Consequence analysis reduction

Laguna Verde unit one during a startup after a scram in cycle four, experienced such kind of instabilities, with peak to peak of the order of 10% of rated power, this unexpected performance, required an analysis of the core stability in the power flow map. Consequences such reduction of the operational area in the power flow map was established, changes to the procedures for shift speed of re-circulation pump were launched. Specific operator training was developed. 

Using the consequence analysis results, the bottleneck situations have to be examined specifically to work out mitigating measures. For a reduction in the contribution of external interference measures are for example, the use of concrete slabs or warning tapes and agreements with landowners about land utilization. Other types of measures are still to be examined. 

Consequence analysis plays an important part in Chemical Process Quantitative Risk Analysis (CPQRA). CPQRA is a methodology designed to provide management with a tool to help evaluate overall process safety in the chemical process industry (CPI). Management systems such as engineering codes, checklists and process safety management (PSM) provide layers of protection against accidents. However, the potential for serious incidents cannot be totally eliminated. CPQRA provides a quantitative method to evaluate risk and to identify areas for cost-effective risk reduction. 

Observations of smooth spalls in iron provided an early, dramatic demonstration of the importance of release wave behaviors. In 1956, Dally [61E01] reported the existence of remarkably smooth fracture surfaces in explosively compressed steel. The existence of these smooth spalls was a sensitive function of the sample thickness. Analysis and experiments by Erkman [61E01] confirmed that the smooth spalls were associated with interaction of release-wave shocks and shocks from reduction of pressure at free surfaces. These release shocks are a consequence of differences in compressibility at pressures just below and just above the 13 GPa transformation. 

For those errors with significant consequences where recovery is unlikely, the qualitative analysis concludes with a consideration of error reduction strategies that will reduce the likelihood of these errors to an acceptable level. These strategies can be inferred directly from the results of the PIF analysis, since this indicates the deficiencies in the situation which need to be remedied to reduce the error potential. 

The Chemical Process Industry (CPI) uses various quantitative and qualitative techniques to assess the reliability and risk of process equipment, process systems, and chemical manufacturing operations. These techniques identify the interactions of equipment, systems, and persons that have potentially undesirable consequences. In the case of reliability analyses, the undesirable consequences (e.g., plant shutdown, excessive downtime, or production of off-specification product) are those incidents which reduce system profitability through loss of production and increased maintenance costs. In the case of risk analyses, the primary concerns are human injuries, environmental impacts, and system damage caused by occurrence of fires, explosions, toxic material releases, and related hazards. Quantification of risk in terms of the severity of the consequences and the likelihood of occurrence provides the manager of the system with an important decisionmaking tool. By using the results of a quantitative risk analysis, we are better able to answer such questions as, Which of several candidate systems poses the least risk Are risk reduction modifications necessary and What modifications would be most effective in reducing risk ... 

A difficulty in the analysis of reactions suspected to take place with concerted movement of atoms lies in the irreversibility of most of the processes and the consequent impossibility of characterizing rates at the reversible potential. An approach which has been suggested is the comparison of the substituent effects of appropriate electrode reductions and homogeneous reactions as in the example (Marcus, 1968)... 

The rotors can be preloaded with lyophilized reagents, which can be dynamically dissolved by the addition of buffer to the spinning rotor. Multiple samples can then be introduced into each of the radial cuvettes, or a single sample can be dynamically apportioned between the multiple cuvettes, each of which contain reagents for a different enzyme reaction. Consequently, multiple samples can be monitored for the same enzyme activity, or several different enzyme activities can be measured for the same sample. The very fast data reduction offered by the online computer provides the operator with printed results as soon as the analysis is complete. This approach provides highly precise data (Table II). 

As a consequence of this short discussion, we can conclude that the shapes of the distribution obtained by the Warren-Averbach analysis may be less reliable as the results can be strongly influenced by the method chosen for data reduction and treatment. On the contrary, the average crystallite dimension is very stable and it is almost independent of the adopted analytical method. 

As a consequence of the inhalation of mineral dusts, infiltration into the lung of inflammatory phagocytic cells, namely PMN and macrophages, occurs (Rola-Pleszczynski et al., 1984). Analysis of the cell populations of the rat pleural cavities after injection with asbestos and silica dust also showed both degranulation and reduction of the mast cell population (Edwards etal., 1984), and it is of interest to note that histamine augments the particle-stimulated generation of macrophage superoxide production (Diaz et al., 1979). 

By automation one can remove the variation of the analysis time or shorten the analysis time. Although the variation of the analysis time causes half of the delay, a reduction of the analysis time is more important. This is also true if, by reducing the analysis time, the utilization factor would remain the same (and thus q) because more samples are submitted. Since p = AT / lAT, any measure to shorten the analysis time will have a quadratic effect on the absolute delay (because vv = AT / (LAT - AT)). As a consequence the benefit of duplicate analyses (detection of gross errors) and frequent recalibration should be balanced against the negative effect on the delay. 

Analysis of Table II shows discrepancies in the hardness and stress behavior of a-C(N) H films. Although all the works reported a clear stress reduction upon nitrogen incorporation, the hardness sometimes is quoted as almost constant, or on the other hand clearly decreasing. In addition to the possible effect of different deposition methods and conditions, it can be easily seen that the differences in hardness testing methods are the major source for discrepancies. Constant hardness behavior is only reported with the use microindentation methods, like Vickers and Knoop microhardness. On the other hand, the use of low-load nanoindentation methods always led to a nitrogen-induced decrease in hardness. This is basically the consequence of two factors. The first one is the higher penetration... 

The most serious problem with input analysis methods such as PCA that are designed for dimension reduction is the fact that they focus only on pattern representation rather than on discrimination. Good generalization from a pattern recognition standpoint requires the ability to identify characteristics that both define and discriminate between pattern classes. Methods that do one or the other are insufficient. Consequently, methods such as PLS that simultaneously attempt to reduce the input and output dimensionality while finding the best input-output model may perform better than methods such as PCA that ignore the input-output relationship, or OLS that does not emphasize input dimensionality reduction. 

The effect of NO exposure time on the time at which the N2 and N2O signals attain a maximum is shown in Fig. 16. It is seen that the model of NO reduction predicts that N2 formation peaks about 0.5 s after the peak in the N2O formation and that the peak times for both products decline by about 0.5 s as the NO exposure time is increased from 5 to 30 s. These trends are in good agreement with the data. It should be noted that since a product analysis could be taken only once every 0.5 s, it was not possible to determine product peak positions with an accuracy of better than 0.5 s. Consequently, both the predicted difference between... 

The what-if analysis method may simply generate a list of questions and answers about the process. However, it usually results in a tabular listing of hazardous situations, their consequences, safety levels, and possible options for risk reduction. 

Risk is defined as a measure of human injury, environmental damage, or economic loss in terms of both the incident likelihood (probability) and the magnitude of the loss or injury (consequence) (AICHE/CCPS, Guidelines for Chemical Process Quantitative Risk Analysis, 2d ed., American Institute of Chemical Engineers, New York, 2000, pp. 5-6). It is important that both likelihood and consequence be included in risk. For instance, seat belt use is based on a reduction in the consequences of an accident. However, many people argue against seat belts based on probabilities, which is an incorrect application of the risk concept. 

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