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Regional debris flow susceptibility analysis in mountainous peri-urban areas through morphometric and land cover indicators
Published in María Carolina Rogelis Prada, Operational Flood Forecasting, Warning and Response for Multi-Scale Flood Risks in Developing Cities, 2020
This subsection includes the development of the morphometric indicator model based on the principal component analysis and the assessment of the appropriateness of the morphometric indicator. The latter covers the classification of watersheds according to the debris flows propagation capacity and the comparison of the morphometric indicator with the propagation of debris flows described using the MSF model; with the 11 watersheds with confirmed flow type in the study area; and with three additional watersheds with confirmed flow type outside the study areas. The second subsection shows the results of the development of the land cover indicator and finally the third subsection shows the results of the combination of the morphometric indicator and the land cover indicator to obtain a final susceptibility index.
Big Data Era in Magnetic Resonance Imaging of the Human Brain
Published in Ervin Sejdić, Tiago H. Falk, Signal Processing and Machine Learning for Biomedical Big Data, 2018
Xiaoyu Ding, Elisabeth de Castro Caparelli, Thomas J. Ross
Different characteristics of brain tissue, such as shape, size, and density, are evaluated using structural images. Morphometric techniques, such as volume/density (for example, voxel-based morphometry) [1] and cortical thickness [2], are commonly used to measure the volume or shape of gray matter tissue, while changes in white matter volumes provide some information about possible inflammation, edema, or demyelination. Additional information on the white matter quality is mostly obtained by using diffusion-weighted MRI techniques.
Augmented Statistical Shape Modeling for Orthopedic Surgery and Rehabilitation
Published in de Azevedo-Marques Paulo Mazzoncini, Mencattini Arianna, Salmeri Marcello, Rangayyan Rangaraj M., Medical Image Analysis and Informatics: Computer-Aided Diagnosis and Therapy, 2018
Bhushan Borotikar, Tinashe Mutsvangwa, Valérie Burdin, Enjie Ghorbel, Mathieu Lempereur, Sylvain Brochard, Eric Stindel, Christian Roux
This work reports on an integrated pipeline for building an automated, unbiased global SSM of the scapula and humerus for morphometric as well as segmentation purposes. The chapter also explains the methodology to build augmented SSMs to be used for clinical diagnosis. Validity of such augmented SSMs is also determined using a global, as well as local, validation methodology. Scapula bone is especially focused on, as attempts to date to build models of this bone have evaded automation, as in [32], which required manual landmarking to initialize the B-spline-based non-rigid registration. Another reported attempt [33] did not present a global model, which required watershed segmentation in order to constraint the anatomical correspondence. This chapter first briefs the development of an SSM-building pipeline for anatomical bone shapes in detail. This is done to thoroughly understand the techniques used for various steps involved in the SSM building. The remainder of this chapter is arranged as follows. The second section explains how bone models are constructed from computed tomography (CT) data by using semiautomatic segmentation approach. The third section explains different registration methods and gives a detailed account of the rigid and non-rigid registration techniques used in this chapter. The fourth section explains construction of SSMs using registered sample sets that are in correspondence. The fifth section evaluates the robustness of the methods employed to build the SSM using the measures of generality, specificity, and compactness. The sixth section explains the development of augmented SSM using anatomical landmarks in order to use the statistical shape model as a clinical and surgical tool. The seventh section discusses the proposed application of such augmented SSMs in computer-aided surgery and pre-surgical planning.
Assessment and analysis of morphometric characteristics of Lake Tana sub-basin, Upper Blue Nile Basin, Ethiopia
Published in International Journal of River Basin Management, 2023
Bitew G. Tassew, Mulugeta A. Belete, K. Miegel
Three main morphometric aspects are used in the study namely: Linear, areal and relief aspects. The results of the study demonstrate that the morphometric parameters expressed the hydrological, lithological, geomorphological, slope, relief and land use/land cover conditions of the basin. From this study, the following conclusions have been made: The Lake Tana Sub-basin is a seventh order stream with a dendritic pattern having 9891 streams (total length of 9222.36 km). It has a mean stream length of 5.04 km. A bifurcation ratio of 22.7 is obtained and this reveals a low degree of drainage integration in the sub-basin, presence of high number of streams even in the higher orders, high structural disturbance, availability of erodible soils and occurrence of high overland flow and discharge.The sub-basin is characterized with lower drainage density (0.62), low stream frequency (0.66), fine drainage texture (11.04), elongated and low class with an elongation and circulatory ratio value of 0.7 and 0.23, respectively which reveals coarse drainage texture, permeable subsurface, homogeneous geological material, high precipitation and infiltration rate and high vegetation cover.The sub-basin has a very low relief ratio (0.007) which shows overall erosion and degradation level and considered as relatively small. It has a high value of ruggedness number (1.4) reveals susceptibility to flash floods and soil erosion.
Surface drainage features identification using LiDAR DEM smoothing in agriculture area: a study case of Kebumen Regency, Indonesia
Published in International Journal of Image and Data Fusion, 2023
Hepi H. Handayani, Arizal Bawasir, Agung B. Cahyono, Teguh Hariyanto, Husnul Hidayat
The morphometric analysis included two aspects which were linear and areal. The linear aspect contained the characteristics of the streamflow in the drainage network. While the areal aspect contained the characteristics of the watershed and its relation to the stream. The drainage networks and watersheds produced by the smoothed DEM of FPDEM-S and EPDEM-S were not visually different (Figure 9a,b). The differences were presented quantitatively on the areal morphometric parameters result. However, streams and watershed produced by DEMNAS showed different patterns (Figure 9c).
Identification of erosion-prone areas using modified morphometric prioritization method and sediment production rate: a remote sensing and GIS approach
Published in Geomatics, Natural Hazards and Risk, 2019
Ajaykumar K. Kadam, Tasadoq H. Jaweed, Sanjay S. Kale, Bhavana N. Umrikar, Rabindranath N. Sankhua
This study emphasizes the behaviour of drainage network system which includes the spatial relationship among streams or rivers influenced by inequalities of slope, soil, rock resistance factor, structure and geologic history of the region. The morphometric analysis includes linear, areal and relief parameters, discussed in the following paragraphs.