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International Journal of Mining Science and Technology 2023年第8期33卷 963-976页

作者： Junhao Zhong xiaoli yang School of Civil Engineering Central South UniversityChangsha 410075China

The face stability problem is a major concern for tunnels excavated in rock masses governed by the Hoek-Brown strength *** provide an accurate prediction for the theoretical solution of the critical face pressure,this study adopts the piecewise linear method(PLM)to account for the nonlinearity of the strength envelope and proposes a new multi-horn rotational mechanism based on the Hoek-Brown strength criterion and the associative flow *** analytical solution of critical support pressure is derived from the energy-work balance equation in the framework of the plastic limit theorem;it is formulated as a multivariable nonlinear optimization problem relying on 2m dependent variables(m is the number of segments).Meanwhile,two classic linearized measures,the generalized tangential technique(GTT)and equivalent Mohr-Coulomb parameters method(EMM),are incorporated into the analysis for ***,the parametric study indicates a significant improvement in support pressure by up to 13%compared with the GTT,and as expected,the stability of the tunnel face is greatly influenced by the rock strength *** stress distribution on the rupture surface is calculated to gain an intuitive understanding of the failure at the limit *** the limit analysis is incapable of calculating the true stress distribution in rock masses,a rough approximation of the stress vector on the rupture surface is *** the end,sets of normalized face pressure are provided in the form of charts for a quick assessment of face stability in rock masses.

关键词： Face stability Piecewise linear method Hoek-Brown strength criterion Multi-horn rotational mechanism Limit analysis

Transverse nonlinear vibrations of a circular spinning disk with a varying rotating speed

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Science China(Physics,Mechanics & Astronomy) 2010年第8期53卷 1536-1553页

作者： ZHANG Wei yang xiaoli College of Mechanical Engineering Beijing University of TechnologyBeijing 100124China

We analyze the transverse nonlinear vibrations of a rotating flexible disk subjected to a rotating point force with a periodically varying rotating speed. Based on Hamilton’s principle, the nonlinear governing equations of motion (coupled equations among the radial, tangential and transverse displacements) are derived for the rotating flexible disk. When the in-plane inertia is ignored and a stress function is introduced, the three nonlinearly coupled partial differential equations are reduced to two nonlinearly coupled partial differential equations. According to Galerkin’s approach, a four-degree-of-freedom nonlinear system governing the weakly split resonant modes is derived. The resonant case considered here is 1:1:2:2 internal resonance and a critical speed resonance. The primary parametric resonance for the first-order sin and cos modes and the fundamental parametric resonance for the second-order sin and cos modes are also considered. The method of multiple scales is used to obtain a set of eight-dimensional nonlinear averaged equations. Based on the averaged equations, using numerical simulations, the influence of different parameters on the nonlinear vibrations of the spinning disk is detected. It is concluded that there exist complicated nonlinear behaviors including the periodic, period-n and multi-pulse type chaotic motions for the spinning disk with a varying rotating speed. It is also found that among all parameters, the damping and excitation have great influence on the nonlinear responses of the spinning disk with a varying rotating speed.

关键词： circular spinning disk transverse nonlinear vibration varying rotating speed chaotic motion

Taming complexity in nonlinear dynamical systems by recycled signal

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Science China(Technological Sciences) 2016年第3期59卷 403-410页

作者： SUN ZhongKui yang xiaoli XU Wei Department of Applied Mathematics Northwestern Polytechnical University College of Mathematics and Information Science Shaanxi Normal University

In this paper, the impacts of the recycled signal on the dynamic complexity have been studied theoretically and numerically xn a prototypical nonlinear dynamical system. The Melnikov theory is employed to determine the critical boundary, and the sta- tistical complexity measure （SCM） is defined and calculated to quantify the dynamic complexity. It has been found that one can switch the dynamics from the periodic motion to a chaotic one or suppress the chaotic behavior to a periodic one, merely via adjusting the time delay or the amplitude of the recycled signal, therefore, providing a candidate to tame the dynamic com- plexity in nonlinear dynamical systems.

关键词： recycled signal dynamic complexity SCM

Interpretation of the Minister＇ s Black Veil From Psychoanalysis

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学术界 2016年第7期 295-300页

作者： yang xiaoli School of Foreign Studies Xinjiang Agricultural University Urumchi xinjiang Uygur Autonomous Region 830052

The Minister's Black Veil is one of Hawthorne's most influential short novels. The black veil in it symbolizes the sin. This paper based on the Freudian theory — the three structures of personality: id,ego and superego,is to point out that the process of the minister's wearing the veil is that of the interacting and compromising of the three personalities and that the alienation of the minister's personality is caused by the imbalance of the three personalities.

关键词：部长分析学解读精神相互作用格结构不平衡人格

Control of epileptic activities in a cortex network of multiple coupled neural populations under electromagnetic induction

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Applied Mathematics and Mechanics(English Edition) 2023年第3期44卷 499-514页

作者： Zhongkui SUN Yuanyuan LIU xiaoli yang Wei XU School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an 710129China School of Mathematics and Statistics Shaanxi Normal UniversityXi’an 710062China

Epilepsy is believed to be associated with the abnormal synchronous neuronal activity in the brain,which results from large groups or circuits of *** this paper,we choose to focus on the temporal lobe epilepsy,and establish a cortex network of multiple coupled neural populations to explore the epileptic activities under electromagnetic *** demonstrate that the epileptic activities can be controlled and modulated by electromagnetic induction and coupling among *** certain regions,these two types of control are observed to show exactly reverse *** results show that the strong electromagnetic induction is conducive to eliminating the epileptic *** coupling among regions has a conduction effect that the previous normal background activity of the region gives way to the epileptic discharge,owing to coupling with spike wave discharge ***,these results highlight the role of electromagnetic induction and coupling among the regions in controlling and modulating epileptic activities,and might provide novel insights into the treatments of epilepsy.

关键词： epilepsy electromagnetic induction multiple coupled neural population dynamical transition

The equal-efficiency-proving of fluorescence quenching and enhancement equation

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Chinese Science Bulletin 2005年第22期50卷 2571-2574页

作者： yang Manman XI xiaoli yang Pin College of Chemistry and Chemical Engineering Institute of Molecular Science Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education Shanxi University Taiyuan 030006 China

Through the fluorescence and ultraviolet- visible spectrophotometry we have studied the action of ce- foperazone sodium and worfloxacin, two kinds of medicine with albumin, and examined the equal efficiency quality of fluorescence enhancement and fluorescence quenching equa- tion. The result shows the equal efficiency of calculating dis- sociation constant. In this article, we obtain the dissociation constants of the action of the two kinds of medicine with bo- vine serum albumin, energy- transfer efficiency, the distance of donor-acceptor and quenching constants. The above shows that the action is not caused by dynamic collision but by the binding of medicine and albumin. This article specially points out that the [Mt]/[Pt], which is the ratio of the maxi- mum mol concentration of the quenching agent (medicine) to fluorescent (albumin) mol concentration when the quenching ends, is very important because it is the maximum binding number of quenching agent molecule to a fluorescent mole- cule. There is no more quenching after adding more quench- ing agent beyond this quantity to fluorescent solution. This quantity is determined directly and strictly by experiment, so is also of important significance when discussing quenching efficiency and binding situation of donor-acceptor.

关键词：等效校对荧光性血清白蛋白紫外线照射药理分析

A Survey of Testing for 5G:Solutions,Opportunities,and Challenges

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China Communications 2019年第1期16卷 69-85页

作者： Ping Zhang xiaoli yang Jianqiao Chen Yuzhen Huang State Key Laboratory of Network and Switching Technology Beijing University of Posts and Telecommunications Artificial Intelligence Research Center National Innovation Institute of Defense Technology

With the development of wireless communication technology,the fifth generation mobile communications system(5 G) emerges at a historic moment and devotes itself to open the curtain of the information ***,in order to satisfy the requirement of different applications,various advanced 5 G technologies have been developed in full ***,before applying these 5 G related technologies in practical systems,effective testing methods are needed to evaluate these technologies in a real,comprehensive,rapid and flexible ***,the testing methods are faced with new challenges along with the continuous development of the new 5 G *** this paper,we present a survey of 5 G testing,including solutions and *** particular,two cases are considered,i.e.,channel modelling and overthe-air(OTA) testing of antenna ***,a non-stationary channel model is proposed to characterize and test massive multiple-input multiple-output(MIMO) *** addition,we propose two probe subset selection algorithms for three-dimensional(3 D) OTA testing,which minimizes the number of probe antennas while ensuring the accuracy of the target channel ***,future research directions and challenges on 5 G testing are given.

关键词： 5G testing channel modelling over-the-air testing

Morphologies and Mechanical Properties of Unsaturated Polyester Resin Modified with TDI

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Journal of Wuhan University of Technology(Materials Science) 2008年第4期23卷 460-462页

作者： DUAN Huajun ZHANG Lianmeng WANG Jun yang xiaoli School of Materials Science and Engineering Wuhan University of Technology Wuhan 430070 China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 China

The morphology, mechanical properties of unsaturated polyester（UP） resin modified with TDI were studied via dynamic FT-1R spectra, SEM, DMA and mechanical property testing. Results show that companying with the cured cross-linking reaction of UP resin, TDI can firstly react with UP and produce polyurethane（PU）, and then UP and PU form the cross-linking nets together. The impact fracture section morphology of modified UP resin manifested the typical sea- islands structure. Testing of mechanical properties showes that for introducing of PU, the TDI has an obvious effect on the toughness and strength of UP resin. When the ratio of TDI/UP （w/w） was 7.5%, the modified UP resin exhibited the best mechanical properties with flexural strength of 125 MPa, impact strength of 18 kJ·m^-2 and tensile strength of 72 MPa.

关键词： modified unsaturated polyester TDI morphology toughness mechanical properties

Evaluation of Latest TMPA and CMORPH Precipitation Products with Independent Rain Gauge Observation Networks over High-latitude and Low-latitude Basins in China

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Chinese Geographical Science 2016年第4期26卷 439-455页

作者： JIANG Shanhu REN Liliang YONG Bin HONG yang yang xiaoli YUAN Fei State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University School of Civil Engineering and Environmental Sciences School of Meteorology University of Oklahoma

The Tropical Rainfall Measuring Mission （TRMM） Multi-satellite Precipitation Analysis （TMPA） and National Oceanic and Atmospheric Administration （NOAA） Climate Prediction Center （CPC） morphing technique （CMORPH） are two important multi-satellite precipitation products in TRMM-era and perform important functions in GPM-era. Both TMPA and CMORPH systems simultaneously upgraded their retrieval algorithms and released their latest version of precipitation data in 2013. In this study, the latest TMPA and CMORPH products （i.e., Version-7 real-time TMPA （T-rt） and gauge-adjusted TMPA （T-adj）, and Version- 1.0 real-time CMORPH （C-rt） and Version-l.0 gauge-adjusted CMORPH （C-adj）） are evaluated and intercompared by using independent rain gauge observations for a 12-year （2000--2011） period over two typical basins in China with different geographical and climate conditions. Results indicate that all TMPA and CMORPH products tend to overestimate precipitation for the high-latitude semiarid Laoha River Basin and underestimate it for the low-latitude humid Mishui Basin. Overall, the satellite precipitation products exhibit superior performance over Mishui Basin than that over Laoha River Basin. The C-adj presents the best performance over the high-latitude Laoha River Basin, whereas T-adj showed the best performance over the low-latitude Mishui Basin. The two gauge-adjusted products demonstrate potential in water resource management. However, the accuracy of two real-time satellite precipitation products demonstrates large variability in the two validation basins. The C-rt reaches a similar accuracy level with the gauge-adjusted satellite precipitation products in the high-latitude Laoha River Basin, and T-rt performs well in the low-latitude Mishui Basin. The study also reveals that all satellite precipitation products obviously overestimate light rain amounts and events over Laoha River Basin, whereas they underestimate the amount and events over Mishui Basin. The findings of

关键词： satellite precipitation Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) Cli-mate Prediction Center morphing technique (CMORPH) precision evaluation

Ca-P Conversion Coating on AZ60 Magnesium Alloy for Biomedical Application

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Chemical Research in Chinese Universities 2014年第4期30卷 543-548页

作者： CHENG Zhongji LIAN Jianshe HU xiaoli yang Xiaohong LI Guangyu Key Laboratory of Automobile Materials Ministry of Education College of Materials Science and Engineering Jilin University Changchun 130022 P. R. China

To improve the anti-corrosion behaviors of magnesium alloy in the inner environment of human body,a bioactive Ca-P coating was deposited on the AZ60 magnesium alloy by a novel simple *** morphologies of the Ca-P coatings formed under different treatment time were studied by scanning electron microscopy（SEM）.The corrosion behaviors of Ca-P coating were investigated by electrochemical polarization test and electrochemical impedance spectroscopy in both 3％（mass fraction） NaCl solution and simulated body fluid（SBF）.Immersion test in SBF was performed to evaluate the corrosion rate of Ca-P coated magnesium alloy.X-Ray diffraction（XRD） analysis result shows that the coating mentioned above mainly consists of dicalcium phosphate dehydrate（CaHPO4·2H2O,DCPD） and β-tricalcium phosphate dehydrate[β-TCP,Ca3（PO4）2],which exhibits good corrosion *** magnesium alloy was immersed in 1 mol/L NaOH solution at 80 ℃ for 2 h,hydroxyapatite [Ca10（PO4）6（OH）2,HA]appeared on the magnesium alloy substrate,which can further decrease the corrosion rate of AZ60 magnesium alloy in SBF.

关键词： Ca-P coating Deposited method Magnesium alloy Corrosion rate Simulated body fluid(SBF)