1,387 research outputs found
An evaluation of geographical information systems for surface water studies in the Badia region of Jordan
Three applications of Geographical Information Systems for surface water studies in the Badia region of Jordan are presented, hi the first application, a Digital Elevation Model (DEM) of the study area was generated from the available contour maps. The channel drainage network was enforced into the created DEM to ensure accurate emplacement of the extracted drainage network. The channel drainage network was extracted from the DEM at a threshold value of 250 pixels. At this threshold, the drainage density of the extracted channel network is equivalent to the wadis network on the topographic maps In the second application, a hydrologically-oriented GIS database was developed. The database aimed to provide detailed description of the watershed characteristics and the hydrological processes relevant to surface water studies. A menu-driven application was built on the database to extract and analyse the database information at the sub- watershed level. The third application involved building a spatial model for generating surface runoff hydrographs from the rainfall data. The model applies GIS data structure and the raster processing techniques to simulate the rainfall-excess generation and flow routing processes. The distributed structure of the model allows for representing the hydrological processes and modelling the watershed response at the level of details that fits the resolution of the available data
Transport and urban environment in developing countries: the situation is known, pragmatic policies and understanding of related elements are needed
Environmental impacts of urban transport in developing countries are well known as indicated through many examples from Africa, Asia and Latin America. Policies and countermeasures are classified and listed as well as the numerous involved actors, variables and effects. A pragmatic approach is needed to ensure success and sustainability of the solutions. The paper discusses main barriers impeding applicability, success and sustainability of mitigation policies and countermeasures. It also outlines the complexity of handling and modelling such multivariate problem of policies, actors, variables and effects. A simplified approach is suggested, which can ensure applicability, implement-ability, success and sustainability of policies and countermeasures. The paper addresses the need to achieve balance between facing the problem with “immediate vision” and the importance of looking to “future needs”, between “simplifying the analysis” and “comprehensiveness” and between the ambition of setting out “ideal objectives and policies” and the importance of being “pragmatic” in view of the prevailing city constraints. Recommended practical directions on designing achievable objectives and policies are given
Deep Learning-based Polyp Detection in Wireless Capsule Endoscopy Images
Gastrointestinal (GI) system diseases have increased significantly, where colon and rectum cancer is considered the second cause of death in 2020. Wireless Capsule Endoscopy (WCE) is a revolutionary procedure for detecting Colorectal lesions. It was automatically used to detect the polyps, multiple SB lesions, bleeding, and Ulcer. The acquired video by the WCE can be processed using a Computer-Aided Diagnosis (CAD) system. However, such videos suffer several problems, including burling, high illumination. and distortion. These effects obligate the development of image processing techniques of high accuracy in detection using deep learning-based segmentation. In this paper, a transfer learning-based U-Net was proposed to transfer the knowledge between the medical images in the training phase and the subsequent segmentation using transfer learning to achieve better results and high accuracy results compared to other related studies. The improvement is done by using an algorism written in python code The results showed average segmentation accuracy of 98.67
Development of sensing concrete: principles, properties and its applications
YesSensing concrete has the capability to sense its condition and environmental changes, including stress (or force),
strain (or deformation), crack, damage, temperature and humidity through incorporating functional fillers. Sensing
concrete has recently attracted major research interests, aiming to produce smart infrastructures with elegantly
integrated health monitoring abilities. In addition to having highly improved mechanical properties, sensing concrete
has multifunctional properties, such as improved ductility, durability, resistance to impact, and most importantly self-health monitoring due to its electrical conductivity capability, allowing damage detection without the need of an
external grid of sensors. This tutorial will provide an overview of sensing concrete, with attentions to its principles,
properties, and applications. It concludes with an outline of some future opportunities and challenges in the application
of sensing concrete in construction industry.National Science Foundation of China (51978127 and 51908103), the China Postdoctoral Science Fundation (2019M651116) and the Fundamental Research Funds for the Central Universities in China (DUT18GJ203).National Science Foundation of China (NSFC) (Nos. 51978127 and 51908103), the China Postdoctoral Science Foundation (No. 2019M651116), and the Fundamental Research Funds for the Central Universities in China (No. DUT18GJ203)
Modified Canny Detector-based Active Contour for Segmentation
In the present work, an integrated modified canny detector and an active contour were proposed for automated medical image segmentation. Since the traditional canny detector (TCD) detects only the edge’s pixels, which are insufficient for labelling the image, a shape feature was extracted to select the initial region of interest ‘IROI’ as an initial mask for the active contour without edge (ACWE), using a proposed modified canny detector (MCD). This procedure overcomes the drawback of the manual initialization of the mask location and shape in the traditional ACWE, which is sensitive to the shape of region of region of interest (ROI). The proposed method solves this problem by selecting the initial location and shape of the IROI using the MCD. Also, a post-processing stage was applied for more cleaning and smoothing the ROI. A practical computational time is achieved as the proposed system requires less than 5 minutes, which is significantly less than the required time using the traditional ACWE. The results proved the ability of the proposed method for medical image segmentation with average dice 87.54%
Modified Canny Detector-based Active Contour for Segmentation
In the present work, an integrated modified canny detector and an active contour were proposed for automated medical image segmentation. Since the traditional canny detector (TCD) detects only the edge’s pixels, which are insufficient for labelling the image, a shape feature was extracted to select the initial region of interest ‘IROI’ as an initial mask for the active contour without edge (ACWE), using a proposed modified canny detector (MCD). This procedure overcomes the drawback of the manual initialization of the mask location and shape in the traditional ACWE, which is sensitive to the shape of region of region of interest (ROI). The proposed method solves this problem by selecting the initial location and shape of the IROI using the MCD. Also, a post-processing stage was applied for more cleaning and smoothing the ROI. A practical computational time is achieved as the proposed system requires less than 5 minutes, which is significantly less than the required time using the traditional ACWE. The results proved the ability of the proposed method for medical image segmentation with average dice 87.54%
Recommended from our members
Influence of Shear Reinforcement on Reinforced Concrete Continuous Deep Beams
yesTest results of 24 reinforced concrete continuous deep beams are reported. The main variables studied were concrete strength, shear span-to-overall depth ratio (a/h) and the amount and configuration of shear reinforcement. The results of this study show that the load transfer capacity of shear reinforcement was much more prominent in continuous deep beams than in simply supported deep beams. For beams having an a/ h of 0.5, horizontal shear reinforcement was always more effective than vertical shear reinforcement. The ratio of the load capacity measured and that predicted by the strutand-tie model recommended by ACI 318-05 dropped against the increase of a/h. This decrease rate was more remarkable in continuous deep beams than that in simple deep beams. The strut-and-tie model recommended by ACI 318-05 overestimated the strength of continuous deep beams having a/ h more than 1.0
Recommended from our members
Influence of Type and Replacement Level of Recycled Aggregates on Concrete Properties.
yesTest results of nine recycled aggregate concretes and a control concrete using only natural aggregates are reported. The recycled aggregates used were classified into three different types according to their measured specific gravity and water absorption, namely, RG I for recycled coarse aggregate having a specific gravity of 2.53 and water absorption of 1.9%; RG III for recycled coarse aggregate having a specific gravity of 2.4 and water absorption of 6.2%; and RS II for recycled fine aggregate having a specific gravity of 2.36 and water absorption of 5.4%. The replacement levels of both recycled coarse and fine aggregates were 30, 50, and 100% in separate mixtures. Slump loss and the amount of bleeding with time were recorded for fresh concrete. Compressive and tensile strengths, moduli of rupture and elasticity, and unrestrained shrinkage strain were also measured for hardened concrete. The properties of fresh and hardened concrete tested, together with a comprehensive database reported in the literature, were evaluated with respect to the relative water absorption of aggregates combining the quality and volume of recycled aggregates used. In addition, the properties of hardened concrete with different replacement levels and quality of recycled aggregates were compared with the design equations of ACI 318-05 and empirical equations proposed by Oluokun for natural aggregate concrete, whenever possible. Test results clearly showed that the properties of fresh and hardened concrete containing recycled aggregates were dependent on the relative water absorption of aggregates. In addition, the moduli of rupture and elasticity of recycled aggregate concrete were lower than the design equations specified in ACI 318-05, when the relative water absorption of aggregates is above 2.5% and 3.0%, respectively
- …