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基于项目多样性的农业机械化评价方法 总被引:1,自引:0,他引:1
农业机械化涉及因素众多、包含项目多样和地区间存在差异,使得农业机械化评价比一般概念的综合评价更为复杂.依据系统理论与方法,在全面认识农业机械化评价特点的基础上,明确了项目重要性是影响评价结果的因素之一,提出了基于项目多样性农业机械化评价的方法思想与技术路线.讨论了丘陵地区农业机械化所包含类别项目的一般层次结构,建构了农业机械化评价的程度度量和项目相对重要性衡量两套指标体系,阐明了农业机械化程度的计算方法,并在实际中加以应用,得到满意结果. 相似文献
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我国农业机械化发展水平评价指标体系构建与实证分析 总被引:4,自引:0,他引:4
我国农业机械化发展水平评价指标体系是由农业机械化装备水平、农业机械化作业水平、农业机械化系统体系3个层面所构建的,通过相关分析确定了各级评价指标的权重系数,建立了农业机械化发展水平综合评价模型,对2002年我国各地区农业机械化发展水平进行了测算与评价。 相似文献
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评价农业机械化发展水平是认识农业机械化的地位和作用、分析农业机械化发展状况、编制农业机械化发展计划以及促进农业机械化持续健康发展的需要,也是认识和评价农业现代化状况、进而推动农业现代化发展的需要.为此,对农业机械化的评价指标体系及评价标准进行了研究和论述. 相似文献
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我国农业机械化发展水平评价指标体系是由农业机械化装备水平、农业机械化作业水平、农业机械化系统体系3个层面所构建的,通过相关分析确定了各级评价指标的权重系数,建立了农业机械化发展水平综合评价模型,对2002年我国各地区农业机械化发展水平进行了测算与评价。 相似文献
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农业机械化发展水平评价的研究——以绍兴市为例 总被引:1,自引:0,他引:1
为加快绍兴市农业机械化发展,根据现有农业机械化水平评价指标体系,利用2000~2010年绍兴市农业机械化统计数据,测算了该市在此期间各年度的农业机械化发展水平.结果表明,目前绍兴市已处于农业机械化发展中级阶段的快速发展期.在此基础上,结合绍兴市农业生产实际,提出了推进绍兴市农业机械化发展的措施与建议. 相似文献
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我国农业机械化发展的阶段性研究 总被引:21,自引:0,他引:21
根据农业机械化发展阶段划分依据,提出了以农机作业为基础、能力为保障、效益为核心的农业机械化发展评价指标体系,建立了发展阶段模糊评判模型,运用此模型对我国及各地区农业机械化所处发展阶段进行了评判,并分析了各地农业机械化发展的状况. 相似文献
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科学发展农业机械化的模型体系 总被引:1,自引:1,他引:0
定量分析是认识与解决复杂系统问题的基础,应从不同的侧面建立相应的数学模型.为此,以科学发展观为指导,依据系统工程的理论与方法,在充分认识发展农业机械化所涉及的基本问题与模式求解过程的基础上,构建了定量分析科学发展农业机械化的问题结构和模型体系;分析了模型体系的结构关系和各个模型的作用及其数学方法;阐明了模型体系运行调试的基本方向-农业机械化发展的一般规律. 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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《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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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