CONTREX: Design of embedded mixed-criticality CONTRol systems under consideration of EXtra-functional properties

The increasing processing power of today’s HW/SW platforms leads to the integration of more and more functions in a single device. Additional design challenges arise when these functions share computing resources and belong to different criticality levels. CONTREX complements current activities in the area of predictable computing platforms and segregation mechanisms with techniques to consider the extra-functional properties, i.e., timing constraints, power, and temperature. CONTREX enables energy efficient and cost aware design through analysis and optimization of these properties with regard to application demands at different criticality levels. This article presents an overview of the CONTREX European project, its main innovative technology (extension of a model based design approach, functional and extra-functional analysis with executable models and run-time management) and the final results of three industrial use-cases from different domain (avionics, automotive and telecommunication).The work leading to these results has received funding from the European Community’s Seventh Framework Programme FP7/2007-2011 under grant agreement no. 611146

IP and ATM integration: A New paradigm in multi-service internetworking

ATM is a widespread technology adopted by many to support advanced data communication, in particular efficient Internet services provision. The expected challenges of multimedia communication together with the increasing massive utilization of IP-based applications urgently require redesign of networking solutions in terms of both new functionalities and enhanced performance. However, the networking context is affected by so many changes, and to some extent chaotic growth, that any approach based on a structured and complex top-down architecture is unlikely to be applicable. Instead, an approach based on finding out the best match between realistic service requirements and the pragmatic, intelligent use of technical opportunities made available by the product market seems more appropriate. By following this approach, innovations and improvements can be introduced at different times, not necessarily complying with each other according to a coherent overall design. With the aim of pursuing feasible innovations in the different networking aspects, we look at both IP and ATM internetworking in order to investigating a few of the most crucial topics/ issues related to the IP and ATM integration perspective. This research would also address various means of internetworking the Internet Protocol (IP) and Asynchronous Transfer Mode (ATM) with an objective of identifying the best possible means of delivering Quality of Service (QoS) requirements for multi-service applications, exploiting the meritorious features that IP and ATM have to offer. Although IP and ATM often have been viewed as competitors, their complementary strengths and limitations from a natural alliance that combines the best aspects of both the technologies. For instance, one limitation of ATM networks has been the relatively large gap between the speed of the network paths and the control operations needed to configure those data paths to meet changing user needs. IP\u27s greatest strength, on the other hand, is the inherent flexibility and its capacity to adapt rapidly to changing conditions. These complementary strengths and limitations make it natural to combine IP with ATM to obtain the best that each has to offer. Over time many models and architectures have evolved for IP/ATM internetworking and they have impacted the fundamental thinking in internetworking IP and ATM. These technologies, architectures, models and implementations will be reviewed in greater detail in addressing possible issues in integrating these architectures s in a multi-service, enterprise network. The objective being to make recommendations as to the best means of interworking the two in exploiting the salient features of one another to provide a faster, reliable, scalable, robust, QoS aware network in the most economical manner. How IP will be carried over ATM when a commercial worldwide ATM network is deployed is not addressed and the details of such a network still remain in a state of flux to specify anything concrete. Our research findings culminated with a strong recommendation that the best model to adopt, in light of the impending integrated service requirements of future multi-service environments, is an ATM core with IP at the edges to realize the best of both technologies in delivering QoS guarantees in a seamless manner to any node in the enterprise

Resource Allocation and Service Management in Next Generation 5G Wireless Networks

The accelerated evolution towards next generation networks is expected to dramatically increase mobile data traffic, posing challenging requirements for future radio cellular communications. User connections are multiplying, whilst data hungry content is dominating wireless services putting significant pressure on network's available spectrum. Ensuring energy-efficient and low latency transmissions, while maintaining advanced Quality of Service (QoS) and high standards of user experience are of profound importance in order to address diversifying user prerequisites and ensure superior and sustainable network performance. At the same time, the rise of 5G networks and the Internet of Things (IoT) evolution is transforming wireless infrastructure towards enhanced heterogeneity, multi-tier architectures and standards, as well as new disruptive telecommunication technologies. The above developments require a rethinking of how wireless networks are designed and operate, in conjunction with the need to understand more holistically how users interact with the network and with each other. In this dissertation, we tackle the problem of efficient resource allocation and service management in various network topologies under a user-centric approach. In the direction of ad-hoc and self-organizing networks where the decision making process lies at the user level, we develop a novel and generic enough framework capable of solving a wide array of problems with regards to resource distribution in an adaptable and multi-disciplinary manner. Aiming at maximizing user satisfaction and also achieve high performance - low power resource utilization, the theory of network utility maximization is adopted, with the examined problems being formulated as non-cooperative games. The considered games are solved via the principles of Game Theory and Optimization, while iterative and low complexity algorithms establish their convergence to steady operational outcomes, i.e., Nash Equilibrium points. This thesis consists a meaningful contribution to the current state of the art research in the field of wireless network optimization, by allowing users to control multiple degrees of freedom with regards to their transmission, considering mobile customers and their strategies as the key elements for the amelioration of network's performance, while also adopting novel technologies in the resource management problems. First, multi-variable resource allocation problems are studied for multi-tier architectures with the use of femtocells, addressing the topic of efficient power and/or rate control, while also the topic is examined in Visible Light Communication (VLC) networks under various access technologies. Next, the problem of customized resource pricing is considered as a separate and bounded resource to be optimized under distinct scenarios, which expresses users' willingness to pay instead of being commonly implemented by a central administrator in the form of penalties. The investigation is further expanded by examining the case of service provider selection in competitive telecommunication markets which aim to increase their market share by applying different pricing policies, while the users model the selection process by behaving as learning automata under a Machine Learning framework. Additionally, the problem of resource allocation is examined for heterogeneous services where users are enabled to dynamically pick the modules needed for their transmission based on their preferences, via the concept of Service Bundling. Moreover, in this thesis we examine the correlation of users' energy requirements with their transmission needs, by allowing the adaptive energy harvesting to reflect the consumed power in the subsequent information transmission in Wireless Powered Communication Networks (WPCNs). Furthermore, in this thesis a fresh perspective with respect to resource allocation is provided assuming real life conditions, by modeling user behavior under Prospect Theory. Subjectivity in decisions of users is introduced in situations of high uncertainty in a more pragmatic manner compared to the literature, where they behave as blind utility maximizers. In addition, network spectrum is considered as a fragile resource which might collapse if over-exploited under the principles of the Tragedy of the Commons, allowing hence users to sense risk and redefine their strategies accordingly. The above framework is applied in different cases where users have to select between a safe and a common pool of resources (CPR) i.e., licensed and unlicensed bands, different access technologies, etc., while also the impact of pricing in protecting resource fragility is studied. Additionally, the above resource allocation problems are expanded in Public Safety Networks (PSNs) assisted by Unmanned Aerial Vehicles (UAVs), while also aspects related to network security against malign user behaviors are examined. Finally, all the above problems are thoroughly evaluated and tested via a series of arithmetic simulations with regards to the main characteristics of their operation, as well as against other approaches from the literature. In each case, important performance gains are identified with respect to the overall energy savings and increased spectrum utilization, while also the advantages of the proposed framework are mirrored in the improvement of the satisfaction and the superior Quality of Service of each user within the network. Lastly, the flexibility and scalability of this work allow for interesting applications in other domains related to resource allocation in wireless networks and beyond

Software test and evaluation study phase I and II : survey and analysis

Issued as Final report, Project no. G-36-661 (continues G-36-636; includes A-2568

A critical analysis of contemporary early childhood policies: The experience of the ‘Cuna Mas’ National Programme

This thesis is concerned with exploring why and how early childhood development becomes an object of policy. More specifically, it sets out to explore the couplings of knowledge and power and how these productive encounters materialize in discourses, practices and subjectivities that create the conditions for the governing of children and parents. A Foucauldian theoretical framework informed by postcolonial ideas is drawn on to question dominant understandings about young children, their development and the related production of policy knowledge. Based on a documentary analysis of policy texts of two multilateral organizations, it argues that specific evidence and research are used to construct early childhood development as foundational, malleable and profitable, and to prescribe a particular version of the ‘normal’ child and the ‘good’ parent. At the same time, it describes how data and statistics are strategically deployed to demonstrate the existence of a ‘problem’, which works to position less privileged children and their families as ‘delayed’, ‘unable’, and in ‘need’. An investment narrative is identified as providing an economic rationale for government intervention in early childhood development that reinforces an understanding of children as potential human capital. Drawing on Ball’s methodological and analytical ‘toolbox’, the thesis traces how global narratives are reproduced, interpreted and refused at a particular national setting, while at the same time offering an insider’s perspective of how policies are shaped, produced, enacted, and, importantly, with what effects. A critical auto-ethnography is used to reconstruct and examine the different contexts of influence, policy text production, practice and outcomes. The thesis examines these contexts in a particular site of policy experience: the national programme ‘Cuna Mas’ in Peru. It considers the effects of globalisation and the role of context and agency in forming, framing and limiting the production and enactment of state national policies, arguing that despite being informed by the globalised policy discourses, there is evidence of active adaptation and recontextualisation by local staff

User Experience of Geocaching and Its Application to Tourism and Education

Advances in technology have provided new ways of using entertainment and game technology to foster human interaction. Games and playing with games have always been an important part of people’s everyday lives. Traditionally, human-computer interaction (HCI) research was seen as a psychological cognitive science focused on human factors, with engineering sciences as the computer science part of it. Although cognitive science has made significant progress over the past decade, the influence of people’s emotions on design networks is increasingly important, especially when the primary goal is to challenge and entertain users (Norman 2002). Game developers have explored the key issues in game design and identified that the driving force in the success of games is user experience. User-centered design integrates knowledge of users’ activity practices, needs, and preferences into the design process. Geocaching is a location-based treasure hunt game created by a community of players. Players use GPS (Global Position System) technology to find “treasures” and create their own geocaches; the game can be developed when the players invent caches and used more imagination to creations the caches. This doctoral dissertation explores user experience of geocaching and its applications in tourism and education. Globally, based on the Geocaching.com webpage, geocaching has been played about 180 countries and there are more than 10 million registered geocachers worldwide (Geocaching.com, 25.11.2014). This dissertation develops and presents an interaction model called the GameFlow Experience model that can be used to support the design of treasure hunt applications in tourism and education contexts. The GameFlow Model presents and clarifies various experiences; it provides such experiences in a real-life context, offers desirable design targets to be utilized in service design, and offers a perspective to consider when evaluating the success of adventure game concepts. User-centered game designs have adapted to human factor research in mainstream computing science. For many years, the user-centered design approach has been the most important research field in software development. Research has been focusing on user-centered design in software development such as office programs, but the same ideas and theories that will reflect the needs of a user-centered research are now also being applied to game design (Charles et al. 2005.) For several years, we have seen a growing interest in user experience design. Digital games are experience providers, and game developers need tools to better understand the user experience related to products and services they have created. This thesis aims to present what the user experience is in geocaching and treasure hunt games and how it can be used to develop new concepts for the treasure hunt. Engineers, designers, and researchers should have a clear understanding of what user experience is, what its parts are, and most importantly, how we can influence user satisfaction. In addition, we need to understand how users interact with electronic products and people, and how different elements synergize their experiences. This doctoral dissertation represents pioneering work on the user experience of geocaching and treasure hunt games in the context of tourism and education. The research also provides a model for game developers who are planning treasure hunt concepts.Teknologinen kehitys on tarjonnut uusia tapoja hyödyntää viihdettä ja peliteknologiaa ihmisten välisessä vuorovaikutuksessa. Pelit ja niiden pelaaminen on ollut aina tärkeä osa ihmisten arkipäivää. Ihmisen ja tietokoneen välisen vuorovaikutuksen tutkimus, human-computer interaction research (HCI), on perinteisesti nähty kognitiivisena psykologiana, johon kuuluvat inhimilliset tekijät, sekä insinööritieteenä, johon sisältyy tietojenkäsittelytiede. Vaikka kognitiivinen tiede on kehittynyt viime vuosina valtavasti, suunnitteluverkostoihin vaikuttavat ihmisten tunteet ovat yhä tärkeämmässä osassa, erityisesti silloin kun tavoitteena on haastaa ja viihdyttää käyttäjiä. (Norman 2002.) Pelinkehittäjät ovat selvittäneet pelisuunnittelun kannalta olennaisia tekijöitä ja tunnistaneet, että pelien menestyksen salaisuus on käyttäjäkokemus. Käyttäjäkeskeisessä suunnittelussa käyttäjien toiminnan käytäntöjen, tarpeiden ja toiveiden tuntemus tuodaan mukaan suunnitteluprosessiin. Geokätköily on paikannukseen perustuva aarteenetsintäpeli, jonka pelaajat ovat luoneet yhdessä. Pelaajat käyttävät GPS-teknologiaa "aarteiden" etsimiseen ja lisäävät omia geokätkökohteita ja peli kehittyy jatkuvasti pelaajien keksiessä kätköjä, jotka vaativat yhä enemmän mielikuvitusta. Tässäväitöskirjassa tutkitaan geokätköilyn käyttäjäkokemusta ja sen sovelluksia koulutuksen- ja matkailunaloilla. Perustuen Geocaching.com websivustoon geokätköilyä pelataan noin 180 maassa, ja rekisteröityneitä käyttäjiä on yli kymmenen miljoonaa eri puolilla maailmaa (Geocaching.com, 25.11.2014). Tässä tutkielmassa esitellään vuorovaikutusmalli nimeltään GameFlow Experience -mallia, jota voidaan käyttää aarteenetsintäsovellusten suunnittelussa koulutuksen- ja matkailualojen konteksteissa. GameFlow Experience -malli esittelee ja selventää erilaisia kokemuksia - se esittelee ne todellisessa kontekstissa, tarjoaa erilaisia suunnittelutavoitteita palvelusuunnittelua varten sekä näkökulman, joka tulisi ottaa huomioon seikkailupelien menestystä arvioitaessa. Käyttäjäkeskeisessä pelisuunnittelussa on sovellettu inhimillisten tekijöiden tutkimusta valtavirran tietojenkäsittelytieteeseen. Useiden vuosien ajan, käyttäjäkeskeisen suunnittelun lähestymistavasta on tullut tärkein tutkimusala ohjelmistokehityksessä. Tutkimus on keskittynyt ohjelmistojen kehitykseen käyttäjäkeskeisessä suunnittelussa etenkin toimisto-ohjelmistoihin, mutta samoja ideoita ja teorioita, jotka heijastavat yhteiskunnan tarpeita käyttäjäkeskeisessä tutkimuksessa sovelletaan nyt myös pelisuunnitteluun. (Charles ja ym. 2005.) Kiinnostus käyttäjäkokemuksen suunnitteluun on kasvanut jo useiden vuosien ajan. Digitaaliset pelit tarjoavat kokemuksia, ja pelisuunnittelijat tarvitsevatkin työkaluja, joiden avulla voidaan entistä paremmin ymmärtää tuotteiden ja palvelujen luomia käyttäjäkokemuksia. Tutkimuksen tavoitteena on esitellä käyttäjäkokemusta ja miten sitä voidaan käyttää uusien aarteenmetsästyskonseptien kehittämiseen. Insinööreillä, suunnittelijoilla ja tutkijoilla tulisi olla selkeä käsitys siitä, mikä käyttäjäkokemus on, mitkä ovat sen osat ja mikä tärkeintä, miten voimme vaikuttaa käyttäjän tyytyväisyyteen. Lisäksi pitäisi ymmärtää, miten käyttäjät toimivat elektronisten tuotteiden kanssa sekä miten ihmiset toimivat vuorovaikutuksessa toistensa kanssa ja miten eri osat vaikuttavat yhdessä käyttäjien kokemuksiin. Väitöskirja on pioneerityö käyttäjäkokemuksesta geokätköilyssä ja aarteenetsintä peleissä matkailun ja opetuksen kontekstissa. Tutkimus antaa myös mallin pelin kehittäjille, jotka suunnittelevat aarteenetsintäkonsepteja.Siirretty Doriast

Application priority framework for fixed mobile converged communication networks

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.The current prospects in wired and wireless access networks, it is becoming increasingly important to address potential convergence in order to offer integrated broadband services. These systems will need to offer higher data transmission capacities and long battery life, which is the catalyst for an everincreasing variety of air interface technologies targeting local area to wide area connectivity. Current integrated industrial networks do not offer application aware context delivery and enhanced services for optimised networks. Application aware services provide value-added functionality to business applications by capturing, integrating, and consolidating intelligence about users and their endpoint devices from various points in the network. This thesis mainly intends to resolve the issues related to ubiquitous application aware service, fair allocation of radio access, reduced energy consumption and improved capacity. A technique that measures and evaluates the data rate demand to reduce application response time and queuing delay for multi radio interfaces is proposed. The technique overcomes the challenges of network integration, requiring no user intervention, saving battery life and selecting the radio access connection for the application requested by the end user. This study is split in two parts. The first contribution identifies some constraints of the services towards the application layer in terms of e.g. data rate and signal strength. The objectives are achieved by application controlled handover (ACH) mechanism in order to maintain acceptable data rate for real-time application services. It also looks into the impact of the radio link on the application and identifies elements and parameters like wireless link quality and handover that will influence the application type. It also identifies some enhanced traditional mechanisms such as distance controlled multihop and mesh topology required in order to support energy efficient multimedia applications. The second contribution unfolds an intelligent application priority assignment mechanism (IAPAM) for medical applications using wireless sensor networks. IAPAM proposes and evaluates a technique based on prioritising multiple virtual queues for the critical nature of medical data to improve instant transmission. Various mobility patterns (directed, controlled and random waypoint) has been investigated and compared by simulating IAPAM enabled mobile BWSN. The following topics have been studied, modelled, simulated and discussed in this thesis: 1. Application Controlled Handover (ACH) for multi radios over fibre 2. Power Controlled Scheme for mesh multi radios over fibre using ACH 3. IAPAM for Biomedical Wireless Sensor Networks (BWSN) and impact of mobility over IAPAM enabled BWSN. Extensive simulation studies are performed to analyze and to evaluate the proposed techniques. Simulation results demonstrate significant improvements in multi radios over fibre performance in terms of application response delay and power consumption by upto 75% and 15 % respectively, reduction in traffic loss by upto 53% and reduction in delay for real time application by more than 25% in some cases

The Role of Logistics Service Quality in Creating Customer Loyalty

The purpose of this dissertation is to examine the loyalty phenomenon and to understand the role of logistics service in creating customer loyalty. The main objective is to help companies assess the impact of logistics service in creating loyalty. Logistics service quality is purported to consist of two separate constructs – relational LSQ and operational LSQ. These elements of LSQ drive satisfaction. This research also explores the loyalty phenomenon, which is conceptualized as a causal relationship between affective commitment and purchasing behavior. The strength of this relationship is proposed to be moderated by calculative commitment, which involves the calculation of costs and benefits and the assessment of the investments made in the relationship, along with the availability of alternatives. Further, satisfaction influences the loyalty relationship differently. This research contends that satisfaction has a linear relationship to affective commitment, but its relationship to purchase behavior is nonlinear, being more significant at the extremes. These constructs are defined and operationalized, and by testing its components, along with calculative commitment and satisfaction, different loyalty types should be identified. Understanding that firms have a portfolio of different customer relationships, the research should ascertain what conditions drive various types of customer relationships. This nomological model should also provide managerial insight to the proposition that there are different loyalty types that would have different strategic implications. Top firms recognize the differences in the needs and desires of major customers and design offerings according to those needs (Zhao, Droge and Stank 1996). Because an important goal for firms is to grow a larger share of the profitable revenue available (Bowersox, Closs and Stank 2000), managers must realize that not all customers are the same. This research should help distinguish different customer segments based on their loyalty profiles. If the loyalty relationship can be better understood, then managers will have more clarity about how to determine what level of logistics service (as well as other services) to provide to different customer groups

Reliability and Efficiency of Vehicular Network Applications

The DSRC/WAVE initiative is forecast to enable a plethora of applications, classified in two broad types of safety and non-safety applications. In the former type, the reliability performance is of tremendous prominence while, in the latter case, the efficiency of information dissemination is the key driving factor. For safety applications, we adopt a systematic approach to analytically investigate the reliability of the communication system in a symbiotic relationship with the host system comprising a vehicular traffic system and radio propagation environment. To this aim, the¬ interference factor is identified as the central element of the symbiotic relationship. Our approach to the investigation of interference and its impacts on the communication reliability departs from previous studies by the degree of realism incorporated in the host system model. In one dimension, realistic traffic models are developed to describe the vehicular traffic behaviour. In a second dimension, a realistic radio propagation model is employed to capture the unique signal propagation aspects of the host system. We address the case of non-safety applications by proposing a generic framework as a capstone architecture for the development of new applications and the efficiency evaluation of existing ones. This framework, while being independent from networking technology, enables accurate characterization of the various information dissemination tasks that a node performs in cooperation with others. As the central element of the framework, we propose a game theoretic model to describe the interaction of meeting nodes aiming to exchange information of mutual or social interests. An adaptive mechanism is designed to enable a mobile node to measure the social significance of various information topics, which is then used by the node to prioritize the forwarding of information objects