Procedures, performance-influencing factors

All critical errors and recovery points for task steps are recorded in accordance with the conventions of the PHEA and provide a valuable input to the specification of warnings and cautions for the design of procedures. In addition, various performance-influencing factors which contribute to the occurrence of critical errors can be identified which can provide input to the development of other error reduction measures such as training, and control panel design. 

Some of the performance-shaping factors (PSFs) affect a whole task or the whole procedure, whereas others affect certain types of errors, regardless of the tasks in which they occur. Still other PSFs have an overriding influence on the probability of all types of error in all conditions. 

HMI specifications and applied solutions as Piping and Instrumentation Diagrams (P ID), data formats, types of data obtained, ergonomics of control room and organizational factors directly influencing on operator performance and should be incorporated into HRA analysis. Under consideration should also be taken the performance shaping factors (PSFs), such as stress, estabUshed procedures affecting human operator performance, etc. 

A key factor for MD membranes is the fabrication procedures that influence the morphology and porosity of the membranes, thereby defining their performance efficiency. An exhaustive review on the progress in the production of poly(vinylidene fluoride) (PVDF) membranes was published by Liu et al. (2011). Since then, more than 100 publications have added more information and interpretation on the interplay of different parameters in the fabrication process of flat-sheet PVDF membranes. 

In many cases an optimized method may produce excellent results in the laboratory developing the method, but poor results in other laboratories. This is not surprising since a method is often optimized by a single analyst under an ideal set of conditions, in which the sources of reagents, equipment, and instrumentation remain the same for each trial. The procedure might also be influenced by environmental factors, such as the temperature or relative humidity in the laboratory, whose levels are not specified in the procedure and which may differ between laboratories. Finally, when optimizing a method the analyst usually takes particular care to perform the analysis in exactly the same way during every trial. 

MaintainabiUty is a characteristic of design, installation, and operation, usually expressed as the probabiUty that a system can be restored to specified operable conditions within a specified interval of time when maintenance is performed in accordance with prescribed procedures. The ease of fault detection, isolation, and repair are all influenced by system design and are principal factors contributing to maintainabiUty. Also contributing is the supply of spare parts, the supporting repair organization, and preventative maintenance practices. MaintainabiUty must be designed into the equipment. Some factors to consider foUow. 

As stated above, the design of an RDC contactor usually involves the performance of pilot tests due to the large number of factors whicF can influence performance. These pilot plant data must then be scaled-up to Rill commercial size. The following procedure is recommended. 

Procedure Set up an acoustic reactor in a light-proof cabinet with a photomultiplier (PM) tube positioned facing the cell as shown in Fig. 15.3a and b. Fill the cell with distilled water and close the cabinet. A potential should now be applied to the PM tube, the output (spectrally integrated) of which is produced on an oscilloscope (note that the ultrasound cell can easily be placed inside a commercial spectrometer in order to record the emission spectrum). Switch on the ultrasound and you should observe on the oscilloscope a change in voltage, directly proportional to the intensity of sonoluminescence emission. The following experiments can be performed to explore the different types of light emission and some of the factors that influence these emission processes. 

---