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Revealing the natural complexity of fluvial morphology through 2d hydrodynamic delineation of river landforms

GEOMORPHOLOGY 2014年 210卷 14-22页

作者： Wyrick, J. R. Senter, A. E. Pasternack, G. B. Univ Calif Davis Dept Land Air & Water Resources Davis CA 95616 USA

Fluvial landforms at the morphological-unit scale (similar to 1-10 channel widths) are typically delineated and mapped either by breaking up the one-dimensional longitudinal profile with no accounting of lateral variations or by manually classifying surface water patterns and two-dimensional areal extents in situ or with aerial imagery. Mapping errors arise from user subjectivity, varying surface water patterns when the same area is observed at different discharges and viewpoints, and difficulty in creating a complete map with no gaps or overlaps in delineated polygons. This study presents a new theory for delineating and mapping channel landforms at the morphological-unit scale that eliminates in-field subjective decision making, adds full transparency for map users, and enables future systemic alterations without having to remap in the field. delineation is accomplished through a few basic steps. First, near-census topographic and bathymetric data are used in a two-dimensional hydrodynamic model to create meter-scale depth and velocity rasters for a representative base flow. Second, expert judgment and local knowledge determine the number and nomenclature of landform types as well as the range of base flow depth and velocity over each type. This step does require subjectivity, but it is transparent and adjustable at any time. Third, the hydraulic landform classification is applied to hydraulic rasters to quickly, completely, and objectively map the planform pattern of laterally explicit landforms. Application of this theory will reveal the true natural complexity, yet systematic organization, of channel morphology. (C) 2013 Elsevier B.V. All rights reserved.

关键词： Morphological units Fluvial landforms Fluvial geomorphology 2d modeling

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3d Stratum modeling Based on Profile Reconstruction

3D Stratum Modeling Based on Profile Reconstruction

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International Conference on Computer Science and Education (CSE 2011)

作者： Yu, Nian Zhao, Ning Chengdu Univ Technol Key Lab Earth Explorat & Informat Technol MOE Chengdu Peoples R China China railway Eryuan Engn Grp CO LTD Chengdu Peoples R China Henan Polytecn Univ Coll Comp Sci & Technol Jiaozuo Peoples R China

ISBN: (纸本)9783642224553

In the fields of petroleum exploration and engineering geology, complex 3d stratum model is always necessary to be constructed and used for analogue calculation or geological study. On the basis of analyzing features of 31) stratum modeling, this paper proposes a set of complete 3d stratum modeling algorithm based on the profile reconstruction. The algorithm can help the user to carry out interactive modeling by using the existing data simply with a high efficiency, and to construct complex model having fault: therefore, it has good practicability.

关键词： 2d modeling 3d modeling block track delaunay Triangulation

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2d FEM model for BCI probe-to-cables coupling with several conductors at the secondary winding

2D FEM model for BCI probe-to-cables coupling with several c...

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International Symposium on Electromagnetic Compatibility - EMC EUROPE

作者： diop, M. S. Cheaito, H. Clavel, E. Vollaire, C. Vialardi, E. Galli, E. Mutel, L. Gainetdinoff, B. Univ Grenoble Alpes CNRS Grenoble INP G2Elab F-38000 Grenoble France Univ Lyon Ecole Cent Lyon CNRS Lab AmpereUMR5005 Ecully France ALTAIR Meylan France AVNIR Engn Valence France Grenoble INP Esisar Plateforme Esynov Valence France

ISBN: (纸本)9781538606896

Electronic equipment designed to be installed onto aircraft must be certified in accordance with established EMC standards. This paper is focused on section 20 of RTCA-dO160 which refers to conducted susceptibility in aeronautics. Since equipment can succeed or not in qualification test, aim is to be able to predict these levels of disturbance for limiting costs and time design. Moreover, aircraft manufacturers are mostly looking for precise answers about the sensitivity and reproducibility of these tests. In this sense, a 2d model of probe coupling to wires is developed in this work.

关键词： BCI 2d modeling probe to cables coupling validation with measurement

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Comparative Analysis of 2d and 3d Permanent Magnet Synchronous Motor Models Under demagnetization Conditions 116

Comparative Analysis of 2D and 3D Permanent Magnet Synchrono...

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2024 International Annual Conference of the Italian Association of Electrotechnics

作者： Garaci, Shiva Lai, Chanyan Iyer, Lakshmi Varaha Concordia Univ Elect & Comp Engn Montreal PQ Canada R&D Illagna Int Inc Troy NY USA Corp Engn Troy NY USA

ISBN: (纸本)9798350378498;9788887237627

The increasing industrial and research interest in Permanent Magnet Synchronous Motors (PMSMs) highlights the need for accurate performance evaluation methods. Analyzing PMSM performance using two-dimensional (2d) and three-dimensional (3d) magnetic field analysis with the finite element method (FEM) is both complex and time-consuming. The accuracy of 2d analysis results has always been a topic of debate, raising questions about the preferred type of analysis for specific motor applications. This study presents a comparative analysis of 2d and 3d models of PMSMs under demagnetization conditions. Both partial and uniform demagnetization scenarios are examined to assess their impact on key magnetic quantities. The research focuses on evaluating the electromagnetic torque, flux linkage, and back electromotive force (hack-EMF) in both 2d and 3d models. Results indicate significant differences in the magnetic performance between the two modeling approaches under demagnetization, providing insights into the accuracy and reliability of each method. This study aims to enhance the understanding of PMSM behavior in degraded magnetic states with both 2d and 3d models.

关键词： demagnetization finite element permanent magnet synchronous motor 2d modeling 3d modeling

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A 2d Forward Gravimetry Problem for a Polygon with Parabolic density

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MOSCOW UNIVERSITY GEOLOGY BULLETIN 2019年第5期74卷 516-520页

作者： Chepigo, L. S. Lygin, I. V. Bulychev, A. A. Moscow MV Lomonosov State Univ Dept Geol Moscow 119991 Russia

This article describes the formula of gravity of a polygon with a density varying according to a parabolic law (2d model). Calculation of gravity according to this formula can be made for both the external and interna... 详细信息

关键词： gravity modeling variable density 2d modeling

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A method of shadow puppet figure modeling and animation

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Frontiers of Information Technology & Electronic Engineering 2015年第5期16卷 367-379页

作者： Xiao-fang HUANG Shou-qian SUN Ke-jun ZHANG Tian-ning XU Jian-feng WU Bin ZHU College of Computer Science and Technology Zhejiang University School of Art Zhejiang University of Technology College of Information Science and Technology Zhejiang Shuren University

To promote the development of the intangible cultural heritage of the world, shadow play, many studies have focused on shadow puppet modeling and interaction. Most of the shadow puppet figures are still imaginary,spread by ancients, or carved and painted by shadow puppet artists, without consideration of real dimensions or the appearance of human bodies. This study proposes an algorithm to transform 3d human models to 2d puppet figures for shadow puppets, including automatic location of feature points, automatic segmentation of 3d models, automatic extraction of 2d contours, automatic clothes matching, and animation. Experiment proves that more realistic and attractive figures and animations of the shadow puppet can be generated in real time with this algorithm.

关键词： Shadow play Shadow puppet figure 3d human body data processing 2d modeling

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development, Calibration, and Validation of a High-Resolution 2d HEC-RAS Model at St. Arbor Wetland to Extract Rating Curves at Levee Breach Locations

Development, Calibration, and Validation of a High-Resolutio...

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作者： Martin, Mackenzie T. Tennessee Technological University

学位级别：M.S., Master of Science/Master of Surgery

Wetlands improve water quality, protect floodplains and food crops, provide habitat to flora and fauna, and recharge groundwater. To protect, restore, and enhance the functions and values of wetland ecosystems, the Natural Resources Conservation Service initiated the Wetland Reserve Program (WRP). Easements enrolled in the WRP are currently being evaluated by multiple universities and organizations. One particular WRP easement is St. Arbor, located in Carlisle County, Kentucky. It is important to quantify the available water in a given easement to properly evaluate wetland restoration. One way to represent the quantity of water in an easement is through a hydrologic budget that represents the inflows and outflows of a given control volume. developing a hydrologic budget requires a vast amount of flow data, which can be difficult to capture for a longer time scale. A hydrodynamic model, specifically the Hydraulic Engineering Center River Analysis System, or HEC-RAS, can quantify flow and produce rating curves at selected locations, providing a stage-discharge relationship. These stage-discharge rating curves can be coupled with stage data to determine flow at a selected location to produce the hydrologic budget. Therefore, the objective of this study was to develop, calibrate, and validate a high-resolution 2d HEC-RAS model at Mayfield ditch to extract rating curves at the selected locations. The 2d HEC-RAS model was developed using high-resolution topographic data, water level data, and land use/land cover data. The model was calibrated for high and low flows by comparing a selection of simulated hydrographs to observed hydrographs, at a location downstream from the levee breaches, and using published metrics to rate the calibration. The model was then validated for high and low flows using a separate data period than the calibration. Validation occurred at each levee breach and spatially as an inundation boundary. Rating curves were extracted at each levee breach w

关键词： 2d modeling Levee breach modeling Rating curves Wetland

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Electrical resistivity and magnetic methods in mapping groundwater on the western margin of the Central Main Ethiopian Rift- A case study in the Belesa area, eastern Lemmo Woreda, Ethiopia

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ACTA GEOdAETICA ET GEOPHYSICA 2024年第4期59卷 441-461页

作者： Yehualaw, Esubalew Haile, Tigistu Mickus, Kevin Beardsmore, Graeme Nigusse, Wubamlak Addis Ababa Univ Sch Earth Sci Addis Ababa Ethiopia Ethiopian Minist Mines Dept Petr & Geothermal POB 486 Addis Ababa Ethiopia Missouri State Univ Sch Earth Environm & Sustainabil Springfield MO 65897 USA Univ Melbourne Sch Geog Earth & Atmospher Sci Parkville Australia Bahir Dar Univ Sch Earth Sci Bahir Dar Ethiopia

Vertical electrical sounding (VES) and magnetic data were analyzed to infer the groundwater system in the Belesa area within the central Main Ethiopian Rift. The analysis is aimed at aiding in determining the groundwater potential for current and future development of groundwater resources within the Belesa area. The analysis of two-dimensional magnetic forward and one-dimensional electrical inverse models aided in locating faults, fractures, and lithological units that may contain groundwater. Lithological logs from nearby boreholes where lithological units had been determined were used to constrain the magnetic and VES models. The VES models and a magnetic derivative (tilt and horizontal) analysis mapped the existence of several possible fractures and faults that may act as either barriers or conduits for groundwater movement. The magnetic and electrical resistivity models indicated a potential aquifer associated with low electrical resistivity values occurring between 120 and 240 m in depth within the weathered and fractured ignimbrites which are bounded by faults, plus an additional potential deeper aquifer within a sandy pumice layer. Low electrical resistivity horizons provide targets for future drilling for water and a base for geophysical surveys that would further delineate the groundwater system in the Belesa area.

关键词： Electrical resistivity Magnetics Aquifers Groundwater potential 2d modeling

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Two-dimensional approach for the numerical simulation of large bore reciprocating compressors thermodynamic cycle

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APPLIEd THERMAL ENGINEERING 2018年 129卷 490-501页

作者： Balduzzi, Francesco Tanganelli, Andrea Ferrara, Giovanni Babbini, Alberto Univ Florence Dept Ind Engn Via Santa Marta 3 I-50139 Florence Italy Baker Hughes Via F Matteucci 2 I-50127 Florence Italy

The performance of large reciprocating compressors is strongly dependent on the geometry of gas chambers and valve pockets, both directly influencing the pressure losses along the flow path. Reliable and accurate numerical models are necessary for a proper prediction of the thermodynamic cycle of the compressor, hence of both the efficiency and the absorbed power. In order to account for the effect of the geometrical features, the detail level of the modeling technique needs to be suitable for capturing the most significant phenomena related to the physics involved. To this end, CFd simulations can represent a viable tool for the analysis of the working cycle. due to the complexity of the geometry and the large extent of the fluid domain, unsteady three-dimensional CFd simulations are very demanding in terms of computational resources, resulting in unreasonably lengthy simulations and specialized hardware requirements. The present paper describes a two-dimensional CFd modelling strategy aimed at reducing the computational effort by ensuring a compromise between the accuracy of the results and the simulation costs. A simplified geometry is used to allow the reduction of the three-dimensional fluid domain to an equivalent two-dimensional representation. The suitability of using two-dimensional models for the numerical simulation of the thermodynamic cycle of large reciprocating compressors is analyzed and discussed. In the paper, the simulation results of a double-acting large bore cast iron cylinder are compared to experimental measurements. A satisfactory agreement was obtained when comparing the numerical data to the measurements of dynamic pressure sensors placed in the cylinder head, clearance volume adjustment plugs and suction and discharge nozzles. A comparison with the simulation results of low-order numerical models is also shown to highlight the enhancement in the performance predictability. The matching between experimental and simulated results, together

关键词： Reciprocating compressor CFO 2d modeling Working cycle Porous medium

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The Formation of Gas Bubbles by Processing of Liquid n-Heptane in the Microwave discharge

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PLASMA CHEMISTRY ANd PLASMA PROCESSING 2016年第2期36卷 535-552页

作者： Lebedev, Yu. A. Tatarinov, A. V. Epstein, I. L. Averin, K. A. Russian Acad Sci AV Topchiev Inst Petrochem Synth Leninsky Pr 29 Moscow 119991 Russia

Numerical modeling of the process of formation of gas bubbles during initiation of the microwave discharge in liquid n-heptane at atmospheric pressure has been performed. The developed model has an axial symmetry. The model is based on joint solution of the Maxwell equations, Navier-Stokes equation, heat equation, continuity equations for electrons (written in the ambipolar diffusion approximation) and the n-heptane concentration (including its thermal decomposition and dissociation by electron impact) and the Boltzmann equation for free electrons of the plasma. The calculations allowed to describe the dynamics of the formation of gas bubbles in the liquid, to evaluate the role of electron impact in the decomposition of n-heptane, and to estimate the characteristic times of various processes in the system. The results of new experiments are compared with the simulation results. On the basis of this comparison one could explain the presence in the spectra of the discharge only bands of C-2.

关键词： Microwave discharge discharge in liquid n-Heptane 2d modeling Two-phase fluid

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