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251.
Structural features of toxic chemicals for specific toxicity 总被引:1,自引:0,他引:1
We have studied the structural features of toxic chemicals from the RTECS database associated with specific toxicity. The frameworks, functional groups, and structure patterns of molecules are taken into account. Potential active frameworks, groups, and structure patterns for specific toxicity are gained by computational chemistry approaches. These structural features of toxic chemicals will be helpful in understanding activities of toxic chemicals and useful in predicting the toxicity of chemicals, especially in the early stage of drug design. 相似文献
252.
Taherion S Lai YC 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》1999,59(6):R6247-R6250
Lag synchronization is a recently discovered theoretical phenomenon where the dynamical variables of two coupled, nonidentical chaotic oscillators are synchronized with a time delay relative to each other. We investigate experimentally and numerically to what extent lag synchronization can be observed in physical systems where noise is inevitable. Our measurements and numerical computation suggest that lag synchronization is typically destroyed when the noise level is comparable to the amount of average system mismatch. At small noise levels, lag synchronization occurs in an intermittent fashion. 相似文献
253.
Zhou C Lai CH 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》1999,59(6):6629-6636
It has been proposed to realize secure communication using chaotic synchronization via transmission of a binary message encoded by parameter modulation in the chaotic system. This paper considers the use of parameter adaptive control techniques to extract the message, based on the assumptions that we know the equation form of the chaotic system in the transmitter but do not have access to the precise values of the parameters which are kept secret as a secure set. In the case in which a synchronizing system can be constructed using parameter adaptive control by the transmitted signal and the synchronization is robust to parameter mismatches, the parameter modulation can be revealed and the message decoded without resorting to exact parameter values in the secure set. A practical local Lyapunov function method for designing parameter adaptive control rules based on originally synchronized systems is presented. 相似文献
254.
我们发现可以把二元多项式盾成系数为一元多项式的一元多项式来进行分解,据此,本文建立了二元整系数多项式因式分解的一种理论,提出了一个完整的分解二元整系数多项式的算法。这个算法还能很自然地推广成分解多元整系数多项式的算法。 相似文献
255.
An exact analysis is given to explain the experimental results of Su et al. The resolving power is shown to vary from extremely good to worse than that based on the Rayleigh criterion, depending upon the location of the illuminated area on the hologram during reconstruction. 相似文献
256.
C.S. Lai 《Physics letters. A》1979,70(1):6-8
It is shown that the soliton-like solution to the nonlinear Schrödinger equation perturbed by resonance interaction can be derived by a straightforward perturbation calculation. 相似文献
257.
The strong consistency of least squares estimates in multiple regression models is established under minimal assumptions on the design and weak dependence and moment restrictions on the errors. 相似文献
258.
The stability of a curved rail under a constant moving load has been investigated using a linear theory; critical speeds of the moving load, and the dynamic rail deflections and rotation were calculated. The effect of the foundation was included through distributed linear springs. It was assumed that the moving load remains in constant contact with the rail and travels along a fixed path on the rail head. 相似文献
259.
Field theories naturally give rise to multiple jets of hadrons in short-distance processes, such as e+ e? annihilation. In particular, a low-energy jet of hadrons distributed in some cone of opening angle δ would be naively expected to evolve at high energies into multiple jets within the angle δ. We explore to what extent this will happen in quantum chromodynamics. 相似文献
260.