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101.
In this brief letter, we modify the classic social force model of Helbing which is applied to simulate how a pedestrian gets outside a hall full of smoke. As the Vicsek model does, the view radius is introduced to describe the range the pedestrian can see. The relation between the evacuation time and the view radius is studied with different numbers of pedestrians. The results show that the shorter the view radius is, the more time walkers will spend escaping, and even fail to escape. And the relation between the number of remaining walkers and the view radius shows non-monotonicity, if the number of pedestrians is larger than 600. And lastly, we propose to enlarge the width of the exit or to add two small exits in the corners, which may decrease the evacuation time greatly and obviously reduce the number of remaining walkers.  相似文献   
102.
High precision rotational spectra of isotopic oxygen O2 (with View the MathML source" title="View the MathML source" src="http://ars.sciencedirect.com/content/image/1-s2.0-S0022407309003872-si0113.gif"> or View the MathML source" title="View the MathML source" src="http://ars.sciencedirect.com/content/image/1-s2.0-S0022407309003872-si0114.gif">) in its View the MathML source" title="View the MathML source" src="http://ars.sciencedirect.com/content/image/1-s2.0-S0022407309003872-si0115.gif"> electronic ground state have been measured in selected frequency regions between 0.4 and 2.0 THz. The main isotopic species, View the MathML source" title="View the MathML source" src="http://ars.sciencedirect.com/content/image/1-s2.0-S0022407309003872-si0116.gif">, was also investigated in its first excited electronic state View the MathML source" title="View the MathML source" src="http://ars.sciencedirect.com/content/image/1-s2.0-S0022407309003872-si0117.gif">. The new data, analyzed together with previous measurements, yielded improved spectroscopic parameters.  相似文献   
103.
104.
The Kpp system is investigated using a variational approach with realistic two-body interactions: the Argonne v18 NN potential and an energy dependent View the MathML source" title="View the MathML source" align="absbottom" border="0" height=14 width="29"/> effective interaction derived from chiral SU(3) coupled-channel dynamics. Uncertainties in subthreshold extrapolations of the View the MathML source" title="View the MathML source" align="absbottom" border="0" height=14 width="29"/> interaction are considered. A weakly bound Kpp state is found, with a binding energy B=(19±3) MeV substantially smaller than suggested in previous calculations. The decay width Γ(KppπΣN) is estimated to range between about 40 and 70 MeV.  相似文献   
105.
Free navigation of a scene requires warping some reference views to some desired target viewpoint and blending them to synthesize a virtual view. Convolutional Neural Networks (ConvNets) based methods can learn both the warping and blending tasks jointly. Such methods are often designed for moderate inter-camera baseline distance and larger kernels are required for warping if the baseline distance increases. Algorithmic methods can in principle deal with large baselines, however the synthesized view suffers from artifacts near disoccluded pixels. We present a hybrid approach where first, reference views are algorithmically warped to the target position and then are blended via a ConvNet. Preliminary view warping allows reducing the size of the convolutional kernels and thus the learnable parameters count. We propose a residual encoder–decoder for image blending with a Siamese encoder to further keep the parameters count low. We also contribute a hole inpainting algorithm to fill the disocclusions in the warped views. Our view synthesis experiments on real multiview sequences show better objective image quality than state-of-the-art methods due to fewer artifacts in the synthesized images.  相似文献   
106.
The 3D extension of high efficiency video coding (3D-HEVC) adopts a view synthesis optimization (VSO) technique to improve the quality of synthesized views for depth map coding. The exact synthesized view distortion change (SVDC) is calculated in VSO which in turn brings huge coding complexity to the 3D-HEVC encoder due to the real view synthesis process. This work presents a scheme aimed at reducing coding complexity of the SVDC calculating process in the 3D-HEVC encoder. It skips line segments of pixels with variable lengths based on information from both of the textures and depth maps in the SVDC calculation. Experimental results demonstrate that the proposed scheme can reduce the coding complexity without any significant loss in rate distortion performance for the synthesized views.  相似文献   
107.
叶红  蔡向东 《信息技术》2002,(6):31-31,72
员工测评系统(以下简称系统)是利用计算机数据库及网络的优质,由计算机统计员工的得分和名次,使原来繁琐的统计和录入工作变得快捷而准确,为动态用工制度提供有力的依据。  相似文献   
108.
A variety of convolution inequalities have been obtained since Anderson's theorem. ?In this paper, we extend a convolution theorem forG-monotone functions by weakening the symmetry condition ofG-monotone functions. Our inequalities are described in terms of several orderings obtained from a cone. It is noteworthy that the orderings detect differences in directions. A special case of the orderings induces a majorization-like relation on spheres. Applying our inequality, Bartholomew's conjectures, which concern directions yielding the maximum power and the minimum power of likelihood ratio tests for order-restricted alternatives, are partly settled.  相似文献   
109.
The high temperature reaction of C60 with silver(I) trifluoroacetate followed by 500 °C sublimation and subsequent HPLC purification has led to the isolation of the five trifluoromethyl[60]fullerenes C60(CF3)n (n=2, 4, 6, 8, 10). Four of them have >90% compositional purity. Two of the compounds, C60(CF3)4 and C60(CF3)6, were obtained as C1-symmetry isomers with >90% isomeric purity, and a sample of C60(CF3)2 also contained ca. 15-20% of a Cs-symmetry isomer of C60(CF3)4. The new compounds were characterized by IR and EI mass spectrometry (all five compounds), View the MathML source" title="View the MathML source" src="http://ars.els-cdn.com/content/image/1-s2.0-S0022113903001738-si4.gif"> NMR spectroscopy (C60(CF3)2, C60(CF3)4, and C60(CF3)6), and 2D COSY View the MathML source" title="View the MathML source" src="http://ars.els-cdn.com/content/image/1-s2.0-S0022113903001738-si5.gif"> NMR spectroscopy (C60(CF3)4 and C60(CF3)6). Calculations at the AM1 and DFT levels of theory have led to the prediction of the most likely structures for C60(CF3)2, C1-C60(CF3)4, Cs-C60(CF3)4, and the two most likely structures of C1-C60(CF3)6.  相似文献   
110.
A new series of six 3-aryl-5-hydroxy-5-trifluoromethyl-4,5-dihydro-1H-1-picolinoylpyrazole hydrochlorides were synthesised in one-step in high yields by the reaction of β-methoxyvinyl trifluoromethyl ketones with 2-pyridinecarboxamidrazone in the presence of hydrochloric acid. The hydrochloride salts were easily converted to the respective new series of free trifluoromethylated 4,5-dihydro-1H-1-picolinoylpyrazoles using triethylamine in anhydrous diethyl ether. X-ray structure and View the MathML source" title="View the MathML source" src="http://ars.els-cdn.com/content/image/1-s2.0-S0022113903000575-si47.gif"> NMR data from the pyrazole hydrochlorides are reported.  相似文献   
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