Browsing by Author "Sinclair, M."

Now showing 1 - 8 of 8
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    Auditory intelligent speed adaptation for long–distance informal public transport in South Africa
    (IEEE, 2016-04) Ebot Eno Akpa, N. A.; Booysen, Marthinus J.; Sinclair, M.
    ENGLISH ABSTRACT: Informal transport refers to the collective passenger road transport industry with little or no regulatory control of its operations, usually characterised by unplanned and ad-hoc service delivery. The notoriously dangerous informal transport industry in South Africa – dominated by minibus taxis – has been shown to disregard the posted speed limit on long-distance trips. Not only do they frequently exceed the differentiated speed limit imposed on minibus taxis, but also the speed limit imposed on normal passenger vehicles. This paper evaluates the impact of an auditory Intelligent Speed Adaptation (ISA) intervention, applied at various intensity levels, on the speeding behaviour of this seemingly intransigent mode of transport. The experiment evaluates the behaviour on the R61 between Beaufort West and Aberdeen. We evaluate the speeding distributions, speeding frequencies, speed percentiles, mean speeds, and the statistical relevance of key metrics. We find that the auditory intervention has a clear impact on speeding behaviour, both when applied at an audible level that can be drowned out by a radio, and even greater impact at a loud level. The impact on speeding is significant, with speeding frequency (both time and distance) reducing by over 20 percentage points.
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    A comparative evaluation of the impact of average speed enforcement (ASE) on passenger and minibus taxi vehicle drivers on the R61 in South Africa
    (South African Institution of Civil Engineering, 2016) Akoku Ebot Eno Akpa, Nelson; Booysen, M. J.; Sinclair, M.
    Average speed enforcement (ASE) is an emergent alternative to instantaneous speed limit enforcement to improve road safety, and is used to enforce an average speed limit over a road segment. This paper presents a study on the response of passenger vehicles and minibus taxis to ASE on the R61 in South Africa. A spatio-temporal quantitative study of speed compliance was conducted, where metrics such as speed variability, average speed and 85th percentile speed measured prior to, and during enforcement, were analysed for two prominent modes of transport - passenger vehicles and minibus taxis. These measurements were taken on the enforcement route and on control routes adjacent to and further away from the enforcement route. A qualitative study was also conducted to evaluate the relationship between speed compliance and driver understanding of the system. The impact of the system on crash risk and injury severity was also examined before and during enforcement. For passenger vehicles, results showed that the introduction of ASE was followed by a reduction in mean speed on the enforcement route and adjacent control route. For minibus taxis, it was found that ASE appears to have little influence on improving speed compliance, which is likely associated with a lack of driver understanding of how the system operates.
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    The impact of average speed over distance (ASOD) systems on speeding patterns along the R61
    (2014-12-10) Ebot Eno Akpa, N. A.; Booysen, Marthinus J.; Sinclair, M.
    ENGLISH ABSTRACT: Speeding is considered to be a major contributing cause of road fatalities in Sub-Saharan Africa and South Africa in particular. The minibus taxi industry is a vibrant yet partly informal sector of public transport in South Africa, which has been associated with speed-related road fatalities. Although countermeasures have been implemented to address speeding, they have not led to significant reduction in road fatalities and adherence to legal speed limits. Among the countermeasures deployed on some highways is the Average Speed Over Distance (ASOD) system which uses cameras to enforce speed limits. In this paper, historical probe data is used to evaluate the impact of the ASOD system on speed profiles of passenger vehicles. The data also consists of speed, time and location information gathered by navigation and fleet management devices that were installed in minibus taxis. The evaluation is based on spatial differentiation (the impact on the enforcement site with ASOD versus the control site without ASOD) and time differentiation (the impact before and during ASOD enforcement). For passenger vehicles, the results show that the presence of ASOD systems caused a reduction in mean speeds and ensured compliance with speed limits at enforcement and control sites. On the other hand, the system appears to have no influence on minibus taxis, with high, yet similar average speeds measured in the enforcement and control sites during ASOD enforcement.
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    Injury severity in relation to seatbelt use in Cape Town, South Africa : a pilot study
    (Health & Medical Publishing Group, 2014-07) Van Hoving, D. J.; Hendrikse, C.; Gerber, R. J.; Sinclair, M.; Wallis, L. A.
    Background. Injuries and deaths from road traffic collisions present an enormous challenge to the South African (SA) healthcare system. The use of restraining devices is an important preventive measure. Objective. To determine the relationship between seatbelt use and injury severity in vehicle occupants involved in road traffic collisions in Cape Town, SA. Methods. A prospective cohort design was used. Occupants of vehicles involved in road traffic collisions attended to by EMS METRO Rescue were included during the 3-month data collection period. Triage categories of prehospital patients were compared between restrained and unrestrained groups. Patients transferred to hospital were followed up and injury severity scores were calculated. Disposition from the emergency centre and follow-up after 1 week were also documented and compared. Results. A total of 107 patients were included in the prehospital phase. The prevalence of seatbelt use was 25.2%. Unrestrained vehicle occupants were five times more likely to have a high triage score (odds ratio (OR) 5.4; 95% confidence interval (CI) 1.5 - 19.5). Fifty patients were transferred to study hospitals. Although seatbelt non-users were more likely to be admitted to hospital (p=0.002), they did not sustain more serious injuries (OR 0.44; 95% CI 0.02 - 8.8). Conclusion. The prevalence of seatbelt use in vehicle occupants involved in road traffic collisions was very low. The association between seatbelt non-use and injury severity calls for stricter enforcement of current seatbelt laws, together with the development and implementation of road safety interventions specifically focused on high-risk groups.
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    Interventions to promote the use of seat belts
    (Cochrane, 2014-07-24) Willems, B.; Uthman, O. A.; Sinclair, M.; Young, T.
    This is the protocol for a review and there is no abstract. The objectives are as follows: To assess the effects of interventions promoting the use of seat belts.
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    On the comparison of modern production management philosophies
    (SAIIE, 1990) Sinclair, M.
    ENGLISH ABSTRACT: A variety of production management philosophies are discussed in the literature and implemented in industry. This paper will present a framework for the comparison of such management approaches. Each of the modern production management systems MRP I, MRP II, OPT and JIT will be discussed within this framework. A comparison of these approaches will then be made.
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    Perceptions and Realities of Vehicle Speed Around Schools in Stellenbosch
    (Document Transformation Technolgies cc, 2013) Ackerman, T.; Sinclair, M.
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    Shift scheduling for a maintenance workshop
    (SAIIE, 1990) Sinclair, M.; Muller, L.
    ENGLISH ABSTRACT: A big passenger transport company experienced problems with the utilization of their maintenance crews. Large amounts of overtime were logged, while at the same time a lot of idle time was experienced. This paper describes the development on a microcomputer of a Decision Support System (DSS) to improve their shift scheduling. Central to the DSS is a heuristic algorithm which generates shift schedules. This algorithm is easy to understand and provides good results, while it solves the real life problem rapidly on a microcomputer.