Fatos Xhafa - Academia.edu (original) (raw)

Papers by Fatos Xhafa

Drexel E-Repository and Archive (iDEA) http://idea.library.drexel.edu/ ... Drexel University Libr... more Drexel E-Repository and Archive (iDEA) http://idea.library.drexel.edu/ ... Drexel University Libraries www.library.drexel.edu ... The following item is made available as a courtesy to scholars by the author(s) and Drexel University Library and may contain materials and content, including ...

Studies in Computational Intelligence, 2013

ABSTRACT Discusses the theories, practices and concepts of utilising inter-operable and inter-coo... more ABSTRACT Discusses the theories, practices and concepts of utilising inter-operable and inter-cooperative next generation computational technologies Includes mobile and the emerging e-infrastructures of Web 2.0, SOA, P2P, Grids and Clouds Written by leading experts in the field Over the past two decades, we have witnessed unprecedented innovations in the development of miniaturized electromechanical devices and low-power wireless communication making practical the embedding of networked computational devices into a rapidly widening range of material entities. This trend has enabled the coupling of physical objects and digital information into cyber-physical systems and it is widely expected to revolutionize the way resource computational consumption and provision will occur. Specifically, one of the core ingredients of this vision, the so-called Internet of Things (IoT), demands the provision of networked services to support interaction between conventional IT systems with both physical and artificial objects. In this way, IoT is seen as a combination of several emerging technologies, which enables the transformation of everyday objects into smart objects. It is also perceived as a paradigm that connects real world with digital world. The focus of this book is on the novel collective and computational intelligence technologies that will be required to achieve this goal. While, one of the aims of this book is to discuss the progress made, it also prompts future directions on the utilization of inter-operable and cooperative next generation computational technologies, which supports the IoT approach, that being an advanced functioning towards an integrated collective intelligence approach for the benefit of various organizational settings. Content Level » Research Keywords » Computational Intelligence - Grids and Clouds - Internet of Things - Next Generation Computational Technologies - P2P - SOA - Web 2.0 Related subjects » Artificial Intelligence - Computational Intelligence and Complexity - Information Systems and Applications

International Journal of Space-Based and Situated Computing, 2013

Pressures on the availability of healthcare spaces, the high costs of institutional care, and the... more Pressures on the availability of healthcare spaces, the high costs of institutional care, and the desires of those being cared for, cause a current move toward care either at home or within low-supervision environments. This brings about an important question: how can smart care spaces be created that intelligently link the home care environment to the needs of the cared-for? To a significant degree this involves development of sensored spaces connected to intelligent computer-systems. However, that intelligence requires an understanding of how sensors can provide more than just environmental variables, instead making systems aware of symptoms, comfort and potential needs for intervention. Therefore, this paper discusses the current need for development of smart care spaces, provides an introduction to some of the cost-effective sensors available, and reviews links between sensor data and medical conditions. of home care, where the cared-for can benefit from that monitoring in a familiar and dignity-preserving environment.

International Journal of Ad Hoc and Ubiquitous Computing, 2014

Society is experiencing an ageing demographic, coupled with increasingly prevalent Alzheimer and ... more Society is experiencing an ageing demographic, coupled with increasingly prevalent Alzheimer and Dementia conditions, expected to cause explosive increases in healthcare costs. There is a need to develop pervasive technologies that allow monitoring of patients at home, where medically permissible, to reduce pressures on formal healthcare spaces. Those 'smart care spaces' require use of sensors and intelligent computer systems to support the needs of the cared-for, carers and medical personnel. In so doing they can ensure quality-of-life through comfort and adequate medical-monitoring, as well as providing significant data for ongoing medical evaluation and diagnosis. This requires two main elements of sensing: sensors to monitor the care environment and patient-mounted sensors to monitor physiological parameters. Therefore, this paper considers technological options available for such monitoring and provides examples of their use. It will be concluded that cost-effective solutions are available for development of smart care space monitoring.

Invention consists in avoiding the constructing of useless contraptions and in constructing the u... more Invention consists in avoiding the constructing of useless contraptions and in constructing the useful combinations which are in infinite minority."

Cluster formation and cluster head selection are important problems in sensor network application... more Cluster formation and cluster head selection are important problems in sensor network applications and can drastically affect the network's communication energy dissipation. However, selecting of the cluster head is not easy in different environments which may have different characteristics. In our previous work, in order to deal with this problem, we proposed a power reduction algorithm for sensor networks based

Mesh router nodes placement is a central problem in Wireless Mesh Networks (WMNs). An efficient p... more Mesh router nodes placement is a central problem in Wireless Mesh Networks (WMNs). An efficient placement of mesh router nodes is indispensable for achieving network performance in terms of both network connectivity and user coverage. Unfortunately the ...

The durability of Wireless Sensor Networks (WSNs) is a major issue that impacts the application o... more The durability of Wireless Sensor Networks (WSNs) is a major issue that impacts the application of such networks. While communication protocols are striving to save energy by acting on sensor nodes, recent results show that network lifetime can be extended by further involving sink mobility. As most proposals give their evidence of lifetime improvement through numerical simulations and field tests, a study which combines the sink mobility with the different existing routing protocols is still missing. In this work, we investigate how sensor networks perform when the sink node is mobile. We compare the simulation results for two cases: when the sink node is stationary and mobile, considering lattice and random topologies and using three routing protocols: AODV, DSDV, and DSR. The simulation results have shown that for the case of mobile sink, the depleted energy is half than what was consumed in the case of motionless sink. As well, the consumed energy of lattice topology is 4% to 9% low if compared to that of random topology. Finally, DSDV seems to have the best performance in terms of depleted energy (16% and 6%, of the total energy for stationary and mobile sink, respectively), yet it has the poorest packet delivery ratio (100% to 76,23%, for motionless and itinerant sink, respectively).

ABSTRACT We present a C++ implementation of a skeleton for Tabu Search method. Tabu Search method... more ABSTRACT We present a C++ implementation of a skeleton for Tabu Search method. Tabu Search method is a well-known meta-heuristic that has proved successful for suboptimally solving hard combinatorial optimization problems. This method has been already implemented for a large number of optimization problems, to the best of our knowledge they are all ad hoc implementations. We propose a generic C++ implementation based on a skeleton design for the method. This implementation offers, among others, the possibility for the user to instantiate the Tabu Search method for any problem with little e orts and basic knowledge of C++ language. The implementation provides both robustness and re-usability properties. We have instantiated the skeleton on three di erent problems, namely the Quadratic Assignment, Minimum k-Cardinality Tree and 0-1 Multi-dimensional Knapsack problems so as to evidence the claimed properties of the skeleton.

We show how to approximate in NC the problem of Scheduling Unrelated Parallel Machines, for a xed... more We show how to approximate in NC the problem of Scheduling Unrelated Parallel Machines, for a xed number of machines. We develop a (2 + ")-approximate parallel algorithm for the problem. Our approach shows how to relate the linear program obtained by relaxing the integer programming formulation of the problem with a linear program formulation that is positive and in the packing/covering form. The relationship established enables us to transfer approximate fractional solutions from the later formulation that is known to be approximable in NC. Then, we show how to obtain an integer approximate solution, i.e. a schedule, from the fractional one, using the randomized rounding technique. Finally, we show that the same technique can be applied to the General Assignment Problem of xed number of machines and a given makespan T , thus yielding a schedule whose cost is at most (2 + ") times the minimum cost and has makespan at most 2T.

Studies in Computational Intelligence, 2013

International Journal of Space-Based and Situated Computing, 2013

International Journal of Ad Hoc and Ubiquitous Computing, 2014

Proceedings of the IADIS International Conference E-Commerce 2008, IADIS Multi Conference on Computer Science and Information Systems 2008, 2008

In this paper, we reflect about the broadening of the field of application of CRM from the busine... more In this paper, we reflect about the broadening of the field of application of CRM from the business domain to a wider context of relationships in which the inclusion of non-profit making organizations seems natural. In particular, we focus on analyzing the suitability of adopting CRM processes by universities and higher educational institutions dedicated to elearning. This is an issue that, in our opinion, has much potential but has received little attention in research so far.