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101.
X. Zhang 《Applied Mathematics and Optimization》2000,41(2):155-170
In this paper we obtain two exact internal controllability results of Maxwell's equations in a general region by using multiplier
techniques. The first one is exact controllability in a short time, in which we obtain the ``optimal" (observability) estimates
when the location and the shape of the controller is fixed. What happens if we allow the controller to change? Under some
conditions, we show that by doing that the system can be exactly controllable within any given time duration, which is our
second exact controllability result.
Accepted 30 September 1998 相似文献
102.
C. Reylé P. Bréchignac 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2000,8(2):205-210
Fluorescence spectra of naphthalene, C10H8, were obtained in the laboratory under conditions which provide an appropriate simulation of the cometary conditions: super-cooled
gas phase molecules in a collision-free environment. Five spectra were recorded, the excitation energies ranging from 1422
to 5293 cm−1 above the first electronic state S1 at 32 020 cm−1. A comparison with previous jet-cooled naphthalene fluorescence spectra obtained by Beck et al. [1] and Hermine [2] shows that the former results are not consistent with the present ones. Spectra obtained by Beck et al. show weaker intensities at greater wavelengths compared to those obtained by Hermine and ourselves. We also measured the
fluorescence lifetimes by recording the fluorescence decay as a function of time after the excitation of the molecules by
monochromatic lasers and deduced the fluorescence quantum yields. A synthetic emission spectrum under solar irradiation is
obtained for astrophysical implications. 相似文献
103.
利用基于近场光学原理构建的全内反射荧光显微镜研究了大鼠单个心肌细胞中的钙信号. 利用这种显微镜的快速成像和高信噪比的特点,观察到单个细胞中复杂的二维钙波斑图. 分析了单个钙信号释放事件在钙波形成、运动过程中的作用. 建立在fire-diffuse-fire模型基础上的模拟显示,由基本钙释放事件组成的钙波可以在心肌细胞中稳定存在. 此研究对进一步认识活体可激发系统的微观动力学行为有指导意义.
关键词:
近场光学
全内反射荧光显微镜
心肌细胞
钙波 相似文献
104.
阐述了利用水果制作原电池进而测定电池的电动势和内阻的理化实验课的协同教学过程,并对教学效果进行了反馈.通过教学后思考总结了协同教学的优点,并对进一步实施提出了注意事项. 相似文献
105.
C. Garcıa-Recio J. Nieves L. L. Salcedo 《The European Physical Journal A - Hadrons and Nuclei》2007,31(4):540-542
Starting from a consistent SU(6) extension of the Weinberg-Tomozawa (WT) meson-baryon chiral Lagrangian ( Phys. Rev. D 74, 034025 (2006)), we study the s-wave meson-baryon resonances in the strangeness S = - 3 and negative-parity sectors. Those resonances are generated by solving the Bethe-Salpeter equation with the WT interaction
used as kernel. The considered mesons are those of the 35-SU(6)-plet, which includes the pseudoscalar (PS) octet of pions and the vector (V) nonet of the rho-meson. For baryons we consider
the 56-SU(6)-plet, made of the 1/2+ octet of the nucleon and the 3/2+ decuplet of the Delta. Quantum numbers I(J
P) = 0(3/2-) are suggested for the experimental resonances Ω
*(2250)- and Ω
*(2380)-. Among other, resonances with I = 1 are found, which minimal quark content is sssˉl', being s the strange quark and l, l' any of the the light up or down quarks. A clear signal for such a pentaquark would be a baryonic resonance with strangeness -3 and electric charge -2 or
0, in proton charge units. We suggest looking for K
-
Ξ
- resonances with masses around 2100 and 2240MeV in the sector 1(1/2-), and for π
±
Ω
- and K
-
Ξ
*- resonances with masses around 2260MeV in the sector 1(3/2-). 相似文献
106.
YAO Lan YANG Bo 《中国电子科技》2007,5(1):23-28
Due to the rapid development of computers and their applications,early software quality prediction in software industry becomes more and more crucial. Software quality prediction model is very helpful for decision-makings such as the allocation of resource in module verification and validation. Nevertheless,due to the complicated situations of software development process in the early stage,the applicability and accuracy of these models are still under research. In this paper,a software quality prediction model based on a fuzzy neural network is presented,which takes into account both the internal factors and external factors of software. With hybrid-learning algorithm,the proposed model can deal with multiple forms of data as well as incomplete information,which helps identify design errors early and avoid expensive rework. 相似文献
107.
108.
109.
利用渗流技术制备出了以石墨颗粒为阻尼增强相、以Cu-11.9Al-2.5Mn(wt%)形状记忆合金为基体的复合材料,对该合金的内耗行为进行了研究. 在淬火态样品的内耗-温度曲线上观察到两个内耗峰,分别位于240 ℃和370 ℃附近. 对其中低温峰的变化规律和机理进行了研究. 实验发现,低温峰仅在复合材料中出现,峰位与频率无关,峰高随频率升高而上升;随升温速率增加,峰高增加,峰位移向高温;随石墨颗粒体积分数增加,峰高增加;经多次热循环后该内耗峰消失. 由以上特征和微观观察,可以证明该峰起因于外加交变应力与位错的相互作用. 相似文献
110.