农产品色选技术的发展分析

随着人民生活水平的提高,人们对食品质量越来越重视,要求对大米、茶叶、杂粮及水果等进行分级分类。该文综述了国内外色选技术及设备的发展现状,并介绍了几种色选设备应用情况。最后提出针对天津的特色农产品品质分级采用色选技术及设备的研究。     

番茄色选机分选系统延迟时间计算

番茄色选分选机是一种利用光电技术分析识别物料的品质优劣,并利用压缩空气将不符合要求物料剔除的设备.该设备采用独特而有效的筛选方式,可有效提高物料的品质等级,并针对色选系统对物料从CCD传感器镜头前下落到气枪喷嘴前的延迟时间进行设计与计算.     

红外技术在农业色选领域的应用

介绍了红外技术在农业色选领域的应用，以马铃薯品质检测为主要分析对象，概述了检测原理、检测过程和分析结果，为进一步将红外技术应用到青贮饲料、牧草和甜菜等其他农产品物料的检测提供依据。      

色选技术在粮食和农产品领域的应用和发展趋势

色选机是由喂料机构、溜板(带式)、传感器、喷阀和电脑控制系统构成的光电一体化设备,根据被选物料本身的光学特征差异,利用光电原理从被选物料中选出异色颗粒。当不合格颗粒与合格颗粒的大小、密度十分接近时,可以说色选是唯一可选择的非人工分拣方式。色选技术可以把颗粒度相近农产品中的霉变、黄变和杂质等对人体有害的异色粒有效剔除。     

基于Matlab对成熟番茄RGB阈值的确定

对成熟番茄进行识别是提高番茄深加工品质的保证,也是番茄收获机械中色选部分的核心。为此,如何准确地确定物料RGB三原色的阈值是非常重要的。Matlab是一款著名的数学处理软件,拥有大量的图像处理及输出函数,可以通过程序控制来快速确定指定物料RGB阈值的最佳范围,从而进行成熟番茄的图像识别。与传统编程方法相比,这种方法具有更为简单方便和包含信息量全面等优点。     

脱绒棉种色选机双CCD检测系统设计与仿真分析

设计了一种脱绒棉种双侧双CCD(Charge coupled device)色选检测系统。通过对该检测系统的光学子系统、图像采集子系统和处理子系统等的分析与设计,结合仿真分析和测试试验,验证了系统效果。其中,图像采集子系统采用彩色线阵CCD对脱绒棉种进行成熟度信息采集、黑白线阵CCD对棉种进行完整度信息采集;图像处理和分析用于提取关键特征信息做棉种类型的判别分析。试验结果表明,检测系统设计的光学子系统模块能够得到特征清晰的图像,处理子系统能满足双图像采集子系统CCD正常采集物料特征信息,系统能够保证分选的实时性和稳定性要求。     

农产品滚筒式均质干燥装置的设计与试验研究

针对物料在干燥过程中无法在线测量水分、物料加热不均匀等问题,设计了一种由PLC控制的新型在线测水物料干燥装置,并分别介绍了烘干机的工作原理和PLC控制系统。对干燥装置进行性能试验,结果表明：装置能保证物料水分达到安全储藏范围,解决了干燥装置对物料加热不均匀的问题,能够准确实现温湿度和质量的在线检测,提高了干燥装置的智能化水平,对提升烘干效率及谷物品质具有重大意义。     

如何正确使用比重式种子清选机

正压式比重种子清选机是种子加工过程中的一台主要设备 ,是专门用以分选具有不同质量的较小尺寸颗粒并淘汰轻废物的重力式分选机。在任何情况下 ,当物料经适当的设备进行初清及尺寸分级后 ,比重选操作会得到最好的效果。1　比重选工作原理位于比重选工作台上的物料在下面风力的作用下处于悬浮状态 ,其中 ,上层为比重较小物料 ,下层为比重较大物料 ,中层为混合区 ,物料层化后在工作台的振动作用下开始分离 ,与台面接触的比重较大物料向台面高边方向移动 ,与此同时 ,比重较小的物料由于位于台面上的上层 ,不与振动的台面接触 ,悬浮着向台面低…     

基于影响锤片式粉碎机性能主要因素的分析与研究

锤片式粉碎机是农牧业机械的主要产品之一,其性能的优劣直接影响到物料的产量、质量及企业的经济效益。为此,分析了影响锤片式粉碎机生产率、度电产量、物料粒度等性能方面的诸多因素,并对粉碎室内物料流场及物料在筛片上的受力情况进行了较为详细的分析、研究。该结果为今后改进锤片式粉碎机的性能提供了理论及实验基础。     

农业物料静载力学性能的研究现状及趋势

随着农业工程学科的发展,深入研究农业物料的力学性能显得越来越重要,这是因为农业物料的这一性能既可以为农业和农产品加工装备的发明和改进提供理论依据,也可以在农产品品质检测和品种改良方面提供理论支持。为此,介绍了农业物料静载力学性能的国内外研究现状,并对其发展趋势进行了分析。     

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。