References of "Mustafa, Ahmed Mohamed El Saeid"
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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 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)

Flooding in urban areas is an increasing problem and it causes over one-third of overall economic losses due to natural hazards across the globe. For many river basins, studies show that flood risk will ... [more ▼]

Flooding in urban areas is an increasing problem and it causes over one-third of overall economic losses due to natural hazards across the globe. For many river basins, studies show that flood risk will further increase during the 21st century as a result of a combination of climate change and urban development. It is important in this respect to evaluating flood risks at different time horizons by coupling urban development models with hydrological models. Although often focused on flood hazard only, the existing studies suggest (i) an overwhelming contribution of urbanization to the future increase in flood risk in some river basins, and (ii) a likely high influence of small-scale spatial patterns in future urbanization, requiring analyses at a finer scale than performed so far. The main goal of this PhD thesis is to investigate the expected flood damage for possible future built-up patterns at different scales. Wallonia (Belgium) is selected as a case study for this thesis. Four main steps are followed to accomplish the thesis’ goal. First, this thesis takes a retrospective analysis of the evolution of the urban development in Wallonia through the use of a multinomial logistic regression model (MNL). Second, in order to estimate the future flood damage for urban areas, there is a need for urbanization scenarios that are based on a realistic land-use change model. In this context, this research proposes and compares two land-use change models: (i) a coupled MNL and cellular automata model (MNL-CA), and (ii) a coupled CA and agent-based model (CA-AB). Based on the comparison of both modeling approaches, the CA-AB model is employed to simulate several future urbanization scenarios. These scenarios are typically considering long-term time horizons, i.e. 2050-2100, as this is the appropriate time frame for analyzing such effects. In this thesis, Belgian cadastral datasets for 1990, 2000 and 2010 are used to calibrate and validate the land-use change models. A remarkable feature of this research is that it considers multiple densities of built-up which enables us 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, one of the main themes of this thesis is attributed to the modeling of uncertainty in the land-use change models. Third, 24 urbanization scenarios for the entire Wallonia for 2030, 2050, 2070 and 2100 that differed in terms of the rate of development and spatial policies are generated. The simulated scenarios will then be integrated with a hydrological model for the same time horizon. The inundation extents and water depths for each scenario are determined by a hydraulic model for steady flows corresponding to return periods of 25, 50 and 100 years. The results suggest that urban development will continue within flood hazard zones in many of the simulated scenarios. Therefore, fourth, 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 hazard zones. The results pointed out that the assumption of a binary approach of urbanization modeling, urban vs non-urban, may lead to inaccurate conclusions as the relative importance of the development controlling factors typically varies with density. Our results show that the densification strategy, without spatial policy interventions, may lead to an increase in the flood absolute damage by a 100% at the end of the century. Another important finding of this thesis is that the geometric factors of urban layouts, such as road width, orientation or curvature, have a role in water flow properties during floods. Thus, the thesis provides some guidelines for designing flood-sensitive urban layouts. [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)

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 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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