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Escaping is natural in the case of accidents in underground mines. Determining the optimal escape route is one of the most important factors for relief of miners in the emergency cases. This paper aims at developing a mathematical method to determine the shortest escape time from a given point to alternative points of an underground mine network. It also aims to find the shortest routes between each pair of the given points. The first point refers to the place of the accident where some miners may exist, and the alternative points show the safe places that the miners can escape to. After determining the shortest escape time and its corresponding route between each pair of mine work junctions, it is possible to set an electronic board that shows the access route to the nearest safe location by an arrow sign in each mine work. In this paper, Floyd–Warshall and π algorithms are used to determine the shortest escape time between the place of accident and safe places as well as their corresponding routes. Those algorithms are rigorous since they are supported by mathematical proof. Finally, the algorithms are implemented on the network of a certain underground coal mine and the results are presented. 相似文献
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Environmental Modeling & Assessment - Soil salinity and alkalinity seriously threaten crop production, soil productivity, and sustainable agriculture, especially in arid and semi-arid areas,... 相似文献
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Farideh Sadeghian Amir Kasaeian Pirasteh Noroozi Seiyed Hassan Taiebi 《International journal of occupational safety and ergonomics》2013,19(2):355-361
Musculoskeletal disorders (MSDs) are an important health problem among healthcare workers, including clinical laboratory ones. The aim of the present study was to investigate the prevalence of MSDs and individual and psychosocial risk factors among clinical laboratory workers. A cross-sectional study was carried out among 156 workers of 30 clinical laboratories in 3 towns of Iran. The Nordic questionnaire with individual and psychosocial risk factors was used to collect data. Multiple logistic regression analysis was performed. The prevalence of reported MSDs among the study population was 72.4% in the past 12 months. The most prevalent MSDs were pain in the lower back and neck; 42.7% and 33.3%, respectively. Significant relations were found between MSDs and age, gender, heavy work at home and job control (p < .05). MSDs among laboratory workers were high and associated with age, gender, heavy work at home and job control. More research into measuring these factors and workplace physical demands is suggested. 相似文献
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Allahkarami Ebrahim Azadmehr Amirreza Noroozi Fahimeh Farrokhi Shayan Sillanpää Mika 《Environmental science and pollution research international》2022,29(32):48438-48452
Environmental Science and Pollution Research - This research aimed to develop a novel composite as a low-cost adsorbent for the removal of nitrate ion from aqueous solutions. The characterization... 相似文献
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