Parents' views of teen driving risks, the role of parents, and how they plan to manage the risks

PROBLEM: There is limited information about how parents view teen driving risks and intend to handle these risks during the licensing process, and how they will respond to graduated licensing provisions. METHODS: Parents in Connecticut were interviewed when their teens got their learner's permit. The survey was undertaken when the state did not have a midnight restriction or a passenger restriction. RESULTS: Generally, parents were well aware of teen driving risks, thought parents should be thoroughly involved in the licensing process, and plan to be active participants themselves. DISCUSSION: Parents were concerned about the risk of driving after midnight and already restrict that behavior. However, parents do not seem to see or understand the risks of having even one teen passenger in the vehicle. IMPACT ON INDUSTRY: The views and existing practices of parents need to be taken into account in deciding on the provisions of graduated licensing legislation and how to best ensure acceptance and compliance.     

Characteristics of speeders

OBJECTIVE: To determine the characteristics of speeders, defined as drivers of vehicles traveling at least 15 mph above the posted speed limit and relatively faster than surrounding vehicles. METHODS: Vehicle speeds were recorded on 13 roads in Virginia with speed limits ranging from 40 to 55 mph. Speeders were compared with slower drivers, defined as drivers of adjacent vehicles traveling no more than 5 mph above the speed limit. License plates were used to identify vehicle owners; owners were inferred to have been driving if observed gender and estimated age matched those of the registered owner. For these drivers, information on exact driver age and gender, vehicle make and model, and driving record was obtained from the Virginia Department of Motor Vehicles. RESULTS: Five percent of the vehicles observed were traveling at least 15 mph above the limit, and 3% qualified as speeders, as defined in this study. Speeders were younger than drivers in the comparison group, drove newer vehicles, and had more speeding violations and other moving violations on their records. They also had 60% more crashes. DISCUSSION: Speeders are a high-risk group. Their speeding behavior is not likely to be controlled without vigorous, consistent enforcement, including the use of automated technology.     

Integrated Estimation of the Effect of Physical Factors on Human Functional State During Mental Work

The purpose of this study was to develop a model for an integrated estimation of the functional state of the human organism (FSHO) and an integral estimation of physical factors (PF) for hygienic rating. Tests were performed twice with 3 men in 0.7-clo clothing during 4-hr mental work with 9 combinations of 4 PF: wideband noise (55–83 dB(A)), whole-body vibration (6 Hz, a_z = 0.2–1.8 ms^?2), air temperature (18–30 °C), and illumination (1, 3, 5 lx). Thermoregulatory, cardiovascular, and psychophysiological reactions and temporary threshold of hearing (TTS₂) shifts were studied. For the integral estimation of PF influence on FSHO the model F(y₁, y₂, ... y_m) = f(x₁, x₂, ... x_n) was used, relating both FSHO and PF sets. The most important physiological parameters in creating FSHO are defined and the contribution of individual parameters of FSHO and PF is found.     

Two-phase jet releases,droplet dispersion and rainout,II. Rainout experiments

This paper describes the results of the first experimental stage of Phase IV of a Joint Industry Project (JIP) on liquid jets and two-phase droplet dispersion. The objective of this stage of the JIP was to generate experimental rainout data for non-flashing water and xylene experiments. See the overview companion paper I for a wider overview of the problem, model implementation and associated model validation.A range of orifice sizes (2.5 and 5 mm) and stagnation pressures (4–16 barg) were applied. Measurements included flow rate, initial droplet size, plume concentrations/temperatures for a range of downstream locations, and distributed rainout.Instead of the Phase Doppler Anemometry method used for droplet size measurements earlier in the JIP, a photographic technique was applied in an attempt to include measurement of the larger (non-spherical) droplets. This enabled a more accurate evaluation of the initial droplet size distribution and a much clearer understanding of the droplet morphology. The results showed that the droplet behaviour in the jet is more complex than had been anticipated with the mass distribution dominated by a very small number of large non-spherical droplets. Consequently a large number of spray images were required to evaluate an accurate size distribution.Distributed rainout was measured by weighing the amount of rainout in trays positioned along the jet direction. The rainout results showed a good degree of repeatability and internal consistency. They indicated that an increasing proportion of the released material did not rainout for increasing pressure. Rainout distance also increased with increasing pressure. Evaporation of the liquid was confirmed by temperature measurements, which showed the effect of evaporative cooling.Xylene concentration measurements (up to 1%) were carried out using a direct reading photoionization detector calibrated for xylene (measuring vapour only). For a limited dataset, the accuracy of these measurements was estimated by means of comparison against an alternative more time-consuming concentration method (xylene absorption onto a charcoal filter; measuring both vapour and liquid). The concentration measurements displayed several consistent qualitative features. For example, at a given downstream distance, the peak concentration increases with increasing pressure and nozzle diameter and the vertical height at which the peak is achieved increases. The cross-stream profiles displayed a consistent tendency to increased concentration at the edge of the jet, and the reason for this has not been established.Finally recommendations are provided for potential future work.     

Experimental determination of dust cloud deflagration parameters of selected hydrogen storage materials: Complex metal hydrides,chemical hydrides,and adsorbents

This paper discusses the results of an experimental program carried out to determine dust cloud deflagration parameters of selected solid-state hydrogen storage materials, including complex metal hydrides (sodium alanate and lithium borohydride/magnesium hydride mixture), chemical hydrides (alane and ammonia borane) and activated carbon (Maxsorb, AX-21). The measured parameters include maximum deflagration pressure rise, maximum rate of pressure rise, minimum ignition temperature, minimum ignition energy and minimum explosible concentration. The calculated explosion indexes include volume-normalized maximum rate of pressure rise (K_St), explosion severity (ES) and ignition sensitivity (IS). The deflagration parameters of Pittsburgh seam coal dust and Lycopodium spores (reference materials) are also measured. The results show that activated carbon is the safest hydrogen storage media among the examined materials. Ammonia borane is unsafe to use because of the high explosibility of its dust. The core insights of this contribution are useful for quantifying the risks associated with use of these materials for on-board systems in light-duty fuel cell-powered vehicles and for supporting the development of hydrogen safety codes and standards. These insights are also critical for designing adequate safety features such as explosion relief venting and isolation devices and for supplementing missing data in materials safety data sheets.     

An approach for domino effect reduction based on optimal layouts

An approach to reduce the probability of producing a domino effect in process industry is developed in this work. It is assumed that optimal layouts should include appropriate analysis to reduce risk during the process design stage. The model developed for this approach combines the estimation of probability of damage due to overpressure, proposed by Mingguang and Juncheng (2008), and escalation threshold values defined by Cozzani, Gubinelli, and Salzano (2006). These equations are combined with other typical layout constraints as well as bounding the probability constraint, which has resulted in a highly non-linear MINLP problem. Solving a case study used by other authors provides evidence for reliability of the developed approach. In this way, layouts are designed to reduce the escalation probability yielding safe distributions.     

A new integrated treatment for the reduction of organic and nitrogen loads in methanogenic landfill leachates

Because of their high organic and nitrogen loads and the presence of toxic and phytotoxic compounds, methanogenic landfill leachates are not easily biodegradable; therefore, direct biological treatment of these wastewaters in conventional treatment plants is not recommended.In the present paper, we report the results of an experimental investigation conducted with the aim of defining an innovative integrated process that is low in cost and easily manageable and that is able to substantially improve the characteristics of methanogenic leachates.Thus, an initial oxidation process was developed using hydrogen peroxide without a catalyst, which, operating under ambient conditions, reduces the phytotoxic compound content to 10% of the initial level, reduces the COD (chemical oxygen demand) content by 50% and increases the rapidly biodegradable substrate content by 50%. Next, nitrogen removal is accomplished by means of struvite precipitation using seawater bittern and bone meal as sources of magnesium and phosphorus, respectively, with this process, abatements were reached of approximately 90% of the ammonia nitrogen, which was recovered as struvite powder.     

Experimental and theoretical investigations for mitigating NaAlH4 reactivity risks during postulated accident scenarios involving exposure to air or water

Experimental and theoretical studies were conducted to investigate the pyrophoricity and water-reactivity risks associated with employing sodium alanate (NaAlH₄) complex metal hydride in on-board vehicular hydrogen (H₂) storage systems. The ignition and explosivity of NaAlH₄ upon exposure to oxidizers in air or water were attributed to the spontaneous formation of stable hydroperoxyl intermediates on the NaAlH₄ surface and/or H₂ production, as well as the large driving force for NaAlH₄ conversion to favorable hydroxide products predicted by atomic and thermodynamic modeling. The major products from NaAlH₄ exposure to air: NaAl(OH)₄, gibbsite and bayerite Al(OH)₃, and Na₂CO₃ observed by XRD, were identified to be formed by surface-controlled reactions. The reactivity risks were significantly minimized, without compromising de-/re-hydrogenation cyclability, by compacting NaAlH₄ powder into wafers to reduce the available surface area. These core findings are of significance to risk mitigation and H₂ safety code and standard development for the safe use of NaAlH₄ for on-board H₂ storage in light-duty vehicles.     

Fuzzy AHP-based study of cleaner production implementation in Taiwan PWB manufacturer

In recent years, many electronic manufacturing firms have looked upon Cleaner Production (CP) as the means by which they could maintain environmental practice and competitive advantages. CP has been adopted by companies as an important factor in enhancing industrial productivity. Sustainable projects that deal appropriately with environmental and social factors are also more likely to be the most profitable.This paper investigated the criteria and attributes that determine a successful adoption and implementation of CP in reference to PWB manufacture in Taiwan. Fuzzy Analytic Hierarchy Process (FAHP) methodology is used to discuss the different decision criteria that include Organizing, Systems and Technologies, Measurement and Feedback, Working environment and Worker's Culture which are all vital factors in an effective CP implementation. AHP is an efficient tool in controlling the fuzziness of the data involved in choosing the most preferred decision variables. The linguistic level of comparisons produced by the manufacturers and experts are tapped and constructed in a form of triangular fuzzy numbers in order to construct fuzzy pairwise comparison matrices. The implementation of the system is demonstrated by a problem involving three stages of hierarchy which contains different criteria and attributes at a wider perspective within an environmental uncertainty. The findings advocate that these enterprises would need to setup the priorities of the CP implementation. The results suggest a generic hierarchical model of organizations of which the highest level is to be prioritized among the CP implementation factors.