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11.
Christopher Rasmussen 《Autonomous Robots》2008,25(3):205-229
We present a vision- and ladar-based approach to autonomous driving on rural and desert roads that has been tested extensively
in a closed-loop system. The vision component uses Gabor wavelet filters for texture analysis to find ruts and tracks from
which the road vanishing point can be inferred via Hough-style voting, yielding a direction estimate for steering control.
The ladar component projects detected obstacles along the road direction onto the plane of the front of the vehicle and tracks
the 1-D obstacle “gap” presumed due to the road to yield a lateral offset estimate. Several image- and state-based tests to
detect failure conditions such as off-road poses (i.e., there is no road to follow) and poor lighting due to sun glare or
distracting shadows are also explained. The system’s efficacy is demonstrated with analysis of diverse logged data including
from the 2005 DARPA Grand Challenge, as well as tests with full control of a vehicle over 15 km of difficult roads at up to
37 km/h with no waypoints.
相似文献
Christopher RasmussenEmail: |
12.
With IPv6 transitioning still in a relative state of flux, the need has emerged for methods to control this crucial aspect of IPv6 deployments. This article makes the case for transitioning architectures as a realistic solution to this issue, specifically within large-scale networks. The Site Transitioning Architecture (STA) supports the deployment, operation, and management of IPv6 transitioning mechanisms. The authors provide an overview of the STA's design and operation, noting that its flexible, simple, and secure architecture is suitable for the duration of the IPv6 deployment process, regardless of the underlying network environment. 相似文献
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Dehen CJ Everly RM Plocinik RM Hedderich HG Simpson GJ 《The Review of scientific instruments》2007,78(1):013106
A new instrument was constructed to perform discrete retardance nonlinear optical ellipsometry (DR-NOE). The focus of the design was to perform second harmonic generation NOE while maximizing sample and application flexibility and minimizing data acquisition time. The discrete retardance configuration results in relatively simple computational algorithms for performing nonlinear optical ellipsometric analysis. NOE analysis of a disperse red 19 monolayer yielded results that were consistent with previously reported values for the same surface system, but with significantly reduced acquisition times. 相似文献
17.
Christopher Jefferson Angela Miguel Ian Miguel S. Armagan Tarim 《Computers & Operations Research》2006
Peg Solitaire is a well known puzzle, which can prove difficult despite its simple rules. Pegs are arranged on a board such that at least one ‘hole’ remains. By making draughts/checkers-like moves, pegs are gradually removed until no further moves are possible or some goal configuration is achieved. This paper considers the English variant, consisting of a board in a cross shape with 33 holes. Modelling Peg Solitaire via constraint or integer programming techniques presents a considerable challenge and is examined in detail. The merits of the resulting models are discussed and they are compared empirically. The sequential nature of the puzzle naturally conforms to a planning problem, hence we also present an experimental comparison with several leading AI planning systems. Other variants of the puzzle, such as ‘Fool's Solitaire’ and ‘Long-hop’ Solitaire are also considered. 相似文献
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Describes 5 means of maintaining standards for psychological practice that are currently used in the US: (1) general and criminal law, (2) peer control, (3) federal regulations, (4) state boards of examiners in psychology, and (5) civil malpractice litigation. Their relevance to the Canadian context is discussed, especially with respect to the more restricted role of the Canadian federal government in professional affairs, the lower profile for civil rights, and the lower incidence of civil litigation in Canada. Recommendations made to ensure the exemplary practice of psychology include the increased use of peer control through peer review committees, increased organization of professional practice at the national level, and a closer liaison between professional associations and governing boards at the provincial level. (7 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
19.
Liang Christopher T. H.; Alvarez Alvin N.; Juang Linda P.; Liang Mandy X. 《Canadian Metallurgical Quarterly》2007,54(2):132
On the basis of stress and coping theory, the authors examined coping as a mediator of the relationship between perceptions of racism and racism-related stress with a sample of Asian American college students (N = 336). Results indicated that coping mediated the relationship between racism and racism-related stress differentially by gender. The more that men perceived racism, the more likely they were to use support-seeking coping strategies that were associated with higher levels of racism-related stress. The more that women perceived racism, the more they used active coping strategies that were associated with higher levels of racism-related stress. The findings demonstrate how coping with racism differs for Asian Americans on the basis of gender. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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