Performances of the Italian seismic network, 1985-2002: the hidden thing

Seismic data users and people managing a sesimic network are both interested in the potentiality of the data, with the difference that the former look at stability, the second at improvements. In this work we measure the performances of the Italian Telemetered Seismic Network in 1985-2002 by defining basic significant parameters and studying their evolution during the years. Then, we deal with the geological methods used to characterise or to plan a seismic station deployment in a few cases. Last, we define the gain of the network as the percentage of located earthquakes with respect to the total recorded earthquakes. By analysing the distribution of non-located ("missed") earthquakes, we suggest possible actions to take in order to increase the gain. Results show that completeness magnitude is 2.4 in the average over the analysed period, and it can be as low as 2.2 when we consider non-located earthquakes as well. Parameters such as the distance between an earthquake and the closest station, and the RMS location decrease with time, reflecting improvements in the location quality. Methods for geologic and seismological characterisation of a possible station site also proved to be effective. Finally, we represent the number of missed earthquakes at each station, showing that nine stations control more that 50% of all missed earthquakes, and suggesting areas in Italy where the network might be easily improved.Comment: 17 pages, 1 table, 11 figures. Submitted to Annals of Geophysic

A Comparison Between Raw Material and Technologies for a Sustainable Biodiesel Production Industry

The increasing interest in Biodiesel production is due to its source, which is renewable, sustainable, and biodegradable as vegetable oils are. This biofuel does not produce CO neither particle pollutant emissions; and it produces a reduced quantity of CO2 when compared to regular diesel. This interest has also lead to wider debate about the use of refined vegetable oils as a raw material for food or fuel. Normally, Biodiesel production is carried on by using refined oil and sodium hydroxide due to their short residence time and the widespread knowledge about this process. Nevertheless, several new options as regards sources and technologies are being studied on biodiesel production. This chapter discusses the different possibilities regarding raw materials, considering their advantages and disadvantages. It also presents a short comparison of the different technologies for biodiesel production, their strengths and weaknesses in relation to the different raw materials and alcohols. A short summary of the different alcohol and their influences will also be introduced.Fil: Marchetti, Jorge Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; Argentin

Advanced Composite Materials by Resin Transfer Molding for Aerospace Applications

Competitiveness drives the aerospace industries to investigate new technology solutions to address market pressure and high-tech demands. The global objective is to reduce to half the amount of fuel by 2020 and at least 70% less by 2025 with respect to the Boeing 777, one of the most efficient aircraft, which is made entirely of carbon fiber. The weight saving to increase payload and the reductions of the cost/time of the production cycle are imperative targets. For these reasons, aerospace companies, which are traditionally based on the use of metal alloys, have been focusing for past decade on composite materials. The main advantages of composites with respect to metals, that are resistance to corrosion and fatigue and high performance/weight ratios, are a set of qualities for winning the current and future aerospace applications. Obviously, this is possible only through the development of economically competitive technologies. The Resin Transfer Molding (RTM) is one of the most promising technology available today. RTM is capable of making large complex three-dimensional part with high mechanical performance, tight dimensional tolerance and high surface finish. A good design by RTM leads to fabricate three-dimensional near-net-shape complex parts, offering production of cost-effective structural parts in medium-volume quantities using low cost tooling. In addition to these advantages, the problems of the joints, typical of the metal structures, can be eliminated by integration of inserts

Damages and Benefits of Certification: A perspective from an Independent Assessment Body

The paper investigates on the nature of software certification and its reasons of being. The numerous factors that impact on the achievement of its purposes are discussed, and also compared in the cases of Proprietary Software and Open Source Software. Some relevant features of a certification process for Open Source Software are finally proposed

Stochastic analysis of the vibrations of an uncertain composite truss for space applications

A hybrid technique to model the effects of mechanical uncertainties on the structural response of large composite trusses for space application is presented and discussed: the proposed method is based on the Monte-Carlo evaluation of finite element stochastic weighted integrals, which allows decoupling the structural discretization mesh from the stochastic one. A benchmark problem, regarding the modal analysis and the harmonic response of an uncertain composite truss, is studied by means of the proposed method: the full statistics of the truss response variables are calculated ty Monte-Carlo based simulations and compared to those obtained by perturbative approximated approaches. The implications of the results here obtained onto the design strategy of structures affected by sensible uncertainty levels, as those made of composites, are discussed. (c) 2005 Elsevier Ltd. All rights reserved

Economics of biodiesel production: Review

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Variabilità dei principi attivi in <i>Hypericum perforatum</i> L. vegetante in Sardegna

Vista la grande importanza farmacologica che sta rivestendo l’estratto d’iperico nella cura della depressione (2-3) abbiamo ritenuto interessante indagare la specie spontanea presente in Sardegna. Le analisi sono state effettuate via HPLC

Economic Assessment of Biodiesel Production

Biodiesel production as well as consumption in the European nations are augmenting, taking into account the uncertainties connected to fossil fuel reserves and the related natural effects of their use. This biofuel can be generated from numerous oil-rich feedstocks and by using different processing technologies. Therefore, the techno-economic assessment for biodiesel production becomes of high relevance to make critical decisions under uncertainties that are essential for the successful implementation of the process on an industrial scale. The economic aspects of using different triglycerides and non-triglycerides based lipid biomass as well as the processing technologies for biodiesel production are thoroughly discussed and compared in this chapteracceptedVersio

Kinetic study of the esterification of free fatty acid and ethanol in the presence of triglycerides using solid resins as catalyst

Biodiesel production is gaining more and more relevance due to its environmental advantages and because of the world situation of petroleum: decreases of reserves, augmentation of prices etc. Biodiesel is produced by transesterification of triglycerides; however, it can also be generated by the esterification of fatty acid, normally considered as an impurity. The evolution of the reaction when using oleic acid (diluted in triglycerides) and ethanol, in the presence of a heterogeneous catalyst, has been studied. Kinetics expression for the esterification reaction as well as for the esterification and transesterification taking place simultaneously have been developed and fit with the experimental data. It is shown that, when both reactions are being taking into account, the kinetics fits the experimental data better since it does consider the interaction between all the compounds involved. The kinetics expression obtained represented satisfactorily the experimental information for several operations conditions.Fil: Jasen, Paula Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; ArgentinaFil: Marchetti, Jorge Mario. Norwegian University of Life Sciences; Noruega. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Física del Sur. Universidad Nacional del Sur. Departamento de Física. Instituto de Física del Sur; Argentin

Techno-economic feasibility of producing biodiesel from acidic oil using sulfuric acid and calcium oxide as catalysts

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