558 research outputs found

    Adaptive wavelet neural network for wind speed and solar power forecasting for Italian data

    Get PDF
    Conventional energy sources are nowadays exhausting and that is the reason why renewable energy sources are so important in current situation. In addition renewables are non-pollutant and freely available in nature. Wind and solar power are the fastest growing renewable energy sources for the past few decades, especially according to the 2020 energy strategy in Europe. They are having enough scope in the power market. The main problem with these renewable energy sources is their unpredictability and, in this context, issues like power quality and power system grid stability arise. In order to limit the effects of these issues, power market needs information about power generation at least one day in advance. This problem can be addressed by proper forecasting of Renewable Energy Sources (RES). Forecasting helps to schedule power properly. Adaptive Wavelet Neural Network (AWNN), a technique already assessed in literature for wind speed forecasting, is here applied also to solar power prediction. After forecasting each individual signal, the Mean Absolute Percentage Error (MAPE) is calculated in different time horizons

    Allelic richness and diversity in global composite collection and reference sets in chickpea (Cicer arietinum L.)

    Get PDF
    Chickpea is the fourth largest grain legume crop globally. A composite collection of 3000 accessions was formed and genotyped using 50 SSR markers. The accessions were also field evaluated for seven qualitative traits. Analysis of 48 SSR markers data on 2915 accessions detected 1683 alleles, of which 935 were rare and 748 common. Gene diversity varied from 0.533 to 0.975. Kabuli chickpea as a group were genetically more diverse than other seed types. Several group-specific unique alleles were detected: 104 in Kabuli, 297 in desi, and 69 in wild Cicer; 114 each in West Asia and Mediterranean, 117 in South and South East Asia, and 10 in African region accessions. A genotype-based reference set captured 1315 alleles compared to 1237 alleles in the reference set based on qualitative traits or 1354 alleles based on SSRs and qualitative traits data. The relative usefulness of these reference sets in chickpea breeding and genomics studies are being further investigated

    Multiwavelength Study on Solar and Interplanetary Origins of the Strongest Geomagnetic Storm of Solar Cycle 23

    Full text link
    We study the solar sources of an intense geomagnetic storm of solar cycle 23 that occurred on 20 November 2003, based on ground- and space-based multiwavelength observations. The coronal mass ejections (CMEs) responsible for the above geomagnetic storm originated from the super-active region NOAA 10501. We investigate the H-alpha observations of the flare events made with a 15 cm solar tower telescope at ARIES, Nainital, India. The propagation characteristics of the CMEs have been derived from the three-dimensional images of the solar wind (i.e., density and speed) obtained from the interplanetary scintillation data, supplemented with other ground- and space-based measurements. The TRACE, SXI and H-alpha observations revealed two successive ejections (of speeds ~350 and ~100 km/s), originating from the same filament channel, which were associated with two high speed CMEs (~1223 and ~1660 km/s, respectively). These two ejections generated propagating fast shock waves (i.e., fast drifting type II radio bursts) in the corona. The interaction of these CMEs along the Sun-Earth line has led to the severity of the storm. According to our investigation, the interplanetary medium consisted of two merging magnetic clouds (MCs) that preserved their identity during their propagation. These magnetic clouds made the interplanetary magnetic field (IMF) southward for a long time, which reconnected with the geomagnetic field, resulting the super-storm (Dst_peak=-472 nT) on the Earth.Comment: 24 pages, 16 figures, Accepted for publication in Solar Physic

    Projected HIV and Bacterial Sexually Transmitted Infection Incidence following COVID-19-Related Sexual Distancing and Clinical Service Interruption

    Get PDF
    Background: The global COVID-19 pandemic has the potential to indirectly impact transmission dynamics and prevention of HIV and other sexually transmitted infections (STI). It is unknown what combined impact reductions in sexual activity and interruptions in HIV/STI services will have on HIV/STI epidemic trajectories. Methods: We adapted a model of HIV, gonorrhea, and chlamydia for a population of approximately 103 000 men who have sex with men (MSM) in the Atlanta area. Model scenarios varied the timing, overlap, and relative extent of COVID-19-related sexual distancing and service interruption within 4 service categories (HIV screening, preexposure prophylaxis, antiretroviral therapy, and STI treatment). Results: A 50% relative decrease in sexual partnerships and interruption of all clinical services, both lasting 18 months, would generally offset each other for HIV (total 5-year population impact for Atlanta MSM,-227 cases), but have net protective effect for STIs (-23 800 cases). If distancing lasted only 3 months but service interruption lasted 18 months, the total 5-year population impact would be an additional 890 HIV cases and 57 500 STI cases. Conclusions: Immediate action to limit the impact of service interruptions is needed to address the indirect effects of the global COVID-19 pandemic on the HIV/STI epidemic

    Mode-locked thulium ytterbium co-doped fiber laser with graphene oxide paper saturable absorber

    Get PDF
    A mode-locked thulium ytterbium co-doped fiber laser (TYDFL) is proposed and demonstrated by using a commercial graphene oxide (GO) paper as saturable absorber (SA). The GO paper is sandwiched between two fiber ferrules and incorporates a ring laser cavity to generate soliton pulse train operating at 1942.0 nm at a threshold multimode pump power as low as 1.8 W. The mode-locked TYDFL has a repetition rate of 22.32 MHz and the calculated pulse width of 1.1 ns. Even though the SA has a low damage threshold, the easy fabrication of GO paper should promote its potential application in ultrafast photonics

    Simultaneous analysis of frequency and voltage control of the interconnected hybrid power system in presence of FACTS devices and demand response scheme

    Get PDF
    This work confers the simultaneous analysis of voltage and frequency control of the 3-area interconnected hybrid power system (IHPS) consisting of parabolic-trough solar power system (PSP), wind power system (WPS) and dish-stirling solar power system (DSP) under the paradigm of microgrid. The speculated result of the IHPS is presented and analyzed considering real and reactive power as the function of both voltage and frequency. 9The proposed IHPS under investigation has been mathematically modeled for direct coupling like active power-frequency and reactive power-voltage relationships and cross coupling like active power-voltage and reactive power-frequency? relationships. The system responses under different operating conditions have been investigated to see the cross-coupling behavior of the proposed IHPS in the presence of voltage compensating devices like dynamic voltage restorer (DVR) and Static Synchronous Compensator (STATCOM). Further, Demand Response Scheme (DRS) as a frequency control strategy has been considered to enhance the system stability. System responses have been critically analyzed under Mine Blast Algorithm (MBA) based proportional-integral-derivative (PID) controllersThis work was made possible by NPRP grant # [ 13S-0108-20008 ] from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the authors".Scopu

    A Brief History, Status, and Perspective of Modified Oligonucleotides for Chemotherapeutic Applications

    Full text link
    The advent of rapid and efficient methods of oligonucleotide synthesis has allowed the design of modified oligonucleotides that are complementary to specific nucleotide sequences in mRNA targets. Such modified oligonucleotides can be used to disrupt the flow of genetic information from transcribed mRNAs to proteins. This antisense strategy has been used to develop therapeutic oligonucleotides against cancer and various infectious diseases in humans. This overview reports recent advances in the application of oligonucleotides as drug candidates, describes the relationship between oligonucleotide modifications and their therapeutic profiles, and provides general guidelines for enhancing oligonucleotide drug properties.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143788/1/cpnc0401.pd
    corecore