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The European corn borer Ostrinia nubilalis (ECB; Lepidoptera: Crambidae) is a widely recognized pest of agricultural significance over much of the northern hemisphere. Because of the potential value of pheromone-based control, there has been considerable effort devoted to elucidation of the ECB chemical ecology. The species is polymorphic regarding its female-produced pheromone. Partly because of this feature, over the years the ECB has become a model to study pheromone evolution. This review should assist in identifying new areas of pheromone research by providing an overview of the literature produced on this subject for the ECB since the late 1960’s.  相似文献   
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详细介绍了泰国曼谷南外环线上主垮500 m的SOBRR叠合梁斜拉桥的主要施工方法,如节段的安装,悬臂施工主梁的水平锚固、边墩和边主梁联结、边跨平衡重及主跨的合龙等.  相似文献   
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Analysis of electrocardiograms during atrial fibrillation   总被引:1,自引:0,他引:1  
The research discussed in this article is motivated by the search for an optimal classification of the different types of atrial fibrillation (AF) on the basis of recorded atrial signals. This would facilitate the selection of an optimal therapy. This article focuses on the biophysical models of the genesis of ECG waveforms during AF. The model of the electric activity of the atria was found to have sufficient realism to be used to describe the electric sources during AF. The inclusion of the volume conduction model resulted in electrocardiographic signals that are in all aspects similar to those observed clinically. The model is currently applied to solve various problems related to optimal signal preprocessing and extraction of features in AF signals for the classification of AF abnormalities. The biophysical model of the atrial activity is an essential element in this research, since it is capable of describing the electric source specifications derived from different hypotheses relating to the etiology of AF  相似文献   
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The damage induced in 3C-SiC epilayers on a silicon wafer by 2.3-MeV Si ion irradiation for fluences of 1014, 1015, and 1016 cm−2, was studied by conventional and high-resolution transmission electron microscopy (TEM/HRTEM). The evolution of extended defects and lattice disorder is followed in both the 3C-SiC film and Si substrate as a function of ion fluence, with reference to previous FTIR spectroscopy data. The likelihood of athermal unfaulting of native stacking faults by point defect migration to the native stacking faults is discussed in relation to damage recovery. Threshold energy densities and irradiation doses for dislocation loop formation and amorphous phase transformation are deduced from the damage depth profile by nuclear collisions. The role of electronic excitations on the damage recovery at high fluence is also addressed for both SiC and Si.  相似文献   
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We have investigated the transport properties, resistivity and Hall effect, in a series of underdoped GdBa 2 Cu 3 O x thin films grown by off-axis magnetron sputtering. We find a systematic correlation between the critical temperature T c and the inverse Hall constant R H -1 , related, in simple models, to the carrier concentration n. Our experimental thin film T c (n) data are in good agreement with the temperature-doping phase diagram obtained for YBa 2 Cu 3 O x single crystals. By measuring the activation energies in the liquid vortex phase, and by using a 2-dimensional model for vortex dynamics, we have extracted the penetration depth of these samples, and studied the relation between the carrier concentration and the superfluid density to probe the role of phase fluctuations on superconductivity.  相似文献   
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International Journal on Document Analysis and Recognition (IJDAR) - Motivated by increasing possibility of the tampering of genuine documents during a transmission over digital channels, we focus...  相似文献   
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