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排序方式: 共有119条查询结果,搜索用时 15 毫秒
41.
研究了带有脉冲的时滞双向联想记忆(BAM)神经网络的稳定性问题.通过对网络系统的研究,根据脉冲的特点,采用Lyapunov稳定性理论和一些矩阵分析的技巧,得到了脉冲时滞BAM神经网络的稳定性结论,其中包括稳定点的唯一性判据和稳定性的判据,说明脉冲时滞BAM神经网络的稳定性问题是网络本身的特性,最后通过数值算例验证了论文的可行性和有效性. 相似文献
42.
Existence and exponential stability of almost periodic solutions for neutral‐type BAM neural networks with distributed leakage delays 下载免费PDF全文
Changjin Xu Peiluan Li Yicheng Pang 《Mathematical Methods in the Applied Sciences》2017,40(6):2177-2196
This paper is concerned with a class of neutral‐type BAM neural networks with distributed leakage delays. By applying the exponential dichotomy of linear differential equations, Lyapunov functional method and contraction mapping principle, we establish some sufficient conditions which ensure the existence and exponential stability of almost periodic solutions for such BAM neural networks. An example is given to illustrate the effectiveness of the theoretical findings. The results obtained in this article are completely new and complement the previously known studies. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
43.
《云南民族大学学报(自然科学版)》2015,(5):398-402
利用连续性原理及不等式技巧,对一类具中立型有界连续时滞的BAM神经网络模型概周期解的指数稳定性进行研究,得出了所研究模型的概周期解指数稳定的充分条件. 相似文献
44.
Gonçalves da Silva AM Romão RS Lucero Caro A Rodríguez Patino JM 《Journal of colloid and interface science》2004,270(2):417-425
The structural and dynamic characteristics of dioctadecyldimethylammonium bromide (DODAB) monolayers on a pure water subphase were investigated by surface film balance, Brewster angle microscopy, and relaxation in area and surface pressure at constant surface pressure and area, respectively. The first compression-expansion cycle of the monolayer is not reversible and the second pi-A compression isotherm deviates to larger molecular areas relative to the first one. At a microscopic level this hysteresis may be assigned to an irreversible hydration of the ammonium groups of DODAB. The morphology and reflectivity of DODAB monolayers during compression and expansion on the monolayer depend on the monolayer history. Bright domains randomly dispersed were observed during compression before collapse. Surprisingly, this random distribution of domains changes into a fractal-like structure during the monolayer expansion in a narrow range of surface pressures. This morphology does not form when the monolayer is previously compressed above the collapse surface pressure. 2D foam-like structure is often observed when the film is expanded at maximum area. Relaxation phenomena in DODAB monolayers are attributed to monolayer reorganization and nucleation of liquid-condensed domains from the liquid-expanded phase. These time-dependent processes are irreversible. 相似文献
45.
In situ photochromic process in the monolayer of aphotochromic spiropyran derivative without long alkyl chain,was investigated.The photochromism at the air/water interface under differnet surface pressures was studied by surface pressure-area isotherms,surface pressure-time curves,area-time curves and Brewster angle microscopy.Both forms of the compound were found to form monolayers at the air/water interface althouhg it does not have long alkyl chain.A large area expansion in the monolayer corresponding to a zreo^th order reaction was found at the initial stage of the UV light irradiation.A series of dynamic investigations revealed that at high pressure after phase transition in the monolayer,the surface pressure changes greatly umder alternative irradiation of UV and visible light.An obvious morphological change accompanying with the photochromism was observed in situ. 相似文献
46.
时滞BAM神经网络周期振荡解的存在性和指数收敛性 总被引:1,自引:0,他引:1
应用Banach空间的不动点定理并通过构造适当的Lyapunov函数,结合一些分析的技巧研究了时滞BAM神经网络周期振荡解的存在性和指数收敛性.导出的充分判据无论对网络应用还是设计都具有重要的意义,运用代数的方法易于检验导出的条件.最后,通过实例说明所得结果的有效性, 相似文献
47.
Existence and exponential stability of almost‐periodic solutions for neutral BAM neural networks with time‐varying delays in leakage terms on time scales 下载免费PDF全文
This paper is concerned with neutral bidirectional associative memory neural networks with time‐varying delays in leakage terms on time scales. Some sufficient conditions on the existence, uniqueness, and global exponential stability of almost‐periodic solutions are established. An example is presented to illustrate the feasibility and effectiveness of the obtained results. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
48.
In this paper, the asymptotic property of a class of neutral-type BAM neural networks with time-varying and infinite distributed delays is discussed. By developing a new integral inequality and applying the properties of nonnegative matrix, some sufficient conditions for the Lagrange stability and the existence of the global attracting set of the considering model are obtained. Meanwhile, the estimation of the global attractive set is also given out. The results derived here generalize and improve the earlier publications. Finally, two numerical examples are given and analyzed to demonstrate our results. 相似文献
49.
Gitte Gotholdt Jensen Erland Björklund Allan Simonsen Bent Halling-Sørensen 《Journal of chromatography. A》2009,1216(27):5199-5206
An analytical method was developed for the determination of 2,6-dichlorobenzamide (BAM) and five degradation products thereof including 2-chlorobenzamide (OBAM), 2,6-dichlorobenzoic acid (DCBA), 2-chlorobenzoic acid (OBA), benzoic acid (BA) and benzamide (BAD) in water samples. Solid-phase extraction was combined with liquid chromatography coupled to tandem mass spectrometry using electrospray ionisation. Groundwater spiked at a concentration of 1.0 μg/L gave recoveries on day 1 between 91 and 102% (relative standard deviation: 2.2–26.5%) for OBAM, BAM, DCBA, BA and OBA, while BAD showed a somewhat lower recovery of 60% (relative standard deviation: 25%). Corresponding figures on day 3 gave recoveries of 97–110% (relative standard deviation: 3–22%) for OBAM, BAM, DCBA, BA and OBA, while BAD had a recovery of 51% (relative standard deviation: 4%). The final SPE-LC–MS/MS method had a LODMethod of 0.009, 0.007, 0.010, 0.021, 0.253 and 0.170 μg/L groundwater for BAD, OBAM, BAM, DCBA, BA and OBA and a LOQMethod of 0.030, 0.023, 0.035, 0.071, 0.842 and 0.565 μg/L groundwater in the same order of appearance. Analysis of three different Danish groundwaters confirmed the occurrence of BAM at levels exceeding the threshold value of 0.1 μg/L, while no degradation products were found above LODMethod. 相似文献
50.
Nadia Y. Ashri Mosayeb Daryanavard Mohamed Abdel‐Rehim 《Biomedical chromatography : BMC》2013,27(3):396-403
Microextraction by packed sorbent (MEPS) is a miniaturized, solid‐phase extraction (SPE) technique that works online with gas chromatography (GC) and liquid chromatography (LC). Not only is the automation process with MEPS advantageous, but the much smaller volumes of the samples, solvents and dead space in the system also provide other significant advantages such as the speed and the simplicity of the sample preparation process. In this study MEPS has been evaluated for quantification of sensory neuron‐specific receptors agonist (BAM8‐22). Owing to the instability of BAMs, the focus was on fast extraction and determination of the peptide online using LC‐MS/MS. Sorbents such as C2, C8 and ENV+ (hydroxylated polystyrene–divinylbenzene copolymer) were investigated in the present study. MEPS‐C8 gave the best results compared with C2 and ENV and it was used for the method validation. The calibration curve was obtained within the concentration range of 20.0–3045 nmol/L in plasma. The regression correlation coefficients for plasma samples were ≥0.99 for all runs (n = 6). The between‐batch accuracy and precision for BAM8‐22 ranged from ?13 to ?2.0% and from 4.0 to 14%, respectively. Additionally, the accuracy and precision for BAM22‐8 ranged from ?13 to 7.0% and from 3.0 to 12%, respectively. The present method was used for pharmacokinetic studies for BAMs in plasma samples. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献