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951.
Dissipation behaviour of endosulfan and dichlorvos in/on cauliflower, variety Snowball-16, was studied during rabi season (Sep.–March) 2003–2004. Endosulfan and dichlorvos were sprayed @ 350 and 110g a.i. with 115 g a.i., respectively, 80 days after transplanting. Samples were taken at the interval of 0 (1h after spray), 3, 5, 7, and 10 days after spray (DAS) in triplicate and residues were estimated on GC-ECD system equipped with capillary column. The initial deposits of 3.452 and 0.295μgg−1 of endosulfan and dichlorvos dissipated to 0.084 (97.56%) and 0.009 (96.95%), respectively after 10 DAS. Residues of endosulfan reached below maximum residue limit of 2μgg−1 one day after spray and of dichlorvos were below MRL value of 0.5μgg−1 even on 0 day. Dissipation pattern followed first order kinetics for both the insecticides with half life periods of 1.81 and 2.08 days for endosulfan and dichlorvos, respectively.  相似文献   
952.
新疆番茄酱企业生产废水处理利用方式探析   总被引:4,自引:0,他引:4  
近年来,新疆番茄酱加工业得到了迅速发展,目前番茄酱的产销量已占全国的90%以上。与此同时,新疆番茄酱生产企业的废水排放量也大幅增加,大量未经处理的废水直接排放,已对当地的水环境构成严重的污染隐患。本文分析了新疆番茄酱企业生产废水的排放特征与目前排放出路的可行性,并结合新疆的自然地理条件及番茄酱企业的分布情况,着重探讨了土地处理这一适合新疆的废水利用方式,以期有利于新疆的环境保护和废水资源的循环利用。  相似文献   
953.
Objective: The overrepresentation of young drivers in poor road safety outcomes has long been recognized as a global road safety issue. In addition, the overrepresentation of males in crash statistics has been recognized as a pervasive young driver problem. Though progress in road safety evidenced as a stabilization and/or reduction in poor road safety outcomes has been made in developed nations, less-developed nations contribute the greatest road safety trauma, and developing nations such as Colombia continue to experience increasing trends in fatality rates. The aim of the research was to explore sex differences in self-reported risky driving behaviors of young drivers, including the associations with crash involvement, in a sample of young drivers attending university in Colombia.

Methods: The Spanish version of the Behaviour of Young Novice Drivers Scale (BYNDS-Sp) was applied in an online survey to a sample of 392 students (225 males) aged 16–24 years attending a major university. Appropriate comparative statistics and logistic regression modeling were used when analyzing the data.

Results: Males reported consistently more risky driving behaviors, with approximately one quarter of all participants reporting risky driving exposure. Males reported greater crash involvement, with violations such as speeding associated with crash involvement for both males and females.

Conclusion: Young drivers in Colombia appear to engage in the same risky driving behaviors as young drivers in developed nations. In addition, young male drivers in Colombia reported greater engagement in risky driving behaviors than young female drivers, a finding consistent with the behaviors of young male drivers in developed nations. As such, the research findings suggest that general interventions such as education, engineering, and enforcement should target transient rule violations such as speeding and using a handheld mobile phone while driving for young drivers in Colombia. Future research should investigate how these interventions could be tailored specifically for the Colombian cultural context, including how their effects can be evaluated, prior to implementation.  相似文献   

954.
Introduction. Most work-related musculoskeletal disorders (MSDs) are associated with improper postures and poorly designed workstations. This study is an attempt to examine the prevalence and severity of MSDs as well as anthropometric dimensions among city bus drivers. Methodology. This cross-sectional study was carried out on 60 male bus drivers. A body discomfort chart was used to evaluate MSDs. Spearman correlation was employed to examine the relationship between body size and the severity of discomfort. Results. Data analysis showed that discomfort reported in the lower back (33.3%), upper back (18.3%) and knee (15%) was severe and there was a direct and significant correlation between the body mass index and the severity of discomfort in the shoulder, arm and hip (p?p?Conclusion. The results of the study can be used to address ergonomic risk factors and reduce their associated disorders. The findings of the study can be used in training programs to educate drivers how to decrease the risk associated with work-related MSDs by adopting appropriate behavior strategies.  相似文献   
955.
Abstract

Objective: The current study investigated whether older drivers’ driving patterns during a customized on-road driving task were representative of their real-world driving patterns.

Methods: Two hundred and eight participants (male: 68.80%; mean age?=?81.52 years, SD?=?3.37 years, range?=?76.00–96.00 years) completed a customized on-road driving task that commenced from their home and was conducted in their own vehicle. Participants’ real-world driving patterns for the preceding 4-month period were also collected via an in-car recording device (ICRD) that was installed in each participant’s vehicle.

Results: During the 4-month period prior to completing the on-road driving task, participants’ median real-world driving trip distance was 2.66?km (interquartile range [IQR]?=?1.14–5.79?km) and their median on-road driving task trip distance was 4.41?km (IQR?=?2.83–6.35?km). Most participants’ on-road driving task trip distances were classified as representative of their real-world driving trip distances (95.2%, n?=?198).

Conclusions: These findings suggest that most older drivers were able to devise a driving route that was representative of their real-world driving trip distance. Future research will examine whether additional aspects of the on-road driving task (e.g., average speed, proportion of trips in different speed zones) are representative of participants’ real-world driving patterns.  相似文献   
956.
Objective: The present research relies on 2 main objectives. The first is to investigate whether latent model analysis through a structural equation model can be implemented on driving simulator data in order to define an unobserved driving performance variable. Subsequently, the second objective is to investigate and quantify the effect of several risk factors including distraction sources, driver characteristics, and road and traffic environment on the overall driving performance and not in independent driving performance measures.

Methods: For the scope of the present research, 95 participants from all age groups were asked to drive under different types of distraction (conversation with passenger, cell phone use) in urban and rural road environments with low and high traffic volume in a driving simulator experiment. Then, in the framework of the statistical analysis, a correlation table is presented investigating any of a broad class of statistical relationships between driving simulator measures and a structural equation model is developed in which overall driving performance is estimated as a latent variable based on several individual driving simulator measures.

Results: Results confirm the suitability of the structural equation model and indicate that the selection of the specific performance measures that define overall performance should be guided by a rule of representativeness between the selected variables. Moreover, results indicate that conversation with the passenger was not found to have a statistically significant effect, indicating that drivers do not change their performance while conversing with a passenger compared to undistracted driving. On the other hand, results support the hypothesis that cell phone use has a negative effect on driving performance. Furthermore, regarding driver characteristics, age, gender, and experience all have a significant effect on driving performance, indicating that driver-related characteristics play the most crucial role in overall driving performance.

Conclusions: The findings of this study allow a new approach to the investigation of driving behavior in driving simulator experiments and in general. By the successful implementation of the structural equation model, driving behavior can be assessed in terms of overall performance and not through individual performance measures, which allows an important scientific step forward from piecemeal analyses to a sound combined analysis of the interrelationship between several risk factors and overall driving performance.  相似文献   

957.
Abstract

Objectives: 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   
958.
为了更准确地预测职业病,在传统GM(1,1)模型的基础上,提出改进的非线性GM(1,1)模型,在传统的GM(1,1)模型中引入弱化算子,将紧邻均值与原始数据之间的线性假设改为非线性假设,提高曲线的拟合度。以2005—2014年的全国职业病例数为研究对象,进行数据拟合和预测分析,其中以2014年职业病例数作为验证数据,并利用后验差比值和小误差概率2个参数,检验该改进模型的预测精度。由应用实例的分析结果可知:在职业病发病趋势的预测方面,改进的非线性GM(1,1)模型的预测精度提高到一级,曲线拟合度较高,预测得到2015年的职业病例数为34 900例。  相似文献   
959.
为了提高管网地震监测点布局的准确性和合理性,基于管网微观水力计算模型和动态分级法,提出供水管网震后流量监测点的动态分级优化布局模型。首先,利用管网微观水力计算模型计算管段流量的影响系数,构建管段的影响系数矩阵,并利用信息熵确定管段权重;其次,标准化处理影响系数矩阵,通过聚类迭代提出供水管网地震流量监测点优化布局的动态分级方法,对供水管网震后流量监测点进行优化布置分级评定;最后,根据工程实例进行方法实践,结果表明:供水管网中的管线分类较为科学合理,地震监测点在供水管网上分布也比较均匀,而且该模型在一定程度上消除了人为因素的影响,保障了震时管网的监控效果和日常建设的合理性。  相似文献   
960.
为促进安全管理,提高效率与效果,对基于情感思维的安全管理进行研究,将情感思维融于安全管理,基于情感思维的定义、内涵及功能,具体分析安全管理中情感思维的功能及其功能综合作用,建立安全管理中情感思维功能作用理论模型;根据该理论模型分析情感思维驱动力及强化作用及其对安全目标实现的影响;建立基于情感思维的安全管理设计模式,最后提出优化安全管理的措施与方法,以促进安全管理的实施。研究表明:基于情感思维的安全管理研究,能较好地体现安全管理人本原理,发挥情感的能动作用,将理性融入其中与情感进行平衡,实现安全管理的优化。  相似文献   
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