农业信息化背景下光伏发电扶贫模式及效益提升机制研究

精准扶贫已进入攻坚克难的决胜时期,光伏扶贫作为精准扶贫工程之一,在解决脱贫问题中发挥重要作用。农业信息化是促进贫困地区实现农业现代化的重要手段,该文以国家级贫困县W县为例,结合光伏扶贫信息化建设,系统梳理近年来4种典型的光伏扶贫模式,对比分析各种模式的适用范围及其特点,设计光伏扶贫综合效益计算方法。运用层次分析法和模糊综合评价法设计基于光伏扶贫指标评价的收益分配方法,根据典型案例分析,验证所提方法的有效性。综合从5个视角5个层面构建光伏扶贫效益提升机制总体架构,旨在为中国贫困地区光伏扶贫工程提供技术与决策支撑。     

稻田春玉米氮、磷、钾配方施肥数学模型的初步研究

采用氮、磷、钾三因素旋转组合设计,通过计算机模拟寻优,建立了稻田春玉米--杂交晚稻种植制度中玉米产量--施肥量,玉米生产利润--施肥量数学模型:分析了氮(X₁)、磷(X₂)、钾(X₃)的主效应及交互效应与产量的关系,它们对产量的影响为氮＞钾＞磷.筛选出玉米产量≥8250kg/hm²的最优方案为:N394.96～401.25kg/hm²、P₂O₅116.99～121.8kg/hm²、K₂O 232.29～237.06kg/hm²,其比例为N∶P₂O₅K₂O=3.4∶1∶2.并筛选出玉米利润≥6800元/hm²的最优方案为:N380.60～385.55kg/hm²,P₂O₅104.73～108.03kg/hm²、K₂O222.20～225.12kg/hm².其比例为N∶P₂O₅K₂O=3.6∶1∶2.1。     

云南松优势木胸径生长模型研究

以云南省金沙江流域永仁县的云南松天然次生林优势木胸径为研究对象,选择Logistics、Gompertz、Richards、Korf、Levakovic、严格苏马克和Hossfld模型对其进行拟合.通过对总相对误差、平均相对误差、平均相对误差绝对值和预估精度的分析,从中选出最优生长模型.研究结果显示,这些生长模型对云南松天然次生林优势木胸径生长拟合的精度基本相近.最优生长模型为Gompertz模型.     

阻尼喷头动能分布试验及模型

针对阻尼喷头外流场水力学特性研究较少的问题,该文研究了单位体积动能、动能强度与有无散水齿、不同喷嘴直径之间的关系。在工作压力分别为175、200、250和300 k Pa,喷嘴直径分别为3.6、4.0、4.4和4.8 mm下,采用激光雨滴谱仪对Nelson R33阻尼喷头的水滴直径、速度和数目等参数进行试验测试,并对试验结果分析及模型建立。结果表明:有无散水齿条件下的单位体积动能均有逐渐增大的趋势;距喷头相同测点处,单位体积动能随喷嘴直径的增大而减小;给出了有无散水齿下不同喷嘴阻尼喷头单位体积水滴动能分布模型,相关系数均在0.94以上;在距喷头0~4 m,不同喷嘴直径的动能强度较小且差值不超过0.002 W/m2,在距喷头较远处,不同喷嘴直径的动能强度差值较大,最大差值达到0.006 W/m2。有散水齿时,动能强度在不同压力下波动均比较小,差值不超过5%。该结果为进一步研究阻尼喷头外流场水力学特性提供理论依据。     

基于隐马尔科夫模型的深度视频哺乳母猪高危动作识别

哺乳母猪的高危动作和仔猪存活率有密切关系,能直接体现其母性行为能力,而这些高危动作又与其姿态转换的频率、持续时间等密切相关。针对猪舍环境下,环境光线变化、母猪与仔猪黏连、猪体形变等给哺乳母猪姿态转换识别带来的困难。该文以梅花母猪为研究对象,以Kinect2.0采集的深度视频图像为数据源,提出基于Faster R-CNN和隐马尔科夫模型的哺乳母猪姿态转换识别算法,通过FasterR-CNN产生候选区域,并采用维特比算法构建定位管道;利用Otsu分割和形态学处理提取疑似转换片段中母猪躯干部、尾部和身体上下两侧的高度序列,由隐马尔科夫模型识别姿态转换。结果表明,对姿态转换片段识别的精度为93.67%、召回率为87.84%。研究结果可为全天候母猪行为自动识别提供技术参考。     

轻小型喷灌机组技术评价主成分模型及应用

为解决轻小型喷灌机组喷洒运行、效果检测和能耗分析中涉及到的技术指标综合评价问题,提出采用主成分分析法对喷灌机组进行综合评价的数学模型。总结了喷灌机组喷灌面积、喷灌强度、组合均匀度和能耗等多种单技术评价指标,增加了综合评价的过程。选取评价其技术特性的5个单重要指标,应用所建的评价模型对4套喷灌机组进行综合评价。结果表明：前2个主成分包含了5个指标全部信息的98.75%,最终利用综合主成分公式得到4套喷灌机组综合技术评价指标的排名。该模型可对喷灌机组技术指标进行综合评价,也可为喷灌机组的设计优劣提供评判依据。     

Knot attributes and occlusion of naturally pruned branches of Fagus sylvatica

The aim of this study was to develop models on occluded branch characteristics for Fagus sylvatica (beech) based on 41 sample trees. A total of 717 beech branches were sampled; this information was then used to predict (1) the time for a complete occlusion, (2) the total radius of the occluded branch inside the trunk, (3) the branch insertion angle at the year of its death and during branch development, and (4) the dead branch portion of the occluded branch (loose knot). Generalized hierarchical mixed models with nonlinear forms were used in this analysis. The models explained between 6.3 and 52.2% of the total variance (including random effects 23.8–77.1%). The diameter of the occluded branch and the stem radial increment played dominant roles as predictors. Larger branches showed a significantly longer occlusion time, a larger occluded branch radius, a steeper insertion angle, and a higher loose knot portion. Simulations showed a biologically reasonable overall behavior of the models. The residual variation was tolerable for integrating the models into a growth simulation system.     

间伐强度对不同林分类型美景度的影响

以南京无想寺国家森林公园5个典型林分为对象,分析了不同间伐强度间美景度的差异,建立了美景度与景观要素的关系模型。结果表明:间伐尤其是强度间伐能大幅提高各林分美景度;林分密度、胸径、郁闭度等是影响该地区林内景观质量的主要因子;较好的通透性、较大的平均胸径及树高有利于提高林分美景度,而林分密度和郁闭度增大会给景观美学质量带来负面影响,进行生态风景林构建时应注意协调抚育措施对各林分因子的影响。     

台州柑橘黄龙病防控研究新进展

根据十几年对柑橘木虱和柑橘黄龙病发生规律与防控技术研究探讨,明确了柑橘木虱在台州橘林的发生分布规律和抽样技术,分析了柑橘木虱虫株率和带毒率与黄龙病、黄龙病与柑橘产量损失等之间的关系,探讨了柑橘黄龙病预警和柑橘木虱防治指标,建立了不同管理方式下的疫情扩散模型预测橘林经济寿命,提出了柑橘黄龙病综合防控技术和可防可控的理念。     

A user-centric approach for information modelling in arable farming

Agriculture and farmers face a great challenge in effectively manage information both internally and externally in order to improve the economic and operational efficiency of operations, reduce environmental impact and comply with various documentation requirements. As a part of meeting this challenge, the flow of information between decisions processes defined as realizing a decision must be analyzed and modelled as a prerequisite for the subsequent design, construction and implementation of information systems.This paper defines the actors, their role and communication specifics associated with the various decision and control processes in farmers’ information management. Core-task analysis and core task demands from earlier research are utilised as premises for the modelling of information flow from the farmers’ point of view. A user-friendly generic FMIS design reference model is the primary objective for the study in which planning, execution and evaluation measures have been incorporated.A user-centric approach to model the information flows for targeted field operations is presented. The information models are centred around the farmer as the principal decision maker and involves external entities as well as mobile unit entities as the main information producers. This is a detailed approach to information modelling that will enable the generation of a Farm Management Information System in crop production.