检索结果-南通市图书馆

Influence of First-Order Phase Transition on the Single-Photon Spectra

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 1997年第9期14卷 648-651页

作者： AI Xiao-bai Institute of Nuclear Research Chinese Academy of SciencesShanghai 201800

A dynamical like-compact-star structure model is presented to treat the first-order phase transition from quark-gluon plasma to hadronic *** is found that the influence of latent heat released in phase transition on t... 详细信息

关键词： Transition transition quark

M-BCJR Algorithm with Channel Shortening Based on Ungerboeck Observation Model for Faster-than-Nyquist Signaling

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Communications 2021年第4期18卷 88-98页

作者： Hui Che Yong bai School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China School of Information and Communication Engineering Hainan UniversityHaikou 570228China

The M-BCJR algorithm based on the Ungerboeck observation model is a recent study to reduce the computational complexity for faster-than-Nyquist(FTN)signaling[1].In this paper,we propose a method that can further reduce the complexity with the approximately same or better bit error rate(BER)performance compared to[1].The information rate(IR)loss for the proposed method is less than 1%compared to the true achievable IR(AIR).The proposed improvement is mainly by introducing channel shortening(CS)before the M-BCJR *** our proposal,the Ungerboeck M-BCJR algorithm and CS can work together to defeat severe inter-symbol interference(ISI)introduced by FTN *** ISI length for the M-BCJR algorithm with CS is optimized based on the criterion of the IR *** the two cases=0.5 and=0.35,compared to Ungerboeck M-BCJR without CS benchmark[1],the computational complexities of Ungerboeck M-BCJR with CS are reduced by 75%.Moreover,for the case=0.35,the BER performance of Ungerboeck M-BCJR with CS outperforms that of the conventional M-BCJR in[1]at the low signal to noise ratio region.

关键词： M-BCJR Ungerboeck model channel shortening FTN reduced-complexity turbo equalization

Deep-learning-based nanowire detection in AFM images for automated nanomanipulation

在线全文

学校读者我要写书评

暂无评论

Nanotechnology and Precision Engineering 2021年第1期4卷 7-16页

作者： Huitian bai Sen Wu State Key Laboratory of Precision Measuring Technology and Instruments Tianjin UniversityTianjin 300072China

Atomic force microscope(AFM)-based nanomanipulation has been proved to be a possible method for assembling various nanoparticles into complex patterns and *** achieve efficient and fully automated nanomanipulation,nanoparticles on the substrate must be identified precisely and *** work focuses on an autodetection method for flexible nanowires using a deep learning *** instance segmentation network based on You Only Look Once version 3(YOLOv3)and a fully convolutional network(FCN)is applied to segment all movable nanowires in AFM *** with follow-up image morphology and fitting algorithms,this enables detection of postures and positions of nanowires at a high abstraction *** from these algorithms,our program is able to automatically detect nanowires of different morphologies with nanometer resolution and has over 90%reliability in the testing *** detection results are less affected by image complexity than the results of existing methods and demonstrate the good robustness of this algorithm.

关键词： Nanowire detection Instance segmentation YOLOv3 FCN Deep learning AFM

Recent Progress of Bio-inspired Camouflage Materials:From Visible to Infrared Range

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2023年第1期39卷 19-29页

作者： BU Xiaochen bai Hao State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou310027China

The adaptability of biological organisms to the environment is reflected in many aspects,especially in their camouflage of *** by biological camouflage strategies,a number of adaptive camouflage materials and devices have been developed to protect soldiers,vehicles,or equipment in the ***,the need for adaptive camouflage extends into people’s lives,whose privacy and information security need to be protected in the era of big ***,a review is provided on the recent advancements of adaptive camouflage from the perspective of biological organisms and bio-inspired ***,according to different biological mechanisms,we review the typical organisms that use pigmentary color,structural color,and morphological variation for adaptive camouflage,as well as those combine these ***,we provide an up-to-date review on recent developments in bio-inspired adaptive camouflage materials and devices with an emphasis on visible,infrared,and multispectral *** last,this review concludes the challenges and prospects for the future development of adaptive camouflage *** is noteworthy that there is never the best *** counter advanced detection techniques,it is necessary to unremittingly develop new materials and technologies to meet the increasing need for adaptive camouflage.

关键词： Bio-inspired material Adaptive camouflage Infrared camouflage Multispectral adaptability Structural color

Convergence analysis of Oja’s iteration for solving online PCA with nonzero-mean samples

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Mathematics 2021年第4期64卷 849-868页

作者： Siyun Zhou Yanqin bai Department of Mathematics Shanghai UniversityShanghai 200444China

Principal component analysis(PCA)is one of the most popular multivariate data analysis techniques for dimension reduction and data mining,and is widely used in many fields ranging from industry and biology to finance and social *** working on big data,it is of great necessity to consider the online version of PCA,in which only a small subset of samples could be *** handle the online PCA problem,Oja(1982)presented the stochastic power method under the assumption of zero-mean samples,and there have been lots of theoretical analysis and modified versions of this method in recent ***,a common circumstance where the samples have nonzero mean is seldom *** this paper,we derive the convergence rate of a nonzero-mean version of Oja’s algorithm with diminishing *** the analysis,we succeed in handling the dependency between each iteration,which is caused by the updated mean term for data ***,we verify the theoretical results by several numerical tests on both artificial and real *** work offers a way to deal with the top-1 online PCA when the mean of the given data is unknown.

关键词： online PCA Oja’s algorithm nonzero-mean samples convergence rate

Characterization and oil recovery enhancement by a polymeric nanogel combined with surfactant for sandstone reservoirs

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2021年第1期18卷 123-135页

作者： Mustafa Almahfood Baojun bai Missouri University of Science and Technology RollaMO 65401USA EXPEC Advanced Research Center Saudi AramcoDhahranSaudi Arabia

The characterization and enhanced oil recovery mechanisms of a nanosized polymeric cross-linked gel are presented herein.A negatively charged nanogel was synthesized using a typical free radical suspension polymerization process by employing 2-acrylamido 2-methyl propane sulfonic acid *** synthesized nanogel showed a narrow size distribution with one peak pointing to a predominant homogeneous droplet *** charged nanogels were also able to adsorb at the oil-water interfaces to reduce interfacial tension and stabilize oil-in-water emulsions,which ultimately improved the recovered oil from hydrocarbon *** addition,a fixed concentration of negatively charged surfactant(sodium dodecyl sulfate or SDS)was combined with different concentrations of the *** effect of the nanogels combined with surfactant on sandstone core plugs was examined by running a series of core flooding experiments using multiple flow *** results show that combining nanogel and SDS was able to reduce the interfacial tension to a value of 6 Nm/*** core flooding experiments suggest the ability of the nanogel,both alone and combined with SDS,to improve the oil recovery by a factor of 15%after initial seawater flooding.

关键词： Nanogel Polymeric nanogel Enhanced oil recovery

Magnetic and electrical transport study of the intrinsic magnetic topological insulator MnBi_(2)Te_(4)with Ge doping

在线全文

学校读者我要写书评

暂无评论

Frontiers of physics 2024年第3期19卷 51-59页

作者： Qingwang bai Mingxiang Xu School of Physics Southeast UniversityNanjing 211189China

As an intrinsic magnetic topological insulator with magnetic order and non-trivial topological structure,MnBi_(2)Te_(4)is an ideal material for studying exotic topological states such as quantum anomalous Hall effect and topological axion insulating ***,we carry out magnetic and electrical transport measurements on(Mn1–xGex)Bi_(2)Te_(4)(x=0,0.15,0.30,0.45,0.60,and 0.75)single *** is found that with increasing x,the dilution of magnetic moments gradually weakens the antiferromagnetic exchange ***,Ge doping reduces the critical field of ferromagnetic ordering,which may provide a possible way to implement the quantum anomalous Hall effect at lower magnetic *** transport measurements suggest that electrons are the dominant charge carriers,and the carrier density increases with the Ge doping ***,the Kondo effect is observed in the samples with x=0.45,0.60,and *** results suggest that doping germanium is a viable way to tune the magnetic and electrical transport properties of MnBi_(2)Te_(4),opening up the possibility of future applications in magnetic topological insulators.

关键词： MnBi_(2)Te_(4) intrinsic magnetic topological insulator transition points Kondo effect

Target searching based on modified implicit ROI encoding scheme

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2008年第5期19卷 888-892页

作者： bai Xu Zhang Zhongzhao Communication Research Center Harbin Inst. of Technology Harbin 150001 P. R. China

An EBCOT-based method is proposed to reduce the priority of background coefficients in the ROI code block without compromising algorithm complexity. The region of interest is encoded to a higher quality level than background, and the target searching time in video-guided penetrating missile can be shortened. Three kinds of coding schemes based on EBCOT are discussed. Experimental results demonstrate that the proposed method shows higher compression efficiency, lower complexity, and good reconstructed ROI image quality in the lower channel capacity.

关键词： video-guided penetrating bomb implicit ROI EBCOT.

Influence of laser geometric morphology type on Si C surface wettability

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2016年第4期59卷 592-596页

作者： WANG Rong bai ShaoXian College of Mechanical Engineering Zhejiang University of Technology

To obtain effective surface morphology to control surface wettability, this work investigated the influence of protuberant and concave morphology, which are respectively represented by circle-dimpled and micro-square-convex morphology, on surface wettability. The geometric morphologies were processed on silicon carbide （SIC） surfaces by a laser-marking machine, and surface wettability was monitored by the measurement of contact angles using the sessile drop method. Correlation analysis between contact angles and morphology parameters was conducted to determine the extent of influence. The results showed that the circle-dimpled diameter had a signific^mt influence on surface wettability, whereas grooved width did not. Additionally the depth of dimples and grooves exerted less influence on controlling wetting behaviors. In addition, surface wettability transformed from a superhydrophilic state to a hydrophobic state on micro-square-convex surfaces; contact angles on cir- cle-dimpled surfaces showed a relatively slow transformation, though the surface wettability also underwent the state change.

关键词： circle-dimpled morphology micro-square-convex morphology wettability SiC