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排序方式： 共有2137条查询结果，搜索用时 15 毫秒
101.
利用有限元方法研究一类广泛的非线性广义神经传播方程.首先,讨论其在半离散格式下解的收敛性;其次,利用插值算子与Ritz-Volterra投影相一致的特殊性质得到了解的超逼近性质;最后,通过构造一个插值后处理算子导出了解的整体超收敛结果. 相似文献
102.
运用密度泛函理论,计算了Sbzn、Nazn、Sbzn-nNazn掺杂ZnO晶体的稳定性、能带结构和电子态密度.研究发现Sbzn、Nazn、Sbzn-nNazn掺杂ZnO晶体的结构稳定,Sb-Na共掺杂改善了体系的固溶度.能带结构表明,SbZn体系为n型间接带隙半导体材料;NaZn、Sbzn-2NaZn体系为p型半导体材料;Sbzn-NaZn、SbZn-3NaZn体系为本征半导体材料.对p型半导体材料体系的导电性能研究发现,Sbzn-2Nazn体系电导率大于NaZn体系的电导率,即Sbzn-2NaZn掺杂改善了体系的导电性.计算结果为实验制备p型ZnO材料提供了理论指导. 相似文献
103.
Simon Eberle 《ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik》2016,96(10):1205-1219
In this paper we give an explicit formula for the homogenization limit of Poisson's equation for a wide range of non‐periodic problems including self‐similarly ramified domains. This work was motivated by the modelling of the diffusion of medical sprays in lungs, which can be approximated by a self‐similarly ramified domain. Such motivation also led us to consider the influence that a continuous scaling of the size of holes towards a chosen direction (e.g. towards the fractal boundary) has on the homogenization limit. It turned out that our strategy to explicitly calculate a formula for the homogenization limit could be applied beyond self‐similar perforations as presented in this article. 相似文献
104.
In this study,the high performance of InGaN/GaN multiple quantum well light-emitting diodes(LEDs) with Aldoped ZnO(AZO) transparent conductive layers(TCLs) has been demonstrated.The AZO-TCLs were fabricated on the n~+-InGaN contact layer by metal organic chemical vapor deposition(MOCVD) using H_2O as an oxidizer at temperatures as low as 400 ℃ without any post-deposition annealing.It shows a high transparency(98%),low resistivity(510 ~4 Ω·cm),and an epitaxial-like excellent interface on p-GaN with an n+-InGaN contact layer.A forward voltage of 2.82 V @ 20 mA was obtained.Most importantly,the power efficiencies can be markedly improved by 53.8%@20 mA current injection and 39.6%@350 mA current injection compared with conventional LEDs with indium tin oxide TCL(LED-Ⅲ),and by28.8%@20 mA current injection and 4.92%@350 mA current injection compared with LEDs with AZO-TCL prepared by MOCVD using O_2 as an oxidizer(LED-Ⅱ),respectively.The results indicate that the AZO-TCL grown by MOCVD using H_2O as an oxidizer is a promising TCL for a low-cost and high-efficiency GaN-based LED application. 相似文献
105.
In this study, the unipolar resistive switching(URS) and bipolar resistive switching(BRS) are demonstrated to be coexistent in the Ag/Zn O/Pt memory device, and both modes are observed to strongly depend on the polarity of forming voltage. The mechanisms of the URS and BRS behaviors could be attributed to the electric-field-induced migration of oxygen vacancies(VO) and metal-Ag conducting filaments(CFs) respectively, which are confirmed by investigating the temperature dependences of low resistance states in both modes. Furthermore, we compare the resistive switching(RS)characteristics(e.g., forming and switching voltages, reset current and resistance states) between these two modes based on VO- and Ag-CFs. The BRS mode shows better switching uniformity and lower power than the URS mode. Both of these modes exhibit good RS performances, including good retention, reliable cycling and high-speed switching. The result indicates that the coexistence of URS and BRS behaviors in a single device has great potential applications in future nonvolatile multi-level memory. 相似文献
106.
Alexander Chizhik Andrzej Stupakiewicz Arcady Zhukov Julian Gonzalez 《physica status solidi (a)》2016,213(2):350-355
107.
Joo Resende Carmen Jimnez Ngoc Duy Nguyen Jean‐Luc Deschanvres 《physica status solidi (a)》2016,213(9):2296-2302
108.
Rajaraman Ramakrishnan K. B. Jinesh Sudha J. Devaki Manoj Raama Varma 《physica status solidi (a)》2016,213(9):2414-2424
109.
110.
Yuan Xu; 《Studies in Applied Mathematics》2024,153(2):e12703
We study orthogonal polynomials (OPs) for a weight function defined over a domain of revolution, where the domain is formed from rotating a two-dimensional region and goes beyond the quadratic domains. Explicit constructions of orthogonal bases are provided for weight functions on a number of domains. Particular attention is paid to the setting when an orthogonal basis can be constructed explicitly in terms of known polynomials of either one or two variables. Several new families of OPs are derived, including a few families that are eigenfunctions of a spectral operator and their reproducing kernels satisfy an addition formula. 相似文献