2,140 research outputs found

    S-MANAGE Protocol for Software-Defined IoT

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    © 2018 IEEE. The Internet of Things (IoT) has started to make a real impact with many IoT-based services in agriculture, smart farming, smart cities, personal health, and critical infrastructures. Sensor/IoT devices form one of the indispensable elements in these IoT systems and services. An effective IoT system requires the interoperability among its heterogeneous physical devices, but this presents a significant challenge regarding various communication protocols, networking management policies, as well as data processing approaches. Software-defined paradigm is considered essential for managing and provisioning IoT services on demand. An emerging solution is the application of software-defined networking (SDN) and Network Function Virtualization (NFV) in programming WSN/IoT systems. However, these technologies cannot be directly deployed due to the differences in the functionality of SDN network devices and sensor/IoT devices as well as the limitation of resources in IoT devices. We proposed the software-defined IoT(SD-IoT) model in our earlier work. This paper focuses on the S-MANAGE protocol that enables an SD-IoT controller to control and manage sensor/IoT devices via their virtual representation, called software-defined virtual sensors (SDVS). The paper presents in detail the design and the implementation of the S-MANAGE southbound protocol

    Design of a Workflow-Based Grid Framework

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    This paper aims to present the design of the Grid Collaborative Framework which has been proposed in one of our previous work. Grid infrastructure for resources sharing is somewhat stable with the wide acceptance of the Open Grid Services Architecture (OGSA) and Web Services Resource Framework (WSRF), but Grid framework for collaboration is far from desired. Current Grid Collaborative Frameworks (GCFs) are domain specific and lack of plan-supported capability. These limitations make them less useful and narrow in scope of application. Our grid collaborative framework aims to improve these limitations. With the theoretical foundation based on the activity theory, workflow languages, and designed on top of existing OGSA infrastructure, our proposed framework aims at accelerating the development of grid collaborative systems that consider work plans as central role

    Multi-level caching with delayed-multicast for video-on-demand

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    Delayed-Multicast is a novel transmission technique to support Video-on-Demand. It introduces buffers within the network to bridge the temporal delays between similar requests thus minimizing the aggregate bandwidth and server load. This paper introduces an improved online algorithm for resource allocation with Delayed-Multicast by utilizing prior knowledge of each clip's popularity. The algorithm is intended to be simple so as to allow for deployment at multiple levels in a distribution network. The result is greater backbone traffic savings and a corresponding reduction in the server load

    Can SDN Technology Be Transported to Software-Defined WSN/IoT?

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    © 2016 IEEE. Wireless sensor networks (WSNs) are essential elements of the Internet of Things ecosystem, as such, they encounter numerous IoT challenging architectural, management and application issues. These include inflexible control, manual configuration and management of sensor nodes, difficulty in an orchestration of resources, and virtualizing sensor network resources for on-demand applications and services. Addressing these issues presents a real challenge for WSNs and IoTs. By separating the network control plane from the data forwarding plane, Software-defined networking (SDN) has emerged as network technology that addresses similar problems of current switched-networks. Despite the differences between switched network and wireless sensor network domains, the SDN technology has a real potential to revolutionize WSNs/IoTs and address their challenging issues. However, very little has been attempted to bring the SDN paradigm to WSNs. This paper identifies weaknesses of existing research efforts that aims to bring the benefits of SDN to WSNs by mapping the control plane, the OpenFlow protocol, and the functionality between the two network domains. In particular, the paper investigates the difficulties and challenges in the development of software-defined wireless sensor networking (SDWSN). Finally, the paper proposes VSensor, SDIoT controller, SFlow components with specific and relevant functionality for an architecture of an SDWSN or SDIoT infrastructure

    Toward a programmable software-defined IoT architecture for sensor service provision on demand

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    © 2017 IEEE. In the age of Internet of Things (IoT), sensors form a foundational component of IoT services, yet they are rigid with little capability for programmable configuration or reusability as they are application-specific, manufacturer-specific. Emerging IoT applications often deploy a vast number of sensors which may serve multiple applications. Programmability is thus essential but not found in legacy or current generation sensors. It is challenging to effectively utilize heterogeneity of resources to handle a large number of application demands. Software Defined Networking (SDN) and Network Function Virtualization (NFV) have proved effective paradigms for provisioning services on-demand and managing network functions and their life cycles. This paper proposes a software defined IoT architecture that captures the spirit of SDN and NFV where a software-defined Internet of Things (SD-IoT) controller can provide services as requested by an application and also manage heterogeneous physical sensors through their virtual representation called software-defined virtual sensor (SD-VSensor) autonomously. In particular, the paper presents the design of a streamline SD-IoT controller, a lightweight and reconfigurable SD-VSensor, and the communication protocol (S-MANAGE) between them. The proposed architecture enables heterogeneous application-specific WSN systems to be recognized and effectively utilized by diverse IoT applications under the orchestration of the SD-IoT controller. Moreover, heterogeneity of sensor nodes or IoT devices can be programmed to achieve sensor services on demand. The preliminary implementation results demonstrate the feasibility and efficiency of the proposed architecture

    Leukocyte adhesion deficiency-I: A comprehensive review of all published cases

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    Leukocyte adhesion deficiency-I (LAD-I) is a rare, serious disorder with severity determined by defective CD18 expression. LAD-I is characterized by umbilical complications, granulocytosis, and diverse infections. Severe LAD-I is frequently fatal before the age of 2 years without allogeneic transplant. We identified 323 cases published between 1975 and 2017

    Stiff monolithic aerogel matrices for structural fibre composites

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    Resorcinol-formaldehyde based aerogel precursors were infused into structural carbon fibre weaves, then gelled and carbonised to generate a continuous monolithic matrix network. This hierarchical carbon preform was subsequently infused with polymeric resins, both multifunctional and structural, to produce dense composites. The resulting hierarchical composites have a nanoscale reinforcement in the matrix at up to an order of magnitude higher loadings than typically available by other techniques. Compression, tension, ±45° shear and short beam tests demonstrate the potential of such matrix systems to address matrix dominated failures. However, for the best structural performance it will be necessary to re-optimise the fibre-matrix interface, which is degraded by the current processing regime

    Mechanical and physical performance of carbon aerogel reinforced carbon fibre hierarchical composites

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    Carbon aerogel (CAG) is a potential hierarchical reinforcement to improve the matrix-dominated mechanical properties of continuous carbon fibre reinforced polymer (CFRP) composites in both multifunctional and purely structural applications. When using CAG to reinforce a polyethylene glycol diglycidyl ether (PEGDGE) matrix, the interlaminar shear strength, compressive modulus and strength increased approximately four-fold, whilst the out-of-plane electrical conductivity increased by 118%. These mechanical and electrical performance enhancements significantly improve the multifunctional efficiency of composite structural supercapacitors, which can offer weight savings in transport and other applications. However, CAG also has the potential to reinforce conventional continuous CF composites in purely structural contexts. Here, CAG reinforcement of structural epoxy resin composites marginally increased compressive (1.4%) and tensile (2.7%) moduli respectively, but considerably reduced compressive, tensile and interlaminar shear strengths. Fractographic analysis shows that the reduced performance can be attributed to poor interfacial adhesion; in the future, alternative processing routes may resolve these issues to achieve advances in both moduli and strengths over conventional structural CFRPs

    Protocol for an economic evaluation alongside a cluster randomised controlled trial: cost-effectiveness of Learning Clubs, a multicomponent intervention to improve women’s health and infant’s health and development in Vietnam

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    Introduction: Economic evaluations of complex interventions in early child development are required to guide policy and programme development, but a few are yet available. Methods and analysis: Although significant gains have been made in maternal and child health in resource- constrained environments, this has mainly been concentrated on improving physical health. The Learning Clubs programme addresses both physical and mental child and maternal health. This study is an economic evaluation of a cluster randomised controlled trial of the impact of the Learning Clubs programme in Vietnam. It will be conducted from a societal perspective and aims to identify the cost-effectiveness and the economic and social returns of the intervention. A total of 1008 pregnant women recruited from 84 communes in a rural province in Vietnam will be included in the evaluation. Health and cost data will be gathered at three stages of the trial and used to calculate incremental cost-effectiveness ratios per percentage point improvement of infant’s development, infant’s health and maternal common mental disorders expressed in quality-adjusted life years gained. The return on investment will be calculated based on improvements in productivity, the results being expressed as benefit–cost ratios. Ethics and dissemination: The trial was approved by Monash University Human Research Ethics Committee (Certificate Number 2016–0683), Australia, and approval was extended to include the economic evaluation (Amendment Review Number 2018-0683-23806); and the Institutional Review Board of the Hanoi School of Public Health (Certificate Number 017-377IDD- YTCC), Vietnam. Results will be disseminated through academic journals and conference presentations

    Structural supercapacitor composite technology demonstrator

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    Structural power composites, a class of multifunctional materials, have significant potential to facilitate lightweighting and accelerate widespread electrification in sustainable transportation. In civil aircraft, a bank of supercapacitors can provide power to open the doors in an emergency. Structural power composite fuselage components near the doors could provide this power and eliminate the mass and volume needed for the supercapacitors. To demonstrate this concept, we designed and manufactured a multifunctional component representative of a fuselage rib, which powered the opening and closing of a desktop scale composite aircraft door. This paper provides information about structural supercapacitor technology demonstrators, discusses the fabrication of this demonstrator and concludes by providing an insight into the future challenges that need to be addressed to realise structural power composite components
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