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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.
341

Le critère organique en droit administratif français / The organic criterion in French administrative law

Murgue-Varoclier, Paul-Maxence 28 November 2017 (has links)
Le critère organique en droit administratif est un instrument de qualification juridique qui repose sur la présence d’une personne publique dans un rapport de droit. Il trouve ses origines à la fin du XIXème siècle dans la subjectivisation des droits de puissance publique dont l’Etat est investi et l’admission de la distinction entre les personnes publiques et les personnes privées. Confondu avec le critère du service public au début du XXème siècle, le critère organique acquiert son autonomie à l’heure de la « crise » de la notion juridique de service public dans les années 1930-1940. Le critère organique, qui témoigne de la logique institutionnelle à laquelle le droit administratif français est attaché, sert de support à la construction des notions-cadres de ce droit.Depuis de nombreuses années, le critère organique fait cependant l’objet d’une vive contestation. D’une part, le mouvement de « banalisation » qui traverse le droit des personnes publiques renforce l’insuffisance de ce critère dans la détermination du droit applicable. D’autre part, les transformations contemporaines du modèle administratif français provoquent une régression de la référence à ce critère. Alors que la personnalité publique apparaissait hier comme le mode privilégié de prise en charge de l’action publique, l’administration est incitée à externaliser ses activités. En dépit d’un phénomène de « privatisation » de l’action administrative, le juge et le législateur maintiennent l’application de règles exorbitantes en l’absence du critère organique.Alors que le phénomène administratif se déploie aujourd’hui au-delà des seules personnes de droit public, la définition du critère organique en droit administratif demeure fermement arrimée à la notion de personne publique. Plusieurs facteurs invitent toutefois à reconsidérer la définition de ce critère. La fonctionnalisation de l’action publique ne dissimule qu’imparfaitement les liens qui s’établissent au sein de la « sphère publique » entre les personnes publiques et certaines personnes privées, qui demeurent sous étroit contrôle public. C’est donc sur la base de la notion de « contrôle public » que peut être entreprise une redéfinition de ce critère en droit administratif. / In French administrative law, the organic criterion is an instrument of legal qualification dependent upon the presence of a public body in a legal relationship. Its origins date back to the 19th century in the subjectivation of the rights of public power of which the State is invested and the differentiation of the public and private bodies. Misconstrued with the criterion of public service at the beginning of the 20th century, the organic criterion gains its autonomy at the time of the "crisis" of the notion of public service which consecrates the dissociation of notions of public body and public service. This criterion, which bears witness to the institutional logic to which administrative law is associated, serves as the foundation for the construction of notions.However, the organic criterion has been the subject of strong opposition for many years. On the one hand, the "trivialization" movement which affects rights of public bodies reinforces the inadequacy of this criterion in determining the applicable law. On the other, as a result of contemporary changes to the French administrative model, the reference to this criterion has diminished. While the public body appeared in the past as the preferred mode for public action, the administration is encouraged nowadays to "outsource" its activities. Despite a phenomenon of "privatization" of administrative measures, the judge and the legislator maintain the application of special rules in absence of the organic criterion.While the administrative phenomenon now extends beyond public law, the definition of the organic criterion in administrative law remains firmly linked to the notion of public body. Several factors, however, call for a redefinition of this criterion. The functionalization of public action only partially conceals the relation between public and certain private bodies within the public sphere which nevertheless remain under close public control. It is on the basis of the notion of "public control" that a redefinition of this criterion can be undertaken in administrative law.
342

Longitudinal handling characteristics of a tailless gull-wing aircraft

Agenbag, Daniel Sarel 18 September 2008 (has links)
A handling quality investigation was performed on the swept gull-wing configuration. The swept gull-wing configuration is tailless and has a wing with a transition in the sweep and dihedral angle. An example of this type of aircraft is the Exulans. This aircraft is currently under development at the University of Pretoria. The handling quality study was focussed on pitch axis dynamics. The Exulans is a research testbed that will be used to investigate the swept gull-wing configuration and its special controls by means of full-scale flight testing. Variable wing sweep, twisting elevons and winglets will be investigated as means of control. These control devices are configured in such a way as to have minimum impact on the performance of the aircraft. The handling qualities of the swept gull-wing configuration have to be acceptable while using these different control strategies. The study was launched to investigate whether a gull-wing configuration aircraft will have satisfactory handling qualities at CG positions associated with the most favourable aerodynamic performance. There is an aerodynamic performance gain in designing an aircraft so that the CG falls on the so-called `E-point'. The E-point is the centre of pressure for an elliptical circulation distribution. An elliptical circulation distribution is associated with the highest Oswald efficiency for an aircraft. Time domain simulation techniques and frequency domain analysis techniques were used to analyse the handling qualities of the gull-wing configuration. The C-star criterion was used to analyse handling qualities with time domain simulation data as input. Comparative time domain simulations were performed between the Exulans and other aircraft to compare handling qualities. Eigenvalue analysis was used together with the thumbprint criterion to investigate inherent gull-wing airframe dynamics. The Shomber-Gertsen and Military Specification 8785 criteria were also used for the same purpose. The Neal-Smith method was used to investigate the effect of control authority on handling qualities and the effect of a pilot. The Monnich and Dalldorff criterion was used to evaluate gust handling qualities. An analysis chart by Fremaux and Vairo was used to evaluate the tumbling susceptibility of the gull-wing configuration. The pitch handling quality investigation shows sufficient promise that the swept gull-wing configuration will have acceptable handling qualities with the CG placed at positions associated with optimised aerodynamic performance. Analysis showed that the swept gull-wing configuration is potentially prone to tumbling. With low static margins, the configuration should exhibit improved handling qualities in gusty conditions when compared to existing tailless aircraft. It is recommended that a lateral handling quality study be performed before full scale flight testing commences on the Exulans. In addition, the possibility of wingtip stall must be investigated for the case of the swept gull-wing configuration. / Dissertation (MEng)--University of Pretoria, 2008. / Mechanical and Aeronautical Engineering / unrestricted
343

From doctrine to practice: responsibility to protect and military intervention in Libya 2011

Tahir, Bushra 15 March 2016 (has links)
The intervention in Libya is the best example to date to judge the implementation of the Responsibility to Protect. In 2011, public demonstrations started in Libya seeking political and economic reforms in the country. In return, the Libyan President Maummar Al-Qaddafi threatened mass atrocities in Libya. This allowed the UNSC to sanction the use of force against Qaddafi’s regime in order to protect civilians. First, under resolution 1970 (2011), the UNSC referred the case to the International Criminal Court and applied sanctions. Second, via resolution 1973 (2011), the application of force was approved for the express purpose of “protecting civilians.” This thesis assess whether the military intervention in Libya in 2011 was R2P case. This question is answered by an analysis based upon the UNSC’s Resolutions, Council’s proceedings, and other official documents. / May 2016
344

The validation of a performance-based assessment battery

Wilson, Irene Rose 11 1900 (has links)
Legislative pressures are being brought to bear on South African employers to demonstrate that occupational assessment is scientifically valid and culture-fair. The development of valid and reliable performance-based assessment tools will enable employers to meet these requirements. The general aim of this research was to validate a performance-based assessment battery for the placement of sales representatives. A literature survey examined alternative assessment measures and methods of performance measurement, leading to the conclusion that the combination of the work sample as a predictor measure and the managerial rating of performance as a criterion measure offer a practical and cost-effective assessment process to the sales manager. The empirical study involved 54 sales persons working for the Commercial division of an oil marketing company, selling products and services to the commercial and industrial market. By means of the empirical study, a significant correlation was found between performance of sales representatives in terms of the performance-based assessment battery for the entry level of the career ladder and their behaviour in the field as measured by the managerial performance rating instrument. The limitations of the sample, however, prevent the results from being generalised to other organisations. / Industrial & Organisational Psychology / M.A. (Industrial Psychology)
345

Modelling of driven free surface liquid films

Galvagno, Mariano January 2015 (has links)
In several types of coating processes a solid substrate is removed at a controlled velocity U from a liquid bath. The shape of the liquid meniscus and the thickness of the coating layer depend on U. These dependencies have to be understood in detail for non-volatile liquids to control the deposition of such a liquid and to lay the basis for the control in more complicated cases (volatile pure liquid, solution with volatile solvent). We study the case of non-volatile liquids employing a precursor film model that describes partial wettability with a Derjaguin (or disjoining) pressure. In particular, we focus on the relation of the deposition of (i) an ultrathin precursor film at small velocities and (ii) a macroscopic film of thickness h ∝ U^(2/3) (corresponding to the classical Landau Levich film). Depending on the plate inclination, four regimes are found for the change from case (i) to (ii). The different regimes and the transitions between them are analysed employing numerical continuation of steady states and saddle-node bifurcations and simulations in time. We discuss the relation of our results to results obtained with a slip model. In connection with evaporative processes, we will study the pinning of a droplet due to a sharp corner. The approach employs an evolution equation for the height profile of an evaporating thin film (small contact angle droplet) on a substrate with a rounded edge, and enables one to predict the dependence of the apparent contact angle on the position of the contact line. The calculations confirm experimental observations, namely that there exists a dynamically produced critical angle for depinning that increases with the evaporation rate. This suggests that one may introduce a simple modification of the Gibbs criterion for pinning that accounts for the non-equilibrium effect of evaporation.
346

Dimensioning of Punctiform Metal-Composite Joints: A Section-Force Related Failure Criterion

Seidlitz, Holger, Ulke-Winter, Lars, Gerstenberger, Colin, Kroll, Lothar 20 April 2015 (has links) (PDF)
Reliable line production processes and simulation tools play a central role for the structural integration of thermoplastic composites in advanced lightweight constructions. Provided that material- adapted joining technologies are available, they can be applied in heavy-duty multi-material designs (MMD). A load-adapted approach was implemented into the new fully automatic and faulttolerant thermo mechanical flow drill joining (FDJ) concept. With this method it is possible to manufacture reproducible high strength FRP/metal-joints within short cycle times and without use of extra joining elements for the first time. The analysis of FDJ joints requires a simplified model of the joint to enable efficient numerical simulations. The present work introduces a strategy in modeling a finite-element based analogous-approach for FDJ-joints with glass fiber reinforced polypropylene and high-strength steel. Combined with a newly developed section-force related failure criterion, it is possible to predict the fundamental failure behavior in multi-axial stress states. The functionality of the holistic approach is illustrated by a demonstrator that represents a part of a car body-in-white structure. The comparison of simulated and experimentally determined failure loads proves the applicability for several combined load cases.
347

Persons : their identity and individuation

Melin, Roger January 1998 (has links)
This study is about the nature of persons and personal identity. It belongs to a tradition that maintains that in order to understand what it is to be a person we must clarify what personal identity consists in. In this pursuit, I differentiate between the problems (i) How do persons persist? and (ii) What facts, if any, does personal identity consist in? Concerning the first question, I argue that persons persist three-dimensionally (the endurance view), and not four-dimensionally (the perdurarne view), on the ground that objects must always fall under some substance sortal concept S (the sortal dependency of individuation), and that the concept person entails that objects falling under it are three-dimensional. Concerning the second question, I differentiate between Criterianists, who maintain that it is possible to specify a non-circular and informative criterion for personal identity, and Non-Criterianists, who deny that such a specification is possible. I argue against Criterianist accounts of personal identity on the ground that they are either (i) circular, (ii) violate the intrinsicality of identity or (iii) do not adequately represent what we are essentially. I further criticise three Psychological Non-Criterianist accounts of personal identity on the ground that they wrongly assume that 'person' refers to mental entities. Instead I formulate the Revised Animal Attribute View where person is understood as a basic sortal concept which picks out a biological sort of enduring animals. In this, I claim that the real essence of a person is determined by the real essence of the kind of animal he is, without thereby denying that persons have a real essence as persons. / digitalisering@umu
348

A Criterion-Referenced Analysis of Form F of the Standardized Bible Content Tests of the American Association of Bible Colleges

Gaede, Charles S. (Charles Samuel) 12 1900 (has links)
The purposes of this study were to: (a) analyze subjects' responses from Form F of the Standardized Bible Content Tests of the American Association of Bible Colleges by factor analysis and the Rasch measurement model and (b) determine dimensionality of Form F, determine the correlation to the Literal, Anti-literal, Mythological Scales, and determine the best criterion-referenced test design of Form F using Rasch measurement procedures. Volunteers from a purposefully selected sample of nine colleges from the American Association of Bible Colleges participated in the study. One research instrument with five demographic questions, the Standardized Bible Content Test Form F, and the Literal, Anti-literal, and Mythological Scales was administered to 179 volunteer graduating seniors. Frequencies and percentages of responses were computed for the demographic questions. Mean scores on the Literal, Anti-literal, and Mythological Scales were computed for gender and religious affiliation. Principal components analysis of Form F with varimax rotation and list-wise deletion of missing data was used to assess the dimensionality of Form F. Correlations between scores on the Literal, Anti-literal and Mythological Scales and scores from the principal components analysis of Form F were computed. Dunn's multiple comparison procedures were used to test for statistical significance. Rasch-Model measurement analysis of the scales extracted by principal components analysis was accomplished to obtain suggested target description, test design, variable definition, and item calibration.
349

Étude du comportement en post-flambement d’un panneau de fuselage composite infusé avec structures intégrées / Study of the post-buckling behaviour of a composite fuselage panel infused with integrated structures

Perret, Adrien 28 June 2011 (has links)
Ces travaux concernent l’étude numérique et expérimentale d’un panneau composite autoraidi fabriqué par le procédé d’infusion de résine (Liquid Resin Infusion LRI). Le procédé LRI permet d’intégrer des structures sur les peaux d’un panneau représentatif d’un fuselage composite. Dans l’étude numérique, des modèles éléments finis sont réalisés, pour étudier le comportement global du panneau en post-flambement. Cela permet de mettre au point un dispositif d’essai. L’approche expérimentale consiste en l’application de différentes méthodes pour contrôler la pièce et réaliser l’essai. Des essais de caractérisation sont aussi réalisés pour obtenir les propriétés mécaniques nécessaires à l’élaboration de modèles numériques locaux, permettant de décrire la décohésion des structures intégrées. / These works are related to the numerical and experimental study of a composite stiffened panel, which is manufactured by a resin infusion process (Liquid Resin Infusion LRI). This manufacturing process allows structures to be integrated onto the skins of a panel being representative of a composite fuselage. Finite element models are built along with the numerical study, in order to deal with the post-buckling global behaviour of this panel. This leads to perfect a test set-up addressed during the experimental investigation. Several experimental methods are used to check the test panel and achieve the test. Material properties are also determined through material testing intended for the development of local numerical models, describing the integrated structures decohesion.
350

Modélisation explicite de l’écaillage sous incendie du béton : approche thermo-hydro-mécanique avec des conditions aux limites évolutives / Explicit modeling of fire induced spalling of concrete : a thermo-hydro-mechanical approach with evolving boundary conditions

Phan, Minh Tuyen 07 November 2012 (has links)
Dans les dernières années, les incendies majeurs dans les tunnels ont causé des dommages importants. Dans ces conditions extrêmes (la température dépasse rapidement 1200 °C), l'augmentation de pression dans les pores, la dilatation thermique empêchée, l'incompatibilité de dilatation thermique entre la pâte du ciment et des granulats, la déshydratation ... sont des principaux mécanismes de dégradation qui peuvent être à l'origine de l'écaillage. L'écaillage progressif pendant l'incendie se manifeste par le détachement de la surface du béton par petits morceaux réduisant ainsi la section résistante et pouvant conduire à une rupture prématurée de la structure. Dans cette thèse, un modèle éléments finis THM est enrichi par un modèle d'écaillage progressif en proposant un critère d'écaillage de type détachement-flambement. La partie thermo-hydrique du modèle THM est basée sur l'approche à trois fluides en milieux partiellement saturés. Le comportement mécanique est développé dans le cadre d'une approche thermo-poro-mécanique couplée à l'endommagement et à la plasticité adoucissante. Cette modélisation de l'écaillage conduit à un problème avec frontière et conditions aux limites évolutives. Une stratégie de résolution numérique sans remaillage a été développée pour transférer les conditions aux limites THM simultanément avec l'occurrence de l'écaillage. L'implémentation du modèle dans le code aux éléments finis CESAR-LCPC a permis de procéder à différentes études paramétriques et à des confrontations avec des essais pour évaluer les capacités opérationnelles du modèle à décrire l'occurrence de l'écaillage et identifier les paramètres majeurs qui la contrôlent / In the recent years, there were major tunnels fires which caused fatalities and severe traffic restrictions. In such extreme conditions (temperatures exceeding 1200 °C for considerable time spans), pore pressure build-up, restrained thermal dilatation, cement paste to aggregate incompatibility, dehydration... are some main degradation mechanisms of concrete that may cause its thermal spalling. Progressive concrete spalling occurring during a fire presents as the breakdown of surface layers which flake into small pebble-like pieces. Then, the resistant section of the structure reduces which may lead to its premature failure.In this thesis, a THM finite element model is enriched with a detachment-buckling type criterion for progressive spalling. The thermo-hygral part of the THM model is based on the three fluid approach for partially saturated porous media. The mechanical part is derived within the framework of thermo-poro-mechanics coupled to damage and softening plasticity.The adopted modeling of spalling leads to a problem with evolving boundary and boundary conditions. A suitable numerical solution strategy without remeshing is then developed in order to transfer properly the THM boundary conditions simultaneously with spalling occurrence.The efficiency of the model THM-Spalling is illustrated by some numerical examples and by parametric studies. These studies identify the influence, on spalling, of size variation of spalling flakes, the average spalling velocity and uncertainties on different material parameters. Confrontation with experimental tests shows satisfactory capacity of the THM-Spalling model in reproducing qualitatively the occurrence of spalling

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