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991.
Yolanda Moreno 《Applied Categorical Structures》2008,16(5):617-627
We obtain new categorical proofs that generalize the diagonal principles introduced in Castillo and Moreno (Israel J. Math.
140:253–270, 2004) to study the automorphic and partially automorphic character of Banach spaces. We then introduce and study the automorphy
index for a Banach space, showing that while .
This research has been supported in part by project MTM2004-02635. 相似文献
992.
Leyva I Sevilla-Escoboza R Buldú JM Sendiña-Nadal I Gómez-Gardeñes J Arenas A Moreno Y Gómez S Jaimes-Reátegui R Boccaletti S 《Physical review letters》2012,108(16):168702
Critical phenomena in complex networks, and the emergence of dynamical abrupt transitions in the macroscopic state of the system are currently a subject of the outmost interest. We report evidence of an explosive phase synchronization in networks of chaotic units. Namely, by means of both extensive simulations of networks made up of chaotic units, and validation with an experiment of electronic circuits in a star configuration, we demonstrate the existence of a first-order transition towards synchronization of the phases of the networked units. Our findings constitute the first prove of this kind of synchronization in practice, thus opening the path to its use in real-world applications. 相似文献
993.
In this paper, we show how the coupling of light into a photonic crystal waveguide can be greatly enhanced by creating a periodic modulation in the dielectric structure surrounding the entrance of the waveguide. In this way, surface modes supported by the system can funnel the light that impinges onto the surface into the interior of the waveguide. Moreover, we also demonstrate that the shape and direction of the beam that emerges from the structure can be tailored by constructing a periodic corrugation near the exit side of the waveguide. 相似文献
994.
光学测量中椭圆圆心定位算法研究 总被引:8,自引:1,他引:8
提出了一种椭圆圆心定位算法。先对图像中的椭圆目标进行粗定位,获取椭圆的粗定位信息,再用Canny算子对图像中的感兴趣区域进行边缘检测。根据椭圆的粗定位信息以及图像的边缘灰度分布特征,用高斯曲线拟合的方法求得精确的亚像素边缘点的坐标。针对亚像素边缘点中出现的“孤立点”以及噪声点,分别用曲率滤波和均值滤波的方法加以滤波,将滤波后的亚像素边缘点用最小二乘法加以拟合,求得精确的椭圆圆心数据。实验证明了该算法的定位精度和抑制噪声能力,通过测试算法运行时间,证明该算法具有很好的实时性。 相似文献
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999.
Dell Farnan George Tony Moreno John Stults Andreas Becker Guillaume Tremintin Mark van Gils 《Journal of chromatography. A》2009,1216(51):8904-8909
Size exclusion chromatography is a widely performed analysis of monoclonal antibodies, primarily used to monitor the levels of higher weight molecular species such as aggregates. Owing to the subtleties of these separation mechanisms and frequently observed partial resolutions of components in these separations, many common methods for increasing the method throughput are not practical as they trade off resolution for speed. Short columns, high flow rates and smaller particles are examples of these approaches. In this paper a practical method is demonstrated for injecting samples onto the column in rapid succession and gating the detection window to monitor the elution of each sample individually. At any given instant approximately two samples are eluting through the column. By co-ordinating the injection and detection time windows the samples can be kept discrete and significant throughput enhancements achieved, up to nearly 2-fold improvements are demonstrated. A rudimentary theory is development to show that the throughput improvements can be predicted to approximation by simple column characteristics. Experimental results for a series of monoclonal antibodies demonstrate the equivalency of the method to a conventional injection approach, the throughput increase, and the robustness of the method. 相似文献
1000.
Pablo Moreno Marco Rossetti Benoît Deveaud-Plédran Andrea Fiore 《Optical and Quantum Electronics》2008,40(2-4):217-226
By means of an electron hole rate equation model we explain the phase dynamics of a quantum dot semiconductor optical amplifier and the appearance of different decay times observed in pump and probe experiments. The ultrafast hole relaxation leads to a first ultrafast recovery of the gain, followed by electron relaxation and, in the nanosecond timescale, radiative and non-radiative recombinations. The phase dynamics is slower and is affected by thermal redistribution of carriers within the dot. We explain the ultrafast response of quantum dot amplifiers as an effect of hole escape and recombination without the need to assume Auger processes. 相似文献