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101.
Anger and aggression among drivers in three European countries 总被引:3,自引:0,他引:3
Recent reports of 'road rage' in the British media give the impression that driver aggression is escalating. In order to understand this phenomenon we need to know what it is about driving that provokes motorists to feel anger and then to go on to express that anger in the form of aggression. A postal questionnaire survey of more than 2500 drivers was carried out in three European countries: Britain, Finland and the Netherlands. The study had three main aims: (a) to discover how angry, if at all, a range of situations on the road make drivers, (b) to find out how many drivers are likely to react aggressively to those situations, and (c) to investigate individual and/or cultural differences in terms of anger and/or aggressive responses among motorists. Results indicate that the same types of behaviour provoke anger and aggression in all three countries, and that traffic density may play a role. 相似文献
102.
Chambless Dianne L.; Floyd Frank J.; Rodebaugh Thomas L.; Steketee Gail S. 《Canadian Metallurgical Quarterly》2007,116(4):754
Patients with panic disorder with agoraphobia (n = 40) or obsessive- compulsive disorder (n = 61) participated in a 10-min problem-solving interaction with their primary relative. Relatives were categorized as hostile or nonhostile toward the patient on the basis of a measure of expressed emotion (EE). Observed interactions between patients and their hostile relatives, relative to those of dyads with a nonhostile relative, were marked by higher rates of relatives' criticism and of patients' negativity but not by higher rates of negative reciprocity. Analyses of sequences indicated that the dyads with a hostile relative had a higher rate of sequences in which the relative was first critical and the patient then negative than was the case for dyads with nonhostile relatives. Moreover, hostile relatives were more frequently critical than nonhostile relatives whether patients' preceding behavior was positive, negative, or neutral. The findings are consistent with the stress-vulnerability model of the effect of EE on mental health, in that patients living with a high EE relative appear to be exposed to higher levels of interpersonal stress. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
103.
Objective: Two studies assessed the relative contribution of affective and instrumental beliefs to the prediction of 2 risk behaviors: driving above the speed limit and smoking. Design: Both studies took the form of large-scale questionnaire surveys (Study 1, N = 292; Study 2, N = 500) measuring instrumental and affective beliefs and self-reported behavior. In both cases, behavior was also measured objectively. Outcome measures: In Study 1, speeding behavior was measured via infrared camera along sections of road with 30 mph, 40 mph, and 60 mph speed limits. Self-reports of speeding in these same contexts represented a 2nd dependent variable. In Study 2, level of smoking was measured via a carbon monoxide monitor, and participants were asked to indicate the number of cigarettes they smoked in a week. Results: In Study 1, positive and negative instrumental and affective beliefs were significant predictors of self-reported speed. The most powerful predictor was negative affective beliefs. Observed speed was predicted by negative affective beliefs only. In Study 2, the significant predictors of self-reported smoking and objective measures of smoking were positive and negative affective beliefs. Conclusion: The findings indicate the importance of affective beliefs across 2 health risk behaviors. Implications for social cognition models and interventions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
Dianne L. Poster Michele M. Schantz Stephen A. Wise 《Journal of research of the National Institute of Standards and Technology》2005,110(6):613-615
A new reference material (RM), RM 8504, has been prepared for use as a diluent oil with Aroclors in transformer oil Standard Reference Materials (SRMs) 3075 to 3080 and SRM 3090 when developing and validating methods for the determination of polychlorinated biphenyls (PCBs) as Aroclors in transformer oil or similar matrices. SRMs 3075-3080 and SRM 3090 consist of individual Aroclors in the same transformer oil that was used to prepare RM 8504. A unit of RM 8504 consists of one bottle containing approximately 100 mL of transformer oil. No additional constituents have been added to the oil. 相似文献
105.
A random PSK modulated signal generated with an optical waveguide phase modulator is used to obtain an error signal and lock the frequency of an AlGaAs semiconductor laser to the /sup 7/Rb D/sub 2/ line. The measured error signal is similar to that obtained with sinusoidal phase modulation under the same conditions. The technique could be applied to longer wavelength lasers and other types of laser that cannot be directly modulated such as fibre lasers.<> 相似文献
106.
Paxton Susan J.; Eisenberg Marla E.; Neumark-Sztainer Dianne 《Canadian Metallurgical Quarterly》2006,42(5):888
This study investigated prospective risk factors for increases in body dissatisfaction in adolescent girls and boys in the Eating Among Teens Project. At the time of first assessment (Time 1), participants were a cohort of early adolescent girls (N=440) and boys (N=366) and a cohort of middle adolescent girls (N=946) and boys (N=764). Participants were followed up 5 years later (Time 2). Potential prospective risk factors examined included body mass index, socioeconomic status, ethnicity, parent dieting environment, peer environment, and psychological factors. Predictors of Time 2 body dissatisfaction were Time 1 body dissatisfaction, body mass index, socioeconomic status, being African American, friend dieting and teasing, self-esteem, and depression. However, the profile of predictors differed across the samples. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
This paper describes a view-based method for recognizing 3D objects from 2D images. We employ an aspect-graph structure, where the aspects are not based on the singularities of visual mapping but are instead formed using a notion of shape similarity between views. Specifically, the viewing sphere is endowed with a metric of dis-similarity for each pair of views and the problem of aspect generation is viewed as a segmentation of the viewing sphere into homogeneous regions. The viewing sphere is sampled at regular (5 degree) intervals and the similarity metric is used in an iterative procedure to combine views into aspects with a prototype representing each aspect. This is done in a region-growing regime which stands in contrast to the usual edge detection styles to computing the aspect graph. The aspect growth is constrained such that two aspects of an object remain distinct under the given similarity metric. Once the database of 3D objects is organized as a set of aspects, and prototypes for these aspects for each object, unknown views of database objects are compared with the prototypes and the results are ordered by similarity. We use two similarity metrics for shape, one based on curve matching and the other based on matching shock graphs, which for a database of 64 objects and unknown views of objects from the database give a recall rate of (90.3%, 74.2%, 59.7%) and (95.2%, 69.0%, 57.5%), respectively, for the top three matches; cumulative recall rate based on the top three matches is 98% and 100%, respectively. The result of indexing unknown views of objects not in the database also produce intuitive matches. We also develop a hierarchical indexing scheme to prune unlikely objects at an early stage to improve the efficiency of indexing, resulting in savings of 35% at the top level and of 55% at the next level, cumulatively. 相似文献
108.
Tanabe M Vandermeulen GW Chan WY Cyr PW Vanderark L Rider DA Manners I 《Nature materials》2006,5(6):467-470
Living polymerizations involve the creation of polymer chains without significant irreversible chain transfer or chain termination. Such processes are widely used to access well-defined macromolecular materials with controlled architectures, such as block and star polymers. Although this concept was first realized for anionic polymerizations in the 1950s, many key recent advances have been made, most notably in the area of radical polymerization. Here, we report a living photopolymerization that involves photoexcited monomers. Exposure of metal-containing ferrocenophane monomers to Pyrex-filtered light from a mercury lamp (lambda>310 nm) or to bright sunlight in the presence of an anionic initiator leads to living polymerizations, in which the conversion and molecular weight of the resulting polymer can be controlled by the irradiation time. Photoirradiation selectively weakens the iron-cyclopentadienyl bond in the monomer, allowing the use of moderately basic and highly functional-group-tolerant initiators. The polymerization proceeds through attack of the initiator and propagating anion on the iron atom of the photoexcited monomer and, remarkably, the polymerization rate decreases with increasing temperature. Block copolymer formation is possible when the light source is alternately switched on and off in between sequential addition of different monomers, providing unprecedented, photocontrolled access to new types of functional polymers. 相似文献
109.
Semi-Automated Extraction of Rivers from Digital Imagery 总被引:3,自引:0,他引:3
The manual production of vector maps from digital imagery can be a time consuming and costly process. Developing tools to automate this task for specific features, such as roads, has become an important research topic. The purpose of this paper was to present a technique for the semi-automatic extraction of multiple pixel width river features appearing in high resolution satellite imagery. This was accomplished using a two stage, multi-resolution procedure. Initial river extraction was performed on low resolution (SPOT multi-spectral, 20 m) imagery. The results from this low resolution extraction were then refined on higher resolution (KFA1000, panchromatic, 5 m) imagery to produce a detailed outline of the channel banks. To perform low resolution extraction a cost surface was generated to represent the combined local evidence of the presence of a river feature. The local evidence of a river was evaluated based on the results of a number of simple operators. Then, with user specified start and end points for the network, rivers were extracted by performing a least cost path search across this surface using the A* algorithm. The low resolution results were transferred to the high resolution imagery as closed contours which provided an estimate of the channel banks. These contours were then fit to the channel banks using the dynamic contours (or snakes) technique. 相似文献
110.
Georges Abdul-Nour M. Selim Akturk Bernard Cyr Jocelyn R. Drolet Heng Huang 《International Journal of Flexible Manufacturing Systems》1999,11(3):315-317