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21.
直接斜率波前复原算法的控制效果分析 总被引:7,自引:0,他引:7
建立自适应光学系统功率谱抑制函数的概念,分析了采用直接斜率波前复原算法的自适应当光学系统的控制效果,理论分析与61单元自适应光学系统上的实验结果表明,直接斜率波前复原算法将导致控制效果下降。 相似文献
22.
The microstructural evolution during the hot rolling of coarse grain sized austenite has been modeled considering all the microstructural mechanisms (dynamic, static and metadynamic recrystallization, strain induced precipitation) that can take place during an industrial TSDR production of three Nb microalloyed steels. Based on the results obtained from the model, processing maps have been drawn for 0.02%, 0.035% and 0.05% Nb microalloyed steels. Optimum processing conditions to exploit all the benefits of the Nb microalloying have been defined considering a final gauge thickness range between 1.5 and 12.65 mm. In addition, and facing the difficulties present in the production of thick hot strip, several alternative thermomechanical schedules are proposed, which would originate microstructures with a suitable combination of homogeneity and retained strain prior to transformation. 相似文献
23.
A three-dimensional (3D), two-phase, isothermal model of direct methanol fuel cells (DMFCs) was employed to investigate effects of electron transport through the backing layer and the land in bipolar plates. It was found that the electronic resistance of the backing layer, affected by backing layer electronic conductivity, backing layer thickness and flow channel width, played a relatively important role in determining the current density distribution and cell performance. In order to ignore the electron transport effect on the average current density, the minimum electronic conductivity of the backing layer has to be 1000 S m−1, with the relative error in the average current density less than 5%, under the given conditions. 相似文献
24.
Ray-cast volume rendering accelerated by incremental trilinear interpolation and cell templates 总被引:3,自引:0,他引:3
Two related ideas for improving the speed of ray-cast volume rendering are studied in this paper. The first is an incremental algorithm for trilinear interpolation, a method commonly used in ray-cast volume rendering to calculate sample values. The incremental algorithm can expedite trilinear interpolation when many samples along a ray are located in one cell. The second is an efficient hybrid volume rendering restricted to parallel projection. In the preprocessing stage, acell template is created to store the information used by the incremental trilinear interpolation. When a cell is parallel projected, the information is retrieved from the template to compute the cell contribution. Because the algorithm with only one template may cause aliasing, an antialiasing technique exploiting multiple cell templates is proposed. With our method, ray-cast volume rendering can be accelerated considerably. 相似文献
25.
张先洪 《电脑编程技巧与维护》2012,(10):94-96
利用Visual C++和Direct3D对某雷达显示器的实现过程作了详细论述,包括数据采集、PPI型显示器、A型显示器、B型显示器、余晖显示、航迹显示等。通过试验证明,采用Direct3D绘图方式比采用GDI绘图方式效果好,更适用于数据处理量大、天线扫描速度快的雷达显示器。 相似文献
26.
Tianqi ZhangAuthor Vitae Shaosheng DaiAuthor VitaeWei ZhangAuthor Vitae Guoning MaAuthor VitaeXiangyun GaoAuthor Vitae 《Digital Signal Processing》2012,22(1):106-113
This paper presents a method of singular value decomposition (SVD) plus digital phase lock loop (DPLL) to solve the difficult problem of blind pseudo-noise (PN) sequence estimation in low signal to noise ratios (SNR) direct sequence spread spectrum (DS-SS, DS) signals with residual carrier. Of course, the method needs to know the parameters of DS signal, such as the period and code rate of PN sequence. Firstly, the received signal is sampled and divided into non-overlapping signal vectors according to a temporal window, whose duration is two periods of PN sequence. Then, an autocorrelation matrix is computed and accumulated by the signal vectors one by one. The PN sequence with residual carrier can be estimated by the principal eigenvector of this autocorrelation matrix. Furthermore, a DPLL is used to deal with the estimated PN sequence with residual carrier, it estimates and tracks the residual carrier, removes the residual carrier in the end. Theory analysis and computer simulation results show that this method can effectively realize the PN sequence estimation from the input DS signals with residual carrier in lower SNR. 相似文献
27.
论述了导致非高炉炼铁技术发展的原因,简介了90年代蓬勃兴起的,各种有发展前途的直接还原技术和熔融还原技术,本部分主要介绍Arex,Iron Carbide,Fastmet等直接还原技术及其优缺点。 相似文献
28.
《The Electricity Journal》2021,34(7):107000
Carbon capture utilization and storage is an important technology option to rapidly and profoundly decarbonize the power sector, but will not deploy without substantial incentives or regulation. Assessment of U.S. policy options reveals that current incentives only partially close the finance gap and are most sensitive to fuel type and ownership structure. Recent proposed legislation would in some designs attract private investment for many projects, leading to widespread deployment of CCUS in the power sector. Additional constraints and concerns (including technology options and presence of CO2 infrastructure) could play an important secondary role. This study discusses the specific US incentive policies that can provide investors and lenders with net cash flows that are adequate to attract private capital to CCUS power projects in the US. 相似文献
29.
《The Electricity Journal》2021,34(7):107002
Environmental justice (EJ) and climate justice are becoming central foci of climate policy. Awareness is also growing on the need for some amount of carbon dioxide removal (CDR) to curb warming to 1.5 °C. In this paper we map dimensions of environmental and climate justice that stakeholders and communities will need to consider -- from local to global scales. Mapping issues is a step towards developing frameworks to undertake CDR in an environmentally just way. 相似文献
30.
Cu-Fe-Cr原位复合材料的纤维相结构 总被引:3,自引:0,他引:3
通过感应熔炼和冷拔变形制备了Cu 16Fe 2Cr原位复合材料 ,将铜基体选择腐蚀后提取出了纤维 ,采用SEM和TEM观察分析了纤维相结构。在较低的应变量 (η =1.6 7)时 ,纤维不均匀 ,随着变形量的增大 (η =5 .42 ) ,纤维外形变得均匀。在 η =5 .42时 ,一个显著的特点是单根Fe Cr纤维分为一些由晶界隔开的平行亚单元 (宽度约为 10 0nm) ,通过亚单元共同的 [110 ]衍射获得了晶粒之间的相对取向 ,相邻晶粒的取向角在 3°~ 15°之间。 相似文献