2,317 research outputs found
Acoustic Noise Levels Predictive Model Based on Time Series Analysis
No full textThe need for noise monitoring and prediction in urban areas is a relevant problem in large cities and growing agglomerations. In fact, besides air pollution and electromagnetic fields, acoustical noise is considered one of the most hazardous agent, in relation to the effects on human health. A large set of predictive models exists in literature, especially for transportation means noise. In this paper, the authors present an innovative approach based on Time Series Analysis (TSA). This kind of models are largely adopted in several disciplines and will show very good performances and adaptability to environmental noise prediction. After a tuning phase, performed on actual data, different validation phases, on different data sets, are presented.
Results, expressed in terms of variation between actual data and forecast, show that this model is suitable for almost stationary noise data sets. Finally, an analysis on tuning data set size is performed, giving interesting results and useful advices for model applications to noise assessment
Analysis of Traffic Noise in a Road Intersection Configuration
No full textAcoustical noise produced by vehicular traffic depends on many parameters, including the geometry and the general features of the road. The presence of a conflicting point, i.e. an intersection, strongly affects and modifies the simulation strategy of noise in urban environments, that is usually performed with statistical models tuned on experimental data related to standard condition (free flow traffic, intermediate vehicular volumes, etc.). In this paper, the author presents the analysis of an intersection case study in proximity of Salerno University, performed by means of experimental measurements and software simulations. The chosen area presents interesting features because of the priority rights on the principal road and because of the relevant amount of vehicles and buses, mainly due to the University students and personnel that transit in the intersection, especially during rush hours. The aid of a predictive software is highlighted, together with the shortcomings of a simulation strategy that does not take into account traffic dynamics. The analogy between electrical current and vehicular flow is sketched and used in the roads vehicles volume definition
Advanced Tools for Traffic Noise Modelling and Prediction
No full textEnvironmental impact studies are strongly related to road traffic noise, especially in urban areas. A long term exposure to road traffic noise, in fact, can lead to relevant effects, both auditory (e.g. sleep disturbance, hearing loss, etc.) or not auditory (e.g. stress, anxiety, cardiovascular problems, etc.). A proper modelling of noise production and propagation is a challenging issue, especially in areas where the complexity of sources, receivers and other objects makes difficult to use standard predictive formulas, such as the usual Traffic Noise predictive Models (TNMs). The collection of experimental data is always advisable, in order to control the predictive tools and eventually tune their parameters. In this paper, the author presents a set of advanced tools for noise modelling, particularly aimed at the prediction of non-conventional situations, such as road intersections, traffic jams, extreme traffic flow, etc., where the standard TNMs usually fail. The main idea is to implement a dynamical approach in the traffic noise prediction, i.e. to include the dependence of noise emission by kinematical parameters, such as speed, position and eventually acceleration. This can be achieved by means of different approaches, some of them resumed in the paper, for instance cellular automata, traffic theory (Fundamental Diagram), source power dependence from the speed, etc.. The implementation of these models in easy to use tools represents the new horizon in traffic noise prediction
Nuovo complesso parrocchiale dello Spirito Santo, Benevento (IT) - FINALISTA SECONDA FASE
No full textProgetto per il nuovo complesso parrocchiale dello Spirito Santo a Benevento (chiesa, locali di ministero pastorale, canonica, aree esterne). Il progetto è stato elaborato nell'ambito del Concorso di idee in due fasi indetto dall'Arcidiocesi di Benevento e dall'Ufficio Nazionale per i beni culturali ecclesiastici e l'edilizia di culto della CEI. Progetto finalista nella seconda fase della procedura concorsuale. Gruppo di progettazione: Manuela Antoniciello (Architetto Capogruppo); Felice De Silva, Renato Capozzi, Federica Visconti ; (Consulenti Scientifici Esperti Di Progettazione Architettonica); Carmine Andreotti (Consulente Esperto In Strutture); Claudio Guarnaccia
(Consulente Scientifico Esperto Di Acustica Ambientale E Architettonica); Don Marco Valentini (Liturgista); Oliviero Rainaldi (Artista); Salvatore Giugliano, Giuseppe Sabatino, Giammarco Gioia (Collaboratori)
Acoustical Noise Analysis in Road Intersections: a Case Study
No full textThe modelling and the prediction of noise coming from vehicular flows is strongly related with the geometry and the general features of the road, including the presence of conflicting points. In an intersection configuration, in fact, noise cannot be predicted in a standard way, since the traffic slope depends on many random factors, such as priority, signals, traffic lights, driving behaviour, etc. In this paper, the author focuses on the noise prediction problems related to road intersections and on the analogy between electrical current and vehicular flow. An experimental activity on a case study in the Salerno University campus is presented and the results are compared with simulations made by a predictive software
Using the Sodium Carboxymethylcellulose (CMC) as viscosity modifier to model the interstitial fluid in laboratory debris flows
No full textThis work refers about the use of Sodium Carboxymethylcellulose (CMC) as viscosity modifier of the interstitial fluid in laboratory debris flows. The transparency feature of CMC-water solutions allows to inquire on the kinematics of such events. In facts, velocity of solid grains can be detected via PIV techniques at the transparent walls of an open channel flow laboratory.
However, the main interest arises from the possibility of making CMC-water solutions of desired dynamic viscosities. This allows establishing a double model of similitude by which the concentration of CMC, to be used in laboratory for the reproduction of a specific real debris flow event, can be derived. The relation between the dynamic viscosity, temperature and concentration is obtained for the prototype and, hence, for the model by a double regression on viscometric measurements
Industrial Settlements Acoustic Noise Impact Study by Predictive Software and Computational Approach
No full textThe usage of predictive software in environmental impact study is very frequent. In this paper, an acoustic noise analysis of an operating industrial plant is performed, both in the internal and in the external environment, with the aid of two different predictive software. A measurement campaign is designed and performed, according to quality procedure, in order to describe the internal acoustic climate, to characterize the noise sources, that are the production machines and operations, and to have reference values to be used in the tuning of the model. With the source characterization, the internal simulations are performed and compared with measured levels. Finally, the simulations of the external surrounding area are made, in two different operating conditions, and combined with the internal simulations. In this way, a procedure to perform complete predictions, both inside and outside the plant, is given, showing, in the validation test, a good agreement with
the measured values
Relativistic Effects in a moving Point Charge
No full textUsing the transformation law of the electromagnetic field between two inertial frames, the Lorentz force that acts on a charged particle moving in a magnetic field, is obtained.
It is shown why this force, despite being of relativistic nature, manifests itself at any value of speed of the moving charge.
In addition, using the same transformation laws, the electromagnetic field generated by a charge that moves with constant speed, in the direction perpendicular to the speed, is calculated
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