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On Generalities of Chinese Names and English Names
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作者 唐志娟 《海外英语》 2010年第10X期273-275,共3页
Name system has developed simultaneously with the change of world language.Generalities of Chinese names and English names are discussed from 8 aspects.Meanwhile,the structural changes of names in Chinese and English ... Name system has developed simultaneously with the change of world language.Generalities of Chinese names and English names are discussed from 8 aspects.Meanwhile,the structural changes of names in Chinese and English are also contrasted in order to make some further exploration.Readers may more deeply understand the specific regularity of the individual languages after knowing several generalities. 展开更多
关键词 generalities CHINESE NAMES ENGLISH NAMES
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General anesthetic agents induce neurotoxicity through oligodendrocytes in the developing brain 被引量:1
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作者 Wen-Xin Hang Yan-Chang Yang +7 位作者 Yu-Han Hu Fu-Quan Fang Lang Wang Xing-Hua Qian Patrick M.McQuillan Hui Xiong Jian-Hang Leng Zhi-Yong Hu 《Zoological Research》 SCIE CSCD 2024年第3期691-703,共13页
General anesthetic agents can impact brain function through interactions with neurons and their effects on glial cells.Oligodendrocytes perform essential roles in the central nervous system,including myelin sheath for... General anesthetic agents can impact brain function through interactions with neurons and their effects on glial cells.Oligodendrocytes perform essential roles in the central nervous system,including myelin sheath formation,axonal metabolism,and neuroplasticity regulation.They are particularly vulnerable to the effects of general anesthetic agents resulting in impaired proliferation,differentiation,and apoptosis.Neurologists are increasingly interested in the effects of general anesthetic agents on oligodendrocytes.These agents not only act on the surface receptors of oligodendrocytes to elicit neuroinflammation through modulation of signaling pathways,but also disrupt metabolic processes and alter the expression of genes involved in oligodendrocyte development and function.In this review,we summarize the effects of general anesthetic agents on oligodendrocytes.We anticipate that future research will continue to explore these effects and develop strategies to decrease the incidence of adverse reactions associated with the use of general anesthetic agents. 展开更多
关键词 OLIGODENDROCYTES General anesthetic agents NEUROTOXICITY Central nervous system Perioperative neurocognitive disorders
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In vivo imaging reveals a synchronized correlation among neurotransmitter dynamics during propofol and sevoflurane anesthesia 被引量:1
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作者 Gao-Lin Qiu Li-Jun Peng +6 位作者 Peng Wang Zhi-Lai Yang Ji-Qian Zhang Hu Liu Xiao-Na Zhu Jin Rao Xue-Sheng Liu 《Zoological Research》 SCIE CSCD 2024年第3期679-690,共12页
General anesthesia is widely applied in clinical practice.However,the precise mechanism of loss of consciousness induced by general anesthetics remains unknown.Here,we measured the dynamics of five neurotransmitters,i... General anesthesia is widely applied in clinical practice.However,the precise mechanism of loss of consciousness induced by general anesthetics remains unknown.Here,we measured the dynamics of five neurotransmitters,includingγ-aminobutyric acid,glutamate,norepinephrine,acetylcholine,and dopamine,in the medial prefrontal cortex and primary visual cortex of C57BL/6 mice through in vivo fiber photometry and genetically encoded neurotransmitter sensors under anesthesia to reveal the mechanism of general anesthesia from a neurotransmitter perspective.Results revealed that the concentrations of γ-aminobutyric acid,glutamate,norepinephrine,and acetylcholine increased in the cortex during propofol-induced loss of consciousness.Dopamine levels did not change following the hypnotic dose of propofol but increased significantly following surgical doses of propofol anesthesia.Notably,the concentrations of the five neurotransmitters generally decreased during sevoflurane-induced loss of consciousness.Furthermore,the neurotransmitter dynamic networks were not synchronized in the non-anesthesia groups but were highly synchronized in the anesthetic groups.These findings suggest that neurotransmitter dynamic network synchronization may cause anesthetic-induced loss of consciousness. 展开更多
关键词 General anesthesia Loss of consciousness In vivo neurotransmitter imaging Medial prefrontal cortex Primary visual cortex
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Application of Regularization Methods in the Sky Map Reconstruction of the Tianlai Cylinder Pathfinder Array
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作者 Kaifeng Yu Shifan Zuo +2 位作者 Fengquan Wu Yougang Wang Xuelei Chen 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第2期24-35,共12页
The Tianlai cylinder pathfinder is a radio interferometer array to test 21 cm intensity mapping techniques in the post-reionization era.It works in passive drift scan mode to survey the sky visible in the northern hem... The Tianlai cylinder pathfinder is a radio interferometer array to test 21 cm intensity mapping techniques in the post-reionization era.It works in passive drift scan mode to survey the sky visible in the northern hemisphere.To deal with the large instantaneous field of view and the spherical sky,we decompose the drift scan data into m-modes,which are linearly related to the sky intensity.The sky map is reconstructed by solving the linear interferometer equations.Due to incomplete uv coverage of the interferometer baselines,this inverse problem is usually ill-posed,and regularization method is needed for its solution.In this paper,we use simulation to investigate two frequently used regularization methods,the Truncated Singular Value Decomposition(TSVD),and the Tikhonov regularization techniques.Choosing the regularization parameter is very important for its application.We employ the generalized cross validation method and the L-curve method to determine the optimal value.We compare the resulting maps obtained with the different regularization methods,and for the different parameters derived using the different criteria.While both methods can yield good maps for a range of regularization parameters,in the Tikhonov method the suppression of noisy modes are more gradually applied,produce more smooth maps which avoids some visual artefacts in the maps generated with the TSVD method. 展开更多
关键词 techniques interferometric-methods numerical-cosmology observations-radio continuum general
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A Galaxy Image Augmentation Method Based on Few-shot Learning and Generative Adversarial Networks
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作者 Yiqi Yao Jinqu Zhang +1 位作者 Ping Du Shuyu Dong 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第3期180-193,共14页
Galaxy morphology classifications based on machine learning are a typical technique to handle enormous amounts of astronomical observation data,but the key challenge is how to provide enough training data for the mach... Galaxy morphology classifications based on machine learning are a typical technique to handle enormous amounts of astronomical observation data,but the key challenge is how to provide enough training data for the machine learning models.Therefore this article proposes an image data augmentation method that combines few-shot learning and generative adversarial networks.The Galaxy10 DECaLs data set is selected for the experiments with consistency,variance,and augmentation effects being evaluated.Three popular networks,including AlexNet,VGG,and ResNet,are used as examples to study the effectiveness of different augmentation methods on galaxy morphology classifications.Experiment results show that the proposed method can generate galaxy images and can be used for expanding the classification model’s training set.According to comparative studies,the best enhancement effect on model performance is obtained by generating a data set that is 0.5–1 time larger than the original data set.Meanwhile,different augmentation strategies have considerably varied effects on different types of galaxies.FSL-GAN achieved the best classification performance on the ResNet network for In-between Round Smooth Galaxies and Unbarred Loose Spiral Galaxies,with F1 Scores of 89.54%and 63.18%,respectively.Experimental comparison reveals that various data augmentation techniques have varied effects on different categories of galaxy morphology and machine learning models.Finally,the best augmentation strategies for each galaxy category are suggested. 展开更多
关键词 techniques image processing-galaxies structure-galaxies general
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Analysis of Bright Source Hardness Ratios in the 4 yr Insight-HXMT Galactic Plane Scanning Survey Catalog
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作者 Chen Wang Jin-Yuan Liao +5 位作者 Ju Guan Yuan Liu Cheng-Kui Li Na Sai Jing Jin Shuang-Nan Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第2期154-170,共17页
We conduct a statistical analysis of the hardness ratio(HR)for bright sources in the 4 yr Galactic Plane Scanning Survey catalog of Insight-HXMT.Depending on the stable(variable)flux F_(s)(F_(v))or spectrum S_(s)(S_(v... We conduct a statistical analysis of the hardness ratio(HR)for bright sources in the 4 yr Galactic Plane Scanning Survey catalog of Insight-HXMT.Depending on the stable(variable)flux F_(s)(F_(v))or spectrum S_(s)(S_(v))of each source,the bright sources are classified into three groups:F_(v)&S_(v),F_(v)&S_(s),and F_(s)&_(s).Our study of the HR characteristics in different types of sources reveals that accretion-powered neutron star(NS)low-mass X-ray binaries(LMXBs)exhibit softer energy spectra than NS high-mass X-ray binaries(HMXBs),but harder energy spectra than black hole binaries in most cases.This difference is probably due to their different magnetic field strengths.Additionally,Fv&Sv LMXBs tend to be harder than Fv&Ss LMXBs below 7 keV,while the opposite is true for HMXBs.Our results suggest that LMXBs may dominate unclassified sources,and NS binaries are likely to be the primary type of X-ray binaries with ambiguous compact stars.By comparing the HR of transient sources in their outburst and low-flux states,it is found that the averaged HR of four sources in the two states are roughly comparable within uncertainties.We also investigate the spatial properties of the three groups and find that Fv&Sv sources are mainly located in the longitude of-20°<l<9°,Fv&Ss sources cross the Galactic Plane,and Fs&Ss sources are predominantly concentrated in 19°<l<42°.In addition,analyzing the HR spatial distributions shows the absorption of soft X-rays(primarily below 2 keV)in the Galactic Plane. 展开更多
关键词 catalogs-surveys-methods data analysis-X-rays general
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Study of 26 Galactic Open Clusters with Extended Main-sequence Turnoffs
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作者 Yang-Yang Deng Zhong-Mu Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期28-37,共10页
Recent studies indicate that some Galactic open clusters(OCs)exhibit extended main-sequence turnoff(eMSTO)in their color–magnitude diagrams(CMDs).However,the number of Galactic OCs with eMSTO structures detected so f... Recent studies indicate that some Galactic open clusters(OCs)exhibit extended main-sequence turnoff(eMSTO)in their color–magnitude diagrams(CMDs).However,the number of Galactic OCs with eMSTO structures detected so far is limited,and the reasons for their formation are still unclear.This work identifies 26 Galactic OCs with undiscovered eMSTOs and investigates the causes of these features.Stellar population types and fundamental parameters of cluster samples are acquired using CMD fitting methods.Among them,the results of 11 OCs are reliable as the observed CMDs are well-reproduced.We propose the crucial role of stellar binarity and confirm the importance of stellar rotation in reproducing eMSTO morphologies.The results also show that the impact of age spread is important,as it can adequately explain the structure of young OCs and fit the observed CMDs of intermediate-age OCs better. 展开更多
关键词 (stars:)binaries:general Galaxy:fundamental parameters (Galaxy:)open clusters and associations:general (stars:)Hertzsprung Russell and C-M-diagrams
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Symptom presentation and evolution in the first 48 hours after injury are associated with return to play after concussion in elite Rugby Union
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作者 Ross Tucker Matt Cross +7 位作者 Keith Stokes Lindsay Starling Rosy Hyman Simon Kemp Stephen West Martin Raftery Eanna Falvey James Brown 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第3期387-397,共11页
Background:Return to play(RTP)in elite rugby is managed using a 6-stage graduated RTP protocol,which can result in clearance to play within 1 week of injury.We aimed to explore how symptom,cognitive,and balance presen... Background:Return to play(RTP)in elite rugby is managed using a 6-stage graduated RTP protocol,which can result in clearance to play within 1 week of injury.We aimed to explore how symptom,cognitive,and balance presentation and evolution during concussion screens 2 h(head injury assessment(HIA2)and 48 h(HIA3)after injury were associated with time to RTP)to identify whether a more conservative graduated RTP may be appropriate.Methods:A retrospective cohort study was conducted in 380 concussed rugby players from elite men’s rugby over 3 consecutive seasons.Players were classified as shorter or longer returns,depending on whether RTP occurred within 7 days(allowing them to be considered to play the match 1 week after injury)or longer than 8 days,respectively.Symptom,cognitive,and balance performance during screens was assessed relative to baseline(normal or abnormal)and to the preceding screen(improving or worsening).Associations between sub-test abnormalities and RTP time were explored using odds ratios(OR,longer vs.shorter).Median day absence was compared between players with abnormal or worsening results and those whose results were normal or improving.Results:Abnormal symptom results during screens 2 h and 48 h after concussion were associated with longer return time(HIA2:OR=2.21,95%confidence interval(95%CI):1.39-3.50;HIA3:OR=3.30,95%CI:1.89-5.75).Worsening symptom number or severity from the time of injury to 2 h and 48 h post-injury was associated with longer return(HIA2:OR=2.49,95%CI:1.36-4.58;HIA3:OR=3.34,95%CI:1.10-10.15).Median days absence was greater in players with abnormal symptom results at both HIA2 and HIA3.Cognitive and balance performance were not associated with longer return and did not affect median days absence.Conclusion:Symptom presentation and evolution within 48 h of concussion were associated with longer RTP times.This may guide a more conservative approach to RTP,while still adhering to individualized concussion management principles. 展开更多
关键词 Brain injury Concussion management General return to play Medical management
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A Rendezvous Mission to the Second Earth Trojan Asteroid 2020 XL_5 with Low-Thrust Multi-Gravity Assist Techniques
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作者 Shi-Hai Yang Bo Xu Xin Li 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期245-264,共20页
As the second of Earth's Trojan asteroids, 2020 XL_(5) is worthy of rendezvous and even sample return missions in many aspects. In this paper, a rendezvous mission to Earth's second Trojan asteroid 2020 XL_(5)... As the second of Earth's Trojan asteroids, 2020 XL_(5) is worthy of rendezvous and even sample return missions in many aspects. In this paper, a rendezvous mission to Earth's second Trojan asteroid 2020 XL_(5) is proposed.However, due to its high inclination and large eccentricity, direct impulsive transfer requires large amounts of fuel consumption. To address this challenge, we explore the benefits of electric propulsion and multi-gravity assist techniques for interplanetary missions. These two techniques are integrated in this mission design. The design of a low-thrust gravity-assist(LTGA) trajectory in multi-body dynamics is thoroughly investigated,which is a complex process. A comprehensive framework including three steps is presented here for optimization of LTGA trajectories in multi-body dynamics. The rendezvous mission to 2020 XL_(5) is designed with this three-step approach. The most effective transfer sequence among the outcomes involves Earth–Venus–Earth–Venus-2020 XL_(5). Numerical results indicate that the combination of electric propulsion and multi-gravity assists can greatly reduce the fuel consumption, with fuel consumption of 9.03%, making it a highly favorable choice for this rendezvous mission. 展开更多
关键词 minor planets asteroids:general celestial mechanics Planetary Systems
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Accelerating Asteroidal Period and Pole Inversion from Multiple Lightcurves Using Parallel Differential Evolution and Cellinoid Shape Model
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作者 Yong-Xiong Zhang Wen-Xiu Guo +4 位作者 Xiao-Ping Lu Hua Zheng Hai-Bin Zhao Jun Tian Wei-Lin Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第4期271-286,共16页
Determining asteroid properties provides valuable physical insights but inverting them from photometric lightcurves remains computationally intensive.This paper presents a new approach that combines a simplified Celli... Determining asteroid properties provides valuable physical insights but inverting them from photometric lightcurves remains computationally intensive.This paper presents a new approach that combines a simplified Cellinoid shape model with the Parallel Differential Evolution(PDE)algorithm to accelerate inversion.The PDE algorithm is more efficient than the Differential Evolution algorithm,achieving an extraordinary speedup of 37.983 with 64 workers on multicore CPUs.The PDE algorithm accurately derives period and pole values from simulated data.The analysis of real asteroid lightcurves validates the method’s reliability:in comparison with results published elsewhere,the PDE algorithm accurately recovers the rotational periods and,given adequate viewing geometries,closely matches the pole orientations.The PDE approach converges to solutions within 20,000 iterations and under one hour,demonstrating its potential for large-scale data analysis.This work provides a promising new tool for unveiling asteroid physical properties by overcoming key computational bottlenecks. 展开更多
关键词 methods:numerical minor planets asteroids:general techniques:photometric astrom
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Rotating Massive Strangeon Stars and X-Ray Plateau of Short GRBs
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作者 Xi-Yan Yang Xiao-Yu Lai +1 位作者 Wei-Wei Tan Ren-Xin Xu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第3期47-57,共11页
Strangeon stars,which are proposed to describe the nature of pulsar-like compact stars,have passed various observational tests.The maximum mass of a non-rotating strangeon star could be high,which implies that the rem... Strangeon stars,which are proposed to describe the nature of pulsar-like compact stars,have passed various observational tests.The maximum mass of a non-rotating strangeon star could be high,which implies that the remnants of binary strangeon star mergers could even be long-lived massive strangeon stars.We study rigidly rotating strangeon stars in the slowly rotating approximation,using the Lennard-Jones model for the equation of state.Rotation can significantly increase the maximum mass of strangeon stars with unchanged baryon numbers,enlarging the mass-range of long-lived strangeon stars.During spin-down after merger,the decrease of radius of the remnant will lead to the release of gravitational energy.Taking into account the efficiency of converting the gravitational energy luminosity to the observed X-ray luminosity,we find that the gravitational energy could provide an alternative energy source for the plateau emission of X-ray afterglow.The fitting results of X-ray plateau emission of some short gamma-ray bursts suggest that the magnetic dipole field strength of the remnants can be much smaller than that of expected when the plateau emission is powered only by spin-down luminosity of magnetars. 展开更多
关键词 dense matter-(stars) PULSARS general-(stars) gamma-ray burst GENERAL
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Advancing computer-generated holographic display thanks to diffraction model-driven deep nets
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作者 Vittorio Bianco Pietro Ferraro 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第1期1-3,共3页
Advancements are reported in computer-generated holography proofing RGB 4K display through a new strategy based on diffraction model-driven deep networks. In the new 4K-DMDNet, the network is not a “black box” anymo... Advancements are reported in computer-generated holography proofing RGB 4K display through a new strategy based on diffraction model-driven deep networks. In the new 4K-DMDNet, the network is not a “black box” anymore. Rather, the input-output relation must obey to the physics of wavefront propagation, which is embedded here as a constraint. Thus, a labelled dataset is not required, and the model shows superior generalization capabilities with respect to data-driven approaches. The method is promising for the new generation of RGB 4K holographic display, as well as augmented and virtual reality systems. 展开更多
关键词 HOLOGRAPHIC GENERALIZATION CONSTRAINT
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Higher-order expansions of powered extremes of logarithmic general error distribution
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作者 TAN Xiao-feng LI Li-hui 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期47-54,共8页
In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥1.Higher-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of nor... In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥1.Higher-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of normalizing constants.It is shown that M_(n)^(p),when v=1,converges to the Frechet extreme value distribution at the rate of 1/n,and if v>1 then M_(n)^(p)converges to the Gumbel extreme value distribution at the rate of(loglogn)^(2)=(log n)^(1-1/v). 展开更多
关键词 logarithmic general error distribution convergence rate higher-order expansion powered ex-treme
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Research on Site Planning of Mobile Communication Network
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作者 Jiahan He Guangjun Liang +3 位作者 Meng Li KefanYao Bixia Wang Lu Li 《Computers, Materials & Continua》 SCIE EI 2024年第8期3243-3261,共19页
In this paper,considering the cost of base station,coverage,call quality,and other practical factors,a multi-objective optimal site planning scheme is proposed.Firstly,based on practical needs,mathematical modeling me... In this paper,considering the cost of base station,coverage,call quality,and other practical factors,a multi-objective optimal site planning scheme is proposed.Firstly,based on practical needs,mathematical modeling methods were used to establish mathematical expressions for the three sub-objectives of cost objectives,coverage objectives,and quality objectives.Then,a multi-objective optimization model was established by combining threshold and traffic volume constraints.In order to reduce the time complexity of optimization,a non-dominated sorting genetic algorithm(NSGA)is used to solve the multi-objective optimization problem of site planning.Finally,a strategy for clustering and optimizing weak coverage areas was proposed.In order to avoid redundant neighborhood retrieval during cluster expansion,the Fast Density-Based Spatial Clustering of Applications with Noise(FDBSCAN)clustering method was adopted.With different sub-objectives as the main objectives,this paper obtained the distribution map of weak coverage areas before and after the establishment of new base stations,as well as relevant site planning maps,and provided three planning schemes for different main objectives.The simulation results show that the traffic coverage of the three station planning schemes is above 90%.The change in the main optimization objective will result in a significant difference between the cost of the three solutions and the coverage of weak coverage points. 展开更多
关键词 Siting of station multi-objective optimization genetic algorithm NSGA general greed FDBSCAN cluster
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INCOMPRESSIBLE LIMIT OF IDEAL MAGNETOHYDRODYNAMICS IN A DOMAIN WITH BOUNDARIES
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作者 Qiangchang JU Jiawei WANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1441-1465,共25页
We study the incompressible limit of classical solutions to compressible ideal magneto-hydrodynamics in a domain with a flat boundary.The boundary condition is characteristic and the initial data is general.We first e... We study the incompressible limit of classical solutions to compressible ideal magneto-hydrodynamics in a domain with a flat boundary.The boundary condition is characteristic and the initial data is general.We first establish the uniform existence of classical solutions with respect to the Mach number.Then,we prove that the solutions converge to the solution of the incompressible MHD system.In particular,we obtain a stronger convergence result by using the dispersion of acoustic waves in the half space. 展开更多
关键词 incompressible limit ideal MHD equations boundary condition general initial data
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Image Steganography by Pixel-Value Differencing Using General Quantization Ranges
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作者 Da-Chun Wu Zong-Nan Shih 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期353-383,共31页
A new steganographic method by pixel-value differencing(PVD)using general quantization ranges of pixel pairs’difference values is proposed.The objective of this method is to provide a data embedding technique with a ... A new steganographic method by pixel-value differencing(PVD)using general quantization ranges of pixel pairs’difference values is proposed.The objective of this method is to provide a data embedding technique with a range table with range widths not limited to powers of 2,extending PVD-based methods to enhance their flexibility and data-embedding rates without changing their capabilities to resist security attacks.Specifically,the conventional PVD technique partitions a grayscale image into 1×2 non-overlapping blocks.The entire range[0,255]of all possible absolute values of the pixel pairs’grayscale differences in the blocks is divided into multiple quantization ranges.The width of each quantization range is a power of two to facilitate the direct embedding of the bit information with high embedding rates.Without using power-of-two range widths,the embedding rates can drop using conventional embedding techniques.In contrast,the proposed method uses general quantization range widths,and a multiple-based number conversion mechanism is employed skillfully to implement the use of nonpower-of-two range widths,with each pixel pair being employed to embed a digit in the multiple-based number.All the message bits are converted into a big multiple-based number whose digits can be embedded into the pixel pairs with a higher embedding rate.Good experimental results showed the feasibility of the proposed method and its resistance to security attacks.In addition,implementation examples are provided,where the proposed method adopts non-power-of-two range widths and employsmultiple-based number conversion to expand the data-hiding and steganalysis-resisting capabilities of other PVD methods. 展开更多
关键词 STEGANOGRAPHY pixel-value differencing multiple-based number conversion general quantization range
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Point-symmetry in SNR G1.9+0.3:A Supernova that Destroyed its Planetary Nebula Progenitor
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作者 Noam Soker 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第1期165-172,共8页
I analyze a new X-ray image of the youngest supernova remnant(SNR)in the Galaxy,which is the type Ia SNR G1.9+0.3,and reveal a very clear point-symmetrical structure.Since explosion models of type Ia supernovae(SNe Ia... I analyze a new X-ray image of the youngest supernova remnant(SNR)in the Galaxy,which is the type Ia SNR G1.9+0.3,and reveal a very clear point-symmetrical structure.Since explosion models of type Ia supernovae(SNe Ia)do not form such morphologies,the point-symmetrical morphology must come from the circumstellar material(CSM)into which the ejecta expands.The large-scale point-symmetry that I identify and the known substantial deceleration of the ejecta of SNR G1.9+0.3 suggest a relatively massive CSM of■1M⊙.I argue that the most likely explanation is the explosion of this SN Ia into a planetary nebula.The scenario that predicts a large fraction of SN Ia inside PNe(SNIPs)is the core degenerate scenario.Other SN Ia scenarios might lead to only a very small fraction of SNIPs or none at all. 展开更多
关键词 (stars:)supernovae:general ISM:supernova remnants (stars:)binaries(including multiple):close (ISM:)planetary nebulae:general stars:jets
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Extended wet sieving method for determination of complete particle size distribution of general soils
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作者 Shengnan Ma Yi Song +2 位作者 Jiawei Liu Xingyu Kang Zhongqi Quentin Yue 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期242-257,共16页
The traditional standard wet sieving method uses steel sieves with aperture?0.063 mm and can only determine the particle size distribution(PSD)of gravel and sand in general soil.This paper extends the traditional meth... The traditional standard wet sieving method uses steel sieves with aperture?0.063 mm and can only determine the particle size distribution(PSD)of gravel and sand in general soil.This paper extends the traditional method and presents an extended wet sieving method.The extended method uses both the steel sieves and the nylon filter cloth sieves.The apertures of the cloth sieves are smaller than 0.063 mm and equal 0.048 mm,0.038 mm,0.014 mm,0.012 mm,0.0063 mm,0.004 mm,0.003 mm,0.002 mm,and 0.001 mm,respectively.The extended method uses five steps to separate the general soil into many material sub-groups of gravel,sand,silt and clay with known particle size ranges.The complete PSD of the general soil is then calculated from the dry masses of the individual material sub-groups.The extended method is demonstrated with a general soil of completely decomposed granite(CDG)in Hong Kong,China.The silt and clay materials with different particle size ranges are further examined,checked and verified using stereomicroscopic observation,physical and chemical property tests.The results further confirm the correctness of the extended wet sieving method. 展开更多
关键词 Particle size distribution(PSD) General soil SILT CLAY Wet sieving Physical and chemical properties
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通智测试——基于动态具身物理社会交互环境的通用人工智能测试
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作者 Yujia Peng Jiaheng Han +7 位作者 Zhenliang Zhang Lifeng Fan Tengyu Liu Siyuan Qi Xue Feng Yuxi Ma Yizhou Wang Song-Chun Zhu 《Engineering》 SCIE EI CAS CSCD 2024年第3期12-22,共11页
The release of the generative pre-trained transformer(GPT)series has brought artificial general intelligence(AGI)to the forefront of the artificial intelligence(AI)field once again.However,the questions of how to defi... The release of the generative pre-trained transformer(GPT)series has brought artificial general intelligence(AGI)to the forefront of the artificial intelligence(AI)field once again.However,the questions of how to define and evaluate AGI remain unclear.This perspective article proposes that the evaluation of AGI should be rooted in dynamic embodied physical and social interactions(DEPSI).More specifically,we propose five critical characteristics to be considered as AGI benchmarks and suggest the Tong test as an AGI evaluation system.The Tong test describes a value-and ability-oriented testing system that delineates five levels of AGI milestones through a virtual environment with DEPSI,allowing for infinite task generation.We contrast the Tong test with classical AI testing systems in terms of various aspects and propose a systematic evaluation system to promote standardized,quantitative,and objective benchmarks and evaluation of AGI. 展开更多
关键词 Artificial general intelligence Artificial intelligence benchmark Artificial intelligence evaluation Embodied artificial intelligence Value alignment Turing test CAUSALITY
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Cluster Analysis of the Roma-BZCAT Blazars
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作者 Dmitry O.Kudryavtsev Yulia V.Sotnikova +5 位作者 Vladislav A.Stolyarov Timur V.Mufakharov Valery V.Vlasyuk Margarita L.Khabibullina Alexander G.Mikhailov Yulia V.Cherepkova 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第5期117-139,共23页
Based on the collected multiwavelength data, namely in the radio(NVSS, FIRST, RATAN-600), IR(WISE),optical(Pan-STARRS), UV(GALEX), and X-ray(ROSAT, Swift-XRT) ranges, we have performed a cluster analysis for the blaza... Based on the collected multiwavelength data, namely in the radio(NVSS, FIRST, RATAN-600), IR(WISE),optical(Pan-STARRS), UV(GALEX), and X-ray(ROSAT, Swift-XRT) ranges, we have performed a cluster analysis for the blazars of the Roma-BZCAT catalog. Using two machine learning methods, namely a combination of PCA with k-means clustering and Kohonen's self-organizing maps(SOMs), we have constructed an independent classification of the blazars(five classes) and compared the classes with the known Roma-BZCAT classification(FSRQs, BL Lacs, galaxy-dominated BL Lacs, and blazars of an uncertain type) as well as with the high synchrotron peaked(HSP) blazars from the 3HSP catalog and blazars from the TeVCat catalog. The obtained groups demonstrate concordance with the BL Lac/FSRQ classification along with a continuous character of the change in the properties. The group of HSP blazars stands out against the overall distribution. We examine the characteristics of the five groups and demonstrate distinctions in their spectral energy distribution shapes. The effectiveness of the clustering technique for objective analysis of multiparametric arrays of experimental data is demonstrated. 展开更多
关键词 methods data analysis-galaxies active-(galaxies:)BL Lacertae objects GENERAL
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