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A new trend in nuclear physics development

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Science China(Physics,Mechanics & Astronomy) 2017年第10期60卷 83-84页

作者： bing guo NaiYan Wang Department of Nuclear Physics China Institute of Atomic Energy Beijing 102413 China

Atomic nuclei comprise a principal level of material *** physics,in itself an substantial area of study,serves as a link between atomic physics and particle *** main research areas of nuclear physics involve strong in... 详细信息

关键词：物理学发展电磁相互作用粒子物理学原子物理学强相互作用弱相互作用材料结构核物理

Connection Between Continuous Optimization and Turán Densities of Non-uniform Hypergraphs

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Acta Mathematicae Applicatae Sinica 2021年第4期37卷 858-866页

作者： Xiao-bing guo Yue-jian PENG School of Mathematics Hunan UniversityChangsha410082China

A classical result of Motzkin and Straus established the connection between the Lagrangian of a graph and its maximum *** it,they gave a new proof of Turán’s *** aroused the interests in studying the connection between continuous optimization and extremal problems in *** 2009,*** Bulòand *** extended the result of Motzkin-Straus to r-uniform ***,Johnston and Lu initiated the study of the Turán density of a non-uniform *** optimization problems related to several types of non-uniform hypergraphs and its applications on Turán densities have also been *** this paper,we obtain a Motzkin-Straus type of results for all non-uniform *** it,we give an upper bound of the Turán density of a complete non-uniform hypergraph.

关键词： hypergrapli maximum clique polynomial optimization

For Mega-Constellations: Edge Computing and Safety Management Based on Blockchain Technology

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China Communications 2024年第2期21卷 59-73页

作者： Zhen Zhang bing guo Chengjie Li College of Computer Science Sichuan UniversityChengdu 610064China The Key Laboratory for Computer Systems of State Ethnic Affairs Commission School of Computer Science and TechnologySouthwest Minzu UniversityChengdu 610225China National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of ChinaChengdu 611731China

In mega-constellation Communication Systems, efficient routing algorithms and data transmission technologies are employed to ensure fast and reliable data transfer. However, the limited computational resources of satellites necessitate the use of edge computing to enhance secure *** edge computing reduces the burden on cloud computing, it introduces security and reliability challenges in open satellite communication channels. To address these challenges, we propose a blockchain architecture specifically designed for edge computing in mega-constellation communication systems. This architecture narrows down the consensus scope of the blockchain to meet the requirements of edge computing while ensuring comprehensive log storage across the network. Additionally, we introduce a reputation management mechanism for nodes within the blockchain, evaluating their trustworthiness, workload, and efficiency. Nodes with higher reputation scores are selected to participate in tasks and are appropriately incentivized. Simulation results demonstrate that our approach achieves a task result reliability of 95% while improving computational speed.

关键词： blockchain consensus mechanism edge computing mega-constellation reputation management

Micro/nano Indentation and Single Grit Diamond Grinding Mechanism on Ultra Pure Fused Silica

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Chinese Journal of Mechanical Engineering 2011年第6期24卷 963-970页

作者： ZHAO Qingliang guo bing STEPHENSIN David CORBETT John School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China Materials Department Cranfield University Cranfield Bedford MK43 OAL UK School of Applied Sciences Cranfield University Cranfield Bedford MK43 OAL UK

The existing research about ductile grinding of fused silica glass was mainly focused on how to carry out ductile regime material removal for generating very ＂smoothed＂ surface and investigate the machining-induced damage in the grinding in order to reduce or eliminate the subsurface *** brittle/ductile transition behavior of optical glass materials and the wear of diamond wheel are the most important factors for ductile grinding of optical *** this paper,the critical brittle/ductile depth,the influence factors on brittle/ductile transition behavior,the wear of diamond grits in diamond grinding of ultra pure fused silica（UPFS） are investigated by means of micro/nano indentation technique,as well as single grit diamond grinding on an ultra-stiff machine tool,Tetraform ＂C＂.The single grit grinding processes are in-process monitored using acoustic emission（AE） and force dynamometer *** wear of diamond grits,morphology and subsurface integrity of the machined groves are examined with atomic force microscope（AFM） and scanning electron microscope（SEM）.The critical brittle/ductile depth of more than 0.5 μm is *** compared to the using roof-like grits,by using pyramidal diamonds leads to higher critical depths of scratch with identical grinding ***,the influence of grit shapes on the critical depth is not significant as *** grinding force increased linearly with depth of cut in the ductile removal regime,but in brittle removal regime,there are large fluctuations instead of forces *** SEM photographs of the cross-section profile show that the median cracks dominate the crack patterns beneath the single ***,The SEM photographs show multi worn patterns of diamond grits,indicating an inhomogeneous wear mechanism of diamond grits in grinding of fused silica with diamond grinding *** proposed research provides the basal technical theory for improving the ultra-precision grinding of UPFS.

关键词： ultra pure fused silica (UPFS) micro/nano indentation single grit diamond grinding ductile material removal subsurface integrity diamond grits wear

A new monitoring index for ecological vulnerability and its application in the Yellow River Basin,China from 2000 to 2022

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Journal of Arid Land 2024年第9期16卷 1163-1182页

作者： guo bing XU Mei ZHANG Rui LUO Wei School of Civil Engineering and Geomatics Shandong University of TechnologyZibo 255000China Key Laboratory of Remote Sensing of Gansu Province Heihe Remote Sensing Experimental Research StationNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China North China Institute of Aerospace Engineering Langfang 065000China

The ecological environment of the Yellow River Basin has become more fragile under the combined action of natural and manmade ***,the change mechanisms of ecological vulnerability in different sub-regions and periods vary,and the reasons for this variability are yet to be ***,in this study,we proposed a new remote sensing ecological vulnerability index by considering moisture,heat,greenness,dryness,land degradation,and social economy indicators and then analyzed and disclosed the spatial and temporal change patterns of ecological vulnerability of the Yellow River Basin,China from 2000 to 2022 and its driving *** results showed that the newly proposed remote sensing ecological vulnerability index had a high accuracy,at 86.36%,which indicated a higher applicability in the Yellow River *** 2000 to 2022,the average remote sensing ecological vulnerability index of the Yellow River Basin was 1.03,denoting moderate vulnerability *** intensive vulnerability area was the most widely distributed,which was mostly located in the northern part of Shaanxi Province and the eastern part of Shanxi *** 2000 to 2022,the ecological vulnerability in the Yellow showed an overall stable trend,while that of the central and eastern regions showed an obvious trend of *** gravity center of ecological vulnerability migrated southwest,indicating that the aggravation of ecological vulnerability in the southwestern regions was more severe than in the northeastern regions of the *** dominant single factor of changes in ecological vulnerability shifted from normalized difference vegetation index(NDVI)to temperature from 2000 to 2022,and the interaction factors shifted from temperature∩NDVI to temperature∩precipitation,which indicated that the global climate change exerted a more significant impact on regional *** above results could provide decision support for the ecological protection and restoration of the Y

关键词： ecological vulnerability spatio-temporal pattern gravity center migration trajectory interaction factors geodetector green index q-value

Pilot protection of hybrid MMC DC grid based on active detection

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Protection and Control of Modern Power Systems 2020年第1期5卷 82-96页

作者： guobing Song Junjie Hou bing guo Zhehong Chen School of Electrical Engineering Xi’an Jiaotong UniversityXi’an 710049China

Considering the advantages and limitations of traditional identification method,combined with the strategy of active detection,the principle of DC grid pilot protection based on active detection is proposed to improve the sensitivity and reliability of hybrid MMC DC grid protection,and to ensure the accurate identification of fault areas in DC *** using the DC fault ride-through control strategy of the hybrid sub-module MMC,the fault current at the converter station DC terminal is *** on the high controllability of hybrid MMC,sinusoidal fault detection signals with the same frequency are injected into the line at each converter *** on model recognition,the capacitance model condition is satisfied by the detected signals at both ends during external faults whereas not satisfied during internal *** Spearman correlation coefficients is then introduced,and the correlation discriminant of capacitance model is constructed to realize fault area discrimination of DC *** simulation results show that the active detection protection scheme proposed in this paper can accurately identify the fault area of DC grid,and is not affected by fault impedance and has low sampling rate requirement.

关键词： Hybrid MMC DC grid Fault ride-through control strategy Active detection Model recognition Pilot protection

An estimation method of soil wind erosion in Inner Mongolia of China based on geographic information system and remote sensing

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Journal of Arid Land 2015年第3期7卷 304-317页

作者： Yi ZHOU bing guo ShiXin WANG HePing TAO Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences University of Chinese Academy of Sciences Institute of Mountain Hazards and Environment Chinese Academy of Sciences

Studies of wind erosion based on Geographic Information System（GIS） and Remote Sensing（RS） have not attracted sufficient attention because they are limited by natural and scientific *** studies have been conducted to estimate the intensity of large-scale wind erosion in Inner Mongolia,*** the present study,a new model based on five factors including the number of snow cover days,soil erodibility,aridity,vegetation index and wind field intensity was developed to quantitatively estimate the amount of wind *** results showed that wind erosion widely existed in Inner *** covers an area of approximately 90×104 km2,accounting for 80% of the study *** 1985–2011,wind erosion has aggravated over the entire region of Inner Mongolia,which was indicated by enlarged zones of erosion at severe,intensive and mild *** Inner Mongolia,a distinct spatial differentiation of wind erosion intensity was *** distribution of change intensity exhibited a downward trend that decreased from severe increase in the southwest to mild decrease in the northeast of the *** occupied by barren land or sparse vegetation showed the most severe erosion,followed by land occupied by open *** would have the most dramatic potential for changes in the future because these areas showed the largest fluctuation range of change *** addition,a significantly negative relation was noted between change intensity and land *** relation between soil type and change intensity differed with the content of Ca CO3 and the surface composition of sandy,loamy and clayey soils with particle sizes of 0–1 *** results have certain significance for understanding the mechanism and change process of wind erosion that has occurred during the study ***,the present study can provide a scientific basis for the prevention and treatment of wind erosion in Inner Mongolia.

关键词： wind erosion estimation model soil erodibility snow cover days aridity Inner Mongolia

Deformation Analysis of Micro/Nano Indentation and Diamond Grinding on Optical Glasses

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Chinese Journal of Mechanical Engineering 2012年第3期25卷 411-418页

作者： ZHAO Qingliang ZHAO Lingling guo bing STEPHENSIN David CORBETT John School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China Materials Department Cranfield UniversityCranfieldBedford MK43 OALUK School of Applied Sciences Cranfield UniversityCranfieldBedford MK43 OALUK

The previous research of precision grinding optical glasses with electrolytic in process dressing （ELID） technology mainly concentrated on the action of ELID and machining parameters when grinding, which aim at generating very ＂smoothed＂ surfaces and reducing the subsurface damage. However, when grinding spectrosil 2000 and BK7 glass assisted with ELID technology, a deeply comparative study on material removal mechanism and the wheel wear behaviors have not been given yet. In this paper, the micro/nano indentation technique is initially applied for investigating the mechanical properties of optical glasses, whose results are then refereed to evaluate the machinability. In single grit diamond scratching on glasses, the scratching traces display four kinds of scratch characteristics according to different material removal modes. In normal grinding experiments, the result shows BK7 glass has a better machinability than that of spectrosil 2000, corresponding to what the micro/nano indentation vent revealed. Under the same grinding depth parameters, the smaller amplitude of acoustic emission （AE） raw signals, grinding force and grinding force ratio correspond to a better surface quality. While for these two kinds of glasses, with the increasing of grinding depth, the variation trends of the surface roughness, the force ratio, and the AE raw signals are contrary, which should be attributed to different material removal modes. Moreover, the SEM micrographs of used wheels surface indicate that diamond grains on the wheel surface after grinding BK7 glass are worn more severely than that of spectrosil 2000. The proposed research analyzes what happened in the grinding process with different material removal patterns, which can provide a basis for producing high-quality optical glasses and comprehensively evaluate the surface and subsurface integrity of optical glasses.

关键词： optical glasses micro/nano indentation single grit diamond scratching material removal mode surface integrity electrolytic in process dressing (ELID)

Ramsey Numbers of Trees Versus Multiple Copies of Books

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 600-612页

作者： Xiao-bing guo Si-nan HU Yue-jian PENG School of Mathematical Sciences Luoyang Normal UniversityLuoyang 471934China School of Mathematics Hunan UniversityChangsha 410082China

Given two graphs G and H,the Ramsey number R(G,H) is the minimum integer N such that any two-coloring of the edges of K_(N) in red or blue yields a red G or a blue *** v(G) be the number of vertices of G and χ(G) be the chromatic number of *** s(G) denote the chromatic surplus of G,the number of vertices in a minimum color class among all proper χ(G)-colorings of *** showed that R(G,H)≥(v(G)-1)(χ(H)-1)+s(H) if G is connected and v(G)≥s(H).A connected graph G is H-good if R(G,H)=(v(G)-1)(χ(H)-1)+s(H).Let tH denote the disjoint union of t copies of graph H,and let G∨H denote the join of G and *** a complete graph on n vertices by K_(n),and a tree on n vertices by T_(n).Denote a book with n pages by B_(n),i.e.,the join K_(2) ∨■.Erd?s,Faudree,Rousseau and Schelp proved that T_(n) is B_(m)-good if n≥*** this paper,we obtain the exact Ramsey number of T_(n) versus 2B_(2).Our result implies that T_(n) is 2B_(2)-good if n≥5.

关键词： ramsey number ramsey goodness tree book