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    Tropical Algebraic Geometry

    , M.Sc. Thesis Sharif University of Technology Yaghmayi, Keyvan (Author) ; Rastegar, Arash (Supervisor)
    Abstract
    Tropical algebraic geometry is a fairly new branch in geometry which is called so in honor of Brazilian mathematician Imre Simon who was pioneer of this field.The set equipped with the addition and multiplication is a semifield.Algebraic geometry objects like algebraic varieties can be defined over.Polynomials and rational functions are defined over.The functions that they define are piecewise linear and concave functions and the set of points where they are nonlinear is a tropical variety which is a concave polyhedral. Thus, tropical algebraic geometry is a piecewise linear version of algebraic geometry.Another approach to tropical algebraic geometry comes back to the works of Russian... 

    A Tropical Approach to Arithmetic Geometry

    , M.Sc. Thesis Sharif University of Technology Hosseini Jafari, Farid (Author) ; Rastegar, Arash (Supervisor)
    Abstract
    In this thesis we introduce Tropical Geometry and It’s Application in Arithmetic Geometry  

    Article an estimation of the anthropogenic heat emissions in darwin city using urban microclimate simulations

    , Article Sustainability (Switzerland) ; Volume 14, Issue 9 , 2022 ; 20711050 (ISSN) Rajapaksha, S ; Nnachi, R. C ; Tariq, M. A. U. R ; Ng, A. W. M ; Abid, M. M ; Sidiqui, P ; Rais, M. F ; Aamir, E ; Diaz, L. H ; Kimiaei, S ; Mehdizadeh Rad, H ; Sharif University of Technology
    MDPI  2022
    Abstract
    The energy consumption due to urbanization and man-made activities has resulted in production of waste, heat, and pollution in the urban environment. These have further resulted in undesirable environmental issues such as the production of excessive Anthropogenic Heat Emissions (AHE), thus leading to an increased Urban Heat Island (UHI) effect. The aim of this study was to estimate the total AHE based on the contribution of three major sources of waste heat generation in urban environment, i.e., buildings, vehicular traffic, and human metabolism. Furthermore, a comparison of dominating anthropogenic heat factor of Darwin with that of other major international cities was carried out. Field... 

    Numerical Modeling of Waves Generated by Tropical Cyclone and its Effects on Oman Sea

    , M.Sc. Thesis Sharif University of Technology Taeb, Peyman (Author) ; Abbaspour Tehrani Fard, Majid (Supervisor)
    Abstract
    Sea and ocean waves develop in various ways especially by blowing wind over them. Modeling of these waves has been in center of interest for half a century. After the pioneering study of Gelchi et al (1995), ocean wave models are generally base on a spectral energy or action balance equation. Ocean storms such as tropical cyclone will develop if the atmospheric and oceanic conditions are available. Their Rotational and transition movement causes different patterns of waves. In 2007, cyclone Gonu, a tropical cyclone that formed in Indian ocean and have steered to Oman Sea and also caused damages and casualties in southern coast of Iran. Since intense tropical cyclones such as Gonu have... 

    A novel hybrid desiccant-based ejector cooling system for energy and carbon saving in hot and humid climates

    , Article International Journal of Refrigeration ; Volume 101 , Volume 101 , 2019 , Pages 196-210 ; 01407007 (ISSN) Heidari, A ; Rostamzadeh, H ; Avami, A ; Sharif University of Technology
    Elsevier Ltd  2019
    Abstract
    Desiccant-based evaporative cooling systems are considered as an energy efficient alternative to conventional vapor compression systems in humid climates. A novel hybrid desiccant-based ejector cooling (hybrid DEC) system is here presented to utilize low grade heat. In order to evaluate the system performance under subtropical humid climates, a dynamic hourly simulation of the system is performed for a typical building in Sydney. The results indicate that the hybrid DEC system is able to provide comfort conditions in subtropical and humid climates. Hybrid DEC system has a significant higher coefficient of performance compared to the conventional vapor compression system resulting to 84%... 

    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 Soltani, S. S ; 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... 

    Comparison and assessment of spatial downscaling methods for enhancing the accuracy of satellite-based precipitation over Lake Urmia Basin

    , Article Journal of Hydrology ; Volume 596 , 2021 ; 00221694 (ISSN) Karbalaye Ghorbanpour, A ; Hessels, T ; Moghim, S ; Afshar, A ; Sharif University of Technology
    Elsevier B.V  2021
    Abstract
    Estimating precipitation at high spatial-temporal resolution is vital in manifold hydrological, meteorological and water management applications, especially over areas with un-gauged networks and regions where water resources are on the wane. This study aims to evaluate five downscaling methods to determine the accuracy and efficiency of which on generating high-resolution precipitation data at annual and monthly scales. To establish precipitation-Land surface characteristics relationship, environmental factors, including Normalized Difference Vegetation Index (NDVI), Land Surface Temperature (LST) and Digital Elevation Model (DEM), were considered as proxies in the spatial downscaling... 

    An efficient biosurfactant-producing bacterium pseudomonas aeruginosa MR01, isolated from oil excavation areas in south of Iran

    , Article Colloids and Surfaces B: Biointerfaces ; Volume 69, Issue 2 , 2009 , Pages 183-193 ; 09277765 (ISSN) Bagheri Lotfabad, T ; Shourian, M ; Roostaazad, R ; Rouholamini Najafabadi, A ; Adelzadeh, M. R ; Akbari Noghabi, K ; Sharif University of Technology
    2009
    Abstract
    A bacterial strain was isolated and cultured from the oil excavation areas in tropical zone in southern Iran. It was affiliated with Pseudomonas. The biochemical characteristics and partial sequenced 16S rRNA gene of isolate, MR01, was identical to those of cultured representatives of the species Pseudomonas aeruginosa. This bacterium was able to produce a type of biosurfactant with excessive foam-forming properties. Compositional analysis revealed that the extracted biosurfactant was composed of high percentages lipid (∼65%, w/w) and carbohydrate (∼30%, w/w) in addition to a minor fraction of protein (∼4%, w/w). The best production of 2.1 g/l was obtained when the cells were grown on...