits des observations radio. La quantité d'énergie dissipée dans le vent a été estimée par le calcul des pertes radiatives. Les valeurs obtenues sont supérieures à celles proposées par les modèles faisant intervenir des disques d'accrétion ou la rotation interne de l'étoile comme source d'énergie pour expliquer l'activité. La modélisation de la raie 1240 A de N V dans le vent d'AB Aur (prototype des étoiles Ae/Be de Herbig), observée avec le télescope spatial Hubble, nous a conduits à développer une méthode pour simuler la présence de globules chauds (T ~ 10 5 K) créés par des chocs, selon un modèle inspiré du vent solaire. Ce modèle nous permet également d'expliquer l'émission X observée par le satellite ROSAT. Les pertes radiatives occasionnées par ces globules sont supérieures à l'énergie cinétique du vent, ce qui montre que d'autres processus dissipatifs sont à l'oeuvre dans le vent de cette étoile. Ce travail constitue la première étape vers la prise en compte des écarts à la symétrie sphérique, révélés par la modulation rotationnelle de certaines raies du vent d'AB Aur. L'étude de la raie He l D3 a permis de poser les premières contraintes sur la physique à la base du vent d'AB Aur. Pour former une composante en émission décalée vers le bleu conforme aux observations, il est nécessaire de considérer des gradients de vitesse et des taux de perte de masse très élevés. Ce résultat montre que le vent d'AB Aur est fortement hétérogène, y compris dans les régions où il prend naissance. Il apparaît aussi que la composante en émission décalée vers le rouge de cette raie ne peut pas se former dans le vent mais qu'elle est vraisemblablement le résultat d'une accrétion de matière sur les pôles de l'étoile. Ces résultats représentent un ensemble de contraintes fortes, sur lequel il est désormais possible de s'appuyer pour mener à bien une étude théorique des vents des étoiles Ae/Be de Herbig.
417

The Sizes and Depletions of the Dust and Gas Cavities in the Transitional Disk J160421.7-213028

Dong, Ruobing, Marel, Nienke van der, Hashimoto, Jun, Chiang, Eugene, Akiyama, Eiji, Liu, Hauyu Baobab, Muto, Takayuki, Knapp, Gillian R., Tsukagoshi, Takashi, Brown, Joanna, Bruderer, Simon, Koyamatsu, Shin, Kudo, Tomoyuki, Ohashi, Nagayoshi, Rich, Evan, Satoshi, Mayama, Takami, Michihiro, Wisniewski, John, Yang, Yi, Zhu, Zhaohuan, Tamura, Motohide 21 February 2017 (has links)
We report ALMA Cycle 2 observations of 230 GHz (1.3 mm) dust continuum emission, and (CO)-C-12, (CO)-C-13, and (CO)-O-18 J = 2-1 line emission, from the Upper Scorpius transitional disk [PZ99] J160421.7-213028, with an angular resolution of similar to 0''.25 (35 au). Armed with these data and existing H-band scattered light observations, we measure the size and depth of the disk's central cavity, and the sharpness of its outer edge, in three components: sub-mu m-sized "small" dust traced by scattered light, millimeter-sized "big" dust traced by the millimeter continuum, and gas traced by line emission. Both dust populations feature a cavity of radius similar to 70 au that is depleted by factors of at least 1000 relative to the dust density just outside. The millimeter continuum data are well explained by a cavity with a sharp edge. Scattered light observations can be fitted with a cavity in small dust that has either a sharp edge at 60 au, or an edge that transitions smoothly over an annular width of 10 au near 60 au. In gas, the data are consistent with a cavity that is smaller, about 15 au in radius, and whose surface density at 15 au is 10(3 +/- 1) times smaller than the surface density at 70 au; the gas density grades smoothly between these two radii. The CO isotopologue observations rule out a sharp drop in gas surface density at 30 au or a double-drop model, as found by previous modeling. Future observations are needed to assess the nature of these gas and dust cavities (e.g., whether they are opened by multiple as-yet-unseen planets or photoevaporation).
418

COST AND ACCURACY COMPARISONS IN MEDICAL TESTING USING SEQUENTIAL TESTING STRATEGIES

Ahmed, Anwar 14 May 2010 (has links)
The practice of sequential testing is followed by the evaluation of accuracy, but often not by the evaluation of cost. This research described and compared three sequential testing strategies: believe the negative (BN), believe the positive (BP) and believe the extreme (BE), the latter being a less-examined strategy. All three strategies were used to combine results of two medical tests to diagnose a disease or medical condition. Descriptions of these strategies were provided in terms of accuracy (using the maximum receiver operating curve or MROC) and cost of testing (defined as the proportion of subjects who need 2 tests to diagnose disease), with the goal to minimize the number of tests needed for each subject while maintaining test accuracy. It was shown that the cost of the test sequence could be reduced without sacrificing accuracy beyond an acceptable range by setting an acceptable tolerance (q) on maximum test sensitivity. This research introduced a newly-developed ROC curve reflecting this reduced sensitivity and cost of testing called the Minimum Cost Maximum Receiver Operating Characteristic (MCMROC) curve. Within these strategies, four different parameters that could influence the performance of the combined tests were examined: the area under the curve (AUC) of each individual test, the ratio of standard deviations (b) from assumed underlying disease and non-disease populations, correlation (rho) between underlying disease populations, and disease prevalence. The following patterns were noted: Under all parameter settings, the MROC curve of the BE strategy never performed worse than the BN and BP strategies, and it most frequently had the lowest cost. The parameters tended to have less of an effect on the MROC and MCMROC curves than they had on the cost curves, which were affected greatly. The AUC values and the ratio of standard deviations both had a greater effect on cost curves, MROC curves, and MCMROC curves than prevalence and correlation. The use of BMI and plasma glucose concentration to diagnose diabetes in Pima Indians was presented as an example of a real-world application of these strategies. It was found that the BN and BE strategies were the most consistently accurate and least expensive choice.
419

Le désir érotique dans l’œuvre d’Alexandre Papadiamantis / The Erotic desire in the the Work of Alexandros Papadiamantis

Evzonas, Nicolas 14 January 2012 (has links)
Perçu pendant fort longtemps comme un saint anaphrodite et « castré » avant d’être reconnu comme l’écrivain le plus sensuel des Lettres grecques modernes, Alexandre Papadiamantis (1851-1911), auteur prolifique de près de cent quatre-vingt nouvelles et de trois romans et trésor national hellène, est un artiste antinomique qui ne cesse d’intriguer la critique et de susciter des débats contradictoires. Le présent travail propose une lecture de son œuvre complète axée sur un sujet controversé dont aucune étude systématique n’a été entreprise, malgré un siècle de surabondante critique littéraire : le désir érotique, que nous entendons essentiellement comme le rapport à un objet de convoitise explicitement ou implicitement désigné comme tel, humain ou inhumain, vivant ou inanimé, suscitant un certain nombre de réactions physiques et/ou psychiques et sollicitant un réseau complexe de sens, de sensations, de méditations, d’excitations et de significations représentées par le biais des mots. Une telle définition emphatise l’imbrication de la pulsion et du langage et distingue le désir de l’amour, ce dernier constituant plutôt une stase du désir, un arrêt et une fixation sur l’« autre ». Notre objectif est de comprendre comment l’érotisme ainsi défini s’exprime dans les textes, quels en sont les enjeux psychologiques, les interconnexions avec les techniques narratives, les choix stylistiques et les particularités linguistiques et quelles transformations littéraires il subit dans l’œuvre, en somme, quels sont sa destinée mythique, son aboutissement idéologique et son apothéose thématique, en somme son issue dans l’écriture. / Viewed for ages as an anaphrodite and « castrated » saint before being recognized as the most sensual writer in modern Greek literature, Alexandros Papadiamantis (1851-1911), prolific author of approximately one hundred and eighty short stories, and three historical novels, and deemed to be a Hellenic national treasure, is an antinomic artist who keeps intriguing critics and arousing open debates. The present thesis offers a reading of his complete work based on a controversial subject of which no systematic study has been undertaken before, despite a century of numerous literary comments : erotic desire, defined as the connexion with an objet of lust explicitely or implicitely defined as such, human or inhuman, alive or inanimated, and which rises a number of physical and/or psychological reactions, a complex network of meanings, sensations, meditations, actions and fantasies represented through words. This definition emphasizes the interweaving of drive and language and discerns between desire and love, the latter being rather a stasis of desire, and a fixation on the « other ». Our goal is to understand how eroticism thus defined is expressed throughout the texts, to point out the psychological issues associated with it, its interconnections with the narrative techniques, stylistic choices and linguistic particularities and the literary transformations it undergoes throughout the Papadiamantian opus, that is to say its mythic destiny, its ideological culmination and its thematic apotheosis, in short its outcome in writing.
420

What is the Mass of a Gap-opening Planet?

Dong, Ruobing, Fung, Jeffrey 24 January 2017 (has links)
High-contrast imaging instruments such as GPI and SPHERE are discovering gap structures in protoplanetary disks at an ever faster pace. Some of these gaps may be opened by planets forming in the disks. In order to constrain planet formation models using disk observations, it is crucial to find a robust way to quantitatively back out the properties of the gap-opening planets, in particular their masses, from the observed gap properties, such as their depths and widths. Combining 2D and 3D hydrodynamics simulations with 3D radiative transfer simulations, we investigate the morphology of planet-opened gaps in near-infrared scattered-light images. Quantitatively, we obtain correlations that directly link intrinsic gap depths and widths in the gas surface density to observed depths and widths in images of disks at modest inclinations under finite angular resolution. Subsequently, the properties of the surface density gaps enable us to derive the disk scale height at the location of the gap h, and to constrain the quantity M-p(2)/alpha, where Mp is the mass of the gap-opening planet and a characterizes the viscosity in the gap. As examples, we examine the gaps recently imaged by VLT/SPHERE, Gemini/GPI, and Subaru/HiCIAO in HD 97048, TW Hya, HD 169142, LkCa. 15, and RX J1615.3-3255. Scale heights of the disks and possible masses of the gap-opening planets are derived assuming each gap is opened by a single planet. Assuming a = 10(-3), the derived planet masses in all cases are roughly between 0.1 and 1M(J).

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