10 research outputs found

    A Smart Game for Data Transmission and Energy Consumption in the Internet of Things

    Get PDF
    The current trend in developing smart technology for the Internet of Things (IoT) has motivated a lot of research interest in optimizing data transmission or minimizing energy consumption, but with little evidence of proposals for achieving both objectives in a single model. Using the concept of game theory, we develop a new MAC protocol for IEEE 802.15.4 and IoT networks in which we formulate a novel expression for the players' utility function and establish a stable Nash equilibrium (NE) for the game. The proposed IEEE 802.15.4 MAC protocol is modeled as a smart game in which analytical expressions are derived for channel access probability, data transmission probability, and energy used. These analytical expressions are used in formulating an optimization problem (OP) that maximizes data transmission and minimizes energy consumption by nodes. The analysis and simulation results suggest that the proposed scheme is scalable and achieves better performance in terms of data transmission, energy-efficiency, and longevity, when compared with the default IEEE 802.15.4 access mechanism.Peer reviewe

    A Dynamic Game with Adaptive Strategies For IEEE 802.15.4 and IoT

    Get PDF
    © 2016 IEEE. This is the accepted manuscript version of a conference paper which has been published in final form at https://doi.org/10.1109/TrustCom.2016.0099The problem of selfishness and misbehaviour in wireless networks is well known, as are the associated solutions that have been proposed for it in IEEE 802.11 Wireless Local Area Network (WLAN) and Wireless Sensory Network (WSN). However, tackling such problem in relation to the Internet of Things (IoT) is relatively new since the IoT is still under development. The central communication infrastructure of IoT is the IEEE 802.15.4 standard which defines low-rate and low energy wireless personal area networks. In order to share the medium fairly and efficiently in a beacon-enabled mode, the standard uses Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) in the Contention Access Period (CAP), and Guarantee Time Slot (GTS) in the Contention Free Period (CFP) of a super-frame. These channel sharing mechanisms are known to be vulnerable to selfishness, misbehaviour and channel capture as a result of nodes disobeying the communication rules. Most of the existing game theoretic solutions were designed for IEEE 802.11 WLAN and WSN. In this work, we present a dynamic game in which nodes can select and adapt their strategies of play according to the 'state of the game' and their energy level in order to increase their utility whenever their utility declined. Our model enables resources constrained nodes to optimised their strategies individually based upon the current state of the game and their available resources. Our analysis and simulation results suggest an improvement in utility, and fairness in channel sharing, as well as efficiency in energy usage in our dynamic model and hence performance and security in our scheme over the default IEEE 802.15.4 access mechanism

    A Resilient MAC Protocol for Wireless Networks

    Get PDF
    Paper presented at the IMA Conference on Game Theory and its Applications, Oxford, 8/12/2014Peer reviewe

    Global Mental Health: From Science to Action

    Get PDF
    This article charts the historical development of the discipline of global mental health, whose goal is to improve access to mental health care and reduce inequalities in mental health outcomes between and within nations. The article begins with an overview of the contribution of four scientific foundations toward the discipline's core agenda: to scale up services for people with mental disorders and to promote their human rights. Next, the article highlights four recent, key events that are indicative of the actions shaping the discipline: the Mental Health Gap Action Programme to synthesize evidence on what treatments are effective for a range of mental disorders; the evidence on task shifting to nonspecialist health workers to deliver these treatments; the Movement for Global Mental Health's efforts to build a common platform for professionals and civil society to advocate for their shared goal; and the Grand Challenges in Global Mental Health, which has identified the research priorities that, within the next decade, can lead to substantial improvements in the lives of people living with mental disorders. The article ends by examining the major challenges for the field, and the opportunities for addressing them in the future. (harv rev psychiatry 2012;20:6–12.

    "The contribution of chronic diseases to the prevalence of dependence among older people in Latin America, China and India: a 10/66 Dementia Research Group population-based survey"

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The number of older people is set to increase dramatically worldwide. Demographic changes are likely to result in the rise of age-related chronic diseases which largely contribute to years lived with a disability and future dependence. However dependence is much less studied although intrinsically linked to disability. We investigated the prevalence and correlates of dependence among older people from middle income countries.</p> <p>Methods</p> <p>A one-phase cross-sectional survey was carried out at 11 sites in seven countries (urban sites in Cuba, Venezuela, and Dominican Republic, urban and rural sites in Peru, Mexico, China and India). All those aged 65 years and over living in geographically defined catchment areas were eligible. In all, 15,022 interviews were completed with an informant interview for each participant. The full 10/66 Dementia Research Group survey protocol was applied, including ascertainment of depression, dementia, physical impairments and self-reported diagnoses. Dependence was interviewer-rated based on a key informant's responses to a set of open-ended questions on the participant's needs for care. We estimated the prevalence of dependence and the independent contribution of underlying health conditions. Site-specific prevalence ratios were meta-analysed, and population attributable prevalence fractions (PAPF) calculated.</p> <p>Results</p> <p>The prevalence of dependence increased with age at all sites, with a tendency for the prevalence to be lower in men than in women. Age-standardised prevalence was lower in all sites than in the USA. Other than in rural China, dementia made the largest independent contribution to dependence, with a median PAPF of 34% (range 23%-59%). Other substantial contributors were limb impairment (9%, 1%-46%), stroke (8%, 2%-17%), and depression (8%, 1%-27%).</p> <p>Conclusion</p> <p>The demographic and health transitions will lead to large and rapid increases in the numbers of dependent older people particularly in middle income countries (MIC). The prevention and control of chronic neurological and neuropsychiatric diseases and the development of long-term care policies and plans should be urgent priorities.</p

    Onchocerciasis (river blindness) – more than a century of research and control

    Get PDF
    This review summarises more than a century of research on onchocerciasis, also known as river blindness, and its control. River blindness is an infection caused by the tissue filaria Onchocerca volvulus affecting the skin, subcutaneous tissue and eyes and leading to blindness in a minority of infected persons. The parasite is transmitted by its intermediate hosts Simulium spp. which breed in rivers. Featured are history and milestones in onchocerciasis research and control, state-of-the-art data on the parasite, its endobacteria Wolbachia, on the vectors, previous and current prevalence of the infection, its diagnostics, the interaction between the parasite and its host, immune responses and the pathology of onchocerciasis. Detailed information is documented on the time course of control programmes in the afflicted countries in Africa and the Americas, a long road from previous programmes to current successes in control of the transmission of this infectious disease. By development, adjustment and optimization of the control measures, transmission by the vector has been interrupted in foci of countries in the Americas, in Uganda, in Sudan and elsewhere, followed by onchocerciasis eliminations. The current state and future perspectives for control, elimination and eradication within the next 20–30 years are described and discussed. This review contributes to a deeper comprehension of this disease by a tissue-dwelling filaria and it will be helpful in efforts to control and eliminate other filarial infections

    SEVA: A Smart Electronic Voting Application Using Blockchain Technology

    Get PDF
    © 2021 IEEE.The development of electronic voting applications remains an active area of research and this has led to the proposal and implementation of many models based on blockchains. However, most of the proposed models are partially decentralized solutions, in which the blockchain is used as a storage media for votes while the application is written in programming tools such as HTML, CSS, and JavaScript. This makes them vulnerable to attacks such as Denial of Service (DoS) attacks, Single Point of Failure (SPF), and fraudulent record modification. In this paper, we propose a fully decentralized electronic voting application, SEVA, in which we placed the whole application (code and data) in Ethereum to protect the application from vul- nerabilities. Additionally, we propose a new consensus algorithm, Proof of Smart Vote (PoSV) for SEVA, as a viable energy-saving alternative to the energy-intensive Proof of Work (PoW). We implemented and evaluated SEVA with PoSV and compared it with a partially decentralized model of the application.Peer reviewedFinal Accepted Versio
    corecore