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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Self-Assembled Monolayers (SAMs) in Organic Field-Effect Transistors

Leonardi, Francesca <1986> 09 April 2014 (has links)
Organic printed electronics is attracting an ever-growing interest in the last decades because of its impressive breakthroughs concerning the chemical design of π-conjugated materials and their processing. This has an impact on novel applications, such as flexible-large-area displays, low- cost printable circuits, plastic solar cells and lab-on-a-chip devices. The organic field-effect transistor (OFET) relies on a thin film of organic semiconductor that bridges source and drain electrodes. Since its first discovery in the 80s, intensive research activities were deployed in order to control the chemico-physical properties of these electronic devices and consequently their charge. Self-assembled monolayers (SAMs) are a versatile tool for tuning the properties of metallic, semi-conducting, and insulating surfaces. Within this context, OFETs represent reliable instruments for measuring the electrical properties of the SAMs in a Metal/SAM/OS junction. Our experimental approach, named Charge Injection Organic-Gauge (CIOG), uses OTFT in a charge-injection controlled regime. The CIOG sensitivity has been extensively demonstrated on different homologous self-assembling molecules that differ in either chain length or in anchor/terminal group. One of the latest applications of organic electronics is the so-called “bio-electronics” that makes use of electronic devices to encompass interests of the medical science, such as biosensors, biotransducers etc… As a result, thee second part of this thesis deals with the realization of an electronic transducer based on an Organic Field-Effect Transistor operating in aqueous media. Here, the conventional bottom gate/bottom contact configuration is replaced by top gate architecture with the electrolyte that ensures electrical contact between the top gold electrode and the semiconductor layer. This configuration is named Electrolyte-Gated Field-Effect Transistor (EGOFET). The functionalization of the top electrode is the sensing core of the device allowing the detection of dopamine as well as of protein biomarkers with ultra-low sensitivity.
172

Design and fabrication of biocompatible scaffolds for the regeneration of tissues

Barbalinardo, Marianna <1981> 09 April 2014 (has links)
Regenerative medicine and tissue engineering attempt to repair or improve the biological functions of tissues that have been damaged or have ceased to perform their role through three main components: a biocompatible scaffold, cellular component and bioactive molecules. Nanotechnology provide a toolbox of innovative scaffold fabrication procedures in regenerative medicine. In fact, nanotechnology, using manufacturing techniques such as conventional and unconventional lithography, allows fabricating supports with different geometries and sizes as well as displaying physical chemical properties tunable over different length scales. Soft lithography techniques allow to functionalize the support by specific molecules that promote adhesion and control the growth of cells. Understanding cell response to scaffold, and viceversa, is a key issue; here we show our investigation of the essential features required for improving the cell-surface interaction over different scale lengths. The main goal of this thesis has been to devise a nanotechnology-based strategy for the fabrication of scaffolds for tissue regeneration. We made four types of scaffolds, which are able to accurately control cell adhesion and proliferation. For each scaffold, we chose properly designed materials, fabrication and characterization techniques.
173

Nano-fabrication of complex functional structures using non- conventional lithography

Hemmatian, Zahra <1980> 09 April 2014 (has links)
In Chapter 1 I will present a brief introduction on the state of art of nanotechnologies, nanofabrication techniques and unconventional lithography as a technique to fabricate the novel electronic device as resistive switch so-called memristor is shown. In Chapter 2 a detailed description of the main fabrication and characterization techniques employed in this work is reported. Chapter 3 parallel local oxidation lithography (pLOx) describes as a main technique to obtain accurate patterning process. All the effective parameters has been studied and the optimized condition observed to highly reproducible with excellent patterned nanostructures. The effect of negative bias, calls local reduction (LR) studied. Moreover, the use of AC bias shows faster patterning process respect to DC bias. In Chapter 4 (metal/ e-SiO2/ Si nanojunction) it is shown how the electrochemical oxide nanostructures by using pLOx can be used in the fabrication of novel devices call memristor. We demonstrate a new concept, based on conventional materials, where the lifetime problem is resolved by introducing a “regeneration” step, which restores the nano-memristor to its pristine condition by applying an appropriate voltage cycle. In Chapter 5 (Graphene/ e-SiO2/ Si), Graphene as a building block material is used as an electrode to selectively oxidize the silicon substrate by pLOx set up for the fabrication of novel resistive switch device. In Chapter 6 (surface architecture) I will show another application of pLOx in biotechnology is shown. So the surface functionalization combine with nano-patterning by pLOx used to design a new surface to accurately bind biomolecules with the possibility of studying those properties and more application in nano-bio device fabrication. So, in order to obtain biochips, electronic and optical/photonics devices Nano patterning of DNA used as scaffolds to fabricate small functional nano-components.
174

I Gesuiti americani espulsi in Italia e Joaquín Camaño (1767-1814) / The Americans Jesuits expelled in Italy and Joaquín Camaño (1767-1814) / Los jesuitas americanos en Italia y Joaquín Camaño (1767-1814)

Piciulo, Viviana Silvia <1963> 12 September 2014 (has links)
Joaquín Camaño fu un gesuita della Provincia del Paraguay, vissuto nell' esilio italiano la maggior parte della sua vita dal 1767 al 1820. Il suo lavoro e la sua fama possono essere considerati di minore importanza se paragonati a molti altri gesuiti esiliati per ordine di Carlo III alla fine del XVIII secolo in Emilia-Romagna. Attraverso la mia ricerca approfondisco il ruolo di J. Camaño quale personaggio minore che entra nella vita degli altri espulsi tramite un dinamico network relazionale di cui è stato uno dei principali artefici. Il mio obiettivo è stato quello di studiare l'impatto che ebbero gli esuli gesuiti americani, attraverso la vita di Joaquin Camaño, sul mondo intellettuale italiano, europeo ed americano dopo l'espulsione del 1767. Egli, con i suoi studi, si inserisce nella rinnovata e vivace retorica del “Mondo Nuovo” che in quegli anni assume un grande dinamismo. Nato nella modesta città di La Rioja, in Argentina, si erge come un brillante cartografo, etnografo e linguista nel contesto dell'Illustrazione europea grazie alla sua particolare vita da missionario. Dopo l'espulsione, Joaquin Camaño, insieme ad altri numerosi confratelli americani, arriverà a Faenza, nello Stato Pontificio, dedicandosi allo studio della cartografia, dell'etnografia e delle lingue americane. Le sue ricerche si collocano in un momento nevralgico per la storia del pensiero linguistico-antropologico, quando l'osservazione diretta e la riflessione teorica dei fenomeni si misuravano con la grande varietà umana ormai riscontrata nel mondo. / Joaquín Camaño was a Jesuit Province of Paraguay, who lived in 'exile Italian most of his life from 1767 to 1820. His work and his reputation may be considered minor when compared to many other Jesuits exiled by order of Charles III in the late eighteenth century in Emilia-Romagna. Through my research I deepen the role of J. Camaño which minor character who enters the lives of others expelled by a dynamic relational network of which he was one of the principal architects. My goal was to study the impact that the exiles were American Jesuits, through the life of Joaquin Camaño, the Italian intellectual world, Europe and America after the expulsion of 1767. He, with his studies, is part of the renewed and vibrant rhetoric of the " New World" in those years is of great dynamism. Born in the small town of La Rioja, Argentina, stands as a brilliant cartographer, ethnographer and linguist in the context of the European Enlightenment thanks to its life as a missionary. After the expulsion, Joaquín Camaño, along with many other fellow Americans, will arrive in Faenza, in the Papal States, devoting himself to the study of cartography, ethnography and American languages. His research interests lie at a nerve center for the history of linguistic thought -anthropological, when direct observation and theoretical reflection phenomena were measured with the wide variety now found in the human world. / Joaquín Camaño fue un jesuita de la Provincia del Paraguay que vivió en el exilio italiano la mayor parte de su vida. Su obra y su fama la podemos considerar menor si lo comparamos a tantos otros jesuitas que realizaron obras importantísimas dentro del concierto de los grandes personajes de fines del siglo XVIII activos en el destierro decretado por Carlos III como Lorenzo Hervas y Panduro. En mi investigación profundizo el rol de Camaño como personaje secundario que entra en las vidas de los otros expulsos a través de una dinamica red de trabajo en la que colaboró activamente y de la que era uno de los principales artífices.
175

L'amministrazione Johnson e le origini della distensione. 1964-1968 / The Johnson Administration and the origins of Détente. 1964-1968

Bacchitta, Sandra <1982> 26 May 2014 (has links)
La tesi analizza una parte della politica estera dell’amministrazione Johnson, e più specificamente l’avvio del dialogo con l’Urss in materia di non proliferazione e controllo degli armamenti e la revisione della China policy, inquadrando entrambe nell’adattamento della cold war strategy all’evoluzione sistema internazionale, argomentando che la distensione intesa come rilassamento delle tensioni e ricerca di terreno comune per il dialogo, fosse perlomeno uno degli strumenti politici che l’amministrazione scelse di usare. Il primo capitolo analizza i cambiamenti che interessarono il Blocco sovietico e il movimento comunista internazionale tra la fine degli anni Cinquanta e l’inizio degli anni Sessanta, soprattutto la rottura dell’alleanza sino-sovietica, e l’impatto che essi ebbero sul sistema bipolare su cui si basava la Guerra Fredda. Il capitolo secondo affronta più specificamente l’evoluzione delle relazioni tra Stati Uniti e Unione Sovietica, il perseguimento di una politica di distensione, dopo la crisi dei missili cubani, e in che relazione si trovasse ciò con lo status della leadership sovietica a seguito dei cambiamenti che avevano avuto luogo. Soffermandosi sulla questione del controllo degli armamenti e sul percorso che portò alla firma del Trattato di Non-proliferazione, si analizza come la nuova rotta intrapresa col dialogo sulle questioni strategiche sia stato anche un cambiamento di rotta in generale nella concezione della Guerra Fredda e l’introduzione della distensione come strumento politico. Il terzo capitolo affronta la questione della modifica della politica verso Pechino e il processo tortuoso e contorto attraverso cui l’amministrazione Johnson giunse a distaccarsi dalla China policy seguita sino ad allora. / The research intends to investigate two aspects of Johnson’s foreign policy: the establishment of a dialogue and the pursuit of cooperation with Soviet Union, regarding arms control measures and non-proliferation; the reassessment of the American policy towards Communist China and the slow detachment from the previous approach. The Sixties saw the international system becoming more complex and fragmented, the strategic balance getting closer to a condition of equality but also becoming less manageable due to nuclear proliferation; the rivalry between the two blocs was changing as well, due to the Sino-Soviet split, the increasing of contacts between eastern and western Europe and the willingness to avoid tensions between the superpowers. Being wary of both the dangers and the interdependence inherent in the bilateral relationship led to the decision to seek a common ground on strategic issues and to the establishment of a dialogue. Also during those years, the administration begun to explore the convenience of a different approach toward Communist China, which was clearly bound to emerge as a power in its own, and the possibilities that a new policy would have opened up. Both issues illustrates how the Johnson Administration, in order to face the challenges of its time, considered new options and took measures, breaking with the past, and adopting the relaxation of tensions and dialogue, or at least the possibility of it, as a policy. The research, which focuses on the debate and the decision-making process within the Administration, assumes that by doing so the administration introduced the policy of détente as at least one of the options available to the United States. Therefore the analysis of Johnson’s policies towards the main communist powers, and their challenges, may help to achieve a better definition and understanding of Détente, in its origins and motivations.
176

Understanding the Combined Role of Internal and External Factors in New Service Development Process within the Professional Knowledge Intensive Business Service Firms

Petraityte, Lina <1978> 06 June 2014 (has links)
Our research asked the following main questions: how the characteristics of professionals service firms allow them to successfully innovate in exploiting through exploring by combining internal and external factors of innovation and how these ambidextrous organisations perceive these factors; and how do successful innovators in professional service firms use corporate entrepreneurship models in their new service development processes? With a goal to shed light on innovation in professional knowledge intensive business service firms’ (PKIBS), we concluded a qualitative analysis of ten globally acting law firms, providing business legal services. We analyse the internal and factors of innovation that are critical for PKIBS’ innovation. We suggest how these firms become ambidextrous in changing environment. Our findings show that this kind of firms has particular type of ambidexterity due to their specific characteristics. As PKIBS are very dependant on its human capital, governance structure, and the high expectations of their clients, their ambidexterity is structural, but also contextual at the same time. In addition, we suggest 3 types of corporate entrepreneurship models that international PKIBS use to enhance innovation in turbulent environments. We looked at how law firms going through turbulent environments were using corporate entrepreneurship activities as a part of their strategies to be more innovative. Using visual mapping methodology, we developed three types of innovation patterns in the law firms. We suggest that corporate entrepreneurship models depend on successful application of mainly three elements: who participates in corporate entrepreneurship initiatives; what are the formal processes that enhances these initiatives; and what are the policies applied to this type of behaviour.
177

The Università, compagnia, ed accademia del disegno

Barzman, Karen-edis. January 1900 (has links)
Thesis (Ph. D.)--Johns Hopkins University. / Includes bibliographical references.
178

Democrazia e cattolicesimo negli Stati Uniti. La libertà di religione e il pensiero di John Courtney Murray / Democracy and Catholicism in the United States. Religious freedom and the works of John Courtney Murray

Cadeddu, Francesca <1985> January 1900 (has links)
L'elaborato affronta il pensiero di John Courtney Murray dal punto di vista teologico e politico, sottolineandone le influenze esterne ai circoli intellettuali cattolici e la particolare rilevanza per l'integrazione della comunità cattolica nella società statunitense. / This work analyses the thought of John Courtney Murray from the political and theological perspective. It focuses on the influences received by the jesuit from non-Catholic intellectual circles and the relevance for the integration of the Catholic community in the American society.
179

Giunti semirigidi con barre incollate per strutture lignee = Ductile moment-resistant steel-timber connections with glued-in bars

Andreolli, Mauro January 2011 (has links)
Il lavoro di tesi riguarda la caratterizzazione meccanica di un giunto, adatto per la realizzazione di differenti configurazioni in strutture intelaiate pesanti di legno, costituito da un elemento metallico flangiato collegato agli elementi strutturali in legno per mezzo di barre incollate. Questo sistema di connessione presenta alcune interessanti proprietÃ&nbsp; meccaniche in termini di prestazioni meccaniche, versatilitÃ&nbsp; e prefabbricazione. Un modello analitico in grado di valutare la risposta del giunto in termini dei parametri meccanici chiave (modalitÃ&nbsp; di rottura, resistenza ultima, rigidezza e capacitÃ&nbsp; rotazionale) à ̈ stato proposto e validato attraverso unâ€TMampia campagna sperimentale. A tale scopo il metodo per componenti, originariamente proposto per giunti semi-rigidi in acciaio, à ̈ stato adattato per modellare i giunti acciaiolegno, consentendo l'applicazione del capacity design e permettendo di progettare connessioni in grado di presentare valori di duttilitÃ&nbsp; necessari ad applicazioni in campo sismico. Le prove effettuate hanno mostrato una soddisfacente rispondenza tra i risultati teorici e quelli sperimentali: in particolare la previsione affidabile delle modalitÃ&nbsp; di rottura del giunto, permette la progettazione di connessioni resistenti a momento in grado di presentare alte deformazioni plastiche senza fenomeni di rotture fragili, con un notevole grado di duttilitÃ&nbsp; strutturale a livello globale e di dissipazione energetica in seguito a sisma. ENGLISH VERSION This thesis investigates the mechanical characterisation of a joint, suitable for different configurations within a heavy timber frame, consisting of a wooden element connected to a steel stub by means of an end-plate and glued-in steel rods. This connection system has some interesting properties in terms of mechanical performance, versatility and prefabrication. An analytical model to predict the joint response in terms of its key parameters (e.g. failure mode, ultimate resistance, stiffness and rotation capacity) is proposed and validated through an extensive experimental programme. The component method, originally proposed for semi-rigid joints in steel frameworks, is adapted in order to set up a feasible general model for steel–timber joints, enabling application of the capacity design approach and offering the required ductility for applications in seismic zones. The tests carried out indicate satisfactory agreement between theoretical and experimental results: the reliable prediction of joint failure modes allows design of moment-resistant connections that can sustain high plastic deformation without brittle rupture, with a remarkable degree of global ductility and energy dissipation under alternate loading.
180

Management of Bridge infrastructural Networks in seismic Areas

Zanini, Mariano Angelo January 2015 (has links)
This study deepens key issues related to the seismic emergency management and deterioration state assessment of roadway and railway infrastructural networks by proposing a series of procedures and methodologies through the use of scientific-based analyses in the field of optimal management of infrastructural assets. This thesis is subdivided in several chapters, in which, the issues of quantification of the bridge structures’ deterioration state are intertwined with those related to the estimation of the seismic vulnerability assessment, from punctual level (single bridge) to territorial scale (infrastructural network). The key topics discussed in this work are, at punctual level, statistical analyses on the effectiveness of in-situ investigations for the bridges’ seismic fragility estimation, sensitivity analyses on the influence of geometrical parameters on the seismic vulnerability assessment and the construction of fragility curves for bridges subjected to deterioration of key structural components. At territorial scale, analyses of the restoring costs for bridge stocks, construction of life-cycle curves for bridges subjected to deterioration, simulations of time-dependent earthquake scenarios for infrastructural networks and procedures for the management of seismic emergency for railway networks are presented.

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