Nonlinear Oscillations: Exact Solutions and their Approximations

Kumaraswamy [Generalized probability density-function for double-bounded random-processes, J. Hydrol. 462 (1980), pp. 79–88] introduced a distribution for double-bounded random processes with hydrological applications. For the first time, based on this distribution, we describe a new family of generalized distributions (denoted with the prefix ‘Kw’) to extend the normal, Weibull, gamma, Gumbel, inverse Gaussian distributions, among several well-known distributions. Some special distributions in the new family such as the Kw-normal, Kw-Weibull, Kw-gamma, Kw-Gumbel and Kw-inverse Gaussian distribution are discussed. We express the ordinary moments of any Kw generalized distribution as linear functions of probability weighted moments (PWMs) of the parent distribution. We also obtain the ordinary moments of order statistics as functions of PWMs of the baseline distribution. We use the method of maximum likelihood to fit the distributions in the new class and illustrate the potentiality of the new model with a...

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A new family of generalized distributions

Wind speeds over the world’s oceans have increased over the past two decades, as have wave heights. Studies of climate change typically consider measurements or predictions of temperature over extended periods of time. Climate, however, is much more than temperature. Over the oceans, changes in wind speed and the surface gravity waves generated by such winds play an important role. We used a 23-year database of calibrated and validated satellite altimeter measurements to investigate global changes in oceanic wind speed and wave height over this period. We find a general global trend of increasing values of wind speed and, to a lesser degree, wave height, over this period. The rate of increase is greater for extreme events as compared to the mean condition.

https://researchbank.swinburne.edu.au/file/bca43746-6f16-4ad2-a4b7-27f8d8d60fed/1/PDF (Published version).pdf

Global trends in wind speed and wave height over the past 25 years

Evolution of Design Method Against Random Waves Statistical Properties and Spectral of Sea Waves Transformation and Deformation of Random Sea Waves Design of Breakwaters Design of Coastal Dikes and Seawalls Probabilistic Design of Harbor Facilities Harbor Tranquility and Vessel Mooring Hydraulic Model Tests with Random Waves Theoretical Description of Random Sea Waves Statistical Theory of Irregular Waves Techniques of Random Wave Analysis 2D Computation of Wave Transformation with Random Breaking and Nearshore Currents Statistical Analysis of Extreme Waves Prediction and Control of Beach Deformation Processes.

Random seas and design of maritime structures

The interaction of waves with obstacles is an everyday phenomenon in science and engineering, arising for example in acoustics, electromagnetism, seismology and hydrodynamics. The mathematical theory and technology needed to understand the phenomenon is known as multiple scattering, and this book is the first devoted to the subject. The author covers a variety of techniques, describing first the single-obstacle methods and then extending them to the multiple-obstacle case. A key ingredient in many of these extensions is an appropriate addition theorem: a coherent, thorough exposition of these theorems is given, and computational and numerical issues around them are explored. The application of these methods to different types of problems is also explained; in particular, sound waves, electromagnetic radiation, waves in solids and water waves. A comprehensive bibliography of some 1400 items rounds off the book, which will be an essential reference on the topic for applied mathematicians, physicists and engineers.

Multiple Scattering: Interaction of Time-Harmonic Waves with N Obstacles

Estimation of wave power potential along the Indian coastline

It is believed that Oceans constitute about 70% of the surface of the Earth and about 97% of the water content of the Earth belongs to the oceans. It is believed that about 1% is fresh water, and 2–3% is in the form of glaciers and ice caps. The ocean is rich in natural living and non-living resources. In order to explore and exploit the vast non-living resources like oil, gas and minerals from beneath the ocean floor, a variety of structures are needed to be designed and installed. The perennial instability of shorelines leading to coastal erosion along certain stretches of the coast and the natural coastal hazards like storm surge, tsunami, etc., necessitate protection measures mostly in the form of structures like seawalls, groins, offshore detached breakwaters, etc. constructed along or near the coast. One major developmental activity along the coast is the development of harbors by constructing breakwaters. The major environmental parameters that need to be considered in the design of all the aforementioned different types of structures are the wind, waves, tides and currents. Among these, although the loads due to waves dominate and dictate the design of structures in the marine environment, the characteristics of other parameters are also essential.

Ocean Wave Mechanics: Applications in Marine Structures

Hydrodynamic characteristics of curved and vertical front face pile-supported breakwaters in regular waves

Shoreline movement is a complex phenomenon that is the result of both natural processes and man-made effects. Some of these processes occur over millennia; others are recent and may be cyclic. Understanding changes to the shore requires both a complete understanding of the underlying processes and an ability to accurately measure the changes. This paper presents the one-line shift method of determining datum-based shoreline positions for every month using Arc-GIS and sectional changes using data field measured data with the help of real-time kinematic GPS (RTK-GPS). This result shows the erosion and accretion patches and its volume for the study area.

Vallam Sundar

Papers

Estimation of wave power potential along the Indian coastline

Ocean Wave Mechanics: Applications in Marine Structures

Hydrodynamic characteristics of curved and vertical front face pile-supported breakwaters in regular waves

Shoreline changes along the Northern coast of Chennai port, from field measurements

Comparison between measured and simulated shoreline changes near the tip of Indian peninsula