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High-resolution short time interval measurement system implemented in a single FPGA chip

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Chinese Science Bulletin 2011年第12期56卷 1285-1290页

作者： WANG hai ZHANG min LIU Jie Department of Measurement and Control Xidian University Xi' an 710071 China

This study proposes a high-resolution short time interval measurement system based on the Vernier delay line (VDL) method. It should be noted that the programmable delay elements (PDEs) in the Xilinx field programmable gate arrays (FPGAs) provide a novel realization of delay lines. The delay lines can provide an accurate delay difference of 50 ps, which is process, voltage and temperature (PVT) invariant. An excellent consistency for the delay lines can be achieved by adjusting the timing and layout to minimize the measurement errors. The resolution achieved was 58 ps. Experimental results indicate a measurement standard deviation of 36 ps, a differential nonlinearity (DNL) of 36 ps and integral nonlinearity (INL) of 14 ps. The system features high accuracy, easy implementation and low cost.

关键词： FPGA芯片测量系统时间间隔高分辨率现场可编程门阵列 Xilinx 延迟线积分非线性

The influence of female age on male mating preference and reproductive success in cabbage beetle, Colaphellus bowringi

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Insect Science 2014年第4期21卷 515-522页

作者： Xing-Ping Liu hai-min He Fang-Sen Xue Institute of Entomology Jiangxi Agricultural University Nanchang Key Laboratory of Crop Physiology Ecology and GeneticBreeding Nanchang China

The influence of female age on male mating preference and reproductive success has been studied using a promiscuous cabbage beetle, Colaphellus bowringi Baly （Coleoptera： Chrysomelidae）. In a simultaneous choice test, middle-aged females had significantly greater mating success than young and old females. In single pair trials, when paired with middle-aged virgin males, middle-aged females mated faster, copulated longer, and had greater fecundity and fertility than young or old females, while the longevity of males was not significantly affected by female age. This study on C. bowringi suggests that middle-aged females are more receptive to mating, which can result in the highest male reproductive success.

关键词： age behavioral responses Colaphellus bowringi Baly mate preference,reproductive fitness

VIBRATION OF A SINGLE PROTEIN BUBBLE IN BINGHAM LIQUID

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Journal of Hydrodynamics 2009年第5期21卷 658-668页

作者： WANG hai-min JIANG Xu-ping MA Jian-min ZHANG Wen College of Power Engineering University of Shanghai for Science and Technology Shanghai 200093 China Department of Mechanics and Engineering Science Fudan University Shanghai 200433 China

The vibration of a single protein bubble may take place under the action of high pressure difference. In this process, the bubble wall may experience a finite deformation. The equation describing the dynamics of the protein bubble with viscoelastic film in Bingham liquid is derived. A numerical solution to this equation is carried out to study the effect of liquid pressure, the characteristic parameters of Bingham liquid and the viscosity of the protein film on the finite deformation of the bubble. The results show that the vibration of the protein bubble wall is caused by the action of pressure difference, the elastic stress in finite deformation and the dissipation of viscosity of the protein film and Bingham liquid. The vibration is nonlinear. Decreasing the pressure difference between gas and Bingham liquid on both sides of the protein bubble will lead to a change of vibration performance. The frequency and amplitude are reduced, tegether with the speed of vibration damping. In addition, the deformation rate of the bubble is smaller when the amplitude of vibration is reduced, which means shorter time to reach a balance state. On the other side, the increase of the magnitude of viscosity of the protein film or the plastic viscosity of Bingham liquid can restrain the vibration of the protein bubble wall in the course of finite deformation, as a result, the load bearing capacity of bubble is enhanced.

关键词： protein bubble Bingham liquid vibration finite deformation viscosity

The Squeezing Effect in a Mesoscopic RLC Circuit

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Communications in Theoretical Physics 2002年第5期38卷 611-614页

作者： JI Ying-Hua LUO hai-Mei LEI min-Sheng Department of Physics Jiangxi Normal University Nanchang 330027 China Department of Physics Jiangxi Normal University Nanchang 330027 China Department of Physics Jiangxi Normal University Nanchang 330027 China

Using the path integral method we derive quantum wave function and quantum fluctuations of charge andcurrent in the mesoscopic RLC circuit. We find that the quantum fluctuation of charge decreases with time, oppositely,the quantum fluctuation of current increases with time monotonously. Therefore there is a squeezing effect in the *** some more charge devices are used in the mesoscopic-damped circuit, the quantum noise can be reduced. We also findthat uncertainty relation of charge and current periodically varies with the period π/2 in the under-damped case.

关键词： dissipative mesoscopic RLC circuit, quantum fluctuation, squeezing effect

Optical Design of Multilayer Achromatic Waveplate by Simulated Annealing Algorithm

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Chinese Journal of Astronomy and Astrophysics 2008年第3期8卷 349-361页

作者： Jun Ma Jing-Shan Wang Carsten Denker hai-min Wang Big Bear Solar Observatory 40386 North Shore Lane Big Bear City CA 92314 USA New Jersey Institute of Technology Center for Solar-Terrestrial Research 323 Martin Luther Kind Blvd. Newark NJ 07102 USA Astrophysikalisches Institut Potsdam An der Sternwarte 16 D- 14482 Potsdam Germany Currently working at Thorlabs Inc. 435 Route 206 Newton NJ 07860 USA

We applied a Monte Carlo method -- simulated annealing algorithm -- to carry out the design of multilayer achromatic waveplate. We present solutions for three-, six- and ten-layer achromatic waveplates. The optimized retardance settings are found to be 89°51′39″ ± 0°33′37″ and 89°54′46″ ± 0°22′4″ for the six- and ten-layer waveplates, respectively, for a wavelength range from 1000 nm to 1800 nm. The polarimetric properties of multilayer waveplates are investigated based on several numerical experiments. In contrast to previously proposed three-layer achromatic waveplate, the fast axes of the new six- and ten-layer achromatic waveplate remain at fixed angles, independent of the wavelength. Two applications of multilayer achromatic waveplate are discussed, the general-purpose phase shifter and the birefringent filter in the Infrared Imaging Magnetograph （IRIM） system of the Big Bear Solar Observatory （BBSO）. We also checked an experimental method to measure the retardance of waveplates.

关键词： instrumentation spectrographs -- methods numerical -- methods laboratory-- Sun infrared

Adsorption of boron and its relationship with morphologies of TiC

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Rare Metals 2016年第9期35卷 705-710页

作者： hai-min Ding Xiao-Liang Fan Xin-Chun Zhang Ze-You Zheng School of Energy Power and Mechanical Engineering North China Electric Power University

First-principle calculations were performed to study the adsorption of boron and its relationship with the morphologies of Ti *** is found that although the adsorption of boron on all the low-index Ti C crystal planes is thermally favorable,it will be adsorbed more easily by C-terminated {111} and {011} planes,while less possible to be adsorbed by {001}.The study of the formation of B–B clusters indicates that the distribution of boron adatoms on C-terminated（111） and {011} planes will be more uniform,and the diffusion of the adatom further confirms the above *** to the geometry relationship and growth rate of different crystal planes,it is deduced that the adsorption of boron on Ti C will seriously impede the growth of {111} and {011} planes,which can make Ti C grow into hexagonal platelets.

关键词： Ti C Adsorption Surfaces and interfaces First-principle calculations

Calculation of groundwater head distribution with a close barrier during excavation dewatering in confined aquifer

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Geoscience Frontiers 2021年第2期12卷 791-803页

作者： hai-min Lyu Shui-Long Shen Yong-Xia Wu An-Nan Zhou MOE Key Laboratory of Intelligent Manufacturing Technology Department of Civil and Environmental EngineeringCollege of EngineeringShantou UniversityGuangdongChina State Key Laboratory of Internet of Things for Smart City University of MacaoMacaoChina College of Mechanical and Automotive Engineering Shanghai University of Engineering ScienceShanghai201620China Civil and Infrastructure Discipline School of EngineeringRoyal Melbourne Institute of Technology(RMIT)MelbourneVic3001Australia

When pumping is conducted in confined aquifer inside excavation pit(waterproof curtain),the direction of the groundwater seepage outside the excavation changes from horizontal to vertical owing to the existence of the curtain *** is no analytical calculation method for the groundwater head distribution induced by dewatering inside *** paper first analyses the mechanism of the blocking effects from a close barrier in confined ***,a simple equation based on analytical solution is proposed to calculate groundwater heads inside and outside of the excavation pit with waterproof curtain(hereafter refer to close barrier)in a confined *** distribution of groundwater head is derived according to two conditions:(i)pumping with a constant water head,and(ii)pumping with a constant flow *** proposed calculation equation is verified by both numerical simulation and experimental *** comparisons demonstrate that the proposed model can be applied in engineering practice of excavation.

关键词： Confined aquifer Waterproof curtain Dewatering Groundwater head

2D and 3D Palmprint and Palm Vein Recognition Based on Neural Architecture Search

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International Journal of Automation and computing 2021年第3期18卷 377-409页

作者： Wei Jia Wei Xia Yang Zhao hai min Yan-Xiang Chen School of Computer Science and Information Engineering Hefei University of TechnologyHefei 230009China Anhui Province Key Laboratory of Industry Safety and Emergency Technology Hefei 230009China

Palmprint recognition and palm vein recognition are two emerging biometrics *** the past two decades,many traditional methods have been proposed for palmprint recognition and palm vein recognition and have achieved impressive *** recent years,in the field of artificial intelligence,deep learning has gradually become the mainstream recognition technology because of its excellent recognition *** researchers have tried to use convolutional neural networks(CNNs)for palmprint recognition and palm vein ***,the architectures of these CNNs have mostly been developed manually by human experts,which is a time-consuming and error-prone *** order to overcome some shortcomings of manually designed CNN,neural architecture search(NAS)technology has become an important research direction of deep *** significance of NAS is to solve the deep learning model's parameter adjustment problem,which is a cross-study combining optimization and machine *** technology represents the future development direction of deep ***,up to now,NAS technology has not been well studied for palmprint recognition and palm vein *** this paper,in order to investigate the problem of NAS-based 2D and 3D palmprint recognition and palm vein recognition in-depth,we conduct a performance evaluation of twenty representative NAS methods on five 2D palmprint databases,two palm vein databases,and one 3D palmprint *** results show that some NAS methods can achieve promising recognition ***,among different evaluated NAS methods,Proxyless NAS achieves the best recognition performance.

关键词： Performance evaluation neural architecture search biometrics palmprint palm vein deep learning

Biological impact of hepatitis B virus X-hepatitis C virus core fusion gene on human hepatocytes

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World Journal of Gastroenterology 2008年第35期14卷 5412-5418页

作者： Zhen Ma Qin-hai Shen Guo-min Chen Da-Zhi Zhang Institute for Viral Hepatitis Chongqing Medical University Chongqing 400010 China

AIM： To investigate the biological impact of hepatitis B virus X- hepatitis C virus core （HBV X-HCV C） fusion gene on hepatoma cells.METHODS： The recombinant adenoviruses Ad- XC, Ad-X and Ad-C expressing HBV X-HCV C fusion gene, HBVX gene and HCV C gene were constructed, respectively. Hepatoma cells were infected with different recombinant adenoviruses. MTT, colony- forming experiment, FCM, TUNEL assay were performed to observe the biological impact of the HBV X-HCV C fusion aene on liver cells.RESULTS： MTT showed that the Ad-XC group cells grew faster than the other group cells. Colony-forming experiment showed that the colony-forming rate for the Ad-XC group cells was significantly higher than that for the other group cells. FCM analysis showed that Ad-XC/Ad-X/Ad-C infection enhanced the progression of G1→S phase in the HepG2 cell cycle. The apoptosis index of the Ad-XC, Ad-X, Ad-C group cells was significantly lower than that of the AdO and control group cells. Semi-quantitative RT-PCR showed that the expression level of c-myc was the highest in Ad- XC infected cells. Tumor formation was found at the injected site of mice inoculated with Ad-XC-infected LO2 cells, but not in control mice.CONCLUSION： Ad-XC, Ad-X and Ad-C facilitate the proliferation activity of HepG2 cells and inhibit their apoptosis in vitro. The effect of Ad-XC is significantly stronger than that of Ad-X and Ad-C. Up-regulation of c-myc may be one of the mechanisms underlying the synergism of HBVX and HCV C genes on hepatocarcinogenesis in athymic nude mice.

关键词： Hepatitis B virus X gene Hepatitis C virus core gene Hepatocellular carcinoma Proliferation Apoptosis