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51.
集成光学Mach—Zehnder型模数转换器 总被引:2,自引:0,他引:2
简述了M-Z干涉调制器型A/D转换器的原理,报道了实验样品的设计参数、制备工艺和实验现象观察,介绍了性能测试的方法和结果. 相似文献
52.
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In this paper, the authors consider the range of a certain class of ASH algebras in [An, Q., Elliott, G. A., Li, Z. and Liu, Z., The classification of certain ASH C*-algebras of real rank zero, J. Topol. Anal., 14(1), 2022, 183–202], which is under the scheme of the Elliott program in the setting of real rank zero C*-algebras. As a reduction theorem, they prove that all these ASH algebras are still the AD algebras studied in [Dadarlat, M. and Loring, T. A., Classifying C*-algebras via ordered, m... 相似文献
55.
Friction plays a key role in the efficiency and stability of the slip-controlled torque converter clutches. The effects of
friction on the dynamics and stability of a slip-controlled torque converter clutch system using a bifurcation-analysis-based
approach is presented in this paper. A three degree-of-freedom nonlinear driveline model with integral feedback action to
control the clutch slip speed has been utilized for this study. The clutch interface friction is dependent on the slip speed
and is a function of the static friction constant, μ
0, the low velocity friction constant μ
1, and the low velocity exponential rate, γ. Using one-parameter numerical continuation, local Hopf bifurcations of the subcritical type are observed as the friction
parameters μ
1 and γ were varied at low slip speeds. The continuation results are verified using simulations of the full nonlinear model. Stick-slip
and undesirable oscillations of the model inertia elements are observed for certain parameter values. As the slip speed is
increased, the bifurcation instability occurs at an increasingly higher value of μ
1 signifying an improved tolerance of negative friction gradient at higher slip speeds. Smaller exponential rates γ are tolerated at higher slip speeds before the bifurcation instability occurs. For the range of parameter values considered,
no bifurcations occur for a slip speeds higher than 3.4 and 4.5 rad/s with μ
1 and γ as the continuation parameters, respectively. These values of slip speeds are much lower than the system’s first mode of
torsional vibration of 16 Hz (≈100 rad/s). 相似文献
56.
M. Gavelle G. Sarrabayrouse E. Scheid S. Siskos M. Fragopoulou M. Zamani 《Radiation Physics and Chemistry》2011,80(12):1437-1440
A MOSFET-based low-energy neutron dosimeter has been fabricated using a 10B loaded gate electrode as (n,α) converter. The response to thermal neutrons has been studied. 相似文献
57.
Acid/base mobile phase modifiers affect enantioseparations in ways that are not yet understood for the lack of systematic studies, which makes the scale-up of preparative separations difficult to predict. Shifts of the selectivity of certain pairs of enantiomers upon exposure of the column to these modifiers is amply documented. Furthermore, once the modifier has been removed from the mobile phase, the improved selectivity remains, this phenomenon has been named the memory effect. We selected four enantiomeric pairs for a systematic study of this memory effect. The selectivity of 4-chlorophenylalanine ethyl ester (4CPEE) improves after a solution of ethanesulfonic acid (ESA) is percolated through the column. The selectivity of propranolol HCl and Tröger's base increases after a solution of diiospropylethylamine is percolated through the column. The selectivity of these three pairs of enantiomers is inversely affected by percolation of the opposite acid/base solution. Each of these four compounds reached an equilibrium concentration that maintained the separation of the enantiomeric pairs. In contrast, the selectivity of trans-stilbene oxide (TSO) is not affected by either acid/base modifier. Preparative separations can be used to detect changes in the active surface of the chiral polymer stationary phase by measuring the change in selectivity and resolution when modifiers are used. Preparative method development was carried out on analytical columns and scale-up to 1 cm ID columns were performed in this study. 相似文献
58.
从模式保留和转换的角度, 过模波导器件可分为模式转换器、模式保留器和模式综合器. 传统方法只解决其中一种器件的设计或者对器件的某个指标进行改进. 本文在深入分析耦合波理论之后, 提出了过模波导器件的迭代设计方法, 从原理上解决了过模波导器件的设计问题. 该方法能够统一设计三类过模波导器件, 通过添加不同的结构控制方法, 可得到转换效率更高、带宽更宽、结构更紧凑、满足不同工程需求的器件, 而且还能有效设计一些新型器件. 给出了两个设计实例: 双频TM01–TE11模式变换器和光壁馈源喇叭. 双频TM01–TE11模式变换器的两个工作频点为8.75 GHz和10.3 GHz, 波导半径为16 mm, 在两个频点转换效率为99%以上. 光壁馈源喇叭实现TE11模式向高斯束的转换. CST仿真结果验证了这两个器件设计的正确性和有效性.
关键词:
耦合波理论
模式转换器
模式过渡器
迭代法 相似文献
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对ICF实验中条纹相机的重要组件变像管的工作过程进行了介绍,建立了其内部电子光学系统模型,对其静态电子光学特性进行了数值模拟。模拟软件采用ANSYS,数值计算基于有限元数值计算方法,并利用哈密顿原理求解泛函,在控制计算精度的基础上,得出了该电子光学系统的内部静电场分布和轴上电位分布,同时对静态条件下的电子轨迹进行了模拟计算。结果显示了与理论解析结果很好的相似性,同时初步探索了电极尺寸及电压参数对成像的影响。结果表明,电压参数的改变对光电子成像的影响要更大一些。 相似文献