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171.
172.
In the last five decades, cognitive scientists and the psychologists of reasoning have dedicated a lot of effort designing usable traffic signs. This study investigated the interference effect produced by the position of the sign elements in traffic signage on response accuracy and reaction time. Sixteen drivers performed a flanker interference reaction time task. Incongruent graphical/space solutions, actually used for the airport stack-type sign, lead to increased reaction time and a reduction in the proportion of correct answers. These results suggest that incongruent visual information should be avoided, as this might impair drivers’ performance. These findings provide important information for the specification of future signage design guidelines and for improving road safety.  相似文献   
173.
ObjectivesThe existence of exercise addiction has been examined in numerous studies. However, none of the measures developed for exercise addiction assessment have been validated on representative samples. Furthermore, estimates of exercise addiction prevalence in the general population are not available. The objective of the present study was to validate the Exercise Addiction Inventory (EAI; Terry, Szabo, & Griffiths, 2004), and the Exercise Dependence Scale (EDS; Hausenblas & Downs, 2002b), and to estimate the prevalence of exercise addiction in general population.DesignExercise addiction was assessed within the framework of the National Survey on Addiction Problems in Hungary (NSAPH), a national representative study for the population aged 18–64 years (N = 2710).Method474 people in the sample (57% males; mean age 33.2 years) who reported to exercise at least once a week were asked to complete the two questionnaires (EAI, EDS).ResultsConfirmatory Factor Analysis (CFA) indicated good fit both in the case of EAI (CFI = 0.971; TLI = 0.952; RMSEA = 0.052) and EDS (CFI = 0.938; TLI = 0.922; RMSEA = 0.049); and confirmed the factor structure of the two scales. The correlation between the two measures was high (r = 0.79). Results showed that 6.2% (EDS) and 10.1% (EAI) of the population were characterized as nondependent-symptomatic exercisers, while the proportion of the at-risk exercisers were 0.3% and 0.5%, respectively.ConclusionsBoth EAI and EDS proved to be a reliable assessment tool for exercise addiction, a phenomenon that is present in the 0.3–0.5% of the adult general population.  相似文献   
174.
Sustained treatment attendance has been reported to be poor in publicly funded community-based clinic settings serving children and families. Several child and family characteristics have been shown to predict attendance in community-based care, but virtually no research has been conducted to examine how experiences in care, including psychotherapists' within-session practices, influence client attendance. The goal of this exploratory study was to examine how observed practice within sessions, in particular the extent to which therapists delivered elements consistent with evidence-based practices, impacts total number of sessions attended, while accounting for an array of other potential predictors. Participants include 181 children ages 4-13 and their parents entering a new episode of care for disruptive behavior problems in publicly funded clinics. Data sources include administrative billing records on treatment attendance; coded videotaped treatment sessions; and self-reports from children, parents, and therapists. Results indicate that parent education, service funding source, parent alliance with therapist, and therapist experience predicted number of sessions attended; intensity of evidence-based treatment techniques delivered to children was marginally associated with attendance (p = .059). Implications for improving engagement in community-based care are discussed.  相似文献   
175.
Monocular approaches to simultaneous localization and mapping (SLAM) have recently addressed with success the challenging problem of the fast computation of dense reconstructions from a single, moving camera. Thus, if these approaches initially relied on the detection of a reduced set of interest points to estimate the camera position and the map, they are currently able to reconstruct dense maps from a handheld camera while the camera coordinates are simultaneously computed. However, these maps of 3-dimensional points usually remain meaningless, that is, with no memorable items and without providing a way of encoding spatial relationships between objects and paths. In humans and mobile robotics, landmarks play a key role in the internalization of a spatial representation of an environment. They are memorable cues that can serve to define a region of the space or the location of other objects. In a topological representation of the space, landmarks can be identified and located according to its structural, perceptive or semantic significance and distinctiveness. But on the other hand, landmarks may be difficult to be located in a metric representation of the space. Restricted to the domain of visual landmarks, this work describes an approach where the map resulting from a point-based, monocular SLAM is annotated with the semantic information provided by a set of distinguished landmarks. Both features are obtained from the image. Hence, they can be linked by associating to each landmark all those point-based features that are superimposed to the landmark in a given image (key-frame). Visual landmarks will be obtained by means of an object-based, bottom-up attention mechanism, which will extract from the image a set of proto-objects. These proto-objects could not be always associated with natural objects, but they will typically constitute significant parts of these scene objects and can be appropriately annotated with semantic information. Moreover, they will be affine covariant regions, that is, they will be invariant to affine transformation, being detected under different viewing conditions (view-point angle, rotation, scale, etc.). Monocular SLAM will be solved using the accurate parallel tracking and mapping (PTAM) framework by Klein and Murray in Proceedings of IEEE/ACM international symposium on mixed and augmented reality, 2007.  相似文献   
176.
Recent studies on the conceptualization of abstract concepts suggest that the concept of time is represented along a left-right horizontal axis, such that left-to-right readers represent past on the left and future on the right. Although it has been demonstrated with strong consistency that the localization (left or right) of visual stimuli could modulate temporal judgments, results obtained with auditory stimuli are more puzzling, with both failures and successes at finding the effect in the literature. The present study supports an account based on the relative relevance of visual versus auditory-spatial information in the creation of a frame of reference to map time: The auditory location of words interacted with their temporal meaning only when auditory information was made more relevant than visual spatial information by blindfolding participants.  相似文献   
177.
Despite Skinner's (1957) assertion that verbal operants are initially functionally independent, recent studies have suggested that in some cases the acquisition of one verbal operant (e.g., mand) gives rise to the other (e.g., tact) without explicit training. The present study aimed to evaluate the functional independence of mands and tacts during instruction with children with autism. Four boys with autism (3 to 6 years old) were taught to construct two 4‐piece structures. Two participants were taught directly to mand, whereas the other 2 were taught to tact the names of the pieces. The effects of training were evaluated in a multiple probe design across verbal operants and tasks. Three of the 4 participants demonstrated an immediate transfer of control from 1 verbal operant to the other. These results were consistent with previous research with typically developing young children.  相似文献   
178.
Three studies examined how the use of the present versus the past tense in recalling a past experience influences behavioral intentions. Experiment 1 revealed a stronger influence of past behaviors on drinking intentions when participants self-reported an episode of excessive drinking using the present tense. Correspondingly, there was a stronger influence of attitudes towards excessive drinking when participants self-reported the episode in the past tense. Experiments 2 and 3 liked this effect to changes in construal level (Liberman, Trope, & Stephan, 2007; Trope & Liberman, 2003), with the present tense being similar to a concrete construal level and the past tense being similar to an abstract construal level.  相似文献   
179.
This article finds that, when faced with racial inequity framed as White advantage, Whites' desire to think well of their racial group increases their support for policies perceived to harm Whites. Across 4 studies, the article provides evidence that (a) relative to minority disadvantage, White advantage increases Whites' support for policies perceived to reduce their group's economic opportunities, but does not increase support for policies perceived to increase minority opportunities; and (b) the effect of White advantage on Whites' esteem for their ingroup drives the effect of inequity frame on support for policies perceived to reduce Whites' opportunities.  相似文献   
180.
We propose a new class of multiple contraction operations — the system of spheres-based multiple contractions — which are a generalization of Grove’s system of spheres-based (singleton) contractions to the case of contractions by (possibly non-singleton) sets of sentences. Furthermore, we show that this new class of functions is a subclass of the class of the partial meet multiple contractions.  相似文献   
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