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排序方式: 共有205条查询结果,搜索用时 15 毫秒
1.
D. Solís-Cortés E. Navarrete-Astorga J.L. Costa-Krämer J. Salguero-Fernandez R. Schrebler D. Leinen E.A. Dalchiele J.R. Ramos-Barrado F. Martín 《Ceramics International》2019,45(5):5577-5587
C-axis textured thin films of gallium-doped indium zinc oxide (GIZO) with a 2% ratio of Ga/Zn, were obtained via RF-magnetron sputtering with high transparency and electrical conductivity. A Box-Behnken response surface design was used to evaluate the effects of the deposition parameters (In2O3 target power, deposition time, and substrate temperature) on the chemical composition, optical, electrical, and structural properties of the GIZO films. The optical constants and the electrical properties were obtained using optical models. The GIZO stoichiometry, and therefore the In/Zn atomic ratio, affected the crystallinity, crystalline parameters, band gap, and charge carrier mobility of the GIZO films. The charge carrier density was related to the change in the crystalline parameters of the hexagonal structure and the In/Zn atomic ratio. The best electrical conductivity values (1.75?×?103 Ω?1 cm?1) were obtained for GIZO films with In/Zn ratio ≥?1. Several figures of merit (FOM) defined for the visible and solar regions were comparatively used to select the optimal In/Zn atomic ratio that provided the best balance between the conductivity and the transparency. The optimal In/Zn ratio was in a range of 0.85–0.90 for the GIZO films. 相似文献
2.
将晶体管设计中繁琐的纵向、横向参数的设计计算以及参数验算,采用Basic人机对话方式,由计算机完成。并用BAsic语言绘制出所需的七块光刻掩膜图。既大大地减轻了设计人员繁琐劳动、缩短了设计时间、提高设计质量,又便于修改。还可广泛用于同种结构的不同动率要求的各种晶体管的设计中。 相似文献
3.
Al,Ga取代Bi:DyIG薄膜的磁和磁光特性的研究 总被引:1,自引:0,他引:1
本文报道用热分解法在玻璃衬底上制备了Al和Ga取代的Bi:DYIG薄膜,对其磁和磁光特性做了详细研究.Al和Ga取代的薄膜均可获得好的矩形比和高的矫顽力.对于Bi1.2Dy1.8Fe5-xMXO12(M=A1,GZ)薄膜,A1和G2的最佳替代成份分别为1.0和G.7;最佳晶化温度分别为700o℃和675℃.在波长510nm附近,法拉第旋转角可达8°/um左右.光学吸收和品质因子的研究结果表明,Al和Ga取代能够影响光学吸收和品质因子,其中Ga取代对光学吸收和品质因子的影响较大. 相似文献
4.
间歇窑窑墙温度场图形仿真研究 总被引:2,自引:0,他引:2
本文利用有限差分法求解间歇窑窑墙中的温度分布,并用C语言设计了窑墙温度场图形仿真软件。输入窑墙厚度和材料的物性参数等,系统可进行窑墙温度场分布的实时仿真及窑炉结构与操作的优化 相似文献
5.
A figure of merit (FOM) has been developed to define the quality of ceramic (e.g., ZrO2) coatings on metal and alloy [Type 304SS and Alloy 600] surfaces. Zirconia (ZrO2) coatings were developed as a means of protecting the metal/alloy surfaces from stress corrosion cracking (SCC) in boiling water reactor (BWR) primary heat transport circuits, by inhibiting the cathodic reaction (reduction of oxygen and hydrogen peroxide) on the surface external to the crack. The distribution of pores in the coating plays an important role in corrosion prevention, such that the lower the porosity of the coating, the better the protection afforded to the system against SCC. Since the reactors operate at high temperature (e.g., at 288 °C under full power conditions), the temperature dependence of the FOM was investigated. The figure of merit (FOM) was developed by measuring impedance data over a wide range of frequency (10 mHz-5 kHz) at temperatures of 25, 100, 200, and 288 °C in hydrogenated, buffered solutions, with the hydrogen electrode reaction (HER) being used as a “fast” redox couple. An “equivalent circuit” analog was first developed from the bare surface impedance data and this analog was then employed in a second step to model the pore bottom in defining the pore distribution on the coated surface. A lognormal distribution (LND) of the pores was assumed and the parameters of the LND were determined using a constrained optimization technique to fit the model to the experimental data for the coated surface at different temperatures. The results suggest that, as temperature increases, the coating becomes more porous, making the substrate more susceptible to corrosion cracking. At 288 °C, 87% of the SS and 85% of the Ni-alloy surfaces become porous with the pore radius varying from 0.0001 cm to 0.01 cm. 相似文献
7.
Xiaonan Lu Saurabh Kataria William J. Brouwer James Z. Wang Prasenjit Mitra C. Lee Giles 《International Journal on Document Analysis and Recognition》2009,12(2):65-81
Authors use images to present a wide variety of important information in documents. For example, two-dimensional (2-D) plots
display important data in scientific publications. Often, end-users seek to extract this data and convert it into a machine-processible
form so that the data can be analyzed automatically or compared with other existing data. Existing document data extraction
tools are semi-automatic and require users to provide metadata and interactively extract the data. In this paper, we describe
a system that extracts data from documents fully automatically, completely eliminating the need for human intervention. The
system uses a supervised learning-based algorithm to classify figures in digital documents into five classes: photographs,
2-D plots, 3-D plots, diagrams, and others. Then, an integrated algorithm is used to extract numerical data from data points
and lines in the 2-D plot images along with the axes and their labels, the data symbols in the figure’s legend and their associated
labels. We demonstrate that the proposed system and its component algorithms are effective via an empirical evaluation. Our
data extraction system has the potential to be a vital component in high volume digital libraries. 相似文献
8.
大型分布式城市监控系统的分析和设计 总被引:2,自引:0,他引:2
从通信线路、系统设备和软件等方面介绍了一种集治安、交通监控和报警等功能于一体的大型分布式城市监控系统的设计思想、系统组成结构和设计方案,阐述了各种设备在系统中的主要作用,通过对子系统中各种数据流的分析,说明了各软件模块的主要功能以及它们之间的联系。 相似文献
9.
The present work presents teaching–learning based optimization (TLBO) algorithm as an optimization technique in the area of tuning of the classical controller installed in automatic voltage regulator (AVR). The proposed TLBO algorithm is applied with an aim to find out the optimum value of proportional integral derivative (PID) controller gains with first order low pass filter installed in the AVR. The voltage response of the AVR system, as obtained by using the proposed TLBO based PID controller with first order low pass filter, is compared to those offered by the other algorithms reported in the recent state-of-the-art literatures. The advantage of using this control strategy may be noted by providing good dynamic responses over a wide range of system parametric variations. For on-line, off-nominal operating conditions, fast acting Sugeno fuzzy logic technique is applied to obtain the on-line dynamic responses of the studied model. Furthermore, robustness analysis is also carried out to check the performance of the designed TLBO based PID controller. An analysis, based on voltage response profile, has been investigated with the variations of the model parameters. The simulation results show that the proposed TLBO based PID controller is a significant optimization tool in the subject area of the AVR system. The essence of the present work signifies that the proposed TLBO technique maybe, successfully, applied for the AVR of power system. 相似文献
10.
由于各种因素的影响,地形图会发生不规则变形,因此,必须对其进行纠正.为此提出了一种射影变换纠正法,叙述了其纠正方法和纠正原理,并总结了其优点. 相似文献