Hydrodynamic limit for a diffusive system with boundary conditions

We study the hydrodynamic limit for the isothermal dynamics of an anharmonic chain under hyperbolic space-time scaling and with nonvanishing viscosity. The temperature is kept constant by a contact with a heat bath, realised via a stochastic momentum-preserving noise added to the dynamics. The noise is designed so it contributes to the macroscopic limit. Dirichlet boundary conditions are also considered: one end of the chain is kept fixed, while a time-varying tension is applied to the other end. Moreover, Neumann boundary conditions are added in such a way that the system produces the correct thermodynamic entropy in the macroscopic limit. We show that the volume stretch and momentum converge (in an appropriate sense) to a smooth solution of a system of parabolic conservation laws (isothermal Navier-Stokes equations in Lagrangian coordinates) with boundary conditions. Finally, changing the external tension allows us to define thermodynamic isothermal transformations between equilibrium states. We use this to deduce the first and the second law of Thermodynamics for our model

A Precious Documentary Heritage: the Archdiocese Archive of Bologna (Italy)

This contribution wants to show the history of the Archivio Arcivescovile in Bologna also to an untrained public: the numerous, important documents that it contains, the people who worked on it, the changes of seat that took place over the centuries. In this way, introducing the many funds now preserved, a history very linked to the Bolognese territory is rediscovered: in fact ancient and recent papers housed in this place often transmit unexpected, surprising information and contribute to a deeper knowledge of many places (sacred and profane) that cheer the gaze of the yesterday and today traveller

Tolkien’s Lore: The Songs of Middle-earth

Examines and categorizes the over sixty examples of folk-songs and poems in Middle-earth—songs of lore, ballads, ballad-style, and nonsense songs

Art as Storytelling: A Process of Discovery and Creativity Applied in the Medium of Story Branding

Storytelling finds its purpose in the origins of humanity. The advent of technology, hardware, and software has created an intersection of ubiquity of storytelling opportunity and scarcity of storytelling ability. For this reason, the storyteller needs to be “enlightened”. This thesis presents a comprehensive storytelling process that equips the storyteller to turn words into artistic expressions, specifically in the artistic medium of branding. Through story branding, artistic pieces that tell stories are branded through multiple techniques that spread the story’s idea through an entire population

cartOut. Cardboard architecture 4 climate challange.

Our cities suffer from the urban heat island phenomenon, in which climate change is reflected and amplified. Becoming aware of this and understanding how it is happening is necessary for developing a strategy to curb the problem. Cardboard is an ancient material that has only recently been used in architecture. Today it is being rediscovered as a versatile material that can be worked quickly via digital technologies. The algorithmic study of geometries and automated processing present many avenues of research. Today’s computational power allows us to insert and verify different geometries in realistic contexts in which the microclimate and its effects can be investigated. In architecture, the use of cardboard has always implied a technological challenge in improving construction techniques to allow for temporary and permanent constructions. Architects have been interested in using this semi-finished material given its unique characteristics. It is a light, versatile material that can yield various construction solutions through the use of different techniques. Its durability has been improved over time while maintaining a low impact on the environment due to its renewable life cycle. Today, using cardboard outdoors means solving various technological problems in an innovative way while respecting the environment and architecture has thus responded to climate change through sustainable production and realization. The aim of this research is to use cardboard to create outdoor elements capable of controlling the microclimate in built areas. The studies made have shown how effective geometry can be in controlling the microclimate. Regenerating outdoor spaces through the use of geometrically designed cardboard elements regenerates and enriches the heritage and acting on the factors that affect comfort means improving the quality of the outdoor environment. Improving the usability of outdoor spaces is even more important in light of the ongoing pandemic, due to which outdoor spaces have gained new importance in conducting social activities

Hydrodynamic Limits and Clausius inequality for Isothermal Non-linear Elastodynamics with Boundary Tension

We consider a chain of particles connected by an-harmonic springs, with a boundary force (tension) acting on the last particle, while the first particle is kept pinned at a point. The particles are in contact with stochastic heat baths, whose action on the dynamics conserves the volume and the momentum, while energy is exchanged with the heat baths in such way that, in equilibrium, the system is at a given temperature T. We study the space empirical profiles of volume stretch and momentum under hyperbolic rescaling of space and time as the size of the system growth to be infinite, with the boundary tension changing slowly in the macroscopic time scale. We prove that the probability distributions of these profiles concentrate on L^2-valued weak solutions of the isothermal Euler equations (i.e. the non-linear wave equation, also called p-system), satisfying the boundary conditions imposed by the microscopic dynamics. Furthermore, the weak solutions obtained satisfy the Clausius inequality between the work done by the boundary force and the change of the total free energy in the system. This result includes the shock regime of the system

Hydrodynamic Limit for an Anharmonic Chain under Boundary Tension

We study the hydrodynamic limit for the isothermal dynamics of an anharmonic chain under hyperbolic space-time scaling under varying tension. The temperature is kept constant by a contact with a heat bath, realised via a stochastic momentum-preserving noise added to the dynamics. The noise is designed to be large at the microscopic level, but vanishing in the macroscopic scale. Boundary conditions are also considered: one end of the chain is kept fixed, while a time-varying tension is applied to the other end. We show that the volume stretch and momentum converge (in an appropriate sense) to a weak solution of a system of hyperbolic conservation laws (isothermal Euler equations in Lagrangian coordinates) with boundary conditions. This result includes the shock regime of the system. This is proven by adapting the theory of compensated compactness to a stochastic setting, as developed by J. Fritz in \cite{Fritz1} for thesame model without boundary conditions. Finally, changing the external tension allows us to define thermodynamic isothermal transformations between equilibrium states. We use this to deduce the first and the second principle of Thermodynamics for our model

The Effects of Music on Maximal Anaerobic Performance

Undergraduate Applie