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51.
The anisotropic diffusion is an efficient smoothing process. It is widely used in noise removing and edges preserving via different schemes. In this paper based on a mathematical background and the existing efficient anisotropic function in the literature we developed a new mathematical anisotropic diffusion function which is able to overcome the drawbacks of the traditional process such as the details loss and the image blur. The simulations results and the comparative study with other recent techniques are conducted and showed that the proposed schema generates a wide improvement in the quality of the restored images. This improvement has been shown subjectively in terms of visual quality, and objectively with reference to the computation of some criteria. The simulated images are well de-noised but the most important is that details and structural information are kept intact. In addition to that, the proposed new function was found very interesting and presents numerous advantages like its similarity to the conventional model and the importance of the speed hence it converges faster which allows an opportunity to be well implemented in our de-noising process.  相似文献   
52.
The flow of an oil–water two-phase fluid in an inclined pipe exhibits fundamentally different behaviors to that of a vertical two-phase flow, especially the flow commonly presents complex countercurrent flow structure due to the influence of gravity. The understanding of inclined oil–water flow is of important significance for flow measurement and production optimization. We using multi-scale cross entropy (MSCE) analysis investigate the nonlinear dynamics of inclined water-dominated oil–water two-phase flow patterns which are Dispersion oil-in-water-Pseudoslugs (D O/W PS), Dispersion oil-in-water-Countercurrent (D O/W CT) and Transitional Flow (TF). We find that the rate of low-scale cross entropy can effectively identify flow patterns, and the high-scale cross entropy can represent their long-range dynamics. The research results show that the multi-scale cross entropy analysis can be a helpful tool for revealing nonlinear dynamics of inclined oil–water two-phase flow in terms of microscopic and macroscopic views.  相似文献   
53.
Planar carbon-based electronic devices, including metal/semiconductor junctions, transistors and interconnects, can now be formed from patterned sheets of graphene. Most simulations of charge transport within graphene-based electronic devices assume an energy band structure based on a nearest-neighbour tight binding analysis. In this paper, the energy band structure and conductance of graphene nanoribbons and metal/semiconductor junctions are obtained using a third nearest-neighbour tight binding analysis in conjunction with an efficient nonequilibrium Green's function formalism. We find significant differences in both the energy band structure and conductance obtained with the two approximations.  相似文献   
54.
《Ceramics International》2023,49(1):425-430
In this work, we study TiN/SiOx/ITO devices to implement conductance quantization and multilevel conductance for high-density memory applications. We observed stepwise conductance with integer and half-integer multiples under pulse and DC voltages. We predict this device's conductance quantization to be a combined result of the formation and rupture of oxygen vacancies in SiOx film and the formation of O2?rich ITO layers due to the oxidation reaction between ITO and SiOx. Furthermore, it was found that TiN/SiOx/ITO RRAM devices could stably endure each conductance level.  相似文献   
55.
This article describes a new electrical conductance converter method suitable for low power applications and an implementation in standard CMOS technology. Despite being designed to meet specific measurements requirements, this converter is intended for applications where device power requirements are determinative such self powered sensors networks and implantable devices. The topology is described and an implementation is presented. Results show the possibility of being powered by a single 1.2 V accumulator cell with a consumption of 8 nJ per conversion.  相似文献   
56.
电导式相关流量计应用于油井井下流量测量   总被引:5,自引:0,他引:5  
本文提出了一种新型的电导相关流量计,其敏感元件采用两个电导传感器,该流量能够应用于高含水油井的油水两相流流量测量,在多相流动实验装置上进行的实验表明,该流量计测量的流速范围宽,线性好,该流量计已经在大庆油田进行现场试验,使用该流量计在井下测量的油水的总流量与地面计量结果对比良好。  相似文献   
57.
聚酰亚胺(Polyimide,PI)膜是一种新型的有机膜,具有耐高温、耐强酸和耐辐射等特性,用其制备的重离子微孔膜可以用于电池隔膜和放射性废气过滤等特殊领域。应用中国原子能科学研究院HI-13串列加速器产生的重离子束32S离子轰击25?m的PI薄膜,再对薄膜进行化学蚀刻处理,使由重离子辐照损伤产生的径迹形成微孔。为改善微孔质量,在化学蚀刻前采用具有强氧化性溶液对PI膜进行预处理浸泡,系统分析了常温下采用高锰酸钾和双氧水两种溶液浸泡不同时间对PI膜化学蚀刻的影响。实验结果显示,预处理浸泡可明显加快PI膜的径迹蚀刻速率,缩短蚀刻时间,减小微孔的锥角和提高PI重离子微孔膜的蚀刻质量。  相似文献   
58.
双极型晶体管在受到中子辐照之后,要引起电流增益和饱和压降的退化。本文主要分析:1.不同纵向参数的器件,电流增益在各个区域的退化程度,且与测试h_(FE)时的电流密度及h_(FEo)的关系;2.影响饱和压降变化的各种因素,结果表明电导调制宽度X_c的减小是引起饱和压降退化的主要原因;3.利用加固器件的辐照结果对寿命损伤常数K值进行了推算,由于K是杂质浓度的函数,不同区域K值不同。  相似文献   
59.
Based on first principles, theoretical studies of atomic-scale platinum contacts are presented. A short monatomic wire freely suspended between tips is seen to vibrate as its tensile load increases. The main vibration mode is transversal for lower tensions and longitudinal for higher tensions up to the breaking of the nanowire. The computed conductance exhibits oscillation in the sub-picosecond regime that can be well correlated to the mechanical oscillations of the nanowire. Both the values for the maximum tensile load and the average conductance agree well with available experimental measurements.  相似文献   
60.
介绍导电spacer的性能、结构、可靠性判断、检测方法、使用选取方法等。  相似文献   
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