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91.
Road transport is a significant source of both safety and environmental concerns. With climate change and fuel prices increasingly prominent on social and political agendas, many drivers are turning their thoughts to fuel efficient or ‘green’ (i.e., environmentally friendly) driving practices. Many vehicle manufacturers are satisfying this demand by offering green driving feedback or advice tools. However, there is a legitimate concern regarding the effects of such devices on road safety – both from the point of view of change in driving styles, as well as potential distraction caused by the in-vehicle feedback. In this paper, we appraise the benchmarks for safe and green driving, concluding that whilst they largely overlap, there are some specific circumstances in which the goals are in conflict. We go on to review current and emerging in-vehicle information systems which purport to affect safe and/or green driving, and discuss some fundamental ergonomics principles for the design of such devices. The results of the review are being used in the Foot-LITE project, aimed at developing a system to encourage ‘smart’ – that is safe and green – driving. 相似文献
92.
Noetica is a tool for structuring knowledge about concepts and the relationships between them. It differs from typical information systems in that the knowledge it represents is abstract, highly connected, and includes meta-knowledge (knowledge about knowledge). Noetica represents knowledge using a strongly typed graph data model. By providing a rich type system it is possible to represent conceptual information using formalised structures. A class hierarchy provides a basic classification for all objects. This allows for a consistency of representation that is not often found in “free” semantic networks, and gives the ability to easily extend a knowledge model while retaining its semantics.
Visualisation and query tools are provided for this data model. Visualisation can be used to explore complete sets of link-classes, show paths while navigating through the database, or visualise the results of queries. Noetica supports goal-directed queries (a series of user-supplied goals that the system attempts to satisfy in sequence) and pathfinding queries (where the system finds relationships between objects in the database by following links). 相似文献
93.
N. A. Stanton C. Baber G. H. Walker R. J. Houghton R. McMaster R. Stewart D. Harris D. Jenkins M. S. Young P. M. Salmon 《Cognition, Technology & Work》2008,10(3):209-220
This paper reports on five different models of command and control. Four different models are reviewed: a process model, a
contextual control model, a decision ladder model and a functional model. Further to this, command and control activities
are analysed in three distinct domains: armed forces, emergency services and civilian services. From this analysis, taxonomies
of command and control activities are developed that give rise to an activities model of command and control. This model will
be used to guide further research into technological support of command and control activities. 相似文献
94.
Yang G Stewart CV Sofka M Tsai CL 《IEEE transactions on pattern analysis and machine intelligence》2007,29(11):1973-1989
Our goal is an automated 2D-image-pair registration algorithm capable of aligning images taken of a wide variety of natural and man-made scenes as well as many medical images. The algorithm should handle low overlap, substantial orientation and scale differences, large illumination variations, and physical changes in the scene. An important component of this is the ability to automatically reject pairs that have no overlap or have too many differences to be aligned well.We propose a complete algorithm, including techniques for initialization, for estimating transformation parameters, and for automatically deciding if an estimate is correct. Keypoints extracted and matched between images are used to generate initial similarity transform estimates, each accurate over a small region. These initial estimates are rank-ordered and tested individually in succession. Each estimate is refined using the Dual-Bootstrap ICP algorithm, driven by matching of multiscale features. A three-part decision criteria, combining measurements of alignment accuracy, stability in the estimate, and consistency in the constraints, determines whether the refined transformation estimate is accepted as correct. Experimental results on a data set of 22 challenging image pairs show that the algorithm effectively aligns 19 of the 22 pairs and rejects 99.8% of the misalignments that occur when all possible pairs are tried. The algorithm substantially out-performs algorithms based on keypoint matching alone. 相似文献
95.
We analyze generalization in XCSF and introduce three improvements. We begin by showing that the types of generalizations evolved by XCSF can be influenced by the input range. To explain these results we present a theoretical analysis of the convergence of classifier weights in XCSF which highlights a broader issue. In XCSF, because of the mathematical properties of the Widrow-Hoff update, the convergence of classifier weights in a given subspace can be slow when the spread of the eigenvalues of the autocorrelation matrix associated with each classifier is large. As a major consequence, the system's accuracy pressure may act before classifier weights are adequately updated, so that XCSF may evolve piecewise constant approximations, instead of the intended, and more efficient, piecewise linear ones. We propose three different ways to update classifier weights in XCSF so as to increase the generalization capabilities of XCSF: one based on a condition-based normalization of the inputs, one based on linear least squares, and one based on the recursive version of linear least squares. Through a series of experiments we show that while all three approaches significantly improve XCSF, least squares approaches appear to be best performing and most robust. Finally we show how XCSF can be extended to include polynomial approximations. 相似文献
96.
FM Stewart 《Canadian Metallurgical Quarterly》1993,7(7):1091-1094
High dose chemotherapy with or without total body irradiation and autologous stem cell rescue has proven to be effective treatment to cure patients with relapsed intermediate grade and high grade non-Hodgkin's lymphoma. Important factors for selection of candidates most likely to do well with these approaches include patients whose disease is responsive to conventional therapy and those who have minimal disease volume at the time of transplant. The treatment-related mortality of autologous stem cell transplantation has diminished from 20% to less than 5% with improved supportive care and selection of patients with less advanced disease. Although the treatment-related mortality of allogeneic stem cell transplantation may be as high as 20-40%, a graft versus lymphoma effect may decrease relapse with the result that overall survival is not substantially different between autologous and allogeneic transplantation. The definitive indications for stem cell transplantation include patients who have relapsed with intermediate or high grade NHL. Relative indications include intermediate/high grade non-Hodgkin's lymphoma patients, "high risk" first complete remission (CR), resistant relapse; low grade non-Hodgkin's lymphoma in sensitive or resistant relapse, advanced disease (sensitive or resistant relapse, transformation), first CR (younger patients). Relative contraindications include specific patient profiles such as bulky high grade lymphoma which progresses on appropriate conventional therapy, poor performance status, active serious infection, serious cardiac, renal, pulmonary or liver dysfunction, active, central nervous system (CNS) disease unresponsive to cranial irradiation/intrathecal therapy. For patients with previous marrow involvement or active marrow involvement at the time of harvest or transplant, "purged" autografts, peripheral blood stem cell transplantation and allografts have been used successfully. 相似文献
97.
This paper describes the implementation and evaluation of a nonsanction seat belt law enforcement program in two experimental communities of contrasting size in a state with a mandatory belt law. The main ingredients of the program were seat belt "salutes," public information and education, and limited use of inexpensive economic incentives. Driver shoulder belt use data collected before, during, and after the experimental programs, compared to similar data collected in a comparison community, showed the approach to be effective. While standard seat belt enforcement activities without incentives have been shown to be effective, many police departments, especially in smaller communities, are reluctant to make wholesale increases in seat belt citations. Although requiring some additional level of manpower and resources, a nonsanction approach to seat belt law enforcement can provide an alternate way of increasing belt use in these communities. 相似文献
98.
Specific heat measurements on superconductingLu
2
Fe
3
Si
5
reveal a strong sample dependence of the residual specific heat contribution
s
, belowT
c
, effectively ruling out the possibility of a two-band model. Upper critical fieldH
c2
results for Lu2Fe3Si5, Sc2Fe3Si5, and LaFe4P12 show a very largeH
c2 with an unusual temperature dependence for Lu2Fe3Si5, in contrast to the latter two compounds, implying a strongly sample-dependentH
c2 as well. Intrinsic magnetic impurities arising from structural disorder and defects are possibly the origin of these anomalous superconducting state properties of Lu2Fe3Si5. 相似文献
99.
Eric R. Smith Richard J. Radke Charles V. Stewart 《International Journal of Computer Vision》2012,97(1):2-17
We present a new framework for detecting, describing, and matching keypoints in combined range-intensity data, resulting in
what we call physical scale keypoints. We first produce an image mesh by backprojecting associated 2D intensity images onto
the 3D range data. We detect and describe keypoints on the image mesh using an analogue of the SIFT algorithm for images with
two key modifications: the process is made insensitive to viewpoint and structural discontinuities using a novel bilinear
filter, and a physical scale space is constructed that exploits the reliable range measurements. Keypoints are matched between
scans only when their physical scales agree, avoiding many potential false matches. Finally, the matches are rank-ordered
using a new quality measure and supplied to a registration algorithm that refines each match into a rigid transformation for
the entire scan pair. We report experimental results on keypoint detection and matching and range scan registration and verification
in a set of difficult real-world scan pairs, showing that the new physical scale keypoints are demonstrably better than a
competing approach based on backprojected SIFT keypoints. 相似文献
100.
Gump Brooks B.; Reihman Jacki; Stewart Paul; Lonky Ed; Darvill Tom 《Canadian Metallurgical Quarterly》2005,24(6):594
A number of studies have considered whether background stress affects cardiovascular responses to acute stress tasks. The present study considers the effect of a potent background stressor with a clear onset, namely the terrorist attacks on September 11, 2001. Specifically, the authors investigated differences among 9.5-year-old children tested before (N = 30) and then following (N = 20) the 9/11 attacks. In addition, a majority of these children (N = 37) were retested approximately 1 year later (i.e., before and after 9/11/2002). Children tested directly following 9/11/2001 exhibited significantly greater stroke volume and cardiac output responses to acute stress tasks compared with their responses 1 year later, and this change in reactivity differed significantly from the change in reactivity exhibited by children tested before 9/11/2001 and again 1 year later. These results suggest that a potent background stressor can temporarily heighten some children's cardiovascular responses to subsequent acute stressors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献