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81.
In developing an intelligent mobile construction robot, a navigation system that can provide an effective and efficient path-planning algorithm is a very important element. The purpose of a path-planning method for a mobile construction robot is to find a continuous collision-free path from the initial position of the construction robot to its target position. This paper presents an improved Bug-based algorithm, called SensBug, which can produce an effective path in an unknown environment with both stationary and movable obstacles. The contributions, which make it possible to generate an effective and short path, are an improved method to select local directions, a reverse mode, and a simple leaving condition. Some emerging technologies that can be used for implementing an intelligent construction robot are introduced in this paper. 相似文献
82.
杨文静 《广东工业大学高等工程教育研究》2007,7(1):23-25
信用经济是市场经济发展到一定阶段的必然趋势和客观要求。在这种经济中,信用不仅仅是作为交换媒介存在,更为重要的是信用作为除市场以外的另一种资源配置方式。它的产生需要一些特定的条件,文章即从个人、企业、政府三方面信用建设入手,提出创建信用经济条件产生的具体措施。 相似文献
83.
Delevoye-Turrell Yvonne; Giersch Anne; Wing Alan M.; Danion Jean-Marie 《Canadian Metallurgical Quarterly》2007,116(1):56
Many everyday activities depend on the capacity to organize and smoothly execute motor sequences. The authors tested the hypothesis that a sequencing deficit is associated with schizophrenia. They used a new method to distinguish between lower and higher order mechanisms for the impairment. The 1st task involved triggered sequences in which sensory information from 1 movement was the cue for initiation of the following movement. Results showed that the motor sequences were performed as fluently in patients as in controls. The 2nd and 3rd tasks involved sequences in which the entire movement sequence could be preplanned. Patients executed the sequences less fluently than controls but only under the condition where action sequences were required. Furthermore, the patients' fluency deficit increased with sequence complexity. The high discrimination power of Task 3 gave the authors a means to control for a potential psychometric confound involving differential discriminating power and to argue in favor of a specific higher order motor fluency deficit in patients with schizophrenia. It is suggested that basic lower order mechanisms that integrate sensory information with outgoing motor commands are preserved in schizophrenia, whereas higher order integrative mechanisms that are required for the smooth coordination of motor sequences are impaired. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
84.
We present a method based on extended linear real quantifier elimination for multiple object semilinear motion planning, i.e. finding collision-free trajectories for several robots in a time dependent environment. For practical applicability the method is limited to polygonal objects and linear trajectories. It can, however, deal with situations involving even non-convex objects. 相似文献
85.
86.
In this article, linear programming and fuzzy optimization models are developed for planning and management of available land-water-crop system of Mahanadi-Kathajodi delta in eastern India. The models are used to optimize the economic return, production and labour utilization, and to search the related cropping patterns and intensities with specified land, water, fertilizer and labour availability, and water use pattern constraints. Due to extreme backwardness of the study area, it has been decided to keep all the three objectives of the linear programming models at the same priority level to obtain the compromised solution in a fuzzy environment that incorporates the imprecision in fuzzy goals and fuzzy constraints. These non-structural models facilitate the conjunctive use of available surface water and groundwater resources. A comparative evaluation along with the benefit-cost ratios of the existing and proposed farming systems is also presented. 相似文献
87.
本文利用模糊集理论,提出一种非确定环境的描述方法,并且针对机器人在该类环境中的避障轨迹规划,建立了相应的决策函数和规划策略,最后,给出在PC-386计算机上的仿真试验结果。 相似文献
88.
T.J. Williams P. Bernus J. Brosvic D. Chen G. Doumeingts L. Nemes J.L. Nevins B. Vallespir J. Vlietstra D. Zoetekouw 《Control Engineering Practice》1994,2(6):939-960
This paper is a summary of the major technical report (Williams et al., 1993) of the IFAC/IFIP Task Force on Architectures for Integrating Manufacturing Activities and Enterprises. It presents a synopsis of the investigations of pertinent architectures undertaken, and the findings generated relating to the suitability of various architectures for the integration task. It also presents the Task Force's recommendations for achieving a “complete” architecture in terms of the necessary capabilities by “completing” a currently available architecture. The Task Force also outlined how a “best” architecture could be achieved by selecting and combining the best features of the available architectures. 相似文献
89.
90.
ATM网络的可用比特率业务 总被引:2,自引:0,他引:2
本文介绍了可用比特率业务的业务特点,速率控制机制以及该业务存在的问题。 相似文献