563 research outputs found

    Decentralized P2P power trading mechanism for dynamic multi-energy microgrid groups based on priority matching

    Get PDF
    In order to promote the interaction among interconnected microgrids (MGs) with multiply distributed energy resources (DERs) to local energy utilization, a decentralized peer-to-peer (P2P) power trading mechanism based on priority matching is proposed. The priority indices are calculated based on scheduling results and quotations by an independent MG operator (IMO), which protect effectively the privacy and represent the bargaining willingness of MGs. According to the supply-demand ratio within a matching pair, each MG is permitted to update its quotation multi-times until the convergence or updated number limitation is reached. The clearing price of each pair is calculated by the mid-market rate (MMR) method. Because the imbalanced power is different with the autonomous scheduling in a MG at different dispatching time, the different power requirements of MGs results in the formation of the dynamic MG groups. The simulation results in an interconnected multi-microgrid system (IMMGS) with 4 MGs show the proposed decentralized P2P mechanism is reasonable and effective. (C) 2022 Published by Elsevier Ltd

    Multi-pipe string electromagnetic detection tool and its applications

    Get PDF
    The MID-K, a new kind of multi-pipe string detection tool is introduced. This tool provides a means of evaluating the condition of in-place pipe string, such as tubing and casino. It is capable of discriminating the defects of the inside and outside, and estimating the thickness of tubing and casing. It is accomplished by means of a low frequency eddy current to detect flaws on the inner surface and a magnetic flux leakage to inspect the full thickness. The measurement principle, the technology and applications are presented in this paper

    Breast cancer diagnosis using neural-based linear fusion strategies

    Get PDF
    Breast cancer is one of the leading causes of mortality among women, and the early diagnosis is of significant clinical importance. In this paper, we describe several linear fusion strategies, in particular the Majority Vote, Simple Average, Weighted Average, and Perceptron Average, which are used to combine a group of component multilayer perceptrons with optimal architecture for the classification of breast lesions. In our experiments, we utilize the criteria of mean squared error, absolute classification error, relative error ratio, and Receiver Operating Characteristic (ROC) curve to concretely evaluate and compare the performances of the four fusion strategies. The experimental results demonstrate that the Weighted Average and Perceptron Average strategies can achieve better diagnostic performance compared to the Majority Vote and Simple Average methods

    Neuropilin 1 is an entry factor that promotes EBV infection of nasopharyngeal epithelial cells

    Get PDF
    Epstein-Barr virus (EBV) is implicated as an aetiological factor in B lymphomas and nasopharyngeal carcinoma. The mechanisms of cell-free EBV infection of nasopharyngeal epithelial cells remain elusive. EBV glycoprotein B (gB) is the critical fusion protein for infection of both B and epithelial cells, and determines EBV susceptibility of non-B cells. Here we show that neuropilin 1 (NRP1) directly interacts with EBV gB 23-431. Either knockdown of NRP1 or pretreatment of EBV with soluble NRP1 suppresses EBV infection. Upregulation of NRP1 by overexpression or EGF treatment enhances EBV infection. However, NRP2, the homologue of NRP1, impairs EBV infection. EBV enters nasopharyngeal epithelial cells through NRP1-facilitated internalization and fusion, and through macropinocytosis and lipid raft-dependent endocytosis. NRP1 partially mediates EBV-activated EGFR/RAS/ERK signalling, and NRP1-dependent receptor tyrosine kinase (RTK) signalling promotes EBV infection. Taken together, NRP1 is identified as an EBV entry factor that cooperatively activates RTK signalling, which subsequently promotes EBV infection in nasopharyngeal epithelial cells. © 2014 Macmillan Publishers Limited. All rights reserved.published_or_final_versio

    Clinical characteristics of the autumn-winter type scrub typhus cases in south of Shandong province, northern China

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Before 1986, scrub typhus was only found endemic in southern China. Because human infections typically occur in the summer, it is called "summer type". During the autumn-winter period of 1986, a new type of scrub typhus was identified in Shandong and northern Jiangsu province of northern China. This newly recognized scrub typhus was subsequently reported in many areas of northern China and was then called "autumn-winter type". However, clinical characteristics of associated cases have not been reported.</p> <p>Methods</p> <p>From 1995 to 2006, all suspected scrub typhus cases in five township hospitals of Feixian county, Shandong province were enrolled. Indirect immunofluorescent assay (IFA) was used as confirmatory serodiagnosis test. Polymerase chain reaction (PCR) connected with restriction fragment length polymorphism (RFLP) and sequence analyses were used for genotyping of <it>O. tsutsugamushi </it>DNAs. Clinical symptoms and demography of confirmed cases were analyzed.</p> <p>Results</p> <p>A total of 480 scrub typhus cases were confirmed. The cases occurred every year exclusively between September and December with a peak occurrence in October. The case numbers were relatively higher in 1995, 1996, 1997, and 2000 than in other years. 57.9% of cases were in the group aged 21–50. More cases occurred in male (56%) than in female (44%). The predominant occupational group of the cases was farmers (85.0%). Farm work was reported the primary exposure to infection in 67.7% of cases. Fever, rash, and eschar were observed in 100.0%, 90.4%, and 88.5% of cases, respectively. Eschars formed frequently on or around umbilicus, abdomen areas, and front and back of waist (34.1%) in both genders. Normal results were observed in 88.7% (WBC counts), 84.5% (PLT counts), and 89.7% (RBC counts) of cases, respectively. Observations from the five hospitals were compared and no significant differences were found.</p> <p>Conclusion</p> <p>The autumn-winter type scrub typhus in northern China occurred exclusively from September to December with a peak occurrence in October, which was different from the summer type in southern China. In comparison with the summer type, complications associated with autumn-winter type scrub typhus were less severe, and abnormalities of routine hematological parameters were less obvious.</p

    An experimental investigation into resonance dry grinding of hardened steel and nickel alloys with element of MQL

    Get PDF
    Current policies on environmental issues put extra pressures on manufacturing processes to be resource efficient and eco-friendly. However, in grinding processes, large amounts of cutting fluids are used. These fluids are not environmental friendly thus require proper management before disposal with associated cost. Hence, this work sets to explore low-frequency vibration in grinding in order to improve coolant application in conventional grinding at the first stage with the aim to introduce this into high efficiency deep grinding (HEDG) at latter stage. An attempt is made to grind nickel alloys with minimum quantity lubricant (MQL) as oppose to flood cooling. To achieve this with minimum alterations to the machine tool, a piezo-driven workpiece holder was developed for surface grinding. This simple innovative workpiece holder allowed oscillating during actual grinding process. However, this paper presents the results of low-frequency oscillatory grinding in dry and near-dry conditions. The response of the machine tool spindle unit is presented alongside with the workpiece holder response. In this investigation, hardened steels and nickel alloys were ground with vibration assistance. The grinding forces are illustrated together with the surface finish. The wheel performance is given in terms of grinding ratio

    Observation of a ppb mass threshoud enhancement in \psi^\prime\to\pi^+\pi^-J/\psi(J/\psi\to\gamma p\bar{p}) decay

    Full text link
    The decay channel ψπ+πJ/ψ(J/ψγppˉ)\psi^\prime\to\pi^+\pi^-J/\psi(J/\psi\to\gamma p\bar{p}) is studied using a sample of 1.06×1081.06\times 10^8 ψ\psi^\prime events collected by the BESIII experiment at BEPCII. A strong enhancement at threshold is observed in the ppˉp\bar{p} invariant mass spectrum. The enhancement can be fit with an SS-wave Breit-Wigner resonance function with a resulting peak mass of M=186113+6(stat)26+7(syst)MeV/c2M=1861^{+6}_{-13} {\rm (stat)}^{+7}_{-26} {\rm (syst)} {\rm MeV/}c^2 and a narrow width that is Γ<38MeV/c2\Gamma<38 {\rm MeV/}c^2 at the 90% confidence level. These results are consistent with published BESII results. These mass and width values do not match with those of any known meson resonance.Comment: 5 pages, 3 figures, submitted to Chinese Physics

    Preparation and thermal conductivity of CuO nanofluid via a wet chemical method

    Get PDF
    In this article, a wet chemical method was developed to prepare stable CuO nanofluids. The influences of synthesis parameters, such as kinds and amounts of copper salts, reaction time, were studied. The thermal conductivities of CuO nanofluids were also investigated. The results showed that different copper salts resulted in different particle morphology. The concentration of copper acetate and reaction time affected the size and shape of clusters of primary nanoparticles. Nanofluids with different microstructures could be obtained by changing the synthesis parameters. The thermal conductivities of CuO nanofluids increased with the increase of particle loading

    Luminance, colour, viewpoint and border enhanced disparity energy model

    Get PDF
    The visual cortex is able to extract disparity information through the use of binocular cells. This process is reflected by the Disparity Energy Model, which describes the role and functioning of simple and complex binocular neuron populations, and how they are able to extract disparity. This model uses explicit cell parameters to mathematically determine preferred cell disparities, like spatial frequencies, orientations, binocular phases and receptive field positions. However, the brain cannot access such explicit cell parameters; it must rely on cell responses. In this article, we implemented a trained binocular neuronal population, which encodes disparity information implicitly. This allows the population to learn how to decode disparities, in a similar way to how our visual system could have developed this ability during evolution. At the same time, responses of monocular simple and complex cells can also encode line and edge information, which is useful for refining disparities at object borders. The brain should then be able, starting from a low-level disparity draft, to integrate all information, including colour and viewpoint perspective, in order to propagate better estimates to higher cortical areas.Portuguese Foundation for Science and Technology (FCT); LARSyS FCT [UID/EEA/50009/2013]; EU project NeuroDynamics [FP7-ICT-2009-6, PN: 270247]; FCT project SparseCoding [EXPL/EEI-SII/1982/2013]; FCT PhD grant [SFRH-BD-44941-2008
    corecore