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The paper extends recently developed idea of stable evaluation of the Gaussian kernel. Owing to this, the Gaussian radial basis function that is sensitive to the shape parameter can be stably evaluated and applied to interpolation problems as well as to solve differential equations, giving highly accurate results. But it can be done only with grids being the Cartesian product of sets of points, what limits the use of this idea to rectangular domains. In the present paper, by the association of an appropriate transformation with the mentioned method, the latter is applied to solve differential equations on quadrilateral irregular domains. As an example a biharmonic problem is taken into consideration. The numerical tests show high accuracy and usefulness of the method.. [ABSTRACT FROM AUTHOR]

The present work deals with the characterization of the conformational, dynamical, and rheological properties of melts of entangled n-arm star polyethylene chains. All simulations were performed with the EMSIPON code (Engine for Mesoscopic Simulations of Polymer Networks). The EMSIPON code has been extended in a way that can describe any kind of branched polymer of arbitrary chemical constitution. Motion at the bead level is tracked via Brownian Dynamics. The long-time dynamics is dominated by topological constraints (entanglements) modeled by slip-springs (SLS), i.e., dynamical entropic springs connecting different chains, whose ends can hop along chain backbones. The behavior of SLS at a branch point is pivotal to the proper description of the dynamics; thus, the rules dictating the dynamics of SLS near a branch point were carefully investigated. We test our model on 3-arm star polyethylene melts; the viscoelastic properties obtained agree with experimental measurements. [ABSTRACT FROM AUTHOR]

The search and development of alternative energy sources for human life is a priority task for modern society. One of the promising directions is the use of biogas as a source of thermal energy for power plants. It is established that the main difference between biogas and natural gas is caused by the presence of more than 30% of carbon dioxide in its composition, which affects the density, calorific value and speed of flame propagation. To burn biogas in modern power plants that use natural gas, it is necessary to modify the burner devices. For qualitative modification of burner devices, it is necessary to have theoretical data on effective modes of biogas combustion. In combustion, we present a model of turbulence k-s (realizable), which allows us to model the combustion of natural gas and biogas with tangential air swirl. The paper presents qualitative characteristics of biogas that allow us to analyze and develop a theory about efficient combustion of biogas in power plants. [ABSTRACT FROM AUTHOR]

Prevention of further atmospheric air pollution and reduction of toxic substances emission is one of the goals of state policy in the field of energy. In this regard, the search for new solutions that prevent negative impact on the environment is one of the priority tasks for modern society. An alternative, but less efficient fuel compared to natural gas is biogas extracted from organic waste. The high content of carbon dioxide in biogas reduces the calorific value, while flame detachment from the burner is also observed. One of the promising options for reducing the negative impact of energy on the environment is the combined burning of natural gas and biogas. For the combined burning of natural gas and biogas in operating power-generating boiler, it is necessary to reconstruct the burner devices installed on them. For a high-quality reconstruction of burner devices, it is important to have theoretical data on the effect of combustion combinations on the content of toxic combustion products in the flue gases of power-generating boilers. In this paper, a turbulence model k - ε (realizable) is presented, which allows simulating the combustion process of a fuel-air mixture. The quantitative content of NOx, CO2 in the products of combustion of fuel combinations - natural gas, biogas, natural gas / biogas is presented. [ABSTRACT FROM AUTHOR]

The bidomain and monodomain models are types of nonlinear reaction-diffusion system and are widely used to study cardiac electrical activity. The numerical simulation of these models calls for extremely fine meshes to accurately predict the depolarization and repolarization wave fronts, which leads to huge computational challenges. In this paper, we will show the advantage of a parallel mesh adaptation method for solving the monodomain model. A comparison between parallel adapted and uniform meshes will be presented. The computational efficiency of the proposed methodology is assessed using an example of spiral wave. [ABSTRACT FROM AUTHOR]

The fundamental tool for studying complex gas-dynamic processes occurring in the boundary layer under non- stationary conditions is mathematical modeling, which allows for reliable accuracy to conduct comprehensive research and development of technical solutions necessary to create an efficient and resource-saving energy. A promising area of research is the search and development of methods for managing the boundary layer of gas flows. To date, there are many methods for managing the boundary layer that allow to intensify or reduce exchange processes in the boundary layer [1], including in power plants. One of the most effective, but little-studied methods is the method of passive influence on the boundary layer of the gas flow, based on the use of a damping surface [2]. The impact of the damping surface leads to a decrease in the intensity of generation of turbulent vortices, which in turn reduces the friction resistance and heat exchange in the boundary layer [3]. The paper presents a method for modeling a turbulent boundary layer, which allows calculating the impact of the damping surface on the dynamic processes occurring in the boundary layer of the gas flow. In addition, the modeling technique includes the ability to study the boundary layer for the most common gases in the technology, such as air and The paper presents the results of a numerical study of the boundary layer on a damping and smooth surface in graphical form. Research conditions: a flat surface with a high-speed gas flow was simulated. [ABSTRACT FROM AUTHOR]

This paper focuses on coarse-grained (or mesoscopic) simulations of bidisperse cis-1,4-polyisoprene (cis-PI) melts with the EMSIPON (Engine for Mescoscopic Simulations for Polymer Networks) code that has been developed in the Computational Materials Science and Engineering group at the National Technical University of Athens. The code implements a hybrid particle-field Brownian dynamics/kinetic Monte Carlo method advanced in the course of the last four years. Structural, thermodynamic and rheological properties have been computed and are compared with the corresponding properties of monodisperse cis-PI melts at the same temperature. Moreover, the algorithm employed for creating initial configurations of bidisperse as well as polydisperse polymer melts is explained. [ABSTRACT FROM AUTHOR]

This study concerns atomistic simulations of dopamine in a fully hydrated lipid bilayer consisting of dipalmitoylphosphatidylcholine (DPPC) molecules. To be more specific, molecular dynamics and umbrella sampling simulations are performed for the detailed investigation of how dopamine behaves in the lipid phase. The latter simulations aim at the computation of the potential of mean force of dopamine from the lipid to the aqueous phase along the normal to the two leaflets of the membrane. From such simulations, useful thermodynamic quantities may be calculated. As far as the molecular dynamics simulations are concerned, the dopamine molecule is initially placed in the water phase, and the time evolution of the whole system under consideration is studied in terms of selected properties, such as various mass density profiles and the existence of hydrogen bonding between dopamine and the other molecules of the simulated system. [ABSTRACT FROM AUTHOR]

The mathematical modeling of heat and mass transfer of moisture and gas in capillary-porous space of the solid biofuel, which are the theoretical basis for the development of technologies of enrichment of biofuels, comprising heating with simultaneous saturation of the capillary-porous space of the synthesis gas and the combustible components of the recirculated gas that promotes complete combustion of the elements and enhances fuel efficiency and environmental friendliness of the boiler plant. A mathematical model that determines the kinetics of the heart's humidity regime and biofuel cell saturation is given and discussed. Expressions are given for calculating the necessary parameters of the fuel pellet. [ABSTRACT FROM AUTHOR]

NASA has selected eight postures of the human body and studied the corresponding mass-inertial characteristics for them based on data for male astronauts. Due to the deficiency of such data for female astronauts they do not report data for females. That is why in the current article we present results for two of these basic positions for females. Recently we have performed a 3D mathematical study for the characteristics based on anthropological data for Bulgarian males and observed that our results are closed to those reported for the male astronauts. Our study for the mass-inertial characteristics for females is based on data for about 2854 Bulgarian women. More specifically, we present results for the so-called standing and weightless (relaxed) positions. We determine the position of center of mass and principal moments of inertia of the female body in the specified positions using a 16-segmental biomechanical mathematical model that has been also generated within SolidWorks environment. We verify the computer model by comparing analytical results for each of the body segments with the results achieved using the CAD realization. We calculate the characteristics of the average Bulgarian woman and then find inertial parameters of this "average" female in the above mentioned body positions. In principle, our approach can be conveniently used to calculate the mass inertial data also for any particular female individual provided that the anthropometric set of parameters for that individual are measured. The model we used is appropriate when one needs such parameters in problems appearing not only in space exploration with the participation of female astronauts, but also in rehabilitation, sport, criminology, robotics, etc. [ABSTRACT FROM AUTHOR]

The strain gradient elasticity theory (SGET) introduces the microstructure to the constitutive equations to explain the material size effects. The constitutive equations of the SGET appear a boundary layer [1, 2]. The interior penalty discontinuous Galerkin finite element method (IPDGFEM) is suitable to handle the boundary layer and the mesh design as well as vary the polynomial degree in the local basis functions. This research objective centers on carrying out an a posteriori error analysis for the (symmetric) IPDGFEM of a general problem of the SGET in 2D. [ABSTRACT FROM AUTHOR]

This article considers mathematical model of jumping solid system with variable mass internal mover. The model is coupled with inverted pendulum model. System control parameters are proposed. [ABSTRACT FROM AUTHOR]

We study a model of a critical fluid described by the standard φ4 Ginzburg-Landau Hamiltonian and determine the Casimir force in the case of Dirichlet-Dirichlet boundary conditions imposed along the finite dimension of the film. Physically, the fluid can be a simple fluid near its liquid-vapor critical point, or a binary liquid mixture close to the corresponding demixing point. Mathematically, the stable states of the system are determined by the minimizers of the functional which leads to finding the solution of the corresponding Euler-Lagrange nonlinear differential equations under the considered boundary conditions. We solve these equations in terms of Weierstrass and Jacobi elliptic functions and give analytic representation of the Casimir force as a function of both the temperature and ordering field. The derived expressions are then evaluated numerically in the plane of the temperature and the ordering external field. [ABSTRACT FROM AUTHOR]

The problem of illicit discharges in the sewer system influence the quality of wastewater acts both on the proper functioning of the sewer system, on the wastewater treatment plant (WWTP) and on the receiving water body in case of combined sewer overflow (CSO) activation. The implementation of a chemical monitoring network is necessary to promptly detect the event of contamination. The installation and maintenance costs can be reduced by optimizing the position of the sensors so obtaining, at the same time, a reliable and cheap monitoring infrastructure. In this study, it is proposed a Bayesian probabilistic approach to the positioning of water quality sensors in urban drainage networks to detect the illicit intrusion in dry and wet weather, comparing the results. The methodology is applied on the literature scheme from the Storm Water Management Model (SWMM) manual, Example 8. [ABSTRACT FROM AUTHOR]

This note presents a feasibility study of using a shallow neural network to compute attitude controller gains for satellite attitude maneuvers actuated by reaction wheels. The conventional solution proposed for the widely-used Lyapunov-based PD attitude controller gains ceases to be near time-optimal when the reaction wheels' performance constraints are reached. Thus, for applications, whose success is sensitive to how fast the maneuvers are performed, it becomes advisable to use different gain values for different maneuver angles. We propose a method of calculating optimal and sub-optimal gains and train a neural network, which can be used on board of a nanospacecraft with limited computational resources to compute the controller gains for any given maneuver. Our numerical experiments corroborate that the gains learned by the neural network outperform those obtained from the conventional solution. [ABSTRACT FROM AUTHOR]

The present study aimed to analyze the self-esteem (SE) throughout SE statements as well as overall SE in people with physical disabilities (PD) using assistive technologies (ATs) and compare the SE between people with PD who regularly participating in sport and who not participating in any sport in their leisure. Two groups of people with PD (n=132) according to the type of ATs usage were recruited for the study: (1) those who use for their daily mobility (DM) ATs like electronic and manual wheelchairs (participating in sport, n=39; not participating in sport, n=46) and (2) those who for their DM use other types of ATs like walkers, sticks, crutches, etc. also (participating in sport, n=23; not participating in sport, n=24). The Rosenberg Self-Esteem Scale to analyze the SE among evaluated groups of people with PD was used as a primary research method. Significantly higher overall SE was shown by the groups of people with PDs - wheelchair users, as well as other ATs users - who are regularly participating in sport, compared to those who are not participating in any sport in their leisure. The group of wheelchair technology users, as well as other ATs users who do not participate in sport, showed a significantly higher level of negative feelings about themselves compare to those who regularly participate in sport in their leisure. The group of wheelchair technology users who regularly participated in sport in their leisure presented a significantly higher level of positive feelings about themselves than wheelchair technology users who did not participate in sport leisure activities. ATs usage should significantly help increase overall SE as well as positive SE in people with PDs at the same time with regular sports participation in this minority society groups' leisure time. [ABSTRACT FROM AUTHOR]

We present a finite element code, which was developed to perform simulations based on self-consistent field theory considering three-dimensional domains of arbitrary geometry. The aim is to address systems comprising polymer melts in contact with solid surfaces and study their interfacial properties. The code solves the Edwards diffusion equation for both matrix and grafted (to the solid surface) chains by applying the appropriate initial and boundary conditions. Our approach for inserting the grafted chains does not require any smearing across the tangential directions to the solid substrate. Convergence is achieved by means of a simple mixing iterative scheme with respect to the self-consistent field. Bonded interactions along the polymer chain are described by the continuous Gaussian chain model. Considering a compressible polymer melt, the nonbonded interactions amongst polymer segments are calculated via Helfand's equation. All simulations are performed in the grand canonical ensemble. [ABSTRACT FROM AUTHOR]

This article deals with the creation of model characteristics of the female pole vault jumpers. Pole vault is the only athletic event in which the performance is reached with use of tool. The pole use puts this event away from fundamental locomotion and adjoins it to complex athletic disciplines. The movement activity is realized in two basic parts; the first is approach ended with take-off and the second is the movement of jumper on the pole. This research was performed in on the meetings Golden spiked shoes in Ostrava, Czech Republic. We got our kinematic variables by analyser Consport Motion Analysis System (CMAS). We were working with 19 female jumpers their sport performance level was 380 - 483 cm (S). For needs of this research we divided them in two smaller groups, lover performance level group (S1) and higher performance level group (S2). The detailed kinematic analysis enabled us to know the movement activity of the female pole vault jumpers and to determine the decisive kinematic parameters. From the selected parameters we created two models for the sport performance levels of 380 - 430 cm and 440 - 483 cm, which we used for the comparative analysis of the monitored Slovak female recorder in the pole vault. [ABSTRACT FROM AUTHOR]

A transient contact problem with moving boundaries for a thin elastic cylindrical shell and a rigid indenter bounded by a smooth convex surface is considered. The shell model is formulated as a 2D constrained continuum on the background of a general higher-order shell theory A closed mathematical formulation is given and a system of resolving equations is constructed. The solution to the problem of the transient function for the cylindrical shell is obtained. An algorithm for solving the spatial transient contact problem for an infinitely long cylindrical shell and absolutely rigid indenter in the case of a normal impact on the side surface of the shell is developed and implemented. [ABSTRACT FROM AUTHOR]

Objective: The objective of the present study was to verify the flat foot prevalence in Slovak preschool children by using the plantographic analysis. Methods: 210 healthy preschool children aged 4 to 6 years underwent podographic analysis by podoscope device. The plantograms were evaluated by Chippaux-Smirak indexing method. Probands were assigned to 4 groups based on flatness level. Results: The prevalence of flat foot deformity was 24% for the 1st level, 28% for the 2nd level, and 25% for the 3rd level of flat foot. 23% of children had no sign of foot flatness. Girls were affected less with the ratio of 1:1.3 girls to boys. Conclusions: The outcome indicates the significant occurrence of flat foot. All three stages of flat foot were present and the majority of probands were assigned to the second level flatness category. We recommend using the modern plantographic methodology for early flat food diagnostics based on its low time-consuming character, objectivity, and smart data storing possibility. The assessment method requires low psychological load for probands, it is painless and simple in nature. [ABSTRACT FROM AUTHOR]

The comparison of selected kinematic parameters in the competitive motor activity in two horizontal athletic jumping events (long jump and triple jump) and two vertical ones (high jump and pole vault) were used to highlight a number of common features, as well as the specific features and hallmarks of its implementation in each of these events. The differences result from the efforts to create optimal conditions for the realization of key phases of motor activity - the link between the approach and take-off. [ABSTRACT FROM AUTHOR]

The article is devoted to the development of the asymptotic averaging method for nonlinear equations of the theory of elasticity and the deformational theory of plasticity used to calculate the effective mechanical characteristics of the materials described by these equations. Based on this method, an algorithm is formulated for calculating a nonlinear diagram of effective rigidity depending on the stress-strain state for a composite material, and a radial multipliers method for effective solution of the problem on a cell with multilayer inclusions of spherical and cylindrical shape. [ABSTRACT FROM AUTHOR]

This paper discusses a finite element approach of modeling the wake-induced vibrations of the bundle conductors in transmission lines. An aeroelastic system consisting of two bundle conductors connected at intervals by spacers is considered. The wake coupling between subconductors is modeled with the modified Simpson's theory. Deflection of an oscillating conductor from the straight line connecting a finite element ends is assumed to be small as compared with the element length; as a result the element tension can be estimated approximately as a constant as well as the tensile strain. The dependence of the strain on the transverse displacements is defined by the quadratic approximation. The coefficients of expansions of the element displacements and twisting angle in sine series with integer number of loops per element length are considered as generalized coordinates as well as their values at end points. The equations of motion of the conductor with nonlinear elastic, inertial and aerodynamic forces are formulated in the generalized coordinates, and the appropriate linearized equations for small aeroelastic oscillations around the static equilibrium position are derived. The latter equations allow one to determine the critical speed of the conductor flutter. Finally, bundled conductors' susceptibility to wake-induced vibrations is illustrated on an exemplary twin- bundle, three-subspan model. Effects of bundle parameters and the means to account them when applying the approach are discussed. [ABSTRACT FROM AUTHOR]

New incremental formulation of the compatibility equations for two-phase shape memory alloys is obtained on the basis of the once coupled constitutive model, the boundary value problem for small increments of stresses and phase volume ratio is proposed, and two stability concepts required to formulate linearized buckling problems for shape memory alloys are presented. [ABSTRACT FROM AUTHOR]

An attitude dynamics of a satellite with a variable properties of inertia under the central of gravity is analyzed. One assumes that the satellite is equipped by rotors with a variable kinetic moments. We suppose that the satellite mass center moves staying in a Keplerian elliptic orbit. We find special rules for the mass distribution change such that relative equilibria prescribed in advance exist. For these relative equilibria necessary conditions of stability are analysed. [ABSTRACT FROM AUTHOR]

It is proposed applications of the theory of combined dry friction [1-10] in the problem of the ball rolling on boundaries of two identical frames. Father development of this model can be used in investigation of the dynamic of the a so-called "Butterfly" robot, consisting of two identical shaped plates rigidly placed parallel to each other on a small distance aimed at manipulating a ball that can freely roll on the plates' boundaries as on rails [11]. The friction force and torque are computed by the integration over the contact area so that the exact dynamically coupled integral model accounting the relationship of all the components of friction is obtained. This exact model is replaced by approximated analytical model [10] which is completely satisfy to all analytical properties of integral model as function kinematics parameters without increasing the number of coefficients. [ABSTRACT FROM AUTHOR]

Nowadays cities are subjected to an urbanization increase, such phenomena has several consequences that affect different topics but especially regard urban mobility, because of this increase the number of people using cars rises consequently congestion and CO2 emissions increase. The rise of private vehicles circulating creates a decrease of average speed travel that affect the entire city context so its liveability, then when a high number of vehicles moves into infrastructure that was not designed for that capacity probability of collision will increase due to the elevated interaction compromising people safety. For this reasons public transport systems represents a key role in the liveability of a city because most of them operates in reserved areas and moreover decrease the number of private vehicles moving in cities. The progress that automotive was subjected to affected also urban mobility, first of all the innovation that mainly involved public transport regarded the use of electric vehicles instead of fossil fuels ones, that had a significant environmental impact on bus public transport systems that used fossil fuels vehicles. Anyway the most important innovation that in the last decade is involving automotive regards autonomous vehicles (AVs), these new technologies represent an important change for public transport efficiency due to the elevated performance so the relevant reduction of human mistakes, then because of the high precision of headways would provide a high quality service. Taking into account that each public transport systems has its own characteristics in relation to vehicles type and configuration, the introduction of autonomous vehicles requires specific adjustments and changes. [ABSTRACT FROM AUTHOR]

The improvements made over the years in automotive transportation field are significant, between them the most relevant is the one related to autonomous vehicles (CAVs) and regards several aspects as performance, comfort, low emission but especially safety. Such aspect represents the one that mostly motivated research studies because according to international data roadway accidents is among the first ten causes of death in the world, in order to outline the importance of this problem it can be considered that every year all over the world roadway incidents cause between 20 and 50 millions of injured people wich from an economical point of view costs at least to an amount corresponding to 90% of global GDP (gross domestic product). In most cases the reason that causes an accident is human mistakes, that is why it is useful to equipe vehicles technologies and systems so to achieve the goal of correct as much as possible human mistakes. It is expected that since 2035 there will be a quantity of autonomous vehicles of 75% then the economic impact on automotive sector since 2030 is expected to be around 71 billion with a global market of 44 million vehicles. [ABSTRACT FROM AUTHOR]

Civil Infrastructures regardless sector they belong to as hydraulic (dams, pipelines), transport (bridges, roadways) or building represent a fundamental element for our lives quality and improvements then considering the continuous technological progress, existing infrastructures have to be adjusted in order to cohabit with innovations or to be complementary to new constructions. For these reasons it is important to guarantee their complete efficiency with correct maintenance operations but especially monitoring ones so to forecast imminent damages, considering that during its life cycle a generic infrastructure is subjected to dynamic and various loads, deterioration of materials and atmospheric agents that can compromise its functionality. Such aspects result fundamental considering that in many developed countries as Europe most of existing bridges were realized in world war two decades, then for example in USA 70% of roads and bridges was realized before 1930s while in Japan majority of bridges was built in 1970s. Nowadays technologies used for monitoring interventions or inspections are several but most of them are intrusive and require the need of certified human operators, these aspects create a significant safe risk and cost increase both for operators payment and equipment, then the service that an infrastructure has to provide is compromised as for example traffic interruption for bridges. In last decades to solve critical issues due to operators cost and safety or services interruption, UAVs (Unmanned Aerial Vehicles) commonly known as drones were used for monitoring operations, such systems have several advantages mostly because they are not intrusive and do not require a human operator. For these reasons especially due to cost reductions, UAVs for civil engineering infrastructure are expected to reach €40 billion market worth in next decade. [ABSTRACT FROM AUTHOR]

Design phases of any type of infrastructure need the intervention of several techniques and professionals figures in order to achieve an optimal efficiency during realization phases and then for the infrastructure life cycle, considering that in such contexts there is a cooperation of several figures it is important to facilitate and speed up operations regarding creation of models, calculation and files information sharing. In order to meet these needs it was implemented the so called BIM, a new method that allows software interoperability and integration among various processes, BIM's acronym stands for "Building Information Modeling" and it is defined as a "digital representation of physical and functional characteristics of an object". Thanks to such model it is possible to integrate data of different aspects (structural, architectural, management, energy) realizing a model that is characterized by all useful information as dimensions, materials or costs that will not be lost or divided during file transfer. These skills allowed BIM to spread quickly, especially for advantages linked to better costs and times management so that benefits involves also the reduction of CO2 emissions in fact to promote such objective many countries as Norway, USA, Singapore and UK have incentivized BIM use for AECO (Architecture, Engineering, Construction, Owner and Operator) industry aiming to reduce 80% of emissions in 2050. The use of BIM for infrastructure has a positive and important trend so that it is starting to be introduced also in countries legislation as a fundamental design criteria, and in future it is expected to become mandatory. [ABSTRACT FROM AUTHOR]

The aim of this study is to apply Computational Fluid Dynamics (CFD) to optimize the contact tanks used for the disinfection process within water treatment plants. Numerous studies have shown that by changing the geometric characteristics of traditional "serpentine" tanks used for disinfection, it is possible to reduce short circuits and the development of low speed areas. These construction measures can therefore bring the flow closer to the ideal plug-flow condition and increase the disinfection efficiency. In particular, this study reports on results from Large Eddy Simulation (LES) used to simulate three-dimensional turbulent flow and disinfectant transport in different contact tanks, suggesting that the tank and baffle's geometry can significantly influence the process. [ABSTRACT FROM AUTHOR]

In recent decades, the changing scenario in the availability and the use of water has made the efficiency of water distribution systems (WDSs) management a topic of great importance, particularly in terms of leakage detection and control. The definition of the relationships, which relates the leak outflow and the relevant hydraulic parameters has received more and more increasing attention in literature. Here, the attention is mainly focused on the analysis of the behavior of different types of leak openings in pressurized pipes, taking into account the effect of rigid and deformable materials. [ABSTRACT FROM AUTHOR]

Populations documenting to date low incidence rates of SARS-CoV-2 infection are immunologically susceptible and at high exposure risk of new COVID-19 outbreaks during phase 3 of the pandemic. Following the experience documented by other countries with regard to the use of Information Communication Technology (ICT) to counteract the current pandemic, Italy has implemented a contact tracing system based on a mobile application. In this work, we describe the proposal of a complementary ICT-based prototypal model of COVID-19 prevention and surveillance system, involving the university students as sentinels acting both in the academic community and the general population. [ABSTRACT FROM AUTHOR]

In Italy more than 7 Mtons of organic solid waste are generated each year, on average 117.29 kg/hab.year The eating habits of the Italian population was studied to identify the most consumed foods. The most consumed foods were used to prepare a representative sample of food waste. Two methods were used to estimate the bio-methane production potential. The first method, calculate the bio-methane production potential based on the concentrations of lipids, carbohydrates and proteins, the second method use the results of the elemental analysis. The characterization results showed a potential for generating bio-methane of 219 ml.CH4/g for method 1 and 534 ml.CH4/gSV for method 2. Considering the generation of food waste in Italy and the potential for bio-methane production results show that it would be possible to produce 1,543.x 106 and 3,092 x 106 m3CH4 for method 1 and 2 respectively and thus For the method 1, it is possible to recovery equivalent energy 50,942 TJ/year and 102,044 TJ/year for method 2. [ABSTRACT FROM AUTHOR]

Almond shells represent an abundant agricultural waste which is annually produced in Sicily. Pyrolysis and gasification can be adopted to successfully modify its morphological and structural properties to produce graphitized porous material than can be used for environmental and energetical applications. The increase in pyrolysis and activation temperature led to pores formation and widening on the external surface as well as a re-organization of the internal structure toward a more graphitic one. Reaction temperatures tested were in the range of 600 °C to 1,000 °C, with 100 °C step increase, and the obtained material was characterized through SEM analysis. The samples prepared at 800 °C and 1,000 °C were further studied through TEM investigation. Aside from pore widening, as long as activation temperature was raised nano-onion carbon formations, characteristics or more graphitic structure were observed. [ABSTRACT FROM AUTHOR]

Pistachio shell waste was treated via slow pyrolysis using a fixed bed horizontal lab scale pyrolyzer to evaluate the possibility to product high energy dense solid biofuel and/or a valuable carbonaceous material for advanced applications. Pistachio shells, obtained from a fruit processing industry located in Catania, Sicily, were pyrolyzed with flowing nitrogen (150 ml/min) at 200, 250, 315 400 and 500 °C for 0.5 hours. Pyrolysis products, solid, liquid and gas fractions were characterized in terms of mass yields, while raw material and biochars were characterized via thermogravimetric and calorimetric analysis to evaluate proximate analysis and high heating values (HHV) respectively. Results showed that, on a dry basis, solid mass yields, on a dry basis, varied between 98 and 25% at 200 and 500 °C respectively, while liquid yields increased up to 48% at 500 °C. HHV of solid residues increased with temperature up to 31.3 MJ/kg at 500 °C but with a sharp increase between 250 and 315 °C showing values of 21.4 and 26.9 MJ/kg respectively. [ABSTRACT FROM AUTHOR]

A certain level of statistical literacy is regarded as baseline, and it is used by the people to orientate in the sheer amount of information that they face. The aim of this paper is to analyze the level of statistical literacy in future teachers, which has been determined based on a test with a number of tasks consisting of task solution, chart reading etc. The results of quantitative research implemented through a questionnaire showed a very low level of statistical literacy among the teacher prep students, with high school graduation and interest in statistics being the most important predictors. [ABSTRACT FROM AUTHOR]

In the water distribution networks, a deliberate or accidental contamination causes loss of water quality; the implementation of a real-time sensor network is essential to promptly detect the event of contamination. To achieve the optimum positioning of the probes, to reduce the cost of the instrumentation and maintenance, and obtaining, at the same time, a reliable monitoring of the system, optimization techniques are widely applied. In the present study, a numerical optimization approach was compared with the results of an experimental campaign. The optimization problem is formulated in accordance with literature state-of-the-art, using the genetic algorithm NSGA-II coupled with a hydraulic simulator. The results were tested and verified using a looped laboratory distribution network, equipped with a real-time monitoring water quality system, which allows to run contamination experiments in a controlled environment. [ABSTRACT FROM AUTHOR]

The current European environmental strategy is committed to sustainable development by generating action plans to improve the environmental performance of products and services. The analysis of carbon footprints (CFP) is considered one such. One methodology to quantify the CFP is the Life-Cycle Assessment. (LCA) is an environmental management tool that evaluates the environmental performance of a service or a product using evaluation of emissions and consumption of resources at every stage of the life cycle, "from cradle to grave". The aim of the study is to evaluate the total greenhouse gas (GHG) emissions associated with the life cycle of potable water supplied from a water supply system. This study highlights an operational tool to help the water manager to improve the current environmental management of the system, considering only the system operating phase. The methodology proposed was applied to a real case study, a complex water supply system, the Favara di Burgio system (Sicily, Italy). [ABSTRACT FROM AUTHOR]

The mobility scenarios have been modified by the COVID-19 pandemic. Catastrophic and health events cause strong repercussions on daily activities and related mobility habits. In Italy, as in other contexts, we have witnessed a period of lockdown that has led to an almost zero travel. This work shows an overview of the changes in mobility choices before and after the COVID-19, with particular attention to sustainable forms of mobility such as shared mobility. It can reduce the use of private vehicles if properly incentivized and can be enhanced within the different forms of urban mobility, adopting ad hoc strategies and encouraging the active participation of the population in the assessment of critical issues and solutions towards sustainability. First results, analyzed at national level, provide a basis for future research steps on the assessment of the perceived safety by users in the use of different forms of mobility before and after the pandemic. [ABSTRACT FROM AUTHOR]

The structure of urban transportation and mobility is dramatically changing, partly due to the explosive growth in shared-use modes (SUM) of travel such as bikesharing, carsharing and, more recently, electronic (e-)scooter/ monowheels - sharing. Municipal transport planners and policymakers are struggling to both understand and manage their potential impacts. Developing, adopting and enforcing regulations that aim to maximize transportation options while simultaneously ensuring public safety and the public good is proving to be a challenging task in such a time of fast evolution. According to the Italian regulations, electric scooters, hoverboards, segways and monowheels are allowed to circulate in urban areas, pedestrian/cycle paths and roads with a speed limit of 30 km/h. This study aims to select the suitable paths for the circulation of electric scooters, hoverboards, segways and monowheels within the municipal territory of Catania, applying Multi-Criteria Decision Aid approach. [ABSTRACT FROM AUTHOR]

Nowadays, cities are increasingly required to be smart, sustainable, resilient and adaptive and, particularly following the COVID-19 pandemic, an integrated approach to transport planning needs to be adopted. In fact, European policies have adopted a series of limitations in the transport sector that led the scientific community to put into question the traditional transport planning process, by accelerating processes close to sustainability, started some time ago. In fact, many efforts in terms of strategies, initiatives and research have been made in the last decade to enhance new forms of sustainable urban mobility, in order to reduce the externalities associated with the transport sector. To achieve this goal, the European Commission has emphasized the integrated planning at all mobility levels. Among the other instruments, it has been identified a key role in the writing of the Sustainable Urban Mobility Plan (SUMP), its management and also through Intelligent Transport Systems (ITS). Based on this premise, the aim of this paper is to present first results of a wider research aimed at investigating the methodological and practical approaches to boost the strategy of integration between transport systems and urban planning by using ITS technologies and infomobility systems. The research can support further investigations in order to define specific Key Performance Indicators (KPIs) to measure and monitoring the impacts of technologies on developing smart cities and promoting sustainable mobility approaches, facing the urban planning and transport mobility issues of modern society. [ABSTRACT FROM AUTHOR]

The Machine Learning method Random Forests Regression is used to predict the Gamma index passing rate percentage of radiosurgery therapy plans. A software application that evaluates the output data is developed by the aid of the scikit-learn library of the Python programming language. The regression model contains four independent variables that are parameters of the plans - monitor units, normalization point, dose per fraction and planning target volume. The dependent variable is the Gamma passing rate that has to be predicted. It was found that the planning target volume is the variable with the biggest importance, and that monitor units is the variable which is second by importance. The model predicts the Gamma passing rate with an average accuracy greater than 97%. The accuracy of prediction increases when the planning target volumes are bigger. [ABSTRACT FROM AUTHOR]

Semi-analytical corrections for the unsteady downwash and enhanced approximate expressions for the indicial lift of thin wings in the subsonic regime are presented in this study. Lifting-line and acoustic theories form the basis of the method, within an effective synthesis of the governing physics. The unsteady flow perturbation consists of a step-change in angle of attack or a vertical sharp-edged gust. The proposed model is successfully evaluated against literature results for rectangular swept wings. [ABSTRACT FROM AUTHOR]

As urban systems in Europe were mostly designed before the event of cars and then used with them, today general concern about possibility to implement more pedestrian and alternative transport system is highly slowed if not blocked by difficult on site situations that make it problematic to adapt today's network to more non-only car transport. The topic of the research is to understand the perceived importance of adaptation of some paths to non-car transport, based on values given to ease of use, safety, beauty of built and green environment and characteristics of terrain. Some possible path will be individuated to verify the results on site. [ABSTRACT FROM AUTHOR]

The rapidly increasing transport in the last decades, characterized by high motorization rate especially in urban areas, constitutes a relevant contemporary issue addressed by scholars, planners and policy-makers, aiming to promote sustainable mobility. Nowadays, the COVID-19 crisis has influencing transport behaviour with a massive blow to public transport (PT) due to the social distancing. In this context, solutions represented by Demand Responsive Transport (DRT) can play a fundamental role not only in weak demand areas but also where the use of PT is relevant, as on-demand shuttles allow for more physical distancing and are cost-effective for more frequent routes. An essential point of the proposed study to be highlighted is the design of a structured multi-layered survey to identify the core attributes and the fundamental variables connected to the acceptance and potential use of a DRT service. The case study of a Mediterranean University has been analyzed, which is considering the opportunity to implement a public on-demand transport system, in order to enhance the efficiency of the current traditional public transport service and to discourage the use of the private vehicle. First results of an in-depth investigation are presented, which will serve to explore transport demand preferences towards flexible mobility and to identify the characteristics of the DRT service to be implemented. This work also lays the basis for further research with the aim of investigating the key aspects connected to innovative shared mobility solutions and thus supporting policy-makers and public and private transport companies to face new mobility issues. [ABSTRACT FROM AUTHOR]

The process of hemolysis of erythrocyte suspension induced by hydrochloric acid (HCl) is investigated by measuring the UV-Vis absorption spectrum in the range 250 nm - 750 nm at interval 1 nm. The spectrum is measured each 15 s which permitted to follow the changes in absorbance at different wavelengths during hemolysis. The kinetics of the hemolysis is monitored by the changes in the absorbance at 700 nm, and by the changes in the wavelength of the main absorbance peak in the spectrum due to the hemoglobin. Because of the finite number and discrete values of the wavelengths used in the measurement the real value of the peak wavelengths in the spectra must be found by additional processing of the experimental data. The procedure uses the first derivative of the spectrum (dA/dt) and a geometrical approach to calculate the value of the wavelength at which the first derivative dA/dt is equal to 0. The procedure smoothed the kinetic curve of the peak wavelength to a great extent. This permit to compare it to the curve of the absorbance at 700 nm and to make assumptions of the process that occurs during the acid hemolysis. The procedure could be applied to any process where there is a shift in the peaks' wavelength. [ABSTRACT FROM AUTHOR]

The redox reaction of hemoglobin (Hb) is studied by spectroelectrochemistry. Fifteen absorption spectra are measured at different electrode potentials in the range from +0.4 V to -0.3 V. The spectra are collected in a matrix, X, with each spectrum representing one column. The method of Principal component analysis (PCA) is applied by the aid of the scikit library of the Python programing language. X is decomposed and presented as the matrix multiplication product of two matrices, the Scores matrix, S, and the Loadings matrix, L. In such presentation S contains the "abstract" spectra of the principal components (PC), and L contains the coefficients used to reconstruct all original spectra as linear combinations of the PC. The results show that the original spectra can be presented as combination of two PC. The Loading values of the two components can be directly used to estimate the ratio of the oxidized to the reduced form of Hb in each spectrum and to construct the Nernst plot of the redox reaction. Two Nernst plot were obtained, one for each PC. The redox potentials estimated from these plots differ by only ±2.5 mV from the value obtained by the original absorbances, and the slopes coincide to 98.82% for the first PC and to 99.88% for the second PC. [ABSTRACT FROM AUTHOR]

The evolution of cities must not ignore the needs of specific population groups that need more help. In this way, urban development (such as the definition of SUMP) must consider the aspect of accessibility also through a participatory comparison with population groups that more than others can testify to their impediments during normal travel activities in the city. The research has focused on the calibration of a questionnaire and on the administration to a selected sample of users with motor disabilities by investigating, through the Likert judgement scales, the criticalities related to 3 elements present in urban spaces near road intersections: the sidewalk, the ramp and the traffic light. Through a statistical analysis, the judgements of two different groups of people with disabilities (wheelchair and walking stick/walker) have been compared and it was possible to compare the critical points, arriving at some useful considerations for the mitigation of impacts This work lays the foundations for a more in-depth investigation and the possible application of a transversal analysis to the same sample in the coming months, useful to evaluate how the vision of the problem has changed and at the same time to provide local administrations with some tools to evaluate the procedures for the removal of architectural barriers related to the elements analysed. [ABSTRACT FROM AUTHOR]