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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.
131

An improved backcalculation method to predict flexible pavement layers moduli and bonding condition between wearing course and base course

Al Hakim, Bachar January 1997 (has links)
The aim of this research project is to develop an improved backcalculation procedure, for the determination of flexible pavement properties from the Falling Weight Deflectometer (FWD) test results. The conventional backcalculation methods estimate the pavement layer moduli assuming full adhesion exists between layers in the analysis process. The method developed in this research can predict the interface condition between the wearing and the base courses in addition to the layer moduli, which can be considered an improvement to the existing procedures. A two stage database procedure has been used to predict the above parameters and to facilitate the determination of the deflection insensitive parameters. The need for this improvement arises from the large number of debonding failures which have been reported in the literature between the wearing and base courses, and the theoretical studies which identified the significance of including the interface bonding condition in the analysis process. The validation of the improved method has been carried out firstly by comparing the backcalculated results for ninety theoretical pavements with their hypothetical values, and secondly by comparing the improved procedure results with other well known programs such as WESDEF and MODULUS. Full scale pavement testing using the FWD has been performed and the backcalculated results compared with measured values for the pavement materials. Indirect tensile tests for resilient modulus of bituminous materials were carried out on cores extracted for the pavements, whereas Dynamic Cone Penetrometer (DCP) tests were conducted for the unbound materials. The Backcalculated and the physically measured results correlated well, validating the improved procedure.
132

Multi-Protocol Label Switching Traffic Engineering with QoS / Multi-Protocol Label Switching Trafikteknik med QoS

Mian, Azhar Ali, Khalid, Sardar Usman January 2010 (has links)
The world has emerged as a global village. Internet has brought an amazing change in the era of modern communications. Demand for multimedia applications and an ever increasing amount of VoIP traffic have increased data rate and bandwidth requirements. It has become a big chal-lenge to provide best quality applications. Traffic engineers are working hard over Internet Protocol (IP) and Routing Protocols (RPs) in order to cope with this challenge. IP networks have offered these services efficiently until now, but there are several issues with IP routing that affect the Quality of Service (QoS). Multi-Protocol Label Switching (MPLS) has emerged as an agile technology which promises effective security together with high speed data delivery. MPLS networks use switching instead of conventional routing. MPLS doesn’t replace existing IP networks, but guarantees instead better QoS in existing IP networks as well as future routing technologies, providing thus a suitable environment for Traffic Engineering (TE). The Class of Service (CoS) architecture provided by MPLS can easily be coordinated with IP QoS mecha-nisms. Traffic can be switched based on resource utilization and network performance instead of using static routing techniques such as selecting a path with least cost, optimizing thus the MPLS network for heavy application at desired quality. / Världen har blivit en global by. Internet har inneburit en fantastisk förändring i en tid präglad av modern kommunikation. Efterfrågan på multimediaapplikationer och en allt större mängd VoIP-trafik har ökat datahastighet och krav på bandbredd. Det har blivit en stor utmaning att ge bästa kvalitet ansökningar. Trafiken tekniker arbetar hårt over Internet Protocol (IP) och routingprotokoll (RPS) för att klara av denna utmaning. IP-nät har erbjudit dessa tjänster på ett effektivt fram tills nu, men det finns flera problem med IP-routing som påverkar Quality of Service (QoS). Multi-Protocol Label Switching (MPLS) har utvecklats till en flexibel teknik som utlovar effektiv säkerhet tillsammans med hög hastighet leverans. MPLS-nätverk används byte istället för konventionella routing. MPLS ersätter inte de befintliga IP-nät, utan garantier i stället bättre QoS i befintliga IP-nät samt framtida routing-teknik, vilket har en lämplig miljö för trafikteknik (TE). Den klass som (COS) arkitektur som MPLS kan enkelt styras med IP QoS meka-nismer. Trafiken kan kopplas grundas på resursutnyttjande och nätverksprestanda istället för att använda statisk routing tekniker som att välja en väg med lägsta kostnad, vilket optimerar därmed MPLS nät för tunga ansökan till önskad kvalitet.
133

Die Kleurlinge van Eersterust se siening van hul huidige en toekomsteige posisie in die breë Suid-Afrikaanse bevolkingstruktuuur

Smit, Henry B. January 1971 (has links)
Please read the abstract in the dissertation. / Dissertation (MA)--University of Pretoria, 1971. / gm2014 / Sociology / Unrestricted
134

A Traffic Engineering Approach to Differentiated Multicast Services over MPLS Networks

Barabas, Toni January 2012 (has links)
Currently, a viable solution to provide multicast provision over a multiprotocol label switch with traffic engineering (MPLS-TE) domain is unavailable because of the missing link able to couple multicast traffic distribution with an MPLS-TE enabled network. This is due to the limited or less research investigation that was done in this area. Most of the investigation methods tackle the problem individually such as deploying internet protocol (IP) multicast in a plain network or MPLS domain but without considering a combination of both technologies that is aware of differentiated services requirements. This thesis presents an alternative solution for the multicast differentiated services provision problem over a MPLS-TE enabled network. The approach is exposed and analyzed through a practical solution that was developed within a network simulation environment. The research presented in this thesis orchestrates the already available technologies offered by the multicast protocols suite and differentiated services (DiffServ) aware MPLS-TE that allows applying separately the constraint-based routing and admission control to different classes of services. The novelty and solution of this thesis relies on using MPLS constraint-based routing concepts (e.g.traffic trunks) in order to solve TE issues revealed during multicast traffic distribution.
135

Modelling traffic incidents to support dynamic bus fleet management for sustainable transport

Polyviou, Polyvios January 2011 (has links)
The continuous implementation of highly technological functions and specifically intelligent transport systems in public transport highlights the need of highly efficient, accurate and reliable bus operations network. Intelligent transport systems can support a variety of functions, including dynamic bus fleet management which has yet to be established in most bus fleets in the UK in a systematic way. In order to support dynamic bus fleet management by detecting the fundamental role of bus and traffic incidents in bus-based public transport, a microscopic simulation model capable of modelling the impact of the individual incidents‟ characteristics on bus operations has been developed and applied to a variety of scenarios. This research draws on a review of existing literature on bus fleet management and available computer software in this field. It investigates research gaps in modelling the impact of traffic incidents on overall bus performance; it describes the design and development of the new simulation model, SIBUFEM (Simulating Incidents for Bus Fleet Management) for modelling bus operations during whole day periods in which incidents of different types can occur. The model simulates a high frequency bus service using existing field data and incorporates the continuous circulation of buses along the bus route. It uses journey time profiles, passenger-dependent bus stop dwell times and deterministic time-dependent queuing theory to model traffic incidents and the impact of their characteristics on the bus performance parameters. The model results, presented in this thesis, focus on performance measures including but not limited to bus journey times, passenger waiting times and bus delays resulting from various bus and traffic incidents. Incidents vary from bus breakdowns, to traffic incidents such as road-works, traffic accidents, burst water mains, disabled vehicles and illegal parking; in SIBUFEM they are specified in terms of their location, duration and severity (i.e. loss of capacity). The model has been applied to a main bus corridor in Southampton, UK, with a base case of „normal‟ operations established, for comparison with results from 24 different incident scenarios, and using key model performance parameters of average bus journey time, bus speed and excess waiting time. This PhD demonstrates the functionality of SIBUFEM with model results demonstrating the extent to which passenger waiting times increase with increasing incident severity and duration. The overall comparison of the simulation results showed that the more severe the level of severity or the longer the duration of an incident, the higher the expected impact of the event on the overall bus performance was. In terms of the incident location parameter, the effect is greater when the incident occurs in the middle of the bus route than when it occurs at the end. The effect of incident location is especially evident in the case of traffic incidents such as roadworks, traffic accidents and illegal parking. Findings from this research also demonstrated that these incidents are usually more severely affected by a change in an incident parameter than by bus breakdown incidents. The thesis concludes with a discussion on potential dynamic bus fleet management strategies and how SIBUFEM can be further developed to allow these strategies to be evaluated. SIBUFEM is capable of modelling traffic incidents to support dynamic bus fleet management and, thus, encourage the use of intelligent transport systems applications in bus operations. This offers great potential in the field of bus-based public transport as part of a guidance tool for bus operators, as well as the way to increase bus level service thereby increasing customer satisfaction and thus the development of a sustainable transport system.
136

Caracterización modal de guías arbitrarias y aplicación a dispositivos de microondas

Cogollos Borras, Santiago 05 June 2009 (has links)
En esta tesis se desarrollan una serie de técnicas de análisis y diseño de dispositivos de microondas que harán hincapié en la necesidad de precisión y eficiencia en los mencionados procesos tanto para analizar como para diseñar dispositivos de microondas que se describirán de manera exhaustiva en la tesis. A su vez, se desarrollan técnicas de aceleración de algoritmos de análisis que reducen en gran medida el tiempo de caracterización de estructuras que componen los dispositivos. Debido a la complejidad de los dispositivos actuales, un incremento en la velocidad de análisis mejora a su vez los tiempos requeridos para el diseño y desarrollo de estos complejos dispositivos. Esto es debido a que las técnicas CAD requieren algoritmos de optimización que invocan a los módulos de análisis repetidas veces. Este objetivo de aumento de velocidad y precisión en el análisis y diseño ha requerido una cuidadosa elección de técnicas así como una profunda mejora de las mismas. / Cogollos Borras, S. (2002). Caracterización modal de guías arbitrarias y aplicación a dispositivos de microondas [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/5081 / Palancia
137

Decentralization in Wei Te-sheng's Film

Wang, Ji 04 April 2018 (has links)
As one of the most prominent Taiwanese film director, Wei Te-sheng’s films have been the focus of attention from publicity and film prize committees. Most of his film works focus on Japan-Taiwan theme. Based on auteur theory, this thesis examines the colonial and postcolonial relationship between Japanese and Taiwanese by analyzing the Taiwanese film director Wei Te-sheng’s three films, Cape No.7 (2008), Seediq Bale (2011), and Kano (2014). From the historical view in terms of the colonial relationship between Taiwan and Japan, this thesis reveals the Taiwanese’s ambivalence toward its ex-colonizer and explores the reasons behind the particular and complex relationship between Taiwanese and Japanese colonists. Since decentralization is the most noticeable manifestation of such colonial and postcolonial relationship, this thesis also probes into the reason why decentralization evokes nostalgic feelings among Taiwanese. This thesis interprets Wei’s film based on auteur theory. Auteur’s imprint is to be found both in style and basic motifs in Wei’s films as following three distinguished features: non-linear narrative, voiceover, and the use of allusion. There contain two aspects of the colonial relationship reflected on Wei Te-sheng’s films, the oppressor and the oppressed, and the emotional bond. Explanations of paradoxical pro-Japan attitude are manifested in the following two aspects: ineffectiveness of the KMT government, and contribution of Japanese colonial government, including improvement of infrastructure, promotion of economics growth, and colonial education. Three major films directed by Wei have all set in the rural areas. The praise for the energy and enthusiasm of rural dwellers is indicative of the shift in focus from urban to rural areas. Cape No.7 and Kano, reveal that Taiwanese hold a deep emotional appeal for building warm and harmonious communities in a society constantly shaped by industrialization and urbanization. Cape No.7 and Kano have brought a familial sense of community back to the audience. On the island’s mad rush toward modernization, these two films presented what was lost and sacrificed during this process: harmony with nature, a sense of community, time-honored cultural traditions and local cultures and ways of life. The popularity of the two films reflects the audience’s romantic imagination toward the irretrievable rural life, and reveals that they were nostalgic for the close-knit, intimate, direct interpersonal relationships in rural areas. The atomization of existence is associated with the current situation of cities, where each individual human beings is increasingly isolated. Under such circumstances, two films featuring a sense of community evoked a historical retrospection of the urbanization. The seemingly conservative rural areas preserve the precious complex that people aspire to retain, though it might be spotlighted through a reminiscing filter, the close-knit community with intimate, direct and simple interpersonal relationships.
138

Den professionella förskolläraren - En textanalys av den svenska förskolans läroplan och den nya zeeländska förskolans läroplan

Svensson, Sandra January 2016 (has links)
Syftet med denna studie är att med hjälp av en kvalitativ innehållsanalys analysera den svenska läroplanens och den nya zeeländska läroplanens innehåll för att synliggöra hur förskolläraryrkets professionalism framträder samt diskutera vilka möjligheter och hinder läroplanerna skapar i relation till förskolläraryrkets professionaliseringsprocess. Dessa länders läroplaner valdes då initiativet till läroplanerna tillkommit på olika sätt samt att innehållet och utformningen av innehållet skiljer sig åt. Den svenska läroplanen har tillkommit på initiativ av staten och den nya zeeländska har tillkommit internt på initiativ av verksamma förskollärare. Först analyserades respektive lands läroplan utifrån hur den professionella förskolläraren konstrueras utifrån studiens fyra kriterier för professionalism som grundar sig i den funktionalistiska professionsteorin. Sedan jämfördes likheter och skillnader utifrån vilka möjligheter och hinder läroplanerna skapar i relation till förskolläraryrkets professionaliseringsprocess. Båda läroplanerna beskriver att den professionella förskolläraren ska med sin förvärvade kompetens dokumentera och analysera för att kunna tillämpa lämpliga metoder utifrån alla barns intresse och behov samt utifrån föräldrars inflytande. Den svenska läroplanens mål är kort beskrivna utan förslag på metoder och den nya zeeländska läroplanens mål är utförligt beskrivna men utan förslag på metoder. Det är professionaliserande att förskollärarna i den svenska läroplanen har förtydligade arbetsuppgifter och ansvar medan det är deprofessionaliserande att förskollärarna inte är utskrivna i den nya zeeländska läroplanen. Båda läroplanerna innehåller omsorg och lärande men de beskrivs på olika sätt och läroplanerna kan ses som dokument som beskriver förskollärarnas yrkesetiska regler.
139

An MPLS-based Quality of Service Architecture for Heterogeneous Networks

Raghavan, Srihari 26 November 2001 (has links)
This thesis proposes a multi-protocol label switching (MPLS)-based architecture to provide quality of service (QoS) for both internet service provider (ISP) networks and backbone Internet Protocol (IP) networks that are heterogeneous in nature. Heterogeneous networks are present due to the use of different link-layer mechanisms in the current Internet. Copper-based links, fiber-based links, and wireless links are some examples of different physical media that lead to different link-layer mechanisms. The proposed architecture uses generalized MPLS and other MPLS features to combat heterogeneity. The proposed architecture leverages the QoS capabilities of asynchronous transfer mode (ATM) and the scalability advantages of the IP differentiated services (DiffServ) architecture. This architecture is constructed in such a way that MPLS interacts with DiffServ in the backbone networks while performing ATM-like QoS enforcement in the periphery of the networks. The architecture supports traffic engineering through MPLS explicit paths. MPLS network management, bandwidth broker capabilities, and customizability is handled through domain specific MPLS management entities that use the Common Open Policy Service (COPS) protocol to interact with other MPLS entities like MPLS label switch routers and label edge routers. The thesis provides a description of MPLS and QoS, followed by a discussion of the motivation for a new architecture. The MPLS-based architecture is then discussed and compared against similar architectures. To integrate the ATM and DiffServ QoS attributes into this architecture, MPLS signaling protocols are used. There are two common MPLS signaling protocols. They are Resource Reservation Protocol with traffic engineering extensions (RSVP-TE) and Constraint-Routed Label Distribution Protocol (CR-LDP). Both these protocols offer comparative MPLS features for constraint routed label switch path construction, maintenance, and termination. RSVP-TE uses UDP and IP, while CR-LDP uses TCP. This architecture proposes a multi-level domain of operation where CR-LDP operates in internet service provider (ISP) networks and RSVP- TE operates in backbone networks along with DiffServ. Qualitative analysis for this choice of domain of operation of the signaling protocols is then presented. Quantitative analysis through simulation demonstrates the advantages of combining DiffServ and MPLS in the backbone. The simulation setup compares the network performance in handling mixed ill-behaved and well-behaved traffic in the same link, with different levels of DiffServ and MPLS integration in the network. The simulation results demonstrate the advantages of integrating the QoS features of DiffServ, ATM functionality, and MPLS into a single architecture. / Master of Science
140

Funcionalização do 3,4,6-tri-O-acetil-D-glucal com sais de organotrifluoroboratos de potássio e reações de click chemistry para a geração e funcionalização de triazóis / Functionalization of 3,4,6-tri-O-acetyl-D-glucal with potassium organotrifluoroborate salts and click chemistry reactions for the generation and functionalization of triazoles.

Silva, Nathalia Cristina da Silva e 22 February 2013 (has links)
No presente trabalho, foi desenvolvida uma metodologia sintética para a funcionalização de um monossacarídeo derivado da D-glicose através do Rearranjo de Ferrier, utilizando-se um sal de organotrifluoroborato de potássio como nucleófilo. Em seguida, foi feita a reação de cicloadição azida-acetileno com cobre, através de estratégias simples e eficientes, que seguem a filosofia da click chemistry, permitindo a preparação de uma série de compostos com grande diversidade estrutural, possuindo dois anéis heterocíclicos e diversos substituintes, com promissora atividade biológica. Dando continuidade ao projeto, foi feita a metanólise dos grupamentos acetila, com carbonato de potássio e metanol. Assim, as novas moléculas adquirem maior hidrofilicidade e podem ser enviadas para novos testes biológicos, para fins de comparação com as anteriores. A partir dos compostos desprotegidos, foi feita a mesilação seletiva da hidroxila primária do açúcar e a substituição com selenolato de sódio, com a obtenção de seleno-carboidratos inéditos. Em uma segunda etapa do trabalho, exploramos a reatividade do núcleo triazólico, com a reação de troca Te/Li seguida de captura por eletrófilo. O material de partida foi sintetizado a partir do fenil acetileno. Com o triazol telurado em mãos, partimos para as reações de troca e captura por eletrófilo. Utilizamos diferentes tipos de eletrófilos, como aldeídos, cetonas, iodetos, dentre outros. / We developed a synthetic methodology for the functionalization of a monosaccharide derived from D-glucose, using the Ferrier rearrangement with a potassium organotrifluoroborate salt as the nucleophile. This way, a series of coumpounds with high structural diversity and two heterocyclic rings having different substituents were produced, using the azide-acetylene cycloaddition reaction. Through this simple and efficient methodology, that follows the \"click chemistry\" philosophy, we could synthesize molecules with promising biological activity. Continuing the project, we performed the methanolysis of the acetyl groups, with potassium carbonate and methanol. Thus, the new molecules become more hydrophilic and could be sent to new biological tests, for a comparison with the previous ones. From the deprotected compounds, we were able to mesilate the primary hydroxyl and substitute it with sodium selenolate, obtaining novel selenium-carbohydrates. In a second part of our work, we were able to exploit the triazole reactivity trough the Te/Li exchange reaction followed by the electrophile capture. The starting material was obtained from phenyl acetylene. With the teluratte in our hands, we set out to the exchange reactions, using several types of electrophiles, such as aldehydes, ketones, iodide, among others.

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