Driver exposure: The indirect approach for obtaining relative measures

The induced exposure procedure is used to obtain three indices: relative exposure index, liability index and hazard index. Values of these indices are computed for the following categories: rural/urban, male/female, age (7), day/night, time of day, weekend/weekday for 1.7 million qccidents in 25 states. The liability index comparing males under 20 with males 21–24 agrees quite well with established weighting factors for an insurance group.     

Critique of Sam Peltzman's study : The effects of automobile safety regulation

The variables used in Peltzman's analysis were reviewed. It was concluded that some of them were arbitrarily chosen, that some were correlated, and that important factors were omitted. This may cause spurious and biased correlations. Peltzman's time series regression equations were reconstructed and found unstable, which makes them useless for predictions which are one basis for Peltzman's conclusions. The cross-sectional analyses were found to be unvalidated. Their results for important factors disagreed with those from the time series analysis. Peltzman's conclusions on the role of young drivers were compared with their actual accident involvement and found to disagree. To illustrate the misuse of trend models, a “model” for pedestrian deaths was constructed which leads to conclusions contradicting Peltzman's.     

Treatment of door-manufacturing factories wastewaters using CDEO and other AOPs: A comparison

In this work, three advanced oxidation technologies have been studied to improve the quality of the effluents of a physicochemical process and of a combined physicochemical–biological process during the treatment of actual industrial wastes of wooden door-manufacturing factories. From the treatment point of view (neglecting costs), advanced oxidation processes can be successfully used to treat both, coagulated and biologically treated wastes. Conductive-diamond electrochemical oxidation (CDEO) was found to be the more effective technology because it can reduce completely the chemical oxygen demand (COD) (no production of refractory compounds) with a very high current efficiency. However, from the economic viewpoint, the direct treatment of the coagulated wastes can not be recommended because it is very expensive. Only Fenton oxidation or conductive-diamond electrochemical oxidation can be cost-efficiently used to refine the quality of the effluent of the biological process.     

Sulfamethoxazole abatement by photo-Fenton: Toxicity,inhibition and biodegradability assessment of intermediates

The objective of this work was to study the abatement of 200 mg L⁻¹ sulfamethoxazole (SMX) solution by means of photo-Fenton process. Biodegradability of the treated solutions was followed by the ratio biochemical oxygen demand at five days/chemical oxygen demand (BOD₅/COD) and toxicity by Microtox^® and inhibition tests. Experiments with different initial concentration of H₂O₂ were carried out. The initial amount of Fe²⁺ and pH of the solution were set at 10 mg L⁻¹ and 2.8 respectively. The temperature of the reactor was kept constant in all the experiments (25 ± 0.8 °C). Photo-Fenton process is thought to be a successful treatment step to improve the biodegradability of wastewater containing SMX. The complete antibiotic removal was achieved for a H₂O₂ dose over 300 mg L⁻¹. Biodegradability (BOD₅/COD) rose from zero (SMX solution) to values higher than 0.3 (treated solutions). Toxicity and inhibition tests pointed out in the same direction: oxidized intermediates for initial H₂O₂ dose over 300 mg L⁻¹ showed no toxicity effects on pure bacteria and no inhibition on activated sludge activity.     

Relationships between road accidents and hourly traffic flow—II: Probabilistic approach

This is a continuation of the investigation into relationships between accident rate and hourly traffic flow as outlined in Part I of the research. The underlying study attempts to determine appropriate models for single- and multi-vehicle accident rates in conjunction with free-flow and congested-flow conditions. For the free-flow data, the total accident rate-hourly flow curve follows the U-shaped configuration. This form is the result of a convex downward and a convex upward curve for single- and multi-vehicle accidents, respectively. For the congested-flow data (characterized by multi-vehicle accidents), the accident rate increases sharply with hourly flow. The models are applied to probabilistic aspects with consideration of a fitted, generalized (hourly flow dependent) headway model. The headway model represents the probability that two vehicles which are, even instantaneously, under a car-following mode are in a potentially hazardous situation. The approach investigated is believed to provide an essential input for both simulation studies and theoretical models of road traffic accidents.