白宣羽
,
汪渊
,
徐可为
稀有金属材料与工程
采用磁控溅射方法在Si(111)基片上沉积Cu-Zr/ZrN薄膜体系作为扩散阻挡层.通过比较Cu-Zr/ZrN薄膜体系和三元非晶(Mo,Ta,W)-Si-N的电阻率,同时比较Cu-Zr/ZrN薄膜体系和Ta,YaN的硬度,说明作为扩散阻挡层的材料的选取,应从整体性能上考虑,而不能仅仅考虑热稳定性等单一指标.
关键词:
非晶
,
电阻率
,
纳米压入
,
硬度
Journal of Materials Research
Based on the best bulk metallic glass (BMG) forming alloy in the Mg-Cu-Y ternary system, we introduced Ag (or Ni) to partially substitute for Cu to improve the glass-forming ability (GFA). The objective of this paper is twofold. First, we illustrate in detail a recently developed search strategy, which was proposed but only briefly outlined in our previous publication [H. Ma, L.L. Shi, J. Xu, Y. Li, and E. Ma: Discovering inch-diameter metallic glasses in three-dimensional composition space. Appl. Phys. Lett. 87, 181915 (2005)]. The protocol to navigate in three-dimensional composition space to land large BMGs is spelled out step-by-step using the pseudo-ternary Mg-(Cu,Ag)-Y as the model system. Second, our ability to locate the best BMG former in the composition tetrahedron allows us to systematically examine, and conclude on, the effects of a given alloying element. The large improvement in glass-forming ability in the Mg-(Cu,Ag)-Y system relative to the based ternary will be contrasted with the reduced glass-forming ability in the Mg-(Cu,Ni)-Y pseudo ternary system. It is demonstrated that the improvement of glass-forming ability requires judicious choice of substitutional alloying elements and concentrations, rather than simple additions of multiple elements assuming the "confusion principle."
关键词:
bulk metallic-glass;shaped copper mold;amorphous-alloys;thermal-stability;ternary-system;casting method;p system;diameter;zr;mm
孙保基
,
张葆
,
宋策
,
龙思源
液晶与显示
doi:10.3788/YJYXS20163109.0921
针对TLD算法的特征点无法有效表述目标问题,提出了一种基于角点增强改进的TLD目标跟踪算法。改进算法在跟踪模块加入了对目标表述能力更强,具有光照不敏感性和旋转不变性的 Shi-Tomas 角点作为跟踪特征点。跟踪器运行时,在角点经光流法跟踪和双向误差检测后,利用剩余的稳定角点定位目标窗口。对照结果表明,改进算法在面对目标抖动和形变时可以稳定跟踪;有效抑制因跟踪平滑点造成的漂移现象;提高了跟踪的稳定性。针对 TLD算法跟踪过程中因在线模板积累造成的计算量持续增大、实时性持续降低的问题,提出了一种依据相似度中值的模板判断删除机制。该删除机制在模板积累到设定阈值时运行,根据模板与当前目标的相似度,删除不再具备代表性的模板;调整模板空间并更新模板数目。实验表明,该删除机制在应对模板更新快、持续时间长的跟踪情景时有效降低算法计算量,实时性可提高约20%。
关键词:
目标跟踪
,
TLD
,
角点特征
,
在线模板