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1.
The IEC61850 standard and the existing bus protection data model are limited in the definition of data-model about dead-zone protection and charge protection for bus-tie. The paper analyzes the dead-zone protection and charge protection for bus-tie,and the data of input,output and setting based on the latest issued technical specifications intelligent substation. The data models of dead-zone protection and charge protection of bus-tie are developed for PCS915 bus protection. It improves the logic node modeling of bus protection and can provide useful information for the protection data-model configuration of intelligent substations.  相似文献   

2.
The paper mainly analyzes and studies mode of bus communication based on optical fiber at one_point to multiple_point and mode of point_to_point communication based on wireless at one_point to multiple_point. The advantages and disadvantages of two communication modes are given. Considering the demands on FA data communication,the paper presents transmitting data based on network mode and connection mode,implementing application protocol based on object oriented mode and international standard. Considering the requirements of FTU unit for data communication, the paper proposes the network inner operating system in FTU unit, which is indispensable. Data are transmitted on client/server mode, defined and organized on object oriented mode and transmitted on logical address.  相似文献   

3.
The main means of the voltage-reactive power control of substation are adjusting the taps of load-tap-changing transformer or the reasonable capacity of parallel compensating capacitors according to the operation condition of substation.The "nine-area control strategy" is widely used to adjust voltage in the stated range and reduce the transmission capability of reactive power for power system at present.By analyzing the existent shortages of nine-area control mode for voltage-reactive power,an adjusting voltage calculation method is put forward,input data of which are the real time data of current,voltage and power of the substation.Then operation decision of voltage-reactive power control method of substation is made.By the simulating analysis,predigesting method of upper system is built,based on which an applied real time calculating model and calculating steps is given.  相似文献   

4.
A design scheme using IEEE1394 serial interface to achieve communication between PC computer and DSP controller is introduced, which is used in real-time imitating for car-engine integrated controlling system. First, the rule of high speed IEEE1394 serial communication using TSB41BA3/TSB12LV01B interface is discussed. Further, the design scheme of software and hardware of communication sub-system is probed. The application effect is good in the car-engine integrated controlling system developed.  相似文献   

5.
At first, this paper introduces the EFB. Then it introduces the EFB manufacturers and three airlines’ applications of EFB. To make the content simple and clear, the paper presents a contrast table on EFB’s hardware and software. According to the comparative of analysis, the Analytic Hierarchy Process and Excel’s calculation, the paper gets weight coefficient as a theory of EFB design.  相似文献   

6.
As a standardized formal language, the SDL has widely been used in the software development. In order to extend its application field, it has been explored to use in hardware design.This paper gives a logical gate circuit-and gate as an example to explain the method of applying SDL to describe and simulate/validate the hardware characters by the SDT tool. The various logic circuits or digital circuits may be made to the SDL packages because the SDL supports the object oriented technology. These packages can be directly invoked in the design of the complex digital system, so it is possible to describe and simulate/validate the complex digital system.The experiment has proved that the application of SDL for hardware design is feasible and rather convenient.  相似文献   

7.
数据挖掘技术在农业信息网站中的应用研究   总被引:1,自引:0,他引:1  
为了在农业网站的海量数据中获取有用信息,运用数据挖掘技术对网站数据进行特征分析,并选择合适的数据抽取算法对网站数据进行抽取,然后根据此模式对农业网站的数据进行了定量、定性分析,从而建立了合适的数据抽取模型。能够为其他的应用提供帮助和服务,并能用于其他的知识应用体系中。  相似文献   

8.
为了研究黄土丘陵沟壑区缓坡地土地利用与水土流失的作用机理,选取中科院安塞水土保持综合试验站9个缓坡试验小区为研究对象,分析了2009—2011年不同土地利用配置方式(谷子地、柳枝稷地、撂荒地、2/3谷子-1/3柳枝稷地、2/3谷子-1/3撂荒地)的侵蚀产沙特征及其与降雨、植被覆盖度的关系以及减沙效益。结果表明:缓坡不同土地利用配置方式的次降雨产沙量大小为谷子地>2/3谷子-1/3柳枝稷地>2/3谷子-1/3撂荒地>柳枝稷地>撂荒地,与短历时高强度降雨关系密切;7月可能是泥沙量产生的敏感时期;短历时高强度暴雨往往是年产沙量变化的主要原因;与谷子地相比,柳枝稷地、撂荒地、2/3谷子-1/3柳枝稷地、2/3谷子-1/3撂荒地均表现出不同程度的减沙效应,减沙效应大小为:撂荒地>柳枝稷地>2/3谷子-1/3撂荒地>2/3谷子-1/3柳枝稷地;植被覆盖度的提高能有效地减少产沙量。研究结果可以为缓坡土地利用对水土流失的影响评价提供一定的参考依据。  相似文献   

9.
WEPP模型中的CLIGEN与BPCDG应用对比研究   总被引:9,自引:0,他引:9  
通过对遂宁组紫色土产流、产沙侵蚀的观测,运用迄今为止最为复杂的土壤侵蚀预测模型WEPP模型进行单次降雨侵蚀预测,与实测值比较,并对比通过气候生成器CLIGEN和断点生成器BPCDG的产生的气候参数对预测值的影响。通过分析比较结果,认为WEPP模型对遂宁组紫色土侵蚀过程预测合理,而且利用断点生成器BPCDG的预测结果要优于气候生成器CLIGEN的预测结果。  相似文献   

10.
《保鲜与加工》1998,(2):89-93
A traditional method of experiment on demarcating thermocouple is analyzed and its shortcoming is indicated.It is proposed that the experimental device for demarcating thermocouple should be advanced through application of a microcomputer.The timing for data sampling is carried out in a real time clock way and then the analogue signal is converted into digital information through a A/D converter.Finally, the results of demarcating thermocouple are audio-visually displayed on the screen in a graphic mode.  相似文献   

11.
It is a very important task that using a liquid crystal display module to replace the computer monitor and realizing the dynamic display of wave and data without dithering. The paper describes the way to process sampling data using synchronous technology, to transform data and to find unknowable coordinate. The transforming of address and the drawing of wave and the scrolling of wave are introduced. The dots link up with each other and the wave has no dithering. The dynamic wave and static parameter can coexist. The engineering application shows that the method is effective and economical.  相似文献   

12.
以陆地棉中棉所16为研究材料,采用植物形态学、解剖学方法及栽培技术对海南冬季棉花多年出现的"双重子房"棉铃进行初步研究.结果表明:双重子房棉铃花蕾的形态由共同的苞叶、花萼、花冠、雄蕊、柱头、花柱及生长在大子房中的小子房所组成;小子房早在棉花开花前已经形成,并与大子房争夺营养物质,导致落铃、烂铃;"双重子房"棉铃的生长发...  相似文献   

13.
我国预制菜产品标准体系建设存在政府部门参与度低、产品种类繁多、产品成分复杂、标准制定有局限性、产品标准缺失、标准化人才匮乏、与国际标准接轨不足等问题,预制菜标准体系空白亟需完善和填补。综述了我国预制菜标准体系的研究现状及研究进展,并基于工标网、食品伙伴网、广东省农业标准化协会发布的标准统计数据,分析了目前所面临的问题并提出了对策建议,以期为我国预制菜标准化体系建设提供参考依据。  相似文献   

14.
G. Backes    G. Schwarz    G. Wenzel  A. Jahoor 《Plant Breeding》1996,115(5):419-421
A quantitative trait loci (QTL) analysis of quantitative powdery mildew resistance was performed on 216 doubled haploid lines derived from a cross between the winter-barley varieties ‘Igri’ and ‘Danilo’ using 67 RFLP loci. Resistance to powdery mildew was determined in the field with natural infection and on detached primary leaves with a specific isolate. The major QTL found in both sets of analysis mapped to the same chromosomal region. No further QTL could be found in the analysis based on detached leaves and one additional minor QTL was found in the analysis based on field data.  相似文献   

15.
GIS技术在人工影响天气作业气象探测资料分析中的应用   总被引:2,自引:2,他引:0  
笔者以焦作市人工影响天气作业指挥系统为实例,分析了气象探测资料在人工影响天气作业指挥中的综合处理应用,介绍了组件式GIS技术在人影作业指挥系统中应用的总体思路,并阐述了该系统中GIS应用的主要方面,包括离散点探测资料的分析处理、雷达资料处理显示、各类探测资料的融合叠加、精细化预报产品的图形化显示及火箭安全射击范围管理、区域协作区管理等。实现了人工影响天气作业指挥中气象探测数据、预报预警信息、火箭射击区域等数据的空间管理,基于GIS可以对作业效果进行科学评估。  相似文献   

16.
基于R语言的GGE双标图在玉米品种区域试验中的应用   总被引:1,自引:3,他引:1  
为了鉴定高产稳产玉米新品种以及为玉米高产栽培提供理论依据,通过基于R语言的GGE双标图法分析了10个玉米新组合在四川省甘孜州高海拔地区生态条件下的丰产、稳产性和适应性,同时分析了5个试验点对参试组合的辨别力和代表性。结果表明:‘康玉试0903’和CH327 2个组合高产且稳产;而SZ694较高产,但稳产性稍差,在海螺沟试验点有特殊适应性。综合各试验点的区分力和代表性,丹巴、九龙和海螺沟较好:九龙和海螺沟的区分能力强,丹巴试验点的代表性最佳。  相似文献   

17.
近年来,我国坚果行业市场规模快速增长,产值近万亿。统计了坚果行业国家标准、行业标准、团体标准的内容、数量及标龄等,对国内坚果行业标准现状进行分析。在此基础上,找出坚果行业在标准化工作方面存在的问题并提出针对性建议,旨在通过标准化这一手段保证我国坚果食品质量安全,并推动产业高质量发展。  相似文献   

18.
How to remove the background , to eliminate the misdetection caused by vehicle changes road or it covers the detection window of the road detected partly, is a big problem to be handled in vehicle detection system.This paper presents an improved frame-difference method based on Video,and describes how to detect and count vehicles in detecting zone dynamically.With this method, we can count the vehicles passing by accurately, collect the traffic flow of each roadway reliably.We provide real-time traffic parameters for the ITS.  相似文献   

19.
气候变化对沈阳地区大田作物的影响   总被引:3,自引:6,他引:3  
为了当地农业结构调整、保障粮食生产提供依据,研究沈阳地区1951-2010年气候变化,采用气候倾向率及标准偏差方法对气候变化做定量分析。结果表明:沈阳地区年平均气温倾向率为0.196℃/10a,气候跃变之后年平均气温升高0.7℃;年降水量倾向率为-16.724 mm/10a,气候跃变之后降水减少40mm,多雨年在减少,少雨年在增加;第一场透雨出现时间被推迟,个别年份播种期受到限制。气候跃变之后终霜日提前,初霜日后推,延长了无霜期,作物播种期可适当早播;降水量减少、第一场透雨出现时间后延和不稳定,对作物生长和播种影响较大,成为农作物正常生长和产量稳定提高的限制因素。  相似文献   

20.
The paper analyzed the effect of disturbances that occur during transmission in the fiber and the influence of the selectivity of coupling implement on the fiber on the basic of experiment and theory.  相似文献   

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