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51.
Generalized KKM Type Theorems in FC-Spaces with Applications (I) 总被引:1,自引:0,他引:1
Xie Ping Ding 《Journal of Global Optimization》2006,36(4):581-596
The class KKM(X,Y) (resp., s-KKM(X,Y,Z)) of set-valued mappings with KKM (resp., s-KKM) property is introduced in FC-spaces without any convexity structure. Some generalized KKM (resp., s-KKM) type theorems are proved in FC-spaces under much weak assumptions. As applications, some new section theorems and coincidence theorems are established in FC-spaces. These theorems generalize many known results in literature. The further applications of these results will be given in a follow-up paper. 相似文献
52.
53.
Xie Zhijian Tan Qiulin 《International Journal of Infrared and Millimeter Waves》2006,27(12):1639-1649
To counter the problems of gas accidents in coal mines, family safety resulted from using gas, a new infrared detection system
with integration and miniaturization has been developed. The infrared detection optics principle used in developing this system
is mainly analyzed. The idea that multi gas detection is introduced and guided through analyzing single gas detection is got
across. Through researching the design of cell structure, the cell with integration and miniaturization has been devised.
The way of data transmission on Controller Area Network (CAN) bus is explained. By taking Single-Chip Microcomputer (SCM)
as intelligence handling, the functional block diagram of gas detection system is designed with its hardware and software
system analyzed and devised. This system designed has reached the technology requirement of lower power consumption, mini-volume,
big measure range, and able to realize multi-gas detection. 相似文献
54.
55.
Large-eddy-simulation of 3-dimensional Rayleigh-Taylor instability in incompressible fluids 总被引:1,自引:0,他引:1
The 3-dimensional incompressible Rayleigh-Taylor instability is numerically studied through the large-eddy-simulation ( LES)
approach based on the passive scalar transport model. Both the instantaneous velocity and the passive scalar fields excited
by sinusoidal perturbation and random perturbation are simulated. A full treatment of the whole evolution process of the instability
is addressed. To verify the reliability of the LES code, the averaged turbulent energy as well as the flux of passive scalar
are calculated at both the resolved scale and the subgrid scale. Our results show good agreement with the experimental and
other numerical work. The LES method has proved to be an effective approach to the Rayleigh-Taylor instability. 相似文献
56.
Xie Ruixiang Wang Min Duan Changchun Yan Yihua R. A. Sych A. T. Altyntsev 《中国科学A辑(英文版)》2002,45(1):97-105
A complex solar radio moving type IV burst was observed on 23 September 1998 with the broadband (1.0–2.0 GHz and 2.6–3.8 GHz) spectrometers with high temporal and spectral resolutions at National Astronomical Observatories of China (NAOC). Comparing to the high spatial resolution data of Siberian Solar Radio Telescope (SSRT), we find that this burst is a rare type of moving type IV burst which is caused by the expanding arches, and the spatial structure oscillations of the radio sources are related with the time structure pulsations of the radio emission. Furthermore, the burst is associated with the multiple quasi-periodic long-term pulsations, and this suggests the existence of multi-scale magnetic structures in a large expanding coronal arch. We think the moving type IV burst is due to the synchrotron emission of the energetic electrons trapped in the expanding arch, and the multiple quasi-periodic pulsations are due to the second harmonic plasma emission. 相似文献
57.
采用矩阵奇异值分解(singular value decomposition, SVD)的方法,对高温射频超导量子干涉仪(HTc rf-SQUID)采集到的单通道心磁信号进行处理.证明了对于近似周期性的心磁信号,在无参考噪声的情况下矩阵奇异值分解的方法与自适应窄带陷波相结合有较好的消除广谱噪声的效果.
关键词:
高温射频超导量子干涉仪
心磁信号
奇异值分解
噪声消除 相似文献
58.
1IntroductionThispaperisconcernedwithpositivesolutionOfthesemilinearheatequationswithlocalizedreactionssubjecttoeitherinitialconditions(Cauchyproblem)ortheinitialandboundary-value(DirichletorNeumanntype)conditionswherenisaboundeddomaininRe,icEO.Equations(1.1)canbethoughtofasamodeltodescribesomephysicalphenomena(heatpropagation,chemicalreaction)inwhichthenonlinearreactionsinadynndcalsystemtakesplaceonlyatasinglesite.InthesequelforconvenienceweshallsamplycalltheCauchy,initial-Direchlet,orini… 相似文献
59.
凸集的广义Reuleaux三角形 总被引:1,自引:1,他引:0
常宽凸集的面积最小者为Reulaux三角形,而非常宽凸集的面积最小者为何呢?它就是本文将给出的广义Reuleaux三角形△R。 相似文献
60.
谢家麟 庄杰佳 黄永章 张令翊 林绍波 赵春农 李立华 吴钢 王钢 李承泽 傅恩生 苏憬 钟元元 王言山 李永贵 应润杰 杨学平 李有猛 韩斌 吴庆武 张玉珍 潘卫民 王建伟 张黎文 郭康柱 畅祥云 李亚南 戴立盛 徐金强 陆辉华 汪伯嗣 任廉重 田瑞生 《中国物理 C》1994,18(8):763-768
北京自由电子激光(BFEL)装置于1993年底在10.68μm处实现了饱和振荡.输出激光能量为3mJ,饱和平顶宽度2μs.对应饱和振荡平均功率为210kW(宏脉冲),峰值功率约为20MW,比自发辐射高8个量级,单程小讯号净增益为24%,转换效率为0.45%,与理论预期结果相符.光束质量接近衍射极限.目前装置可工作于9-11μm. 相似文献