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Some recent developments in modeling quantile treatment effects

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Applied Mathematics(A Journal of Chinese Universities) 2020年第2期35卷 220-243页

作者： tang sheng-fang Department of Statistics School of EconomicsXiamen UniversityXiamen 361005China

This paper provides a selective review of the recent developments on econometric/statistical modeling in quantile treatment effects under both selection on observables and on ***,we discuss identification,estimation and inference of quantile treatment effects under the framework of selection on ***,we consider the case where the treatment variable is endogenous or self-selected,for which an instrumental variable method provides a powerful tool to tackle this ***,some extensions are discussed to the data-rich environments,to the regression discontinuity design,and some other approaches to identify quantile treatment effects are also *** particular,some future research works in this area are addressed.

关键词： average treatment effect endogeneity quantile treatment effect regression discontinuity design

Quantum Wavefunctions and Fluctuations of Mesoscopic RLC Circuit

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Chinese Physics Letters 2000年第7期17卷 528-529页

作者： WANG Ji-Suo LIU tang-Kun ZHAN ming-sheng State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071 Laser Spectroscopy Laboratory Anhui Institute of Optics and Fine MechanicsChinese Academy of SciencesHefei 230031 Department of Physics Liaocheng Teachers UniversityLiaocheng 252059 Department of Physics Hubei Normal UniversityHuangshi 435002

The quantum wavefunctions and the corresponding energy levels of a RLC (Resistance-Inductance-Capacity) electric circuit are obtained by using canonical quantization method and unitary transformation from the classical equation of motion. The quantum fluctuations of charge and current in an arbitrary eigenstate of the system have also been given as wellas the uncertainty relation. It is showed that even if at 0 K charge and current in the circuit exhibit quantum fluctuations, which originates from fluctuations of zero point vibrations of the system.

关键词： motion quantum charge

P-and SV-wave dispersion and attenuation in saturated microcracked porous rock with aligned penny-shaped fractures

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Petroleum Science 2024年第1期21卷 143-161页

作者： sheng-Qing Li Wen-Hao Wang Yuan-Da Su Jun-Xin Guo Xiao-ming tang School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Laoshan National Laboratory Qingdao 266071ShangdongChina Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology Southern University of Science and TechnologyShenzhen 518055GuangdongChina Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055GuangdongChina

P-and SV-wave dispersion and attenuation have been extensively investigated in saturated poroelastic media with aligned ***,there are few existing models that incorporate the multiple wave attenuation mechanisms from the microscopic scale to the macroscopic ***,in this work,we developed a unified model to incorporate the wave attenuation mechanisms at different scales,which includes the microscopic squirt flow between the microcracks and pores,the mesoscopic wave-induced fluid flow between fractures and background(FB-WIFF),and the macroscopic Biot's global flow and elastic scattering(ES)from the *** tang's modified Biot's theory and the mixed-boundary conditions,we derived the exact frequency-dependent solutions of the scattering problem for a single penny-shaped fracture with oblique incident P-and *** then developed theoretical models for a set of aligned fractures and randomly oriented fractures using the Foldy *** results indicated that microcrack squirt flow considerably influences the dispersion and attenuation of P-and SV-wave *** coupling effects of microcrack squirt flow with the FB-WIFF and ES of fractures cause much higher velocity dispersion and attenuation for P waves than for SV *** oriented fractures substantially reduce the attenuation caused by the FB-WIFF and ES,particularly for the ES attenuation of SV *** a comparison with existing models in the limiting cases and previous experimental measurements,we validated our model.

关键词： Aligned fractures P-and SV-wave Dispersion and attenuation Microcracked porous background FB-WIFF Elastic scattering Squirt flow

Sensitivity function analysis of gravitational wave detection with single-laser and large-momentum-transfer atomic sensors

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Research in Astronomy and Astrophysics 2015年第3期15卷 333-347页

作者： Biao tang Bao-Cheng Zhang Lin Zhou Jin Wang ming-sheng Zhan State Key Laboratory of Magnetic Resonances and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences University of Chinese Academy of Sciences

Recently, a configuration using atomic interferometers （AIs） had been sug- gested for the detection of gravitational waves. A new AI with some additional laser pulses for implementing large momentum transfer was also put forward, in order to reduce the effect of shot noise and laser frequency noise. We use a sensitivity function to analyze all possible configurations of the new AI and to distinguish how many mo- menta are transferred in a specific configuration. By analyzing the new configuration, we further explore a detection scheme for gravitational waves, in particular, that ame- liorates laser frequency noise. We find that the amelioration occurs in such a scheme, but novelly, in some cases, the frequency noise can be canceled completely by using a proper data processing method.

关键词： gravitational wave detection -- atomic interferometer-- laser frequencynoise

Effect of hydroxyapatite nanoparticles on the growth and p53/c-Myc protein expression of implanted hepatic VX_2 tumor in rabbits by intravenous injection

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World Journal of Gastroenterology 2007年第20期13卷 2798-2802页

作者： Jun Hu Zhi-Su Liu sheng-Li tang Yue-ming He Department of General Surgery Zhongnan Hospital Wuhan University Wuhan 430071

AIM： To evaluate the effect of hydroxyapatite nano- particles （Nano HAP） by intravenous injection on the inhibition of implanted hepatic VX2 tumor growth in rabbits and cell p53/c-Myc protein expression. METHODS： 60 hepatic VX2 tumor-bearing rabbits was randomly divided into five groups. Nano HAP collosol 20 mglkg, 40 mg/kg, 5-FU solutions 20 mg/mL, mixed liquor of 5-FU solution 20 mg/mL and Nano HAP collosol 20 mg/kg were infused by vein, normal saline conducted as the control. The general state, weight, liver function and gross tumor volume were detected dynamically. The expression of p53 and c-Myc gene protein in tumor tissue was detected by immunohistochemistry methods. RESULTS： The growth of implanted hepatic VX2 tumors was significantly inhibited in all therapy groups, 3 wk after the injection, the tumor control rates in Nano HAP collosol groups were 25.5% and 32.5% respectively, and the gross tumor volumes were obviously less than that of control group. （24.81 ± 5.17 and 22.73 ± 4.23 vs 33.32 ± 5.26, P 〈 0.05）. The tumor control rate of 5-FU group was 43.7% （18.74 4± 4.40 vs 33.32 ± 5.26, P 〈 0.05）, but the general state of the animals after injection aggravated; and the adverse reaction in the drug combination group obviously decreased. Due to the effect of Nano HAP, the positive expression of tumor associated the mutated p53 and c-Myc in tumor tissue was decreased obviously compared with the control group. CONCLUSION： Nano HAP has evident inhibitory action on rabbit implanted hepatic VX2 tumor in vivo, which may be the result of decreasing the expression of the mutated p53 and c-myc, and drug combination can obviously decrease the adverse reaction of 5-FU.

关键词： Hydroxyapatite nanoparticles Rabbit VX2 Liver carcinoma p53 c-myc

Global Dynamic Responses and Progressive Failure of Submerged Floating Tunnel Under Cable Breakage Conditions

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China Ocean Engineering 2024年第4期38卷 676-688页

作者： ZHOU Xiang-bo QIAO Dong-sheng WANG ming tang Guo-qiang LU Lin OU Jinping State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

The Submerged Floating Tunnel(SFT)relies on a tensioned mooring system for precise *** sudden breakage of a single cable can trigger an immediate alteration in the constraint conditions of the tube,inducing a transient heave response within the structure along with a transient increase in cable tension experienced by adjacent *** more severe cases,this may even lead to a progressive failure culminating in the global destruction of the *** study used ANSYS/AQWA to establish a numerical model of the entire length SFT for the hydrodynamic response analysis,and conducted a coupled calculation of the dynamic responses of the SFT-mooring line model based on Orca Flex to study the global dynamic responses of the SFT at the moment of cable breakage and the redistribution of cable internal *** most unfavorable position for SFT cable breakage was identified,the influence mechanism of cable breakage at different positions on the global dynamic response was revealed,and the progressive chain failure pattern caused by localized cable breakage are also clarified.

关键词： submerged floating tunnel cable breakage global dynamic responses progressive failure

Influences of Alloying Elements on Oxidation Behavior of Steels and Microstructure of Oxide Scales

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Journal of Iron and Steel Research International 2016年第3期23卷 231-237页

作者： Hui-bin WU Di WANG Peng-cheng ZHANG Jin-ming LIANG sheng LIU Di tang National Engineering Research Center for Advanced Rolling Technology University of Science and Technology Beijing

In order to figure out the oxidation behavior of steels during heating,five micro-alloyed steels were subjected to continuous and isothermal oxidation using the thermo gravimetric analyzer and the Gleeble-3500thermo-mechanical *** microstructure of oxide scales,especially the thickness fractions of Fe2O3,Fe3O4 and FeO layers,was analyzed using the scanning electron microscope（SEM）,electron probe microanalyzer（EPMA）and electron backscattered diffraction（EBSD）*** micro-alloyed steels containing alloying elements（Si,Cr,Ni and Cu）show a higher oxidation resistance compared with the low carbon *** is found that alloying elements accumulated at scale/substrate interface during high temperature *** elements function in two ways in the oxidation of steels：one is enhancing the scale/substrate interface and consequently suppressing the blister of scales;and the other is impeding the outward diffusion of iron cations from substrate to scales,resulting in the decrease of oxidation *** the diffusion of iron cations is impeded,the thickness fractions of Fe2O3 and Fe3O4of micro-alloyed steels are more than those of low carbon steels.

关键词： micro-alloyed steel high temperature oxidation oxidation kinetics microstructure oxide scale

Electric transport properties and temperature stability of magnetoresistance of composite system between La_(8/9)Sr_(1/45)Na_(4/45)MnO_3 and Sb_2O_3

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Rare Metals 2013年第4期32卷 363-368页

作者： Gui-Ying Wang Yong-Gang tang Qi-Xiang Song ming-Yu Zhang Zhen-sheng Peng Anhui Key Laboratory of Spintronic and Nano-materials Research School of Mechanical and Electronic Engineering Suzhou University

The samples ofLa8/9Sr1/45Na4/45MnO3 （LSNMO）/x/2（Sb2O3） were prepared by the solid-state reaction method. The electric transport properties and the temperature stabil-ity of magnetoresistance （MR） of the samples were studied through the measurements of X-ray diffraction patterns, resistivity-temperature （ρ-T） curves, mass magnetization-temperature （σ-T） curves, and magnetoresistance-temper-ature （MR-T） curves. The results indicate that the p-Tcurves of the original material LSNMO show two peaks, and the phenomenon of two peaks of ρ-T curves disappears for the composite samples, which can be explained by a competition between surface-phase resistivity induced by boundary-dependent scattering and body-phase resistivity induced by paramagnetism-ferromagnetism transition. For all the sam-ples in the low temperature range, MR increases continu-ously with the decrease of temperature, which shows a characteristic of low-field magnetoresistance. However, MR basically keeps the same in the high temperature range. The paramagnetism-ferromagnetism transition is observed in the high temperature range due to a composite between perov-skite manganite and insulator, which can enhance the tem-perature of MR appearance in the high temperature range and make it to appear near room temperature. For the sample with x = 0.12, MR remains constant at the value of 7.5 % in the temperature range of 300-260 K, which achieves a tem-perature stability of MR near room temperature. In addition,for the sample with x = 0.16, MR is above 6.8 % in the high temperature range of 318-252 K （△T = 66 K）. MR almost remains constant in this temperature range, which favors the practical application of MR.

关键词： Electric transport property Temperaturestability of magnetoresistance Two-phase composite Perovskite manganite

Fractal Feature of Western Fracture Zone in Xikuangshan Antimony Mine and its Geological Significance

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Journal of Central South University 2000年第4期12卷 212-215页

作者： tang Shi-jia GAO Guang-ming PENG En-sheng SUN Zhen-jia College of Resources Environment and Civil EngineeringCentral South UniversityChangsha 410083China

In Xikuangshan antimony ore-field, the western fracture zone is a composite of major fault, F75, and its secondary faults, such as F71, F72 and F3 etc.. On plane, the fracture zone scatters from southwest to northeast, and concentrates from upper to deeper level on profile. All ore-bodies exist in the carbonate of footwall of the major fault or that of the footwall of its secondary faults. From 480 m and 320 m to 120 m level, the fractal dimensional number of the fault system decreases from 1.482 2 and 1.448 6 to 1.339 2, which indicates the form of fracture zone becoming more simple at deeper level. And in five sub-ranges, the III and IV sub-ranges are the known area, and the I, II and V sub-ranges are unknown. The fractal studies of the western fracture zone in these sub-ranges show that the fractal dimensional numbers of the I and II, being 1.201 5 and 1.278 0, respectively, are smaller than that of the III and IV, being 1.475 9 and 1.576 9, respectively; and that of the V, being 1.571 2, keeps with that of the III, IV sub-ranges. So mineralization is not well in I and II sub-ranges, and V sub-range is the best to benefit mineralization.

关键词： fractal fractal dimension fracture zone Xikuangshan antimony-mine