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Funder: Carl-Zeiss-Stiftung; doi: http://dx.doi.org/10.13039/100007569, Funder: German Scholars Organization e.V., We consider quantum stochastic processes and discuss a level 2.5 large deviation formalism providing an explicit and complete characterisation of fluctuations of time-averaged quantities, in the large-time limit. We analyse two classes of quantum stochastic dynamics, within this framework. The first class consists of the quantum jump trajectories related to photon detection; the second is quantum state diffusion related to homodyne detection. For both processes, we present the level 2.5 functional starting from the corresponding quantum stochastic Schrödinger equation and we discuss connections of these functionals to optimal control theory.

In this paper, the dimensionless stage-discharge relation for a sharp-crested triangular labyrinth weir, determined in a previous study, is initially tested by some experimental runs carried out in a laboratory flume. According to this relationship, the flow magnification is affected by the length-magnification ratio and the head to one cycle width ratio. The measurements allowed to test the applicability of this dimensionless relation for different values of both the angle of the sidewall to the main flow direction and the weir height. Finally, the proposed dimensionless equation was also tested by using experimental measurements carried out for broad-crested triangular labyrinth weir.

We consider two chains, each made of $N$ independent oscillators, immersed in a common thermal bath and study the dynamics of their mutual quantum correlations in the thermodynamic, large-$N$ limit. We show that dissipation and noise due to the presence of the external environment are able to generate collective quantum correlations between the two chains at the mesoscopic level. The created collective quantum entanglement between the two many-body systems turns out to be rather robust, surviving for asymptotically long times even for non vanishing bath temperatures., LaTeX, 38 pages, 7 figures

Recent experimental results point to the existence of coherent quantum phenomena in systems made of a large number of particles, despite the fact that for many-body systems the presence of decoherence is hardly negligible and emerging classicality is expected. This behaviour hinges on collective observables, named quantum fluctuations, that retain a quantum character even in the thermodynamic limit: they provide useful tools for studying properties of many-body systems at the mesoscopic level, in between the quantum microscopic scale and the classical macroscopic one. We hereby present the general theory of quantum fluctuations in mesoscopic systems and study their dynamics in a quantum open system setting, taking into account the unavoidable effects of dissipation and noise induced by the external environment. As in the case of microscopic systems, decoherence is not always the only dominating effect at the mesoscopic scale: certain type of environments can provide means for entangling collective fluctuations through a purely noisy mechanism., Comment: 51 pages, LaTeX

In this work the data, obtained for the three vehicles (sedan, SUV and Pick Up), tested in previous works, are compared. Following the results found in the literature, particular emphasis is done on the speed of the teenager cyclist head at the instant of impact and the diagrams of the head speed and the chest obtained in the simulations are shown. The speed of the head is that absolute, and this is used for processing the data and the subsequent determination of the best values of the three geometric actual parameters identified in front of the vehicle. Absolute speed is preferred because using the relative speed respect to vehicle, some amounts that cannot be disregarded are omitted from the evaluation. The chosen speed is 30 km/h because higher values appear too dependent on the mass of the vehicle, while lower values may not result in serious injury and are therefore less attractive. The procedure, to obtain the optimal values of the height of the bumper, the height of the bonnet and of the inclination angle of the bonnet is illustrated in the case the side impact vehicle-teenager cyclist. The conclusion is made that analogous procedure can be applied to HIC values.

Rainfall erosivity is defined as the potential of the rain to cause erosion, and it can be represented by rainfall kinetic power. At first in this paper, the raindrop size distributions (DSD) measured by an optical disdrometer located at Palermo in the period June 2006–March 2014 and aggregated for intensity classes, are presented. Then an analysis of raindrop size characteristics is carried out, and the reliability of Ulbrich's distribution, using both the maximum likelihood and momentum estimate parameter methods, is tested. The raindrop size measurements are used to determine the experimental rainfall kinetic power values, which are compared with the ones calculated by a theoretically deduced relationship. This analysis demonstrates that the kinetic power is strictly related to the median volume diameter of DSD. Finally, the reliability of the simplest Marshall and Palmer exponential DSD for estimating the rainfall kinetic power is demonstrated. Copyright © 2015 John Wiley & Sons, Ltd.

The study of the injury caused by Pick-up vehicle-teenage cyclist crash is presented in this paper. The vehicle has high frontal part, in order to compare the results with those obtained previously in the sedan and SUV - teenage cyclist crash. No variation is executed on the model of the teenage cyclist and the bike. Three different positions are analyzed: front, rear and lateral position. The injury on the cyclist head is examined by HIC criterion, in the way indicated in the rules. Correlation HIC – AIS is used to calculate the lethality of the injuries. A comparison is made between the results of the simulations for Pick up, SUV and sedan, concluding that the injury of the head is more dangerous for Pick-up impact than SUV and the sedan, but only at the maximum speed (50 km/h). This value of the speed can be considered critical, since HIC values are very high for all the three vehicles. The more dangerous injury is the side impact. A further comparison is done between the impact points of the three vehicles concluding that both the shape of the bonnet that the height of the front part must be studied carefully in order to reduce the damage to cyclists and pedestrians.

Data obtained in teenage cyclist impact against three vehicles (sedan, SUV and Pick Up), tested in previous works, are analyzed to verify the theoretical results by the coupling of momentum conservation principle and energy conservation principle. The speed of vehicle and thorax are compared with theoretical ones, obtaining an excellent agreement. Following the results found in the literature, particular emphasis is done on teenager cyclist thorax and head speeds, indicating that the cyclist speed can be theoretically until 1,41 times the impact speed, while greater values, until 2, are obtained in the simulations. A small slowing of the vehicle is found theoretically and in the simulations, due to kinetic energy transfer. A small component of the vehicle speed exists in the orthogonal plane to the motion, due, for example, to the compression of the rider body on the bonnet. A parameter is determined using all the data in term of thorax speed, in all the impact speeds and in all the relative positions; its value does not appear depending on the vehicle mass. It allows the subsequent determination of the best values of three geometric actual parameters identified in front of the vehicle: bumper height, bonnet height and bonnet inclination angle, by interpolation with a second order curve, by making the conclusion that the frontal part of the vehicle may be designed in order to reduce the injury.

The study of the injury caused by vehicle-teenage cyclist crash is presented in this paper. The results of the crash with three vehicles: sedan, SUV and Pick up are compared. Three different positions are analyzed: front, rear and lateral position. The injury on the cyclist head is examined by HIC criterion, in the way indicated by the rules. A comparison is done between the results of the simulations for Pick up, SUV and sedan, concluding that the injury of the head is more dangerous for Pick-up impact than SUV or the sedan, but only at greater speed than 40 km/h. Teenage cyclist is more likely to suffer an injury to the chest in rear impacts with the sedan, because 3 ms values remain above the values obtained with the SUV and Pick up. Unlike Pick up could cause greater injury to the chest in the front and side impact because of greater height from the ground. The vehicle mass has not great importance, but only to low speed. Consideration is made that teenage cyclist has a better chance of surviving in the front impact collision than adult pedestrian, because HIC values remain consistently below the determined values. A further comparison is done between the impact points of the three vehicles concluding that both the shape of the bonnet and the height of the front part must be studied carefully in order to reduce the damage to cyclists and pedestrians. At last the throwing distance are calculated and compared with the literature data, concluding that they are strongly dependent on the relative position.

Le situazioni di impatto e la dinamica di ciclista e pedone sono le informazioni fondamentali per lo sviluppo di soluzioni efficaci per migliorare la protezione del pedone e del ciclista in caso di urto con autovetture. La casistica degli incidenti a Palermo, negli ultimi anni, avvenuti su strade urbane (84%) che coinvolgono adolescenti (6,4%), mostra che i ciclisti hanno in genere una posizione di impatto superiore rispetto al pedone, con una quota maggiore di lesioni per urti nella zona del parabrezza. In questo lavoro è eseguita la simulazione dinamica per lo studio delle lesioni alla testa e al torace dell’adolescente, tra una bicicletta generica e un modello di auto che presenta caratteristiche vantaggiose per la sicurezza del pedone o del ciclista. Il software SimWise (Visual Nastran) è stato usato per la simulazione multibody dell’impatto; il modello antropomorfo, l'auto e le biciclette sono quelli utilizzati in lavori precedenti. L'attenzione è su un ciclista adolescente, perché i relativi dati di lesione si trovano in letteratura con difficoltà. I dodici test d’impatto completo (auto contro ciclista) hanno come parametri principali: velocità del veicolo (20, 30, 40 e 50 km/h), con tre diverse posizioni del ciclista rispetto al veicolo: frontale, laterale e posteriore. La posizione di impatto della testa (sopra il cofano, nel parabrezza), determinato dalla prova di crash, mostra che la protezione del ciclista dovrebbe essere migliorata nella zona più alta del parabrezza, rispetto a quelle pedonali. La ferita alla testa viene analizzata utilizzando il parametro HIC e la ferita al torace è analizzata secondo il criterio dei 3 ms; viene calcolata la probabilità AIS 4 +, concludendo che la lesione alla testa è più pericolosa in caso di pedone adolescente, mentre la ferita della cassa toracica è più pericolosa nel caso di ciclista adolescente. Inoltre il ciclista adolescente ha una maggiore possibilità di sopravvivenza rispetto al ciclista adulto. Incidentologia e simulazioni mostrano che il parabrezza è una posizione di impatto frequente per testa e torace.

In order to measure soil loss in equipped plots the estimate of the weight of solid material intercepted at their lower end is required. At the experimental area of Sparacia, Sicily, the runoff produced by an erosive event is collected within storage tanks with a capacity of about 1m3. In this paper, the use of a new sampler is proposed to measure easily the weight of solid material eroded from an experimental plot and collected into a storage tank. The sampler is a cylinder having a closing valve at the bottom. Two different series of runs were carried out both to test the reliability of the sampler and to establish a sampling procedure, respectively. An analysis of various sampling configurations usable in the field differentiated by the number and location of sampling verticals in the tank cross-section was finally carried out. The results of the present investigation are that the concentration measurement by the sampler was more accurate than that obtained by other methods involving a collection tank, agitation and sampling of the suspension. This sampler is cheap and usable in combination with a quick field sampling procedure which is particularly advisable when the number of plots equipped at an experimental area is large. The sampler was tested using a clay soil contained within cylinders and a cubic tank, but it appeared also to be usable with coarser sediment than clay and in combination with tanks having a different shape.

This paper presents the results of an experimental investigation on the roller length of both classical and B-jumps on smooth beds. Using the measurements conducted in this investigation and those available in the literature, a new relationship is proposed for estimating the roller length of classical and B-jumps on smooth beds. Finally, it is demonstrated that the proposed equation is also applicable to estimate the roller length of hydraulic jumps on rough horizontal beds.

Lo studio del distacco delle particelle di suolo operato dalla pioggia richiede la conoscenza delle caratteristiche erosive della precipitazione. Nella memoria, dopo aver richiamato i presupposti teorici della legge di Ulbrich e le espressioni della potenza cinetica da essa deducibili, viene presentata una verifica di applicabilita della suddetta distribuzione teorica sulla base delle distribuzioni dimensionali delle gocce di pioggia rilevate mediante un disdrometro ottico installato presso la sezione Idraulica del Dipartimento dei Sistemi Agro-Ambientali dell’Universita di Palermo. Viene proposta, infine, una verifica sperimentale dell’equazione di Wischmeier e Smith per il calcolo della potenza cinetica

We study the emergent dynamics resulting from the infinite volume limit of the mean-field dissipative dynamics of quantum spin chains with clustering, but not time-invariant states. We focus upon three algebras of spin operators: the commutative algebra of mean-field operators, the quasi-local algebra of microscopic, local operators and the collective algebra of fluctuation operators. In the infinite volume limit, mean-field operators behave as time-dependent, commuting scalar macroscopic averages while quasi-local operators, despite the dissipative underlying dynamics, evolve unitarily in a typical non-Markovian fashion. Instead, the algebra of collective fluctuations, which is of bosonic type with time-dependent canonical commutation relations, undergoes a time-evolution that retains the dissipative character of the underlying microscopic dynamics and exhibits non-linear features. These latter disappear by extending the time-evolution to a larger algebra where it is represented by a continuous one-parameter semigroup of completely positive maps. The corresponding generator is not of Lindblad form and displays mixed quantum-classical features, thus indicating that peculiar hybrid systems may naturally emerge at the level of quantum fluctuations in many-body quantum systems endowed with non time-invariant states., 65 pages

The study of the injury caused by the vehicle-teenage cyclist crash is presented in this paper. The vehicle is a SUV, with high frontal part, in order to compare the results with those obtained previously in the sedan- teenage cyclist crash and begin a study of the influence of the frontal shape of the vehicle. No variation is executed on the model of the teenage cyclist and the bike. Three different positions are analyzed: front, rear and lateral position. The injury on the cyclist head is examined by HIC criterion, in the way indicated in the rules. Correlation HIC – AIS is used to calculate the lethality of the injuries. The principal conclusion is done that the injury of the head is more dangerous for the SUV impact than the sedan, but only at the maximum speed (50 km/h). The injury to the chest is analyzed by 3 ms criterion; the injury is greater for the SUV impact than the sedan, but the entity is strongly dependent on the cyclist position. A comparison is executed with both the teenage and adult pedestrian concluding that the pedestrian is subjected to greater injury, because the bike absorbs a part of the energy in the front and side crash. The more dangerous injury is the telescoping. A further comparison show that the shape of the bonnet and the height of the frontal part have to be studied in an accurate way to reduce the injury to pedestrians and cyclists.

The study of the crash between normal sedan and teenage cyclist was examined in previous paper, and is here continued analyzing the influence of the front part of the vehicle in the injury caused by the accident. The vehicle is a SUV, with high frontal part. No variation is executed on the model of the teenage cyclist and the bike. The position of the teenage cyclist regard to SUV is the same: three different positions are analyzed: front, rear and lateral position. The injury on the cyclist head is examined by HIC criterion, in the way indicated in the rules. Correlation HIC – AIS is used to calculate the lethality of the injuries. The work is arranged to calculate the damage to the chest by 3 ms criterion, which result is not yet ready. The principal conclusion is done that the injury of the head is more dangerous for the SUV impact than the sedan, but only to the maximum speed (50 km/h). A comparison is executed with the teenage pedestrian concluding that the pedestrian is subjected to greater injury, because the bike absorbs a part of the energy in the front and side crash. The more dangerous injury is the telescoping.

The vehicle-bicyclist impact is studied in this paper. After analysis of the accidents in Palermo in the last years, the multibody simulation of the crash is executed by making use of Visual Nastran. Dummy, car and bicycle are those used in previous works. The attention is on a teenage cyclist, because the data on this argument are found in literature with difficulty. The impact is simulated at four different speeds until 50 km/h, with three different positions of the cyclist relative to the vehicle: frontal, side and rear. In particular the injury of the head is analyzed using the parameter HIC and the chest injury is analyzed by 3 ms criterion; the likelihood AIS 4+ is calculated, concluding that head injury is more dangerous in the case of teenage pedestrian, while chest injury is more dangerous in the case of the cyclist.

Information on impact locations, impact situations and cyclist and pedestrian dynamics in impacts with passenger cars is fundamental for the development of effective solutions to improve cyclist and pedestrian protection. Accidentology research shows that cyclists typically have a higher impact location than the pedestrian, with a larger share of injuries from the windscreen area. Majority of accidents in Palermo, in the last years, happens at urban street (84%) that involve teenager (6.4%). In this paper simulation study captures dynamics and injuries to head and chest for teenager between a generic bicycle and a car model that is suitable for pedestrian or cyclist safety. Multibody simulation of the crash is executed by making use of Visual Nastran. Dummy, car and bicycle are those used in previous works. The attention is on a teenage cyclist, because the data on this scope are found in literature with difficulty. Twelve full ‐scale crash tests (passenger car versus cyclist) have as main parameters: vehicle speed (20, 30, 40 and 50 km/h), with three different positions of the cyclist respect to the vehicle: frontal, side and rear. Head impact location (top of bonnet, windscreen), given by crash test, shows that cyclist protection should be higher in the windscreen area than pedestrian countermeasures. In particular the injury of the head is analyzed using the parameter HIC and the chest injury is analyzed by 3 ms criterion; the likelihood AIS 4+ is calculated, concluding that head injury is more dangerous in the case of teenage pedestrian, while chest injury is more dangerous in the case of the teenage cyclist; moreover he has greater possibility of survival than the adult cyclist. Accidentology, simulation and crash test show that the windscreen is a frequent head and chest impact location.

Vegetation altering hydrodynamic conditions of an open channel flow controls the exchanges of sediment, nutrients and contaminants. In this paper the turbulence structure of open-channel flow over a flexible grass vegetation is investigated. Velocity measurements were carried out, in a rectangular flume, using a 2D-ADV (Acoustic Doppler Velocimeter) for different values of stem concentration, water discharge, and bed slope. The experimental results showed that: 1) the maximum value of the longitudinal turbulence intensity occurs at a water depth close to the bent vegetation height; 2) the turbulence intensity damps for increasing values of the stem concentration; 3) above the vegetation height, an exponential distribution, similar to Nezu’s law, can be fitted to the measured longitudinal turbulence intensity profile. Finally, a new relative turbulence intensity distribution is proposed and fitted to the measured profiles. This relative turbulence intensity distribution needs the estimate of two parameters coinciding with the vegetation height and the water depth at which the maximum flow velocity occurs.

This paper presents the results of an experimental investigation on the hydraulic jump on horizontal rough beds. Experiments were carried out to study the effect of bed roughness on both the sequent depth ratio and the roller length. The investigation allowed the writers to positively test the reliability of a new solution of the momentum equation for the sequent depth ratio as a function of the Froude number and the ratio between the roughness height and the upstream supercritical flow depth. The applicability of some empirical relationships for estimating the roller length was also tested.

In this short note, the experimental data of Wilson and Horritt (2002.Hydrological Processes16: 2589–2598), jointlywith the measurements by Kouwenet al. (1969.Journal of Irrigation and Drainage Division, ASCE95: 329–342)and by Raffaelliet al. (2002 InProceedings XXVIII Convegno di Idraulica e Costruzioni Idrauliche, Cosenza, Italy;223–230), arefirstly used to test Kouwen’s approach. All experimental data are then used to calibrate aflow resistanceequation that was theoretically deduced by dimensional analysis and self-similarity theory

Nowadays, the influence of the vehicular traffic on the degradation of urban atmosphere is focused on by researchers belonging to different fields in view of its prime importance for public health. The control of exhaust gases emission is primary in order to keep air pollution below the specified limits of the laws in force. In previous works the “medium car” characterises a country in modelling a pollutant in urban areas. This is the central parameter of a forecasting model proposed by Pignato and LoMastro, of pollutant concentration near urban cross-road with traffic lights in continue queue and platoon flow. The proofs have been carried on two classes of displacement vehicles and four classes of age considering the circulating park. We have found the trend of the pollutants emission vs. rpm in the phase of “acceleration” and in the phase of “stopping and deceleration”. Applying the model proposed it is possible forecast the maximum concentration of the considered pollutant in platoon flow near urban cross road with traffic light, without the bus presence. The "medium car", is the fictitious vehicle polluting like that real one of the platoon most probable composition. In steady-state conditions, the vehicular traffic is governed by stoppages at crossroad assuming the pattern of a "platoon flow", or crossing by "platoons". Any vehicle of the platoon undergoes the following kinematics phases: entering the queue, deceleration within the queue, waiting and starting from rest. With the laboratory equipment of AMAT" Azienda Municipalizzata AutoTrasporti" of Palermo, supplied with a torque dynamometer and necessary instrumentation, we measured the emission of some pollutants, as CO, NOx, emitted from vehicles submitted to the phases and conditions above described