Dissertations / Theses: 'Virtual access'

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Stantic, Bela. "Access Methods for Temporal Databases." Thesis, Griffith University, 2005. http://hdl.handle.net/10072/365973.

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A Temporal database is one that supports some aspect of time distinct from user defined time. Over the last two decades interest in the field of temporal databases has increased significantly, with contributions from many researchers. However, the lack of efficient access methods is perhaps one of the reasons why commercial RDBMS vendors have been reluctant to adopt the advances in temporal database research. Therefore, an obvious research question is: can we develop more robust and more efficient access methods for temporal databases than the existing ones? This thesis attempts to address this question, and the main contributions of this study are summarised as follows: We investigated different representations of 'now' and how the modelling of current time influences the efficiency of accessing 'now relative' temporal data. A new method, called the 'Point' approach, is proposed. Our approach not only elegantly models the current time but also significantly outperforms the existing methods. We proposed a new index structure, called a Virtual Binary tree (VB-tree), based on spatial representation of interval data and a regular triangular decomposition of this space. Further, we described a sound and complete query algorithm. The performance of the algorithm is then evaluated both asymptotically and experimentally with respect to the state-of-the-art in the field. We claim that the VB-tree requires less space and uses fewer disk accesses than the currently best known structure - the RI-tree. Thesis (PhD Doctorate) Doctor of Philosophy (PhD) School of Information and Communication Technology Full Text

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Hussain, Nasir. "Cooperative communication in relay assisted wireless access networks." Thesis, Queensland University of Technology, 2017. https://eprints.qut.edu.au/103528/1/Nasir_Hussain_Thesis.pdf.

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This research investigates the benefits of user cooperation in wireless communications systems. The dynamics of wireless cooperative communication systems are studied by a comprehensive study of two essential characteristics of cooperation, optimal relay selection criteria and practical channel estimation. A novel relay selection model based on realistic channel estimation is proposed and analysed. Furthermore, the gains are experimentally evaluated using a wireless communication testbed. The outcomes of this research reveal that incorporating cooperative techniques with an adaptive relay selection strategy into existing wireless communication can significantly reduce the required power and the impact of wireless channel impairments.

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Coetzee, Marijke. "WSACT - a model for Web Services Access Control incorporating Trust." Thesis, Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-07102008-075251.

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MacLennan, Alan. "Design of virtual worlds for accessing information : discovery of user preferences." Thesis, Robert Gordon University, 2007. http://hdl.handle.net/10059/320.

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This thesis describes a study carried out with the aim of discovering user preferences as to the design of 3-dimensional virtual worlds for accessing information. No literature was found which dealt with this topic, and it was therefore thought that, rather than ask users to make a selection from arbitrarily-chosen designs, it would be informative to consult the users from the beginning of the design process. To this end, a Grounded Theory methodology was adopted, and users were selected from postgraduate students and staff from Information Management courses at the Robert Gordon University, Aberdeen. Three “rounds” of interviews were conducted. The first round was concerned with finding out what ideas for a world design people would have, the second with testing four worlds derived from the first round, and the third with exploring further ideas that users had, based on their experience of the test worlds. At each stage of the process, emergent theories were constructed, and modified according to subsequent findings. It was established that the factors which influenced this group of users in their preferences for the design of worlds were not structural, as might have been assumed, but instead were related to properties such as familiarity, organisation, assistance, and quality of information and presentation. When the results were examined in the context of developments in the use of virtual environments, it was found that they provide a theoretical underpinning for practices such as the provision of “conventional” library structures in the popular online environment Second Life. This is not a statistical exercise, but it would appear that there are no significant differences based on the criteria of age, gender, or whether a user was staff or student. More thorough studies would be required to determine this absolutely, but for the moment it appears more useful to draw a broad set of conclusions. ii Issues were identified which indicate potentially rewarding areas for further research and design. Specifically, it would be of interest to discover whether the affective responses of these groups are also common to other groups, and to experiment further with worlds designed in the light of the current findings. Further investigation of the small number of cases in which users do not respond to the worlds would also be desirable, to determine whether this response is characteristic of a group of people who will not react positively to any world, or whether these users simply reacted negatively to the examples presented.

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Wilmott, Deirdre. "What is the value of meaning created through social learning in informal virtual communities?" Thesis, Federation University Australia, 2016. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/102998.

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This study asks the question ‘What is the value of meaning created through social learning in informal virtual communities?’. By researching how people learn in two virtual communities of practice, based around forums, it endeavours to explore learning in online environments that are unconnected to workplace or educational institutions. Both communities studied in this project are meeting places for peers who pursue a domain of personal interest, hence neither community defines itself as a learning environment but as a social meeting place for people to share similar pursuits. The rationale of this study was to explore in-depth the plethora of resources that forum-based communities offer researchers of learning outside the academy, in order to understand the intricacies of un-facilitated social learning. A research strategy for this study was developed from Crotty's (1998) platform which defines: research methods; a methodology; a theoretical perspective; and an epistemology. Triangulated research methods of interview, observation, and personal participation form the basis of data collection. Ethnography, which incorporates auto-ethnography, was the chosen methodology, and the study is centred on a constructivist epistemology. This study employs an interpretivist theoretical perspective, relying on the approaches of two theorists to analyse the data. Both communities were explored by developing four specific propositions from an in-depth analysis of the available literature on informal learning, virtual environments and communities, together with the theoretical understandings of Wenger (1998) regarding Communities of Practice, and Candy (1991) relating to autodidactic and constructed learning. Two viewpoints were chosen because whilst there are a number of theoretical perspectives that can be applied to informal learning in a virtual environment, there is no one agreed theory which comprehensively explains the complexities of individual and social learning in virtual communities. Despite recognition of the Internet as a major source of many people’s informal learning, there is still comparatively limited research undertaken on how this happens. This study is intended to assist in the reduction of this gap by examining aspects of learning including: the connection between autonomous learners and virtual communities; the effect of the written format of the communities observed on dispersing meaning; and the impact of the virtuality of the community on the process of learning and creation of meaning. By undertaking an ethnographical examination of the nature of learning in two informal virtual communities based around written asynchronous forums, this study is intended to contribute to understanding the worth of informal learning in virtual communities where learning occurs between peers. This study contributes to knowledge through its exploration of the way learning occurs in un-facilitated environments and the legitimacy of the outcomes of that learning. Through this exploration, it fosters an appreciation of the value of meaning created in these social environments, as well as their role in validation of communal and individual meaning. It is able to do this by circumnavigating the difficulties earlier researchers have had in developing in-depth studies of the topic because it does not rely implicitly on the perspectives of those participating, or limited-time observations. The study concludes that for both communities their virtuality greatly influences the way their practice develops, as well as how this practice shapes the way in which their members learn in informal environments. It also concludes that learning in these environments is a very complex, often sophisticated, and sometimes contradictory process that is governed by many different, and occasionally competing, aims of individuals and communities. This study also resolved that because of the very complexity of this learning, these two communities produce some very deep and meaningful contributions to their respective domains. As individuals connected within these communities in order to explore their interest in their respective domains, the communities became: repositories of ideas and resources; places to engage in negotiating and renegotiating meaning; and places to validate personal meaning through testing against established community understandings and peer views. Thus after extensive ethnographical research on both communities of this study, it is considered that this work advances the knowledge of learning outside the academy by providing evidence that people do learn effectively in informal virtual communities Doctor of Philosophy

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Ghodke, Ninad Hari. "Virtualization techniques to enable transparent access to peripheral devices across networks." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0005684.

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Lin, Chao-Yu. "Investigating the potential of on-line 3D virtual environments to improve access to museums as both an informational and educational resource." Thesis, De Montfort University, 2009. http://hdl.handle.net/2086/2422.

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New digital technological possibilities allow physical museum artefacts to be transferred into a virtual environment using 3D computer models with rich information content for educational purposes. However, although several museum websites have applied relevant educational theories to learning activities in these 3D environments, these alone are not enough to develop 3D museum environments without consideration of virtual visiting styles in the learning context. This research addresses the relationship between visiting styles and the design of 3D museum environments based on pedagogic approaches for learning efficacy. Relevant literature on the nature of web-based museum systems was reviewed. Three stages of primary research (a critical review, observations and interviews) were also conducted in this study. The critical review examined the use of 3D technologies in current museum websites in terms of informational aspects and the learning context. The observation studies identified the relationship between visitor behaviours and associated learning activities within 3D museum environments. The interviews further elicited experts’ views and were used to test the research hypotheses. A theoretical design reference model was developed. Initially based on the Reeves multimedia design model, the model consists of three phases: analysis, design and assessment. A prototype 3D exhibition was created based on the theoretical model and two pedagogic approaches. Evaluation of this showed that the design of the exhibits with rich multimedia formats had the potential for more effective visitor learning. The two pedagogic approaches encouraged the related visiting style(s), leading to a deeper engagement with the content and ultimately improving learning efficiency.

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Colwell, Chetz. "Non-visual access to the World Wide Web : investigations of design guidelines and haptic interfaces." Thesis, University of Hertfordshire, 2001. http://oro.open.ac.uk/40788/.

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This thesis investigates two different approaches to improving access to the Web for visually impaired people: the design of Web content; and the presentation of content. The potential for improving the design of Web content was investigated in an evaluation of the usability of the Web Content Accessibility Guidelines of the Web Accessibility Initiative. Student Web page authors used the Guidelines to adapt Web pages containing various elements (such as images and tables). These pages were collated into a Web site, which was evaluated by visually impaired people. The page authors found it difficult to find the information they required in the Guidelines document, and had difficulties with implementing the advice of the guidelines. The visually impaired people who evaluated the pages found that the extent of the accessibility of the different elements varied depending on the individual’s experience of using the Web, and the software they used. The accessibility of some elements was not improved by the implementation of the guidelines. The potential for improving the presentation of Web content was investigated using a haptic device. The perception of virtual textures and objects by blind and sighted people via this device was examined. It was found that the virtual textures were perceived differently to the real textures examined in the literature, and that the blind people could better discriminate between the textures than the sighted people could. The virtual objects were explored from the inside and from the outside. It was found that objects generally felt larger from the inside than from the outside. This has been termed the ‘Tardis’ effect. The thesis concludes that it is difficult to define what we mean by ‘accessibility’. Without a clear definition it is not possible to judge whether a Web site is ‘truly’ accessible. The difficulties in making Web content fully accessible mean that additional methods are required for presenting the content in different ways. The researcher believes that haptic devices offer one such method, and could be particularly useful in presenting information that is visual in nature, such as information laid out in columns.

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Kemel, Paul. "Virtual streetgames : a mixed methods study exploring the delivery of an online youth physical activity program." Thesis, Federation University of Australia, 2021. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/177158.

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Prior to the COVID-19 pandemic there was already considerable concern relating to the declining physical activity rates of adolescents and young adults seen across the world. The COVID-19 pandemic, along with the various corresponding social distancing and lockdown guidelines, has further exacerbated these concerns. The utilisation of various forms of technology to maintain and encourage a degree of social connectedness during these timeframes sparked a degree of creativity in how our usual ways of interacting could be modified to the unique social-political circumstances. One such example is the youth community physical activity program Latrobe Streetgames, who adapted their program to be delivered across a range of social media platforms. A mixed methods study was conducted to help understand the impact that the adapted online program had on its participants during the COVID-19 pandemic. The results of the study highlight the negative impact that the various COVID-19 lockdowns had on the target population, and while the ability to maintain some degree of social-physical intractability via the modified Latrobe Streetgames delivery was beneficial, it likely did not outweigh the negative impact of the lockdowns itself. Therefore, as the world moves pasts the pandemic, an emphasis needs to be placed on ensuring that youth physical activity is promoted in order to combat the acquired negative health effects relating to physical, mental and social health. Masters by Research

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Kopp, Christian. "Structural analysis of Online Romance Scams by applying the transtheoretical model in conjunction with the theory of personal love stories." Thesis, Federation University Australia, 2016. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/158439.

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The internet has become an important communications platform which people choose for personal interactions. One of the most popular manifestations is the creation and maintenance of social relationships using social and dating websites. Unscrupulous operators have identified its potential for reaching vulnerable people and have started using it as platform for their criminal activity in the form of so-called Online Romance Scams. Quickly, this cybercrime has become very successful and thus an increasing threat in the social networking environment. The Online Romance Scam causes considerable financial and emotional damage to the victims. In this research we introduce a theory which helps to explain the success of this scam. In a similar way to the “The Nigerian Letter”, we propose that the scam techniques appeal to strong emotions, which are clearly involved in Romantic relationships. We also assume that the same success factors of normal relationships contribute to the success of the Romance Scam. Previous research into normal relationships has identified personal “love stories” as an important factor for the development of relationships. We have suggested that these personal love stories will have a key role in fraudulent relationships. The aim of this research is to explore Online Romance Scams as a type of ‘virtual love’ which initially creates happiness for the victim in a virtual romantic relationship, but tragically then causes the victim to be separated from his or her savings. Using narrative research methodology, this research will establish a model of the Romance Scam structure and its variations regarding human romantic attitudes. During the research program, the analysis of publicly available data from the internet were used, and as a consequence of this, appropriate ethical usage of research data is discussed. Findings of this research will contribute to the knowledge of the Online Romance Scam as significant crime, and provide information about the structure and the development of the modus operandi which can be used to identify an online relationship as a scam at an early phase in order to prevent significant harm to the victim. Doctor of Philosophy

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Macfadyen, Alyx. "A methodology for the analysis of interactive narrative environments : a four-factor framework." Thesis, University of Ballarat, 2009. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/66537.

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Stories have been engaging humans for thousands of years, but in interactive narrative environments, the narrative is perceived to diminish as the source of engagement. One reason for this apparent diminution, is that in interactive environments there has been difficulty in understanding the relationship between design of the unfolding story, and the ability of a user within the story to alter the course of events. As yet there are no standard or accepted evaluative methods to understand interaction at a granular level, and to understand how stories and narratives flow across the expanse of technologies and mixed realities that characterise the way people communicate, share knowledge and are entertained. This thesis presents a novel methodology called the Four-Factor Framework, that takes as its premise that there are four fundamental elements in interactive stories and narratives that can be observed. Doctor of Philosophy

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Bergvall, Ricardo. "Secure remote access to a work environment." Thesis, Högskolan i Halmstad, Akademin för informationsteknologi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-45124.

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This project is about how free, open-source tools can create reasonable, secure and flexible remote access solutions for smaller companies with a limited budget. Secure remote access to a working environment is a solution for its time, as last year Covid-19 change the working environment for millions of employers and employees. The importance of secure remote access to a working environment became noticeable as offices closed down and employers started working from home. Still, the need for secure access to the company's infrastructure remains. This is where Virtual Private Networks (VPNs) enter the picture, as it has a broad application scope and is particularly useful for secure remote access. My project was subdivided into three parts: How to implement secure remote access to a working environment within the requirements of the chosen company, which are an inexpensive solution with high-security features. Automate the creation and distribution of all the necessary parts that their employees will need in a VPN structure. Research about the future direction regarding VPN and the importance of cybersecurity to help ensure security preparedness for the company. The chosen solution was OpenVPN and Google authenticator, together with a written bash script. It became a solution that was free, flexible, secure and scalable. But why the need and what about the future? Research shows that a high percentage of small and medium-sized enterprises are vulnerable to cyberattacks. It also shows that these companies have the lowest cybersecurity. "It wouldn't happen to us" is dangerous but, sadly, a typical mindset throughout the S&M companies. It's primarily because of this S&M's are more exposed than larger companies. The future of VPN's has become more important than ever before, and it's something that during Covid-19 has risen in use all over the world, the research and development of VPNs has accelerated. The research objectives of this project are of high interest to many other organizations in the same position, and the presented work has helped answer the question: "Where will we stand in a few years regarding secure remote work, cybersecurity andencrypted networks?"

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Borgqvist, André. "Reliable access to synchronized world state information in peer to peer networks." Thesis, Blekinge Tekniska Högskola, Avdelningen för för interaktion och systemdesign, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-5887.

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Virtual environments where users can interact with each other as well as with the environment are today used in many application areas ranging from military simulations to massive multiplayer online games. But no matter the application area, as soon as the number of users reaches a certain threshold, hosting a virtual environment on a single machine can become problematic. Speed and quality of the network connection will limit the number of concurrently connected users in terms of acceptable visual quality and hardware requirements of the server will be strict. With a single point of failure, system reliability could easily be compromised by means of network or host failure. Distribution of the virtual environment therefore seems a reasonable approach in order to address this problem. Hardware and network requirements would not be so critical and it would increase reliability by having no single point of failure. Unfortunately distribution introduces new problems dealing with synchronization of the world state within the distribution network. A possible solution to these problems with the focus on reliability will be presented in this thesis. The solution uses a peer to peer platform that is able to adapt to changes in the network infrastructure as a base for all communication. To improve synchronization efficiency the network will be dynamically divided into multicast groups based on synchronization needs. The solution will be tested for performance with the network fully functioning and in a number of more of less broken states to determine the reliability. The results from the tests conclude that the system is able to perform with what must be seen as acceptable performance levels even in very problematic network environments. The scalability of the system did also meet the expectations but the results would have benefited from more experimentation with larger user populations. Virtuella världar där användare kan träffas och interagera med både varandra och miljön används idag i inom flera områden så som militära simulatorer och online-spel. Men det spelar ingen roll vad användningsområdet är, när antalet anvädare når en viss gräns blir det problematiskt att hålla den virtuella världen på en maskin. Distribuering kan vara en lösning på detta problem men som i sin tur drar med sig nya problem i form av synkroniseringssvårigheter. En potentiell lösning presenteras i rapporten som använder peer-to-peer-tekniker för att hålla informationen synkroniserad och försöker upprätthålla en hög tillgänlighet under svåra nätverksförhållande. Lösningen har testats och uppvisade låvande resultat inom båda skalbarhet och pålitlighet men skulle behöva fler tester för att ge definitiva resultat.

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Rouse, Matthew David. "Design and evaluation of a remote access hydraulic manipulator for system dynamics and controls education." Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/18943.

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Pereira, Anil L. "Role-based Access Control for the Open Grid Services Architecture – Data Access and Integration (OGSA-DAI)." Wright State University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=wright1176331524.

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Kruger, Rynhardt Pieter. "Virtual world accessibility: a multitool approach." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/95932.

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Thesis (MSc)--Stellenbosch University, 2014. ENGLISH ABSTRACT: Computer-based virtual worlds are increasingly used for activities which previously required physical environments. However, in its mainstream form, such a virtual world provides output on a graphical display and is thus inaccessible to a blind user. To achieve accessibility for blind users, an alternative to graphical output must be used. Audio and text are two output methods that can be considered. However, when using audio, care must be taken not to overload the audio channel. Channel overloading is possible with audio since it is not a selective output medium like the visual channel, that is, the user cannot choose what he/she wants to hear. Text should also be treated as audio, since a blind user consumes textual information as synthesized speech. In this research we discuss one possible solution to the problem of channel overloading, by the use of multiple exploration and navigation tools. These tools should allow the user to shape the information provided as audio output. Specially, we discuss the development of a virtual world client called Perspective, enabling non-visual access to virtual worlds by the use of multiple navigation and exploration tools. Perspective also serves as a framework for tool implementation and evaluation. Finally we give recommendations for improvements to current virtual world building practices and protocols, as to work toward an accessibility standard. AFRIKAANSE OPSOMMING: Rekenaargebaseerde virtuele wêrelde word toenemend gebruik vir aktiwiteite wat voorheen fiesiese omgewings benodig het. Tog verskaf so 'n virtuele wêreld, in sy standaard vorm, afvoer as 'n grafiese beeld en is dus ontoeganklik vir 'n blinde gebruiker. Om toeganklikheid vir blinde gebruikers te bewerkstellig, moet 'n alternatief vir die grafiese beeld gebruik word. Klank en teks is twee alternatiewe wat beskou kan word. Tog moet klank versigtig gebruik word, aangesien die klankkanaal oorlaai kan word. Die klankkanaal kan oorlaai word aangesien dit nie 'n selektiewe kanaal soos die visuele kanaal is nie, met ander woorde, die gebruiker kan nie kies wat hy/sy wil hoor nie. Teks moet ook as klank beskou word, aangesien 'n blinde gebruiker teks in die vorm van gesintetiseerde spraak inneem. Met hierdie navorsing bespreek ons een oplossing vir die probleem van kanaaloorlading, deur die gebruik van verskeie navigasie- en verkenningsgereedskapstukke. Hierdie gereedskapstukke behoort die gebruiker in staat te stel om die inligting wat as klank oorgedra word, te bepaal. Ons bespreek spesi ek die ontwikkeling van 'n virtuele wêreld-kliënt genaamd Perspective, wat nie-visuele toegang tot virtuele wêrelde bewerkstellig deur die gebruik van meervoudige navigasie- en verkenningsgereedskapstukke. Perspective dien ook as 'n raamwerk vir die ontwikkeling en evaluering van gereedskapstukke. Laastens verskaf ons voorstelle vir verbeteringe van die boutegnieke en protokolle van huidige virtuele wêrelde, as eerste stap na 'n toeganklikheidsstandaard vir virtuele wêrelde.

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Blackmon, Ferrol R. "Virtual Dynamic Tunnel: A Target-Agnostic Assistive User Interface Algorithm for Head-Operated Input Devices." Digital Archive @ GSU, 2010. http://digitalarchive.gsu.edu/cs_diss/58.

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Today the effective use of computers (e.g. those with Internet browsers and graphical interfaces) involves the use of some sort of cursor control like what a mouse provides. However, a standard mouse is not always the best option for all users. There are currently many devices available to provide alternative computer access. These devices may be divided into categories: brain-computer interfaces (BCI), mouth-based controls, camera-based controls, and head-tilt controls. There is no single solution as each device and application has to be tailored to each user's unique preferences and abilities. Furthermore, each device category has certain strengths and weaknesses that need to be considered when making an effective match between a user and a device. One problem that remains is that these alternative input devices do not perform as well when compared to standard mouse devices. To help with this, assistive user interface techniques can be employed. While research shows that these techniques help, most require that modifications be made to the user interfaces or that a user's intended target be known beforehand by the host computer. In this research, a novel target-agnostic assistive user interface algorithm intended to improve usage performance for both head-operated and standard mouse devices is designed, implemented (as a mouse device driver and in host computer software) and experimentally evaluated. In addition, a new wireless head-operated input device requiring no special host computer hardware, is designed, built and evaluated. It was found that the Virtual Dynamic Tunnel algorithm improved performance for a standard mouse in straight tunnel trials and that nearly 60% of users would be willing to use the head-tilt mouse as a hands-free option for cursor control.

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Di, Cicco Nicola. "Scalable Algorithms for Cloud Radio Access Network (C-RAN) Optimization." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/23755/.

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In the evolving scenario of 5G networks, resource allocation algorithms for the Cloud Radio Access Network (C-RAN) model have proven to be the key for managing ever increasing Capital Expenditure (CAPEX) and Operating Expenditure (OPEX) for mobile networks while ensuring high Quality of Service (QoS). In Chapter 1 a brief overview of the main elements of the C-RAN and of the methodologies that are employed in this work is provided. In Chapter 2, an exact scalable methodology for a static traffic scenario, based on lexicographic optimization, is proposed for the solution of a multi-objective optimization problem to achieve, among other goals, the minimization of the number of active nodes in the C-RAN while supporting reliability and meeting latency constraints. The optimal solution of the most relevant objectives for networks of several tens of nodes is obtained in few tens of seconds of computational time in the worst case. For the least relevant objective a heuristic is developed, providing near optimal solutions in few seconds of computing time. In Chapter 3, an optimization framework for dynamic C-RAN reconfiguration is developed. The objective is to maintain C-RAN cost optimization, while minimizing the cost of virtual network function migration. Significant savings in terms of migrations (above 82% for primary virtual BBU functions and above 75% for backup virtual BBU functions) can be obtained with respect to a static traffic scenario, with execution time of the optimization algorithm below 20 seconds in the worst cases, making its application feasible for dynamic scenarios. In Chapter 4, an alternative Column Generation model formulation is developed, and the quality of the computed lower bounds is evaluated. Further extensions from this baseline (e.g. Column Generation based heuristics, exact Branch&Price algorithms) are left as future work. In Chapter 5, the main results achieved in this work are summarized, and several possible extensions are proposed.

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Löfgren, Oskar, and Anna Österström. "Lessons learnt from quality improvement in radiological service : Four key factors for sucess." Thesis, Högskolan i Jönköping, The Jönköping Academy for Improvement of Health and Welfare, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-19146.

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BackgroundIn this study, we describe a Quality Improvement (QI) intervention in three radiology departments within the Swedish health care system, with a special focus on access and methodology. AimThe goals for the QI-intervention were to implement best practice for patients with suspected colon cancer, and reduce the Turn Around Time (TAT).The aim of the study was to identify relevant factors for successful QI in order to further develop the organisation to create a system of continuous QI (CQI) for the radiological service. MethodsInitially, a multiprofessional QI-team was formed. To identify waste and areas for improvement, process mapping and lead time analysis were conducted during a collaborative learning approach. A focus group interview was carried out with the participants in the QI-intervention and the local managers, and a qualitative content analysis of the focus group transcript was performed. ResultsBest practise was gradually introduced, and overall access was improved, but TAT was not changed. Four key factors for CQI were revealed; Communication, Engagement, Context, and Patient- and Customer focus. Moreover, the impact of providing useful and reliable measurements to the frontline staff was found to be high DiscussionThe lack of decreased TAT indicates that further redesign of the radiology process is needed. As the impact of measurements was considered high, an improved system for obtaining and providing useful information to all parts in the organization is essential. Moreover, the infrastructure for CQI needs to be developed further, e.g. by clarifying roles, educating in improvement knowledge, and developing multiprofessional meetings. Finally, motivating and engaging staff is crucial to improve healthcare. It is important with a deeper understanding what triggers this, patient centeredness could be one.

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Behrad, Shanay. "Slice specific authentication and access control for 5G." Electronic Thesis or Diss., Institut polytechnique de Paris, 2020. http://www.theses.fr/2020IPPAS007.

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La cinquième génération de réseaux cellulaires mobiles, 5G, est conçue pour prendre en charge un ensemble de nouveaux cas d'utilisation et exigences, par exemple concernant la qualité de service ou la sécurité. En utilisant les technologies de virtualisation et le concept de découpage de réseau, les opérateurs de réseau 5G seront en mesure de fournir des capacités de connectivité spécifiques afin de prendre en charge ces différents cas d'utilisation. Chaque tranche de réseau (network slice) peut être dédiée à un tiers (c'est-à-dire tout acteur commercial qui n'est pas l'opérateur de réseau) et être conçue pour répondre à ses besoins.Cependant, bien que les tranches de réseau puissent être conçues en activant ou en désactivant certaines fonctions réseau, les mécanismes d'authentification et de contrôle d'accès (AAC) restent les mêmes pour toutes les tranches, avec des composants réseau étroitement couplés.Cette thèse propose 5G-SSAAC (5G Slice-Specific AAC), comme première étape pour introduire une conception à couplage plus lâche dans l'ensemble de l'architecture de réseau 5G. 5G-SSAAC permet aux réseaux 5G de fournir divers mécanismes AAC aux tiers selon leurs exigences de sécurité. Pour évaluer ce mécanisme innovant, la thèse analyse les conséquences de l'utilisation du 5G-SSAAC sur la sécurité de l'ensemble du système 5G. La faisabilité du 5G-SSAAC est également présentée avec la mise en œuvre d'un réseau mobile entièrement virtualisé via un banc d'essai basé sur OAI (Open Air Interface). Ce travail évalue enfin l'impact du mécanisme 5G-SSAAC sur la charge du réseau compte tenu du nombre prévu de messages de signalisation AAC par rapport aux mécanismes AAC existants dans les réseaux cellulaires The fifth generation of mobile cellular networks, 5G, is designed to support a set of new use cases and requirements, e.g. concerning quality of service or security. Using the virtualization technologies and the concept of network slicing, the 5G network operators will be able to provide specific connectivity capabilities in order to support these various use cases. Each network slice can be dedicated to a 3rd party (i.e., any business actor that is not the network operator), and be designed to fit its requirements.However, although network slices can be designed by enabling or disabling certain network functions, the Authentication and Access Control (AAC) mechanisms remain the same for all slices, with tightly coupled network components.This thesis proposes 5G-SSAAC (5G Slice-Specific AAC), as an initial step to introduce a more loosely coupled design into the whole 5G network architecture. 5G-SSAAC enables 5G networks to provide various AAC mechanisms to the 3rd parties according to their security requirements. To assess this innovative mechanism, the thesis analyses the consequences of using the 5G-SSAAC on the security of the whole 5G system. The feasibility of the 5G-SSAAC is also presented with the implementation of a fully virtualized mobile network through an OAI (Open Air Interface) based testbed. This work finally evaluates the impact of 5G-SSAAC mechanism on the network load considering the anticipated number of AAC signalling messages compared to the existing AAC mechanisms in cellular networks

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Alotaibi, Sara Jeza. "Towards a framework and model for acceptable user experiences in e-government physical and virtual identity access management systems." Thesis, University of Southampton, 2013. https://eprints.soton.ac.uk/365154/.

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The wide spread of services on the internet has aggravated the issue of maintaining multiple identities such as the virtual identities that are based on specific login credentials like username, passwords and PINs. On the other hand, multiple physical identities also prove to be difficult to maintain since different sources require the presence of different smart cards, mobile devices or other proofs of identity. Therefore, the modern world is populated with so many virtual and physical Identity Access Management Systems (IAMS) that individuals are required to maintain multiple passwords and login credentials. The tedious task of remembering these can be minimised through the utilisation of an innovative approach of single sign-in mechanisms. During recent times, several systems have been developed to provide physical and virtual IAMS; however, most have not been very successful according to specific criteria. Furthermore, alongside increasing the level of awareness for the need to deploy interoperable physical and virtual IAMS, there exists an immediate need for the establishment of clear guidelines for the successful integration of the two media. The importance of and motivation for the integration of the two media will be discussed in this thesis with respect to three perspectives: security, which includes identity; user experience, comprising usability; and acceptability, containing accessibility. Not many frameworks and models abide by all guidelines for all of these perspectives; thus, the thesis addresses the immediate need to establish a framework and a model for acceptable user experience for successful integration of the two media for public services within the e-government domain. The IAMS framework is based on the attributes from the researched theories of the three perspectives and expert evaluations of the unique nine themes. Regarding the users evaluation to test the proposed Unified Theory of Acceptance and Use of Technology Model(UTAUT), there is an indirect effect on behavioural intentions to use a new prototype system (Ubiquitous Identity Access Management System "UbIAMS") through performance expectancy, effort expectancy, social influence, and through items pertaining to acceptability and user experience.

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Cote, ̕. Richard Scott. "Implementation considerations for a Virtual Private Network (VPN) to enable broadband secure remote access to the Naval Postgraduate School Intranet /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2000. http://handle.dtic.mil/100.2/ADA386706.

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Thesis (M.S. in Information Technology Management) Naval Postgraduate School, Dec. 2000. Thesis advisors, Rex Buddenberg, Daniel Warren. "December 2000." Includes bibliographical references (p. 81-82). Also available in print.

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Cote, Richard Scott. "Implementation considerations for a Virtual Private Network (VPN) to enable broadband secure remote access to the Naval Postgraduate School Intranet." Thesis, Monterey, California. Naval Postgraduate School, 2000. http://hdl.handle.net/10945/9179.

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As broadband connections to the home become more prevalent, through Digital Subscriber Lines (DSL) and cable modems, students and faculty will desire to access the NPS Internet via these new means instead of their 56K modems. The introduction of these new technologies will require NPS to re- evaluate how to allow remote access to their internal resources in a secure way, while still allowing for the use of broadband technologies. This thesis will examine the alternative methods for implementing VPNs, from simple use of Point to Point Protocols (PPP) to high end specialized internet appliances and gateways. Pros and cons of each will be discussed. A mock-up of the schools network will be created to test each of the discussed methods. Final recommendations will be made for a model that can be used by the NPS to implement a VPN. Also discussed will be how that model may be altered to fit other commands throughout the US Navy who desire similar secure remote access to their internal network resources.

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Sigwele, Tshiamo. "Energy Efficient Cloud Computing Based Radio Access Networks in 5G. Design and evaluation of an energy aware 5G cloud radio access networks framework using base station sleeping, cloud computing based workload consolidation and mobile edge computing." Thesis, University of Bradford, 2017. http://hdl.handle.net/10454/16062.

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Fifth Generation (5G) cellular networks will experience a thousand-fold increase in data traffic with over 100 billion connected devices by 2020. In order to support this skyrocketing traffic demand, smaller base stations (BSs) are deployed to increase capacity. However, more BSs increase energy consumption which contributes to operational expenditure (OPEX) and CO2 emissions. Also, an introduction of a plethora of 5G applications running in the mobile devices cause a significant amount of energy consumption in the mobile devices. This thesis presents a novel framework for energy efficiency in 5G cloud radio access networks (C-RAN) by leveraging cloud computing technology. Energy efficiency is achieved in three ways; (i) at the radio side of H-C-RAN (Heterogeneous C-RAN), a dynamic BS switching off algorithm is proposed to minimise energy consumption while maintaining Quality of Service (QoS), (ii) in the BS cloud, baseband workload consolidation schemes are proposed based on simulated annealing and genetic algorithms to minimise energy consumption in the cloud, where also advanced fuzzy based admission control with pre-emption is implemented to improve QoS and resource utilisation (iii) at the mobile device side, Mobile Edge Computing (MEC) is used where computer intensive tasks from the mobile device are executed in the MEC server in the cloud. The simulation results show that the proposed framework effectively reduced energy consumption by up to 48% within RAN and 57% in the mobile devices, and improved network energy efficiency by a factor of 10, network throughput by a factor of 2.7 and resource utilisation by 54% while maintaining QoS.

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Atwaters, Sybrina Yvonne. "Redefining the sacred in 3D virtual worlds: exploratory analysis of knowledge production and innovation through religious expression." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/53048.

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This dissertation contributes to conversations regarding the impact of open user centered innovation on cultural production by focusing on the construction and production of religious products within one large-scale open user-centered technological environment, 3D virtual worlds. Particularly, this study examines how virtual world users construct (non-gaming) religious communities and practices and how the technology impacts the forms of religious expression these users create. Due to its existing religious sector and affordances for user-created content, Second Life (SL) was chosen as the context of study for this dissertation project. Building upon Von-Hippel's (2005) user-centered innovation theory, construction and production within three different user-centered religious communities in SL were explored. Using a comparative ethnographic approach over a 14-month period, involving participant observations, interviews and hyper-media techniques, the social construction of customized religious products amidst technical, social, and economic virtual/non-virtual structures were analyzed. Exploratory findings demonstrate that the democratizing of cultural innovation, that is the construction of heterogeneous cultural religious products by the everyday user, is a matter of patterned relational pathways. The greater possible patterned pathways the higher potential for democratized cultural innovation, an increasing number of users developing new ways of doing religion. The fewer patterned pathways the less the potential for democratize cultural innovation and the greater potential for reproducing within the virtual realm the same cultural frames that define the current social order in the non-virtual realm.

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Abdulwahed, Mahmoud. "Towards enhancing laboratory education by the development and evaluation of the "TriLab" : a triple access mode (virtual, hands-on and remote) laboratory." Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/6355.

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This thesis contributes to the general body of knowledge of research into engineering education. The main scope of the thesis is on enhancing laboratory education. There are three main types of laboratory: virtual, hands-on and remote. The hands-on lab is the oldest and most commonly used medium for experiential education in undergraduate degrees of science and engineering. The literature review of laboratory education has shown that hands-on labs suffer from many disadvantages, which can be overcome by utilizing hybrid laboratory structures that incorporate virtual and/or remote modes. The investigation into enhanced laboratory education is achieved via implementing new technical and pedagogical models of conducting laboratories. The technical model incorporates three access modes (virtual, hands-on and remote) to the laboratory experience in one software package called the TriLab. The TriLab concept has been applied to the Process Control Lab at the Chemical Engineering Department of Loughborough University and has been implemented using LabVIEW. The Joomla web content management system was used to develop an online portal for disseminating the remote component of the TriLab resulting in the first remote lab portal of Loughborough University and one of the few available in the UK. A pedagogical model of laboratory education based on Kolb's experiential learning theory and by the utilization of the TriLab concept is proposed. The model is built on a hypothesis, which states that the poor learning outcomes of hands-on laboratory sessions can be associated with poor activation of the stages of Kolb's experiential learning cycle. It has been proposed that access to a virtual lab in a preparatory session will play a role in activating the stages of Kolb's cycle. To verify this, educational experimentation procedures were designed and applied to two groups, control and experimental. Measurements via pre- and post-lab tests, marks for the laboratory report and the final exam of the module have been performed. The statistical analysis of the measurements has supported the stated hypothesis and solution proposal. The proposed pedagogical model is one of the few that provide a way of conducting laboratory education based on constructivist educational theories. (Continues...).

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Hibbard, Laura E. "Student Literature Access in an Online School: A Program Evaluation." Ohio University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1375807647.

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Downing, Thomas A. "An Initial Survey and Description of How Selected United States Government Libraries, Information Centers, and Information Services Provide Public Access to Information Via the Internet." the Library of Congress, 2000. http://hdl.handle.net/10150/105137.

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The purpose of this survey is to describe how selected United States Government agencies provide information to the public via Internet services. With more than 2,000 Federal library and information centers located throughout the world this effort, of necessity, is selective and findings neither represent all libraries nor do they identify all approaches currently used to present information via the Web. An effort has been made to describe services without attributing values to particular site characteristics. This report provides a brief snapshot in time of a complex and rapidly evolving world. While not definitive in scope, it is hoped that this report will provide a baseline for anyone who may wish to revisit some of these sites in the future to determine how services may have been expanded, reduced, or refined.

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Tabassum, Mujahid, and Khamees Elkhateeb. "Network Capability Analysis and Related Implementations Improvements Recommendations." Thesis, Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-2476.

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The networking field has become a core component for any company. All of thebusinesses rely on the networking industry, due its vastness and significance. Every daycompanies are planning and thinking to develop better strategies that can offer efficientand reliable communication solutions between their employees and customers formaximum revenue. The planning of a company’s network requires a lot of resources andaspects to study, and to evaluate them carefully to build a comprehensive secure andreliable platform. It is the job of a network administrator to take care of the company’snetwork infrastructure and upgrade or update the required components and applicationsfrom time-to-time that can follow new standards.This thesis is a practical work aimed to evaluate a company network infrastructure in itsreal environment. The purpose of this thesis is to evaluate different aspects of thenetwork infrastructure used such as VPN, WLAN, firewall and physical security and giverecommendations to make their performance better and to offer more advanced strategies.This study will also provide an inclusive observation of the company’s needs and theirnetwork infrastructure, and will provide a concept how to evaluate and fix small mistakes,the kind of problems that can occur in an evolving company network. Lastly, this researchwill make recommendations and suggest a possible implementation on the studiednetwork infrastructure.

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Raj, Himanshu. "Virtualization services scalable methods for virtualizing multicore systems /." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22677.

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Thesis (Ph. D.)--Computing, Georgia Institute of Technology, 2008. Committee Chair: Schwan, Karsten; Committee Member: Ahamad, Mustaq; Committee Member: Fujimoto, Richard; Committee Member: Gavrilovska, Ada; Committee Member: Owen, Henry; Committee Member: Xenidis, Jimi.

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Ma, Wenjun. "AMMP-EXTN a user privacy and collaboration control framework for a multi-user collaboratory virtual reality system /." unrestricted, 2007. http://etd.gsu.edu/theses/available/etd-09142007-204819/.

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Thesis (M.S.)--Georgia State University, 2007. Title from file title page. Ying Zhu, committee chair; G.Scott Owen, Robert W. Harrison, committee members. Electronic text (87 p. : ill. (some col.)) : digital, PDF file. Description based on contents viewed Feb. 7, 2008. Includes bibliographical references (p. 84-87).

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Rawlinson, Mark Roland. "Improving access to clinical supervision through action research with community nurses : what are the build and design criteria for an online virtual environment for clinical supervision?" Thesis, University of Southampton, 2011. https://eprints.soton.ac.uk/341113/.

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Access to clinical supervision is an enduring enigma to many nurses and other healthcare professionals. The aim of this action research study was to bring about the potential for a change in the practice of clinical supervision (CS) by developing a solution to the problem of access. This was achieved in collaboration with community nurses and a range of other staff from one NHS Primary Care Trust. The solution proposed was the development of a new mode of delivery: online clinical supervision. Holter and Schwartz-Barcott’s (1993) Technical Collaborative Approach was used to identify potential user (Supervisee, Supervisors and Management) requirements for an online environment for CS. The research was conducted in three stages. The first stage ‘Conceptualisation’ involved the identification and exploration of the problem as well as the initial steps in discovering how the problem could be addressed. Central to this was the engagement with the stakeholders. The second stage ‘Designing the Solution’ was a synthesis of activities undertaken by focus groups in order to determine what a potential online environment might look and feel like, as well as how it might function. Analysis was through a continuous, iterative, cyclical process of member checking. Schach’s (1999) Life Cycle Model (adapted) and Lengel’s (2001) Website Design Principles were used as a theoretical frame to guide the solicitation of the required design and build criteria. The final stage was ‘Evaluation’, participants evaluated the design and build criteria they had developed using a SWOT analysis, and finally the experience of undertaking action research was captured through a self completion questionnaire. In conclusion, this research has identified what an online environment for CS could look like, as well as how it might function, thus opening up the possibility of improving access to CS. The research also highlighted a potential tension between the users’ desire for privacy and the employers’ desire for access to information. Future negotiations are required to determine how this tension could be managed. The likely impact of this development, if implemented, will be more community nurses and others undertaking CS at a time and place that is convenient to them, potentially making CS available (via a user-centred design) 24 hours-a-day, seven days-a-week a reality.

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Tilley, Christine Margaret. "A sense of control : a model of a virtual community for people with mobility impairments." Queensland University of Technology, 2006. http://eprints.qut.edu.au/16308/.

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This qualitative study develops a model of a virtual community for people with longterm, severe physical or mobility disabilities. The model also has implications for the wider community of people with disabilities. The study uses the Strauss and Corbin grounded theory methodology to inform the investigation from which a systematic theory has been developed. On the basis of this theory, the study proposes strategies for implementing the virtual community model. In-depth interviews were conducted with twelve Queenslanders with paraplegia, quadriplegia or other severe, long-term physical or mobility disabilities and with six health care professionals, service providers, information personnel and policy advisers involved in their well-being. The methodology used one interview question to determine their experiences and perceptions regarding virtual communities and the use of Information and Communications Technology (ICT). Each interview explored in detail the elements, enablers and barriers behind the usage of ICT and/or assistive technology. The personal responses and narratives of the people with disabilities who use the technology and their allied health care professionals were analysed and interpreted for meaning before the transcripts were returned to these participants for validation. Rich explanations were derived. Details of the various response categories of these interviews were analysed as part of the grounded theory, constant comparison methodology, and the relationship to the literature was considered. These de-constructed meanings were compared and contrasted with those in the current literature. The central theme to emerge from these narratives is that people with long-term disabilities regain a sense of control and independence in their lives through the use of ICT, as they move towards an on-line community. Other major themes that emerged from being on-line indicated that being on-line tended to break down people's isolation, while potentially changing the work paradigm (both vexed issues for people with disabilities). Information and communications technology and on-line communities offer ways to enhance every person's inclusion, participation and empowerment in our society. The primary outcome of the study is a theory regarding the character of virtual communities for people with long-term, severe mobility impairments that stakeholders may consider whenever such a virtual community is proposed. The theory is represented as a virtual community model. The model identifies the need for "a sense of control" as the foundational element of virtual communities for the disabled, and distinguishes the key domains in which disabled people participate in virtual communities. The barriers and enablers to their participation are specified within it. The model also provides a framework within which virtual communities can be facilitated. It melds six types of e-communities or sets of well-developed discrete categories (for example, themes, concepts) that the data from this study revealed: education-oriented, fantasy-oriented, information-oriented, interestoriented, relationship-oriented and transaction-oriented, depending on the type(s) of consumer need(s) to be met. The study concludes that although the technology itself provides strategies for independence and thus facilitates self-empowerment, it is also capable of being disempowering. Many interviewees referred to this aspect as a "double-edged sword". Empowerment and dis-empowerment are intersecting processes because of digital divide and information literacy issues and this "double-edged sword", which virtual reality presents for people with physical disabilities. Based on the new knowledge and the model as the outcomes of this study, a range of recommendations are discussed that have application in the community for persons with mobility impairments.

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Hermansson, Christopher, and Sebastian Johansson. "Segmentering av lokala nätverk - För mikro- och småorganisationer." Thesis, Linnaeus University, School of Computer Science, Physics and Mathematics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-5903.

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Syftet med den här rapporten är att beskriva ett antal olika tillvägagångssätt man kan använda sig av då man har behov av att dela in ett lokalt nätverk i olika segment och med det även kunna reglera trafikflödet mellan segmenten. De lösningar som presenteras i arbetet är inriktade mot mikro- och småföretag.Anledningen till att vi har valt att arbeta med det här området är att vi anser att det är viktigt för organisationer att har en strukturerad och segmenterad design på sitt interna datornätverk.Vi har arbetat genom att i förväg samla in information om olika tekniker som kan tänkas lösa vårt problem, och därefter testat olika scenarion med dessa tekniker. Data har samlats in efter varje genomfört scenario och sammanställts i statistisk form för att kunna avgöra vilken metod som var att föredra.Vi har testat lösningar där man segmenterar nätverket i en lager 2-switch medan man möjliggör och förhindrar trafikflöde mellan segmenten i en router. Även lösningar där man använder en lager 3-switch har testats. På så sätt kan routningen ske direkt i switchen och det blir betydligt mindre belastning i routern. Resultatet visar att då man vill segmentera ett nätverk så är det rekommenderat att man använder sig av VLAN och ACL:er och eventuellt i kombination med en brandvägg.Slutresultatet av rapporten är att en lösning med ”router on a stick” är den billigaste lösningen och troligen den som de flesta mindre företag skulle klara sig med. Vilken lösning man väljer beror dock helt på hur mycket pengar man vill lägga på sitt nätverk samt vad kraven är. The purpose of this report is to describe a number of approaches that can be used when you are in need of dividing a local area network in a number of segments, and with that also be able to control how data traffic is allowed to traverse between the different segments. The solutions that are presented are focused towards micro and small companies.The reason that we have chosen to work with this matter is that we believe it is important for organizations to have a structured and segmented design of its internal computer network.We have been working by in advance collecting information about various techniques that might solve our problem, and then testing different scenarios using these techniques. Data have been collected after each tested scenario and compiled in statistical form in order to determine which method that was preferable.We have been testing solutions were you segment the network in a layer 2 switch while you allow or deny communication between the segments in a router, and also solutions were you use a layer 3 switch. In that way you can let the routing be performed in the switch, which leads to significantly lower load on the router. The result was that if you are about to segment a local area network it is recommended that you use VLAN and ACL:s, and possibly in combination with a firewall.The final result of this report is that a solution using the “router on a stick”-technique is the cheapest one, and probably the one that most small companies would get along with. However, the solution that you choose depends completely on how much money you want to spend on your network, and also what the needs are.

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Tilley, Christine Margaret. "A sense of control : a model of a virtual community for people with mobility impairments." Thesis, Queensland University of Technology, 2006. https://eprints.qut.edu.au/16308/1/Christine_Tilley_Thesis.pdf.

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This qualitative study develops a model of a virtual community for people with longterm, severe physical or mobility disabilities. The model also has implications for the wider community of people with disabilities. The study uses the Strauss and Corbin grounded theory methodology to inform the investigation from which a systematic theory has been developed. On the basis of this theory, the study proposes strategies for implementing the virtual community model. In-depth interviews were conducted with twelve Queenslanders with paraplegia, quadriplegia or other severe, long-term physical or mobility disabilities and with six health care professionals, service providers, information personnel and policy advisers involved in their well-being. The methodology used one interview question to determine their experiences and perceptions regarding virtual communities and the use of Information and Communications Technology (ICT). Each interview explored in detail the elements, enablers and barriers behind the usage of ICT and/or assistive technology. The personal responses and narratives of the people with disabilities who use the technology and their allied health care professionals were analysed and interpreted for meaning before the transcripts were returned to these participants for validation. Rich explanations were derived. Details of the various response categories of these interviews were analysed as part of the grounded theory, constant comparison methodology, and the relationship to the literature was considered. These de-constructed meanings were compared and contrasted with those in the current literature. The central theme to emerge from these narratives is that people with long-term disabilities regain a sense of control and independence in their lives through the use of ICT, as they move towards an on-line community. Other major themes that emerged from being on-line indicated that being on-line tended to break down people's isolation, while potentially changing the work paradigm (both vexed issues for people with disabilities). Information and communications technology and on-line communities offer ways to enhance every person's inclusion, participation and empowerment in our society. The primary outcome of the study is a theory regarding the character of virtual communities for people with long-term, severe mobility impairments that stakeholders may consider whenever such a virtual community is proposed. The theory is represented as a virtual community model. The model identifies the need for "a sense of control" as the foundational element of virtual communities for the disabled, and distinguishes the key domains in which disabled people participate in virtual communities. The barriers and enablers to their participation are specified within it. The model also provides a framework within which virtual communities can be facilitated. It melds six types of e-communities or sets of well-developed discrete categories (for example, themes, concepts) that the data from this study revealed: education-oriented, fantasy-oriented, information-oriented, interestoriented, relationship-oriented and transaction-oriented, depending on the type(s) of consumer need(s) to be met. The study concludes that although the technology itself provides strategies for independence and thus facilitates self-empowerment, it is also capable of being disempowering. Many interviewees referred to this aspect as a "double-edged sword". Empowerment and dis-empowerment are intersecting processes because of digital divide and information literacy issues and this "double-edged sword", which virtual reality presents for people with physical disabilities. Based on the new knowledge and the model as the outcomes of this study, a range of recommendations are discussed that have application in the community for persons with mobility impairments.

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42

Ben, Salem Aymen. "The Application of Multiuser Detection to Spectrally Efficient MIMO or Virtual MIMO SC-FDMA Uplinks in LTE Systems." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/30351.

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Single Carrier Frequency Division Multiple Access (SC-FDMA) is a multiple access transmission scheme that has been adopted in the 4th generation 3GPP Long Term Evolution (LTE) of cellular systems. In fact, its relatively low peak-to-average power ratio (PAPR) makes it ideal for the uplink transmission where the transmit power efficiency is of paramount importance. Multiple access among users is made possible by assigning different users to different sets of non-overlapping subcarriers. With the current LTE specifications, if an SC-FDMA system is operating at its full capacity and a new user requests channel access, the system redistributes the subcarriers in such a way that it can accommodate all of the users. Having less subcarriers for transmission, every user has to increase its modulation order (for example from QPSK to 16QAM) in order to keep the same transmission rate. However, increasing the modulation order is not always possible in practice and may introduce considerable complexity to the system. The technique presented in this thesis report describes a new way of adding more users to an SC-FDMA system by assigning the same sets of subcarriers to different users. The main advantage of this technique is that it allows the system to accommodate more users than conventional SC-FDMA and this corresponds to increasing the spectral efficiency without requiring a higher modulation order or using more bandwidth. During this work, special attentions wee paid to the cases where two and three source signals are being transmitted on the same set of subcarriers, which leads respectively to doubling and tripling the spectral efficiency. Simulation results show that by using the proposed technique, it is possible to add more users to any SC-FDMA system without increasing the bandwidth or the modulation order while keeping the same performance in terms of bit error rate (BER) as the conventional SC-FDMA. This is realized by slightly increasing the energy per bit to noise power spectral density ratio (Eb/N0) at the transmitters.

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Digiere, Adriano Ricardo. "Camada de gerenciamento para comunicação entre computadores baseada em redes sem fio (WSE-OS) /." São José do Rio Preto : [s.n.], 2011. http://hdl.handle.net/11449/98660.

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Orientador: Roberta Spolon Banca: João Paulo Papa Banca: Regina Helena Carlucci Santana Resumo: O maior custo de propriedade de computadores não é o hardware ou o software, mas sim o tempo que os profissionais de informática gastam em suporte e manutenção dos ambientes computacionais. Em um conglomerado de computadores em rede, cada computador torna- se uma entidade gerenciada individualmente, o que gera contínuas solicitações de alterações de configuração, como instalação de atualizações de software, conexão e configuração de periféricos, criação de perfis de e-mail e aplicação de patches. Além disso, existe ainda o risco de furto de dados e invasão por hackers quando os computadores dos usuários não estão protegidos. Aliado a este cenário, a constante evolução dos sistemas computacionais e seu potencial de processamento, a cada dia são necessárias novas técnicas de aproveitamento destes recursos. Soluções que visam facilitar o gerenciamento de ambientes com grande massa de computadores de forma a tirar o máximo proveito do poder computacional concentrado em servidores já se tornaram necessidades reais, não só em grandes corporações, mas também em pequenas e médias empresas, além de outros tipos organizações, como por exemplo, instituições de ensino. Frente esta necessidade, focando uma ferramenta compatível neste cenário de crescimento, este trabalho apresenta um modelo de gerenciamento centralizado, nomeado WSE-OS (Wireless Sharing Environment - Operating Systems), baseado em técnicas de virtualização e acesso remoto seguro combinadas a um sistema de arquivos remotos em espaço de usuário. Esta solução elimina a necessidade da instalação e configuração de aplicativos "máquina a máquina", além de tirar maior proveito do poder computacional existente nos servidores. A principal característica deste modelo que o destaca das soluções atuais é que ele é especificamente elaborado para operar sobre redes... (Resumo completo, clicar acesso eletrônico abaixo) Abstract: The largest cost of desktop ownership is not the hardware or software, but the time that administrators spend on support and maintenance of computing environments. In a conglomerate of computers in a network, each computer becomes an entity managed individually, which generates continuous requests for configuration changes, such as installing software updates, configuration and connection of peripherals, profiling email and applying patches. Moreover, there is the risk of data theft and hacking when users' computers are not protected. Allied to this scenario, the constant evolution of computer systems and their potential for processing, each day requires new techniques for exploitation of these resources. Solutions aimed facilitating the management of environments with large mass of computers to take maximum advantage of computing power concentrated on servers have become real needs, not only in large corporations but also small and medium enterprises, besides other types organizations, such as educational institutions. Facing this need, focusing on a tool that supported this growth scenario, this work presents a centralized management model, named WSE-OS (Wireless Sharing Environment - Operating Systems) based on virtualization techniques and secure remote access combined with a remote file system in user space. This solution eliminates the need for installing and configuring applications "machine to machine", besides take greater advantage of existing computing power on the servers . The main feature of this model that highlights the current solutions is that it is specifically designed to operate on networks with low transmission rates, such as wireless networks. The WSE-OS is able to perform the replication of operating system images in an environment with WLAN communication, which makes management more flexible and independent of physical connections, besides offer... (Complete abstract click electronic access below) Mestre

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Crepaldi, Luis Gustavo. "Middleware de comunicação entre objetos distribuídos para gerenciamento de computadores baseado em redes sem fio (WSE-OS) /." São José do Rio Preto : [s.n.], 2011. http://hdl.handle.net/11449/98663.

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Resumo: Para simplificar o gerenciamento de computadores, vários sistemas de administração estruturados por conexões físicas adotam técnicas avançadas para gestão de configuração de software. No entanto, a forte ligação entre hardware e o software faz com que haja uma individualização desta gerência, além da penalização da mobilidade e ubiqüidade do poder computacional. Neste cenário, cada computador torna-se uma entidade individual a ser gerenciada, exigindo operações manuais de configuração da imagem de sistema. Tecnologias que oferecem gestão centralizada baseadas em conexões físicas cliente-servidor, combinando técnicas de virtualização com a utilização de sistemas de arquivos distribuídos, refletem a degradação em flexibilidade e facilidade de instalação deste sistema gerenciador. Outras arquiteturas para gerenciamento centralizado que estruturam o compartilhamento de dados através de conexões físicas e dependem do protocolo PXE, apresentam os mesmos impasses descritos anteriormente. Diante das limitações dos modelos de gerenciamento centralizado baseado em conexões físicas, o objetivo deste trabalho é o desenvolvimento de um middleware de comunicação cliente-servidor como parte integrante e necessária para um ambiente de gerenciamento centralizado em redes de comunicações sem fio. Este ambiente, denominado WSE-OS (Wireless Sharing Enviroment ? Operating Systems), é um modelo baseado Virtual Desktop Infrastructure (VDI) que associa técnicas de virtualização e sistema de acesso remoto seguro para criação de uma arquitetura distribuída como base de um sistema de gestão. WSE-OS é capaz de realizar a replicação de sistemas operacionais em um ambiente de comunicação sem fio além de oferecer abstração de hardware aos clientes. O WSE-OS pode substituir o boot local com disco rígido por um boot de uma Imagem de Sistema Única... (Resumo completo, clicar acesso eletrônico abaixo) Abstract: To simplify computer management, various administration systems structured with physical connections adopt advanced techniques to manage software configuration. Nevertheless, the strong link between hardware and software makes for an individualism of that management, besides penalizing computational mobility and ubiquity. In this scenario, each computer becomes an individual entity to be managed, requiring manual operations of the system image configuration. Technologies that offer centralized management based on client-server physical connections, combining virtualization techniques with the use of distributed file systems in clusters with distributed processing on network computers reflect the deterioration in flexibility and ease of installation and maintenance of distributed applications. Other architectures for centralized management that structure the sharing of data through physical connections and depend on the PXE protocol, present the same dilemmas described above. Given the limitations models of centralized management based on physical connections, the objective of this project is the development of a middleware for client-server communication as part necessary of an environment for centralized management in wireless communications networks. This environment, called WSE-OS (Wireless Sharing Environment ? Operating Systems), is a model based Virtual Desktop Infrastructure (VDI), which combines virtualization techniques and secure access system for creating a distributed architecture as the basis for a management system. WSE-OS is capable of replicating operating systems in a wireless environment, addition to providing hardware abstraction to clients. The WSE-OS can replace the boot with local hard disk to a boot from SSI (Single System Image) virtualized in server via communication middleware, increasing flexibility and allowing multiple operating systems... (Complete abstract click electronic access below) Orientador: Marcos Antônio Cavenaghi Coorientador: Roberta Spolon Banca: João Paulo Papa Banca: Regina Helena Carlucci Santana Mestre

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Conocimiento, Dirección de Gestión del. "Guía de acceso para OECD - Biblioteca Virtual." Organización para la Cooperación y el Desarrollo Económicos (OCDE), 2021. http://hdl.handle.net/10757/655368.

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Pettersson, Erik. "The Buffer - direktåtkomst av minnesbuffer för ljudspår." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-49067.

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Modulära synthesizers blev en stor kommerciell succé in på 1960-talet som sedan in på 2010-talet skulle få uppmärksamhet på nytt, troligtvis i samband med en "Do it yourself-rörelse" (DIY-movement). En sampler är ett instrument som finns både självständigt och som styrspänningskontrollerad modul inom modulärsyntes. Vanligt är att vissa aspekter till uppspelning går att kontrollera med styrspänning, exempelvis uppspelningshastigheten. Något varken jag eller min handledare har sett tidigare är direktåtkomst med styrspänning till minnespekare i en ljudbuffer för samplermoduler. Därför implementerade jag The Buffer, en samplermodul i en virtuell modulärsyntesmiljö - VCV Rack. I arbetet undersökte jag två frågeställningar: kopplingen mellan inspänningen till modulen och det resulterande ljudet, samt även vilket maximalt minnesområde som går att adressera för styrspänningen så att pekarna sveper konsekutivt genom varje frame av ljudspåret. I den senare utforskade jag två möjliga svar, ett teoretiskt största möjliga, och ett med utgångspunkt i min implementation. Jag utförde även en användarstudie på mer subjektiv basis för en indikation på modulens användbarhet.

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Camas, Nuria Pons Vilardell. "Revista e-Curriculum: origens e evolução de um periódico científico eletrônico na área de educação e currículo construído na colaboração pedagógica." Pontifícia Universidade Católica de São Paulo, 2008. https://tede2.pucsp.br/handle/handle/10066.

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Made available in DSpace on 2016-04-27T14:32:15Z (GMT). No. of bitstreams: 1 Nuria Pons Vilardell Camas.pdf: 4448227 bytes, checksum: 9d02f580b32fe997a778b458b62b38f8 (MD5) Previous issue date: 2008-05-30 Conselho Nacional de Desenvolvimento Científico e Tecnológico This study lies in the New Technologies and Education line of research and aims at describing and analyzing the process of producing an electronic journal on Education and Curriculum, by a group of students of the PhD Program of Postgraduate Education: Curriculum 2004 of PUC-SP. The work establishes a broad dialogue with several authors who reflect on the history of scientific publication, the evolution of magazines printed for the electronic media, especially the digital ones, the current principles of science for dissemination, the virtual reading, open access, and the curricular narrative. The instruments for collecting data were the researcher's field diary, the list of discussion created for the group of instructors from e-Curriculum magazine, recorded chats, recorded videos, testimonial e-mail of the subjects, letters of indexing organizations and a CD-ROM of the historical archives of e-Curriculum magazine. The research on the participatory action model provided the necessary engagement to hear the speeches of subjects who lived intensely the universe of the creation of a journal, enabling to confirm that, from the subject-authors perspective, the technological media are spaces of preparation and creation of new locations for the spread and dissemination of research, as spaces for learning socialization. The thesis shows that the electronic journals, in any area of knowledge, need to be explained through research for their existence. The investigation indicates that it is possible to create a journal in postgraduate programs and concludes that it is necessary to open up intense dialogues in these programs for the development of science in the country. It is not enough to produce magazines without their correspondent political-pedagogical effort for their use and effectiveness in the research domain. Finally, it was concluded that it is possible to construct a curricular narrative from the journey, from the search for the construction of pedagogical and social utopias, without losing or failing to develop the prescriptive curriculum Este estudo situa-se na linha de pesquisa Novas Tecnologias e Educação, procura descrever e anal isar o processo de const rução de uma revista cientí fica elet rônica em Educação e Currículo, por um grupo de alunos do Doutorado do Programa de Pós-graduação Educação: Currículo de 2004 da PUC-SP. O trabalho estabelece amplo diálogo com diversos autores que refletem sobre a história da publicação cientí fica, a evolução das revistas impressas para os meios eletrônicos, especialmente os digitais, os princípios regentes de ciência para disseminação, sobre a leitura vi rtual , o acesso aberto, ou como se conhece, do open access, e da narrativa curricular. Como instrumentos de recolhas de dados ut ilizaram-se o diário itinerante da pesquisadora, a lista de discussão criada para o grupo formador da Revista e-Curriculum, chat gravados, gravações em vídeo, emai l depoimento dos sujeitos, cartas de órgãos indexadores e CD-ROM dos arquivos históricos da Revista e-Curriculum. A pesquisa em modelo de ação participava propiciou o engajamento necessário para ouvir os discursos de sujeitos que viveram intensamente o universo da construção de um periódico cientí fico, sendo possível confirmar que, pela perspectiva destes sujeitos-autores, os suportes tecnológicos se constituem em espaços de elaboração e de criação de novos locais para a disseminação e divulgação de pesquisas, como espaços de social ização das aprendizagens. A tese aponta que os periódicos eletrônicos, em qualquer área do conhecimento, necessitam serem significados por meio de pesquisa para sua existência. A investigação aponta que é possível const rui r um periódico em programas de pós-graduação e conclui que é necessário abri r-se diálogos intensos nestes programas para o desenvolvimento da ciência no país. Não é suficiente lançar revistas sem o correspondente t rabalho político-pedagógico para seu uso e eficácia no domínio da pesquisa. Por fim, foi concluído que é possível construi r uma narrativa curricular a parti r do t rajeto, da busca para a construção de utopias pedagógicas e sociais, sem perder ou deixar de se desenvolver o currículo prescritivo

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Conocimiento, Dirección de Gestión del. "Guía de acceso para Sala de Lectura Virtual - Inacal." Inacal, 2021. http://hdl.handle.net/10757/655382.

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Digiere, Adriano Ricardo [UNESP]. "Camada de gerenciamento para comunicação entre computadores baseada em redes sem fio (WSE-OS)." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/98660.

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Made available in DSpace on 2014-06-11T19:29:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-03-31Bitstream added on 2014-06-13T19:59:30Z : No. of bitstreams: 1 digiere_ar_me_sjrp.pdf: 1496121 bytes, checksum: 2cc2450b0bec5e0610a6820222483893 (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) O maior custo de propriedade de computadores não é o hardware ou o software, mas sim o tempo que os profissionais de informática gastam em suporte e manutenção dos ambientes computacionais. Em um conglomerado de computadores em rede, cada computador torna- se uma entidade gerenciada individualmente, o que gera contínuas solicitações de alterações de configuração, como instalação de atualizações de software, conexão e configuração de periféricos, criação de perfis de e-mail e aplicação de patches. Além disso, existe ainda o risco de furto de dados e invasão por hackers quando os computadores dos usuários não estão protegidos. Aliado a este cenário, a constante evolução dos sistemas computacionais e seu potencial de processamento, a cada dia são necessárias novas técnicas de aproveitamento destes recursos. Soluções que visam facilitar o gerenciamento de ambientes com grande massa de computadores de forma a tirar o máximo proveito do poder computacional concentrado em servidores já se tornaram necessidades reais, não só em grandes corporações, mas também em pequenas e médias empresas, além de outros tipos organizações, como por exemplo, instituições de ensino. Frente esta necessidade, focando uma ferramenta compatível neste cenário de crescimento, este trabalho apresenta um modelo de gerenciamento centralizado, nomeado WSE-OS (Wireless Sharing Environment – Operating Systems), baseado em técnicas de virtualização e acesso remoto seguro combinadas a um sistema de arquivos remotos em espaço de usuário. Esta solução elimina a necessidade da instalação e configuração de aplicativos “máquina a máquina”, além de tirar maior proveito do poder computacional existente nos servidores. A principal característica deste modelo que o destaca das soluções atuais é que ele é especificamente elaborado para operar sobre redes... The largest cost of desktop ownership is not the hardware or software, but the time that administrators spend on support and maintenance of computing environments. In a conglomerate of computers in a network, each computer becomes an entity managed individually, which generates continuous requests for configuration changes, such as installing software updates, configuration and connection of peripherals, profiling email and applying patches. Moreover, there is the risk of data theft and hacking when users' computers are not protected. Allied to this scenario, the constant evolution of computer systems and their potential for processing, each day requires new techniques for exploitation of these resources. Solutions aimed facilitating the management of environments with large mass of computers to take maximum advantage of computing power concentrated on servers have become real needs, not only in large corporations but also small and medium enterprises, besides other types organizations, such as educational institutions. Facing this need, focusing on a tool that supported this growth scenario, this work presents a centralized management model, named WSE-OS (Wireless Sharing Environment – Operating Systems) based on virtualization techniques and secure remote access combined with a remote file system in user space. This solution eliminates the need for installing and configuring applications machine to machine, besides take greater advantage of existing computing power on the servers . The main feature of this model that highlights the current solutions is that it is specifically designed to operate on networks with low transmission rates, such as wireless networks. The WSE-OS is able to perform the replication of operating system images in an environment with WLAN communication, which makes management more flexible and independent of physical connections, besides offer... (Complete abstract click electronic access below)

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Crepaldi, Luis Gustavo [UNESP]. "Middleware de comunicação entre objetos distribuídos para gerenciamento de computadores baseado em redes sem fio (WSE-OS)." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/98663.

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Made available in DSpace on 2014-06-11T19:29:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-03-31Bitstream added on 2014-06-13T18:59:19Z : No. of bitstreams: 1 crepaldi_lg_me_sjrp.pdf: 1446703 bytes, checksum: 5212981cdddeca5acc9e64906c893d50 (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Universidade Estadual Paulista (UNESP) Para simplificar o gerenciamento de computadores, vários sistemas de administração estruturados por conexões físicas adotam técnicas avançadas para gestão de configuração de software. No entanto, a forte ligação entre hardware e o software faz com que haja uma individualização desta gerência, além da penalização da mobilidade e ubiqüidade do poder computacional. Neste cenário, cada computador torna-se uma entidade individual a ser gerenciada, exigindo operações manuais de configuração da imagem de sistema. Tecnologias que oferecem gestão centralizada baseadas em conexões físicas cliente-servidor, combinando técnicas de virtualização com a utilização de sistemas de arquivos distribuídos, refletem a degradação em flexibilidade e facilidade de instalação deste sistema gerenciador. Outras arquiteturas para gerenciamento centralizado que estruturam o compartilhamento de dados através de conexões físicas e dependem do protocolo PXE, apresentam os mesmos impasses descritos anteriormente. Diante das limitações dos modelos de gerenciamento centralizado baseado em conexões físicas, o objetivo deste trabalho é o desenvolvimento de um middleware de comunicação cliente-servidor como parte integrante e necessária para um ambiente de gerenciamento centralizado em redes de comunicações sem fio. Este ambiente, denominado WSE-OS (Wireless Sharing Enviroment ? Operating Systems), é um modelo baseado Virtual Desktop Infrastructure (VDI) que associa técnicas de virtualização e sistema de acesso remoto seguro para criação de uma arquitetura distribuída como base de um sistema de gestão. WSE-OS é capaz de realizar a replicação de sistemas operacionais em um ambiente de comunicação sem fio além de oferecer abstração de hardware aos clientes. O WSE-OS pode substituir o boot local com disco rígido por um boot de uma Imagem de Sistema Única... To simplify computer management, various administration systems structured with physical connections adopt advanced techniques to manage software configuration. Nevertheless, the strong link between hardware and software makes for an individualism of that management, besides penalizing computational mobility and ubiquity. In this scenario, each computer becomes an individual entity to be managed, requiring manual operations of the system image configuration. Technologies that offer centralized management based on client-server physical connections, combining virtualization techniques with the use of distributed file systems in clusters with distributed processing on network computers reflect the deterioration in flexibility and ease of installation and maintenance of distributed applications. Other architectures for centralized management that structure the sharing of data through physical connections and depend on the PXE protocol, present the same dilemmas described above. Given the limitations models of centralized management based on physical connections, the objective of this project is the development of a middleware for client-server communication as part necessary of an environment for centralized management in wireless communications networks. This environment, called WSE-OS (Wireless Sharing Environment ? Operating Systems), is a model based Virtual Desktop Infrastructure (VDI), which combines virtualization techniques and secure access system for creating a distributed architecture as the basis for a management system. WSE-OS is capable of replicating operating systems in a wireless environment, addition to providing hardware abstraction to clients. The WSE-OS can replace the boot with local hard disk to a boot from SSI (Single System Image) virtualized in server via communication middleware, increasing flexibility and allowing multiple operating systems... (Complete abstract click electronic access below)

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