Download or read book Probabilistic Bayesian Approaches to Model the Global Vibro acoustic Performance of Vehicles written by Gianluigi Brogna and published by . This book was released on 2019 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the automotive domain, although already quite elaborate, the current approaches to predict and analyse the vibro-acoustic behaviour of a vehicle are still far from the complexity of the real system. Among other limitations, design specifications are still essentially based on extreme loading conditions, useful when verifying the mechanical strength, but not representative of the actual vehicle usage, which is instead important when addressing the vibro-acoustic performance. As a consequence, one main aim here is to build a prediction model able to take into account the loading scenarios representative of the actual vehicle usage, as well as the car structural uncertainty (due, for instance, to production dispersion). The proposed model shall cover the low and mid-frequency domain. To this aim, four main steps are proposed in this work: (1) the definition of a model for a general vehicle system, pertinent to the vibro-acoustic responses of interest; (2) the estimation of the whole set of loads applied to this system in a large range of operating conditions; (3) the statistical analysis and modelling of these loads as a function of the vehicle operating conditions; (4) the analysis of the application of the modelled loads to non-parametric stochastic transfer functions, representative of the vehicle structural uncertainty. To achieve the previous steps, ad hoc Bayesian algorithms have been developed and applied to a large industrial database. The Bayesian framework is considered here particularly valuable since it allows taking into account prior knowledge, namely from automotive experts, and since it easily enables uncertainty propagation between the layers of the probabilistic model. Finally, this work shows that the proposed algorithms, more than simply yielding a model of the vibro-acoustic response of a vehicle, are also useful to gain deep insights on the dominant physical mechanisms at the origin of the response of interest.
Download or read book Stochastic Multilevel Reduced order Computational Model in Vibroacoustics Applied to Automobiles written by Justin Reyes and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis deals with the vibroacoustics of complex systems over a broad frequency band of analysis and has been made as part of the vibroacoustics of automobiles. The system under consideration is composed of a complex structure coupled with an internal acoustic cavity. The complex structure is defined by a complex geometry, constituted of heterogeneous materials and of two types of structural levels: a stiff main part and numerous flexible sub-parts. In such a structure, the vibroacoustics model is represented by the usual global-displacements elastic modes associated with the main part, and by numerous local elastic modes, which correspond to the preponderant vibrations of the flexible sub-parts. However, in the framework of automobile vibroacoustic modeling, the main difficulty is the interweaving of the global displacements with the numerous local displacements, which introduce an overlap of the usual three frequency domains (low- (LF), medium- (MF), and high frequency (HF)). In the automotive industry, computational vibroacoustic models are used for predicting the internal noise levels due to structural excitations. However, the dimension of computational vibroacoustic models is very high. In this work, the computational model has 19 million of degrees-of-freedom (DOFs) for the structural part and 1 million of DOFs for the coupled acoustic cavity. Such a high dimension brings some computational challenges that are mostly overpassed by introducing a reduced-order computational model (ROM) constructed with a classical modal analysis. Nevertheless, the dimension of such ROM is still very important when the frequency band of analysis overlaps the LF, MF and HF domains. Consequently, a multi-level reduced-order model - for the structure is constructed over the LF, MF, and HF frequency bands. The strategy is based on a multi-level projection consisting in introducing three reduced-order bases (ROBs) that are obtained by using a spatial filtering methodology of local displacements. The filtering method requires the introduction of a set of global shape functions that define a subspace for projecting the mass matrix of the structure yielding a matrix for which the null space is made up of local displacements that need to be filtered out. In addition, a classical ROM using acoustic modes is carried out for the acoustic cavity. Then, the coupling between the multi-level reduced order model and the acoustic reduced-order model is presented. The nonparametric probabilistic modeling is then proposed in order to take into account the model uncertainties induced by modeling errors, errors whose effects increase with frequency.This novel stochastic multilevel ROM allows for adapting the level of uncertainties of the structure to each part of the broad frequency band, that is to the LF, MF, and HF sub-bands. One of the great difficulties of this work has been to develop a methodology and algorithms, which make it possible to analyze very large vibroacoustic computational models with computing times (CPU) which remain relatively low and which, moreover, do not lead to memory (RAM) problems requiring the use of external hard disks, which would make it impossible to use the developed method. The application presented consists of a very large digital vibroacoustic model of a car (structure coupled to an internal acoustic cavity). The numerical results obtained are those which were hoped for concerning their qualities and the feasibility of the calculations.
Download or read book Statistical Vibro acoustic Modelling of Nonlinear Systems with Applications in Vehicles written by Luis Andrade Acosta and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Shock and Vibration Digest written by and published by . This book was released on 2000 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bayesian Methods for Structural Dynamics and Civil Engineering written by Ka-Veng Yuen and published by John Wiley & Sons. This book was released on 2010-02-22 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bayesian methods are a powerful tool in many areas of science and engineering, especially statistical physics, medical sciences, electrical engineering, and information sciences. They are also ideal for civil engineering applications, given the numerous types of modeling and parametric uncertainty in civil engineering problems. For example, earthquake ground motion cannot be predetermined at the structural design stage. Complete wind pressure profiles are difficult to measure under operating conditions. Material properties can be difficult to determine to a very precise level – especially concrete, rock, and soil. For air quality prediction, it is difficult to measure the hourly/daily pollutants generated by cars and factories within the area of concern. It is also difficult to obtain the updated air quality information of the surrounding cities. Furthermore, the meteorological conditions of the day for prediction are also uncertain. These are just some of the civil engineering examples to which Bayesian probabilistic methods are applicable. Familiarizes readers with the latest developments in the field Includes identification problems for both dynamic and static systems Addresses challenging civil engineering problems such as modal/model updating Presents methods applicable to mechanical and aerospace engineering Gives engineers and engineering students a concrete sense of implementation Covers real-world case studies in civil engineering and beyond, such as: structural health monitoring seismic attenuation finite-element model updating hydraulic jump artificial neural network for damage detection air quality prediction Includes other insightful daily-life examples Companion website with MATLAB code downloads for independent practice Written by a leading expert in the use of Bayesian methods for civil engineering problems This book is ideal for researchers and graduate students in civil and mechanical engineering or applied probability and statistics. Practicing engineers interested in the application of statistical methods to solve engineering problems will also find this to be a valuable text. MATLAB code and lecture materials for instructors available at http://www.wiley.com/go/yuen
Download or read book Leveraging Artificial Intelligence in Engineering Management and Safety of Infrastructure written by M.Z. Naser and published by CRC Press. This book was released on 2022-11-17 with total page 459 pages. Available in PDF, EPUB and Kindle. Book excerpt: The design, construction, and upkeep of infrastructure is comprised of a multitude of dimensions spanning a highly complex paradigm of interconnected opportunities and challenges. While traditional methods fall short of adequately accounting for such complexity, artificial intelligence (AI) presents novel and out-of-the-box solutions that effectively tackle the growing demands of our infrastructure. The convergence between AI and civil engineering is an emerging frontier with tremendous potential. The book is likely to provide a boost to the state of infrastructure engineering by fostering a new look at civil engineering that capitalizes on AI as its main driver. It highlights the ongoing push to adopt and leverage AI to realize contemporary, intelligent, safe, and resilient infrastructure. The book comprises interdisciplinary and novel works from across the globe. It presents findings from innovative efforts supplemented with physical tests, numerical simulations, and case studies – all of which can be used as benchmarks to carry out future experiments and/or facilitate the development of future AI models in structural engineering, traffic engineering, construction engineering, and construction materials. The book will serve as a guide for a wide range of audiences, including senior undergraduate and graduate students, professionals, and government officials of civil, traffic, and computer engineering backgrounds, as well as for those engaged in urban planning and human sciences.
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 934 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Diagnostics and Prognostics of Engineering Systems Methods and Techniques written by Kadry, Seifedine and published by IGI Global. This book was released on 2012-09-30 with total page 461 pages. Available in PDF, EPUB and Kindle. Book excerpt: Industrial Prognostics predicts an industrial systems lifespan using probability measurements to determine the way a machine operates. Prognostics are essential in determining being able to predict and stop failures before they occur. Therefore the development of dependable prognostic procedures for engineering systems is important to increase the systems performance and reliability. Diagnostics and Prognostics of Engineering Systems: Methods and Techniques provides widespread coverage and discussions on the methods and techniques of diagnosis and prognosis systems. Including practical examples to display the methods effectiveness in real-world applications as well as the latest trends and research, this reference source aims to introduce fundamental theory and practice for system diagnosis and prognosis.
Download or read book Deep Learning Applications Volume 2 written by M. Arif Wani and published by Springer. This book was released on 2020-12-14 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents selected papers from the 18th IEEE International Conference on Machine Learning and Applications (IEEE ICMLA 2019). It focuses on deep learning networks and their application in domains such as healthcare, security and threat detection, fault diagnosis and accident analysis, and robotic control in industrial environments, and highlights novel ways of using deep neural networks to solve real-world problems. Also offering insights into deep learning architectures and algorithms, it is an essential reference guide for academic researchers, professionals, software engineers in industry, and innovative product developers.
Download or read book Handbook Of Machine Learning Volume 2 Optimization And Decision Making written by Tshilidzi Marwala and published by World Scientific. This book was released on 2019-11-21 with total page 321 pages. Available in PDF, EPUB and Kindle. Book excerpt: Building on , this volume on Optimization and Decision Making covers a range of algorithms and their applications. Like the first volume, it provides a starting point for machine learning enthusiasts as a comprehensive guide on classical optimization methods. It also provides an in-depth overview on how artificial intelligence can be used to define, disprove or validate economic modeling and decision making concepts.
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2002 with total page 896 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electrical Electronics Abstracts written by and published by . This book was released on 1997 with total page 1860 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 994 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Probability written by Tamás Rudas and published by SAGE. This book was released on 2008-02-21 with total page 489 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This is a valuable reference guide for readers interested in gaining a basic understanding of probability theory or its applications in problem solving in the other disciplines." —CHOICE Providing cutting-edge perspectives and real-world insights into the greater utility of probability and its applications, the Handbook of Probability offers an equal balance of theory and direct applications in a non-technical, yet comprehensive, format. Editor Tamás Rudas and the internationally-known contributors present the material in a manner so that researchers of various backgrounds can use the reference either as a primer for understanding basic probability theory or as a more advanced research tool for specific projects requiring a deeper understanding. The wide-ranging applications of probability presented make it useful for scholars who need to make interdisciplinary connections in their work. Key Features Contains contributions from the international who's-who of probability across several disciplines Offers an equal balance of theory and applications Explains the most important concepts of probability theory in a non-technical yet comprehensive way Provides in-depth examples of recent applications in the social and behavioral sciences as well as education, business, and law Intended Audience This Handbook makes an ideal library purchase. In addition, this volume should also be of interest to individual scholars in the social and behavioral sciences.
Download or read book Applied mechanics reviews written by and published by . This book was released on 1948 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Abstract Journal in Earthquake Engineering written by and published by . This book was released on 1996 with total page 616 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Annual Index written by and published by . This book was released on 1986 with total page 1336 pages. Available in PDF, EPUB and Kindle. Book excerpt:
