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101.
This paper presents Bayes estimators for the reliability measures of the individual components in a multi-component systems in the presence of masked system life test data. The life time distributions of the system components are assumed to be geometric with different parameters. Two-sided Bayesian probability intervals of the parameters are also derived. Numerical simulation study is given in order to: (i) explain how one can apply the theoretical results obtained, (ii) study the influence of the sample size and masking level on the accuracy of point estimates. 相似文献
102.
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
103.
Excel在大学物理实验中的应用 总被引:1,自引:0,他引:1
利用Excel的强大功能,对实验数据进行处理、分析,对实验过程及实验结果的监控。 相似文献
104.
Interventions for a variety of emotional and behavioral problems are commonly delivered in the context of treatment groups, with many using rolling admission to sustain membership (i.e., admission, dropout, and discharge from group are perpetual and ongoing). The authors present an overview of the analytic challenges inherent in rolling group data and outline commonly used (but flawed) analytic and design approaches to addressing (or sidestepping) these issues. Moreover, the authors propose use of latent class pattern mixture models (LCPMMs) as a statistically and conceptually defensible approach for modeling treatment data from rolling groups. The LCPMM approach is illustrated with rolling group data from a group-based alcoholism pilot treatment trial (N = 128). Different inferences were made with regard to treatment efficacy under LCPMM vs. the commonly used standard group-clustered latent growth model (LGM); coupled with other preliminary findings in this area, inferences from LGMs may be overly liberal when applied to data from rolling groups. Continued work on data analytic difficulties in groups with membership turnover is critical for furthering the ecological validity of research on behavioral treatments. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
因为价格机制不能正常运行和不能正常发挥作用,或者因为社会经济活动的相关性,传媒产品的生产出现外在性现象,社会成本问题不可避免.选择合适的产权制度安排,不仅能够消除传媒产品生产的外在性,而且有利于传媒资源的有效利用和传媒经济的不断发展. 相似文献
106.
107.
介绍了利用ASP技术对图书馆主页上的光盘数据库进行远程维护,给出整个实施过程的步骤及部分程序的源程序。 相似文献
108.
对自动化在选矿工业中应用的意义进行了论述。结合堆浸选矿的工艺特点,介绍了金矿选厂自动化系统的构成和自动化系统实现的基本功能。 相似文献
109.
Kaushik A. Iyer 《International Journal of Fracture》2007,146(1-2):1-18
Internal fracture patterns developed in silicon carbide cylindrical targets as a result of dynamic indentation (63–500 m/s)
by tungsten carbide spheres are defined. Microscopy of recovered and sectioned targets delineate into three regions, each
associated with distinct cracking modes, i.e., shallow cone macrocracking at and near the impact surface, steep interior cone
macrocracks that radiate into the target from the impact region and local grain-scale microcracking directly underneath the
impact region. The observed fracture patterns are found to maintain a noticeable degree of self-similarity upto the impact
velocity of 500 m/s. Linear elastic analysis of the full (surface and interior) stress field developed under static (Hertz)
contact loading delineate the target into four regions, based on the number of principal stresses that are tensile (none,
1, 2 or all 3). A strong correlation is found between the principal stress conditions within each region and the forms of
cracking, their locations and orientations present therein. This correlation has a number of implications, including non-interaction
of crack systems, which are discussed. Illustrative linear elastic fracture mechanics analyses are performed for three regions,
and calculated and observed macrocrack lengths are found to be in reasonable agreement. 相似文献
110.
针对回转窑在运行过程中窑体变形的情况开发了一种监测与报警系统。完成了系统的前向通道设计、单片机与PC机的串行通讯设计和报警显示。 相似文献