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结合战时装备保障实际情况和战损装备抢修任务特点,分析了现有战损装备抢修任务指派模型的特点及不足.依据紧急程度对战损装备抢修任务进行分类,建立了不同紧急度对应的装备抢修任务指派模型,重点是利用蚁群算法对模型进行求解.最后通过某装备保障想定的实例进行了验证,结果表明该算法操作简单、切实有效,能有效实施战损装备应急抢修任务的指派,在装备保障智能决策系统中有较好的应用前景.  相似文献   
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The method of numerical simulation is used to fit the relationship between the photoconductivity in films and the illumination time. The generation and process rule of kinds of different charged defect states during illumination are revealed. It is found surprisingly that the initial photoconductivity determines directly the total account of photoconductivity degradation of sample.  相似文献   
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The optical properties of hexagonal boron nitride(h-BN) thin films were studied in this paper.The films were characterized by Fourier transform infrared spectroscopy,UV-visible transmittance and reflection spectra.h-BN thin films with a wide optical band gap Eg(5.86 eV for the as-deposited film and 5.97 eV for the annealed film) approaching h-BN single crystal were successfully prepared by radio frequency(RF) bias magnetron sputtering and post-deposition annealing at 970 K.The optical absorption behaviour of h-BN films accords with the typical optical absorption characteristics of amorphous materials when fitting is made by the Urbach tail model.The annealed film shows satisfactory structure stability.However,high temperature still has a significant effect on the optical absorption properties,refractive index n,and optical conductivity σ of h-BN thin films.The blue-shift of the optical absorption edge and the increase of Eg probably result from stress relaxation in the film under high temperatures.In addition,it is found that the refractive index clearly exhibits different trends in the visible and ultraviolet regions.Previous calculational results of optical conductivity of h-BN films are confirmed in our experimental results.  相似文献   
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立方氮化硼薄膜的光学带隙   总被引:1,自引:0,他引:1       下载免费PDF全文
邓金祥  汪旭洋  姚倩  周涛  张晓康 《物理学报》2008,57(10):6631-6635
用射频溅射法在p型Si(100)衬底上沉积立方氮化硼(c-BN)薄膜,薄膜的成分由傅里叶变换红外谱标识,用紫外-可见分光光度计测量了c-BN薄膜的反射光谱,利用K-K(Kramers-Kroning)关系从反射谱计算出c-BN薄膜的光吸收系数,进而确定c-BN薄膜的光学带隙.对于立方相含量为55.4%的c-BN薄膜,光学带隙为5.38eV. 关键词: 立方氮化硼薄膜 光学带隙 K-K关系  相似文献   
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用磁控溅射法制备六角氮化硼薄膜,在衬底温度、衬底偏压、工作气压等条件一定的情况下改变工作气体(氮气+氩气)中氮气的比例,以制备高质量的六角氮化硼薄膜,薄膜以红外吸收光谱标识。实验结果表明,工作气体中氮气的比例对制得的六角氮化硼薄膜有很大影响,在氮气比例为20%时得到理想的六角氮化硼薄膜。  相似文献   
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