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31.
Qingzhao Yao Yuming Zhou Yanqing Sun Xiaoyun Ye 《Journal of Inorganic and Organometallic Polymers and Materials》2008,18(4):477-484
TiO2 hybrid molecular imprinted polymer (MIP) for ethofumesate using methacrylic acid (MAA) as the functional monomer and silane
coupling agent 3-(trimethoxysilyl) propylmethacrylate (KH570) as organic–inorganic connective bridge was synthesized via photo-excitation
method. Hydrogen bond was proved to act between MAA and ethofumesate for pre- and post-polymerization binding properties as
testified by UV spectrometric method. KH570 modified TiO2 nanoparticles were prepared via sonochemical reaction, which can accelerate hydrolysis, increase collision chance for the
reactive system and improve the dispersion of the nanoparticles. Scanning electron microscope (SEM), transmission electron
microscope (TEM), binding and the adsorption kinetics experiments as well as thermogravimetric analysis (TGA) were employed
for characterization. The results indicated that the hybrid MIP revealed a larger surface area and more ordered imprinting
cavities with improved thermal stability compared to organic-only MIP. Furthermore, faster adsorption kinetics and enhancive
adsorption capacity were achieved, which made it promising in chemical sensor applications. 相似文献
32.
Haijun Fang Zongli Lin 《Automatic Control, IEEE Transactions on》2006,51(7):1177-1184
In this note, we revisit the problem of global practical stabilization for planar linear systems subject to actuator saturation and input additive disturbances. A parameterized linear state feedback law is designed such that, by tuning the value of the parameter, all trajectories of the closed-loop system converge to an arbitrarily small neighborhood of the origin in a finite time and remain in there. 相似文献
33.
34.
Wei Li Zhang Wei Pan Bin Luo Xi Hua Zou Meng Yao Wang 《Photonics Technology Letters, IEEE》2008,20(9):712-714
A theoretical construction of one-to-many (OTM) and many-to-one (MTO) chaos synchronization communications using semiconductor lasers is presented. One center laser provides strong injections (strong link) to other side lasers, and the side lasers also provide weak injections (weak link) to the center one. Simulation results show that the side lasers synchronize with the center laser through injection-locking. In addition, messages transmitted via the strong links or the weak links experience strong chaos pass filtering, enabling us to realize OTM and MTO communications. 相似文献
35.
36.
Evolving artificial neural network ensembles 总被引:3,自引:0,他引:3
Using a coordinated group of simple solvers to tackle a complex problem is not an entirely new idea. Its root could be traced back hundreds of years ago when ancient Chinese suggested a team approach to problem solving. For a long time, engineers have used the divide-and-conquer strategy to decompose a complex problem into simpler sub-problems and then solve them by a group of solvers. However, knowing the best way to divide a complex problem into simpler ones relies heavily on the available domain knowledge. It is often a manual process by an experienced engineer. There have been few automatic divide-and-conquer methods reported in the literature. Fortunately, evolutionary computation provides some of the interesting avenues to automatic divide-and-conquer methods. An in-depth study of such methods reveals that there is a deep underlying connection between evolutionary computation and ANN ensembles. Ideas in one area can be usefully transferred into another in producing effective algorithms. For example, using speciation to create and maintain diversity had inspired the development of negative correlation learning for ANN ensembles, and an in-depth study of diversity in ensembles. This paper will review some of the recent work in evolutionary approaches to designing ANN ensembles. 相似文献
37.
Mixtures of Cr and Mo elemental powders, with the nominal compositions Cr25Mo75, Cr50Mo50, and Cr75Mo25, are processed by high-energy ball milling at ambient temperature. Milling is observed to force the mixing of the immiscible
bcc elements Cr and Mo into solid solutions. The lattice parameter of these solid solutions, measured by X-ray diffraction
(XRD), displays the expected positive deviation from Vegard’s law. These deviations are compared to the ones predicted by
Eshelby’s inclusion model for dilute alloys. The conventional Williamson-Hall approach is shown to fail to determine the grain
size in as-milled samples, probably due to the high density of dislocations. Annealing at 700 °C for 10 hours under argon
leads to a large reduction in structural defect density, without inducing any significant decomposition. The mixing measured
in Cr-Mo is discussed in the broader context of the mechanical mixing forced by ball milling in moderately immiscible systems. 相似文献
38.
基于DSP的电力数据采集平台的设计与研究 总被引:1,自引:0,他引:1
介绍了一种用于电力系统的数据采集系统.该系统采用数字信号处理器(DSP)和复杂可编程逻辑器件(CPLD)作为核心芯片,给出了主要部分的电路及其原理、功能,系统中使用CPLD实现基本逻辑,使系统有足够的冗余和灵活性,具有可靠性高、可升级等优点. 相似文献
39.
40.
Fang Wu Yaojiang Zhang Zaw Zaw Oo Erping Li 《Antennas and Propagation Magazine, IEEE》2005,47(4):110-118
The Multilevel Fast Multipole Method (FMM) is a well-established method and can be applied to solve electromagnetic (EM) scattering problems. Compared with other traditional methods, it requires less computational time and memory. However, constrained by a single processor's speed and memory limitations, the problem size that can be solved by serial implementation is still relatively small. For a million-unknown target, the computational time on a single processor is intolerable, and memory could be easily exhausted. Parallel-computing technology, which can utilize multiprocessors, provides an efficient way to solve electrically large-scale EM problems. This paper will focus on discussing the parallel methodologies applied to a multilevel FMM code, as well as demonstrating the computational efficiency of the parallel approach. 相似文献