1,720,971 research outputs found
Proactive Safety Evaluation of Infrastructure Designs Using Driving Simulation
No full textIn this research, the usefulness of driving simulation for studying the effects of road designs on human driving behaviour before these road designs are implemented in real life is explored. The research consists of three studies designed to address important safety issues related to human driving behaviour regarding merging on motorways, separation of express and local lanes on motorways, and horizontal curves situated in a two-way rural road. The experimentation was conducted by allowing participants to drive in a virtually created road environment in a medium fidelity driving simulator at IMOB. The results obtained from the three studies conclude that driving simulation is an economical, effective, efficient, and a safe tool for evaluation of road designs prior to their construction. Evaluating road designs in the design phase will considerably improve the level of safety of road designs. It can also highlight the possible flaws in the road design (if any) and help road designers with decision making in the road design process. The results obtained from this research promote the use of the driving simulator for evaluation of road designs so that possible social and economic losses that might result due to an unsafe road design can be avoided.Higher Education Commission (HEC) Pakista
Proactive Safety Evaluation of Infrastructure Designs Using Driving Simulation
No full textIn this research, the usefulness of driving simulation for studying the effects of road designs on human driving behaviour before these road designs are implemented in real life is explored. The research consists of three studies designed to address important safety issues related to human driving behaviour regarding merging on motorways, separation of express and local lanes on motorways, and horizontal curves situated in a two-way rural road. The experimentation was conducted by allowing participants to drive in a virtually created road environment in a medium fidelity driving simulator at IMOB. The results obtained from the three studies conclude that driving simulation is an economical, effective, efficient, and a safe tool for evaluation of road designs prior to their construction. Evaluating road designs in the design phase will considerably improve the level of safety of road designs. It can also highlight the possible flaws in the road design (if any) and help road designers with decision making in the road design process. The results obtained from this research promote the use of the driving simulator for evaluation of road designs so that possible social and economic losses that might result due to an unsafe road design can be avoided.Higher Education Commission (HEC) Pakista
Standard freeway merge designs support safer driver behaviour compared to taper designs: a driving simulator study
No full textRoad geometric design standards provide various possibilities for merging freeways with a decreasing number of lanes. In this study, an alternative design (i.e. taper design) is investigated and compared with the standard design under three different heavy vehicle compositions to understand driving performance in relation to the flow of traffic. Taper design is not always the first choice in the road geometric design guidelines and the designer has to provide arguments for selecting this design. Taper design and its comparison with other alternatives are also not well explored in literature. In this study, a driving simulator was used to examine and compare the performance of these two designs under different heavy vehicle compositions. Qualitative results showed that the perceived safety was better for the standard design compared to the taper design. Mean speed, acceleration, standard deviation of acceleration/deceleration, and cumulative lane changes were chosen as behavioural parameters to compare these two designs using MANOVA and repeated measures ANOVA. Results revealed that drivers’ discomfort in performing merging manoeuvres was greatest in case of a taper design and when the percentage of heavy vehicles was moderate (15%). Overall, the standard design was found to be more favourable.
Practitioner summary: Driving behaviour at merging freeways with a decreasing number of lanes is underexplored. We analysed safety in driving behaviour considering heavy vehicles for taper and standard designs provided in Dutch guidelines using a driving simulator. The standard design was found to be safer and the presence of moderate heavy vehicles caused more disturbances in driving behaviour.Part of this research was funded by Higher Education Commission of Pakistan (HEC)
Impact of perceptual countermeasures on driving behavior at curves using driving simulator
No full textObjective: The probability of crash occurrence on horizontal curves is 1.5 to 4 times higher than that on tangent sections. A majority of these crashes are associated with human errors. Therefore, human behavior in curves needs to be corrected.
Methodology: In this study, 2 different road marking treatments, optical circles and herringbone patterns, were used to influence driver behavior while entering a curve on a 2-lane rural road section. A driving simulator was used to perform the experiment. The simulated road sections are replicas of 2 real road sections in Flanders.
Results: Both treatments were found to reduce speed before entering the curve. However, speed reduction was more gradual when optical circles were used. A herringbone pattern had more
influence on lateral position than optical circles by forcing drivers to maintain a safe distance from opposing traffic in the adjacent lane.
Conclusion: The study concluded that among other low-cost speed reduction methods, optical circles are effective tools to reduce speed and increase drivers’ attention. Moreover, a herringbone
pattern can be used to reduce crashes on curves, mainly for head-on crashes where the main problem is inappropriate lateral position
Random forest models for motorcycle accident prediction using naturalistic driving based big data
Get PDFMotorcycle accident studies usually rely upon data collected from road accidents collected through questionnaire surveys/police reports including characteristics of motorcycle riders and contextual data such as road environment. The present study utilizes big data, in the form of vehicle trajectory patterns collected through GPS, coupled with self-reported road accident information along with motorcycle rider characteristics to predict the likelihood of involvement of a motorcyclist in an accident. Random Forest-based machine learning algorithm is employed by taking inputs based on a variety of features derived from trajectory data. These features are mobility-based features, acceleration event-based features, aggressive overtaking event-based features and motorcyclists socio-economic features. Additionally, the relative importance of features is also determined which shows that aggressive overtaking event-based features have more impact on motorcycle accidents as compared to other categories of features. The developed model is useful in identifying risky motorcyclists and implementing safety measures focused towards them
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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