L'importanza del coefficiente di asimmetria nella regionalizzazione delle piogge intense in toscana

Metodo G e Radic

Performance evaluation of an open distributed platform for realistic traffic generation

Network researchers have dedicated a notable part of their efforts to the area of modeling traffic and to the implementation of efficient traffic generators. We feel that there is a strong demand for traffic generators capable to reproduce realistic traffic patterns according to theoretical models and at the same time with high performance. This work presents an open distributed platform for traffic generation that we called distributed internet traffic generator (D-ITG), capable of producing traffic (network, transport and application layer) at packet level and of accurately replicating appropriate stochastic processes for both inter departure time (IDT) and packet size (PS) random variables. We implemented two different versions of our distributed generator. In the first one, a log server is in charge of recording the information transmitted by senders and receivers and these communications are based either on TCP or UDP. In the other one, senders and receivers make use of the MPI library. In this work a complete performance comparison among the centralized version and the two distributed versions of D-ITG is presented

EUROPEAN MIGRATION POLICIES BETWEEN RESTRICTIONS AND FEW RIGHTS. THE CASE OF THE BALKAN ROUTE

The rise of new migratory routes in the world has represented a response to the unsuccessful strategies adopted by States in the field of people mobility. The Balkan route, in Eastern Europe, came out from the migration crisis in 2015 and continues until today. The main goal of this note is to provide a detailed literature regarding the policies adopted by the States to manage migration along Balkan countries. It is also the aim of this paper to show how policies have produced changes in the route, violating the fundamental human rights instead of reducing the number of people trying to cross the borders to reach Europe but rather creating categories of marginalized people in marginalized places

Jeep Nation: Wilderness Ideology and the American Icon

The subculture of the Jeep brand has enabled the lasting success of the Jeep Wrangler. A warrior of World War II, the Jeep was credited with helping to win the war, while also befriending the common American soldier. When the Jeep Wrangler was introduced thirty years after the conclusion of World War II, sales skyrocketed. Today the Jeep Wrangler is still the highest grossing Jeep vehicle. Boasting characteristics for the rugged outdoorsman, this thesis argues that the successful utilization of wilderness ideologies by the Jeep brand promotes the successful sales of the Jeep Wrangler. Through the methods of historical and visual analysis, this thesis offers reasoning behind consumption of the iconic Jeep Wrangler. Individuals have become so far removed from nature that one of the avenues in which to return is through consumption. The concepts of both wilderness and nature have become loaded with socially constructed meanings, many of which transform nature and wilderness into an un-natural notion. After a brief synopsis of the origin of the Jeep brand in World War II, the thesis will complete a thorough analysis of the physical Jeep Wrangler in correlation to various wilderness ideologies including name, color, and build. Subsequently the thesis will complete a thorough analysis of marketing campaigns of the Jeep Wrangler in correlation to various wilderness ideologies in order to showcase how culturally embedded media can sway consumption

Salivary VIP concentrations are elevated in humans after acute stress

The purpose of this research was to evaluate two salivary neuropeptides in the context of the stress response. The research was focused first and foremost on evaluating the usefulness of salivary Neuropeptide Y (NPY) and salivary vasoactive intestinal peptide (VIP) as stress indicators. Secondly, we questioned whether these markers help us in distinguishing between physical and psychological stress. Psychological stress can be experienced in a situation such as that in anticipation of an important exam or mental task. Physical stress can be experienced usually by strenuous exercise. Salivary NPY and salivary VIP are two neuropeptides that are released as a result of sympathetic and parasympathetic activity respectively. These two biomarkers are measured extensively in the blood or plasma but they are not routinely measured in saliva (Morgan et al., 2000). These neuropeptides will be evaluated in conjunction with the following salivary indicators cortisol, dehydroepiandrosterone (DHEA) (Morgan et al., 2004) and amylase (Nater et al., 2006) of the stress response. Depending on the stressful situation or stress paradigm, we used an indicator or biomarker profile in conjunction with the use of psychological assessments in order to measure the intensity of the stress response. In other situations, the biomarker profile with the aid of psychological and physical assessment tools helped us differentiate between psychological stress and physical stress. In essence, we used a matrix approach using a combination of physiological and psychological measures to develop a stress profile that could be used to determine both the degree and the nature of the stress response experienced by subjects. In this study we evaluated NPY and VIP as salivary biomarkers using different stress paradigms. We also studied the effects of the following possible confounders on the stress response: circadian variation, water, and coffee intake. Therefore, to accomplish this salivary samples were taken and s-cortisol, s- DHEA, s-amylase, s-NPY and s-VIP were measured. Assessments (Thayer Activation-Deactivation Checklist, State-Trait Anxiety Inventory, and Borg Rating of Perceived Exertion Scale) were also administered in order to evaluate the psychological state of the subjects with respect to anxiety and their perception of physical exertion. The main findings of the study indicate that a brief intense exercise lasting minutes elicited a stress response with significant increases in s-cortisol, s-DHEA, s-amylase and s-VIP. A less rigorous exercise did not elicit a stress response with no significant increases in s-cortisol, s-DHEA ,s-amylase and s-VIP. A longer intense exercise lasting hours elicited a stress response with significant increases only in s-cortisol. In addition, s-VIP displays a circadian variation which peaks with cortisol at 0800h

SDN Architecture and Southbound APIs for IPv6 Segment Routing Enabled Wide Area Networks

The SRv6 architecture (Segment Routing based on IPv6 data plane) is a promising solution to support services like Traffic Engineering, Service Function Chaining and Virtual Private Networks in IPv6 backbones and datacenters. The SRv6 architecture has interesting scalability properties as it reduces the amount of state information that needs to be configured in the nodes to support the network services. In this paper, we describe the advantages of complementing the SRv6 technology with an SDN based approach in backbone networks. We discuss the architecture of a SRv6 enabled network based on Linux nodes. In addition, we present the design and implementation of the Southbound API between the SDN controller and the SRv6 device. We have defined a data-model and four different implementations of the API, respectively based on gRPC, REST, NETCONF and remote Command Line Interface (CLI). Since it is important to support both the development and testing aspects we have realized an Intent based emulation system to build realistic and reproducible experiments. This collection of tools automate most of the configuration aspects relieving the experimenter from a significant effort. Finally, we have realized an evaluation of some performance aspects of our architecture and of the different variants of the Southbound APIs and we have analyzed the effects of the configuration updates in the SRv6 enabled nodes

Supramolecular assembly and mechanical properties of dermis

The present work is a part of a wider research project which aims at the in vitro tissues and biohybrid generation. The process of generating biological tissues requires benchmarks in order to define the optimal set of design and performance parameters for the tissue of interest. As a consequence of that, my efforts have been devoted to the study of natural tissue. In particular I have focused my attention to their composition, microstructure and macroscopic properties. The first part of the thesis reviews recent studies concerning the assembly and spatial arrangement of some biological macromolecules of interest, which compose the extracellular matrix. The extracellular matrix is indeed largely responsible for the macroscopic physical properties of connective tissues. Skin has been chosen as model of connective tissue to study. This choice is motivated by the fact that skin is a more general model rather then tendons, which are mainly subjected to uniaxal tension, and the osmosis-supported cartilage. An experimental campaign has been designed in order to gather information on dermal composition and structure, and how these characteristics can affect the macroscopic behaviour of the tissue. The results of this experimental campaign are shown in the second part of the work. At last two constitutive equations are presented. Both of them are developed within the framework of continuum mechanics. The first one is a full three dimensional model able to capture the elastic behaviour of dermis at large deformations. The second model is able to predict the viscoelastic behaviour. Both model accounts for the anisotropy of the native tissue and are structural model, since they contain parameters on the underlying histology. The development of these models provide noteworthy information on the performance of tissue-engineered constructs whose properties have been designed ab initio. In particular, since the mechanical properties of biohybrids can be on-line monitored during culturing in bioreactors. Thus constitutive models can provide cues on the evolution of the mechanical properties, giving the chance to investigate on the complex relationship between mechanical stimulus and tissue remodelling

Marshall system for aerospace system simulation (MARSYAS), user's manual

The capabilities of the Marshall system for aerospace system simulation (MARSYAS) and how to use it are described. MARSYAS is a software system that allows easy setup and control of the simulation of the dynamics of large physical systems on a digital computer. The physical systems are modeled in the form of block diagrams or equations. The blocks can have multiple inputs and multiple outputs, and they can be nested to form hierarchies. The block diagrams can contain transfer functions, nonlinear and logical functions, equations, analog computer elements and FORTRAN programs. The input format of the equations can be combinations of nonlinear, time-varying differential equations and algebraic equations in their original format. MARSYAS could also serve as a storage and retrieval system for models as a basis for a model configuration control system on a central time-shared computer. The outputs of the simulation system can be not only time-responses but also other analysis data such as frequency response, power spectrum and stability parameters. The MARSYAS translator is written in FORTRAN running on the Univac 1108 computer under the EXEC 8 operating system