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3d modeling of transformation of gaseous pollutants in the high-pressure turbine of an aircraft engine

Propulsion and Power Research 2020年第1期9卷 1-14页

作者： Trung Hieu Nguyen Phuong Nguyen-Tri Francois Garnier Department of Mechanical Engineering École de Technologie Supérieure(ETS)MontrealQuebecH3C 1K3Canada Institute of Research and Development Duy Tan UniversityDa Nang550000Viet Nam Department of Chemistry Biochemistry and PhysicsUniversitédu QuébecàTrois-RivièresUniversity of QuebecTrois-Rivières(Québec)G9A 5H7Canada

Aircraft emissions contribute to global climate change and regional air pollution near *** the formation and the transformation of emissions in the aircraft engine is essential to properly quantify the environmental impact and air ***,precise investigation of chemical process in the turbine is challenging because of the complexity of the transformation process in the complex flow relating to the moving blade at high temperature and high *** present here,the first published model study of 3d chemical formations inside a high-pressure turbine and first time to compare three numerical solutions(1d,2d and 3d calculations)of transformation of trace species inside an aircraft *** model has simulated the evolution of principal precursor pollutant gases(NOx and SOx)and other species(hydrogen,oxygen species and carbon oxides).Our results also indicated strong dissimilarities in chemical transformations of 3d *** comparing the three solutions,the results obtained showed that the difference of mole fractions of species can be under predicted by 75%between 1d and 2d calculations and in the comparison of 2d and 3d calculation,the under predicted difference may be 90%.

关键词： Gaseous pollutants High-pressure turbine Aircraft engine 3d modeling

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3d modeling and comparative analysis of the double arcus aorta case

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INTERNATIONAL JOURNAL OF CARdIOVASCULAR IMAGING 2022年第10期38卷 2263-2268页

作者： Avnioglu, Seda dikici, Rumeysa Etli, Mustafa Alanya Alaaddin Keykubat Univ Fac Med Dept Anat Antalya Turkey Alanya Alaaddin Keykubat Univ Fac Med Dept Cardiovasc Surg Antalya Turkey

We analyzed the double arch of a 51-year-old male patient who applied to the outpatient clinic with chest pain and shortness of breath and compared this rare case with the studies in the literature. double aortic arch (dAA) is defined as a type of vascular ring malformation. The incidence of congenital heart diseases is less than 1%. dAA makes up 46-76% of all rings. We aimed to contribute to cardiac surgery by examining and modeling the diameters in the 2d and 3d images of the patient. For 3d modeling, an open-source software program ITK-SNAP 3.8 was used, which converts 2d images from MRI, CT, and ultrasound to 3d medical image volumes. CT images of the case taken from the SECTRA system of our hospital were uploaded to ITK-SNAP and segmentation was performed. With 3d modeling, a better understanding of the stenosis in the trachea and the double arch was achieved. The ascending aorta diameter was 30 mm. There were atherosclerotic changes in the aorta and its branches. The diameter of the right aortic arch was 22.2 mm, and the diameter of the left aortic arch was 14.5 mm. Trachea diameter was found to be 17 mm/13.2 mm. Esophageal diameter was 9.8 mm. The patient had no specific complaints and no medical or surgical treatment was recommended because his physical examination was normal. We think that a better understanding of such cases in 3d may contribute to cardiovascular surgery.

关键词： double aortic arch Variation Congenital vascular malformation ITK-SNAP 3d modeling Imaging

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3d modeling of lion tombstones with UAV photogrammetry: a case study in ancient Phrygia (Turkey)

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ARCHAEOLOGICAL ANd ANTHROPOLOGICAL SCIENCES 2019年第5期11卷 1973-1976页

作者： Toprak, Ahmet Suad Polat, Nizar Uysal, Murat AKU Sch Distance Educ TR-03200 Afyon Turkey AKU Fac Engn Geomat Dept TR-03200 Afyon Turkey

The Phrygian lived in the early seventh century BC and collapsed due to the attacks of nomadic Cimmerians in Anatolia. The Phrygia region which is also called Mountainous Phrygia covers the provinces of Eskisehir, Afyonkarahisar, and Kutahya in Turkey today. Three hundred forty-eight sites and 494 monuments are registered on the national inventory. These monuments are hosting many hundreds of years of knowledge about elder civilizations. The lion tombstone is one of the best protected monuments in Phrygia but it is in a possible danger of exploding by treasure hunters. The preservation of these monuments may not be always possible in physical but today's technologies and methodologies allow us to preserve in digital environment by 3d models. The main advantage of digital documentation is conservation of the natural tissues and shapes of historical monument. This paper reports an application of 3d model generation of the lion tombstone from ancient Phrygia by using photogrammetric techniques.

关键词： Photogrammetry 3d modeling UAV Heritage Lion tombstone Phrygia

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3d modeling OF A COMPLEX BUILdING: FROM MULTI-VIEW IMAGE FUSION TO GOOGLE EARTH PUBLICATION 27

3D MODELING OF A COMPLEX BUILDING: FROM MULTI-VIEW IMAGE FUS...

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27th CIPA International Symposium on documenting the Past for a Better Future

作者： Inzerillo, L. Barone, F. Leto Roberts, R. Univ Palermo Dept Architecture DARCH I-90128 Palermo Italy Univ Pisa Dipartimento Ingn Energia Sistemi Terr & Costruz I-56122 Pisa Italy Univ Palermo Dept Engn DIING I-90128 Palermo Italy

This paper presents a pipeline that aims at illustrating the procedure to realize a 3d model of a complex building integrating the UAV and terrestrial images and modifying the 3d model in order to publish to Google Earth in an interactive modality so as to provide better available models for visualization and use. The main steps of the procedure are the optimization of the UAV flight, the integration of the different UAV and ground floor images and the optimization of the model to be published to GE. The case study has been identified in a building, The Eremo di Santa Rosalia Convent in Sicily which hash more staggered elevations and located in the hills of the hinterland and of which, the online platform only indicate the position on Google Maps (GM) and Go ogle Earth (GE) with a photo from above and a non-urban road whose GM path is not corresponding with the GE photo. The process highlights the integration of the models and showcases a workflow for the publication of the combined 3d model to the GE platform.

关键词： data fusion UAV 3d modeling Google Earth

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Integration of aerial oblique imagery and terrestrial imagery for optimized 3d modeling in urban areas

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ISPRS JOURNAL OF PHOTOGRAMMETRY ANd REMOTE SENSING 2018年 139卷 119-132页

作者： Wu, Bo Xie, Linfu Hu, Han Zhu, Qing Yau, Eric Hong Kong Polytech Univ Dept Land Surveying & Geoinformat Kowloon Hong Kong Peoples R China Wuhan Univ State Key Lab Informat Engn Surveying Mapping & R 129 Luoyu Rd Wuhan Hubei Peoples R China Southwest Jiaotong Univ Fac Geosci & Environm Engn Chengdu Sichuan Peoples R China Ambit Geospatial Solut Ltd Sai Ying Pun Hong Kong Peoples R China

Photorealistic three-dimensional (3d) models are fundamental to the spatial data infrastructure of a digital city, and have numerous potential applications in areas such as urban planning, urban management, urban monitoring, and urban environmental studies. Recent developments in aerial oblique photogrammetry based on aircraft or unmanned aerial vehicles (UAVs) offer promising techniques for 3d modeling. However, 3d models generated from aerial oblique imagery in urban areas with densely distributed highrise buildings may show geometric defects and blurred textures, especially on building facades, due to problems such as occlusion and large camera tilt angles. Meanwhile, mobile mapping systems (MMSs) can capture terrestrial images of close-range objects from a complementary view on the ground at a high level of detail, but do not offer full coverage. The integration of aerial oblique imagery with terrestrial imagery offers promising opportunities to optimize 3d modeling in urban areas. This paper presents a novel method of integrating these two image types through automatic feature matching and combined bundle adjustment between them, and based on the integrated results to optimize the geometry and texture of the 3d models generated from aerial oblique imagery. Experimental analyses were conducted on two datasets of aerial and terrestrial images collected in dortmund, Germany and in Hong Kong. The results indicate that the proposed approach effectively integrates images from the two platforms and thereby improves 3d modeling in urban areas. (C) 2018 International Society for Photogrammetry and Remote Sensing, Inc. (ISPRS). Published by Elsevier B.V. All rights reserved.

关键词： Aerial oblique imagery Terrestrial imagery Photogrammetry 3d modeling

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Technical and functional analysis of Spanish windmills: 3d modeling, computational-fluid-dynamics simulation and finite-element analysis

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ENERGY CONVERSION ANd MANAGEMENT 2016年 123卷 130-139页

作者： Rojas-Sola, Jose Ignacio Benito Bouza-Rodriguez, Jose Menendez-diaz, Agustin Univ Jaen Dept Engn Graph Design & Projects Jaen Spain Univ Vigo Dept Engn Design Vigo Pontevedra Spain Univ Oviedo Dept Construct & Mfg Engn Oviedo Asturias Spain

A detailed study has been made of the two typologies of windmills in Spain, specifically the rectangular-bladed type, represented by the windmill 'Sardinero', located near the town of Campo de Criptana (Ciudad Real province, Spain) and the type with triangular sails (lateens), represented by the windmill 'San Francisco', in the town of Vejer de la Frontera (Cadiz province, Spain). For this, an ad hoc research methodology has been applied on the basis of three aspects: three-dimensional geometric modeling, analysis by computational-fluid dynamics (CFd), and finite-element analysis (FEA). The results found with the CFd technique show the correct functioning of the two windmills in relation to the spatial distribution of the wind velocities and pressures to which each is normally exposed (4-7 m/s in the case of 'Sardinero', and 5-11 for 'San Francisco'), thereby validating the operative functionality of both types. In addition, as a result of the FEA, the spatial distribution of stresses on the rotor has revealed that the greatest concentrations of these occurs in the teeth of the head wheel in 'Sardinero', reaching a value of 12 MPa, and at the base of the masts in the case of the 'San Francisco', with a value of 24 MPa. Also, this analysis evidences that simple, effective designs to reinforce the masts absorb a great concentration of stresses that would otherwise cause breakage. Furthermore, it was confirmed that the oak wood from which the rotors were made functioned properly, as the windmill never exceeded the maximum admissible working stress, demonstrating the effectiveness of the materials used in this period. (C) 2016 Elsevier Ltd. All rights reserved.

关键词： Spanish windmill 3d modeling Computational-fluid dynamics (CFd) Simulation Finite-element analysis (FEA) Industrial archaeology Cultural heritage

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development of a 3d modeling algorithm for tunnel deformation monitoring based on terrestrial laser scanning

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Underground Space 2017年第1期2卷 16-29页

作者： Xiongyao Xie Xiaozhi Lu Key Laboratory of Geotechnical and Underground Engineering Tongji UniversityShanghaiChina Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghaiChina Guangzhou Metro Design&Research Institute Co.Ltd. GuangdongChina

deformation monitoring is vital for tunnel *** monitoring techniques measure only a few data points,which is insufficient to understand the deformation of the entire *** Laser Scanning(TLS)is a newly developed technique that can collect thousands of data points in a few minutes,with promising applications to tunnel deformation *** raw point cloud collected from TLS cannot display tunnel deformation;therefore,a new 3d modeling algorithm was developed for this *** 3d modeling algorithm includes modules for preprocessing the point cloud,extracting the tunnel axis,performing coordinate transformations,performing noise reduction and generating the 3d *** results from TLS were compared to the results of total station and numerical simulation,confirming the reliability of TLS for tunnel deformation ***,a case study of the Shanghai West Changjiang Road tunnel is introduced,where TLS was applied to measure shield tunnel deformation over multiple ***,segment dislocation and cross section convergence were measured and visualized using the proposed 3d modeling algorithm.

关键词： Terrestrial laser scanning Tunnel deformation monitoring Point cloud 3d modeling

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Stabilizing 3d modeling with geometric constraints propagation

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COMPUTER VISION ANd IMAGE UNdERSTANdING 2009年第11期113卷 1147-1157页

作者： Farenzena, Michela Fusiello, Andrea Univ Verona Dipartimento Informat I-37134 Verona Italy

This paper proposes a technique for estimating piecewise planar models of objects from their images and geometric constraints. First, assuming a bounded noise in the localization of 2d points, the position of the 3d point is estimated as a polyhedron containing all the possible solutions of the triangulation. Then, given the topological structure of the 3d points cloud, geometric relationships among facets, such as coplanarity, parallelism, orthogonality, and angle equality, are automatically detected. A subset of them that is sufficient to stabilize the 3d model estimation is selected with a flow-network based algorithm. Finally, a feasible instance of the 3d model, i.e. one that satisfies the geometric constraints and whose 3d vertices lie within the associated polyhedral bounds, is computed by solving a Constraint Satisfaction Problem. The process accommodates uncertainty in a non-probabilistic fashion and thus provides rigorous results. Synthetic and real experiments illustrate the approach. (C) 2009 Elsevier Inc. All rights reserved,

关键词： 3d modeling Geometric constraints

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Reality3dSketch: Rapid 3d modeling of Objects From Single Freehand Sketches

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IEEE TRANSACTIONS ON MULTIMEdIA 2024年 26卷 4859-4870页

作者： Chen, Tianrun ding, Chaotao Zhu, Lanyun Zang, Ying Liao, Yiyi Li, Zejian Sun, Lingyun Zhejiang Univ Coll Comp Sci & Technol Hangzhou 310027 Peoples R China Huzhou Univ Sch Informat & Engn Huzhou 313000 Peoples R China Singapore Univ Technol & Design Informat Syst Technol & Design Pillar Singapore 487372 Singapore Zhejiang Univ Coll Informat Sci & Elect Engn Hangzhou 310027 Peoples R China Zhejiang Univ Sch Software Technol Hangzhou 310027 Peoples R China

The emerging trend of AR/VR places great demands on 3d content. However, most existing software requires expertise and is difficult for novice users to use. In this paper, we aim to create sketch-based modeling tools for user-friendly 3d modeling. We introduce Reality3dSketch with a novel application of an immersive 3d modeling experience, in which a user can capture the surrounding scene using a monocular RGB camera and can draw a single sketch of an object in the real-time reconstructed 3d scene. A 3d object is generated and placed in the desired location, enabled by our novel neural network with the input of a single sketch. Our neural network can predict the pose of a drawing and can turn a single sketch into a 3d model with view and structural awareness, which addresses the challenge of sparse sketch input and view ambiguity. We conducted extensive experiments synthetic and real-world datasets and achieved state-of-the-art (SOTA) results in both sketch view estimation and 3d modeling performance. According to our user study, our method of performing 3d modeling in a scene is >5x faster than conventional methods. Users are also more satisfied with the generated 3d model than the results of existing methods.

关键词： Three-dimensional displays Solid modeling Image reconstruction Software Shape Estimation Context modeling 3d modeling 3d reconstruction computer/ human interaction sketch

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3d modeling by Scanning Physical Modifications 28

3D Modeling by Scanning Physical Modifications

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28th SIBGRAPI Conference on Graphics, Patterns and Images SIBGRAPI

作者： Hattab, Ammar Taubin, Gabriel Brown Univ Sch Engn Providence RI 02912 USA

ISBN: (纸本)9781467379625

3d shape design tends to be a long and tedious process, with the design of a detailed 3d part usually requiring multiple revisions. Fabricating physical prototypes using low cost 3d fabrication technologies at intermediate stages of the design process is now a common practice, which helps the designer discover errors, and to incrementally refine the design. Most often, implementing the required changes directly in the computer model, within the 3d modeling software, is more difficult and time consuming than modifying the physical model directly using hand cutting, caving and sculpting tools, power tools, or machine tools. When one of the two models is modified, the changes need to be transferred to the other model, a process we refer to as synchronization. Changes made to the computer model can be transferred to the physical model by 3d printing a new physical model. In this paper, we address the problem of synchronizing the computer model to changes made in the physical model by 3d scanning the modified physical model, automatically detecting the changes, and updating the computer model. The proposed process comprises algorithms to: 1) register each 3d scan with a previous 3d scan and/or with the 3d representation used by the 3d modeling software;2) detect the changes (subtractive and/or additive);and 3) perform the changes on the 3d computer model.

关键词： 3d registration 3d reverse engineering 3d modeling tangible interface human-computer interaction

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