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81.
高速公路监控系统正日益成为高速公路日常运营管理的一个重要手段,发挥着重要的作用。其主要是通过道路监控摄像机作为视频图像采集系统进行监控的。该文在分析高速公路监控需求的基础上,阐述了对高速公路监控摄像机的性能要求,以及进行监控摄像机的选择时需要考虑的因素。 相似文献
82.
2009~2010年婺源县主栽早稻品种稻瘟病的抗性监测 总被引:2,自引:1,他引:1
婺源县为江西省稻瘟病的常发区和重发区。2009~2010年分3批播种(间隔期5 d),评估婺源县9个主栽早稻品种对水稻稻瘟病的抗性。结果表明,两年中,株两优02和株两优09对叶瘟的抗性均保持中抗,陆两优996、淦鑫203、T优898和春光1号为中感,抗性改变的品种有3个,其中金优463由中抗变为高感,金优458和先农37号均由感病变为高感。两年中,株两优02、淦鑫203和株两优09对穗瘟的抗性均保持中抗以上,陆两优996、T优898为中感,春光1号为高感,抗性改变的品种有3个,其中金优463由中感变为高感,金优458和先农37号均由感病变为高感。在以上9个品种中,只有株两优09和株两优02对叶瘟和穗瘟的抗性两年中均保持在中抗以上。 相似文献
83.
对京承农业走廊区域内空间信息资源管理、农产品供求、观光农业、农业技术推广、土地利用监测和农业生态评价等方面的问题进行深入分析研究,运用网络地理信息技术,建立基于WebGIS的都市型现代农业走廊网络服务系统。系统包括走廊管理、园区动态、技术示范、供求信息和观光农业等模块,采用土地利用动态变化、生态服务价值量和景观生态丰度等模型,对京承农业走廊内的土地利用变化、景观和生态效益进行分析评价,解决了上述在农业走廊区域内农业发展转变过程中所要面临的问题;系统化地构建了为农民、消费者、经销商和管理部门等提供信息、技术和服务的网络平台,以提高都市型现代农业的科学化管理、规划和实施水平。 相似文献
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A comparison of monitoring systems used for Ceratitis species (Diptera: Tephritidae) in South Africa
For 16 years a bucket-type trap known as the Sensus fruit fly trap has been used to monitor three fruit fly pest species Ceratitis capitata, Ceratitis rosa and Ceratitis cosyra in South African fruit industries. The relative efficiencies of lures sold for monitoring fruit flies with the Sensus trap in South Africa were determined in field experiments where laboratory-reared C. capitata, C. rosa and C. cosyra were released in a mango orchard within a few metres of Sensus traps containing either Capilure (trimedlure or tert-butyl 4 (or 5) -chloro-2-methylcyclohexane carboxylate), Ceratitislure (protein hydrolysate plus β-caryophyllene) or Questlure (protein hydrolysate plus plant extracts). When using 12-day-old flies, Capilure caught 3 times more C. capitata males than C. rosa males and this difference was more extreme when 3-day-old flies were released. Ceratitislure caught significantly more 12-day-old C. cosyra males than 12-day-old C. capitata males, but the difference was reversed when 3-day-old flies were compared. Questlure showed the least differences between species and age but recovered the lowest proportion of released species. Further comparisons were conducted in an orchard with wild flies using other known attractants in larger yellow Probodelt bucket traps. Capilure caught more male C. capitata than BioLure Fruit Fly 3-component, but BioLure 2-component (trimethylamine and ammonium acetate) was more effective than Questlure for C. capitata females. The 3-component lure was also more effective than both Capilure and Questlure for male and female C. rosa, respectively. Ceratitislure was the most effective lure for male C. cosyra flies and BioLure 3-component was more effective than Ceratitislure and Questlure for female C. cosyra flies. The intervention threshold of 4 flies/trap/week previously used in citrus with Capilure for C. rosa was lowered to 2 C. rosa/trap/week when using the Sensus trap due to the lower sensitivity of this trap-lure combination found for C. rosa in this study. The 3-component lure, or the 2-component combination of trimethylamine and ammonium acetate in a ratio of 1:8 in the Sensus trap capsule, would be more effective for both sexes of all three Ceratitis species than the Questlure that is currently being used. 相似文献
86.
Attractants and pheromones are commonly used in integrated pest management programs in crop systems. However, pheromone dispensers employed in monitoring traps and lure and kill devices are not usually well studied and attractants are released at uncontrolled rates leading to low treatment efficacies and misleading monitoring estimations. Fruit flies are pests of economic importance and monitoring is essential in order to program insecticidal treatments. Moreover, lure and kill techniques are being increasingly used, but the cost of these techniques depends on the number of required traps and, therefore, on the efficacy of the attractants. Ceratitis capitata and Bactrocera oleae are the two main fruit flies in Mediterranean countries, and the effect of different doses of trimedlure and spiroacetal on fly attraction has been studied. Results showed that a release rate over 1.28 mg/day of spiroacetal reduces B. oleae attraction and emission values over 2.4 mg of trimedlure per day did not increase C. capitata catches. Under the environmental conditions of our study, an optimum release rate for pheromone attraction in B. oleae was determined. Emission values over this optimum level reduced B. oleae attraction. However, when a parapheromone was used with C. capitata, a fruit fly of the same family, the optimum emission value was not found and higher quantities of parapheromone attracted the same number of flies. The saturation effect of high concentrations of pheromone and parapheromone is discussed. 相似文献
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89.
针对我国上市公司内部监督机制存在的问题分析的独立董事监督机制现状以及失效的原因,并对独立董事监督机制有效性进行了研究,给出五个基本假设,采用我国上市公司的相关数据作为样本进行的实证研究,结果发现次级委员会设置是影响上市公司独立董事内部监督是否有效的因素,并且呈正相关。 相似文献
90.
基于RS林地退化监测技术 总被引:2,自引:0,他引:2
以永安市、连城县、漳平市为研究区域,选择林地土层厚度、林地土壤侵蚀、林地有机质、全氮、全磷、全钾、森林气候生产力、森林生产力等因子,应用层次分析法,构建林地退化评价指标体系。通过RS技术提取各指标专题信息,生成林地退化图。结果表明,研究区无退化林地面积289 204.20 hm2,轻度退化面积264 772.24hm2,中度退化面积142 851.71 hm2,严重退化面积60 473.69 hm2,剧烈退化面积139.99 hm2,分别占总面积的38.18%、34.96%、18.86%、7.98%、0.02%;3县(市)中永安市林地状况最好,漳平市次之,连城县最弱;研究区林地退化状况总体良好。 相似文献