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41.
F. Lebeau A. VerstraeteC. Stainier M.-F. Destain 《Computers and Electronics in Agriculture》2011,77(2):161-174
A spray drift model called RTDrift was developed to estimate drift caused by ground sprayer machines. The sprayer was equipped with sensors measuring operational parameters namely spray pressure, boom height and movements, and geolocalisation. Climatic parameters, including wind speed and direction, were measured using a 2-D ultrasonic anemometer mounted on the sprayer. The nozzles spray drop size spectra were characterised using Phase Doppler Interferometer measurements. At every successive boom position, a diffusion-advection Gaussian tilted plume model computed the spray drift deposits for each drop class taking into account evaporation. The contribution of a single nozzle was calculated by integration of the individual puffs with respect to time and summation of the contributions of individual drops classes. The overall drift generated by the sprayer machine was obtained adding the contributions of all the nozzles. Field trials were performed on a fallow field with water and on crops with pesticides in various wind conditions. The ground drift was measured at different drift distances using fluorometric methods. When comparing the results of the model with experimental measurements of deposits, the model produced realistic maps of drift deposits. Some further improvement is needed in the presence of large scale eddies. The model offers potential benefits for the farmer as a real time drift estimator embedded on a sprayer machine. 相似文献
42.
赵永胜 《农业图书情报学刊》2011,23(5):17-20,27
创意农业是一项综合性的系统工程,也是对传统农业发展模式的一种创新。在分析主要发达国家创意农业模式、我国创意农业发展现状和山西省创意农业发展状况的基础上,提出了山西省创意农业发展对策建议。 相似文献
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海南民营橡胶产业现状及发展对策 总被引:1,自引:0,他引:1
简要介绍了海南省民营天然橡胶种植历史,从种植、加工、销售和对农民的增收作用等4个方面概述了海南民营天然橡胶发展现状,剖析了海南民营天然橡胶产业中的优势和存在的主要问题,提出了海南民营天然橡胶发展对策。 相似文献
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Quantitative, qualitative and phenotypic body measurements were determined on Longling Yellow goats in Longling of Yunnan Province in China. Body weight was determined at birth and then at 3, 6, 9, 12, 18, 24, 36, and 48 mon of age. Body measurements traits including height at wither (HW), body length (BL), heart girth (HG), chest depth (CD), and circumference of cannon bone (CCB) were determined at 3, 6, 9, 12, 18, 24, 36, and 48 mon of age. Phenotypic traits including coat colour, horns type, tip horn torsion, nose type, hair on forehead, wattles, ear lobes, black back line, hair on legs, and black hair on belly were determined at 12, 18, 24, 36, and 48 mon of age. Males were heavier (P〈0.01 or P〈0.05) than females; and except for chest depth at 24 mon of age (P 〉 0.05), all other body measurements were also higher (P 〈 0.01 or P 〈 0.05) in males. HW, BL, CD, HG, and BW increased (P 〈 0.01) with age, except for 48 mon of females (P 〉 0.05); while CCB did not always increase with age. HG had the highest correlation (P〈0.01) with body weights of both sexes. No differences were observed between the two sexes in the colour of the coat, horn type, tip horn torsion, nose type, ear lobes, black back line, and black hair on belly. However, differences exist between the two sexes in the presence of hair on forehead, wattles and long hair on legs. The female goats absence of tip horn torsion had positive effect on all variables measured at 36 and 48 mort of age (P〈0.01 or P〈0.05). The presence of wattles was associated with heavier body weights from 18 mort (P〈0.01) of age onward, and also with longer HW, BL and CD (P〈0.01 or P〈0.05) in female goats. Female goats with ear lobes had heavier body weights at 12, 36 and 48 mon (P〈0.01) and longer CCB at 12 and 24 mon of ages (P〈0.05). Hair on legs and black hair on belly only had partly effect body measurements on 12 mon of Longling Yellow female goats. Results of this study provide valuable information that will assist breeders and genetic improvement specialists when conducting selection and preservation programs in Longling Yellow goats in China. 相似文献
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发酵测控系统是发酵过程参数智能检测与优化调控的基础,直接影响着发酵过程的控制性能。该文针对L-乳酸发酵过程的智能检测,提出了一种基于智能检测的发酵过程测控系统集成方法,给出了系统的体系结构及实现方法,集成了基于虚拟仪器技术的PXI总线发酵过程智能测控系统,给出了系统的软、硬件设计。该系统通过建立软测量模型,有效地实现了发酵过程不易测量参量的在线估计与控制,为发酵过程提供了一种新的测控系统。试验研究表明,将该系统应用到L-乳酸发酵过程中,通过在线估计葡萄糖液消耗量,实现了L-乳酸发酵过程补料优化控制,乳酸产量提高23%,提高了发酵产物得率。 相似文献
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为了分析植物器官体温形成机制的需要,即在植物与环境间热平衡分析时,有准确的植物器官热容量参数,该文采用热平衡法测定了番茄叶片和果实的热容量参数。考虑胁迫生态环境植物传热分析问题,也选择了侧柏等生态恢复先锋树种,以及作为参照的肉质植物芦荟的热容量参数。结果表明,番茄叶片热容为3253.7±97.10J/(kg℃),与针叶植物侧柏和肉质叶植物芦荟叶片的热容相近;番茄果实热容为3517.4±68.50J/(kg℃)。热平衡法可以用来测定植物器官的热容量;其热容量均低于水的热容量。对前人用热平衡法测定生物质热物性参数的方法,进行了改进和完善。该文既为其他生物质的热容量测定提供了试验方法,也为植物气候空间研究提供了热物性参数基础数据。 相似文献
50.
为方便测量不同喷雾条件下雾滴粒径大小,该文设计了喷头位置、喷雾角度、喷雾压力和风速大小等试验条件可精确调节的风送喷雾雾滴粒径测量系统。该系统喷头xyz三维空间位置调节范围分别为0~0.9、0~0.8和0~0.7m,调整精度为±0.04mm;喷雾角度调节范围为0~360°,调整精度为±0.005°;喷雾压力调节范围为0.2~0.5MPa,相对误差不大于1.5%;风速调节范围为0~15m/s,相对误差不大于4.17%。雾滴粒径风速影响特性试验表明,常用的3个粒径统计项D32、D43和DV0.5随风速增加而增大,其平均变化率分别为2.62、3.59和6.83μm·s/m,速度从3m/s增加到15m/s时,三者分别增加46%、26%和71%;雾滴粒径喷雾压力影响特性试验表明,D32、D43和DV0.5随压力增加而减小,其平均变化率分别为90.33、232.3和300.2μm/MPa,喷雾压力从0.2MPa增加到0.5MPa时,三者分别减小31%、36%和56%,表明风速和喷雾压力对雾滴粒径影响较大,在喷雾系统中进行风速和压力选择时需着重考虑其对粒径变化的影响。 相似文献