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This paper describes a simple vision-based mapping system for mobile robot navigation in an unknown outdoor environment, consistent with the efforts of Georgia Tech's team for the DARPA-sponsored Learning Applied to Ground Robots (LAGR) project. This approach, which has been robust to different environments and responsive to time-critical constraints, is a good example of robotics in practice. 相似文献
654.
Yu. G. Vasin A. D. Krakhnov T. Sh. Utesheva 《Pattern Recognition and Image Analysis》2006,16(1):104-105
The development of efficient techniques for converting information obtained from complicated graphical documents into a digital
form is considered. It is shown that the use of discrete geometry methods make it possible to improve the efficiency of many
technological stages.
The work was supported by the Russian Foundation for Basic Research, project no. 00-15-96018 and by the Integration Foundation,
project no. K-03392. 相似文献
655.
Simple interconnection of high-speed local area networks (LAN's) can be accomplished without special technology through the use of table-free bridges. Self-guided frame routing allows frames to trace specific routes through bridged LAN's without requiring bridges to maintain address tables or perform table lookups. As a result, the technique applies to networks regardless of their operating speed or topological configuration and requires no interbridge protocols. The paper discusses a method known as source routing that provides tablefree bridging and self-guided frame routing for LAN's. Participation by the bridges that interconnect pairs of LAN's and by the stations whose frames they forward is described. Possible frame formats are shown as enhancements to the standard frame formats of the IEEE 802 and ISO 8802 local area networks. 相似文献
656.
M.D. Mikhailov M.N. Özişik 《International Communications in Heat and Mass Transfer》1985,12(4):393-404
A new, powerful method of analysis, involving the combined use of finite integral transform and finite element techniques, is presented for the solution of time dependent heat flow systems composed of many one-dimensional elements connected through the nodes. This method leads to an eigenvalue problem which is not of the conventional Sturm-Liouville type. A procedure for the determination of the eigenvalues is described. The solution obtained is in the form of an infinite series and contains quasi-steady and transient terms. The general solution obtained can be applied in the mathematical modelling of many engineering applications such as the determination of the penetration of the daily temperature cycle into buildings, the analysis of heat transfer in array of extended surfaces in compact heat exchangers, and many others. 相似文献
657.
A finite element formulation applicable to the general shell of revolution is presented for the stress and stability analysis of toroidal pressure vessels under hydrostatic pressure. Considering the follower force effect of the external pressure, linear bifurcation buckling loads and corresponding mode shapes have been obtained in both axially and equatorially symmetric as well as antisymmetric buckling modes. Calculated critical values are compared with results of other investigations. 相似文献
658.
H Loncar-Stevanovi? Z Vujovi? A Drazi? D Lazi? S Jakuli? T Jovanovi? 《Canadian Metallurgical Quarterly》1998,17(3-4):331-337
alpha-Crystallins possess molecular chaperone properties and are one of the most abundant of the lenticular proteins. Posttranslational modifications of these proteins have been implicated as a possible etiology of human cataracts. This article will review current knowledge concerning the effects of known posttranslational modifications upon the molecular chaperone properties and aggregation behavior of alpha-A and alpha-B crystallin. Based upon these effects, experimental approaches will be discussed that may be useful in the development of reagents that may selectively inhibit the cataractogenic process in the aging human lens. 相似文献
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