Дисертації з теми "Communications and networks technologies"
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Wu, Yue. "Advanced technologies for device-to-device communications underlaying cellular networks." Thesis, University of Sheffield, 2016. http://etheses.whiterose.ac.uk/15391/.
Повний текст джерелаChowdhury, Arshad M. "Optical Label Switching Technologies for Optical Packet Switched Networks." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/14047.
Повний текст джерелаChatterjee, Shubhajeet. "On Enabling Virtualization and Millimeter Wave Technologies in Cellular Networks." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/100596.
Повний текст джерелаDoctor of Philosophy
In cellular networks, mobile network operators (MNOs) have been sharing resources (e.g., infrastructure and spectrum) as a solution to extend coverage, increase capacity, and decrease expenditures. Recently, due to the advent of 5G wireless services with enormous coverage and capacity demands and potential revenue losses due to over-provisioning to serve peak demands, the motivation for sharing and virtualization has significantly increased in cellular networks. Through wireless network virtualization (WNV), wireless services can be decoupled from the network resources so that various services can efficiently share the resources. At the same time, utilization of the large bandwidth available in millimeter wave (mmW) frequency band would help to overcome ongoing spectrum scarcity issues. However, due to the inherent features of cellular networks, i.e., the uncertainty in user equipment (UE) locations and channel conditions, enabling WNV and mmW communications in cellular networks is a challenging task. Specifically, we need to build the virtual networks in such a way that UE demands are satisfied, isolation among the virtual networks are maintained, and resource over-provisioning is minimized in the presence of uncertainty in UE locations and channel conditions. In addition, the mmW channels experience higher attenuation and blockage due to their small wavelengths compared to conventional sub-6 GHz channels. To compensate for the high pathloss, mmW systems typically use beamforming techniques. The directional communication in the presence of uncertainty in UE locations and channel conditions, make maintaining connectivity and performing initial access and cell discovery challenging. Our goal is to address these challenges and develop optimization frameworks to efficiently enable virtualization and mmW technologies in cellular networks.
Oliveira, Rúben Pedrosa. "Sensor networks with multiple technologies: short and long range." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/22735.
Повний текст джерелаLow-Power Wide Area Networks (LPWANs) are one set of technologies that are growing in the eld of the Internet of Things (IoT). Due to the long range capabilities and low energy consumption, Low-Power Wide Area Networks (LPWANs) are the ideal technologies to send small data occasionally. With their unique characteristics, LPWANs can be used in many applications and in di erent environments such as urban, rural and even indoor. The work developed in this dissertation presents a study on the LPWAN LoRa technology, by testing and evaluate its range, signal quality properties and its performance in delivering data. For this, three distinct scenarios are proposed and tested. The inclusion of LoRa in a multi-technology data gathering platform is the key objective of this dissertation. For this it is proposed: (1) an organization based in clusters of sensor nodes; (2) a Media Access Control (MAC) protocol to provide e cient communications through the LoRa technology; and nally, (3) a Connection Manager that is capable of managing the di erent available technologies in the sensor nodes and that is able to adapt its actions according to the acquired data type is proposed. The performed tests aim to perceive which type of parameters can in uence the performance of the overall proposed solution, as well as the advantages of a multi-technology approach in a data gathering platform.
Low-Power Wide Area Networks (LPWANs) são um conjunto de tecnologias em crescimento na área da Internet of Things (IoT). Devido ás suas capacidades de comunicar a longo alcance e de baixo consumo energético, as LPWANs apresentam-se como a tecnologia ideal para o envio ocasional de pequenas porções de dados. Ao possuírem características únicas, as LPWANs podem ser usadas em diversas aplicações e em diferentes ambientes, sejam eles urbanos, rurais ou interiores. O trabalho desenvolvido nesta dissertação apresenta um estudo acerca da tecnologia Long Range (LoRa), uma LPWAN, testando e avaliando o seu alcance, a qualidade do sinal e o desempenho na entrega de dados. Para isso, três cenários distintos são propostos e testados. A inclusão de LoRa numa plataforma de aquisição de dados com múltiplas tecnologias e um dos objectivos chave desta dissertação. Para isso, são propostas: (1) uma organização baseada em clusters de sensores; (2) um protocolo de controlo de acesso ao meio (MAC) para permitir que as comunicações através de LoRa sejam eficientes; e finalmente, (3) um gestor de conectividade com capacidade de gerir as diferentes tecnologias disponíveis nos sensores e que seja capaz de agir consoante o tipo de dados adquiridos. Os testes efectuados tem como objectivo perceber que tipo de parâmetros podem influenciar o desempenho global da soluçao proposta, bem como as vantagens de usar uma abordagem baseada em múltiplas tecnologias numa plataforma de aquisição de dados.
Sato, Ken-ichi, and Hiroshi Hasegawa. "Optical Networking Technologies That Will Create Future Bandwidth-Abundant Networks [Invited]." IEEE, 2009. http://hdl.handle.net/2237/13919.
Повний текст джерелаQin, Xiaoqi. "Exploring Performance Limits of Wireless Networks with Advanced Communication Technologies." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/73215.
Повний текст джерелаPh. D.
Alaoui, Nabih. "Cooperative Communications In Mobile Ad hoc NETworks." Limoges, 2013. http://aurore.unilim.fr/theses/nxfile/default/16707b62-af2a-425b-b97b-ee0f900ae15d/blobholder:0/2013LIMO4035.pdf.
Повний текст джерелаThe work done in this study focuses on communication and data transmission in the context of sensor networks. To improve the reliability of transmission, relays are inserted between the sensors and the destination in order to correct errors in transmissions using LDPC codes. The architecture is optimized thanks to the block codes but also to the error detection protocols and the use of a combination of the error correction and detection. Another interesting way to improve performances is to use multiple antenna systems. Energy efficiency is evaluated in the protocols studied and the solutions proposed. Besides, a joint optimization of channel coding and physical network coding is proposed in this paper
Naik, Gaurang Ramesh. "Coexistence of Vehicular Communication Technologies and Wi-Fi in the 5 and 6 GHz bands." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/100905.
Повний текст джерелаDoctor of Philosophy
Wireless networks have become ubiquitous in our lives today. Whether it is cellular connectivity on our mobile phones or access to Wi-Fi hotspots on laptops, tablets, and smartphones, never before has wireless communication been as integral to our lives as it is today. In many wireless communication systems, wireless devices operate by sending signals to and receiving signals from a central entity that connects to the wired Internet infrastructure. In the case of cellular networks, this entity is the cell tower deployed by the operators (such as ATandT, Verizon, etc. in the US), while the Wi-Fi router deployed in homes and offices plays this role in Wi-Fi networks. There is also another class of wireless systems, where wireless devices communicate with each other without requiring to communicate with any central entity. An example of such a distributed communication system---which is fast gaining popularity---is vehicular communication networks. End-user devices (e.g. cellphone, laptop, tablet, or a vehicle) can communicate with each other or the central entity only if they are both tuned to the same frequency channel. This channel can lie anywhere within the radio frequency spectrum, but some frequency channels (the collection of channels is referred to as frequency bands) are more favorable—--in terms of how far the signal sent over these channels can reach—--than others. Another dimension to these frequency bands is the licensing mechanism. Not all frequency bands are free to use. In fact, most frequency bands in the US and other parts of the world are licensed by the regional regulatory agencies. The most well-known example of this licensing framework is the cellular network. Cellular operators spend large amounts of money (to the tune of billions of dollars) to gain the privileges of exclusively operating in a given frequency band. No other operator or wireless device is then allowed to operate in this band. Without any external interfering wireless device, cellular operators can guarantee a certain quality of service that is provided to its customers. Thus, the benefits of using licensed frequency bands are obvious but these bands and their associated benefits come at a high price. An alternative to licensed frequency bands are the unlicensed ones. As the name suggests, unlicensed frequency bands are those where any two or more wireless devices can communicate with each other (subject to certain rules) without having to pay any licensing fees. Unsurprisingly, because there is no limit to who or how many devices can communicate over these bands, wireless devices in these bands frequently experience external interference, which manifests to the end-user in terms of interruption of service. The best example of a wireless technology that uses unlicensed bands is Wi-Fi. One of the greatest advantages of Wi-Fi networks is that anyone can purchase a Wi-Fi router and deploy it within their homes or offices—--flexibility not afforded by licensed bands. However, this very flexibility and ease-of-use can sometimes contribute negatively to Wi-Fi performance. Arguably, we have all faced scenarios where the performance of Wi-Fi is poor. This is most likely to happen in scenarios where there are hundreds (or even thousands) of neighboring Wi-Fi devices, such as at stadiums, railway stations, concerts, etc. Based on our discussions above, it is clear as to why Wi-Fi performance suffers in such scenarios. Thus, although unlicensed bands are lucrative in terms of low-cost, and ease of use, there is no guarantee on how good a voice/video call or a video streaming session conducted over Wi-Fi will be. The above problem is well-known and well-researched. Regulators, researchers, and service providers actively seek solutions to offer better performance over unlicensed bands. An obvious solution is to make more unlicensed bands available; if all neighboring Wi-Fi users communicate with their respective routers on different channels, everyone could communicate interference-free. The problem, however, is that frequency bands are limited. Even more limited are those bands that support wireless communications over larger distances. Another solution is to improve the wireless technology—if a Wi-Fi device can more efficiently utilize the channel, its performance is likely to improve. This fact has driven the constant evolution of all wireless technologies. However, there are fundamental limits to how much a frequency channel can be exploited. Therefore, in recent years, stakeholders have turned to spectrum sharing. Even though a wireless network may possess an exclusive license to operate on a given frequency band, its users do not use the band everywhere and at all times. Then why not allow unlicensed wireless devices to operate in this band at such places and times? This is precisely the premise of spectrum sharing. In this dissertation, we look at the problem of coexistence between wireless technologies in the 5 GHz and 6 GHz bands. These two bands are extremely lucrative in terms of their relatively favorable propagation characteristics (i.e., their communication range) and the abundance of spectrum therein. Consequently, these bands have garnered considerable attention in recent years with the objective of opening these bands up for unlicensed services. However, the 5 GHz and 6 GHz bands are home to several licensed systems, and the performance of these systems cannot be compromised if unlicensed operations are allowed. Significant activity has taken place since 2013 concerning new technologies being developed, new spectrum sharing scenarios being proposed, and new rules being adopted in these two bands. We begin the dissertation by taking a comprehensive look at these issues, describing the various coexistence scenarios, surveying the existing literature, describing the major challenges, and providing directions for potential research. Next, we look at three coexistence problems in detail: (i) coexistence of dedicated short range communications (DSRC) and Wi-Fi, (ii) coexistence of cellular V2X (C-V2X) and Wi-Fi, and (iii) coexistence of 5G New Radio Unlicensed (5G NR-U) and Wi-Fi. The former two scenarios involve the coexistence of Wi-Fi with a vehicular communication technology (DSRC or C-V2X). These scenarios arose due to considerations in the US and Europe to allow Wi-Fi operations (on an unlicensed secondary basis) in the spectrum that was originally reserved for vehicular communications. Our work shows that because DSRC and Wi-Fi are built on top of fundamentally similar protocols, they are, to an extent, compatible with each other, and coexistence between these two technologies can be achieved by relatively simple modifications to the Wi-Fi protocol. However, C-V2X, owing to its inheritance from the cellular LTE, is not compatible with Wi-Fi. Consequently, significant research is required if the two technologies are to share the spectrum. On the other hand, in the coexistence of 5G NR-U and Wi-Fi, we focus on the operations of these two technologies in the 6 GHz bands. NR-U is a technology that is built atop the 5G cellular system, but is designed to operate in the unlicensed bands (in contrast to traditional cellular systems which only operate in licensed bands). Although these two technologies can coexist in the 5 GHz and 6 GHz bands, we restrict our attention in this dissertation to the 6 GHz bands. This is because the 6 GHz bands are unique in that the entire range of the 6 GHz bands were opened up for unlicensed access all at once recently, and no Wi-Fi or NR-U devices currently operate in these bands. As a result, we can learn from the mistakes made in the 5 GHz bands, where a vast majority of today's Wi-Fi networks operate. Our work shows that, indeed, we can take decisive steps---such as disabling certain Wi-Fi functions---in the 6 GHz bands, which can facilitate better coexistence in the 6 GHz bands. Finally, in the course of identifying and tackling the various coexistence scenarios in the 5 GHz and 6 GHz bands, we identify some open issues in the performance of new wireless technologies designed to operate in these bands. Specifically, we highlight the need to better understand and characterize the performance of Multi User Orthogonal Frequency Division Multiple Access (MU OFDMA), a feature common in cellular networks but newly introduced to Wi-Fi, in the upcoming Wi-Fi 6 generation of devices. We propose and evaluate an analytical model for the same. We also characterize the performance of Multi Link Aggregation---which a novel feature likely to be introduced in future Wi-Fi 7 devices---that is aimed at reducing the worst-case delay experienced by Wi-Fi devices in dense traffic conditions. Additionally, we identify an issue in the performance of the distributed operational mode of C-V2X. We show that packet re-transmissions, which is a feature aimed at improving the performance of C-V2X, can have a counter-productive effect and degrade the C-V2X performance in certain environments. We address this issue by proposing a simple, yet effective, re-transmission control mechanism.
Ge, Feng. "Software Radio-Based Decentralized Dynamic Spectrum Access Networks: A Prototype Design and Enabling Technologies." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/29981.
Повний текст джерелаPh. D.
Shahpari, Ali. "Next generation optical access networks : technologies and economics." Doctoral thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/14857.
Повний текст джерелаThe work presented herein, studies Next Generation Optical Access Networks (NG-OAN) economically (e.g. energy consumption) and technologically (e.g. rate, reach and dedicated/shared bandwidth). The work is divided into four main topics: energy efficiency in optical access architectures, novel spectrally efficient Long-Reach Passive Optical Networks (LR-PON), crosstalk impacts in heterogeneous and homogenous access networks and hybrid optical wireless transmissions. We investigate the impact of user profiles, optical distribution network topologies and equipment characteristics on resource sharing and power consumption in LR-PON. To have a clear vision on the energy consumption evolution of each part of NG-OAN, a model is proposed to evaluate the energy efficiency of optical access technologies. A spectrally efficient bidirectional Ultra-Dense Wavelength Division Multiplexing (UDWDM) PON architecture is developed using Nyquist shaped 16-ary quadrature amplitude modulation, offering up to 10 Gb/s service capabilities per user or wavelength. Performance of this system in terms of receiver sensitivity and nonlinear tolerance under different network transmission capacity conditions are experimentally optimized. In bi-directional transmis-sion, using frequency up/down-shifting of Nyquist pulse shaped signal from optical carrier, a full bandwidth allocation and easy maintenance of UDWDM networks as well as reduction of Rayleigh back-scattering are achieved. Moreover, self-homodyne detection is used to relax the laser linewidth requirement and digital signal processing complexity at the optical network unit. Simplified numerical model to estimate the impact of Raman crosstalk of multi-system next generation PONs in video overlay is proposed. Coexistence of considered G.98X ITU-T series and coherent multi-wavelength systems is considered and assessed. Additionally, the performances of bidirectional hybrid optical wireless coherent PONs over different optical distribution network power budgets and hybrid splitting ratios are evaluated.
O trabalho aqui apresentado estuda redes óticas de acesso de próxima geração (NG-OAN) nas vertentes económica (consumo de energia) e tecnológica (taxa, alcance e largura de banda dedicada/partilhada). O trabalho está dividido em quatro grandes temas de investigação: a eficiência energética em arquiteturas de acesso ótico, as redes óticas passivas de longo alcance (LR-PON) com nova eficiência espetral, o impacto da diafonia em redes de acesso heterogéneas e homogéneas e as transmissões ópticas híbridas com tecnologias sem fio. Investiga-se o impacto dos perfis dos utilizadores, as tipologias da rede de distribuição ótica, as características do equipamento de partilha de recursos e o consumo de energia em LR-PON. Para se ter uma visão clara sobre o consumo de energia de cada parte das NG-OAN, é proposto um modelo para avaliar a eficiência energética das tecnologias de acesso óticas. Desenvolve-se uma arquitetura PON bi-direcional com elevada eficiência espetral, recorrendo a multiplexagem por divisão de comprimento de onda ultra-densa (UDWDM), modulação de amplitude em quadratura com formato de impulso de Nyquist, oferecendo até 10 Gb/s por utilizador/comprimento de onda. O desempenho deste sistema em termos de sensibilidade do recetor e da tolerância à resposta não linear do canal de comunicação, sob diferentes condições de transmissão, é avaliado experimentalm-ente. Em transmissão bi-direcional, utilizando desvio de frequência (cima/baixo) do impulso com formato de Nyquist relativo à portadora ótica conseguiu-se uma alocação de largura de banda completa e uma manutenção mais simplificada de redes UDWDM, bem como a redução do espalhamento de Rayleigh. Além disso, a deteção auto-homodina é usada para relaxar o requisito de largura de linha do laser e a complexidade do processamento digital de sinal nas unidades da rede ótica. Propõe-se um modelo numérico simplificado para estimar o impacto da diafonia de Raman em sistemas PON de próxima geração, com sobreposição do sinal de vídeo. É analisada a coexistência da série G.98X ITU-T e são considerados e avaliados sistemas coerentes multi-comprimento de onda. Adicionalmente avaliam-se os desempenhos de PONs bi-direcionais híbridas, considerando tecnologia coerente e propagação por espaço livre, para diferentes balanços de potência e taxas de repartição na rede ótica de distribuição.
Saleh, Mohammad. "Secure communications in wireless networks for biomedical EEG sensor networks applications." Thesis, Bourgogne Franche-Comté, 2018. http://www.theses.fr/2018UBFCA024/document.
Повний текст джерелаThe general framework of the thesis concerns sensor networks and the privacy protocols for wireless communications in the implementation of reliable healthcare systems. More precisely, it presents a novel biomedical wireless sensor Network monitoring system, as a predictor and advance sensitive portable electroencephalogram (EEG). The EEG wireless sensor network proposed to monitor spontaneous brain waves, including normal and abnormal waves, for the patients suffering from different types of epilepsy. The biomedical epilepsy wireless sensor Network monitoring system (WSN-EEG) read’s signals from a wireless sensor network on the patient scalp, and filter these signals to run parallel data processing for the brain waves. However, the predicting procedure for the severity of the forthcoming epileptic attack based on, a proposed mathematical model, which analyses the abnormality in the brain waves and alerts by giving signals for the patient. This method can save many patients by predicting the seizure before it occurs and helps them from different injuries and risky behavior arising during epilepsy attack. In addition, the proposed approaches can use the patient data for further medical diagnosis measures. Another approach is proposed as a learning-based approach for prediction using Feed Forward Neural Network (FFNN) for the alert system. The research used the IEEE802.11n as a communication method for the wireless sensor networks and measure the IEEE802.11n security performances as privacy protocol for data transmission of the proposed systems. The measurements indicated the calibration of the prediction algorithms to take account of the delays introduced by the security of the communications in the data transmission and seizure prediction which might significantly reduce prediction time and delay the alert signals
Abboud, Samira. "Study and improvement of long range communication technologies for wireless sensor networks." Thesis, Université Clermont Auvergne (2017-2020), 2020. http://www.theses.fr/2020CLFAC028.
Повний текст джерелаThe progress in low-energy, low-cost communication technologies have revolutionized remote sensing and monitoring applications. Internet of Things (IoT) has promised an ecosystem of connected devices across a wide range of applications such as in smart cities.Currently, many competing standards and technologies are attempting to seize the IoT, particularly in the area of remote sensing and communication technologies. LoRa (Long Range) is one of those technologies that is gaining popularity and attraction in the Wireless Sensor Networks (WSN) applications. The ability to make long-distance communications with relatively simple nodes, minimal infrastructure, reduced power requirements, and the use of unlicensed ISM bands provides a significant competitive advantage. Although the communication range in LoRa can exceed 15 kilometers in line of sight, the maximum bit rate that can be achieved is limited to few kilobits per second. Additionally, when a collision occurs in LoRa, the throughput is further reduced due to frame losses and retransmissions. The work of this thesis deals with the problem of collisions in LoRa that may occur under heavy load, and which degrade the performance of the network.First, we consider the context for LoRaWAN uplink communications. We study the context of fully synchronized colliding LoRa signals, where each end-device has to retransmit its entire colliding frame after a collision occurs in LoRa. This behavior decreases the overall throughput, and increases the energy consumption of the end-devices, and the delay of the frames. Therefore, in order to mitigate the damaging effects of collisions, we proposed a decoding algorithm to resolve synchronized colliding LoRa signals, in a saturated and confirmed network traffic. We substituted the conventional retransmission model of LoRa by having end-devices transmitting bitmaps instead of retransmitting whole frames to determine the correct symbols of each colliding frame. Our algorithm was able to significantly improve the overall throughput of the LoRaWAN MAC layer based on LoRa, and to decrease the energy consumption of the transmitters and the delay of the frames.Second, we consider the context for LoRaWAN downlink communications. We noticed that the downlink in LoRa is a bottleneck. Hence, we worked on the gateway selection by the network server and its impact on the throughput, the energy consumption and the delay. We studied three types of gateway deployment and we show that the system performance depends on this deployment. We showed that balancing the number of end-devices per gateway (also known as load) improves the throughput compared to choosing the gateway with the highest signal quality. Moreover, we showed that combining load and signal quality does not further improve the throughput. In addition, we showed that choosing the gateway with the highest signal quality decreases the delay and energy consumption compared to choosing the gateway with the lowest load
Dhar, Tushar. "Communications network technologies for monitoring and control of power supply systems in remote areas." Thesis, Queensland University of Technology, 1998.
Знайти повний текст джерелаDe, Araujo Marques Leão Lucas Augusto. "Optimization of Communications in Multi-Sink Wireless Sensor Networks." Thesis, Bourgogne Franche-Comté, 2018. http://www.theses.fr/2018UBFCD073.
Повний текст джерелаThe conception of a wireless sensor network may present numerous challenges, such as scalability, reliability, longevity and timeliness. The existence of multiple sinks may increase the network reliability and facilitates the scalability. However, this improvement is dependent on the routing approach, that must be tailored to help achieving the desired performance goals.From this perspective, the objective of this work is to find ways of optimizing the communication in multi-sink wireless sensor networks considering the problems related to the scalability, longevity (network lifetime), reliability (packet delivery) and timeliness (latency). We investigate the trades among data delivery time and energy consumption as key metrics for communication quality and efficiency. For that matter, we propose different routing algorithms, covering all three main communciations schemes (unicast, anycast and multicast).The executed simulations show that our approaches are capable of optimizing the communication, especially in terms of latency and network lifetime. Experiments on the FIT IoT-Lab platform also provide meaningful insights of the performance of our multicast solution in real environment condition
Muzaffar, Raheeb. "Routing and video streaming in drone networks." Thesis, Queen Mary, University of London, 2017. http://qmro.qmul.ac.uk/xmlui/handle/123456789/24713.
Повний текст джерелаHe, Chao. "Improving System Performance in Cellular and WBAN Networks via User-Specific QoS and MIMO In Vivo Technologies." Scholar Commons, 2015. https://scholarcommons.usf.edu/etd/5496.
Повний текст джерелаSarr, Ndéye Bineta. "Communications protocols for wireless sensor networks in perturbed environment." Thesis, Poitiers, 2019. http://www.theses.fr/2019POIT2255/document.
Повний текст джерелаThis thesis is mainly in the Smart Grid domain. SGs improve the safety of electrical networks and allow a more adapted use of electricity storage, available in a limited way. SGs also increase overall energy efficiency by reducing peak consumption. The use of this technology is the most appropriate solution because it allows more efficient energy management. In this context, manufacturers such as Hydro-Quebec deploy sensor networks in the nerve centers to control major equipment. To reduce deployment costs and cabling complexity, the option of a wireless sensor network seems the most obvious solution. However, deploying a sensor network requires in-depth knowledge of the environment. High voltages substations are strategic points in the power grid and generate impulse noise that can degrade the performance of wireless communications. The works in this thesis are focused on the development of high performance communication protocols for the profoundly disturbed environments. For this purpose, we have proposed an approach based on the concatenation of rank metric and convolutional coding with orthogonal frequency division multiplexing. This technique is very efficient in reducing the bursty nature of impulsive noise while having a quite low level of complexity. Another solution based on a multi-antenna system is also designed. We have proposed a cooperative closed-loop coded MIMO system based on rank metric code and max-dmin precoder. The second technique is also an optimal solution for both improving the reliability of the system and energy saving in wireless sensor networks
Twele, Nombulelo. "A feasibility study of wireless network technologies for rural broadband connectivity." Thesis, University of Fort Hare, 2013. http://hdl.handle.net/10353/d1016167.
Повний текст джерелаWalker, Geoffrey. "Communities of practice, networks & technologies : the dynamics of knowledge flows within third sector organisations in the North East of England." Thesis, Northumbria University, 2008. http://nrl.northumbria.ac.uk/3385/.
Повний текст джерелаAguilar, Teck. "Vers un protocole de routage géographique avec contention et communications coopératives pour les réseaux de capteurs." Phd thesis, Institut National des Télécommunications, 2010. http://tel.archives-ouvertes.fr/tel-00612332.
Повний текст джерелаDab, Boutheina. "Optimization of routing and wireless resource allocation in hybrid data center networks." Thesis, Paris Est, 2017. http://www.theses.fr/2017PESC1068/document.
Повний текст джерелаThe high proliferation of smart devices and online services allows billions of users to connect with network while deploying a vast range of applications. Particularly, with the advent of the future 5G technology, it is expected that a tremendous mobile and data traffic will be crossing Internet network. In this regard, Cloud service providers are urged to rethink their data center architectures in order to cope with this unprecedented traffic explosion. Unfortunately, the conventional wired infrastructures struggle to resist to such a traffic growth and become prone to serious congestion problems. Therefore, new innovative techniques are required. In this thesis, we investigate a recent promising approach that augments the wired Data Center Network (DCN) with wireless communications. Indeed, motivated by the feasibility of the new emerging 60 GHz technology, offering an impressive data rate (≈ 7 Gbps), we envision, a Hybrid (wireless/wired) DCN (HDCN) architecture. Our HDCN is based on i) Cisco’s Massively Scalable Data Center (MSDC) model and ii) IEEE 802.11ad standard. Servers in the HDCN are regrouped into racks, where each rack is equipped with a: i) Ethernet top-of-rack (ToR) switch and ii) set of wireless antennas. Our research aims to optimize the routing and the allocation of wireless resources for inter-rack communications in HDCN while enhancing network performance and minimizing congestion. The problem of routing and resource allocation in HDCN is NP-hard. To deal with this difficulty, we will tackle the problem into three stages. In the first stage, we consider only one-hop inter-rack communications in HDCN, where all communicating racks are in the same transmission range. We will propound a new wireless channel allocation approach in HDCN to hardness both wireless and wired interfaces for incoming flows while enhancing network throughput. In the second stage, we deal with the multi-hop communications in HDCN where communicating racks can not communicate in one single-hop wireless path. We propose a new approach to jointly route and allocate channels for each single communication flow, in an online way. Finally, in the third stage, we address the batched arrival of inter-rack communications to the HDCN so as to further optimize the usage of wireless and wired resources. For that end, we propose: i) a heuristic-based and ii) an approximate, solutions, to solve the joint batch routing and channel assignment. Based on extensive simulations conducted in QualNet simulator while considering the full protocol stack, the obtained results for both real workload and uniform traces, show that our proposals outperform the prominent related strategies
Boyle, Alexandra. "Exploring the emotional geographies of communication technology use among older adults in contemporary London." Thesis, Queen Mary, University of London, 2017. http://qmro.qmul.ac.uk/xmlui/handle/123456789/25808.
Повний текст джерела李淑明 and Shuk-ming Selina Li. "The impact of groupware on organizational communication: an examination of group decision-making performance andoutcomes with the support of computer-based communication technologies." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31269047.
Повний текст джерелаBauduin, Marc. "Equalization of Non-linear Satellite Communication Channels using Echo State Networks." Doctoral thesis, Universite Libre de Bruxelles, 2016. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/239317.
Повний текст джерелаDoctorat en Sciences de l'ingénieur et technologie
info:eu-repo/semantics/nonPublished
Smoreda, Zbigniew. "Sociabilités ordinaires, réseaux sociaux et médiation des technologies de communication." Phd thesis, Université Paris-Est, 2008. http://tel.archives-ouvertes.fr/tel-00469439.
Повний текст джерелаLi, Shuk-ming Selina. "The impact of groupware on organizational communication : an examination of group decision-making performance and outcomes with the support of computer-based communication technologies /." Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B1987392X.
Повний текст джерелаWessels, Althia Chavianca. "Social networks utilised by SME's within the tourist destinations of eastern Free State / A.C. Wessels." Thesis, North-West University, 2012. http://hdl.handle.net/10394/9252.
Повний текст джерелаThesis (MBA)--North-West University, Potchefstroom Campus, 2013.
Abbasi, Munir A. "Interoperability of wireless communication technologies in hybrid networks : evaluation of end-to-end interoperability issues and quality of service requirements." Thesis, Brunel University, 2011. http://bura.brunel.ac.uk/handle/2438/5562.
Повний текст джерелаBen, Jaballah Wafa. "Securing wireless sensor and vehicular networks." Thesis, Bordeaux, 2014. http://www.theses.fr/2014BORD0013/document.
Повний текст джерелаWireless sensor and vehicular networks play an important role in critical military and civil applications, and pervade our daily life. However, security concerns constitute a potential stumbling block to the impeding wide deployment of sensor networks and vehicular communications. This dissertation studies communication security for Wireless Sensor Networks (WSNs), and vehicular communication. To this aim, we address four important aspects. The first study addresses broadcast authentication in WSNs. We focus on key disclosure based schemes. We demonstrate that key disclosure delay induces an authentication delay, which could lead to a memory DoS attack. We then propose two broadcastauthentication protocols for WSNs, which overcome the security vulnerability of existingsolutions. The proposed schemes guarantee the efficient management of receiver’s buffer, by employing a staggered authentication mechanism, and a Bloom filter data structure to reduce the communication overhead. We also validate our protocols under the AVISPA model checking tool, and we evaluate them with experiments under TinyOS. Our findings are that these protocols provide source authentication service while respecting the WSN constraints.The second study addresses the storage issue in WSNs, in particular the Delayed AuthenticationCompromise attack (DAC). We first demonstrate that recently proposed schemes, which also address the DAC issue are vulnerable to two kinds of attacks: switch command attack (where an adversary pretends to “switch” two messages over time), and drop command attack (where an adversary just pretends to “hide” a message sent from the broadcaster). As a countermeasure against these attacks, we propose a new solution for broadcast authentication. Our analysis shows that our solution is effective in detecting both switch command and drop command attack, and—at the same time—is more efficient (in terms of both communication and computation) than the state of the art solutions.In the third study, we address key management security in WSNs. We present novel symmetric-key-based authentication schemes which exhibit low computation and communication authentication overhead. Our schemes are built upon the integration of a reputation mechanism, a Bloom filter, and a key binary tree for the distribution and updating of the auxviii thentication keys. Our schemes are lightweight and efficient with respect to communication and energy overhead. The fourth study addresses security in vehicular communications. We focus on fast multi hop broadcast applications. We analyze the security threats of state of the art vehicular based safety applications. We demonstrate that these schemes are vulnerable to the position cheating attack, the replay broadcast message attack, and the interrupting forwarding attack. Then, we propose countermeasures for these threats. We hence propose a complete solution which is both fast and secure in broadcasting safety related messages: Fast and Secure Multi-hop Broadcast Algorithm (FS-MBA). Finally, we confirm the efficiency and feasibility of our proposals using an extensive set of simulations under NS-2 Simulator
Hsueh, Yu-Ting. "Frontiers of optical networking technologies: millimeter-wave radio-over-fiber and 100g transport system for next-generation high-data-rate applications." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/43681.
Повний текст джерелаDare, Julie. "The role of information and communication technologies in managing transition and sustaining women's health during their midlife years." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2009. https://ro.ecu.edu.au/theses/1977.
Повний текст джерелаTeratani, Mehrdad. "3D Image Processing and Communication in Camera Sensor Networks: Free Viewpoint Television Networking." Doctoral thesis, Nagoya University, Nagoya, Japan, 2004. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/319673.
Повний текст джерелаKafaar, Zuhayr. "The combined influence of new information and communication technologies and gender on self-esteem and social support." Thesis, University of the Western Cape, 2005. http://etd.uwc.ac.za/index.php?module=etd&.
Повний текст джерелаThis study discussed the effect of new information and communication technologies use on adolescents. The research also assessed whether gender and frequency of use of new information and communication technologies would interact to influence self-esteem and social support from family and friends.
Stepura, I. S., and M. A. Sablina. "The Experience of Using Social Networks to Attract Students to Scientific Research." Thesis, Sumy State University, 2016. http://essuir.sumdu.edu.ua/handle/123456789/47043.
Повний текст джерелаZaouche, Lotfi. "Sécurité et fiabilité des communications dans les réseaux d’essaims." Thesis, Compiègne, 2017. http://www.theses.fr/2017COMP2339/document.
Повний текст джерелаThe emergence of small and inexpensive Unmanned Aerial Vehicles (UAVs) promotes their use in several applications. UAVs are usually equipped with different sensors and have the ability to communicate via wireless connections. Their capability to fly freely in the space offers new opportunities to monitoring and tracking applications. A Flying Ad hoc Network (FANET) is composed of a fleet of autonomous UAVs and is used for monitoring applications in hostile environments, surveillance or site inspection. FANETs could also be used for filming special events such as bike races or soccer matches, so, the connections must guarantee a minimum of quality of service. In FANETs, saving energy of UAVs that have limited battery is very challenging and protecting the network from malicious attacks is even more difficult. In this thesis, we focus on tracking and filming a moving target using a fleet of UAVs. Since the target is moving, the UAVs have to follow it continuously, and a path to the ground station must be available. In this context, we propose an efficient solution that allows the coordination of the UAVs to maintain an optimal path between the target and the ground station. The proposed solution is time and energy efficient. We also propose a solution based on hierarchical protocols to save more energy in the communication process with the ground station. Another solution that allows energy saving is to force selfish nodes to participate in the network to route received packets towards their destination. Indeed, a selfish node is concerned only about its own welfare, refusing to route packets of other node, causing an extra charge for the rest of nodes in the network. We validate our solutions through simulation campaigns
Munhoz, Fábio Alessandro. "Dinamismos tecno-sociais: sobre redes, co-labor-ação e viruss." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/27/27154/tde-05112010-113323/.
Повний текст джерелаThis research fits into the lines of investigation of the ATOPOS Research Center of Escola de Comunicação e Artes da Universidade de São Paulo [School of Communication and Arts of the University of São Paulo] (ECA/USP) on the theoretical aspects of digital media. Its goal is to analyze the impact of media changes in society, in particular the impact caused by new digital technologies on the forms of social organization. From a perspective that leaves the instrumentalist view of technology media, going to consider them as active elements in the construction of human subjectivity, and consequently, in how humans relate to the world, we analyze how the symbiosis of mandigital networks provides a technosocial experiment based on co-labor-a(c)tion, ie, in joint work aimed at the action. Along that way, we make a historical transformations on the mediasociety relationship, we studied the concept of networking and dialogue on the concept of action / social action. Empirically, we rely on our path through collaborative experiences in digital networks, and conduct research and observations specific to this work.
Carvalho, Gonçalo Nuno Marques Domingos. "Development of an ambient assisted living ecosystem." Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/11224.
Повний текст джерелаThe society that we live in faces today big demographic changes. Nowadays, peo-ple live longer, and it is expected that this trend will proceed. In 2000, there were already 420 million people with more than 65 years old, which correspond to about 7% of the world population. In 2050, it is expected that this number reaches 1500 million which corresponds to about 16% of the world population. Naturally, in these circumstances, the number of disabled people will increase as well. This context brings new challenges to the traditional health care systems in Portugal and in the rest of the world. There is an urgent need to search for new solutions that will allow people to live in the best possible way, in the latest stages of life. In order to fulfill this need, it is necessary to develop systems that allow to extend their life in their favorite environment, improving their safety, autonomy, mobility and welfare. Nowadays, information and communication technologies (ICT) offer new opportunities to provide care and assistance. Ambient Assisted Living (AAL), is such a paradigm, in which technology is used as a way to improve the independ-ence and welfare of aged or disabled people at their homes. This dissertation has the purpose of contributing to providing an answer to this necessity, associated to a development of an ecosystem for Ambient Assisted Living, associated to a business model and the search for the possibility of collabo-rative networks creation, in order to look for efficient and accessible solutions for AAL services provision.
Mursia, Placido. "Multi-antenna methods for scalable beyond-5G access networks." Electronic Thesis or Diss., Sorbonne université, 2021. http://www.theses.fr/2021SORUS532.
Повний текст джерелаThe exponential increase of wireless user equipments (UEs) and network services associated with current 5G deployments poses several unprecedented design challenges that need to be addressed with the advent of future beyond-5G networks and novel signal processing and transmission schemes. In this regard, massive MIMO is a well-established access technology, which allows to serve many tens of UEs using the same time-frequency resources. However, massive MIMO exhibits scalability issues in massive access scenarios where the UE population is composed of a large number of heterogeneous devices. In this thesis, we propose novel scalable multiple antenna methods for performance enhancement in several scenarios of interest. Specifically, we describe the fundamental role played by statistical channel state information (CSI) that can be leveraged for reduction of both complexity and overhead for CSI acquisition, and for multiuser interference suppression. Moreover, we exploit device-to-device communications to overcome the fundamental bottleneck of conventional multicasting. Lastly, in the context of millimiter wave communications, we explore the benefits of the recently proposed reconfigurable intelligent surfaces (RISs). Thanks to their inherently passive structure, RISs allow to control the propagation environment and effectively counteract propagation losses and substantially increase the network performance
Elkashash, Amgad. "Le rôle des technologies de l'information et de la communication (TIC) dans les transformations de la forme urbaine : le cas du Grand Caire." Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUL012.
Повний текст джерелаWith their ability to create, process and transmit information in real time, ICT are playing today a major role in the structuring and development of urban spaces. The present thesis aims to study the relationship between ICT and the transformations of the Greater Cairo’s urban form. To that end, the thesis draws on a multidisciplinary approach that combines quantitative and qualitative methods; it is based on the model of "Urbanism of networks" that divides ICT networks into three levels: infrastructures, information technologies and uses. Many resources are used in this study: reports, specialised books and articles, data collected from the field and various Internet resources including the Big Data. The main results are as follows: at the metropolitan scale, the distribution of ICT networks (infrastructures, information technologies and uses) has drawn an extended area, a continuum, which connects the main urban centers formed during the several historical periods of Greater Cairo. Moreover, ICT, among other factors, have led to the formation in the southern suburb of an eccentric, unplanned economic/residential center, the first of its kind in the millennial history of Greater Cairo. Finally, the results showed an important role of the gated communities, these latter seem to find in ICT the way to better realise their objective: to allow living and working in Greater Cairo without facing the disadvantages of its central space. Overall, ICT, despite their ability to alleviate many spatial constraints, are among the factors that shaped the current urban form of Greater Cairo with all its major problems
Wood, Michael Lee. "Examining the Social Affordances of Communication Technology on Human Relations: A Critique of Networked Individualism from the Perspective of the Ethical Phenomenology of Emmanuel Levinas." BYU ScholarsArchive, 2014. https://scholarsarchive.byu.edu/etd/4145.
Повний текст джерелаBreschi, Karla. "Optimisation multi-objectif des communications dans les réseaux de capteurs hétérogènes." Thesis, Bourgogne Franche-Comté, 2018. http://www.theses.fr/2018UBFCD045/document.
Повний текст джерелаThis thesis studies the problems of bi-objective optimization of communications in heterogeneous wireless sensor networks from the point of view of the transmission range. The first criterion considered is necessarily the energy consumption that needs to be reduced in order to maximize the network lifetime. The second criterion is the data transmission delay, which is essential for real-time applications.To solve the optimality problem of the broadcast, we propose an integer linear program, an approximation algorithm, a meta-heuristic and a heuristic. All these techniques allow us to find or to approximate the optimal solutions for the considered objectives.For the routing case, we propose a cross-layer approach via an integer linear program between the MAC and Data Link layers. Our method calculates the optimal solution, which represents a point of comparison for future heuristics having the same goals
Mainaud, Bastien. "Réseaux de capteurs pour l'assistance aux personnes : conception et développement de mécanismes de fiabilisation." Thesis, Evry, Institut national des télécommunications, 2010. http://www.theses.fr/2010TELE0015/document.
Повний текст джерелаWireless Sensors Networks is a very active research area with a very large scope of possible application. In particular, assistance to person is one of the promising applications. The constraints in this kind of networks are strong and needs of specifics mechanisms. Energy consumption and security are particularly important and are subject of several works. Assistance to person set some robustness constraints and communications reliability. The goal of these works is to define several solutions to answer to these problematic. This work has been split in three different parts. First, a communication platform based on Personal Network techniques was defined. This platform was design, develop and install in a Paris metro station. We made an analytical model of our platform to perform an analysis of its performances. This analysis and the results from the platform installation itself allow us to clearly define the architecture weaknesses and the technologies drawbacks. Second, we developed several solutions to bring reliability to the platform. First, we designed a scheduling algorithm allowing to reduce the bandwidth utilization. This algorithm uses a semantic data analysis to help the data scheduling. Then, we define a solution bringing security to the communications between a sensor node and a remote monitoring terminal. This solution allows to establish a secure end-to-end tunnel between two entities in an heterogeneous network. At last, we were interested to the communications between the platform and the mobile terminal. We focus our work on the reliability aspect of the communications. So, in the last part of this thesis, we suggest a routing protocol using a metric based on the RSSI. Then, we define a cooperative protocol bringing more reliability to the communications
Stoll, Jennifer. "Information sharing in a nonprofit network." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/45767.
Повний текст джерелаRamos, Adriana Anunciaçao. "Écologie, écosophie et réseaux numériques." Thesis, Sorbonne Paris Cité, 2015. http://www.theses.fr/2015USPCB201/document.
Повний текст джерелаIn recent decades, the widespread use of digital communication technologies in daily life gave rise to a new relationship between individual and territory. This relationship, in which different actors are increasingly integrated, surpasses the old dichotomous paradigm characterized by the man versus nature's relationship. Therefore, a new notion of environment, interactive and member of the social space is born as a result of technological representation of nature and the dialogue fostered by digital networks with the territory. The overall objective of this research is to investigate the contemporary ecological imaginary phenomenon from the perspective of the contribution of new digital communication technologies to the forms of representation of nature and interaction with the territory. To this end, the ways and means of interaction between individuals, digital communication technologies and territory will be studied, considering examples of practical use of digital technologies already consolidated. From a participatory study on digital networks, as well as case studies, we intend to further study on the contribution of digital networks as an open informative territory to changes in relation to contemporary sociability and contemporary ecological imaginary
Sheriff, Ray E. "The 2010 Electronics and Telecommunications Research Seminar Series: 9th Workshop Proceedings." University of Bradford, 2010. http://hdl.handle.net/10454/4355.
Повний текст джерелаThis is the ninth workshop to be organised under the postgraduate programmes in electrical and electronic engineering (EEE). The workshop concludes the Research Seminar Series, which has provided a platform for disseminating the latest research activities in related technologies through its weekly seminars. The EEE courses cover a broad range of technologies and this is reflected in the variety of topics presented during the workshop. In total, forty-four papers have been selected for the proceedings, which have been divided into eight sections. The workshop aims to be as close to a `real¿ event as possible. Hence, authors have responded to a Call for Papers with an abstract, prior to the submission of the final paper. This has been a novel experience for many, if not all of the contributors. As usual, authors have taken up the challenge with enthusiasm, resulting in a collection of papers that reflects today¿s research challenges.
School of Engineering, Design and Technology
Rörsch, Jonatan, and Mikael Johansson. "Social Networks : Creating Organizational Benefits out of an Online Conversation." Thesis, Uppsala universitet, Industriell teknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-207086.
Повний текст джерелаFerrand, Paul. "Communications coopératives dans les réseaux autour du corps humain." Phd thesis, INSA de Lyon, 2013. http://tel.archives-ouvertes.fr/tel-00941101.
Повний текст джерелаLima, Junior Josias Barbosa de. "An Energy-aware multipath routing extension for heterogeneous Ad hoc networks." Universidade Federal de Pernambuco, 2013. https://repositorio.ufpe.br/handle/123456789/12385.
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Recent years have witnessed the emergence of new communication techniques in Computer Science that use both wireless technologies and self-organizing features. Their combination eliminates the need for using pre-defined wired structures and prior configurations. In this work, we develop a simulated version, using the network simulator 3 (ns-3), of the Heterogeneous Technologies Routing (HTR) framework that is suitable for interconnecting devices in a heterogeneous ad hoc network, extending its supported heterogeneous technologies with the addition of WiMAX and LTE devices, proposes an extension to enable multipath routing over this framework and investigates the impact of tuning routing parameters on convergence interval and energy consumption. Although a large number of works exist that investigate the tuning of routing parameter settings, to the best of our knowledge, none of them investigate the impact of these on protocol convergence and energy consumption. Multipath HTR routing, the extension we propose, offers several benefits such as load balancing, fault tolerance, routing loop prevention, energy-conservation, low end-to-end delay, and congestion avoidance, among others. This work performs a comparative analysis of the proposed HTR extension, with the baseline HTR, and the widely used Optimized Link State Routing (OLSR) protocol. Moreover, we investigate the impacts of tuning the HELLO refresh interval and perform a comparative analysis of the tuned HTR with the OLSR protocol. Both evaluations are validated through the simulation of heterogeneous technologies such as WiMAX, 3GPP LTE and Wi-Fi. Results show that the multipath extension effectively improves the data delivery ratio, and reduces the end-to-end delay without major impact on network energy consumption. For the tuned HTR, results show that varying the HELLO refresh interval can improve the convergence of the protocol and reduce the energy consumption.
Recentemente, novas técnicas de comunicação surgiram que usam tecnologia sem fio e são capazes de se autoconfigurar. A combinação desses fatores elimina a necessidade de utilizar estruturas cabeadas e configurações pré-definidas. Neste trabalho, o autor desenvolve uma versão simulada, através do simulador de rede “network Simulator 3” (ns-3), do arcabouço “Heterogeneous Technologies Routing” (HTR), que se propõe à interconectar dispositivos em redes heterogêneas ad hoc, estendendo o seu suporte às tecnologias heterogêneas com a adição de dispositivos WiMAX e LTE, propõe uma extensão para fornecer um roteamento baseado em múltiplos caminhos (“Multipath”) e investiga o impacto de modificar os parâmetros de configuração do roteamento no tempo de convergência da rede e consumo de energia. Apesar de um grande número de obras existentes que investigam o impacto da mudança de parâmetros de configuração do roteamento, no meu conhecimento, nenhum deles investiga o impacto destes no tempo de convergência do protocolo e consumo de energia. O “Multipath HTR”, a extensão proposta, oferece vários benefícios como balanceamento de carga, tolerância a falhas, prevenção de “loops” de roteamento, conservação de energia, baixo atraso fim-a-fim, e evita o congestionamento, entre outros. Este trabalho faz uma análise comparativa da extensão ao HTR proposta, com a base do HTR, e o protocolo amplamente utilizado “Optimized Link State Routing” (OLSR). Além disso, o esse trabalho investiga o impacto de variar o intervalo de envio de mensagens de HELLO e realiza uma análise comparativa do HTR modificado (“Tuned HTR”) com o protocolo OLSR. As duas avaliações são realizadas através de simulação usando tecnologias heterogêneas como WiMAX, 3GPP LTE e Wi-Fi. Resultados mostram que a extensão de múltiplos caminhos proposta melhora a taxa de transmissão de dados, e reduz o atraso fim-a-fim sem maiores impactos no consumo de energia da rede. Para o “Tuned HTR”, resultados mostram que a variação do intervalo de envio de mensagens de HELLO pode melhorar a convergência do protocolo e reduz o consumo de energia.
Notley, Tanya M. "The role of online networks in supporting young people's digital inclusion and the implications for Australian government policies." Thesis, Queensland University of Technology, 2008. https://eprints.qut.edu.au/19097/2/Tanya_Notley_Citation.pdf.
Повний текст джерелаNotley, Tanya M. "The role of online networks in supporting young people's digital inclusion and the implications for Australian government policies." Queensland University of Technology, 2008. http://eprints.qut.edu.au/19097/.
Повний текст джерела