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Asymmetrical Diffusion-Induced Directional Motion

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Communications in Theoretical Physics 2004年第5X期42卷 707-710页

作者： baojing-dong WANGHai-Yan SONGYan-Li TheKeyLaboratoryofBeamTechniqueandMaterialModificationoftheMinistryofEducation BeijingNormalUniversityBeijing100875China DepartmentofPhysics BeijingNormalUniversityBeijing100875China

Competition between anomalous diffusion and normal diffusion along two different directions of the track for a Brownian motor, combined with a periodic potential flashing, can lead to a macroscopic motion. The current is calculated analytically by using the Astumian-Bier's approach of the step number per cycle. It is shown that the direction of current occurs reversal for different waiting times of the potential off and the magnitude of current is prominently enhanced. Moreover, a thermal "green" noise is proposed to produce the ballistic diffusion, numerical simulations for the average velocity of the particle in the presence of ballistic and normal diffusions support the present theoretical findings.

关键词：不平衡波动不对称结构对称分布时间周期偏微分方程

Average Cycle Period in Asymmetrical Flashing Ratchet

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Communications in Theoretical Physics 2005年第2期43卷 229-232页

作者： WANGHai-Yan HEHou-Sheng baojing-dong DepartmentofPhysics BeijingNormalUniversityBeijing100875China DepartmentofPhysics BeijingNormalUniversityBeijing100875China／／TheKeyLaboratoryofBeamTechniqueandMaterialModificationofMinistryofEducationBeijingNormalUniversityBeijing100875China

The directed motion of a Brownian particle in a Bashing potential with various transition probabilities and waiting times in one of two states is studied. An expression for the average cycle period is proposed and the steady current J of the particle is calculated via Langevin simulation. The results show that the optimal cycle period (Tm), which takes the maximum of J, is shifted to a small value when the transition probability A from the potential on to the potential off decreases, the maximal current appears in the case of the average waiting time in the potential on being longer than in the potential off, and the direction of current depends on the ratio of the average times waiting in two states.

关键词： Brownian motor current asymmetrical transition

Asymmetry of Coordinate and Velocity in Noisy Oscillator

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Communications in Theoretical Physics 2005年第1期43卷 97-101页

作者： SONGYan-Li baojing-dong WANGHai-Yan JIQing DepartmentofPhysics BeijingNormalUniversityBeijing100875China DepartmentofPhysics BeijingNormalUniversityBeijing100875China／／TheKeyLaboratoryofBeamTechniqueandMaterialModificationofMinistryofEducationBeijingNormalUniversityBeijing100875China DepartmentofPhysics HebeiUniversityofTechnologyTianjin300130China

The velocity variable of a noise oscillator as an internal or external noise is proposed, the spectrum of which is quite different from that of the coordinate variable of the same noise oscillator. The former leads to ballistic diffusion for a free particle in long time limit and the asymptotical results of the system are sensitive to the initial condition. However, diffusion process induced by the coordinate of noise oscillator is a normal one and depends on the initial condition only in the transient time. This allows us to classify two kinds of non-Markovian processes: normal one and strong one, just like the processes induced by the coordinate and the velocity of noise oscillator, *** to a correlation ratchet, we have found that the steady current of a particle subjected to the velocity of noise oscillator is opposite to that subjected to its coordinate, thus the former shows greenness and the latter redness.

关键词： velocity noise coordinate noise ballistic diffusion non-Markovian Langevinequation correlation ratchet

心脏超声诊断高血压左室肥厚伴左心力衰竭的临床研究

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中国医药指南 2021年第1期19卷 50-51页

作者：董宝镜朝阳市中心医院心脏血管超声科辽宁朝阳122000

目的研究心脏超声诊断高血压左室肥厚伴左心力衰竭的临床价值。方法选择2018年3月至2019年3月我院收治的40例高血压左室肥厚伴左心力衰竭患者为观察组,同时期内在我院进行常规检查的健康体检者40例为对照组,对两组研究对象均实施心脏彩... 详细信息

目的研究心脏超声诊断高血压左室肥厚伴左心力衰竭的临床价值。方法选择2018年3月至2019年3月我院收治的40例高血压左室肥厚伴左心力衰竭患者为观察组,同时期内在我院进行常规检查的健康体检者40例为对照组,对两组研究对象均实施心脏彩超,对比两组研究对象的各项指标数据。结果观察组在左室舒张末期内径、左室收缩末期内径、左室射血分数、舒张早期峰值流速(A峰值)、舒张晚期峰值流速(E峰值)和舒张早期峰值流速、舒张晚期峰值流速两项比值(E/A)等指标数据方面,与对照组之间的差异,具有统计学意义(P<0.05)。同时,观察组Ⅰ级患者、Ⅱ级患者和Ⅲ级患者在各项指标之间的差异,具有统计学意义(P<0.05)。结论对高血压左室肥厚伴左心力衰竭患者运用心脏彩超诊断,可有效鉴别患者的心力衰竭水平,为疾病治疗提供有力依据。

关键词：高血压左室肥厚伴左心力衰竭心脏超声

血管超声检查在预防2型糖尿病患者下肢坏疽中的意义

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中国医药指南 2021年第4期19卷 27-28页

作者：董宝镜朝阳市中心医院心脏血管超声科辽宁朝阳122000

目的探讨和研究血管超声检查在预防2型糖尿病患者下肢坏疽中的意义。方法选择102例2型糖尿病患者下肢坏疽患者为研究样本,随机将所有患者分为对照组和观察组,每组各51例。对照组患者采取常规基础性检查,对观察组患者实施血管超声检查。... 详细信息

目的探讨和研究血管超声检查在预防2型糖尿病患者下肢坏疽中的意义。方法选择102例2型糖尿病患者下肢坏疽患者为研究样本,随机将所有患者分为对照组和观察组,每组各51例。对照组患者采取常规基础性检查,对观察组患者实施血管超声检查。对两组患者的股动脉、腘动脉和足背动脉的内径和收缩期峰值流速等指标进行比较,对比两组患者的2型糖尿病下肢病变的检出率,如血管狭窄、硬化斑块和血管硬化等。结果在股动脉、腘动脉和足背动脉的内径和收缩期峰值流速等指标数据方面,观察组的检出情况显著优于对照组(P<0.05)。同时,对照组的检出率为66.66%,显著低于观察组的96.08%(P<0.05)。结论对2型糖尿病下肢坏疽患者进行彩色多普勒血管超声检查,可有效观察患者的各项指标数据,为疾病预防、诊断和治疗均能提供有效的参考依据,在临床中推广使用的可行性较大。

关键词：血管超声检查 2型糖尿病下肢坏疽意义

Resonance mechanism of flapping wing based on fluid structure interaction simulation

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Chinese Journal of Aeronautics 2024年第5期37卷 243-262页

作者： Yueyang GUO Wenqing YANG Yuanbo dong dong XUE National Key Laboratory of Science and Technology on Aerodynamic Design and Research School of AeronauticsNorthwestern Polytechnical UniversityXi'an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063China Yangtze River Delta Research Institute of Northwestern Polytechnical University Taicang 215400China

Certain insect species have been observed to exploit the resonance mechanism of their *** order to achieve resonance and optimize aerodynamic performance,the conventional approach is to set the flapping frequency of flexible wings based on the Traditional Structural Modal(TSM)***,there exists controversy among researchers regarding the relationship between frequency and aerodynamic *** that the structural response of wings can be influenced by the surrounding air vibrations,an analysis known as Acoustic Structure Interaction Modal(ASIM)is introduced to calculate the resonant *** this study,Fluid Structure Interaction(FSI)simulations are employed to investigate the aerodynamic performance of flapping wings at modal frequencies derived from both TSM and ASIM *** performance is evaluated for various mass ratios and frequency ratios,and the findings indicate that the deformation and changes in vortex structure exhibit similarities at mass ratios that yield the highest aerodynamic ***,the flapping frequency associated with the maximum time-averaged vertical force coefficient at each mass ratio closely aligns with the ASIM frequency,as does the frequency corresponding to maximum ***,the ASIM analysis can provide an effective means for predicting the optimal flapping frequency for flexible ***,it enables the prediction that flexible wings with varying mass ratios will exhibit similar deformation and vortex structure *** paper offers a fresh perspective on the ongoing debate concerning the resonance mechanism of Flexible Flapping Wings(FFWs)and proposes an effective methodology for predicting their aerodynamic performance.

关键词： Flexible Flapping Wing(FFW) Acoustic Structure Interaction Modal(ASIM) Fluid Structure Interaction(FSI) Resonance mechanism Aerodynamic performance

Copper slag assisted coke reduction of phosphogypsum for sulphur dioxide preparation

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Chinese Journal of Chemical Engineering 2024年第1期65卷 43-53页

作者： dong Ma Qinhui Wang State Key Laboratory of Clean Energy Utilization Institute for Thermal Power EngineeringZhejiang UniversityHangzhou 310027China

The reduction of phosphogypsum(PG)to lime slag and SO_(2)using coke can effectively alleviate the environmental problems caused by ***,the PG decomposition temperature remains high and the product yield remains *** adding additives,the decomposition temperature can be further reduced and PG decomposition rate and product yield can be ***,the use of current additives such as Fe_(2)O_(3)and SiO_(2)brings the problem of increasing economic ***,it is proposed to use solid waste copper slag(CS)as a new additive to reduce PG to prepare SO2,which can reduce the cost and meet the environmental benefits at the same *** effects of proportion,temperature and thermostatic time on PG decomposition are investigated by experimental and kinetic analysis combined with FactSage thermodynamic calculations to optimize the roasting ***,the reaction mechanism is *** is found that adding CS to the coke and PG system can increase the rate of PG decomposition and SO_(2)yield while lowering the PG decomposition *** example,when the CS/PG mass ratio increases from 0 to 1,PG decomposition rate increases from 83.38%to 99.35%,SO_(2)yield increases from 78.62%to 96.81%,and PG decomposition temperature decreases from 992.4℃to 949.6℃.The optimal reaction parameters are CS/PG mass ratio of 1,Coke/PG mass ratio of 0.06 at 1100℃for 20 min with 99.35%PG decomposition rate and 96.81%SO_(2) *** process proceeds according to the following reactions:2CaSO_(4)+ 0.7C + 0.8Fe_(2)SiO_(4)→0.8Ca_(2)SiO_(4)+ 0.2Ca_(2)Fe_(2)O_(5)+ 0.4Fe_(3)O_(4)+2SO_(2)+ 0.7CO_(2)Finally,a process for decomposing PG with coke and CS is proposed.

关键词： Phosphogypsum Sulfur dioxide Copper slag Fluidized-bed Reduction Waste treatment

Finite-time Prescribed Performance Time-Varying Formation Control for Second-Order Multi-Agent Systems With Non-Strict Feedback Based on a Neural Network Observer

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1039-1050页

作者： Chi Ma Dianbiao dong the School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China

This paper studies the problem of time-varying formation control with finite-time prescribed performance for nonstrict feedback second-order multi-agent systems with unmeasured states and unknown *** eliminate nonlinearities,neural networks are applied to approximate the inherent dynamics of the *** addition,due to the limitations of the actual working conditions,each follower agent can only obtain the locally measurable partial state information of the leader *** address this problem,a neural network state observer based on the leader state information is ***,a finite-time prescribed performance adaptive output feedback control strategy is proposed by restricting the sliding mode surface to a prescribed region,which ensures that the closed-loop system has practical finite-time stability and that formation errors of the multi-agent systems converge to the prescribed performance bound in finite ***,a numerical simulation is provided to demonstrate the practicality and effectiveness of the developed algorithm.

关键词： Finite-time control multi-agent systems neural network prescribed performance control time-varying formation control

Resilient control of flexible hypersonic vehicles against unmatched distributed faults

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Chinese Journal of Aeronautics 2024年第5期37卷 60-70页

作者： dong ZHAO Wenjing REN School of Artificial Intelligence Anhui UniversityHefei 230601China Key Laboratory of System Control and Information Processing Ministry of EducationShanghai Jiao Tong UniversityShanghai 200240China School of Electrical Engineering and Automation Hefei University of TechnologyHefei 230009China

This paper studies a robust fault compensation and vibration suppression problem of flexible hypersonic *** controlled plant is represented by a cascade system composed of a nonlinear Ordinary Differential Equation(ODE)and an Euler-Bernoulli Beam Equation(EBBE),in which the vibration dynamics is coupled with the rigid dynamics and suffers from distributed faults.A state differential transformation is introduced to transfer distributed faults to an EBBE boundary and a longitudinal dynamics is refined by utilizing T-S fuzzy IF-THEN rules.A novel T-S fuzzy based fault-tolerant control algorithm is developed and related stability conditions are *** robust exponential stability and well-posedness are proved by using the modified l_(0)-semigroup based Lyapunov direct approach.A simulation study on the longitudinal dynamics of flexible hypersonic vehicles effectively verifies the validity of the developed theoretical results.

关键词： Flexible hypersonic vehicles ODE-EBBE cascade Robust exponential stability Unmatched distributed fault compensation Vibration suppression