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Bainbridge, Christopher James. "Digital control networks for virtual creatures". Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4812.
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Robot control systems evolved with genetic algorithms traditionally take the form of floating-point neural network models. This thesis proposes that digital control systems, such as quantised neural networks and logical networks, may also be used for the task of robot control. The inspiration for this is the observation that the dynamics of discrete networks may contain cyclic attractors which generate rhythmic behaviour, and that rhythmic behaviour underlies the central pattern generators which drive lowlevel motor activity in the biological world. To investigate this a series of experiments were carried out in a simulated physically realistic 3D world. The performance of evolved controllers was evaluated on two well known control tasks—pole balancing, and locomotion of evolved morphologies. The performance of evolved digital controllers was compared to evolved floating-point neural networks. The results show that the digital implementations are competitive with floating-point designs on both of the benchmark problems. In addition, the first reported evolution from scratch of a biped walker is presented, demonstrating that when all parameters are left open to evolutionary optimisation complex behaviour can result from simple components.
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Igumbor, Osedum Peter. "A proxy approach to protocol interoperability within digital audio networks". Thesis, Rhodes University, 2010. http://hdl.handle.net/10962/d1004852.
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Digital audio networks are becoming the preferred solution for the interconnection of professional audio devices. Prominent amongst their advantages are: reduced noise interference, signal multiplexing, and a reduction in the number of cables connecting networked devices. In the context of professional audio, digital networks have been used to connect devices including: mixers, effects units, preamplifiers, breakout boxes, computers, monitoring controllers, and synthesizers. Such networks are governed by protocols that define the connection management rocedures, and device synchronization processes of devices that conform to the protocols. A wide range of digital audio network control protocols exist, each defining specific hardware requirements of devices that conform to them. Device parameter control is achieved by sending a protocol message that indicates the target parameter, and the action that should be performed on the parameter. Typically, a device will conform to only one protocol. By implication, only devices that conform to a specific protocol can communicate with each other, and only a controller that conforms to the protocol can control such devices. This results in the isolation of devices that conform to disparate protocols, since devices of different protocols cannot communicate with each other. This is currently a challenge in the professional music industry, particularly where digital networks are used for audio device control. This investigation seeks to resolve the issue of interoperability between professional audio devices that conform to different digital audio network protocols. This thesis proposes the use of a proxy that allows for the translation of protocol messages, as a solution to the interoperability problem. The proxy abstracts devices of one protocol in terms of another, hence allowing all the networked devices to appear as conforming to the same protocol. The proxy receives messages on behalf of the abstracted device, and then fulfills them in accordance with the protocol that the abstracted device conforms to. Any number of protocol devices can be abstracted within such a proxy. This has the added advantage of allowing a common controller to control devices that conform to the different protocols.
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Sanyamahwe, Tendai. "Digital forensic model for computer networks". Thesis, University of Fort Hare, 2011. http://hdl.handle.net/10353/d1000968.
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The Internet has become important since information is now stored in digital form and is transported both within and between organisations in large amounts through computer networks. Nevertheless, there are those individuals or groups of people who utilise the Internet to harm other businesses because they can remain relatively anonymous. To prosecute such criminals, forensic practitioners have to follow a well-defined procedure to convict responsible cyber-criminals in a court of law. Log files provide significant digital evidence in computer networks when tracing cyber-criminals. Network log mining is an evolution of typical digital forensics utilising evidence from network devices such as firewalls, switches and routers. Network log mining is a process supported by presiding South African laws such as the Computer Evidence Act, 57 of 1983; the Electronic Communications and Transactions (ECT) Act, 25 of 2002; and the Electronic Communications Act, 36 of 2005. Nevertheless, international laws and regulations supporting network log mining include the Sarbanes-Oxley Act; the Foreign Corrupt Practices Act (FCPA) and the Bribery Act of the USA. A digital forensic model for computer networks focusing on network log mining has been developed based on the literature reviewed and critical thought. The development of the model followed the Design Science methodology. However, this research project argues that there are some important aspects which are not fully addressed by South African presiding legislation supporting digital forensic investigations. With that in mind, this research project proposes some Forensic Investigation Precautions. These precautions were developed as part of the proposed model. The Diffusion of Innovations (DOI) Theory is the framework underpinning the development of the model and how it can be assimilated into the community. The model was sent to IT experts for validation and this provided the qualitative element and the primary data of this research project. From these experts, this study found out that the proposed model is very unique, very comprehensive and has added new knowledge into the field of Information Technology. Also, a paper was written out of this research project.
4
Abbadi, Imad Mahmoud Aref. "Digital Rights Management for Personal Networks". Thesis, Royal Holloway, University of London, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487274.
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The thesis is concerned with Digital Rights Management (DRM), and in particular with DRM for networks of devices owned by a single individual. This thesis focuses on the problem of preventing illegal copying of digital assets without jeopardising the right of legitimate licence holders to transfer content between their own devices, which collectively make up what we refer to as an authorised domain. An ideal list of DRM requirements is specified, which takes into account the points of view of users, content providers and copyright law. An approach is then developed for assessing DRM systems based on the defined DRM requirements; the most widely discussed DRM schemes are then analysed and assessed, where the main focus is on schemes which address the concept of an authorised domain. Based on this analysis we isolate the issues underlying the content piracy problem, and then provide a generic framework for a DRM system addressing the identified content piracy issues. The defined generic framework has been designed to avoid the weaknesses found in other schemes. The main contributions of this thesis include developing four new approaches that can be used to implement the proposed generic framework for managing an authorised domain. The four novel solutions all involve secure means for creating, managing and using a secure domain, which consists of all devices owned by a single owner. The schemes allow secure content sharing between devices in a domain, and prevent the illegal copying of content to devices outside the domain. In addition, each solution incorporates a method for binding a domain to a single owner, ensuring that only a single consumer owns and manages a domain. This enables binding of content licences to a single owner, thereby limiting illicit content proliferation. In the first solution, domain owners are authenticated using two-factor authentication, which involves 'something the domain owner has', Le. a master control device that controls and manages consumers domains, and binds devices joining a domain to itself, and 'something the domain owner is or knows', i.e. a biometric or password/PIN authentication mechanism that is implemented by the master control device. In the second solution, domain owners are authenticated using their payment cards, building on existing electronic payment systems by ensuring that the name and the date of birth of a domain creator are the same for all devices joining a domain. In addition, this solution helps to protect consumers' privacy; unlike in existing electronic payment systems, payment card details are not exposed to third parties. The third solution involves the use of a domain-specific mobile phone and the mobil~ phone network operator to authenticate a domain owner before devices can join a domain. The fourth solution involves the use of location-based services, ensuring that devices joining a consumer domain are located in physical proximity to the addresses registered for this domain. This restricts domain membership to devices in predefined geographical locations, helping to ensure that a single consumer owns and manages each domain.
5
Gingold, David. "Integrated digital services for cable networks". Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/10650.
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Zammit, Saviour. "Digital video transmission over wireless networks". Thesis, Aston University, 1995. http://publications.aston.ac.uk/8058/.
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The advent of the Integrated Services Digital Network (ISDN) led to the standardisation of the first video codecs for interpersonal video communications, followed closely by the development of standards for the compression, storage and distribution of digital video in the PC environment, mainly targeted at CD-ROM storage. At the same time the second-generation digital wireless networks, and the third-generation networks being developed, have enough bandwidth to support digital video services. The radio propagation medium is a difficult environment in which to deploy low bit error rate, real time services such as video. The video coding standards designed for ISDN and storage applications, were targeted at low bit error rate levels, orders of magnitude lower than the typical bit error rates experienced on wireless networks. This thesis is concerned with the transmission of digital, compressed video over wireless networks. It investigates the behaviour of motion compensated, hybrid interframe DPCM/DCT video coding algorithms, which form the basis of current coding algorithms, in the presence of high bit error rates commonly found on digital wireless networks. A group of video codecs, based on the ITU-T H.261 standard, are developed which are robust to the burst errors experienced on radio channels. The radio link is simulated at low level, to generate typical error files that closely model real world situations, in a Rayleigh fading environment perturbed by co-channel interference, and on frequency selective channels which introduce inter symbol interference. Typical anti-multipath techniques, such as antenna diversity, are deployed to mitigate the effects of the channel. Link layer error control techniques are also investigated.
7
Yu, Ping Tate Stephen R. "Direct online/offline digital signatures schemes". [Denton, Tex.] : University of North Texas, 2008. http://digital.library.unt.edu/permalink/meta-dc-9717.
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Kouhbor, Shahnaz University of Ballarat. "Optimal number and placement of network infrastructure in wireless networks". University of Ballarat, 2007. http://archimedes.ballarat.edu.au:8080/vital/access/HandleResolver/1959.17/12762.
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Wireless Local Area Networks (WLANs) have become a major success in telecommunications during the last few years, due to advantages such as mobility, flexibility, and easier maintenance. A device called an access point (AP) acts as a base station in WLAN for connecting a group of users to the network via radio signal. During the planning of such a network an important problem is to determine the optimal number of these devices and their placement/distribution so that coverage, capacity, and physical security are maximised at minimum cost. In this thesis we are using continuous optimisation techniques to optimise the number of APs and their distribution while cost of deployment is reduced and physical security of the network is enhanced. To find the number and placement of APs, we developed a multi-objective functions model based on path losses and power for free space environments. The two functions in the models are combined by using a balancing parameter. Since it is recognised that some of the objectives can be handled one at a time, in another approach, we followed a step-by-step procedure. We start with a novel optimisation model based on path losses for indoor environments including obstacles. Cost of deployment is saved by finding the minimum number of APs ensuring that the path loss at each test point/receiver is below the given maximum path loss. Next, the physical security of the network is enhanced by placing the APs far from places accessible to unauthorised users to reduce the risk of intrusion into the network. This is achieved in the framework of the model by introducing potential unauthorised users in unauthorised areas for whom coverage is minimised. Due to the presence of obstacles in indoor buildings, the path loss function is discontinuous. Therefore, the objective functions are very complicated and most of the existing optimisation algorithms cannot be applied to solve the problem. We use a global optimisation algorithm that is not used by other researchers to solve the same problem. To validate the accuracy of the optimisation model and performance of the numerical methods, we run tests on several indoor buildings and use wide range of WLAN parameters. The results demonstrate the quality of our model and algorithm. Based on the proposed model and algorithm, we developed a software to assist the network designers in planning wireless LANs.Doctor of Philosophy
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Kouhbor, Shahnaz. "Optimal number and placement of network infrastructure in wireless networks". Thesis, University of Ballarat, 2007. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/65892.
Pełny tekst źródłaStreszczenie:
Wireless Local Area Networks (WLANs) have become a major success in telecommunications during the last few years, due to advantages such as mobility, flexibility, and easier maintenance. A device called an access point (AP) acts as a base station in WLAN for connecting a group of users to the network via radio signal. During the planning of such a network an important problem is to determine the optimal number of these devices and their placement/distribution so that coverage, capacity, and physical security are maximised at minimum cost. In this thesis we are using continuous optimisation techniques to optimise the number of APs and their distribution while cost of deployment is reduced and physical security of the network is enhanced. To find the number and placement of APs, we developed a multi-objective functions model based on path losses and power for free space environments. The two functions in the models are combined by using a balancing parameter. Since it is recognised that some of the objectives can be handled one at a time, in another approach, we followed a step-by-step procedure. We start with a novel optimisation model based on path losses for indoor environments including obstacles. Cost of deployment is saved by finding the minimum number of APs ensuring that the path loss at each test point/receiver is below the given maximum path loss. Next, the physical security of the network is enhanced by placing the APs far from places accessible to unauthorised users to reduce the risk of intrusion into the network. This is achieved in the framework of the model by introducing potential unauthorised users in unauthorised areas for whom coverage is minimised. Due to the presence of obstacles in indoor buildings, the path loss function is discontinuous. Therefore, the objective functions are very complicated and most of the existing optimisation algorithms cannot be applied to solve the problem. We use a global optimisation algorithm that is not used by other researchers to solve the same problem. To validate the accuracy of the optimisation model and performance of the numerical methods, we run tests on several indoor buildings and use wide range of WLAN parameters. The results demonstrate the quality of our model and algorithm. Based on the proposed model and algorithm, we developed a software to assist the network designers in planning wireless LANs.Doctor of Philosophy
10
Kouhbor, Shahnaz. "Optimal number and placement of network infrastructure in wireless networks". University of Ballarat, 2007. http://archimedes.ballarat.edu.au:8080/vital/access/HandleResolver/1959.17/14597.
Pełny tekst źródłaStreszczenie:
Wireless Local Area Networks (WLANs) have become a major success in telecommunications during the last few years, due to advantages such as mobility, flexibility, and easier maintenance. A device called an access point (AP) acts as a base station in WLAN for connecting a group of users to the network via radio signal. During the planning of such a network an important problem is to determine the optimal number of these devices and their placement/distribution so that coverage, capacity, and physical security are maximised at minimum cost. In this thesis we are using continuous optimisation techniques to optimise the number of APs and their distribution while cost of deployment is reduced and physical security of the network is enhanced. To find the number and placement of APs, we developed a multi-objective functions model based on path losses and power for free space environments. The two functions in the models are combined by using a balancing parameter. Since it is recognised that some of the objectives can be handled one at a time, in another approach, we followed a step-by-step procedure. We start with a novel optimisation model based on path losses for indoor environments including obstacles. Cost of deployment is saved by finding the minimum number of APs ensuring that the path loss at each test point/receiver is below the given maximum path loss. Next, the physical security of the network is enhanced by placing the APs far from places accessible to unauthorised users to reduce the risk of intrusion into the network. This is achieved in the framework of the model by introducing potential unauthorised users in unauthorised areas for whom coverage is minimised. Due to the presence of obstacles in indoor buildings, the path loss function is discontinuous. Therefore, the objective functions are very complicated and most of the existing optimisation algorithms cannot be applied to solve the problem. We use a global optimisation algorithm that is not used by other researchers to solve the same problem. To validate the accuracy of the optimisation model and performance of the numerical methods, we run tests on several indoor buildings and use wide range of WLAN parameters. The results demonstrate the quality of our model and algorithm. Based on the proposed model and algorithm, we developed a software to assist the network designers in planning wireless LANs.Doctor of Philosophy
11
Neale, Jason. "Remote news reports over digital cellular networks". Thesis, University of Essex, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284606.
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Bews, R. "Digital crossover networks for active loudspeaker systems". Thesis, University of Essex, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383428.
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Ko, Yiu Fai. "Digital cellular mobile radio links and networks". Thesis, University of Southampton, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.280911.
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Goh, Cheh-Ngee. "Random multiple access in digital communication networks". Thesis, Imperial College London, 1988. http://hdl.handle.net/10044/1/47079.
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Lavery, D. J. P. "Digital coherent receivers for passive optical networks". Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1408825/.
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The work presented herein explores the use of digital coherent receivers in loss limited transmission with a view to implementation in a 100 km long-reach passive optical network (LR-PON) with a net data rate of 10 Gbit/s per optical network unit. Optical power receiver sensitivity limits are investigated for C-band coherent receivers. Coherent-enabled advanced (amplitude, phase, and polarisation) modulation schemes are characterised in terms of electronic and optical bandwidth requirements and power efficiency to determine the optimum modulation format for a high capacity LRPON. Including the net coding gain achievable with forward error correction, the high power efficiency of polarisation switched (PS) quadrature phase shift keying (QPSK) enables an experimental demonstration of 4 photons/bit receiver sensitivity, while polarisation division multiplexed (PDM) QPSK enables transmission with 5 photons/bit sensitivity; a 0.5 dB power penalty. Nevertheless, PDM-QPSK is identified as the optimum modulation format for coherent LR-PON, due to its 1.25 dB bandwidth efficiency advantage over PS-QPSK. A coherent access network architecture is developed using 10 Gbit/s PDM-QPSK channels in a wavelength division multiplexed configuration. Multiple access is achieved by using the frequency selectivity of the coherent receiver to provide gain to the channel of interest. Combined with high receiver sensitivity, this demonstrates the feasibility of colourless network operation supporting 1024 channels. In bidirectional transmission, crosstalk from backscattering of optical power is mitigated using the receiver frequency selectivity and by using pulse shaping to restrict the optical channel bandwidth. A reflection-to-signal power ratio of 18.5 dB is tolerated without penalty. Practical realisation is addressed by exploring low complexity, multiplier-free digital signal processing (DSP) algorithms for adaptive channel equalisation; algorithms are identified that can be used without penalty. Finally, to address issues of integration, tunable local oscillator lasers, suitable for monolithic integration, are investigated. The receiver DSP is modified to overcome the additional intensity noise from these lasers. In this scenario, the reduced receiver sensitivity would still enable an LR-PON with 128 channels.
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Sirousi, Sorena. "Distributed Digital Beamforming Techniques in Satellite Networks". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
Znajdź pełny tekst źródłaStreszczenie:
In recent years, satellite communication systems, in particular LEO constellations, have been subject of increased attention in the new space race; this is substantiated by the numerous industrial endeavors aiming at providing high-speed broadband access anywhere at anytime, E.G., SpaceX Starlink. In 5G systems, there has been an increased focus to integrate a non-terrestrial component into the broader wireless communication infrastructure. It is expected that this trend will continue in the future. Satellites can provide coverage in areas where a terrestrial infrastructure is congested or unavailable; however, their energy resources are limited and due to the sidelobes in the multiple beam coverage, co-channel interference arises. Here, beamforming is an effective remedy for both problems.
In this thesis, a distributed beamforming solution is investigated and compared with classic centralized methods. The distributed solution benefits from the fact that beamforming is not performed in a centralized manner in a single satellite, but is done collectively. So, if one satellite malfunctions, others can still provide coverage. Lastly, numerical simulations performed in MATLAB substantiate the advantages of distributed beamforming approach.
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Glass, Abdullatif M. "Digital communication networks incorporating mobile data terminals". Thesis, Aston University, 1989. http://publications.aston.ac.uk/8086/.
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The use of digital communication systems is increasing very rapidly. This is due to lower system implementation cost compared to analogue transmission and at the same time, the ease with which several types of data sources (data, digitised speech and video, etc.) can be mixed. The emergence of packet broadcast techniques as an efficient type of multiplexing, especially with the use of contention random multiple access protocols, has led to a wide-spread application of these distributed access protocols in local area networks (LANs) and a further extension of them to radio and mobile radio communication applications. In this research, a proposal for a modified version of the distributed access contention protocol which uses the packet broadcast switching technique has been achieved. The carrier sense multiple access with collision avoidance (CSMA/CA) is found to be the most appropriate protocol which has the ability to satisfy equally the operational requirements for local area networks as well as for radio and mobile radio applications. The suggested version of the protocol is designed in a way in which all desirable features of its precedents is maintained. However, all the shortcomings are eliminated and additional features have been added to strengthen its ability to work with radio and mobile radio channels. Operational performance evaluation of the protocol has been carried out for the two types of non-persistent and slotted non-persistent, through mathematical and simulation modelling of the protocol. The results obtained from the two modelling procedures validate the accuracy of both methods, which compares favourably with its precedent protocol CSMA/CD (with collision detection). A further extension of the protocol operation has been suggested to operate with multichannel systems. Two multichannel systems based on the CSMA/CA protocol for medium access are therefore proposed. These are; the dynamic multichannel system, which is based on two types of channel selection, the random choice (RC) and the idle choice (IC), and the sequential multichannel system. The latter has been proposed in order to supress the effect of the hidden terminal, which always represents a major problem with the usage of the contention random multiple access protocols with radio and mobile radio channels. Verification of their operation performance evaluation has been carried out using mathematical modelling for the dynamic system. However, simulation modelling has been chosen for the sequential system. Both systems are found to improve system operation and fault tolerance when compared to single channel operation.
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Luo, Junwen. "Digital neural circuits : from ions to networks". Thesis, University of Newcastle upon Tyne, 2015. http://hdl.handle.net/10443/2820.
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The biological neural computational mechanism is always fascinating to human beings since it shows several state-of-the-art characteristics: strong fault tolerance, high power efficiency and self-learning capability. These behaviours lead the developing trend of designing the next-generation digital computation platform. Thus investigating and understanding how the neurons talk with each other is the key to replicating these calculation features. In this work I emphasize using tailor-designed digital circuits for exactly implementing bio-realistic neural network behaviours, which can be considered a novel approach to cognitive neural computation. The first advance is that biological real-time computing performances allow the presented circuits to be readily adapted for real-time closed-loop in vitro or in vivo experiments, and the second one is a transistor-based circuit that can be directly translated into an impalpable chip for high-level neurologic disorder rehabilitations. In terms of the methodology, first I focus on designing a heterogeneous or multiple-layer-based architecture for reproducing the finest neuron activities both in voltage-and calcium-dependent ion channels. In particular, a digital optoelectronic neuron is developed as a case study. Second, I focus on designing a network-on-chip architecture for implementing a very large-scale neural network (e.g. more than 100,000) with human cognitive functions (e.g. timing control mechanism). Finally, I present a reliable hybrid bio-silicon closed-loop system for central pattern generator prosthetics, which can be considered as a framework for digital neural circuit-based neuro-prosthesis implications. At the end, I present the general digital neural circuit design principles and the long-term social impacts of the presented work.
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Seeley, Nathaniel. "Digital receipts : a system to detect the compromise of digital certificates /". Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1590.pdf.
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Uriarte, Gabriel Jose. "Fast algorithms for digital transmultiplexer design". Thesis, Staffordshire University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.254380.
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Tamvada, Jagannatha Haritash. "Techno Economic Analysis of Interconnected Digital Home Networks". Thesis, Norwegian University of Science and Technology, Department of Telematics, 2008. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9778.
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A home network is a popular method of allowing computers to communicate with each other within a given residential area or a local area network. Homes are the new frontiers of technology in the current global scenario, a digital interconnected home network is a reality and an efficient means to exchange information seamlessly across different homes and across different geographies is the need of the hour. The interconnection of different homes is possible with the existing ADSL subscriptions but would need changes in the existing gateway structures, which could be challenging for the less techno-savvy. In an effort to make life easier for the end user and help making the interconnection between various home networks seamless, a small device called I-Box is introduced through this project, which is essentially a small UPnP device with rich features and functionalities. This thesis gives an overview of the I-Box technology and with the help of various popular theoretical frameworks and concepts, investigates available Marketing channels and suggests a suitable deployment strategy for the I-Box by making a comparative study of the various possible scenarios and thereby identifying the most suitable model for its deployment.
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Zenteno, Efrain. "Digital Compensation Techniques for Transmitters inWireless Communications Networks". Doctoral thesis, KTH, Signalbehandling, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-167971.
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Since they appeared, wireless technologies have deeply transformed our society. Today, wireless internet access and other wireless applications demandincreasingly more traffic. However, the continuous traffic increase can be unbearableand requires rethinking and redesigning the wireless technologies inmany different aspects. Aiming to respond to the increasing needs of wirelesstraffic, we are witnessing a rapidly evolving wireless technology scenario.This thesis addresses various aspects of the transmitters used in wireless communications.Transmitters present several hardware (HW) impairments thatcreate distortions, polluting the radio spectrum and decreasing the achievabletraffic in the network. Digital platforms are now flexible, robust and cheapenough to enable compensation of HW impairments at the digital base-bandsignal. This has been coined as ’dirty radio’. Dirty radio is expected in future transmitters where HW impairments may arise to reduce transmitter cost or to enhance power efficiency. This thesis covers the software (SW) compensation schemes of dirty radio developed for wireless transmitters. As describedin the thesis, these schemes can be further enhanced with knowledge of thespecific signal transmission or scenarios, e.g., developing cognitive digital compensationschemes. This can be valuable in today’s rapidly evolving scenarioswhere multiple signals may co-exist, sharing the resources at the same radiofrequency (RF) front-end. In the first part, this thesis focuses on the instrumentation challenges andHWimpairments encountered at the transmitter. A synthetic instrument (SI)that performs network analysis is designed to suit the instrumentation needs.Furthermore, how to perform nonlinear network analysis using the developedinstrument is discussed. Two transmitter HW impairments are studied: themeasurement noise and the load impedance mismatch at the transmitter, asis their coupling with the state-of-the-art digital compensation techniques.These two studied impairments are inherent to measurement systems and areexpected in future wireless transmitters. In the second part, the thesis surveys the area of behavioral modeling and digital compensation techniques for wireless transmitters. Emphasis is placed on low computational complexity techniques. The low complexity is motivated by a predicted increase in the number of transmitters deployed in the network, from base stations (BS), access points and hand-held devices. A modeling methodology is developed that allows modeling transmitters to achieve both reduced computational complexity and low modeling error. Finally, the thesis discusses the emerging architectures of multi-channel transmittersand describes their digital compensation techniques. It revises the MIMOVolterra series formulation to address the general modeling problem anddrafts possible solutions to tackle its dimensionality. In the framework of multi-channel transmitters, a technique to compensate nonlinear multi-carrier satellite transponders is presented. This technique is cognitive because it uses the frequency link planning and the pulse-shaping filters of the individual carriers. This technique shows enhanced compensation ability at reduced computational complexity compared to the state-of-the-art techniques and enables the efficient operation of satellite transponders.QC 20150526
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Åkesson, Maria. "Digital Innovation in the Value Networks of Newspapers". Doctoral thesis, Högskolan i Halmstad, Halmstad Embedded and Intelligent Systems Research (EIS), 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-14056.
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After decades of digital developments, we are now entering a truly digital era. Digital information and communication technology has become a naturally embedded part ofthe designed environment we live in. Most parts of life are today pervaded by digital products and services. Evidence of such immersion can be noted in, for instance, media consumption. This development is gradually shaping and cultivating a media environment that is ubiquitous. Such ubiquity is manifested in media’s constant presence and thechanges in media consumption in the purview of digital innovation. Indeed, digital innovation is not only a shift in technology. It alters existing value networks and calls forrethinking existing value perceptions. While this disruptive change driven by digitizationcan be found in many industries, this thesis focuses on its impact on value networks in thenewspaper industry.The digitization of newspapers started with the introduction of the internet in the 90´sand soon emerged into new media innovations. While these new media innovations have not replaced existing media, they have been disruptive to newspaper value networks. Recently, the emergence of yet another digital innovation is specifically interesting whenstudying changes to value networks of the newspaper industry: the e-paper. This innovation (a screen technology very close to print on paper) exhibits inherent valuesthat make future replacement of print on paper a possibility. It is therefore regarded as avery promising technology in the newspaper industry. This thesis can be positioned at the intersection of the friction between forces to embarkon a new media trajectory and forces to hang on to the established structures andcontrol. The research question addressed in this thesis is: How are value networks of newspapers influenced by digital innovation? Addressing the research question, a multimethod approach was adopted to gain a broad understanding of how digital innovationinfluences value networks of newspapers. Drawing on digital innovation literature, the thesis presents a theoretical perspective with which to understand how digital innovation influences value networks. This perspective is instantiated as a model of value network configuration. The model emphasizes the multi-layered, dynamic, dialectic, and diametrical character of value networks in digital innovation. The model is offered as abasis and analytical tool to further explore value networks in digital innovation. This tool is useful for newspaper stakeholders when entering the digital era.
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Jha, Sanjay Kumar. "Artificial neural networks for digital signal processing applications". Thesis, University of Strathclyde, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284097.
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Townsend, Anthony M. (Anthony Michael) 1973. "Wired / unwired : the urban geography of digital networks". Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/30041.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2003.Includes bibliographical references.
This dissertation examines the development of digital network infrastructure in the world's great cities at the turn of the 20th century. Drawing upon the concept of cities as information systems and techniques of communications geography, it analyzes how the physical components of digital networks were deployed in major urban areas during the 1990s. It finds that historical processes and pre-existing differences between places shaped the evolution of this infrastructure at multiple spatial scales; global, metropolitan, and neighborhood. As a result, rather than bringing about the "death of distance", digital network infrastructure actually reinforced many of the pre-existing differences between connected and disconnected places. With the telecom bust of 2000-2002, these differences were likely to persist for a decade or more. Yet just as the development of wired digital network infrastructure slowed, wireless technologies emerged as a more flexible, intuitive, and efficient form of connecting users to networks in everyday urban settings. As a result, an untethered model for digital networks emerged which combining the capacity and security of wired networks over long distances with the flexibility and mobility of wireless networks over short distances. This new hybrid infrastructure provided the technology needed to begin widespread experimentation with the creation of digitally mediated spaces, such as New York City's Bryant Park Wireless Network.
by Anthony M. Townsend.
Ph.D.
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Finchelstein, Daniel Frederic. "Low-power digital processor for wireless sensor networks". Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/34109.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.Includes bibliographical references (p. 69-72).
In order to make sensor networks cost-effective and practical, the electronic components of a wireless sensor node need to run for months to years on the same battery. This thesis explores the design of a low-power digital processor for these sensor nodes, employing techniques such as hardwired algorithms, lowered supply voltages, clock gating and subsystem shutdown. Prototypes were built on both a FPGA and ASIC platform, in order to verify functionality and characterize power consumption. The resulting 0.18[micro]m silicon fabricated in National Semiconductor Corporation's process was operational for supply voltages ranging from 0.5V to 1.8V. At the lowest operating voltage of 0.5V and a frequency of 100KHz, the chip performs 8 full-accuracy FFT computations per second and draws 1.2nJ of total energy per cycle. Although this energy/cycle metric does not surpass existing low-energy processors demonstrated in literature or commercial products, several low-power techniques are suggested that could drastically improve the energy metrics of a future implementation.
by Daniel Frederic Finchelstein.
S.M.
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Ang, Chu Suan. "Continuous media in fast networks". Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239753.
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Sreenan, Cormac John. "Synchronisation services for digital continuous media". Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260690.
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Mouton, Francois. "Digital forensic readiness for wireless sensor network environments". Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/24955.
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The new and upcoming field of wireless sensor networking is unfortunately still lacking in terms of both digital forensics and security. All communications between different nodes (also known as motes) are sent out in a broadcast fashion. These broadcasts make it quite difficult to capture data packets forensically and, at the same time, retain their integrity and authenticity. The study presents several attacks that can be executed successfully on a wireless sensor network, after which the dissertation delves more deeply into the flooding attack as it is one of the most difficult attacks to address in wireless sensor networks. Furthermore, a set of factors is presented to take into account while attempting to achieve digital forensic readiness in wireless sensor networks. The set of factors is subsequently discussed critically and a model is proposed for implementing digital forensic readiness in a wireless sensor network. The proposed model is next transformed into a working prototype that is able to provide digital forensic readiness to a wireless sensor network. The main contribution of this research is the digital forensic readiness prototype that can be used to add a digital forensics layer to any existing wireless sensor network. The prototype ensures the integrity and authenticity of each of the data packets captured from the existing wireless sensor network by using the number of motes in the network that have seen a data packet to determine its integrity and authenticity in the network. The prototype also works on different types of wireless sensor networks that are in the frequency range of the network on which the prototype is implemented, and does not require any modifications to be made to the existing wireless sensor network. Flooding attacks pose a major problem in wireless sensor networks due to the broadcasting of communication between motes in wireless sensor networks. The prototype is able to address this problem by using a solution proposed in this dissertation to determine a sudden influx of data packets within a wireless sensor network. The prototype is able to detect flooding attacks while they are occurring and can therefore address the flooding attack immediately. Finally, this dissertation critically discusses the advantages of having such a digital forensic readiness system in place in a wireless sensor network environment. CopyrightDissertation (MSc)--University of Pretoria, 2012.
Computer Science
unrestricted
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Bulot, Jean-Paul. "Echo cancellation via neural networks". Thesis, Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/15407.
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Fei, Yuanyuan. "Compact MIMO terminals with matching networks". Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/3165.
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The development of wireless communications has significantly changed people’s lifestyles in the last century. It can be shown that the use of multiple antennas, so called multiple-input multiple-output (MIMO) at both link ends can offer further improvement of spectral efficiency and link reliability of wireless systems, which has been studied in the past decade. With the maturity of theory, the practice ofMIMO technology has become feasible, though several problems still need to be solved especially at the receive end. The inadequate antenna spacing limited by the small dimension of the receive terminal causes the mutual coupling (MC) effect, which may degrade MIMO system performance. This thesis focuses on the performance improvement of compact MIMO terminals by introducing matching networks between the receive antenna array and the load terminations. The investigation spans from practical implementation to data analysis, and theoretical derivation to system performance optimisation. The contributions of this thesis are threefold. Firstly, three performance metrics signal correlation (SC), received power and capacity are well studied for compact MIMO terminals with matching networks. An overview of the existing methods to examine these metrics is presented. Especially for the received power, one proper approach is found and two methods are compared and unified analytically. The simulation results reveal that adding matching networks into compact MIMO terminals can significantly improve the system performance. However, SC and received power should be well balanced to achieve a good capacity performance. The second contribution describes the experimental measurement of the analytical SC and received power study of the first contribution. A set-up of two quarter-wavelength monopoles and a ground plane with various matching networks are measured and the system design is aided by two simulation tools SEMCAD and FEKO. The measured results agree well with the analytical prediction though discrepancies exist. The implementation confirms that relatively high total receive power and low SC of the compact array can be achieved by choosing proper load impedance in practice. It also indicates that the load impedance to optimise the received power is different from the one for MIMO capacity maximisation. Finally, inspired by the last finding of the second contribution, the optimal single-port matching (SPM) impedance for capacity maximisation in a two by two compact MIMO system is derived using an upper bound of the ergodic capacity for simplicity. A complete framework for MIMO systems with compact arrays at both link ends is deduced using Z-parameters for the analysis. A closed-form result for the optimal SPMimpedance in high signal-to-noise ratio (SNR) regime is given and proved to be the input impedance of the receive antennas. The optimal SPMnetworks outperform other matching networks for small antenna spacings with any SNR. Moreover, the system performance sensitivity of a two by two MIMO system with coupled half-wavelength dipoles and SPMnetworks is evaluated versus antenna spacing and dipole length. It shows that MIMO capacity is not sensitive to the optimal impedance mismatch with fixed antenna spacing and dipole lengths. However, the MIMO system is relatively sensitive to antenna structure mismatch with a precise optimal matching network. Overall, the optimal single-port match is a feasible technique to improve the performance of the compact MIMO systems.
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Laouar, El Hadi. "Multiprocessor architectures for local area networks". Thesis, University of Salford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.258250.
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Christoffersen, Daniel Arthur 1964. "Internetworking the defense data network with an integrated services digital network". Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276716.
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The motivation behind this thesis is to develop a procedure for internetworking the Defense Data Network (DDN) with an Integrated Services Digital Network (ISDN). To accomplish this internetworking problem an integrated gateway must be designed to compensate for incompatibilities between the two networks. This thesis approaches this problem by giving a description of the two networks, DDN and ISDN, and also presenting a general approach to gateway design. This information is then combined into a detailed procedure for implementing a gateway to internetwork the DDN and ISDN. This is followed by a discussion of the practical aspects of the DDN/ISDN internetworking problem.
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Reti, Tommo. "Digital Content Networks : The Past, the Present and Decentralizing". Doctoral thesis, KTH, Medieteknik och grafisk produktion, Media, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-33447.
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This thesis presents a solution-oriented analysis of current issues in digital content distribution management and content networks. The findings support the view that the recent development in the area has created a few congestion points, both in content distribution and content business, that gather increasing technical, social, financial, and political influence in the world. As pointed out in the work, this is against the ideas of information democracy, network neutrality, and the original visions of the Internet and the World Wide Web. Furthermore, leading content companies are answering to the demands of the exponential content and traffic growth by continuously adding rather similar technological solutions, which increases the environmental problems, i.e., energy consumption and e-Waste, at the rate of this growth. The research time period of this dissertation matches with the emergence and rise of P2P file sharing networks that have introduced a new challenging way of distributing content. In this thesis, they are presented as the main comparison points and controversy to the centralized client-server architecture that dominates the content business. The essential question of this work is simply: How to build a better content network? To understand the meaning of "better" in this context and to state what is a better digital content network, it is necessary to understand existing solutions and their shortcomings. The thesis contributes an analytical framework of concepts and principles for the development of future content networks. How do we change the threat of P2P file sharing into an opportunity for professional content publishers? Actually, all the listed objectives in this work – under performance, privacy, network neutrality, e-commerce, and green computing – are societal in nature. Thus, the objective of this dissertation is to improve societal issues through understanding information technology and its closely related context. Through active participation in the file sharing scene, this work presents the development of content networks from computer networks capable of messaging between machines and systems to user networks where people share digital content. Easy copying to friends with rapidly changing user behavior have created a content platform where culture is evolving at an accelerated speed. Drawing from ten research projects and a score of technical prototypes, this thesis concludes that the P2P content sharing applications with their modern protocols effectively create a more advanced network as overlay than the underlying Internet can offer. The operators, who are excited about Internet technology for their networks, are actually limiting their possibilities right from the beginning. It is essential to distinguish between the development of the Internet and the development of large-scale content distribution network.Denna avhandling presenterar en lösningsorienterad analys av aktuella frågor avseende det digitala nätverket och distributionshantering av digitalt innehåll. Resultaten talar för att den senaste utvecklingen inom området har skapat en del flaskhalsar både vid distribution av innehåll och den digitala medieindustrin, som samlar ökat tekniskt, socialt, ekonomiskt och politiskt inflytande i världen. Som påpekas i arbetet är detta emot idéerna om informationsdemokrati, nätverksneutralitet och de ursprungliga visionerna av Internet och World Wide Web. Vidare svarar ledande digitala företag mot kraven från det exponentiella innehållet och ökande trafik genom att bidra med tämligen likartade tekniska lösningar vilka ökar miljöproblemen, det vill säga energiförbrukning och e-avfall, i takt med denna tillväxt. Forskningens tidsperiod för denna avhandling matchar med uppkomst och ökad användning av P2P-fildelningsnätverk vilket har introducerat ett nytt utmanande sätt att distribuera innehåll. I denna avhandling presenteras de som de viktigaste jämförelsepunkterna och kontroverserna till den centraliserade klient/server-arkitekturen som dominerar innehållet inom den digitala mediemarknaden. Den mest väsentliga frågan i detta arbete är helt enkelt; Hur bygger man ett bättre nätverk för digitalt innehåll? För att förstå betydelsen av "bättre" i detta sammanhang och ange vad som är ett bättre digitalt nätverk är det nödvändigt att förstå existerande lösningar och deras brister. Avhandlingen bidrar med en analytisk ram av begrepp och principer för utvecklingen av ett framtida digitalt nätverk. Hur ändrar vi P2P-fildelning från att vara ett hot till att vara en möjlighet för professionella digitala utgivare? Faktiskt är alla uppställda mål i detta arbete - under prestanda, integritet, nätneutralitet, e-avfall och gröna datorer - samhälleliga av naturen. Således är syftet med denna avhandling att förbättra samhällsfrågor genom förståelse för informationsteknik och dess nära relaterade sammanhang. Genom ett aktivt deltagande i fildelningsscenen presenterar detta arbete utvecklingen av digitalt nätverk från datornätverk kapabla att sända meddelanden mellan maskiner och system till användarnätverk där människor delar digitalt innehåll. Okomplicerad kopiering till vänner med ett snabbt föränderligt användarbeteende har skapat en plattform med ett innehåll där kulturen utvecklas med en accelererande hastighet. Tio forskningsprojekt och en värdering av tekniska prototyper ger slutsatsen att P2P-fildelningsapplikationer med sina moderna kommunikationsprotokoll effektivt skapar ett mer avancerat överliggande nätverk än vad Internet kan erbjuda. Operatörerna, som är entusiastiska över Internet-teknik för sina nätverk, begränsar faktiskt sina möjligheter redan från början. Det är viktigt att skilja mellan utvecklingen av Internet och utvecklingen av det storskaliga distributionsnätverket.
QC 20110519
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Löytynoja, M. (Mikko). "Digital rights management of audio distribution in mobile networks". Doctoral thesis, University of Oulu, 2008. http://urn.fi/urn:isbn:9789514289378.
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Abstract
Nowadays, content is increasingly in digital form and distributed in the Internet. The ease of making perfect copies of the digital content has created a need to develop a means to protect it. Digital rights management (DRM) relates to systems designed to protect the intellectual property rights of the digital content. The DRM systems try to enable a secure distribution of digital content to the users and to prevent the unauthorized copying, usage, and distribution of the content. This is usually done in practice using encryption and digital watermarking techniques.
This thesis concentrates on the problem of protecting and distributing multimedia content securely in mobile environment. The research objectives are: (1) to design an overall DRM architecture which allows an easy content distribution to the user in mobile environment; (2) to develop protection methods that can be used in mobile devices with limited computational capabilities to prevent unauthorized usage of the audio content; (3) to create methods for managing and enforcing the user’s rights and restrictions to the content usage; (4) to study a method for providing the users with an easy access to new digital content and services. The research is carried out by first developing an overall DRM platform to mobile environment. The experimental prototype of the platform is implemented on server side to PC environment and the client runs on a mobile phone. The platform is used to test the functionality and complexity of the content protection methods developed which are based on digital watermarking and encryption techniques.
The main results of the thesis are: (1) a DRM platform for mobile devices that supports peer-to-peer networking and license negotiation; (2) audio protection methods utilizing digital watermarking and encryption techniques which support content superdistribution and content preview; (3) methods for counting offline how many times content has been played on the user’s terminal using watermarking and hash chains; (4) a method for adding metadata, such as a web link, into audio content, so that it survives digital to analog to digital transformation and recording with a mobile phone.
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Fotopoulou, Aristea. "Remediating politics : feminist and queer formations in digital networks". Thesis, University of Sussex, 2012. http://sro.sussex.ac.uk/id/eprint/39666/.
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This thesis examines feminist and queer actors emerging in highly mediated environments and the forms of political organisation and critical knowledge production they engage in. It indicates that older debates around gender and sexuality are being reformulated in digital networks and identifies alternative understandings which are being developed. The study foregrounds a performative conceptualisation and argues that political realities are produced in dynamic configurations of communication media, discourses and bodies. It suggests that network technologies constitute sources of vulnerability and anxiety for feminists and stresses the significance of registering how embodied subjectivities emerge from these experiences. To achieve its aims and to map activity happening across different spaces and scales, the project attended to context-specific processes of mediation at the intersections of online and offline settings. It employed ethnographic methods, internet visualisation, in-depth interviewing and textual analysis to produce the following key outcomes: it registered changing understandings of the political in relation to new media amongst a network of women's organisations in London; it investigated the centrality of social media and global connections in the shaping of local queer political communities in Brighton; it complicated ideas of control, labour and affect to analyse emerging sexual identities in online spaces like nofauxx.com, and offline postporn events; finally, it traced feminist actors gathering around new reproductive technologies, at the crossing fields of grassroots activism and the academy. Today, women's groups and queer activists increasingly use networked communication for mobilisation and information-sharing. In a climate of widespread scepticism towards both representational politics and traditional media, questions about the role of digital networks in enabling or limiting political engagement are being raised. This thesis aims to contribute to these debates by accounting for the ways in which feminist and queer activists in digital networks reformulate the relationship between communication media and politics.
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Weston, Danny Lee. "Digital black boxes : apprehending fast and dynamic sociotechnical networks". Thesis, University of Greenwich, 2016. http://gala.gre.ac.uk/18107/.
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We live in a world now dominated by complex and fast moving sociotechnical systems. This work considers the difficulties presented in even discussing such systems in an intelligible manner, especially given that many escape the immediate capabilities of human cognition to properly apprehend. Numerous means have in recent history been used to ‘fix’ or ‘stabilise’ the meanings and capabilities of such systems through one form of ‘Black Box’ or other. This work argues that our current conceptual resources are not appropriate to the task and explores ways in which both academics and practitioners can effectively and usefully apprehend such fast moving sociotechnical systems. It draws in particular on the work of Bruno Latour and Paul Thagard, combining their notions of ‘Circulating Reference’ and ‘Computational Coherence’ respectively, to propose more dynamic approaches and methodologies situated in kind of Computationalism that can be adapted to enable complex computing and digital networked events and the dynamic sociotechnical networks that underpin them to be talked about, and thereby known in ways that both express and encompass their dynamism and complexity and without inappropriately and prematurely placing them into ‘Black Boxes’.
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Sementilli, Philip Joseph Jr 1958. "Linear feature delineation in digital imagery using neural networks". Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/278012.
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A goal of many image analysis, image understanding and computer vision problems is the delineation of linear features. This thesis addresses the specific problem of operator guided road delineation in aerial photographs. Our solution to this problem applies the classical pattern recognition paradigm of feature extraction followed by pattern classification. The feature extraction process merges features extracted at different levels of a multi-resolution image pyramid to obtain a dichotomization of image coordinates into classes of road pixels and not road pixels. The road center line is estimated from this road pixel image using a generalized Hamming distance based decision scheme. An artificial neural network (ANN) architecture is developed which implements the generalized Hamming distance classifier. It is shown that the ANN implementation offers significant throughput improvements over sequential implementations. Results of applying the road delineation algorithm to digitized aerial photographs demonstrate delineation accuracy suitable for computer-aided cartography applications.
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Srinivasan, Sabeshan. "Object Tracking in Distributed Video Networks Using Multi-Dimentional Signatures". Fogler Library, University of Maine, 2006. http://www.library.umaine.edu/theses/pdf/SrinivasanSX2006.pdf.
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Contreras, Bellido Christian Andres, Salazar José Miguel Cordova, Montoya Valeria Beatriz Espinoza i Ferrer Rubi Ellen Hernandez. "Proyecto Digital Boost". Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2019. http://hdl.handle.net/10757/651778.
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El presente proyecto es una agencia de Marketing Digital para la red social Facebook, dirigida a ofrecer servicios a empresas Mype en Perú, dedicadas principalmente a la comercialización de productos y/o servicios, que tuvieran presupuestos bajos para invertir en un canal digital. La elección de mercado objetivo se obtuvo mediante una investigación de las necesidades de los actuales empresarios del país. Las empresas, en su mayoría, están bajo el régimen Mype, y se vio reflejado en las entrevistas, ya que el 100% de estos pertenecían a este régimen. Además, se rescataron datos importantes, como el reconocimiento de la importancia del Marketing Digital para los empresarios. Hablaron también sobre la necesidad de contar con servicios de diseñadores gráficos y community managers que trabajaran con una estrategia que brindara resultados, por último, esperaban no tener que gastar presupuestos excesivos, ya que esto significaría realizar fuertes sumas de dinero que no disponían. Se encontró una problemática de no encontrar profesionales encargados de implementar una estrategia digital a un precio accesible.
Para la implementación de este proyecto se realizó un análisis del entorno, empezando por estudios del sector: la competencia, los consumidores, los proveedores del servicio y más factores externos que impactaban directa e indirectamente en las empresas de esta industria. Asimismo, para completar la investigación y viabilidad del negocio, se realizaron planes y presupuestos. Entre estos planes se encuentra el Plan de Operaciones, el Plan de Marketing, el Plan de Responsabilidad Social Empresarial, el Plan Estratégico y, por último, el Plan Financiero. Digital Boost ha demostrado su viabilidad mediante cifras, el primer año se obtendrá una utilidad neta de 8,345.46 soles, el segundo año será de 6,353.70 soles y 83,248.21 soles para el tercer año.This project is a Digital Marketing agency focused on Facebook, aimed to offer services to Mype companies in Peru, mainly dedicated to the commercialization of products and services, companies that can afford low budgets to invest in a digital channel. The choice of the target market was made through an investigation of the needs of current businessmen in the country. The companies, for the most part, are under the Mype regime, and it was reflected in the interviews, since 100% of these belonged to this regime. In addition, important data was rescued, such as the recognition of the importance of Digital Marketing for entrepreneurs. They also talked about the need of having graphic designer services and community managers that would work with a strategy that provides real results, finally, they hoped they would not have to spend excessive budgets, since this means carrying out large sums of money that they cannot afford. There was a problem of not finding professionals responsible for implementing a digital strategy at an affordable price in the market. For the implementation of this project, an analysis of the environment was carried out, starting with studies of the sector: competition, consumers, service providers and more external factors that directly and indirectly impact on companies in this industry. Also, to complete the investigation and viability of the business, plans and budgets were made. These plans included the Operations Plan, the Marketing Plan, the Corporate Social Responsibility Plan, the Strategic Plan and, finally, the Financial Plan. Digital Boost has detected its viability through numbers, the first year the project earns a net profit of 8,345.46 soles, the second year will be 6,353.70 soles and 83,248.21 soles for the third year.
Trabajo de investigación
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Chigwamba, Nyasha. "An investigation of parameter relationships in a high-speed digital multimedia environment". Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1021153.
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With the rapid adoption of multimedia network technologies, a number of companies and standards bodies are introducing technologies that enhance user experience in networked multimedia environments. These technologies focus on device discovery, connection management, control, and monitoring. This study focused on control and monitoring. Multimedia networks make it possible for devices that are part of the same network to reside in different physical locations. These devices contain parameters that are used to control particular features, such as speaker volume, bass, amplifier gain, and video resolution. It is often necessary for changes in one parameter to affect other parameters, such as a synchronised change between volume and bass parameters, or collective control of multiple parameters. Thus, relationships are required between the parameters. In addition, some devices contain parameters, such as voltage, temperature, and audio level, that require constant monitoring to enable corrective action when thresholds are exceeded. Therefore, a mechanism for monitoring networked devices is required. This thesis proposes relationships that are essential for the proper functioning of a multimedia network and that should, therefore, be incorporated in standard form into a protocol, such that all devices can depend on them. Implementation mechanisms for these relationships were created. Parameter grouping and monitoring capabilities within mixing console implementations and existing control protocols were reviewed. A number of requirements for parameter grouping and monitoring were derived from this review. These requirements include a formal classification of relationship types, the ability to create relationships between parameters with different underlying value units, the ability to create relationships between parameters residing on different devices on a network, and the use of an event-driven mechanism for parameter monitoring. These requirements were the criteria used to govern the implementation mechanisms that were created as part of this study. Parameter grouping and monitoring mechanisms were implemented for the XFN protocol. The mechanisms implemented fulfil the requirements derived from the review of capabilities of mixing consoles and existing control protocols. The formal classification of relationship types was implemented within XFN parameters using lists that keep track of the relationships between each XFN parameter and other XFN parameters that reside on the same device or on other devices on the network. A common value unit, known as the global unit, was defined for use as the value format within value update messages between XFN parameters that have relationships. Mapping tables were used to translate the global unit values to application-specific (universal) units, such as decibels (dB). A mechanism for bulk parameter retrieval within the XFN protocol was augmented to produce an event-driven mechanism for parameter monitoring. These implementation mechanisms were applied to an XFN-protocol-compliant graphical control application to demonstrate their usage within an end user context. At the time of this study, the XFN protocol was undergoing standardisation within the Audio Engineering Society. The AES-64 standard has now been approved. Most of the implementation mechanisms resulting from this study have been incorporated into this standard.
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Hu, Wei Shu. "Community detection and credibility analysis on social networks". Thesis, University of Macau, 2015. http://umaclib3.umac.mo/record=b3335428.
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Adeodato, Paulo Jorge Leitao. "Theoretical investigation of RAM-based neural networks". Thesis, King's College London (University of London), 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266641.
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Kelly, Kristy. "Emergent Arguments: Digital Media and Social Argumentation". Thesis, University of Oregon, 2017. http://hdl.handle.net/1794/22285.
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This dissertation proposes a new framework for understanding how argumentation and rhetorical action unfold in digital space. While studies in the field of rhetorical theory often address new discursive practices in spaces like Twitter and Facebook, they do not always assess the ways that the platforms themselves can influence the forms and conventions of argumentation. Similarly, the field of new media studies has attended to the structural and technical components of digital platforms, but rarely views these details through a rhetorical lens. Thus, this dissertation combines the two disciplines by approaching its thesis from two angles. First, it employs major scholarly and theoretical work from the field of rhetorical studies to determine the ways in which digital rhetorical practices align with or differ from previous ones. Second, it combines new media scholarship with close readings of digital texts, in order to examine how argumentation functions across different media platforms. This interdisciplinary approach provides unique insight into the ways that media platforms and rhetorical practices coevolve.
The dissertation’s central term, “emergent arguments,” marks an epistemological shift away from the idea that an argument resides within a single text or narrative. Instead, arguments emerge from sustained and engaged interactions with digital communities, from explorations of hyperlinked trails of information, from patterns of images, words, and datasets. In digital space, knowledge is constructed communally, meaning that argumentation takes place in collaboration with a community. The project follows closely with the work of Aristotle and Perelman and Olbrechts-Tyteca, where argumentation is an inherently social act driven by cultural context and shared knowledge. The dissertation builds upon this premise by claiming that digital media make this sociality visible, traceable, and more dynamic than previous communicative platforms. It ultimately argues that in digital space, meaning itself is social, intertextual, and multimodal.
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Al-Alawi, Raida. "The functionality, training and topological constraints of digital neural networks". Thesis, Brunel University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278373.
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McGleenon, Patrick. "Modelling the management behaviour of synchronous digital hierarchy transmission networks". Thesis, Queen's University Belfast, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361221.
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Panchyrz, Lina, i Mohan Karumuri. "Challenges with Organizing for Digital Transformation in International Manufacturing Networks". Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-55974.
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Introduction: The topic of digital transformation plays an increasingly important role and is nowadays inevitable for firms to stay competitive. However, the effects of digital transformation are described as scattered and how to organize for digital transformation in the context of international manufacturing networks has not been investigated previously. This study sets out to explore the challenges that companies face when organizing for digital transformation. The following research questions were stated: RQ1: How do IMNs currently organize for digital transformation? RQ2: What challenges are IMNs facing when organizing for digital transformation? Method: A systematic literature review was combined with a multiple case study to reach the research objectives. Four case companies working with digital transformation in their International Manufacturing Networks and participating in the research project KODIT were part of the study. By this kind of study research study, the phenomenon of interest can be both examined and described. Thereby, a comprehensive context allows to solidify existing knowledge and create new knowledge in order to answer the research questions. Frame of References: A literature review was performed to introduce the concept of International Manufacturing Networks and to create an understanding of digital transformation and its related terms. Organizational change, maturity models and success factors, different approaches, roadmaps, and frameworks, were investigated to provide an insight into current ways of organizing for digital transformation. Furthermore, different challenges related to digital transformation were described. Empirical Findings: The empirical findings provide an overview of how the studied case companies work with digital transformation in their manufacturing networks. Each case company has a different understanding of digital transformation and its way of working. Whereby lead factories, cooperation, and collaboration play an important role. At the same time, the case companies face different challenges when working with digital transformation within an International Manufacturing Network. Analysis and Discussion: Organizing for digital transformation includes various aspects such as structural changes, approaches, success factors, maturity models, roadmaps, and frameworks. Whereby, digital transformation can only be successful when applying a holistic perspective. When undergoing the digital transformation journey numerous challenges have to be faced. By analyzing those challenges, it becomes clear that the introduction of a network perspective increases the complexity of digital transformation. Conclusion and Recommendations: By combining existing literature with a case study, it can be shown how companies currently organize for digital transformation and which aspects are important to consider. Furthermore, a comprehensive overview of potential challenges International Manufacturing Networks can face when working with digital transformation is provided. Hence, this thesis provides a means to develop a holistic understanding of organizing for digital transformation in International Manufacturing Networks. A complete case study is required in the future to validate the findings of this thesis.
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De, la Jara Sánchez César. "Ionospheric echoes detection in digital ionograms using convolutional neural networks". Master's thesis, Pontificia Universidad Católica del Perú, 2019. http://hdl.handle.net/20.500.12404/14984.
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An ionogram is a graph that shows the distance
that a vertically transmitted wave, of a given frequency, travels
before returning to the earth. The ionogram is shaped by making
a trace of this distance, which is called virtual height, against the
frequency of the transmitted wave. Along with the echoes of the
ionosphere, ionograms usually contain a large amount of noise
of different nature, that must be removed in order to extract
useful information. In the present work, we propose to use a
convolutional neural network model to improve the quality of
the information obtained from digital ionograms, compared to
that using image processing and machine learning techniques, in
the generation of electronic density profiles. A data set of more
than 900,000 ionograms from 5 ionospheric observation stations
is available to use.Trabajo de investigación
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Hinojosa, Cristelia. "Organizational Information Dissemination Within Collaborative Networks Using Digital Communication Tools". NSUWorks, 2017. http://nsuworks.nova.edu/gscis_etd/996.
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While knowledge is one of an organization’s greatest assets, it remains a challenge to facilitate knowledge transfer between people within an organization. Social influence has been studied in its role of facilitating information diffusion, which is necessary for knowledge transfer to occur. Among this research, tie strength, a quantifiable characteristic of a social network that determines the link between two nodes, has been measured to determine the impact of social influence on knowledge transfer and information dissemination within a social network. Current research that explores the impact of social influence on information diffusion has been conducted within public social networks due to the availability of data that can be gathered from public social online network systems, such as Facebook. With the emergence of collaboration technologies that exist in online social network tools being utilized within organizations, there is an opportunity to digitally collect information regarding information dissemination within a collaborative network. This study captured data from an online social network, specifically a unified communication tool, being used within a collaborative social network at a mid-sized South Central corporation. A content analysis of Lync messages for 1,749 connections was performed to quantitatively measure the influence of tie strength on information dissemination within a collaborative social network. The results demonstrated that tie strength had a significant impact on information dissemination using a collaborative system. Multivariate analysis of variance showed that tie strength had the largest impact on information dissemination using the instant messaging modality of a collaboration system.
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Jalal, Rakib S. "Transmission of image data over digital networks involving mobile terminals". Thesis, Aston University, 1990. http://publications.aston.ac.uk/8084/.
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There is a growing demand for data transmission over digital networks involving mobile terminals. An important class of data required for transmission over mobile terminals is image information such as street maps, floor plans and identikit images. This sort of transmission is of particular interest to the service industries such as the Police force, Fire brigade, medical services and other services. These services cannot be applied directly to mobile terminals because of the limited capacity of the mobile channels and the transmission errors caused by the multipath (Rayleigh) fading. In this research, transmission of line diagram images such as floor plans and street maps, over digital networks involving mobile terminals at transmission rates of 2400 bits/s and 4800 bits/s have been studied. A low bit-rate source encoding technique using geometric codes is found to be suitable to represent line diagram images. In geometric encoding, the amount of data required to represent or store the line diagram images is proportional to the image detail. Thus a simple line diagram image would require a small amount of data. To study the effect of transmission errors due to mobile channels on the transmitted images, error sources (error files), which represent mobile channels under different conditions, have been produced using channel modelling techniques. Satisfactory models of the mobile channel have been obtained when compared to the field test measurements. Subjective performance tests have been carried out to evaluate the quality and usefulness of the received line diagram images under various mobile channel conditions. The effect of mobile transmission errors on the quality of the received images has been determined. To improve the quality of the received images under various mobile channel conditions, forward error correcting codes (FEC) with interleaving and automatic repeat request (ARQ) schemes have been proposed. The performance of the error control codes have been evaluated under various mobile channel conditions. It has been shown that a FEC code with interleaving can be used effectively to improve the quality of the received images under normal and severe mobile channel conditions. Under normal channel conditions, similar results have been obtained when using ARQ schemes. However, under severe mobile channel conditions, the FEC code with interleaving shows better performance.