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51.
针对传统的综合满意度模型在研究多响应时较少考虑噪声因素的问题,本文通过引入噪声因素对传统的满意度模型实施改进,进行多响应稳健优化分析。首先,构建包含可控因素和噪声因素的多质量特性的响应曲面模型;其次,借助传统综合满意度模型的构建方法,将多质量特性的响应曲面模型整合为改进的满意度模型;最后,将信噪比作为衡量改进的满意度模型稳健优化的指标,得到稳健优化的参数组合。实证研究表明:构建同时包含可控因素和噪声因素的改进的满意度模型是可行的,在此模型的基础上利用信噪比能够有效地找到多响应稳健优化的参数组合。 相似文献
52.
The transmission properties of a one-dimensional (1D) photonic crystal containing two kinds of single-negative (permittivity or permeability negative) material with an inserted array of defects (RHM and LHM) were presented by the transfer matrix method (TMM). The dependence of the defect modes on the structure parameters was discussed by using the TMM. In contrast to the Bragg gaps, the properties (the central frequency and width of the gap) of zero effective phase (zero−φeff) and gap are invariant with a change in scale length and insensitive to the incident angles. The property of the periodic defect modes in the SNG host periodic structure was studied. It illustrates that the defect modes properties changed more by insert periodic defect than by single-media defect. The defect modes are sensitive to the parameters of the defect layers and the incident angle. 相似文献
53.
54.
For a quasi-Fuchsian group Γ with ordinary set Ω, and Δ
n
the Laplacian on n-differentials on Γ\Ω, we define a notion of a Bers dual basis for ker Δ
n
. We prove that det , is, up to an anomaly computed by Takhtajan and the second author in (Commun. Math Phys 239(1-2):183–240, 2003), the modulus
squared of a holomorphic function F(n), where F(n) is a quasi-Fuchsian analogue of the Selberg zeta function Z(n). This generalizes the D’Hoker–Phong formula det , and is a quasi-Fuchsian counterpart of the result for Schottky groups proved by Takhtajan and the first author in Analysis
16, 1291–1323, 2006.
相似文献
55.
采用Abaqus有限元软件建立新型外包加强型混合节点模型,在验证模型正确性的基础上对其进行拟静力作用下的非线性分析,深入研究各个加载阶段的受力性能及破坏机制,并进行了相关参数对节点抗震性能的影响分析。结果表明,新型节点的最终破坏形态为梁端塑性铰破坏,外包混凝土及扩大包脚的嵌固作用使塑性铰远离节点核心区域,可以有效保护节点核心区和传力路径的连续性;滞回曲线较为饱满,具有较好的耗能能力和塑性变形能力;适当增大扩大包脚立面高度和水平长度,可以提高节点的初始刚度与承载力等性能,并根据相关参数研究给出了合理的设计建议范围,以便为工程设计提供参考。 相似文献
56.
Summary. A new self-oscillating system introducing spontaneous oscillatory phenomena on iron in a sulfuric acid solution of hydrogen
peroxide is discussed. This phenomenon can be explained by a continuous oscillation between the active and passive state of
iron. Unlike other published systems that only show one-peak oscillations, the potential of iron shows highly complex dynamics:
depending on the concentration of hydrogen peroxide and sulfuric acid, a period doubling and non-periodic oscillations in
a self-oscillating system were observed for the first time. The reactions were analyzed by methods based on chaos theory and
could finally be identified as an example of deterministic chaos.
Received April 24, 2001. Accepted May 7, 2001 相似文献
57.
58.
JosM. Isidro 《Journal of Geometry and Physics》1999,29(4):XXLIII-346
The period integrals of non-singular complex algebraic curves in
are shown to satisfy a set of polynomial relations that can be used to formulate the corresponding the Picard-Fuchs equations. Their derivation employs elementary mathematical techniques that have also application in the context of Seiberg-Witten theories. 相似文献
59.
We formulate a renormalization group analysis for the study of the accumulation of period doubling in the presence of noise. The main tool is a renormalization of the time evolution of the noise. The critical indices depend on the nature of the noise, but are given by thermodynamic quantities describing the large deviations of the Lyapunov exponent of the linearized random renormalization. 相似文献
60.
负载型钼基催化剂上甲烷,乙烷无氧芳构化反应研究 总被引:1,自引:0,他引:1
研究了不同载体钼基催化剂上甲烷,乙烷的无氧芳构化反应。在所采用的载体中,HZSM-5具有最佳性能,对甲烷的芳构化反应,Mo/HZSM-5催化剂表现出较高的活性和芳烃选择性;而Mo/Al2O3或Mo/SiO2催化剂则相对较差。对于乙烷的反应,钼物种的存在更有利于甲烷或乙烯的生成,芳烃选择性相对较低。钼物种较强的断键能力可能是使甲烷C-H键活化的原因。 相似文献