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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.
571

Analýza kostry synchronního generátoru / The analysis of frame synchronous generator

Marada, Ondřej January 2011 (has links)
The thesis is focused on the examination of the utility of a synchronous generator of a small hydroelectric power station in the case of a change of working position of the machine. The utility will be measured on the basis of the examination of deformations and state of stress of the frame of the generator for the present running (with vertical axis of rotation of the generator) and subsequently for modified running (with horizontal axis of rotation). This will be accomplished partly on the static shell model by finite element method and consequently on the simplified dynamic model.
572

Effects of hydro-meteorological variables, soil physical properties, topography and land use on unsaturated zone soil moisture in Siloam Village, South Africa

Nndwammbi, E. M. 10 February 2016 (has links)
MESCH / Department of Hydrology and Water Resources
573

Radium- und Radon-Isotopen-Untersuchungen als Hilfsmittel für die Aquiferdiagnose unter besonderer Berücksichtigung der geochemischen und hydrochemischen Verhältnisse im Grundwasserleiter

Hurst, Stephanie 12 December 2014 (has links)
Zielsetzung der Arbeit war vorrangig die Entwicklung bzw. Weiterentwicklung von Methoden zur verbesserten Interpretation der hydraulischen Gegebenheiten in einem Grundwasserleiter mit Hilfe der Bestimmung von Radiumisotopenverhältnissen im Verlauf von Pumpversuchen. Daneben wurden 222Rn/226Ra-Verhältnisse betrachtet und interpretiert. Des Weiteren wurden Gesteinsuntersuchungen durchgeführt sowie Untersuchungen an Gesteinsoberflächen (Sekundärminerale) um Aussagen über das Löslichkeitsverhalten bzw. die Mobilität von Radium im Grundwasser zu erhalten. Die Grundwasser- und Gesteinsproben stammten vor allem aus dem Umfeld der kontinentalen Tiefbohrung (KTB Oberpfalz) sowie aus der Vorbohrung zur KTB, aber auch aus benachbarten Bundesländern und der Tschechischen Republik (Egergraben). Im Ergebnis zeigte sich, dass sich die Untersuchung der Isotopenverhältnisse zur vertiefenden Aquiferdiagnose gut eignet. Die geochemischen Untersuchungen erlaubten einen Einblick in das Löslichkeitsverhalten der untersuchten Radionuklide.:LISTE DES ABKÜRZUNGEN 12 LISTE DER TABELLEN 17 1. EINLEITUNG - BISHERIGE ARBEITEN 23 1.1 ZIELSETZUNG 23 1.2 BISHERIGE ARBEITEN ZU RADIUM UND RADON 25 2. RADIUM UND RADON: GRUNDLAGEN 27 2.1 ENTSTEHUNG UND VORKOMMEN 27 2.1.1 VORKOMMEN IN DER LITHOSPHÄRE 27 2.1.2 VORKOMMEN IN DER HYDROSPHÄRE 29 2.2 PHYSIKALISCHE UND CHEMISCHE EIGENSCHAFTEN 31 2.2.1 RADIOAKTIVITÄT 31 2.2.2 CHEMISCHE UND PHYSIKALISCHE EIGENSCHAFTEN VON RADIUM 32 2.2.3 CHEMISCHE UND PHYSIKALISCHE EIGENSCHAFTEN VON RADON 33 2.3 DAS VERHALTEN VON RADON UND RADIUM IM GRUNDWASSERLEITER 34 2.3.1 DAS VERHALTEN VON RADON 34 2.3.2 GEOCHEMIE UND HYDROCHEMIE DES RADIUMS 35 2.3.3 VERHALTEN VON RADIUM BEI ANWESENHEIT VON KOLLOIDEN UND TONMINERALEN 37 2.3.4 STOFFTRANSPORT UND ADSORPTION 38 2.3.5 DAS VERHALTEN VON RADIUM BEI ANWESENHEIT VON EISEN UND MANGAN 41 2.3.5.1 HYDROLYSE DES EISEN-III 42 2.3.5.2 BILDUNG VON EISENHYDROXIDNIEDERSCHLÄGEN AUF GESTEINSOBERFLÄCHEN UND IHRE ALTERATION 42 2.3.5.3 PARAMETER WELCHE DIE HYDROLYSE, DIE BILDUNG VON NIEDERSCHLÄGEN UND DIE ALTERATION BEEINFLUSSEN 43 2.3.5.4 RADIUM-ADSORPTION AN EISEN- UND MANGANHYDROXIDE 45 3. DIE RADIUM-ISOTOPENVERHÄLTNIS-METHODE ALS HILFSMITTEL FÜR DIE AQUIFERDIAGNOSE 47 3.1 GRUNDLAGEN DER HYDRAULIK 47 3.1.1 PERMEABILITÄT (K) 47 3.1.2 WEITERE HYDRAULISCHE PARAMETER 48 3.2 HYDRAULISCHE METHODEN FÜR DIE AQUIFERDIAGNOSE 49 3.2.1 PUMPVERSUCHE 50 3.2.1.1 DATENERHEBUNG 50 3.2.1.2 AUSWERTUNG 50 3.3 VERÄNDERUNG VON RADIUM- UND RADONISOTOPENVERHÄLTNISSEN IM VERLAUF VON PUMPVERSUCHEN ALS INDIKATOREN FÜR FLIEßVERHALTEN UND MISCHUNG VERSCHIEDEN MARKIERTER GRUNDWÄSSER 52 3.3.1 THEORIEN ZU DEN RADIUM-ISOTOPENVERHÄLTNIS-METHODEN 52 3.3.1.1 EINSCHÄTZUNG DER RELATIVEN FLIEßGESCHWINDIGKEIT - FLIEßZEITMODELL - 53 3.3.1.2 EINSCHÄTZUNG DER ZUMISCHUNG EINES FREMDEN SYSTEMS - MISCHMODELLE - 57 3.3.1.3 UNTERSCHEIDUNG VON DOPPELPOROSITÄT, LEAKAGE UND SCHEINBARER DOPPELPOROSITÄT - DOPPELPOROSITÄTSMODELL - 58 3.3.1.4 METHODE ZUM NACHWEIS ANTHROPOGENER RADIONUKLIDE IM GRUNDWASSER - KONTAMINATIONSMODELL - 60 3.3.1.5 ÄNDERUNG DES 222RN/226RA-VERHÄLTNISSES - REDOXMODELL - 60 3.3.1.6 ÄNDERUNG DES 222RN-GEHALTES - DRUCKÄNDERUNGSMODELL - 61 4. PROBENAHME, PRÄPARATION UND ANALYSE VON WASSERPROBEN 63 4.1 RADIUM IN GRUNDWASSERPROBEN 63 4.1.1 PROBENAHME 63 4.1.2 PRÄPARATION 63 4.1.3 MESSUNG 63 4.2 RADON IN GRUNDWASSERPROBEN 64 4.2.1 PROBENAHME 64 4.2.2 PRÄPARATION 64 4.2.3 MESSUNG 64 5. ERGEBNISSE UND DISKUSSION DER RA- UND RN- ISOTOPEN-UNTERSUCHUNGEN UNTER BERÜCKSICHTIGUNG DER GEOLOGIE, DER WASSERCHEMIE UND DER KONVENTIONELLEN ISOTOPENUNTERSUCHUNGEN (3H, 2H, 18O, 13C, 14C) 65 5.1. GEOLOGIE DES BEREICHES DER KTB UND DES KTB-UMFELDES 65 5.2 AUSWERTUNG DER CHEMISCHEN UND RADIOMETRISCHEN UNTERSUCHUNGEN VON EINZELPROBEN VON GRUNDWÄSSERN VERSCHIEDENER REGIONEN 67 5.2.1 RELATION ZWISCHEN DEN SPEZIFISCHEN ELEKTRISCHEN LEITFÄHIGKEITEN UND DEN RADIUM-AKTIVITÄTEN 68 5.2.2 RELATION ZWISCHEN DEN CHLORID-GEHALTEN UND DEN RADIUM-AKTIVITÄTEN 71 5.2.3 RELATION ZWISCHEN DEN SULFAT-GEHALTEN UND RADIUM-AKTIVITÄTEN 72 5.2.4 RELATION ZWISCHEN DEN BARIUM- UND STRONTIUM-GEHALTEN SOWIE DEN EISEN- UND MANGAN-GEHALTEN UND DEN RADIUM-AKTIVITÄTEN 72 5.2.5 RELATION ZWISCHEN DEN PH-WERTEN UND DEN RADIUM-AKTIVITÄTEN 75 5.2.6 RELATION ZWISCHEN DEN REDOX-POTENTIALEN UND DEN RADIUM-AKTIVITÄTEN 78 5.2.7 RADONAKTIVITÄTEN IN RELATION ZU RADIUMAKTIVITÄTEN UND ENTNAHMETIEFEN SOWIE RADIUMAKTIVITÄTEN IN RELATION ZU DEN VERWEILZEITEN DES GRUNDWASSERS, 226RA/228RA-VERHÄLTNISSE 78 5.2.8 DISKUSSION EINZELNER UNTERSUCHUNGSGEBIETE 84 5.2.8.1 KTB-UMFELD 84 5.2.8.2 SÜDSCHWARZWALD - HERKUNFT DES RADIUMS 85 5.2.8.3 MYDLOVARY (ČR) - ANWENDUNG DES KONTAMINATIONSMODELLS 86 5.3 UNTERSUCHUNGEN AN FLUID- UND GESTEINSPROBEN AUS DER KTB-VB UND AN FLUIDPROBEN DER KTB-HB 88 5.3.1 PUMPVERSUCH APRIL 1990 AN DER KTB-VB 89 5.3.1.1 RADIUM-AKTIVITÄTEN DER FLUIDPROBEN 90 5.3.2 PUMPVERSUCH AUGUST BIS DEZEMBER 1991 AN DER KTB-VB 91 5.3.3 RADONAKTIVITÄTEN VON FLUID- UND GASPROBEN AUS DER KTB-VB 93 5.3.4 RELATION DER RA-AKTIVITÄTEN DER FLUIDE ZU DENEN DES GESTEINS DER KTB-VB 94 5.3.5 UNTERSUCHUNGEN AN FLUIDEN DER KTB-HB 95 5.4 PUMPVERSUCHE IM NÄHEREN KTB-UMFELD 96 5.4.1 PUMPVERSUCHE IN EINEM GRANIT-/DIABAS-GRUNDWASSERLEITER 96 5.4.1.1 PECHBRUNN SILVANA I 96 5.4.1.2 PECHBRUNN SILVANA II 99 5.4.1.3 ZUSAMMENFASSENDE BEURTEILUNG DER GRUNDWÄSSER AUS SILVANA I UND II 101 5.4.2 PUMPVERSUCH IN EINER TIEFBOHRUNG IM EGERGRABEN UND VERGLEICHENDE UNTERSUCHUNG DES GRUNDWASSERS AUS EINER THERMALQUELLE: KARLOVY VARY (KARLSBAD, ČR) 102 5.4.2.1 EINFÜHRUNG UND BESCHREIBUNG DER PROBENAHMESTELLEN 102 5.4.2.2 VERLAUF DES PUMPVERSUCHS IN DER BOHRUNG HJ-2 103 5.4.2.3 CHEMISCHE ZUSAMMENSETZUNG DER FLUIDE 104 5.4.2.4 ERGEBNISSE DER RADIUM- UND RADONISOTOPENUNTERSUCHUNGEN UNTER BERÜCKSICHTIGUNG DER ISOTOPENHYDROLOGISCHEN UNTERSUCHUNGEN 106 5.4.2.5 ERGEBNISSE DER GASANALYSEN 109 5.4.2.6 ZUSAMMENFASSUNG DER ERGEBNISSE UND DARAUS ABGELEITETE FOLGERUNGEN 110 5.4.3 PUMPVERSUCH IN KELLERHAUS NE` MANTEL (OBERPFALZ) 111 5.5 PUMPVERSUCHE IM WEITEREN KTB-UMFELD 113 5.5.1 PUMPVERSUCH IM OBEREN BUNTSANDSTEIN (RHÖT) UNTERFRANKENS: WIESENFELD BEI KARLSTADT 113 5.5.1.1 ERGEBNISSE DER VOR-ORT-MESSUNGEN UND DER HYDROCHEMISCHEN UNTERSUCHUNGEN 113 5.5.1.2 ERGEBNISSE DER ISOTOPENUNTERSUCHUNGEN 114 5.5.1.3 ERGEBNISSE DER RADIUM-UNTERSUCHUNGEN UND INTERPRETATION 114 5.5.2 PUMPVERSUCH IM UNTEREN KEUPER/BENKER SANDSTEIN OBERFRANKENS: NEUHAIDHOF BEI CREUSSEN 117 5.5.2.1 ERGEBNISSE DER VOR-ORT-MESSUNGEN UND WASSERCHEMIE 118 5.5.2.2 ERGEBNISSE DER TRITIUMUNTERSUCHUNGEN 118 5.5.2.3 ERGEBNISSE DER RADIUM- UND RADON-AKTIVITÄTSBESTIMMUNGEN 118 5.5.3 PUMPVERSUCH IN EINEM GRUNDWASSERLEITER DES MITTLEREN KEUPER: THERMALBOHRUNG BAYREUTH/OBERFRANKEN 120 5.5.3.1 ERGEBNISSE DER ISOTOPENUNTERSUCHUNGEN 120 5.5.3.2 ERGEBNISSE DER GASGEHALTSBESTIMMUNGEN 122 5.5.3.3 ERGEBNISSE DER RADIUM- UND RADON-AKTIVITÄTSBESTIMMUNGEN 123 5.5.4 PUMPVERSUCH IM MITTLEREN KEUPER/BURGSANDSTEIN: ECKERSDORF/OBERFRANKEN 123 5.5.4.1 ERGEBNISSE DER VOR-ORT-MESSUNGEN 125 5.5.4.2 ERGEBNISSE DER ISOTOPENUNTERSUCHUNGEN 125 5.5.4.3 ERGEBNISSE DER RADIUM- UND RADON-AKTIVITÄTSBESTIMMUNGEN 125 5.5.5 PUMPVERSUCH IM MUSCHELKALK UND ROTLIEGENDEN DER BOHRUNG TREUCHTLINGEN T2 126 5.5.5.1 ERGEBNISSE DER RADIUM-AKTIVITÄTSBESTIMMUNGEN 128 5.6 PUMPVERSUCHE IN BADEN-WÜRTTEMBERG 128 5.6.1 DREI HORIZONTIERTE PUMPVERSUCHE IN EINER OPALINUSTON-BOHRUNG IN WÜRTTEMBERG (GEISINGEN) 128 5.6.1.1 ERGEBNISSE DER VOR-ORT-MESSUNGEN 130 5.6.1.2 ERGEBNISSE DER ISOTOPENUNTERSUCHUNGEN 130 5.6.1.3 ERGEBNISSE DER RADIUM UND RADON-AKTIVITÄTSBESTIMMUNGEN 132 6. UNTERSUCHUNGEN AN GESTEINSPROBEN 136 6.1 RÖNTGENFLUORESZENZANALYSE (RFA) 136 6.2 PROBENAHME 136 6.3 PRÄPARATION 136 6.4 MESSUNG UND AUSWERTUNG 137 7. ERGEBNISSE UND DISKUSSION DER GESTEINSUNTERSUCHUNGEN 138 7.1 BOHRKERN AUS DER BOHRUNG KARLOVY VARY HJ-2 138 7.1.1 PETROGRAPHISCHE BESCHREIBUNG DER BEARBEITETEN BOHRKERNABSCHNITTE DER BOHRUNG HJ-2 IM EGERGRABEN 138 7.1.1.1 BESCHREIBUNG DER DÜNNSCHLIFFE 141 7.1.1.2 ERGEBNISSE DER RÖNTGENFLUORESZENZANALYSE UND DER KRISTALLWASSER-BESTIMMUNG NACH DER PENFIELD-METHODE 150 7.1.1.3 DISKUSSION DER ERGEBNISSE DER DÜNNSCHLIFF- UND DER RÖNTGENFLOURESZENZANALYSE UNTER BERÜCKSICHTIGUNG DES GRUNDWASSERCHEMISMUS 157 7.1.2 BESTIMMUNG DER 226RA- 228RA- UND 230TH-AKTIVITÄTEN AN GESTEINSPROBEN DER BOHRUNG KARLOVY VARY HJ-2 159 7.1.3 BESTIMMUNG DER Δ18O-WERTE AN GESTEINSPROBEN DER BOHRUNG KARLOVY VARY HJ-2 162 7.1.4 VERGLEICHENDE INTERPRETATION DER GEOCHEMISCHEN, ISOTOPEN-GEOCHEMISCHEN UND RADIOMETRISCHEN ERGEBNISSE 168 7.2 GESTEINSOBERFLÄCHEN 169 7.2.1 BESTIMMUNG DER 238U-GEHALTE, DER 234U/238U- UND 230TH/234U-VERHÄLTNISSE, SOWIE DER 226RA- UND 228RA-AKTIVITÄTEN UND DER 226RA/228RA-VERHÄLTNISSE AN AUSGEWÄHLTEN GESTEINSPROBEN AUS DER BOHRUNG KARLOVY VARY HJ-2 169 7.2.1.1 PRÄPARATION UND LEACHING 169 7.2.1.2 DISKUSSION UND INTERPRETATION DER ERGEBNISSE 173 7.2.2 LEACHING-TESTS AN GESTEINSPROBEN AUS SIBYLLENBAD 174 7.3 RADIUMGEHALTSBESTIMMUNGEN AN VERSCHIEDENEN GESAMTGESTEINSPROBEN 175 8. GEOCHEMISCHE UND RADIOMETRISCHE UNTERSUCHUNGEN AN EISEN- UND MANGAN-OXIHYDROXIDEN 177 8.1 SEQUENTIELLE EXTRAKTION DER EISEN- UND MANGANOXIHYDROXIDE 178 8.1.1 PRÄPARATIONSVERFAHREN 178 8.1.2 ERGEBNISSE DER SEQUENTIELLEN EXTRAKTION 179 8.2 RÖNTGENAUFNAHMEN 180 8.3 ELEKTRONENMIKROSKOPISCHE AUFNAHMEN VERBUNDEN MIT ENERGIEDISPERSIVER RÖNTGENANALYSE EDX 181 8.3.1 PRÄPARATION UND MESSUNG 181 8.3.2 ERGEBNISSE DER ELEKTRONENMIKROSKOPIE UND DER EDX 182 8.4 RÖNTGENFLUORESZENZANALYSEN 184 8.5 ZUSAMMENFASSENDE DISKUSSION DER ERGEBNISSE DER 194 EISEN- UND MANGANOXIHYDROXID-UNTERSUCHUNGEN 194 9. KURZE GESAMTZUSAMMENFASSUNG DER ARBEIT 194 DANK 195 LITERATURVERZEICHNIS 196 VERZEICHNIS DER VERWENDETEN KARTEN 204 ANHANG A: FUßNOTEN 206 ANHANG B: TABELLEN 210 ANHANG C: AUFNAHMEN DER UNTERSUCHTEN BOHRKERNABSCHNITTE DER BOHRUNG KARLOVY VARY HJ 2. 309 ANHANG D: GEOLOGIE DES KTB-UMFELDES (AUS: GEOLOG. KARTE DES KTB-UMFELDES OBERPFALZ 1: 50.000, HANNOVER 1991) 313
574

The Relationship of Weather with Electricity Prices: A Case Study of Albania / Förhållandet mellan Väder och Elpriser: En Fallstudie av Albanien

Greku, Evgjenia, Xie, Zhuohan January 2020 (has links)
Electricity markets may become more sensitive to weather conditions because of higher penetration of renewable energy sources and climatic changes. Albania is 100% reliant on hydropower for its domestic energy generation, making this country compelling to investigate as it is highly sensitive to changing weather conditions. We use an ARMA-GARCH model to investigate whether weather and economic factors had a relationship with monthly hydroelectricity prices in the Albanian Energy Market in the period 2013-2018. We find that electricity price is affected by variations in weather and is not utterly robust to extreme hydrological changes. Generally, our dependent variable appears to be particularly influenced by air pressure followed by temperature and rainfall. We also perceive that there is a relationship between economic factors and hydroelectricity prices, where residual supply appears to have a significant negative relationship with our dependent variable. However, we were originally anticipating a higher dependency of electricity prices on weather conditions, due to the inflated hydro-power reliance for electricity production in the Albanian Energy Market. This effect is offset by several factors, where the state monopolized behaviour of the energy sector occupies a predominant influence on our results.
575

Energy storage and their combination with wind power compared to new nuclear power in Sweden : A review and cost analysis

Englund-Karlsson, Simon January 2020 (has links)
As intermittent renewable energy sources such as wind and solar power gradually increase around the world, older technologies such as nuclear power is phased out in Sweden and many other countries. It is then important to ensure that the total power need is secured, and that the power grid can remain stable. One way of managing intermittent renewables is by using energy storage. The main goal of this thesis was to compare energy storage methods and their costs. A secondary aim was to investigate how the cost of developing more renewable energy sources, in combination with different energy storage methods, compares to erecting new nuclear power. This thesis was limited to three energy storage technologies, namely pumped hydro storage (PHS), compressed air energy storage (CAES), and four battery storage technologies. They were combined with wind power in the cost analysis. The comparison was done by performing a literature review and economical calculations, which focused especially on levelized cost of storage (LCOS). The results from the economic calculations indicated that PHS and CAES had lower LCOS than battery storage technologies. Similar results could be seen in the literature review as well. When comparing levelized cost of energy (LCOE) nuclear power had the lowest, €0.03-0.12 kWh-1, followed by wind power in combination with PHS and CAES, both around €0.07-0.24 kWh-1. This result was maintained also at sensitivity analysis regarding the discount rate, which both nuclear power and PHS proved rather sensitive to. Keywords: energy storage, nuclear power, wind power, pumped hydro storage, compressed air energy storage, battery energy storage, levelized cost of energy, Sweden
576

Etude du comportement hydromécanique des sédiments pollués par les PCB en interaction avec les géomatériaux pour un stockage hors site / Study of the hydromechanical behavior of PCB polluted sediment for a landfill storage

Chahal, Hadi 23 July 2013 (has links)
A l’heure actuelle, des sédiments fluviaux et lacustres se trouvent pollués par les polychlorobiphényles (PCB), à des degrés de gravité divers. Les PCB se présentent comme des micropolluants persistants dans l’environnement et nuisibles à la santé. Un programme de recherche « PCB-Axelera » est conduit afin de pencher sur cette problématique et explorer les solutions de diminution de cette pollution. En France, l'ensemble des arrêtés préfectoraux (30/10/2002 et 14/06/2000) et le décret du 18/04/2002 considèrent les sédiments pollués comme déchets et autorisent leur stockage dans les installations de stockage de déchets si leurs teneurs en PCB sont comprises entre 0,68 ppm et 50 ppm. L’objectif principal de cette étude est de concevoir une méthodologie adaptée pour une installation de déchets non-dangereux ISDND. Les géomatériaux dans ce stockage seront utilisés comme barrière d’étanchéité pour les sédiments pollués. L’étude est composée de trois parties : Dans la première partie la caractérisation hydromécanique chimique des sédiments pollués par les PCB est présentée. La classification des sédiments est effectuée. Le comportement mécanique du sédiment est déterminé à l’aide de l’œdomètre. Quant au comportement hydromécanique il est étudié à l’aide du filtre presse et du perméamètre à paroi rigide (PPR). Cette caractérisation est indispensable pour proposer la meilleure mise en œuvre des sédiments dans le centre de stockage. Dans la deuxième partie, les performances hydraulique (perméabilité) et mécanique (gonflement) des différents géomatériaux en contact avec un fluide extrait du sédiment et d’autres fluides synthétiques contenant des PCB sont explorées. L’étude du gonflement des géomatériaux est réalisée à l’échelle du laboratoire tandis que, l’étude de sa performance hydrique est réalisée sur deux échelles centimétrique et métrique. L’étude menée sur un pilote de 1,2 m3 de volume comprenant un système de pluviation automatique a permis de suivre les tassements à l’aide d’un capteur ultrason et de mesurer la perméabilité des sédiments et des géomatériaux sous conditions réelles de stockage. Dans la troisième partie, un modèle hydraulique 1D est développé afin de suivre le front d’eau au sein d’un échantillon de sédiment soumis à une charge hydraulique représentant l’expérimentation dans un PPR. La méthode VER est utilisée. Les résultats expérimentaux montrent que le degré de contamination en PCB de ces sédiments n’influence pas le comportement hydromécanique et donc la qualité d’étanchéité des géomatériaux étudiés. Les résultats numériques de simulation du comportement hydraulique du sédiment sont en concordance avec les résultats expérimentaux. La solution de stockage hors site des sédiments pollués est alors envisageable puisqu’elle confine la pollution en éliminant le risque de contamination du milieu environnant. / Currently, river and lake sediments are contaminated with polychlorinated biphenyls (PCBs), to varying degrees of severity. PCBs are persistent micropollutants in the environment and harmful to health. A research program "PCB-Axelera" is conducted to address this issue and explore solutions to eliminate or decrease the pollution. In France, all prefectural orders (30/10/2002 and 14/06/2000) and the Decree of 18/04/2002 considered contaminated sediments as waste and allow their landfilling in waste storage facility if their PCB concentrations are between 0.68 ppm and 50 ppm. The main objective of this study is to develop a methodology suitable for installation of non-hazardous waste landfill sites. Geomaterials in this storage will be used as a barrier for confinement of contaminated sediment. The study consists of three parts: 1. In the first part, hydro-chemical characterization of sediments contaminated with PCBs is presented. The sediment classification is performed. The mechanical behavior of the sediment is determined using oedometer tests. As for the hydro-mechanical behavior, it is studied using the filter press and the rigid wall permeameter (PPR). This characterization is essential to provide the best implementation of sediment in the storage center. 2. In the second part, the hydraulic performance (permeability) and mechanical (swelling) of various geomaterials in contact with a fluid extracted from the sediment and other synthetic fluids containing PCBs are being explored. The study of swelling of geomaterials is performed on a laboratory scale while studying its water performance was achieved on two centimetric and metric scales. The pilot scale study was conducted on a 1.2 m3 volume tank. The pilot test was equipped with an automatic rain system and an ultrasonic sensor to measure to measure the follow the settlements of the sediment. The permeability of sediments and geomaterials were measured using the pilot test under actual storage conditions . 3. In the third part, a 1D hydraulic model is developed to follow the waterfront in a sediment sample subjected to a hydraulic load representing a PPR experiment. The VER method is used. A water model of the sediment is proposed to reproduce the experimental results. The water retention curve of the sediment is calculated using Durner’s model (1994). The experimental results show that the degree of PCB contamination of the sediments does not affect the hydro-mechanical behavior and therefore the hydro-mechanical performance of the studied geomaterials studied. Numerical simulation results of the hydraulic behavior of sediment are consistent with the experimental results. The solution of landfilling the PCB contaminated sediment is possible since it assure the confinement of the pollution and eliminates the risk of environmental contamination.
577

Hotel v Čeladné - stavebně technologický projekt / Hotel in Čeladná - Construction technological project

Janek, Stanislav January 2012 (has links)
This thesis is focused on the developing of the implementation phase of the Hotel MIURA in the village of Čeladná. The project is describing particular stages of technological realization of this construction, technology, implementation of the main subject of hydro-insulation system, including design control and test plan for its implementation, design and description of site equipment, the draft contract for realization. The work is further supplemented by an objects schedule and detailing schedule of the main hotel building, a description of major equipment and materials used, budget for the main calculations of the object and other objects.
578

Revitalizační opatření v povodí Rohelnice se začleněním do územního systému ekologické stability / River and floodplain restoration of Rohelnice stream with intergation to territorial systems of ecological stability

Komárková, Adéla Unknown Date (has links)
This work deals with the state of watercourses, the territorial system of ecological stabi-lity and the possibilities of improvement for a state close to nature. The Rohelnice river basin and the solved watercourses are located in the Olomouc Region in the Morava River Basin. HEM - Hydroecological monitoring is a part of the assessment of the state of watercourses, which is a requirement of the European Water Framework Directive. The work contains the elaboration of a literature search on this topic with a focus on water retention in the landscape and the possibility of improving ecological stability in the basin. The content of the diploma thesis is to evaluate the hydromorphological status of watercourses in the Rohelnice river basin with the selection of sections on watercourses and places in the wider river basin for elements of ecological stability on the basis of zoning plans of affected cities and municipalities and improvement of the overall ecological status in the Rohelnice river basin.
579

The climate impact of fishways : A life cycle assessment of Blyberg’s and Spjutmo’s up- and downstream fishways

Lundin, Ellen, Liljenberg, Lovisa January 2023 (has links)
The Swedish national plan for reapproval of hydropower describes that hydropower plants (HPPs) are required to be reassessed to ensure that modern environmental conditions are set for the permits. Since dams and HPPs create barriers for migrating fish and consequently disfavor biological diversity, one consequence of the national plan is that fishways are being constructed. This, in combination with an old, unfinished approval procedure from the 1960’s, resulted in the construction of three up- and downstream fishways in Mora municipality, at the HPPs in Spjutmo, Blyberg and Väsa. To fulfill requirements in regard to the fishway’s incline and safety, but at the same time minimize the need of space, the fishways have new, innovative and not yet tested design features. One of these features is the “parking garage” layout of the upstream fishway. Despite these features, the fishways take up a large amount of space and thus require large amounts of blasting, excavation and materials such as concrete and steel parts. These are climate impact influence intensive procedures and materials, but the construction has so far not been evaluated from a climate impact perspective. This, in combination with a lack of studies on the climate impact of fishways, has resulted in this project.The aim of this project was to examine the climate impact caused by the fishways in Spjutmo and Blyberg, to identify what affects the total climate impact as well as providing measures that could reduce the climate impact for future similar fishways. To provide an extensive overview of the climate impact that the fishways cause during their entire lifetime, the method life cycle analysis (LCA) was used. The construction of the fishways at Väsa HPP starts later than for Spjutmo and Blyberg, and therefore Väsa is excluded from the scope due to the lack of required information.The fishways in Spjutmo and Blyberg have the same design features, but the material consumptions differ due to their differences in head. Spjutmo’s head is 21,4 meter and Blyberg’s is 11 meter. A larger head generally results in a longer fishway which in turn results in a more material consuming construction. This resulted in the total life cycle climate impact being twice as big for Spjutmo as for Blyberg, 2 807 tonne CO2-eq respectively 1 361 tonne CO2-eq. The resource extraction is the LCA- phase that contributes the most. Concrete and its reinforcement have the biggest share of that impact, followed by mechanical parts and other steel products, road construction process in Spjutmo and the excavation process in Blyberg. Based on this result, it can be concluded that the materials and components contribute more to the fishways’ total climate impact, rather than processes. Roughly 80 % of the total climate impact origins from the upstream fishway, while the rest either stems from the downstream fishway or others. Sensitivity analyses include the climate impact caused by the fishways using some water that otherwise could have been used to generate electricity from, and the result indicates that all examined alternative energy sources would result in larger climate impact compared to if the electricity was generated by hydropower.One of the result’s uncertainties is that the fishways were under construction while this project was performed. Therefore some assumptions was made to compensate for lack of data. For example, the future electricity consumption was scaled up based off the then used electricity data. However, even if some amounts of required materials and processes changed as time went by, the changes did not make a significant difference from the bigger perspective. Sensitivity analyses that examined the climate impact of a delay in the construction also showed that the processes that are most likely to continue turned out to have a relatively small climate impact. Thus, this issue might not be as problematic as initially thought.Although the result is presented in total values, the result is also provided per a functional unit (FU) level in accordance with traditional LCA methodology. This was to facilitate a comparison for future LCAs on other fishways. The FU in this project was decided to be “One meter head for a technical, stationary, up- and downstream fishway in connection to a medium or large run-of-river hydropower plant in a cold tempered climate zone”. For future studies, LCAs on different types of fishways using the proposed FU is recommended.
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Hydro-mechanical coupled behavior of brittle rocks: laboratory experiments and numerical simulations

Tan, Xin 16 January 2014 (has links)
‘Coupled process’ implies that one process affects the initiation and progress of the others and vice versa. The deformation and damage behaviors of rock under loading process change the fluid flow field within it, and lead to altering in permeable characteristics; on the other side inner fluid flow leads to altering in pore pressure and effective stress of rock matrix and flow by influencing stress strain behavior of rock. Therefore, responses of rock to natural or man-made perturbations cannot be predicted with confidence by considering each process independently. As far as hydro-mechanical behavior of rock is concerned, the researchers have always been making efforts to develop the model which can represent the permeable characteristics as well as stress-strain behaviors during the entire damage process. A brittle low porous granite was chosen as the study object in this thesis, the aim is to establish a corresponding constitutive law including the relation between permeability evolution and mechanical deformation as well as the rock failure behavior under hydro-mechanical coupled conditions based on own hydro-mechanical coupled lab tests. The main research works of this thesis are as follows: 1. The fluid flow and mechanical theoretical models have been reviewed and the theoretical methods to solve hydro-mechanical coupled problems of porous medium such as flow equations, elasto-plastic constitutive law, and Biot coupled control equations have been summarized. 2. A series of laboratory tests have been conducted on the granite from Erzgebirge–Vogtland region within the Saxothuringian segment of Central Europe, including: permeability measurements, ultrasonic wave speed measurements, Brazilian tests, uniaxial and triaxial compression tests. A hydro-mechanical coupled testing system has been designed and used to conduct drained, undrained triaxial compression tests and permeability evolution measurements during complete loading process. A set of physical and mechanical parameters were obtained. 3. Based on analyzing the complete stress-strain curves obtained from triaxial compression tests and Hoek-Brown failure criterion, a modified elemental elasto-plastic constitutive law was developed which can represent strength degradation and volume dilation considering the influence of confining pressure. 4. The mechanism of HM-coupled behavior according to the Biot theory of elastic porous medium is summarized. A trilinear evolution rule for Biot’s coefficient based on the laboratory observations was deduced to eliminate the error in predicting rock strength caused by constant Biot’s coefficient. 5. The permeability evolution of low porous rock during the failure process was described based on literature data and own measurements, a general rule for the permeability evolution was developed for the laboratory scale, a strong linear relation between permeability and volumetrical strain was observed and a linear function was extracted to predict permeability evolution during loading process based on own measurements. 6. By combining modified constitutive law, the trilinear Biot’s coefficient evolution model and the linear relationship between permeability and volumetrical strain, a fully hydro-mechanical coupled numerical simulation scheme was developed and implemented in FLAC3D. A series of numerical simulations of triaxial compression test considering the hydro-mechanical coupling were performed with FLAC3D. And a good agreement was found between the numerical simulation results and the laboratory measurements under 20 MPa confining pressure and 10 MPa fluid pressure, the feasibility of this fully hydro-mechanical coupled model was proven.

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