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集值映射向量优化问题的ε-真有效解 总被引:2,自引:0,他引:2
本文讨论集值映射向量优化问题的ε-真有效解。在集值映射为广义锥-次类凸的假设下,建立了这种解的标量化定理,ε-Lagrange乘子定理,ε-真鞍点定理和ε-真对偶性定理。 相似文献
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<正>In situ-satellite match-ups of radiometric data are established in the turbid waters of the Yellow Sea and the East China Sea.Inherent optical properties(IOPs) are retrieved by match-up radiometric data and multi-band quasi-analytical algorithm(QAA).By comparing in situ spectra-retrieved IOPs with the satellite ones of moderate resolution imaging spectroradiometer(MODIS) and medium resolution imaging spectrometer(MERIS),the accuracy of satellite-derived IOPs is quantified.The median of the absolute percentage difference is found to be approximately 20%for the total absorption coefficient a_t(λ) at green and blue-green bands,and 30%for particulate material backscattering coefficient b_(bp)(λ) throughout the visible bands.The spatial pattern and temporal variability of IOPs along the eastern coast of China are clarified based on satellite images and the QAA model. 相似文献
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高能激光广泛应用于材料加工、科学研究、空间碎片清除、军事应用等领域。二极管泵浦高能激光具有结构紧凑,系统简单、全电驱无限弹仓的特点,近年来,各类二极管泵浦高能激光围绕着同时实现高功率、高效率、高光束质量这一总目标发展迅速。详细综述了国内外高平均功率块状固体激光、高功率可见光波段激光、高峰值功率激光、高功率光纤激光、碱金属蒸气激光等二极管泵浦高能激光的研究进展,并对其发展趋势进行了展望。 相似文献
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二极管泵浦全固态589 nm脉冲激光器 总被引:2,自引:1,他引:1
报道了一台二极管激光器(DL)泵浦的全固态Nd:YAG和频激光器,激光是由Nd:YAG晶体的1 064 nm 和1 319 nm 谱线外腔和频产生,以6 mm×6 mm×12 mm KTP为和频晶体,采用Ⅱ类临界相位匹配, 在400 Hz重复频率下,当分别注入3.05 W和2.46 W的1 064 nm和1 319 nm调Q脉冲到KTP晶体时,和频最大输出达到了1.3 W,脉宽为35 ns,线宽优于3 GHz,和频效率达到了23.5%, 光束质量因子分别为1.84和1.93。实验结果表明采用激光二极管阵列泵浦Nd:YAG/ KTP 腔外和频技术是获得黄激光的高效方法, 并通过精确控制谐振腔内标准具的倾角与温度,和频输出波长可精确调谐到Na D2线。 相似文献
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Spatial memory enhances the evacuation efficiency of virtual pedestrians under poor visibility condition
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Spatial memory is a critical navigation support tool for disoriented evacuees during evacuation under adverse environmental conditions such as dark or smoky conditions. Owing to the complexity of memory, it is challenging to understand the effect of spatial memory on pedestrian evacuation quantitatively. In this study, we propose a simple method to quantitatively represent the evacuee's spatial memory about the emergency exit, model the evacuation of pedestrians under the guidance of the spatial memory, and investigate the effect of the evacuee's spatial memory on the evacuation from theoretical and physical perspectives. The result shows that(i) a good memory can significantly assist the evacuation of pedestrians under poor visibility conditions, and the evacuation can always succeed when the degree of the memory exceeds a threshold(? 0.5);(ii) the effect of memory is superior to that of "follow-the-crowd" under the same environmental conditions;(iii)in the case of multiple exits, the difference in the degree of the memory between evacuees has a significant effect(the greater the difference, the faster the evacuation) for the evacuation under poor visibility conditions. Our study provides a new quantitative insight into the effect of spatial memory on crowd evacuation under poor visibility conditions. 相似文献
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基于熵权的可变模糊集方法在水质污染评价中的应用 总被引:1,自引:0,他引:1
水质污染评价是水环境污染防治的重要基础,针对评价过程中评价指标的不确定性,将可变模糊集理论应用于水质污染评价中,首先,建立合理的指标体系与等级标准,然后,将熵值原理引入该方法中,利用指标实测数据的波动性来计算指标权重,最后,利用模糊可变评价模型对水质污染进行组合评价,并将均值作为最终评价结果,将此方法应用于泰州市新通扬运河水质污染评价中,结果表明,与模糊综合评价相比,基于熵权的可变模糊集方法评价结果合理、客观,具有更好的可靠性与稳定性,为水质污染评价工作提供了一种新的研究方法与思路. 相似文献