马铃薯播种机排种机械化种植技术研究

马铃薯是我国一种重要经济作物,在我国有较大的种植规模。为实现马铃薯种植的机械化,基于传感器和单片机技术,结合现有的马铃薯播种机,设计了一种新的排种系统,以解决马铃薯播种过程中的漏播和重播问题。该排种系统由操作显示屏、速度感应装置、数据分析模块、挡板控制器和报警装置几个部分组成。工作时,通过速度感应装置获取播种机的行进速度,然后由数据分析模块根据所设定的播种株距计算挡板开关的频率并进行控制,以达到精准播种的效果。对装载该排种系统的马铃薯播种机在4种不同行进速度工作时,进行薯种漏播率、直播率和株距数据调查,发现漏播率和重播率都很低,远远小于行业标准,且种植的株距与设定值差异很小,具有较高的精确性,能够很好地满足马铃薯种植的要求;其行进速度在0.8m/s左右时,种植质量和作业效率同时达到最佳。     

马铃薯智能排种机补种系统设计与试验

为提高马铃薯智能排种机的排种效率,降低作业人员的劳动强度,进一步提高马铃薯出芽及收获产量,对智能排种机的补种系统进行了设计。在智能排种机结构组成及工作原理基础上,建立马铃薯运动学参数模型,并加装补种装置,主要包括声光传感器、步进电机及报警装置等。给定合理的补种控制程序,进行试验,结果表明:设计的智能排种机补种系统补种合格率达97.5%以上,漏种指数试验平均值为1.1%,重种指数试验平均值为1.3%,各关键参数指标符合设计要求。该优化试验可为马铃薯智能排种机其他关键装置性能提升提供参考。     

基于卡尔曼滤波PID控制的精量排种器优化设计与试验

针对设施蔬菜种植过程存在漏播、重播问题,设计基于卡尔曼滤波PID控制技术的精量排种器。分别对排种器关键组件和监测装置进行结构设计,建立传感器实时监测车速信号的控制系统,同时以不同作物株距值共同作为控制依据,补偿融合卡尔曼滤波的PID控制方法,通过调控电机保持转速的稳定性,从而实现精量播种。仿真结果表明：卡尔曼滤波的引入,对噪声干扰起到良好抑制作用,可提高系统稳定性。以排种盘转速和行走速度为变量,以株距合格率、重播率、漏播率和株距变异系数为指标,进行两因素五水平的二次回归正交旋转组合试验。台架试验表明：在不同车速下,株距变异系数均在规定的≤35%指标范围内,排种盘转速为10 r/min,行走速度为1.6 km/h时,株距合格率为95.9%,重播率为2.9%,漏播率为1.9%,株距变异系数为12.1%,满足设施蔬菜的精量播种要求。     

玉米免耕播种机漏播补偿方法对比研究

为解决玉米免耕播种机播种作业时存在漏播的问题,针对漏播自补偿和漏播辅助补偿方法进行了对比研究。对水平圆盘排种器的排种性能进行试验,获取了排种器在不同排种盘转速和播种粒距下排种合格指数、漏播指数和重播指数。由漏播自补偿补种性能分析可得,在排种口检测漏播信号进行加速补种,补种的实际粒距LPR>1.5L,补种粒距依然为漏播,无法实现漏播补偿功能,若在种子脱离排种口之前检测到漏播信号,提前做好加速准备再进行补种,可实现漏播自补偿功能。由漏播自补偿试验可知,漏播自补偿受播种速度和播种粒距影响较大,在播种粒距为20、25cm,播种速度不大于5km/h时,补种合格率不小于88%,在播种粒距为15cm或播种速度大于5km/h时,补种合格率较低;由漏播辅助补偿补种性能试验可知,在播种速度3~7km/h,粒距15~25cm下,补种成功率不小于89%,在播种速度不大于5km/h,补种合格率不小于96%。为了保证补种位置精确,采用漏播辅助补偿装置进行补种,〖JP2〗需合理设计漏播补偿装置安装位置,同时受播种速度、播种粒距、排种盘线速度、投种角的影响,通过合理设计补种装置安装参数后,控制补种装置响应时间t和补偿装置排种盘的线速度vb实现补种位置的精确控制。     

马铃薯播种漏播检测自动补种装置设计与试验

针对勺式马铃薯播种机作业中排种勺空穴漏播需人工检测与补种的难题,提出了一种基于激光对射传感器的漏播检测方法,设计了一种马铃薯播种漏播检测自动补种装置,并验证了装置的漏播检测性能和自动补种性能.采用两对激光对射传感器和接触式行程开关传感器分别探测漏播空勺和准确补种位置,依靠步进电机驱动补种装置进行精确补种.试验结果表明:...     

甘蔗横向种植机补种系统设计与试验

针对甘蔗横向种植机在种植过程中出现的漏播问题,设计了一套基于51单片机的甘蔗实时补种系统。通过对充种、储种、供种、护种及投种过程进行运动学和动力学的仿真分析,确定了影响补种效果的主要因素,设计了补种系统的关键部件。该系统采用AT89C52单片机、3套对射型激光传感器分别对漏种、补种箱和储蔗槽中蔗种余量不足的情况进行信号采集,进行漏种计数显示和实现蔗种余量不足时的报警,步进电机作为动力源,驱动辊耙转动完成补种过程。选取行进速度和补种辊槽数为试验因素,以补种成功率和重置率为补种性能指标,进行了二因素五水平的正交旋转组合试验。结果表明,行进速度对补种成功率的影响极显著,补种辊槽数对补种成功率的影响极显著;利用Excel软件进行了二次回归方程分析,得出当行进速度为3 km/h、补种辊槽数为10个时,补种成功率达到93.97%,重置率为1.69%。设计的实时补种系统性能稳定可靠,解决了播种器工作过程中的漏种问题。     

免耕播种机漏播补偿系统设计与试验

针对免耕播种机作业时存在漏播问题,设计了一种漏播自动补偿系统,建立了补偿装置驱动的数学模型,应用滑模变结构控制算法设计了补偿系统控制器,并对补偿系统的动态响应性能进行了仿真分析。通过补种控制算法,确定了补种机构与主排种器的距离S和离地高度H,得到了补种排种盘转速n和播种机行进速度v_m、粒距L_l之间的关系曲线,对排种器安装高度H、粒距L_l、传送带速度v_m进行了二次回归正交试验,验证了漏播补偿系统的补种性能。台架试验的最佳工况组合为,补种排种器安装高度15.33 cm、粒距25.16 cm、传送带速度3.52 km/h时,补种成功率可达96.5%。田间试验表明,安装漏播补偿系统后,免耕播种机播种合格率均值为98.72%,有效提高了播种质量。     

具有自动补种功能的机械式精密排种系统

针对机械式精密排种器存在不同程度的漏排问题,设计了带有自动补种装置的精密排种器.利用光电传感器监测主排种器充种情况,当主排种器充种窝眼出现漏充种现象时,测控系统检测到信号并控制副排种器在恰当的时间排种,以确保补种位置准确.室内台架试验表明,补种成功率为91.01%～92.07%.总漏排种率降到0.6%～1.3%,所补排种子与其他种子之间粒距合格指数可达91.25%,实现了准确有效补种功能.     

玉米勺式排种器变速补种系统设计与试验

针对玉米勺式排种器出现的漏播问题,设计了一种变速补种系统,该系统采用光电传感器在偏离出种口20°位置进行提前检测,漏播发生时由步进电动机改变排种器转速越过空种槽达到实时补种的目的。为了使变速补种系统具有通用性,选取具有一定代表性的玉米籽粒外形形状品种:久龙5号(球形)、九单57(锥形)和郑单958(矩形),以不同转速作为试验因素,运用EDEM软件和排种器性能试验台进行排种性能研究。仿真结果表明:当转速不超过23.1 r/min时,排种性能受变速影响不超过2%,在转速达到27.7 r/min时,变速种子抖落现象明显;在转速达到32.3 r/min时,变速时种子会出现严重的抖落现象;试验结果表明:具有变速补种系统的勺式排种器转速处于13.9~23.1 r/min时,漏播率不超过1.4%,平均补种率达到89.95%,播种率达到98.7%。在转速为27.7 r/min时,比不具有变速补种系统的勺式排种器漏播指数降低10.4%,补种效果最为显著,在转速达到32.3 r/min时,补种效果不显著;3种玉米品种的排种性能优劣次序为:球形、矩形、锥形。     

巨菌草播种机漏播补种系统设计

针对缓坡地预切种式菌草种植机存在的漏播现象,提高菌草播种机械作业的质量和自动化水平,提出一种基于stm32的漏种补播系统,该系统采用光电对射传感器和编码器分别监测漏种和排种器转速,在监测到排种器漏种时驱动补种器步进电机执行补种动作,播种发生故障时自动报警。为验证系统的可靠性,对试验样机进行测试。结果表明,排种速度在1～6 km/h时,播种机的漏种率较低,漏种后的补种率高,提高了巨菌草种植机的播种质量。      

Overland water and salt flows in a set of rice paddies

Cultivation of paddy rice in semiarid areas of the world faces problems related to water scarcity. This paper aims at characterizing water use in a set of paddies located in the central Ebro basin of Spain using experimentation and computer simulation. A commercial field with six interconnected paddies, with a total area of 5.31 ha, was instrumented to measure discharge and water quality at the inflow and at the runoff outlet. The soil was classified as a Typic Calcixerept, and was characterized by a mild salinity (2.5 dS m⁻¹) and an infiltration rate of 5.8 mm day⁻¹. The evolution of flow depth at all paddies was recorded. Data from the 2002 rice-growing season was elaborated using a mass balance approach to estimate the infiltration rate and the evolution of discharge between paddies. Seasonal crop evapotranspiration, estimated with the surface renewal method, was 731 mm (5.1 mm day⁻¹), very similar to that of other summer cereals grown in the area, like corn. The irrigation input was 1874 mm, deep percolation was 830 mm and surface runoff was 372 mm. Irrigation efficiency was estimated as 41%. The quality of surface runoff water was slightly degraded due to evapoconcentration and to the contact with the soil. During the period 2001–2003, the electrical conductivity of surface runoff water was 54% higher than that of irrigation water. However, the runoff water was suitable for irrigation. A mechanistic mass balance model of inter-paddy water flow permitted to conclude that improvements in irrigation efficiency cannot be easily obtained in the experimental conditions. Since deep percolation losses more than double surface runoff losses, a reduction in irrigation discharge would not have much room for efficiency improvement. Simulations also showed that rice irrigation performance was not negatively affected by the fluctuating inflow hydrograph. These hydrographs are typical of turnouts located at the tail end of tertiary irrigation ditches. In fact, these are the sites where rice has been historically cultivated in the study area, since local soils are often saline-sodic and can only grow paddy rice taking advantage of the low salinity of the irrigation water. The low infiltration rate characteristic of these saline-sodic soils (an experimental value of 3.2 mm day⁻¹ was obtained) combined with a reduced irrigation discharge resulted in a simulated irrigation efficiency of 60%. Paddy rice irrigation efficiency can attain reasonable values in the local saline-sodic soils, where the infiltration rate is clearly smaller than the average daily rice evapotranspiration.     

瓦房店市水果生产标准化发展研究

瓦房店市是我国重要的水果生产基地,在国内水果生产领域占有重要地位。随着水果市场化的不断深入,如何满足和适应国内外市场需求成为瓦房店市水果生产的关键问题。从瓦房店市水果生产实际出发,阐述了实施水果生产标准化的必要性,提出了发展水果生产标准化的具体措施。     

金谷子耐旱TG118引种试种及推广应用

对引进的谷子新品种金谷子耐旱TG118进行品种比较试验和多点试种。结果表明：该品种抗旱、耐瘠、适应性强,稳产、高产、抗病抗风抗倒伏强,品质优良,粮草兼用,种植简单,省工易管;一般产量在6000kg/hm2以上,比当地主栽品种增产20%以上。最高产量达9450kg/hm2,适于在辽西北地区推广应用。     

对《种子法》存在问题的探讨

《种子法》是我国种植业第一部法律。自实施以来,为依法加强种子管理提供了有力的法律支撑,促进我国种子产业发生翻天覆地的变化。但随着依法管理工作的深入和种子产业的快速发展,《种子法》及配套规章的一些问题逐步显现出来。对《种子法》及配套规章存在的问题进行深入分析,对需要进一步补充的章节以及需要调整的内容进行深入探讨,以求更加完善和明确。     

Review of the Egyptian experience in implementing land drainage projects

About 30 years have passed since the Government of Egypt embarked on implementing a series of large scale drainage projects. At present, about 3.8 million acres have been provided with drainage systems on the basis of systematic pre-drainage investigations and designs. The target is to provide drains in approximately 6.4 million acres in the Nile Valley and Delta.The implementation of the subsurface drainage system is carried out by the public sector and private contractors under direct supervision of governmental regional departments. The implementation process depends on many factors related to the drainage material, machinery, manpower, site requirements, farmers and organizations involved. Problems and constraints are sometimes challenging, however, the annual rate of implementation has gradually increased to 170,000 acre/year.This paper discusses the different aspects involved in the implementation process of drainage systems. The development in materials, machinery and construction technologies will be reviewed. Institutional and management factors are going to be also considered.     

和谐社会理论建设的几点哲学思考

在新世纪,面对机遇和挑战,党的十六大把“社会更加和谐”作为全面建设更高水平的小康社会的一个重要目标。中国人素有社会和谐的理想;西方人自古也向往社会和谐;借鉴东西方两种和谐社会思想的经验、教训,构建社会主义和谐社会理论。     

A European irrigation map for spatially distributed agricultural modelling

We present a pan-European irrigation map based on regional European statistics, a European land use map and a global irrigation map. The map provides spatial information on the distribution of irrigated areas per crop type which allows determining irrigated areas at the level of spatial modelling units. The map is a requirement for a European scale assessment of the impacts of irrigated agriculture on water resources based on spatially distributed modelling of crop growth and water balance. The irrigation map was compiled in a two step procedure. First, irrigated areas were distributed to potentially irrigated crops at a regional level (European statistical regions NUTS3), combining Farm Structure Survey (FSS) data on irrigated area, crop-specific irrigated area for crops whenever available, and total crop area. Second, crop-specific irrigated area was distributed within each statistical region based on the crop distribution given in our land use map. A global map of irrigated areas with a 5′ resolution was used to further constrain the distribution within each NUTS3 based on the density of irrigated areas. The constrained distribution of irrigated areas as taken from statistics to a high resolution dataset enables us to estimate irrigated areas for various spatial entities, including administrative, natural and artificial units, providing a reasonable input scenario for large-scale distributed modelling applications. The dataset bridges a gap between global datasets and detailed regional data on the distribution of irrigated areas and provides information for various assessments and modelling applications.     

粉质仪和拉伸仪在面粉生产中的应用

在介绍粉质仪和拉伸仪结构和原理的基础上,探讨了粉质曲线中吸水率、形成时间、稳定时间、弱化度和评价值等指标与面粉品质的关系,以及如何根据拉伸曲线中面团最大拉伸阻力、延伸度和拉伸曲线面积等指标来评价面团品质,并结合生产实际,概述了粉质仪和拉伸仪在面粉生产中的作用。     

农村信息化服务的现状及建设措施

分析当前我国农村信息化服务的现状,提出加强农村信息化服务的新举措。     

车辆ABS控制算法的研究及探讨

对现代汽车的ABS控制算法作了一些简单的介绍,同时指出了它们的一些缺陷,相应地提出了几种对ABS的其它控制方法并加以探讨,其中着重论述了ABS门限值控制算法中参考车速的确定方法和基于附着系数的控制算法。