929 research outputs found

    SIMPLE: Stable Increased-throughput Multi-hop Protocol for Link Efficiency in Wireless Body Area Networks

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    In this work, we propose a reliable, power efficient and high throughput routing protocol for Wireless Body Area Networks (WBANs). We use multi-hop topology to achieve minimum energy consumption and longer network lifetime. We propose a cost function to select parent node or forwarder. Proposed cost function selects a parent node which has high residual energy and minimum distance to sink. Residual energy parameter balances the energy consumption among the sensor nodes while distance parameter ensures successful packet delivery to sink. Simulation results show that our proposed protocol maximize the network stability period and nodes stay alive for longer period. Longer stability period contributes high packet delivery to sink which is major interest for continuous patient monitoring.Comment: IEEE 8th International Conference on Broadband and Wireless Computing, Communication and Applications (BWCCA'13), Compiegne, Franc

    M-GEAR: Gateway-Based Energy-Aware Multi-Hop Routing Protocol for WSNs

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    In this research work, we advise gateway based energy-efficient routing protocol (M-GEAR) for Wireless Sensor Networks (WSNs). We divide the sensor nodes into four logical regions on the basis of their location in the sensing field. We install Base Station (BS) out of the sensing area and a gateway node at the centre of the sensing area. If the distance of a sensor node from BS or gateway is less than predefined distance threshold, the node uses direct communication. We divide the rest of nodes into two equal regions whose distance is beyond the threshold distance. We select cluster heads (CHs)in each region which are independent of the other region. These CHs are selected on the basis of a probability. We compare performance of our protocol with LEACH (Low Energy Adaptive Clustering Hierarchy). Performance analysis and compared statistic results show that our proposed protocol perform well in terms of energy consumption and network lifetime.Comment: IEEE 8th International Conference on Broadband and Wireless Computing, Communication and Applications (BWCCA'13), Compiegne, Franc

    Sorptivity of self-compacting concrete containing fly ash and silica fume

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    This paper presents the surface water absorption of self-compacting concrete (SCC) containing fly ash and silica fume using sorptivity test. Ordinary Portland cement was partially replaced by various combinations of fly ash and silica fume. Test results show that the presence of fly ash and silica fume significantly reduce the surface water absorption of self-compacting concrete at a water-binder ratio of 0.38. When only fly ash is used to partially replace Ordinary Portland cement, a more noticeable reduction in sorptivity is found when the fly ash content is greater than 20%

    Peristaltic Transport of a Rheological Fluid: Model for Movement of Food Bolus Through Esophagus

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    Fluid mechanical peristaltic transport through esophagus has been of concern in the paper. A mathematical model has been developed with an aim to study the peristaltic transport of a rheological fluid for arbitrary wave shapes and tube lengths. The Ostwald-de Waele power law of viscous fluid is considered here to depict the non-Newtonian behaviour of the fluid. The model is formulated and analyzed with the specific aim of exploring some important information concerning the movement of food bolus through the esophagus. The analysis has been carried out by using lubrication theory. The study is particularly suitable for cases where the Reynolds number is small. The esophagus is treated as a circular tube through which the transport of food bolus takes places by periodic contraction of the esophageal wall. Variation of different variables concerned with the transport phenomena such as pressure, flow velocity, particle trajectory and reflux are investigated for a single wave as well as for a train of periodic peristaltic waves. Locally variable pressure is seen to be highly sensitive to the flow index `n'. The study clearly shows that continuous fluid transport for Newtonian/rheological fluids by wave train propagation is much more effective than widely spaced single wave propagation in the case of peristaltic movement of food bolus in the esophagus.Comment: Accepted for publication in Applied Mathematics and Mechanics (AMM), Springe

    Blockchain Technology for Enhancing Traceability and Efficiency in Automobile Supply Chain—A Case Study

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    A robust traceability system would help organizations in inventory optimization reduce lead time and improve customer service and quality which further enables the organizations to be a leader in their industry sector. This research study analyzes the challenges faced by the automotive industry in its supply chain operations. Further, the traceability issues and waiting time at different nodes of the supply chain are considered to be priority issues that affect the overall supply chain efficiency in the automotive supply chain. After studying the existing blockchain architectures and their implementation methodology, this study proposes a new blockchain-based architecture to improve traceability and reduce waiting time for the automotive supply chain. A hyper ledger fabric-based blockchain architecture is developed to track the ownership transfers in inbound and outbound logistics. The simulation results of the proposed hyper ledger fabric-based blockchain architecture show that there is an improvement in the traceability of items at different nodes of the supply chain that enhances the Inventory Quality Ratio (IQR) and the mean waiting time is reduced at the factory, wholesaler, and retailer, which thereby improves the overall supply chain efficiency. The blockchain embedded supply chain is more capable to eliminate the risks and uncertainties associated with the automotive supply chain. The benefits of adopting blockchain technology in the automotive supply chain are also described. The developed blockchain-based framework is capable to get more visibility into goods movement and inventory status in automotive supply chains

    Boundary layer flow of nanofluid over an exponentially stretching surface

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    The steady boundary layer flow of nanofluid over an exponential stretching surface is investigated analytically. The transport equations include the effects of Brownian motion parameter and thermophoresis parameter. The highly nonlinear coupled partial differential equations are simplified with the help of suitable similarity transformations. The reduced equations are then solved analytically with the help of homotopy analysis method (HAM). The convergence of HAM solutions are obtained by plotting h-curve. The expressions for velocity, temperature and nanoparticle volume fraction are computed for some values of the parameters namely, suction injection parameter α, Lewis number Le, the Brownian motion parameter Nb and thermophoresis parameter Nt

    Synthesis and Thermal Degradation Studies of Melamine Formaldehyde Resins

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    Melamine formaldehyde (MF) resins have been synthesized at different reaction temperature and pH values. Different molar ratios of melamine and formaldehyde were used to synthesize the corresponding resins. The prepared resin samples were characterized by using molecular weight determination viscometry and thermogravimetric analysis (TGA). The maximum percentage of solid content (69.7%) was obtained at pH 8.5 and 75°C temperature. The molecular weight of MF resin was increased with an increase of melamine monomer concentration. The highest residual weight 14.125 wt.% was obtained with sample 10

    Epoxidación de ésteres metílicos derivados del aceite de Jatropha: Optimización del estudio

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    The optimization of the epoxidation reaction of methyl esters obtained from Jatropha oil was appraised. Response surface methodology (RSM) based on a central composite rotatable design (CCRD) was employed for the experimental design. Four reaction variables namely hydrogen peroxide/ C=C mole ratio, formic acid/C=C mole ratio, reaction temperature and reaction time were evaluated. The optimum epoxidation conditions calculated by the quadratic model were 3.12 moles of hydrogen peroxide/C=C moles, 0.96 moles of formic acid/C=C moles, a reaction temperature of 70.0 °C and a reaction time of 277 minutes. A reaction optimized by the proposed process parameters provided a yield of 92.89 ± 1.29 wt.% with relatively improved reaction time. Hydrogen peroxide concentration and reaction temperature were found to be the most significant variables while reaction temperature and hydrogen peroxide showed strong interactions. The epoxidized methyl esters were analyzed using FT-IR, 1H NMR and 13C NMR techniques. This study suggested relatively higher molar ratio of formic acid required than was proposed in the literature.Se ha evaluado la optimización de la reacción de epoxidación de ésteres metílicos obtenidos a partir de aceite de Jatropha. Se ha empleado para el diseño experimental una metodología de superficie de respuesta (RSM), basada en un diseño compuesto central giratorio (CCRD). Cuatro variables de la reacción fueron evaluadas: relación molar peróxido de hidrógeno/C=C, relación molar ácido fórmico/C=C, temperatura de reacción y tiempo de reacción. Las condiciones óptimas de epoxidación calculadas por el modelo cuadrático fueron 3.12 moles de peróxido de hidrógeno/C=C moles, 0.96 moles de ácido fórmico/C=C moles, una temperatura de reacción de 70.0 °C y un tiempo de reacción de 277 minutos. Una reacción optimizada mediante los parámetros propuestos del proceso proporciona un rendimiento de 92.89 ± 1.29% en peso con un tiempo de reacción relativamente mejorado. La concentración de peróxido de hidrógeno y la temperatura de la reacción fueron las variables más significativas, además la temperatura de la reacción y la concentración de peróxido de hidrógeno mostraron fuertes interacciones. Los ésteres metílicos epoxidados se analizaron mediante FT-IR, 1H RMN y RMN de 13C. Este estudio indica que se requiere una proporción molar relativamente mayor de ácido fórmico que la propuesta en la literatura
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