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161.
An assignment to carry out a hazard study and risk analysis of a gas processing complex has been described briefly, wherein well known procedures have been used to identify and investigate potential hazards. A method of avoiding unintentional overfilling of LPG storage tanks has been recommended, which utilizes the existing level control instruments.  相似文献   
162.

Introduction

The purpose of this study was to analyze linked crash and hospital data to determine the effect that enactment of a standard enforcement safety belt law in Ohio would have on hospital charges and direct medical costs due to motor-vehicle crashes, focusing on the impact to the state's Medicaid system.

Method

The linkage and analysis was conducted as part of the Ohio Crash Outcome Data Evaluation System (CODES) program. Current safety belt usage in Ohio stands at 82% with its secondary enforcement safety belt law.

Results

Assuming an increase in usage to 92% through standard enforcement, over $15.3 million in medical costs to Medicaid for injuries that occur in a single year could be prevented over a 10-year period. Cumulative savings could reach more than $91.2 million during the 10-year period. In addition, 161 fatalities could have been prevented in one year had all unbelted occupants who sustained a fatal injury instead chosen to wear their safety belt.

Summary and Impact on Industry

Clearly, substantial progress can be made in reducing the number of deaths and injuries, as well as medical costs associated with motor-vehicle crashes, by strengthening safety belt laws and increasing safety belt usage in Ohio.  相似文献   
163.
Subjective or perceived control over job-related activities or events is a frequently measured construct in organizational stress research. Karasek (1985) assessed perceived control as both decision authority and skill discretion at work (job decision latitude). Ganster (1989b; Dwyer and Ganster, 1991) developed a multidimensional or general measure of worker control, as well as a specific measure of work predictability. Because little published psychometric data exist for these scales, we investigated the item-level measurement properties of Karasek's and Ganster's measures. We hypothesized two separate, two-factor solutions, decision authority and skill discretion, for the job decision latitude scale, and general control and predictability, for the work control scale. The dimensionality of both measures was assessed in multiple, independent samples using confirmatory factor analyses (LISREL) with maximum likelihood estimation. Simultaneous solutions across samples were used to determine the fit of the factor models to the data. The hypothesized two-factor solutions were confirmed for both Karasek's and Ganster's scales, although item refinement is indicated. We also investigated the relative independence between Karasek's and Ganster's scales and found a lack of independence between the general control and decision authority items in one sample. © 1997 John Wiley & Sons, Ltd.  相似文献   
164.
165.
Intelligent Vehicle-Highway Systems (IVHS) have been proposed in the wake of rapid worldwide growth in traffic volume and density. These systems involve the application of advanced sensor, communications, computational, and control technologies to the design of highways and vehicles to improve traffic flow and safety. Similar technologies have been applied in other transportation systems such as aviation and air-traffic control, and it is suggested that the human factors insights derived from these systems can be usefully applied, proactively rather than retroactively, in IVHS design. Several safety and human factors issues relevant to the design of IVHS technologies, both near-term and long-term, are discussed, including: (a) the optimization of driver mental workload in highly-automated “hybrid” systems; (b) the design of in-vehicle navigation aids and the resolution of display conflicts; (c) individual and group differences in driver behavior and their implications for training and licensure; (d) the evolution and integration of IVHS technologies; and (e) traffic management and the regulation of driver trust in IVHS. Successful resolution of these issues and their incorporation in IVHS design will provide for fully functional systems that will serve the twin needs of reducing traffic congestion and improving highway safety.  相似文献   
166.
To provide evidence of the relationship between expectations for the values that should be exhibited for effective performance by female and male managers and their actual values, data were used that had been collected as part of a leadership program conducted for managers of business organizations in the United States. From a pool of approximately 700 managers, samples were drawn of 130 male and 130 female managers. As part of leadership program, the managers had completed 26-item SYMLOG value questionnaires, rating themselves and the values they judged to be effective for a manager. Prior to their participation in the program, sets of ratings were made by the coworkers of each manager, rating the actual values of the manager and the coworkers' ideal profile for the manager. The questionnaire covers three dimensions of values: dominant versus submissive, friendly versus unfriendly, and accepting the task-orientation of established authority versus opposing it. Comparisons were made of self and coworkers' ratings on the observed (self/actual) and model (effective/ideal) values of female and male managers with ‘matched’ samples that include only female and male managers with similar ratings of actual values, as judged by their coworkers, by removing the ratings of ‘outliers’. The only significant difference in gender ratings that remains is that female managers rate themselves as more positive. There are more differences between observed and model ratings. Managers and their coworkers believe that model managers should be more dominant and friendly than they are rated to be. However the managers also believe that they should be more task-oriented while their coworkers believe that they should be less task-oriented. The majority of the female managers dropped from the matched sample because no matching male could be found were more dominant and positive and less task-oriented, thus closer to the stereotype role for females. © 1997 John Wiley & Sons, Ltd.  相似文献   
167.
OBJECTIVE: The primary objective of the study was to determine if drinking patterns on the days immediately prior to an alcohol-related motor vehicle crash (ARMVC) were significantly different than drinking patterns in the weeks prior to the crash. METHODS: Following ARMVC, 187 hospitalized non-alcohol dependent young-adults (43 females, 144 males) were enrolled. Mean age was 29.03 years, mean blood alcohol level was 165.18 mg/dL, and mean injury severity score was 10.50. When alcohol-free, subjects were interviewed by nurse clinicians to determine the quantity/frequency of alcohol consumption during the 28 days prior to the crash. Subjects reported the number of standard drinks using the Timeline Followback procedure. Total drinks/day were determined, with day 1 considered 4 weeks prior to the crash and day 28 the day of the crash. A random-intercepts general linear mixed model (GLMM) was used to test the effect of several covariates (segment 1 [days 1-26], segment 2 [days 27-28], age, sex, race, holiday/non-holiday period, driver/passenger status, and weekend/weekday crash) on the amount of standard drinks/day. RESULTS: There was no significant interaction among the covariates. The only significant predictors of drinks/day were segment 2 (b = .322, p < .0001) and gender (b = -.221, p = .016). The positive, statistically significant slope for segment 2 indicated an increase in consumption of drinks/day in the two-day period prior to the ARMVC and the negative slope for gender indicated greater consumption of drinks/day for men than women. CONCLUSION: Persons injured in an ARMVC had a significant increase in alcohol consumption on the day before and the day of vehicular crashes (days 27 and 28) as compared to the first 26 days in the 28-day period preceding the crash. When non-alcohol-dependent subjects are counseled to reduce their risk of traffic crashes, they should be alerted that when their patterns of drinking change, they are at higher risk than usual for a crash.  相似文献   
168.
This paper deals with a sensitivity analysis of main parameters affecting the measurement of the gas flowrate emitted during testing substances for their potential to emit flammables gases in dangerous quantities where in contact with water, according to the UN N.5 test procedure. UN N.5 is described in the Manual of Tests and Criteria of United Nations (part of the Orange Book) (ONU Manual of Test and Criteria, 2008), serving both applications of international transport regulations as well as classifications of dangerous substances according to Globally the Harmonized System (GHS) and the derived regulation applying in the EU known as “CLP” Regulation (Regulation (EC) No 1271/2008). The main reason that justifies the present research is that the measurement of emitted gases is highly critical in the final classification resulting from the interpretation of the test results. Moreover, that idea has been raised to adapt the UN N.5 test protocol for classifying, in the future, substances that by contact with water would emit dangerous quantities of toxic gases.Experiments have been carried out to cover the analysis of the influence of ambient temperature, overall volume of glassware, nature of aqueous media, mass sample and sample-to-liquid mass ratio, since such parameters are not fixed within any defined range in the UN N.5 test procedure. The influence of the flow rate measuring device was also considered. Results confirm that the above mentioned parameters may play a significant role to such an extent as to finally alter the final classification resulting from the testing. Guiding principles have also been derived from our measurements and observations towards an improved and more robust UN test protocol in the future.  相似文献   
169.
This is the third update of research on graduated driver licensing (GDL) and related teenage driver issues. It briefly summarizes research published since or not included in the 2005 update (Hedlund, J., & Compton, R. (2005). Graduated driver licensing research in 2004 and 2005. Journal of Safety Research, 36(2), 109-119.), describes research in progress of which the authors are aware, and announces plans for a symposium on teenage driving and GDL to be held in February 2007.  相似文献   
170.
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