HMI

The process control functions and the operator interface, also referred to as man-machine interface (MMI) or human-machine interface (HMI), is provided by separate nodes. This approach is referred to as split-architecture, and it permits considerable flexibihty in choosing a configuration that most appropriately meets the needs of the application. 

FIG. 20-7 Effect of fineness on the flammability of metal powders. Hmi-mann, Nagy, and Brown, U.S. Bur. Mines Rep. Invest. 3722, 1943.)... 

The first set of case studies illustrates errors due to the inadequate design of the human-machine interface (HMI). The HMI is the boundary across which information is transmitted between the process and the plant worker. In the context of process control, the HMI may consist of analog displays such as chart records and dials, or modem video display unit (VDU) based control systems. Besides display elements, the HMI also includes controls such as buttons and switches, or devices such as trackballs in the case of computer controlled systems. The concept of the HMI can also be extended to include all means of conveying information to the worker, including the labeling of control equipment components and chemical containers. Further discussion regarding the HMI is provided in Chapter 2. This section contains examples of deficiencies in the display of process information, in various forms of labeling, and the use of inappropriate instrumentation scales. 

Design of the human-machine interface (HMI) such as control panels to ensure that process information can be readily accessed and interpreted and that appropriate control actions can be made... 

In an effort to form the dimer as the major product and to determine what effect the temperature of reaction had on the ratio of HMI to LMI, the hydroxybutenolide XVII was heated to reflux in benzene (bp = 80.1°C), toluene (bp = 110.6°C), and xylene (mixture bp = 137-144°C) in the presence of catalytic p-toluenesulfonic acid... 

Hansen, H., (1980) Reconstruction of the electron momentum distribution from a set of experimental Compton profiles, Hahn Meitner Institute (Berlin), Report HMI B 342. 

The wall heat flux qmi cannot be evaluated as in Section II,B. Numerous experimental studies on heat transfer in this two-phase forced-convection region have been carried out, and the results of these investigations are usually presented in the form of a correlation for the wall heat-transfer coefficient hmi, which is defined as in Eq. (32b). Most of these correlations fit one of two generalized forms. The first is... 

M. Meissner, S. Abens, P. Strelow Hahn-Meitner Institute Report, Berlin (2000) www.hmi.de/bensh/ sample-env/home.html... 

In the systems 1-4 HI was introduced into the reaction mixtures and formed the donor HMI very rapidly in No. 5 HMI was used ... 

The central computer is called the master terminal unit, or MTU. The MTU has two main functions to periodically obtain data from RTUs/PLCs and to control remote devices through the operator station. The operator interfaces with the MTU using software called human machine interface (HMI). The remote computer is called the program logic controller (PLC) or remote terminal unit (RTU). The RTU activates a relay (or switch) that turns mechanical equipment on and off. The RTU also collects data from sensors. Sensors perform measurement, and actuators perform control. 

Each of the independent controllers is linked to a human-machine interface (HMI) network. Dedicated HMI operator stations are assigned to each area, with an appropriate number of redundant stations providing backup in case of maintenance or breakdown. A development station permits tooling changes between campaigns to be carried out at the same time as systemiza-tion is carried out on the individual areas. A redundant set of historical data collection stations ensures that all of the data are collected and stored for both regulatory... 

Co., Richmond, Calif. Hexamethyleneimine (HMI) was purchased from Matheson Coleman Bell Co. S (Hexahydro-[2-I tC]azepine-l-car-bonyl)-N-acetyl-L-cysteine (molinate mercapturic acid) was provided by DeBaun et al. (12). Caprolactam was purchased from J.T,... 

The five major organosoluble metabolites in the water were molinate sulfoxide, 3- and 4-hydroxy molinate, 4-keto molinate, and keto hexamethyleneimine (keto HMI). The amount of each metabolite in tap water remained fairly constant (below 2%) throughout the 14 days. In water previously containing fish, molinate sulfoxide was 2.1% 4 days after treatment, while other metabolites remained below 2% for the first 7 days. By the 14th day, however, molinate sulfoxide totaled 12.8% and 4-hydroxy and 3-hydroxy molinate were 2.2 and 3.7%, respectively. 

In the presence of carp, molinate was rapidly transformed into more polar metabolites. Twenty-four hours after treatment, conversion of molinate to organosoluble metabolites was extensive (Table II). The proportion of molinate sulfoxide increased from 1.2% on day 1 to 10.2% by the 14th day. Molinate, hydroxylated at the 4 position, decreased from 10.8% to 4.6% in 14 days. However, 4-keto and 3-hydroxy molinate together gradually increased over the 14 days from 6.9% to 77.7%. Another metabolite, a keto HMI,... 

Molinate Metabolism in Carp Hepatic Mixed-function Oxidase System. Incubation of molinate with carp liver microsomes produced four major organosoluble metabolites (molinate sulfoxide, 3- and 4-hydroxy molinate, and keto HMI). Parameters affecting... 

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