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591.
N. Hamidi  M. Meftahi 《Safety Science》2012,50(5):1180-1189
Nowadays, with implementation of management systems and environment management and due to the influence of safety and health issues on working processes, organizations have also sought to acquire health and safety management systems. This study which aims to examine the influence of integrated management system on safety and productivity indices has retrospective experimental nature. It was conducted in Cement Factories in which three systems are used: quality, environment and safety systems. The collected data were: accident reports and the investigation of events in 6 years during 2005-2010 (3 years before and 3 years after the implementation of the system). The safety indices that used in this study are: IFR, ISR, FSI, and Safe T. Score. Then, the data analyzed with the T-test, mean and standard deviation. The results showed a significant difference between various safety indices before and after the implementation. The examination of production indices such as increasing rate of productivity and production indicates the influence of these systems on production and productivity indices. The results have showed that the safety system existence cannot ensure productivity increase. Indices definition can be helpful for the safety system effectiveness and system continual improvement. It is important to say that there might be various indices definition in different industries.  相似文献   
592.
The present paper shows a numerical investigation of dust lifting behind a moving pressure wave. The dispersion of combustible dust has previously been discovered to be a precursor to a potential dust explosion. Consequently, a growing interest on the subject has been observed in recent years. Numerous studies have been performed on dust lifting, however, very few investigations have focused on dust layers with high volume fractions. Therefore, the aim of this investigation was to provide additional data. The simulations were carried out in a three-dimensional duct with a dust layer dispersed along the lower wall. The Eulerian–Eulerian approach was selected as the modelling technique. At first, four simulations varying the initial pressure and volume fraction of the dust were performed. The former parameter was varied between 4 and 8 bar, while the latter varied between 0.4 and 0.6. The combination of high initial pressure and high volume fraction resulted in the greatest dispersion of dust. Subsequently, two different drag force models were compared: the Schiller–Naumann, and the Gidaspow. It was discovered through this research that the choice of model caused significantly different results. The former model was found to underestimate the drag in the diluted parts of the layer. Consequently, this led to a distinctly lower lifting of the dust than in the latter model. Finally, a validation of a particle–particle interaction model was performed. It was observed that in the case where the model was disabled, an unrealistically high maximum volume fraction of the dust layer occurred. Nevertheless, the model did not seem to improve the dispersion results, which indicates that the dust lifting in this research was solely due to fluid–particle interactions.  相似文献   
593.
国际河流管理合作模式的分类及演进规律探讨   总被引:2,自引:1,他引:1  
论文对国际河流管理合作模式的概念、分类及演进规律进行了探讨。在从合作主体、目标、途径、制度等方面对合作模式进行单维度分类的基础上,借鉴霍尔三维结构图系统分析方法,构建了合作模式三维度分类模型,较全面、准确地概括了当前国际河流管理合作实践的模式类型。最后,综合世界各种典型国际河流管理合作模式的形成和发展过程,从模式要素的发展演变及模式演进的动力机制两个方面入手,详细阐述了国际河流管理合作模式的演进规律。  相似文献   
594.
Summary

The Ecological Footprint (EF) is a method for estimating the biologically productive area necessary to support current consumption patterns, given prevailing technical and economic processes. By comparing human impact with the planet's limited bioproductive area. this method tests a basic ecological condition for sustainability. The ecological footprint has gained popularity for its pedagogical strength as it expresses the results of its analysis in spatial units that can easily be communicated. Many EF estimates have been performed on a global, national and sulrnationallevel. In this paper. we review the method and critically assess it from a sustainability perspective based on first order principles. We examine: ? Which aspects of sustainability are already covered by existing EF assessments;

? Which further aspects ofsustainability could be made accountable through the EF (such as areas needed to assimilate waste streams that are not yet accounted for in present assessments); and

? Those aspects ofsustainability that cannot be accountable through the EF. Thereby needing complimentary auditing tools.

Since the EF is a measure of renewable biocapacity, we argue that some dimensions of ecological sustainability should not be included in the EF. These include human activities that should be phased out to obtain sustainability, such as emissions of persistent compounds foreign to nature and qualitative aspects that represent secondary uses of ecological areas and do not, therefore, occupy a clearly identifiable additional ecological space. We also conclude that the EF is useful for documenting the overall human use or abuse of the potentially renewable functions and services of nature. Particularly, by aggregating in a consistentway a varity of human impacts, it can effectively identify the scale of the human economy by companson with the size of the biosphere.  相似文献   
595.
596.
Through high pressure oedometer-undrained triaxial tests and dynamic triaxial tests, researches were conducted on the static and dynamic strength characteristics of the tailings silty sand of No. 4 tailings reservoir in De-xing copper mine. The Mohr-stress circles of the tailings silty sand under all the testing confining pressure show that the single line failure envelope cannot represent the strength characteristics absolutely, the double line failure envelope can express the strength properties when confining pressures are less than 1400 kPa, and the parabolic failure envelope can reflect the strength characteristics well under all the testing confining pressures. The grading curve of the tailings silty sand indicates that the grain composition is relatively homogeneous. Thus, the tailings silty sand is susceptible to liquefy under the dynamic loading. Dynamic triaxial tests of the tailings silty sand show that the tailings silty sand in deep areas has more liquefaction resistance strengths than in shallow. The possible explanation is that the structure of the deep tailings silty sand is more stable than the shallow one. The tests also reveal that the liquefaction resistance increases with the dry density when it is in the range of 1.51-1.61. The results can be used to guide the construction and ensure the safety of No. 4 tailings dam or other high tailings dams.  相似文献   
597.
The purpose of this paper is to discuss the service attributes of ports for ship navigation safety. Based on the relevant literature and the features of ship navigation in ports, the service attributes of ports for ship navigation were first investigated. A fuzzy AHP model was then used to identify those attributes from shipmasters’ perspectives. Finally, a Dissatisfaction Attitude (DA) index was used to determine the attributes’ priorities, by which the port authorities may make policies for improving ship navigation safety. As an empirical study, the shipmasters berthing their ships in Kaohsiung Port were surveyed to validate the model. The result constructs 19 port service attributes (SAs) for ship navigation safety, in which, the shipmasters place more emphasis on the SAs of operators’ professional literacy, including the marine pilot’s professional and English communication abilities, the VTC (Vessel Traffic Center) regulator’s professional and English communication abilities, and the tugboat driver’s skills. While, for Kaohsiung Port, currently, the traffic control of fairway is the most important aspect to be improved. The theoretical and managerial implications of the findings for port authorities in improving ship navigation safety are discussed.  相似文献   
598.
To evaluate the effect of the long-term operation of a salt cavern in a given construction on rock deformation and its stability, tri-axial creep tests to the glauberite, anhydrite, and argillaceous rock salt are conducted, from which the creep curves as well as exponential functions of strain rate during the steady creep stage and creep constitutive equations of different rock salt in the experimental process derived are obtained. The study results show that: (i) Under the same deviatoric stress, the strain rate of argillaceous rock salt is lower than the glauberite and anhydrite, and the difference becomes larger with the increase of the deviatoric stress; (ii) The creep constitutive equations of different kinds of rock salt are in good agreement with the Burgers model, besides which the respective characteristics of these two creep models are compared. The change of creep parameters also illustrates the discrepancy of rock salt. The researching results can provide some references for long-term stability analysis of gas storage in salt caverns.  相似文献   
599.

Aims

A sociological and anthropological view of culture was used to investigate how work culture, independent of “safety culture”, may affect safety in the workplace. We explored how work cultures of nurses and physical/occupational therapists (PT/OTs) in two acute care hospitals are related to the adoption of patient lifting devices.

Methods

Focus groups were conducted between 2006 and 2009, seven with nurse staff (n = 39) and two with PT/OT staff (n = 17), to explore issues concerning a Minimal Manual Lift Environment policy, initiated in 2004, and subsequent use of patient lift equipment. Audio recordings of the sessions were transcribed; text data were analyzed using N6-QSR. Cultural facilitators and barriers to the adoption of patient lift equipment were examined.

Results

Data revealed cultural similarities and differences between these healthcare professions. Both displayed a “patient first” approach to care-giving which may promote lift device use for patients’ benefits, not necessarily for staff safety. Also, the implied purpose of patient lifting devices clashes with the nurses’ cultural emphasis on compassion, and with PT/OTs’ cultural emphasis on independence except when use increases patients’ independence.

Conclusions

Cultural expressions regarding the nature of care-giving among healthcare professionals may affect the propensity to adopt safety measures in complex ways. The workers’ understanding of the purpose of their work, and acceptable means of conducting it, should be understood before implementing safety interventions. The utilization of lift assist teams, who are not socialized into the cultures of nursing or PT/OT, may be one means of circumventing cultural barriers to lift equipment use.  相似文献   
600.
The education of safety professionals shows a high variety in their level of approved qualifications, ranging from a technician level up to university master courses, and more recently, doctoral programs. In European countries, it seems that there are some differences in what regards the characteristics of the courses. These may be due to national particularities and legal issues, but also to the nature of the institutions and people ‘behind’ the courses.This paper presents the results of a survey carried out in the scope of an European research project and it aims to provide a basic understanding of the range and diversity of the OHS post-graduation courses. With an estimated average answer rate of 50%, the survey has only included courses with more than 120 teaching hours, from a post-graduation level, and with complete programs. Results are presented for 90 courses, from 18 countries, mainly (84.4%) from universities.It is possible to highlight the fact that, as expected, the majority of the courses (59%) are Masters (or equivalent), and are organised primarily by Engineering, Applied Sciences and Management schools/faculties, which together accounted for nearly 65% of the courses. In what regards the adopted quality systems reported by respondents, there is a predominance (65.8%) of the use of “internal” tools, such as the students and teachers evaluations and internal audits.One of the main conclusions is that there is a large variability amongst the analysed courses. However, it should be emphasised that these results are not representative of the situation all around Europe, as it was not possible to obtain information from all OHS courses. Considering the identified differences within all the European countries, the harmonisation of post-graduation courses on OHS, if it is to occur, has a long way to go.  相似文献   
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