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Showing 61 to 69 of 69 (0.03 seconds)Spelling suggestions: "subject:"constancy"" "subject:"constancy4""
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Patterns of change in epistemic frameworks : a reformational perspective / Ruth Ananka LoubserLoubser, Ruth Ananka January 2012 (has links)
The aim of this project is to discern possible patterns in the changes of epistemic frameworks and in the
way in which factors cause or stimulate such changes. Article 1 illustrates forms of consensus between
the views of various prominent 20th century philosophers of science on the characteristics and functions
of pre-scientific frameworks in scientific activity. This is done by highlighting various helpful insights
from the reformational tradition as a point of departure. Article 2 attempts to achieve more clarity on
how changes in epistemic frameworks occur, whilst article 3 discerns the factors influencing framework
change. Article 4 illustrates and evaluates the relationship between change and constancy in the
viewpoints of various philosophers and scientists throughout history. The project suggests that change
and constancy can be related to epistemic frameworks according to a pattern referring to the
irreducibility of coherents where change and constancy exist in cohesion. As a consequence, change is
never completely random or absolute. Although a broad variety of factors play a role in framework
changes, a pattern can be discerned in the sense that some factors play a regulative role, so that change
is dynamic but not arbitrary. / Thesis (PhD (Philosophy))--North-West University, Potchefstroom Campus, 2013
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Modelling and forecasting economic time series with single hidden-layer feedforward autoregressive artificial neural networks /Rech, Gianluigi, January 1900 (has links)
Diss. Stockholm : Handelshögskolan, 2002.
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Underlag för projektering av sockelkonstruktioner : En kvalitativ analys av sockelkonstruktionen utifrån kriterierna funktion, byggbarhet, beständighet och utformning / A Guide for Base Construction : A Qualitative Analysis of the Connection Between Outer Wall and Ground PlateGustafson, Anna, Krogh, Jenny January 2019 (has links)
Sockelkonstruktionen är en del av grundkonstruktionen i en byggnad där yttervägg möter mark. Den är en utsatt del av en byggnads klimatskärm och exponeras både för det svenska klimatet och markfukt. Projektering av en sockelkonstruktion är tidskrävande och kräver stor kunskap inom flera områden för att uppnå de krav som ställs. Syftet med denna rapport är att underlätta och förbättra projekteringen av sockelkonstruktioner hos uppdragsgivande byggkonstruktionsföretaget Kåver & Mellin. För att uppfylla syftet är målet att rapporten ska fungera som ett vägledande underlag som kan användas vid projektering av sockelkonstruktioner. Underlaget ska utgå från kriterierna funktion, beständighet, byggbarhet och utformning. Genom en litteraturstudie i kombination med kvalitativ datainsamling och kvalitativa intervjuer med sakkunniga i byggbranschen framställdes resultatet. Detta har legat till grund för analys och slutsats. Resultatet visar att det finns många sätt att utforma en sockelkonstruktion för att uppnå det krav som ställs. Viktiga faktorer vid utformning av sockelkonstruktioner är byggprojektets förutsättningar och de i sockelkonstruktionen ingående delarnas möten och material. Mer ingående rekommendationer återfinns i rapporten under slutsatser. Resultatet indikerade också att det inte finns tydliga regler för hur sockelkonstruktioner ska utföras. Olika regelverk tolkas olika vilket visar på ett behov av att informationen tydliggörs. Denna rapport kan ses som ett vägledande underlag att använda vid projektering av sockelkonstruktioner. / The base of the construction where the outer wall is connected to the ground plate is the connection dealt with in this report. We refer to it as the base. The base leads the loads from the building down to the ground and is supposed to protect the building from outer impact. This part of the building shell is well exposed with the Swedish climate and in constant contact with wet ground. Forming a base is difficult in many ways and demands knowledge in many different areas. It takes a great amount of time and it is hard to be sure that you fulfill the specific demand of each construction in each project. The aim of this report is to make the process of forming a base easier and better for the sponsoring company Kåver & Mellin. The report is supposed to lead to a written report that could be used as a guide when forming bases. The report is based on the four criterias: function, constructability, constancy and shaping. The result came from studying literature, interviewing experts in the branch of building construction combined with sorting drawings of bases from former projects at Kåver & Mellin. The result has been analyzed and lead to several wide and narrow conclusions about bases. The result showed that there are many ways of forming a base to reach the demand of each project. Aspects to think about when forming a base is the demands of each project and the materials and connections in the base. The result also showed that there are no clear directions of how to form a base in a building. Different laws and rules can be read in different ways depending on who is reading which shows that the guidelines could be clearer. This report is a guide of how to think when forming a base in a building.
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True Color Measurements Using Color Calibration TechniquesWransky, Michael E. 15 September 2015 (has links)
No description available.
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Total variational optical flow for robust and accurate bladder image mosaicing / Calcul du flot optique dans une approche variationnelle totale pour le mosaïquage robuste et précis d’images de la vessieAli, Sharib 04 January 2016 (has links)
La cystoscopie est l’examen de référence pour le diagnostic et le traitement du cancer de la vessie. Le champ de vue (CdV) réduit des endoscopes complique le diagnostic et le suivi des lésions. Les mosaïques d’images sont une solution à ce problème car elles visualisent des CdV étendus. Toutefois, pour la vessie, le mosaïque d’images est un véritable défi à cause du faible contraste dans les images, des textures peu prononcées, de la variabilité intra- et inter-patient et des changements d’illumination dans les séquences. Ce défi est également à relever dans d’autres modalités endoscopiques ou dans des scènes non médicales comme les vidéos sous-marines. Dans cette thèse, une énergie variationnelle totale a d’abord été minimisée à l’aide d’un algorithme primal-dual du premier ordre pour obtenir un flot optique fournissant une correspondance dense et précise entre les points homologues des paires d’images. Les correspondances sont ensuite utilisées pour déterminer les paramètres des transformations requises pour le placement des images dans le repère global de la mosaïque. Les méthodes proposées pour l’estimation du flot optique dense incluent un terme d’attache aux données qui minimise le nombre des vecteurs aberrants et un terme de régularisation conçu pour préserver les discontinuités du champ devecteurs. Un algorithme de flot optique qui est robuste vis-à-vis de changements d’illumination importants (et utilisable pour différentes modalités) a également été développé dans ce contexte. La précision et la robustesse des méthodes de recalage proposées ont été testées sur des jeux de données (de flot optique) publiquement accessibles et sur des fantômes de vessies et de la peau. Des résultats sur des données patients acquises avec des cystoscopes rigides et flexibles, en lumière blanche ou en fluorescence, montrent la robustesse des algorithmes proposés. Ces résultats sont complétés par ceux obtenus pour d’autres séquences endoscopiques réelles de dermatoscopie, de scène sous-marine et de données d’exploration spatiale. / Cystoscopy is the reference procedure for the diagnosis and treatment of bladder cancer. The small field of view (FOV) of endoscopes makes both the diagnosis and follow-up of lesions difficult. Image mosaics are a solution to this problem since they visualize large FOVs of the bladder scene. However, due to low contrast, weak texture, inter- and intra-patient texture variability and illumination changes in these image sequences, the task of image mosaicing becomes challenging. This is also a major concern in other endoscopic data and non-medical scenes like underwater videos. In this thesis, a total variational energy has been first minimized using a first-order primal-dual algorithm in convex optimization to obtain optical flow vector fields giving a dense and accurate correspondence between homologous points of the image pairs. The correspondences are then used to obtain transformation parameters for registering the images to one global mosaic coordinate system. The proposed methods for dense optical flow estimation include a data-term which is modeled to minimize at most the outliers and a regularizer which is designed to preserve at their best the flow field discontinuities. An optical flow algorithm, which is robust to strong illumination changes (and which suits to different modalities), has also been developed in this framework. The registration accuracy and robustness of the proposed methods are tested on both publicly available datasets for optical flow estimation and on simulated bladder and skin phantoms. Results on patient data acquired with rigid and flexible cystoscopes under the white light and the fluorescence modality show the robustness of the proposed approaches. These results are also complemented with those of other real endoscopic data, dermoscopic sequences, underwater scenes and space exploration data.
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A Study of Gamma Distributions and Some Related WorksChou, Chao-Wei 11 May 2004 (has links)
Characterization of distributions has been an important topic in statistical theory for decades. Although there have been many well known results already developed, it is still of great interest to find new characterizations of commonly used distributions in application, such as normal or gamma distribution. In practice, sometimes we make guesses on the distribution to be fitted to the data observed, sometimes we use the characteristic properties of those distributions to do so. In this paper we will restrict our attention to the characterizations of gamma distribution as well as some related studies on the corresponding parameter estimation based on the characterization properties. Some simulation studies are also given.
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Walter Benjamin und die Kunst des GraphischenMatsui, Takaoki 16 June 2008 (has links)
Als Bild- und Medientheoretiker hinterließ Walter Benjamin nicht nur die berühmte „materialistische“ Auratheorie, sondern auch scheinbar esoterische Theorien der bildenden Kunst. Der Zusammenhang und Inhalt der beiden Theorien können erhellt werden, wenn wir genauer sehen, wie er sich dort mit der Beschreibung der Kindheit beschäftigte. Der Ursprung seiner Auratheorie liegt in seiner „Tagebuch“-Literatur, wo er in die melancholisch gefärbten Visionen der „Jugend“ zu versinken pflegte. Der topologische Aufbau dieser Visionen – ihre eigenartig „photo-graphische“ Struktur – soll mithilfe der Zweiten Topik Freuds analysiert werden. Und aufgrund dieser Analyse werden wir eine Revision der üblichen (übersimplifizierten) Gegenüberstellung von seinem historischen Materislismus und dem „apolitischen Formalismus“ Clement Greenbergs vornehmen. Greenbergs Kunstkritik dient aber auch zur Entschlüsselung der „esoterischen“ Bildtheorien Benjamins. Die letzteren verwirren uns vor allem deshalb, weil dort das Sehen der Kinder zuerst (um 1915) irreführender Weise nach den üblichen Dichotomien der Romantik (Linie / Farbe; männlich / weiblich; erwachsen / kindlich…) beschrieben worden war; ihren eigentlichen Inhalt konnte Benjamin erst präzisieren, als er – anhand seiner Betrachtungen der graphischen „Horizontalität“ und nach seinen Spekulationen über das magische Wesen von „Zeichen“ und „Mal“ (1917) – eine Trichotomie der Bildgattungen (Malerei / Graphik / getuschtes Bild) aufgestellt hatte. Wir rekonstruieren diese Theorieentwicklungen nicht nur durch detaillierte Bild- und Textanalysen, sondern auch unter Heranziehung seines „materialistischen“ Spätwerks (der Passagenarbeit und der „Berliner Kindheit“), da erst im letzteren der einzigartige Zusammenhang zwischen seinen frühen Bildtheorien und seiner Geldtheorie als „Konstellation“ sichtbar werden sollte. / Walter Benjamin’s writings on visual arts include not only the famous „materialistic“ essays on aura but also seemingly esoteric notes on painting and the graphic arts. The content and correlation of all these writings become clear once we grasp how they perform the task of describing childhood experience. His theory of aura was prefigured in his philosophical „Diaries“ where his struggle with his depression was often followed (or interrupted) by dreamlike visions of "youth". The discursive structure of these visions – which will prove to be a strangely „photo-graphic“ one – is to be analyzed by using the second Freudian topology as a comparison. Through this analysis we will be able to reconsider the well-known (oversimplified) antagonism between his historical materialism and the „apolitical formalism“ of Clement Greenberg from a new viewpoint. Greenberg’s criticism helps us also to decipher the „esoteric“ texts of Benjamin. They puzzled scholars especially because they described children’s vision at first (about 1915) misleadingly in accordance with the conventional dichotomies of Romanticism (line / color; masculine / feminine; adult / child…); Benjamin could specify their original implication only after he had set up – based on his reflexions on the „horizontality“ of the graphic arts, and by speculating further on the magic nature of „Zeichen“ and „Mal“ (1917) – a trichotomy of genres (painting / the graphic arts / ink and watercolor illustrations). We will reconstruct this development of his theory not only through detailed analyses of related works of art but also in view of his „materialistic“ late writings (the Arcades Project and „Berlin Childhood“), for it is only there that we find out an essential relation – a singular „constellation“ – of his early art theory and his theory of money.
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Methodological investigations on vegetation typology and phytogeography of rain forests of tropical AfricaSenterre, Bruno B.M.L. 17 June 2005 (has links)
I. An original methodological discussion is proposed on the problem of the typology of tropical rain forest’s plant communities, based on the study of forest types across gradients of continentality and elevation, within Atlantic central Africa. These investigations were based on the statement that the main problems in forest typology are related to the non-zonal or zonal character of the different vegetation types and to non considering the relations and differences between forest strata.
II. Field data consisted in phytosociological homogeneous sample plots localized within different recognized phytogeographical entities, in a region of tropical Africa where these entities are known to be well conserved. A total of 37 such plots were inventoried in the region extending from the littoral forests of Ndoté, Equatorial Guinea, which are wet evergreen forests, to the continental forests of the Dja, Cameroon, known as evergreen seasonal forests. The studied region also included the oriental Atlantic forests of Equatorial Guinea, known as moist evergreen forests or caesalp forests. In various parts of this continentality gradient, some plots were localized within climax non-zonal formations, namely the submontane rain forests. The emphasis was put on the vegetation of the Monte Alén National Park.
The sampling methodology was willing to be as "complete ", including all strata, "quantitative ", enumerating all individuals, and "representative ", within each stratum, as possible. These multi-layers plots were realised using nested sub-plots, with a sampling size of 100 individuals for every ligneous stratum recognized (dominant trees, dominated trees and shrubs) and a sampling size of 200m² for the herbaceous and suffrutex stratum.
Forest types were defined independently for each stratum and the differences were analysed. A method was proposed for the simultaneous analysis of all floristic data, converting and standardizing the values from ligneous strata, on the one hand, and from understorey strata, on the other hand.
III. Ten forest types were described using IndVal and discussed in the general context of the guineo-congolian region, from a syntaxonomic view point (agglomerative classification) and from a phytogeographical view point (divisive classification). Homologies between these two approaches are described. The proposed phytogeographical system is based on an "open " conception of hierarchical classifications, combining advantages of agglomerative and divisive classifications. In concrete terms, the non-zonal criteria, for example the submontane variants, are categorised separately and in analogy with the zonal criteria, related to the usual phytochoria.
Analysis of ecological relationships for the 10 communities showed that the main variables related to the floristic variability in our mainland rain forests are elevation, rainfall, hygrometry (estimated using bryophytes cover levels) and distance to the ocean. The two extremes on the vertical microclimatic gradient, dominant trees stratum and herbaceous stratum, give similar typologies, however canonical analysis showed that for the herbaceous layer, non-zonal variables (hygrometry and elevation) were gaining more importance when the influence of the two zonal variables was attenuated. In every case, spatial autocorrelation was less important than the environment in explaining floristic variability but its role increased in the spatial arrangement of understorey species, whose dispersal capacity is generally lower than canopy trees. The phytosociological, phytogeographical and ecological description of forest types is accompanied by a physiognomical description using biological types spectrum, as well as architectural models, leaf sizes, etc.
With regard to diversity, we have demonstrated that species richness was higher from upper to lower strata because of the accumulation in lower strata of species from various strata. On the other hand, the proper stratum diversity, i.e. the structural set, decreased from dominant trees to shrubs. The proper diversity of the herb layer showed relatively high figures mainly due to the higher individual density in relation to the existence of microstrata. Within the 37 sample plots, 1,050 taxa have been identified to species or morpho-species levels, for a total of 25,750 individuals. These taxa represent 442 genus among 104 families. The richest forest type is found on the foothills of the Niefang range, on the windward side. This forest type is also characterised by a high number of oligotypic genus and by species belonging to functional types indicators of glacial refuges. These functional types are defined on the basis of the dispersal capacity and on kind of stand needed for effective germination. We formulated the hypothesis that this kind of "foothills refuge ", characterised by his zonal nature, could have been one of the rare refuges for species from mainland rain forests, while montane and fluvial refuges would mainly have preserved species from non-zonal forest types: (sub)montane and riverine.
Based on indicator species of submontane forests, a potential distribution map of this forest type has been realised at the Atlantic central African scale. More than 400 submontane forest localities have been mapped. These forests begin at 400m of altitude near the ocean, and progressively at higher altitude for increasing distance to the ocean. Many lowland localities also comprised submontane species, which could indicate the existence of ecological transgressions. These transgressions would allow migratory tracks for submontane species between isolated mountain ranges, not only during glacial periods, through heights at the northern and southern borders of the congo basin, but also contemporarily through the lowland riverine forest network, in the centre of this basin. Finally, a special attention has been attributed to littoral forests and to some cases of choroecological transgressions, coupled to the ecological equalization phenomenon.
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Recherches méthodologiques pour la typologie de la végétation et la phytogéographie des forêts denses d'Afrique tropicaleSenterre, Bruno 17 June 2005 (has links)
I. An original methodological discussion is proposed on the problem of the typology of tropical rain forest’s plant communities, based on the study of forest types across gradients of continentality and elevation, within Atlantic central Africa. These investigations were based on the statement that the main problems in forest typology are related to the non-zonal or zonal character of the different vegetation types and to non considering the relations and differences between forest strata.<p><p>II. Field data consisted in phytosociological homogeneous sample plots localized within different recognized phytogeographical entities, in a region of tropical Africa where these entities are known to be well conserved. A total of 37 such plots were inventoried in the region extending from the littoral forests of Ndoté, Equatorial Guinea, which are wet evergreen forests, to the continental forests of the Dja, Cameroon, known as evergreen seasonal forests. The studied region also included the oriental Atlantic forests of Equatorial Guinea, known as moist evergreen forests or caesalp forests. In various parts of this continentality gradient, some plots were localized within climax non-zonal formations, namely the submontane rain forests. The emphasis was put on the vegetation of the Monte Alén National Park.<p><p>The sampling methodology was willing to be as "complete ", including all strata, "quantitative ", enumerating all individuals, and "representative ", within each stratum, as possible. These multi-layers plots were realised using nested sub-plots, with a sampling size of 100 individuals for every ligneous stratum recognized (dominant trees, dominated trees and shrubs) and a sampling size of 200m² for the herbaceous and suffrutex stratum.<p><p>Forest types were defined independently for each stratum and the differences were analysed. A method was proposed for the simultaneous analysis of all floristic data, converting and standardizing the values from ligneous strata, on the one hand, and from understorey strata, on the other hand.<p><p>III. Ten forest types were described using IndVal and discussed in the general context of the guineo-congolian region, from a syntaxonomic view point (agglomerative classification) and from a phytogeographical view point (divisive classification). Homologies between these two approaches are described. The proposed phytogeographical system is based on an "open " conception of hierarchical classifications, combining advantages of agglomerative and divisive classifications. In concrete terms, the non-zonal criteria, for example the submontane variants, are categorised separately and in analogy with the zonal criteria, related to the usual phytochoria.<p><p>Analysis of ecological relationships for the 10 communities showed that the main variables related to the floristic variability in our mainland rain forests are elevation, rainfall, hygrometry (estimated using bryophytes cover levels) and distance to the ocean. The two extremes on the vertical microclimatic gradient, dominant trees stratum and herbaceous stratum, give similar typologies, however canonical analysis showed that for the herbaceous layer, non-zonal variables (hygrometry and elevation) were gaining more importance when the influence of the two zonal variables was attenuated. In every case, spatial autocorrelation was less important than the environment in explaining floristic variability but its role increased in the spatial arrangement of understorey species, whose dispersal capacity is generally lower than canopy trees. The phytosociological, phytogeographical and ecological description of forest types is accompanied by a physiognomical description using biological types spectrum, as well as architectural models, leaf sizes, etc.<p><p>With regard to diversity, we have demonstrated that species richness was higher from upper to lower strata because of the accumulation in lower strata of species from various strata. On the other hand, the proper stratum diversity, i.e. the structural set, decreased from dominant trees to shrubs. The proper diversity of the herb layer showed relatively high figures mainly due to the higher individual density in relation to the existence of microstrata. Within the 37 sample plots, 1,050 taxa have been identified to species or morpho-species levels, for a total of 25,750 individuals. These taxa represent 442 genus among 104 families. The richest forest type is found on the foothills of the Niefang range, on the windward side. This forest type is also characterised by a high number of oligotypic genus and by species belonging to functional types indicators of glacial refuges. These functional types are defined on the basis of the dispersal capacity and on kind of stand needed for effective germination. We formulated the hypothesis that this kind of "foothills refuge ", characterised by his zonal nature, could have been one of the rare refuges for species from mainland rain forests, while montane and fluvial refuges would mainly have preserved species from non-zonal forest types: (sub)montane and riverine.<p><p>Based on indicator species of submontane forests, a potential distribution map of this forest type has been realised at the Atlantic central African scale. More than 400 submontane forest localities have been mapped. These forests begin at 400m of altitude near the ocean, and progressively at higher altitude for increasing distance to the ocean. Many lowland localities also comprised submontane species, which could indicate the existence of ecological transgressions. These transgressions would allow migratory tracks for submontane species between isolated mountain ranges, not only during glacial periods, through heights at the northern and southern borders of the congo basin, but also contemporarily through the lowland riverine forest network, in the centre of this basin. Finally, a special attention has been attributed to littoral forests and to some cases of choroecological transgressions, coupled to the ecological equalization phenomenon.<p> / Doctorat en sciences agronomiques et ingénierie biologique / info:eu-repo/semantics/nonPublished
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