• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 5
  • 5
  • 3
  • 1
  • 1
  • 1
  • Tagged with
  • 16
  • 16
  • 7
  • 5
  • 4
  • 4
  • 4
  • 4
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 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

Salinity routing in reservoir system modeling

Ha, Mi Ae 25 April 2007 (has links)
This research evaluates and improves capabilities incorporated in the Water Rights Analysis Package (WRAP) modeling system for tracking salt loads, particularly for applications dealing with natural salt pollution problems that are prevalent in several major river basins in Texas and neighboring states. WRAP is the river/reservoir system simulation model incorporated in the Water Availability Modeling (WAM) System applied by agencies and consulting firms in Texas in planning and water right regulatory activities. A salinity simulation component of WRAP called WRAP-SALT was developed recently at Texas A&M University. WRAP-SALT was based on the premise of complete mixing within the monthly computational time step. However, salt concentrations actually have time variation throughout a reservoir. This thesis research investigates more realistic salinity routing methods. Historical gauged data provide a basis for calibration of routing parameters. The timing of the inflow load to determine outflow concentration is calculated by lag parameters with the monthly time steps. Complete mixing occurs during the lag months. Two options are incorporated into WRAP-SALT for setting the lag parameter. With the first option, the model-user sets a constant that is applied during every month of the simulation. This option requires calibration studies to determine the lag. With the alternative option, a variable lag is computed within the model in each month based on the concept of retention time, which is a representation of the time required for a monthly volume of water and its salt load to flow through a reservoir. When the lag is activated, the accuracy between observed and computed mean monthly salinity concentrations through the reservoir is generally improved. The basin-wide simulation was performed for the Brazos River Basin for conditions with and without salt control dams proposed by the Corps of Engineers. The proposed salt control impoundments improve water quality throughout the basin.
2

Salinity routing in reservoir system modeling

Ha, Mi Ae 25 April 2007 (has links)
This research evaluates and improves capabilities incorporated in the Water Rights Analysis Package (WRAP) modeling system for tracking salt loads, particularly for applications dealing with natural salt pollution problems that are prevalent in several major river basins in Texas and neighboring states. WRAP is the river/reservoir system simulation model incorporated in the Water Availability Modeling (WAM) System applied by agencies and consulting firms in Texas in planning and water right regulatory activities. A salinity simulation component of WRAP called WRAP-SALT was developed recently at Texas A&M University. WRAP-SALT was based on the premise of complete mixing within the monthly computational time step. However, salt concentrations actually have time variation throughout a reservoir. This thesis research investigates more realistic salinity routing methods. Historical gauged data provide a basis for calibration of routing parameters. The timing of the inflow load to determine outflow concentration is calculated by lag parameters with the monthly time steps. Complete mixing occurs during the lag months. Two options are incorporated into WRAP-SALT for setting the lag parameter. With the first option, the model-user sets a constant that is applied during every month of the simulation. This option requires calibration studies to determine the lag. With the alternative option, a variable lag is computed within the model in each month based on the concept of retention time, which is a representation of the time required for a monthly volume of water and its salt load to flow through a reservoir. When the lag is activated, the accuracy between observed and computed mean monthly salinity concentrations through the reservoir is generally improved. The basin-wide simulation was performed for the Brazos River Basin for conditions with and without salt control dams proposed by the Corps of Engineers. The proposed salt control impoundments improve water quality throughout the basin.
3

Estudo da comunidade fitoplanctônica como bioindicador de poluição em três reservatórios em série do Parque Estadual das Fontes do Ipiranga (PEFI), São Paulo, SP / Phytoplankton community’s study as bioindicator of pollution in three cascading reservoir system in Parque Estadual das Fontes do Ipiranga (PEFI), São Paulo, SP

Lopes, Adriana Guidetti Dias 13 August 2007 (has links)
Os três reservatórios rasos e em série localizam-se no Parque Estadual das Fontes do Ipiranga (PEFI), região sudoeste do município de São Paulo, numa unidade de conservação que abriga as nascentes do histórico riacho do Ipiranga. O primeiro reservatório recebe água do Lago das Garças, um sistema artificial eutrófico, onde já foram detectadas florações de cianobactérias potencialmente tóxicas e com problemas ecológicos, sanitários e estéticos. Objetivo. Analisar a variação sazonal da comunidade fitoplanctônica de três reservatórios rasos subseqüentes a um lago hipereutrófico localizado no município de São Paulo/SP, visando avaliar a qualidade da água durante o sistema em série. Material e Métodos. As coletas foram realizadas trimensalmente durante o período de um ano (outubro/2005 a julho/2006), em uma estação de amostragem em cada um dos três reservatórios e a duas profundidades: superfície e fundo. Foram determinadas variáveis morfométricas (área superficial, perímetro, comprimento máximo e profundidade), climatológicas (temperatura do ar e precipitação), físicas e químicas (temperatura da água, transparência, zona eufótica, pH, condutividade, turbidez, oxigênio dissolvido, demanda bioquímica de oxigênio, fósforo total e ortofosfato, nitrogênio total e amoniacal), biológicas (coliformes totais e termotolerantes, clorofila-a, feofitina, composição florística, densidade total, biovolume, estimativa do número de células e espécies descritoras) e aplicações de índices biológicos. Na análise qualitativa foi empregada a rede de malha de 20 µm e identificação em microscópio óptico binocular com câmara clara. Na análise quantitativa, foi utilizado a garrafa coletora e método de sedimentação em câmara de volume definido e contagem em microscópio invertido. A ordenação dos dados foi realizada por meio da análise de componentes principais (ACP) e análise de correspondência canônica (ACC). Resultados. Como conseqüência da floração de cianobactérias registradas nos três reservatórios, foram identificados 125 táxons distribuídos em 12 classes. A classe com maior representatividade foi Chlorophyceae com 38,8%, seguida por Cyanobacteria (23,8%), Euglenophyceae (8,7%), Cryptophyceae (6,3%), Zygnemaphyceae (5,5%), Bacillariophyceae (4,7%) e 11,1% para as demais classes (Chrysophyceae, Coscinodiscophyceae, Dinophyceae, Xanthophyceae, Craspedomonadophyceae e Fragilariophyceae). Os táxons que apresentaram 100% de freqüência foram: Microcystis aeruginosa, Cylindrospermopsis raciborskii, Planktothrix agardhii (Cyanobacteria). As espécies descritoras que podem ser consideradas como bioindicadoras de poluição foram Cylindrospermopsis raciborskii e Chroococcus minutus, que juntas contribuíram com 79,4% de toda densidade deste estudo. Conclusões. A comunidade fitoplanctônica respondeu sazonalmente às estações do ano, predominando a classe Cyanophyceae na primavera e a classe Chlorophyceae nas demais estações e não houve melhoria na qualidade da água durante a série. / The three shallow cascading reservoir system are located in Parque Estadual das Fontes do Ipiranga (PEFI) Biological Reserve in the southern of São Paulo city where located headwater Ipiranga Stream. The first reservoir is linked to Lago das Garças, a shallow and eutrophic environment, where have become frequent blooms of Cyanobacteria that produce aggressive toxins which cause problems to environment and public health. Objective. This study aimed to analyze the sazonal variation of the phytoplankton community of three shallow cascading reservoir system subsequent of a eutrophic lake and avaliated the water quality. Material and Methods. Samples were collected quarterly during the period of one year (October/2005 to July/2006), in the deepest part of the each lake, in two depths. Morphometric variables (superficial area, perimeter, maximum length and depth), climatic variables (air temperature and precipitation), physical and chemical variables (water temperature, transparence of water, euphotic zone, pH, conductivity, turbidity, dissolved oxygen, biochemical oxygen demand, nutrients), biological variables (total and fecal coliforms, chlorophyll-a, pheopigments, species composition, density, biovolume, cells number and descriptions species) were determined. Qualitative samples were collected at the surface using planktonic net (20 µm) and identificated using a binocular optic microscope. Quantitative samples were obtained by collecting bottle and counting in inverted microscope. Multivariate statistical analysis was applied to calculate the correlations between biological and environmental data. Results. The phytoplankton community was composed of 125 taxons distributed in 12 classes: Chlorophyceae (38,8%) was the main class regarding species richness and density, followed by the Cyanobacteria (23,8%), Euglenophyceae (8,7%), Cryptophyceae (6,3%), Zygnemaphyceae (5,5%), Bacillariophyceae (4,7%) and 11,1% for others classes (Chrysophyceae, Coscinodiscophyceae, Dinophyceae, Xanthophyceae, Craspedomonadophyceae and Fragilariophyceae). Taxons that had appeared during all study are: Microcystis aeruginosa, Cylindrospermopsis raciborskii, Planktothrix agardhii (Cyanobacteria). Cylindrospermopsis raciborskii and Chroococcus minutus are descriptions species and they can be considered bioindicator of pollution because their density are elevated (79,4% of total density). Conclusions. The phytoplankton community as well as the environmental variables responded to the seasonality, predominance of Cyanophyceae in spring and Chlorophyceae in others stations. It didn’t have improvement in the quality of the water during the serie.
4

Estudo da comunidade fitoplanctônica como bioindicador de poluição em três reservatórios em série do Parque Estadual das Fontes do Ipiranga (PEFI), São Paulo, SP / Phytoplankton community’s study as bioindicator of pollution in three cascading reservoir system in Parque Estadual das Fontes do Ipiranga (PEFI), São Paulo, SP

Adriana Guidetti Dias Lopes 13 August 2007 (has links)
Os três reservatórios rasos e em série localizam-se no Parque Estadual das Fontes do Ipiranga (PEFI), região sudoeste do município de São Paulo, numa unidade de conservação que abriga as nascentes do histórico riacho do Ipiranga. O primeiro reservatório recebe água do Lago das Garças, um sistema artificial eutrófico, onde já foram detectadas florações de cianobactérias potencialmente tóxicas e com problemas ecológicos, sanitários e estéticos. Objetivo. Analisar a variação sazonal da comunidade fitoplanctônica de três reservatórios rasos subseqüentes a um lago hipereutrófico localizado no município de São Paulo/SP, visando avaliar a qualidade da água durante o sistema em série. Material e Métodos. As coletas foram realizadas trimensalmente durante o período de um ano (outubro/2005 a julho/2006), em uma estação de amostragem em cada um dos três reservatórios e a duas profundidades: superfície e fundo. Foram determinadas variáveis morfométricas (área superficial, perímetro, comprimento máximo e profundidade), climatológicas (temperatura do ar e precipitação), físicas e químicas (temperatura da água, transparência, zona eufótica, pH, condutividade, turbidez, oxigênio dissolvido, demanda bioquímica de oxigênio, fósforo total e ortofosfato, nitrogênio total e amoniacal), biológicas (coliformes totais e termotolerantes, clorofila-a, feofitina, composição florística, densidade total, biovolume, estimativa do número de células e espécies descritoras) e aplicações de índices biológicos. Na análise qualitativa foi empregada a rede de malha de 20 µm e identificação em microscópio óptico binocular com câmara clara. Na análise quantitativa, foi utilizado a garrafa coletora e método de sedimentação em câmara de volume definido e contagem em microscópio invertido. A ordenação dos dados foi realizada por meio da análise de componentes principais (ACP) e análise de correspondência canônica (ACC). Resultados. Como conseqüência da floração de cianobactérias registradas nos três reservatórios, foram identificados 125 táxons distribuídos em 12 classes. A classe com maior representatividade foi Chlorophyceae com 38,8%, seguida por Cyanobacteria (23,8%), Euglenophyceae (8,7%), Cryptophyceae (6,3%), Zygnemaphyceae (5,5%), Bacillariophyceae (4,7%) e 11,1% para as demais classes (Chrysophyceae, Coscinodiscophyceae, Dinophyceae, Xanthophyceae, Craspedomonadophyceae e Fragilariophyceae). Os táxons que apresentaram 100% de freqüência foram: Microcystis aeruginosa, Cylindrospermopsis raciborskii, Planktothrix agardhii (Cyanobacteria). As espécies descritoras que podem ser consideradas como bioindicadoras de poluição foram Cylindrospermopsis raciborskii e Chroococcus minutus, que juntas contribuíram com 79,4% de toda densidade deste estudo. Conclusões. A comunidade fitoplanctônica respondeu sazonalmente às estações do ano, predominando a classe Cyanophyceae na primavera e a classe Chlorophyceae nas demais estações e não houve melhoria na qualidade da água durante a série. / The three shallow cascading reservoir system are located in Parque Estadual das Fontes do Ipiranga (PEFI) Biological Reserve in the southern of São Paulo city where located headwater Ipiranga Stream. The first reservoir is linked to Lago das Garças, a shallow and eutrophic environment, where have become frequent blooms of Cyanobacteria that produce aggressive toxins which cause problems to environment and public health. Objective. This study aimed to analyze the sazonal variation of the phytoplankton community of three shallow cascading reservoir system subsequent of a eutrophic lake and avaliated the water quality. Material and Methods. Samples were collected quarterly during the period of one year (October/2005 to July/2006), in the deepest part of the each lake, in two depths. Morphometric variables (superficial area, perimeter, maximum length and depth), climatic variables (air temperature and precipitation), physical and chemical variables (water temperature, transparence of water, euphotic zone, pH, conductivity, turbidity, dissolved oxygen, biochemical oxygen demand, nutrients), biological variables (total and fecal coliforms, chlorophyll-a, pheopigments, species composition, density, biovolume, cells number and descriptions species) were determined. Qualitative samples were collected at the surface using planktonic net (20 µm) and identificated using a binocular optic microscope. Quantitative samples were obtained by collecting bottle and counting in inverted microscope. Multivariate statistical analysis was applied to calculate the correlations between biological and environmental data. Results. The phytoplankton community was composed of 125 taxons distributed in 12 classes: Chlorophyceae (38,8%) was the main class regarding species richness and density, followed by the Cyanobacteria (23,8%), Euglenophyceae (8,7%), Cryptophyceae (6,3%), Zygnemaphyceae (5,5%), Bacillariophyceae (4,7%) and 11,1% for others classes (Chrysophyceae, Coscinodiscophyceae, Dinophyceae, Xanthophyceae, Craspedomonadophyceae and Fragilariophyceae). Taxons that had appeared during all study are: Microcystis aeruginosa, Cylindrospermopsis raciborskii, Planktothrix agardhii (Cyanobacteria). Cylindrospermopsis raciborskii and Chroococcus minutus are descriptions species and they can be considered bioindicator of pollution because their density are elevated (79,4% of total density). Conclusions. The phytoplankton community as well as the environmental variables responded to the seasonality, predominance of Cyanophyceae in spring and Chlorophyceae in others stations. It didn’t have improvement in the quality of the water during the serie.
5

PRELIMINARY DISCUSSION ON GAS HYDRATE RESERVOIR SYSTEM OF SHENHU AREA, NORTH SLOPE OF SOUTH CHINA SEA

Wu, Nengyou, Yang, Shengxiong, Zhang, Haiqi, Liang, Jinqiang, Wang, Hongbin, Su, Xin, Fu, Shaoying 07 1900 (has links)
Gas hydrate is a very complicated reservoir system characterized of temperature, pressure, gas composition, pore-water geochemical features, and gas sources, gas hydrate distribution within the gas hydrate stability zone. Temperature, pressure and the gas composition of the sediments were suitable for gas hydrate formation in the gas hydrate reservoir system of Shenhu Area, north slope of South China Sea. The high-resolution seismic data and the gas hydrate drilling getting high concentrations of hydrate (>40%) in a disseminated form in foram-rich clay sediment showed that gas hydrate is distributed heterogeneously at all spatial scales in all drill holes, and the hydrate-bearing sediments ranged several ten meters in thickness are located in the lower part of gas hydrate stability zone (GHSZ), just above the bottom of gas hydrate stability zone (BGHSZ). It is likely seem that the methane to crystallize gas hydrate is from in-situ microbial methane.
6

Multireservoir Systems Optimization : A New Approach

Sharma, G K 12 1900 (has links) (PDF)
No description available.
7

Assessing the Tradeoffs of Water Allocation: Design and Application of an Integrated Water Resources Model

2015 November 1900 (has links)
The Bow River Basin in Southern Alberta is a semi-arid catchment, with surface water provided from the Rocky Mountains. Water resources in this basin, primarily surface water, are allocated to a variety of users- industry, municipalities, agriculture, energy and needs for the environment. The largest consumptive use is by agriculture (80%), and several large dams at the headwaters provide for over 800,000 MWhrs of hydropower. This water is managed by the 1990 Water Act, distributing water via licenses following the “first in time first in right” principle. Currently, the basin is over-allocated, and closed to any new licenses. Conflicts between different water users have consequences for the economy and the environment. By using an integrated water resources model, these conflicts can be further examined and solutions can be investigated and proposed. In this research an integrated water resources model, referred to as Sustainability-oriented Water Allocation Management and Planning Model applied to the Bow Basin (SWAMPB), is developed to emulate Alberta’s Water Resources Management Model (WRMM). While having the same allocation structure as WRMM, SWAMPB instead provides a simulation environment, linking allocation with dynamic irrigation and economic sub-models. SWAMPB is part of a much larger framework, SWAMP, to simulate the water resources systems for the entire South Saskatchewan River Basin (SSRB). SWAMPB integrates economics with a water resources allocation model as well as an irrigation model- all developed using the system dynamics approach. Water is allocated following the allocation structure provided in WRMM, through operation rules of reservoirs and diversions to water users. The irrigation component calculates the water balance of farms, determining the crop water demand and crop yields. An economic valuation is provided for both crops and hydropower generation through the economic component. The structure of SWAMPB is verified through several phases. First, the operation of reservoirs with fixed (known) inflows, and modeled releases, are compared against WRMM for a historical simulation period (1928-2001). Further verifications compare the operation of SWAMPB as a whole without any fixed flows but fixed demands to identify errors in the system water allocation. A final verification then compares both models against historical flows and reservoir levels to assess the validity of each model. SWAMPB, although found to have some minor differences in model structure due to the system dynamics modeling environment, is to be evaluated as an acceptable emulator. SWAMPB is applied to assess a variety of management and policy solutions to mitigating environmental flow deficit. Solutions include increasing irrigation efficiency (S1), requiring more summer release from hydropower reservoirs at the headwaters (S2), a combination of the previous two (S3), implementing the In-Stream Flow Needs (S4) and implementing Water Conservation Objectives (S5). The solutions are not only examined by their ability to restore river flows, but also with respect to the economic consequences and effect on hydropower, irrigation, and municipalities. It is found that the three technical solutions (S1, S2, and S3) provide economic gains and allow more efficient water use, but do little to restore streamflows. Conversely, the two policy solutions (S4 and S5) are more effective at restoring river flow, but have severe consequences on the economy and water availability for irrigation and municipal uses. This analysis does not recommend a particular solution, but provides a quantification of the tradeoffs that can be used by stakeholders to make decisions. Further work on the SWAMP methodology is foreseen, to link SWAMPB with other models, enabling a comprehensive analysis across the entire SSRB.
8

Estrutura populacional do Prochilodus brevis (SteindaChner,1875) (Characiformes, Prochilodontidae) em sistema de reservatórios de uma bacia hidrográfica do semiárido neotropical, Brasil / Fish; Curimatã; Species migratory; Spawning; Ecology

Moreira, Suzany Iasnaya Lopes 13 April 2015 (has links)
Made available in DSpace on 2016-08-31T13:19:26Z (GMT). No. of bitstreams: 1 SuzanyILM_DISSERT.pdf: 1345227 bytes, checksum: 8df554393ca0a302d49e17dbe4828ca0 (MD5) Previous issue date: 2015-04-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Prochilodus brevis (curimatã) is a migratory and endemic fish species of the hydrographic basin in semiarid region, occurring in rivers and reservoirs. The aims of this study was evaluate the population structure species in two reservoirs (Pau dos Ferros and Santa Cruz Reservoirs) that are located in the hydrographic basin of the Apodi/Mossoró River. The biological material was obtained through quarterly collections carried out from February/2011 to November/2012, using gillnets from 12 to 70mm. We evaluated Catch Per Unit Effort by the number (CPUEn), the length structure in 3 cm classes, sex ratio, the length-weight relationship (Wt), condition factor (K), the length at first maturity and the gonadosomatic index (GSI). The Pau dos Ferros Reservoir showed a higher abundance and better structured population with capture young individuals and adults in higher abundance. In the Pau dos Ferros Reservoir the distribution of the species was homogeneous, while in the Santa Cruz reservoir the species had a higher capture at at fluvial region. The sex ratio remained within the expected of 1:1 both the Pau dos Ferros reservoir as to the Santa Cruz reservoir. Isometric growth of the species (b=3.0109) was in Pau dos Ferros reservoir and allometric negative (b=2.6710) in the Santa Cruz Reservoir. Furthermore, the condition factor indicated that the population of the species in Pau dos Ferros reservoir had a better physiological condition. The length at first maturity for the Pau dos Ferros reservoir and Santa Cruz were 16.97cm and 17.40cm, respectively. Reproductive investment was similar between the reservoirs; however, for the population of the Santa Cruz reservoir is not being reflected in the recruitment of new individuals to the population, since that capture of juveniles was low. The results found suggested that the species maintain viable populations in Pau dos Ferros Reservoir, on the other hand in the Santa Cruz reservoir, probably in this reservoir species not found appropriate places to spawn and/or development of juveniles. Thus, the results suggested that the construction of the Santa Cruz reservoir was detrimental to the population of P. brevis and if appropriate measures are not taken handling species may disappear from the reservoir / O Prochilodus brevis (curimatã) é uma espécie migradora, endêmicas das bacias hidrográficas da região do semiárido, com ocorrência em rios e reservatórios da região. O presente trabalho teve como objetivo avaliar a estrutura populacional da espécie em dois reservatórios (Pau dos Ferros e Santa Cruz) localizados na bacia hidrográfica do rio Apodi/Mossoró. O material biológico foi obtido através de coletas trimestrais realizadas de fevereiro de 2011 a novembro de 2012, usando rede de espera. Foram analisados a Captura Por Unidade de Esforço (CPUE), a estrutura em comprimento em classes de 3 cm, a proporção sexual, a relação comprimento-peso (Wt), o fator de condição (K), o comprimento de primeira maturação e o índice gonadossomático (IGS). O reservatório de Pau dos Ferros apresentou uma maior abundância e uma população melhor estruturada com captura maior de indivíduos jovens e adultos. Diferente do reservatório de Pau dos Ferros em que a distribuição da espécie foi homogênea no reservatório de Santa Cruz a espécie teve uma maior captura nos pontos mais próximos ao rio. A proporção sexual permaneceu dentro do esperado DE 1:1 tanto para o reservatório de Pau dos Ferros como para o reservatório de Santa Cruz. A espécie apresentou crescimento isométrico (b=3,0109) no reservatório de Pau dos Ferros e alométrico negativo (b=2,6710) no reservatório de Santa Cruz. Além disso, o fator de condição indicou que a população da espécie no reservatório de Pau dos Ferros apresenta um estado fisiológico melhor. O comprimento de primeira maturação para o reservatório de Pau dos Ferros e Santa Cruz foi de 16,97cm e 17,40cm, respectivamente. O investimento reprodutivo foi semelhante entre os reservatórios, no entanto, para a população do reservatório de Santa Cruz não está se refletindo no recrutamento de novos indivíduos para a população, uma vez que, a captura de juvenis foi baixa nesse reservatório. Através desses resultados constatou-se que a espécie mantem populações viáveis no reservatório de Pau dos Ferros por outro lado no reservatório de Santa Cruz, provavelmente a espécie não encontrou locais apropriados para desovar e/ou desenvolvimento dos juvenis. Assim, os resultados sugerem que a construção do reservatório de Santa Cruz foi prejudicial para população de P. brevis e caso medidas adequadas de manejo não sejam tomadas a espécie poderá desaparecer do reservatório
9

Fuzzy State Reservoir Operation Models For Irrigation

Kumari, Sangeeta 18 July 2016 (has links) (PDF)
Efficient management of limited water resources in an irrigation reservoir system is necessary to increase crop productivity. To achieve this, a reservoir release policy should be integrated with an optimal crop water allocation. Variations in hydrologic variables such as reservoir inflow, soil moisture, reservoir storage, rainfall and evapotranspiration must be considered in the reservoir operating policy model. Uncertainties due to imprecision, subjectivity, vagueness and lack of adequate data can be handled using the fuzzy set theory. A fuzzy stochastic dynamic programming (FSDP) model with reservoir storage and soil moisture of the crops as fuzzy state variables and inflow as a stochastic variable, is developed to obtain a steady state reservoir operating policy. The model integrates the reservoir operating policy with the crop water allocation decisions by maintaining the storage continuity and the soil moisture balance. The reservoir release decisions are made in the model in 10-day periods and water is allocated to the crops on a daily basis. On comparison with the classical stochastic dynamic programming (SDP) model and a conceptual operation policy model, it is observed that the FSDP model, in general, results in lower release from the reservoir while maintaining lower soil moisture stress. However the steady state reservoir operation policy obtained using the FSDP model may not perform well in a short-term reservoir simulation. A fuzzy state short-term reservoir operation policy model with storage and soil moistures of the crops as fuzzy variables, is developed to obtain a real time release policy using forecasted inflow and forecasted rainfall. The distinguishing features of the model are accounting for (a) spatial variation of soil moisture and rainfall using gridded rainfall forecasts and (b) ponding depth requirement of the Paddy. On comparison with a conceptual operation policy model, the fuzzy state real time operation model is found most suitable for the application of the short term real time operation for irrigation. The real time operation model maintains high storage in the reservoir during most of the 10-day time periods of a year and results in a slightly lower annual releases as compared to the conceptual operation policy model. The effect of inflow forecast uncertainty is examined using different sets of forecasted inflows, and it is observed that the system performance is quite sensitive to inflow forecast uncertainties. The use of the satellite based gridded soil moisture in the real time operation model shows consideration of realistic situations. Further, three performance measures, viz., fuzzy reliability, fuzzy resiliency and fuzzy vulnerability are developed to evaluate the performance of the irrigation reservoir system under a specified operating policy. A fuzzy set with an appropriate membership function is defined to describe the working and failed states to account for the system being in partly working and partly failed state. The degree of failure of the irrigation reservoir system is defined based on the evapotranspiration deficit in a period. Inclusion of fuzziness in the performance measures enables realistic representation of uncertainties in the state of the system. A case study of Bhadra reservoir system in Karnataka, India is chosen for demonstrating the model applications.
10

Development of Space-Time Finite Element Method for Seismic Analysis of Hydraulic Structures / 農業水利施設の地震解析に向けたSpace-Time有限要素法の開発

Vikas, Sharma 25 September 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第21374号 / 農博第2298号 / 新制||農||1066(附属図書館) / 学位論文||H30||N5147(農学部図書室) / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 村上 章, 教授 藤原 正幸, 教授 渦岡 良介 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

Page generated in 0.0739 seconds