检索结果-南通市图书馆

Suppression of Chaotic Behaviors in a Complex Biological System by Disturbance Observer-based Derivative-Integral Terminal Sliding Mode

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2020年第1期7卷 126-135页

作者： Dianwei Qian hui ding SukGyu Lee Hyansu Bae School of Control and Computer Engineering North China Electric Power UnverisityBeijing 102206China Department of Anesthesia Shaanxi Provincial People’s HospitalXi’anChina Department of Electrical Engineering Yeungnam UniversityGyeongsanRepublic of Korea

Coronary artery systems are a kind of complex biological systems. Their chaotic phenomena can lead to serious health problems and illness development. From the perspective of engineering, this paper investigates the chaos suppression problem. At first, nonlinear dynamics of coronary artery systems are presented. To suppress the chaotic phenomena, the method of derivative-integral terminal sliding mode control is adopted. Since coronary artery systems suffer from uncertainties, the technique of disturbance observer is taken into consideration. The stability of such a control system that integrates the derivative-integral terminal sliding mode controller and the disturbance observer is proven in the sense of Lyapunov. To verify the feasibility and effectiveness of the proposed strategy, simulation results are illustrated in comparison with a benchmark.

关键词： Biological systems chaos suppression coronary artery nonlinear dynamics sliding mode control(SMC)

A Reliability Analysis of Calculated Results for Odd-Even and Odd-Odd Nuclei in Relativistic Mean-Field Theory

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2006年第1X期46卷 113-118页

作者： ding Bin-Gang ZHANG Da-Li LU ding-hui School of Science Huzhou Teachers College Huzhou 313000 China Institute of Modern Physics Zhejiang University Hangzhou 310027 China

We calculate the binding energies of Ni, Cu, Xe, Cs, Pt, Au, Np, Pu isotope chains using two interaction parameter sets NL-3 and NL-Z, and compared the relative errors of the even-even nuclei with those of odd-even nuclei and odd-odd nuclei. We find that the errors of binding energy of odd-even and odd-odd nuclei are not bigger than the one of even-even nuclei. The result shows that comparing with even-even nuclei, there is no systematic error and approximation in the calculations of the binding energy of odd-even and odd-odd nuclei with relativistic mean-field theory. In addition, the result is explained theoretically.

关键词： relativistic mean-field theory binding energy even-even nuclei odd-even nuclei odd-odd nuclei

Computing Ground State Solution of Bose-Einstein Condensates Trapped in One-Dimensional Harmonic Potential

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2006年第5X期46卷 873-878页

作者： YUAN Qing-Xin ding Guo-hui Department of Mathematics and Physics Zhengzhou Institute of Aeronautical Industry Management Zhengzhou 450015 China Department of Physics Shanghai Jiao Tong University Shanghai 200030 China

For Bose-Einstein condensates trapped in a harmonic potential well, we present numerical results from solving the tlme-dependent nonlinear Schrolinger equation based on the Crank-Nicolson method. With this method we are able to find the ground state wave function and energy by evolving the trial initial wave function in real and imaginary time spaces, respectively. In real time space, the results are in agreement with [Phys. Rev. A 51 （1995） 4704], but the trial wave function is restricted in a very small range. On the contrary, in imaginary time space, the trial wave function can be chosen widely, moreover, the results are stable.

关键词： Bose-Einstein condensates nonlinear Schrodinger equation Crank-Nicolson method

Optimization of microwave-assisted extraction of wedelolactone from Eclipta alba using response surface methodology

在线全文

学校读者我要写书评

暂无评论

Frontiers of Chemical Science and Engineering 2014年第1期8卷 34-42页

作者： Dajing SHI hui ding Shimin XU School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China National Engineering Research Center of Distillation Technology Tianjin 300072 China School of Environmental Science and Engineering Tianjin University Tianjin 300072 China

An efficient microwave-assisted extraction tech- nique was used to extract wedelolactone from Eclipta alba. To optimize the effects of the microwave-assisted extraction （MAE） processing parameters on the yield ofwedelolactone, a response surface methodology with a central composite rotatable design was employed. Four independent variables were investigated： microwave power, ethanol concentration, extraction time and the solvent-to-solid ratio. The optimum conditions were： microwave power, 208 W; ethanol con- centration, 90%; extraction time, 26.5 min; and solvent-to- solid ratio, 33 mL.g-~. Under the optimal conditions, the extraction yield of wedelolactone was （82.67±0.16）%, which is in close agreement with the value predicted by the statistical model. MAE was also compared to other conventional methods, including ultrasonic assisted extrac- tion, extraction at room temperature and heat reflux extraction. MAE has distinct advantages for the extraction of wedelolactone in terms of both time and efficiency. Therefore, MAE is a reliable method for the extraction of wedelolactone from Eclipta alba.

关键词： microwave-assisted extraction optimize,response surface methodology wedelolactone

On-Machine Measurement of the Straightness and Tilt Errors of a Linear Slideway Using a New Four-Sensor Method

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2019年第2期32卷 122-132页

作者： Lei Zhao Kai Cheng hui ding Liang Zhao School of Mechatronics Engineering Harbin Institute of Technology College of Engineering Design and Physical Sciences Brunel University

Although there are some multi-sensor methods for measuring the straightness and tilt errors of a linear slideway, they need to be further improved in some aspects, such as suppressing measurement noise and reducing *** this paper, a new four-sensor method with an improved measurement system is proposed to on-machine separate the straightness and tilt errors of a linear slideway from the sensor outputs, considering the influences of the reference surface profile and the zero-adjustment values. The improved system is achieved by adjusting a single sensor to di erent positions. Based on the system, a system of linear equations is built by fusing the sensor outputs to cancel out the e ects of the straightness and tilt errors. Three constraints are then derived and supplemented into the linear system to make the coe cient matrix full rank. To restrain the sensitivity of the solution of the linear system to the measurement noise in the sensor outputs, the Tikhonov regularization method is utilized. After the surface profile is obtained from the solution, the straightness and tilt errors are identified from the sensor outputs. To analyze the e ects of the measurement noise and the positioning errors of the sensor and the linear slideway, a series of computer simulations are carried out. An experiment is conducted for validation, showing good consistency. The new four-sensor method with the improved measurement system provides a new way to measure the straightness and tilt errors of a linear slideway, which can guarantee favorable propagations of the residuals induced by the noise and the positioning errors.

关键词： Multi-sensor method Straightness error Tilt error On-machine measurement Linear slideway Error separation technique

Distribution uniformity of added elements in twin-roll cast Al–Zn–Mg–Cu alloy by multi-electromagnetic fields

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2015年第8期34卷 546-552页

作者： Xin Su Guang-Ming Xu ding-hui Jiang School of Materials and Metallurgy Northeastern University Key Laboratory of Ministry of Education for Electromagnetic Processing of Materials Guangdong Donggong Information Science & Technology Company Limited

The micromorphology and the concentration o massive precipitates produced by twin-roll casting(TRC processes without and with multi-electromagnetic fields fo Al–Zn–Mg–Cu alloy at 670 °C were investigated in detai by means of optical microscopy(OM) and electron probe micro analyzer(EPMA). The results clearly show tha under a 0.2 T static magnetic field, the macro-segregation bands are remarkably alleviated according to the order o uniform static magnetic field, half-wave oscillating elec tromagnetic field as well as alternating oscillating elec tromagnetic field, as compared with the non-field TRC process(B = 0). Moreover, under the alternating oscillat ing electromagnetic TRC process, almost all segregation bands disappear. Additionally, through the observation on a smaller scale, the netlike precipitates elongated and broken by electromagnetic force, and replaced by numerous bulk depositions. EPMA analysis shows that the added atoms are diffused from deposition to a(Al) matrix, resulting in that the solute concentration in and around the precipitates is tending toward uniformity and stability.

关键词： Al–Zn–Mg–Cu alloy Electromagnetic field Twin-roll

Two new tetralone derivatives from the culture of Xylaria hypoxylon AT-028

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2008年第11期19卷 1323-1326页

作者： Wen Gu hui ding Department of Forestry Chemieal Engineering School of Chemical Engineering Nanjing Forestry University Nanjing 210037 China

Two new tetralone derivatives named xylariol A （1） and B （2） were isolated from the EtOAc extract of the culture broth of Xylaria hypoxylon AT-028 （Xylariaceae）, and their structures were elucidated by MS, 1R, 1D- and 2D-NMR spectra, and by X-ray diffraction analysis. 1 and 2 showed moderate cytotoxic activities against Hep G2 cells in the in vitro cytotoxic assay with IC50 values of 22.3 and 21.2 μg/mL, respectively.

关键词： Xylaria hvpoxylon Xylariol A Xylariol B Cylotoxicity

Numerical Study of φ^4 Model by Potential Importance Sampling Method

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2006年第5期45卷 873-876页

We investigate the phenomena of spontaneous symmetry breaking for φ^4 model on a square lattice in the parameter space by using the potential importance samplingmethod, which was proposed by Milchev, Heermann, and Binder [J. Star. Phys. 44 （1986） 749]. The critical values of the parameters allow us to determine the phase diagram of the model. At the same time, some relevant quantifies such as susceptibility and specific heat are also obtained.

关键词： symmetry breaking potential importance sampling method φ4 model

Temporal-spatial dynamic characteristics of vehicle emissions on intercity roads in Guangdong Province based on vehicle identity detection data

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2023年第8期130卷 126-138页

作者： hui ding Yongming Zhao Shenhua Miao Tong Chen Yonghong Liu College of Automation&College of Artifical Intelligence Nanjing University of Posts and TelecommunicationsNanjing 210023China School of Intelligent Systems Engineering Sun Yat-Sen UniversityGuangzhou 510275China Guangdong Provincial Key Laboratory of Intelligent Transport System Guangzhou 510275China Guangdong Provincial Engineering Research Center for Traffic Environmental Monitoring and Control Guangzhou 510275China

Estimating intercity vehicle emissions precisely would benefit collaborative control in multiple *** the variability of emissions caused by vehicles,roads,and traffic,the 24-hour change characteristics of air pollutants(CO,HC,NO_(X),PM_(2.5))on the intercity road network of Guangdong Province by vehicle categories and road links were revealed based on vehicle identity detection data in real-life traffic for each hour in July *** results showed that the spatial diversity of emissions caused by the unbalanced economywas *** vehicle emissions in the Pearl River Delta region(PRD)with a higher economic level were approximately 1–2 times those in the non-Pearl RiverDelta region(non-PRD).Provincial roads with high loads became potential sources of high ***,emission control policies must emphasize the PRD and key roads by travel guidance to achieve greater *** passenger cars with a large proportion of traffic dominated morning and evening peaks in the 24-hour period and were the dominant contributors to CO and HC emissions,contributing more than 50%in the daytime(7:00–23:00)and higher than 26%at night(0:00–6:00).Diesel trucks made up 10%of traffic,but were the dominant player at night,contributed 50%–90%to NO_(X) and PM_(2.5) emissions,with amarked 24-hour change rule of more than 80%at night(23:00–5:00)and less than 60%during ***,targeted control measures by time-section should be set up on collaborative *** findings provide time-varying decision support for variable vehicle emission control on a large scale.

关键词： Intercity roads Dynamic vehicle emissions Vehicle identity detection data Diesel trucks