共查询到20条相似文献，搜索用时 718 毫秒
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"PC+运动控制器"型开放式数控系统 总被引：4，自引：0，他引：4
介绍了一种"PC 运动控制器"型开放式数控系统,分析了系统的硬件构成及其工作过程、系统软件组成模块以及上位机与下位机之间USB通讯的数据结构定义.最后从运动控制器发展角度分析了目前国内"PC 运动控制器"型开放式数控系统的发展情况. 相似文献
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电机智能监控保护系统中的通讯实现 总被引：1，自引：0，他引：1
在智能化电机监测保护系统中,常采用PC机作为上位机,多台单片机构成的智能监控保护器(以下称保护器)作为下位机,组成小型智能化通讯网络系统。其中作为下位机的单片机既可以独立进行各台电机的数据采集和现场控制,又可以和PC机之间相互传输数据;PC机可将数据进行处理、管理和存储,显示有关数据、曲线和波形,又可向各单片机发出控制命令,进行集中控制。为此,简要介绍了电机智能监控保护系统中通讯的实现方式,着重分析了系统中保护器内部的通讯以及保护器和PC机之间的通讯。 相似文献
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介绍了一项自主研发的智能节水温室系统,主要论述上位机的设计开发。上位机通过RS232串口发送控制指令到下位机中,采集下位机控制的现场传感器数据,并通过串口将数据送到上位机。上位机可以设定土壤的温、湿度等墒情指标的阈值,下位机根据上位机预置阈值来控制卷帘、通风和水泵等设备的相应操作,实现了精准灌溉、节水、节能。 相似文献
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针对北方水稻育秧大棚,设计了一套基于LabVIEW软件的水稻育秧大棚环境多点监控系统,实现了对育秧棚内温湿度等信息的实时采集,以及数据的存储、查看、分析、超限报警及控制等功能。系统采集模块以STC15W4K58S4单片机为核心,选用AM2302温湿度传感器采集各节点温湿度,B-LUX-V30B环境光传感器采集室外光照强度,数据通过无线串口模块建立无线传输网络实现数据的传输、汇总,上位机与下位机的数据传输运用RS232串口通信技术,并运用LabVIEW自身的Web远程网页发布功能达到用户远程监控的目的。最后,将系统在某育秧大棚内运行,并分析出育秧棚内温湿度分布特性。 相似文献
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根据厌氧发酵工艺流程,确定了厌氧发酵的主要控制参数,制定了基于PLC和力控组态软件的沼气工业化生产的自动控制系统设计方案.该控制系统采用PLC作为下位机,PC机和力控组态软件作为上位机,对采集的数据进行集中的管理和实时监控.在试验中,该自动控制系统表现出良好的稳定性和实用性,实现了沼气生产的自动控制. 相似文献
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Overland water and salt flows in a set of rice paddies 总被引：1，自引：0，他引：1
E. Playn O. Prez-Coveta A. Martínez-Cob J. Herrero P. García-Navarro B. Latorre P. Brufau J. Garcs 《Agricultural Water Management》2008,95(6):645-658
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
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车用发动机润滑油失效规律与更换周期研究 总被引：7，自引：0，他引：7
研究在正常使用条件下１０Ｗ／３０－ＱＣ级润滑油用于某型车用发动机时所表现的失效规律,确认期服从两参数Ｗｅｉｂｕｌｌ分布,并给出分布的尺度参数η和形状参数ｍ之最佳线性无偏估计（ＢＬＵＥ）同时,还为定量分析,计算车用发动机润滑油的使用可靠性和合理确定其更换周期提供了一套可供借鉴的方法,并给出了具体的计算实例。 相似文献
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赵国杰 《农业机械化与电气化》2011,(4):106-107
乡（镇）农技推广体系是农业发展的关键。介绍朝阳市农业技术推广体系的现状,针对目前体制及运行机制、服务手段等方面存在的问题,提出适合朝阳市乡（镇）农技推广体系改革与发展的对策,以期对全省农技推广体系改革和发展起到一些借鉴作用。 相似文献
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苑庆刚 《农业机械化与电气化》2010,(3):52-54
草莓果味酸甜爽口,营养价值高,为人们所喜爱的应市鲜果之一。由于草莓易受损伤和微生物侵染,因此其采收、贮藏过程极为重要。介绍草莓采收过程中的注意事项以及11种贮藏保鲜技术的实施步骤和操作方法,推介9种加工方式,为草莓产业化提供技术支持。 相似文献
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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
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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
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对《种子法》存在问题的探讨 总被引：1，自引：0，他引：1
李鹏 《农业机械化与电气化》2011,(6):129-130
《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
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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
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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