267 research outputs found

    Load and Energy Aware Hybrid Routing Protocol for Hybrid Wireless Mesh Networks

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    High-Speed Wireless Personal Area Networks: An Application of UWB Technologies

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    A Quality Hybrid Service Discovery Protocol

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    Hybrid protocol combines the advantages of proactive and reactive routing in adhoc network. The routing is initially established with some proactively prospected routes and then serves the demand from additionally activated nodes through reactive flooding. In this paper we propose A Quality Hybrid Service Discovery Protocol (QHSDP) for discovering services. A broadcast mechanism is used to get the service and routing information of the nodes present inside the zone. The routing and service information reduces the packet flooding in the network hence reducing collision and increasing packet delivery efficiency. Reduced control packets in turn reduces the battery power consumption. A query message is bordercasted through the peripheral nodes to the nodes outside the zone. This makes the discovery procedure more sclable, hence increasing the node’s coverage and reducing the latency in the proposed technology compared to the existing technolog

    Semantically Intelligent Distributed Leader Election (SIDLE) Algorithm for WSAN Part of IoT Systems

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    This paper introduces the deployment of a group of Wireless Sensor and Actuator Network (WSAN) part of Internet of Thing (IoT) systems in rural regions deployed by a drone dropping sensors and actuators at a certain position as a mesh of a hexagonal form. Nodes are heterogeneous in hardware and functionality thus not all nodes are able to transfer data directly to the base station. Primitive ones are only capable of collecting local data. However, ones that are more sophisticated are equipped with long-range radio telemetry and more computational power. Power optimization is one of the crucial factors in designing WSANs. Total power consumption must be minimized, as sensors are self-managed. It is not feasible to collect sensors on time bases and recharge the batteries. Therefore, energy consumption optimization and harvesting green energy are other factors that are considered. In this regard, protocols are designed in a way to support such requirements. The preprocessed data are first collected and combined by the leaders at each hexagonal cell. Then, the information packets are sent to the head clusters. Consequently, head clusters reprocess the received information and depict a better global view of the zone, using a variety of the received information. Finally, the processed information is sent to the nearest base station or a mobile drone.Comment: The First International Conference of Smart City, 2019, Apadana University, Shiraz, Iran https://www.civilica.com/Paper-SMARTCITYC01-SMARTCITYC01_100.htm

    Towards Stable Electrochemical Sensing for Wearable Wound Monitoring

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    Wearable biosensing has the tremendous advantage of providing point-of-care diagnosis and convenient therapy. In this research, methods to stabilize the electrochemical sensing response from detection of target biomolecules, Uric Acid (UA) and Xanthine, closely linked to wound healing, have been investigated. Different kinds of materials have been explored to address such detection from a wearable, healing platform. Electrochemical sensing modalities have been implemented in the detection of purine metabolites, UA and Xanthine, in the physiologically relevant ranges of the respective biomarkers. A correlation can be drawn between the concentrations of these bio-analytes and wound severity, thus offering probable quantitative insights on wound healing progression. These insights attempt to contribute in reducing some impacts of the financial structure on the healthcare economy associated with wound-care. An enzymatic electrochemical sensing system was designed to provide quick response at a cost-effective, miniaturized scale. Robust enzyme immobilization protocols have assisted in preserving enzyme activity to offer stable response under relevant variations of temperature and pH, from normal. Increased hydrophilicity of the sensor surface using corona plasma, has assisted in improving conductivity, thus allowing for increased electroactive functionalization and loading across the substrate’s surface. Superior sensor response was attained from higher loading of nanomaterials (MWCNT/AuNP) and enzymes (UOx/XO) employed in detection. Potentiometric analyses of the nanomaterial modified enzymatic biosensors were conducted using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) modalities. Under relevant physiological conditions, the biosensor was noted to offer a variation in response between 10 % and 30 % within a week. Stable, reproducible results were obtained from repeated use of the biosensor over multiple days, also offering promise for continuous monitoring. Shelf life of the biosensor was noted to be more than two days with response retained by about 80 % thereafter. Secondary analyses have been performed utilizing the enzymatic biosensor to explore the feasibility of target biomarker detection from clinical extracts of different biofluids for wound monitoring. Biosensor response evaluation from the extracts of human wound exudate, and those obtained from perilesional and healthy skin, provided an average recovery between 107 % and 110 % with a deviation within (+/-) 6 %. Gradual decrease in response (10-20 %) was noted in detection from extracts further away from injury site. Increased accumulation of biofluids on the sensor surface was studied to explore sensor response stability as a function of sample volume. With a broad linear range of detection (0.1 nM – 7.3 mM) and detection limits lower than the physiological concentrations, this study has assessed the viability of stable wound monitoring under physiologically relevant conditions on a wearable platform

    Naming and discovery in networks : architecture and economics

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    In less than three decades, the Internet was transformed from a research network available to the academic community into an international communication infrastructure. Despite its tremendous success, there is a growing consensus in the research community that the Internet has architectural limitations that need to be addressed in a effort to design a future Internet. Among the main technical limitations are the lack of mobility support, and the lack of security and trust. The Internet, and particularly TCP/IP, identifies endpoints using a location/routing identifier, the IP address. Coupling the endpoint identifier to the location identifier hinders mobility and poorly identifies the actual endpoint. On the other hand, the lack of security has been attributed to limitations in both the network and the endpoint. Authentication for example is one of the main concerns in the architecture and is hard to implement partly due to lack of identity support. The general problem that this dissertation is concerned with is that of designing a future Internet. Towards this end, we focus on two specific sub-problems. The first problem is the lack of a framework for thinking about architectures and their design implications. It was obvious after surveying the literature that the majority of the architectural work remains idiosyncratic and descriptions of network architectures are mostly idiomatic. This has led to the overloading of architectural terms, and to the emergence of a large body of network architecture proposals with no clear understanding of their cross similarities, compatibility points, their unique properties, and architectural performance and soundness. On the other hand, the second problem concerns the limitations of traditional naming and discovery schemes in terms of service differentiation and economic incentives. One of the recurring themes in the community is the need to separate an entity\u27s identifier from its locator to enhance mobility and security. Separation of identifier and locator is a widely accepted design principle for a future Internet. Separation however requires a process to translate from the identifier to the locator when discovering a network path to some identified entity. We refer to this process as identifier-based discovery, or simply discovery, and we recognize two limitations that are inherent in the design of traditional discovery schemes. The first limitation is the homogeneity of the service where all entities are assumed to have the same discovery performance requirements. The second limitation is the inherent incentive mismatch as it relates to sharing the cost of discovery. This dissertation addresses both subproblems, the architectural framework as well as the naming and discovery limitations

    Autocatalytic metallization of fabrics using Si ink, for biosensors, batteries and energy harvesting

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    Commercially available metal inks are mainly designed for planar substrates (for example, polyethylene terephthalate foils or ceramics), and they contain hydrophobic polymer binders that fill the pores in fabrics when printed, thus resulting in hydrophobic electrodes. Here, a low‐cost binder‐free method for the metallization of woven and nonwoven fabrics is presented that preserves the 3D structure and hydrophilicity of the substrate. Metals such as Au, Ag, and Pt are grown autocatalytically, using metal salts, inside the fibrous network of fabrics at room temperature in a two‐step process, with a water‐based silicon particle ink acting as precursor. Using this method, (patterned) metallized fabrics are being enabled to be produced with low electrical resistance (less than 3.5 Ω sq−1). In addition to fabrics, the method is also compatible with other 3D hydrophilic substrates such as nitrocellulose membranes. The versatility of this method is demonstrated by producing coil antennas for wireless energy harvesting, Ag–Zn batteries for energy storage, electrochemical biosensors for the detection of DNA/proteins, and as a substrate for optical sensing by surface enhanced Raman spectroscopy. In the future, this method of metallization may pave the way for new classes of high‐performance devices using low‐cost fabrics
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