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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

Evaluation of methodologies for continuous discharge monitoring in unsteady open-channel flows

Lee, Kyutae 01 December 2013 (has links)
Ratings curves are conventional means to continuously provide estimates of discharges in rivers. Among the most-often adopted assumptions in building these curves are the steady and uniform flow conditions for the open-channel flow that in turn provide a one-to-one relationships between the variables involved in discharge estimation. The steady flow assumption is not applicable during propagation of storm-generated waves hence the question on the validity of the steady rating curves during unsteady flow is of both scientific and practical interest. Scarce experimental evidence and analytical inferences substantiate that during unsteady flows the relationship between some of the variables is not unique leading to looped rating curves (also labeled hysteresis). Neglecting the unsteadiness of the flow when this is large can significantly affect the accuracy of the flow estimation. Currently, the literature does not offer criteria for a comprehensive evaluation of the methods for estimation of the departure of the looped rating curves from the steady ones nor for identifying the most appropriate means to dynamically capturing hysteresis for different possible river flow conditions. Therefore, the overarching goal of this study was to explore the uncertainty of the conventional approaches for constructing stage-discharge rating curves (hQRCs) and to evaluate methodologies for accurate and continuous discharge monitoring in unsteady open channel flows using analytical inference, index velocity rating curves (VQRCs), and continuous slope area method (CSA) with considerations on discharge measurement uncertainty. The study will demonstrate conceptual and experimental evidences to illustrate some of the unsteady flow impacts on rating curves and suggest the development of a uniform end-to-end methodology to enhance the accuracy of the current protocols for continuous stream flow estimation for both steady and unsteady river conditions. Moreover, hysteresis diagnostic method will be presented to provide the way to conveniently evaluate when and where the hysteresis becomes significant as a function of the site and storm event characteristics. The measurement techniques and analysis methodologies proposed herein will allow to dynamically tracking both the flood wave propagation and the associated uncertainty in the conventional RCs.
2

Stanovení konzupmčních křivek na vybraných hydrologicých profilech KFGG / Assessment of rating curves on selected hydrological profiles of the KFGG

Kabelka, Tomáš January 2016 (has links)
This thesis deals with the creation of rating curves and evaluating these curves on profiles KFGG. There are described various methods of extrapolating discharge beyond instrumentally measured data. On selected profiles is performed extrapolation using 1D hydrological model MIKE 11. Data used in this work are obtained by field survey made by workers KFGG. Key words: rating curve, extrapolation, hydrological modeling, ADCP, MIKE 11
3

Kalibrering och funktionskontroll av hydrologisk mätutrustning vid Islandsfallet, Uppsala / Calibration and Functional Assessment of Hydrological Monitoring Equipment at Islandsfallet, Uppsala

Jonsson, Maria January 2019 (has links)
En funktionskontroll har utförts av en nyinstallerad hydrologisk mätutrustning i Fyrisån som rinner genom Uppsala, där analyser av inhämtade vattenprover har jämförts med mätvärden från mätutrustningens sensorer. Genom en interkalibrering med en äldre mätstation har en avbördningskurva tagits fram till mätstationen vilket visade sig vara en enkel metod som gav tillförlitliga värden. De parametrar som sensorn loggar dygnet runt studerades i syfte att hitta samband mellan dessa och transporten av näringsämnen i Fyrisån, mellan fosfor och turbiditet kunde ett sådant samband anas. Fyrisåns vattenkemi speglar markanvändningen i avrinningsområdet där den kalkrika marken ger en förhöjd konduktivitet och jordbruksmarkerna tillför kväve. Då Fyrisån passerar Uppsala sker en ökning av lösta och suspenderade partiklar samt närsalter. Även årstidsvariationer gällande vattenkvalitén observerades där vattenstånd och turbiditet ökar vid nederbörd samt snösmältning. Konduktivitet visar på ett motsatt förhållande där konduktiviteten minskar vid ökat vattenstånd. / A functional assessment has been carried out for newly installed hydrological monitoring equipment in the river Fyris, in Uppsala, Sweden. Collected water samples were analyzed and compared with measured values from the measuring equipment's sensors. A rating curve was produced for the station by implementing an intercalibration with an older measuring station; this proved to be an easy method which yielded reliable values. The different parameters that the sensor registered every 30th minute were studied in order to find correlations between these and the transport of nutrients in the river Fyris. A correlation between phosphorus and turbidity was observed. The water chemistry in the river Fyris reflects the land use in the catchment area, and the elevated conductivity is caused by calcareous soils and nitrogen is derived from agricultural practices. When the river Fyris passes the city Uppsala an increase in dissolved and suspended particles and nutrients can be seen. Seasonal variations regarding the water quality can be observed as the water level and the turbidity increases during precipitation and snowmelt. The conductivity indicates an inverse relationship with decreasing values as the water level rises.
4

Non-unique stage-discharge relations : Bayesian analysis of complex rating curves and their uncertainties / Relations hauteur-débit non univoques : analyse bayésienne des courbes de tarage complexes et de leurs incertitudes

Mansanarez, Valentin 02 November 2016 (has links)
Les courbes de tarage complexes, qui prennent en entrée la hauteur d'eau et des variables supplémentaires, sont nécessaires pour établir les chroniques de débit des cours d'eau là où la relation hauteur-débit n'est pas univoque. Dans le même cadre bayésien, des méthodes à base hydraulique sont proposées et testées pour construire les courbes de tarage complexes et estimer leurs incertitudes : des modèles hauteur-gradient-débit (SGD) pour résoudre l'hystérésis due aux écoulements transitoires, des modèles hauteur-dénivelée-pente (SFD) pour résoudre le remous variable aux stations à double échelle, le modèle hauteur-période-débit (SPD) pour résoudre les détarages nets dus aux évolutions du lit. Chaque modèle a été appliqué à des stations hydrométriques variées et évalué grâce à des analyses de sensibilité. Pour chacune des trois sources de non-univocité de la relation hauteur-débit, les méthodes bayésiennes proposées fournissent non seulement une analyse d'incertitude quantitative mais aussi des solutions efficaces à des problèmes récurrents que posent les procédures traditionnelles pour les courbes de tarage complexes. / Complex rating curves, with stage and additional variables as inputs are necessary to establish streamflow records at sites where the stage-discharge relation is non-unique. Within the same Bayesian framework, hydraulically-based methods are introduced and tested to develop complex rating curves and estimate their uncertainties: stage-gradient-discharge (SGD) models to address hysteresis due to transient flow, stage-fall-discharge (SFD) models to address variable backwater at twin gauge stations, stage-period-discharge (SPD) model to address net rating changes due to bed evolution. Each model was applied to contrasting hydrometric stations and evaluated through sensitivity analyses. For each of the three sources of non-uniqueness in the stage-discharge relation, the proposed Bayesian methods provide not only quantitative uncertainty analysis but also efficient solutions to recurrent problems with the traditional procedures for complex ratings.
5

Curva chave para o monitoramento automático de sedimentos na Bacia do Rio São Francisco Falso - PR / Rating curve for automatic monitorament of sediments in basin of the False San Francisco River - PR.

Poletto, Kayla Walquiria Garmus 04 April 2008 (has links)
Made available in DSpace on 2017-07-10T19:24:03Z (GMT). No. of bitstreams: 1 Kayla Walquiria Garmus Poletto.pdf: 11373984 bytes, checksum: 4001fb7e0acd1d130237b83ee319f68d (MD5) Previous issue date: 2008-04-04 / Knowledge of the hydro-sedimentologic behavior of a river basin is basic for the appropriate management and use of their water resources. This work objectified to implement a study about the behavior of suspended-sediment discharge along the basin of false San Francisco River. Based on the available hydrosedimentometric data, had been generated rating-curve of the sediments concentration and outflow; reading of turbid?metro and outflow; reading of turbid?metro and concentration of sediment, and, afterwards, the measurements values of the daily outflow were converted into suspended-sediments discharge. The station of the basin presented daily average outflow of 4,81 m?/s an average suspended-sediment flow about 7,23 ton.day ?־, what it corresponds to a value of a specific suspended sediment load de 5 t.ano?־.km?. Also the physiographic characterization of the Basin of the False San Francisco River. / O conhecimento do comportamento hidrossedimentol?gico de uma bacia hidrogr?fica ? fundamental para a adequada gest?o e uso de seus recursos h?dricos. Este trabalho objetivou a elabora??o de estudo sobre o comportamento do fluxo de sedimentos em suspens?o ao longo da Bacia do Rio S?o Francisco Falso. Com base nos dados hidrossedimentom?tricos, foram geradas curvas-chave de concentra??o de sedimentos e vaz?o; leitura do turbid?metro e vaz?o; leitura do turbid?metro e concentra??o de sedimento, e, posteriormente, os valores de medi??es das vaz?es di?rias foram convertidos em valores de descarga s?lida em suspens?o. A esta??o da bacia apresentou vaz?o m?dia di?ria de 4,81 m?/s e um fluxo m?dio de sedimentos em suspens?o de aproximadamente 7,23 t.dia?־, o que corresponde a um valor de descarga s?lida espec?fica em suspens?o de 5 t.ano?־.km?. Tamb?m foi elaborada a caracteriza??o fisiogr?fica da Bacia do Rio S?o Francisco Falso.
6

Estudos hidrossedimentológicos e de qualidade de água no Rio Piquiri

Angst, Fernando 24 July 2009 (has links)
Made available in DSpace on 2017-07-10T19:24:32Z (GMT). No. of bitstreams: 1 Fernando Angst.pdf: 528085 bytes, checksum: f19a7881a5eab1694c71c711eacf7b5b (MD5) Previous issue date: 2009-07-24 / The objective of this paper was to evaluate the hidrossedimentologic parameters, evaluate the hidrologic dates of the ANA (National Agency of the Waters) and the parameters physic-chemical of the water of the station Bridge of Piquiri, and relating them to the systems of the soil use of the basin. They were monitored the parameters of the flood, concentration of suspention sediments and the water quality parameters, total nitrogen, nitrite, nitrate, phosphorus, pH, turbidity and electrical condutivicty, during the period of August of 2007 to April of 2008 in the station Bridge of Piquiri, town of Ubiratã, BR-369. They determined the rating curve of flood (R2=0,99), concentration of suspension sediment (R2=0,95), total day discharge of sediments (R2=0,98) and turbidity in function of suspension sediments (R2=0,94), being that all presented good settlements. The results indicated that can be classified in a very decrease it moderated the output of sediments of the basin. It analyzes of the river discharge established by the ANA showed variations of flood when compared to the values of the present study. The analysis of the suspention sediments concentration of the ANA data series showed a settlement very under its correlation. The physical analysis indicated a good quality of water of the basin, therefore the parameters did not surpass the limits established by the Resolution CONAMA no 357/05. It is able to conclude that the basin finds-itself in satisfactory environmental conditions and that the conservation approaches of use of soil employees in the basin contribute for the maintenance of the quality of the water. / O objetivo deste trabalho foi avaliar os parâmetros hidrossedimentológicos, avaliar os dados hidrológicos da Agência Nacional das Águas (ANA) e os parâmetros físico-químicos da água da estação Ponte do Piquiri, relacionandoos aos sistemas de uso do solo da bacia. Foram monitorados os parâmetros de vazão do rio, concentração de sedimentos em suspensão e os parâmetros de qualidade de água, nitrogênio total, nitrito, nitrato, fósforo, pH, turbidez e condutividade elétrica durante o período de Agosto de 2007 a Abril de 2008 na estação Ponte do Piquiri, município de Ubiratã, BR-369. Determinaram-se as curvas-chave de vazão (R2=0,99), concentração de sedimentos em suspensão (R2=0,95), carga total diária de sedimentos (R2=0,98) e turbidez em função de sedimentos em suspensão (R2=0,94), sendo que todas apresentaram bons ajustes. Os resultados indicaram que pode ser classificada em muito baixa a moderada a produção de sedimentos da bacia. A análise das vazões estabelecidas pela ANA demonstraram variações de volume quando comparadas aos valores do presente estudo. A análise dos dados de concentração de sedimentos em suspensão da série da ANA demonstrou um ajuste muito baixo de sua correlação. A análise físico-química indicou uma boa qualidade de água da bacia, pois os parâmetros não ultrapassaram os limites estabelecidos pela Resolução 357/2005 CONAMA para rios de Classe II. Pode-se concluir que a bacia encontra-se em condições ambientais satisfatórias e que os métodos conservacionistas de uso do solo empregados na bacia contribuem para a manutenção da qualidade da água.
7

Curva chave para o monitoramento automático de sedimentos na Bacia do Rio São Francisco Falso - PR / Rating curve for automatic monitorament of sediments in basin of the False San Francisco River - PR.

Poletto, Kayla Walquiria Garmus 04 April 2008 (has links)
Made available in DSpace on 2017-05-12T14:47:18Z (GMT). No. of bitstreams: 1 Kayla Walquiria Garmus Poletto.pdf: 11373984 bytes, checksum: 4001fb7e0acd1d130237b83ee319f68d (MD5) Previous issue date: 2008-04-04 / Knowledge of the hydro-sedimentologic behavior of a river basin is basic for the appropriate management and use of their water resources. This work objectified to implement a study about the behavior of suspended-sediment discharge along the basin of false San Francisco River. Based on the available hydrosedimentometric data, had been generated rating-curve of the sediments concentration and outflow; reading of turbid?metro and outflow; reading of turbid?metro and concentration of sediment, and, afterwards, the measurements values of the daily outflow were converted into suspended-sediments discharge. The station of the basin presented daily average outflow of 4,81 m?/s an average suspended-sediment flow about 7,23 ton.day ?־, what it corresponds to a value of a specific suspended sediment load de 5 t.ano?־.km?. Also the physiographic characterization of the Basin of the False San Francisco River. / O conhecimento do comportamento hidrossedimentol?gico de uma bacia hidrogr?fica ? fundamental para a adequada gest?o e uso de seus recursos h?dricos. Este trabalho objetivou a elabora??o de estudo sobre o comportamento do fluxo de sedimentos em suspens?o ao longo da Bacia do Rio S?o Francisco Falso. Com base nos dados hidrossedimentom?tricos, foram geradas curvas-chave de concentra??o de sedimentos e vaz?o; leitura do turbid?metro e vaz?o; leitura do turbid?metro e concentra??o de sedimento, e, posteriormente, os valores de medi??es das vaz?es di?rias foram convertidos em valores de descarga s?lida em suspens?o. A esta??o da bacia apresentou vaz?o m?dia di?ria de 4,81 m?/s e um fluxo m?dio de sedimentos em suspens?o de aproximadamente 7,23 t.dia?־, o que corresponde a um valor de descarga s?lida espec?fica em suspens?o de 5 t.ano?־.km?. Tamb?m foi elaborada a caracteriza??o fisiogr?fica da Bacia do Rio S?o Francisco Falso.
8

Estudos hidrossedimentológicos e de qualidade de água no Rio Piquiri

Angst, Fernando 24 July 2009 (has links)
Made available in DSpace on 2017-05-12T14:47:52Z (GMT). No. of bitstreams: 1 Fernando Angst.pdf: 528085 bytes, checksum: f19a7881a5eab1694c71c711eacf7b5b (MD5) Previous issue date: 2009-07-24 / The objective of this paper was to evaluate the hidrossedimentologic parameters, evaluate the hidrologic dates of the ANA (National Agency of the Waters) and the parameters physic-chemical of the water of the station Bridge of Piquiri, and relating them to the systems of the soil use of the basin. They were monitored the parameters of the flood, concentration of suspention sediments and the water quality parameters, total nitrogen, nitrite, nitrate, phosphorus, pH, turbidity and electrical condutivicty, during the period of August of 2007 to April of 2008 in the station Bridge of Piquiri, town of Ubiratã, BR-369. They determined the rating curve of flood (R2=0,99), concentration of suspension sediment (R2=0,95), total day discharge of sediments (R2=0,98) and turbidity in function of suspension sediments (R2=0,94), being that all presented good settlements. The results indicated that can be classified in a very decrease it moderated the output of sediments of the basin. It analyzes of the river discharge established by the ANA showed variations of flood when compared to the values of the present study. The analysis of the suspention sediments concentration of the ANA data series showed a settlement very under its correlation. The physical analysis indicated a good quality of water of the basin, therefore the parameters did not surpass the limits established by the Resolution CONAMA no 357/05. It is able to conclude that the basin finds-itself in satisfactory environmental conditions and that the conservation approaches of use of soil employees in the basin contribute for the maintenance of the quality of the water. / O objetivo deste trabalho foi avaliar os parâmetros hidrossedimentológicos, avaliar os dados hidrológicos da Agência Nacional das Águas (ANA) e os parâmetros físico-químicos da água da estação Ponte do Piquiri, relacionandoos aos sistemas de uso do solo da bacia. Foram monitorados os parâmetros de vazão do rio, concentração de sedimentos em suspensão e os parâmetros de qualidade de água, nitrogênio total, nitrito, nitrato, fósforo, pH, turbidez e condutividade elétrica durante o período de Agosto de 2007 a Abril de 2008 na estação Ponte do Piquiri, município de Ubiratã, BR-369. Determinaram-se as curvas-chave de vazão (R2=0,99), concentração de sedimentos em suspensão (R2=0,95), carga total diária de sedimentos (R2=0,98) e turbidez em função de sedimentos em suspensão (R2=0,94), sendo que todas apresentaram bons ajustes. Os resultados indicaram que pode ser classificada em muito baixa a moderada a produção de sedimentos da bacia. A análise das vazões estabelecidas pela ANA demonstraram variações de volume quando comparadas aos valores do presente estudo. A análise dos dados de concentração de sedimentos em suspensão da série da ANA demonstrou um ajuste muito baixo de sua correlação. A análise físico-química indicou uma boa qualidade de água da bacia, pois os parâmetros não ultrapassaram os limites estabelecidos pela Resolução 357/2005 CONAMA para rios de Classe II. Pode-se concluir que a bacia encontra-se em condições ambientais satisfatórias e que os métodos conservacionistas de uso do solo empregados na bacia contribuem para a manutenção da qualidade da água.
9

Power V. Threhsold: Near-Channel Morphology Controls Sediment Rating Curve Shape in Coastal Redwood Watersheds

Fisher, Adam Caspian Nebraska 01 December 2019 (has links)
River sediment is one of the most pervasive pollutants in the world. Excess amounts of fine sediment can reduce water quality, damage stream ecosystems, and harm aquatic life. Both natural and human-caused processes can add sediment to a river, such as tectonic uplift, landslides, and timber harvesting. Therefore, it is important to understand how fine sediment enters and moves through a rive system to inform policymakers and land-managers on effective ecosystem management. In this study, we determined how the relationship between river flow and suspended sediment changed among watersheds along the North Coast of California. We found a rise in suspended sediment concentration at median flows following extreme timber harvesting. Additionally, our results indicate that river flow and suspended sediment relationships are influenced by timber harvest activity, tectonic uplift, rainfall patterns, and near-channel environments. These results support previous findings that extreme land disturbance in a watershed, be it natural or human-caused, can change river flow and suspended sediment relationships. Our results suggest that policymakers and land-managers should take into account tectonic uplift when making regulation and should prioritize protecting near-channel environments.
10

Probabilistic Estimation of River Discharge Considering Channel Characteristics Uncertainty with Particle Filters / 河道特性の不確定性を考慮した粒子フィルターによる河川流量の確率的推定

Kim, Yeonsu 24 September 2013 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第17869号 / 工博第3778号 / 新制||工||1578(附属図書館) / 30689 / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 寶 馨, 教授 細田 尚, 准教授 立川 康人 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

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