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91.
    
Due to the COVID-19 pandemic, governments imposed several mobility restrictions which can be used to evaluate their impact on air quality and generate better-targeted policies to improve it. Therefore, this study aimed to define sustainable mitigation measures to reduce air pollution based on quantifying the impacts of the restrictions imposed during the COVID-19 pandemic on air quality in Portugal. Thus, hourly concentrations of PM10, PM2.5, NO2, O3, CO and SO2 were obtained from the Portuguese Air Quality Monitoring Network. Data was then divided into six periods (2020–2021) and compared with the corresponding historical periods (2015–2019). Furthermore, the satellite data of NO2, CO, and absorbing aerosol index (AAI) from the sentinel-5P TROPOMI was collected to complement the analysis conducted for the monitoring data. Overall, air quality improved in all study periods and areas, except in industrial sites. The satellite data corroborated the results herein achieved and thus validated the real effect of the measures adopted in the country during the pandemic on air quality. Sustainable policies to improve air quality could include remote (or hybrid) work whenever possible as a long-term measure and prohibition of travelling between municipalities when an extraordinary event of high air pollution is predicted or occurs. Other policies should be adopted for industrial areas. Given this, and as the restrictive mobility measures had a strong effect on reducing air pollution, the post-COVID era represents an opportunity for society to rethink future mobility and other emerging policies, that should favour softer and cleaner means of transportation.  相似文献   
92.
93.
In order to evaluate the leading and lagging effects of process safety climate on incidents, we correlated safety climate survey data with organizational safety records from before and after the survey time period. We obtained data from a large, multinational organization with manufacturing operations involving a number of complex processes, chemicals, and hazardous substances. A total of 7728 employees from 62 sites responded to a safety climate survey in 2007. Individual responses were aggregated to the site-level and matched to site-level organizational records of process safety incidents 1 year before and 1 year after survey administration. Employees’ perceptions of good routine housekeeping were significantly related to environmental impact incidents as both a leading and a lagging indicator, as well as fires/explosions and property damage outcomes. Employees’ perceptions of systems to prevent backlogs and the extent to which health and safety problems are promptly corrected were also related to environmental releases and fires/explosions. Implications for process safety climate research, organizational survey strategies, and organizational climate change are discussed.  相似文献   
94.
Alcohol is a known risk factor for many kinds of injuries, but past research has failed to implicate alcohol intoxication as a major cause of work injuries in the U.S. Local and regional studies have indicated that alcohol-related injuries are relatively less common in work settings than non-work settings. In a six-month study, the National Electronic Injury Surveillance System collected the first national sample data on alcohol and injuries presenting to hospital emergency rooms. The study included both work injuries and product-related non-work injuries. Alcohol intoxication was ascertained by emergency room chart review. Alcohol involvement was much lower than in other studies, probably because of poor sensitivity in ascertainment, and it was 10 times lower among work injuries than non-work injuries. “Non-work activities at the time of injury” were a significant risk factor for alcohol-related injuries (odds ratio = 7). Thus, results of this national study are consistent with previous research in finding that alcohol poses a greater risk for nonwork injury than for work injury.  相似文献   
95.
Objective: The objective of this study is to use a validated finite element model of the human body and a certified model of an anthropomorphic test dummy (ATD) to evaluate the effect of simulated precrash braking on driver kinematics, restraint loads, body loads, and computed injury criteria in 4 commonly injured body regions.

Methods: The Global Human Body Models Consortium (GHBMC) 50th percentile male occupant (M50-O) and the Humanetics Hybrid III 50th percentile models were gravity settled in the driver position of a generic interior equipped with an advanced 3-point belt and driver airbag. Fifteen simulations per model (30 total) were conducted, including 4 scenarios at 3 severity levels: median, severe, and the U.S. New Car Assessment Program (U.S.-NCAP) and 3 extra per model with high-intensity braking. The 4 scenarios were no precollision system (no PCS), forward collision warning (FCW), FCW with prebraking assist (FCW+PBA), and FCW and PBA with autonomous precrash braking (FCW + PBA + PB). The baseline ΔV was 17, 34, and 56.4 kph for median, severe, and U.S.-NCAP scenarios, respectively, and were based on crash reconstructions from NASS/CDS. Pulses were then developed based on the assumed precrash systems equipped. Restraint properties and the generic pulse used were based on literature.

Results: In median crash severity cases, little to no risk (<10% risk for Abbreviated injury Scale [AIS] 3+) was found for all injury measures for both models. In the severe set of cases, little to no risk for AIS 3+ injury was also found for all injury measures. In NCAP cases, highest risk was typically found with No PCS and lowest with FCW + PBA + PB. In the higher intensity braking cases (1.0–1.4 g), head injury criterion (HIC), brain injury criterion (BrIC), and chest deflection injury measures increased with increased braking intensity. All other measures for these cases tended to decrease. The ATD also predicted and trended similar to the human body models predictions for both the median, severe, and NCAP cases. Forward excursion for both models decreased across median, severe, and NCAP cases and diverged from each other in cases above 1.0 g of braking intensity.

Conclusions: The addition of precrash systems simulated through reduced precrash speeds caused reductions in some injury criteria, whereas others (chest deflection, HIC, and BrIC) increased due to a modified occupant position. The human model and ATD models trended similarly in nearly all cases with greater risk indicated in the human model. These results suggest the need for integrated safety systems that have restraints that optimize the occupant's position during precrash braking and prior to impact.  相似文献   

96.
This paper is an empirically grounded essay about the current state of organizational behavior (OB) research and productive future directions. We report the results of a survey of OB scholars about the current importance of various research topics and their importance in an ideal world. We compare the survey responses with an archival analysis of papers published in leading OB journals over a 10‐year period. We suggest that many of the topics that our respondents perceive to be ‘under researched’ can be summarized with one particular definition of OB that emphasizes organizing behavior. Considering all three definitions together, we highlight the limitations of the traditional (Big‐B and Contextualized‐B) definitions and discuss the benefits of a more organizational (Big‐O) approach. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
97.
Soy-polyol has been synthesized via a low energy two-step continuous route thus avoiding intermediate steps and chemicals. The functional groups of soy-polyol thus produced were identified by Fourier transform infrared (FTIR) spectroscopy which confirmed the cleavage of the double bonds, the formation of new epoxy linkages and the presence of hydroxyl groups. The change in chemical structure and physical properties of the soy polyol was further characterized and the results indicated a successful conversion with reduced unsaturation, increased hydroxyl number and increased viscosity. Polyurethane foam was prepared from soy-polyol using isocyanate and thermogravimetric analysis was used to study its thermal decomposition behaviour. Multiple transitions were identified in relation to depolymerization and bond dissociation. Density and compressive strength of the soy-foam were found to be satisfactory. An investigation of microstructure of soy foam by scanning electron microscope and X-ray computed tomography revealed the internal cell morphology and cell structure.  相似文献   
98.
99.
The hawksbill sea turtle ( Eretmochelys imbricata ) is valued for its mottled shell, called bekko in Japan. Populations of hawksbills have declined worldwide, and currently there is a ban on all international trade of hawksbill shell and products (Convention on International Trade of Endangered Species of Wild Fauna and Flora). In 1992 the Bekko Association of Japan introduced a fisheries model for hawksbill sea turtles in Cuba. The model estimated a sustainable yield of 5500 turtles from Cuban feeding grounds. We examined the model to determine whether this level of harvest was reasonable. Little biological information is available for hawksbills, so the model contained a number of simplifying assumptions, and several of its parameters were unsupported by data. The population was assumed to be at equilibrium, with a constant number of recruits (1-year-old turtles) and constant annual survival and growth rates. We analyzed the model to see how population size and sustainable yield results were affected by changes in various model parameters, and we found that the model was most sensitive to annual survival probability, which was assumed to be a constant 90% per year for all turtles greater than 1 year old. When we entered growth curves generated by mark-recapture data from other hawksbill populations, the model predicted a wide range of population sizes and sustainable yields. We determined that the assumptions of the current model make it unreliable for predicting sustainable yield of hawksbills, and that much research is needed to produce a more accurate model for management of this endangered species.  相似文献   
100.
A contingent valuation survey of users of the 140 km Ridgeway National Trail was undertaken to estimate the value that users place on access to the Trail. The survey found that users had a mean willingness to pay for access to the Ridgeway of £1.24 per visit (£1.13– £1.36 95% Confidence Limits). With around 150 000 visits to the Ridgeway each year, this gives an estimated annual aggregate benefit of £186 000 (£169 500– £204 000 95% Confidence Limits) plus the economic benefits to local economies of visitor spending of some £0.8 million. This compares with the costs of Trail maintenance of around £154 000 per year. The development of National Trails in England for recreation and tourism is also discussed.  相似文献   
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