Algorithms for Automatic, Real-Time Tsunami Detection in Sea Level Measurements

Automatic, real-time tsunami detection in sea-level measurements is a main component of a tsunami early warning system (TEWS). Although a great effort has been recently undertaken by the scientific and engineering community in developing new technologies (e.g. satellite altimetry, detectors of low-frequency elastic oscillations associated to a tsunami) capable of increasing the awareness of potential tsunamis in the minimum amount of time, at present direct detection in sea level measurements is still the main mean to confirm their actual generation and propagation, i.e. to upgrade or cancel the rapid initial warning usually given on the sole basis of seismic data. The paper describes the best available algorithms and numerical techniques which can be used for automatic real-time tsunami detection by using sea level measurements. The paper takes into consideration all possible device and locations for the sea level detection

Modal analysis of semi-enclosed basins

Abstract This paper presents a novel technique for the computation of eigenvalues and eigenvectors of partially enclosed basins such as harbours and bays. The procedure makes use of the finite element approximation of the linear shallow water equations, and converts the time-depending problem into an eigenvalues one. The main point of novelty of this research is the mathematical condition used at the boundary that separates the computational domain from the open sea. While classical techniques impose a zero surface elevation (i.e. a nodal line), here an approximate radiation condition is applied. The use of a radiation condition at the open boundary gives a quadratic eigenvalue problem that admits as solution complex eigenvalues and eigenvectors, thus describing the flow in terms of both standing and progressive waves. The new method is applied to an idealized long and narrow harbour, for which an analytical solution of long wave resonance exists, and to the harbour of Marina di Carrara (Italy), for which measurements and previous numerical computation results are available. In both cases the results show good agreement with the available data

A multi-purpose wireless sensor network based on Zigbee technology

Among a wide offer of wireless technologies, ZigBee is one of the most actractive for connecting low–volume devices, such as sensors. This paper aims at presenting a project which is being carried on at Microcomputers and Biomedical Devices laboratory (Department of Computer Science, Faculty of Engineering, University of Pavia, Italy). The goal of the project is the development of a prototype of ZigBee sensors network for temperature monitoring. The idea is to evaluate the capability of ZigBee technology in order to build wireless sensors networks for environmental monitoring. The use of a single chip which integrates a microcontroller and a ZigBee transceiver gives the possibility of developing wireless devices with small dimensions, low power consumption, and a good computing capability

A wireless sensors system for sport studies

A system based on wireless sensors for biomechanical and sport applications is presented. It is currently used to study the interaction between athletes and sport surfaces, such as soccer turves and athletic tracks, with special focus on ankle vibrations. Thanks to a Bluetooth connection, the wireless sensors can communicate with a PC, where data are visualized and elaborated in real time. Thus, the subject under test can move freely, since there are no cable constraints

WESNEP: a wireless environmental sensor network for permafrost studies

The aim of this paper is to give an overview of WESNEP, an environmental wireless sensor network which is currently being developed at the University of Pavia in order to study alpine permafrost. After a brief introduction on environmental sensor networks and the definition of permafrost, the motivation of WESNEP project and the architecture of the network are described, finally the main benefits expected from the project are presented

Modal analysis of semi-enclosed basins

AbstractThis paper presents a novel technique for the computation of eigenvalues and eigenvectors of partially enclosed basins such as harbours and bays. The procedure makes use of the finite element approximation of the linear shallow water equations, and converts the time-depending problem into an eigenvalues one. The main point of novelty of this research is the mathematical condition used at the boundary that separates the computational domain from the open sea. While classical techniques impose a zero surface elevation (i.e. a nodal line), here an approximate radiation condition is applied. The use of a radiation condition at the open boundary gives a quadratic eigenvalue problem that admits as solution complex eigenvalues and eigenvectors, thus describing the flow in terms of both standing and progressive waves. The new method is applied to an idealized long and narrow harbour, for which an analytical solution of long wave resonance exists, and to the harbour of Marina di Carrara (Italy), for which measurements and previous numerical computation results are available. In both cases the results show good agreement with the available data