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961.
The exponential p-moment stability of stochastic impulsive differential equations is addressed. A new theorem to ensure the p-moment stability is established for the trivial solution of the stochastic impulsive differential system. As an application
of the theorem proposed, the problem of controlling chaos of Lorenz system which is excited by parameter white-noise excitation
is considered using impulsive control method. Finally, numerical simulation results are given to verify the feasibility of
our approach.
Supported by the National Natural Science Foundation of China (Grant No. 10772046) 相似文献
962.
WeiWei Ji Ning Cai Ying Zhao XiaoDan Zhang Jian Sun ChangChun Wei CunDa Yuan Yuan Li Yan Su ShaoZhen Xiong 《中国科学E辑(英文版)》2009,52(7):1923-1927
A new type counter electrode for dye-sensitized solar cells (DSCs) was proposed which consists of substrate, aluminum film
and platinum film. The new type counter electrode can obviously improve the photoelectric conversion efficiency of DSCs from
3.46% to 7.07% under the standard AM1.5 irradiation condition. Advantages and shortcomings of this new type counter electrode
in terms of electrical properties, optical properties and anti-corrosive properties were analyzed. As a result, some improvements
were proposed.
Supported by the Key Foundation for Fundamental Research of Tianjin Municipal Science & Technology Commission in China ( Grant
No. 06YFJZJC01700) and the National Basic Research Program of China (“973“ Project) (Grant Nos. 2006CB20260, 2006CB202603) 相似文献
963.
Synthetic aperture interferometric technique has wide applications in optics, radio astronomy and microwave remote sensing
areas. With the increasing demands of high resolution imaging observation, a new time-sharing sampling scheme of asynchronous
rotation scan is proposed to meet the technical challenge of achieving a large equivalent aperture and overcome the operating
barriers of space borne application. This configuration is basically composed by two asynchronously and concentrically rotating
antenna groups, whose revolving radii and speeds are different. The synthetic aperture system with asynchronous rotation scanning
scheme can effectively solve the trade-off problem of system complexity, and greatly simplify the system hardware at the cost
of sacrificing a certain time resolution. The basic rules and design methods of asynchronous rotation scan are investigated
The Gridding method is introduced to inverse the spiral sampling data for image reconstruction. The potential applications
of geostationary orbit (GEO) earth observation and solar polar orbit (SPO) plasma cloud observation are explored with numerical
simulations to validate the significance and feasibility of this new imaging configuration.
Supported by the National Natural Science Foundation of China (Grant No. 40574070, 40671121, 40701100 and 40801136) and the
National High-Tech Research Program of China (“863” Program) (Grant No. 2006AA12Z141) 相似文献
964.
Variability of complementary relationship and its mechanism on different time scales 总被引:1,自引:0,他引:1
In the complementary relationship (CR) between actual and potential evapotranspiration, wet envi- ronment evapotranspiration (Ew) is usually calculated using the Priestley-Taylor (P-T) equation. Based on the data obtained from 38 catchments of the Haihe River basin and the Weishan experiment site in Shandong Province of China, this study has found variations in the Priestley-Taylor parameter α (e.g. increase in values with increase in the amount of precipitation on annual scale, seasonal fluctuation noted t... 相似文献
965.
966.
967.
研究在不同的夹持距离、不同拉伸速率条件下涤纶低弹网络丝机械性能 ,从实验结果得知 ,在相同拉伸速率下 ,断裂强力随夹持距离的增加呈对数关系减少。在相同夹持距离下 ,随着拉伸速率的提高 ,平均断裂强力提高 ,断裂伸长增大 ,断裂比功也增大。 相似文献
968.
969.
SARS灭活疫苗的研制及其质量控制 总被引:2,自引:0,他引:2
目的研究适合SARS病毒灭活疫苗的生产工艺及其质量控制。方法连续制备3批疫苗,按拟定规程进行疫苗原液和疫苗各项指标检测。结果各项检测指标均符合拟定规程规定。结论我所生产的SARS灭活疫苗工艺稳定,质量可控。 相似文献
970.