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181.
The design and artificial realization of a controller of pulse coupling feedback 总被引:1,自引:0,他引:1 下载免费PDF全文
In this paper a controller of pulse coupling feedback (PCF) is designed to control chaotic
systems. Control principles and the technique to select the feedback
coefficients are introduced. This controller is theoretically studied with a
three dimensional (3D) chaotic system. The artificial simulation results
show that the chaotic system can be stabilized to different periodic orbits
by using the PCF method, and the number of the periodic orbits are
2n× 3mp (n and m are integers). Therefore, this control method is
effective and practical. 相似文献
182.
等效电流偶极子(ECD)模型具有简要明确性,已经在心磁图(MCG)的逆问题中,如确定WPW综合症、心脏异常搏动根源、心律失常等方面,得到广泛应用.在多通道体表电势图(BSPM)的测量中也应用ECD.本文讨论用ECD的定位方法,临床研究仿真对ECD获得结果的描述,造影与动物研究和体导体模型的影响. 相似文献
183.
The zero-asymptotic property of sliding variables in discrete systems is extended to a continuous one and applied to partial
differential equations which describe spatiotemporal chaos. A method of chaos synchronization and parameter identification
is proposed. The synchronization controllers and the parameter recognizers are designed. The uncertain Gray-Scott system is
taken as an example to verify the effectiveness of the method. Simulation results show that the identification variables in
the parameter recognizers may take the place of the unknown parameters in both target and response systems. Global synchronization
of the two spatiotemporal chaotic systems with uncertain parameters may be realized quickly after controllers are added.
Supported by the Natural Science Foundation of Liaoning Province, China (Grant No. 20052151) and the Innovative Team Program
of Liaoning Educational Committee 相似文献
184.
Ling Wu Xiaohua Yang Yangqin Chen 《Journal of Quantitative Spectroscopy & Radiative Transfer》2008,109(9):1586-1589
Thirty-four rovibronic spectral lines of the Ω=1/2 component of the (4, 8) band in the A-X system of 35Cl2+ were observed in the range of 16,940-17,010 cm−1, employing optical heterodyne-enhanced velocity modulation spectroscopy. Nonlinear least-squares fitting the effective Hamiltonians results in precise band origin and other molecular constants of the levels involved. 相似文献
185.
Area postrema (AP) is a circumventricular organ plays an important role in sodium homeostasis and cardiovascular regulation. Since sleep deficiency will cause cardiovascular dysfunction, the present study aims to determine whether sodium level would significantly alter in AP following total sleep deprivation (TSD). Sodium level was investigated in vivo by time-of-flight secondary ion mass spectrometry (TOF-SIMS). Clinical manifestation of cardiovascular function was demonstrated by mean arterial pressure (MAP) values. Results indicated that in normal rats, TOF-SIMS spectrum revealed a major peak of sodium ion counting as 5.61 × 105 at m/z 23. The sodium ions were homogeneous distributed in AP without specific localization. However, following TSD, the sodium intensity was relatively increased (6.73 × 105) and the signal for sodium image was strongly expressed throughout AP with definite spatial distribution. MAP of TSD rats is 138 ± 5 mmHg, which is significantly higher than that of normal ones (121 ± 3 mmHg). Regarding AP is an important area for sodium sensation and development of hypernatremic related sympatho-excitation; up-regulation of sodium expression following TSD suggests that high sodium level might over-activate AP, through complex neuronal networks involving in sympathetic regulation, which could lead to the formation of TSD relevant cardiovascular diseases. 相似文献
186.
187.
Hui Ling Chia Naziah Mohamad Latiff Dr. Rui Gusmão Prof. Zdeněk Sofer Prof. Martin Pumera 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(9):2242-2249
The experimental achievement of phosphorene, which exhibits superior electronic, physical, and optical properties has spurred recent interest in other Group 15 elemental 2D nanomaterials such as arsenene, antimonene, and bismuthene. These unique and superior properties of the pnictogen nanosheets have spurred intensive research efforts and led to the discovery of their diversified potential applications; for instance, optical Kerr material, photonic devices, pnictogen-decorated microfibers, high-speed transistors, and flexible 2D electronics. Previous studies have mainly been dedicated to study the synthesis, properties, and applications of the heavy pnictogens nanosheets; however, the toxicological behaviour of these nanosheets has yet to be established. Herein, the cytotoxicity study of pnictogen nanosheets (As, Sb, and Bi) was conducted over 24 h of incubation with various concentrations of test materials and adenocarcinoma human lung epithelial A549 cells. After the treatment period, the remaining cell viabilities were obtained through absorbance measurements with WST-8 and MTT assays. These findings demonstrate that the toxicity of pnictogen nanosheets decreases down Group 15, whereby arsenic nanosheets are considered to be the most toxic, whereas bismuth nanosheets induce low cytotoxicity. The findings of this study constitute an important initial step towards enhancing our understanding of the toxicological effects of pnictogen nanosheets in light of their prospective commercial applications. 相似文献
188.
Yushu Liu Chun Gao Qing Li Prof. Dr. Huan Pang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(9):2141-2160
Nickel oxide (NiO) has emerged as one of the most promising transition-metal oxides (TMOs) for electrochemical capacitors, batteries, catalysis, and electrochromic films, owing to its cost-effectiveness, abundance, and well-defined electrochemical properties. Recent studies have identified that mixing NiO with graphene or graphene derivatives results in novel composites with synergistic effects and superior electrochemical performance. This review summarizes the latest advances in composites of NiO with graphene or graphene derivatives. The synthetic strategies, morphologies, and electrochemical performance of these composites are introduced, as well as their electrochemical applications in supercapacitors, batteries, sensors, catalysis, and so forth. Finally, tentative conclusions and assessments regarding the opportunities and challenges for the future development of these composites and other TMOs/graphene or graphene-derived composites are presented. 相似文献
189.
190.
In the conventional scheme of generating strong mechanical squeezing by the joint effect between mechanical parametric amplification and sideband cooling, the resolved sideband condition is required so as to overcome the quantum backaction heating. In the unresolved sideband regime, to suppress the quantum backaction, a χ(2) nonlinear medium is introduced to the cavity. The result shows that the quantum backaction heating effect caused by unwanted counter-rotating term can be completely removed. Hence, the strong mechanical squeezing can be obtained even for the system far from the resolved-sideband regime. 相似文献