Objective: The objective of this study was to estimate the safety benefits of in vehicle lane departure warning (LDW) and lane keeping aid (LKA) systems in reducing relevant real-world passenger car injury crashes.
Methods: The study used an induced exposure method, where LDW/LKA-sensitive and nonsensitive crashes were compared for Volvo passenger cars equipped with and without LDW/LKA systems. These crashes were matched by car make, model, model year, and technical equipment; that is, low-speed autonomous emergency braking (AEB) called City Safety (CS). The data were extracted from the Swedish Traffic Accident Data Acquisition database (STRADA) and consisted of 1,853 driver injury crashes that involved 146 LDW-equipped cars, 11 LKA-equipped cars, and 1,696 cars without LDW/LKA systems.
Results: The analysis showed a positive effect of the LDW/LKA systems in reducing lane departure crashes. The LDW/LKA systems were estimated to reduce head-on and single-vehicle injury crashes on Swedish roads with speed limits between 70 and 120 km/h and with dry or wet road surfaces (i.e., not covered by ice or snow) by 53% with a lower limit of 11% (95% confidence interval [CI]). This reduction corresponded to a reduction of 30% with a lower limit of 6% (95% CI) for all head-on and single-vehicle driver injury crashes (including all speed limits and all road surface conditions).
Conclusions: LDW/LKA systems were estimated to lower the driver injury risk in crash types that the systems are designed to prevent; that is, head-on and single-vehicle crashes. Though these are important findings, they were based on a small data set. Therefore, further research is desirable to evaluate the effectiveness of LDW/LKA systems under real-world conditions and to differentiate the effectiveness between technical solutions (i.e., LDW and LKA) proposed by different manufacturers. 相似文献
State of the environment reporting (SoER) is a well-established and widely applied environmental management tool in the South African context. Despite a wealth of knowledge about conducting and preparing SoERs, there is a paucity of research on the effect SoER has had on decision-making at the local government sphere. This study investigated the effect of SoER on decision-making for a sample of municipalities in the Gauteng Province of South Africa. The methodology relied on interviews with key role players, which include the ‘‘environmental function’' as well as ‘‘other functions’' responsible for infrastructure development and planning within the municipalities. The results show that notwithstanding the extensive time and resources spent on SoER, it appears to have had a limited effect on decision-making, especially beyond the environmental function. Recommendations to improve the influence of SoER on decision-making in developing countries include improved clarity on the purpose and home of SoER within municipalities, adequate budget and capacity, and effective cooperative governance both within the municipalities, and with other spheres of government. 相似文献
Large scale rainwater harvesting (LSRWH) is a promising alternative to address security and flood issues in urban areas. The development and planning of a LSRWH for an eco-community involves comprehensive site-planning, systems planning and design, which includes the rainwater source collection (roof) to the storage tank, the distribution and allocation system. This paper describes a new technique for designing a LSRWH for a community of 200 houses with an average of 4 persons per house and an average total daily water demand of 160 m3. It was found that the optimal size storage tank for a 20,000 m2 roof area is 160 m3 with a 60% reliability. The application of this model to the case study revealed a significant water saving up to 58% .The total cost for this system is 443,861 USD over a life-span of 25 years. 相似文献