Dissertations / Theses on the topic 'Third generation'
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Fattahi, Hanieh. "Third-generation femtosecond technology." Diss., Ludwig-Maximilians-Universität München, 2015. http://nbn-resolving.de/urn:nbn:de:bvb:19-179044.
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Chirped pulse amplification in solid-state lasers is currently the method
of choice for producing high-energy ultrashort pulses, having surpassed
the performance of dye lasers over 20 years ago. The third generation of
femtosecond technology based on short-pulse-pumped optical parametric
chirped pulse amplification (OPCPA) holds promise for providing few-cycle
pulses with terawatt-scale peak powers and kilowatt-scale-average powers
simultaneously, heralding the next wave of attosecond and femtosecond science.
OPCPA laser systems pumped by near-1-ps pulses support broadband
and efficient amplification of few-cycle pulses due to their unrivaled gain
per unit length. This is rooted in the high threshold for dielectric breakdown
of the nonlinear crystals for even shorter pump pulse durations. Concomitantly,
short pump pulses simplify dispersion management and improve the
temporal contrast of the amplified signal.
This thesis covers the main experimental and theoretical steps required
to design and operate a high-power, high-energy, few-cycle OPCPA. This includes
the generation of a broadband, high-contrast, carrier envelope phase
(CEP)-stable seed, the practical use of a high-power thin-disk regenerative
amplifier, its efficient use for pumping a multi-stage OPCPA chain and compression
of the resulting pulses. A theoretical exploration of the concept
and its extension to different modes of operation, including widely-tunable,
high-power multi-cycle pulse trains, and ultrabroadband waveform synthesis
is presented.
Finally, a conceptual design of a field synthesizer with multi-terawatt,
multi-octave light transients is discussed, which holds promise for extending
the photon energy attainable via high harmonic generation to several kiloelectronvolts,
nourishing the hope for attosecond spectroscopy at hard-x-ray
wavelengths.
2
Hosseini-Khorasgani, Sayed-Ali. "Third harmonic generation in semiconductor superlattices." Thesis, University of Newcastle Upon Tyne, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318603.
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Griffiths, Gary. "Towards a third generation analyst workbench." Thesis, Teesside University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239173.
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Alam, Fakhrul. "Simulation of Third Generation CDMA Systems." Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/36387.
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The goal for the next generation of mobile communications system is to seamlessly integrate a wide variety of communication services such as high speed data, video and multimedia traffic as well as voice signals. The technology needed to tackle the challenges to make these services available is popularly known as the Third Generation (3G) Cellular Systems. One of the most promising approaches to 3G is to combine a Wideband Code Division Multiple Access (WCDMA) air interface with the fixed network of Global System for Mobile communications (GSM). In this thesis a signal simulator was implemented according to the physical layer specification of the IMT-2000 WCDMA system. The data is transmitted in a frame by frame basis through a time varying channel. The transmitted signal is corrupted by multiple access interference which is generated in a structured way rather than treating it as Additive White Gaussian Noise (AWGN). The signal is further corrupted by AWGN at the front end of the receiver. Simple rake diversity combining is employed at the receiver. We investigate the bit error rate at both uplink and downlink for different channel conditions. Performance improvement due to error correction coding scheme is shown. The simulator developed can be an invaluable tool for investigating the design and implementation of WCDMA systems.Master of Science
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Goble, Ryan A. "Narrative Accounts of Third-Generation Mexican-Americans: Bilingualism in a Third Space." CSUSB ScholarWorks, 2014. https://scholarworks.lib.csusb.edu/etd/40.
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While language shift is common in immigrant families by the third generation, maintenance of the heritage language is not impossible, depending on geography and other language socializing contexts such as parental communication and interactions with monolingual relatives of the minority language that provide the third generation with opportunities to use the language. The scholarship on the language shift to monolingual-English and the maintenance of Spanish in Latino immigrant families in the United States typically only considers how earlier generations socialize later generations to use one language over the other, without much attention to third-generation individuals themselves. Therefore, the purpose of the present thesis is to examine the narrative accounts of third-generation Mexican-American adults—the generation that typically loses the heritage language—in order to understand how they construct the experience of being socialized to use English and Spanish throughout their lives.
Data consist of ten, hour-long, transcribed audio-recorded interviews with ten third-generation Mexican-American individuals. The interview questions were quite open-ended about their use of Spanish. I conducted discourse analysis with the purpose of identifying narrative accounts that conveyed these third-generation individuals’ constructed realities regarding their own Spanish use and their interactions with various Spanish-speaking family members.
The findings indicate that the participants construct themselves as linguistically insecure with regard to their Spanish use. They explain their lack of ideologically “pure” Spanish in relation to socialization as they have interacted with various Spanish-speaking relatives throughout their lives. Moreover, they justify their lack of “pure” Spanish by constructing a third space for their Spanish use. They claim to use a new, localized variety of Spanish, which they consider to be illegitimate, thus self-defining as monolingual English speakers. However, I argue that their narrative accounts actually de-dichotomize bilingualism by opening the possibility of Third Space Spanish. Implications include the need for further research on the relationship between socialization, linguistic insecurity, and contested third space Spanish.
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Haussler, Nicholas I. "Third generation gangs revisited : the Iraq insurgency /." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Sep%5FHaussler.pdf.
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Thesis (M.A. in National Security Affairs)--Naval Postgraduate School, September 2005.Thesis Advisor(s): James Russell, Anne Marie Baylouny. Includes bibliographical references (p. 105-111). Also available online.
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Stergiou, Theodore. "Protocol security for third generation telecommunication systems." Thesis, University of Warwick, 2003. http://wrap.warwick.ac.uk/3023/.
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In this thesis, a novel protocol stack architecture is presented. The Future Core Networks System (FCNS) forms a secure reference model for use in packet-switched structures, with its applicability ranging from computer to telecommunication networks. An insight on currently used network protocol systems is given, analysing standardised sets of communication rules with respect to the security they afford to the messages exchanged. The lack of protection schemes for the internal protocol stack messages and the implementation pitfalls of their security architectures are described, in relation to the effects they have on the communication process. The OSI security model is also considered, with disadvantages identified in the placement of security functionality and its management. The drawbacks depicted for currently used systems form the motivation behind this work. The analysis of the FCNS follows, which is composed of three parts. In the first part, the FCNS communication layers are examined, with respect to the mechanisms used to establish, maintain and tear down a connection between peer entities. In the second part, the security mechanisms of the proposed reference architecture are given, including details on the FCNS keystream generator used for the security of the internal FCNS messages. Finally, the FCNS Error Protocol is depicted, illustrating the modes of operation and advantages it exhibits over currently used systems. The work then moves into presenting details of the software FCNS implementation, followed by the presentation of the results and measurements obtained by the case studies created. Comparisons are given in relation to the TCP/IP suite, to provide the means of identifying the FCNS applicability in various network environments. The work is concluded by presenting the FCNS functionality in delivering information for the UMTS, together with further work that may enhance the flexibility and use of the proposed architecture.
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Delivasilis, Dimitrios L. "Data security for third generation telecommunication systems." Thesis, University of Warwick, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404694.
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VILLANUEVA, UWE ROJAS. "COEXISTENCE BETWEEN THIRD AND FOURTH GENERATION TECHNOLOGIES." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2011. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=18484@1.
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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIORA chegada da tecnologia 4G acontece simultaneamente com a tecnologia que hoje temos (2G e 3G). Deste modo, uma pergunta natural é se elas vão conseguir coexistir ou se, no futuro, apresentarão problemas de coexistência. Para responder a estas perguntas, é preciso pesquisar para podermos predizer se, de alguma maneira, há possibilidade de falhas no futuro. E é assim que poderíamos explicar interferência, que é um problema que sempre existe e que se opõe à boa qualidade de serviço. No Brasil, já se discute o uso da frequência de 2.5 GHz, para serviços de 4a geração, por atender melhor as necessidades dos usuários. Isto que acontecerá também se, de alguma maneira, usarmos outras frequências como no caso de 900 MHz, que é considerada uma banda muito disputada na Europa. Existem operadoras que começaram a fazer testes com esta banda, e isso nos faz pensar que, de qualquer forma, teremos que conviver com a mesma banda em diferentes tecnologias. Assim, este trabalho apresenta um estudo de simulação de diversos casos de interferência e como cada um deles irá afetar o desempenho dos sistemas 4G coexistindo com sistemas mais antigos.
The arrival of 4G technology takes place simultaneously with the technology we have today (2G and 3G). Thus, a natural question is whether they will be able to coexist in the future or will present problems of coexistence. In order to answer these questions, it is necessary to search predicting if there is possibility of failure in the future. And that s how we explain interference, which is a problem that always exists and precludes good quality of service. In Brazil there is discussion about the use of 2.5 GHz frequency for 4G to better meet the users’needs. This will happened if in some way we use other frequencies as the case of 900 MHz band which is considered a hard fought in Europe. There are carriers that have begun to experiment with this band, and this makes us think that in any way we will live with different technologies in the same band. Thus, this work presents a simulation study of several cases of interference, in which each will affect the performance of 4G systems coexisting with older systems.
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Akbar, Ihsan Ali. "Markov Modeling of Third Generation Wireless Channels." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/32421.
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Wireless has proved to be one of the most important and fastest growing fields of communications especially during last few decades. To achieve reliable communication, we model a wireless system to analyze its performance and to find ways to improve the reliability of a particular system. Extensive research is being done to accurately model wireless systems, and to achieve better performance. Simulation techniques have been in use for many years to support the design and evaluation of electronic communication systems. Over the past few decades, Computer Aided Design (CAD) techniques (including both computerized analytical techniques and simulation) have matured, and are now usually applied at some point in the system design/development process.
The aim of this thesis is to find efficient algorithms that can model third generation wireless channels in a discrete sense. For modeling these channels, mathematical tools known as hidden Markov models are used. These models have proved themselves to be very efficient in many areas of electrical engineering including speech recognition, pattern recognition, artificial intelligence, wavelets and queuing theory. Wideband Code Division Multiple Access (W-CDMA) wireless communication parameters including channels fading statistics, Bit Error Rate (BER) performance and interval distribution of errors are modeled using different Markov models, and their results are tested and validated.
Four algorithms for modeling error sources are implemented, and their results are discussed. Both hidden Markov models and semi-hidden Markov models are used in this thesis, and their results are validated for the W-CDMA environment. The state duration distributions for these channels are also approximated using Phase-Type (PH) distribution.Master of Science
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Rowland, Cameron. "Third-generation German Perceptions of the Holocaust." Thesis, The University of Sydney, 2020. https://hdl.handle.net/2123/24672.
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This study explores the perspectives of nine third-generation Germans (educated across five federal states of Germany: Hamburg, Brandenburg, Berlin, Lower Saxony and North-Rhine Westphalia) surrounding their experience learning about the different victims of the Holocaust in their secondary schooling. As the research progressed, it became evident the majority of interviewees attributed their emotional connection to the victims of the Holocaust to their diverse secondary school experiences. It was apparent all interviewees felt a personal responsibility to remember the victims of the Holocaust. The state history curriculums grounded in them an understanding of their own individual responsibilities in ensuring such events of the Nazi period never happen again. Four interviewees wished to make connections between the 1930s and 1940s in Germany and contemporary right-wing political movements, expressing concern about calls by parties such as the Alternative for Deutschland (AFD) to reduce Holocaust memorialisation, including from within compulsory school curriculums. Germany’s culture of Holocaust memorialisation heightened four of my interviewee’s sensibilities about identifying with aspects of their German heritage.
Unlike the case for some second-generation Germans, most of my third-generation German interviewees were more likely to encounter the Holocaust transnationally because of increasing opportunities for travelling abroad and being on school exchange after the fall of the Berlin Wall. These transnational experiences of the Holocaust, sometimes consisting of being subject to negative stereotyping by non-Germans, has also, I believe, made some of my interviewees ambivalent about their own German identity.
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De, Bastiani Michele. "The Stability of Third Generation Solar Cells." Doctoral thesis, Università degli studi di Padova, 2016. http://hdl.handle.net/11577/3424345.
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In the lasts fifty years the tremendous evolution of modern technologies has gradually unbalanced the equilibrium between the production and the consumption of energy. Traditional energy resources, like coal, oil and natural gases, are no longer sufficient to satisfy the demand of energy without spoiling earth environment. Renewable energies have attracted a lot of attention because they are potential solution to this important problem. In particular photovoltaic solar cells are considered the most promising technology for a low-cost and environmentally friendly energy production. However, in order to exploit these technologies in real world applications, the complete physics of solar cells must be understood. Stability is one of the fundamental aspects and is related to the processes that regulate the energy conversion, both in long-term degradation as well in electrical stability. In this work the stability of two emerging categories of solar cells is thoroughly addressed: organic photovoltaics and organometal-halide perovskite.
In organic photovoltaics understanding the stability and degradation mechanisms of photoactive blends is required to achieve long device lifetimes. Recent reports on organic solar cells presenting power conversion efficiencies exceeding 10% have made the need to improve the device stability compelling. In general, instability is caused by the combination of light and atmospheric agents, with major roles of oxygen and water. The detrimental effects are electron trapping and photo-oxidation that break polymer conjugation and bleach the absorption. However, so far, no effective solution preserving low cost and flexibility has been achieved. The reason is that the degradation mechanisms are still unknown.
Solution-processable hybrid perovskite semiconductors have risen to the forefront of photovoltaics research, offering the potential to combine low-cost fabrication with high-power conversion efficiency (PCE). Originally used in dye-sensitized solar cell technology, the first architectures saw the use of TiO2, both in the form of mesoporous and compact films, as an electron extracting layer. Further development has been driven by empirical optimization strategies and testing of a variety of different architectures. These devices are divided in two categories: standard and inverted. Standard uses TiO2 (compact or mesoporous) to collect the electrons and a small molecule or polymer organic semiconductor for the holes, with record efficiencies of 21% and an open circuit voltage above 1 V; it must be noted that these devices exhibit a kind of electrical instability manifested as slow transient and hysteretic effects that severely affect the final efficiency. The inverted configuration is more similar to organic photovoltaics, exploiting similar materials for the extraction of photogenerated charges. These devices report lower efficiencies respect to standard device but a higher electrical stability which is manifest with stabilized efficiencies and apparently hysteresis-free behaviour.Negli ultimi cinquant’anni la rapida evoluzione delle tecnologie ha gradualmente sbilanciato l’equilibrio che esiste tra la produzione e il consumo dell’energia. Le risorse tradizionali che vengono sfruttate per la produzione di energia - carbone, petrolio e gas naturali - iniziano ad essere sempre meno sufficienti per soddisfare la richiesta di energia senza rischiare di danneggiare l’ambiente che ci circonda. E’ proprio per questo motivo che le energie rinnovabili attraggono sempre più interessi e attenzioni andandosi a candidare come una potenziale soluzione al fabbisogno energetico. Tra le energie rinnovabili, il fotovoltaico si conferma come una delle tecnologie più promettenti per fornire energia a costi contenuti nel rispetto dell’ambiente. Tuttavia per poter sfruttare appieno il potenziale di questa tecnologia la fisica e i meccanismi di conversione fotovoltaica devono essere studiati nel dettaglio. Tra questi la stabilità delle celle solari ricopre uno degli aspetti fondamentali, dove per stabilità si intendono sia la durata e il tempo di vita dei dispositivi sia la stabilità dei meccanismi elettrici delle celle. In questa tesi viene studiata nel dettaglio la stabilità di due tecnologie emergenti nel settore fotovoltaico: le celle solari polimeriche e le celle solari a base di perovskiti. Nelle celle solari polimeriche capire e comprendere i meccanismi di degrado dei materiali foto attivi permette di sviluppare nuovi materiali in grado di aumentare la durata e l’efficienza delle celle. In generale, il degrado di questi dispositivi è dovuto all’interazione tra la parte ultravioletta della luce e gli agenti atmosferici, in particolare ossigeno e vapore acqueo. Gli effetti del decadimento si riscontrano da un lato nella formazione di stati elettronici che fungono da “trappole” per le cariche fotogenerate diminuendo l’efficienza generale della cella, dall’altro nella modifica chimica dei materiali che porta ad una rottura delle catene polimeriche deteriorando completamente le proprietà ottiche della cella. Studiare e comprendere questi meccanismi è la corretta strada per lo sviluppo di nuovi materiali per celle più efficienti. L’introduzione delle perovskiti ibride ha rappresentato una rivoluzione nel settore fotovoltaico. Questa tipologia di materiali offre il vantaggio sia di essere processabile da soluzioni sia quello di avere un’efficienza confrontabile a quella del silicio cristallino. Inizialmente queste perovskiti erano utilizzate come materiale fotoassorbente in celle solari simili alle dye senistized solar cells (DSSCs). Questi primi dispositivi sfruttavano uno scaffold mesoporoso di diossido di titanio per estrarre gli elettroni. Successivamente, in seguito allo sviluppo empirico delle celle, lo scaffold mesoporoso è stato rimosso in favore di una configurazione planare. Tuttavia, in entrambe le configurazioni, queste celle hanno dimostrato una naturale instabilità elettrica che si manifesta in una forma di isteresi nella determinazione della caratteristica curva corrente/voltaggio. Questo fenomeno rende ambigua la determinazione finale dell’efficienza di questi dispositivi limitandone effettivamente le possibili applicazioni. In questa tesi viene presentata un’indagine completa delle cause e delle conseguenze di questo fenomeno, mostrando una possibile soluzione a questo problema.
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De, Scheemaecker Anne-Marie Esther. "Planning Strategies for Generational Succession in Flemish Third-Generation Family-Owned Businesses." ScholarWorks, 2017. https://scholarworks.waldenu.edu/dissertations/3762.
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Survival over generations is critical for family-owned businesses (FOBs). Only 3% of family firms survive the 3rd generation, and a succession strategy is the most challenging decision for family business leaders to make. The purpose of this multiple case study was to explore nonfinancial succession planning strategies that 3rd-generation FOB leaders in Flanders, Belgium, apply for the transition of ownership and leadership to the 4th generation. The conceptual framework for this study was the socioemotional wealth paradigm. Data were collected using semistructured interviews, archival document reviews, company internal and public documents, and press releases. Yin's 5-step data analysis was applied to identify themes and patterns. Analysis of the data revealed that, among these 3rd-generation FOBs, the socioemotional aspect of generational succession planning required strategies that simultaneously focused on successor suitability and well-being, consensus of the family, mode of transition, leadership and governance, and survival of the family firm. These findings may provide other, similar FOB leaders with insights into the dynamics of a successful transition of the 3rd-generation family firm to the next generation. Findings may be used to increase FOB survival rates, provide new job opportunities, contribute to community growth, and enhance the well-being of stakeholders. Successful family firms may engage in philanthropic activities as a way of transmitting legacies between generations.
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Jatunov, Loran Aleksandrovich. "Unified Performance Analysis for Third-Generation CDMA Systems." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5212.
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Analytic models for the performance of the forward link of 3G CDMA
systems using different maximum ratio combining (MRC) RAKE finger
weight assignments are presented. The spreading modulations under
investigation are the balanced QPSK and the complex-spreading QPSK.
The models are computationally efficient, accurate, and
applicable to Root Raised Cosine (RRC) pulse shaping with any
roll-off factor, variable processing gain, chip rate, and data
rate for orthogonal codes, random codes, quasi-orthogonal codes,
Gaussian noise, and realistic channel models. The expressions
derived are then used to obtain the so-called orthogonality
factor, which is commonly used in system-level simulations.
Next, closed-form mathematical expressions for the variance due to
infinite chips interfering in systems using arbitrary Nyquist
pulses are derived. These expressions are applicable to both the
forward link and the reverse link. For the latter, the existing
knowledge on the accurate and efficient estimation of the
performance of CDMA systems is extended by presenting closed
mathematical expressions for bandlimited systems using arbitrary
Nyquist pulses for both BPSK and Offset-QPSK (OQPSK)
modulation. The impact
of adjacent channel interference in bandlimited systems is
subsequently considered. Finally, mathematical expressions for the
accurate and efficient estimation of a CDMA system using RRC
pulse-shaping and a RAKE receiver in the presence of multipath
interference are presented.
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Lipton-Duffin, Josh. "First results from a third generation KRIPES system." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2002. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ63326.pdf.
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Alsolaim, Ahmad M. "Dynamically reconfigurable architecture for third generation mobile systems." Ohio : Ohio University, 2002. http://www.ohiolink.edu/etd/view.cgi?ohiou1178733781.
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Bullock, Ben Kasmin. "Third generation fermions as probes of new physics." Thesis, Durham University, 1994. http://etheses.dur.ac.uk/5487/.
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This thesis concerns the properties of two particles, the top quark and the tau lepton, the heaviest of the quarks and leptons, respectively, in the standard model of elementary particle physics. After a chapter introducing the standard model, the second concerns the tau lepton. Amongst all the quarks and leptons, the tau has the unique property that its polarisation can readily be measured at high energy colliders. We propose and develop new methods of using this unique property to search for new physics, such as Higgs bosons, and also for making an accurate measurement of the polarisation of taus produced via Z decay leading to a precision determination of the electroweak coupling. The third chapter of this thesis concerns the top quark. We perform the complete one- loop radiative corrections to the helicity amplitudes within the standard model. Even though the radiative corrections to top quark production and decay have already been calculated separately, our work makes it possible to combine the sequence of events by keeping full information on the correlations among final state particles.
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Yi, Jae Hwang 1963. "The third generation mobile telecommunication business in Korea." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/8918.
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Thesis (S.M.M.O.T.)--Massachusetts Institute of Technology, Sloan School of Management, Management of Technology Program, 2001.Includes bibliographical references (leaf 75).
The recent progress of the 3G technology and the up-coming 3G mobile telecommunication market environment of Korea were reviewed. On the basis of this knowledge, a simple system dynamics model was constructed. From the analysis of previous Korean mobile plethora, the model found that the network effect was the most important factor for the diffusion of mobile service in Korea. To investigate the competition on of 2G and 3G businesses, a more complicated model was designed. After its results, the initial large number of service contents of 3G will be helpful for expanding its market share for a short term, and the degree of technology performance and social demand is more helpful for a long term business. The model says the success of 30 businesses is quite dependent on how to quickly and effectively switch 2G subscribers into 3G subscribers. To do that just early entree to the market is not going to make a difference from 2G services. The 3G service providers have to decide whether it is right time to start the business by considering the technology performance differentiation from existing technology and the social need for bandwidth simultaneously.
by Jae Hwang Yi.
S.M.M.O.T.
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Tsoulos, George V. "Smart antennas for third generation wireless personal communications." Thesis, University of Bristol, 1996. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336243.
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Alam, Fakhrul. "Space Time Processing for Third Generation CDMA Systems." Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/29669.
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The capacity of a cellular system is limited by two different phenomena, namely multipath fading and multiple access interference (MAI). A Two Dimensional (2-D) receiver combats both of these by processing the signal both in the spatial and temporal domain. An ideal 2-D receiver would perform joint space-time processing, but at the price of high computational complexity. In this dissertation we investigate computationally simpler technique termed as a Beamformer-Rake. In a Beamformer-Rake, the output of a beamformer is fed into a succeeding temporal processor to take advantage of both the beamformer and Rake receiver. Wireless service providers throughout the world are working to introduce the third generation (3G) cellular service that will provide higher data rates and better spectral efficiency. Wideband CDMA (WCDMA) has been widely accepted as one of the air interfaces for 3G. A Beamformer-Rake receiver can be an effective solution to provide the receivers enhanced capabilities needed to achieve the required performance of a WCDMA system. This dissertation investigates different Beamformer-Rake receiver structures suitable for the WCDMA system and compares their performance under different operating conditions. This work develops Beamformer-Rake receivers for WCDMA uplink that employ Eigen-Beamforming techniques based on the Maximum Signal to Noise Ratio (MSNR) and Maximum Signal to Interference and Noise Ratio (MSINR) criteria. Both the structures employ Maximal Ratio Combining (MRC) to exploit temporal diversity.
MSNR based Eigen-Beamforming leads to a Simple Eigenvalue problem (SE). This work investigates several algorithms that can be employed to solve the SE and compare the algorithms in terms of their computational complexity and their performance. MSINR based Eigen-Beamforming results in a Generalized Eigenvalue problem (GE). The dissertation describes several techniques to form the GE and algorithms to solve it. We propose a new low-complexity algorithm, termed as the Adaptive Matrix Inversion (AMI), to solve the GE. We compare the performance of the AMI to other existing algorithms. Comparison between different techniques to form the GE is also compared. The MSINR based beamforming is demonstrated to be superior to the MSNR based beamforming in the presence of strong interference.
There are Pilot Symbol Assisted (PSA) beamforming techniques that exploit the Minimum Mean Squared Error (MMSE) criterion. We compare the MSINR based Beamformer-Rake with the same that utilizes Direct Matrix Inversion (DMI) to perform MMSE based beamforming in terms of Bit Error Rate (BER). In a wireless system where the number of co-channel interferers is larger than the number of elements of a practical antenna array, we can not perform explicit null-steering. As a result the advantage of beamforming is partially lost. In this scenario it is better to attain diversity gain at the cost of spatial aliasing. We demonstrate this with the aid of simulation.
Orthogonal Frequency Division Multiplexing (OFDM) is a multi-carrier technique that has recently received considerable attention for high speed wireless communication. OFDM has been accepted as the standard for Digital Audio Broadcast (DAB) and Digital Video Broadcast (DVB) in Europe. It has also been established as one of the modulation formats for the IEEE 802.11a wireless LAN standard. OFDM has emerged as one of the primary candidates for the Fourth Generation (4G) wireless communication systems and high speed ad hoc wireless networks. We propose a simple pilot symbol assisted frequency domain beamforming technique for OFDM receiver and demonstrate the concept of sub-band beamforming. Vector channel models measured with the MPRG Viper test-bed is also employed to investigate the performance of the beamforming scheme.Ph. D.
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Nader, Gustavo. "Ultra Wideband Interference on Third-Generation Wireless Networks." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/30046.
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As a license-exempt technology, Ultra Wideband (UWB) can be used for numerous commercial and military applications, including ranging, sensing, low-range networking and multimedia consumer products. In the networking and consumer fields, the technology is envisioned to reach the mass market, with a very high density of UWB devices per home and office. The technology is based on the concept of transmitting a signal with very low power spectral density (PSD), while occupying a very wide bandwidth. In principle, the low emissions mask protects incumbent systems operating in the same spectrum from being interfered with, while the wide bandwidth offers the possibility of high data rates, in excess of 250 Mbps.
UWB has been regulated to operate in the 3.1 to 10.6 GHz portion of the spectrum, with an emissions mask for the lower and upper bands outside this range. The commercial wireless mobile services based on third generation (3G) networks occupy a portion of the spectrum in the 2 GHz band, falling under the UWB emissions mask.
UWB and UMTS (Universal Mobile Telephone Systems) devices will coexist, sharing the same spectrum.
In this research, we investigate the UWB-3G coexistence problem, analyzing the impact of UWB on UMTS networks. Firstly, we review the mathematical model of the UWB signal, its temporal and spectral properties. We then analyze and model the effects of the UWB signal on a narrowband receiver. Next, we characterize the response of the UMTS receiver to UWB interference, determining its statistical behavior, and establishing a model to replicate it. We continue by proposing a link level model that offers a first order quantitative estimate of the impact of a UWB interferer on a UMTS victim receiver, demonstrating the potentially harmful effect of UWB on the UMTS link. We elaborate on that initial evidence by proposing and implementing a practical systemlevel algorithm to realistically simulate the behavior of the UMTS network in the presence of multiple sources of UWB interference.
We complete the research by performing UMTS system level simulations under various conditions of UWB interference, with the purpose of assessing its impact upon a typical UMTS network. We analyze the sensitivity of the main UWB parameters affecting UMTS performance, investigating the coverage and capacity performance aspects of the network. The proposed analysis methodology creates a framework to characterize the impact that mass-deployed UWB can have on the performance of a 3G system.
The literature on UWB-3G coexistence is inconclusive, and even contradictory, as to the impact UWB can have on the performance of third-generation wireless networks. While some studies show that UWB can be highly detrimental to 3G networks, others have concluded that both systems can gracefully coexist. Through this study, we found that at the current emissions limits regulated for UWB, a mass uptake of this technology can negatively affect the performance of third-generation (3G) wireless networks. The quality of service experienced by a 3G user in close proximity to an active UWB device can be noticeably degraded, in the form of reduced coverage range, poor voice quality (for a voice call), lower data rates (for a data session) or, in a extreme situation, complete service blockage. As the ratio of UWB devices surrounding a 3G user grows, the degradation becomes increasingly more evident. We determined that in order for UWB tocoexist with 3G networks without causing any performance degradation, a minimum power backoff of 20 dB should be applied to the current emission limits.Ph. D.
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Dowrick, Thomas Martin. "Biologically motivated circuits for third generation neural networks." Thesis, University of Liverpool, 2011. http://livrepository.liverpool.ac.uk/3024754/.
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Park, DongGook. "Cryptographic protocols for third generation mobile communication systems." Thesis, Queensland University of Technology, 2001.
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Fattahi, Hanieh Verfasser], and Ferenc [Akademischer Betreuer] [Krausz. "Third-generation femtosecond technology / Hanieh Fattahi. Betreuer: Ferenc Krausz." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2015. http://d-nb.info/1067400176/34.
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NUNES, WALDIR GALLUZZI. "PLANNING OF THIRD GENERATION MOBILE COMMUNICATION SYSTEMS (WCDMA-FDD)." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2002. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=2764@1.
Full textAbstract:
Os sistemas de comunicações móveis celulares de terceira
geração trazem a promessa de oferta de serviços diversos e
avançados de comunicação. Estes serviços implicam em
requisitos heterogêneos de desempenho da comunicação, e na
conseqüente influência de diferentes parcelas de carga
sobre a infra-estrutura empregada. Este trabalho contempla a
questão do planejamento, dado que pode haver cargas
heterogêneas simultâneas, e avalia fatores relacionados à
carga, propondo uma ferramenta para modelá-la
estatisticamente, de forma que se possa escolher raios de
célula apropriados como subsídio à atividade de
planejamento.Third generation mobile communication systems bring the promise of several and advanced communication services, which implies in heterogeneous performance requirements and consequent influence of diferent weighted loads over the communication infra-structure aplyed. This work treats the planning issue, given that there can be heterogeneous simultaneous loads, evaluating factors relateds to this loads and proposing a tool for its tatistical modeling, which allows to choose apropriated cell rays in aid of planning procedures.
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Inglesby, Alister Edward. "Biochemical and bioelectrochemical technology for third generation biofuel production." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648335.
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Gaskill, Dave. "Third-generation Advances in Thermal Printhead-based Chart Recorders." International Foundation for Telemetering, 1989. http://hdl.handle.net/10150/614662.
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International Telemetering Conference Proceedings / October 30-November 02, 1989 / Town & Country Hotel & Convention Center, San Diego, CaliforniaA brief recap of the effect thermal printhead technology has had on the common 8-channel strip chart recorder, followed by a summary of second and third generation products and their envolving capabilities. How these new instruments are being accepted and used by telemetrists and ground station managers who are faced with bigger tasks and shrinking budgets. A study of how today's telemetry professionals are shaping the 8-channel recorders of tomorrow, and the new capabilities they will bring.
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Zou, Elva Xin. "Sol-gel processed zinc oxide for third generation photovoltaics." Thesis, University of Oxford, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.559838.
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This thesis presents an experimental study of the incorporation and optimization of sol-gel processed aluminum doped zinc oxide (AZO) thin films in solar cell devices. I first optimized the optoelectronic properties of AZO thin films by manipulating the dopant incorporation, choice of precursor chemicals and post deposition anneal treatments. Results showed that improved performance could be attributed to several factors, including improved charge carrier concentration, mobility and conductivity. AZO thin films with transmittance of over 90% and resistivity values of the order of 10-2 Ω•cm have been achieved. I also demonstrated the successful application of these AZO thin films in organic photovoltaics (OPV), to serve as an alternative to ITO electrodes. I demonstrated greater than 2-fold improvement in device efficiency through the modification of the front contact/polymer interface using zinc oxide buffer layers. This improved the charge selectivity of the electrodes and energy level alignment at the interface while reducing the recombination of separated charges and the device's series resistance. Finally, I showed that the efficiency of inverted ZnO/PbS quantum dots solar cells can be enhanced by optimizing the p-type PbS thickness, UV treating the n-type ZnO layer and exposing the devices in the dark to nitrogen. Both ZnO and AZO systems were studied, and efficiency enhancement were demonstrated for a range of Al content from 0 to O.4at.%.
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Gibson, Victoria. "Third generation CPTED? : rethinking the basis for crime prevention strategies." Thesis, Northumbria University, 2016. http://nrl.northumbria.ac.uk/27318/.
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Crime Prevention Through Environmental Design (CPTED) is a concept which has developed over the past five decades through a range of fields. It is based on the premise that modifications to the built and natural environment can reduce both crime and fear, and improve the overall quality of life. CPTED relies on the cooperation of a variety of agencies; however, research has revealed important inherent difficulties regarding multi-agency working and that current practice is neither sustainable nor does it consider social characteristics which may impact upon crime and the effectiveness of CPTED initiatives. Criticisms of diverse factors relating to CPTED have been expressed but how robust such criticisms are and if suitable resolutions exist has not been explored. Using a mixed methods approach, this PhD seeks to improve and update the CPTED concept by addressing issues of communication and collaboration between CPTED stakeholders, and suggests robust ways of enhancing the social context within CPTED planning. The research answers the following fundamental questions: what are the underlying problems of the CPTED concept and how did they come to fruition; and can the approach to CPTED planning be re-examined and updated to reduce the inherent underlying difficulties and improve the transferability and practical application of CPTED initiatives. The research highlights language and definition inconsistencies in the CPTED framework, transferability and engagement issues between CPTED stakeholders and an unestablished but vital link between CPTED and social sustainability and context. The thesis delivers three major academic contributions to new knowledge. It firmly identifies failings in the CPTED concept since its inception to present; it proposes an updated framework which is theoretically driven, and represents a holistic catchment of all CPTED knowledge; and it makes a solid link between crime prevention and the sustainable development of communities highlighting its importance for context analysis.
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Falbo, Vincent. "English language & third generation programming language pedagogical practice analysis /." Online version of thesis, 2008. http://hdl.handle.net/1850/7879.
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Schramm, Jonathan. "Analysis of Third Person Cameras in Current Generation Action Games." Thesis, Högskolan på Gotland, Institutionen för speldesign, teknik och lärande, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hgo:diva-1903.
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The purpose of this project was to research the virtual camera systems used in current generation third person action games and to see what could be improved upon. To do this, different camera shots were categorized into camera archetypes, which also include post process and lens effects used. Information about the games was acquired by either looking through the game’s settings or by observing gameplay. Finally the results were compared to each other as well as the film industry and several improvements regarding usage of different features and camera shots were suggested.
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Sakata, M., S. Aoyagi, T. Ogura, and E. Nishibori. "Advanced Structural Analyses by Third Generation Synchrotron Radiation Powder Diffraction." American Institite of Physics, 2007. http://hdl.handle.net/2237/12008.
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Wang, Yue. "Microalgae as the Third Generation Biofuel：Production, Usage, Challenges and Prospects." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-210995.
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Microalgae refer to a kind of autotrophic microorganism with rich nutrition and high photosynthetic utilization degree, which are widely living in the sea and land. Microalgae can be converted into bio energy such as biogas, biodiesel and bio oil. This thesis presents a review on the different cultivation methods and energy conversion techniques of microalgae. Through comparison with other biomass feedstocks, the advantages and disadvantages of microalgae are detailed. Since the large scale of microalgae bioenergy production has not been achieved yet, the commercial production requirements and the sustainability of microalgae are analysed. As a result, high lipid content, less cultivated land use and short life time circle are thought to be the typical advantages of microalgae that it can be considered as a potential substitute of fossil fuel.
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Callens, Cedric Kofi Aurelien. "Third generation of reoxidant for osmium : extension and novel applications." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:5be1ee62-70b1-4643-9707-87de0487278a.
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This thesis describes the development of new osmium-mediated methodologies providing novel applications through the use of a third generation of reoxidant for osmium. Chapter 1, The introduction: Summary of past and present methodologies towards the synthesis of the 1,2 amino alcohol motif. Chapter 2, Intramolecular processes: The studies of the tethered aminohydroxylation (TA) of amide and urea derivatives are being investigated. Chapter 3, Investigations towards an intermolecular process: The transposition of the TA methodology to an intermolecular process and the requirements involved are discussed. The role of acetamide is being investigated. Chapter 4, Successful transition to an intermolecular process: Amino acid derivatives became for the first time possible nitrogen sources and were efficiently employed through osmium-mediated reaction to afford interesting biological scaffolds. Chapter 5, Experimental: Full experimental procedures and characterisation of compounds are reported. References: A complete list of citations employed in the previous five chapters is provided. Appendix: Full documentation of X-ray crystal structures, key NMR spectra and HPLC traces is provided.
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Palsule, Sanjay. "Structure and properties of aerospace molecular composites : third generation polymers." Thesis, Heriot-Watt University, 1994. http://hdl.handle.net/10399/1388.
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Heller, David [Verfasser]. "Structural variant calling using third-generation sequencing data / David Heller." Berlin : Freie Universität Berlin, 2021. http://d-nb.info/122534946X/34.
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Harpel, Kaitlin Gillett. "Imaging of Targeted Lipid Microbubbles using Third Harmonic Generation Microscopy." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/613375.
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The use of receptor-targeted lipid microbubbles imaged by ultrasound is an innovative method of detecting and localizing disease. However, since ultrasound requires a medium between the transducer and the object being imaged, it is impractical to apply to an exposed surface in a surgical setting where sterile fields need be maintained. Additionally, the application of an ultrasound gel to the imaging surface may cause the bubbles to collapse. Multiphoton microscopy (MPM) is an emerging tool for accurate imaging of tissues and cells with high resolution and contrast. We have recently developed a novel method for detecting targeted microbubble adherence to the upregulated plectin-receptor on pancreatic tumor cells using MPM. Specifically, the third-harmonic generation response can be used to detect bound microbubbles to various cell types presenting MPM as an alternative and useful imaging method. This is an interesting technique that can potentially be translated as a diagnostic tool for the early detection of cancer and inflammatory disorders.
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Bly, Elizabeth Ann. "Generation X and the Invention of a Third Feminist Wave." Cleveland, Ohio : Case Western Reserve University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1259803398.
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Thesis (Ph. D.)--Case Western Reserve University, 2010.Title from PDF (viewed 2009-12-30). Department of History. Includes abstract. Includes bibliographical references and appendices. Available online via the OhioLINK ETD Center.
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Lau, Buon Kiong. "Applications of Adaptive Antennas in Third-Generation Mobile Communications Systems." Thesis, Curtin University, 2002. http://hdl.handle.net/20.500.11937/2019.
Full textAbstract:
Adaptive antenna systems (AAS's) are traditionally of interest only in radar and sonar applications. However, since the onset of the explosive growth in demand for wireless communications during the 1990's, researchers are giving increasing attention to the use of AAS technology to overcome practical challenges in providing the service. The main benefit of the technology lies in its ability to exploit the spatial domain, on top of the temporal and frequency domains, to improve on transceiver performance. This thesis presents a unified study on two classes of preprocessing techniques for uniform circular arrays (UCA's). UCA's are of interest because of their natural ability to provide a full azimuth (i.e. 360') coverage found in typical scenarios for sensor array applications, such as radar, sonar and wireless communications. The two classes of preprocessing techniques studied are the Davies transformation and the interpolated array transformations. These techniques yield a mathematically more convenient form - the Vandermonde form - for the array steering vector via a linear transformation. The Vandermonde form is useful for different applications such as direction-of-arrival (DOA) estimation and optimum or minimum variance distortionless response (MVDR) beamforming in correlated signal environment and beampattem synthesis. A novel interpolated array transformation is proposed to overcome limitations in the existing interpolated array transformations. A disadvantage of the two classes of preprocessing techniques for UCA's with omnidirectional elements is the lack of robustness in the transformed array steering vector to array imperfections under certain conditions. In order to mitigate the robustness problem, optimisation problems are formulated to modify the transformation matrices.Suitable optimisation techniques are then applied to obtain more robust transformations. The improved transformations are shown to improve robustness but at the cost of larger transformation errors. The benefits of the robustification procedure are most apparent in DOA estimation. In addition to the algorithm level studies, the thesis also investigates the use of AAS technology with respect to two different third generation (3G) mobile communications systems: Enhanced Data rates for Global Evolution (EDGE) and Wideband Code Division Multiple Access (WCDMA). EDGE, or more generally GSM/EDGE Radio Access Network (GERAN), is the evolution of the widely successful GSM system to provide 3G mobile services in the existing radio spectrum. It builds on the TDMA technology of GSM and relies on improved coding and higher order modulation schemes to provide packet-based services at high data rates. WCDMA, on the other hand, is based on CDMA technology and is specially designed and streamlined for 3G mobile services. For WCDMA, a single-user approach to DOA estimation which utilises the user spreading code and the pulse-shaped chip waveform is proposed. It is shown that the proposed approach produces promising performance improvements. The studies with EDGE are concerned with the evaluation of a simple AAS at the system and link levels.Results from, the system and link level simulations are presented to demonstrate the effectiveness of AAS technology in the new mobile communications system. Finally, it is noted that the WCDMA and EDGE link level simulations employ the newly developed COST259 directional channel model, which is capable of producing accurate channel realisations of macrocell environments for the evaluation of AAS's.
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Lau, Buon Kiong. "Applications of Adaptive Antennas in Third-Generation Mobile Communications Systems." Curtin University of Technology, Australian Telecommunications Research Institute, 2002. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=12983.
Full textAbstract:
Adaptive antenna systems (AAS's) are traditionally of interest only in radar and sonar applications. However, since the onset of the explosive growth in demand for wireless communications during the 1990's, researchers are giving increasing attention to the use of AAS technology to overcome practical challenges in providing the service. The main benefit of the technology lies in its ability to exploit the spatial domain, on top of the temporal and frequency domains, to improve on transceiver performance. This thesis presents a unified study on two classes of preprocessing techniques for uniform circular arrays (UCA's). UCA's are of interest because of their natural ability to provide a full azimuth (i.e. 360') coverage found in typical scenarios for sensor array applications, such as radar, sonar and wireless communications. The two classes of preprocessing techniques studied are the Davies transformation and the interpolated array transformations. These techniques yield a mathematically more convenient form - the Vandermonde form - for the array steering vector via a linear transformation. The Vandermonde form is useful for different applications such as direction-of-arrival (DOA) estimation and optimum or minimum variance distortionless response (MVDR) beamforming in correlated signal environment and beampattem synthesis. A novel interpolated array transformation is proposed to overcome limitations in the existing interpolated array transformations. A disadvantage of the two classes of preprocessing techniques for UCA's with omnidirectional elements is the lack of robustness in the transformed array steering vector to array imperfections under certain conditions. In order to mitigate the robustness problem, optimisation problems are formulated to modify the transformation matrices.Suitable optimisation techniques are then applied to obtain more robust transformations. The improved transformations are shown to improve robustness but at the cost of larger transformation errors. The benefits of the robustification procedure are most apparent in DOA estimation. In addition to the algorithm level studies, the thesis also investigates the use of AAS technology with respect to two different third generation (3G) mobile communications systems: Enhanced Data rates for Global Evolution (EDGE) and Wideband Code Division Multiple Access (WCDMA). EDGE, or more generally GSM/EDGE Radio Access Network (GERAN), is the evolution of the widely successful GSM system to provide 3G mobile services in the existing radio spectrum. It builds on the TDMA technology of GSM and relies on improved coding and higher order modulation schemes to provide packet-based services at high data rates. WCDMA, on the other hand, is based on CDMA technology and is specially designed and streamlined for 3G mobile services. For WCDMA, a single-user approach to DOA estimation which utilises the user spreading code and the pulse-shaped chip waveform is proposed. It is shown that the proposed approach produces promising performance improvements. The studies with EDGE are concerned with the evaluation of a simple AAS at the system and link levels.
Results from, the system and link level simulations are presented to demonstrate the effectiveness of AAS technology in the new mobile communications system. Finally, it is noted that the WCDMA and EDGE link level simulations employ the newly developed COST259 directional channel model, which is capable of producing accurate channel realisations of macrocell environments for the evaluation of AAS's.
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O'Neill, Catherine Anne. "Characterisation of leader peptidase as an antimicrobial target." Thesis, Bangor University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.291667.
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Ciatto, Giovanni. "Third generation neural networks: formalization as timed automata, validation and learning." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/12947/.
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Questa tesi mostra una formalizzazione delle reti neurali spiking ottenuta tramite automi temporizzati. Tali reti, a differenza di quelle di seconda generazione, tengono conto anche della dimensione temporale. Sono mostrate due codifiche, sincrona e asincrona, del modello "leaky integrate and fire": i neuroni sono modellati come automi temporizzati che attendono impulsi su dei canali di ingresso e aggiornano il potenziale in base agli input presenti e passati, modulati dai pesi delle rispettive sinapsi e tanto più influenti quanto più recenti. Se il potenziale supera una certa soglia, l'automa emette un segnale sul canale di uscita. Dopo ogni emissione i neuroni rimangono silenti per un periodo refrattario fissato per poi resettarsi. Nel modello asincrono gli input si assumono molto frequenti ma non possono essere contemporanei. In quello sincrono tutti gli impulsi ricevuti nello stesso periodo di accumulazione sono simultanei. Una rete neurale è ottenuta eseguendo in parallelo più automi che condividono canali opportunamente. Anche le sequenze in input sono specificate tramite automi temporizzati, detti generatori, ottenuti tramite un procedimento automatico, da un linguaggio che modella sequenze di spike e pause. Per il modello sincrono si verifica la capacità di riprodurre alcuni comportamenti noti in letteratura. Esso è poi sfruttato per trovare i pesi sinaptici che permettano ad una rete di riprodurre un comportamento dato, espresso tramite logica temporale. Ciò è ottenuto tramite un algoritmo che identifica gli errori commessi dai neuroni di output e applica delle azioni correttive sulle loro sinapsi in ingresso. Le informazioni sulle azioni correttive adeguate vengono poi propagate all'indietro verso gli altri neuroni della rete. Questo processo è ripetuto fino alla riproduzione del comportamento desiderato. Due gli approcci implementativi presentati: uno basato sulla simulazione e uno basato sul model-checking.
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Urban, Michael Urban Matthias. "Third harmonic generation of high power far infrared radiation in semiconductors /." Lausanne : CRPP, [Centre de recherches en physique des plasmas], Ecole polytechnique fédérale, 1996. http://library.epfl.ch/theses/?nr=1492.
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Vamvaka, Evangelia. "Rice endosperm as a production platform for third-generation HIV microbicides." Doctoral thesis, Universitat de Lleida, 2014. http://hdl.handle.net/10803/285629.
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L’objectiu de la meva tesis doctoral és la producció en l’endosperma de l’arròs d’una tercera generació de microbicides contra el virus de la sida. Durant la meva recerca he utilitzat l’anticòs monoclonal 2G12 i dues proteïnes que neutralitzen el virus de la sida CV-N i GRFT, soles o en combinació, per a descobrir noves estratègies de producció. En la primera part he investigat si podia produir 2G12 a l’endosperma de l’arròs i quins eren els factors que influenciaven la seva producció. En la segona part de la meva tesis he introduït GRFT a l’endosperma de l’arròs i he analitzat si la proteïna expressada tenia activitat neutralitzant del virus de la SIDA. La expressió de GRFT en l’endosperma de l’arròs va ser comparable o inclús en algun cas més alta a GRFT expressada de forma transitòria en tabac. A la tercera part de la meva tesis he investigat si l’endosperma d’arròs seria una plataforma funcional per a la producció de CV-N i si aquesta proteïna tindria capacitat neutralitzant del virus de la sida. Finalment he utilitzat una combinació de microbicides 2G12, CV-N i GRFT per a introduir-les simultàniament a l’endosperma de l’arròs i identificar la millor combinació contra el virus de la sida, i si la co-expresió augmentava el seu efecte neutralitzant. Aquesta es la primera vegada que més d’una proteïna que neutralitzen el virus de la sida son produïdes de forma estable en l’endosperma d’un cereal, obrint un camí nou cap a la producció d’un còctel microbicida per a evitar la transmissió del virus de la sida.El objetivo de mi tesis doctoral es la producción en el endospermo de arroz de una tercera generación de microbicidas contra el virus del SIDA. Durante mi trabajo de investigación utilicé el anticuerpo monoclonal 2G12 y dos proteínas que neutralizan el virus, CV-N y GRFT, solas o en combinación, para explorar diferentes estrategias de producción. En la primera parte de mi tesis investigué si podía producir 2G12 en el endospermo de arroz y cuáles eran los factores que afectaban a su producción. En la segunda parte de mi tesis, he introducido GRFT en el endospermo de arroz y he investigado si la proteína producida tenía actividad neutralizante del virus del SIDA. La expresión de GRFT en el endospermo del arroz fue comparable o incluso en algún caso más alta a GRFT producida de forma transitoria en tabaco. En la tercera parte de mi tesis he investigado si el endospermo de arroz sería una plataforma funcional para la producción de CV-N y si esta proteína sería capaz de neutralizar el virus del sida. La proteína Finalmente he utilizado una combinación de microbicidas 2G12, CV-N y GRFT para introducirlos simultáneamente en el endospermo de arroz e identificar la mejor combinación contra el virus del sida, y si la co-expresión potenciaba su efecto neutralizante. La combinación Esta es la primera vez que más de una proteína que neutraliza el virus del sida es producida de forma estable en el endospermo de un cereal, abriendo un nuevo camino hacia la producción de un cóctel microbicida para evitar la transmisión del virus del sida.
The focus of this thesis is the production of third-generation HIV microbicides in rice cells. I used one monoclonal antibody (2G12) and two anti-HIV proteins (CV-N and GRFT) alone or in combination, to explore different strategies to produce an efficient microbicide against HIV. The first part of my PhD thesis was to test whether rice endosperm can function as a platform for the production of 2G12 and to gain insight into the factors that affect the production and functional efficacy of neutralizing antibodies in plants. The human mAb2G12 was expressed successfully into rice endosperms as an aglycosylated form. In the second part of the thesis I introduced GRFT into rice endosperm and I tested whether the rice-derived GRFT protein retains its potent HIV-neutralizing activity. GRFT was successfully expressed in rice endosperm resulting in yields comparable or even higher to GRFT produced transiently in tobacco and other recombinant proteins. In the third part of my thesis I explored whether rice endosperm could function as a production platform to produce CV-N and I evaluated whether the rice-derived CV-N could neutralize efficiently the HIV virus. Finally I used a combinatorial approach introducing the 2G12, CV-N and GRFT into rice cells to identify the best combination against HIV, and whether their co-expression enhanced their effect. This is the first time that more than one protein against HIV is stable expressed into endosperm opening a new way for the production of a microbicide cocktail for the prevention of HIV transmission.
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Kivistö, K. (Kari). "A third generation object-oriented process model:roles and architectures in focus." Doctoral thesis, University of Oulu, 2000. http://urn.fi/urn:isbn:9514258371.
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Abstract
This thesis examines and evaluates the Object-Oriented Client/Server
(OOCS)
model, a process model that can be used when IT organizations develop
object-oriented client/server applications. In particular, it defines the roles
in the development team and combines them into the process model. Furthermore,
the model focuses on the client/server architecture, considering it explicitly.
The model has been under construction for several years and it has been tested
in a number of industrial projects. Feedback from practice has thus been an
important source when the model has been evolving into its current form. Another
source for evolution has been other process models and technical progress in
this field. This thesis reveals the theoretical and practical aspects that have
influenced the model's characteristics and developmnt.
The object-oriented paradigm has been the driving force when creating the
OOCS
model. The first object-oriented development models were, however, both
inadequate and contradictory to each other. The OOCS model utilizes the best
practices from these early models. The model also defines artifacts to be
delivered in each phase. The artifacts are synchronized with the Unified
Modeling Language (UML), a new standard modeling notation.
From the very beginning the OOCS model has included a strong client/server
viewpoint, which is not stated so clearly in other object-oriented models. A
three-tier division of the application (presentation, business logic, data
management) can be found in each phase. This division has become crucial in
recent years, when applications have been built on distributed architecture.
The team-based roles included in the model are based on the work of a few other
researchers, although this topic has not gained the importance it should have
had. Namely, it is people that develop the application and their involvement in
the process should be stated explicitly. The roles of the developers are closely
connected to the OOCS process model via the concept of activities included in
the model. The roles concentrate mainly on project members, but company-level
aspects have also been considered.
This thesis summarizes the work carried out in the last five years. It
shows how
the model has evolved in practice and how other models have contributed to it.
The team-based OOCS model is in use in some IT organizations. The cases
presented in this thesis illustrate how to adapt the model into specific
organizational needs.
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Bortnik, Helen Martha. "Acculturation and family values : first, second, and third generation Russian immigrants." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/30374.
Full textAbstract:
This study compared acculturation and familism of first, second, and third generation Russian immigrants. A sample of 71 included 22 first generation, 30 second generation, and 18 third generation male and female Russian immigrants from Vancouver, B.C., ranging in age from 19 to 82. Questionnaires mailed included demographic items, the Bardis Familism Scale (Bardis, 1959), and a revised Short Acculturation Scale (Marin, Sabogal, Marin, Otero-Sabogal, and Perez-Stable, 1987). Results of one-way ANOVA's revealed that there were no significant differences in scores on the Bardis Familism Scale between any of the three generations, contrary to previous studies with other immigrant groups. However, second and third generation subjects scored significantly higher on the acculturation scale than first generation ones, [F (2, 67) =25.00, p = .001]. A high level of Russian speaking ability and a low education level were associated with higher familism scores, and greater length of time in Canada was associated with higher acculturation scores. Since scores on the acculturation scale were consistent with those obtained in studies with other immigrant groups, this study provides support for the validity of this scale for Russian immigrants.Education, Faculty of
Educational and Counselling Psychology, and Special Education (ECPS), Department of
Graduate
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Mandes, Alejandro Salvador. "Ministry to second, third and fourth generation Latinos in North America." Theological Research Exchange Network (TREN), 2007. http://www.tren.com/search.cfm?p001-1191.
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Steinlechner, Jessica [Verfasser]. "Optical absorption measurements for third generation gravitational wave detectors / Jessica Steinlechner." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2013. http://d-nb.info/103667200X/34.
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Barry, Mudar A. O. "Architectures for supporting Internet mobility beyond third generation mobile access networks." Thesis, University of Kent, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.410920.
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Tafazolli, Rahim. "Multiple access protocols for third generation cellular mobile/personal communication systems." Thesis, University of Surrey, 1995. http://epubs.surrey.ac.uk/844475/.
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This thesis is concerned with provision of multimedia services in cellular mobile/personal communication systems. It is a recognised fact that the success of mobile radio systems, in keeping a competitive edge with fixed telecommunication systems, depends on their capability to support as many services as possible and with comparative quality to that offered by the fixed networks. The first generation cellular systems (analogue) and second generation mobile communication systems (digital) were all designed primarily to support telephony services. Now there are worldwide standards activities in ETSI and ITU working towards a third generation system (digital) which aims to support services of up to 2Mbps. ETSI and ITU systems are called Universal Mobile Telecommunication System (UMTS) and Future Public Land Mobile Telecommunication System (FPLMTS), which has recently been named International Mobile Telecommunications for year 2000 at 2000 MHz or (IMT-2000) respectively. These systems are to operate, in allocated WARC'92 frequency bands between 1.885 GHz to 2.5 GHz. This thesis is aimed at an evaluation of possible potentials offered by the second generation systems, particularly GSM, and to propose new protocols for supporting data services whilst at the same time increasing spectral efficiency of the system and keeping intact the offered quality of telephony services. It must be emphasised that, the support of low bit rate data services, if not carefully incorporated, could result in inefficient use of the scarce radio spectrum. Therefore, major concern in this work is with accommodation of the low bit rate data services. Higher bit rate services (higher than voice codec rates) can be accommodated differently. Possible solutions are also proposed. This thesis is structured in a way that, hopefully, provides a logical approach to the problem and eventually to the proposed solutions. The introduction chapter starts with a brief account of the services envisaged for the third generation systems. To be able to evaluate the capability and suitability of already existing multiple access protocols and multiple access schemes, in chapter 2, a list of performance criteria is derived. As a result of these comparisons, TDMA as an access scheme and the GSM system were selected for further evaluation. In chapter 3, all the relevant aspect of the GSM system, for this research, are presented. Chapter 4, deals mainly with all of the characteristics of speech; discusses and tabulates all the possible parameters which can affect the speech quality, and that are essential to be taken account of when designing a telephony communication system. As a result of this, a model for speech is derived and adopted for further analysis. In chapter 5 all the currently proposed reservation-based multiple access protocols, suitable for statistical multiplexing of voice and data services are critically discussed. A new and generic mathematical technique, based on queuing theory, is derived and promising protocols such as PRMA and PRMA++ (candidate access protocols for the third generation mobile system) are evaluated. Detailed analysis of the PRMA protocol leads to new modifications which greatly enhances all of the statistics of PRMA and its derivatives. In chapter 5, it is also shown that PRMA increases system capacity at the cost of service quality. The present TDMA access protocol used in GSM was realised to be too rigid to efficiently support data services, especially low rate data services, so this research work was mainly directed to including some flexibility into GSM access protocols, without sacrificing voice service quality. Finally four novel protocols are identified and in chapter 6, their performance is thoroughly evaluated for mixed services in the GSM TDMA frame structure. Alternative frame structures are also investigated which can support even higher bit rate data services than those supportable within the current GSM frame structure. Finally, chapters 7 and 8, respectively, deal with conclusions of this research work and the list of references used in this investigation.