Academic literature on the topic 'ING-IND/01'

(iloh,tlcurr("!,1111111 ll111p .o; uflhe SlIllll1lt" r mUn!\4 lOn prt>cipil:lliull anomalies a nti St"a SU l f.IC(" Tt"mpt"1 a1lln"' (SST) a nUllul!it'.'i are pTt'St'IlI("d . n lir1 ) -)l' /u (1950..1479) rime St' 1; ("S uf 11l0n...nnn ind("x b co rn' l a h~d ....; Ih Iht"SST tillll' Sl'riCS al t"nch 1° ;<2° latitLIl1co! u nl:iluJt" box uf th t" \\(1(111 (>I,:eans usi ng COADS (Comprehensive O..:eanAllno...pl1("fl." Dala S('1)dn ta ttl "3riOUS timc IJgs o f lUonth s (i.t' .. l1luI11 h,'S of year s p recedi ng 'lI1.1 conc urrcnI lu Ihe1ll011Stllll1-)l'at) , Ctl lTclal ion..mups :'I ll' pn.-pUTl,.f 111111 Illaly"I'" 1(1 i.lclltify Il' IN."Oll lle ct it ln "-' Ilf llln ll....oon pTt'I,:ipil<ttiunwilh glubal S ~Ts.It is I'olin.! th ai tlll' lag,orrelatiuns .... ilh SST (Will 1:('01(31 and t'ilstt"m t'lluHt orial Padlic (Ninu-rl'l!inniliresuggl·..liw of IWlI I>p t' S o f inlt"raetjuns .....ith Ihe munsoun. The first on e, .... h il.:h sho ws pmili\'c <:orre lnlio n of summermonsoon pf('\.-ipililtion anoll1alit"s ",i lh Ihe ct"nlral and l":Jsl ..-mequaturial P<lciftc SST nnoUlal ies aboul a yea r be forelilt" 1l10 nsollfl. sUggl°.!>1Sthat lhe monsoon which follo ws abmlt a )'t'lir la ll'r ur tX'currence ofwaml t"pisode of EI..Nin~Suut hem Oscillatiun (ENSO) is generally ....-eltc It is also suggestetJ Ihal this inleract io n might be taki ng placelhruugh Ihe in llue nce or nOr1h em hemisp here int er tempera tures. Th e seco nd I)-PC of inleraclion of equ alorialPaci fic SST ....i lh mon soon is revealed through the strung n~al ive co rrela tio ns bqinning befo re lh e summer monsoon an d continuing ....; lh g~ a l er magnitud e an d o~ r ....i der extent. suuest ing th ai a .....arm SST anomaly j ust precedineanll concurrent to monsoon ~aso n weaken s th e monsson.AiNt"li intcf<n'lions bctween Ihe Indian Ocean and monsoon are also emph a si ~d in the anal ysis. Two key~ginns are ide nt ified. Th e cen tra l Indian Ocun south o f th e equalor shoW!strong positive corre la tions during (helalt' no n hl'm ",inler a nd spring. Th e other key Tq!'ion is in the north Ind ian Geran. Th e correlations are significanllynt'ga li\'e. Some teleconnections with th e Atlantic basin are also revealed which are ralhe rdifficuh to explain but ma yfind usefu l ap plications in monitoring and long-range forecas line of the monsoon.

nel XIX secolo si riscontra la nascita della nave per passeggeri. l'analisi delle trasformazioni architettoniche della struttura navale dalla nave mercantile a quella passeggeri, consente di valutare come si siano creati spazi adatti ai viaggiatori. tutto questo in concomitanza con l'evoluzione generale delle imbarcazioni ottocentesca, dall'uso di nuovi materiali alle moderne tecnologie (macchina a vapore). i cambiamenti navali per far spazio ai passeggeri non riguardano solo la struttura ma anche le architetture degli ambienti interni. infatti, nascono locali dedicati solamente ai viaggiatori di prima classe che, nel corso dei decenni, diventano sempre più lussuosi e confortevoli, tanto da poter essere paragonabili, per stile architettonico e arredo, agli interni di normali edifici del secolo.

Il lavoro che in questa sede si viene a presentare ha la finalità di raggruppare l'artiglieria ottomana custodita in vari musei europei, realizzando un catalogo dei pezzi, con analisi e confronti anche con modelli veneziani. La cornice temporale si colloca nel periodo fra XV e XVIII secolo, mentre la cornice geografica entro cui verrà collocato il lavoro è moto vasta: da San Pietroburgo ad Istanbul, da Venezia a Londra. Il lavoro si presenta con una prima parte di inquadramento storico e istituzionale, una parte centrale relativa agli scambi fra ottomani ed europei, ai metalli, alle fonderie, agli arsenali e alle imbarcazioni e ad una terza ed ultima parte relativa propriamente alle artiglierie e al loro studio. L'obiettivo è quindi quello di indagare quest'ambito ancora poco conosciuto dando inizio ad un approccio scientifico e metodologico sullo studio delle artiglierie ottomane.

This thesis is focused on the calculation of ship motions and on the evaluation of added resistance in waves. A partial desingularized panel method based on potential theory has been developed. Rankine sources are distributed on the hull and at small distance above the free surface. In such way only the free surface is desingularized. This choice allows to consider also thin hull shapes at the bow where desingularization could cause numerical problems. The main advantage of this approach leads to reduce the computational time, especially when non linear effects are considered, provided an adequate source-panel center vertical distance is selected. The fluid domain boundaries have been represented as a structured grid consisting of flat quadrilater panels. In the linear case the boundary conditions have been applied on the mean body wetted surface and the free-surface is considered at the calm water level. By using an Eulerian timestepping integration scheme the kinematic and dynamic boundary conditions are updated on the free-surface at every time-step. After the potential is obtained, the pressure on the mean hull surface can be calculated and forces and moments can be determined by integrating the pressure on the body surface. Therefore in two-dimensional environment an introduction of non-linear effects has been analysed. In particular a 2D body exact method has been developed. The added resistance is determined by a near field method integrating the second-order pressure on the body surface. Then it is corrected using a semi-empirical method to allow to consider the wave reflection of short waves. The adequacy of the results has been verified applying the code to different test cases and comparing the numerical output with experimental data available in literature. Furthermore in order to discuss the improvements obtained with this present method the results have been compared with another numerical method in frequency domain.

The following doctoral thesis addresses all the stability failures embraced by the Second-Generation Intact Stability criteria (SGISc). These criteria are under finalization within the sub-Committee at the International Maritime Organization (IMO). SGISc are one of the most discussed topic since the session in 2008 and they drew the attentions not only of the international scientific community but also of other stakeholders such as designers and shipyards. It is forecast that the second-generation criteria will be finalized and published in an official document at IMO by 2020 session. The new regulation has introduced a modern method to apply the criteria that is called multi-layered approach: it consist of three different vulnerability level with increasing accuracy and complexity. One of the aims of this dissertation is to evaluate, both qualitatively and quantitatively, how the SGISc will affect existing vessels and new projects. To chase this main object, it has been necessary to develop a set of computational codes, for each stability failure and vulnerability level, integrated with an existing in-house software already developed. Before beginning to compile the codes, the phenomena physics behind each stability failure has been studied together with a detailed analysis of the regulations texts. Subsequently, a comprehensive campaign of application on a representative mega yacht unit and on a Ro-Ro pax ferry has been carried out in order to verify and validate the computational codes developed. Navy vessel and container-ship have been included in the analysis because they are deemed to be vulnerable to the phenomena addressed by SGISc. To identify a relationship between the stability failures and main design parameters, a set of parent hull variations has been carried out. To better understand which parameters are more relevant in each specific phenomenon, it has relied on a useful tool adopted in systems engineering: the Design Structure Matrix (DSM). Thanks to DSM it has been possible to classify the direction and the magnitude of relationships among parameters introduced by the SGISc.

2004/2005
Parametrically excited roll motion has become a relevant technical issue, especially in recent years, due the increasing number of accidents related to this phenomenon. For this reason, its study has attracted the interest of researchers, regulatory bodies and classification societies. The objective of this thesis is the developing of nonlinear analytical models able to provide simplified tools for the analysis of parametrically excited roll motion in longitudinal regular and irregular long crested waves. The sought models will take into account the nonlinearities of restoring and of damping, in order to try filling the gap with the analytical modelling in beam sea. In addition, semi-empirical methodologies will be provided to try extending the usual static approach to ship stability based on the analysis of GZ curve, in a probabilistic framework where the propensity of the ship to exhibit restoring variations in waves is rationally accounted for. The thesis addresses three main topics: the modelling of parametric roll in regular sea (Chapter 2 to Chapter 5), the modelling of parametric roll motion in irregular long crested sea (Chapter 6 and Chapter 7) and the extension of deterministic stability criteria based on the analysis of geometrical GZ curve properties to a probabilistic framework (Chapter 8). Chapter 1 gives an introduction, whereas Chapter 9 reports a series of final remarks. For the regular sea case an analytical model is developed and analysed both in time domain and in frequency domain. In this latter case an approximate analytical solution for the nonlinear response curve in the first parametric resonance region is provided by using the approximate method of averaging. Prediction are compared with experimental results for four ships, and the analytical model is investigated with particular attention to the presence of multiple stable steady states and the inception of chaotic motions. The influence of harmonic components higher than the first one in the fluctuation of the restoring is also investigated. In the case of irregular sea, the Grim's effective wave concept is used to develop an analytical model for the long crested longitudinal sea condition, that allows for an approximate analytical determination of the stochastic stability threshold in the first parametric resonance region. Experimental results are compared with Monte Carlo simulations on a single ship, showing the necessity of a tuning factor reducing the hydrostatically predicted magnitude of parametric excitation. The non-Gaussianity of parametrically excited roll motion is also discussed. Finally, on the basis of the analytical modelling of the restoring term in irregular waves, an extension of the classical deterministic approach to ship static stability in calm water is proposed, to take into account, although is a semi-empirical form, restoring variations in waves. Classical calm water GZ curve is then extended from a deterministic quantity to a stochastic process. By limiting the discussion to the instantaneous ensemble properties of this process, it is shown how it is possible to extend any static stability criterion based on the geometrical properties of the GZ curve, in a rational probabilistic framework taking into account the actual operational area of the ship and the propensity of the ship to show restoring variations in waves. General measures of restoring variations are also discussed, such as the coefficient of variation of metacentric height, restoring lever and area under GZ. Both the short-term and long-term point of view are considered, and the method is applied to three different ships in different geographical areas.

Terahertz gap corresponding to the frequency band of 0.3-3.0 THz is historically the last unexplored region of the electromagnetic spectrum left to be fully investigated. The major difficulty that has hampered the maturation of technologies operating in this region lies in the fact that much unlike its bordering millimeter and infrared regions, generation and detection of THz radiation is not trivial. Yet, such is the intriguing nature and properties of the terahertz radiations that the interest in this region has not faded. Infact, potential applications of THz based systems have emerged in various fields including biomedical imaging, safety and security, quality control and communication. Over the past decade, a lot of research work has been published with an aim to bridge this gap by both electronics and photonics based systems. While these attempts have succeeded to a certain extent, the available solutions either lack in terms of performance or are mostly bulky and difficult to integrate for portable and commercial purpose. This PhD dissertation focuses on the design and investigation of direct terahertz detectors which could be operated at room temperature and fabricated in standard silicon technologies, thereby making use of several advantages like high level of integration, low cost and small device size that these technologies have to offer. In particular, the emphasis is on developing and characterizing terahertz systems for imaging application by using field effect transistor devices as detectors. This objective is pursued in three parts. The first part (chapter 3) of the dissertation deals with the measurement and characterization challenges of terahertz systems. Unlike guided mode solutions, measurements of terahertz detectors and their systems require free space which presents several challenges due to atmospheric attenuation, spurious reflections and diffractions, beam shaping, and so on. Moreover, background noise is also significant considering that the detected signal is typically in the order of a few microvolts. In this regard, an overview of the most common techniques is given and a measurement methodology involving the use of a reference pyroelectric detector to measure the impinging input power and techniques for the evaluation of the detector under-test effective area is presented. The second part (chapter 4) is related to the investigation of variants of antenna-coupled field effect transistor and schottky barrier diode in standard 180 nm CMOS process as examples of direct detectors. During laboratory characterization, detection of terahertz radiation from schottky diode could not be achieved due to matching issues. Moreover, optimization of schottky diode by modifying its standard cell proved to be challenging as compared to field effect transistor, which can be optimized easily to enhance performance parameters and was therefore finally chosen as the preferred choice. The final part of the thesis (chapters 5 and 6) concerns with the implementation of analog readout interface to perform signal processing of detected terahertz signal. First, a single pixel consisting of on-chip antenna-coupled detector and a switched capacitor based filtering operation is designed and fabricated in 0.15μm process. The pixel is tested by performing both electrical and terahertz characterization, achieving high voltage responsivity value of 470 kV/W and a minimum NEP of 480 pW/sqrt (Hz). The interface architecture is highly repeatable and it can be used with any commercially terahertz source, even if its operation is limited by low modulation frequency. On the basis of the successful measurement results, an 8 x 6 terahertz array for real-time imaging application is fabricated in the same technology by modifying the interface architecture to make it power and area efficient.

A Wireless Sensor Network (WSN) is a distributed collection of resource constrained tiny nodes capable of operating with minimal user attendance. Due to their flexibility and low cost, WSNs have recently become widely applied in traffic regulation, fire alarm in buildings, wild fire monitoring, agriculture, health monitoring, building energy management, and ecological monitoring. However, deployment of the WSNs in difficult-to-access areas makes it difficult to replace the batteries - the main power supply of a sensor node. It means that the power limitation of the sensor nodes appreciably constraints their functionality and potential applications. The use of harvesting components such as solar cells alone and energy storage elements such as super capacitors and rechargeable batteries is insufficient for the long-term sensor node operation. With this thesis we are going to show that long-term operation could be achieved by adopting a combination of hardware and software techniques along with energy efficient WSN design. To demonstrate the hardware power management, an energy scavenging module was designed, implemented and tested. This module is able to handle both alternating current (AC) based and direct current (DC) based ambient sources. The harvested energy is stored in two energy buffers of different kind, and is delivered to the sensor node in accordance with an efficient energy supply switching algorithm. The software part of the thesis presents an analytical criterion to establish the value of the synchronization period minimizing the average power dissipated by a WSN node. Since the radio chip is usually the most power hungry component on a board, this approach can help one to decrease the amount of power consumption and prolong the lifetime of the entire WSN. The following part of the thesis demonstrates a methodology for power consumption evaluation of WSN. The methodology supports the Platform Based Design (PBD) paradigm, providing power analysis for various sensor platforms by defining separate abstraction layers for application, services, hardware and power supply modules. Finally, we present three applications where we use the designed hardware module and apply various power management strategies. In the first application we apply the WSN paradigm to the entertainment area, and in particular to the domain of Paintball. The second one refers to a wireless sensor platform for monitoring of dangerous gases and early fire detection. The platform operation is based on the pyrolysis product detection which makes it possible to prevent fire before inflammation. The third application is connected with medical research. This work describes the powering of wireless brain-machine interfaces.

The use of ICTs to stimulate socio-economic development has significantly grown in popularity in the recent years and has been boosted by the “mobile revolution†of the last decade. Despite the multi-year experience of academics, donor agencies and businesses, the failure rate of ICT for Development projects is still very high, resulting in a significant waste of resources. The multiple challenges that must be faced simultaneously in these projects make them more difficult than “traditional†ICT projects and recommendations such as best practices to face them have been suggested over the years. Nonetheless, the systematic replicability of these practices has never been addressed and project management and formalized development processes that address the particular challenges of the domain are extremely rare. This thesis presents a Maturity Model derived from the experience of researchers and practitioners, collected through an extensive literature review and interviews, that aims at providing a set of guidelines to be used throughout an ICT for Development intervention to increase the probability of success.