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1.
The frequency of some behaviour (such as self-centred gestures) increases during a task that leads to the occurrence of low-vigilance episodes. These gestures can be useful in stimulating oneself. A study carried out in 20 adults has enabled us to state that motor activity (recorded with an actimeter) increases with the duration of a monotonous driving task and sleep deprivation. The analysis of the scores recorded using the Karolinska Sleepiness Scale has shown that drivers can assess the deterioration of their state of vigilance according to the actual sleep preceding the driving test. Finally, the joint analysis of the subjective and objective data revealed a co-variation of these two types of indices. We discuss the stimulatory function of the motor activity in a task leading to the occurrence of low-vigilance episodes by investigating, among other things, the use, conscious or not, of this type of activity.  相似文献   

2.
In this study perceived mental stress during occupational work was compared to heart rate variability (HRV) using a traditional questionnaire and a novel wristop heart rate monitor with related software. The aim was to find HRV parameters useful for mental stress detection. We found the highest correlation between perceived mental stress with the differences between the values of triangular interpolation of rythm-to-rythm (RR) interval histogram (TINN) and the root mean square of differences of successive RR intervals (RMSSD) obtained in the morning and during the workday(r = -.73 andr = -.60, respectively). The analysis shows that as the RMSSD and TINN value differences increase from night to morning, the stress decreases.  相似文献   

3.
This study seeks to advance our understanding of the leadership consequences that may ensue when supervisors and their teams have similar versus differing orientations toward the past. Integrating a leader–team fit perspective with functional leadership theory, we cast incongruence between supervisor and team past temporal focus as a key antecedent of supervisors' active (i.e., task-oriented and relationship-oriented) and passive (i.e., laissez-faire) leadership behaviors toward the team. We tested our hypotheses in a team-level study that included a field sample of 84 supervisors and their teams using polynomial regression and response surface analyses. Results illustrated that supervisors demonstrated more task-oriented and relationship-oriented leadership when supervisors' and their team's past temporal focus were incongruent rather than aligned. Furthermore, in situations of supervisor–team congruence, supervisors engaged in less task-oriented and relationship-oriented leadership and more laissez-faire leadership with higher (rather than lower) levels of supervisor and team past temporal focus. In sum, these findings support a complex (mis)fit model such that supervisors' attention to the past may hinder their productive leadership behaviors in some team contexts but not in others. Hence, this research advances a novel, multiple-stakeholder perspective on the role of both supervisors' and their team's past temporal focus for important leadership behaviors.  相似文献   

4.
The arrangement of components plays a key role in the performance of complex Safety Instrumented Systems (SIS), in which a SIS logic solver is interlocked with other logic solvers, to share a final element, for instance. The position of the components and the way they are utilized affects the reliability characteristics, such as the Probability of Failure on Demand (PFD), Spurious Trip Rate (STR), architectural sensitivity and model uncertainty. This case study uses quantitative and qualitative approaches to elaborate on various aspects of component arrangement in complex SIS. Numerous simplified models are analyzed; new classification is introduced for SIS components based on their response to demand; a set of guidelines are developed for SIS architecture design, with a focus on component arrangement; and the use of these guidelines is demonstrated in a real-life example, where an existing turbine SIS is modified to incorporate a new over-speed protection system. The simplified models and the turbine upgrade project are also used to explain the issue of unknowns and uncertainties in reliability analysis and how these issues can be addressed in SIS architecture by optimizing component arrangement.  相似文献   

5.
IntroductionThis study sought to estimate the incidence, average cost, and total direct medical costs for fatal and non-fatal fall injuries in hospital, ED, and out-patient settings among U.S. adults aged 65 or older in 2012, by sex and age group and to report total direct medical costs for falls inflated to 2015 dollars.MethodIncidence data came from the 2012 National Vital Statistics System, 2012 Healthcare Cost and Utilization Project-Nationwide Inpatient Sample, 2012 Health Care Utilization Program National Emergency Department Sample, and 2007 Medical Expenditure Panel Survey. Costs for fatal falls were derived from the Centers for Disease Control and Prevention's Web-based Injury Statistics Query and Reporting System; costs for non-fatal falls were based on claims from the 1998/1999 Medicare fee-for-service 5% Standard Analytical Files. Costs were inflated to 2015 estimates using the health care component of the Personal Consumption Expenditure index.ResultsIn 2012, there were 24,190 fatal and 3.2 million medically treated non-fatal fall related injuries. Direct medical costs totaled $616.5 million for fatal and $30.3 billion for non-fatal injuries in 2012 and rose to $637.5 million and $31.3 billion, respectively, in 2015. Fall incidence as well as total cost increased with age and were higher among women.ConclusionMedically treated falls among older adults, especially among older women, are associated with substantial economic costs.Practical applicationWidely implementing evidence-based interventions for fall prevention is essential to decrease the incidence and healthcare costs associated with these injuries.  相似文献   

6.
The process industry has made major advancements and is a leader in near-miss safety management, with several validated models and databases to track close call reports. However, organizational efforts to develop safe work procedures and rules do not guarantee that employees will behaviorally comply with them. Assuming that at some point, every safety management system will need to be examined and realigned to help prevent incidents on the job, it is important to understand how personality traits can impact workers' risk-based decisions. Such work has been done in the mining industry due to its characteristically high risks and the results can be gleaned to help the process industry realign goals and values with their workforce. In the current study, researchers cross-sectionally surveyed 1,334 miners from 20 mine sites across the United States, varying in size and commodity. The survey sought to understand how mineworkers' risk avoidance could impact their near miss incidents on the job – a common precursor to lost-time incidents. Multiple regressions showed that as a miner's level of risk avoidance increased by 1 unit in the 6-point response scale, the probability of experiencing a near miss significantly decreased by 30% when adjusting for relevant control variables. Additionally, a significant interaction between risk avoidance and locus of control suggested that the effect of risk avoidance on near misses is enhanced as a miner's locus of control increases. A one-unit increase in locus of control appends the base effect of risk avoidance on near misses with an additional 8% decrease in the probability. Findings are discussed from a near-miss safety management system perspective in terms of methods to foster both risk avoidance and locus of control in an effort to reduce the probability of near misses and lost time at the organizational level within the process industry and other high-hazard industries.  相似文献   

7.
The primary purpose of this paper is to provide a human factors engineering (HFE) checklist for human–system interfaces (HSIs) upgrades in nuclear power plants (NPPs). The HFE checklist is used to review the HSIs design submittals prepared by licensees or applicants for a license or design certification of a HSI upgrade. NUREG-series regulation documents are used to develop the main frame of the initial HFE checklist. The contents of the HFE checklist are constructed by the theories and principles governing human factors. Then, verification and validation (V&V) of the HFE checklist is accomplished by validity and reliability evaluation. The results show that the HFE checklist has sufficient validity and reliability for the review of HSI upgrades in NPPs.  相似文献   

8.
At Seveso plants, duty holders must have a complex system for assessing and managing risks. The pillars of this system are the safety report and the safety management system, with a number of underlying documents. The strength of the system is the high standardization of these documents. Regulations, standard codes and guidelines define content, structure and formats. The weakness is the high complexity. Managers and workers perceive documents as difficult to understand and far from actual operations. Major threats for the credibility of documents (and therefore for the safety systems) come from the continuous organizational and technical changes, which in a short time can make most documents obsolete; as well as by near misses, which continuously show the holes in safety systems. A big effort is required to follow up the plant changes and the near misses. In order to help safety managers, a new software has been developed. At Seveso plants, it has been possible build an integrated digital representation, because all documents are perfectly structured. This representation may be used both for updating the relevant documents after a change and to improve documents after a near miss or an accident. In this way, safety documents are always up to date and trustworthy and the huge knowledge, which is usually hidden inside safety documents, is clearly revealed and revived. The approach is basically “knowledge based” and the intention is to provide safety managers with an easy and simple tool. IRISonLine is a software that has been developed by ISPESL to provide safety managers of “Seveso” establishments with a tool for improving the management of change and of near misses.  相似文献   

9.
Objective: The objective of this study was to estimate the safety benefits of in vehicle lane departure warning (LDW) and lane keeping aid (LKA) systems in reducing relevant real-world passenger car injury crashes.

Methods: The study used an induced exposure method, where LDW/LKA-sensitive and nonsensitive crashes were compared for Volvo passenger cars equipped with and without LDW/LKA systems. These crashes were matched by car make, model, model year, and technical equipment; that is, low-speed autonomous emergency braking (AEB) called City Safety (CS). The data were extracted from the Swedish Traffic Accident Data Acquisition database (STRADA) and consisted of 1,853 driver injury crashes that involved 146 LDW-equipped cars, 11 LKA-equipped cars, and 1,696 cars without LDW/LKA systems.

Results: The analysis showed a positive effect of the LDW/LKA systems in reducing lane departure crashes. The LDW/LKA systems were estimated to reduce head-on and single-vehicle injury crashes on Swedish roads with speed limits between 70 and 120 km/h and with dry or wet road surfaces (i.e., not covered by ice or snow) by 53% with a lower limit of 11% (95% confidence interval [CI]). This reduction corresponded to a reduction of 30% with a lower limit of 6% (95% CI) for all head-on and single-vehicle driver injury crashes (including all speed limits and all road surface conditions).

Conclusions: LDW/LKA systems were estimated to lower the driver injury risk in crash types that the systems are designed to prevent; that is, head-on and single-vehicle crashes. Though these are important findings, they were based on a small data set. Therefore, further research is desirable to evaluate the effectiveness of LDW/LKA systems under real-world conditions and to differentiate the effectiveness between technical solutions (i.e., LDW and LKA) proposed by different manufacturers.  相似文献   


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Objective: In Sweden, a joint action method called SMADIT is in use, where the police quickly offer help from the social services or the dependency care and treatment service to suspected drink drivers. The objective of this article is to analyze the experiences of suspected drink drivers who accepted the offer of help and what it meant for them. The knowledge can be used to improve procedures and consultations. Furthermore, it can allow the basic premises of the method to be examined; for example, the importance of offering help quickly.

Methods: To enable comparisons over time, in-depth interviews were conducted with 12 suspected drink drivers on 2 occasions with 1 year between.

Results: To varying degrees the informants knew about their alcohol problems but were unsure whether they would have sought help by themselves. Therefore, the original ideas of the method with an initial contact with the social services or the dependency care and treatment service within 24 h was found to be important. However, the results also showed that some of the informants needed some time before the first meeting because they were in shock from the drink driving incident or in need of sleep. Therefore, the drink driver's situation and individual wishes always have to be considered. The article also shows that an encouraging attitude among the police, the social services, and the dependency care and treatment service is important for the success of the SMADIT method.

The informants are satisfied with the method and in retrospect the incident and the SMADIT offer of help are described as a turning point in their lives. One year after being offered help the informants were no longer focused solely on the personal consequences of drink driving, as they were shortly after the incident. Instead, they had gained insights into the harm they could have done to other road users when they drove while drunk.

Conclusions: One conclusion from this article is that SMADIT, as an innovative method that can be deployed more rapidly than other alcohol-impaired driving countermeasures, should be considered as a good complement to conventional methods to deal with drink driving. Based on the results, we recommend a trial of the joint action method against drink driving in other jurisdictions.  相似文献   


12.
Rune Elvik 《Safety Science》2010,48(9):1189-1196
This paper discusses how incentives for setting efficient priorities in road safety policy can be strengthened. Efficient priorities are characterised by the use of cost-effective road safety measures. Cost-effective road safety measures can be identified by means of cost-benefit analyses. Studies of the actual priorities in road safety policy, in particular in the Scandinavian countries, suggest that these priorities are inefficient, i.e. characterised by the non-use or sub-optimal use of cost-effective road safety measures as well as an extensive use of ineffective road safety measures. This occurs despite the fact that road safety policy analyses have included extensive cost-benefit analyses of road safety measures. It would thus appear that cost-benefit analyses do not necessarily generate a sufficient incentive to implement cost-effective road safety measures. Possible reasons for this are discussed in the paper. It is argued that a large part of the monetary benefits of road safety measures, as estimated in cost-benefit analyses, are not subject to market transactions, and do therefore not manifest themselves in the form of increased income or higher profits. While cost-benefit analyses are indispensable as a means of identifying cost-effective road safety measures, their influence on actual road safety policy needs to be strengthened by providing additional incentives for the use of cost-effective road safety measures. It is suggested that a system of road pricing could generate such incentives. A brief sketch of a hypothetical system of road pricing is given and some problems associated with the implementation of this system are discussed.  相似文献   

13.
Assessment of the risk of exposure to a “dangerous dose” (DD) is the basis of the UK Health and Safety Executive's HSE's current risk assessments for land-use planning (LUP). Some years ago, a hybrid approach using both DD and “significant likelihood of death” (SLOD) was proposed as an improvement, but was not adopted.Here, an alternative, weighted multiple threshold approach, provisionally titled “total risk of death” (TROD), is described. TROD improves the comparability of assessed risks from diverse hazards. This is achieved by first performing assessments for more than one threshold of consequence (such as DD assessment and SLOD assessment). The predicted risk for each threshold is then combined into a single risk value (at a specified location) by weighting the contributions to risk according to the predicted consequences for each threshold.This paper makes the case, in principle, for using TROD and illustrates how TROD values are constructed.TROD overcomes some of the objections that have barred progress to more widespread use of risk assessment, it is more comparable between different installations and hazards than DD, it is more sensitive than SLOD and more adaptable than probits (which can introduce a false sense of precision). It could support more direct comparison with other risks (e.g. everyday risks and transport risks) in the future.The appropriate “weightings” for addition of risks predicted for different consequence thresholds (contributing to TROD) are discussed here. A three-threshold scheme for evaluation of TROD is described. The thresholds are DD (assumed to approximate to a dose leading to ~1% fatal consequences or LD1), LD10, and SLOD (~LD50).TROD has been used in HSE sponsored research and in HSE's exploration of societal risks.  相似文献   

14.
Guards on machine tools are meant to protect operators from injuries caused by tools, workpieces, and fragments hurled out of the machine’s working zone. This article presents the impact resistance requirements, which guards according to European safety standards for machine tools must satisfy. Based upon these standards the impact resistance of different guard materials was determined using cylindrical steel projectiles. Polycarbonate proves to be a suitable material for vision panels because of its high energy absorption capacity. The impact resistance of 8-mm thick polycarbonate is roughly equal to that of a 3-mm thick steel sheet Fe P01. The limited ageing stability, however, makes it necessary to protect poycarbonate against cooling lubricants by means of additional panes on both sides.  相似文献   

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17.
The starting point for this article is the need to develop empirical insights about contemporary societal risk and safety management practice and executive structures. In order to facilitate insights about societal risk and safety management in a Scandinavian welfare context we use Sweden and its local governmental level (municipal) as an empirical frame in this paper. The aim for this article is to analyse how a variety of risk and safety management tasks are divided within the Swedish municipalities. The objectives are to frame the current directions for internal allocations of risk and safety issues by providing an empirically based executive typology and to contemplate the implications and future research needs that arise from that management pattern.The analysis is based on statistical analysis of information from a web-survey with chief officials (n = 1283) with responsibilities for different municipal functions and sectors. In this study the responses to one of the survey questions are used for statistical analysis. The analyzed question focused on the degree that the respondents estimated that their administrative sector or function handled a selection of risk and safety management assignments (n = 45). A factor analysis was applied to identify patterns in the dataset. The analysis resulted in an eight factor solution with a high degree of explained variance (74.3%). The results provide an elementary contribution to the understanding of the current societal risks and safety management directions.  相似文献   

18.
Attention has been focused on the treatment of lignite-fired flue gas in order to use lignite in an environmentally friendly way – (i) low-CO2 emission, (ii) production of a valuable by-product, (iii) no discharge of wastewater, (iv) direct removal of SO3 (strong toxicity), and (v) treatment of high SO2 concentration. Based on these criteria, electron beam irradiation with ammonia injection was tested on a semi-pilot scale: 800 Nm3 h?1 flow rate, 5500 ppm SO2, 70 ppm NOx, 22% flue gas moisture, and 75–80 °C at the reactor outlet.As an energy-saving measure, a low dose (5 kGy) of irradiation was applied: the problem lay in the by-product quality. It is considered that (NH4)2SO3 and NH4HSO3 produced by thermal reactions are oxidized to form (NH4)2SO4 (fertilizer) by an electron beam. However, not all reactions were complete because the by-product contained small amounts of H2SO4 and NH2SO3NH4 (herbicide), so a vegetable pot test was performed to study the by-product quality: no adverse effect was observed. It is inferred from the pot test that slightly acidic soil may protect vegetables from disease and a small amount of NH2SO3NH4 probably affects woody species and not herbaceous species.It is concluded that the electron beam system is noted as a multi-component pollution control process (removal of NOx, SO3, SO2 and dioxins) and this system will contribute to environmentally friendly use of lignite as well as agricultural productivity via fertilizer supply.  相似文献   

19.
Social ties with high-status others can be a potent signal of an individual's underlying quality and future promise. Individuals in competitive markets, therefore, have an incentive to publicly claim connections to high-status others. However, cognitive limitations and biases can make social network connections difficult for observers to reliably discern, and claims to high-status ties can go unrecognized by the audience. Our core contention is that claims to high-status affiliation are advantageous only when the audience recognizes the claim—unrecognized claims, like unreliable signals, do not deliver advantage and can backfire. Further, we draw on the literature on imprinting and develop arguments for why some people are more likely to make claims to high-status ties and why some claims to high-status ties are more likely than others to be recognized by the audience. We test our arguments with data from the market for head coaching jobs in NCAA basketball (2000–2011). Our study contributes to the sparse literature on how social network ties that exist in the minds of third-party observers influence individual attainment in market settings; and it offers new insights into how imprinting processes shape the perception and use of high-status network ties.  相似文献   

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