A tool (called CESMA) was developed to carry out cost–benefit analyses and cost-effectiveness analyses of prevention investments for avoiding major accidents. A wide variety of parameters necessary to calculate both the costs of the considered preventive measures and the benefits related with the avoidance of accidents were identified in the research. The benefits are determined by estimating the difference in (hypothetical) major accident costs without and with the implementation of a preventive measure. As many relevant costs and benefits as possible were included into the tool, based on literature and expert opinion, in order to be able to deliver an all-embracing cost–benefit analysis and cost-effectiveness analysis to assist in the investment decision process. Because major accidents are related to extremely low frequencies, the tool takes the uncertainty of the unwanted occurrence of a major accident into account through the usage of a so-called ‘disproportion factor’. Compared with existing software, the CESMA tool is innovative by striving for an as-accurate-as-possible picture of costs and benefits of major accident prevention, and taking the uncertainties accompanying disastrous events into consideration. Furthermore, an illustrative example of CESMA is presented in the paper. 相似文献
Flocculation is an essential phenomenon in industrial wastewater treatment. Inorganic coagulants (salts of multivalent metals) are being commonly used due to its low cost and ease of use. However, their application is constrained with low flocculating efficiency and the presence of residue metal concentration in the treated water. Organic polymeric flocculants are widely used nowadays due to its remarkable ability to flocculate efficiently with low dosage. However, its application is associated with lack of biodegradability and dispersion of monomers residue in water that may represent a health hazard. Therefore, biopolymers based flocculants have been attracting wide interest of researchers because they have the advantages of biodegradability and environmental friendly. But, natural flocculants are needed in large dosage due to its moderate flocculating efficiency and shorter shelf life. Thus, in order to combine the best properties of both, synthetic polymers are grafted onto the backbone of natural polymers to obtain tailor-made grafted flocculants. This paper gives an overview of the development of different types of flocculants that were being investigated for treatment of industrial wastewater. Furthermore, their flocculation performance will be reviewed and the flocculation mechanism will be discussed. 相似文献
This paper presents data on the limiting (minimum) concentrations of hydrogen in oxygen, in the presence of added helium, at elevated temperature and pressure related to the practical operational case. A 5 L explosion vessel, an ignition sub-system and a transient pressure measurement sub-system were used. Through a series of experiments carried out using this system, the limiting concentrations of hydrogen in oxygen and helium at different initial pressures and temperatures for the practical operational case were studied, and the influence of ignition energy and initial temperature on the limiting concentration of hydrogen in oxygen and helium was analyzed and discussed. The variation of ignition energy within the studied range is found to have a significant effect on the limiting concentration of hydrogen in oxygen and helium at lower initial temperature. However, when the ignition energy is higher than 32 mJ, the limiting hydrogen concentration remains almost changeless as the initial temperature increases from 21 °C to 90 °C. The limiting explosible concentration of hydrogen–oxygen–helium mixture decreases as the ignition energy increases when the initial temperature is lower. When the initial temperature is higher, the ignition energy has little effect on the limiting hydrogen concentration of hydrogen–oxygen–helium mixtures. When the initial temperature reaches 90 °C, the limiting hydrogen concentration remains almost changeless with an increase in ignition energy. The limiting explosible concentration of hydrogen in the mixtures, at the initial temperature of 21 °C and the ignition energy of 0.5 mJ, is 8.5% and that of oxygen is 11.25%. 相似文献
AbstractObjectives: What are we teaching drivers about safely interacting with cyclists? This is the main objective of the Cycle Aware project. As part of the study, a teaching and learning package is being developed to fill this gap in Australia.Methods: Cycle Aware is a major national project that takes a mixed methods approach to investigate how cyclists are taught to share the road with cyclists when learning to drive. The project has five stages: (1) a national review of the driver licensing documentation; (2) interviews with key stakeholders (n?=?35) involved with novice driver education; (3) analysis of cyclist-novice driver crash data to identify the most frequent crash types; (4) develop a teaching and learning package (Cycle Aware Package), and; trial and evaluate Cycle Aware Package.Results: Overall, drivers are taught little about sharing the road with cyclists. Representation of cyclists in government documentation is mixed and mostly negative and interviews identified driver-cyclist tensions related to attitudes and awareness of sharing the road. Crash types were similar among novice and experienced drivers. The Cycle Aware Package is being finalised and will be trialled in South Australia and Northern Territory in early 2019.Conclusions: Cycle Aware will provide new insights into the way drivers are taught to share the road with cyclists. The Cycle Aware Package with interactive online content and driver competencies will facilitate a new approach to addressing this gap among Australia drivers. 相似文献
In order to enhance Chinese workers’ occupational safety awareness, it is essential to learn from developed countries’ experiences. This article investigates thoroughly occupational safety and health (OSH) in China and the UK; moreover, the article performs a comparison of Chinese and British OSH training-related laws, regulations and education system. The following conclusions are drawn: China’s work safety continues to improve, but there is still a large gap compared with the UK. In China a relatively complete vocational education and training (VET) system has been established. However, there exist some defects in OSH. In the UK, the employer will not only pay attention to employees’ physiological health, but also to their mental health. The UK’s VET is characterized by classification and grading management, which helps integrate OSH into the whole education system. China can learn from the UK in the development of policies, VET and OSH training. 相似文献
Objective: The purpose of this study was to identify and better understand the features of fatal injuries in cyclists aged 75 years and over involved in collisions with either hood- or van-type vehicles.
Methods: This study investigated the fatal injuries of cyclists aged 75 years old and over by analyzing accident data. We focused on the body regions to which the fatal injury occurred using vehicle–bicycle accident data from the Institute for Traffic Accident Research and Data Analysis (ITARDA) in Japan. Using data from 2009 to 2013, we examined the frequency of fatally injured body region by gender, age, and actual vehicle travel speed. We investigated any significant differences in distributions of fatal injuries by body region for cyclists aged 75 years and over using chi-square tests to compare with cyclists in other age groups. We also investigated the cause of fatal head injuries, such as impact with a road surface or vehicle.
Results: The results indicated that head injuries were the most common cause of fatalities among the study group. At low vehicle travel speeds for both hood- and van-type vehicles, fatalities were most likely to be the result of head impacts against the road surface.
The percentage of fatalities following hip injuries was significantly higher for cyclists aged 75 years and over than for those aged 65–74 or 13–59 in impacts with hood-type vehicles. It was also higher for women than men in the over-75 age group in impacts with these vehicles.
Conclusions: For cyclists aged 75 years and over, wearing a helmet may be helpful to prevent head injuries in vehicle-to-cyclist accidents. It may also be helpful to introduce some safety measures to prevent hip injuries, given the higher level of fatalities following hip injury among all cyclists aged 75 and over, particularly women. 相似文献