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1.
Research in cycling safety seeks to better understand bicycle-related crashes and injuries. The present naturalistic cycling study contributes to this research by collecting data about bicyclists’ behavior and impressions of safety–critical situations, information unavailable in traditional data sources (e.g., accident databases, observational studies). Naturalistic data were collected from 16 bicyclists (8 female; M = 39.1 years, SD = 11.4 years) who rode instrumented bicycles for two weeks. Bicyclists were instructed to report all episodes in which they felt uncomfortable while riding (subjective risk perception), even if they didn’t fall. After data collection, the bicyclists were interviewed in detail regarding their self-reported safety–critical events. Environmental conditions were also recorded via video (e.g., road surface, weather). In total, 63 safety–critical events (56 non-crashes, 7 crashes) were reported by the bicyclists, mainly due to interactions with other road users – but also due to poorly maintained infrastructure. In low-visibility conditions, vehicle-bicycle and bicycle-bicycle events were the most uncomfortable for the bicyclists. Self-reported pedestrian–bicycle events primarily consisted of pedestrians starting to cross the bicycle path without looking. With one exception, all crashes found in the study belonged to poorly maintained road and infrastructure. In particular, construction work or obstacles in the bicycle path were reported as uncomfortable and annoying by the bicyclists. This study shows how naturalistic data and bicyclists’ interviews together can provide a more informative picture of safety–critical situations experienced by the bicyclist than traditional data sources can.  相似文献   

2.
Presently, the collection and analysis of naturalistic data is the most credited method for understanding road user behavior and improving traffic safety. Such methodology was developed for motorized vehicles, such as cars and trucks, and is still largely applied to those vehicles. However, a reasonable question is whether bicycle safety can also benefit from the naturalistic methodology, once collection and analyses are properly ported from motorized vehicles to bicycles. This paper answers this question by showing that instrumented bicycles can also collect analogous naturalistic data. In addition, this paper shows how naturalistic cycling data from 16 bicyclists can be used to estimate risk while cycling. The results show that cycling near an intersection increased the risk of experiencing a critical event by four times, and by twelve times when the intersection presented some form of visual occlusion (e.g., buildings and hedges). Poor maintenance of the road increased the risk tenfold. Furthermore, the risk of experiencing a critical event was twice as large when at least one pedestrian or another bicyclist crossed the bicyclist’s trajectory. Finally, this study suggests the two most common scenarios for bicycle accidents, which result from different situations and thus require different countermeasures. The findings presented in this paper show that bicycle safety can benefit from the naturalistic methodology, which provides data able to guide development and evaluation of (intelligent) countermeasures to increase cycling safety.  相似文献   

3.
Previous research indicate that cyclists prefer safe and comfortable infrastructure. However, concepts like safety or comfort may be understood and defined in different ways by different individuals. Moreover, these concepts are so broad that it is unclear to which specific characteristics of the traffic infrastructure they are linked. Therefore, the aim of this study is to inductively examine individual evaluation criteria that cyclists use to perceive and evaluate certain route attributes. Using the Repertory Grid technique, we elicited the personal constructs of 23 participants about given route attributes and asked them to rate every attribute on every construct. The constructs were categorized and clustered resulting in five evaluation criteria, namely Mental Comfort, Physical Comfort, Interaction, Environment, and Ease of Use. Both comfort clusters were rated the most relevant for route choice, but they strengthen the suggestion of two distinct aspects of comfort, one referring to mental stress, the other referring to physical effort. Furthermore, the analyses revealed Interaction as a relatively new route criterion which also raises a new view on the negative evaluation of motor traffic and expands the concept of stress. Regarding the evaluation of route attributes, a high traffic volume and cobbled stone were rated the most negative, whereas separated cycling facilities were evaluated as most positive. Findings of this study expand existing research by qualitative insights and provide a more detailed understanding of route criteria like comfort or safety. This can be used to enhance cycling facilities and to offer preferable infrastructure for cyclists.  相似文献   

4.
Grunze HC 《CNS spectrums》2008,13(9):790-795
Antidepressants constitute a central cornerstone in the treatment of depressive syndromes. In bipolar patients, however, there is an ongoing controversy about their usefulness for at least 3 decades. Early reports, mainly concerning tricyclic antidepressants, have repeatedly pointed toward unfavorable side effects on the course of the disorder, namely switching into (hypo)mania, induction of rapid cycling, and increased risk of suicide. Most evidence for both unfavorable and favorable effects has been deducted, thus far, from small studies with methodological flaws. More substantiated evidence only recently became available. From this it appears that, at least, the switch risk, and perhaps also the risk for rapid cycling and new-onset suicidality have been overinterpreted. At the same time, these new data raise doubt about the efficacy of antidepressants as a primary-treatment choice in bipolar depression.  相似文献   

5.
Cycling has the potential to address a number of personal and societal challenges, not least with respect to health and the need for more sustainable modes of transport. However, the best way(s) to promote cycling is still unclear. In an effort to answer this question, we identified 39 interventions designed to promote cycling, with a total sample of 46,102 participants. Random effects meta-analysis estimated a small but statistically significant effect of interventions on cycling behaviour (g+ = 0.14, 95% CI [0.05, 0.23]). To identify the most effective intervention strategies, we coded the behaviour change techniques used within each of the interventions. Interventions that prompted people to self-monitor their behaviour or added objects to the environment (e.g., provided shared bikes) were more effective than those that did not use these strategies. Interventions that restructured the physical environment (e.g., built new cycle paths) were less effective than the studies that did not do this. We also identified a number of factors that moderated the effect of the interventions on outcomes; specifically, interventions that targeted a specific group, used objective measures of cycling such as accelerometers, and that were tested using independent groups designs typically yielded stronger effects. The findings should help to guide interventions to promote cycling in the future.  相似文献   

6.
ObjectiveThe present study examined changes in sport supporters' psychological momentum (PM) during a simulated cycling competition through the lens of the dynamical systems approach.DesignParticipants were asked to support one of two competing cyclists involved in a race that was displayed on a screen in a lecture hall.MethodThe race scenario was manipulated so that the image of the supported cyclist underwent either positive or negative momentum. At regular intervals, participants indicated their PM perceptions during the race.ResultsPM perceptions rapidly changed at the onset of both the positive and negative momentum sequences and then remained stable, reflecting negative hysteresis. Supporters tended to anticipate the future performance of a given athlete on the basis of their current performance. Moreover, this anticipatory tendency was stronger during the positive momentum sequence than during the negative momentum sequence.ConclusionThese results provide initial insights into how PM perceptions of sport supporters change during a competition.  相似文献   

7.
As cities make concerted efforts to become more bicycle-friendly through policy changes and infrastructure, it is important that such efforts ultimately support people who currently bicycle and remove barriers that may prevent more people from bicycling. Travel surveys can reveal the nature and distribution of bicycling trips, but perceptions and behaviours of bicyclists are better understood through qualitative methods. In particular, developing cycling cities are unique settings to examine how the built environment supports bicycling as changes are made to increase bicycling levels. Through semi-structured interviews, this research explores the case of Hamilton, Ontario and the factors that influence route choice from the perspective of regular bicyclists. Major themes were identified using thematic analysis: (i) exclusion from road space; (ii) infrastructure; and (iii) streetscape. Bicyclists highly value infrastructure and seek routes that minimize interactions with cars, while avoiding many arterial roads that prioritize motorists. Routes that appear to be more human-oriented or that have nature are also attractive. Many regular bicyclists report that current bicycle infrastructure does not meet their preferences. Despite building nearly half of the planned infrastructure network, our findings suggest the built environment is not perceived to be oriented to bicycling. This study provides policy and practice recommendations for developing cycling cities in North America as they transition towards established cycling cities.  相似文献   

8.
It has been suggested that the safety benefits of bicycle helmets are limited by risk compensation. The current study contributes to explaining whether the potential safety effects of bicycle helmets are reduced by cyclists’ tendency to cycle faster when wearing them (as a result of risk compensation), and if this potential reduction can be associated with a change in perceived risk. A previous study (Fyhri & Phillips, 2013) showed that non-routine helmet users did not increase their speed immediately after being given a helmet to wear, while routine helmet users cycled more slowly. The current study tests whether the previously found reduction in speed in response to helmet removal – as an indirect indicator of risk compensation – could be established in non-routine helmet users, after a period of habituation while cycling with a helmet.We did this by conducting a randomized crossover trial, in which we used GPS-derived speed calculations and self-reported risk perception. To test the effect of habituation, we used a design where each participant took part in two rounds with a break between and each round having two trips. We collected the data in June 2015. Non-routine helmet users (N = 31) were recruited in the field (along cycle routes in Oslo), and through a sample drawn from the Falck National register of bicycle owners. In the first phase of the study, all participants were asked to complete a test route (2.4 km downhill) with and without a helmet. In the second phase of the experiment, conducted after 1.5–2 h, the same participants again completed the test route with and without a helmet. In the time between the first and second phases of the experiment, all participants were given helmets, and told to use them on a predefined bicycle route.Habituation to the helmet between the first and second phases of the experiment did not produce any decrease (with helmet removal) in speed, on top of the habituation that occurred while cycling down the hill (the order effect). Mean speed difference for cycling with/without a helmet before the break was −0.76 km/h, after the break this difference was 0.32 km/h; 95% CIs [−0.5, 2.9] and [−0.9, 1.5]. We argue that risk compensation is an unlikely effect of using a bicycle helmet, and probably cannot explain any adverse effects related to helmet legislation.  相似文献   

9.
ABSTRACT— There is substantial evidence that males are more variable than females in general intelligence. In recent years, researchers have presented this as a reason that, although there is little, if any, mean sex difference in general intelligence, males tend to be overrepresented at both ends of its overall distribution. Part of the explanation could be the presence of genes on the X chromosome related both to syndromal disorders involving mental retardation and to population variation in general intelligence occurring normally. Genes on the X chromosome appear overrepresented among genes with known involvement in mental retardation, which is consistent with a model we developed of the population distribution of general intelligence as a mixture of two normal distributions. Using this model, we explored the expected ratios of males to females at various points in the distribution and estimated the proportion of variance in general intelligence potentially due to genes on the X chromosome. These estimates provide clues to the extent to which biologically based sex differences could be manifested in the environment as sex differences in displayed intellectual abilities. We discuss these observations in the context of sex differences in specific cognitive abilities and evolutionary theories of sexual selection.  相似文献   

10.
Three experiments explored whether response mode differences in perspective taking result from different spatial representations or different retrieval processes. Participants learned object locations and then, while blindfolded, pointed to or verbally described object locations from perspectives aligned or misaligned with their facing direction and aligned or misaligned with the learning perspective. Pointing was facilitated from the perspective aligned with the body during testing. Similar facilitation occurred when verbally labeling, but only when conducted in the context of pointing (e.g., after pointing). Without this pointing context, or after third-person strategy instructions, the effect of body alignment was eliminated for verbal responses. Pointing was less responsive to context and strategy. Across all conditions, performance was facilitated for the learning perspective. Taken together, these experiments indicate that response mode differences are due to differences in the retrieval process, which varies with strategy, rather than differences in the organization of the underlying spatial memory.  相似文献   

11.
The paper discusses what the author calls “The seduction by the father”. It would occur when, in the Oedipus complex, the father reverses his role: instead of being the one who castrates, he seduces. Seduction here is understood in the sense that he does not act as the one who imposes limits to the child. Consequently the child can not project his hostile impulses onto the father.

Based on clinical data, the Author says that, in the male child, the seduction by the father hampers the transformation of the two Oedipal attitudes towards the father into identifications. The consequences of this fact upon the construction of the “nostalgia of the father's protection” are discussed, so as the transformation of this father into the symbolic father.  相似文献   

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13.
Many current models of memory are specified with enough detail to make predictions about patterns of errors in memory tasks. However, there are often not enough empirical data available to test these predictions. We report two experiments that examine the relative frequency of fill‐in and infill errors. In immediate serial recall tasks, subjects sometimes incorrectly recall item N too soon, placing it in position N?1. The error of interest is which item is recalled after this initial mistake. A fill‐in error is the tendency to recall item N?1 next, whereas an infill error is the tendency to recall item N+1 next. Both experiments reveal more fill‐in than infill errors, not only overall but at each possible error location throughout the list. The overall ratio is approximately 2:1. We conclude that none of the currently existing models adequately accounts for fill‐in and infill errors.  相似文献   

14.
Secular-believers, who constitute about 25% of Israeli Jews, are self-identified secular people who believe in some kind of divinity. Based on in-depth interviews with secular-believer women, this study aims to reveal their theological assumptions and claims. It examines metaphors and images participants used to relate to the divine as well as the theological categories they emphasized. The study uncovers the pluralistic nature of secular-believers’ beliefs and the common tendency to address faith-related content in a positive light.  相似文献   

15.
Transition theory posits that autobiographical memories are organized by major life transitions, which is often supported by the Living-in-History effect that occurs when people frequently refer to public events to support their date estimates of personal events. In the present study, 52 Chinese older adults in Hong Kong recalled autobiographical events using cue-word method and justified the date estimates of the events. They also reported the most important events and assessed their impacts. Results showed that participants referred to public events only when estimating the date of 5.5% of word-cued events and reported a few public events as personally important, suggesting an absence of the Living-in-History effect. Nonetheless, word-cued events and important events accumulated around major life transitions to form a transition bump; the material change that important events brought about predicted whether the important events were used to organize autobiographical memory, thereby providing new evidence for the transition theory.  相似文献   

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Aiming movements to defined target positions were performed as fast and as accurately as possible by younger and older subjects and by patients in the early stages of Parkinson's disease (PD). Movement time and accuracy were tested in two conditions: with and without a centre cue. Older subjects exhibited slower movement time relative to the younger subjects only when the centre cue was present suggesting inefficient feedback processing. The performance of patients with PD was found to be as precise as that of older subjects. The movements of PD subjects, however, were slower in both conditions. Finally, the performance of subjects improved over trials. The data suggest that there is no difference in the nature of the control processes used by older and early-stage PD subjects, but that there is a reduction in the speed of these processes in PD.  相似文献   

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20.
Gila Sher 《Synthese》2011,181(2):353-365
The paper presents an outline of a unified answer to five questions concerning logic: (1) Is logic in the mind or in the world? (2) Does logic need a foundation? What is the main obstacle to a foundation for logic? Can it be overcome? (3) How does logic work? What does logical form represent? Are logical constants referential? (4) Is there a criterion of logicality? (5) What is the relation between logic and mathematics?  相似文献   

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