Error traps

All the worksheets in the GT Calculator files are supported by error detection macros, which trap and delete incorrect data entered into the input cells. For the case of the Characters from Orbits command button worksheet, only integer numbers of orbits may be input for a calculation of the permutation character and its direct sum components though for certain 

The complete set of local d-orbitals on a set of vertices generates a, tt and (5 characters under actions of the symmetry operations of the point group. The set of local f-orbitals generates a, n and 8 and characters, and so on. 

For technical reasons, your keyboard BACKSPACE button should not be used to correct errors made during data input. The default state of the input cells on all the calculator worksheets is that they contain the number zero. 

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Human factors are an extremely important part of inherently safer concepts. Processes should be designed to avoid error traps. Chapter 6 of this book presents a discussion of human factors as related to inherently safer design. 

Figure 1.11 Demonstration of the error trapping routines in the code controlling worksheet calculations activated through the Character from Orbits command button. Note that the second screen dump has been enhanced to emphasise that a non-integer entry was made, because the default format for the of orbits input cells is integer.

The usual error traps are present in the code controlling the direct-product calculations. In addition, you will be prompted should you forget to specify either or both components of the direct sums required to perform the calculation. A Print command button is available. 

Hospital B s experience is not unique. The net effect of the completion rate measure has been that it produces data which show that many actions are not completed within a specified time frame. This has, in some hospitals led senior managers to call into question the value of the walk rounds or to drive behaviour to focus on problems that can be fixed easily. Thus the lack of integration of human factors into hospital and medical device design and the allocation of staffing and resources gets put into an unresolvable box and remain latent conditions that continue to create error traps, inefficiencies and poor patient experience. 

Top management adopts a proactive stance toward patient safety. It does some or all of the following takes steps to identify recurrent error traps and removes them strives to eliminate the workplace and organization factors likely to provoke errors brainstorms new scenarios of failure conducts regular health checks on the organizational processes known to contribute to mishaps. 

Safety net Redundancy Risk management Error traps Error mitigation... 

When one takes a sample at the rate of 0.3 liter min from a stack discharging 2000 m min to the atmosphere, the chances for error become quite large. If the sample is truly representative, it is said to be both accurate and unbiased. If it is not representative, it may be biased because of some consistent phenomenon (some of the hydrocarbons condense in the tubing ahead of the trap) or in error because of some uncontrolled variation (only 1.23 gm of sample was collected, and the analytical technique is accurate to 0.5 gm) (1). 

Differential pressures and subatmospherie pressures should be measured by manometers with a fluid that is ehemieally stable when in eontaet with the test gas. Mereury traps should be used where neeessary to prevent the manometer fluid from entering the proeess piping. Errors in these instruments should not exeeed 0.25%. 

Existing facilities can contain many traps to cause human error. 

Catch decimal errors by software or procedure. For example, have the control system logic trap and prevent setpoint changes, for example, from 6% to 61%, when a change from 6.0 to 6.1% is intended. 

Many accidents, particularly on batch plants, have been due to runaway reactions, that is, reactions that get out of control. The reaction becomes so rapid that the cooling system cannot prevent a rapid rise in temperature, and/or the relief valve or rupture disc cannot prevent a rapid rise in pressure, and the reactor ruptures. Examples are described in the chapter on human error (Sections 3.2.1 e and 3.2.8), although the incidents were really due to poor design, which left traps into which someone ultimately fell. 

When steam pressures in the chest are near atmospheric, condensate can rise in the shell and drastically reduce avail-ahle surface—if the trap is too small to dump steam into the condensate return system or if the condensate return pressure is greater than the calculated chest pressure required. In these cases, the steam pressure will have to rise in the chest to overcome this error, if steam pressure is available. If not, the rehoiler will not deliver design flux. 

There have been several experimental studies of two-phase flow in which the holdup has been measured, either directly or indirectly. The direct method of measurement involves suddenly isolating a section of the pipe by means of quick-acting valves and then determining the quantity of liquid trapped.00111 Such methods are cumbersome and are subject to errors arising from the fact that the valves cannot operate instantaneously. Typical of the indirect methods is that in which the pipe cross-section is scanned by y-rays and the hold-up is determined from the extent of their attenuation.02 13141... 

Fig. 10-15 Organic carbon fluxes with depth in the water column normalized to mean annual primary production rates at the sites of sediment trap deployment. The undulating line indicates the base of the euphotic zone the horizontal error bars reflect variations in mean annual productivity as well as replicate flux measurements during the same season or over several seasons vertical error bars are depth ranges of several sediment trap deployments and uncertainities in the exact depth location. (Reproduced with permission from E. Suess (1980). Particulate organic carbon flux in the oceans - surface productivity and oxygen utilization, Nature 288 260-263, Macmillan Magazines.)...

C03-0151. Describe how the results of the analysis in Problem 3.104 would be affected by the following errors in operation of the apparatus. Which measurements would change, and in what direction How would that affect the calculation of the empirical formula (a) A limited supply of oxygen was provided, rather than excess oxygen (b) some of the H2 O leaked through the H2 O trap but was collected in the CO2 trap and (c) the H2 O trap functioned properly, but some of the CO2 leaked through the CO2 trap. 

Miller and Hawthorne [416] have developed a chromatographic method that allows subcritical (hot/liquid) water to be used as a mobile phase for packed-column RPLC with solute detection by FID, UV or F also PHWE-LC-GC-FTD couplings are used. Before LC elution the extract is dried in a solid-phase trap to remove the water. In analogy to SFE-SFC, on-line coupled superheated water extraction-superheated water chromatography (SWE-SWC) has been proposed [417]. On-line sample extraction, clean-up and fractionation increases sensitivity, avoids contamination and minimises sources of error. 

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