Application of nanofiltration processes to fluoride removal from groundwaters in the Chiang Mai Basin

The highly concentrated fluoride in groundwater has been observed in the confined aquifers of the alluvial sediments in the Chiang Mai Basin. Nanofiltration process was applied to the control of fluoride exposure to the local residents, who have suffered from serious dental and osteal fluorosis. The membrane plants used polyamide nanofilters, which were found to have different fluoride removal rates depending on pH of feed waters. Although fluoride removal rates were high at neutral to basic pH, calcium carbonate scale on the membrane surface was estimated to be the major problem in membrane fouling. Optimum combination of pretreatment in the membrane plant was evaluated through the investigation on the groundwater quality and the operational conditions

Safety of the Japanese K-Car in a Real-World Low-Severity Frontal Collision

<div><p><b>Objective:</b> Kei-cars (K-cars), which are a tiny 660 cc mini-car class 3.4 m long or less, 1.48 m wide or less, and 2.00 m high or less, have become popular in Japan. To evaluate the safety of K-car drivers in frontal collisions, we retrospectively compared the severity of injuries suffered by drivers between K-cars and standard vehicles involved in frontal collisions in which at least one injury occurred.</p><p><b>Materials and Methods:</b> From in-depth data provided by the Institute for Traffic Accident Research and Data Analysis from 1993 to 2010, records for 1379 drivers aged 36.8 ± 15.6 years were collected for analysis.</p><p><b>Results:</b> Of the 1379 drivers, 1115 subjects were in standard vehicles and 264 were in K-cars. The mean delta <i>V</i> of the struck vehicle was 28.6 ± 15.6 km/h. After classifying the subjects according to seat belt use and air bag deployment, the background of the drivers and delta <i>V</i>, the injury severity scores (ISSs) and Abbreviated Injury Scale (AIS) scores were compared for all body regions. Under similar conditions, no significant differences in severity of injuries of the drivers were found between K-cars and standard vehicles.</p><p><b>Conclusions:</b> Although we are generally concerned that drivers of small vehicles suffer more severe injuries, our results suggest that, for real-world accidents, K-cars provide similar safety for drivers involved in frontal collisions as standard vehicles in low delta <i>V</i> impact conditions.</p></div

Effectiveness of wearing a bicycle helmet for impacts against the front of a vehicle and the road surface

<p><b>Objective:</b> To assess the effect of wearing a bicycle helmet using an adult headform in terms of the head injury criterion (HIC) when the frontal and lateral parts of the helmet impact a vehicle body and also when the frontal part of the helmet impacts the road surface.</p> <p><b>Methods:</b> The adult headform was made to impact the hood, windscreen, roof top, and roof side rail of a vehicle body at an impact velocity of 35 km/h, which is a common head-to-vehicle impact velocity in real-world cyclist–vehicle collisions, in which the vehicle impacts the cyclist at 40 km/h. For the road surface impact experiments, we set a drop height of 1.5 m (impact velocity of 20 km/h).</p> <p><b>Results:</b> Helmet usage helped to reduce the HIC when the frontal and lateral parts of the helmet impacted vehicle parts other than the hood. The HIC reduction for the frontal impact was greater than that for the lateral impact. Moreover, the higher the stiffness index of the vehicle structure, the greater was the HIC reduction. However, helmet usage was ineffective for reducing skull fracture risk (HIC 2558) when the lateral part of the helmet impacted stiffer parts of the vehicle, such as the roof side rail close to the B-pillar. Helmet usage helped to reduce the HIC by 91% when the frontal part of the helmet impacted the road surface.</p> <p><b>Conclusions:</b> Wearing a helmet reduces skull fracture risk when the frontal and lateral parts of the helmet impact vehicle parts (excluding the hood) at 35 km/h and the road surface at 20 km/h. However, when the lateral part of the helmet impacts the B-pillar, the helmet cannot effectively reduce the skull fracture risk at these real-world velocities.</p

Effect on cycling behavior at a signalized intersection by fixed-point camera observation

This article is part of the Proceedings of the 6th Annual International Cycling Safety Conference held in Davis, California, USA on September 20th through 23rd in the year 2017.<br><br>Paper ID: 11