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着眼于企业高管团队战略协同系统所蕴含的学术与实践价值,研究系统效能重于高管团队自身的作为,关注系统优化则更重于传统模式下高管团队的内部建设.本文首先探究了高管团队与企业战略的协同机理;然后将基于实码加速遗传算法的投影寻踪分类模型技术引入子系统及子系统序参量的权重计算和有序度评价,提出了新的协同度评价方法,建立了高管团队的战略协同度评价模型;应用该模型对S企业进行了实例研究,印证了模型的可操作性.企业高管团队的战略协同度评价结果有助于识别具体企业高管团队战略协同进程中的制约要素,从而有针对性地提出优化对策. 相似文献
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First-principles study of the influences of oxygen defects upon the electronic properties of Nb-doped TiO_2 by GGA + U methods 下载免费PDF全文
The influence of oxygen defects upon the electronic properties of Nb-doped TiO2has been studied by using the general gradient approximation(GGA)+U method. Four independent models(i.e., an undoped anatase cell, an anatase cell with a Nb dopant at Ti site(NbTi), an anatase cell with a Nb-dopant and an oxygen vacancy(NbTi+VO), and an anatase cell with a Nb-dopant and an interstitial oxygen(NbTi+Oi)) were considered. The density of states, effective mass, Bader charge, charge density, and electron localization function were calculated. The results show that in the NbTi+VOcell both eg and t2glevels of Ti 3d orbits make contributions to the electronic conductivity, and the oxygen vacancies(VO) collaborate with Nb-dopants to favor the high electrical conductivity by inducing the Nb-dopants to release more excess charges. In NbTi+Oi, an unoccupied impurity level appears in the band gap, which served as an acceptor level and suppressed the electronic conductivity. The results qualitatively coincide with experimental results and possibly provide insights into the preparation of TCOs with desirable conductivity. 相似文献
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采用基于密度泛函理论第一性原理GGA和GGA+U相结合的方法研究了不同掺杂浓度下锐钛矿相和金红石相Nb:TiO2的晶体结构、电子结构以及稳定性.结果表明:锐钛矿相Nb:TiO2能带结构与简并半导体类似,呈类金属导电机理.金红石相Nb:TiO2呈半导体导电机理.Nb原子比Ti原子电离产生出更多的电子.锐钛矿相Nb:TiO2中Nb原子的电离率比金红石相Nb:TiO2的大.以上结果说明锐钛矿相Nb:TiO2比金红石相Nb:TiO2更适宜用作TCO材料;掺杂浓度对其杂质能级,费米能级和有效质量都有影响.Nb原子掺杂浓度越高,材料电离率呈降低趋势;形成能计算结果显示:在富钛条件下不利于Nb原子的掺杂,而在富氧条件下有利于Nb原子的掺杂.对于金红石相和锐钛矿相Nb:TiO2,不论是在贫氧或富氧条件下,随着Nb原子掺杂浓度的提高,形成能均增大. 相似文献
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High-Pressure Water-Vapor Annealing for Enhancement of a-Si:H Film Passivation of Silicon Surface 下载免费PDF全文
We investigate the effect of amorphous hydrogenated silicon (a-Si:H) films passivated on silicon surfaces based on high-pressure water-vapor annealing (HWA). The effective carrier lifetime of samples reaches the maximum value after 210℃, 90min HWA. Capacitance-voltage measurement reveals that the HWA not only greatly reduces the density of interface states (Dit), but also decreases the fixed charges (Qfixed) mainly caused by bulk defects. The change of hydrogen and oxygen in the film is measured by a spectroscopic elHpsometer and a Fourier-transform infrared (FTIR) spectrometer. All these results show that HWA is a useful method to improve the passivation effect of a-Si:H films deposited on silicon surfaces. 相似文献
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