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201.
吴浩 《农业装备与车辆工程》2014,(8):39-41
汽车车内由于CO导致的意外安全事故常常被忽略。汽车发动机和空调在运行过程中产生的CO进入车内,极易被忽视而诱发中毒的事故。利用单片机传感器技术设计一种汽车车内CO浓度监控系统,当车内CO浓度达到200 ppm时系统发出第一次报警,当车内CO浓度达到300 ppm,系统发出第二次报警提示,并开启天窗通风,保证车内人员安全。 相似文献
202.
农业职业教育是服务"三农"的教育。针对农村剩余劳动力提出农民学分制学历教育培养模式,将课堂搬到"田间地头",最大限度地发挥农业职业学校服务于经济社会的职能,结合教育与生产实际,融合专业与产业,实现让广大农民接受教育的目标。 相似文献
203.
204.
食品安全是天大的事,培养相关的专业人才尤显重要。依据食品质量与安全专业人才培养目标要求明确专业内涵,采用模块设计方法构建食品质量与安全专业课程体系,并就如何提高人才培养质量提出建议。 相似文献
205.
王淑艳 《吉林农业科技学院学报》2014,(1):52-54
随着网络教育的发展,接受网络教育和考试认证的人越来越多,在线考试正在得以迅速发展.本文简要介绍在线系统工作原理和系统配置. 相似文献
206.
The Danish decision support system Crop Protection Online (CPO) optimises herbicide weed control. CPO recommends specific herbicide solutions to achieve a required level of control. The aim is to apply herbicides as little as possible but as much as necessary. CPOWeeds is a version of CPO adjusted to conditions in North-eastern Spain. The predicted efficacies and the yield obtained with CPOWeeds were validated in winter cereal field trials from 2010 to 2013. All CPOWeeds treatments were related to the efficacies obtained with standard herbicide treatments decided upon by local advisors. The predictions from CPOWeeds were compared to the actually achieved efficacies in the field trials for the nine weed species at different developmental stages and for 84.2% of the comparisons the obtained efficacies were equal to or higher than predicted. The average difference between predicted and observed efficacies was 2.35 percentage points. Yield was measured in three trials and the recommendations from CPOWeeds were maintaining yield. There were two situations where CPOWeeds were performing suboptimal. One is in the early weed growth stages, as the model is not yet prepared to account for water stress on root action herbicides applied at 10-11 BBCH. The second situation was in fields with a prior unidentified population of resistant Alopecurus myosuroides. For key species in winter cereals in Spain, such as Avena sterilis, Lolium rigidum and Papaver rhoeas, CPOWeeds achieved a satisfactory control level. It was concluded that the use of CPOWeeds allowed optimisation of the herbicide application with a very high robustness. The recommendations were satisfactorily for the conditions of the Northeast of Spain and have the potential to decrease the amount of applied herbicides by at least 30%. Therefore, it can be an important tool in Integrated Weed Management. 相似文献
207.
指出了中国正处在快速城市化的阶段,绿色社区开发已成为广泛关注的议题。以上海城市最佳实践区为例,通过对LEED-ND认证指标体系的分析,探讨了在LEED-ND认证体系驱动下,城市最佳实践区在场地规划、建筑节能、可再生能源和水资源利用等方面采取的开发策略和应用的绿色技术,以期为未来绿色社区的开发建设提供参考。 相似文献
208.
209.
Urban heat island (UHI) often cause negative impact and has been linked to heart stroke rate, morality, human comfort, energy consumption and air pollution. Fortunately, urban green spaces have been considered as an effective element to mitigate UHI through their cooling effect. However, further empirical research is necessary in order to efficiently guide the design and planning of urban green space. We observed the impacts of urban park's tree, grass and waterbody on microclimate inside the Olympic park of Beijing during summer days. The results indicated that, on average, the park was 0.48–1.12 °C cooler during the day, as well as increased air humidity 2.39–3.74% and reduced human comfort index 1.02–2.43 to generate more comfortable thermal environment. Urban park's cluster trees with short ground vegetation generated higher cooling effect than single trees, grass and waterbodies; proper irrigation regime enhanced the cooling effect of grasses, even the irrigated grass have similar cooling effect with small waterbody on sunny, windless summer days. Therefore, we advise to increase undergrowth coverage and grass irrigation management in order to take advantage of cooling effect of urban parks. 相似文献
210.
福建南平市竹产业标准体系实施、评价与改进建议 总被引:2,自引:2,他引:0
推动竹产业高质量发展,标准化工作任重道远,推进标准体系有效实施、开展标准体系评价、动态优化标准体系必不可少。本文以南平市竹产业为例,探索竹产业标准体系实施、评价与改进的方法,以期逐步建立福建省竹产业标准体系实施与评价体系。 相似文献