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941.
An enterprise can modify several factors that impact on the Occupational Health and Safety (OHS) performance. Within the implementation of the E-merging project (financed by INAIL, the Italian National Institute for Insurance against Occupational Accidents) – to improve safety in Small- and Medium-sized Enterprises (SMEs) – development context, a thorough literature review, supported by later practitioners’ suggestions, has been performed in order to identify the factors which can be related to the OHS issue. Then, the mutual interactions among the identified OHS-related factors and the interactions among the OHS-related factors and the OHS performance have been identified for SMEs and tested on the basis of two existing data sources, i.e. the INAIL most recent dataset and a survey carried out among SMEs in the metalworking industry. This allows to understand the root causes of some evidences, which enables entrepreneurs and managers to plan interventions for the improvement of the OHS performance.  相似文献   
942.
Airports represent highly complex organisations, incorporating such interdependent operations as airlines, ground transport, flight services, ground services, refueling, maintenance, customer services, catering, administration and security. Airports, and especially International Airports, must ensure that their operations are conducted in a safe and efficient manner, as the consequence of any error or failure during operations has the potential for catastrophic outcomes. The international governing body for air transportation, ICAO, requires that airports must implement a Safety Management System as a means of ensuring safe operations and eliminating or reducing the likelihood of low frequency/high consequence incidents. This research project sought to determine the extent to which the implementation of a Safety Management System (SMS) influenced the attitudes of airport employees toward unsafe acts. The hypothesis tested was that the implementation of an SMS into an airport will result in an improvement in attitudes toward safety. A Safety Culture Survey was utilized to measure these attitudes. Two International Airports were chosen to measure the extent to which the introduction of an SMS at one airport would influence the safety attitude and culture of those employees. Sharjah International Airport, UAE, was used as the experimental group, as it did not have a formal SMS in operation, with another English-speaking International Airport (the Second Airport) being used as a control group, as it already had an SMS in operation. A Safety Culture Survey was used as the pre and post-test measure over a 12-month period to determine the extent of influence of the introduction of the SMS at Sharjah Airport. The results of Phase 1 of the survey (June 2008) were compared against the results of Phase 2 of the survey (June 2009). The average score reported by participants at Sharjah Airport increased significantly from pre-test measure to post-test measure in relation to communication, safety rules, supportive environment, personal risk appreciation, work environment, and involvement. At the same time, the average score for personal priorities decreased significantly from Phases 1 to 2. Results indicate that participants at Sharjah Airport recorded a significant positive shift in attitude to the safety factors covered in the Safety Culture Survey, whilst at the same time responses from the Second Airport showed no such shift in attitude. The Second Airport showed neither decline nor improvement in responses. Whilst some methodological issues were identified, the results were of sufficient strength as to conclude that the outcomes reported support the hypothesis that the introduction of an SMS at Sharjah Airport has effected positive changes not observed at the Second Airport. Recommendations for ongoing research were made to further explore the strength of relationship between SMS and safety attitudes, as well as the relationship between safe attitude and safe behaviour.  相似文献   
943.
The officer of the deck (OOD) of a US Navy ship is in charge of the safe and proper operation of the ship, and accountable to the commanding officer for every event that occurs during his or her OOD watch. This paper discusses the development of a prototype behavioral marker system to evaluate, and provide feedback on, the nontechnical (cognitive, social, and personal resource) skills of OODs.An initial set of 17 categories of nontechnical skills were identified from a literature review. A focus group with four qualified OODs used the skills identified from the literature review to develop an initial taxonomy of five categories, each with two or three corresponding behavioral elements. This taxonomy was then used to classify 149 statements concerned with the nontechnical skills of OODs collected from 16 critical incident interviews. After three iterations of adaptations to the taxonomy, two independent raters were able to reach acceptable levels of reliability in using the taxonomy to classify the statements. Although further development work is required, it is suggested that the prototype behavioral marker system has implications for improving safety and performance on military and civilian ships.  相似文献   
944.
In road safety literature the effects of emotional content and salience of advertising billboards have been scarcely investigated. The main aim of this work was to uncover how affect-laden roadside advertisements can affect attention – eye-movements – and subsequent risky decisions – braking – on the Honda Riding Trainer motorcycle simulator. Results indicated that the number of fixations and total fixation time elicited by the negative and positive emotional advertisements were larger than the neutral ones. At the same time, negative pictures got later gaze disengagement than positive and neutral ones. This attentional capture results in less eye fixation times on the road relevant region, where the important driving events happen. Finally, the negative emotional valence advertisements sped up braking on subsequent risky situations. Overall results demonstrated how advertisements with emotional content modulate attention allocation and driving decisions in risky situations and might be helpful for designing roadside advertisements regulations and risk prevention programs.  相似文献   
945.
The purpose of this pilot study was to determine whether perfluorooctanesulfonate (PFOS,C(8)F(17)SO(3)(-)) and perfluorooctanoate (PFOA,C(7)F(15)CO(2)(-)) concentrations in American Red Cross blood donors from Minneapolis-St. Paul, Minnesota have declined after the 2000-2002 phase-out of perfluorooctanesulfonyl-fluoride (POSF, C(8)F(17)SO(2)F)-based materials by the primary global manufacturer, 3M Company. Forty donor plasma samples, categorized by age and sex, were collected in 2005, and PFOS and PFOA concentrations were compared to 100 (non-paired) donor serum samples collected in 2000 from the same general population that were analyzed at the time using ion-pair extraction methods with tetrahydroperfluorooctanesulfonate as an internal standard. Eleven of the 100 samples originally collected were reanalyzed with present study methods that involved (13)C- labeled PFOA spiked into the donor samples, original samples, control human plasma, and the calibration curve prior to extraction, and was used as a surrogate to monitor extraction efficiency. Quantification was performed by high performance liquid chromatography tandem mass spectrometry methods. Among the 100 serum samples analyzed for PFOS, the geometric mean was 33.1 ng ml(-1) (95% CI 29.8-36.7) in 2000 compared to 15.1 ng ml(-1) (95% CI 13.3-17.1) in 2005 (p<0.0001) for the 40 donor plasma samples. The geometric mean concentration for PFOA was 4.5 ng ml(-1) (95% CI 4.1-5.0) in 2000 compared to 2.2 ng ml(-1) (95% CI 1.9-2.6) in 2005 (p<0.0001). The decrease was consistent across donors' age and sex. To confirm these preliminary findings, additional sub-sets of year 2000 samples will be analyzed, and a much larger biomonitoring study of other locations is planned.  相似文献   
946.
Atrazine sorption and fate in a Ultisol from humid tropical Brazil   总被引:1,自引:0,他引:1  
This study combined laboratory based microcosm systems as well as field experiments to evaluate the mobility of atrazine on a Ultisol under humid tropical conditions in Brazil. Results from sorption experiments fit to the Freundlich isotherm model [K(f) 0.99 mg kg(-1)/(mg l(-1))(1/n)], and indicate a low sorption capacity for atrazine in this soil and consequently large potential for movement by leaching and runoff. Microcosm systems using (14)C-atrazine to trace the fate of the applied herbicide, showed that 0.33% of the atrazine was volatilized, 0.25% mineralized and 6.89% was recorded in the leachate. After 60 d in the microcosms, 75% of the (14)C remained in the upper 5 cm soil layer indicating atrazine or its metabolites remained close to the soil surface. In field experiments, after 60 d, only 5% of the atrazine applied was recovered in the upper soil layers. In the field experiments atrazine was detected at a depth of 50 cm indicating leaching. Simulating tropical rain in field experiments resulted in 2.1% loss of atrazine in runoff of which 0.5% was adsorbed onto transported soil particles and 1.6% was in solution. Atrazine runoff was greatest two days after herbicide application and decreased 10 fold after 15 d. The use of atrazine on Ultisols, in the humid tropics, constitutes a threat to water quality, causing surface water and ground water pollution.  相似文献   
947.
The capacity to accumulate trace elements from the atmosphere of the lichens Hypogymnia physodes, Parmelia sulcata, Pseudevernia furfuracea and Usnea gr. hirta transplanted to an urban site of N Italy was compared. Twenty-nine elements (Al, As, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Fe, Hg, I, K, La, Mg, Mn, Ni, Pb, Rb, Sb, Sc, Se, Sm, Th, Ti, V, Zn) were analyzed by Instrumental Neutron Activation Analysis (INAA) and Electro-Thermal Atomic Absorption Spectroscopy (ET-AAS). The ratio between the concentrations of each element in exposed samples to that of control samples (exposed-to-control ratio and EC ratio) was used to investigate the accumulation rates of lichen thalli. The results showed that in general elements did not exhibit well defined trends, but rather showed fluctuations, and indicated that H. physodes, P. furfuracea and U. gr. hirta have a similar accumulation capacity, while that of P. sulcata is lower.  相似文献   
948.
Modeling in-situ uranium(VI) bioreduction by sulfate-reducing bacteria   总被引:1,自引:0,他引:1  
We present a travel-time based reactive transport model to simulate an in-situ bioremediation experiment for demonstrating enhanced bioreduction of uranium(VI). The model considers aquatic equilibrium chemistry of uranium and other groundwater constituents, uranium sorption and precipitation, and the microbial reduction of nitrate, sulfate and U(VI). Kinetic sorption/desorption of U(VI) is characterized by mass transfer between stagnant micro-pores and mobile flow zones. The model describes the succession of terminal electron accepting processes and the growth and decay of sulfate-reducing bacteria, concurrent with the enzymatic reduction of aqueous U(VI) species. The effective U(VI) reduction rate and sorption site distributions are determined by fitting the model simulation to an in-situ experiment at Oak Ridge, TN. Results show that (1) the presence of nitrate inhibits U(VI) reduction at the site; (2) the fitted effective rate of in-situ U(VI) reduction is much smaller than the values reported for laboratory experiments; (3) U(VI) sorption/desorption, which affects U(VI) bioavailability at the site, is strongly controlled by kinetics; (4) both pH and bicarbonate concentration significantly influence the sorption/desorption of U(VI), which therefore cannot be characterized by empirical isotherms; and (5) calcium-uranyl-carbonate complexes significantly influence the model performance of U(VI) reduction.  相似文献   
949.
The stabilization of hydrogen peroxide was investigated as a basis for enhancing its downgradient transport and contact with contaminants during catalyzed H(2)O(2) propagations (CHP) in situ chemical oxidation (ISCO). Stabilization of hydrogen peroxide was investigated in slurries containing four characterized subsurface solids using phytate, citrate, and malonate as stabilizing agents after screening ten potential stabilizers. The extent of hydrogen peroxide stabilization and the most effective stabilizer were solid-specific; however, phytate was usually the most effective stabilizer, increasing the hydrogen peroxide half-life to as much as 50 times. The degree of stabilization was nearly as effective at 10 mM concentrations as at 250 mM or 1 M concentrations. The effect of stabilization on relative rates of hydroxyl radical activity varied between the subsurface solids, but citrate and malonate generally had a greater positive effect than phytate. The effect of phytate, citrate, and malonate on the relative rates of superoxide generation was minimal to somewhat negative, depending on the solid. The results of this research demonstrate that the stabilizers phytate, citrate, and malonate can significantly increase the half-life of hydrogen peroxide in the presence of subsurface solids during CHP reactions while maintaining a significant portion of the reactive oxygen species activity. Use of these stabilizers in the field will likely improve the delivery of hydrogen peroxide and downgradient treatment during CHP ISCO.  相似文献   
950.
Reliable estimates of heavy-truck volumes in the United States are important in a number of transportation applications including pavement design and management, traffic safety, and traffic operations. Additionally, because heavy vehicles emit pollutants at much higher rates than passenger vehicles, reliable volume estimates are critical to computing accurate inventories of on-road emissions. Accurate baseline inventories are also necessary to forecast future scenarios. The research presented in this paper evaluated three different methods commonly used by transportation agencies to estimate annual average daily traffic (AADT), which is used to determine vehicle miles traveled (VMT). Traffic data from continuous count stations provided by the Iowa Department of Transportation were used to estimate AADT for single-unit and multiunit trucks for rural freeways and rural primary highways using the three methods. The first method developed general expansion factors, which apply to all vehicles. AADT, representing all vehicles, was estimated for short-term counts and was multiplied by statewide average truck volumes for the corresponding roadway type to obtain AADT for each truck category. The second method also developed general expansion factors and AADT estimates. Truck AADT for the second method was calculated by multiplying the general AADT by truck volumes from the short-term counts. The third method developed expansion factors specific to each truck group. AADT estimates for each truck group were estimated from short-term counts using corresponding expansion factors. Accuracy of the three methods was determined by comparing actual AADT from count station data to estimates from the three methods. Accuracy of the three methods was compared using n-fold cross-validation. Mean squared error of prediction was used to estimate the difference between estimated and actual AADT. Prediction error was lowest for the method that developed separate expansion factors for trucks. Implications for emissions estimation using the different methods are also discussed.  相似文献   
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