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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Identity Management in a Fixed Mobile convergent IMS environment

Nguyen, Trung Kien January 2008 (has links)
<p>Today, there are still different technologies used in fixed and mobile networks environment such as cellular technologies (GSM, UMTS, 3G, etc.), wireless network technology like WLAN, wired network technology like ADSL, etc. With the usage of IMS (IP Multimedia Subsystem), all those technologies can be combined together in a fixed mobile convergence environment based on an IP-based infrastructure. Although IMS applies well for a Fixed Mobile convergent environment, there are still issues that need to be solved. First, the IMS central protocol is SIP but there are differences between the 3GPP SIP specifications and the IETF one. This will lead to interoperability problem with different SIP specifications, and the devices between different SIP environments cannot communicate with each other. Second, IMS for a fixed mobile environment should also allow the users to subscribe to any type of services (fixed or mobile), to get access to services on an arbitrary number of registered mobile and fixed devices interchangeably, to dynamically add or remove the number of registered fixed devices. In fact, the general IMS infrastructure is only a high-level scheme and does not support the mentioned requirements. Therefore, in order to satisfy all the mentioned requirements it is crucial to have a sound identity management solution. The goal of this thesis work is to propose a sound identity management solution for a fixed mobile convergent IMS environment. More specifically, the thesis work will be aiming at the following objectives: • To provide a concise but clear introduction to Identity Management • To provide a comprehensive description on how identities are organized and managed in both fixed and mobile networks • To propose an identity management solution for a fixed mobile convergent IMS environment • To demonstrate the soundness and feasibility of the proposed solution via the implementation of a prototype. Two Identity Management solutions have been proposed and analyzed as follows: 1. Modified IMS and SSO-enabled SIP system 2. Modified SIP-enabled Client Due to time limitation, only the second solution is selected and a proof-of concept has been successfully designed and implemented. The proof-of-concept has demonstrates the following features: • Single-Sign-On between the Mobile and Fixed domain enabling a mobile phone moving from the IMS mobile network to a SIP WLAN network without re-authentication. • Identity Federation between the Mobile and Fixed domain enabling the delivery of calls addressed to one domain at the other domain.</p>
122

Towards Modeling of Data in UML Activities with the SPACE Method : An Example-Driven Discussion

Heitmann, Nina January 2008 (has links)
<p>The focus of this work is the rapid engineering method SPACE, developed at NTNU. In this method, services are modeled using UML 2.0 collaborations and activities, and from these executable code can be generated. Services can be composed from other services and building blocks. Until recently, SPACE has only focused on control flow. We have extended SPACE by introducing data flow modeling into SPACE activities. This raises some important questions, for example, how data between building blocks may be shared. We discuss a number of possible solutions. Our work is driven by the UNO card game as an example application. The structure and behavior of the UNO card game is analyzed and discussed, highlighting and exemplifying the aspects discussed in this work.</p>
123

New distribution channels for advertising through computer games and mobile devices.

Sivagnanasuntharam, Sivasathees January 2008 (has links)
<p>The development in advertising industry has lately gone from open advertising through few, major distribution channels to a hidden and targeting advertising integrated into everyday life. Advertisers grow increasingly unhappy with the value delivered by the traditional mediums. They turn to alternative distribution channels in order to increase the success rate of advertising campaigns. Channels seen as unattractively with little purchasing power previously are attracting advertisers’ attention. The goal of this thesis has been to identify future distribution channels for advertising through computer games and mobile devices. In addition to identify, the report aims to look into the market potential of the identified advertising channels as well. This thesis begins with an introduction to advertising. Then advertising in computer games are investigated in the next chapter. The audience and business aspects of this advertising branch are examined and existing distribution channels are presented. Then a case study of advertising in a computer game named Cricket 07 and a virtual world called Second Life are carried out. Based on the thorough case study, several unexploited advertising channels are found and presented. The concepts are described in detail and high-level technical models are presented. The second part of the thesis examines mobile advertising. The same procedure is used here as for advertising in computer games. The main contribution of this part is the proposed solution presented in the end of the chapter. An advertising channel tailor made for Wireless Trondheim is described and a high-level technical model of the proposed distribution channel is given. The main contribution of this thesis is the identification of new distribution channels for advertising through computer games and mobile devices.</p>
124

Techno Economic Analysis of Interconnected Digital Home Networks

Tamvada, Jagannatha Haritash January 2008 (has links)
<p>A home network is a popular method of allowing computers to communicate with each other within a given residential area or a local area network. Homes are the new frontiers of technology in the current global scenario, a digital interconnected home network is a reality and an efficient means to exchange information seamlessly across different homes and across different geographies is the need of the hour. The interconnection of different homes is possible with the existing ADSL subscriptions but would need changes in the existing gateway structures, which could be challenging for the less techno-savvy. In an effort to make life easier for the end user and help making the interconnection between various home networks seamless, a small device called I-Box is introduced through this project, which is essentially a small UPnP device with rich features and functionalities. This thesis gives an overview of the I-Box technology and with the help of various popular theoretical frameworks and concepts, investigates available Marketing channels and suggests a suitable deployment strategy for the I-Box by making a comparative study of the various possible scenarios and thereby identifying the most suitable model for its deployment.</p>
125

Conceptualization and Design of a Context-Aware Platform for User-centric Applications

Hristova, Ana January 2008 (has links)
<p>With the appearance and expansion of mobile devices, ubiquitous computing is becoming more popular nowadays and the user and his tasks are becoming the focus of application development. One area of ubiquitous computing is composed by the context-aware systems, systems where applications are designed to react to the constant changes in the environment. The heterogeneity of the different domains where context is a key parameter has generated different approaches for context acquisition and modeling. Thus, a number of platforms have been developed in order to alleviate the process of application development and to set a common practice for building applications and services. This thesis studies the different platforms, focusing on the Context Toolkit. It examines the design principles, context representation, context acquiring methods and context handling. By developing services for a smart home, it explores the mechanisms applied in the framework and evaluates it. Furthermore, proposals for improving the Context Toolkit’s functionality and the application’s performance are given, by introducing the concept of quality of context and several enhancements regarding the resource discovery mechanism. Consequently, after gaining hands-on experience with developing a sample context-aware application and analyzing the Context Toolkit, a context-aware platform design is proposed which offers a complete solution defining all the necessary components and their interactions.</p>
126

A Demonstration on Service Compositions based on Natural Language Request and User Contexts

Sutthikulphanich, Kirati January 2008 (has links)
<p>The significant growth in mobile markets exposes business niches. A number of heterogeneous services have been offered to end users by several service providers. The end users can fully benefit from wide varieties of services only when these heterogeneous services can be composed together (i.e. service composition is created). This fact motivates an invention of frameworks that support diverse features such as service creations and compositions. The frameworks aid new market players to enter and offer innovative services. Such frameworks could benefit users by offering a big pool of services, and service providers by simplifying deployment process in adopting groundbreaking services. To achieve this, SPICE (Service Platform for Innovative Communication Envi-ronment) project has been established. In SPICE project, the researchers have developed, among other things, two environments: a Service Creation Environment (SCE) and a Service Execution Environment (SEE). An objective of SCE is to create and compose web services and Telecommunication services. An objective of SEE is to execute compositions of the services created by SCE. Main component developed in SCE is Automatic Composition Engine (ACE). ACE dynamically constructs service composition that satisfies a request of service developers. The request has to be constructed in a formal way. Therefore, the informal request such as natural language request (i.e. in English) needs to be transformed into a formal service com-position request before it is sent to the ACE. Thus, clients of ACE are only limited to service developers who have enough knowledge to construct the formal request. To bring SCE out to the market where end users do not possess much of technical knowledge, this thesis proposes a development of Intelligence Agent (IA) as a new component of SCE. IA construct service composition from an informal request in natural language by using Natural Language Processing (NLP) technique. A context handling feature has also been considered in this thesis. In SPICE project, the researches have developed Knowledge Management Framework (KMF) that supports context handling. This thesis demonstrates a possibility to integrate IA with KMF so as to improve SCE. As a result of this thesis, we have developed a prototype of IA. IA receives a request from end user in natural language (English), analyze the request, search and compose for service composition candidates that satisfy the request and deploy the candidates into an artificial language, SPATEL. We have also developed a module of IA that registers and subscribes for a user context published by a knowledge source in KMF framework. IA takes into account a context of user (e.g. user location, user authentication) when it selects services from the service repository. IA also ensures that the desired service composition will be deployed when certain condition on user context arises.</p>
127

Computer Assisted Language Learning towards 2010 : Mobile Learning, User generated Content and Convergence

Drabløs, Lars Are Holth January 2008 (has links)
<p>Many topics have been touched in this thesis. I would like to conclude with some answers to the questions raised in the initial problem description and point out further challenges in some cases. We have seen that there exist several approaches for CALL, with virtual learning communities as one example. The community presented here, moodle.org, is an open source framework and let any user register for free and manage a course. In that way may this framework be used by school institutions, professional language course providers and other users who feel free to organize a course. This environment is quite formal in nature, because most of the use at the portal is related to a registered course. Another portal, italki.com, offers language learning after the tandem method and users are free to search among all (visible) profiles on the sites to find a match. This is a more informal framework as the users are not connected to any established educational institution, they do not necessarily follow a curriculum and the learning is not instructed to follow any pedagogical principles. These portals may be accessed both in stationary and mobile environments (by mobile browsers). In the case of mobile environments there exist many challenges: Developers of the site are requested to take special considerations of how some material is to be structured to fit the interface at the user’s terminal. One of the considerations at moodle.org was for instance to limit graphical content (illustrated in chapter 5.2.1), as this takes up much space on the screen and uses quite a bit bandwidth to download. Other challenges can be related to media richness and context awareness discussed in chapter two. One example could for instance be a video conference lecture held at a moodle course. If some of the users are in a mobile environment without the possibility to transfer video (because of terminal or bandwidth limitation), they should still be given the option of following the lecture by audio transmission. This will reduce the richness of the lecture, but they will be able to catch up the most essential things. BBC offers another kind of framework which is typically meant for beginner learners in a language. The material in ‘Language steps’ is instructional and interactive, as it requires response and apprehension from the users. This makes it most suitable for stationary environments, but the content could be presented in a mobile environment to. The 3 “Rearranging the dialogue” task will probably be suitable for a touch screen handheld. The content in the different modules could also be categorized to fit the current response flexibility of the user. An example of different categories was given in chapter 2. Another framework presented from the BBC portal was their show “The Flatmates”. This is an internet based soap show where the episodes can be followed by downloadable tracks or simply be read. The users may contribute to the show with discussion about the characters and give feedback about how the show should continue. This is a good example of how the Internet can be used as a platform for participation among users. There also exist mobile applications like KODI’s dictionary and Coolgorilla’s audio phrase books. These can be categorized as referential tools and can be used in many settings, remarking that the audio phrase books in most cases are suited for beginners on vacation in the target language country. Chapter 6 discussed general possibilities and challenges related to technology and market trends. Web 2.0 was presented as the future trend of Internet usage and web design with key words as creativity, information sharing and collaboration between users (and companies). A survey, held by the Norwegian institute ITU has showed that Norwegian teenagers at average participate in 3,4 ‘network societies’. Facebook was the most popular. The biggest reason to participate in the networks was to meet friends. Only 8 percent answered that the networks provided help for school related topics. This shows that most of the interaction in these networks are informal among the teenagers. Could we still expect more participation in school related topics in such networks? The answer is yes, and no. The technology exists to promote school related subjects in these networks, but it would be a challenge to mix the pupils’ (and the teacher’s) roles in such a situation, as depicted in chapter 6.3. Hans Christian Arnseth also points out in [46] that the question about using more web 2.0 applications in the school system is much about ideology – “What do we regard as proper learning and how can/should technology be used in the education?”. At last were some general challenges related to technology presented, with issues around convergence, human aspects, business models and policy as the main issues. Copyright policy and business models can be even more complicated in the evolution of web 2.0 interfaces, where content sharing and user participation goes hand in hand.</p>
128

Representation of Human Behavior in Military Simulations

Engmo, Vidar January 2008 (has links)
<p>The purpose of this master thesis was to investigate the psychological and computational basis for human behavior representation (HBR) in military simulations and identify problem areas of existent software agent frameworks that provide computer generated forces (CGF) with human like cognitive abilities. The master thesis identifies psychological properties that influence human cognition in an operational environment through a theoretical study of operational and cognitive psychology. The psychological properties of human cognition are then connected to artificial intelligence through a theoretical study of agents and multi-agent systems and form the foundation for identifying general HBR properties. The HBR properties are used as evaluation markers that constitute the basis for constructing an evaluation of relevant agent frameworks thereby visualizing their strengths and weaknesses. The problem areas of incorporating artificial intelligence into CGF are further concretized by the development of a demonstrator that interacts with a synthetic environment. The demonstrator is an implementation of a tank platoon in the agent framework Jadex. The synthetic environment is provided by VR-Forces which is a product by MÄK technologies. The thesis makes a distinction between the conceptual structure of agent frameworks and their actual implementation. According to this master thesis it is the output of the agent framework that is the most important feature not how the output came into being. Producing the correct output requires the selection of the correct tools for the job. The selection of an agent framework should be taken on the background of an evaluation of the simulation requirements. A large portion of the development time is consumed by the development of application and communication interfaces. The problem is a result of lacking standardization and that most cognitive agent frameworks are experimental in nature. In addition the artificial intelligence (AI) in such simulations is often dived into levels, where the synthetic environment takes care of low-level AI and the agent framework the high-level AI. Tight synchronization between low and high-level AI is important if one wishes to create sensible behavior. The purpose of an agent framework in conjunction with CGF is thereby ensuring rapid development and testing of behavior models.</p>
129

Facebook in the Physical World

Moen, Sverre Sveum January 2008 (has links)
<p>This thesis investigates the idea of bringing an online social community into a public space. The concept is about building a bridge between an online social community and the physical world. We built a prototype public display to test the concept. The system was capable of displaying pictures of people who were standing in front of the system, pinpointing people’s hometowns on a map, and showing pictures that related to their interests. A one week test run of the system was carried out. We examined if this concept resulted people in getting to know each other better. The results support that this system led individuals to learn about each other.</p>
130

Fast Implementation of Two Hash Algorithms on nVidia CUDA GPU

Lerchundi Osa, Gorka January 2009 (has links)
<p>User needs increases as time passes. We started with computers like the size of a room where the perforated plaques did the same function as the current machine code object does and at present we are at a point where the number of processors within our graphic device unit it’s not enough for our requirements. A change in the evolution of computing is looming. We are in a transition where the sequential computation is losing ground on the benefit of the distributed. And not because of the birth of the new GPUs easily accessible this trend is novel but long before it was used for projects like SETI@Home, fightAIDS@Home, ClimatePrediction and there were shouting from the rooftops about what was to come. Grid computing was its formal name. Until now it was linked only to distributed systems over the network, but as this technology evolves it will take different meaning. nVidia with CUDA has been one of the first companies to make this kind of software package noteworthy. Instead of being a proof of concept it’s a real tool. Where the transition is expressed in greater magnitude in which the true artist is the programmer who uses it and achieves performance increases. As with many innovations, a community distributed worldwide has grown behind this software package and each one doing its bit. It is noteworthy that after CUDA release a lot of software developments grown like the cracking of the hitherto insurmountable WPA. With Sony-Toshiba-IBM (STI) alliance it could be said the same thing, it has a great community and great software (IBM is the company in charge of maintenance). Unlike nVidia is not as accessible as it is but IBM is powerful enough to enter home made supercomputing market. In this case, after IBM released the PS3 SDK, a notorious application was created using the benefits of parallel computing named Folding@Home. Its purpose is to, inter alia, find the cure for cancer. To sum up, this is only the beginning, and in this thesis is sized up the possibility of using this technology for accelerating cryptographic hash algorithms. BLUE MIDNIGHT WISH (The hash algorithm that is applied to the surgery) is undergone to an environment change adapting it to a parallel capable code for creating empirical measures that compare to the current sequential implementations. It will answer questions that nowadays haven’t been answered yet. BLUE MIDNIGHT WISH is a candidate hash function for the next NIST standard SHA-3, designed by professor Danilo Gligoroski from NTNU and Vlastimil Klima – an independent cryptographer from Czech Republic. So far, from speed point of view BLUE MIDNIGHT WISH is on the top of the charts (generally on the second place – right behind EDON-R - another hash function from professor Danilo Gligoroski). One part of the work on this thesis was to investigate is it possible to achieve faster speeds in processing of Blue Midnight Wish when the computations are distributed among the cores in a CUDA device card. My numerous experiments give a clear answer: NO. Although the answer is negative, it still has a significant scientific value. The point is that my work acknowledges viewpoints and standings of a part of the cryptographic community that is doubtful that the cryptographic primitives will benefit when executed in parallel in many cores in one CPU. Indeed, my experiments show that the communication costs between cores in CUDA outweigh by big margin the computational costs done inside one core (processor) unit.</p>

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