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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.
81

La théorie du Fluxus chez Albert le Grand : principes philosophiques et applications théologiques : le De fluxu causatorum a causa prima et causarum ordine : introduction, texte, traduction, notes et commentaire / The theory of fluxus in Albert the Great's work : philosophical principales and theological implementation : the de fluxu causatorum a causa prima et causarum ordine : introduction, text, translation, notes and commentary

Milazzo, Sébastien 22 November 2007 (has links)
L'objet de cette étude concerne un langage de la procession et de la création trop longtemps oublié dans le contexte de la réception du néoplatonisme et de l’aristotélisme au XIIIe siècle : celui de fluxus, ou écoulement, chez Albert le Grand (1200-1280). Nous proposons ici la situation descriptive, historique et philosophique du texte dans lequel le Doctor universalis expose sa théorie du fluxus : le De fluxu causatorum a causa prima et causarum ordine, quatrième traité du De causis et processu universitatis a prima causa (1264-1267). La doxographie albertinienne, loin d'être une succession de digressiones ou encore de simples paraphrases des opiniones antiquorum, apparaît comme la formation d'une véritable conscience de l'histoire de la philosophie, de sa continuité et des ses ruptures. Plus encore, la doxographie albertinienne a pour fonction de répondre à des problématiques issues non seulement du passé mais aussi du monde contemporain de notre Doctor universalis : car, en effet, à travers la critique du panthéisme d'Hermès Trismégiste ou encore du matérialisme d'Ibn Gebirol, c’est bien l’horizon d’une critique du panthéisme matérialiste de David de Dinant et du panthéisme formaliste d'un Amaury de Bène qui se profile. Nous proposons, en outre, une traduction de travail de ce texte ainsi que son commentaire philosophique linéaire. Albert définit le fluxus comme emanatio et comme processio. Le flux pose la question de la relation du Premier Principe avec les réalités qu'il crée. Comment Albert réussira-t-il à résoudre l’articulation d’une théorie panthéiste et crypto-néoplatonicienne de la procession à une théorie monothéiste et chrétienne de la procession ? / The purpose of this study consists in the language of procession and creation that has fallen into oblivion for too long within the contextual framework of Neo-Platonism and XIII th century Aristotelian understanding : that of the fluxus theory – namely that of the flux one, in Albert the Great’s works ( 1200- 1280). Our ain is to provide the reader with a descriptive , historical and philosophical outlook over the text in which the "Doctor universalis" exposes his flux theory: the “De fluxu causatorum a causa prima et causarum ordine”, the fourth treaty of the "De causis et processu universitatis a prima causa" ( 1264- 1267).Albert's doxography, far from being a series of digressions or still mere paraphrases of "opiniones antiquorum", is to be regarded as the setting up of a genuine awareness process in the history of philosophy, of its never-ending existence and its critical moments. What's more still, the overall purpose of Albert’s doxography is to provide answers to problematic issues non only originating from the past but also rooted in the contemporary world of our "Doctor universalis". Indeed, throughout the criticism of Trismegist’s pantheism or even more clearly, that of Gebirol's materialism, what rises into view is the criticism of Amaury de Bène's formalist pantheism. Besides, the reader is to find a workshop translation of the text as well as its linear-related philosophical commentary. Albert used to define the "fluxus" as an emanation and as a procession. How was Albert, however philosophical-oriented he might have been, to succeed in tackling the argumentation of a Crypto-Neo- Platonism theory of procession and inserting it into a Christian one?
82

Methods of neutron flux determination by means of organic scintillator in neutron-gamma ray mixed field.

January 1987 (has links)
by Chan Chi-Ming. / Chinese title in romanization: Zai zhong zi-r she xian hun he chang zhong, yong you ji shan yue ti ce liang zhong zi tong liang di fang fa. / Thesis (M.Ph.)--Chinese University of Hong Kong, 1987. / Bibliography: leaves 142-149.
83

Some experiments in neutron dosimetry.

January 1976 (has links)
by Hong Kuen Wong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1976. / Includes bibliographical references (leaves 112-121).
84

Contribution à l'étude de déformation et de rupture des roches par une approche discrète / Contribution to the study of deformation and rupture of rocks by a discrete approach

Zhang, Yulong 18 September 2018 (has links)
Dans ce travail, un nouveau modèle de liaison avec critère de rupture de cisaillement non linéaire est d'abord proposé et mis en œuvre dans PFC pour décrire le comportement mécanique de matériaux granulaires cohésifs isotropes tels que le grès. Un grand nombre de tests de compression ont été effectués sur des échantillons 3D. Les résultats montrent que l'effet de la pression de confinement sur la résistance à la compression et le modèle de rupture est bien décrit par ce modèle de liaison. Les effets du chemin de chargement et de la contrainte principale intermédiaire sur la déformation et la rupture ont également été étudiés. Après avoir étendu les paramètres d'élasticité et de résistance, deux modèles de liaison sont couplés pour caractériser l'anisotropie de la résistance et de la déformation dans les matériaux cohésifs anisotropes tels que les roches sédimentaires. Une série de test de compression avec différents chemin de chargement ont été effectués et les résultats numériques sont en bon accord avec les données expérimentales, en particulier pour les propriétés de réponse élastique et de résistance. La transformation du mode de défaillance entre la couche de faiblesse et la matrice de roche sous différentes pressions de confinement a été bien décrite. De plus, le modèle de liaison proposé a été étendu pour étudier le processus de fracturation hydraulique dans les matériaux cohésifs. Un processus de propagation de fracture hydraulique représentatif a été présenté. Enfin, nous avons développé une méthode de reconstruction dimensionnelle de l'irrégularité de la forme des blocs et étudié ses effets sur les impacts des blocs en utilisant une approche basée sur l'énergie. / In this work, a new bond model with nonlinear shear failure criterion is first proposed and implemented in PFC for describing mechanical behavior of isotropic cohesive granular materials such as sandstone. A large number of compression tests have been performed on 3D samples. The results show that the effect of confining pressure on compressive strength and failure pattern is well described by the proposed bond model. Effects of loading path and the intermediate principal stress on deformation and failure have been also investigated. After further extending parameters on elastic and strength, two bond models: the proposed bond model and the improved smooth joint model, are coupled to character the anisotropy of strength and deformation in anisotropic cohesive materials such as sedimentary rocks. A series of conventional triaxial compression tests with different loading paths have been performed and numerical results are in good agreement with experimental data, especially for elastic response and strength properties. The failure mode transformation between weakness layer and rock matrix under different confining pressures has been well described. Furthermore, the proposed bond model has been extended to study hydraulic fracturing process in cohesive materials. A representative hydraulic fracture propagation process has been presented. Influences of different factors, such as confining pressure, fluid viscosity and fluid injection rate, on hydraulic fracture extension have been investigated. Finally, we have developed a dimensional reconstruction method of block shape irregularity and studied its effects on block impacts using an energy based approach.
85

Dissolution rate and diffusivity of lime in steelmaking slag and development of fluoride-free fluxes

Haji Amini, Shahriar, School of Chemical Engineering & Industrial Chemistry, UNSW January 2005 (has links)
A rotating disk technique was used to determine the dissolution rate and diffusivity of CaO and MgO in slags. The dissolution rate was deduced from the measured changes in concentration of oxides in slag with respect to reaction time. The experimental set- up was initially tested with dissolution of magnesia in the CaO ??? 55 wt% Al2O3 slag at 1430 ??C and a measured rate of 2.7 ??10 -5 g/cm2.s was obtained. The dissolution rate was increased by slag chemistry and ranged from 6.5??10-5 to 2.1??10-4 g/cm2.s. The dissolution rate of CaO was measured in CaO ??? 42 wt% Al2O3 ??? 8% SiO2 based slag. The measured dissolution rates were found to be strongly dependent on the slag chemistry and temperature and ranged from 5.03??10 -5 to 3.3??10 -4 g/cm2.s. The dissolution rates were strongly dependent on the rotation speed and results indicate mass transfer in the slag phase to be rate- limiting step. The diffusivity of MgO / CaO was calculated from the dissolution rate and solubility data, using known mass transfer correlations. The diffusivity of MgO in the calcium aluminate slag at 1430 ??C was found to be about 1.1??10-5 cm2/s. Additions of 5 and 10 wt% Fe2O3 increased the diffusivity by a factor ~ 1.5 to 3, respectively. However, with introduction of (CaF2 5 wt% + Fe2O3 5 wt%) and (CaF2 5 wt% + Fe2O3 10 wt%) in the slag, the diffusivity increased considerably by a factor of about 29 and 11, respectively. The diffusivity of CaO in calcium aluminosilicate was measured to be in the order of 10-6 to 10-5 over a temperature range of 1430 ??? 1600 ??C. CaF2 increased the diffusivity by a factor of 3 to 5 while MnOx and FeOx, ilmenite and TiO 2 increased the diffusivity substantially and SiO2 had an opposite effect. The measured diffusivities are in accord with published data on comparable systems and are discussed with reference to Eyring theory. It was concluded that MnOx, FeOx and ilmenite in the slag increase the dissolution rate and diffusivity of lime, showing comparable results with respect to CaF2.
86

Dissolution rate and diffusivity of lime in steelmaking slag and development of fluoride-free fluxes

Haji Amini, Shahriar, School of Chemical Engineering & Industrial Chemistry, UNSW January 2005 (has links)
A rotating disk technique was used to determine the dissolution rate and diffusivity of CaO and MgO in slags. The dissolution rate was deduced from the measured changes in concentration of oxides in slag with respect to reaction time. The experimental set- up was initially tested with dissolution of magnesia in the CaO ??? 55 wt% Al2O3 slag at 1430 ??C and a measured rate of 2.7 ??10 -5 g/cm2.s was obtained. The dissolution rate was increased by slag chemistry and ranged from 6.5??10-5 to 2.1??10-4 g/cm2.s. The dissolution rate of CaO was measured in CaO ??? 42 wt% Al2O3 ??? 8% SiO2 based slag. The measured dissolution rates were found to be strongly dependent on the slag chemistry and temperature and ranged from 5.03??10 -5 to 3.3??10 -4 g/cm2.s. The dissolution rates were strongly dependent on the rotation speed and results indicate mass transfer in the slag phase to be rate- limiting step. The diffusivity of MgO / CaO was calculated from the dissolution rate and solubility data, using known mass transfer correlations. The diffusivity of MgO in the calcium aluminate slag at 1430 ??C was found to be about 1.1??10-5 cm2/s. Additions of 5 and 10 wt% Fe2O3 increased the diffusivity by a factor ~ 1.5 to 3, respectively. However, with introduction of (CaF2 5 wt% + Fe2O3 5 wt%) and (CaF2 5 wt% + Fe2O3 10 wt%) in the slag, the diffusivity increased considerably by a factor of about 29 and 11, respectively. The diffusivity of CaO in calcium aluminosilicate was measured to be in the order of 10-6 to 10-5 over a temperature range of 1430 ??? 1600 ??C. CaF2 increased the diffusivity by a factor of 3 to 5 while MnOx and FeOx, ilmenite and TiO 2 increased the diffusivity substantially and SiO2 had an opposite effect. The measured diffusivities are in accord with published data on comparable systems and are discussed with reference to Eyring theory. It was concluded that MnOx, FeOx and ilmenite in the slag increase the dissolution rate and diffusivity of lime, showing comparable results with respect to CaF2.
87

Dissolution rate and diffusivity of lime in steelmaking slag and development of fluoride-free fluxes

Haji Amini, Shahriar, School of Chemical Engineering & Industrial Chemistry, UNSW January 2005 (has links)
A rotating disk technique was used to determine the dissolution rate and diffusivity of CaO and MgO in slags. The dissolution rate was deduced from the measured changes in concentration of oxides in slag with respect to reaction time. The experimental set- up was initially tested with dissolution of magnesia in the CaO ??? 55 wt% Al2O3 slag at 1430 ??C and a measured rate of 2.7 ??10 -5 g/cm2.s was obtained. The dissolution rate was increased by slag chemistry and ranged from 6.5??10-5 to 2.1??10-4 g/cm2.s. The dissolution rate of CaO was measured in CaO ??? 42 wt% Al2O3 ??? 8% SiO2 based slag. The measured dissolution rates were found to be strongly dependent on the slag chemistry and temperature and ranged from 5.03??10 -5 to 3.3??10 -4 g/cm2.s. The dissolution rates were strongly dependent on the rotation speed and results indicate mass transfer in the slag phase to be rate- limiting step. The diffusivity of MgO / CaO was calculated from the dissolution rate and solubility data, using known mass transfer correlations. The diffusivity of MgO in the calcium aluminate slag at 1430 ??C was found to be about 1.1??10-5 cm2/s. Additions of 5 and 10 wt% Fe2O3 increased the diffusivity by a factor ~ 1.5 to 3, respectively. However, with introduction of (CaF2 5 wt% + Fe2O3 5 wt%) and (CaF2 5 wt% + Fe2O3 10 wt%) in the slag, the diffusivity increased considerably by a factor of about 29 and 11, respectively. The diffusivity of CaO in calcium aluminosilicate was measured to be in the order of 10-6 to 10-5 over a temperature range of 1430 ??? 1600 ??C. CaF2 increased the diffusivity by a factor of 3 to 5 while MnOx and FeOx, ilmenite and TiO 2 increased the diffusivity substantially and SiO2 had an opposite effect. The measured diffusivities are in accord with published data on comparable systems and are discussed with reference to Eyring theory. It was concluded that MnOx, FeOx and ilmenite in the slag increase the dissolution rate and diffusivity of lime, showing comparable results with respect to CaF2.
88

Dissolution rate and diffusivity of lime in steelmaking slag and development of fluoride-free fluxes

Haji Amini, Shahriar, School of Chemical Engineering & Industrial Chemistry, UNSW January 2005 (has links)
A rotating disk technique was used to determine the dissolution rate and diffusivity of CaO and MgO in slags. The dissolution rate was deduced from the measured changes in concentration of oxides in slag with respect to reaction time. The experimental set- up was initially tested with dissolution of magnesia in the CaO ??? 55 wt% Al2O3 slag at 1430 ??C and a measured rate of 2.7 ??10 -5 g/cm2.s was obtained. The dissolution rate was increased by slag chemistry and ranged from 6.5??10-5 to 2.1??10-4 g/cm2.s. The dissolution rate of CaO was measured in CaO ??? 42 wt% Al2O3 ??? 8% SiO2 based slag. The measured dissolution rates were found to be strongly dependent on the slag chemistry and temperature and ranged from 5.03??10 -5 to 3.3??10 -4 g/cm2.s. The dissolution rates were strongly dependent on the rotation speed and results indicate mass transfer in the slag phase to be rate- limiting step. The diffusivity of MgO / CaO was calculated from the dissolution rate and solubility data, using known mass transfer correlations. The diffusivity of MgO in the calcium aluminate slag at 1430 ??C was found to be about 1.1??10-5 cm2/s. Additions of 5 and 10 wt% Fe2O3 increased the diffusivity by a factor ~ 1.5 to 3, respectively. However, with introduction of (CaF2 5 wt% + Fe2O3 5 wt%) and (CaF2 5 wt% + Fe2O3 10 wt%) in the slag, the diffusivity increased considerably by a factor of about 29 and 11, respectively. The diffusivity of CaO in calcium aluminosilicate was measured to be in the order of 10-6 to 10-5 over a temperature range of 1430 ??? 1600 ??C. CaF2 increased the diffusivity by a factor of 3 to 5 while MnOx and FeOx, ilmenite and TiO 2 increased the diffusivity substantially and SiO2 had an opposite effect. The measured diffusivities are in accord with published data on comparable systems and are discussed with reference to Eyring theory. It was concluded that MnOx, FeOx and ilmenite in the slag increase the dissolution rate and diffusivity of lime, showing comparable results with respect to CaF2.
89

Variability of Particle Fluxes at the SEATS Station, South China Sea

Hsu, Chia-wei 08 February 2010 (has links)
Depth and temporal variability of organic carbon (POC) and total nitrogen (TN) and their isotopic compositions (£_13C and £_15N) in sinking particulate organic matter (POM) collected at the SEATS time-series station (18¢X15¡¦ N; 115¢X50¡¦ E), northern South China Sea, respond closely to the strong seasonality (changes in sea surface temperatures and mixed layer depths) in the surface layer, but are modified considerably by subsequent microbial degradation/remineralization and probably by re-suspension of sediments from the surrounding shelf region in the deep water. Lower C/N and £_15N in summer than the other seasons reflects the change of nutrient supply from NO3-rich, 15N-enriched subsurface waters to N2-fixation-dominated nitrogen source in the surface waters. Below the euphotic zone (>100m), both POC and TN decrease, whereas C/N increases progressively with depth owing to the biodegradation and the preferential removal of more degradable nitrogen-containing compounds through the water column. The C/N increase rate is estimated to be 0.4 unit per 1 km water depth, which is significantly higher than the world average (0.2/km) as a result of the input of higher C/N organic matter from sediments deposited nearby the SEATS site. POC and TN and total particulate mass fluxes decrease sharply within the euphotic zone and continue to decrease all way through the water column to seafloor. For site comparison and global synthesis, an average fraction (e-ratio) of 0.22 of POC exported from the euphotic zone and a POC attenuation rate (b value) of 0.97 are derived. Since the results of this study were obtained from a marginal sea characteristic of strong monsoonal modulation, they should contribute to a better understanding of the fate and pathway of POC in the world ocean.
90

Efficiency Investigation of Exterior-rotor Brushless DC Machine by Three-dimensional Magnetic Flux Analysis

Cheng, Jung-Kuei 19 June 2001 (has links)
The object of this thesis is to investigate the performance in detail and to improve the efficiency of an exterior-rotor burshless DC motor provided by a motor manufacturing company. The finite element software package FLUX3D will be adopted to conduct all the analyzing works. At first, the three-dimensional static magnetic model of the machine will be formulated by FLUX3D. After confirming the preliminary analyzing results with practical measurements, static magnetic circuit of the machine system will be established to seek the possible flux leakage paths. By adjusting the thickness of permanent magnets and the shapes of stator poles, the effectiveness of machine operational efficiency improvements as well as induced torque changes will be obtained. Finally, from these investigations, adequate suggestions for design and construct the associate machine will be provided.

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