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FF总线现场设备的开发 总被引:2,自引:0,他引:2
介绍了适合不同层次开发者的,基金会现场总线(FF)产品开发的不同方式及开发环节,提供了一套实用的产品开发工具并举例说明如何利用其开发基金地现场总线的现场设备。 相似文献
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本书详细地描述了当前总线控制系统在不同领域的应用,以基金会现场总线、LonWorks现场总线、Profibus现场总线、CAN现场总线、DeviceNet现场总线、HART现场总线、Modbus现场总线、ASi现场总线规范介绍为基础.对全球主要控制系统制造公司现场总线产品的技术特点、功能指标和应用范围做了介绍.系统地描述了现场总线控制系统的设计过程、开发步骤和不同规范现场总线的应用,给出了现场总线控制系统在不同工业和民用工程领域的应用实例。 相似文献
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基金会现场总线技术及其产品开发 总被引:2,自引:1,他引:1
本文对基金会现场总线(FF总线)的背景和功能进行了介绍,分析了FF现场总线的技术特点,并对基于基金会现场总线产品的开发思路与步骤进行了讨论。 相似文献
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现场总线是目前自动控制技术发展的趋势,基金会现场总线(Foundation Fieldbus)在众多现场总线中脱颖而出,成为技术上最先进的现场总路线。基于基金会现场总线标准的用户层协议的实现有助于开发面向仪器、仪表等控制设备的应用,促进我国自控技术的数字化、智能化进程。本文从协议及软件的角度分析了用户层协议,给出了基金会现场总线用户层协议的设计模型及实现方法。 相似文献
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1 绪论 现场总线的定义是:“从控制室联结到现场设备的双向全数字通信总线”。基金会现场总线(FF)是针对过程工业重要实时控制应用而设计的一种现场总线。它借用了国际标准化组织(ISO)的开放系统互联(OSI)的模型,但另外增加了“用户层”。而功能块则是用户层的主要内容。用户直接使用功能块构筑自己的控制系统,所以现场总线基金会(FF)一再强调它不仅仅是信号标准(数字的4~20mA),也不仅仅是通信标准,而是一个系统标准。这是FF和许多其他类型现场总线的主要区别之一。现场总线基金会制定了一套标准的功能块。也允许制造商自行开发特有… 相似文献
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现场总线与智能现场仪表设计技术 总被引:4,自引:0,他引:4
现场总线作为用于工业现场的局域网,其运行基础是智能现场总线仪表。本文根据基金会现场总线的基本,探讨了智能现场总线仪表的设计方法。 相似文献
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Given a planar graph $G=(V,E)$ and a rooted forest ${\FF}=(V_{\FF}, A_{\FF})$
with leaf set $V$, we wish to decide whether $G$ has a plane embedding $\GG$
satisfying the following condition: There are $|V_{\FF}|-|V|$ pairwise noncrossing
Jordan curves in the plane one-to-one corresponding to the nonleaf vertices of
${\FF}$ such that for every nonleaf vertex $f$ of ${\FF}$, the interior of the curve
$\JJ_f$ corresponding to $f$ contains all the leaf descendants of $f$ in ${\FF}$
but contains no other leaves of ${\FF}$.
This problem arises from theoretical studies in geographic database systems.
It is unknown whether this problem can be solved in polynomial time.
This paper presents an almost linear-time algorithm for a nontrivial special case
where the set of leaf descendants of each nonleaf vertex $f$ in ${\FF}$ induces
a connected subgraph of $G$. 相似文献
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Tina A. Greenlee Gavin Horn Denise L. Smith George Fahey Eric Goldstein 《Ergonomics》2014,57(5):764-773
This study examined the following: effects of simulated firefighting (FF) activities under heat stress on sustained attention; whether incident rehabilitation (IR) influences performance; and relationships between performance, affect and personality. Firefighters performed ~18 min of FF. Attention, physiological, perceptual and psychological assessments were made before and after FF, IR and recovery. IR had no effects. Self-rated Energy increased, Tiredness decreased and Anxiety increased immediately post-FF; all returned to baseline 120 min post. The immediate effect of FF was faster reaction time (RT) followed by slowing after recovery. Perceived Energy at baseline was associated (p-values < 0.05) with faster and Tiredness with slower post-FF RTs; Accuracy was unaffected. Conscientiousness was negatively associated with RT before and 120 min following FF. RTs were faster following FF, accuracy was unchanged. Higher baseline Energy/lower Tiredness were associated with faster, less variable RTs at baseline and post-FF. Those with higher Conscientiousness had faster RTs. Research should further investigate higher-level cognitive processing following, or ideally during, FF. 相似文献
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根据智能阀门定位器总线化的要求,开发了基于FF协议的通信接口,阐述了双处理器结构的OEM开发思想.给出了实现FF通信的详细步骤和开发工具。经测试,阀门定位器实现了FF总线通信功能.证明了开发方案的可行性。 相似文献
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Valentina Orsini 《Asian journal of control》2023,25(3):1715-1730
This paper deals with Feedback/Feedforward (FB/FF) control of a gantry crane system intended for the transport of payloads that take values over a known interval. It is also assumed that the crane is affected by unmeasurable disturbances. A new 2DoF control architecture is proposed whose purpose is to speed up the horizontal payload transition while minimizing its oscillations. The main features of the control design procedure are as follows: (1) The output FB controller is designed to ensure robust closed loop stability and steady-state exact payload positioning; (2) the disturbance is estimated by means of an observer, and its transient effect is compensated through the FF action; and (3) the robust FF control action is given by the optimally weighted sum of the two contributions due to FF Plant Inversion (FFPI) and FF Closed Loop Inversion (FFCLI) control schemes. 相似文献