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1.
2ZT—2型甜菜移栽机栽植系统的参数分析   总被引:12,自引:1,他引:12  
对2ZT-2型甜菜移栽机栽植器进行了运动分析与仿真研究.应用ADAMS建立了移栽机栽植器的模型,通过运动学分析对2ZT-2型甜菜移栽机的相关设计参数进行了优化,得出了影响因素变化时对纸筒苗栽植状态的影响规律,并得出了该甜菜移栽机栽植器合理的特征参数值和鸭嘴开启运动规律.  相似文献   

2.
栽植器是自走式移栽机的核心部件,其性能决定了烟苗落地时的直立度以及烟苗入土深度。比较国内现有几种类型栽植器的优缺点后,设计出一种新型的侧置四连杆旋转鸭嘴式烟苗栽植器,并进行样机田间试验,栽植效果较好。  相似文献   

3.
移栽机自动分钵式栽植器机构分析与运动仿真   总被引:6,自引:0,他引:6  
提出了一种移栽机自动分钵式栽植器,并对分钵原理、栽植器的机构以及钵苗运动轨迹进行了分析与仿真.结果表明,栽植器两机械手配合准确、运行稳定,可实现自动连续分钵.田间试验测得,栽植角度为88.08°~88.34°,其变异系数为2.37%~2.92%;栽植株距为350.67~351.17mm,其变异系数为1.42%~1.60%.结果表明该栽植器运行稳定,不受前进速度的影响.  相似文献   

4.
对棉花移栽机栽植器进行了理论分析、虚拟样机分析和物理样机试验分析。根据棉花移栽的特殊需要设计了分土靴式栽植器,减少了移栽过程的钵苗损伤,并保证了立苗率。通过分土靴式栽植器三维造型,建立了分土靴式栽植器的虚拟样机。在该栽植器的虚拟样机试验中确定了弹片的弹性系数、弹片的作用点以及机组行进速度的最优值,并通过物理样机得到了验证。  相似文献   

5.
针对各类移栽机存在的移栽速率低、直立度低、加工精度要求高等问题,设计了一种蔬菜移栽机五杆栽植机构,由五连杆机构、鸭嘴栽植器、链轮传动机构及鸭嘴开合机构等部分组成。根据零速投苗的原理要求,通过Solid Works建模软件建立了五杆栽植机构虚拟样机模型,通过模型简化和格式转换导入ADAMS中进行运动学仿真,得出其运动轨迹以及速度位移曲线,验证了结构选择和参数设计的合理性。根据设计参数制作了样机,进行了田间试验,结果表明:株距误差率仅为2. 93%,秧苗与地面的夹角α均大于70°,满足栽植要求。  相似文献   

6.
吊篮式移栽机栽植器的研究   总被引:3,自引:0,他引:3  
随着我国经济作物生产规模的迅速扩大,广大农区迫切需要移栽机械。吊篮式移栽机以其独特的优点在国内外得到了广泛的应用。目前,国内对吊篮式移栽机的研究尚不够深入,基本参数之间的关系和设计计算仍然是一个需要解决的关键问题。为此,初步进行了吊篮式移栽机栽植器的运动参数的研究,由吊篮式移栽机的运动轨迹建立了栽植器的运动方程,推导出特征系数λ的值;根据特征参数λ≥1是栽植器正常工作的必要条件这一经典理论,确立了移栽机在栽植过程中的技术要求和结构参数,建立了它们之间的内在联系,满足了移栽机的农艺要求。  相似文献   

7.
为了更好地推广应用蔬菜移栽机,设计研发了一种2ZB-2型蔬菜移栽机,其行距、株距、移栽深度、前进速度、移栽速度等参数可由电气系统控制并可实现无极调整。同时,使用移栽机进行了田间试验,结果表明:各项试验指标均能符合《JB/T 10291-2013旱地栽植机械》作业规范要求。  相似文献   

8.
烟苗栽植器是烟草移栽机的核心机构,该机栽植器设计应用偏置双圆盘四连杆旋转工作原理,适合于栽植钵苗和漂浮苗。分析烟苗移栽时的运动情况知特征系数λ>1是栽植器设计及保证移栽质量的基本依据和正常工作的必要条件,同时通过在不同栽植速度和深度情况下的正交试验确定了栽植器各设计参数的具体值,从而建立鸭嘴运动轨迹的数学模型。  相似文献   

9.
针对甘蓝传统手工移栽劳动强度大、效率低的问题,根据甘蓝种植农艺要求,研制了适宜甘蓝裸苗移栽的2ZS-3型挠性圆盘式甘蓝补水移栽机。分析了幼苗栽植过程中的运动轨迹,选取了适宜栽苗区间。对送苗装置、挠性圆盘装置、开沟器和覆土镇压装置等关键部件进行了设计,确定了设计参数,最后经田间试验,各项指标符合标准要求。   相似文献   

10.
吊杯式移栽机栽植株距调节的研究   总被引:1,自引:0,他引:1  
对栽植株距、传动比、吊杯数量以及移栽机前进速度与栽植圆盘线速度之间的关系进行了分析,设计了2 ZB-2型吊杯式移栽机的传动系统,用6种链轮与吊杯的组合来调节株距。田间试验结果表明,该吊杯式移栽机工作稳定可靠,栽植株距稳定一致,3~4吊杯的株距变异系数为0.48~0.88。研究结果可为今后吊杯式移栽机的研制和计算提供参考。  相似文献   

11.
Overland water and salt flows in a set of rice paddies   总被引:1,自引:0,他引:1  
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.  相似文献   

12.
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。  相似文献   

13.
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。  相似文献   

14.
对《种子法》存在问题的探讨   总被引:1,自引:0,他引:1  
《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。  相似文献   

15.
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.  相似文献   

16.
赵异 《湖南农机》2007,(3):31-32
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。  相似文献   

17.
A European irrigation map for spatially distributed agricultural modelling   总被引:1,自引:0,他引:1  
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.  相似文献   

18.
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。  相似文献   

19.
农村信息化服务的现状及建设措施   总被引:2,自引:0,他引:2  
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。  相似文献   

20.
车辆ABS控制算法的研究及探讨   总被引:1,自引:0,他引:1  
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。  相似文献   

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