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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

Das Rathaus in Marl zur Bedeutung der Architektur für die politische Sinnstiftung auf kommunaler Ebene /

Kleineschulte, Stefan. January 2003 (has links) (PDF)
Bochum, Universiẗat, Diss., 2003.
2

Παράμετροι διατμητικής αντοχής για τους κατώτερους Μαργαϊκούς ορίζοντες του Νομού Αχαΐας / Parameters of shear strenght for the lower marl horizons of the county of Achaia

Τσάντζαλος, Γεώργιος 28 June 2007 (has links)
Στην διατριβή αυτή έχουμε ως σκοπό την μελέτη των φυσικών και μηχανικών ιδιοτήτων του κατώτερου μαργαϊκού ορίζοντα του Νομού Αχαϊας καθως και την παράθεση των συσχετίσεων που υπάρχουν μεταξύ αυτών. / In this paper we intent to study the physical and mechanical characteristics of the lower marl horizontal of the county of Achaia. In addition we have the quotation of any connection which possibly arise among them.
3

Potential rates of methanogenesis in peat and marl sawgrass wetlands in the Florida Everglades

Bachoon, Dave S. 14 September 1990 (has links)
Methanogenesis was studied in soils from two sawgrass wetlands of the Florida Everglades. Marl soils exhibited a significantly higher potential rate of methanogenesis than peat soils. In these wetlands, methanogenesis: (1) decreased rapidly with increasing soil depth, (2) increased at higher temperatures and lower Eh, (3) was stimulated by organic compounds (cellulose, glucose and acetate), and (4) remained unaffected by added ammonium. Lowering the Eh in the peat and marl soils with sulfide or sulfate stimulated methanogenesis. In January 1990, phosphate caused a significant increase in methanogenesis. The potential rates of methanogenesis decreased to undetectable levels when water levels dropped below the surface, and peaked one month after the start of the wet season. Methanogenesis appeared to be a relatively important process in carbon cycling in marl soils and these soils do not accumulate peat. Therefore, one possible explanation for peat accumulation in sawgrass wetlands may be their low rates of methanogenesis.
4

Παράμετροι διατμητικής αντοχής στους ανώτερους Μαργαϊκούς ορίζοντες του Νομού Αχαΐας / Soil strength parameters of “Upper Marl Formations” at Achaia prefecture

Κουλούρης, Σπυρίδων 28 June 2007 (has links)
Στην εργασία αυτή αρχικά πραγματοποιείται μια σύντομη περιγραφή της γεωλογίας του νομού Αχαΐας με παράθεση στοιχείων της σεισμικότητάς της ευρύτερης περιοχής καθώς και παράθεση υδρομετεωρολογικών στοιχείων. Η σπουδαιότητα των στοιχείων αυτών έγκειται στην κατανόηση του ευρύτερου γεωλογικού περιβάλλοντος στο οποίο ανήκουν και οι σχηματισμοί των οποίων οι ιδιότητες διερευνήθηκαν. Ακολουθεί η περιγραφή των εργαστηριακών δοκιμών που εκτελέστηκαν, σύμφωνα με τις προδιαγραφές της ισχύουσας νομοθεσίας αλλά και της διεθνούς πρακτικής. Στη συνέχεια σχολιάζονται θέματα σχετικά με την δειγματοληψία και την περιγραφή των γεωλογικών σχηματισμών που απασχολούν την εργασία αυτή. Παρουσιάζονται αναλυτικά ο τρόπος και οι θέσεις λήψεως δειγμάτων, ενώ παρέχονται και στοιχεία από τη γεωλογία της εκάστοτε περιοχής σε μια προσπάθεια να συγκεντρωθούν κατά το δυνατόν περισσότερα δεδομένα που συσχετίζονται με τους εδαφικούς σχηματισμούς που μελετήθηκαν. Δίνονται, τέλος, τα αποτελέσματα των εργαστηριακών δοκιμών και παρουσιάζονται τα συμπεράσματα που προέκυψαν, ενώ παρατίθενται και τα πλήρη στοιχεία που αφορούν στην εκτέλεσή τους. Στα πλαίσια του στόχου της πλήρους ανάλυσης και της απόδοσης μιας ολοκληρωμένης εικόνας των σχηματισμών, εκτελέστηκαν, πλέον των εργαστηριακών δοκιμών προσδιορισμού των παραμέτρων διατμητικής αντοχής και δοκιμές προσδιορισμού των αντίστοιχων παραμέτρων που σχετίζονται με τις φυσικές τους ιδιότητες. Με τα στοιχεία που προέκυψαν έγινε μια απόπειρα συσχετισμού των μεγεθών μεταξύ τους, ώστε να διαφανούν πιθανές εξαρτήσεις και να εξηγηθούν διαφοροποιήσεις στα αποτελέσματα των δοκιμών. / In this essay there is initially presented a short description of the geology of prefecture Achaia with apposition of data of it’s wider region seismicity as well as apposition of hydrometeorological data. The importance of presenting this data lies in the comprehension of the wider geological environment in which the formations of this work’s interest belong. Then there follows the description of laboratorial tests that were executed, according to the specifications as presented in effect legislation but also set by international practice. There are also presented subjects with regard to the sampling methods and the description of geological formations that occupy this work’s area of interest. There are analytically presented the way and the sites of reception of samples, while there is also analyzed information regarding to the geology of each site in order to collect as much data connected to the soils that were studied as possible. There are finally presented the results of laboratorial tests (and also the conclusions that resulted). In the objective of complete analysis and the understanding of the marl-type soils that were investigated, along with the elements that resulted, there was an attempt of correlation between shear strength parameters and soil properties, so that should emerge likely dependences and would be explained differentiations in the results of laboratory testing.
5

Dewatering Plan And Prediction For Pit Lake Flooding For A Quarry Site

Duru, Uygar 01 April 2004 (has links) (PDF)
This study presents the dewatering assessment of a marl quarry with the future pit lake level predictions. The objectives of the study were / (1) to determine the dewatering requirements that would allow for the continuation of the quarrying operations in the deeper parts of the quarry, (2) to design an optimum dewatering system compatible with the site hydrogeological conditions and quarrying plans, (3) to assess the environmental impacts of dewatering on the local water (surface and ground water) resources and users, and (4) to predict the future pit lake level and flooding period for different meteorological conditions. To these ends, previous investigation reports and maps have been compiled and reviewed and field investigations have been conducted. During the field investigations pumping and observation wells were drilled and installed. After installation, in situ tests were conducted to determine aquifer parameters. It was found that properties of the material is conducive to the dewatering activities that will be necessary for the deepening of the open pit of the marl quarry. A groundwater model was developed based on the field data gathered. According to this model dewatering trenches will be needed to dewater the pit. The model predicted that operating these dewatering trenches would create an elongated cone of depression that will sufficiently lower the groundwater table so that quarrying operations can proceed. Lowering of the water table may produce a negative impact on groundwater resources within the aerial extent of the cone of depression. This potentially negative impact was investigated with model simulations and has been found that the impact to the resources would be negligible. Three scenarios were evaluated as possible dewatering discharge disposal solutions. The preferred scenario included the discharge of this water to the stream, which is flowing on the western side of the quarry. The pit will start to fill with water immediately after the dewatering operations stopped. In order to predict the pit lake flooding period and final lake elevation, pit lake hydrologic model was developed. The simulations predict that the final pit lake elevation would be at 991 m. The pit lake will rise to this level at approximately 72 years after closure.
6

Insights into the Early Transgressive History of Lake Bonneville from Stratigraphic Investigation of Pilot Valley Playa, UT/NV, USA

Rey, Kevin A. 30 October 2012 (has links) (PDF)
Multiple shallow sediment cores were obtained from Pilot Valley playa, a sub-basin located in the northwestern Bonneville basin. Analysis of stratigraphy, ostracodes, mineralogy, chemistry, total inorganic carbon (TIC), total organic carbon (TOC), and stable isotopes were performed to better place these sediments into proper context with respect to the Lake Bonneville cycle. Results showed Pilot Valley playa contains a nearly full sequence of Lake Bonneville deep-water marl in addition to sediments deposited before and after the Lake Bonneville cycle. Within the marl is a sequence of organic rich algal laminated marl correlated with the Stansbury oscillation. Four 14C ages ranging from ~22.4 k 14C years to ~15.8 k 14C years from preserved algae filaments in this sequence place it well within the time frame of the Stansbury oscillation. Oolitic sand found below this sequence indicates the existence of a shallow (<~5 m), saline lake in Pilot Valley prior to the transgression of Lake Bonneville. Analysis of sediments deposited during the late regressive phase of Lake Bonneville indicates the lake may have fallen to levels below that of Pilot Valley prior to transgressing to the Gilbert level.
7

Decentralized Integration of Distributed Energy Resources into Energy Markets with Physical Constraints

Chen Feng (18556528) 29 May 2024 (has links)
<p dir="ltr">With the growing installation of distributed energy resources (DERs) at homes, more residential households are able to reduce the overall energy cost by storing unused energy in the storage battery when there is abundant renewable energy generation, and using the stored energy when there is insufficient renewable energy generation and high demand. It could be even more economical for the household if energy can be traded and shared among neighboring households. Despite the great economic benefit of DERs, they could also make it more challenging to ensure the stability of the grid due to the decentralization of agents' activities.</p><p><br></p><p dir="ltr">This thesis presents two approaches that combine market and control mechanisms to address these challenges. In the first work, we focus on the integration of DERs into local energy markets. We introduce a peer-to-peer (P2P) local energy market and propose a consensus multi-agent reinforcement learning (MARL) framework, which allows agents to develop strategies for trading and decentralized voltage control within the P2P market. It is compared to both the fully decentralized and centralized training & decentralized execution (CTDE) framework. Numerical results reveal that under each framework, the system is able to converge to a dynamic balance with the guarantee of system stability as each agent gradually learns the approximately optimal strategy. Theoretical results also prove the convergence of the consensus MARL algorithm under certain conditions.</p><p dir="ltr">In the second work, we introduce a mean-field game framework for the integration of DERs into wholesale energy markets. This framework helps DER owners automatically learn optimal decision policies in response to market price fluctuations and their own variable renewable energy outputs. We prove the existence of a mean-field equilibrium (MFE) for the wholesale energy market, and we develop a heuristic decentralized mean-field learning algorithm to converge to an MFE, taking into consideration the demand/supply shock and flexible demand. Our numerical experiments point to convergence to an MFE and show that our framework effectively reduces peak load and price fluctuations, especially during exogenous demand or supply shocks.</p>
8

La résolution des litiges sportifs / Sport disputes resolution

Le Reste, Simon 18 December 2015 (has links)
La résolution des litiges sportifs a démontré une extraordinaire vivacité ces vingt-cinq dernières années avec la mise en jeu de trois grandes formes de justice qui constituent les « justices sportives », à savoir la justice interne des organisations sportives (disciplinaire et administrative), la justice alternative (MARL, arbitrage et autorités indépendantes) et la justice étatique (française et européenne). A travers le dialogue des différents juges du sport, ces trois justices, pourtant si différentes, s’éclairent, se tolèrent, se respectent et se complètent, permettant ainsi une résolution cohérente et efficace des litiges sportifs. La présente étude visera aussi à mettre en lumière l’existence d’un dialogue entre les différents juges du sport. Ce dialogue participe à l’amélioration de la résolution des litiges sportifs et plus généralement des normes sportives. A travers le dialogue des juges, la justice interne des organisations sportives a considérablement évolué au plus grand profit des justiciables du mouvement sportif qui y ont trouvé des droits plus fermes et mieux garantis. Parallèlement, et tirant bénéfice là encore du dialogue des juges, la justice alternative a connu un développement remarquable, prouvant sa très grande efficacité dans la résolution des litiges sportifs. Reste que ces deux justices ne peuvent raisonnablement prétendre couvrir l’ensemble des litiges du sport et leur donner une issue définitive. En dépit des progrès de la justice sportive interne des organisations sportives, et malgré le développement de la justice alternative, l'intervention de la justice étatique demeure indispensable dans la bonne résolution des litiges sportifs / Sport disputes resolution has shown an extraordinary strength over the past twenty-five years through the interaction between the three main forms of justice as component of the "sport justices", i.e. the internal justice of the sport organisations (disciplinary and administrative justice), the alternative justice (ADR, arbitration and independent authorities) and the state justice (French and European justice).Through the dialogue between the various sport judges, we will also analyze how these three justices, despite their differences, enlighten each other, stand each other, respect and complete each other. This research also aims at highlighting the very existence of the dialogue between the different sport judges. This dialogue plays a part in the improving of sport disputes resolution and more generally of the sport rules.Through the dialogue of judges, the internal justice of the sport organisations has significantly changes to the benefit of the members of sport organsisations whose rights are more guaranteed. Alongside, thanks to the dialogue between judges, the development of the alternative justice is considerable, showing its significant efficiency in sport disputes resolution. Nonetheless, these two justices cannot pretend covering the whole sport litigation and handing down final and binding decisions. Despite the positive evolution of the internal justice of sport organisations and the development of the alternative justice, the involvement of the state justice remains indispensable in the good resolution of sport litigation.
9

Late-glacial to holocene climate variability in western Ireland

Diefendorf, Aaron F. 22 April 2005
Increasing concerns over future anthropogenic effects on climate change as a result of increasing greenhouse gases generate concomitant efforts to better characterize recent climate in order to more accurately predict climate in the future. To this end, a multiproxy study of climate variability in western Ireland from lacustrine sediment was undertaken. The interpretation of paleoclimate records derived from lacustrine carbonate minerals is difficult without a good understanding of the mechanisms that generate variation in isotope values of modern surface waters. Variation in surface waters are ultimately incorporated into lacustrine sediment records conflated by temperature. Therefore, a study of the spatial distribution of ä<sup>18</sup>O and äD values of lake and river waters from 144 locations in Ireland has been conducted to provide insight into the behavior of lakes and rivers in Ireland, including source, recycling and loss through evapotranspiration. A 7.6 m sediment core was recovered from Lough Inchiquin that provides evidence for rapid and long-term climate change from the Late Glacial to the Holocene. This was determined using carbon and oxygen isotope analyses of lacustrine calcite as well as carbon from bulk organic sediment fractions. Several significant climate perturbations were identified in the ä<sup>18</sup>O<sub>calcite</sub> record such as the Oldest Dryas, Younger Dryas, and the 8.2 ka cold event. A previously undescribed climate anomaly between 7,300 to 6,700 cal. yr B.P. characterized by low ä<sup>18</sup>O</span><sub>calcite</sub> values with high frequency variability. Variations in carbon isotopes of calcite and bulk organics from the Late Glacial to the Holocene are significant in magnitude (~12) and have similar trends that record temporal shifts in the relative contributions of carbon from the weathering of limestone versus the weathering of terrestrial organic matter. ä<sup>13</sup>C<sub>calcite</sub> and ä<sup>13</sup>C<sub>org</sub> suggest a rapid recovery of terrestrial vegetation following the Younger Dryas. Change in Ää<sup>13</sup>C<sub>calcite - org</sub> documents a rapid increase in exogenous fluxes of carbon into the lake at ~9 ka.
10

Late-glacial to holocene climate variability in western Ireland

Diefendorf, Aaron F. 22 April 2005 (has links)
Increasing concerns over future anthropogenic effects on climate change as a result of increasing greenhouse gases generate concomitant efforts to better characterize recent climate in order to more accurately predict climate in the future. To this end, a multiproxy study of climate variability in western Ireland from lacustrine sediment was undertaken. The interpretation of paleoclimate records derived from lacustrine carbonate minerals is difficult without a good understanding of the mechanisms that generate variation in isotope values of modern surface waters. Variation in surface waters are ultimately incorporated into lacustrine sediment records conflated by temperature. Therefore, a study of the spatial distribution of ä<sup>18</sup>O and äD values of lake and river waters from 144 locations in Ireland has been conducted to provide insight into the behavior of lakes and rivers in Ireland, including source, recycling and loss through evapotranspiration. A 7.6 m sediment core was recovered from Lough Inchiquin that provides evidence for rapid and long-term climate change from the Late Glacial to the Holocene. This was determined using carbon and oxygen isotope analyses of lacustrine calcite as well as carbon from bulk organic sediment fractions. Several significant climate perturbations were identified in the ä<sup>18</sup>O<sub>calcite</sub> record such as the Oldest Dryas, Younger Dryas, and the 8.2 ka cold event. A previously undescribed climate anomaly between 7,300 to 6,700 cal. yr B.P. characterized by low ä<sup>18</sup>O</span><sub>calcite</sub> values with high frequency variability. Variations in carbon isotopes of calcite and bulk organics from the Late Glacial to the Holocene are significant in magnitude (~12) and have similar trends that record temporal shifts in the relative contributions of carbon from the weathering of limestone versus the weathering of terrestrial organic matter. ä<sup>13</sup>C<sub>calcite</sub> and ä<sup>13</sup>C<sub>org</sub> suggest a rapid recovery of terrestrial vegetation following the Younger Dryas. Change in Ää<sup>13</sup>C<sub>calcite - org</sub> documents a rapid increase in exogenous fluxes of carbon into the lake at ~9 ka.

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