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多目标模糊全局优化设计方法和软件 总被引:2,自引:0,他引:2
分析了优化设计在土木工程中应用不够广泛的原因,由此提出了一个能用于工程设计的多目标模糊全局优化设计方法。介绍了按该方法研制的软件MFD的功能和性能,以及一个用该软件分析的拱坝体型设计实例。 相似文献
23.
During the day, there are considerable variations in the climatic factors prevailing in these regions. This is especially so during the 24-hour daily cycle of the long, hot and dry summer (mid-May to midOctober). Such climatic conditions have had a considerable impact on the daily living pattern of family life in the same season, particularly in the urban areas. During the same 24-hour cycle, they have compelled the inhabitants to shift their living activities both vertically in section and horizontally in plan; they do this in pursuit of more acceptable, if not, desirable internal thermal environmental ambience. 相似文献
24.
炼钢厂在贯彻落实《做强莱钢技术支撑体系》过程中,系统思考,全面优化,多措并举,重点突破,通过工艺管理升级、工艺技术升级和装备水平升级的一揽子计划,实现了产品实物质量升级的目标。 相似文献
25.
主要讨论了多项式正交滤波器和共轭正交滤波器组的构造方法,首先利用Riesz引理和特殊的余弦三角形多项式,给出了一种多项式正交滤波器的构造算法,该算法可以构造出一系列特性各异的紧支撑正交小波基;还给出了由一个矩阵CQFs派生多个新的矩阵CQFs的共轭正交滤波器组算法,包括由低阶矩阵CQFs构造高阶矩阵CQFs。 相似文献
26.
Performance analysis of IEEE 802.11 ad hoc networks in the presence of exposed terminals 总被引:1,自引:0,他引:1
The paper evaluates the performance effects of exposed terminals in IEEE 802.11 ad hoc networks in finite load conditions. It derives analytical models for the estimation of channel utilization and media access delay for IEEE 802.11 ad hoc networks in finite load conditions with and without exposed terminals. The simulation results show that the analytical estimated channel utilization and media access delay metrics are fairly accurate. 相似文献
27.
In the late eighties and up to the beginning of nineties computation of turbulent flows is mostly dominated by RANS (Reynolds
Averaged Navier-Stokes Simulation) type modelling. During the last few years URANS (Unsteady RANS) and LES (Large Eddy Simulation)
type of approaches have been attempted with some success. Yet, there have been many difficulties when LES is applied to practical
engineering problems and to high Reynolds number flows as energy dissipating eddies become really small and mesh resolution
required for a reasonably resolved LES approaches that of DNS (Direct Numerical Simulation). An alternative solution suggested
was to combine RANS and LES, which in general referred to as Hybrid LES. There have been many proposals for combining RANS
and LES in different ways. In this article, some of the issues involved in performing hybrid LES reported in the recent literature
is briefly reviewed. 相似文献
28.
Whereas there exists a vast literature investigating consumer satisfaction ratings of various behavioral interventions, the majority of these studies have been limited to analogue conditions, which may compromise utility and generalization. Additionally, most research has failed to explore multiple-source, multiple-setting data in the investigation of treatment acceptability. This study investigated parent, teacher, and child treatment acceptability ratings derived from field-based conjoint behavioral consultation cases. Data indicate that overall, 67 parents (aged 23-54 yrs), 67 teachers (aged 22-57 yrs), and 67 children (aged 5-15 yrs) rated conjoint behavioral consultation-based behavioral interventions as very to highly acceptable. For parents, interventions with a reductive component were rated as more acceptable than interventions using both positive and negative components; no significant differences were found among teacher and child group ratings. For teachers, there was a positive relationship between (a) intervention complexity and treatment acceptability ratings and (b) problem severity ratings and treatment acceptability ratings... (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
29.
Modified (α‐diimine)nickel(II) catalysts are suitable for ethylene oligomerization reactions. Due to the mechanism (“chain running”), the formation of double‐bond isomers and branched olefins can be observed. The obtained oligomer mixtures show a Schulz–Flory distribution. Increasing ethylene pressure favors the selectivity of α‐olefin formation. The same effect can be observed when Lewis bases like thiophene or furane are added to the oligomerization reaction mixture. These results can be related to an interaction of the additives with the catalytic active species during the oligomerization process. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1356–1361, 2003 相似文献
30.