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Tree-Ring Dating of Colorado River Driftwood in the Grand CanyonFerguson, C. W. 23 April 1971 (has links)
From the Proceedings of the 1971 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 22-23, 1971, Tempe, Arizona / The development of tree-ring chronology for bristlecone pine (Pinus aristata), stretching over 8,200 years, has been used to calibrate the radiocarbon time scale. An extensive deposit of driftwood in Stanton's cave in the grand canyon was estimated to have been deposited on the cave floor about 12,000 years ago on the basis of the 4,095-year radiocarbon age of a split-twig figurine on the surface of the cave floor. However, the initial driftwood specimen gave the surprising C-14 age of 35,000 years. A tree-ring dating study was therefore undertaken on driftwood in the grand canyon in order to: (1) evaluate the driftwood deposit in Stanton's cave; (2) provide a basis for interpreting c-14 dates from canyon archaeological sites; and (3) document a technique for deriving some concept of pre-dam hydrology, especially maximum high water levels. The percentage of dated specimens found indicated that the approach was feasible. A likely interpretation of the seemingly early c-14 dates at archaeological sites is that prehistoric man used old driftwood, as does modern man in the canyon. Tree-ring dates from wood above the pre-dam high water mark indicate that maximum 100-year flood evidence can be obtained.
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The Application of Step-Drawdown Pumping Tests for Determining Well Losses in Consolidated Rock AquifersUhl, V. W., Jr., Joshi, V. G., Alpheus, A., Sharma, G. 12 April 1975 (has links)
From the Proceedings of the 1975 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 11-12, 1975, Tempe, Arizona / The concept of a step -drawdown test was first introduced by Jacob, and further modifications in the technique were made by Rorabaugh. Analysis of step -drawdown test data enables the quantification of the components of drawdown due to formation or aquifer loss, and due to well losses in a pumped well. This technique has been used to test approximately 100 wells that were drilled in crystalline and basalt formations in central India. Test data have been analyzed by Rorabaugh's method and by a graphical method, and the results of a number of tests are presented and discussed. Anomalies in the test analysis often proved helpful for interpreting aquifer irregularities. In general, the well loss constant decreases with an increase in specific capacity and the aquifer loss constant decreases with increasing transmissivity. Significant reductions in specific capacity during a step test occur in wells with high well losses. An attempt is made to quantify the well losses in a consolidated rock well, and a number of practical applications of step -drawdown tests are discussed.
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Modelización hidrológica de un área experimental en la cuenca del Río Guayas en la producción de caudales y sedimentos / Modelización Hidrológica de un área experimental en la cuenca del Río Guayas / Hydrologic Modelling of an experimental area in the Guayas River basin to quantify liquid and solid flow production.Tapia Aldas, Juan Carlos 30 October 2012 (has links)
La cuenca del Río Guayas es considerada como la zona de mayor producción agrícolaganadera del Ecuador, por tanto su estudio es importante para tener una producción sustentable y sostenible en el tiempo. Su área abarca una superficie de 3 millones de ha, está conformada por zonas altas ubicadas sobre la Cordillera Occidental, zonas medias situadas en las laderas de la cordillera y zonas bajas que corresponde a las grandes llanuras aluviales de la costa donde se asienta la mayor concentración de población. Debido a la estructura morfológica de la cuenca y a los procesos antropogénicos que se desarrollaron sin tomar en cuenta planes conservacionistas adecuados en manejo de cuencas hidrográficas, las zonas bajas son las que mayormente se han visto afectadas durante años, por eventos de inundación frecuentes y prolongados, que generan grandes pérdidas materiales e incluso vidas humanas, afectando severamente su potencial económico y limitando el transporte fluvial. Siendo por este motivo, de fundamental importancia la determinación de la producción de caudales y sedimentos que se aportan al Río Guayas. El objetivo de esta tesis es la modelación hidrológica de la microcuenca del Río Toachi, tributario del Río Guayas, para cuantificar la producción de caudales líquidos y sólidos que se generan a partir de la caracterización morfológica e hidrometeorológica. Se aplicaron modelos hidrológicos y empíricos integrando los Sistemas de Información Geográfica (SIG) en el tratamiento de información espacial, generando una gran base de datos georreferenciada de la cuenca de estudio. Como resultado, se obtuvieron los parámetros morfológicos del relieve, de la forma y relativos a la red hidrográfica a nivel cuenca de estudio y sus unidades hidrológicas (subcuencas), destacando la forma alargada de la cuenca con pendientes fuertes en la cabecera, accidentadas en la zona media y suave en la desembocadura, con una superficie de 50.371,74 ha. Presenta valores de densidad de drenaje bajos con crecientes de menor magnitud y menor probabilidad de ocurrencia de eventos torrenciales, con un bajo poder erosivo. Se generaron los mapas temáticos como: topográfico, hidrográfico, orientación, iluminación y pendientes de las laderas, suelo, uso del suelo y cobertura vegetal, isotermas, isoyetas, zonas climáticas. Se realizó un estudio de los parámetros hidrometeorológicos y su dinámica en la cuenca de estudio a nivel zonas para cuantificar los caudales líquidos por medio del HECGeo-HMS. Se calibró y validó el modelo hidrológico HEC-HMS ® cuantificando el caudal simulado a la salida de la cuenca de estudio para que pueda ser usado en otras cuencas de iguales características morfométricas. Se calcularon los factores de la Ecuación Universal de Pérdida de Suelo (USLE) y la Tasa de Erosión Hídrica Superficial de la cuenca del Río Toachi y de las respectivas unidades hidrológicas. Además se realizó la cartografía particular de los parámetros de la USLE de la cuenca del Río Toachi con SIG para un análisis geoespacial. / Guayas River Basin is considered one of the greatest farming land and crop yield production areas of Ecuador. So this study is important to have a sustainable production through the time. It comprises 3 million hectares; which is compound by highlands located on the West mountain range, mountain passes located on the slopes and valleys that correspond to vast alluvial plains where most of the population is concentrated. Because of the basin morphological structure and the anthropogenic processes that have been developed regardless of preservation planning programs appropriate for hydrographic basin management, valleys have been mainly affected by frequent and long floods over years. These latter events have cost both damages and even losses of lives drastically altering the economic potential and limiting fluvial transportation. The fact of determining the water level and sediment production that are provided to Guayas River is, thus, of utmost importance. The aim of this thesis is the hydrologic modeling of Toachi River micro basin located within Guayas River basin to quantify liquid and solid flow production that stems from the morphological and hydrometeorological characterization. To this purpose, hydrological and empirical models were applied integrating the Geographic Information Systems (GIS) in the analysis of spatial data, thus, generating a great georreferencial database of the studied basin. As a result, morphological parameters of the relief, the shape and relating to the hydrographic network at a basin studied level and its hydrological units (sub-basin) were obtained. The elongated shape of the basin with steep slopes at the headwaters source, rugged in the passes and smooth in the mouth of the River with an extension of 50.371,74 ha. are highlighted. It presents low density drainage values with a growing water level of less scale and less probability of torrential events resulting in a low erosive power of the basin. Topic maps were generated like: topography, hydrography, orientation, illumination and hillside slopes, soil, soil use and vegetation cover, isotherms, isohyets, climate zones. Hydrometeorological parameters study was made and its dynamic in basin studied level to quantify the liquid flows by HECGeo-HMS. The hydrologic model HEC-HMS ® was calibrated and validated quantifying the water level simulated at the end of the studied basin in order to be used by other basins with similar morphometric characteristics. Universal Soil Loss Equation (USLE) and Superficial erosion rate factors of the Toachi River basin and its hydrologic units were calculated. And the particular cartography of the USLE parameters of the Toachi River basin with GIS for a geospatial analysis was made.
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Vestavěný systém pro automatizaci chovné stanice akvarijních ryb / Embedded System for Automation of Aquarium Fish Breeding StationMoc, Filip January 2018 (has links)
This master's thesis is concerned about embedded system for automatic water renewal in aquariums. Besides water renewal system also controls lights and ventilation in aquarium fish breeding station. In this report you will find informtions about technology relevant to automation of aquarium fish breeding station. Also you will find here informations about design and implementation of my specific final working solution.
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Bezdrátová čidla pro měření hladiny vody / Wireless water level sensorsPospíšil, Jakub January 2010 (has links)
The thesis deals with both scheme and its implementation of water-level metering apparatus. This data are send wireless into 500 m distant station. Potential ways of solution are gradually studied and final design suggested. Detailed implementation methods are described in the following section. Ultrasonic sensors are employed for level measurement and controlling element is processor ATmega162, data are transmitted by transceiver RC1280HP. Apparatus is suggested with a view to the lowest power consumption considering it will be supplied only with a accumulator. Solving of accepting station is not a part of the thesis. Functional tested sample is understated in the execution section.
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Posouzení vodního díla Těšetice za povodní / Safety Assesment of the Těšetice Dam during FloodsVaněk, Petr January 2016 (has links)
The Diploma Thesis focuses on the assessment of the current state of VD Tesetice to convert KPV parameters Q1000. Based on this evaluation, the thesis proposes corrective actions on waterwork constructions for the purpose of protection of their functioning during floods. Proposed corrective actions consist of designing new or additional safety features, mainly security spillway in abutment terrain.
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Improving Photovoltaic Panel Efficiency by Cooling Water CirculationJoseph, Jyothis 12 1900 (has links)
This thesis aims to increase photovoltaic (PV) panel power efficiency by employing a cooling system based on water circulation, which represents an improved version of water flow based active cooling systems. Theoretical calculations involved finding the heat produced by the PV panel and the circulation water flow required to remove this heat. A data logger and a cooling system for a test panel of 20W was designed and employed to study the relationship between the PV panel surface temperature and its output power. This logging and cooling system includes an Arduino microcontroller extended with a data logging shield, temperature sensing probes, current sensors, and a DC water pump. Real-time measurements were logged every minute for one or two day periods under various irradiance and air temperature conditions. For these experiments, a load resistance was chosen to operate the test panel at its maximum power point. Results indicate that the cooling system can yield an improvement of 10% in power production. Based on the observations from the test panel experiments, a cooling system was devised for a PV panel array of 640 W equipped with a commercial charge controller. The test data logger was repurposed for this larger system. An identical PV array was left uncooled and monitored simultaneously to compare the effect of cooling, demonstrating that the cooled array provided up to an extra 132W or 20% of maximum power for sunny weather conditions. Future expansion possibilities of the project include automated water level monitoring system and water filtration systems.
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Návrh regulace tlaku a průtoku v soustavě čerpadlo-nádrž / Pressure and Flow Rate Regulation Design for Pump-Tank SystemKovář, Jiří January 2014 (has links)
The proposed work is dealing with control design of pump-tank system as part of broader water-supply network with using of mechatronic approach. The main goal of this work is design of control for regulation of flow, pressure and water level in tank in water-supply network of Vsetin city. This water-supply network consists of various components, such as pumps, pipes, valves, tanks etc. For the purpose of the control design is necessary to create a model of pipe network. The solution of hydraulic analysis is obtained by using the gradient method, which was implemented into the software solution named ADAM. The results of hydraulic analysis are compared with measured values of flow and pressure and difference of these values has to be minimalized by proposed calibration and verification process. The calibration and verification process was implemented in software ADAM. The essence of design control is formulating control problem as optimization problem. Therefore the output of higher control layer is set of procedural rules, which determines for example speed of pumps in time etc. Results were verified by using for this purpose developed computational server (ADAM Server).
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Energetické úspory velkých objektů / Energy saving of large objectsŘehák, Pavel January 2018 (has links)
The aim of this diploma thesis is to evaluate the economical measures using own heat and power production using cogeneration units, use of renewable resources to partially cover the consumption of objects, reduction of thermal losses by evaporation in the outdoor swimming pool and overall increase of waste heat utilization by exchanger heat exchangers from flue gas and heat from waste water.
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Optimizing the design of two-stage ditches to improve nutrient and sediment retentionEnglund, Sofia January 2020 (has links)
Negative effects on water quality are created by eutrophication of the world’s water resources. Mitigation measures have been implemented, but poor improvements in water quality have been observed. Two-stage ditches have the possibility to increase nutrient and sediment retention to reduce eutrophication in receiving water bodies. A two-stage ditch has floodplain terraces on each side of the ordinary main channel. The terraces are available for flooding during high water flows and enables decreases in flow velocities. However, more knowledge is needed about the two-stage ditch and its effect in Swedish landscapes. The aim of the project was to study the two-stage ditch design with focus on water retention. Optimization of the two-stage ditch design was made by modeling and simulating design parameters and vegetation in the software Hydrologic Engineering Center’s River Analysis System (HEC-RAS). An existing two-stage ditch in Sweden was used as base and comparison to the theoretical model. In addition, a climate change scenario was studied to evaluate the impact of increased storm events in a two-stage ditch. Results showed that increased retention time of water, nutrients, and sediments theoretically can be given by designing two-stage ditches with maximum terrace width and minimum terrace height, and with terraces angled away from the main channel. Vegetation should also be kept on both terraces and in the main channel of the two-stage ditch to increase retention time. The study also showed that the two-stage ditch design has the possibility to decrease peak water levels during storm events, which can be expected to increase in the future. The impact on transport of nutrients and sediments from more future extreme hydrological events needs further studies. / Negativa effekter i vattenkvalitet skapas av övergödning i världens vattenresurser. Åtgärder för att begränsa övergödningen har genomförts, men svaga förbättringar i vattenkvalitet har noterats. Tvåstegsdiken har möjligheten att öka retentionen av näringsämnen och sediment för att minska övergödning. Ett tvåstegsdike har terrasser på vardera sida om den vanliga mittfåran. Terrasserna är tillgängliga för översvämning vid höga vattenflöden, vilket möjliggör minskning av flödeshastigheter. Dock krävs mer kunskap för tvåstegsdiken och dess effekt i svenska landskap. Syftet med projektet var att studera designen av tvåstegsdiken med fokus på retention av vattenflöde. Optimering av tvåstegsdikens design genomfördes via modellering och simulering av designparametrar och vegetation i programvaran Hydrologic Engineering Center’s River Analysis System (HEC-RAS). Ett befintligt tvåstegsdike i Sverige användes som bas och jämförelse mot den teoretiska modellen. Ett scenario för klimatförändring studerades även för att utvärdera effekten i ett tvåstegsdike då fler stormevent sker. Resultaten visade att ökad retentionstid for vatten, näringsämnen, och sediment teoretiskt kan ges genom att designa tvåstegsdiken med maximal terrassbredd och minimal terrasshöjd, samt med terrasser vinklade bort från mittfåran. Vegetation bör även behållas på terrasser och i mittfåran av tvåstegsdiket för att öka retentionstiden. Studien visade även att tvåstegs- dikets design har möjligheten att minska toppflöden vid stormevent, vilka kan förväntas öka i framtiden. Påverkan på transport av näringsämnen och sediment från fler framtida extrema hydrologiska event kräver ytterligare studier.
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