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大面积喷洒农药不仅造成了农药的大量浪费，而且严重地污染了环境，同时，农药在作物中的残留威胁着人类的健康生活。因此，利用机器视觉识别出杂草并实现农药自动喷洒的定量定点化成为精细农业研究的重点。其中，将作物和杂草从数字图像中快速准确地分离出来，对后续杂草识别处理以及实现定量定点喷洒农药具有重要意义。 相似文献
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无人机农药喷洒与人工作业的比较试验 总被引：1，自引：0，他引：1
针对当前农业喷洒技术发展的特点及农药喷洒方式的转变,简要分析了人工农药喷洒技术、无人机农药喷洒技术控制原理及软硬件配置和关键技术参数,并通过两者的对比试验做出客观评价。结果表明:无人机农药喷洒技术与传统人工喷洒作业相比,具有明显的优势性,该技术在精准农业发展中具有十分重要的应用推广价值,应成为我国农业发展创新的一股重要推动力量。此对比试验可为深入研究无人机喷洒技术、实现科技兴农提供一定参考。 相似文献
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目前化学农药大量应用于农业生产中，农药在农业的增产增收、预防病虫害、去除杂草等方面，都有着重要作用。同时，农药的大量使用也产生了一些不容忽视的副作用。如农药通过喷洒直接污染农作物，或通过受污染的水体、土壤及环境，间接污染其它食物而造成农药中毒等。一、... 相似文献
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近几年来，一些发达国家为提高农药喷洒的效率和减少农药喷洒时对人体的伤害，农药喷洒机械正趋向自动化。 韩国的泰仁技术开发公司，经过两年多时间的研究，开发研制成功一种无人农药喷洒机。这种无人农药喷洒机的核心部件，是喷洒农药的喷头。它由电子精密陶瓷制成，具有电动控制功能，能将农药自动均匀地喷洒到农作物叶片的两面，达到理想的杀虫效果。用于温室、塑料大棚和果树林等地的杀虫作业时，可安装在轨道上，用蓄电池驱动，实施无人喷洒作业。这不仅能省时、省力、省农药，而且还可避免农药对人体的伤害，十分安全。 美国斯坦福大… 相似文献
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目前,我国在农业生产中对虫害的防治主要是采用喷洒农药的方式,该方式虽然能够起到控制、消除虫害的作用,但也造成了土壤、地下水、空气的污染和农作物的农药残留,直接威胁到人们的生存环境和身体健康。长期大量地施用农药还会导致害虫产生抗药性,从而迫使农户加大农药的施用量,进而陷入不断加大用药量、不断加剧环境污染的恶性循环中。另外,喷洒农药的农机具往往采用小型电机或小型汽油机为动力 相似文献
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传统农田病虫害防治是通过人工作业进行农药喷洒,农药一般只存留在农作物的顶部,难以对农作物下部产生作用,影响了农作物病虫害防治效果,降低了农作物的产量和经济效益。而植保无人机在农田病虫害防治中具有可控制农药用量、提高农业机械化水平、降低农户用药成本、人工操作便捷等优点。基于此,笔者在分析农作物植保无人机的应用优势的基础上,剖析了其喷洒作业地形要求、节药节水要求及全面植保方案要求,提出了提高植保无人机保有量、开发专业化喷洒药剂、加强政策引导、加快行业标准制定、强化操纵队伍建设等建议,探讨了农作物植保无人机的具体应用前景。结果表明,植保无人机可在不同施药要求的环境下进行低空喷洒作业,作业效率高,可提高农药喷洒效率,减轻了人工作业强度,降低了生产成本,提高了农户收益。 相似文献
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《Journal of Agricultural Engineering Research》1998,69(3):249-254
A model to represent the discolouration of dried powder of carrots as a function of temperature was developed. Two types of carrots, Asian and European, containing large amount of lycopene and β-carotene, respectively, were tested. The dried powder was stored under an atmosphere with O2and at three different temperatures, 5,20 and 35°C. The surface colour of the powder was monitored during storage by a Hunter colour ratioa/b. In the proposed model, the rate of oxidation was assumed to be represented by the product of the fraction of concentration of oxidized pigment at arbitrary time and a specific rate of oxidation of pigment. The rate parameters in the proposed model were calculated by fitting the experimental data with smooth curves by trial and error at the end of the induction period but before discolouration took place. The frequency constant and activation energy, expressing the temperature dependence of the rate parameters, were expressed by the Arrhenius relation. The simulation results of a Hunter colour ratioa/bof dried powder at 25°C showed good agreement with the experimental data, suggesting that the proposed model was effective for the prediction of discolouration of dried powder of both types of carrot. The use of the induction period in the manner described may enable the shelf life of dried powder to be predicted. 相似文献
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感官检验棉花的品级,这是农村常见的一种检测手段.它的一个主要特点就是存在不确定性.这是由于检验员的品级检验水平存在一定的差异,其中有很多因素制约着检验的结果.文章对影响感官检验结果的因素进行了系统的分析. 相似文献
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从灾害经济学的角度探讨了城镇供水优化调度的必要性和可能性，认为在缺水不可避免的情况下，对供水进行优化调度可以减小缺水带来的损失，产生较好的减灾效益，特别是可以大大减小严重干旱的灾害效应。并根据水资源的特性，提出了缺水损失的计算模式以及优化调度的原则和方法。 相似文献
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The fractional outflow rate of water from the rumen, measured as the rate of disappearance of the chromium complex of ethylenediamine tetra-acetic acid, was related to a number of dietary factors. A multiple regression equation was derived which expressed fractional outflow rate as a function of the intakes of dry matter, ash, acid-detergent fibre and crude protein.The data analysed consisted of 243 observations for sheep on 59 diets, including forage, concentrate and mixed diets. The ranges covered by the data were: fractional outflow rate 0.7–3.6 day?1; dry matter intake 560–1400g/day; ash 4–30%, acid-detergent fibre 7–41%, crude protein 5–26 % of dry matter; there were no observations for sheep of less than 34 kg liveweight.The equation accounted for 56·3 % of the total variance. Between-sheep variance could not be calculated for the whole of the data but was undoubtedly substantial since, for a sixth of the data, it was known to account for 38 % of the total variance. 相似文献