A surface-based duct (SBD) is an abnormal atmospheric structure with a low probability of occurrence buta strong ability to trap electromagnetic waves. However, the existing research is based on the ...assumption that the range direction of the surface duct is homogeneous, which will lead to low productivity and large errors when applied in a real-marine environment. To alleviate these issues, we propose a framework for the inversion of inhomogeneous SBD M-profile based on a full-coupled convolutional Transformer (FCCT) deep learning network. We first designed a one-dimensional residual dilated causal convolution autoencoder to extract the feature representations from a high-dimension range direction inhomogeneous M-profile. Second, to improve efficiency and precision, we proposed a full-coupled convolutional Transformer (FCCT) that incorporated dilated causal convolutional layers to gain exponentially receptive field growth of the M-profile and help Transformer-like models improve the receptive field of each range direction inhomogeneous SBD M-profile information. We tested our proposed method performance on two sets of simulated sea clutter power data where the inversion of the simulated data reached 96.99% and 97.69%, which outperformed the existing baseline methods.
A new kind of hybrid RANS/LES turbulence modeling method - SST based SAS model is first time used for studying the stall phenomena in a centrifugal pump impeller at off-design condition in present ...paper. The previous reported “two channel” non-uniform flow structure has been gotten with this model. The numerical result is compared with LES and unsteady SST model, also the PIV result in reference paper. The time average result of flow show good agreements in general. The difference in turbulence quantities will affect the time average field in high turbulence intensity area to make SAS having close to LES. To achieve this effect, more computation consumption has been taken.
In the situation of high resolutions, high sea states and small grazing angles, the sea clutter amplitude distribution has heavy trailing part, this part has a significant impact on the sea surface ...target detection. This paper introduces a fusion method of sea clutter amplitude distribution model, based on which new amplitude distribution models of sea clutter can be designed, and thus the trailing part of the sea clutter amplitude distribution can be well fitted. Through the verification by using the sea clutter data of UHF, L, and S-band, it is indicated that the introduced fusion method can give a better fit in the trailing part of the sea clutter amplitude distribution than other conventional modeling methods. Further, for the amplitude distribution without heavy trailing part, this method also has a good fitness.
In millimeter wave (mmWave) massive MIMO (multiple-input multiple-output) systems, it is difficult to apply conventional digital precoding techniques due to hardware constraints. Fortunately, the ...hybrid precoding can be utilized to reduce power consumption and high costs. In this paper, a codebook-based hybrid precoding scheme for downlink multiuser mmWave massive MIMO systems is proposed. Our main idea is that the analog and digital precoders are designed separately to maximize the achievable sum rate. In the analog domain, we take the potential multiuser conflict and angular domain of channel matrix into consideration and propose an efficient conflicting-aware (CA) beam-column selection method to obtain a discrete Fourier transform (DFT) codebook-based analog precoder. According to the CA method, all users are classified into two groups, i.e., conflicting users (CUs) and non-conflicting users (NCUs). Different criteria of beam-column selection are applied for the two user groups. Then, zero-forcing (ZF) digital precoder is directly used in the digital domain. Simulation results illustrate that our proposed algorithm which has low complexity achieves satisfactory SR performance, which approaches that of the full digital precoding (the upper bound) and outperforms other existing hybrid algorithms.
Abstract
PIWI-interacting RNAs are a class of small RNAs that is most abundantly expressed in animal germline. Substantial research is going on to reveal the functions of piRNAs in the epigenetic and ...post-transcriptional regulation of transposons and genes. To collect and annotate these data, we developed piRBase, a database assisting piRNA functional study. Since its launch in 2014, piRBase has integrated 264 data sets from 21 organisms, and the number of collected piRNAs has reached 173 million. The latest piRBase release (v2.0, 2018) was more focused on the comprehensive annotation of piRNA sequences, as well as the increasing number of piRNAs. In addition, piRBase release v2.0 also contained the potential information of piRNA targets and disease related piRNA. All datasets in piRBase is free to access, and available for browse, search and bulk downloads at http://www.regulatoryrna.org/database/piRNA/.
The complete formation of stem-loop (i.e., hairpin) configuration on chip surface is of particular importance for the application of hairpin DNA (hpDNA) in building biosensors for various analytes ...with optimized performance. We report herein a convenient electrochemical protocol for evaluating the yield of hairpin DNA conformations upon self-assembly on electrode surface. As of the different hydrolysis capability of Exonuclease I (Exo I) toward single-stranded DNA (ssDNA) and hpDNA, we can selectively remove ssDNA from electrode but retain hpDNA strands; based on the changes in the cyclic voltammetric (CV) responses using Ru(NH3)63+ as redox indicators, we can then determine the fraction of hairpin configurations in mixed DNA self-assembled monolayers (SAMs). It was discovered that the molar fraction of hairpin configuration formed on the surface is considerably lower than that in the binary deposition solution (containing both ssDNA and hpDNA). The accuracy of the Exo I-assisted electrochemical quantitative protocol has been validated by standard DNA hybridization experiments; the relationship between the overall DNA packing density and the yield of hairpin configurations was also evaluated. More importantly, taking HIV-1 gene detection as a trial system, the hpDNA-based biosensor shows significantly improved detection limit and broadened response range upon the background reduction by Exo I-catalyzed hydrolysis.
Pan-genome analyses have shed light on the dynamics and evolution of bacterial genome from the point of population. The explosive growth of bacterial genome sequence also brought an extremely big ...challenge to pan-genome profile analysis. We developed a tool, named PanGP, to complete pan-genome profile analysis for large-scale strains efficiently. PanGP has integrated two sampling algorithms, totally random (TR) and distance guide (DG). The DG algorithm drew sample strain combinations on the basis of genome diversity of bacterial population. The performance of these two algorithms have been evaluated on four bacteria populations with strain numbers varying from 30 to 200, and the DG algorithm exhibited overwhelming advantage on accuracy and stability than the TR algorithm.
Availability: PanGP was developed with a user-friendly graphic interface and it was available at http://PanGP.big.ac.cn.
Contact:
xiaojingfa@big.ac.cn or wujy@big.ac.cn
Supplementary information:
Supplementary data are available at Bioinformatics online.
•The solution with Span-80 has greater atomization performance than that with other surfactants (SDS, CTAB and TX-100)•The interaction between ethanol and SDS is largest because the sodium ions in ...SDS react with alkoxy negative ions.•The ethanol atomization morphology transforms from continuous jet to spindle under the synergistic effect of surfactant and salt ions.•An increase in Span-80 concentration promotes the formation of hydrogen bond between ethanol molecules.
Electrospray in the cone-jet regime could produce highly charged and fine monodisperse drops, and further disintegrates into nanoscale drops, even ions due to synergism of Rayleigh instability and evaporation. The jet and its breakup instability into drops are significantly affected by liquid properties including surface tension, conductivity, density and others. Surfactants may play important roles on gas-liquid interface and are usually added in solution to vary liquid property and may further affect electrospray behaviors. In present work, the ethanol containing surfactants is atomized in the cone-jet to discuss the synergistic effect of surfactant types, concentrations and surfactant-salt on the jet evolution behaviors under direct current electric fields using molecular dynamics (MD) method. It is found that the jet length of ethanol solution with Span-80 is the longest (Span-80, SDS, CTAB and TX-100), while it has excellent dispersion. The addition of CTAB could make ethanol solution transform from continuous jet into dripping. SDS interacts most violently with ethanol due to the presence of sodium ions. As surfactant concentration increasing, the number of solution molecules sprayed remarkably increases, while the interaction generated from ethanol decreases. The number of molecular clusters (composed of three or more ethanol molecules) in the cone-jet electrospray increases with increasing Span-80 concentration. It is also found that the addition of Span-80 slightly changes the average bond angle of ethanol and bond angle distribution. The ethanol atomization morphology transforms to spindle becasue of the synergistic effect of surfactant and salt ions. The interaction generated between ethanol molecules plays a dominating role and decreases due to the generation of spindle-shaped drops. The hydrogen bond generated from ethanol decreases with increasing conductivity and surface tension. The conclusions of this paper will be latent value for the optimization of physical parameters in electrospray.
N, S and O doped Co/CoO/Co9S8@carbon derived from metal-organic framework with superhydrophilicity was prepared for efficiently activate PMS to degrade SMX.
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•Lamellar ...Co/CoO/Co9S8@NSOC has been synthesized by calcinating a Co-MOF containing N,S,O-donor ligands.•SMX removal efficiency was 91.85% after 2 min with a high rate constant of 1.31 min−1.•Multiple cobalt species, hetero-atom doping, superhydrophilic surface contribute to the high ability of PMS activation.•The catalyst was loaded on the membrane and sponge to utilize in the flowing and static system, respectively.
Herein, a N,S,O-doped Co/CoO/Co9S8@carbon hybrid (Co/CoO/Co9S8@NSOC) has been constructed by calcinating a Co-based metal–organic framework (Co-MOF) with 4,4-bipyridine and 2,5-thiophenedicarboxylic acid as linkers. Co/CoO/Co9S8@NSOC exhibited a high and recycled catalytic efficiency for peroxymonosulfate (PMS) activation to degrade sulfamethoxazole (SMX, 20 mg/L) with a reaction rate of 1.31 min−1, which was 5.2 times than that of Co-MOF. The catalytic behavior should be attributed to the rich active sites, lamellar morphology, superhydrophilicity, and magnetism. Furthermore, the Co/CoO/Co9S8@NSOC was immobilized on a filter membrane (CMFM) to adapt to the flowing system, which could recycle 20 times without losing activity. To employ in a large-scale static environment, the Co/CoO/Co9S8@NSOC was loaded on the commercial sponge (CoSPG). In a 50 L water tank, the CoSPG realized to decompose 160 mg/L SMX solution with 37 h and had long-term stability over 10 days. Notably, the PMS cost of treating one ton of wastewater is only $0.34, indicating a huge industrial application value.
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