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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
We consider the symmetric formulation of the interior penalty discontinuous Galerkin finite element method for the numerical
solution of the biharmonic equation with Dirichlet boundary conditions in a bounded polyhedral domain in
. For a shape-regular family of meshes consisting of parallelepipeds, we derive hp-version a priori bounds on the global error measured in the L2 norm and in broken Sobolev norms. Using these, we obtain hp-version bounds on the error in linear functionals of the solution. The bounds are optimal with respect to the mesh size h and suboptimal with respect to the degree of the piecewise polynomial approximation p. The theoretical results are confirmed by numerical experiments, and some practical applications in Poisson–Kirchhoff thin
plate theory are presented. 相似文献
993.
Bubb H 《Applied ergonomics》2006,37(4):401-407
In this article, it is shown that human work can be understood as a process of creating order, and that order can be seen as a form of information. Since information can be considered as negative entropy, work is associated with energy consumption. Therefore, it is important to investigate the nature of human necessities in more detail in order to meet the desire for comfort through the efficient application of energy. Temporary increases of information cause accelerated increases in entropy. This explains the appearance of living organisms, and the historic development of increasingly complex technology. Through technical progress, repetitive human work is being replaced by automation, so that primarily creative work remains. Now the question arises of how much creative work a human can manage. In addition, one goal of automation should be the reduction of human errors, but in doing so, an optimal balance should be found between supporting the operator both during normal procedures and during unforeseen circumstances. 相似文献
994.
The release of the Institute of Medicine (Kohn et al., 2000) report "To Err is Human", brought attention to the problem of medical errors, which led to a concerted effort to study and design medical error reporting systems for the purpose of capturing and analyzing error data so that safety interventions could be designed. However, to make real gains in the efficacy of medical error or event reporting systems, it is necessary to begin developing a theory of reporting systems adoption and use and to understand how existing theories may play a role in explaining adoption and use. This paper presents the results of a 9-month study exploring the barriers and facilitators for the design of a statewide medical error reporting system and discusses how several existing theories of technology acceptance, adoption and implementation fit with many of the results. In addition we present an integrated theoretical model of medical error reporting system design and implementation. 相似文献
995.
本文提出一种自适应模糊控制器并将之用于机器人轨迹跟踪控制 ,该控制器采用控制器输出误差方法 (COEM) ,根据控制器的输出误差而不是对象的输出误差来在线地调整模糊控制器的参数 ,无须对对象进行辩识 .仿真结果表明该控制器用于机器人轨迹跟踪控制具有很好的性能 ,是一种有效的控制器 相似文献
996.
In this paper we present a framework that combines some ideas of the behavioral modeling approach and the prediction error modeling approach. It is shown that the proposed model selection procedure can be rephrased as an optimization problem that only depends on the model parameters. Experiments illustrate the potential of the so-called misfit versus latency framework. 相似文献
997.
Flip Korn Alexandros Labrinidis Yannis Kotidis Christos Faloutsos 《The VLDB Journal The International Journal on Very Large Data Bases》2000,8(3-4):254-266
Association Rule Mining algorithms operate on a data matrix (e.g., customers products) to derive association rules [AIS93b, SA96]. We propose a new paradigm, namely, Ratio Rules, which are quantifiable in that we can measure the “goodness” of a set of discovered rules. We also propose the “guessing
error” as a measure of the “goodness”, that is, the root-mean-square error of the reconstructed values of the cells of the
given matrix, when we pretend that they are unknown. Another contribution is a novel method to guess missing/hidden values
from the Ratio Rules that our method derives. For example, if somebody bought $10 of milk and $3 of bread, our rules can “guess”
the amount spent on butter. Thus, unlike association rules, Ratio Rules can perform a variety of important tasks such as forecasting,
answering “what-if” scenarios, detecting outliers, and visualizing the data. Moreover, we show that we can compute Ratio Rules
in a single pass over the data set with small memory requirements (a few small matrices), in contrast to association rule mining methods
which require multiple passes and/or large memory. Experiments on several real data sets (e.g., basketball and baseball statistics,
biological data) demonstrate that the proposed method: (a) leads to rules that make sense; (b) can find large itemsets in
binary matrices, even in the presence of noise; and (c) consistently achieves a “guessing error” of up to 5 times less than
using straightforward column averages.
Received: March 15, 1999 / Accepted: November 1, 1999 相似文献
998.
999.
孙玉浩 《河北水利水电技术》2013,(6):92-94
介绍了全球卫星定位系统(GNSS)在测绘工作中的应用发展历程,讲述了采用RTK技术获取的WGS84坐标转换到地方坐标的方法,结合工程数据进行了坐标转换研究,得出了三参数、四参数及七参数坐标转换方法的应用范围及使用条件。 相似文献
1000.
受转向或侧向风影响,无人驾驶车在运行的过程中易产生失稳.采用了模糊神经网络PID算法,将系统输出偏差的变化量,经模糊化后输入到神经网络PID控制器中,对车辆的质心侧偏角、横摆角速度进行调整,达到控制车辆平稳运行的目的.在不同的工况下对算法的有效性进行了试验分析.结果表明,该算法使系统响应超调减少,反应时间加快,具有较强的抗干扰性. 相似文献