103 research outputs found

    Effect of Thermal Radiation, Dissipation and Chemical Reaction on Mixed Convective Heat and Mass Transfer Flow Past a Stretching Sheet with Hall Effects in Slip Flow Regime

    Get PDF
    The aim of this analysis is to discuss the combined influence of chemical reaction, dissipation  on hydromagnetic mixed convective heat and mass transfer flow of a viscous electrically conducting fluid past a stretching sheet in the presence of non-uniform heat source and Hall effects. The equations governing the flow, heat and mass transfer have been solved numerically by using  Runge-Kutta fourth order technique together with the shooting technique. The velocity, temperature and concentration have been analyzed. The rate of heat and mass transfer on the plate has been evaluated numerically for different parametric variations. Keywords: Hall Currents; Heat & Mass Transfer; Thermal Radiation; Dissipation, Non-Uniform Heat Source; Soret and Dufour effects; Stretching sheet; Chemical reaction.

    Non-Darcy Convective Heat and Mass Transfer Flow in a Vertical Channel

    Get PDF
    We make an attempt to investigate non-Darcy convective heat and Mass transfer flow of a viscous chemically reacting fluid in a vertical channel .The Brinkman Forchheimer extended Darcy equations are used in the governing linear momentum equation, which are solve numerically by using  Galerkin finite element technique. The velocity, temperature, concentration, shear stress and rate of Heat and Mass transfer are evaluated numerically for different variations .It is noticed that the temperature and concentration reduce while the velocity increases in the degenerating chemical reaction ( g>0) while in the generating case(g<0), they reduce in the entire flow region The rate of heat and mass transfer reduce and the skin friction increases on the walls with increase in g>0, while a reversed effect is noticed with  g<0. Keywords: Non-Darcy Flow, Porous Medium, Chemical reaction, Vertical Channe

    Design and Performance Analysis of Low Latency Routing Algorithm based NoC for MPSoC

    Get PDF
    The Network on Chip is appropriate where System-on-Chip technology is scalable and adaptable. The Network on Chip is a new communication architecture with a number of benefits, including scalability, flexibility, and reusability, for applications built on Multiprocessor System on a Chip (MPSoC). However, the design of efficient NoC fabric with high performance is critically complex because of its architectural parameters. Identifying a suitable scheduling algorithm to resolve arbitration among ports to obtain high-speed data transfer in the router is one of the most significant phases while designing a Network on chip based Multiprocessor System on a Chip. Low latency, throughput, space utilization, energy consumption, and reliability for Network on chip fabric are all determined by the router. The performance of the NoC system is hampered by the deadlock issues that plague conventional routing algorithms. This work develops a novel routing algorithm to address the deadlock problem. In this paper, a deterministic shortest path deadlock-free routing method is developed based on the analysis of the Turn Model. In the 2D-mesh structure, the algorithm uses separate routing methods for the odd and even columns. This minimizes the number of paths for a single channel, congestion, and latency. Two test scenarios—one with and one without a load test—were used to evaluate the proposed model. For a zero-load network, three clock cycles are utilized to transfer the packets. For the load network, five clocks are utilized to transfer the packets. The latency is measured for both cases without load and with load test and the corresponding latency is 3ns and 7ns respectively.The proposed method has an 18.57Mbps throughput.  The area and power utilization for the proposed method are 69% (IO utilization) and 0.128W respectively. In order to validate the proposed method, the latency is compared with existing work and 50% latency is reduced both with and without congestion load

    Sorghum: A Multipurpose Bioenergy Crop

    Get PDF
    Bioethanol and biodiesel produced from renewable energy sources are gaining importance in light of volatile fossil fuel prices, depleting oil reserves, and increasing greenhouse effects associated with the use of fossil fuels. Among several alternative renewable energy sources, energy derived from plant biomass is found to be promising and sustainable. Sorghum [Sorghum bicolor (L.) Moench] is a resilient dryland cereal crop with wide adaptation having high water, nutrient, and radiation use efficiencies. This crop is expected to enhance food, feed, fodder, and fuel security. Sweet sorghum is similar to grain sorghum but has the ability to accumulate sugars in the stalks without much reduction in grain production. Hence, it is used as a first-generation biofuel feedstock, where the grain and stalk sugars can be used for producing bioenergy, while energy sorghum or biomass sorghum is increasingly viewed as a potential feedstock for lignocellulosic biofuel production. Although the commercial use of sweet sorghum for bioethanol production has been demonstrated in China and India, the viability of large-scale lignocellulosic conversion of sorghum biomass to biofuels is yet to be demonstrated. This chapter dwells on sorghum feedstock characteristics, biofuel production models, sustainability indicators, and commercialization

    Statin pretreatment and risk of in-hospital atrial fibrillation among patients undergoing cardiac surgery: a collaborative meta-analysis of 11 randomized controlled trials

    Get PDF
    Aims Statin pretreatment in patients undergoing cardiac surgery is understood to prevent postoperative atrial fibrillation (AF). However, this is based on observational and limited randomized trial evidence, resulting in uncertainty about any genuine anti-arrhythmic benefits of these agents in this setting.We therefore aimed to quantify precisely the association between statin pretreatment and postoperative AF among patients undergoing cardiac surgery. Methods and results A detailed search of MEDLINE and PubMed databases (1st January 1996 to 31st July 2012)was conducted, followed by a review of the reference lists of published studies and correspondence with trial investigators to obtain individual– participant data for meta-analysis. Evidence was combined across prospective, randomized clinical trials that compared the risk of postoperative AF among individuals randomized to statin pretreatment or placebo/control medication before elective cardiac surgery. Postoperative AF was defined as episodes of AF lasting ≥5 min. Overall, 1105 participants from 11 trials were included; of them, 552 received statin therapy preoperatively. Postoperative AF occurred in 19% of these participants when compared with 36% of those not treated with statins (odds ratio 0.41, 95% confidence interval 0.31–0.54, P , 0.00001, using a random-effects model). Atrial fibrillation prevention by statin pretreatmentwas consistent across different subgroups. Conclusion Short-term statin pretreatment may reduce the risk of postoperative AF among patients undergoing cardiac surgery

    Tuberculosis chemotherapy: current drug delivery approaches

    Get PDF
    Tuberculosis is a leading killer of young adults worldwide and the global scourge of multi-drug resistant tuberculosis is reaching epidemic proportions. It is endemic in most developing countries and resurgent in developed and developing countries with high rates of human immunodeficiency virus infection. This article reviews the current situation in terms of drug delivery approaches for tuberculosis chemotherapy. A number of novel implant-, microparticulate-, and various other carrier-based drug delivery systems incorporating the principal anti-tuberculosis agents have been fabricated that either target the site of tuberculosis infection or reduce the dosing frequency with the aim of improving patient outcomes. These developments in drug delivery represent attractive options with significant merit, however, there is a requisite to manufacture an oral system, which directly addresses issues of unacceptable rifampicin bioavailability in fixed-dose combinations. This is fostered by the need to deliver medications to patients more efficiently and with fewer side effects, especially in developing countries. The fabrication of a polymeric once-daily oral multiparticulate fixed-dose combination of the principal anti-tuberculosis drugs, which attains segregated delivery of rifampicin and isoniazid for improved rifampicin bioavailability, could be a step in the right direction in addressing issues of treatment failure due to patient non-compliance

    Do smallholder farmer-led seed systems have the capacity to supply good-quality, fungal-free sorghum seed?

    Get PDF
    Local seed systems that are developed, managed and maintained by farmers are a fundamental practice in smallholder crop production, supporting more than 80% of farmers in sub-Saharan Africa and feeding more than 70% of its population. The resilience of such systems is under threat from poverty, climate change, drought, increased pests and diseases, over-promotion of modern crop varieties, change of lifestyles and restrictive seed policies. The system continues to be maligned as having inferior quality, yet few studies support this assertion. This study aims to fll this research gap by evaluating 60 sorghum seed samples collected from smallholder farmers in Uzumba-MarambaPfungwe and Chimanimani districts of Zimbabwe. We investigated the efect of farmer-led seed management practices (e.g. seed acquisition and seed storage practices) on farm-derived sorghum seed quality (moisture, germination and fungal incidences). We found farmers using diverse seed sources and seed storage practices. Seeds were typically of good quality in that their storage moisture content was low, their germination was high, and fungal incidences were low. Seed sourced from local markets, non-governmental organizations and other farmers had germination and moisture standards that met the sorghum certifcation standards in Zimbabwe. However, few samples obtained from the relatives and government failed to meet the germination and/or moisture certifcation standards. We detected low incidences of fungi (Aspergillus favus, Aspergillus niger, Curvularia lunata, Fusarium sp. and Penicillium sp.) in sorghum seed samples tested and in particular Fusarium sp., which is the most economic important fungus in sorghum production. We conclude that farmer-led seed systems have the capacity to supply seeds of good quality and recommend that such systems should be recognized and promoted to meet the ever-evolving needs of smallholder farmers in sub-Saharan Africa

    Use of anticoagulants and antiplatelet agents in stable outpatients with coronary artery disease and atrial fibrillation. International CLARIFY registry

    Get PDF
    corecore