I/O system

In testing for equilibrium in the KCl-KBr-I O system (8), the analysis that follows initially assumes that all solids are at stoichiometric saturation with the aqueous solution. 

Figure 40. Representation of Mg-Si-i O system in terms of the activity of Mg, H+ and aqueous silica (25°C and atmospheric pressure). Solid line boundaries are taken from Wollast, et al., (1968), dashed lines are deduced boundaries based upon the data of Siffert (1962). The appearance of sepiolite is found only above pH 8 and thus the log Mg +/H+ ratio is not valid for all Mg +-H+ values. There are no specified extensive variables or inert components in the system described. Br = brucite M03 = trioctahedral montmorillonites Sep = sepiolite T = talc.

Field operating personnel have access to the computer through a man-machine input/output (I/O) system located in the Field office. The I/O equipment consists of a cathode ray tube (CRT) with attached keyboard, a card reader and a printer for permanent copy of transmitted information. The I/O system supplies all alarms and operating data needed to monitor production operations. 

In addition to CPC, another concept used at Conroe is computer data collection (CDQ. Normally, CDC is implemented for conventional tank battery operations where CPC equipment investments are not economically attractive. In contrast to CPC, the CDC system requires field personnel to enter production volume and well test data manually through the I/O system. Once this data is entered, it is processed by the computer similar to the processing of CPC data. The major CPC features excluded in the CDC concept are alarm detection, automatic well testing, and production measurement. 

Integrated volumes of both oil and gas arc obtained from net-oil and gas-flow analog computer measurements. Saltwater measurements are obtained from digital signals generated by turbine meters. Notable changes in metered volumes are output by the I/O system for surveillance of possible meter upsets. 

Figure 2. Portion of Eh-pH diagram for As-I O system, showing effects of increasing temperature from 25 to 100 °C. Free energy of formation data from Ref. 16 were used in the calculations.

Currently, remote I/O systems of several manufacturers are available for operation in zone 1 or Division 1. To a large extent, these systems are based upon the technology of intrinsic safety. The power supply only is designed according to another type of protection, e.g. flameproof enclosure - d A remote I/O suitable for hazardous areas may be an integration of input (I) and output (O) assembly units of automation systems and of Ex i-isolators of classic design. The installation may be made in a hazardous area and supersede the classic field distribution box (terminal box). Standardized fieldbus systems may be used for data transmission from/to the automation system. These remote I/O systems for hazardous areas are characterized as follows ... 

Remote I/O systems are also available which can be installed in a safe area or in zone 2/Division 2 only, although they are equipped with intrinsically safe inputs and outputs. 

Typically, a remote I/O system is a modular assembly (see Fig. 6.210). In this figure, the power supply, the connection to the fieldbus, the internal bus (power and data line) are shown as well as input and output modules. Input and... 

Figure 6.210 Schematic circuit diagram of a remote I/O system.

In the following, advantages and disadvantages of remote I/O systems are summarized ... 

Manufacturers succeed increasingly to transform this idea into marketable products, in particular remote I/O systems and fieldbus products. 

In more recent times, the n-concept has been extended to applications in the field of process control. In Table 11.2, a comparison is given between two CPU and power modules for remote I/O systems, one intended for zone 1 installation, the second for zone 2 application. Obviously, the zone 2 concept with a special protection technique offers some financial and technical benefits compared with a zone 1 apparatus which may be used in zone 2 as a matter of course. 

Figure 11.5 CPU and power module for remote I/O systems, zone 1 application (for technical data see Table 11.2)...

Fig. 18 TEM micrographs of PS-6-P4VP(MSA)i.o(PDP)i.o system with Mw,ps =32 900 g/ mol, Mw,P4VP = 8100g/mol, weight fraction P4VP(MSA)i.o(PDP)i.o is 0.54. a At room temperatme a lamellar-m-lamellar structure, b at T = 170 °C P4VP cylinders, and c at T = 210 °C a spherical morphology. P4VP shows dark due to I2 staining [132]...

For measurable characteristics, the process of translating customer requirements into internal requirements can be pictured in terms of an input/output model. Take as an example the customer requirement that the dosage of a vial of drug contain 15% of the labeled dosage of 10 mg. Dosage is the external requirement and will be referred to as an output variable. A vial s dosage depends on the fill volume of the vial and the concentration of the solution. These are the internal requirements and will be referred to as input variables or factors. The input/output (I/O) system is shown in Figure 1. 

Computers have an input/output (I/O) system, which communicates with humans and with other devices, including other computers. I/O devices include keyboards, monitors, printers, and speakers. 

REMTIAL - instantaneously move I O system to a different point in the trajectory... 

Safety-related controllers in conjunction with safety or fail safe I/O modules are used for critical and hazardous applications where an incident can result in danger to persons, and/or damage to plant and environment. These safety-related controllers can work with the safety-related distributed I/O system (may be with internal verification for input or output via safety switches as described in Clause 5.0.1—safe PLC approach), or directly with fail-safe transmitters cormected via the fieldbus. These controllers are supposed to detect faults both in the process and their own internal (self-diagnosis) to the system. It is the duty of the same to automatically set the plant to a safe state in the event of a fault. These controllers need to work in multitasking environment — may be in a mix of standard BPCS or safety-related applications, if integrated operation is permitted by the end-user. The programs of BPCS and SIS must be functionally separate, so that faults in BPCS applications have no effect on safety-related applications and vice versa. Special tasks with very short response times can also be implemented [14]. For safety applications controllers and I/O modules need to individually certified by third party and to comply SIL 2/SIL 3 (as the case may be — SIL 4 only for nuclear application) as per lEC 61508. For safety-related applications a few restrictions are followed such as ... 

The study of computer architecture amounts to analyzing two basic principles, performance and cost for a set of computer architecture alternatives that meet functionality requirements. This appears to be straightforward when considered at a general level, but when these topics are looked at in detail the water can become muddy. If a systematic approach is used the concepts can be straightforward. Fortunately, central processing units, memory hierarchy, I/O systems, etc., are layered, and these layers may be considered as levels of abstractions. Each level of abstraction has its own abstractions and objects. By studying aspects of computer science in this fashion, it is possible to censor out details that are irrelevant to the level of abstraction being considered and to concentrate on the task at hand. 

The I/O system is a crucial part of any computer system, but it will not be discussed in greater detail in this article. 

This chapter on nonlinearity quantification introduces the basic concepts of nonlinearity measures and shows the insights into a system s behaviour and structure they can deliver. After introducing the concept of nonlinearity measures for general I/O-systems, the presentation will focus on the control-relevant nonlinearity characterization, i.e. the relevance of the system nonlinearity with respect to controller design. 

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