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More Divisibility Properties for Binomial Coefficients

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Journal of Mathematical Research with Applications 2022年第6期42卷 561-579页

作者： Jiaqi xiao Yuqing he Pingzhi yuan School of Mathematics South China Normal University

Let a, b and n be positive integers with a > b, we prove the following divisibility property: For all positive integers n, we have ■which extends the result of Yang. And for all positive integers n, we show the follo... 详细信息

关键词： binomial coefficients p-adic order divisibility property

Nonlinearity analysis of piezoelectric micromachined ultrasonic transducers based on couple stress theory

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Acta Mechanica Sinica 2012年第1期28卷 104-111页

作者： Xin Kang Fu-Jun Yang Xiao-yuan He Department of Applied Mechanics Nanjing University of Science and Technology210094 NanjingChina Department of Mechanical and Aeronautical Engineering University of CaliforniaDavis95616US Institute of Engineering Mechanics Southeast University210096 NanjingChina

This paper studies the static deformation behavior of a piezoelectric micromachined ultrasonic transducer （PMUT） actuated by a strong external electric field. The transducer membrane consists of a piezoelectric layer, a passive layer and two electrode layers. The nonlinearities of the piezoelectric layer caused by electrostriction under a strong electric field are analyzed. Because the thickness of the transducer membrane is on the microscale, the size dependence of the deformation behavior is evaluated using the couple stress theory. The results show that the optimal ratio of the top electrode diameter and the membrane diameter is around 0.674. It is also found that this optimal value does not depend on any other parameters if the thicknesses of the two electrodes are negligible compared with those of the piezo- electric and passive layers. In addition, the nonlinearities of the piezoelectric layer will become stronger along with the increase of the electric field, which means that softening of the membrane stiffness occurs when a strong external electric field is applied. Meanwhile, the optimal thickness ratio for the passive layer and the piezoelectric layer is not equal to 1.0 which is usually adopted by previous researchers. Because there exists size dependence of membrane deforma-tion, the optimal value of this thickness ratio needs to be greater than 1.0 on the microscale.

关键词： Piezoelectric micromachined ultrasonic trans- ducer （PMUT） Couple stress theory Static deformation - Nonlinearity analysis

Efficacy and safety of different anti-osteoporotic drugs for the spinal fusion surgery: A network meta-analysis

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World Journal of Clinical Cases 2023年第30期11卷 7350-7362页

作者： Xiao-yuan He Huan-Xiong Chen Zhi-Rong Zhao Spinal Surgery Hainan Province Clinical Medical CenterHaikou 570100Hainan ProvinceChina

BACKGROUND Administering anti-osteoporotic agents to patients perioperatively is a widely accepted approach for improving bone fusion rates and reducing the risk of complications.The best anti-osteoporotic agents for spinal fusion surgery remain unclear.AIM To investigate the efficacy and safety of different anti-osteoporotic agents in spinal fusion surgery via network meta-analysis.METHODS Searches were conducted in four electronic databases(PubMed,EMBASE),Web of Science,the Cochrane Library and China National Knowledge Infrastructure(CNKI)from inception to November 2022.Any studies that compared antiosteoporotic agents vs placebo for spinal fusion surgery were included in this network meta-analysis.Outcomes included fusion rate,Oswestry disability index(ODI),and adverse events.Network meta-analysis was performed by R software with the gemtc package.RESULTS In total,13 randomized controlled trials were included in this network metaanalysis.Only teriparatide(OR 3.2,95%CI:1.4 to 7.8)was more effective than placebo in increasing the fusion rate.The surface under the cumulative ranking curve(SUCRA)of teriparatide combined with denosumab was the highest(SUCRA,90.9%),followed by teriparatide(SUCRA,74.0%),zoledronic acid(SUCRA,43.7%),alendronate(SUCRA,41.1%)and risedronate(SUCRA,35.0%).Teriparatide(MD-15,95%CI:-28 to-2.7)and teriparatide combined with denosumab(MD-20,95%CI:-40 to-0.43)were more effective than placebo in decreasing the ODI.The SUCRA of teriparatide combined with denosumab was highest(SUCRA,90.8%),followed by teriparatide(SUCRA,74.5%),alendronate(SURCA,52.7),risedronate(SURCA,52.1%),zoledronic acid(SURCA,24.2%)and placebo(SURCA,5.6%)for ODI.The adverse events were not different between groups.CONCLUSION This network meta-analysis suggests that teriparatide combined with denosumab and teriparatide alone significantly increase the fusion rate and decrease the ODI without increasing adverse events.Based on current evidence,teriparatide combined with denosumab or teriparatide alone is recommended to increase

关键词： Anti-osteoporotic agents Spinal fusion procedure Network meta-analysis Systematic review Denosumab

Degree dependence entropy descriptor for complex networks

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Advances in Manufacturing 2013年第3期1卷 284-287页

作者： Xiang-Li Xu xiao-Feng Hu Xiao-yuan He Department of Information Operation and Command Training NDU of PLA No.65047 Troops of PLA

In order to supply better accordance for mod eling and simulation of complex networks, a new degree dependence entropy （DDE） descriptor is proposed to describe the degree dependence relationship and corre sponding characteristic in this paper. First of all, degrees of vertices and the shortest path lengths between all pairs of ,ertices are computed. Then the degree dependence matrices under different shortest path lengths are con structed. At last the DDEs are extracted from the degree dependence matrices. Simulation results show that the DDE descriptor can reflect the complexity of degree dependence relationship in complex networks; high DDE indicates complex degree dependence relationship; low DDE indicates the opposite one. The DDE can be seen as a quantitative statistical characteristic, which is meaningful for networked modeling and simulation.

关键词： Degree dependence matrix Degreedependence entropy （DDE） - Entropy Complex networks

Hybrid model for muon tomography and quantitative analysis of image quality

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Nuclear Science and Techniques 2022年第7期33卷 1-13页

作者： Si-yuan Luo Yu-he Huang Xuan-Tao Ji Lie he Wan-Cheng xiao Feng-Jiao Luo Song Feng Min xiao xiao-Dong Wang School of Nuclear Science and Technology University of South ChinaHengyang 421001China

Muon tomography is a novel method for the non-destructive imaging of materials based on muon rays,which are highly penetrating in natural background radiation.Currently,the most commonly used imaging methods include muon radiography and muon tomography.A previously studied method known as coinciding muon trajectory density tomography,which utilizes muonic secondary particles,is proposed to image low and medium atomic number(Z)materials.However,scattering tomography is mostly used to image high-Z materials,and coinciding muon trajectory density tomography exhibits a hollow phenomenon in the imaging results owing to the self-absorption effect.To address the shortcomings of the individual imaging methods,hybrid model tomography combining scattering tomography and coinciding muon trajectory density tomography is proposed and verified.In addition,the peak signal-to-noise ratio was introduced to quantitatively analyze the image quality.Different imaging models were simulated using the Geant4 toolkit to confirm the advantages of this innovative method.The simulation results showed that hybrid model tomography can image centimeter-scale materials with low,medium,and high Z simultaneously.For high-Z materials with similar atomic numbers,this method can clearly distinguish those with apparent differences in density.According to the peak signal-to-noise ratio of the analysis,the reconstructed image quality of the new method was significantly higher than that of the individual imaging methods.This study provides a reliable approach to the compatibility of scattering tomography and coinciding muon trajectory density tomography.

关键词： Monte Carlo simulation Muon tomography Image reconstruction

Improvement of Electronic Line-shafting Control in Multi-axis Systems

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International Journal of Automation and computing 2018年第4期15卷 474-481页

作者： Chang-Fan Zhang yuan-yuan xiao Jing he Min Yan College of Electrical and Information Engineering Hunan University of Technology College of Mechatronic Engineering and Automation National University of Defense Technology

Electronic line-shafting （ELS） is the most popular control strategy for printing machines with shaftless drives. A sliding-mode controller for tracking control is designed in this study as the first step towards an improved ELS control scheme. This controller can eliminate the negative effects on synchronization precision resulting from the friction at low speed present in the pre-registration step of a shaftless driven printing machine. Moreover, it can eliminate the synchronization error of the printing process resulting from nonlinearities and load disturbances. Based on observer techniques, the unknown components of load torque and system parameter variations are estimated. On this basis, a novel ELS control method using equivalent load-torque observers is proposed. Experimental results demonstrate the effectiveness of the proposed control system for four-axis position control.

关键词： Shaftless drive sliding-mode controller nonlinearity observer synchronization position control multi-axis system

Effect of switching from treatment with nucleos(t)ide analogs to pegylated interferon α-2a on virological and serological responses in chronic hepatitis B patients

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World Journal of Gastroenterology 2016年第46期22卷 10210-10218页

作者： Li-Ting he xiao-Guang Ye xiao-yuan Zho Department of Infectious Diseases The Second Affiliated Hospital of Guangzhou Medical University

AIM To investigate the efficacy of switching to pegylated interferon-α-2a(Peg IFNα-2a) treatment in nucleos(t)ide analog(NA)-treated chronic hepatitis B(CHB) responder patients. METHODS A 48-wk prospective and retrospective treatment trial of NA-treated CHB patients who had received entecavir(ETV) for at least 48 wk and had serum hepatitis B virus(HBV)-DNA hepatitis B envelope antigen(HBe Ag) he upper limit of normal of 40 IU/L was performed. The effects on virological and serological responses and adverse reactions to 0.5 mg daily ETV for 48 wk vs switching to Peg IFNα-2a were compared. Forty-four patients were randomized to be switched from NA treatment to the Peg IFNα-2a group, and 44 patients were simultaneously randomized to the ETV group. RESULTS After 48 wk of therapy, the decrease in hepatitis B surface antigen(HBs Ag) levels was greater in the Peg IFNα-2a group than in the ETV group(3.1340 log10 IU/m L vs 3.6950 log10 IU/m L, P = 0.00). Seven patients who were anti-HBs-positive at baseline achieved HBs Ag loss when switched to Peg IFNα-2a(15.91% vs 0%,P = 0.018). The HBe Ag serological conversion rate was higher in the Peg IFNα-2a group than in the ETV group; however, the difference was not significant because of the small sample sizes(34.38% vs 21.88%, P = 0.232). In the Peg IFNα-2a group, patients with HBs Ag levels her HBe Ag seroconversion and HBs Ag loss rates at week 48 than those with HBs Ag levels ≥ 1500 IU/m L(HBe Ag seroconversion: 17.86% vs 62.5%, P = 0.007; HBs Ag loss: 41.67% vs 6.25%, P = 0.016). Moreover, patients with HBs Ag levels her HBs Ag loss rates after therapy than those with HBs Ag levels ≥ 1500 IU/m L(36.84% vs 0%, P = 0.004). However, there were no statistically significant differences in HBe Ag seroconversion rates(47.06% vs 25.93%, P = 0.266). CONCLUSION NA-treated CHB patients switched to sequential Peg I

关键词：长期的肝炎 B Entecavir pegylated interferon-α -2a 顺序的治疗效果

Arbitrary-Order Fractance Approximation Circuits With High Order-Stability Characteristic and Wider Approximation Frequency Bandwidth

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IEEE/CAA Journal of Automatica Sinica 2020年第5期7卷 1425-1436页

作者： Qiu-Yan he Yi-Fei Pu Bo Yu xiao yuan College of Computer Science Sichuan UniversityChengdu 610065China College of Physics and Engineering Chengdu Normal UniversityChengdu 611130China College of Electronics and Information Engineering Sichuan UniversityChengdu 610065China

This paper discusses a novel rational approximation algorithm of arbitrary-order fractances,which has high orderstability characteristic and wider approximation frequency bandwidth.The fractor has been exploited extensively in various scientific domains.The well-known shortcoming of the existing fractance approximation circuits,such as the oscillation phenomena,is still in great need of special research attention.Motivated by this need,a novel algorithm with high orderstability characteristic and wider approximation frequency bandwidth is introduced.In order to better understand the iterating process,the approximation principle of this algorithm is investigated at first.Next,features of the iterating function and frequency-domain characteristics of the impedance function calculated by this algorithm are researched,respectively.Furthermore,approximation performance comparisons have been made between the corresponding circuit and other types of fractance approximation circuits.Finally,a fractance approximation circuit with the impedance function of negative2/3-order is designed.The high order-stability characteristic and wider approximation frequency bandwidth are fundamental important advantages,which make our proposed algorithm competitive in practical applications.

关键词： Fractal fractance fractional calculus fractional-order systems

Reference device for calibration of radon exhalation rate measuring instruments and its performance

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Nuclear Science and Techniques 2023年第8期34卷 131-141页

作者： Wei-Gang Li De-Tao xiao Zheng-Zhong he Xiang-yuan Deng Shou-Kang Qiu School of Nuclear Science and Technology Hunan Provincial Key Laboratory of RadonUniversity of South ChinaHengyang 421001China

Environmental radon emanates from the exhalation and release of soil,rocks,and building materials.Environmental radon contamination tracing and radon pollution prevention and control require the measurement of the radon exhalation rate on media surfaces.Reliable measurements of the radon exhalation rate cannot be achieved without regular calibration of the measuring instrument with a high-performance reference device.In this study,a reference device for the calibration of radon exhalation rate measuring instruments was developed using a diffusion solid radon source with a high and stable radon emanation coefficient,an integrated diffusion component composed of a plasterboard and a high-density wooden board,an air pressure balance device,a radon accumulation chamber,and a support structure.The uniformity and stability of the reference device were evaluated using the activated carbon-γspectrum and open-loop method,respectively,to measure the radon exhalation rate.The reference device achieved different radon exhalation rates by using different activities of diffusion solid radon sources.Nineteen measurement points were regularly selected on the radon exhalation surface of the reference device,and the uniformity of the radon exhalation rate exceeded 5%.The short-term stability of the reference device was better than 5%under different environmental conditions and was almost unaffected by the ambient air pressure,environmental temperature,and relative humidity.

关键词： Radon exhalation rate Stability Uniformity High-density wooden board Plasterboard