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31.
《Robotics and Autonomous Systems》2006,54(5):353-360
In this paper we present a robot control architecture for learning by imitation which takes inspiration from recent discoveries in action observation/execution experiments with humans and other primates. The architecture implements two basic processing principles: (1) imitation is primarily directed toward reproducing the outcome of an observed action sequence rather than reproducing the exact action means, and (2) the required capacity to understand the motor intention of another agent is based on motor simulation. The control architecture is validated in a robot system imitating in a goal-directed manner a grasping and placing sequence displayed by a human model. During imitation, skill transfer occurs by learning and representing appropriate goal-directed sequences of motor primitives. The robustness of the goal-directed organization of the controller is tested in the presence of incomplete visual information and changes in environmental constraints. 相似文献
32.
重点探讨了欧洲能源交易市场的市场结构和运作特点。欧洲能源交易市场是欧洲大陆上最大的能源交易场所,因此对市场参与者的管理是交易所的重要任务。欧洲能源交易市场建立了大量的规章制度来规范交易参与者的行为,以规避交易参与者联合操纵市场的风险。 相似文献
33.
M. Muhr S. Pack S. Jaufer H. Lugschitz 《e & i Elektrotechnik und Informationstechnik》2006,123(12):537-543
New developments in diagnostic tools and systems are necessary for a reliable and economic evaluation of the condition of
equipment in power systems. In a research project a tool for the condition of contacts of centre break disconnector, which
is used under normal operation by the aid of a thermography measurement system, has been developed. In this paper, an overview
about the laboratory investigation of the temperature load behaviour and the environmental influence on-site for new and aged
disconnector contacts are given. A condition evaluation tool for contacts, which was the aim of the project, has been created.
The basic method for the evaluation is presented, and also two additional easements for a fast identification of suspect contacts
are presented. With this evaluation tool and the usage of a thermography based measuring system, a condition based maintenance
strategy can be applied, whereby an early detection of damages is possible and so power quality and reliability increase.
相似文献
34.
变权组合预测模型在大坝安全监测中的应用 总被引:1,自引:1,他引:0
简要介绍了组合预测模型的基本原理,该模型改进了单一模型考虑因素的片面性,但常规的组合预测模型的权系数是固定的。考虑到各种模型的预测精度的变化,以及大坝安全监测数据存在的突变、时效等因素,固定权系数的组合预测模型有待进一步改进。文中提出了变权系数组合预测模型,并将其用于实际的大坝安全监测工程。结果表明,变权组合预测模型的预报精度高于其他模型。是一种值得推广的方法。 相似文献
35.
This paper discusses the challenges that the US electric power industry has to face to continue to maintain the stable, reliable, and efficient system over the next few years. These challenges include an aging transmission system suffering from substantial underinvestment, the need for a regulatory framework that will spur independent investment, ownership and management of the nation's grid, and an aging workforce and the need for a succession plan to ensure the existence of the next generation of technical expertise in the industry. Through the efforts of many and by working together through concerned organizations, the industry can move forward to the benefit of the public and the US as a whole. 相似文献
36.
蔡清伟 《广东输电与变电技术》2003,(4):49-52
本文提出了建立新一代的开放式自动抄表平台的思想,并着重介绍了构建平台的基本原则、技术要求和设计方式。 相似文献
37.
Dilute solution viscometry was used to explore the effect of solid-state ageing on the interactions that occur between guar
gum and water. The resulting data set, derived from nearly 700 independent experiments, led to a value for the Flory–Huggins
interaction parameter, χ, of 0.56 ± 0.12. This value, which appeared independent of ageing, is in good agreement with the
majority of published data. The effect of ageing on molar mass was also explored, using Mark–Houwink–Sakurada (MHS) theory.
Absolute molar mass values were found to depend sensitively on the choice of MHS constants, but the effect of ageing was unequivocal;
under all conditions, it resulted in a pronounced decrease in molar mass. In concert, these results strongly suggest that,
in guar, solid-state ageing reactions are largely associated with scission of the molecular backbone. This hypothesis was
then tested by infra-red and Raman spectroscopy. Although infra-red spectroscopy did reveal some subtle differences between
the spectra of guar and locust bean gum (LBG), a related polysaccharides with a different galactose:mannose ratio, no equivalent
effects were seen in aged guar. However, clear differences between the Raman spectra of guar and LBG were seen, demonstrating
that the technique is well capable of revealing changes in galactose:mannose ratios. Examination of aged guar samples revealed
no comparable effects, reinforcing the notion that, in this polysaccharide, chain scission reactions dominate such that solid-state
ageing does not lead to changes in the nature of its interaction with water. 相似文献
38.
Blends of linear and branched polyethylene were prepared covering the composition range 1–20% linear polyethylene, and three
thermal treatments were subsequently chosen to produce a range of different morphologies. Isothermal crystallization at 124
°C gives rise to compact linear inclusions within a matrix of branched polyethylene, isothermal crystallization at 115 °C
produces an open, banded spherulitic morphology and, finally, quenching leads to a continuous spherulitic texture. Ramp testing
was then employed to investigate the effect of morphology on electrical strength. It was found that the electrical strength
of the blend depends primarily on the morphology and that, by optimizing thermal treatment and linear polyethylene content,
substantial improvements in properties can be obtained.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
39.
《Applied Energy》2005,80(1):61-66
A new method and algorithm for functional reliability simulation for a steam-turbine's behaviour is proposed and a degeneration model is established based on the laws of the steam-turbine. By taking a power-station steam-turbine as an example, the turbine's functional reliability is simulated. 相似文献
40.
郭伟 《计算机与数字工程》2012,40(10):159-161
在PI3000平台中任务调度是应用系统中很重要的部分,应用环境的复杂程度导致各式各样调度的框架和算法.文中提出一个新的分布式负载均衡的任务调度框架,以解决在并行任务中特定的应用环境下的任务调度问题.这个框架是动态的、可重用的,通过提供给各种不同的资源环境对应的接口,来进行跨服务的调度.整个框架关注于实际应用环境下任务、资源的动态不稳定性和任务计算的快速响应. 相似文献