Impact of urban expansion on potential flooding, storage and water harvesting in the city of Sharjah, United Arab Emirates

The work presented in this article is an extension of an earlier study [1] in which runoff in the city of Sharjah, United Arab Emirates (UAE), was assessed for the period 1967–2010. In this study, the impacts of urban expansion on potential flooding, storage and water harvesting were assessed for the period 1976–2016 using rainfall data recorded during the same period. Sharjah is a generally a flat coastal city that is located in a dry hot region average rainfall of approximately 100 mm/y. Remote sensing and GIS techniques were used to assess the expansion of built areas in the city using multi-temporal Landsat satellite images. The built areas in the city increased during the study period by approximately four folds while the population increased by more than 10 folds. The study results demonstrate the historical increase in runoff potential, flooding potential and runoff coefficient and decline in water storage potential. The results are consistent with the observed incidence of significant local flooding episodes in urban areas during rainfall events. Furthermore, an assessment of potential urban water harvesting based on expansion of built areas in the city is provided and appropriate urban storm water management practices for the city are recommended

Monitoring of Dead Sea water surface variation using multi-temporal satellite data and GIS.

Remote sensing (RS) and geographic information systems (GIS) are very useful for environmental-related studies, particularly in the field of surface water studies such as monitoring of lakes. The Dead Sea is exposed to very high evaporating process with considerable scarcity of water sources, thus leading to a remarkable shrinkage in its water surface area. The lake suffers from dry out due to the negative balance of water cycle during the previous four decades. This paper discusses the application of RS, GIS, and Global Positioning System to estimate the lowering and the shrinkage of Dead Sea water surface over the period 1810–2005. A set of multi-temporal remote sensing images were collected and processed to show the lakes aerial extend shrinkage from 1973 up to 2004. Remote sensing data were used to extract spatial information and to compute the surface areas for Dead Sea for various years. The current study aims at estimating the fluctuation of Dead Sea level over the study period with special emphasis on the environmental impact assessment that includes the degradation level of the Dead Sea. The results indicated that there is a decrease of 20 m in the level of the Dead Sea that has occurred during the study period. Further, the results showed that the water surface area of the Dead Sea has shrunk from 934.26 km2 in 1973 to 640.62 km2 in 2004

Shear behavior of steel fiber reinforced concrete using full-field displacements from digital image correlation

Reinforced concrete beams with discrete hooked-end steel fibers at 0.5% volume fraction are tested with a shear span to depth (a/d) ratio equal to 1.8. Digital image correlation (DIC) technique was used to obtain the full-filed displacements from the beam. The formation and propagation of a shear crack which directly influences the load response and the peak load in the load response of the beam is monitored using the displacement information available from DIC. There is a continuous increase in slip across the crack faces with increasing load, which produces an increase in the crack opening. The dilatant behavior indicated by the proportion of crack opening to slip displacement obtained from the control and the SFRC beams is identical. Failure in control beams is brittle and was produced by the opening of dominant shear crack within the shear span. At the peak load, the shear crack pattern in fiber reinforced concrete is identical to the crack pattern in the control beam. The fiber reinforced concrete beams exhibit post peak load carrying capacity with continued slip of the dominant shear crack. The crack bridging stress provided by the fibers results in a significant increase shear transfer across the crack which provides significant post-peak load carrying capacity with increasing slip of the shear crack

UNIVERSITY OF CALGARY Semi-Automatic Registration of Multi-Source Satellite Imagery with Varying Geometric Resolutions

Image registration concerns the problem of how to combine data and information from multiple sensors in order to achieve improved accuracy and better inferences about the environment than could be attained through the use of a single sensor. Registration of imagery from multiple sources is essential for a variety of applications in remote sensing, medical diagnosis, computer vision, and pattern recognition. In general, an image registration methodology must deal with four issues. First, a decision has to be made regarding the choice of primitives for the registration procedure. The second issue concerns establishing the registration transformation function that mathematically relates images to be registered. Then, a similarity measure should be devised to ensure the correspondence of conjugate primitives. Finally, a matching strategy has to be designed and implemented as a controlling framework that utilizes the primitives, the similarity measure, and the transformation function to solve the registration problem. The Modified Iterated Hough Transform (MIHT) is used as the matching strategy for automatically deriving an estimate of the parameters involved in the transformation function as well a

Semi-automatic registration of multi-source satellite imagery with varying geometric resolutions

Bibliography: p. 129-135Image registration concerns the problem of how to combine data and information from multiple sensors in order to achieve improved accuracy and better inferences about the environment than could be attained through the use of a single sensor. Registration of imagery from multiple sources is essential for a variety of applications in remote sensing, medical diagnosis, computer vision, and pattern recognition. In general, an image registration methodology must deal with four issues. First, a decision has to be made regarding the choice of primitives for the registration procedure. The second issue concerns establishing the registration transformation function that mathematically relates images to be registered. Then, a similarity measure should be devised to ensure the correspondence of conjugate primitives. Finally, a matching strategy has to be designed and implemented as a controlling framework that utilizes the primitives, the similarity measure, and the transformation function to solve the registration problem. The Modified Iterated Hough Transform (MIHT) is used as the matching strategy for automatically deriving an estimate of the parameters involved in the transformation function as well as the correspondence between conjugate primitives. The MIHT procedure follows an optimal sequence for parameter estimation. This sequence takes into account the contribution of linear features with different orientations at various locations within the imagery towards the estimation of the transformation parameters in question. Accurate co-registration of multi-sensor datasets is captured at different times is a prerequisite step for a reliable change detection procedure. Once the registration problem has been solved, the suggested methodology proceeds by detecting changes between the registered images. Derived edges from the registered images are used as the basis for change detection. Edges are utilized because they are invariant regardless of possible radiometric differences between the images in question. Experimental results using real data proved the feasibility and robustness of the suggested approach

Geomatics for Rehabilitation of Mining Area

Mining activities often cause dramatic changes in landscapes, particularly in the dump sites and its surrounding environment. Land rehabilitation is the process of renovating damaged land to some extent of its original shape and aims to minimize and mitigate the environmental effects to allow new land uses. The success of different rehabilitation strategy and newly suggested urban and architecture modeling depends on the landscape characterization (topography of the study area and its derivatives such as slope and aspects, geological and geomorphologic nature of the study area). The aim of this study is to demonstrate the utility of different methodologies based on geomatics techniques (Photogrammetry, Remote Sensing, Global Positioning System (GPS) and three dimensional Geographic Information System (GIS)) for highlighting landscape characterization which is needed for rehabilitation of Mahis area. Photogrammetric adjustment procedures were used to create digital elevation model and Orth-Photo model for the study area using aerial images. Remote sensing data were used for land classification to provide vital information for rehabilitation planning. GPS field observations were used to build spatial network for the study area based on ground control point collections. Finally, realistic representation of the study area with three dimensiona

Geomatics for Mapping of Groundwater Potential Zones in Northern Part of the United Arab Emiratis - Sharjah City

In United Arab Emirates (UAE) domestic water consumption has increased rapidly over the last decade. The increased demand for high-quality water, create an urgent need to evaluate the groundwater production of aquifers. The development of a reasonable model for groundwater potential is therefore crucial for future systematic developments, efficient management, and sustainable use of groundwater resources. The objective of this study is to map the groundwater potential zones in northern part of UAE and assess the contributing factors for exploration of potential groundwater resources. Remote sensing data and geographic information system will be used to locate potential zones for groundwater. Various maps (i.e., base, soil, geological, Hydro-geological, Geomorphologic Map, structural, drainage, slope, land use/land cover and average annual rainfall map) will be prepared based on geospatial techniques. The groundwater availability of the basin will qualitatively classified into different classes based on its hydro-geo-morphological conditions. The land use/land cover map will be also prepared for the different seasons using a digital classification technique with a ground truth based on field investigation

Multi-Temporal satellite imagery for infrastructure growth assessment of Dubai City, UAE

Throughout the past few decades, Dubai City has witnessed massive growth in its urban area and infrastructure facilities. The discovery of oil and gas in the Emirate significantly played a role for such a rapid growth. Given this fact and the short time-period for such an expansion, it is crucial to develop an understanding of the patterns of the development in the City, where policy-makers, researchers, and concerned authorities would gain better vision and strategy for the future. Recent advances in satellite imagery in terms of improved spatial and temporal resolutions are allowing for efficient identification of change patterns and the prediction of areas of growth. This study aims to quantify and analyse the spatial–temporal urbanization that took place in Dubai City throughout the past decades (specifically from early 1970’s until 2015). Multi temporal satellite images with various geometric and radiometric resolutions will be utilized for this purpose. The suggested methodology consists of a sequence of image processing techniques that include supervised and unsupervised classification. Subsequently, the classified images were utilized to quantify the urbanization of the City. The results show that since 1970, the urbanization and population have been dramatically increased by 5 and 12 times respectively. The resulting trend can be potentially used to evaluate the consequences of massive urban development, such as City infrastructure, water, environmental and the social impact