Дисертації з теми "3d nonlinear models"
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся з топ-16 дисертацій для дослідження на тему "3d nonlinear models".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Переглядайте дисертації для різних дисциплін та оформлюйте правильно вашу бібліографію.
Reichert, Thomas. "Development of 3D lattice models for predicting nonlinear timber joint behaviour." Thesis, Edinburgh Napier University, 2009. http://researchrepository.napier.ac.uk/Output/2827.
Повний текст джерелаMARZIANI, ROBERTA. "Asymptotic analysis of nonlinear models for line defects in materials." Doctoral thesis, Gran Sasso Science Institute, 2020. http://hdl.handle.net/20.500.12571/10041.
Повний текст джерелаCitipitioglu, Ahmet Muhtar. "Development and assessment of response and strength models for bolted steel connections using refined nonlinear 3D finite element analysis." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31691.
Повний текст джерелаCommittee Chair: Haj-Ali, Rami; Committee Co-Chair: Leon, Roberto; Committee Co-Chair: White, Donald; Committee Member: DesRoches, Reginald; Committee Member: Gentry, Russell. Part of the SMARTech Electronic Thesis and Dissertation Collection.
Lorenz, Haik. "Texturierung und Visualisierung virtueller 3D-Stadtmodelle." Phd thesis, Universität Potsdam, 2011. http://opus.kobv.de/ubp/volltexte/2011/5387/.
Повний текст джерелаThis thesis concentrates on virtual 3D city models that digitally encode objects, phenomena, and processes in urban environments. Such models have become core elements of geographic information systems and constitute a major component of geovirtual 3D worlds. Expert users make use of virtual 3D city models in various application domains, such as urban planning, radio-network planning, and noise immision simulation. Regular users utilize virtual 3D city models in domains, such as tourism, and entertainment. They intuitively explore photorealistic virtual 3D city models through mainstream applications such as GoogleEarth, which additionally enable users to extend virtual 3D city models by custom 3D models and supplemental information. Creation and rendering of virtual 3D city models comprise a large number of processes, from which texturing and visualization are in the focus of this thesis. In the area of texturing, this thesis presents concepts and techniques for automatic derivation of photo textures from georeferenced oblique aerial imagery and a concept for the integration of surface-bound data into virtual 3D city model datasets. In the area of visualization, this thesis presents concepts and techniques for multiperspective views and for high-quality rendering of nonlinearly projected virtual 3D city models in interactive systems. The automatic derivation of photo textures from georeferenced oblique aerial imagery is a refinement process for a given virtual 3D city model. Our approach uses oblique aerial imagery, since it provides a citywide highly redundant coverage of surfaces, particularly building facades. From this imagery, our approach extracts all views of a given surface and creates a photo texture by selecting the best view on a pixel level. By processing all surfaces, the virtual 3D city model becomes completely textured. This approach has been tested for the official 3D city model of Berlin and the model of the inner city of Munich accessible in GoogleEarth. The integration of surface-bound data, which include textures, into virtual 3D city model datasets has been performed in the context of CityGML, an international standard for the exchange and storage of virtual 3D city models. We derive a data model from a set of use cases and integrate it into the CityGML standard. The data model uses well-known concepts from computer graphics for data representation. Interactive multiperspective views of virtual 3D city models seamlessly supplement a regular perspective view with a second perspective. Such a construction is inspired by panorama maps by H. C. Berann and aims at increasing the amount of information in the image. Key aspect is the construction's use in an interactive system. This thesis presents an approach to create multiperspective views on 3D graphics hardware and exemplifies the extension of bird's eye and pedestrian views. High-quality rendering of nonlinearly projected virtual 3D city models focuses on the implementation of nonlinear projections on 3D graphics hardware. The developed concepts and techniques focus on high image quality. This thesis presents two such concepts, namely dynamic mesh refinement and piecewise perspective projections, which both enable the use of all graphics hardware features, such as screen space gradients and anisotropic texture filtering under nonlinear projections. Both concepts are generic and customizable towards specific projections. They enable the use of common computer graphics effects, such as stylization effects or procedural textures, for nonlinear projections at optimal image quality and interactive frame rates. This thesis comprises essential techniques for virtual 3D city model processing. First, the results of this thesis enable automated creation of textures for and their integration as individual attributes into virtual 3D city models. Hence, this thesis contributes to an improved creation and continuation of textured virtual 3D city models. Furthermore, the results provide novel approaches to and technical solutions for projecting virtual 3D city models in interactive visualizations. Such nonlinear projections are key components of novel user interfaces and interaction techniques for virtual 3D city models, particularly on mobile devices and in immersive environments.
Hong, Jung-Pyo. "Three-dimensional nonlinear finite element model for single and multiple dowel-type wood connections." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/364.
Повний текст джерелаCarloni, Federico. "A 3D model based on the SAM Method for seismic studies of masonry buildings." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/17151/.
Повний текст джерелаXia, Liang. "Towards optimal design of multiscale nonlinear structures : reduced-order modeling approaches." Thesis, Compiègne, 2015. http://www.theses.fr/2015COMP2230/document.
Повний текст джерелаHigh-performance heterogeneous materials have been increasingly used nowadays for their advantageous overall characteristics resulting in superior structural mechanical performance. The pronounced heterogeneities of materials have significant impact on the structural behavior that one needs to account for both material microscopic heterogeneities and constituent behaviors to achieve reliable structural designs. Meanwhile, the fast progress of material science and the latest development of 3D printing techniques make it possible to generate more innovative, lightweight, and structurally efficient designs through controlling the composition and the microstructure of material at the microscopic scale. In this thesis, we have made first attempts towards topology optimization design of multiscale nonlinear structures, including design of highly heterogeneous structures, material microstructural design, and simultaneous design of structure and materials. We have primarily developed a multiscale design framework, constituted of two key ingredients : multiscale modeling for structural performance simulation and topology optimization forstructural design. With regard to the first ingredient, we employ the first-order computational homogenization method FE2 to bridge structural and material scales. With regard to the second ingredient, we apply the method Bi-directional Evolutionary Structural Optimization (BESO) to perform topology optimization. In contrast to the conventional nonlinear design of homogeneous structures, this design framework provides an automatic design tool for nonlinear highly heterogeneous structures of which the underlying material model is governed directly by the realistic microstructural geometry and the microscopic constitutive laws. Note that the FE2 method is extremely expensive in terms of computing time and storage requirement. The dilemma of heavy computational burden is even more pronounced when it comes to topology optimization : not only is it required to solve the time-consuming multiscale problem once, but for many different realizations of the structural topology. Meanwhile we note that the optimization process requires multiple design loops involving similar or even repeated computations at the microscopic scale. For these reasons, we introduce to the design framework a third ingredient : reduced-order modeling (ROM). We develop an adaptive surrogate model using snapshot Proper Orthogonal Decomposition (POD) and Diffuse Approximation to substitute the microscopic solutions. The surrogate model is initially built by the first design iteration and updated adaptively in the subsequent design iterations. This surrogate model has shown promising performance in terms of reducing computing cost and modeling accuracy when applied to the design framework for nonlinear elastic cases. As for more severe material nonlinearity, we employ directly an established method potential based Reduced Basis Model Order Reduction (pRBMOR). The key idea of pRBMOR is to approximate the internal variables of the dissipative material by a precomputed reduced basis computed from snapshot POD. To drastically accelerate the computing procedure, pRBMOR has been implemented by parallelization on modern Graphics Processing Units (GPUs). The implementation of pRBMOR with GPU acceleration enables us to realize the design of multiscale elastoviscoplastic structures using the previously developed design framework inrealistic computing time and with affordable memory requirement. We have so far assumed a fixed material microstructure at the microscopic scale. The remaining part of the thesis is dedicated to simultaneous design of both macroscopic structure and microscopic materials. By the previously established multiscale design framework, we have topology variables and volume constraints defined at both scales
Wei, Sicong. "A 3D Sliding Bearing Finite Element Based on The Bouc-Wen Hysteretic Model : Mathematical modelling and numerical implementation." Thesis, KTH, Bro- och stålbyggnad, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-289480.
Повний текст джерелаGuney, Murat Efe. "A Numerical Procedure For The Nonlinear Analysis Of Reinforced Concrete Frames With Infill Walls." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606318/index.pdf.
Повний текст джерелаGAZZANI, VALENTINA. "Influence of FE Modelling on Typical and Specific Vulnerabilities of RC School Buildings." Doctoral thesis, Università Politecnica delle Marche, 2019. http://hdl.handle.net/11566/263653.
Повний текст джерелаThe vulnerability assessment of existing school buildings against earthquakes represents a priority concern for the society in seismic countries. Since structures belonging to the same type and construction period may share similar features, it was possible to point out typical and specific seismic vulnerabilities related to different school architectural layouts for buildings that host the lower levels of the Italian education system. Firstly, to estimate the performance of buildings in a fast way, the vulnerability of each school building belonging to the municipality of Trecastelli was assessed, adopting a lumped plasticity approach and a nonlinear static procedure. With the aim of quantifying the effective influence of these vulnerabilities detected on the global seismic behaviour, a RC school building was chosen and three different models were implemented correspond to as many different approaches affected by various limitations in the representativeness respect to the reality. The different modelling technique used follow the lumped plasticity, the distributed plasticity (fibre model) and the 3D Continuum FE approaches. Nonlinear static (pushover) analyses were performed to assess the global seismic behaviour of the structure. The comparison of the numerical results has shown that the fibre model is the least suitable mean to represent the shear problems of the case study. Instead, the lumped plasticity model is closer to reality than the previous one but not precise enough to consider the concomitance of bending, shear and axial force and the interaction between them in the inelastic response. Of course, the 3D Continuum model is much more accurate than other models to describe the mechanisms developed in the joint panels which are very complex and combined. Finally, the effectiveness of a possible CFRP local strengthening intervention for the case study limited to confine the unconfined beam-column joints was also considered.
Daněk, Michal. "Simulace toroidních cívek v Ansoft Maxwell 3D." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-218197.
Повний текст джерелаBayhan, Beyhan. "Buildings Under Recurring Near-field Earthquakes." Phd thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612424/index.pdf.
Повний текст джерелаzce earthquake in Bolu and May 1st 2003 Bingö
l earthquake in Bingö
l, respectively. The ground motion sensor stations were fortuitously nearby in an adjacent single-story building in Bolu and Bingö
l. The station in Erzincan was in a single-story building about 2 km away from the case study building but we assume that the record applies to the building there. These three data represent characteristics of near-field ground motions and the distance of the sensor stations to the nearest fault trace was less than 10 km. The buildings sustained varying degrees of damage during the earthquakes and their damage survey was employed through site investigations. Given that the damage information, input motions, design drawings and material properties of the buildings are all known, this provided an opportunity to predict the structural damage to these buildings by proper modeling using the tools of current computational performance assessment procedures. In this circumstance, three dimensional (3D) analytical models of the MPWR buildings have been performed. Bi-directional excitations have been applied to the models by nonlinear time history analyses (NTHA). The results illustrate that NTHA are capable of indicating the occurrence of shear failure in captive columns
however, they overestimate the global damage level for all buildings. The overestimation is more significant in Erzincan case where the building sustained a pulse-type motion without significant distress.
Deserranno, Dimitri. "A Multi-Scale Finite Element Model of the Cardiac Ventricles." Case Western Reserve University School of Graduate Studies / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=case1148984314.
Повний текст джерелаWang, Yunli. "Etude expérimentale et numérique des oscillations hydrodynamiques en milieux poreux partiellement saturés." Thesis, Toulouse, INPT, 2010. http://www.theses.fr/2010INPT0127/document.
Повний текст джерелаThis thesis aims at investigating experimentally, analytically and numerically, the consequences of hydrodynamic variations and oscillations with high temporal variability in partially saturated porous media. The problems investigated in this work involve “free surfaces” both outside and inside the porous media, the free surface being defined as the “atmospheric” water pressure isosurface (Pwater = Patm). The laboratory experiments studied in this work are, respectively: Lateral imbibition in a dry sand box with significant capillary effects; Transmission of oscillations of the free surface through a vertical sand box placed in a small wave canal (IMFT, Toulouse); Dynamics of free surface oscillations and wave propagation in a large wave canal (HYDRALAB, Barcelona), partially covered with sand, with measurements of both open water and groundwater levels, and of sand topography (erosion / deposition). For theoretical studies, we have developed linearized analytical solutions. Here is a sample problem that was treated analytically in this work: The linearized equation of Dupuit-Boussinesq (DB) for transient free surface flow, assuming horizontal flow and instantaneous wetting/drainage of the unsaturated zone: forced oscillations, wave transmission and dissipation through a rectangular sandbox. We also developed a weakly nonlinear solution of the Dupuit-Boussinesq equation to study the sudden imbibition (temporal monitoring of the wetting front). We have studied the different types of transient flow problems related to the experiments cited above by numerical simulation. In particular, we have simulated unsaturated or partially saturated transient flows in vertical cross-section, using a computer code (BIGFLOW 3D) which solves a generalized version of Richards’ equation. Thus, using the Richards / BIGFLOW 3D model, we have studied numerically the experiment of unsaturated imbibition in a dry sand (IMFT sandbox), and then, with the same model, we have also studied the partially saturated wave propagation experiment in the large Barcelona wave canal (HYDRALAB laboratory), focusing on the sloping sandy beach, with coupling between the micro-porous zone (sand) and the “macro-porous” zone (open water). To interpret the results of the latter experiment and compare them to simulations, we use several methods of signal analyzis and signal processing, such as: Fourier analysis, discrete multi-resolution wavelets (Daubechies), auto and cross-correlation functions. These methods are combined with pre-filtering methods to estimate trends and residuals (moving averages; discrete wavelet analyses). This signal analyzis has allowed us to interpret and quantify water propagation phenomena through a sandy beach. To sum up, different modeling approaches, combined with model calibration procedures, were applied to transient nonlinear coupled flow problems. These approaches have allowed us to reproduce globally the water content distributions and water level propagation in the different configurations studied in this work
Huang, Po-yuan, and 黃柏元. "Biomechanical Study of Different Fixation Techniques for Unstable Pelvic Fractures Using 3D Nonlinear Finite Element Models of Spine-Pelvis-Femur Complex and Biomechanical Experiments." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/76695185435870831420.
Повний текст джерела國立臺灣科技大學
應用科技研究所
103
Unstable pelvic fracture represents a severe injury associated with high morbidity and mortality. In the past, several types of fixators were used to treat this unstable fracture, including external fixators, plates, sacral bars, iliosacral screws, and pre-tensed curved bar. However, the biomechanical performances of the above fixation techniques were mainly evaluated according to the outcomes of clinical applications, and only one of the fixation techniques was selected and evaluated. To our knowledge, there were few studies to analyze and compare the biomechanical performances of different pelvic fixation techniques. In addition, the past studies had investigated one of the fixation techniques by using finite element methods. However, there has been no study that investigated the biomechanical performances of the fixation techniques by using 3D nonlinear finite element models of spine-pelvis-femur complex. Thus, the purpose of this study was to analyze and investigate the biomechanical performances of different pelvic fixation techniques for the treatment of unstable pelvic fracture. Three-dimensional nonlinear finite element models of spine-pelvis-femur complex were developed to investigate the biomechanical performances of different pelvic fixation techniques by using ANSYS Workbench 14.5. Concurrently, the biomechanical experiment was developed to validate the numerical results. In this study, three types of the pelvic fixators were evaluated and discussed, including posterior iliosacral screws, sacral bars, and locking compression plate. The fixation stability, pelvic stress, and implant strength were obtained and used to evaluate the strength and limitation of each fixation technique. The results of this study showed that the posterior iliosacral screws had better fixation stability compared with the sacral bars and the locking compression plate. Additionally, the locking compression plate revealed higher stress concentration effects on the pelvis and the implants compared with others. We hope that the outcomes of this study could directly provide the surgical suggestion to orthopedic surgeons and help them to understand the biomechanics of different pelvic fixation techniques.
Wang, Wei-Yi, and 王瑋毅. "CAD Model-based 3D Object Pose Estimation using a Nonlinear Contour Fitting Algorithm." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/37070880864058569809.
Повний текст джерела淡江大學
電機工程學系碩士班
103
This thesis presents a three-dimensional (3D) model building method and a model-based visual tracking method for an object-of-interest. The proposed methods can help robots to accomplish more difficult tasks, such as 3D pose estimation and robust visual tracking of a rigid object. The contents of this thesis are divided into two parts. The first part presents the design of a 3D computer-aided design (CAD) model building algorithm, which produces a 3D CAD model of a geometrical object to facilitate the subsequent visual tracking task. The second part presents the design of a CAD-model based object pose estimation algorithm to implement the function of robust 3D object tracking. We first used Microsoft Kinect to capture the point cloud data of an object-of-interest for extracting its planar features. Then, its 3D CAD model was produced by vertex information of the object found by using geometrical characteristics of the object planar features. Next, a robust CAD-model based visual tracking method was implemented by fitting the contour of the projection of the 3D CAD model to the object contour on the image plane, which also can provide 3D pose information of the object during the visual tracking task.