12 research outputs found

    Tag anti-collision algorithms in RFID systems - a new trend

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    RFID is a wireless communication technology that provides automatic identification or tracking and data collection from any tagged object. Due to the shared communication channel between the reader and the tags during the identification process in RFID systems, many tags may communicate with the reader at the same time, which causes collisions. The problem of tag collision has to be addressed to have fast multiple tag identification process. There are two main approaches to the tag collision problem: ALOHA based algorithms and tree based algorithms. Although these methods reduce the collision and solve the problem to some extent, they are not fast and efficient enough in real applications. A new trend emerged recently which takes the advantages of both ALOHA and tree based approaches. This paper describes the process and performance of the tag anti-collision algorithms of the tree-ALOHA trend

    FRAMEWORK FOR IMPROVING PERFORMANCE OF PROTOCOLS FOR READING RADIO FREQUENCY IDENTIFICATION TAGS

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    Radio-frequency Identification (RFID) is a highly sought-after wireless technology used to track and manage inventory in the supply chain industry. It has varied applications ranging from automated toll collection and security access management to supply chain logistics. Miniaturization and low tag costs of RFID tags have lead to item-level tagging, where not just the pallet holding products is tagged but each product inside has a tag attached to it. Item-level tagging of goods improves the accuracy of the supply chain but it significantly increases the number of tags that an RFID reader must identify and track. Faster identification is crucial to cutting cost and improving efficiency. Existing RFID protocols were designed to primarily handle static scenarios with both RFID tags and readers not being in motion. This research addresses the problem of inventory tracking within a warehouse in multitude of scenarios that involves mobile tags, multiple readers and high density environments. Mobility models are presented and frameworks are developed for the following scenarios: a) mobile tags on a conveyor belt with multiple fixed readers; b) mobile reader in a warehouse with stationary tags in shelves; and c) high density tag population with Near-Field (NF) communication. The proposed frameworks use information sharing among readers to facilitate protocol state handoff and segregation of tags into virtual zones to improve tag reading rates in mobile tag and mobile reader scenarios respectively. Further, a tag’s ability to listen to its Near-Field neighboring tags transmissions is exploited to assist the reader in resolving collisions and hence enhancing throughput. The frameworks discussed in this research are mathematically modeled with a probabilistic analysis of protocols employed in conjunction with framework. With an increased number of tags to be identified, mathematically understanding the performance of the protocol in these large-scale RFID systems becomes essential. Typically, this analysis is performed using Markov-chain models. However, these analyses suffer from the common state-space explosion problem. Hence, it is essential to come up with a scalable analysis, whose computation model is insensitive to the number of tags. The following research analyzes the performance of tag identification protocols in highly dense tag scenarios, and proposes an empirical formula to estimate the approximate time required to read all the tags in a readers range without requiring protocol execution

    Energy efficiency in short and wide-area IoT technologies—A survey

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    In the last years, the Internet of Things (IoT) has emerged as a key application context in the design and evolution of technologies in the transition toward a 5G ecosystem. More and more IoT technologies have entered the market and represent important enablers in the deployment of networks of interconnected devices. As network and spatial device densities grow, energy efficiency and consumption are becoming an important aspect in analyzing the performance and suitability of different technologies. In this framework, this survey presents an extensive review of IoT technologies, including both Low-Power Short-Area Networks (LPSANs) and Low-Power Wide-Area Networks (LPWANs), from the perspective of energy efficiency and power consumption. Existing consumption models and energy efficiency mechanisms are categorized, analyzed and discussed, in order to highlight the main trends proposed in literature and standards toward achieving energy-efficient IoT networks. Current limitations and open challenges are also discussed, aiming at highlighting new possible research directions

    Intelligent Sensor Networks

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    In the last decade, wireless or wired sensor networks have attracted much attention. However, most designs target general sensor network issues including protocol stack (routing, MAC, etc.) and security issues. This book focuses on the close integration of sensing, networking, and smart signal processing via machine learning. Based on their world-class research, the authors present the fundamentals of intelligent sensor networks. They cover sensing and sampling, distributed signal processing, and intelligent signal learning. In addition, they present cutting-edge research results from leading experts

    Maritime Transport ‘16

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    Legal and regulatory aspects of mobile financial services

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    The thesis deals with the emergence of bank and non-bank entities that provide a range of unique transaction-based payment services broadly called Mobile Financial Services (MFS) to unbanked, underserved and underbanked persons via mobile phones. Models of MFS from Mobile Network Operators (MNOs), banks, combinations of MNOs and banks, and independent Mobile Financial Services Providers are covered. Provision by non-banks of ‘bank-type’ services via mobile phones has been termed ‘transformational banking’ versus the ‘additive banking’ services from banks. All involve the concept of ‘branchless banking’ whereby ‘cash-in/cash out’ services are provided through ‘agents.’ Funds for MFS payments may available through a Stored Value Product (SVP), particularly through a Stored Value Account SVP variant offered by MNOs where value is stored as a redeemable fiat- or mobile ‘airtime’-based Store of Value. The competitive, legal, technical and regulatory nature of non-bank versus bank MFS models is discussed, in particular the impact of banking, payments, money laundering, telecommunications, e-commerce and consumer protection laws. Whether funding mechanisms for SVPs may amount to deposit-taking such that entities could be engaged in the ‘business of banking’ is discussed. The continued use of ‘deposit’ as the traditional trigger for the ‘business of banking’ is investigated, alongside whether transaction and paymentcentric MFS rises to the ‘business of banking.’ An extensive evaluation of ‘money’ based on the Orthodox and Claim School economic theories is undertaken in relation to SVPs used in MFS, their legal associations and import, and whether they may be deemed ‘money’ in law. Consumer protection for MFS and payments generally through current statute, contract, and payment law and common law condictiones are found to be wanting. Possible regulatory arbitrage in relation to MFS in South African law is discussed. The legal and regulatory regimes in the European Union, Kenya and the United States of America are compared with South Africa. The need for a coordinated payments-specific law that has consumer protections, enables proportional risk-based licensing of new non-bank providers of MFS, and allows for a regulator for retail payments is recommended. The use of trust companies and trust accounts is recommended for protection of user funds. | viPublic, Constitutional and International LawLL. D

    Applying system dynamics modelling to building resilient logistics : a case of the Humber Ports Complex

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    This research employs system dynamics modelling to analyse the structural behaviour of the interactions between Disaster Preparedness, Environment Instability, and Resilience in maritime logistics chain as a response to policy change, or strategic risk management interventions, at ports on the Humber Estuary.Port authorities, logistics operators, agencies, transporters, and researchers have revealed that disasters lead to interruptions in free flow of supply chains, and has the potential to disrupt the overall performance of a logistics chain. There is strong evidence about the rise in frequency, magnitude, and disruption potentials of catastrophic events in recent times (e.g. 9/11 attack, the Japanese earthquake/Tsunami and the aftermath nuclear disaster, Hurricanes Katrina and Haiyan, Super Storm Sandy, and many more). However, it appears that risk managers are not able to anticipate the outcomes of risk management decisions, and how those strategic interventions can affect the future of the logistics chain. Management appears to misjudge (or miscalculate) risks, perhaps due to the assumed complexity, the unpredictability of associated disruptions, and sometimes due to individual managerial approach to risk management. The uncertainties and states assumed notwithstanding, investors and regulators have become increasingly intolerant for risk mismanagement. Shipowners and port authorities tend to managing cost instead of managing risk. Hence they appear to invest little time and fewer resources in managing disruptions in their logistics chains even though they seem to frequently conduct risk assessments. We suggest that disaster preparedness that leads to resilience in maritime logistics chain is the best alternative to preventing or reducing the impacts of disruptions from catastrophes.We aim at improving current level of understanding the sources of disruptions in port/maritime logistics system through analysing the interdependencies between key variables. The dynamic models from this research have revealed that there is strong influence relationships (interdependencies) between Disaster Preparedness, Environment Instability, and Resilience. We found that potential sources of disruptions along the spokes of maritime logistics system can be port physics related, however the subtle triggering factors appear to be port size related. We also found that policy interventions geared towards risk management have the potential to produce unintended consequences basically due to unacknowledged conditions. Thus the relevance of the research and the SD models was to provide strategic policy makers with real-time decision evaluation tool that can provide justification for acceptance or rejection of a risk management intervention prior to decision implementation

    Solutions for large scale, efficient, and secure Internet of Things

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    The design of a general architecture for the Internet of Things (IoT) is a complex task, due to the heterogeneity of devices, communication technologies, and applications that are part of such systems. Therefore, there are significant opportunities to improve the state of the art, whether to better the performance of the system, or to solve actual issues in current systems. This thesis focuses, in particular, on three aspects of the IoT. First, issues of cyber-physical systems are analysed. In these systems, IoT technologies are widely used to monitor, control, and act on physical entities. One of the most important issue in these scenarios are related to the communication layer, which must be characterized by high reliability, low latency, and high energy efficiency. Some solutions for the channel access scheme of such systems are proposed, each tailored to different specific scenarios. These solutions, which exploit the capabilities of state of the art radio transceivers, prove effective in improving the performance of the considered systems. Positioning services for cyber-physical systems are also investigated, in order to improve the accuracy of such services. Next, the focus moves to network and service optimization for traffic intensive applications, such as video streaming. This type of traffic is common amongst non-constrained devices, like smartphones and augmented/virtual reality headsets, which form an integral part of the IoT ecosystem. The proposed solutions are able to increase the video Quality of Experience while wasting less bandwidth than state of the art strategies. Finally, the security of IoT systems is investigated. While often overlooked, this aspect is fundamental to enable the ubiquitous deployment of IoT. Therefore, security issues of commonly used IoT protocols are presented, together with a proposal for an authentication mechanism based on physical channel features. This authentication strategy proved to be effective as a standalone mechanism or as an additional security layer to improve the security level of legacy systems

    Combining SOA and BPM Technologies for Cross-System Process Automation

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    This paper summarizes the results of an industry case study that introduced a cross-system business process automation solution based on a combination of SOA and BPM standard technologies (i.e., BPMN, BPEL, WSDL). Besides discussing major weaknesses of the existing, custom-built, solution and comparing them against experiences with the developed prototype, the paper presents a course of action for transforming the current solution into the proposed solution. This includes a general approach, consisting of four distinct steps, as well as specific action items that are to be performed for every step. The discussion also covers language and tool support and challenges arising from the transformation
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