区域经济系统的分形特征及模型研究

通过对区域经济系统模型的研究,确定了经济系统的分形特征,并通过实例建立投入与产出的数学模型,验证了其分形特征,利用分维确定了各投入与产出量的变化趋势,揭示了区域经济系统的复杂变化,为了解和指导区域经济发展提供了新的方法和依据。     

粮食生产的机械化问题

粮食牛产机械化是生产力发展的一个重要方而，也是一种必然趋势。机械化生产手段可以提高粮食产量，确保粮食生产持续发展，提高粮食生产效率和经济效益。粮食生产机械化不仅是农业技术变迁的一种自然发展过程，而且与制度变迁密切相关、互相促进。在粮食生产机械化中，有很多现实问题需要解决。     

我国谷物干燥机械的发展现状及对策

谷物干燥是粮食生产的重要步骤。我国是粮食生产和消费大国,因地制宜,大力发展谷物干燥机械,对于解决粮食生产过程中的损失和提高谷物品质有着极其重要的意义。为此,针对我国谷物干燥机械发展过程中存在的问题,提出了对策及建议,为我国谷物干燥机械的发展研究提供了参考依据。     

Cover crop evapotranspiration under semi-arid conditions using FAO dual crop coefficient method with water stress compensation

Cover cropping is a common agro-environmental tool for soil and groundwater protection. In water limited environments, knowledge about additional water extraction by cover crop plants compared to a bare soil is required for a sustainable management strategy. Estimates obtained by the FAO dual crop coefficient method, compared to water balance-based data of actual evapotranspiration, were used to assess the risk of soil water depletion by four cover crop species (phacelia, hairy vetch, rye, mustard) compared to a fallow control. A water stress compensation function was developed for this model to account for additional water uptake from deeper soil layers under dry conditions. The average deviation of modelled cumulative evapotranspiration from the measured values was 1.4% under wet conditions in 2004 and 6.7% under dry conditions in 2005. Water stress compensation was suggested for rye and mustard, improving substantially the model estimates. Dry conditions during full cover crop growth resulted in water losses exceeding fallow by a maximum of +15.8% for rye, while no substantially higher water losses to the atmosphere were found in case of evenly distributed rainfall during the plant vegetation period with evaporation and transpiration concentrated in the upper soil layer. Generally the potential of cover crop induced water storage depletion was limited due to the low evaporative demand when plants achieved maximum growth. These results in a transpiration efficiency being highest for phacelia (5.1 g m⁻² mm⁻¹) and vetch (5.4 g m⁻² mm⁻¹) and substantially lower for rye (2.9 g m⁻² mm⁻¹) and mustard (2.8 g m⁻² mm⁻¹). Taking into account total evapotranspiration losses, mustard performed substantially better. The integration of stress compensation into the FAO crop coefficient approach provided reliable estimates of water losses under dry conditions. Cover crop species reducing the high evaporation potential from a bare soil surface in late summer by a fast canopy coverage during early development stages were considered most suitable in a sustainable cover crop management for water limited environments.     

组合预测方法及其在粮食产量预测中的应用

提出了一种组合预测方法，以“预测偏差绝对值的和最小”为标准，用线性规划确定组合权系数的最优加权算法，对青海省的粮食总产量进行了预测分析。结果表明，此模型具有较高的精度。     

热泵式节能烘干机的设计

热泵是一种使热量从低温介质流向高温介质,以对高温物体进行供热的装置.为此,利用热泵原理研究设计了一种小型高效节能烘干机,并介绍了该机的主要特点、总体结构等,尤其对热泵、烘干床进行了详细介绍.该机具有结构简单新颖、造价低廉、使用寿命长、高效节能等优点,不仅可以烘干多种农产品,还可以烘干茶叶、蘑菇等多种农副产品.     

我国粮食仓储技术的概况与发展

粮食安全储存是个世界性难题,如何发展、提升和完善粮食仓储技术是我国政府面临的一项亟待解决的课题.为此,在提出粮食仓储技术内涵的基础上,首先概述总结了我国粮食仓储设施及方式的发展历程;其次在分析国内储粮技术研究发展现状的基础上,重点介绍了低温储粮、气调储粮两种绿色环保型储粮技术及计算机技术在仓储上的应用;论述了我国仓储设备的整体发展现状;最后指出了我国仓储技术的存在的问题与发展趋势.     

玉米籽粒内部组分低对比度透射图像精确分割研究

为解决玉米籽粒透射图像由于对比度较低造成内部组分提取不精确的问题,提出一种基于色彩通道非线性变换的多通道重叠区域分割方法,对玉米籽粒图像在灰度、R通道及b通道下得到的二值图像使用重叠区域原理,实现玉米籽粒组分的精确分割。首先,采集不同玉米品种的籽粒透射图像,提取单粒玉米籽粒;其次,采用多通道重叠区域法分割单粒籽粒图像,得到玉米籽粒胚部、角质胚乳和粉质胚乳3部分的图像;最后,以查全率和查准率评价多通道重叠区域法与传统图像分割方法对不同品种玉米籽粒的分割效果。不同品种玉米籽粒的分割试验表明:多通道重叠区域分割方法的查全率、查准率及综合评价指标均达到98%以上,分割效果优于传统的图像分割方法,能够实现不同品种透明角质玉米籽粒透射图像的精确组分分割。     

智能粮食水分测试仪的研制

给出以AT89C52单片机为核心的粮食水分测试仪的硬件结构组成,并详细介绍了信号处理和测量方法;通过对传感器的标定并进行相应的数据处理。通过实验发现,该仪器使用方便,测量精度高。     

知识产权对接中小企业模式研究

知识产权是企业核心竞争力的重要来源,特别是中小企业发展壮大的有效手段,因此中小企业亟须提升知识产权创造、运用、保护和管理能力.实施中小企业对接知识产权模式的有效途径是:企业进一步提高对知识产权的认识与自主创新能力,加快知识产权人才培养;同时政府要在知识产权交易、服务、运用和产权保护等方面发挥主导作用.