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Acta Mathematica Sinica,English Series 2024年第8期40卷 1850-1874页

作者： Chun mao huang Rui ZHANG Zhi Qiang GAO Department of Mathematics Harbin Institute of Technology(Weihai)Weihai 264209P.R.China School of Mathematical Sciences Beijing Normal UniversityBeijing 100875P.R.China

Let(Zn)be a supercritical branching process with immigration in an independent and identically distributed random *** necessary moment conditions,we show the exact convergence rate in the central limit theorem on log Zn and establish the corresponding local limit theorem by using the moments of the natural submartingale and the convergence rates of its *** similar approach and with the help of a change of measure,we also present the so-called integrolocal theorem and integral large deviation theorem to characterize the precise asymptotics of the upper large deviations.

关键词： Branching process with immigration random environment central limit theorem large deviation

Laboratory investigation on relationship between degree of saturation, B-value and P-wave velocity

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Journal of Central South University 2013年第7期20卷 2001-2007页

作者： GU Xiao-qiang YANG Jun huang mao-song Department of Geotechnical Engineering Tongji University Shanghai 200092 China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education (Tongji University) Shanghai 200092 China Department of Civil Engineering The University of Hong Kong Hong Kong China

Laboratory tests were performed on Toyoura sand specimens to investigate the relationship between degree of saturation Sr, B-value and P-wave velocity Vp. Different types of pore water （de-aired water or tap water） and pore gas （air or CO2） as well as different magnitudes of back pressure were used to achieve different Sr （or B-value）. The measured relationship between B-value and Vp was not consistent with the theoretical prediction. The measurement shows that the Vp value in the specimen flushed with de-aired water is independent of B-value （or St） and is always around the one in fully saturated condition. However, the Vp value in the specimen flushed with tap water increases with B-value, but the shape of the relationship between Vp and B-value is quite different from the theoretical prediction. The possible explanation for the discrepancy between laboratory measurement and theoretical prediction lies in that the air exists in the water as air bubbles and therefore the pore fluid （air-water mixture） is heterogeneous instead of homogenous assumed in the theoretical prediction.

关键词： degree of saturation B-value P-wave velocity bender element

Simulations of ultra-long wavelength interferometers in Earth orbit and on the lunar surface

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Research in Astronomy and Astrophysics 2015年第3期15卷 443-452页

作者： Mo Zhang mao-Hai huang Yi-Hua Yan Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of Sciences Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences

We present simulations of interferometers in Earth orbit and on the lunar surface to guide the design and optimization of space-based ultra-long wavelength missions, such as those pioneered by China＇s Chang＇e Program. We choose parame- ters and present simulations using simulated data to identify inter-dependencies and constraints on science and engineering parameters. A regolith model is created for the lunar surface array simulation, and the results show that the lunar regolith will have an undesirable effect on the observations. We estimate data transmission requirements, calculate sensitivities for both cases, and discuss the trade-off between brightness tem- perature sensitivity and angular resolution for the Earth orbit array case.

关键词： techniques: interferometric -- Moon -- methods: data analysis

Collimation of High Velocity Molecular Outflows

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Chinese Physics Letters 1998年第5期15卷 388-390页

作者： WU Yue-fang huang mao-hai Department of Geophysics Peking UniversityBeijing 100871 Department of Astronomy Boston UniversityBostonMA02215U.S.A.

Statistics of apparent collimation factors for molecular outflows catalogued is *** collimation factor is calculated with the project effects *** is collimation difference between high and low mass *** may concern the... 详细信息

关键词： Velocity removed apparent

Anisotropic characteristics of granular materials under simple shear

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Journal of Central South University 2013年第8期20卷 2275-2284页

作者： QIAN Jian-gu YOU Zi-pei huang mao-song Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education (Tongji University) Shanghai 200092 China Department of Geotechnical Engineering Tongji University Shanghai 200092 China

The discrete element method was used to investigate the microscopic characteristics of granular materials under simple shear loading conditions. A series of simple tests on photo-elastic materials were used as a benchmark. With respect to the original experimental observations, average micro-variables such as the shear stress, shear strain and the volumetric dilatancy were extracted to illustrate the performance of the DEM simulation. The change of anisotropic density distributions of contact normals and contact forces was demonstrated during the course of simple shear. On the basis of microscopic characteristics, an analytical approach was further used to explore the macroscopic behaviors involving anisotropic shear strength and anisotropic stress-dilatancy. This results show that under simple shear loading, anisotropic shear strength arises primarily due to the difference between principal directions of the stress and the fabric. In addition, non-coaxiality, referring to the difference between principal directions of the strain rate and the stress, generates less stress-dilatancy. In particular, the anisotropic hardening and anisotropic stress-dilatancy will reduce to the isotropic hardening and the classical Taylor’s stress-dilatancy under proportional loading.

关键词： simple shear discrete element method anisotropy non-coaxiality

A SCINTILLATOR-OPTICAL FIBER SYSTEM FOR VACUUM ULTRAVIOLET(VUV)SPECTROSCOPIC MEASUREMENT

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Chinese Physics Letters 1989年第1期6卷 47-48页

作者： LI Zanliang WANG Wenshu huang mao Institute of Physics Academia SinicaBeijing Department of Physics Branch School of Peking UniversityBeijing

Spectroscopy of vacuum ultraviolet(VUV)radiation emitted by intrinsic and injected impurities in tokamak plasma is an important plasma diagnostic *** information of impurity concentration,radiation loss,the effective ion charge(z_(eff)),particle transport and other quantities which may affect the behavior of the discharge can be obtained from the measurements of VUV line radiation.

关键词： VUV quantities vacuum

Evaluation on interactive visualization data with scatterplots

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Visual Informatics 2020年第4期4卷 1-10页

作者： Quang Vinh Nguyen Natalie Miller David Arness Weidong huang mao Lin huang Simeon Simoff MARCS Institute Western Sydney UniversityAustralia School of Computer Data and Mathematical SciencesWestern Sydney UniversityAustralia School of Psychology Western Sydney UniversityAustralia Faculty of Transdisciplinary Innovation University of TechnologySydneyAustralia School of Software Faculty of Engineering&ITUniversity of TechnologySydneyAustralia

Scatterplots and scatterplot matrix methods have been popularly used for showing statistical graphics and for exposing patterns in multivariate data.A recent technique,called Linkable Scatterplots,provides an interesting idea for interactive visual exploration which provides a set of necessary plot panels on demand together with interaction,linking and *** article presents a controlled study with a mixed-model design to evaluate the effectiveness and user experience on the visual exploration when using a Sequential-Scatterplots who a single plot is shown at a time,Multiple-Scatterplots who number of plots can be specified and shown,and Simultaneous-Scatterplots who all plots are shown as a scatterplot *** from the study demonstrated higher accuracy using the Multiple-Scatterplots visualization,particularly in comparison with the *** the time taken to complete tasks was longer in the Multiple-Scatterplots technique,compared with the simpler Sequential-Scatterplots,Multiple-Scatterplots is inherently more ***,the Multiple-Scatterplots technique is the most highly preferred and positively experienced technique in this ***,results support the strength of Multiple-Scatterplots and highlight its potential as an effective data visualization technique for exploring multivariate data.

关键词： Multivariate data visualization Multidimensional data visualization Scatterplots Scatterplot matrix Controlled study

Discrete numerical modeling of granular materials considering crushability

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Journal of Mountain Science 2017年第4期14卷 758-770页

作者： QIAN Jian-gu GU Jian-bo GU Xiao-qiang huang mao-song Key Laboratory of Geotechnieal and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

The aim of this study is to numerically investigate the influence of particle breakage on the mechanical behavior of granular materials using a discrete element method(DEM). To enable particle crushing, non-crushable elementary particles are boned together to represents the granular aggregates which can be crushed when the external force exceeds its strength. The flaw of the aggregate was also modeled by randomly distributed void. Single particle crushing tests were carried out to determine the distribution of particle strength. The results of single particle crushing tests illustrate that the simulated single particle fracture strength and pattern agree well with the Weibull's distribution *** oedometer tests, drained monotonic and cyclic triaxial tests were also carried out to investigate the crushing of the aggregates and the associated mechanical behaviors. The effect of confining pressure on the crushing of aggregates and the mechanical behavior was also analyzed. It was found that the peak stress and dilation decrease significantly when particle crushing was *** deformation behavior of the specimen is essentially controlled by two factors: particle rearrangement-induced dilation and particle crushing-induced contraction. The increase of permanent strain and the reduction of dilation were observed during cyclic loading and they tend to reach a stable state after a certain number of cycles. The crushing of aggregate is most significant in the first two cycles. The results also indicated that for the same axial strain the volumetric strain and the bound breakage in the cyclic loading tests are significantly larger than that in the monotonic loading tests,especially at high cyclic stress ratio.

关键词： DEM simulation Granular materials Crushing Monotonic and Cyclic triaxial test

Thoughts on Traditional Chinese Medicine Treatment of Novel Coronavirus Pneumonia Based on Two Cases

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Chinese Journal of Integrative Medicine 2021年第5期27卷 375-378页

作者： MA Jie WU Hua-yang CHEN Yu-zhu huang mao ZHANG Li-shan Department of Respiratory Medicine Beijing Hospital of Integrated Traditional Chinese and Western MedicineBeijing 100039China Department of Respiratory Medicine Dongzhimen Hospital Affiliated to Beijing University of Chinese MedicineBeijing 100700China Department of Traditional Chinese Medicine Beijing Jingmei Group General HospitalBeijing 102300China

Since December 2019,cases of unexplained pneumonia have been found in Wuhan,Hubei Province,*** scholars have identified the disease as caused by a new type of *** disease is categorized as a plague in Chinese medicine... 详细信息

关键词： Wuhan Hubei Corona

Stability control of gate groups in deep wells

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Mining Science and Technology 2009年第2期19卷 155-160页

作者： GUO Zhi-biao GUO Ping-ye huang mao-hong LIU Yin-gen School of Geotechnical Engineering China University of Mining ＆ Technology Beijing 100083 China Xuzhou Mine Group Company Xuzhou Jiangsu 221167 China

In order to study stability control methods for a deep gate group under complex stresses,we conducted field investigations and analyses of reasons for damage in the Xuzhou mining *** reasons are proposed:deep high stress,improper roadway layout and support *** stability control countermeasures of the gate group consist of an intensive design technology and responding bolt-mesh-anchor truss support *** research method has been applied at the -1000 m level gate group in Qishan Coal *** countermeasures have been tested by field monitoring.

关键词： deep gate group stability intensive design bolt-mesh-anchor truss support