84 research outputs found

    Review on PAR Reduction Techniques for MIMO-OFDM

    Get PDF
    Orthogonal Frequency Division Multiplexing (OFDM) is a multicarrier communication scheme Plays a prominent role in wireless communication technology as multicarrier transmission scheme. The combination of multiple-input multiple-output (MIMO) technology with orthogonal frequency division multiplexing is an attractive solution for next generation of wireless network. However, practical implementation of OFDM introduced a major drawback known as high Peak-to-Average Power ratio (PAR). This paper inclusion detail of peak-to-Average Power ratio and its reduction techniques

    Maximizing Throughput of Decentralized Wireless Sensor Network Using Reinforcement Learning

    Get PDF
    A reinforcement learning algorithm with the aim to increase the throughput of a Wireless Sensor Network (WSN) and decrease latency in a decentralized manner. WSNs are collections of sensor nodes that gather environmental data, where the main challenges are the limited power supply of nodes and the need for decentralized control. A distributed resource allocation algorithm for cellular MIMO networks by adopting a Reinforcement Learning (RL) approach. We use RL methods which employ Growing Self Organizing Maps to deal with the huge and continuous problem space. The goal of the algorithm is to maximize the network throughput in a fair manner. Indeed, the algorithm maximizes the throughput until fairness violation does not exceed an adjustable threshold

    Performance of a hydromagnetic squeeze film on a rough circular step bearing: a comparision of different porous structures

    Get PDF
    This investigation deals with a comparative analysis of the impact of spongy structure based on the model of Kozeny-Carman and Irmay on a hydromagnetic squeeze film in a rough circular step bearing. Christensen and Tonder’s stochastic averaging process has been utilized to determine the role of an arbitrary transverse surface irregularity. The distribution of the pressure in the bearing is obtained by solving the concerned generalised stochastically averaged equation of Reynolds’ with appropriate boundary conditions. The outcomes show that increasing values of magnetization results in an augmented load. The impact of the surface irregularity (transverse) has been found to be adverse. In addition, the negative effect of the surface irregularity and porosity can be minimised by the positive impact of magnetization, at least in the case of the globular sphere model of Kozeny-Carman. Furthermore, the lower strength of the magnetic field results in an approximately similar performance for both these models. This study offers the possibility that the Kozeny-Carman model could be deployed in comparison with Irmay’s model

    A Novel Simulation Based Methodology for the Congestion Control in ATM Networks

    Get PDF
    © ASEE 2009In this project, we use the OPNET simulation tool for modeling and analysis of packet data networks. Our project is mainly focused on the performance analysis of Asynchronous transfer mode (ATM) networks. Specifically, in this project, we simulate two types of high-performance networks namely, Fiber Distributed Data Interface (FDDI) and Asynchronous Transfer Mode (ATM). In the first type of network, we examine the performance of the FDDI protocol by varying network parameters in two network configurations. In the second type, we build a simple ATM network model and measure its performance under various ATM service categories. Finally, we develop an OPNET process model for leaky bucket congestion control algorithm and examine its performance and its relative effect on the traffic patterns (loss and burst size) in an ATM network. Our simulation results show that the ATM network has longer response time than FDDI. On the other hand, it shows that for both token ring and MAC delay, ATM is shorter than FDDI

    Isolation and Characterization of Bacterial Endophytes from Lycopersicon esculentum Plant and their Plant Growth Promoting Characteristics

    Get PDF
    The study was designed to isolate and characterize bacterial endophytes from root and stem of Lycopersicon esculentum plant which was collected form different region of Gujarat. Total 18 isolates of endophytic bacteria were selected in which, all the endophytic bacteria produced one or the other different characteristics involved in plant growth promotion. They either produced phytohormones like indole acetic acid, siderophore, protease, pectinase, organic acid showed antifungal activity, chromium tolerance and solubilized phosphate. Four of the strains among the 18 showed maximum positive results of plant growth promoting regulators (PGPR) test and among them best probable isolate was selected and thus its 16SrDNA was amplified and sequenced. Only HR7 endophyte of tomato turned out to be Pseudomonas aeruginosa. It’s a gram negative coccobacili, sporeforming motile bacilli and show maximum PGPR activity. The results of our present studies indicated that above strains might be endophytic and therefore, were associated with the plant growth. Keywords: Lycopersicon esculentum; endophytic bacteria; PGPR; IAA; 16SrDNA DOI: http://dx.doi.org/10.3126/njb.v2i1.5679   Nepal Journal of Biotechnology Jan.2012, Vol.2(1): 37-5

    Adverse drug reaction monitoring on antiretroviral therapy in human immunodeficiency virus patients in a tertiary care hospital

    Get PDF
    Background: The aim of current study was to assess the pattern of adverse drug reactions (ADRs) in patients receiving antiretroviral (ARV) therapy.Methods: A prospective, observational study was carried out for duration of 15 months. Clinical and treatment data were collected from patients, who underwent ARV therapy during the study period. CDSCO forms were used to record the ADRs. Causality, severity and preventability were assessed by suitable scales.Result: Out of 216 patients 165 (76%) patients develop ADRs. Total of 274 ADRs were noted among 165 patients (1.66 ADR/patient). Out of them 100 (60.60%) were males and 65 (39.39%) were females. The most common ADR was gastrointestinal disorders (83, 30.29%). The most numbers of ADRs were observed in ZLN (Zidovudine + Lamivudine + Nevirapine) regimen (54%) followed by SLN (Stavudine + Lamivudine + Nevirapine) regimen (26%). According to WHO causality assessment scale most ADRs were possible (236, 86.13%). Hartwig and Siegel severity scale show 243 (88.69%) ADRs were moderate. Schumock and Thornton scale show all, ADRs were “not preventable.”Conclusion: Early detection of drug toxicity helps to treat the patient and modify the drug regimen to minimize toxic effects

    Detailed Performance Loss Analysis of Silicon Solar Cells using High-Throughput Metrology Methods

    Full text link
    In this work, novel, high-throughput metrology methods are used to perform a detailed performance loss analysis of approximately 400 industrial crystalline silicon solar cells, all coming from the same production line. The characterization sequence includes a non-destructive transfer length method (TLM) measurement technique featuring circular TLM structures hidden within the busbar region of the cells. It also includes a very fast external quantum efficiency and reflectance measurement technique. More traditional measurements, like illuminated current-voltage, Suns-VOC, and photoluminescence imaging are also used to carry out the loss analysis. The variance of the individual loss parameters and their impact on cell performance are investigated and quantified for this large group of industrial solar cells. Some important correlations between the measured loss parameters are found. The nature of these distributions and correlations provide important insights about loss mechanisms in a cell and help prioritize efforts to optimize the performance of the production line.Comment: 5 pages, 6 figures, conferenc

    Patient-derived Organoid Pharmacotyping is a Clinically Tractable Strategy for Precision Medicine in Pancreatic Cancer

    Get PDF
    Objective: PDAC patients who undergo surgical resection and receive effective chemotherapy have the best chance of long-term survival. Unfortunately, we lack predictive biomarkers to guide optimal systemic treatment. Ex-vivo generation of PDO for pharmacotyping may serve as predictive biomarkers in PDAC. The goal of the current study was to demonstrate the clinical feasibility of a PDO-guided precision medicine framework of care. Methods: PDO cultures were established from surgical specimens and endoscopic biopsies, expanded in Matrigel, and used for high-throughput drug testing (pharmacotyping). Efficacy of standard-of-care chemotherapeutics was assessed by measuring cell viability after drug exposure. Results: A framework for rapid pharmacotyping of PDOs was established across a multi-institutional consortium of academic medical centers. Specimens obtained remotely and shipped to a central biorepository maintain viability and allowed generation of PDOs with 77% success. Early cultures maintain the clonal heterogeneity seen in PDAC with similar phenotypes (cystic-solid). Late cultures exhibit a dominant clone with a pharmacotyping profile similar to early passages. The biomass required for accurate pharmacotyping can be minimized by leveraging a high-throughput technology. Twenty-nine cultures were pharmacotyped to derive a population distribution of chemotherapeutic sensitivity at our center. Pharmacotyping rapidly-expanded PDOs was completed in a median of 48 (range 18-102) days. Conclusions: Rapid development of PDOs from patients undergoing surgery for PDAC is eminently feasible within the perioperative recovery period, enabling the potential for pharmacotyping to guide postoperative adjuvant chemotherapeutic selection. Studies validating PDOs as a promising predictive biomarker are ongoing.Peer reviewe

    Global incidence, prevalence, years lived with disability (YLDs), disability-adjusted life-years (DALYs), and healthy life expectancy (HALE) for 371 diseases and injuries in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

    Get PDF
    Background: Detailed, comprehensive, and timely reporting on population health by underlying causes of disability and premature death is crucial to understanding and responding to complex patterns of disease and injury burden over time and across age groups, sexes, and locations. The availability of disease burden estimates can promote evidence-based interventions that enable public health researchers, policy makers, and other professionals to implement strategies that can mitigate diseases. It can also facilitate more rigorous monitoring of progress towards national and international health targets, such as the Sustainable Development Goals. For three decades, the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) has filled that need. A global network of collaborators contributed to the production of GBD 2021 by providing, reviewing, and analysing all available data. GBD estimates are updated routinely with additional data and refined analytical methods. GBD 2021 presents, for the first time, estimates of health loss due to the COVID-19 pandemic. Methods: The GBD 2021 disease and injury burden analysis estimated years lived with disability (YLDs), years of life lost (YLLs), disability-adjusted life-years (DALYs), and healthy life expectancy (HALE) for 371 diseases and injuries using 100 983 data sources. Data were extracted from vital registration systems, verbal autopsies, censuses, household surveys, disease-specific registries, health service contact data, and other sources. YLDs were calculated by multiplying cause-age-sex-location-year-specific prevalence of sequelae by their respective disability weights, for each disease and injury. YLLs were calculated by multiplying cause-age-sex-location-year-specific deaths by the standard life expectancy at the age that death occurred. DALYs were calculated by summing YLDs and YLLs. HALE estimates were produced using YLDs per capita and age-specific mortality rates by location, age, sex, year, and cause. 95% uncertainty intervals (UIs) were generated for all final estimates as the 2·5th and 97·5th percentiles values of 500 draws. Uncertainty was propagated at each step of the estimation process. Counts and age-standardised rates were calculated globally, for seven super-regions, 21 regions, 204 countries and territories (including 21 countries with subnational locations), and 811 subnational locations, from 1990 to 2021. Here we report data for 2010 to 2021 to highlight trends in disease burden over the past decade and through the first 2 years of the COVID-19 pandemic. Findings: Global DALYs increased from 2·63 billion (95% UI 2·44–2·85) in 2010 to 2·88 billion (2·64–3·15) in 2021 for all causes combined. Much of this increase in the number of DALYs was due to population growth and ageing, as indicated by a decrease in global age-standardised all-cause DALY rates of 14·2% (95% UI 10·7–17·3) between 2010 and 2019. Notably, however, this decrease in rates reversed during the first 2 years of the COVID-19 pandemic, with increases in global age-standardised all-cause DALY rates since 2019 of 4·1% (1·8–6·3) in 2020 and 7·2% (4·7–10·0) in 2021. In 2021, COVID-19 was the leading cause of DALYs globally (212·0 million [198·0–234·5] DALYs), followed by ischaemic heart disease (188·3 million [176·7–198·3]), neonatal disorders (186·3 million [162·3–214·9]), and stroke (160·4 million [148·0–171·7]). However, notable health gains were seen among other leading communicable, maternal, neonatal, and nutritional (CMNN) diseases. Globally between 2010 and 2021, the age-standardised DALY rates for HIV/AIDS decreased by 47·8% (43·3–51·7) and for diarrhoeal diseases decreased by 47·0% (39·9–52·9). Non-communicable diseases contributed 1·73 billion (95% UI 1·54–1·94) DALYs in 2021, with a decrease in age-standardised DALY rates since 2010 of 6·4% (95% UI 3·5–9·5). Between 2010 and 2021, among the 25 leading Level 3 causes, age-standardised DALY rates increased most substantially for anxiety disorders (16·7% [14·0–19·8]), depressive disorders (16·4% [11·9–21·3]), and diabetes (14·0% [10·0–17·4]). Age-standardised DALY rates due to injuries decreased globally by 24·0% (20·7–27·2) between 2010 and 2021, although improvements were not uniform across locations, ages, and sexes. Globally, HALE at birth improved slightly, from 61·3 years (58·6–63·6) in 2010 to 62·2 years (59·4–64·7) in 2021. However, despite this overall increase, HALE decreased by 2·2% (1·6–2·9) between 2019 and 2021. Interpretation: Putting the COVID-19 pandemic in the context of a mutually exclusive and collectively exhaustive list of causes of health loss is crucial to understanding its impact and ensuring that health funding and policy address needs at both local and global levels through cost-effective and evidence-based interventions. A global epidemiological transition remains underway. Our findings suggest that prioritising non-communicable disease prevention and treatment policies, as well as strengthening health systems, continues to be crucially important. The progress on reducing the burden of CMNN diseases must not stall; although global trends are improving, the burden of CMNN diseases remains unacceptably high. Evidence-based interventions will help save the lives of young children and mothers and improve the overall health and economic conditions of societies across the world. Governments and multilateral organisations should prioritise pandemic preparedness planning alongside efforts to reduce the burden of diseases and injuries that will strain resources in the coming decades. Funding: Bill & Melinda Gates Foundation
    corecore