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Revisiting bathymetry dynamics in Lake Urmia using extensive field data and high-resolution satellite imagery
, Article Journal of Hydrology ; Volume 603 , 2021 ; 00221694 (ISSN) ; Bayati, M ; Tajrishy, M ; Chehrenegar, B ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Bathymetric mapping for an accurate estimation of stored water volume in drying lakes is a key information for an effective monitoring of their recession or restoration status. Extraction of bathymetry in shallow saline lakes using remote sensing techniques has always been challenging due to the complex influences imposed by the physical properties of substrate and the spatial variability of salinity. In this study, we developed a machine learning-based model to quantify the implicit, non-linear relationship between water depth and surface reflectance by leveraging extensive in-situ data and high-resolution satellite imagery. We trained and tested the learning model in the hyper-saline Lake...
Lake Urmia crisis and restoration plan: Planning without appropriate data and model is gambling
, Article Journal of Hydrology ; Volume 576 , 2019 , Pages 639-651 ; 00221694 (ISSN) ; Ataie Ashtiani, B ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Losing eight meters of water level over a 20-year period from 1996 to 2016 marked the Lake Urmia (LU) as one of the regional environmental crises. This condition has threatened biota life, intensified desertification around the lake, and raised social concerns by adversely impacting the inhabitants’ health and economy. In 2013, the Urmia Lake Restoration National Committee (ULRNC) started implementing certain management practices to stop the drying trend of LU, resulted in the cease of water level drop and stabilization of LU condition in 2016. Nevertheless, the restoration actions have not yet raised the lake to the water level as planned by the roadmap. This paper aims to describe and to...
Modeling of Water-energy Cycle and Water Particle Pathways in the Gadarchay Subbasin of the Lake Urmia Basin
, M.Sc. Thesis Sharif University of Technology ; Danesh Yazdi, Mohammad (Supervisor)
Abstract
The water level of Lake Urmia has experienced a drop of 7.83 meters, from 1995 to 2017. According to previous studies, the uncontrolled development of agriculture, high consumption cultivation pattern, overuse of water resources for agricultural use and high water loss due to low irrigation efficiency, are the most important factors in the drying of Lake Urmia. Since agricultural sector is the largest water consumer (approximately 90%), the Lake Urmia Restoration Program has decided to study and implement the 40% reduction of water consumption in agricultural sector plans.Due to the inherent complexity of the Urmia Lake basin, accurate and realistic evaluation of the effectiveness of the...
Estimating the Spatial and Temporal Changes in The Salinity of the Hyper-Saline Lake Urmia Using Sentinel-2 Imagery
, M.Sc. Thesis Sharif University of Technology ; Danesh-Yazdi, Mohammad (Supervisor)
Abstract
The spatiotemporal dynamic of salinity concentration (SC) in saline lakes is strongly dependent on the rate of water flow into the lake, water circulation, wind speed, evaporation rate, and the phenomenon of salt precipitation and dissolution. Although in-situ observations most reliably quantify water quality metrics, the spatiotemporal distribution of such data are typically limited and cannot be readily extrapolated for either long-term projections or extensive area. Alternatively, remotely sensed imagery has facilitated less expensive and a stronger ability to estimate water quality over a wide range of spatiotemporal resolutions. This study introduces an adaptive learning model that...
The Impact of Water Quality on the Accuracy of Water Depth Estimation Using Remote Sensing
, M.Sc. Thesis Sharif University of Technology ; Danesh Yazdi, Mohammad (Supervisor)
Abstract
Bathymetric maps are used for monitoring water bodies such as lakes, wetlands, and coastal areas, providing valuable information regarding changes in water storage volumes in these environments. For lakes prone to drying and salinity issues, where the lakebed elevation is constantly changing, the importance of these maps becomes even more pronounced as they play a crucial role in monitoring these lakes' conditions and assessing restoration efforts. Various methods exist for generating bathymetric maps, one of which is satellite remote sensing, which is more time- and cost-effective than traditional methods. One of the most common and accessible types of remote sensing data used for...
Conflict Resolution of Water Resources Allocations using the Game Theoretic Approach:The Case of Orumieh River Basin
, M.Sc. Thesis Sharif University of Technology ; Abrishamchi, Ahmad (Supervisor)
Abstract
The unavoidable consequences of increased demand for, and decreased supply of, various natural resources, especially water, have caused increased conflict over their allocation. Water allocations merely based on a water rights approach usually do not make efficient use of water for the whole river basin. Thus, there is a need for a comprehensive and stable allocation method that can satisfy all the involved interest groups. One of these methods is game theory that can be used to allocate water resources among riparian parties regarding principles of equity, efficiency and sustainability. In this study, a comprehensive linear programming model has been developed firstly to achieve the optimal...
The Impact of Dam Construction in Turkey on the Intensity and Frequency of Dust Events in Western Iran
, M.Sc. Thesis Sharif University of Technology ; Danesh Yazdi, Mohammad (Supervisor)
Abstract
This study analyzes the impact of climate-related stressors and water resources development projects in the Tigris-Euphrates Basin on regional dust storm intensity and frequency. To this end, we utilize remote sensing data for Aerosol Optical Depth (AOD), wind speed, surface temperature, soil moisture, precipitation intensity and inter-arrival time, Standardized Precipitation Evapotranspiration Index (SPEI), and vegetation cover to explore long-term trends. To identify dust hotspots, we introduce a normalized intensity-frequency index (NIFI). The NIFI combines the arithmetic mean of AOD values and the frequency of daily AOD measurements exceeding a predefined threshold, to identify potential...
Quantifying the Relative Share of Factors in Drying Gorgan Bay and Miankaleh Peninsula by Studying Long-Term Water Balance
, M.Sc. Thesis Sharif University of Technology ; Danesh Yazdi, Mohammad (Supervisor)
Abstract
GB and Miankale Wetland are one of the most valuable water areas in the country from an ecological perspective, providing a habitat for a wide range of aquatic species and birds as well as providing a platform for fishing and tourism for locals. Recently, this wildlife refuge has experienced a crisis of reduced water levels and degraded water quality. Past studies have examined how fluctuations in the Caspian Sea water level affect GB's water quantity and quality. Due to the critical situation of Gorgan Bay, other factors affecting its water balance and upstream basin need to be examined, such as ground water flow and consumption, precipitation, and evaporation, and how they all affect the...
Determining the Optimal Irrigation Pattern in Agricultural Areas Using a Combination of Remote Sensing Data and the Development of a Lump Soil Moisture Model
, M.Sc. Thesis Sharif University of Technology ; Danesh-Yazdi, Mohammad (Supervisor)
Abstract
The purpose of this study is to introduce a new indicator to estimate the amount of irrigation water in excess of the need and also to determine the optimal irrigation pattern to reduce water loss in agriculture. According to the Food and Agriculture Organization of the United Nations, the major loss of fresh water takes place in agriculture, and the reduction of water resources is more significant in developing countries that do not have advanced agricultural equipment. One of the challenges in the studies related to reducing the amount of water used in agriculture is a lack of knowledge on the spatial distribution and temporal changes in water loss in a region. Although estimation of...
Exploring the Efficiency of Machine Learning Algorithms in Estimating Time-Variant Travel Time Distributions in River Basins
, M.Sc. Thesis Sharif University of Technology ; Danesh Yazdi, Mohammad (Supervisor)
Abstract
This study aimed to investigate the efficiency of machine learning algorithms in capturing the dynamics of water particles' age distribution and in estimating the time series of median travel time (MTT) in river basins. The mechanism of solute transport in a catchment does not follow the hydrograph shape of the catchment and depends on the spatial and temporal distribution of solute resident time. The equations governing the age dynamics of water particles discharged from a catchment have been presented analytically in recent research. These equations showed that the transfer of solutes depends on various factors, including climatic conditions, basin topography, and basin vegetation. Also,...
Determination and Simulation of Socio-Economic Urban Water Conservation Behavior Using Structural Equation Modeling and Agent Based Modeling
, M.Sc. Thesis Sharif University of Technology ; Danesh Yazdi, Mohammad (Supervisor)
Abstract
Water shortage, population growth, and high levels of urban water demand are among main challenges of water demand management for developing countries and cities, and also for megacities. Urban water management systems, as they are complex adaptive systems, complex interactions exist among elements affecting the system. In other words, action from a subpart can trigger other parts, and also the whole system to respond in reaction. In this study, socio-economic water consumption behavior of households is studies and simulated in an agent-based modeling platform. First, households are interviewed and, using the qualitative data extracted from interviews and also the behavioral science...
Exploring the Impact of Vegetation Type and Plant Growth Cycle on the Evapotranspiration Storage Selection Function Using Particle Tracking Approach
, M.Sc. Thesis Sharif University of Technology ; Danesh Yazdi, Mohammad (Supervisor)
Abstract
StorAge selection (SAS) functions describe the mechanism by which water particles with different ages exit a hydrological system through outfluxes such as streamflow and evapotranspiration (ET). The shape of the ET SAS functions affects the storage residence time distributions, ET travel time distributions, and discharge travel time distributions that control the hydrochemical dynamics of water. They also carry fundamental information to understand the response behavior of the system, and are affected by processes such as precipitation, outflow, ET, as well as the physical properties of the system. To better understand the shape of these functions, other important factors such as the type...
Exploring source water mixing and transient residence time distributions of outflow and evapotranspiration with an integrated hydrologic model and Lagrangian particle tracking approach
, Article Ecohydrology ; 2018 ; 19360584 (ISSN) ; Condon, L. E ; Danesh Yazdi, M ; Bearup, L. A ; Sharif University of Technology
John Wiley and Sons Ltd
2018
Abstract
Understanding the time water takes as it moves from rain or snowmelt through the terrestrial system to arrive as stream discharge, or evapotranspiration (ET) is an important hydrologic quantity. We develop a Lagrangian particle tracking method to capture transient residence times from source to either ET or outflow in an integrated hydrologic model. This method is parallel and efficiently captures time evolution of parcels of water in the model and tracks the source of water for hydrograph or ET separation. We demonstrate this model using hypothetical hillslope simulations driven by snow or rain dominated forcing and two different land cover types. We show that land cover and forcing both...
A probabilistic framework for water budget estimation in low runoff regions: A case study of the central Basin of Iran
, Article Journal of Hydrology ; Volume 586 , 2020 ; Ataie Ashtiani, B ; Danesh Yazdi, M ; Simmons, C. T ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Utilizing ground-based measurements to obtain water budget components, especially in large scale basins, is challenging due to the limitation in the spatiotemporal availability of in-situ data. In this paper, we propose a probabilistic framework for estimating water budgets in low runoff regions using remote sensing products. By studying water budgets in the Central Basin of Iran (CBI) over 8 years period (2009–2016), we investigate the locations and time scales at which the water budget calculated from satellite products provides most closure. To this end, we use precipitation from the Tropical Rainfall Measuring Mission (TRMM), evapotranspiration from the Water Productivity Open Access...
Quantitative and Qualitative Assessment of Wetlands in Iran by Remote Sensing
, M.Sc. Thesis Sharif University of Technology ; Danesh Yazdi, Mohammad (Supervisor)
Abstract
Many of Iran's wetlands are going dry because of the expansion of anthropogenic activities like the exorbitant withdrawal of groundwater resources and excessive use of water for agricultural purposes. Bakhtegan, Hoor-ol-azim, Anzali, and Miankaleh are some of the most notable examples of this issue in the past two decades. The crucial role of wetlands in preserving the biodiversity of flora and fauna and supplying groundwater resources necessitates continuous monitoring of the quantitative and qualitative changes in the surface water of wetlands. The main focus of this research is quantifying the reduction in wetlands' surface water using K-means and random forest algorithms based on...
Phosphorus transport in intensively managed watersheds
, Article Water Resources Research ; Volume 55, Issue 11 , 2019 , Pages 9148-9172 ; 00431397 (ISSN) ; Boardman, E ; Danesh Yazdi, M ; Finlay, J. C ; Hansen, A. T ; Baker, A. C ; Dalzell, B ; Sharif University of Technology]
Blackwell Publishing Ltd
2019
Abstract
Understanding controls of P movement through watersheds are essential for improved landscape management in intensively managed regions. Here, we analyze observational data from 104 gaged river sites and 176 nongaged river sites within agriculturally dominated watersheds of Minnesota, USA, to understand the role of landscape features, land use practices, climate variability, and biogeochemical processes in total, dissolved and particulate P dynamics at daily to annual scales. Our analyses demonstrate that factors mediating P concentration-discharge relationships varied greatly across watersheds and included near-channel sediment sources, lake and wetland interception, assimilation by algal P,...
Analysis of micro-rotating disks based on the strain gradient elasticity
, Article Acta Mechanica ; Vol. 225, issue. 7 , 2014 , pp. 1955-1965 ; ISSN: 00015970 ; Asghari, M ; Sharif University of Technology
2014
Abstract
In this paper, the mechanical behavior of micro-rotating disks is investigated utilizing the strain gradient theory. The governing equation and boundary conditions are derived utilizing the variational method. The analytical solution for the derived equation is also presented. As a case study, some numerical results are presented to emphasize the importance of utilization of non-classical theories such as the strain gradient elasticity instead of the classical continuum theory in dealing with micro-rotating disks
Modeling real-time coordination systems using timed Bchi automata
, Article 2011 CSI International Symposium on Computer Science and Software Engineering, CSSE 2011, 15 June 2011 through 16 June 2011 ; June , 2011 , Pages 17-24 ; 9781612842073 (ISBN) ; Izadi, M ; Sharif University of Technology
2011
Abstract
Reo is an exogenous coordination language for synthesizing components participating in a component-based system. The notion of Bchi automaton over streams of records (BAR for short) is a proposed operational semantics for Reo that covers several aspects of coordination strategies such as synchronization, context dependencies and fairness constraints. In this paper and for the purpose of modeling real-time coordination systems specified by Reo, we present a timed version of BARs as the acceptors of timed streams of records. We show that timed BAR and its streams of records based semantics are more standard and also more expressive than timed constraint automaton which is the first proposed...
Analytical study of micro-rotating disks with angular acceleration on the basis of the strain gradient elasticity
, Article Acta Mechanica ; Volume 230, Issue 9 , 2019 , Pages 3259-3278 ; 00015970 (ISSN) ; Asghari, M ; Danesh, V ; Sharif University of Technology
Springer-Verlag Wien
2019
Abstract
The small-scale effects on the mechanical responses of micro-rotating disks with angular acceleration are investigated based on the strain gradient theory, as one of the powerful non-classical continuum theories which have been developed to justify the empirical observations of mechanical behavior in small-scale structures and components. The differential equations governing motion of the micro-disk elements in radial and circumferential direction together with the corresponding boundary conditions are derived. Then, an analytical solution is presented for the components of the displacement field which can be used as a base for determination of the components of the stress field. In a...
Elastoplastic stress study in thick-walled spherical vessels considering finite deformation
, Article 8th Biennial ASME Conference on Engineering Systems Design and Analysis, ESDA2006, Torino, 4 July 2006 through 7 July 2006 ; Volume 2006 , 2006 ; 0791837793 (ISBN); 9780791837795 (ISBN) ; Shamsaei, N ; Naghdabadi, R ; Danesh Sararoudi, M ; Sharif University of Technology
2006
Abstract
An exact elasto-plastic analytical solution for large-strained internal pressurized thick-walled spherical vessels made of elastic-linear and nonlinear hardening material is derived in this paper. This solution is based on the notion of finite strains, the deformation theory of Hencky and the yield criteria of von Mises and Tresca. Nolinear elastic solution of an axisymetric boundary value problem is used as a basis to generate its inelastic solution, whereas the Hyper-elastic constitutive equation is invoked to represent the material response in the elastic region. This method treats the material parameters as field variables. Their distributions are obtained in an iterative manner using...