References of "Mustafa, Ahmed Mohamed El Saeid"
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See detailProcedural generation of flood-sensitive urban layouts
Mustafa, Ahmed Mohamed El Saeid ULiege; Zhang, Xiao Wei; Aliaga et al

in Environment and Planning B: Urban Analytics and City Science (in press)

Aside from modeling geometric shape, three-dimensional (3D) urban procedural modeling has shown its value in understanding, predicting and/or controlling effects of shape on design and urban planning. In ... [more ▼]

Aside from modeling geometric shape, three-dimensional (3D) urban procedural modeling has shown its value in understanding, predicting and/or controlling effects of shape on design and urban planning. In this paper, instead of the construction of flood resistant measures, we create a procedural generation system for designing urban layouts that passively reduce water depth during a flooding scenario. Our tool enables exploring designs that passively lower flood depth everywhere or mostly in chosen key areas. Our approach tightly integrates a hydraulic model and a parameterized urban generation system with an optimization engine so as to find the least cost modification to an initial urban layout design. Further, due to the computational cost of a fluid simulation, we train neural networks to assist with accelerating the design process. We have applied our system to several real-world locations and have obtained improved 3D urban models in just a few seconds. [less ▲]

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See detailAssessment of thermal overheating in free-running buildings in Cairo
Attia, Shady ULiege; Mustafa, Ahmed Mohamed El Saeid ULiege; Singh, Manoj Kumar

in Finlayson, Will; Roaf, Susan (Eds.) PROCEEDINGS OF THE 1ST INTERNATIONAL CONFERENCE ON COMFORT AT THE EXTREMES: ENERGY, ECONOMY AND CLIMATE (2019, April 10)

Assessing human health under climate change in hot climates is of particular importance in the Middle East. Cairo is one of those cities that have an estimated 2018 population as high as 13 million, with ... [more ▼]

Assessing human health under climate change in hot climates is of particular importance in the Middle East. Cairo is one of those cities that have an estimated 2018 population as high as 13 million, with a metropolitan population of 21 million, which makes it the largest city in Africa and the Middle East. In and around Cairo, many of the summer seasonal deaths are blamed on human discomfort due to anthropogenic climate change. High urban population density, urban heat island effect, cramped living conditions including housing, schools and prisons are all reasons to the increase of heat-related health problems in Cairo. Therefore, this initial study investigates and maps overheating in free-running residential buildings in Cairo. The study follows a combined, monitoring and observational assessment of the 2015 heat wave (19-day event) in Egypt. Using surface urban heat island maps, representative urban areas were determined and field measurements were carried out to assess indoor air temperatures and relative humidity. This was followed by observational field visits and interaction with local citizens to document the impacts and adaptation measures corresponding to overheating. The paper provides insights on indoor human discomfort with a focus on physical and non-physical heat stress reasons during climate extremes. The study provides initial insights on thermal comfort that can prompt local professionals and governments to address overheating and thermal stress in free-running residential buildings. [less ▲]

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See detailInvestigating the Impact of Urban Layout Geometry on Urban Flooding
Mustafa, Ahmed Mohamed El Saeid ULiege; Zhang, Xiao Wei; Aliaga, Daniel G. et al

in Proceedings of GEOProcessing 2019 (2019)

In this paper, we use a procedural generation system to design urban layouts that passively reduce water depth during urban floods. The tool enables designing cities that passively lower flood depth ... [more ▼]

In this paper, we use a procedural generation system to design urban layouts that passively reduce water depth during urban floods. The tool enables designing cities that passively lower flood depth everywhere or in chosen key areas. Our approach integrates a porosity-based hydraulic model and a parameterized urban generation system with an optimization engine so as to find the least cost modification to an initial urban layout. In order to investigate the relationship between urban layout design parameters and flood inundation depth, correlation coefficient method is used. This paper concludes that the most influential urban layout parameters are average road length and the mean parcel area. Keywords-inverse procedural modeling; urban layout design; porosity-based hydraulic model; Pearson correlation; urban flooding. [less ▲]

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See detailAutomatic design of flood-resilient urban layouts
Dewals, Benjamin ULiege; Mustafa, Ahmed Mohamed El Saeid ULiege; Bruwier, Martin ULiege et al

in Geophysical Research Abstracts (2019)

Urban planning is central to flood risk prevention. Flood-sensitive urban planning pursues two goals: reducing flood exposure and vulnerability [1]; but also addressing the influence of urban ... [more ▼]

Urban planning is central to flood risk prevention. Flood-sensitive urban planning pursues two goals: reducing flood exposure and vulnerability [1]; but also addressing the influence of urban characteristics on flood flow severity (flow depths and velocities) [2]. Focusing on the latter, we present here a unique software which automatically optimizes the geometry of urban layouts to enhance flood resilience [3]. The optimized parameters describe the arrangement of the road network, the blocks, the parcels, and the buildings. The proposed approach is particularly innovative since, so far, such automatic urban design tools were developed only for totally different objectives (e.g. optimizing sun exposure or distance to parks); but not in the context of flood risk management. Our automatic urban design system consists of three components: (i) a procedural urban model, (ii) a surrogate for a hydraulic model and (iii) an optimization engine. • Starting from a set of input parameters pi (typical road length, width, curvature …) the procedural urban model generates urban layouts which mimic fairly realistically real-world urban patterns [3]. • To achieve interactive feedback (i.e. getting the results within a few seconds), the system uses a neural network (NN) to approximate the relationship between urban layout and flood flow characteristics. The NN was trained using a relatively fast 2D porosity-based hydraulic model [4], which in turn was calibrated against a detailed shallow-water model [2]. • A Markov Chain Monte Carlo optimization is used to adjust iteratively the procedural model parameters pi so as to yield the desired urban layout. The system was tested for optimizing the layout of an urban district of 1 km by 1 km subject to river flooding. The system runs about one minute to find the optimal urban layout. The system tends to improve the flow conveyance through the urban area by increasing the voids in-between the buildings (e.g., increase road width) and by promoting a more “fragmented” urban pattern (e.g., decrease road length). The optimization reduces the flood water depths in the district by up to 20 to 25%. Several real-world examples showcase the operationality of the system for improving flood resilience through flood-sensitive urban design [3]. In practice, such an interactive digital tool can valuably assist urban planners and architects to assess the implications of various design decisions on flooding and end up with improved flood-sensitive urban layouts. The approach should be further developed to accommodate more diverse flooding scenarios (e.g. pluvial floods, coastal floods, etc.). References [1] Mustafa, A. et al. (2018). Effects of spatial planning on future flood risks in urban environments. J. Environ. Manage. 225, 193–204. [2] Bruwier, M. et al. (2018). Influence of urban pattern on inundation flow in floodplains of lowland rivers. Sci. Total Environ. 622-623, 446–458. [3] Mustafa, A. et al. (2019). Procedural Generation of Flood-Sensitive Urban Layouts. Environ Plan B Urban Anal City Sci. In press. [4] Bruwier, M. et al. (2017). Shallow-water models with anisotropic porosity and merging for flood modelling on Cartesian grids. J. Hydrol. 554, C, 693–709. [less ▲]

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See detailAn efficient hierarchical model for multi-source information fusion
Saadi, Ismaïl ULiege; Farooq, Bilal; Mustafa, Ahmed Mohamed El Saeid ULiege et al

in Expert Systems with Applications (2018), 110

In urban and transportation research, important information is often scattered over a wide variety of independent datasets which vary in terms of described variables and sampling rates. As activity-travel ... [more ▼]

In urban and transportation research, important information is often scattered over a wide variety of independent datasets which vary in terms of described variables and sampling rates. As activity-travel behavior of people depends particularly on socio-demographics and transport/urban-related variables, there is an increasing need for advanced methods to merge information provided by multiple urban/transport household surveys. In this paper, we propose a hierarchical algorithm based on a Hidden Markov Model (HMM) and an Iterative Proportional Fitting (IPF) procedure to obtain quasi-perfect marginal distributions and accurate multi-variate joint distributions. The model allows for the combination of an unlimited number of datasets. The model is validated on the basis of a synthetic dataset with 1,000,000 observations and 8 categorical variables. The results reveal that the hierarchical model is particularly robust as the deviation between the simulated and observed multivariate joint distributions is extremely small and constant, regardless of the sampling rates and the composition of the datasets in terms of variables included in those datasets. Besides, the presented methodological framework allows for an intelligent merging of multiple data sources. Furthermore, heterogeneity is smoothly incorporated into micro-samples with small sampling rates subjected to potential sampling bias. These aspects are handled simultaneously to build a generalized probabilistic structure from which new observations can be inferred. A major impact in term of expert systems is that the outputs of the hierarchical model (HM) model serve as a basis for a qualitative and quantitative analyses of integrated datasets. [less ▲]

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See detailEffects of spatial planning on future flood risks in urban environments
Mustafa, Ahmed Mohamed El Saeid ULiege; Bruwier, Martin ULiege; Archambeau, Pierre ULiege et al

in Journal of Environmental Management (2018), 225

Urban development may increase the risk of future floods because of local changes in hydrological conditions and an increase in flood exposure that arises from an increasing population and expanding ... [more ▼]

Urban development may increase the risk of future floods because of local changes in hydrological conditions and an increase in flood exposure that arises from an increasing population and expanding infrastructure within flood-prone zones. Existing urban land use change models generally consider the expansion process and do not consider the densification of existing urban areas. In this paper, we simulate 24 possible urbanization scenarios in Wallonia region (Belgium) until 2100. These scenarios are generated using an agent-based model that considers urban expansion and densification as well as development restrictions in flood-prone zones. The extents of inundation and water depths for each scenario are determined by the WOLF 2D hydraulic model for steady floods corresponding to return periods of 25, 50, and 100 years. Our results show that future flood damages and their spatial distributions vary remarkably from one urbanization scenario to another. A spatial planning policy oriented towards strict development control in flood-prone zones leads to a substantial mitigation of the increased flood damage. By contrast, a spatial planning policy exclusively oriented to infill development with no development restrictions in flood-prone zones would be the most detrimental in terms of exposure to flood risk. Our study enables the identification of the most sensitive locations for flood damage related to urban development, which can help in the design of more resilient spatial planning strategies and localize zones with high levels of flood risk for each scenario. [less ▲]

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See detailComparison among three automated calibration methods for cellular automata land use change model: GA, PSO and MCMC
Mustafa, Ahmed Mohamed El Saeid ULiege; Saadi, Ismaïl ULiege; Ebaid, Amr et al

in Proceedings of AGILE conference 2018 (2018, June)

Spatial cellular automata (CA) model is one of the most common approaches to simulate land use change. Generally, CA estimates the transition likelihood from one land use state to another according to ... [more ▼]

Spatial cellular automata (CA) model is one of the most common approaches to simulate land use change. Generally, CA estimates the transition likelihood from one land use state to another according to local neighbourhood dynamics and global drivers. Logistic regression (logit) method is widely used to calibrate CA models. Recently, several optimization algorithms have been introduced to calibrate CA models. This study compares the performance of three optimization algorithms: (i) genetic algorithm (GA), (ii) particle swarm optimization (PSO), (iii) and Markov Chain Monte Carlo (MCMC). The three algorithms are incorporated into a CA model to simulate urban expansion in Wallonia (Belgium). In addition, we compare the three calibration algorithms with the logit method. The results show that all three algorithms outperformed the logit method. The results also reveal that the performance of GA is slightly better than PSO and MCMC. [less ▲]

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See detailInfluence of urban pattern on inundation flow in floodplains of lowland rivers
Bruwier, Martin ULiege; Mustafa, Ahmed Mohamed El Saeid ULiege; Aliaga, Daniel G. et al

in Science of the Total Environment (2018), 622–623

The objective of this paper is to investigate the respective influence of various urban pattern characteristics on inundation flow. A set of 2,000 synthetic urban patterns were generated using an urban ... [more ▼]

The objective of this paper is to investigate the respective influence of various urban pattern characteristics on inundation flow. A set of 2,000 synthetic urban patterns were generated using an urban procedural model providing locations and shapes of streets and buildings over a square domain of 1 x 1 km². Steady two-dimensional hydraulic computations were performed over the 2,000 urban patterns with identical hydraulic boundary conditions. To run such a large amount of simulations, the computational efficiency of the hydraulic model was improved by using an anisotropic porosity model. This model computes on relatively coarse computational cells, but preserves information from the detailed topographic data through porosity parameters. Relationships between urban characteristics and the computed inundation water depths have been based on multiple linear regressions. Finally, a simple mechanistic model based on two district-scale porosity parameters, combining several urban characteristics, is shown to capture satisfactorily the influence of urban characteristics on inundation water depths. The findings of this study give guidelines for more flood-resilient urban planning. [less ▲]

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See detailDoes urban flood resilience compete with sustainable urban planning as a whole?
Bruwier, Martin ULiege; Mustafa, Ahmed Mohamed El Saeid ULiege; Archambeau, Pierre ULiege et al

in Geophysical Research Abstracts (2018, April), 20

Sustainable urban planning aims at designing the urban fabric so that it meets the needs of an expanding urban population, while synergistically addressing a number of environmental objectives such as ... [more ▼]

Sustainable urban planning aims at designing the urban fabric so that it meets the needs of an expanding urban population, while synergistically addressing a number of environmental objectives such as transport, energy and resource efficiency. Urban densification is a key concept in sustainable urban planning, as it contributes to reduce pressure on environmentally sensitive lands and it makes several services more efficient, including water and energy supply. Similarly, at a local level, intervening spaces in-between buildings should be minimized to enhance heating efficiency. In this communication, we will report on two recent studies focusing on urban flood resilience. Both of them suggest that flood-resilient urban design tends to conflict with the two aforementioned aspects of sustainable urban development. The first study was conducted at the regional level, covering the whole Walloon Region in Belgium (17,000 km2). First, an original agent-based model was used to generate multiple urbanization scenarios with contrasting assumptions on spatial planning policies: urban expansion (sprawl) vs. urban densification, various degrees of ban on new developments in flood-prone areas . . . Next, flood damage modelling was performed along over 1,300 km of river. The results show that the urban densification scenarios lead to systematically higher flood risk estimates, since they promote new developments in the vicinity of existing urban areas mainly located in the lower parts of the river valleys. In a second study, conducted at the district level, we investigated how inundation severity is affected by the arrangement of buildings in floodplains . A set of 2,000 building layouts were synthetized using procedural modelling (Bruwier et al., 2018). Each building layout is characterized by a set of parameters such as the typical street widths, building size . . . Next, the flow characteristics (water depth, flow velocity) were computed for each building layout considering the same flooding scenario. An original porosity-based model was set up for this purpose (Bruwier et al., 2017). The findings of the study reveal that increasing the separation space in-between buildings tends to improve flood-resilience at the district level, thanks to an increased flow conveyance across the urban area. At first sight, the conclusions inferred from the two studies focusing on flood-resilience only (higher future flood risk due to urban densification, benefit of keeping intervening space in-between buildings) seem to diverge from general good-practice in sustainable urban planning. We intend to use this provocative statement to foster discussion with the audience on issues such as: “How can more integrated approaches mitigate such apparent contradictions?”, “How to best modulate sustainable urban planning principles to accommodate urban flood resilience?” [less ▲]

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See detailComparing support vector machines with logistic regression for calibrating cellular automata land use change models
Mustafa, Ahmed Mohamed El Saeid ULiege; Rienow, Andreas; Saadi, Ismaïl ULiege et al

in European Journal of Remote Sensing (2018), 51(1), 391-401

Land use change models enable the exploration of the drivers and consequences of land use dynamics. A broad array of modeling approaches are available and each type has certain advantages and ... [more ▼]

Land use change models enable the exploration of the drivers and consequences of land use dynamics. A broad array of modeling approaches are available and each type has certain advantages and disadvantages depending on the objective of the research. This paper presents an approach combining cellular automata (CA) model and supported vector machines (SVMs) for modeling urban land use change in Wallonia (Belgium) between 2000 and 2010. The main objective of this study is to compare the accuracy of allocating new land use transitions based on CA-SVMs approach with conventional coupled logistic regression method (logit) and CA (CA-logit). Both approaches are used to calibrate the CA transition rules. Various geophysical and proximity factors are considered as urban expansion driving forces. Relative operating characteristic and a fuzzy map comparison are employed to evaluate the performance of the model. The evaluation processes highlight that the allocation ability of CA-SVMs slightly outperforms CA-logit approach. The paper also reveals that the major urban expansion determinant is urban road infrastructure. [less ▲]

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See detailSpatiotemporal modeling of interactions between urbanization and flood risk: a multi-level approach
Mustafa, Ahmed Mohamed El Saeid ULiege

Doctoral thesis (2018)

The main goal of this PhD research is to investigate the expected flood damage for future urban patterns at different scales. Four main steps are followed to accomplish this goal. In the first step, a ... [more ▼]

The main goal of this PhD research is to investigate the expected flood damage for future urban patterns at different scales. Four main steps are followed to accomplish this goal. In the first step, a retrospective analysis is performed for the evolution of the urban development in Wallonia (Belgium) as a case study. Afterward, two land use change models, cellular automata-based, and agent-based are proposed and compared. Based on this comparison, the agent-based model is employed to simulate future urbanization scenarios. An important feature of this research is evident in the consideration of the multiple densities of built-up areas, which enables to study both expansion and densification processes. As the model simulates urbanization up to 2100, forecasting land use change over such time frames entails very significant uncertainties. In this regard, uncertainty in land use change models has been considered. In the third step, 24 urbanization scenarios that differed in terms of spatial policies and urbanization rate are generated. The simulated scenarios have then been integrated with a hydrological model. The results suggest that urban development will continue within flood-prone zones in a number of scenarios. Therefore, in the fourth and last step, a procedural urban generation system is developed to analyze the respective influence of various urban layout characteristics on inundation flow, which assists in designing flood-resistant urban layouts within the flood-prone zones. [less ▲]

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See detailA Time Monte Carlo method for addressing uncertainty in land-use change models
Mustafa, Ahmed Mohamed El Saeid ULiege; Saadi, Ismaïl ULiege; Cools, Mario ULiege et al

in International Journal of Geographical Information Science (2018), 32(11), 2317-2333

One of the main objectives of land-use change models is to explore future land-use patterns. Therefore, the issue of addressing uncertainty in land-use forecasting has received an increasing attention in ... [more ▼]

One of the main objectives of land-use change models is to explore future land-use patterns. Therefore, the issue of addressing uncertainty in land-use forecasting has received an increasing attention in recent years. Many current models consider uncertainty by including a randomness component in their structure. In this paper, we present a novel approach for tuning uncertainty over time, which we refer to as the Time Monte Carlo (TMC) method. The TMC uses a specific range of randomness to allocate new land uses. This range is associated with the transition probabilities from one land use to another. The range of randomness is increased over time so that the degree of uncertainty increases over time. We compare the TMC to the randomness components used in previous models, through a coupled logistic regression-cellular automata model applied for Wallonia (Belgium) as a case study. Our analysis reveals that the TMC produces results comparable with existing methods over the short-term validation period (2000–2010). Furthermore, the TMC can tune uncertainty on longer-term time horizons, which is an essential feature of our method to account for greater uncertainty in the distant future. [less ▲]

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See detailAddressing the determinants of built-up expansion and densification processes at the regional scale
Mustafa, Ahmed Mohamed El Saeid ULiege; Van Rompaey, Anton; Cools, Mario ULiege et al

in Urban Studies (2018), 55(15), 32793298

An in-depth understanding of the main factors behind built-up development is a key prerequisite for designing policies dedicated to a more efficient land use. Infill development policies are essential to ... [more ▼]

An in-depth understanding of the main factors behind built-up development is a key prerequisite for designing policies dedicated to a more efficient land use. Infill development policies are essential to curb sprawl and allow a progressive recycling of low-density areas inherited from the past. This paper examines the controlling factors of built-up expansion and densification processes in Wallonia (Belgium). Unlike the usual urban/built-up expansion studies, our approach considers various levels of built-up densities to distinguish between different types of developments, ranging from low-density extensions (or sprawl) to high-density infill development. Belgian cadastral data for 1990, 2000, and 2010 were used to generate four classes of built-up areas, namely, non-, low-, medium- and high-density areas. A number of socioeconomic, geographic, and political factors related to built-up development were operationalized following the literature. We then used a multinomial logistic regression model to analyze the effects of these factors on the transitions between different densities in the two decades between 1990 and 2010. The findings indicate that all the controlling factors show distinctive variations based on density. More specifically, the centrality of zoning policies in explaining expansion processes is highlighted. This is especially the case for high-density expansions. In contrast, physical and neighborhood factors play a larger role in infill development, especially for dense infill development. [less ▲]

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See detailBenefits of a multiple‐solution approach in land change models
Mustafa, Ahmed Mohamed El Saeid ULiege; Ebaid, Amr; Teller, Jacques ULiege

in Transactions in GIS (2018)

Land change (LC) models are dedicated to a better understanding of land use and land cover dynamics. A fundamental aspect of those models lies in the calibration of spatial parameters underlying such ... [more ▼]

Land change (LC) models are dedicated to a better understanding of land use and land cover dynamics. A fundamental aspect of those models lies in the calibration of spatial parameters underlying such dynamics. Although there are many studies on the calibration of LC models, current efforts have a common goal of seeking to find a single global optimum solution, even though land change dynamics may be inherently heterogeneous throughout a given space. This article presents a calibration approach for finding multiple optimal solutions. A crowding niching genetic algorithm (CNGA) is incorporated into a cellular automata LC model. The model is applied to simulate urban expansion in Wallonia (Belgium) as a case study. Our findings demonstrate the ability of the model to locate multiple solutions simultaneously. In addition, the CNGA performs better than the standard genetic algorithm—besides, the CNGA helps to better understand the properties of land change dynamics within a given landscape. [less ▲]

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See detailRésilience urbaine et risque d’inondation : apports du numérique et de l’expérimental
Dewals, Benjamin ULiege; Erpicum, Sébastien ULiege; Archambeau, Pierre ULiege et al

Scientific conference (2017, December 07)

L’urbanisation croissante et l’intensification des extrêmes hydrologiques accentuent l’importance de la gestion du risque d’inondation. Différents mesures en matière d’aménagement du territoire peuvent ... [more ▼]

L’urbanisation croissante et l’intensification des extrêmes hydrologiques accentuent l’importance de la gestion du risque d’inondation. Différents mesures en matière d’aménagement du territoire peuvent contribuer à maîtriser la vulnérabilité accrue des zones construites, mais leurs effets sont rarement quantifiés de manière objective. Nous montrerons des exemples d’analyse prospective de l’évolution du risque d’inondation pour différents scénarios d’urbanisation. Les nouvelles constructions affectent non seulement la vulnérabilité dans les plaines inondables, mais également les écoulements d’inondation. Une analyse systématique de l’impact hydrologique de choix en matière d’aménagement de la ville sera présentée. Des implications pratiques en matière de résilience des tissus urbains seront mises en évidence. Nous soulignerons également la complémentarité entre modélisation numérique et expérimentale sur cette thématique, ainsi que l’importance des incertitudes qui affectent de façon contrastée les différentes étapes de la modélisation et présentent une hétérogénéité spatiale à ne pas négliger. [less ▲]

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