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Soil Building Processes in Reconstructed Tree Islands in The Everglades, FloridaRodriguez, Andres F. 13 November 2013 (has links)
Soil building processes were studied in reconstructed tree islands in the Loxahatchee Impoundment Landscape Assessment, Florida. Soil building was evaluated by measuring litter production, litter decomposition, soil accretion, and changes in soil elevation under different hydrologic conditions, and by determining physicochemical characteristics of newly accreted soils. Tree islands showed higher litter production and soil accretion but a larger loss of soil elevation caused by subsidence at higher elevations and shorter inundation periods. Newly accreted soils exhibited higher nutrient concentrations, and organic matter (OM) than older soils. Most of the soil phosphorus was stored in the organic fraction. A positive correlation was found between soil nutrients and OM. Reconstructed tree islands are increasing in soil OM and nutrients, generating a positive feedback that increases tree productivity, and soil building. These findings contribute to the understanding of tree islands’ dynamics and can be used by managers for restoration efforts in the Everglades.
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A study about the influency of regional rainfall of the Paraíba VAlley in the leve water volume of the artificial Lake of Paraibuna, SP. / Um estudo sobre a influência da precipitação regional no Vale do Paraíba no nível de água do reservatório de Paraibuna, SP.Matheus Valério Cezario 24 March 2005 (has links)
The water volume of the artificial lake of Paraíbunas Reservoir has systematically been decreasing for the last 5 years. It is important to study the hydrological cycle to verify the relation between rainfall and the water level of the Reservoir. This work analyzed the rainfall regime of Taubaté and the Global rainfall regime of the Paraíba Valley, where the city is located, in State of São Paulo; it also analyzed the heights of Paraíbunas Reservoir during a 20-year period (1983 2002), as well as the output of Paraíbuna river (1931 2001), associated with a brief study
on Eucalyptus monoculture, population increase in the region, pollution in the river Paraíba do Sul, laws concerning the management of hydrous resources and the development of the tourism around the area of Paraíbunas Reservoir. The data regarding the rainfalls (mm) in Taubaté were collected at the Meteorological Post of the University of Taubaté, the global data regarding Paraíba Valley were obtained at NASA (GCPC), the Reservoir heights (m) were provided by CESP and the output data (m2/s) were obtained at ON.S. There is a good relation between the rainfalls in Taubaté and the Global ones, but there is not a direct relation between them and the Reservoir level. During 2000, 2001 and 2002, rainfall levels were average and heights were low in the Reservoir, with its lowest average in 2002 (701.5m). The correlation coefficient between annual rainfall totals in Taubaté and the Global 13 number was 0.72. The highest correlation between both is obtained in Spring (0.79), and the lowest, in Summer (0.46). We simulated the potential impacts of Eucalyptus reforestation over the hydrous balance of the region. We concluded that, with the current rainfall regime, this activity directly influences the amount of water to be made available by surface outflow to the River Basin of the region. In spite of this unfavorable effect, the Eucalyptus culture has improved the socioeconomic development of the areas where they are implanted. According to the facts studied, we concluded that the lowering of the Paraíbunas Reservoir water level is not linked only with the rainfall regime, for many other factors interfere in this destock, namely: population growth, increase of Eucalyptus monoculture, pollution, deforestation, silting of rivers, output maneuver, among others. / O lago artificial da Barragem de Paraibuna vem diminuindo sistematicamente seu volume de água nos últimos 5 anos, sendo que o estudo do ciclo hidrológico é importante para se verificar a relação entre precipitação e o nível de água do Reservatório. Este trabalho analisou o regime de precipitação de Taubaté e Global (Região do Vale do Paraíba) e as cotas do Reservatório de Paraibuna no período de 20 anos (1983-2002); bem como as vazões do rio Paraibuna (1931 2001), associados ao um breve estudo sobre a monocultura do Eucalipto, o aumento da população na região, a poluição do rio Paraíba do Sul, a legislação sobre gerenciamento dos recursos hídricos e o desenvolvimento do turismo na área do reservatório de Paraibuna. Os dados da precipitação (mm) de Taubaté foram coletados no posto meteorológico da UNITAU, os dados da precipitação Global foram obtidos da NASA (GCPC), as cotas (m) do Reservatório foram cedidos pela CESP e os dados das vazões (m/s) foram obtidos da ONS. Há uma boa relação entre a precipitação Global e a de Taubaté, mas não uma relação direta entre estas precipitações e nível do Reservatório. Os anos de 2000, 2001 e 2002 tiveram índices de precipitação dentro da média e cotas baixas no Reservatório, que apresentou a menor média das cotas no ano de 2002 (701,5m). O coeficiente de correlação entre totais anuais de precipitação de Taubaté e Global foi de 0,72. A estação da Primavera apresenta a maior correlação entre os dados de precipitação Global e de Taubaté 11 (0,79), sendo que o Verão apresenta a menor correlação (0,46). Foram realizadas simulações de possíveis impactos do reflorestamento do eucalipto no balanço hídrico da região, chegando-se à conclusão de que, com o atual regime pluviométrico, a atividade de plantio de Eucalipto influencia diretamente na quantidade de água a ser disponibilizada através do escoamento superficial para a Bacia Hidrográfica da região. Apesar deste efeito desfavorável as plantações de Eucalipto têm trazido uma melhoria no desenvolvimento sócio-econômico para as regiões onde estão inseridas. Diante dos fatos estudados concluiu-se que o rebaixamento do nível de água do
reservatório de Paraibuna não está atrelado somente à ocorrência da precipitação, pois muitos outros fatores, interferem neste desestoque, a saber: crescimento populacional, aumento da monocultura de Eucalipto, poluição, desmatamento, assoreamento dos rios, manejo das vazões, entre outros.
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Monitoring Hydrology in Created Wetland Systems with Clayey SoilsTroyer, Nicole Loraine 18 September 2013 (has links)
This research project evaluated the overall hydroperiod and effects of monitoring well design parameters on observed levels of saturation in created wetlands with high-clay subsoils at the Cedar Run 3 mitigation bank site in Prince William County, Virginia. Three complete replications of an electronic central array and an associated surrounding array of manually monitored wells and piezometers were installed. The electronic arrays contained a U.S. Army Corps of Engineers (USACOE) standard monitoring well, as well as piezometers and tensiometers at three depths. The manually monitored well + piezometer arrays (3 per location; 9 total) consisted of 12 variants of screen types and filter pack materials, well diameter, and unlined bore holes. The site exhibited a complex seasonal hydroperiod ranging from ponded winter conditions to deep (< -50 cm) summer dry down. The site also exhibited epiaquic (perched) conditions following summer and fall precipitation events. Apparent water levels in deep (> 1 m) piezometers exhibited an unusual hydroperiod with highest levels in summer. Differences in well/piezometer diameter, design, and packing texture/fit produced surprisingly different apparent water levels that varied from ~ 4 to over 28 cm during both the winter ponded periods and summer subsoil water table flux periods. Thus, one important finding is that relatively simple differences in well designs can have dramatic effects on observed water levels. Overall, the standard USACOE appeared to be relatively accurate for predicting saturation levels during ponded periods, but nested piezometers are preferred and more accurate for the drier summer and fall. / Master of Science
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Řídicí jednotka automatického manipulačního systému pro laboratoře / Control unit for automatic laboratory manipulation systemVávra, Tomáš January 2014 (has links)
This document deals with devices which are used for the automatic Gram staining. The document starts by a research with the aim to discover existing devices and to compare them to the concept of the device developed by company Biovendor. There is theoretically and then practically dealed with the methods of the rotor imbalance detection and measurement of water-level. The Practical part of this document describes the development of the control unit with the microcontroller ARM Cortex-M3 which will be used for the prototype development of Biovendor’s device. The Last part describes measurement of imbalance of three different rotors with the aid of the control unit.
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Development and design of a prototype for monitoring the water level in water wells using LoRaWANDalkic, Yurdaer, Alshekhly, Zoubida January 2018 (has links)
En översvämning kan inträffa när som helst och var som helst i världen. En översvämning börjar när vattennivån ökar, särskilt i dagvattenbrunnar i stadsområden. Genom att utnyttja de olika moderna teknologier som Internet of Things (IoT), förluster som orsakas av en översvämning kan minskas. Därför behövs en IoT-lösning för att övervaka vattennivån i brunnarna.Syftet med denna avhandling är att undersöka hur man konstruerar och implementerar ett IoT-baserat system som övervakar vattennivån för att bygga en prototyp med LoRaWAN teknologi. Konstruktionen av prototypen utförs genom att följa stegen i en iterativ systemutvecklingsmetod. Prototypen använder ett offentligt Lora-nätverk, särskilt The Things Network (TTN). Prototypens funktioner är att mäta vattennivån med en ultraljudssensor, sända mätdata via LoRa till TTN och visualisera data på en visualiserings plattform "Cayenne" i realtid. Systemet är testad i en laboratoriemiljö. Resultaten av den konstruerade prototypen visar att den mäter vattennivån och skickar mätdata när vattennivåns tillstånd ändras. Dessutom visualiseras datan på visualiserings plattformen Cayenne. / A flood may occur anytime and anywhere in the world. A flood starts when the water level increases, especially, in the wells in the urban areas. By taking advantage of the modern technology, such as Internet of Things (IoT), the losses caused by the flood can be reduced. Therefore, an IoT-solution is needed for monitoring the water level in the wells.The aim of this thesis is to investigate how to design and implement an IoT-based system that monitors the water level to build a prototype using LoRaWAN technology. Building the prototype is done by following the steps of an iterative system development method. The prototype uses a Lora public network, specifically The Things Network (TTN). The functions of the prototype are measuring the water level by an ultrasound sensor, sending the measurement data through LoRa to TTN, and visualizing the data on the "Cayenne" dashboard in real-time. The system is tested in a lab environment. The results of the constructed prototype show that the prototype measures the water level and sends the measurement data whenever the state of the water level is changed. Additionally, the data is visualized on the Cayenne dashboard.
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Investigation of pattern recognition algorithms to determine depth and volume of water inside the sump of a pumping stationStjern, Magnus, Jansson Aldenfalk, Staffan January 2014 (has links)
Pattern recognition is now considered a fundamental building block in many fields. The ability to interact with a computer or vice versa is no longer limited by how fast the computer is, but rather what an application developer can think of. Today many modern, real-time applications, such as high performance and high quality graphics can be combined with a Xbox Kinect to do object tracking and Google Glass to provide a heads up display. These applications can also be combined with other sensors and actuators to produce monitoring systems that can give facilities' operators "telepresence" throughout a facility. To be able to computationally interpret movement or patterns in an image it is imperative to investigate the application of this technology. The research conducted at Xylem has focused on a very specific problem: How can pattern recognition be utilized to dynamically determine the volume and depth of water in a sump at a pumping station. The equipment currently used to determine the water level depends upon being either below or alongside the water's surface, this puts the equipment under great stress due to the nature of a pumping station. Xylem is one of the leading global water technology companies, hence sewage-pumps are one of its main products. The main equipment utilized in this thesis project consists of a camera attached to the interior at the top of the sump in a pumping station connected to a computer. The software developed includes a simple graphical user interface (GUI). This GUI was implemented in C# and is designed to continuously collect data from a camera for subsequent analysis. Our algorithm utilizes anti-correlation between many images taken during a short interval to determine the actual water level. The known dimensions of the sump are then used to calculate the volume of water. Most of the depth values produced by our software were correct and we were able to correctly estimate the water level with an error of less than 4 cm, this corresponds to a volume error of 62 liters for a 140 cm wide sump. Our algorithm was able to monitor the depth over time inside a pumping station in a simulated live environment. This accuracy is obtained with a time window of 1 second. The results of this system are important because it shows that it is possible to use a camera to measure water depth. This provides pump owners and operators with valuable information regarding the current state of the pump, both in terms of current water depth and an image of possible anomalies such as the presence of foreign objects in the sump. / Mönsterigenkänning betraktas numera som en grundläggande byggsten inom många områden. Möjligheten att kunna interagera med en dator eller vice versa är inte längre begränsat av datorkraft, utan snarare av vilken slags applikation en utvecklare kan komma på. Idag kan många moderna realtidsapplikationer, såsom högpresterande datorer och högkvalitativ grafik kombineras med en Xbox Kinect för att utföra objektspårning och Google Glass för att åstadkomma en huvudburen display. Dessa applikationer kan även kombineras med andra sensorer samt manöverdon för att skapa övervakningssystem som kan ge anläggningsoperatörer möjlighet till fjärrövervakning i en anläggning. För att beräkningsmässigt kunna tolka rörelser eller mönster i en bild är det nödvändigt att utforska tillämpningen av denna teknologi. Forskningen utförd på Xylem har fokuserat på ett väldigt specifikt problem: Hur kan mönsterigenkänning användas för att dynamiskt detektera volymen och vattendjupet i en sumpstation? Utrustningen som vanligen används för detektering av vattennivån är beroende av att vara antingen under eller i linje med vattennivån. Detta utsätter utrustningen för stora påfrestningar på grund av miljön inuti i en pumpstation. Xylem är ett av de globalt ledande företagen inom pumpar, följaktligen är avloppspumpar en av deras huvudsakliga produkter. Den huvudsakliga utrustningen som används i detta projekt är en kamera kopplad till en dator som monteras på den inre och översta delen av en sump i en pumpstation. Programvaran som utvecklats inkluderar ett enkelt grafiskt interface. Detta interface implementerades i C# och är designat för att kontinuerligt samla in data från en kamera för efterföljande analys. Vår algoritm använder sig utav anti-korrelationen mellan många bilder tagna under ett kort intervall för att bestämma det verkliga vattendjupet. De kända dimensionerna av pumpstationen används sedan för att beräkna volymen av vattnet. De flesta djupmätningar genererade av vårt program var korrekta och vi har lyckats korrekt uppskatta vattennivån med ett fel på mindre än 4 cm. Detta motsvarar ett volymfel på 62 liter för en sump med en diameter på 140 cm. Vår algoritm har lyckats övervaka hur djupet ändras med tiden i en live-simulerad miljö. Denna noggrannhet erhålles med ett tidsfönster på 1 sekund. Resultatet av detta system är viktigt eftersom det visar att det är möjligt att använda en kamera för att mäta vattendjup. Detta ger pumpägare och operatörer värdefull information om befintligt skick av en pumpsump, både i form av aktuellt vattendjup samt en bild av möjliga avvikelser såsom förekomsten av främmande objekt inuti sumpen.
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Determination of Lake Water Level using Space Laser AltimetryRenfei Li (16674087) 02 August 2023 (has links)
<p>The spaceborne lidar Ice, Cloud, and land Elevation Satellite (ICESat)-2 provides the ATL13 data product for inland water bodies. However, its quality characteristics are not yet fully understood. This study presents a robust method for extracting lake water level data and makes a comprehensive evaluation on the determined water levels. The selected study areas are Lake Huron and Lake Superior, which are part of the Great Lakes. The extracted water levels from ATL13 over a period of four years are validated by using the field measurements at the closest NOAA hydrological stations. The evaluation is carried out in terms of data specifications, wind speed, frozen precipitation, distance of photon segments to hydrological stations, data acquisition time, and beam intensity. The determined water levels are then further used for seasonal monitoring and modeling of water surface. This work demonstrates the critical need for outlier removal and the capability of the ATL13 data. A total bias of 9 - 10 cm is found in the ATL13 product. It is found that frozen precipitation can lead to an overestimation (~ 5 cm) of the water level. However, the uncertainty of water level determination is not found to be significantly related to the laser beam intensity and data acquisition time. We expect that these findings will be valuable for users employing the ATL13 inland water body product and for developers producing future versions of the ATL13 product.</p>
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Experimental investigation on the effects of bed slope and tailwater on dam-break flowsliu, Wenjun, Wang, Bo, Guo, Yakun, Zhang, Jianmin, Chen, Yunliang 03 July 2020 (has links)
Yes / Understanding of the characteristics of dam-break flows moving along a sloping wet bed can help to timely issue flood warning and risk mitigation. In this study, laboratory experiments are carried out in a large flume for a wide range of upstream water depth, bed slopes and tailwater depth. The water level is recorded and processed to calculate the mean velocity and wave celerity. Results show that the increase of the bed slope will significantly accelerate the wave-front celerity for the downstream dry bed, while the negative wave celerity will decrease. When water depth ratio α ≥ 0.3 (defined as the ratio of initial downstream water depth over the upstream water depth of dam), there are extra negative waves propagating towards the reservoir area after the flow has developed for a period of time. When α ≥ 0.6, there are the Favre waves propagating downstream. The water level and the mean velocity fluctuate due to the influence of the extra negative waves and the Favre waves. Such fluctuant frequency increases with the increase of the water depth ratio. The empirical formulas are obtained for the celerity of the first extra negative wave and the first downstream wave. The variation of wave-front height is very similar under three bed slopes investigated in this study, while the maximum wave-front height occurs when α = 0.2. The present study broadens the understanding of the effects of the bed slope and the tailwater level on the movement of the dam-break flows. Furthermore, experimental results are also compared with some analytical solutions. The validity of the assumptions made during the development of these analytical solutions and their limitations are discussed by comparing with the experimental measurements. / The National Natural Science Foundation of China (Grant No: 51879179), the Open Fund from the State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University (SKHL1809) and Sichuan Science and Technology Program (No. 2019JDTD0007).
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Applications of Synthetic Aperture Radar Data to study Permafrost Active Layer and Wetland Water Level ChangesJia, Yuanyuan 23 October 2017 (has links)
No description available.
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Applications of Synthetic Aperture Radar (SAR)/ SAR Interferometry (InSAR) for Monitoring of Wetland Water Level and Land SubsidenceKim, Jin Woo 27 September 2013 (has links)
No description available.
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