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Academic literature on the topic 'Drainage models'

Author: Grafiati
Published: 10 December 2022
Last updated: 28 January 2023

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Journal articles on the topic "Drainage models"

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Yang, Song-Yue, Che-Hao Chang, Chih-Tsung Hsu, and Shiang-Jen Wu. "Variation of uncertainty of drainage density in flood hazard mapping assessment with coupled 1D–2D hydrodynamics model." Natural Hazards 111, no. 3 (January 19, 2022): 2297–315. http://dx.doi.org/10.1007/s11069-021-05138-1.

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AbstractCoupled 1D–2D hydrodynamic models are widely utilized in flood hazard mapping. Previous studies adopted conceptual hydrological models or 1D hydrodynamic models to evaluate the impact of drainage density on river flow. However, the drainage density affects not only river flow, but also the flooded area and location. Therefore, this work adopts the 1D–2D model SOBEK to investigate the impact of drainage density on river flow. The uncertainty of drainage density in flood hazard mapping is assessed by a designed case and a real case, Yanshuixi Drainage in Tainan, Taiwan. Analytical results indicate that under the same return period rainfall, reduction in tributary drainages in a model (indicating a lower drainage density) results in an underestimate of the flooded area in tributary drainages. This underestimate causes higher peak discharges and total volume of discharges in the drainages, leading to flooding in certain downstream reaches, thereby overestimating the flooded area. The uncertainty of drainage density decreases with increased rainfall. We suggest that modeling flood hazard mapping with low return period rainfalls requires tributary drainages. For extreme rainfall events, a lower drainage density could be selected, but the drainage density of local key areas should be raised.
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Yen, B. C. "Urban drainage models." Eos, Transactions American Geophysical Union 67, no. 45 (1986): 1309. http://dx.doi.org/10.1029/eo067i045p01309-02.

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Anonymous. "Urban drainage models." Eos, Transactions American Geophysical Union 66, no. 7 (1985): 59. http://dx.doi.org/10.1029/eo066i007p00059-08.

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Sun, H., and P. S. Cornish. "A catchment-based approach to recharge estimation in the Liverpool Plains, NSW, Australia." Australian Journal of Agricultural Research 57, no. 3 (2006): 309. http://dx.doi.org/10.1071/ar04015.

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This study investigated drainage and shallow groundwater change in a headwater catchment of the Liverpool Plains in north-western New South Wales. A catchment model, SWAT (Soil and Water Assessment Tool), was used to explore rain-fed drainage to shallow groundwater and its relationship to land use. Drainage was predicted along with the prediction of runoff on a catchment and land-use basis over a simulation period of 44 years. Predicted drainage in the catchment was 8 mm/year for the 44 years, which essentially matched estimates derived from bore data observed in the catchment over a 22-year period. These estimates of drainage are much lower than published estimates based on scaling up to the catchment using estimates of drainage derived from point-scale models for different land uses. Estimates of drainage for the different land uses, derived from the catchment model, were also generally lower than simulated drainages from other studies in the area using point-scale models. The investigation demonstrates a place for catchment-based modelling for estimating drainage at the catchment scale. This is mainly because observed catchment runoff is used as an error controller in catchment recharge modelling, whereas scaled-up point-scale modelling generally does not use observed catchment runoff to derive the catchment drainage. Modelling on the Liverpool Plains catchment also suggests that some of the drainage entering the vadose zone and groundwater is later lost via evapotranspiration, a process not generally simulated in crop models, and requiring further investigation to improve understanding of recharge processes and accuracy of modelling.
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Kostova, Irina, and Ivanka Todorova. "Pentachlorophenol degradation in landfill drainage models." Waste Management & Research 18, no. 6 (December 2000): 567–71. http://dx.doi.org/10.1177/0734242x0001800607.

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Deletic, A., C. B. S. Dotto, D. T. McCarthy, M. Kleidorfer, G. Freni, G. Mannina, M. Uhl, et al. "Assessing uncertainties in urban drainage models." Physics and Chemistry of the Earth, Parts A/B/C 42-44 (January 2012): 3–10. http://dx.doi.org/10.1016/j.pce.2011.04.007.

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Kostova, Irina, and Ivanka Todorova. "Pentachlorophenol degradation in landfill drainage models." Waste Management and Research 18, no. 6 (December 2000): 567–71. http://dx.doi.org/10.1034/j.1399-3070.2000.00164.x.

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Basinsky, A. S. "Drainage surgery for primary open-angle glaucoma: past, present, future." Fyodorov journal of ophthalmic surgery, no. 2 (July 15, 2021): 79–85. http://dx.doi.org/10.25276/0235-4160-2021-2-79-85.

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Relevance. Despite many techniques for reducing intraocular pressure, surgical treatment of glaucoma has limited effectiveness. First, due to excessive scarring of new intraocular fluid outflow pathways and second, antifibrotics medicaments are unable to effectively control wound healing. The use of drainages reduces the risk of excessive scarring in the area of the filtration pad and forms several ways of outflow of intraocular fluid. The review presents the following sections: development history, advantages, disadvantages, surgical technique and promising directions of glaucoma drainage surgery. Purpose. Summarizing data on the possibility of drainage surgery, historical aspects, causes of scarring and methods of dealing with them. Provide data on various modern drainage devices that are used not only in Russia and their effectiveness. Material and methods. To perform the review, we searched for literature sources on the abstract databases E-library, PubMed and Scopus for the period up to and including 2018, using the keywords «glaucoma drainage surgery» (in the E-library database), «anti-glaucoma drainage» and «anti-glaucoma drainage device» (in the PubMed and Scopus databases). Abstracts of conferences were excluded from the review. A total of 40 articles related to the review topic were identified. The beginning of publications on this issue in domestic sources dates back to 1970, and in foreign sources to 1987. Results. The review presents the history of development, advantages, disadvantages of surgical techniques and promising areas of glaucoma drainage surgery. Various models of drainage devices, as well as their specific and non-specific complications are described. The effectivenes of various valves were 70%, with an average decrease in the level of IOP by at least 50% from the preoperative values. At the same time, the risk of an increase in the level of IOP above the target values is about 10% per year, which leads to the fact that after 5 years only in 50% of cases drainage devices function effectively. Therefore, studies of biomaterials, forms and techniques of drainage implantation surgery, new controlled-release antifibrotic drugs can positively affect the long-term effectiveness of glaucoma surgery. Conclusion. The data presented in the literature review allow us to identify the most effective models of drainage devices, their effectiveness, implantation techniques and possible complications. Key words: glaucoma, refractory glaucoma, glaucoma drainage surgery, drainages.
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El-Sadek, Alaa, Jan Feyen, and Jean Berlamont. "Comparison of Models for Computing Drainage Discharge." Journal of Irrigation and Drainage Engineering 127, no. 6 (December 2001): 363–69. http://dx.doi.org/10.1061/(asce)0733-9437(2001)127:6(363).

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Fairfield, John, and Pierre Leymarie. "Drainage networks from grid digital elevation models." Water Resources Research 27, no. 5 (May 1991): 709–17. http://dx.doi.org/10.1029/90wr02658.

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Dissertations / Theses on the topic "Drainage models"

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Madramootoo, Chandra Alastair 1954. "An agricultural land drainage simulation model /." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=72017.

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A deterministic computer model was developed to continuously simulate the runoff from surface and subsurface-drained fields in the St. Lawrence lowlands. The model simulates all of the major hydrologic and hydraulic processes occurring both above and below the ground. Input data requirements include hourly rainfall, daily potential evapotranspiration, soil physical properties, field dimensions, open channel geometry and drainage system specifications.
Events for the years 1978 to 1982 were simulated, to compare the runoff characteristics between 20 ha, clay loam, surface-drained and subsurface-drained fields. Further simulations were conducted to examine the hydrologic effects of wide-spaced, deep, parallel field ditches.
Hydrographs for the one-in-200-year storm were also simulated. All of the simulations confirmed that the peak flow rate on the subsurface-drained field was less than that of the surface-drained field. Longer times to peak and lag times occurred on the subsurface-drained field.
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Wu, Guangxi. "Sensitivity and uncertainty analysis of subsurface drainage design." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28529.

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Literature on subsurface drainage theories, determination of drainage parameters, and analysis approaches of uncertainty was reviewed. Sensitivity analysis was carried out on drain spacing equations for steady state and nonsteady state, in homogeneous soils and in layered soils. It was found that drain spacing is very sensitive to the hydraulic conductivity, the drainage coefficient, and the design midspan water table height. Spacing is not sensitive to the depth of the impermeable layer and the drain radius. In transient state, spacing is extremely sensitive to the midspan water table heights if the water table fall is relatively small. In that case steady state theory will yield more reliable results and its use is recommended. Drain spacing is usually more sensitive to the hydraulic conductivity of the soil below the drains than to that of the soil above the drains. Therefore, it is desirable to take samples from deeper soil when measuring hydraulic conductivity. A new spacing formula was developed for two-layered soils and a special case of three-layered soils with drains at the interface of the top two layers. This equation was compared with the Kirkham equation. The new formula yields spacings close to the Kirkham equation if the hydraulic conductivity of the soil above the drains is relatively small; otherwise, it tends to give more accurate results. First and second order analysis methods were employed to analyze parameter uncertainty in subsurface drainage design. It was found that conventional design methods based on a deterministic framework may result in inadequate spacing due to the uncertainty involved. Uncertainty may be incorporated into practical design by using the simple equations and graphs presented in this research; the procedure was illustrated through an example. Conclusions were drawn from the present study and recommendations were made for future research.
Applied Science, Faculty of
Graduate
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Mercurio, Matthew Forrest. "Divider analysis of drainage divides delineated at the field scale." Virtual Press, 2004. http://liblink.bsu.edu/uhtbin/catkey/1306855.

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Previous works have applied the Divider Method to the shapes of drainage divides as measured from maps. This study focuses on the shapes of several drainage divides measured in the field at very fine scale. These divides, chosen for their sharp crests, include portions of the Continental Divide in Colorado and badlands-type divides in Arizona, Wyoming, South Dakota, and Texas. The badlands type divides were delineated using a laser theodolite to collect data at decimeter point spacing, and the Continental Divide segments were delineated using pace and bearing at a constant point spacing of 30 meters. A GIS was used to store and visualize the divide data, and an automated divider analysis was performed for each of the 16 drainage divides.The Richardson plots produced for each of the drainage divide datasets were visually inspected for portions of linearity. Fractal dimensions (D) were calculated using linear regression techniques for each of the linear segments identified in the Richardson plots. Six of the plots exhibited two distinct segments of linearity, nine plots exhibited one segment, and one plot exhibited no segments of linearity. Residual analyses of the trend lines show that about half of the Richardson plot segments used to calculate D exhibit slight curvature. While these segments are not strictly linear, linear models and associated D values may still serve well as approximations to describe degree of divide wandering.Most (20 out of 21) of the dimensions derived from the Richardson plots for the drainage divides fall within the range from 1.01-1.07. The D values calculated for the Continental Divide range from 1.02-1.07. The dimensions calculated for the badlandtype divides were distributed evenly across the range of 1.01-1.06, with a single exceptional D value at 1.12. Only four of the divide D values fall within a range of 1.06–1.12, the range for D established for drainage divides in published map-based studies, despite the apparent dominance of erosion processes on the measured divides.
Department of Geology
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Kalliokoski, J. (Juha). "Models of filtration curve as a part of pulp drainage analyzers." Doctoral thesis, Oulun yliopisto, 2011. http://urn.fi/urn:isbn:9789514294273.

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Abstract The filtration of pulp suspension is one of the key papermaking processes. It is measured using many kinds of analyzers and modeled using both physical and empirical mathematical expressions. The main target of this thesis was to develop an empirical mathematical model to describe the filtration of a drainage analyzer. In this work the diameter of the screen (10 cm), as well as the amount (1000 cm3), consistency (0.3%) and temperature (20 ˚C) of the sample were (about) the same as those of the Canadian Standard Freeness analyzer. The analyzer was equipped with the measurements of filtrated volume, driving pressure and filtrate consistency. The pressures from the underpressure of 80 kPa to the overpressure of 80 kPa could be used. Pulp types of SGW, PGW, TMP and chemical pulp with freeness levels from 30 to 600 ml were analyzed. A conditioner of the sample volume, temperature and consistency measurements was constructed. The error of freeness value caused by the errors of the conditioner was evaluated to be less than 1%. The equations for the calculation of the possible initial values of the controlled quantities were derived. The optically measured consistencies of the filtrates were different for different pulp types and decreased close to zero before the filtrated volume of 150 cm3. The filtration seemed to change the portion of optically active fines. In the model of this work the filtration time (t) is proportional to an experimental power of the filtrated volume (V): Ve = kt. An auxiliary constant (Ve = kt + V0e) was used during the regression analyses to overcome the disturbances and non-validity of the model in the beginning of the filtration. The correlation coefficients of the fit were higher than 0.999. The exponent 2 suggested by Darcy’s law is a special case while the exponent has also been close to 1 or 3. The curves of specific filtration resistances, based on the model and pressure measurements, were shown to change during the course of drainage and as a function of pressure additionally dependent on the pulp type. The model was successfully used to calculate freeness values and to filter noise from the measurements
Tiivistelmä Paperimassasulpun suotauttaminen on paperinvalmistuksen avainprosesseja. Sitä on mitattu monenlaisilla analysaattoreilla ja kuvattu sekä fysikaalisilla että kokeellisilla matemaattisilla malleilla. Tämän tutkimuksen päätavoite on kehittää suotautuvuusanalysaattorin kokeellista matemaattista mallia. Tutkimuksessa viiran halkaisija (10 cm) sekä näytteen määrä (1000 cm3), sakeus (0.3 %) ja lämpötila (20 ˚C) olivat suunnilleen samat kuin Canadian standard freeness –analysaattorissa. Järjestelmä mittasi suotautettua tilavuutta, suotauttavaa painetta ja suodoksen sakeutta. Suotautuspaineet olivat 80 kPa:n ali- ja ylipaineen väliltä. Testattavana oli hioketta, painehioketta ja termohierrettä sekä kemiallista massaa, joiden freeness oli 30 ml:sta 600 ml:aan. Analysaattoriin rakennettu vakiointijärjestelmä sääti näytteen sakeuden, tilavuuden ja lämpötilan niin tarkasti halutuiksi, että näiden vaihtelu ei olisi muuttanut freeness-arvoa edes prosenttia. Suureiden kehittymiselle johdettiin kaavat. Niiden avulla voidaan laskea ne näytteen arvoalueet, joilta halutut tavoitearvot voidaan saavuttaa. Optisesti mitattu suodoksen sakeus riippui massatyypistä ja hiipui lähes nollaksi ennen kuin 150 ml oli suotautettu. Suotautus muutti optisesti aktiivisen hienoaineen osuutta. Tämän työn suodoskäyrän mallissa aika (t) on verrannollinen suotautetun tilavuuden (V) kokeellisen potenssiin: Ve = kt. Mallinnuksen ajaksi lisätään apuparametri (Ve = kt+V0e), jotta suotautuksen alku ei huononna mallia. Sovituksen korrelaatiokerroin oli yli 0.999. Eksponentin arvo vaihteli vähän yli yhdestä melkein kolmeen, joten Darcyn lain mukainen eksponentin arvo 2 osoittautui erikoistapaukseksi. Mallin ja painemittauksen avulla lasketut ominaisresistanssit muuttuivat suotautuksen kuluessa ja riippuivat myös massatyypistä. Mallin avulla voitiin laskea näytteen freeness sekä suodattaa mittauskohinaa
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Freitas, Henrique Rennó de Azeredo. "Drainage networks and watersheds delineation derived from TIN-based digital elevation models." Instituto Nacional de Pesquisas Espaciais (INPE), 2014. http://urlib.net/sid.inpe.br/plutao/2014/11.16.19.25.

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Digital Elevation Models (DEMs) are objects of great importance in many studies of natural sciences and one relevant area of their application is hydrology, as from a DEM it is possible to generate drainage networks and watersheds, which are essential elements in the understanding of hydrological processes. All the methods developed to generate drainage networks from a DEM depend on its representation and the most common representation is given by regular grids, where elevation values are assigned to cells uniformly distributed over space. However, this representation presents limitations in the flow directions, which are defined in only eight distinct directions. This work considers the terrain model given by a Triangulated Irregular Network (TIN) generated from contour lines and sampled points, where the terrain surface is modeled by several triangles defined from a set of points adequately distributed over space, so that the TIN can efficiently adapt to its irregularities. In addition, flow directions on TINs encompass a11 the possible directions and depend on the slope of the triangles, so this structure is more flexible regarding the calculation of water flows. The triangulation used in this work is the constrained Delaunay triangulation and the method that generates drainage networks considers flow directions given by the gradient of the plane defined from each triangle. Problems that commonly occur in DEMs such as flat areas and pits, which create inconsistencies in the terrain model and discontinuities in flows, also deserve special attention. In the present work, flat areas are removed by the insertion of new points into the triangulation with interpolated elevation values and pits by the definition of paths of points starting from the pit until reaching another point of lower elevation, where all these points have their elevation values re-interpolated. Most importantly, this work describes a methodology for calculating drainage paths from a TIN traced by processing the triangles with an associated priority and then connected defining a drainage graph structure, which is proposed in this work for the calculation of accumulated flows. Afterwards, drainage networks are generated according to given threshold values and watersheds are then delineated from the drainage networks. A11 the results from the TIN are qualitatively compared to regular grid results generated with the TerraHidro computational platform developed at INPE and also to an available drainage network produced by specialists and considered here as a reference of the main courses of water over the terrain. Results are very promising showing that TIN terrain models can be used to generate drainage networks from accumulated flows consistent with real-world hydrological patterns.
Modelos Digitais de Elevação (MDEs) são objetos de grande importância em muitos estudos das ciências naturais e uma área relevante de sua aplicação é a hidrologia, pois a partir de um MDE é possível gerar redes de drenagem e bacias hidrográficas, as quais são elementos essenciais no entendimento de processos hidrológicos. Todos os métodos desenvolvidos para gerar redes de drenagem a partir de um MDE dependem da sua representação e a representação mais comum é dada por grades regulares, onde valores de elevação são atribuídos em células uniformemente distribuídas no espaço. Entretanto, essa representação apresenta limitações nas direções de fluxo, as quais são definidas em apenas oito direções distintas. Este trabalho considera o modelo de terreno dado por uma Rede Triangular Irregular (Triangulated Irregular Network ou TIN) gerada de curvas de nível e pontos amestrados, onde a superfície do terreno é modelada por vários triângulos definidos a partir de um conjunto de pontos adequadamente distribuídos no espaço, de forma que o TIN pode eficientemente se adaptar as suas irregularidades. Além disso, direções de fluxo sobre TINs abrangem todas as direções possíveis e dependem da declividade dos triângulos, de modo que essa estrutura é mais flexível ao se considerar o cálculo dos fluxos de água. A triangulação utilizada neste trabalho é a triangulação de Delaunay restrita e o método que gera redes de drenagem considera direções de fluxo dadas pelo gradiente do plano definido por cada triângulo. Problemas que comumente ocorrem em MDEs tais como áreas planas e fossos, os quais criam inconsistências no modelo de terreno e descontinuidades nos fluxos, também merecem atenção especial. No presente trabalho, áreas planas são removidas pela inserção de novos pontos na triangulação com valores de elevação interpolados e fossos pela definição de caminhos de pontos iniciando do fosso até alcançar um outro ponto de menor elevação, onde todos esses pontos têm seus valores de elevação reinterpolados. Sobretudo, este trabalho descreve uma metodologia para calcular caminhos de drenagem a partir de um TIN traçados ao processar os triângulos com uma prioridade associada e depois conectados definindo uma estrutura de grafo de drenagem, a qual é proposta neste trabalho para o cálculo de fluxos acumulados. Posteriormente, redes de drenagem são geradas de acordo com determinado ti valores ele limiar e bacias hidrográficas são então delimitadas a partir das redes de drenagem. Todos os resultados do TIN são comparados qualitativamente a resultados de grade regular gerados com a plataforma computacional TerraHidro desenvolvida no INPE e também a uma rede de drenagem disponível, produzida por especialistas e considerada aqui como uma referência dos principais cursos d'água no terreno. Os resultados são bastante promissores mostrando que modelos de terreno TIN podem ser utilizados para gerar redes de drenagem a partir de fluxos acumulados consistentes com padrões hidrológicos reais.
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Richard, Paul François. "A computer analysis of the flow of water and nutrients in agricultural soils as affected by subsurface drainage." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/29171.

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A computer model was developed in order to determine the effects of drainage practices on nutrient losses from level agricultural soils. The model performs a daily simulation of the vertical flow of water, nitrogen, phosphorus, and heat, and of the growth of crops. A water flow submodel calculates the depth of the water table based on daily predictions of evaporation, transpiration, flow to drains and ditches, and deep percolation. An original saturated-unsaturated flow algorithm is used to determine moisture infiltration, redistribution, and upward flow in the soil matrix, as well as bypassing flow in the soil macropores and horizontal flux between the soil matrix and the macropores, and surface runoff. Nutrient movement occurs by mass flow. Heat flow, nutrient biochemical transformations, and crop growth are determined by using well established relations. Field tests were carried out for a period of two years on an experimental site in the Lower Fraser Valley of British Columbia. The water table depth was measured on a continuous basis. Grab samples of drainwater and observation wells were obtained periodically and analyzed for nitrogen (N0₃-N, NH₄-N, and TKN) and phosphorus (P0₄-P and TP). The field results show a decrease in the concentration of all nutrients over the sampling period, and provide evidence that denitrification and bypassing flow are important mechanisms affecting the nutrient balance of this soil. These results were used to calibrate the model. An excellent fit of the observed water table profile and an adequate fit of the observed drain concentration of nitrate were obtained. The simulation revealed that bypassing flow is a very important transfer mechanism in this soil and must be included in order to obtain a satisfactory fit of the experimental data. A sensitivity analysis of the model showed that the patterns of moisture flow have a predominant influence on the rate of nutrient leaching. In particular, it was found that the nutrient concentration in drain water is a strong function of the hydraulic conductivity of the soil matrix and of the horizontal distance between the soil macropores, which control the ratio of moisture flow in the soil matrix to the macropore flow and the lateral diffusion of nutrients between the soil matrix and the macropores. The effects of four different drainage designs on nutrient losses were simulated over a period of two years for three different soils and two different nutrient distributions in the soil. It was found that there is a large difference between the amount of nutrients leached from drainage systems using different drainage coefficients. There was also a large difference in the response of two drainage designs based on the same drainage coefficient but using different depth and spacing of drains. Transient effects, as determined by the initial vertical distribution of the nutrients, were seen to remain dominant over the two year duration of the simulation. The model was found to be useful in explaining the apparent contradictions found in the literature assessing the effects of subsurface drainage on nutrient losses. The results from the model show these effects to be strongly site and condition specific. Furthermore, the model shows that soils and drainage designs that produce similar volumes of drain flow may exhibit very different leaching responses, and that drainage designs equivalent from a hydraulic standpoint can be very dissimilar in their potential for leaching nutrients. The model provides a tool which can be used to determine the appropriateness of different drainage designs in soils where minimizing nutrient losses is critical.
Science, Faculty of
Resources, Environment and Sustainability (IRES), Institute for
Graduate
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Samsudin, A. B. "An assessment of flow and pressure control in experimental models of glaucoma drainage surgery." Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1435420/.

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There are a number of surgical methods for treating glaucoma, including trabeculectomy and the insertion of drainage devices. At the current time, these procedures are still associated with post-operative problems for a significant number of patients, particularly with the control of aqueous humour flow and pressure e.g. hypotony. The main aim of this work was to look at ways of improving the outcomes of the procedures. The usual approach in assessing surgical techniques is to test them on live human or animal eyes. This is inherently complex, with a significant challenge to keep some of the major parameters e.g. aqueous humour inflow and wound healing consistent throughout a series of tests, and with this the problem of reproducibility. The approach used in this work includes a review and analysis of the different surgical methods and devices from an engineering perspective, the use of scaling analysis and a large-scale physical model coupled with image processing to study trabeculectomy scleral flap characteristics and its effect on flow and pressure, and also the use of model drainage devices in ex vivo settings to look at flow and pressure. For each experiment, implications for clinical practice are discussed. Applying engineering principles to glaucoma procedures and devices provided novel insight into their functions. It was found that the trabeculectomy scleral flap acts as a valve to guard from excessive aqueous humour outflow and low pressures, and parameters such as the number and position of sutures and scleral flap geometry can be tailored to alter aqueous humour outflow. Additionally, 50 μm internal diameter tubes show promise for controlled aqueous humour flow into the subconjunctival space with avoidance of low pressures. Engineering methodology can be used in the development of new treatments and devices. However, some results may not translate exactly into the more complex living eye.
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Leandro, Jorge. "Advanced modelling of flooding in urban areas : integrated 1D/1D and 1D/2D models." Thesis, University of Exeter, 2008. http://hdl.handle.net/10036/41949.

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The research presented in this Thesis aims at defining the strengths and weaknesses of an Improved 1D/1D model when compared with a more accurate 1D/2D model. Although both coupled-models (sewer/surface) solve the St.\ Venant equations in both layers, the latter uses a higher approximation (2D two-dimensional) on the surface layer. Consequently, the 1D/1D model is computationally more efficient when compared to the 1D/2D model, however there is some compromise with the overall accuracy. The hypothesis is that "The inundation extent of urban flooding can be reproduced by 1D/1D models in good agreement with the 1D/2D models if the results are kept within certain limits of resolution and under certain conditions". The Thesis starts by investigating ways of improving an existing 1D/1D model to rival the more accurate 1D/2D model. Parts of the 1D/1D model code are changed and new algorithms and routines implemented. An innovative GIS tool translates the 1D output-results into 2D flood-inundation-maps enabling a thorough comparison between the two models. The methodology assures the set-up of two equivalent models, which includes a novel algorithm for calibrating the 1D/1D model vs.\ the 1D/2D model results. Developments are tested in two distinctly different case studies of areas prone to flooding. The conclusion is that the 1D/1D model is able to simulate flooding in good agreement with the 1D/2D model; however, it is found that features such as topography, density of the urbanised areas and rainfall distribution may affect the agreement between both models. The work presented herein is a step forward in understanding the modelling capabilities of the analysed coupled-models, and to some extent may be extrapolated to other models. Research is growing in urban flooding and this work may well prove to be a strong foundation basis for future research.
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Tribe, Andrea S. "Automated recognition of valley heads, valley bottoms and drainage networks from grid digital elevation models." Thesis, University of Reading, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306257.

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Hiester, Justin. "Investigations into the Regional and Local Timescale Variations of Subglacial Drainage Networks." PDXScholar, 2013. https://pdxscholar.library.pdx.edu/open_access_etds/1022.

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Subglacial water plays an important role in the regulation of an ice sheet's mass balance. It may be the dominant control on the velocities of ice streams and outlet glaciers on scales of months to millennia. Recent satellite observations of ice surface elevation changes have given researchers new insights into how subglacial water is stored and transported. Localized uplift and settling of the ice surface implies that lakes exist beneath the ice sheet that are being filled and drained on relatively short time scales. %At the base of an ice sheet water can be transported through a variety of drainage networks or stored in subglacial lakes. Here, a numerical investigation of the mechanisms of transport and storage of subglacial water and the associated time scales is presented. Experiments are carried out using a finite element model of coupled ice and water flow. The first experiment seeks to understand the relationship between the depth of a basal depression and the area over which the feature affects basal water flow. It is found that as the perturbation to a topographic depression's depth is increased, water is rerouted in response to the perturbation. Additionally it is found that the relationship between perturbation depth and the extent upstream to which its effects reach is nonlinear. The second experiment examines how the aspect ratio of bed features (prolate, oblate, or equidimensional) influences basal water flow. It is found that the systems that develop and their interactions are mediated by both the topography and the feedbacks taken into account by the coupling of the systems in the model. Features oriented parallel to ice and water flow are associated with distributed fan systems that develop branches which migrate laterally across the domain and interact with one another on monthly and yearly timescales. Laterally oriented features develop laterally extensive ponds. As the ratio of longitudinal to lateral dimension of the topography is increased, a combination of these two water distributions is seen.
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Books on the topic "Drainage models"

1

Schroeder, P. R. Verification of the lateral drainage component of the (HELP) model using physical models. Cincinnati, OH: U.S. Environmental Protection Agency, Hazardous Waste Engineering Research Laboratory, 1988.

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Budziło, Barbara. Model matematyczny poddennego korytowego ujęcia wody. Kraków: Politechnika Krakowska, 1989.

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Budziło, Barbara. Model matematyczny poddennego ujęcia wody z drenami zupełnymi i niezupełnymi. Kraków: Politechnika Krakowska, 1990.

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Sagar, B. S. Daya. Qualitative models of certain discrete natural features of drainage environment. New Delhi: Allied Publishers, 2005.

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Otwinowski, M. Scaling analysis of acid rock drainage. Ottawa, ON: CANMET, 1995.

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Carlson, E. J. Drainage from sloping land using oblique drains. Denver, Colo: Hydraulics Branch, Division of Research and Laboratory Services, Engineering and Research Center, U.S. Dept. of the Interior, Bureau of Reclamation, 1987.

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1931-, Young Robert A., and United States. Agricultural Research Service., eds. AGNPS, Agricultural Non-Point-Source Pollution Model: A watershed analysis tool. [Washington, D.C.?]: U.S. Dept. of Agriculture, Agricultural Research Service, 1987.

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Kaighn, Robert J. Verification of the pressurized flow simulation module (PFSM) of Hydra. McLean, Va: U.S. Dept. of Transportation, Federal Highway Administration, 1993.

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Hustwit, C. C. Role of oxygen transfer in acid mine drainage treatment. Washington, D.C. (810 7th St., N.W., MS#9800 Washington 20241-0001): U.S. Dept. of the Interior, Bureau of Mines, 1992.

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Hustwit, C. C. Role of oxygen transfer in acid mine drainage treatment. Washington, D.C: U.S. Dept. of the Interior, Bureau of Mines, 1992.

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Book chapters on the topic "Drainage models"

1

Wayne Skaggs, R. "Drainage Simulation Models." In Agronomy Monographs, 469–500. Madison, WI, USA: American Society of Agronomy, Crop Science Society of America, Soil Science Society of America, 2015. http://dx.doi.org/10.2134/agronmonogr38.c13.

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Sharma, Bhumika, Monica Gandhi, and Usha Yadava. "The Glaucoma Drainage Devices: Types and Models." In Glaucoma Drainage Devices, 13–17. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-5773-2_3.

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Waller, Peter, and Muluneh Yitayew. "Water and Solute Mass Balance Models." In Irrigation and Drainage Engineering, 455–74. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-05699-9_26.

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Wayne Skaggs, R., and George M. Chescheir. "Application of Drainage Simulation Models." In Agronomy Monographs, 537–64. Madison, WI, USA: American Society of Agronomy, Crop Science Society of America, Soil Science Society of America, 2015. http://dx.doi.org/10.2134/agronmonogr38.c15.

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Ali, Mohammad Javed. "Nasal Anatomy Using Realistic Anatomical Models." In Atlas of Lacrimal Drainage Disorders, 89–95. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-5616-1_7.

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Parsons, John E. "Simulation Models for Drainage Water Quality." In Agronomy Monographs, 501–35. Madison, WI, USA: American Society of Agronomy, Crop Science Society of America, Soil Science Society of America, 2015. http://dx.doi.org/10.2134/agronmonogr38.c14.

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Fassman-Beck, Elizabeth, and Firas Saleh. "Exploring Uncertainty in Uncalibrated Bioretention Models." In New Trends in Urban Drainage Modelling, 275–79. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-99867-1_46.

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Dvoriashyna, Mariia, Jan O. Pralits, Jennifer H. Tweedy, and Rodolfo Repetto. "Mathematical Models of Aqueous Production, Flow and Drainage." In Ocular Fluid Dynamics, 227–63. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-25886-3_9.

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Fua, P. "Consistent modeling of terrain and drainage using deformable models." In Lecture Notes in Computer Science, 457–74. Berlin, Heidelberg: Springer Berlin Heidelberg, 1997. http://dx.doi.org/10.1007/3-540-62909-2_97.

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Mineo, Claudio, Benedetta Moccia, Federico Lombardo, Fabio Russo, and Francesco Napolitano. "Preliminary Analysis About the Effects on the SPI Values Computed from Different Best-Fit Probability Models in Two Italian Regions." In New Trends in Urban Drainage Modelling, 958–62. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-99867-1_165.

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Conference papers on the topic "Drainage models"

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Hackett, Donna, David Crawford, John Schenk, and Mary K. Stinson. "Verification of Urban Runoff Models." In Ninth International Conference on Urban Drainage (9ICUD). Reston, VA: American Society of Civil Engineers, 2002. http://dx.doi.org/10.1061/40644(2002)124.

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Calabrò, Paolo S., and Marco Maglionico. "Comparison between a Detailed Model and Two Simplified Models in Urban Stormwater Quality Simulation." In Ninth International Conference on Urban Drainage (9ICUD). Reston, VA: American Society of Civil Engineers, 2002. http://dx.doi.org/10.1061/40644(2002)121.

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Bouteligier, Raf, Guido Vaes, and Jean Berlamont. "In Sewer Sediment and Pollutant Transport Models." In Ninth International Conference on Urban Drainage (9ICUD). Reston, VA: American Society of Civil Engineers, 2002. http://dx.doi.org/10.1061/40644(2002)111.

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Hoblit, Brian C., and David C. Curtis. "Integration of Radar Rainfall into Hydrologic Models." In Ninth International Conference on Urban Drainage (9ICUD). Reston, VA: American Society of Civil Engineers, 2002. http://dx.doi.org/10.1061/40644(2002)229.

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Vaes, Guido, Patrick Willems, and Jean Berlamont. "The Use of Reservoir Models for the Assessment of the Input from Combined Sewer Overflows into River Models." In Ninth International Conference on Urban Drainage (9ICUD). Reston, VA: American Society of Civil Engineers, 2002. http://dx.doi.org/10.1061/40644(2002)139.

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Stovin, Virginia R., John P. Grimm, Adrian P. Buxton, and Simon J. Tait. "Parametric Studies on CFD Models of Sewerage Structures." In Ninth International Conference on Urban Drainage (9ICUD). Reston, VA: American Society of Civil Engineers, 2002. http://dx.doi.org/10.1061/40644(2002)312.

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Fatemeh Samipour, Maliheh Rabie, Kourosh Mohammadi, Mohammad Hossein Mahdian, and Abd Ali Naseri. "Evaluation of Two Drainage Models in South-West Iran." In 9th International Drainage Symposium held jointly with CIGR and CSBE/SCGAB Proceedings, 13-16 June 2010, Québec City Convention Centre, Quebec City, Canada. St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2010. http://dx.doi.org/10.13031/2013.32106.

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Peng, Yao, Masa Prodanovic, and Steven Lawrence Bryant. "Improving Fidelity of Network Models for Drainage and Imbibition." In SPE Annual Technical Conference and Exhibition. Society of Petroleum Engineers, 2009. http://dx.doi.org/10.2118/124440-ms.

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Clemens, François. "Calibration and Verification of Hydrodynamic Models in Urban Drainage." In Specialty Symposium on Urban Drainage Modeling at the World Water and Environmental Resources Congress 2001. Reston, VA: American Society of Civil Engineers, 2001. http://dx.doi.org/10.1061/40583(275)7.

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LOPES, N. R., J. O. COSTA, A. M. ALMEIDA, R. D. COELHO, T. H. S. BARROS, and A. N. ALMEIDA. "DAILY REFERENCE EVAPOTRANSPIRATION ESTIMATION: COMPARING MODELS WITH DRAINAGE LYSIMETER READINGS." In IV Inovagri International Meeting. Fortaleza, Ceará, Brasil: INOVAGRI/ESALQ-USP/ABID/UFRB/INCT-EI/INCTSal/INSTITUTO FUTURE, 2017. http://dx.doi.org/10.7127/iv-inovagri-meeting-2017-res0250220.

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Reports on the topic "Drainage models"

1

Paquette, J. Digital Elevation Models for hydrological applications in Oak Ridges Moraine, southern Ontario: the necessity for structured drainage networks. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1996. http://dx.doi.org/10.4095/207889.

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Swanson, David, and Celia Hampton-Miller. Drained lakes in Bering Land Bridge National Preserve: Vegetation succession and impacts on loon habitat. National Park Service, January 2023. http://dx.doi.org/10.36967/2296593.

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The northern coastal plain of Bering Land Bridge National Preserve (BELA) lost lakes at an alarming rate over the first two decades of this century, including four lakes over 100 ha in size in 2018-2019 alone. To understand the effects of these lake drainages, we sampled vegetation of these lakes in 2019 (a reconnaissance visit) and 2021 (for the installation of permanent vegetation monitoring plots). We used these data to summarize the changes that occurred in the first three years after drainage, and to create vegetation maps from 3-m resolution satellite images coinciding with the visit dates. We used time series of these satellite images to study the rate of drainage and vegetation colonization on the lakes. We analyzed our existing data from older drained lake basins (estimated to be more than 200 years since drainage) and reviewed the literature on vegetation change in drained lakes to understand the vegetation changes that are likely in the future. Finally, we used a model of lake occupancy by loons developed by Mizel et al. (2021) to predict the effect of the 2018-2019 lake drainages on available loon habitat, using both our detailed maps of the four sampled drained lakes, and also data on all drained lakes over most of northern BELA derived from Landsat satellite images. Our results show that the four study lakes drained early in the summer, before the end of June, in 2018 (3 lakes) and 2019 (one lake). A combination of record warm weather and heavy snowfall made 2018 and 2019 especially favorable for lake drainage: thaw subsidence probably enlarged existing drainage outlet channels from the lakes, and large amounts of spring snowmelt runoff deepened the outlet channels by thermal erosion (the combination of thaw and erosion). Drainage exposed moist loamy sediment on the lake bottoms that was rapidly colonized by plants. Substantial vegetation cover developed by late summer in the same year as lake drainage in one lake, in the first post-drainage summer in a second lake, and during the 2nd year after drainage in the remaining two lakes. The first vegetation communities to develop consisted of just one or two dominant species, notably Eleocharis acicularis (spike rush), Equisetum arvense (horsetail), and/or Tephroseris palustris (mastodon flower). Other important early species were Arctophila fulva (pendant grass) and Rorippa palustris (yellow cress). By year 3, the communities had become more diverse, with significant cover by taller wetland graminoid species, including A. fulva, Eriophorum scheuchzeri, and Carex aquatilis. Frozen soil was observed in most locations on the lakes in July of 2021, suggesting that permafrost was forming on the lake bottoms. Comparison of the three-year trends in vegetation change with data from older lake basins suggest that ultimately most lake basins will develop wet tundra communities dominated by Carex aquatilis and mosses, with various low shrub species on acid, peat-dominated soils and permafrost; however, this process should take several centuries. The loon habitat model suggests that drainage essentially eliminated the potential habitat for Yellow-billed Loons on the four study lakes, because the residuals ponds were too small for Yellow-billed Loons to take flight from. A total of 17 lakes drained in northern BELA in 2018-2019. As a result, the potential Yellow-billed Loon nesting habitat in northern BELA probably decreased by approximately 2%, while habitat for Pacific Loons decreased less, by about 0.6%. Habitat for the more abundant Red-throated Loons probably increased slightly as a result of lake drainage, because of their ability to use the small residual ponds created by lake drainage.
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Rosenberg, N. D. Water drainage model. Office of Scientific and Technical Information (OSTI), September 1999. http://dx.doi.org/10.2172/14459.

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J.B. Case. WATER DRAINAGE MODEL. Office of Scientific and Technical Information (OSTI), May 2000. http://dx.doi.org/10.2172/861919.

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Turner, Adrian K. Two modes of sea-ice gravity drainage. Office of Scientific and Technical Information (OSTI), October 2012. http://dx.doi.org/10.2172/1052814.

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Couri, F. R., and H. J. Jr Ramey. A finite difference model for free surface gravity drainage. Office of Scientific and Technical Information (OSTI), September 1993. http://dx.doi.org/10.2172/10192739.

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Lambert, A., T. S. James, N. Courtier, K. Simon, M. Schmidt, C. F. M. Lewis, and A. Mainville. An improved postglacial rebound model with applications to the Nelson River drainage basin. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 2005. http://dx.doi.org/10.4095/220615.

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Tsur, Yacov, David Zilberman, Uri Shani, Amos Zemel, and David Sunding. Dynamic intraseasonal irrigation management under water scarcity, water quality, irrigation technology and environmental constraints. United States Department of Agriculture, March 2007. http://dx.doi.org/10.32747/2007.7696507.bard.

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In this project we studied optimal use and adoption of sophisticated irrigation technologies. The stated objectives in the original proposal were to develop a conceptual framework for analyzing intra-season timing of water application rates with implications for crop and irrigation technology selection. We proposed to base the analysis on an intra-seasonal, dynamic, agro-economic model of plants' water demand, paying special attention to contamination of groundwater and soil in intensively cultivated areas that increasingly rely on water of lesser quality. The framework developed in the project integrates (i) a bio-physical model of water flow in the vadose zone and water uptake by plants and yield response with (ii) a dynamic management model to determine the optimal intra-season irrigation policy. It consists of a dynamic optimization model to determine irrigation rates at each point of time during the growing season and aggregation relating harvested yield with accumulated water input. The detailed dynamic approach provides a description of yield production processes at the plant’s level, and serves to determine intra-season irrigation decisions. Data derived from extensive field experiments were used to calibrate the model's parameters. We use the framework to establish the substitution between irrigation technology (capital) and water inputs; this is an important property of irrigation water productivity that has been overlooked in the literature. Another important feature investigated is the possibility to substitute fresh and saline water with a minimal productivity loss. The effects of soil properties and crop characteristics on optimal technology adoption have also been studied. We find that sandy soil, with low water holding capacity, is more conducive to adoption of sophisticated drip irrigation, as compared to heavier soils in which drainage losses are significantly smaller.
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Steenhuis, Tammo S., Israela Ravina, Jean-Yves Parlange, Rony Wallach, and Larry D. Geohring. Improving Preferential Flow Modules by Experimentation. United States Department of Agriculture, September 1994. http://dx.doi.org/10.32747/1994.7570552.bard.

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Preferential flow is the process whereby water and solutes move by preferred pathways. During preferential flow, local wetting fronts propagate to considerable depths in the soil profile, essentially bypassing the matrix pore space. Under such conditions classical methods, such as the convective-dispersive equation, for quantifying flow of water and solutes in uniform soils are not valid. This project set out to develop methods to predict fast and early breakthrough of solutes. To facilitate understanding of these processes, several field drainage studies were conducted in the United States and Israel. In both countries, solutes moved rapidly down and could be found below 1 m depth soon after application. Based on these experiments, we developed and validated a number of modules to predict the solute concentration of the preferentially moving water in the vadose zone. We also successfully simulatd the initial high solute concentration in agriculturel tile lines shortly after the chemical was applied. The understanding gained on fast transport of agri-chemicals is instrumental in developing management practices to reduce the nonpoint sources and to increase the leaching efficiency of salt affected soils.
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Habib, Ayman, Darcy M. Bullock, Yi-Chun Lin, and Raja Manish. Road Ditch Line Mapping with Mobile LiDAR. Purdue University, 2021. http://dx.doi.org/10.5703/1288284317354.

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Maintenance of roadside ditches is important to avoid localized flooding and premature failure of pavements. Scheduling effective preventative maintenance requires mapping of the ditch profile to identify areas requiring excavation of long-term sediment accumulation. High-resolution, high-quality point clouds collected by mobile LiDAR mapping systems (MLMS) provide an opportunity for effective monitoring of roadside ditches and performing hydrological analyses. This study evaluated the applicability of mobile LiDAR for mapping roadside ditches for slope and drainage analyses. The performance of alternative MLMS units was performed. These MLMS included an unmanned ground vehicle, an unmanned aerial vehicle, a portable backpack system along with its vehicle-mounted version, a medium-grade wheel-based system, and a high-grade wheel-based system. Point cloud from all the MLMS units were in agreement in the vertical direction within the ±3 cm range for solid surfaces, such as paved roads, and ±7 cm range for surfaces with vegetation. The portable backpack system that could be carried by a surveyor or mounted on a vehicle and was the most flexible MLMS. The report concludes that due to flexibility and cost effectiveness of the portable backpack system, it is the preferred platform for mapping roadside ditches, followed by the medium-grade wheel-based system. Furthermore, a framework for ditch line characterization is proposed and tested using datasets acquired by the medium-grade wheel-based and vehicle-mounted portable systems over a state highway. An existing ground filtering approach is modified to handle variations in point density of mobile LiDAR data. Hydrological analyses, including flow direction and flow accumulation, are applied to extract the drainage network from the digital terrain model (DTM). Cross-sectional/longitudinal profiles of the ditch are automatically extracted from LiDAR data and visualized in 3D point clouds and 2D images. The slope derived from the LiDAR data was found to be very close to highway cross slope design standards of 2% on driving lanes, 4% on shoulders, as well as 6-by-1 slope for ditch lines. Potential flooded regions are identified by detecting areas with no LiDAR return and a recall score of 54% and 92% was achieved by the medium-grade wheel-based and vehicle-mounted portable systems, respectively. Furthermore, a framework for ditch line characterization is proposed and tested using datasets acquired by the medium-grade wheel-based and vehicle-mounted portable systems over a state highway. An existing ground filtering approach is modified to handle variations in point density of mobile LiDAR data. Hydrological analyses, including flow direction and flow accumulation, are applied to extract the drainage network from the digital terrain model (DTM). Cross-sectional/longitudinal profiles of the ditch are automatically extracted from LiDAR data, and visualized in 3D point clouds and 2D images. The slope derived from the LiDAR data was found to be very close to highway cross slope design standards of 2% on driving lanes, 4% on shoulder, as well as 6-by-1 slope for ditch lines. Potential flooded regions are identified by detecting areas with no LiDAR return and a recall score of 54% and 92% was achieved by the medium-grade wheel-based and vehicle-mounted portable systems, respectively.
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