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121.
袁嘉晖 《江汉石油职工大学学报》2013,26(4):16-18
以桂中地区复杂山地弯宽线地震资料采集为例进行不同观测系统叠加试验,分析不同覆盖次数的观测系统对资料的成像效果、信噪比、能量和频率的影响。宽线放炮或者交叉放炮可以改善接收方向上各项异性的接收效果,可以更好压制散射、侧面波、规则干扰等干扰波。因此高覆盖次数叠加可以很好的压制噪音。随着覆盖次数的增加剖面能量增强,信噪比增加,但覆盖次数高,剖面频率降低。 相似文献
122.
针对不良行为传播过程难以分析的问题,提出一种基于复杂网络理论和系统动力学的模拟演化方法.该方法将团队映射为复杂网络,建立具有易染态、不良态、改良态、移除态、离职态的SBIRD模型,并结合权值度和簇系数对模型中的传播率、消除率、改良率等参数以及系统初始值加以实例分析.实例仿真表明:该方法能够有效地对不良行为传播过程进行分析,并辅助企业对团队中不良行为实施管理与控制. 相似文献
123.
Jau-Kai Wang 《Desalination》2004,161(3):277-285
Preferential transport behaviors of metal ions for ternary ions system through a cation exchange membrane were studied in a stirred batch dialyzer. Cu2+-Fe3+-Ni2+ was chosen for the experimental investigation. Oxalic acid, malonic acid, citric acid, and ethylenediaminetetraacetic acid were employed as a complex agent used in the investigated solution in order to increase the discrepancy between transport fluxes of metal ions. The experimental results show that the order of effective complex agents is malonic acid > citric acid > oxalic acid > ethylenediaminetetraacetic acid. The preferential transport behavior of metal ions depends on the stoichiometric ratio of the complex agent to metal ions and the pH value of the feed solution, but is independent of the concentration of counterion in the stripping phase. The optimal results of JNiJCu: JFe can be attained about 30 : 10 : 1. 相似文献
124.
Masato Yamamura Toshihisa Kajiwara Hiroyuki Kage 《Chemical engineering science》2003,58(17):3891-3899
We present a compact formula for describing the mean frictional forces acting on a molecule in multicomponent systems. The friction-based diffusion theory of Zielinski and Hanley was extended to newly include the friction-average molar velocity as a reference frame. The results showed that the previous diffusion theories are unified by the friction-average concept by properly choosing the average velocity. The present model based on the diffusivity-related molar average velocity provides better predictions for the diffusive flux in a ternary miscible liquid compared to the other existing theories. The application of the model in phase-separating ternary systems revealed that the introduction of a highly diffusive third component into demixing polymer blends promotes a particular enhancement of the spinodal decomposition due to the difference in the frictional interactions between polymers. 相似文献
125.
针对不确定性知识难以量化.摸铷控制器曲隶属函数不容易确定等问题.提出了一种区间值横期产生式规则.建立模糊控制规则模型,给出了区间值模糊匹配函数定义,在此基础上给出了区间值模糊推理方法。该方法更有利于模期规则的精确匹配.应用到实际工业控制对象,能更好的反映领域专家的决策思维和推理过程。 相似文献
126.
127.
We review, unify and extend work pertaining to evaluating mode mixity of interfacial fracture utilizing the virtual crack
closure technique (VCCT). From the VCCT, components of the strain energy release rate (SERR) are obtained using the forces
and displacements near the crack tip corresponding to the opening and sliding contributions. Unfortunately, these components
depend on the crack extension size, Δ, used in the VCCT. It follows that a mode mixity based upon these components also will
depend on the crack extension size. However, the components of the strain energy release rate can be used for determining
the complex stress intensity factors (SIFs) and the associated mode mixity. In this study, we show that several—seemingly
different—suggested methods presented in the literature used to obtain mode mixity based on the stress intensity factors are
indeed identical. We also present an alternative, simpler quadratic equation to this end. Moreover, a Δ-independent strain
energy release based mode mixity can be defined by introducing a “normalizing length parameter.” We show that when the reference
length (used for the SIF-based mode mixity) and the normalizing length (used for Δ-independent SERR-based mode mixity) are
equal, the two mode mixities are only shifted by a phase angle, depending on the bimaterial parameter ε. 相似文献
128.
The influence of complex dopants including donor and acceptor ions on microstructure and electrical properties of PZT (Zr/Ti
= 53/47) ceramics was investigated. The prepared PZT ceramics modified with complex soft dopants, La+3 and Nb+5, showed that the piezoelectric properties were enhanced and stable with the compositional variations, which made it possible
to establish the higher reliability and reproducibility of the piezoelectric performances. For 1.0 mol% La and 1.2 mol% Nb
doped composition, the maximum value, k
P
= 0.66, was obtained. Unlike single element doping, the complex doping of both the donor and acceptor ions caused various
compensation effects for the piezoelectric properties of the PZT ceramics. The improved piezoelectric properties, i.e., enhanced
Q
m
with remaining higher k
p
, were obtained in the PZT composition complexly doped with La+3 and Fe+3. For 1.0 mol% La and 2.0 mol% Fe doped PZT composition, relatively high Q
m
and k
p
values of 580 and 0.53, respectively, were obtained. It was also shown that the PZT composition had the rather lowered dielectric
constant, ε
r
= 800, and considerably low loss, tanδ = 0.003. By changing the dopants compositions, the properties can also be tailored
over wider range. 相似文献
129.
在实际工业现场,控制系统的复杂性不仅表现在结构上,更多的是表现在信息关系的不确定性和复杂程度上,对这类被控对象进行有效控制的关键是选取适合对象的控制策略。 相似文献
130.
西方权威“自涉与悖论”论点批判——禁止“矛盾”,殃及“自涉” 总被引:2,自引:3,他引:2
黄展骥 《重庆理工大学学报(自然科学版)》2006,20(7):7-12
对西方维特根斯坦、哥德尔、罗素、哈克、冯·赖特、克里普克、马丁、塔斯基、本奇、森斯伯里、皮亚斯、芬斯勒、鲍茨瓦、莱辛巴哈等权威有关“矛盾、自涉、意义、悖论”等问题的观点进行了批判。讨论了有关“自涉”与“悖论”的最新重点。 相似文献