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121.
M. Miranda B.V. DorríoJ. Blanco J. Diz-BugarínF. Ribas 《Optics and Lasers in Engineering》2012,50(4):522-528
Two-stage phase shifting algorithms make possible to directly recover the sum or the difference of the optical phase of two different fringe patterns. These algorithms can be built by combining the known phase shifting algorithms in a non-linear way. In this work, we associate a two-dimensional characteristic polynomial to each two-stage phase shifting algorithm. This enables us to qualitatively compare their behaviour against the main systematic error sources, by means of an analysis protocol like that used for phase shifting algorithms. We show that this tool allows to understand the propagation of properties from precursor phase shifting algorithms to new evaluation algorithms built from them. As an experimental application, a wavefront distortion evaluation in differential phase-shifting interferometry is presented. 相似文献
122.
With the availability of fast computers, inline electron holography, a technique for reconstructing both amplitude and phase of the electron wave function as scattered by the sample from a set of differently aberrated transmission electron microscopy images, is becoming increasingly quantitative. While focal series reconstruction from transmission electron microscopy images has already been practiced for at least 3 decades, existing approaches can only recover a relatively small band of spatial frequencies. Here I present a reconstruction scheme which is capable of reconstructing the electron wave function for a very large range of spatial frequencies, demonstrating its performance using simulated as well as experimental data. 相似文献
123.
刘嘉伟 《大连民族学院学报》2016,18(6):552-560
萨都剌是中国古代少数民族文学家的杰出代表,公认的元诗大家。从“文献”“文本”“文化”三个维度对萨都剌研究史进行了梳理。萨都剌作品研究、文化研究方面都取得了可喜的成绩,萨都剌生平、族属、文本归属情况依旧存在争议,尚期待新文献的发现与习见文献辨伪、辩误的深入。未来,可以深入探讨萨都剌的文学成就对于整部“中华文学史”的贡献,并且期待能够运用多学科、跨学科的视角与方法对这位色目才子进行全面的解读。 相似文献
124.
激发阅读兴趣,培养学生的审美能力和人文素质是中国现当代文学教学改革的重心。文本细读是走进文学本身魅力的一大途径,是中国现当代文学教学改革的基本路径。文本细读教学法是文本细读在文学史教学过程中的具体应用,也是现当代文学教学改革的基本方法。 相似文献
125.
Jamilson R. Campos 《Linear and Multilinear Algebra》2013,61(3):322-346
Considering the successful theory of multiple summing multilinear operators as a prototype, we introduce the classes of multiple Cohen strongly p-summing multilinear operators and polynomials. The adequacy of these classes under the viewpoint of the theory of multilinear and polynomial ideals and holomorphy types is discussed in detail. 相似文献
126.
安卫华 《科技情报开发与经济》2014,(16):101-104
对比分析了中美儿童分级阅读在研究主体、研究方法、研究应用上的差异,总结出我国儿童分级阅读的研究现状及出现的问题。提出了借鉴美国经验、立足我国国情开展儿童分级阅读的途径,包括组成多学科研究团队、制定科学的分级标准、全方位深入应用到儿童阅读教育中。 相似文献
127.
K. Yano 《SAR and QSAR in environmental research》2013,24(1):15-26
Abstract A method for a preliminary survey of the relationship between molecular structure and performance was described using 1506 random data of structure-acute toxicity for mice (intravenously dosed). The structural patterns of the weakest toxic structures (111) were extracted from the data and the patterns discriminated for 64.2% of the other structures (1395). As for the 826 structures of strongest toxicity, 78.3% were discriminated by these structural patterns. These results were obtained by using structural parameter ratios to describe the structural patterns and the exhaustive elimination process to select the best parameter ratio from many candidates. The results were summarized in the form of a chart which can be used for practical screening for the weakest toxic structures. 相似文献
128.
芶清泉 《原子与分子物理学报》2011,28(5):785-788
我在一篇论文中提出了一个冷聚变的全原子论,阐明氘原子进入钯晶体间隙位置时扩展成为一个封闭的球形全原子,其价电子完全在球内,围绕氘核运动使氘核对邻近氘核的排斥作用被屏蔽掉,使氘核易于接近而产生聚变。对离子晶体两个负氘离子相互作用是怎样引起聚变的没做详细讨论,本文将对此问题进一步进行详细讨论。 相似文献
129.
We formulate a sufficient condition for the existence of a consistent price system (CPS), which is weaker than the conditional full support condition (CFS). We use the new condition to show the existence of CPSs for certain processes that fail to have the CFS property. In particular this condition gives sufficient conditions, under which a continuous function of a process with CFS admits a CPS, while the CFS property might be lost. 相似文献
130.
E. Almasi N. Kirshen H. Kern 《International journal of environmental analytical chemistry》2013,93(1-4):39-48
Abstract Trace level Volatile Organic Compounds (VOCs) in ambient air are normally determined according to EPA Method TO-14. This method describes the analysis in ambient air of 41 VOCs, ranging in boiling point from -29 to 215°C. It covers a concentration range from 0.2 to 20 parts per billion, volume/volume (ppb), and specifies sample enrichment of a 400 mL air sample on glass beads at -160°C. While this sample volume provides sub-ppb levels of VOC detection for target analytes when using a quadrupole mass spectrometer detector in SIM mode or when using GC detectors, the identification of non-target analytes may only be done in full scan mode for higher concentrations. Also with this sample volume a Nafion dryer is needed for water removal thereby lowering the recovery of polar VOCs. Because of the very high sensitivity of the ion trap MS, relatively small air volumes (60 mL) are adequate to obtain the required or lower detection levels. An integrated air analysis system based on a GC-ion-trap MS has been investigated and is described. This system has a built-in cryogenic trap and necessary valving, internal standard gas sampling loop, and is controlled from the GC-MS workstation. The linearity, precision, and method detection levels obtainable with this system when using small volumes are reported. In addition, examples of the quantitative and qualitative analysis of ambient air samples are shown. 相似文献