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Presentations are the most successful and popular form of communication in business. However, the formats of presentations in business have not changed much for past few decades. The emergent and disruptive technologies such as Augmented Reality and Animated Infographics have provided potential for enhancing communications in businesses to increase engagement and therefore increasing the effectiveness of such communications. This paper focuses on the impact and effectiveness of using interactive AR in business presentations. The paper presents the design and development of our AR presentation application. Followed by a presentation of an empirical study into the usability and effectiveness of using Augmented Reality and Animated Infographics in business presentation and compares the results against the traditional slideware slides presentation approach. The results of the experiment with 94 participants are presented and analysed. The results demonstrate that the AR approach out performs the traditional methods in terms of usability, audience engagement and effectiveness of communication.

Part of a collection: Software-Defined Networking (SDN) and Network Function Virtualization (NFV) for a Hyperconnected World: Challenges, Applications, and Major Advancements. Network programming and virtualization are technological trends being incrementally introduced in operational networks. This creates an environment where new innovations can be incorporated, facilitating also the evolution of the way in which existing services are delivered. These changes, however, are not only motivated by technical reasons. External factors, such as regulation, can trigger the evolution of existing services. Roaming services are an example of this two-sided situation. From the technical perspective, roaming users typically experiment worst performance than local users on the same network, since their traffic is usually routed through the home network. Besides that, due to recent regulation changes introduced in Europe for roaming services, known as Roam Like at Home (RLAH), roaming is charged at domestic prices. Both aspects are severely challenging the current mode of operation of roaming services as delivered nowadays by mobile operators. This paper presents the design of a virtualized based roaming solution, including an experimental assessment, as well as an economic insight of the concept. This work has been supported by the European Community through the 5GEx project within the H2020 programme (Grant agreement no. 671636). Special thanks to the teams of Deutsche Telekom and BISDN involved in H2020 EU 5GEx project that were part of the design and execution of this use case.

Next generation Web 2.0 communities and distributed P2P systems rely on the cooperation of diverse user populations spread across numerous administrative and security domains. Zero accountability via anonymous online identities and divergent interests result in selfish behavior that can disrupt or manipulate networks for personal gain. While “reputation systems” are recognized as a promising means to establish social control for such communities, developing reliable reputation systems remains a challenge. Several unaddressed threats still limit the effectiveness of reputation systems. Furthermore, most existing work on reputations has focused on accurate reputations for stable systems, but not examined the implications of integrating user reputations into scalable distributed infrastructures. The primary goal of this paper is to investigate and address the critical open challenges that limit the effectiveness of reputations. First, we identify a thorough taxonomy on reputation management, and use it as our framework to classify adversarial threats that compromise reliable operation of reputation systems. Second, we survey existing research to address these threats. Finally, we present our solutions to address the two leading reasons for erroneous and misleading values produced by reputation systems today, i.e., user collusion and short-lived online identities. We believe that this paper not only serves as an introduction to reputation systems design, but will also help researchers deploy reliable reputation solutions that contribute towards improving the performance of large distributed applications.

As one of the key techniques in wireless sensor networks (WSN), localization algorithm has been a research hot topic and indispensable function in most wireless applications. In order to promote localization accuracy and efficiency, a lot of localization algorithms with different performances and computation complexities have been proposed. The paper discusses the drawbacks of some typical works on localization, and proposes a hybrid localization algorithm integrated with approximate point in triangle (APIT) and distance vector-hop (DV-HOP). To address the positioning accuracy and coverage rate, the objectives of this paper are three folds: firstly, adopting angle detection to determine the exact direction of unknown nodes. Then, the APIT algorithm is adopted over all unknown nodes within the triangle and its localization error is reduced from 14.7215 m in conventional APIT to 3.2348 m in the considered scenario. Finally, the DV-HOP algorithm is adopted with different weights for the nodes within the minimum hops, and localizes the rest unknown nodes in WSN with localization accuracy increased by 49%.

A tremendous number of objective video quality measurement algorithms have been developed during the last two decades. Most of them either measure a very limited aspect of the perceived video quality or they measure broad ranges of quality with limited prediction accuracy. This paper lists several perceptual artifacts that may be computationally measured in an isolated algorithm and some of the modeling approaches that have been proposed to predict the resulting quality from those algorithms. These algorithms usually have a very limited application scope but have been verified carefully. The paper continues with a review of some standardized and well-known video quality measurement algorithms that are meant for a wide range of applications, thus have a larger scope. Their individual artifacts prediction accuracy is usually lower but some of them were validated to perform sufficiently well for standardization. Several difficulties and shortcomings in developing a general purpose model with high prediction performance are identified such as a common objective quality scale or the behavior of individual indicators when confronted with stimuli that are out of their prediction scope. The paper concludes with a systematic framework approach to tackle the development of a hybrid video quality measurement in a joint research collaboration. Polish National Centre for Research and Development (NCRD) SP/I/1/77065/10, Swedish Governmental Agency for Innovation Systems (Vinnova)

The Future Networks’ vision towards a diverse wireless networking world, considers the support of any service, at any time delivered in a transparent optimized way. The demand for multimedia services delivered “ anywhere and anyhow” has increased tremendously over the last few years leading to the evolution of the wireless industry towards all-IP networking. The research effort for the interworking heterogeneous technologies (e.g. WLANs, ad-hoc, wireless mesh, 4G, WiMAx, LTE etc.) amplifies the need to evaluate the conditions and restrictions to deliver these services. The QoS of multimedia services such as IP telephony, video-on-demand and mobile video will depend greatly on the ability to minimize the impact of the handover, hence traffic redirection in a seamless and secure transparent manner. Furthermore, Cross-layer and Cross-system optimization solutions will also be the enablers to deliver multimedia services over heterogeneous networks in a cost-effective manner. Themain objectives in this special issue are to address novel research results in the areas of resource andmobilitymanagement protocols and cross-layer techniques to facilitate effective cooperation among heterogeneouswireless networks thus enabling seamless servicemobility to the ‘end-user’ in an optimized way. The following papers have been included at this special issue: The first paper is entitled ‘Scalability Issues in Ad-Hoc Networks: Metrical Routing Versus Table-Driven Routing’ by Yosi Ben-Asher, Sharoni Feldman and Moran Feldman. They study the scalability of routing schemes for ad-hoc networks using explicit clustering. They compare an advanced version of the Ad Hoc Distance Vector Algorithm (AODV) by incorporating the Metrical Routing Algorithm (MRA) that possesses the natural clustering property. The second paper entitled ‘Timely Effective Handover Mechanism in Heterogeneous Wireless Networks’ by Sang-Jo Yoo, David Cypher, Nada Golmie propose a new predictive handover framework in order to achieve seamless handover in diverse wireless environments. Their approach uses the neighbor network information to generate timely the link triggers

Unlicensed ISM band is used by various wireless technologies. Therefore, issues related to ensuring the required efficiency and quality of operation of coexisting networks become essential. The paper addresses the problem of mutual interferences between IEEE 802.11b transmitters (commercially named Wi-Fi) and Bluetooth (BT) devices. An optimization approach to modeling the topology of BT scatternets is introduced, resulting in more efficient utilization of ISM environment consisting of BT and Wi-Fi networks. To achieve it, the Integer Linear Programming approach has been proposed. Example results presented in the paper illustrate significant benefits of using the proposed modeling strategy.

This paper reports on the lessons learnt during the application of a methodology to develop intelligent environments. One important feature of the methodology is that of being strongly user-centred, and the authors report on how that interaction with users took place and how it continuously shaped our project aspirations and outcomes. The methodology was applied to a project which aimed at helping people with Down’s Syndrome and those with similar conditions and needs, to be more included in society. The project was developed by a consortium of commercial, academic, and end user supporting organizations. The paper elaborates on what type of stakeholders engaging activities were considered and how these were distributed along the lifetime of the project and their impact.

This paper is devoted to the problem of the WKB method inaccuracy. By comparing the WKB with a reference finite-element numerical method we show the magnitude of the WKB solution error. Moreover, we show in the paper what kind of simplifications made in the WKB analytical approximation led to its inaccuracy.

Displays are the most visible part of most computer applications. Novel display technologies strongly influence and inspire new forms of computer use and interaction. We are particularly interested in the interplay of novel displays and interaction for ubiquitous computing or ambient media environments, as emerging display technologies may become game-changers in how we define and use computers, possibly changing the context of computing fundamentally. We present some of our experiments and lessons learnt with a new category of displays, the "immaterial" FogScreen. It can be described as a novel media platform, exhibiting some fundamental differences to and advantages over other displays. It also enables novel kinds of user interfaces and experiences. In this paper we give insights about the special properties and strengths of the FogScreen by looking at a set of successfully demonstrated interfaces and applications. We also discuss its future potential for user interface design.

Despite strong interest in peer-to-peer (P2P) Video-on-Demand (VoD) services, existing studies mostly focus on peer-to-peer or overlay protocol design based on simulations under various topological constraints. We believe experimental studies on a real-life P2P VoD system will provide valuable information to ISPs, network administrators, and content owners. In this paper we present a comprehensive analytical and experimental study on Joost, one of the first commercial P2P VoD systems used for distributing various forms of video over the Internet. Our extensive experiments prove that Joost is a server-assisted peer-to-peer VoD system. With several envisioned typical scenarios we have further investigated the peer management in terms of time pattern, bandwidth consumption and locality considerations. Our major findings include: (1) the current Joost system is capable of providing high-quality VoD service through the use of an overlay network deployed with a set of centralized content servers; (2) inter-continental links are often used regardless of the number of local users, which may pose a high burden on the network providers; (3) easily reachable, high-capacity nodes are selected as main relaying nodes, similar to super nodes in Skype, to facilitate the traversal of symmetric NATs and firewalls. We also provide insights on the potential ways to construct more efficient P2P VoD systems (e.g. considering topological locality-awareness, using adaptive/layered video). peerReviewed

The Internet of Things (IoT) is an emerging network paradigm, and realizes the interconnection among ubiquitous things, along with its corresponding applications and services in both Physical-world and Cyber-world. Some researches have been worked on IoT modeling and addressing, which are mainly based on objects with a unique identifier (ID). However, in practical scenarios, there are several objects without any available ID, namely non-ID (i.e., nID) physical objects, including the objects unattached any ID itself, and the objects attached unreadable or un-trusted ID. It turns out that the nID physical objects related issues become noteworthy. In this paper, we focus on the nID physical objects to present a modeling and addressing solution. Concretely, (1) nID physical objects are described along with the discussion of applying nID solution; (2) a tree-like code structure (i.e., Tree-Code) is introduced to establish a unified modeling scheme for the nID physical objects according to abstracted data elements, and also achieves the compatibility with the ID physical objects considering the ID based data elements; (3) Tree-Code based addressing scheme is presented with dynamic updating considerations. It indicates that the nID physical object modeling and addressing provide complements to the ID physical objects for ubiquitous interactions in the IoT.

Mobile ad hoc networks are vulnerable to a large group of attacks, e.g., wormhole attacks. In this paper, we propose a countermeasure to prevent wormhole attacks. We utilize analytical hierarchy process to elect some special nodes, named the local most trustable nodes, for the source and the destination node, respectively. The elected nodes are then required to implement our proposed scheme to prevent wormhole attacks. The proposed scheme cannot only detect wormhole attacks, but also locate wormhole nodes, i.e., identify the malicious nodes that behave wormhole attacks. To solve the colluding wormhole attack, we present a countermeasure named bi-directional wormhole location mechanism.

Narrow band gap photon infrared detectors require cryogenic cooling to suppress the noise deteriorating the performance. Among the competitive materials and theoretical predictions favouring type-II superlattices InAs/GaSb, HgCdTe has been still considered as the leader in terms of the fundamental physical parameters. The size, weight, power consumption and multispectral response of the infrared detection system play decisive role in fabrication of the higher operation temperature detectors. Several strategies have been implemented to improve the performance at elevated temperatures. The most efficient and used in HgCdTe technology are: non-equilibrium architectures and currently an idea of the barrier detectors. In this paper we present the comparison of the \(\hbox {nB}_\mathrm{n}\hbox {n}\) and \(\hbox {pB}_\mathrm{p}\hbox {p}\,(\hbox {B}_\mathrm{n}\) and \(\hbox {B}_\mathrm{p}\) stands for n/p-type doped barrier) HgCdTe photodetectors. \(\hbox {pB}_\mathrm{p}\hbox {p}\) architecture allows to reach higher performance (detectivity \({\sim }10^{9}\,\hbox {cm}\,\hbox {Hz}^{1/2}/\mathrm {W}\) for \(T = 200\) K) at mid-wave spectrum for wide range of absorber p-type doping \(2\times 10^{14}\rightarrow 10^{17}\,\hbox {cm}^{-3}\) and barrier Cd composition \(0.37\rightarrow 0.7\).

The paper discusses several theoretical and implementational problems of interval branch-and-bound methods. A trial to define a class of problems that can be solved with such methods is done. Features and variants of the method are presented. Useful data structures and shared-memory parallelization issues are considered.

Network-layer mobility protocols have been developed to keep continuous connectivity for mobile hosts while transparent to the higher layers. However, Due to its distinct characteristics of different from traditional TCP/IP environment, mobility poses substantial impacts on TCP performance in mobile environments. This paper proposes a new cross-layer approach, by introducing a mobility detection element in the network layer which interacts with the transport layer to optimize TCP operations. As changes are only made to the endpoints, this approach preserves the end-to-end semantics of TCP. Different from most exiting works, which utilize either transport or network layer alone without much cross-layer cooperation, our approach allows the use of mobility information in TCP. We analytically compare this approach against existing approaches and show that our approach outperforms prior approaches in terms of effective data resumption time. Through performance simulations, our approach demonstrates that it can effectively improve TCP performance in Mobile IPv6-based mobile environments. peerReviewed

We propose to use the blind deconvolution and its modification to extract the point spread function (PSF) of layered metamaterials from a SNOM measurement. The measurement results are processed using the blind deconvolution algorithm to reconstruct the real-valued non-coherent PSF, or using the modified blind deconvolution introduced in this paper to reconstruct the complex-valued coherent PSF. The two algorithms are tested in simulations with a layered metamaterial deposited on a thin metallic mask with test apertures. We show that the modified algorithm is capable of recovering the approximate shape of complex PSF with a sub-wavelength full width at half maximum from a measurement in which the apertures are larger than the wavelength.

This paper studies an infinite-server queue in a random environment, meaning that the arrival rate, the service requirements and the server work rate are modulated by a general c\`{a}dl\`{a}g stochastic background process. To prove a large deviations principle, the concept of attainable parameters is introduced. Scaling both the arrival rates and the background process, a large deviations principle for the number of jobs in the system is derived using attainable parameters. Finally, some known results about Markov-modulated infinite-server queues are generalized and new results for several background processes and scalings are established in examples., Comment: 28 pages, 2 figures

In this paper, we explore the integration of evolutionary computation into the development and run-time support of dynamically-adaptable, high-assurance middleware. The open-ended nature of the evolutionary process has been shown to discover novel solutions to complex engineering problems. In the case of high-assurance adaptive software, however, this search capability must be coupled with rigorous development tools and run-time support to ensure that the resulting systems behave in accordance with requirements. Early investigations are reviewed, and several challenging problems and possible research directions are discussed.

An improved DV-HOP localization algorithm is proposed based on the traditional DV-HOP localization algorithm in the paper. There will be a big error that using the nearest anchor node's average hop distance instead of the average hop distance of all the anchor nodes that involved in the localizing in the traditional DV-HOP localization algorithm. Therefore, the improved algorithm introduces threshold M, it uses the weighted average hop distances of anchor nodes within M hops to calculate the average hop distance of unknown nodes. In addition, the positioning results are corrected in the improved algorithm. The simulation results show that the new localization algorithm effectively improves the positioning accuracy compared with the traditional DV-HOP localization algorithm, it is an effective localization algorithm in the wireless sensor networks.

Background Many physicians are transitioning from paper to electronic formats for billing, scheduling, medical charts, communications, etc. The primary objective of this research was to identify the relationship (if any) between the software selection process and the office staff's perceptions of the software's impact on practice activities. Methods A telephone survey was conducted with office representatives of 407 physician practices in Oregon who had purchased information technology. The respondents, usually office managers, answered scripted questions about their selection process and their perceptions of the software after implementation. Results Multiple logistic regression revealed that software type, selection steps, and certain factors influencing the purchase were related to whether the respondents felt the software improved the scheduling and financial analysis practice activities. Specifically, practices that selected electronic medical record or practice management software, that made software comparisons, or that considered prior user testimony as important were more likely to have perceived improvements in the scheduling process than were other practices. Practices that considered value important, that did not consider compatibility important, that selected managed care software, that spent less than $10,000, or that provided learning time (most dramatic increase in odds ratio, 8.2) during implementation were more likely to perceive that the software had improved the financial analysis process than were other practices. Conclusion Perhaps one of the most important predictors of improvement was providing learning time during implementation, particularly when the software involves several practice activities. Despite this importance, less than half of the practices reported performing this step.

This paper combines analytical approximations for the optical absorption and luminescence of semiconductors with Trust Region-Reflective (TRR) methods methods, delivering a robust numerical characterization method to be used in the study of new bulk semiconductors per direct comparison with experimental spectra. It further extends recent applications of the theory to the case of dilute nitride semiconductors and confirms results for the s-shape of the luminescence peak as a function of temperature.

Background Cloud computing is a new paradigm that is changing how enterprises, institutions and people understand, perceive and use current software systems. With this paradigm, the organizations have no need to maintain their own servers, nor host their own software. Instead, everything is moved to the cloud and provided on demand, saving energy, physical space and technical staff. Cloud-based system architectures provide many advantages in terms of scalability, maintainability and massive data processing. Methods We present the design of an e-health cloud system, modelled by an M/M/m queue with QoS capabilities, i.e. maximum waiting time of requests. Results Detailed results for the model formed by a Jackson network of two M/M/m queues from the queueing theory perspective are presented. These results show a significant performance improvement when the number of servers increases. Conclusions Platform scalability becomes a critical issue since we aim to provide the system with high Quality of Service (QoS). In this paper we define an architecture capable of adapting itself to different diseases and growing numbers of patients. This platform could be applied to the medical field to greatly enhance the results of those therapies that have an important psychological component, such as addictions and chronic diseases.

In this paper we present a novel Code Execution Framework that can execute code of different problem solving environments (PSE), such as MATLAB, R and Octave, in parallel. In many e-Science domains different specialists are working together and need to share data or even execute calculations using programs created by other persons. Each specialist may use a different problem solving environment and therefore the collaboration can become quite difficult. Our framework supports different cloud platforms, such as Amazon Elastic Compute Cloud (EC2) and Eucalyptus. Therefore it is possible to use hybrid cloud infrastructures, e.g. a private cloud based on Eucalyptus for general base-level computations using the available local resources and additionally a public Amazon EC2 for peaks and time-dependent calculations. Our approach is to provide a secure platform that supports multiple problem solving environments, execute code in parallel with different parameter sets using multiple cores or machines in a cloud environment, and support researchers in executing code, even if the required problem solving environment is not installed locally. Additionally, existing parallel resources can easily be utilized for ongoing scientific calculations. The framework has been validated by and used in our real project addressing large-scale breath analysis research. Its research-prototype version is available as a PaaS cloud service model. In the future researchers will be able to install this framework on their own cloud infrastructures.

Trust is a critical factor in cloud computing; in present practice it depends largely on perception of reputation, and self assessment by providers of cloud services. We begin this paper with a survey of existing mechanisms for establishing trust, and comment on their limitations. We then address those limitations by proposing more rigorous mechanisms based on evidence, attribute certification, and validation, and conclude by suggesting a framework for integrating various trust mechanisms together to reveal chains of trust in the cloud.

In this paper we report upon the cloud-based solution that we designed and implemented for space situational awareness. We begin by introducing the background to the work and to the area of space situational awareness. This concerns tracking the hundreds of thousands of known objects in near-Earth orbits, and determining where it is necessary for satellite operators to conduct collision-avoidance manoeuvres to protect their satellites. We also discuss active debris removal, which would be necessary to stabilise the debris population at current levels. We examine the strengths that cloud-based solutions offer in general and how these specifically fit to the challenges of space situational awareness, before describing the architecture we designed for this problem. We demonstrate the feasibility of solving the space situational awareness problem with a cloud-based architecture and note that as time goes on and debris levels rise due to future collisions, the inherent scalability offered by a cloud-based solution will be invaluable.

This special issue presents extended and revised versions of distinguished papers presented at the security & privacy track of the 3rd IEEE International Conference on Cloud Computing Technology and Science (IEEE Cloudcom 2011).