Heading error

The Cannon-Fenske viscometer (Fig. 24b) is excellent for general use. A long capillary and small upper reservoir result in a small kinetic energy correction the large diameter of the lower reservoir minimises head errors. Because the upper and lower bulbs He on the same vertical axis, variations in the head are minimal even if the viscometer is used in positions that are not perfecdy vertical. A reverse-flow Cannon-Fen ske viscometer is used for opaque hquids. In this type of viscometer the Hquid flows upward past the timing marks, rather than downward as in the normal direct-flow instmment. Thus the position of the meniscus is not obscured by the film of Hquid on the glass wall. 

Having the calculation in the procedure or readily available ensures accuracy and consistency. Retaining the calculation provides a record of the results and ensures the accuracy of the calculation. If the procedure users perform the calculation on scrap paper or even worse in their head, errors can occur. Additionally, unless auditors can access all of the data, such as the results of calculations, they will have difficulty determining what happened when une3q)ected results are obtained. 

Figure 8. Angular rate measurements (top), heading (middle) and heading error (bottom) with GNSS Compass as referenee for FOG and MEMS IMU in a dynamic scenario...

According to the simple formula, the maximum bubble pressure is given by f max = 27/r where r is the radius of the circular cross-section tube, and P has been corrected for the hydrostatic head due to the depth of immersion of the tube. Using the appropriate table, show what maximum radius tube may be used if 7 computed by the simple formula is not to be more than 5% in error. Assume a liquid of 7 = 25 dyn/cm and density 0.98 g/cm. ... 

Fc is plotted in Fig. 11-6. This figure is strictly applicable only to splitring, floadng-head construcdon but may be used for other situations with minor error. 

In the left upper corner of Figure 3.4.1, the centrifugal pump performance is shown. As ean be seen, the head generated depends on RPM but is independent of the flow, within a 10 % error, up to a eertain limit. The pressure staits to deeline when that point is reaehed at whieh the flow is high enough that the pump itself limits the flow beeause of its eross-section. 

In the case of the ship shown in Figure 1.3, the rudder and engines are the control inputs, whose values can be adjusted to control certain outputs, for example heading and forward velocity. The wind, waves and current are disturbance inputs and will induce errors in the outputs (called controlled variables) of position, heading and forward velocity. In addition, the disturbances will introduce increased ship motion (roll, pitch and heave) which again is not desirable. 

Fox s perfectionism is illustrated by an anecdote At a meeting held at ICI (his previous employer), Fox presented his final design for a two-mile cable transporter. Suddenly he clapped his hand to his head and exclaimed How could I have made such an error Then he explained to his alarmed colleagues I forgot to allow for the curvature of the Earth . 

LESF (Figure 3.4.5-5), exemplified for the large LOCA, is compared with SELF. Event tree headings are the refueling water storage tank (RWST) a passive component, an engineered safety system (SA-1) and four elements of the containment system. Other examples of the LESF method show human error in the event tree while the criteria for system success is usually in the tan It tree analysis. 

Many leaks have been discussed under other headings, including leaks that occurred during maintenance (Chapter 1), as the result of human error (Chapter 3), or as the result of overfilling storage tanks (Section 5.1). Other leaks have occurred as the result of pipe or vessel failures (Chapter 9), while leaks of liquefied flammable gas are discussed in Chapter 8 and leaks from pumps and relief valves in Chapter 10. 

The intention of this section is to provide a selection of case studies of varying complexity and from different stages of chemical process plant operation. The purpose of these case studies is to indicate that human error occurs at all stages of plant operation, and to emphasize the need to get at root causes. The case studies are grouped under a number of headings to illustrate some of the commonly recurring causal factors. Many of these factors will be discussed in later chapters. 

These relations do not hold closely for large impeller cuts, as the head and capacity drop a litde faster than the relations indicate. Allowance should be made by a trial-and-error approach when actually reducing an impeller size. Efficiency will remain nearly constant during all of the changes discussed. 

From Figure 12-65, by trial-and-error interpolation, when e = 0.7, ep = 0.735. Using ep in the horsepower equation, convert adiabatic head to polytropic head using Figure 12-67. 

Epilepsy may be defined as a permanent, recurrent seizure disorder. Examples of the known causes of epilepsy include brain injury at birth, head injuries, and inborn errors of metabolism, hi some patients, the cause of epilepsy is never determined. 

If the head and stem are situated at a distance of 14 diameters from each other as on the standard instrument,<4) the two disturbances are equal and opposite at a section 6 diameters from the head and 8 from the stem. This is, therefore, the position at which the static pressure orifices should be located. If the distance between the head and the stem is too great, the instrument will be unwieldy if it is too short, the magnitude of each of the disturbances will be relatively great, and a small error in the location of the static-pressure orifices will appreciably affect the reading. 

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