This study first investigates the effect of the Madden-Julian Oscillation(MJO)on the Northern Hemisphere(NH)*** observations and simulations suggest significant cooling in the NH polar mesosphere approximately 35 days...
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This study first investigates the effect of the Madden-Julian Oscillation(MJO)on the Northern Hemisphere(NH)*** observations and simulations suggest significant cooling in the NH polar mesosphere approximately 35 days after MJO phase 4(P4),which lags the MJO-induced perturbation in the upper stratosphere by 10 *** enhanced planetary waves(PWs)propagate upward and result in wavenumber-1 pattern temperature anomalies in the mesosphere lagging MJO P4 by 25 *** anomalous PWs also lead to the weaker eastward zonal wind in the upper stratosphere and lower mesosphere lagging MJO P4 by 30 ***,the weaker westerlies result in weaker climatological westward gravity waves(GWs)in the mesosphere due to critical-level *** mesosphere meridional circulation is suppressed due to both anomalous PWs and GWs,and this suppression causes polar mesospheric cooling lagging MJO P4 by 35 days.
Satellite networks have been proposed as a vital component in 6G networks for providing global connections. In recent years, satellite network traffic has been increasing. However, the limited onboard resources and in...
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Most existing routing algorithms for Low-Earth-Orbit (LEO) satellite networks neglect the spatio-temporal features inherent in the network states, leading to suboptimal performance in scenarios with dynamic network to...
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The Caatinga biome is an important ecosystem in the semi-arid region of *** has significantly degraded due to human activities and is currently a region undergoing ***,monitoring the variation in the Caatinga biome ha...
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The Caatinga biome is an important ecosystem in the semi-arid region of *** has significantly degraded due to human activities and is currently a region undergoing ***,monitoring the variation in the Caatinga biome has become essential for its sustainable ***,traditional methods for estimating aboveground biomass(AGB)are time-consuming and *** sensing,such as optical and radar imaging,can estimate and correlate with ***,radar imaging is still a novelty to be applied in estimating the AGB of this biome,which is an area with little ***,this study aimed to use Sentinel-1 images to estimate the AGB of the Caatinga biome in Sergipe State(northeastern Brazil)and to verify its influencing *** sample plots(30 m×30 m)were selected,and the stems of individuals with a circumference at breast height(1.3 m above the ground)equal to or greater than 6.0 cm were measured,and the AGB through an allometric equation was *** Sentinel-1 images from 3 different periods(green,intermediate,and dry periods)were used to consider the phenological conditions of the Caatinga *** the pre-processing and extraction of attributes(co-polarized VV(vertical transmit and vertical receive),cross-polarized VH(vertical transmit and horizontal receive),and band ratio VH/VV backscatter,radar vegetation index,dual polarization synthetic aperture radar(SAR)vegetation index(DPSVI),entropy(H),and alpha angle(α))were performed with Sentinel’s Application *** attributes were used to estimate the AGB through simple and multiple linear regressions and evaluated by the coefficients of determination(R2),correlation(r),and root mean squared error(RMSE).The results showed that the attributes individually had little ability to estimate the AGB of the Caatinga biome in the three *** with multiple regression,we found that the intermediate period presented the equation with the best
Estimating an accurate six-degree-of-freedom(6-Do F)pose from correspondences with outliers remains a critical issue to 3D rigid *** sample consensus(RANSAC)and its variants are popular solutions to this *** there hav...
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Estimating an accurate six-degree-of-freedom(6-Do F)pose from correspondences with outliers remains a critical issue to 3D rigid *** sample consensus(RANSAC)and its variants are popular solutions to this *** there have been a number of RANSAC-fashion estimators,two issues remain ***,it is unclear which estimator is more appropriate to a particular ***,the impacts of different sampling strategies,hypothesis generation methods,hypothesis evaluation metrics,and stop criteria on the overall estimators remain *** work fills these gaps by first considering six existing RANSAC-fashion methods and then proposing eight variants for a comprehensive *** objective is to thoroughly compare estimators in the RANSAC family,and evaluate the effects of each key stage on the eventual 6-Do F pose estimation *** have been carried out on four standard datasets with different application scenarios,data modalities,and *** provide us with input correspondence sets with a variety of inlier ratios,spatial distributions,and *** on the experimental results,we summarize remarkable outcomes and valuable findings,so as to give practical instructions to real-world applications,and highlight current bottlenecks and potential solutions in this research realm.
Kitchen waste is a complex biomass waste, whose composition and properties vary with factors such as source, season and region. It is challenging to classify and characterize it. A thermogravimetric and kinetic study ...
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We do theoretical research on using high-speed rail(HSR)as an active source to perform reverse time migration(RTM)and analyze the influence of the interferometric field on the seismic imaging *** a train runs on a rai...
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We do theoretical research on using high-speed rail(HSR)as an active source to perform reverse time migration(RTM)and analyze the influence of the interferometric field on the seismic imaging *** a train runs on a rail viaduct,the evenly spaced piers of the viaduct generate a nearly spherical interferometric wavefield with radically travelling waves in frequency-determined *** find that the directions span stationary areas of the interference phases,of which cross-talks deteriorating HSR seismic imaging can be well suppressed by ***,we propose a method for performing RTM by employing HSR *** tests primarily verify the proposed method by use of 2 D and 3 D acoustic wave ***,we execute least square RTM to suppress crosstalk artifacts,further improving the imaging *** last,we stack images derived from trains with different velocities,which extends the frequency band,effectively overcoming the limit from the discrete spectrum of the source wavelet.
We propose a compression and rendering method for time-varying space environment volumes, by incorporating compression in temporal dimension into HVQ, based on the temporal coherence and cyclical change characteristic...
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In order to character the three dimensional (3D) charge distribution of particles and the six dimensional (6D) phase space in beam measurements, we study the transverse deflection structures (TDS) with variable polari...
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The spectral observations and analysis for the W80 region are presented by using the data of Medium-Resolution Spectroscopic Survey of Nebulae(MRS-N) with the Large Sky Area Multi-Object Fiber Spectroscopic Telescope(...
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The spectral observations and analysis for the W80 region are presented by using the data of Medium-Resolution Spectroscopic Survey of Nebulae(MRS-N) with the Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST).A total of 2982 high-quality nebular spectra have been obtained in the 20 square degree field of view which covers the W80 complex,and the largest sample of spectral data has been established for the first *** relative intensities,radial velocities(RVs),and full widths at half maximum(FWHMs) are measured with the high spectral resolution of LAMOST MRS-N,for Ha λ6563?,[NⅡ] λλ6548 A,6584 A,and [SⅡ] λλ6716A,6731 A emission *** the field of view of the whole W80 region,the strongest line emissions are found to be consistent with the bright nebulae NGC 7000,IC 5070,and LBN 391,and weak line emissions also exist in the Middle Region,where no bright nebulae are detected by the wide-band optical *** large-scale spectral observations of the W80 region reveal the systematic spatial variations of RVs and FWHMs,and several unique structural features.A "curved feature" to the east of NGC 7000,and a "jet feature" to the west of LBN 391 are detected to be showing larger RVs.A "wider FWHM region" is identified in the eastern part of NGC *** variations of[S Ⅱ]/Ha ratios display a gradient from southwest to northeast in the NGC 7000 region,and manifest a ring shape around the "W80 bubble" ionized by an O-type star in *** spectral and multi-band observations are guaranteed to investigate in detail the structural features.
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