Sistema SONAR per prospezioni subacquee con segnali non impulsivi

L'obiettivo del presente lavoro di tesi è stato sviluppare un sistema di tipo SONAR per il tracciamento del profilo del fondale marino e per il rilevamento di oggetti sommersi, impiegando, diversamente dalle metodologie tradizionali, segnali di test non impulsivi come il segnale MLS e Sine Sweep Lineare e Logaritmico. Sono stati testati i comportamenti di questi diversi segnali confrontandoli con le tecniche impulsive, effettuando prove sperimentali sia in aria, presso il laboratorio della Facoltà di Ingegneria dell’Università di Parma, che in acqua, in ambiente controllato ed in mare, utilizzando la vasca di prova presso La Spezia ed il motoscafo “Whitehead III” messi a disposizione per questo studio dalla WASS (Whitehead Alenia Sistemi Subacquei S.p.A.). Parallelamente è stato necessario sviluppare un software che consentisse di emettere e ricevere i segnali, di elaborarli e infine di visualizzare graficamente i risultati ottenuti. Gli esperimenti effettuati mostrano che le suddette tecniche, in particolare il segnale Sine Sweep, producono immagini del fondale con un guadagno nel rapporto segnale-rumore maggiore ed una migliore risoluzione spaziale rispetto a quelle ottenibili con le tecniche di tipo impulsivo. The aim of this thesis is to develop a sonar system for plotting the sea bottom and locating objects by means other than traditional methodologies: non-impulsive signals as MLS signal and Linear Sine Sweep and Logarithmic Sine Sweep. The behaviour of these signals have been tested and compared with traditional pulse-based sonar techniques by means of several experiments conducted both in air - by the laboratory of the Faculty of Engineering of the University of Parma - and underwater, using the test pond in La Spezia and a motor boat disposed for this work by WASS (Whitehead Alenia Sistemi Subacquei S.p.A). A new software implementation has been developed to emit and receive the signals, as well as to elaborate them and visualize the results. The experiments conducted show that the proposed techniques produce images of the bottom profile with higher signal-to-noise ratio and better spatial resolution than those obtainable with the impulsive technique. Moreover, signal-to-noise ratio increases using Sine Sweep signal instead of MLS one

Identificazione dei sistemi locali, analisi del territorio e traiettorie di sviluppo sostenibile: ipotesi per la Val di Cecina

Obiettivo è riflettere concretamente su un tema, quello dello sviluppo locale, che oggi attrae un crescente interesse sia in termini di analisi teorica che di politiche pubbliche. Necessaria premessa è, a tal fine, il tema dell'identificazione dei sistemi locali, che verrà trattato in riferimento all'Italia prima e alla Toscana poi. In seguito si prende in esame il caso della Val di Cecina, area dalle incerte traiettorie di sviluppo, per la quale si imposta uno schema di analisi territoriale integrata

Defining and measuring polycentric regions: the case of Tuscany

Polycentric development in regions has many dimensions, which involve several definitions and measures. This paper tackles the problem of defining and measuring polycentricity under an integrated and multi- dimensional perspective. Firstly, the policy relevance of polycentricity is analysed. Then, the paper identifies the definitions and measures of polycentricity by surveying the literature. It also provides a taxonomy among two main aspects involved in the definition of polycentricity: the morphological dimension and the functional dimension. Based on this background, an empirical analysis is carried out, by using data about population and commuting flows in the Tuscany Region (Italy). The results show that Tuscany can be viewed as a polycentric spatial structure, both considering rank-size distribution of cities and spatial interaction.Polycentric development; spatial structure; rank-size estimations; spatial interaction; Tuscany

The Recent Decline in Italian Social Services System, Amid Financial Crises and Socio-Political Constraints

In Italy the social services have always been a marginal part of social protection system and only since the late twentieth century had a development. This development, however, at some time has stopped. The process of “liability reduction” of the national government towards the local welfare system and recent cuts in social funding, in fact, have led to a new decline of social services. This essay presents a longitudinal view of the issues that concerned the social services sector over the course of the last two decades. The objective of the analyses is to demonstrate that the recent decline in the social services system is tied to the economic recession of 2008, but was above all caused by the reaffirmation of the traditionally marginal position of social services on the agenda of the national government. The theoretical framework used considers the development of social services of the years of the late twentieth century as a passage of the extension and consolidation process of the Italian system of social protection built since the '60s. However, in this process the social services was placed at the edge of the main path and this determined the weakness of their position. Thus, the external event represented by the international financial crisis has had a negative impact almost exclusively on social services, while the historical features and the path of structuring of the Italian system of social protection has prevented the same happen for the other sectors (pensions, health)

Cutaneous permeation and penetration of sunscreens: formulation strategies and in vitro methods

Sunscreens are the most common products used for skin protection against the harmful effects of ultraviolet radiation. However, as frequent application is recommended, the use of large amount of sunscreens could reflect in possible systemic absorption and since these preparations are often applied on large skin areas, even low penetration rates can cause a significant amount of sunscreen to enter the body. An ideal sunscreen should have a high substantivity and should neither penetrate the viable epidermis, the dermis and the systemic circulation, nor in hair follicle. The research of methods to assess the degree of penetration of solar filters into the skin is nowadays even more important than in the past, due to the widespread use of nanomaterials and the new discoveries in cosmetic formulation technology. In the present paper, different in vitro studies, published in the last five years, have been reviewed, in order to focus the attention on the different methodological approaches employed to effectively assess the skin permeation and retention of sunscreens

Defining and measuring polycentric regions: the case of Tuscany

Polycentric development in regions has many dimensions, which involve several definitions and measures. This paper tackles the problem of defining and measuring polycentricity under an integrated and multi- dimensional perspective. Firstly, the policy relevance of polycentricity is analysed. Then, the paper identifies the definitions and measures of polycentricity by surveying the literature. It also provides a taxonomy among two main aspects involved in the definition of polycentricity: the morphological dimension and the functional dimension. Based on this background, an empirical analysis is carried out, by using data about population and commuting flows in the Tuscany Region (Italy). The results show that Tuscany can be viewed as a polycentric spatial structure, both considering rank-size distribution of cities and spatial interaction

La "sostenibilità" socio-economica di una risorsa non rinnovabile: il marmo e Carrara

L'estrazione sostenibile di una risorsa naturale non rinnovabile sembra davvero un ossimoro. Eppure, se si considera la natura sfaccettata del significato di sostenibilità, estrarre la risorsa in modo sostenibile può venir inteso come un processo volto a promuovere un benessere duraturo per la popolazione locale. Pertanto, la ragion d’essere dell'estrazione del marmo - un'attività con impatti così elevati sulla salute degli abitanti e sull'ambiente - è di alimentare attività economiche con forti e diffuse ricadute su un territorio che oggi è attraversato da forti criticità economiche e sociali. Il volume, che si è avvalso dei preziosi punti di vista di stakeholder coinvolti durante la ricerca, fa il punto sia sulla situazione socio-economica di Carrara sia sulla filiera locale del marmo, proponendo infine linee guida, anche innovative, per le politiche di regolamentazione dell'attività estrattiv

In vitro evaluation of some parameters involved in mucoadhesion of aqueous polymeric dispersions

Context: The mucoadhesive formulations are constantly developing due to their relevance in the drug delivery to various districts of the organism. Objective: The purpose of this study was to find a direct link between physicochemical properties of the polymers and their adhesive ability in order to offer guidelines for the development of mucoadhesive semisolid formulations. Materials and methods: Twelve polymers were dispersed in water and characterized with regard to their mucoadhesiveness, apparent viscosity, contact angle on solid surface, and hydrodynamic diameter of their molecules. The adhesive properties were related to the other measured parameters. Results and discussion: The data seem to indicate the existence of an optimal value of viscosity, around 5–6 Pa s, to obtain the highest mucoadhesiveness of the polymeric dispersions. Regarding the molecular sizes, the best mucoadhesive performances seem to be given from polymers with a hydrodynamic diameter lower than 350–400 nm. In any case, the ability to wet the surface by the polymeric dispersion seems to play an essential role in bioadhesion process, capable of strongly limiting the phenomenon. Conclusions: Performing simple in vitro measurements, it seems possible to identify the best polymeric concentration to obtain a semisolid formulation with good mucoadhesive properties

Questioning polycentric development and its effects: issues of definition and measurement for the Italian NUTS 2 Regions

Polycentric development is a widely-used term both in academic research and in the normative agenda. However, its theoretical foundations and economic implications are still unknown and the concept of polycentricity still does not have a shared definition, or a shared measurement method. The aim of this paper is twofold. Firstly polycentricity is defined and measured at a NUTS 2 regional level, by comparing functional and morphological methods. Secondly, in the light of the role assigned to polycentric development in terms of policy, the paper investigates the relationships between the degree of regional polycentricity and the key economic variables of performance – namely competitiveness, social cohesion and environmental sustainability. The main finding was that functional and morphological methods led to similar results. In addition, a correlation was found between polycentricity and a more unequal income distribution and a higher level of productivity, especially when polycentricity was measured in functional terms. No stable correlations were found between polycentricity and measures of environmental sustainability, such as land consumption and greenhouse emissions