首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
电子秤精度比较高,但只能解决称量系统静态误差,若把电子秤与PLC结合,用PLC控制给料设备的启停和给料速度,即可控制系统的动态精度,达到精确称量的目的.利用此原理,使用S7-300,设计了LF炉铁合金微调称量控制系统.该系统配置包括电子秤和PLC,其电子秤由称重传感器和称重变送器组成,通过PLC的输出控制变频器的频率以实现精确加料,用WinCC完成界面设计,以S7-300通信模块CP544与连铸机DCS系统Net90通讯,在上位机VAX上进行数据处理.  相似文献   

2.
摘要:介绍了打包机称自动称重系统的改进设计,有效地解决了原打包机电子秤自动称重系统中存在的成品包重称重问题。提出了该自动称重系统的改造方案,增加小型可编程控制器和触摸屏的使用实现原有功能,优化了打包机自动称重系统,提高了纤维生产线自动化控制水平。  相似文献   

3.
刘飞  郭欣 《科技资讯》2013,(14):64-64
称重精度是煤炭快速定量装车系统中的重要参数,目前称重系统称重仪表显示结果多为求和称结果,不能直观反应每个传感器的应力变化,当误差较大时很难分析装车站结构或调试问题。本文研究了基于现场工业总线的称重信号同步采样系统,对每个传感器的采样,通过软硬件滤波将结果记录下来。这有助于分析称重系统误差原因,改善安装工艺,提高称重精度。  相似文献   

4.
阐述了模拟称重传感器信号发生器的设计,此信号发生器的应用对电子秤检定维修工作具有重要意义.  相似文献   

5.
该文文旨在利用磁悬浮技术,实现对轻量物件的较高精度称重,并通过对原理及应用做了详尽的阐述和实验,设计了一个吸式的磁悬浮式电子秤。该文涵盖磁悬浮电秤系统的设计方案,电磁线圈非线性、系统的电磁力模型、系统的控制模型及控制电路的设计与调试。解决了磁悬浮电子秤设计的几个难点:电磁场的非线性问题、各种材料和部件的选取和机械加工及控制电路的设计与参数调试。该文的创新点有:(1)采用红外收发二极管设计系统的距离传感器,同时也使用摄像头作为传感装置进行试验;(2)创新图像化反馈,采用NI模块配合LabVIEW进行图像化处理;(3)自行绕制电磁线圈,采用最佳1j-50软磁镍铁合金作为铁芯。  相似文献   

6.
在设计电子秤称重监控系统的过程中,基于组态王与VB对动态数据交换技术的支持,利用VB的MSComm通信控件解决电子秤与计算机的串行通信,实现对配料称重过程实时监控。通过现场实施,该系统降低了误差,提高了工作效率和企业的管理水平。  相似文献   

7.
本文对影响电子秤计量精度的两个关键部分,传感器部分和放大转换部分进行了分析,提出了克服由这两部分所引起的电子秤计量误差的方法,说明了数据处理的计算机程序实现。  相似文献   

8.
本文分析了影响混凝土搅拌楼称重传感器测量精度的内在和外在因素,讨论了提高称重传感器测量精度可靠性的五大措施,从而保证了混凝土搅拌楼自动配料计量准确可靠,对生产出高品质的混凝土具有实际应用价值。  相似文献   

9.
根据电子秤的工作原理及电子秤的总体设计及特点,设计了电子秤的组成。电子秤是一种装备了电子元件的秤重计量设备,具有秤量快、读数方便,能在恶劣环境条件下工作、便于与计算机技术相结合而实现称重技术和过程控制的自动化等特点。  相似文献   

10.
为保持电子秤的精度,提出一种针对使用电阻式应变传感器的电子秤校准方法.使用C8051F350单片机和HAC-up系列无线模块实现数据传输与数据处理,用AD8555芯片代替放大电路,且在不烧断AD8555多晶硅熔丝的情况下实现校准,整个系统集成度高且安装简单.实验表明,整个系统校准后可恢复为初始精度.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号