A New Methodology For Deriving Regional Time Of Concentration Equations Using GIS And Genetic Programming

Time of concentration (ToC) is the most frequently utilized time-scale parameter in hydrology which must be estimated accurately to ensure correct simulation of many different hydrological processes. Hydrologists have developed many empirical and semi-empirical methods for estimating ToC which are regional, watershed, and site-specific. Modellers are often confused by the number of ToC estimation methods and formulas and often select an equation without evaluating its correctness which leads to inaccurate simulation results. The importance of deriving and using regional ToC equations has been highlighted in many studies. In this paper, a methodology is proposed for deriving ToC equation(s) for watersheds located in a specific geographic region using GIS and Genetic Programming (GP). The use of GIS data allows for easy extraction of multiple characteristics of a large number of watersheds and sub-watersheds. Also, integration of GIS maps into the TR-55 model enables the determination of “true” TOC values for the watersheds under study. The obtained physical and hydrological characteristics of the watersheds are combined with rainfall characteristics and computed ToC values to form a large database. GP is then used as a data mining tool for conducting symbolic regression and deriving the most accurate set of equations for the watersheds of the region. In a case study, the proposed methodology is applied to 72 watersheds and sub-watersheds in Khorasan Razavi province, Iran. The method provides a set of different ToC equations to be used for watersheds with different sizes in the region. The equations proposed by GP are evaluated and compared to other conventional ToC estimation methods. The set of equations found by GP provides insight on the relationship between ToC and other watershed and rainfall characteristics and highlights the potential role of GP as an attractive and effective Knowledge Discovery tool

A Sustainable Water Resources Management Assessment Framework (SWRM-AF) for Arid and Semi-Arid Regions:Part 1: Developing the Conceptual Framework

The evaluation of water resources management practices is essential for water usage decisions in regions with limited water resources. The literature provides numerous assessment frameworks, but many ignore the unique characteristics and conditions of some special arid and semi-arid regions, such as the Gulf Cooperation Council (GCC) countries, which lack any permanent rivers or lakes. Thus, this study, the first in a two-part series, seeks to develop a conceptual Sustainable Water Resources Management Assessment Framework (SWRM-AF). General and particular criteria explain how components and indicators were identified. The conceptual SWRM-AF provided here has four components (environment, economy, society, and infrastructure) and 24 indicators. Almost every indicator has been selected from the literature and is briefly explained and justified. This research presents, possibly for the first time, clear and straightforward directions for evaluating each indicator in colour-coded tables. To create a more holistic framework for arid and semi-arid regions, social indicators like “intervention acceptability” and environmental indicators for assessing the impacts of desalination treatment plants have been added to form a unique framework applicable to such regions. Therefore, the components and indicators of conceptual SWRM-AF could work collectively to aid the process of decision-making. The next phase is validating this framework using a participatory approach

Modelling boundary shear stress distribution in open channels using a face recognition technique

This paper describes a novel application of a pattern recognition technique for predicting boundary shear stress distribution in open channels. In this approach, a synthetic database of images representing normalized shear stress distributions is formed from a training data set using recurrence plot (RP) analysis. The face recognition algorithm is then employed to synthesize the RPs and transform the original database into short-dimension vectors containing similarity weights proportional to the principal components of the distribution of images. These vectors capture the intrinsic properties of the boundary shear stress distribution of the cases in the training set, and are sensitive to variations of the corresponding hydraulic parameters. The process of transforming one-dimensional data series into vectors of weights is invertible, and therefore, shear stress distributions for unseen cases can be predicted. The developed method is applied to predict boundary shear stress distributions in smooth trapezoidal and circular channels and the results show a cross correlation coefficient above 92%, mean square errors within 0.04% and 4.48%, respectively, and average shear stress fluctuations within 2% and 5%, respectively, thus indicating that the proposed method is capable of providing accurate estimations of the boundary shear stress distribution in open channels.</jats:p

Coupling of Cellular Automata Urban Growth Model and HEC-HMS to Predict Future Flood Extents in the Upper Klang Ampang Catchment

Urban areas in tropical regions have higher flood risks due to the more frequent occurrence of intense convective rainfalls. The rising urbanization process have caused more surfaces to be covered with impervious materials, resulting in increased runoff. Modelling urban growth and its impact on urban hydrology is essential to ensure informed decision in the sustainable management and planning of cities in developing country like Malaysia. The aim of this research is to develop an integrated system for simulating future flood extents by coupling flood and urban growth models for the Upper Klang Ampang catchment which includes Kuala Lumpur capital city. HEC-HMS was used for flood modelling while SLEUTH cellular automata model was employed to analyse urban growth in the catchment. The results indicate that using historical satellite images from 1990, 2000, 2010 and 2016 as input data layers along with slope, land use, hill shade, road and restricted area layers, a slight increase in urban growth from 2020 until 2050 is predicted which can cause the peak discharge to increase by about 11-15%. The integrated flood estimation-urban growth system can be used as an effective tool in urban planning and management for the city

Coupling of Cellular Automata Urban Growth Model and HEC-HMS to Predict Future Flood Extents in the Upper Klang Ampang Catchment

Urban areas in tropical regions have higher flood risks due to the more frequent occurrence of intense convective rainfalls. The rising urbanization process have caused more surfaces to be covered with impervious materials, resulting in increased runoff. Modelling urban growth and its impact on urban hydrology is essential to ensure informed decision in the sustainable management and planning of cities in developing country like Malaysia. The aim of this research is to develop an integrated system for simulating future flood extents by coupling flood and urban growth models for the Upper Klang Ampang catchment which includes Kuala Lumpur capital city. HEC-HMS was used for flood modelling while SLEUTH cellular automata model was employed to analyse urban growth in the catchment. The results indicate that using historical satellite images from 1990, 2000, 2010 and 2016 as input data layers along with slope, land use, hill shade, road and restricted area layers, a slight increase in urban growth from 2020 until 2050 is predicted which can cause the peak discharge to increase by about 11-15%. The integrated flood estimation-urban growth system can be used as an effective tool in urban planning and management for the city

Strength assessment of Al-Humic and Al-Kaolin aggregates by intrusive and non-intrusive methods

Made available in DSpace on 2019-10-06T15:34:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-06-15Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Resistance to breakage is a critical property of aggregates generated in water and wastewater treatment processes. After flocculation, aggregates should ideally keep their physical characteristics (i.e. size and morphology), to result in the best performance possible by individual separation processes. The integrity of aggregates after flocculation depends upon their capacity to resist shear forces while transported through canals, passages, apertures, orifices and other hydraulic units. In this study, the strength of Al-Humic and Al-Kaolin aggregates was investigated using two macroscopic measurement techniques, based on both intrusive and non-intrusive methods, using image analysis and light scattering based equipment. Each technique generates different information which was used for obtaining three floc strength indicators, namely, strength factor (SF), local stress from the hydrodynamic disturbance (σ) and the force coefficient (γ) for two different study waters. The results showed an increasing trend for the SF of both Al-Humic and Al-Kaolin aggregates, ranging from 29.7% to 78.6% and from 33.3% to 85.2%, respectively, in response to the increase of applied shear forces during flocculation (from 20 to 120 s−1). This indicates that aggregates formed at higher shear rates are more resistant to breakage than those formed at lower rates. In these conditions, σ values were observed to range from 0.07 to 0.44 N/m2 and from 0.08 to 0.47 N/m2 for Al-Humic and Al-Kaolin, respectively. Additionally, it was found that for all studied conditions, the resistance of aggregates to shear forces was nearly the same for Al-Humic and Al-Kaolin aggregates, formed from destabilized particles using sweep coagulation. These results suggest that aggregate strength may be mainly controlled by the coagulant, emphasizing the importance of the coagulant selection in water treatment. In addition, the use of both intrusive and non-intrusive techniques helped to confirm and expand previous experiments recently reported in literature.Instituto de Geociências e Ciências Exatas Univ. Estadual Paulista (UNESP), Av. 24-A, 1515, Jardim Bela Vista, Rio ClaroPrograma de Pós-graduação em Engenharia Civil e Ambiental Univ. Estadual Paulista (UNESP), Av. 24-A, 1515, Jardim Bela Vista, Rio ClaroDepartment of Civil Engineering University of BirminghamDepartment of Civil Environmental and Geomatic Engineering University College London, Gower StInstituto de Geociências e Ciências Exatas Univ. Estadual Paulista (UNESP), Av. 24-A, 1515, Jardim Bela Vista, Rio ClaroPrograma de Pós-graduação em Engenharia Civil e Ambiental Univ. Estadual Paulista (UNESP), Av. 24-A, 1515, Jardim Bela Vista, Rio ClaroFAPESP: 2017/19195-

A grounded theory based framework for level of development implementation within the information delivery manual

The present study follows the progress of the level of development (LOD) specification from its inception in 2005 to its latest updates in 2018, a total of 42 guidelines from North America and Europe are reviewed. To organise the presented literature and to provide a comprehensive framework of LOD implementation within the information delivery manual (IDM), a LOD grounded theory-based taxonomy is introduced. The variables that constitute this taxonomy are BIM purpose, Stage, Role, Classification System, Attribute, Graphical information, Scale, LOD and Net benefits. The result of this exercise is a comprehensive view of the LOD construct impact on project performance which can be studied as a cumulative framework, where new research on the constructs can be added. Therefore, this allows a point towards the direction where further work is needed within the field of LOD-IDM implementation, such as the study of its use for data management among other uses