分置式耕播联合作业机连接机构的研究

用补偿式三点悬挂装置作为分置式耕播联合作业机的中间连接机构,保证了播种机传动地轮与地面的紧密接触,传动可靠。用解析式及图解法的静力学分析说明了连接机构设计的正确性。     

悬挂式深松机耕深监控装置开发与试验

针对深松作业时用户无法有效监控耕地深度的问题,以悬挂式深松机耕深为检测对象,研究了一种基于三点悬挂装置下拉杆与水平方向夹角和车身侧倾角的耕深监控装置。对深松机组悬挂结构进行分析,建立了深松机水平及侧倾作业时耕深计算模型,以下拉杆与水平方向夹角和车身侧倾角的变化间接确定耕深;设计了耕深监控装置,装置内置MPU6050模块可实时得到角度变化并反馈耕深值。为验证装置的性能,进行了田间试验,结果显示,耕深最大误差不超过1.1 cm,表明该悬挂式深松机耕深监控装置精度高、稳定性好,符合设计要求。     

履带式林下耕播机平顺性分析

为了验证履带式林下耕播机在运输过程中的稳定性和可靠性,对履带式林下耕播机进行平顺性分析。使用RecurDyn软件建立虚拟样机,编写相应的路面文件。首先,进行普通工况下林下耕播机以不同速度通过H级道路时的平顺性的仿真分析。其次,进行林下耕播机通过矩形障碍物时的仿真分析。最后,进行了林下耕播机能够通过的最大侧倾路面分析。结果表明,林下耕播机在H级道路上行驶,速度在6 km/h以下为合理速度,在通过矩形障碍物时尽量以一侧履带接地,另一侧通过障碍物时较为稳定;通过150 mm高障碍物时,应以2 km/h或者4 km/h速度通过;林下耕播机通过不侧翻的极限侧倾角度为41°。通过对林下耕播机的仿真分析,证明履带式林下耕播机在林间道路行驶符合要求,对于林下耕播机的使用和后续优化有着重要的指导意义。     

悬挂式旋耕机耕深监测系统设计与试验

针对旋耕机作业耕深测量效率低和缺乏有效在线监测手段的问题,以悬挂式旋耕机耕深为检测对象,研究了一种基于旋耕机悬挂姿态的非线性耕深监测系统,以提高旋耕作业质量自动化监测水平。首先,对旋耕机的悬挂姿态进行分析,确定了旋耕机耕深与悬挂姿态之间的数学关系式,综合考虑悬挂式旋耕机组的结构形变和车轮下陷等因素对测量结果的影响,建立了三参数非线性耕深测量模型,该模型通过拟合旋耕机悬挂姿态角和耕深的关系,可实时计算实际耕作状态下的耕深;其次,为验证该模型的测量精度,设计了适用于车载终端的悬挂式旋耕机耕深监测系统,该系统集成卫星定位、实时耕深测量、作业速度测量、作业面积计算、稳定性评估等模块,支持数据云端存储与共享;最后,对模型参数进行标定试验,采用最小二乘法对模型进行参数优化,利用标定后的耕深监测系统开展多组田间试验。与人工测量结果对比显示,耕深最大误差不超过0. 80 cm,均方根误差不超过0. 55 cm,表明该悬挂式旋耕机耕深监测系统精度高、稳定性好。通过耕深质量评估试验生成多组带有位置信息的评估报表,表明该监测系统能够对旋耕耕深质量进行全面评估。     

秸秆粉碎还田与整地复式作业机连接装置设计与试验

针对东北稻区秸秆粉碎质量不达标影响后续整地质量,机具下地作业次数多土壤压实严重的问题,设计一种连接装置可连接秸秆粉碎还田机与整地机具,一次下地实现秸秆粉碎还田与整地的复式作业。综合考虑秸秆粉碎还田与犁耕之间的交互作用与匹配性,从横垂面、纵垂面、水平面3个运动平面对连接装置进行理论分析,并通过仿真对连接装置进行稳定性分析。通过理论分析,进行连接装置横垂面幅宽匹配性、纵垂面作业位置匹配性、水平面动力学匹配性研究;根据理论分析得的连接参数,进行连接装置结构设计;通过ANSYS Workbench进行关键连接装置的静力学分析及动态分析,设计的装置满足强度要求及运输状态的稳定性要求。复式作业与分段作业的田间试验表明,复式作业能够达到犁耕的工作稳定性要求,耕深平均值为17.3 cm,耕深稳定性系数为91.2%,耕宽平均值为119.2 cm,耕宽稳定性系数为93.6%;复式作业植被覆盖率为95.7%,分段作业植被覆盖率为98.3%,二者无显著性差异,且复式作业油耗比分段作业少,可减少油耗3.15 kg/hm²。     

悬挂式深松机耕整地耕深检测方法研究

耕深作为深松作业质量的重要指标,长期以来无法实现在线评估,目前以人工抽测为主,误差大,效率低。以提高农机深松耕整地作业质量为目标,提出一种基于深松机组姿态估测的耕深检测方法及系统。首先分析了牵引拖拉机以及悬挂式深松机在作业过程中的运动轨迹,建立了拖拉机与深松机作业耕深检测模型。该模型通过检测安装在拖拉机后悬挂杆和悬挂式深松机上的姿态传感器输出角度,实时计算深松机耕深。为验证该检测模型的精度,设计了基于嵌入式ARM内核的耕深检测传感器和深松作业检测系统,该系统集卫星定位系统(GPS)、移动网络传输(GPRS)、数据存储(SD卡)等于一体,能实时采集深松机作业耕深、作业位置、作业速度及航向信息,数据存储在检测系统的终端设备中,并通过移动网络传送至远程数据中心做进一步融合处理,以对深松作业质量进行综合评价。将耕深检测传感器进行静态标定,耕深检测标定误差小于0.88 cm,平均误差小于0.21 cm,均方根误差小于0.66 cm。利用标定后的传感器及深松作业检测系统在田间开展多组试验,试验结果显示该系统耕深检测最大误差为1.18 cm,多组试验数据的平均误差小于0.45 cm,均方根误差小于0.64 cm,表明该系统耕深检测精度和稳定性较高。     

双轴旋耕压槽播种开沟匀覆土作业机设计与试验*

针对目前小麦播种机械存在的播种质量差、播深稳定性差、复式作业程度低等问题,设计一种双轴旋耕压槽播种开沟匀覆土作业机,分析机具的工作原理,并根据实际作业需要,设计一种传动系统,计算出整机传动效率为0.716。为稳定开出5 cm宽,1~3 cm深的小麦种槽,设计一种特型的开槽轮,保证播种深度,提高播深与播宽稳定性;根据作业幅宽3 500 mm以及播种深度1~3 cm,确定绞龙长度与直径的参数,设计一种开沟匀覆土装置,采用左右两段绞龙机构,提高耕幅范围内的土壤平整度,并同样分左右两段绞龙机构,设计一种清土装置。田间对比试验表明样机的准确度为88.67%、离散度为45.45%、均匀度为73.74%,普通播种机的准确度为78.72%、离散度为39.38%、均匀度为44.83%。     

立旋式驱动型联合整地机的设计与试验

针对新疆常规联合整地机对黏重土壤播前整地作业耙深稳定性差、碎土率低及地表平整度低等问题,在结合新疆农业对播前整地作业要求、土壤特性等因素的基础上,设计了一种立旋式驱动型联合整地机,并完成整机的加工试制.通过对关键零部件的设计及理论分析,确定了传动系统、平土杠和钉齿镇压辊等零部件的结构参数,并通过运动分析确定耙齿转速为4...     

拖拉机液压悬挂耕深电液控制系统设计与试验

从拖拉机液压悬挂耕深电液控制系统原理出发,设计了一种以电液比例阀为主控制阀的耕深电液控制系统,建立该系统数学模型,分析其位控制和力控制特性,并进行了试验验证.试验结果表明:采用耕深电液控制系统,其位控制过渡时间为0.65 s,静差为±1.5 cm;力控制调节时间为7.5 s;力位综合控制耕深为20cm时,耕深的波动范围为±1 crn.能够满足农机具田间作业时耕深的控制精度和稳定性要求.     

三种新机具

三种新机具孙德元由辽宁省农机化研究所研制的ＩＣＧＬ－２４０型碎茬旋耕起拢机、５ＸＪ－３０型介电式种子清选机和２ＢＧ－６型带状耕播机近日通过了辽宁省科委、省农机局组织的专家鉴定。鉴定委员会认为这三项科研成果均达到国内领先水平。其中２ＢＧ－６带状耕播机获...     

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。