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交通运输质量综合评价方法的研究 总被引:3,自引:0,他引:3
交通运输业是一个服务特征非常明显的企业,它的生产过程和产品具有一定的特殊性,本根据运输市场规律和生产实际建立了24个指标,以此为基础对运输计划子质量、生产子质量和产品子质量三个子质量进行了定量评价,再以三个子值为基础对运输质量进行了定量综合评价,算例分析表明,该评价方法具有一定的实用价值。 相似文献
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分析了停产后服务备件的三种存储模式,以主要基层仓库和常规基层仓库模式为基本模式,建立了选址库存模型,将两级库存体系不变模式和单级库存体系模式作为特例加以讨论,并设计了基于遗传算法的迭代算法求解选址库存问题,通过仿真算例验证了模型和方法的可行性和有效性.通过分析,主要基层仓库和常规基层仓库模式能够将成本优势与客户服务水平良好结合,是一种较好的模式. 相似文献
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Electron acceleration in a tightly focused ultra-intensity linear polarized laser beam is investigated numerically. It has been found that the acceleration is strong phase dependent and is periodic to the variety of the initial laser field phase. When optimal initial parameters are chosen, the electron can be accelerated effectively. The accelerated electrons are emitted in pulses of which the full width is less than the half period of the laser field. 相似文献
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Micro-lens arrays were adopted to homogenize the beam profile of 532-nm pumping laser for the main amplifier of an intense femtosecond, chirped pulse amplification (CPA) Ti:sapphire laser. Experimental measurements showed a great improvement of the near-field pattern of the CPA beam after the main amplifier and the size of the focal spot was improved from 2.7 times diffraction limitation (DL) to 1.6 DL. The spot size focused by an f/4 off-axis parabola (OAP) in the target chamber was measured to be 5.8μm (full-width at half-maximum (FWHM)), and a peak intensity of 2.6×1020 W/cm2 was obtained at the output power of 120 TW. Peak intensity exceeding 1021 W/cm2 or even 1022 W/cm2 can be expected with smaller f-number focusing configuration and wavefront correction. 相似文献
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应用全反射二阶自相关仪测量超短脉冲脉宽 总被引:6,自引:3,他引:3
计算了普遍采用的二阶单发自相关仪光路中的分束片的色散引起的超短脉冲展宽量,指出在脉冲极短时该展宽将导致不准确的测量结果(例如,对于脉冲宽度为3fs左右,通过100μm厚度的K9玻璃分束片,脉冲展宽将达到10%)。基于计算结果,提出了一种新型的采用全反射结构的单发二阶自相关仪设计,通过分波面的方法改变了自相关仪的分束方式,避免了采用透射分束光学元件引起的色散。采用这种全反射式结构的二阶单发自相关仪,可以使自相关测量方法测得的脉冲宽度更为准确,计算得出理论上其最小时间分辨率可达3.6fs。 相似文献
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