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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.
1

Characterization of potential source rocks of the Prince Albert, Whitehill and Collingham formations in the Laingsburg sub-basin, South Africa

Ferreira, Janine Connie January 2014 (has links)
>Magister Scientiae - MSc / The present research deals with the characterization of the Lower Ecca Group in terms of sedimentology, mineralogy and organic geochemistry. A field study was conducted in order to characterize the sedimentology and thereby determine the environments of deposition of the Prince Albert, Whitehill and Collingham Formations. In addition, shale samples were subjected to geochemical and mineralogical analyses so as to ascertain its source rock properties. The study utilized X-ray diffraction (XRD), scanning electron microscopy with an energy dispersive spectrometer (SEM-EDS), total organic carbon (TOC) and Rock-Eval pyrolysis to determine the mineralogy and organic geochemistry of shale from the formations under investigation. The sedimentological investigation revealed that the upper Prince Albert Formation is dominated by shale with thin beds of carbonate. These shales are interpreted to have been deposited by suspension settling in a marine environment which was occasionally interrupted by deposition of carbonates that form in a shallow marine environment. The overlying Whitehill Formation consists predominantly of carbonaceous shale with relatively more resistant shale beds also present. The fine sediments are interpreted to have been deposited from suspension settling under anoxic bottom conditions which would favor the preservation of organic rich material. Deposition of the Whitehill Formation was followed by the Collingham Formation which is dominated by rhythmic deposits of shale and sandstone that are occasionally interrupted by tuff layers. The clay size sediments are interpreted to have been deposited from suspension settling which are interbedded with low density turbidite current deposits in a marine environment. Based on the findings of the field study, it is apparent that the Prince Albert and Collingham Formations were deposited in marine environments, with the Whitehill Formation being deposited in an anoxic environment. These environments are known to be dominated by phytoplanktonic organisms and algal debris, and as such shales deposited in these environments contain predominantly Type I (derived from algae) and II kerogen (derived from plankton). It can therefore be postulated that Type I and II kerogens are the dominant constituents of organic matter in the Lower Ecca Group shales. Mineralogically, the shales consist chiefly of kaolinite, smectite and illite clay minerals, which are derived from a combination of weathering of feldspars, and the alteration of other clay minerals. The latter being inferred from the existence of albite in all the studied shale samples, pyroclastic material observed in the field, as well as the occurrence of alteration along clay mineral edges.
2

Palynological, Palynofacies, Paleoenvironmental and Organic Geochemical Studies on the Upper Cretaceous Succession of the GPTSW-7 Well, North Western Desert, Egypt

El Beialy, Salah Y., El Atfy, Haytham S., Zavada, Michael S., El Khoriby, Essam M., Abu-Zied, Ramadan H. 01 February 2010 (has links)
The present study of the Abu Roash and Bahariya formations in well GPTSW-7 refines our understanding of the subsurface Cretaceous of the north Western Desert of Egypt. Our investigations are based on the palynological analyses of 71 cuttings samples, of which 24 have also been analyzed for geochemistry, in addition to 3 sidewall cores analyzed for vitrinite reflectance (Ro). Four palynological zones and three subzones in addition to a poorly fossiliferous interval ranging in age from Coniacian-Santonian to early Cenomanian are proposed. These include a poorly fossiliferous interval (Coniacian-Santonian), Dinogymnium vozzhennikovae Interval Zone (late to middle Turonian), Ephedripites ambiguus-Ephedripites multicostatus-Foveotricolpites giganteus-Foveotricolpites gigantoreticultus Assemblage Zone (early Turonian), Classopollis brasiliensis Interval Zone (late to middle Cenomanian), and Afropollis jardinus Interval Zone (early Cenomanian). The succeeding subzones are; Afropollis kahramanensis Interval Subzone, Elaterosporites klaszii Interval Subzone and Cretacaeiporites densimurus Interval Subzone, all of early Cenomanian age. Total organic carbon (TOC) and Rock-Eval pyrolysis and palynofacies analyses indicate that the Bahariya Formation and the Abu Roash G Member are primarily of kerogen III type and hence gas prone, suggesting a strong influence of hydrogen-enriched organic matter. The Abu Roash A, C-E Members may also be gas prone (type III kerogen) and appear to contain highly oxidized terrestrial organic matter. In contrast, the Abu Roash F Member has very high TOC and HI values and contains a very high proportion of amorphous organic matter (AOM) indicating a highly oil-prone facies. While this finding is not unexpected for anoxic black shale, it contrasts with earlier studies that suggest a gas prone nature. Ro measurements show that the Bahariya Formation represents an immature-early genesis dry gas phase. This is also true for all investigated samples from the Abu Roash and Bahariya formations, based on their low thermal alteration index (TAI). Quantitative and qualitative analyses of both the palynoflora and palynofacies show that the Abu Roash A and C Members (B is missing), both of Coniacian-Santonian age, represent oxic proximal and distal shelf environment. The Abu Roash D and E Members, dated as Turonian, represent oxic (proximal) shelf, whereas the Cenomanian Abu Roash F Member was deposited in a distal suboxic-anoxic basin. The Cenomanian Abu Roash G Member and the Bahariya Formation were deposited in a shallow marine and shallow marine to fluvio-deltaic setting, respectively. The Senonian Palmae Province is recognized in the palynoflora by the presence of Proteacidites, Auriculiidites reticulatus, Ariadnaesporites, Gabonisporis vigourouxii. On the other hand the Albian-Cenomanian Elaterates Province is characterized by the presence of Steevesipollenites, Gnetaceaepollenites, Elaterocolpites, Elaterosporites, Elateroplicites, Senegalosporites, Sofrepites, Afropollis and Cretacaeiporites.
3

Nature et mode d'assemblage des constituants minéraux et organiques dans des Ferralsols de la région des Cerrados (Brésil). Evolution après mise en culture

Volland-Tuduri, Nathalie 23 March 2005 (has links) (PDF)
Les Ferralsols se caractérisent par une microstructure très développée dont dépend étroitement leur fertilité. Cette microstructure repose sur des microagrégats très stables, de 50 à 800 µm de diamètre. Sous végétation naturelle comme sous pâturage, la densité apparente des sols, la taille et le mode d'assemblage des microagrégats, ainsi que la caractérisation de la matière organique, ont permis de mettre en évidence d'importantes variations avec la profondeur. Nous avons établi une typologie du mode d'assemblage des microagrégats ainsi qu'un modèle mettant en relation structure et porosité. La matière organique se singularise, en pyrolyse, par une composante de haute température, d'origine conjecturale, mais très probablement due à un effet de matrice minérale. L'ensemble des variations observées ne peuvent a priori s'expliquer par des différences d'usage du sol, mais plutôt grâce à l'activité des insectes sociaux qui sont vraisemblablement à l'origine des microagrégats.
4

Rhapsody in Red: Jazz and a Soviet Public Sphere Under Stalin

January 2017 (has links)
abstract: This dissertation describes the public sphere that coalesced in the Soviet jazz scene during Josef Stalin’s reign. Scholars debate the extent to which Soviet citizens, especially under Stalin, were coerced into cooperating with the regime through terror; willingly cooperated with the regime out of self-interest; or re-aligned their speech, behavior, and thoughts to conform to Bolshevik ideology and discourse. In all cases, citizens were generally unable to openly express their own opinions on what Soviet society should look like. In this dissertation, I attempt to bridge this gap by analyzing the diverse reactions to jazz music in Josef Stalin’s Soviet Union. I argue that audience engagement with jazz and discussions about the genre in the Soviet press and elsewhere were attempts to grapple with bigger questions of public concern about leisure, morality, ethnicity, cosmopolitanism and patriotism in a socialist society. This jazz public sphere was suppressed in the late 1940s and early 1950s because of Cold War paranoia and fears of foreign influences in Soviet life. In its place, a counterpublic sphere formed, in which jazz enthusiasts expressed views on socialism that were more open and contradictory to official norms. This counterpublic sphere foreshadowed aspects of post-Stalinist Soviet culture. To support my arguments, I employ archival documents such as fan mail and censorship records, periodicals, memoirs, and Stalin-era jazz recordings to determine the themes present in jazz music, how audiences reacted to them, and how these popular reactions overlapped with those of journalists, musicologists, bureaucrats, and composers. This project expands our understanding of when and where public spheres can form, challenges top-down interpretations of Soviet cultural policy, and illuminates the Soviet Union and Russia’s ambivalent relationship with the West and its culture. / Dissertation/Thesis / Doctoral Dissertation History 2017
5

Impact des taillis à très courte rotation de saules sur les propriétés fonctionnelles des sols et définition d'indicateurs de qualité / Willow Short Rotation Coppice (SRC) effect on soil functional properties and quality indicators definition

Stauffer, Marie 02 April 2014 (has links)
Les Taillis à Très Courte Rotation sont une culture destinée à produire des plaquettes de bois énergie. L'objectif de la thèse était d'étudier l'impact des TTCR sur le fonctionnement des sols et de proposer des indicateurs de qualité. Cinq prélèvements ont été effectués chaque printemps et automne entre 2010 et 2012 sur les sols de quatre couples de TTCR et bandes enherbées, d'une forêt alluviale et d'un agrosystème, localisés dans la vallée de l'Aisne. Les paramètres suivants ont été mesurés: matières organiques, carbone total, capacité d'échange cationique et éléments échangeables, phosphore disponible, minéralisation du carbone et de l'azote, biomasse, abondance et diversité des communautés lombriciennes, abondance relative et diversité des communautés fongiques et bactériennes, activités enzymatiques, caractérisations physiques et chimiques des matières organiques. 6 années après la mise en place des TTCR, les densités fongiques et lombriciennes, la respiration basale, l'activité laccase étaient plus élevées dans les TTCR par rapport à l'agrosystème. Ces modifications peuvent être reliées aux changements quantitatifs et qualitatifs des matières organiques (augmentation du C/N, diminution de l'indice hydrogène). L'azote et le phosphore semblent être limitant mais les retours importants et le turn over rapide de la MO viennent tamponner les fortes exportations. Ces mesures ont conduit à la définition d'indicateurs et aboutissent à la proposition de trois indices : fertilité, activité biologique, abondance et diversité des communautés biologiques. L'utilisation des courbes de réponses principales confirme l'effet positif des TTCR sur la qualité du sol, observée avec le calcul d'indices synthétiques / Short Rotation Coppices (SRC) are a crop system intended to produce energy wood chips. This thesis aimed at assessing the impact of SRC on soil functioning and proposing quality indicators. Five samplings were performed in spring and autumn between 2010 and 2012 on plots including four couples of SRC and grassland, an alluvial forest and an agrosystem, in the Aisne valley. The following parameters were monitored: organic matter, total carbon, cation capacity exchange, available phosphorus, carbon and nitrogen basal respiration, earthworm biomass, density and diversity, fungal and bacterial density and diversity, enzymatic activity, physical and chemical organic matter characterisations. 6 years after conversion to SRC, earthworm and fungal density, basal respiration and laccase activity were higher in SRC soil compared to conventional agrosystem. These changes can be linked to qualitative and quantitative organic matter evolutions (increase of the C/N ratio and decrease of hydrogen index). Nitrogen and phosphorus seemed to be limiting factors for SRC crop yields. However, soil nutrient return and the good turnover of organic matter can buffer strong exportations. The measured parameters led to indicator definition and proposition of three indices: fertility, biological activity, density and diversity of biological communities. Principal response curves confirmed the positive effect of SRC on soil quality as observed with synthetic indices calculation
6

Étude pétrographique et géochimique intégrée du charbon et de shale à gaz du bassin Sabinas et de Chihuahua au Nord du Mexique : estimation des ressources en gaz méthane / Petrographic and geochemical study integrated coal and shale gas from Sabinas basin and Chihuahua in northern Mexico : estimation of gas methane resources

O Burrola, Francisco de la 14 December 2013 (has links)
Une étude de caractérisation intégrée de pétrographie et géochimie organique a été réalisée dans les bassins de Sabinas et Chihuahua au Nord-Est du Mexique. Ces informations ont permis une modélisation numérique de la formation du gaz en considérant la subsidence thermique des charbons et des shales à gaz. Les objectifs de cette thèse sont les suivants: mise en place d'une méthodologie de caractérisation des roches étudiées ; estimation du potentiel générateur de gaz et sa distribution régionale ; estimation des ressources en gaz méthane. Les analyses effectuées sur l'ensemble des échantillons ont permis de caractériser la roche, les kérogènes, les huiles et les gaz. La méthodologie utilisée permet de croiser les informations pétrographiques et géochimiques pour pouvoir analyser le système pétrolier par modélisation numérique. Les analyses réalisées sont: réflectance% Ro, analyse élémentaire et immédiate, Rock Eval6 ® (Bulk Rock), [delta]13C, [delta]D, (gaz de charbon), microscopie électronique à balayage, analyse d'images, analyse des macéraux et inclusions fluides. Un programme informatique a été construit afin de croiser l'information des analyses des échantillons avec celle des expériences de maturation artificielle en laboratoire. Cette démarche nous à permis d'estimer les ressources en gaz méthane à la fois généré par les charbons et les shales gaz. La méthodologie utilisée pour l'étude des kérogènes et des gaz dans les deux bassins est à notre avis la plus appropriée pour répondre aux objectifs proposés dans ce travail de thèse. Celle-ci permet de caractériser l'évolution thermique des charbons, shales gas (gaz de schiste), et roches mères pétrolières / This comprehensive characterization study was performed using organic petrology and geochemistry conducted in the Sabinas basin and Chihuahua in northern Mexico. This information allowed a numerical modeling of gas formation, considering the thermal subsidence of coal and carbonaceous shales.The objectives of this thesis are: establish a characterization methodology for the studied rocks ; estimate potential gas generator and its regional distribution ; estimate the methane gas resources. For the development of this project, we conducted an intensive campaign representative sampling of coal, carbonaceous shales and coal gas "in situ". For the Sabinas basin were studied 97 samples and 114 samples in the basin of Chihuahua. The analyses carried out that were used on the samples analyzed allowed to characterize the kerogen and gas. The methodology used to cross petrographic and geochemical information to analyze the petroleum system by numerical modeling. Analyses were: Petrographic, reflectance %Ro, elemental analysis and immediate, Rock Eval6 ® (Bulk rock), isotopic analysis, [delta]13C, [delta]D, (coal gas), scanning electron microscopy, image analysis and analysis of macerals fluid inclusions. The analyzes that were used on the samples allowed to characterize the sample, the kerogen and gas. The methodology used to cross petrographic and geochemical information for analyze the oil system by numerical modeling. Analyses were: Petrographic, reflectance% Ro, elemental analysis and immediate, Rock Eval6 ® (Bulk rock), isotopic analysis, d13C, dD, (coal gas), scanning electron microscopy, image analysis and analysis of macerals fluid inclusions. A computer program was constructed to cross the information with the analysis of samples of artificial maturation experiments in the laboratory. This approach allowed estimation of methane gas resources generated by coal and carbonaceous shales. [...] In conclusion, between the two basins studied, the Sabinas basin, generates more gas for industrial exploitation. However, the rocks of the basin of Chihuahua unconventional types (shale gas) show good potential for hydrocarbon generation. The methodology used for the study of kerogen and gas in the two basins is in our opinion the most appropriate to meet the objectives proposed in this thesis. This allows to characterize the thermal evolution of coal, carbonaceous shale (shale gas), coal gas and hydrocarbon source rocks
7

Klíčové faktory akumulace půdní organické hmoty / Key factors in soil organic matter accumulation

Vindušková, Olga January 2017 (has links)
Soil organic matter (SOM) is highly important for soil quality and the global carbon cycle. SOM content is influenced by a complex interplay of many different factors such as time, climate, parent material, vegetation, and others. The effect of time is often studied using the chronosequence approach using a set of study sites differing in age but comparable in other soil-forming factors. The effect of other factors can be studied by comparing two or more chronosequences. An important assumption of these approaches is that the SOM quantification methods produce comparable results both among sites of each sequence and among different sequences. In this thesis, I explored the key factors in SOM accumulation and dealt with SOM quantification methods. I studied SOM accumulation in two model situations - in post-mining sites after open-cast coal and oil shale mining and in landslides in the Western Carpathians. The results of this thesis are summarized in one book chapter accepted for publication and four papers, out of which three have been published and one is prepared for publication in an international journal with impact factor. The key factor affecting the rate of SOM accumulation after a major disturbance is time. The accumulation rates found in the first 40 to 100 years in both post-mining sites...
8

Etude de la terminaison méridionale de l'Oural (Mougodjar, Kazakhstan) : évolution tectonique et stratigraphique du bassin d'avant-pays au Paléozoïque (Dévonien à Permien) / Study of southern Urals in Mougodjar (Kazakhstan) : Late Palaeozoic tectonic and stratigraphic evolution of the foreland basin

Abdulanova, Saya 07 July 2017 (has links)
Cette thèse est une étude du bassin d’avant-pays de l’Oural méridional au Kazakhstan (Mougodjar) à partir de données sédimentologiques (affleurements) et de sub-surface (profils sismiques, puits). Une étude sédimentologique des séries turbiditiques d’âge Carbonifère terminal-Permien inférieur a été menée dans le Mougodjar. L’étude des dépôts a permis de caractériser les environnements des dépôts turbiditiques et de mettre en évidence des séquences de long terme se succédant du Carbonifère terminal au Permien inférieur. L’analyse des faciès turbiditiques montre que les séquences de long terme sont contrôlées par les fluctuations du niveau marin global sous contrôle glacio-eustatique. L’orogenèse du Permien inférieur associée à la surrection de l’Oural a contrôlé le volume et la nature des apports sédimentaires alimentant le bassin d’avant-pays. Ceci se traduit par l’importance variable des conglomérats et brèches de démantèlement du matériel volcanique et des plate-formes carbonatées situées sur les marges du bassin et par des réorganisations locales des pentes sous-marines (changements de sens des paléo-courants). Les minéraux smectitiques dominent les assemblages argileux analysés dans les séries du Carbonifère terminal au Permien inférieur. L’illite, la kaolinite et la chlorite sont présentes en plus faibles proportions. Les assemblages argileux indiquent une relative pérennité des apports détritiques qui varient au cours du temps selon la distribution des faciès turbiditiques. Les fluctuations climatiques n’apparaissent pas contrôler la distribution des minéraux argileux qui semble plutôt associée (1) à l’érosion de stocks argileux variés en fonction des fluctuations eustatiques et/ou (2) à la redistribution du matériel détritique le long d’un transect proximal-distal sous l’effet de processus de tri granulométrique. La distribution de la matière organique principalement marine du Dévonien moyen au Carbonifère, montre que les paléoenvironnements étaient favorables à de fortes paléo-productivité de surface probablement associées à une dysoxie/anoxie de toute ou partie de la colonne d’eau, dans un contexte de bassin marin restreint. Les plus fortes valeurs de COT (20 %) mesurées dans la coupe de Kiya (Famennien) sont pourraient être associées à un des OAEs majeurs du Dévonien, l’évènement Hangenberg, mais la précision des données biostratigraphiques disponibles ne permet pas de l’assurer. Quoi qu’il en soit, les OAE qui se succèdent au Dévonien auraient pu favoriser l’accumulation et la préservation de la matière organique dans le Dévonien du Mougodjar, en plus des facteurs physiographiques (restriction du bassin vers le sud). Les fortes concentrations en carbone organique (COT 20%) des sédiments dévoniens montrent de bonnes roches mères potentielles. Les teneurs en carbone organique, surtout d’origine terrestre, des sédiments turbiditiques permiens sont plus faibles (COT pouvant cependant atteindre 4%) mais assez élevées dans certains niveaux stratigraphiques. Les faciès silto-sableux proximaux ont livré les plus fortes concentrations en COT. Ces turbidites permiennes ont des caractéristiques de réservoirs. Elles peuvent aussi se révéler de roches-mères gas-prone potentielles. L’interprétation des données de sub-surface nous a permis de préciser la structure du bassin d’avant-pays à l’échelle de l’Oural méridional. Il est constitué de plis et de chevauchements à vergence est qui résultent d’une évolution polyphasée. Les plis s’amortissent vers l’ouest et passent à la partie peu déformée du bassin puis à la plate-forme. A partir de ces données nous avons reconstruit des schémas d’évolution tectono-sédimentaire et des cartes paléogéographiques de la partie occidentale du Mougodjar. / This thesis is dedicated to the study of the foreland basin of southern Ural in Kazakhstan (Mougodjar). Sedimentological data have been collected from field investigations, and sub-surface data (seismic profiles, wells) have been studied. A sedimentological investigation of the turbidites, Carboniferous to Early Permian in age, has been performed. It allowed to characterize the environments of deposition of the turbidites and to evidence the long-term succession from uppermost Carboniferous to early Permian. The analysis of turbides indicates that the long-term sequences are controlled by global sea-level changes controlled by glacio-eustatism. The Early Permian orogeny, associated to the uplift of the Ural chain, controlled the quantity and quality of the sedimentary input sourcing the foreland basin. Important variations in the conglomeratic levels reflect (1) the erosion of material from the volcanic arc and carbonate platforms constituting the margins of the basin, and (2) local reorganizations of sub-marine slopes (changes in paleo-current directions). The smectitic minerals are the most frequent in the clay minerals assemblages reported in the uppermost Carboniferous to Early Permian sequences. Illite, Kaolinite, and chlorite are less frequently observed. This assemblage of clay minerals shows a permanence of detrital sources filling the basin. This pattern is thought to reflect a sorting effect of the clay particles along a proximal-distal transect, either than a direct paleoclimatic control. The distribution of the organic matter, mainly marine from the Middle Devonian to the Carboniferous indicates that the paleoenvironments were looked favourable to high surface paleoproductivities associated to a dysoxy/anoxy of all, or part, of the water column in the context of a restricted marine basin. The highest values of COT (20 %) found in the Kiya section (Fammenian) may be associated to a major Devonian OAE, the Hangenberg event. However, the accuracy of available biostratigraphic data does not allow to ensure such correlation. Indeed, OAE events may have favoured the accumulation and preservation of the organic matter in the Mougodjar, in addition to physiographical effects (e.g., the relative closure of the basin toward the south). The high concentration in organic carbon (COT 20%) of the Devonian sediments shows good potential source rocks. The content in organic matter, mainly from terrestrial origin, of the Permian turbidites are lower (COT reaching up to 4%), but quite high in some stratigraphic levels. The proximal silty-sandy deposits display the higher COT values. These Permian turbidites may be good reservoirs. They could also be potential gas-prone source rocks. The study of the sub-surface data allowed us to determine the structure of the foreland basin at the scale of southern Ural. It is constituted of folds and west-vergent thrusts resulting from a polyphased tectonic evolution. The folds gradually disappear toward the west passing westward either to the stable Russian platform in the north or to the eastern Pre-Caspian basin to the south. We have reconstructed the tectono-sedimentary evolution of the western Mougodjar through paleogeographic maps. Five key periods have been selected between the Devonian to early Permian period. Our reconstructions evidence two main orogenic events: (1) a first collision between the European continent and the Magnitogorsk volcanic arc in Middle Devonian, and (2) the major uralian orogeny during the Late Carboniferous to Early Permian times resulting from the collision of the European continent with the Kazakh and Siberian plates. This event originated the foreland basin, which is almost completely fulfilled by a thick detrital sequence. In Kungurian, the foreland basin is almost completely isolated and a thick evaporitic sequence deposited.
9

Evaluation of two word alignment systems

Wang, Xiaoyang January 2004 (has links)
<p>This project evaluates two different systems that generate wordalignments on English-Swedish data. The systems to be used are the Giza++ system, that may generate a variety of statistical translation models, and I*Trix system developed at IDA/NLPLab that generates word pairs with frequencies. </p><p>The file formats of these two systems, the way of running them and the differences of the two systems are addressed in this paper. Evaluation in this project considers a variety of parameters such as corpus size, characteristics of the corpus, the effect of linguistic knowledge, etc. At the end of this paper, the conclusions of the two systems evaluation are presented. In general, Giza++ is better applying on big corpora while I*Trix is better for small corpora. Especially for corpora with high statistical ratio or special resource, I*Trix has a better performance.</p>
10

Automatisk FAQ med Latent Semantisk Analys

Larsson, Patrik January 2009 (has links)
<p>I denna uppsats presenteras teknik för att automatiskt besvara frågor skrivna i naturligt språk, givet att man har tillgång till en samling tidigare ställda frågor och deras respektive svar.</p><p>Jag bygger ett prototypsystem som utgår från en databas med epost-konversationer från HP Help Desk. Systemet kombinerar Latent Semantisk Analys med en täthetsbaserad klustringsalgoritm och en enkel klassificeringsalgoritm för att identifiera frekventa svar och besvara nya frågor.</p><p>De automatgenererade svaren utvärderas automatiskt och resultaten jämförs med de som tidigare presenterats för samma datamängd. Inverkan av olika parametrar studeras också i detalj.</p><p>Studien visar att detta tillvägagångssätt ger goda resultat, utan att man behöver utföra någon som helst lingvistisk förbearbetning.</p>

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