Discrete and Continuous Optimization Methods for Self-Organization in Small Cell Networks - Models and Algorithms

Self-organization is discussed in terms of distributed computational methods and algorithms for resource allocation in cellular networks. In order to develop algorithms for different self-organization problems pertinent to small cell networks (SCN), a number of concepts from discrete and continuous optimization theory are employed. Self-organized resource allocation problems such as physical cell identifier (PCI) assignment and primary component carrier selection are formulated as discrete optimization problems. Distributed graph coloring and constraint satisfaction algorithms are used to solve these problems. The PCI assignment is also discussed for multi-operator heterogeneous networks. Furthermore, different variants of simulated annealing are proposed for solving a graph coloring formulation of the orthogonal resource allocation problem. In the continuous optimization domain, a network utility maximization approach is considered for solving different resource allocation problems. Network synchronization is addressed using greedy and gradient search algorithms. Primal and dual decomposition are discussed for transmit power and scheduling weight optimizations, under a network-wide power constraint. Joint optimization over transmit powers and multi-user scheduling weights is considered in a multi-carrier SCN, for both maximum rate and proportional-fair rate utilities. This formulation is extended for multiple-input multiple-output (MIMO) SCNs, where apart from transmit powers and multi-user scheduling weights, the transmit precoders are also optimized, for a generic alpha-fair utility function. Optimization of network resources over multiple degrees of freedom is particularly effective in reducing mutual interference, leading to significant gains in network utility. Finally, an alternate formulation of transmit power allocation is considered, in which the network transmit power is minimized subject to the data rate constraints of users. Thus, network resource allocation algorithms inspired by optimization theory constitute an effective approach for self-organization in contemporary as well as future cellular networks

Semantic discovery and reuse of business process patterns

Patterns currently play an important role in modern information systems (IS) development and their use has mainly been restricted to the design and implementation phases of the development lifecycle. Given the increasing significance of business modelling in IS development, patterns have the potential of providing a viable solution for promoting reusability of recurrent generalized models in the very early stages of development. As a statement of research-in-progress this paper focuses on business process patterns and proposes an initial methodological framework for the discovery and reuse of business process patterns within the IS development lifecycle. The framework borrows ideas from the domain engineering literature and proposes the use of semantics to drive both the discovery of patterns as well as their reuse

Building capacity in climate change policy analysis and negotiation: methods and technologies

Capacity building is often cited as the reason “we cannot just pour money into developing countries” and why so many development projects fail because their design does not address local conditions. It is therefore a key technical and political concept in international development. Some of the poorest countries in the world are also some of the most vulnerable to the impacts of climate change. Their vulnerability is in part due to a lack of capacity to plan and anticipate the effects of climate change on crops, water resources, urban electricity demand etc. What capacities do these countries lack to deal with climate change? How will they cope? What steps can they take to reduce their vulnerability? This innovative and high-profile research project was part of a larger project (called C3D) and conducted with non-governmental organisations in Senegal, South Africa and Sri Lanka. The research involved several participatory workshops and a questionnaire to all three research centres

The Theory and Practice of Online Learning

Every chapter in the widely distributed first edition has been updated, and four new chapters on current issues such as connectivism and social software innovations have been added. Essays by practitioners and scholars active in the complex, diverse, and rapidly evolving field of distance education blend scholarship and research; practical attention to the details of teaching and learning; and mindful attention to the economics of the business of education

Collaborative Working Environments : Group Needs Approach to Designing Systems for Supporting Spatially Distributed Groups

Collaboration in spatially distributed groups requires technological support for mediating collaborative activities and members’ interactions over time and distance. Technology provides multiple tools for supporting individual, social and task requirements of collaborative groups. Nevertheless, many aspects of computer-mediated interactions are not sufficiently explained and creating an effective computer-supported environment for collaborative groups as a combination of these tools remains a challenge. Meeting this challenge requires taking into consideration different aspects of collaborative interactions from both social and technological perspectives. This thesis discusses the social and technical aspects of collaboration in spatially distributed groups and introduces a design approach for collaborative working environments. Firstly, it presents a comprehensive overview of research on collaborative groups, summarizing three interrelated elements under the umbrella of the group needs approach: individual, task and group maintenance needs. Secondly, it proposes a design approach for collaborative working environments on the basis of group needs and thus presents an alternative for designing computer-supported environment for collaborative groups. This research considers two main types of systems for supporting collaborative groups – groupware and social software – and discusses functionalities originating from these systems. It introduces the Quality Function Deployment method and utilizes its House of Quality concept in order to develop and initially evaluate the First-Stage Prototype – the prototypical implementation of the collaborative working environment combining these two main types. The presented framework is used as a benchmarking tool on the basis of which selected existing platforms for supporting collaboration are evaluated. This research contributes to the area of the Computer-Supported Cooperative Work and discusses actual trends in development of collaborative systems related to the application of new social tools for purposes of computer-supported collaboration.Kollaborative Arbeitsumgebungen – der Gruppenbedürfnisansatz zur Entwicklung von Systemen für die Unterstützung räumlich verteilter Gruppen Die Zusammenarbeit in räumlich verteilten Gruppen erfordert technologische Unterstützung um Interaktionen innerhalb der Gruppen über Zeit und Distanz zu ermöglichen. Dabei bieten heutige Technologien verschiedene Tools zur Unterstützung von individuellen, sozialen und aufgabenorientierten Anforderungen der Gruppen. Allerdings sind viele Aspekte von computervermittelten Interaktionen nicht ausreichend erforscht und die Gestaltung von effektiven computerunterstützten Umgebungen für zusammenarbeitende Gruppen als eine Kombination dieser Tools bleibt eine Herausforderung. Die Erfüllung dieser Anforderungen erfordert die Berücksichtigung unterschiedlicher Aspekte der Gruppeninteraktionen sowohl aus sozialer als auch aus technologischer Perspektive. Die vorliegende Arbeit untersucht die sozialen und technischen Aspekte der Zusammenarbeit in räumlich verteilten Gruppen und präsentiert einen Entwicklungsansatz für Systeme zur Unterstützung der Zusammenarbeit. Zum einen gibt sie einen umfassenden Überblick über den aktuellen Forschungsstand zum Thema kooperative Gruppen und fasst dabei die drei verbundenen Elemente individuelle Bedürfnisse, Aufgabenbedürfnisse und Bedürfnisse zur Aufrechterhaltung der Gruppen unter dem Dach des Gruppenbedürfnisansatzes zusammen. Zum anderen präsentiert die Arbeit ein Entwicklungskonzept für kooperative Arbeitsumgebungen auf Grundlage dieses Ansatzes und somit eine Alternative für die Gestaltung von computerunterstützten Umgebungen für kollaborative Gruppen. Für diese Forschungsarbeit werden im Wesentlichen zwei Arten von Systemen sowie deren Funktionalitäten zur Unterstützung von kollaborativen Gruppen diskutiert – Groupware und Social Software. Um eine prototypische Implementierung einer kollaborativen Arbeitsumgebung zu entwickeln und eine erste Evaluation durchzuführen, wird die Quality Function Deployment Methode und das damit verbundene House of Quality Konzept verwendet. Die Forschungsergebnisse leisten einen Beitrag auf dem Gebiet der computerunterstützten Gruppenarbeit (Computer-Supported Cooperative Work) und diskutieren aktuelle Trends im Bereich der Entwicklung kollaborativer Arbeitsumgebungen, die sich mit der Integration von neuen sozialen Tools zum Zweck computerunterstützter Zusammenarbeit beschäftigen

Developing sustainable business models for institutions’ provision of open educational resources: Learning from OpenLearn users’ motivations and experiences

Universities across the globe have, for some time, been exploring the possibilities for achieving public benefit and generating business and visibility through releasing and sharing open educational resources (OER). Many have written about the need to develop sustainable and profitable business models around the production and release of OER. Downes (2006), for example, has questioned the financial sustainability of OER production at scale. Many of the proposed business models focus on OER’s value in generating revenue and detractors of OER have questioned whether they are in competition with formal education. This paper reports on a study intended to broaden the conversation about OER business models to consider the motivations and experiences of OER users as the basis for making a better informed decision about whether OER and formal learning are competitive or complementary with each other. The study focused on OpenLearn - the Open University’s (OU) web-based platform for OER, which hosts hundreds of online courses and videos and is accessed by over 3,000,000 users a year. A large scale survey and follow-up interviews with OpenLearn users worldwide revealed that university provided OER can offer learners a bridge to formal education, allowing them to try out a subject before registering on a formal course and to build confidence in their abilities as learners. In addition, it was found that using OER during formal paid-for study can improve learners’ performance and self-reliance, leading to increased retention and satisfaction with the learning experience

International Perspectives of Distance Learning in Higher Education

This book, written by authors representing 12 countries and five continents, is a collection of international perspectives on distance learning and distance learning implementations in higher education. The perspectives are presented in the form of practical case studies of distance learning implementations, research studies on teaching and learning in distance learning environments, and conceptual and theoretical frameworks for designing and developing distance learning tools, courses and programs. The book will appeal to distance learning practitioners, researchers, and higher education administrators. To address the different needs and interests of audience members, the book is organized into five sections: Distance Education Management, Distance Education and Teacher Development, Distance Learning Pedagogy, Distance Learning Students, and Distance Learning Educational Tools