An Efficient Tool for Wave Climate Analysis in European Coastal Waters

Abstract. We describe a software system that allows even an inexperienced user to estimate the wave statistics at any location along the European coastal zone. The system is composed of a solid, well verified data set, a geographical tool, a modelling section and a statistical package. Their use is fully transparent to the user.     

Submarine canyon morphologies in the Gulf of Palermo (Southern Tyrrhenian Sea) and possible implications for geo-hazard

The continental shelf and the upper slope of the Gulf of Palermo (Southern Tyrrhenian Sea) in the depth interval ranging from 50 to 1,500 m were mapped for the first time with Multi Beam echosounder and high resolution seismic. Seven submarine canyons are confined to the upper slope or indent the shelf-edge and enter the Palermo intraslope basin at a depth of around 1,300 m. The canyons evolved through concurrent top-down turbiditic processes and bottom-up retrogressive mass failures. Most of the mass failure features of the area are related to canyon-shaping processes and only few of them are not confined to the upper slope. In general, these features probably do not represent a significant tsunami hazard along the coast. The geological element that controls the evolution of the canyons and induces sediment instability corresponds to the steep slope gradient, especially in the western sector of the Gulf, where the steepest canyons are located. The structural features mapped in the Palermo offshore contributed to the regulation of mass failure processes in the area, with direct faults and antiform structures coinciding with some of the canyon heads. Furthermore, the occurrence of pockmarks and highs that probably consist of authigenic carbonates above faulted and folded strata suggests a local relationship between structural control, fluid escape processes and mass failure. This paper presents a valuable high-resolution morphologic dataset of the Gulf of Palermo, which constitutes a reliable base for evaluating the geo-hazard potential related to slope failure in the area.     

Seismic isolation of bridges using isolation systems based on flat sliding bearings

Three different isolation systems (IS’s) for bridges and viaducts are considered in the present study. All of them are made of steel-PTFE sliding bearings (SB) to support the weight of the deck and auxiliary devices, based on different technologies and materials (i.e. rubber, steel and shape memory alloys), to provide re-centring and/or additional energy dissipating capability. An extensive numerical investigation has been carried out in order to (i) assess the reliability of different design approaches, (ii) compare the response of different types of IS’s, (iii) evaluate the sensitivity of the structural response to friction variability due to bearing pressure, air temperature and state of lubrication and (iv) identify the response variations caused by changes in the ground motion, bridge and isolation characteristics. The nonlinear time-history analyses have been carried out using a simplified pier-deck model, where the pier is modelled as an elastic cantilever beam and the mass of the deck is connected to the pier through suitable nonlinear elements, simulating the behaviour of the IS. Both artificial and natural seismic excitations have been used in the nonlinear dynamic analyses.     

A Moon-borne electromagnetic calorimeter

We discuss an electromagnetic sampling calorimeter for the detection of very high energy gamma-rays on the Moon, which is based on the use of scintillating cylinders and plates imbedded in the lunar soil. The use of lunar soil as a calorimeter radiator reduces the weight of the material to be transported to the Moon and minimises environmental impact. Plastic scintillator bars inserted into the regolith about 1.5 m are the active elements of this instrument: at the surface, each bar is terminated by a plastic scintillator plate to veto high energy charge particles. The readout system for the scintillator bars and plates are based on recently developed single photon solid state detectors (Silicon Photomultiplier, SiPM), extremely compact, sturdy and sensitive devices suited for detecting small light pulses in a space experiment. The performance of a regolith-scintillator calorimeter is evaluated and the relevant parameters are optimised using a GEANT4 simulation.     

Weathering of granite in Antarctica: I. Light penetration into rock and implications for rock weathering and endolithic communities

Where rocks are composed of translucent minerals, light penetrates the rock and, in so doing, impacts on the thermal conditions. Where minerals are not translucent all the heat transformation must be at the rock surface, and steep thermal gradients can occur. Where light does penetrate, a component of the incoming radiation is transformed to heat at differing depths within the rock, thereby decreasing the thermal gradient. Equally, light transmissive minerals facilitate endolithic communities, which can also play a role in rock weathering. The attribute of light transmission within rock and the impact this has on the resulting thermal conditions has not been considered within rock weathering studies. An attempt was made to monitor the amount of light penetrating the outer 2 mm of coarse granite under Antarctic summer conditions and to evaluate the thermal impact of this. It was found that the amount of light penetration at this site exceeded modeled or postulated values from biological studies and that it could significantly impact the thermal conditions within the outer shell of the rock. Although the resulting data highlighted a number of flaws in the experimental procedure, sufficient information was generated to provide the first assessment of the range of thermal responses due to light transmissive minerals in rock. Copyright © 2007 John Wiley & Sons, Ltd.     

Anchors for the cosmic distance scale: the Cepheid QZ Normae in the open cluster NGC 6067

Cepheids are key to establishing the cosmic distance scale. Therefore it’s important to assess the viability of QZ Nor, V340 Nor, and GU Nor as calibrators for Leavitt’s law via their purported membership in the open cluster NGC 6067. The following suite of evidence confirms that QZ Nor and V340 Nor are members of NGC 6067, whereas GU Nor likely lies in the foreground: (i) existing radial velocities for QZ Nor and V340 Nor agree with that established for the cluster ( $-39.4\pm0.2(\sigma_{\bar {x}}) \pm1.2 (\sigma)~\mbox{km/s}$ ) to within 1 km/s, whereas GU Nor exhibits a markedly smaller value; (ii) a steep velocity-distance gradient characterizes the sight-line toward NGC 6067, thus implying that objects sharing common velocities are nearly equidistant; (iii) a radial profile constructed for NGC 6067 indicates that QZ Nor is within the cluster bounds, despite being 20′ from the cluster center; (iv) new BVJH photometry for NGC 6067 confirms the cluster lies d=1.75±0.10 kpc distant, a result that matches Wesenheit distances computed for QZ Nor/V340 Nor using the Benedict et al. (Astron. J. 133:1810, 2007, HST parallaxes) calibration. QZ Nor is a cluster Cepheid that should be employed as a calibrator for the cosmic distance scale.     

Improving Bayesian analysis for LISA Pathfinder using an efficient Markov Chain Monte Carlo method

We present a parameter estimation procedure based on a Bayesian framework by applying a Markov Chain Monte Carlo algorithm to the calibration of the dynamical parameters of the LISA Pathfinder satellite. The method is based on the Metropolis-Hastings algorithm and a two-stage annealing treatment in order to ensure an effective exploration of the parameter space at the beginning of the chain. We compare two versions of the algorithm with an application to a LISA Pathfinder data analysis problem. The two algorithms share the same heating strategy but with one moving in coordinate directions using proposals from a multivariate Gaussian distribution, while the other uses the natural logarithm of some parameters and proposes jumps in the eigen-space of the Fisher Information matrix. The algorithm proposing jumps in the eigen-space of the Fisher Information matrix demonstrates a higher acceptance rate and a slightly better convergence towards the equilibrium parameter distributions in the application to LISA Pathfinder data. For this experiment, we return parameter values that are all within ～1σ of the injected values. When we analyse the accuracy of our parameter estimation in terms of the effect they have on the force-per-unit of mass noise, we find that the induced errors are three orders of magnitude less than the expected experimental uncertainty in the power spectral density.     

Landslide susceptibility modeling in a landslide prone area in Mazandarn Province,north of Iran: a comparison between GLM,GAM, MARS,and M-AHP methods

Theoretical and Applied Climatology - Landslides are identified as one of the most important natural hazards in many areas throughout the world. The essential purpose of this study is to compare...     

Mapping urban fingerprints of odonyms automatically extracted from French novels

ABSTRACT

In this paper, we propose and discuss a methodology to map the spatial fingerprints of novels and authors based on all of the named urban roads (i.e., odonyms) extracted from novels. We present several ways to explore Parisian space and fictional landscapes by interactively and simultaneously browsing geographical space and literary text. Our project involves building a platform capable of retrieving, mapping and analyzing the occurrences of named urban roads in novels in which the action occurs wholly or partly in Paris. This platform will be used in several areas, such as cultural tourism, urban research, and literary analysis. The paper focuses on extracting named urban roads and mapping the results for a sample of 31 novels published between 1800 and 1914. Two approaches to the annotation of odonyms are compared. First, we describe a proof of concept using queries made via the TXM textual analysis platform. Then, we describe an automatic process using a natural language processing (NLP) method. Additionally, we mention how the geosemantic information annotated from the text (e.g., a structure combining verbs, spatial relations, named entities, adjectives and adverbs) can be used to automatically characterize the semantic content associated with named urban roads.