喷雾高度可调的果园风送喷雾机的设计

【目的】设计喷雾高度可调的牵引式果园风送喷雾机,以满足不同果树对喷雾机喷雾高度可调的要求。【方法】针对轴流风机式果园风送喷雾机难以满足不同果树喷雾高度可变的不足,基于喷雾高度可调的目的,设计了一种由1对转向相反的离心风机和角度可调的导流风箱为核心的牵引式果园风送喷雾机,在需求分析和虚拟三维建模的基础上,完成了各关键部件技术参数和整机结构的确定,并通过试验分析了该喷雾机在不同喷雾角度、风机转速、喷雾距离和喷雾压力条件下喷雾沉积量的分布情况。【结果】设计的以转向相反的离心风机和角度可调的导流风箱为核心的牵引式果园风送喷雾机,在离心风机转速为1 200r/min、喷雾距离为2.5m、喷雾压力为0.7MPa、导流风箱的角度为0°和15°时,喷雾沉积量适宜的施药高度分别为0.8~2.4m和1.6~3.2m。【结论】所设计的果园风送喷雾机可以满足果园对不同高度果树施药的农艺要求。     

果园多风机风送喷雾机聚风筒聚风特性的试验研究

针对传统果园多风机风送喷雾机存在风能利用率低,出风口到靶标之间喷雾四散飘移的问题,对风机配置聚风筒（直筒式、渐缩式、渐开式）的风送喷雾系统的聚风喷雾性能进行研究。通过对聚风筒风场进行仿真模拟,设计对标试验确定了仿真模型与计算的可靠性。设计单因素试验和响应面参数优化试验分析风筒类型、聚风筒长度和风机转速对聚风特性的影响并确定聚风筒的最佳参数设计组合。试验结果表明：有聚风筒的风送喷雾系统对雾滴的胁迫作用明显显著优于无风筒的,且呈现了较好的聚风雾化作用,渐缩式风筒的性能尤为明显;气流集中性能由高到低排序为渐缩式、直筒式、渐开式、无风筒,聚风筒胁迫雾滴的横向穿透性能由高到低为渐缩式、直筒式、渐开式;风筒长度在30～70cm范围内,长度越长,聚风性能越好;随着转速呈倍数的增加,风场速度峰值也呈倍数增加,转速的改变不影响速度峰值的位置。聚风筒最佳参数设计组合为风筒类型为渐缩式,风筒长度为70cm,风机转速1 440r/min,此组合下的风速为4.156m/s,风场纵向幅宽为1 585.32mm。     

Support system for efficient dosage of orchard and vineyard spraying products

This paper establishes a system to support the dose evaluation part of the pesticide registration process so that growers can make more efficient use of different spraying products across a broad range of European orchards and vineyards. The system comprises: a dose adjustment model and a small database of standard target structures (i.e., regional exemplars where efficient and efficacious use of pesticide is obtained at the label dose rate). The model includes a generalised scaling group relationship between the parameters that describe: sprayer output, target row structure and spray volume deposit. The upper limit for dose adjustment is based on the environmental fate of pesticide and this is represented in the model by the ratio of maximum ground area dose rate to minimum efficacious deposit which is normalised for alignment with target structure measurements. The model is used to examine the leaf-wall-area dose rate recently proposed by the European agrochemical manufacturing industry for harmonising pesticide registration. Good agreement is demonstrated between published measurements and model predictions of ground area and leaf-wall-area dose rate variation at constant deposit for a wide range of target structures (i.e., English pome- and stone-fruit orchards and Italian vineyards). The results are used to establish standard target structures for spraying products with different uses. These standards are needed by regulators to: translate between the different methods of expressing dose rate and improve the accuracy of label dose recommendations. The standards are also needed by growers to enable: more accurate calibration of spraying equipment and prediction of the optimum adjustment of label dose rate for different orchards and vineyards.     

Y型棚架式果园的3WZ-300风送喷雾机设计与试验

目的 针对Y型棚架式果树的需风特性设计一款风送喷雾机,探究机具对此树形的施药规律,为新式果园栽植工艺的植保机具设计提供参考。方法 结合棚架梨树Y型树冠需风特性,设计一款异形导风管,确定发散型射流口,喷雾范围可全面覆盖冠层,并进行整机配置,风机使用无级调速带轮进行调速。以作业速度、出口风速、出风口与冠层中部高度差作为试验参数,以靶标雾滴覆盖率、靶标雾滴沉积量以及地面雾滴沉积量作为评价指标,设计田间试验。利用Design-Expert软件建立响应曲面分析参数对指标的影响,并对机具作业参数进行优化。结果 优化结果表明：3WZ-300风送喷雾机在作业速度0.8 m/s、出口风速22 m/s、出风口中部与梨树冠层中部高度差为5.1 cm时,靶标雾滴覆盖率为39.79%,靶标雾滴沉积量为9.89 μL/cm²,地面雾滴沉积量为5.41 μL/cm²,有效附着药液占比60.1%。结论 该喷雾机满足果园作业要求,施药效果较好,为棚架式果园喷雾机的设计及机具参数优化提供了参考。     

A new integrated CFD modelling approach towards air-assisted orchard spraying—Part II: Validation for different sprayer types

A computational fluid dynamics (CFD) model to simulate airflow from air-assisted orchard sprayers through pear canopies was validated for three different sprayers; single-fan (Condor V), two-fan (Duoprop) and four-fan sprayers (AirJet Quatt). The first two sprayers are widely used in Belgium and the latter one is a new design. Validation experiments were carried out in an experimental orchard (pcfruit, Velm, Belgium) in spring 2008. Ultrasonic anemometers were used to measure the time-averaged velocity components at different vertical positions before the tree and after the tree when the sprayers were driven through the orchard. The model was able to predict accurately the peak jet velocity, U_m from all the sprayers considered at all distances from the sprayer centre and vertical positions. More than 95% of the local relative errors of U_m were below 20%. Average relative errors, E, and root mean square errors, E_RMS, were all less than 11.04% and 1.68 m s⁻¹, respectively. The regions of high- (up to 18.0 m s⁻¹ upstream) and low (down to 2.8 m s⁻¹ downstream)-air velocity zones for all the sprayers were accurately predicted. The simulation results showed that the Condor V sprayer had a highly disturbed vertical jet velocity profile, especially at higher heights. The Duoprop sprayer had high jet velocities at the two-fan positions and lower jet velocity in between the two fans. Within the canopy height the AirJet Quatt sprayer showed a more uniform distribution of air than the other two sprayers except the minor peaks at the fan positions. These situations were all confirmed by the measurements.     

高地隙植保机速度自动控制系统研制

针对当前高地隙植保机自动化程度不高、作业时行驶速度变化较大影响施药质量等问题,设计具备手动、自动切换功能的速度自动控制系统。以雷沃ARBOS高地隙植保机为研究平台,采用机电一体化控制方法对其变速执行机构、速度控制过程与特性进行分析,采用基于比例微分算法的速度控制方法,实时计算并控制速度执行机构的动作,实现行驶速度的自动调节。田间试验表明,高地隙植保机速度自动控制系统能够按照速度指令控制静液压行走驱动系统的输出,在平均行驶速度为0.21、0.83和0.94 m/s时,最大速度控制误差分别为0.05、0.10和0.10 m/s,满足高地隙植保机行驶速度控制的基本要求。     

Energy generation for an ad hoc wireless sensor network-based monitoring system using animal head movement

The supply of energy to electronics is an imperative constraining factor to be considered during the design process of mobile ad hoc wireless sensor networks (MANETs). This influence is especially important when the MANET is deployed unattended or the wireless modules within the MANET are not easily accessible. Therefore, exploring novel sources of energy generation rather than operating electronics only on limited power supplies such as batteries is a major challenge. Monitoring free-ranging animal behavior is an application in which the entities (animals) within the MANET are not readily accessible; however, animal movement can be potentially used to generate energy. In this study, the head movements of individual sheep in a flock during grazing were monitored in order to investigate the amount of energy that can be generated by these movements. By applying the Lagrange-d’Alembert Principle to this problem, the equations of motion from each neck-mounted sensor as well as the amount of mechanical energy generated per time instant (each second) during upward and downward head movements were calculated. This resulted in the production of 857 mW and 1660 mW during the downward and upward movements, respectively. Furthermore, the energy consumption of each wireless node within the MANET was estimated to be 117.8 mW per second. Conversion of energy from mechanical to electrical requires miniature electromechanical generators that can currently provide between 25% and 50% conversion efficiency. Even using the worst conversion efficiency (25%), a minimum of 214 ± 25 mW of electrical energy per second could be generated. This amount exceeds the energy consumed by the wireless sensors that can be used to gather parameters describing animal behavior such as neck and head movement. This study suggests that the amount of energy generated by the vertical neck-head movement of sheep during grazing can be converted to useful electrical power adequate to provide power for operation of wireless sensor nodes on a continuous basis within a MANET-based animal behavior monitoring system.     

Spot-application of fungicide for wild blueberry using an automated prototype variable rate sprayer

Wild blueberry producers apply fungicide uniformly without considering significant bare spots in the field. The wrong or over use of fungicide in bare spots results in an increased cost of production and threatens the environment. An automated prototype variable rate (VR) sprayer was used for spot-application (SA) of Chlorothalonil (Bravo^®) fungicide in a wild blueberry field. Eighteen 6.1 m wide test tracks were selected in the field and bare spots were mapped using a real-time kinematics-global positioning system (RTK-GPS). Six plots were selected randomly for three different application rates. Water sensitive papers (WSP) were placed in foliage and bare spots in SA and uniform-application (UA) tracks. The percent area coverage (PAC) of WSP with both SA and UA in foliage and bare spot areas were calculated. Plant growth parameters were measured from all 108 randomly selected plots in SA, UA and control (CN) tracks for comparison. Plant images were taken over six selected plots in each of the 18 tracks. Images were analyzed using custom developed software to calculate the percentage of green pixels (PGP) for determining the effect of Bravo^® on plant health. Fruit yield parameters were also measured from selected plots for comparison. Non-significance of the t test for SA versus UA plant targets’ PAC indicated that there was no significant bias in the SA with saving (9.90–51.22 %) and SA was accurate. Bravo^® did not show any significant difference on plant growth parameters among SA, UA and CN. However, PGP, floral bud and harvestable yield of SA and UA were significantly increased over CN. Therefore, a VR sprayer could be used for SA of fungicides in wild blueberry cropping system to reduce chemical usage and maintain crop productivity.     

Virtual vineyard for grapevine management purposes: A RFID/GPS application

A method for combining data stored in an RFID microchip implanted inside grapevine plants and a GPS system is described. GIS software was used to register geographic coordinates of detected points, and to develop a specific database in which information useful for the positioning phase are stored. The final product is a digital map accessible via mobile or desktop systems that represents the “virtual vineyard”. In this digital representation, each grapevine plant marked by RFID can be selected, viewed and edited. Free-to-use software was implemented for use by consumers.     

芒果茶黄蓟马（Scirtothrips dorsalis Hood）田间发生动态及监测方法研究

[目的]探明茶黄蓟马在芒果园的田间发生规律,明确芒果树不同物候期茶黄蓟马最适合的监测方法,为芒果茶黄蓟马监测与防治提供科学依据.[方法]分别于2010和2012年的2月20日至当年11月30日,在广西亚热带作物研究所芒果品种园、芒果示范园对广西的两个主栽芒果品种金煌芒和桂热芒82号,从花期至小果期同时采用蓝板加诱剂法、蓝板法和弹击法,在果实膨大期至当年末次梢老熟采用蓝板加诱剂法,监测记录茶黄蓟马的发生动态,分析芒果树物候期、气象条件和品种对茶黄蓟马田间发生的影响.[结果]芒果盛花期至小果期、嫩梢期是茶黄蓟马发生高峰,随着花期结束、果实膨大与嫩梢老熟,田间虫口密度逐步下降.高温干燥天气适宜茶黄蓟马发生及繁育,其对芒果树品种不具有选择性.3种监测方法间的回归方程分别为：y=1.717x＋14.321（y：蓝板加诱剂法,x：弹击法,R2=0.777,P＜0.05）、y=1.256x＋0.288（y：蓝板加诱剂法,x：蓝板法,R2=0.979,P＜0.05）和y=1.375x＋11.080（y：蓝板法,x：弹击法,R2=0.801,P＜0.05）.[结论]茶黄蓟马的田间发生动态与芒果树的物候期、气象条件密切相关,与芒果品种无关.弹击法、蓝板法和蓝板加诱剂法均与芒果茶黄蓟马的监测结果相关,但从可操作性方面考虑,在芒果初花期至小果期宜采用弹击法,在其他物候期宜采用蓝板加诱剂法.     

果园灌溉物联网实时监控系统的研制与试验

目的 简化果园网络部署,延伸信号覆盖范围,提供精细、实时的灌溉监控,并提高其对传统设备的兼容性。方法 通过窄带物联网(NB-IoT)和LoRa混合组网实现远程数据传输、延伸基站信号覆盖范围。采用终端电学参数检测电路及标定功率,结合异常检测算法,精准监测设备运行状态,并将异常状态即时上传,降低数据上传频率。同时在保证处理能力的前提下降低处理器主频,从而延长待机时长。结果 果园现场监测系统实现了150 ms内上报异常状态,并将上报次数限制为每年2万次。校正检测功率后,功率的线性回归预测决定系数(R²)为0.999 8。通过宏生成JSON数据,生成时长为cJSON方法的10%,进一步降低MCU计算需求。在满足计算和控制需求的前提下,2 MHz的微处理器主频和200 mA·H锂电池可以满足果园灌溉监控系统计算和持续工作的最低要求,采用低功耗微处理器可以进一步延长工作时间。结论 监控系统延伸了NB-IoT网络的覆盖范围,可实现精准、低成本和实时的远程监控。     

山地果园电动单轨运输机控制装置的设计

【目的】研制一种山地果园电动单轨运输机的控制装置,以提高单轨运输机的智能性和安全性,实现其自动控制。【方法】基于单片机、直流电动机、无线通信模块等设计蓄电池驱动的山地果园单轨运输机的控制装置,通过模拟山地果园地形,分别对控制装置的行驶速度调节、制动性能及系统功耗进行测试。【结果】电动山地果园单轨运输机的控制装置由单片机、供电单元、直流电动机、直流电动机驱动模块、制动模块、行驶速度调节模块、无线通信模块、手动控制按键及限位停车模块组成。模拟测试结果表明:单轨运输机的行驶速度可实现0.1~0.6m/s内的加减速调节控制;单轨运输机的行驶速度随着装载质量的增加而逐渐变小;当单轨运输机在39°坡下坡行驶时,通过测速电路控制电磁式失电制动器,能有效解决单轨运输机行驶速度超出安全速度的问题。经连续1个月的实际测试,限位停车控制模块能够实现单轨运输机的及时停车,其可靠性达100%,手动按键及无线遥控均能实现单轨运输机的有效控制,无线遥控最大可靠距离为450m,控制装置响应时间约为2s。【结论】所设计的控制装置运行稳定可靠,能满足单轨运输机智能性、安全性和自制性的预期设计要求。     

果园机械化经济效益分析——以江苏烨佳梨园为例

针对果园机械化经济评价问题,采用成本分析理论模型和敏感性分析法,对江苏烨佳梨园生产过程中疏花、采摘、施药、除草、剪枝、施肥深松和灌溉7 个环节各作业方式的最低平均成本、机械装备替代传统作业的临界规模、机械装备相对传统作业方式的平均节省成本和临界规模的影响因素进行研究。结果表明:1)机械装备作业在一定规模后可以明显比传统方式作业节省成本,如手持式疏花器在种植面积大于0.11 hm²时,是更具经济效益的疏花方式,移动式水肥一体化系统在种植面积大于34.33 hm²时,是更具经济效益的灌溉方式;2)机械装备固定成本和传统作业方式零工成本是影响临界规模的重要因素,固定成本增加20%临界规模将增大约20%,零工成本增加20%临界规模将减小15%以上;3)案例中,梨园在机械装备平均成本最低的种植面积下,使用机械装备替代传统方式作业,全作业环节可节约成本11 536.87元/hm²。机械化装备需要果园规模大于临界规模才具有经济效益,随着固定成本降低,零工工资上升,机械装备作业替代传统方式作业临界规模变小,果园机械装备经济适用范围增大。     

The use of mobile devices with multi-tag technologies for an overall contextualized vineyard management

This paper describes a Viticulture Service-Oriented Framework (VSOF) which turns around context elements or tags that are placed in the field and which can be decoded by mobile devices such as mobile phones or PDAs. The tags are used to automatically associate a field location to the relevant database tables or records and also to access contextual information or services. By pointing a mobile device to a tag, the viticulturalist may download data such as climatic data or upload information such as disease and pest incidence in a simple way, without having to provide coordinates or any other references, and without having to return to a central office. This work is part of an effort to implement a large-scale distributed cooperative network in the Douro Demarcated Region in Northeast Portugal, a region in which the effort makes particular sense due to the extremely variable topography and mesoclimates. The possibility of exchanging contextualized information and accessing contextualized services in the field, using well-known devices such as cell phones, may contribute to increase the rate of adoption of information technology in viticulture, and contribute to more efficient and closer-to-the-crops practices.     

Economic analysis for smart sprayer application in wild blueberry fields

The wild blueberry industry is spending over $80 million CAD per year on agrochemicals for 93 000 ha under production in North America. A pressing need to reduce agro-chemical usage and production cost has resulted in the development of a smart sprayer for spot-application of agrochemicals in wild blueberry fields. This paper encompasses the economic analysis to determine the potential savings for spot-applications of agrochemicals using a smart sprayer. The economic analysis compared the smart sprayer with two other commercially available sprayers (basic and swath control). The swath control sprayer and smart sprayer both featured GPS auto-steer and boom section control to reduce over-spray in already applied areas based on GPS position. The basic sprayer used a foam marker for guidance with no swath control management. The smart sprayer featured a machine vision system that automatically detected target areas in the field further reducing agrochemical input by shutting individual nozzles off in non-target areas in the field. The cost analysis was performed to compare the different features of the sprayer technologies, i.e., base sprayer, additional technology, training, usage, repair and maintenance. The additional components installed on the smart sprayer were justified in terms of agrochemicals/water savings via spot-applications, tractor fuel and operator’s time. The application total cost was $2052 ha^?1 using the basic sprayer, $1799 ha^?1 using the swath control sprayer, and $1138 ha^?1 using the smart sprayer over a 2 year production cycle of the selected fields that were used in this study. The payback period ranged from 2.0 years (60 ha field size) to 9.8 years (20 ha field size) using the swath control sprayer. The payback period ranged from 11 months (60 ha field size) to 3.5 years (20 ha field size) when using the smart sprayer. Results revealed that the smart sprayer had significant advantage from both an environmental and economic perspective over the other two sprayers.     

基于ZigBee和3G/4G技术的分布式果园远程环境监控系统的设计

在现有温室智能监控系统的基础上,结合ZigBee技术、3G/4G通信技术、嵌入式监控主机技术,设计了一套分布式果园远程环境监控系统.基于单片机CC2530设计了一体化传感器采集节点和物联网网关,并阐述了其硬件和软件的设计原理.结果表明:远程管理中心配置的嵌入式监控主机可分布式管理果园群站点,实现远距离数据传输、分析、存储等功能;在安装调试过程中,该系统性能稳定、能耗低、功能较全面,并在数据的采集与传输以及整体管理方面达到了预定的设计要求.     

Soil spatial variability and site-specific fertilization maps in an apple orchard

In the present study, the spatial variability of some soil physical and chemical properties in a 0.8 ha apple orchard were studied. Sixty soil samples were taken from two sampling depths: 0–0.3 m and 0.3–0.6 m. The soil samples were analyzed for the following soil properties: soil texture, pH, cation exchange capacity and NO₃–N, NH₄–N, P, K, Na, Ca, Mg, Fe, Zn, Mn, Cu, B and organic matter content. Data analysis indicated that most of the nutrients were at sufficient levels. The site-specific application map for N was created based on the amount of N that was removed from the soil with the yield of the previous year. By applying N site-specifically, 38% of N could be saved compared to uniform application.     

雨滴撞击植物叶片的运动过程监测装置的研制北大核心CSCD

植物对降雨动能的耗散削减是其重要的水土保持机制,然而缺乏相应的观测测量装置,使得对叶片动能的耗散过程认识并不清楚。为了研究植物叶片在雨滴撞击后的运动过程以及叶片运动能量的变化,以聚偏氟乙烯(PVDF)压电薄膜传感器为基础,研制有效检测雨滴撞击之后叶片的运动以及能量耗散测定的装置,对女贞叶片在雨滴击打下的振动进行测量并验证该装置可行性。在对雨滴撞击叶片过程仔细分析研究的基础上,进行监测装置的模块化自主设计,整个监测装置由雨滴发生、叶片运动的监测捕捉和信号的收集处理三个模块组成,其中雨滴发生模块可根据实际情况进行取舍(也可直接测定天然降雨)。薄膜传感系统输出的电压信号包含了雨滴撞击,小水滴飞溅以及薄水层扩散等方面信息。系统输出的电压是背景的几倍到几十倍,电压上峰值和雨滴动能存在明显的线性关系(R^(2)=0.959),信号频域分析发现该系统也能有效捕获连续雨滴撞击树叶的振动信号特征。对于不同动能的雨滴,重复之间的变异系数为<10%的弱变异和10%~100%的中等变异,说明整个装置具有良好的系统稳定性。女贞叶片耗散的能量与雨滴输入能量之间具有明显函数关系,叶片所耗散的动能仅占初始雨滴动能的3%~5%,这可能与没有监测以叶柄扭动、振动的过程有关。该装置可监测雨滴撞击叶片所引起的运动情况和叶片对雨滴动能的耗散特征,有利于深入认识植物对降雨动能耗散的机制。     

解非对称线性方程组的一种方法

本文研究了求解非对称线性方程组的广义Hessenberg方法 (GHM) 的截断格式——不完全广义Hessenberg方法(IGH)。该方法是在迭代过程的每一步,采用不完全正交化方法,使产生的第m+1个向量1+mv只与前面的已经求得的p个向量(1+-pmv,…,mv)正交,从而达到了节约存储量和运算量的目的。本文同时给出了有关IGH方法的一些性质。