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121.
The development of autonomous mobile machines to perform useful tasks in real work environments is currently being impeded
by concerns over effectiveness, commercial viability and, above all, safety. This paper introduces a case study of a robotic
excavator to explore a series of issues around system development, navigation in unstructured environments, autonomous decision
making and changing the behaviour of autonomous machines to suit the prevailing demands of users. The adoption of the Real-Time
Control Systems (RCS) architecture (Albus, 1991) is proposed as a universal framework for the development of intelligent systems. In addition it is explained how the use
of Partially Observable Markov Decision Processes (POMDP) (Kaelbling et al., 1998) can form the basis of decision making in the face of uncertainty and how the technique can be effectively incorporated into
the RCS architecture. Particular emphasis is placed on ensuring that the resulting behaviour is both task effective and adequately
safe, and it is recognised that these two objectives may be in opposition and that the desired relative balance between them
may change. The concept of an autonomous system having “values” is introduced through the use of utility theory. Limited simulation
results of experiments are reported which demonstrate that these techniques can create intelligent systems capable of modifying
their behaviour to exhibit either ‘safety conscious’ or ‘task achieving’ personalities. 相似文献
122.
András Ványolos Balázs Dóra Attila Virosztek 《Journal of Superconductivity and Novel Magnetism》2007,20(7-8):643-645
We report of a theoretical study on quasi-one dimensional unconventional charge density wave (UCDW) driven by electron–phonon
interaction. Within mean field theory, we find that the wavevector dependence of the coupling leads to a momentum dependent
single particle gap on the Fermi surface. The presence of small energy single particle excitations around the gap nodes significantly
changes the optical conductivity compared to the conventional CDW result. In addition to that, the collective phase excitation
arising from fluctuation of the order parameter leads to further qualitative changes of the conductivity and results in an
effective mass that is nonmonotonic in temperature.
相似文献
123.
124.
本文介绍了在自由口通信模式下,用计算机读写S7—200PLC存储区内相邻的多个字节数据的通信程序设计方法,程序设计中采用了多种可靠性措施。 相似文献
125.
对江苏省县级电力信息网工程采用的利用ATM设备、SDH设备和WDM设备的3种组网方案进行了阐述,并分析了各种方案的优缺点。 相似文献
126.
数字多媒体广播(DMB)是从数字音频广播(DAB)基础上发展起来的一种新型广播技术。数字音频广播是在调幅AM和调频FM之后的第三代广播技术。通过对数字多媒体技术的介绍较全面地阐述了其技术系统、功能、现状及发展前景。 相似文献
127.
乙烯装置失效模式分析及基于风险的检验 总被引:1,自引:0,他引:1
简述了乙烯装置的工艺流程,分析了装置中常见的几种失效模式及其分布;以乙烯裂解装置为例,简述了RBI的执行过程和结果,从基于风险的检验理念,对制订设备检验策略提出了几点建议。 相似文献
128.
介绍了神经网络与线性分组码之间的关系,并在文献[1]的基础上证明了软判决译码与求解能量函数最大值之间的等价性,然后以(7,4,3)汉明码为例介绍了神经网络在循环码硬判决、软判决译码中的应用。 相似文献
129.
Product optimization involves selecting design, manufacturing, and support attributes that can produce the best system. Producibility or manufacturability is the term often used to describe the relative ease of manufacturing a product. In complex systems, productibility optimization is a very difficult process, particularly when the values of many attributes are restricted by constraints. One challenge is to develop more universal producibility metrics for the conceptual design phase when design information is limited and drawings are nondimensional. This paper develops a new method for producibility optimization in conceptual design based on a combination of both decision theoretic and expert system techniques. Decision theoretic techniques provide the means to model the design for producibility problem in a manner that can deal with risk, uncertainty, and user (or corporate) preferences, and can effectively integrate diverse factors to provide a measure of the overall worth of a design. The particular decision theoretic approach employed is based on multi-attribute utility theory. An illustrative example of the methodology is applied to the conceptual design of a structural composite part. 相似文献
130.