Download or read book Stochastic Analysis of a Nonlinear Ocean Structural System written by Huan Lin and published by . This book was released on 1994 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stochastic analysis procedures have been recently applied to analyze nonlinear dynamical systems. In this study, nonlinear responses, stochastic and/or chaotic, are examined and interpreted from a probabilistic perspective. A multi-point-moored ocean structural system under regular and irregular wave excitations is analytically examined via a generalized stochastic Melnikov function and Markov process approach. Time domain simulations and associated experimental observations are employed to assist in the interpretation of the analytical predictions. Taking into account the presence of random noise, a generalized stochastic Melnikov function associated with the corresponding averaged system, where a homoclinic connection exists near the primary resonance, is derived. The effects of random noise on the boundary of regions of possible existence of chaotic response is demonstrated via a mean-squared Melnikov criterion. The random wave field is approximated as random perturbations on regular and nearly regular (with very narrow-band spectrum) waves by adding a white noise component, or using a filtered white noise process to fit the JONSWAP spectrum. A Markov process approach is then applied explicitly to analyze the response. The evolution of the probability density function (PDF) of nonlinear stochastic response under the Markov process approach is characterized by a deterministic partial differential equation called the Fokker-Planck equation, which in this study is solved by a path integral solution procedure. Numerical evaluation of the path integral solution is based on path sum, and the short-time propagator is discretized accordingly. Short-time propagation is performed by using a fourth order Runge-Kutta scheme to calculate the most probable (i.e. mean) position in the phase space and to establish the fact that discrete contributions to the random response are locally Gaussian. Transient and steady-state PDF's can be obtained by repeat application of the short-time propagation. Based on depictions of the joint probability density functions and time domain simulations, it is observed that the presence of random noise may expedite the occurrence of "noisy" chaotic response. The noise intensity governs the transition among various types of stochastic nonlinear responses and the relative strengths of coexisting response attractors. Experimental observations confirm the general behavior depicted by the analytical predictions.

Download or read book Stochastically Excited Nonlinear Ocean Structures written by Michael F. Shlesinger and published by World Scientific. This book was released on 1998 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ocean structures, including ships, boats, piers, docks, rigs and platforms, are subject to fair weather wind and waves, as well as violent storms. A scientific analysis of these structures, under varying conditions, requires a mix of civil engineering, physics and applied mathematics. Chapters by experts in these fields are presented which explore the nonlinear responses of ocean structures to stochastic forcing. Theoretical methods calculate aspects of time, frequency and phase space responses. Probabilities governed by stochastic differential equations arc investigated directly or through moment correlations, such as power spectra. Calculations can also involve level crossing statistics and first passage times. Tiffs book will help scientists study stochastic nonlinear equations and help engineers design for short term survivability of structures in storms and long life in the face of everyday fatigue.

Download or read book Stochastic Analysis of the Nonlinear Response Transition Behavior of an Ocean System written by Dongjun Yuk and published by . This book was released on 2001 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: The nonlinear response of an ocean system subjected to random excitations can exhibit very complex dynamic behaviors including jump phenomena and coexistence of attractors. In this study, the stochastic system response behavior of a simple (Duffing) oscillator under narrow-band random excitations is first examined in the subharmonic resonance region. A semi-analytical procedure based on the nonlinear response characteristics of the corresponding deterministic system is developed to derive the response transition probabilities within individual attraction domains and among finite attraction domains under the assumptions of stationarity and Markov process. Overall response amplitude probability distributions are obtained by applying the Bayes formula to the two different types of response transition probability distributions. To validate the prediction capability of the semi-analytical method, numerical simulation of the responses of the Duffing system are generated and statistical characteristics of the response behavior are compared with prediction results. It is shown that the semi-analytical procedure provides more accurate predictions than other approximate methods available in the literature. A parametric study on the effects of variations in excitation intensity and degree of narrow-bandedness is conducted. Results confirmed that the nonlinear response characteristics including jump phenomenon and co-existence of attraction domains are preserved under narrow-band random excitations. The semi-analytical prediction method developed above is then applied to analyze the stochastic response behavior of a nonlinear mooring system subjected to random ocean waves. For modeling of the structural system, a nonlinear structure, nonlinearly-damped (NSND) model is employed and a reverse multiple input/single-output technique is applied to identify the system coefficients. To verify the accuracy and capability of the semi-analytical method in predicting the complex behaviors of the nonlinear mooring system, analytical predictions are compared with experimental results and numerical simulations. System response amplitude probability distributions predicted by the semi-analytical procedure are shown to be in good agreement with experimental and simulation results.

Download or read book Stochastic Dynamics and Reliability of Nonlinear Ocean Systems written by R. A. Ibrahim and published by . This book was released on 1994 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stochastic Dynamics of Marine Structures written by Arvid Naess and published by Cambridge University Press. This book was released on 2013 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: For students and professionals, this covers theory and methods for stochastic modelling and analysis of marine structures under environmental loads.

Download or read book Stochastically Excited Nonlinear Ocean Structures written by Michael F Shlesinger and published by World Scientific. This book was released on 1998-03-26 with total page 337 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ocean structures, including ships, boats, piers, docks, rigs and platforms, are subject to fair weather wind and waves, as well as violent storms. A scientific analysis of these structures, under varying conditions, requires a mix of civil engineering, physics and applied mathematics. Chapters by experts in these fields are presented which explore the nonlinear responses of ocean structures to stochastic forcing. Theoretical methods calculate aspects of time, frequency and phase space responses. Probabilities governed by stochastic differential equations are investigated directly or through moment correlations, such as power spectra. Calculations can also involve level crossing statistics and first passage times. This book will help scientists study stochastic nonlinear equations and help engineers design for short term survivability of structures in storms and long life in the face of everyday fatigue.

Download or read book Stochastic Modelling in Physical Oceanography written by Robert Adler and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 473 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of the ocean is almost as old as the history of mankind itself. When the first seafarers set out in their primitive ships they had to understand, as best they could, tides and currents, eddies and vortices, for lack of understanding often led to loss of live. These primitive oceanographers were, of course, primarily statisticians. They collected what empirical data they could, and passed it down, ini tially by word of mouth, to their descendants. Data collection continued throughout the millenia, and although data bases became larger, more re liable, and better codified, it was not really until surprisingly recently that mankind began to try to understand the physics behind these data, and, shortly afterwards, to attempt to model it. The basic modelling tool of physical oceanography is, today, the partial differential equation. Somehow, we all 'know" that if only we could find the right set of equations, with the right initial and boundary conditions, then we could solve the mysteries of ocean dynamics once and for all.

Download or read book Stochastic Analysis of Structural and Mechanical Vibrations written by Loren D. Lutes and published by . This book was released on 1997 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the aim of stating the fundamental principles and relationships of structural and mechanical vibrations, this guide focuses on the determination of response levels for dynamical systems excited by forces that can be modeled as stochastic processes. It concentrates material in the beginning of the text, with introductions to the fundamentals of stochastic modeling and vibration problems to acquaint students with applications. There are discussions on progressive topics which are the subject of ongoing research, including state-space analysis, nonlinear dynamics, and fatigue damage; the time history implications of bandwidth, with situations varying from narrowband to white noise; time domain integration techniques which provide viable alternatives to the calculus of residues; and an emphasis on time domain interpretations throughout. It includes a number of worked examples to illustrate the modelling of physical problems as well as the proper application of theoretical solutions.

Download or read book A Workshop on New Directions in Extremal Stochastic Analysis of Nonlinear Ocean Systems written by and published by . This book was released on 1993 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stochastic Analysis of Offshore Steel Structures written by Halil Karadeniz and published by Springer Science & Business Media. This book was released on 2012-08-01 with total page 424 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stochastic Analysis of Offshore Steel Structures provides a clear and detailed guide to advanced analysis methods of fixed offshore steel structures using 3D beam finite elements under random wave and earthquake loadings. Advanced and up-to-date research results are coupled with modern analysis methods and essential theoretical information to consider optimal solutions to structural issues. As these methods require and use knowledge of different subject matters, a general introduction to the key areas is provided. This is followed by in-depth explanations supported by design examples, relevant calculations and supplementary material containing related computer programmers. By combining this theoretical and practical approach Stochastic Analysis of Offshore Steel Structures cover a range of key concepts in detail including: The basic principles of standard 3D beam finite elements and special connections, Wave loading - from hydrodynamics to the calculation of wave loading on structural members, Stochastic response calculations with corresponding solution algorithms including earthquakes, and Fatigue damage, reliability calculation and reliability based design optimization. The broad and detailed coverage makes this a solid reference for research oriented studies and practical sophisticated design methods. Students, researchers, insuring bodies and practical designer offices can turn to Stochastic Analysis of Offshore Steel Structures to broaden their theoretical understanding and develop their practical designs and applications of 3D finite analysis in fixed offshore steel structures.

Download or read book Stochastic Dynamics and Control written by Jian-Qiao Sun and published by Elsevier. This book was released on 2006-08-10 with total page 427 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a result of many years of author’s research and teaching on random vibration and control. It was used as lecture notes for a graduate course. It provides a systematic review of theory of probability, stochastic processes, and stochastic calculus. The feedback control is also reviewed in the book. Random vibration analyses of SDOF, MDOF and continuous structural systems are presented in a pedagogical order. The application of the random vibration theory to reliability and fatigue analysis is also discussed. Recent research results on fatigue analysis of non-Gaussian stress processes are also presented. Classical feedback control, active damping, covariance control, optimal control, sliding control of stochastic systems, feedback control of stochastic time-delayed systems, and probability density tracking control are studied. Many control results are new in the literature and included in this book for the first time. The book serves as a reference to the engineers who design and maintain structures subject to harsh random excitations including earthquakes, sea waves, wind gusts, and aerodynamic forces, and would like to reduce the damages of structural systems due to random excitations. · Comprehensive review of probability theory, and stochastic processes· Random vibrations· Structural reliability and fatigue, Non-Gaussian fatigue· Monte Carlo methods· Stochastic calculus and engineering applications· Stochastic feedback controls and optimal controls· Stochastic sliding mode controls· Feedback control of stochastic time-delayed systems· Probability density tracking control

Download or read book Stochastic Climate Models written by Peter Imkeller and published by Springer Science & Business Media. This book was released on 2001 with total page 446 pages. Available in PDF, EPUB and Kindle. Book excerpt: A collection of articles written by mathematicians and physicists, designed to describe the state of the art in climate models with stochastic input. Mathematicians will benefit from a survey of simple models, while physicists will encounter mathematically relevant techniques at work.

Download or read book Chaotic and Random Responses of Ocean Structural Systems written by and published by . This book was released on 1992 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: The long-term goals of the research project were to develop a systematic analysis and design procedure for nonlinear ocean structural systems unifying both the deterministic and stochastic approaches. The procedure would provide a basis for: (1) analyzing the system response to combined periodic and stochastic excitations, (2) estimating the likelihood of chaotic response and developing guidelines for field observations, (3) predicting long-term extreme values of chaotic and stochastic responses based on measured data, and (4) ultimately, developing design methods to take into account both chaotic and stochastic behavior of compliant ocean systems. The near-term goals for the research were first to develop and analyze basic nonlinear ocean system models to understand their deterministic chaotic behavior, and then to extend the basic models to include stochastic aspects. Efforts focused on: (1) developing analytical models of compliant structural systems to understand the physics of chaotic behavior, (2) determining the existence and range of chaotic response of compliant structural systems under combined periodic and stochastic excitations; and (3) validating analytical results experimentally.

Download or read book Extreme Response of Nonlinear Ocean Structures written by Rune Torhaug and published by . This book was released on 1996 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Third Workshop on Reliability of Nonlinear Ocean Structures Under Stochastic Excitation written by and published by . This book was released on 1995 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of the third workshop was to facilitate the advancement of the state of knowledge on the behavior of nonlinear ocean structures under stochastic excitation. The emphasis of the workshop was on the response characteristics of significance for reliability analysis. The workshop would provide a forum for: (1) ONR supported researchers under the program on 'Reliability of Nonlinear Ocean Structures Under Stochastic Excitation' and experienced Navy personnel to hold discussions and exchange ideas on current Naval needs and new research ideas and directions; and (2) the coordination of research efforts among physics, mathematical sciences, and engineering researchers under the program to achieve cross-field synergistic effects.

Download or read book Stochastic Dynamics of Structures written by Jie Li and published by John Wiley & Sons. This book was released on 2009-07-23 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt: In Stochastic Dynamics of Structures, Li and Chen present a unified view of the theory and techniques for stochastic dynamics analysis, prediction of reliability, and system control of structures within the innovative theoretical framework of physical stochastic systems. The authors outline the fundamental concepts of random variables, stochastic process and random field, and orthogonal expansion of random functions. Readers will gain insight into core concepts such as stochastic process models for typical dynamic excitations of structures, stochastic finite element, and random vibration analysis. Li and Chen also cover advanced topics, including the theory of and elaborate numerical methods for probability density evolution analysis of stochastic dynamical systems, reliability-based design, and performance control of structures. Stochastic Dynamics of Structures presents techniques for researchers and graduate students in a wide variety of engineering fields: civil engineering, mechanical engineering, aerospace and aeronautics, marine and offshore engineering, ship engineering, and applied mechanics. Practicing engineers will benefit from the concise review of random vibration theory and the new methods introduced in the later chapters. "The book is a valuable contribution to the continuing development of the field of stochastic structural dynamics, including the recent discoveries and developments by the authors of the probability density evolution method (PDEM) and its applications to the assessment of the dynamic reliability and control of complex structures through the equivalent extreme-value distribution." —A. H-S. Ang, NAE, Hon. Mem. ASCE, Research Professor, University of California, Irvine, USA "The authors have made a concerted effort to present a responsible and even holistic account of modern stochastic dynamics. Beyond the traditional concepts, they also discuss theoretical tools of recent currency such as the Karhunen-Loeve expansion, evolutionary power spectra, etc. The theoretical developments are properly supplemented by examples from earthquake, wind, and ocean engineering. The book is integrated by also comprising several useful appendices, and an exhaustive list of references; it will be an indispensable tool for students, researchers, and practitioners endeavoring in its thematic field." —Pol Spanos, NAE, Ryon Chair in Engineering, Rice University, Houston, USA

Download or read book Stochastic Transport in Upper Ocean Dynamics II written by Bertrand Chapron and published by Springer Nature. This book was released on 2023-11-04 with total page 347 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access proceedings volume brings selected, peer-reviewed contributions presented at the Third Stochastic Transport in Upper Ocean Dynamics (STUOD) 2022 Workshop, held virtually and in person at the Imperial College London, UK, September 26–29, 2022. The STUOD project is supported by an ERC Synergy Grant, and led by Imperial College London, the National Institute for Research in Computer Science and Automatic Control (INRIA) and the French Research Institute for Exploitation of the Sea (IFREMER). The project aims to deliver new capabilities for assessing variability and uncertainty in upper ocean dynamics. It will provide decision makers a means of quantifying the effects of local patterns of sea level rise, heat uptake, carbon storage and change of oxygen content and pH in the ocean. Its multimodal monitoring will enhance the scientific understanding of marine debris transport, tracking of oil spills and accumulation of plastic in the sea. All topics of these proceedings are essential to the scientific foundations of oceanography which has a vital role in climate science. Studies convened in this volume focus on a range of fundamental areas, including: Observations at a high resolution of upper ocean properties such as temperature, salinity, topography, wind, waves and velocity; Large scale numerical simulations; Data-based stochastic equations for upper ocean dynamics that quantify simulation error; Stochastic data assimilation to reduce uncertainty. These fundamental subjects in modern science and technology are urgently required in order to meet the challenges of climate change faced today by human society. This proceedings volume represents a lasting legacy of crucial scientific expertise to help meet this ongoing challenge, for the benefit of academics and professionals in pure and applied mathematics, computational science, data analysis, data assimilation and oceanography.