Particular risk analysis advantages

Advantages brought about by the direct analysis of solid samples as compared with the analysis of dissolved samples include a shorter total analysis time (prior dissolution steps are not required), low cost (chemical reagents are not used), less risk of contamination and less destruction of the sample. In addition, some techniques can extract information about chemical speciation e.g. XPS provides information about oxidation states and chemical bonds) and spatial composition, i.e. information with lateral resolution allowing mapping of the surface and analysis with depth resolution, of particular interest for thin-film analysis. 

Methods for including the cost of capital in economic analyses have been discussed in Chap. 7. Although the management and stockholders of each company must establish the company s characteristic cost of capital, the simplest approach is to assume that investment of capital is made at a hypothetical cost or rate of return equivalent to the total profit or rate of return over the full expected life of the particular project. This method has the advantage of putting the profitability analysis of all alternative investments on an equal basis, thereby permitting a clear comparison of risk factors. This method is particularly useful for preliminary estimates, but it may need to be refined further to take care of income-tax effects for final evaluation. 

It will continue to be of considerable importance to establish a specific role for chromosome loss in tumor development. The analysis of aneuploidy in interphase cells of solid tumors using FISH will be greatly advantageous in this respect. For cancer risk assessment purposes, results from aneuploidy assays can be considered particularly useful when the mode of action of a chemical is known to result in chromosome loss or nondisjunction. 

This approach to analyze exonuclease ladders seems to be a particularly promising tool to determine rapidly the sequence of oligonucleotides. Compared to conventional methods, based on the laboratory-scale preparation of a large number of samples at different enzyme and substrate concentrations followed by MALDI-MS analysis, the microfluidics approach offers the advantage of saving time and material. Furthermore, due to the limited sample handling, the risks encountered when manipulating biomolecules are also reduced as well as that of sample contamination. 

Software System Hazard Analysis This type of analysis is conducted similar to a hardware system hazard analysis (SHA), analyzing software functional processing steps to determine whether they may have any particular hazardous effect on the system. The analysis utilizes a hazard-risk index to illustrate the severity of each potential failure. The main advantage to this method is in its ability to positively identify safety-critical hardware and software functions as well as consider the effect of the human element in system software operations. The results of the software SHA, which identifies single-point failures or errors within a system, can often be used to assist in the development of a software fault tree analysis or, to some degree, a system FMEA. However, as with the other various SWHA techniques briefly described above, this method is also time-consuming and costly to perform. 

This paper discusses the application of 2 popular methods of determining SIL requirements - risk graph methods and layer of protection analysis (LOPA) - to process industry installations. It identifies some of the advantages of both methods, but also outlines some limitations, particularly of the risk graph method. It suggests criteria for identifying the situations where the use of these methods is appropriate. 

Direct analysis using little or no sample preparation has the advantage of time saving and minimum risk of analytic loss. This technique has been applied for highly viscous liquids and has been examined for the determination of Ni (Brandao et al., 2006), Ni and V (Sdva et al., 2007) and Cu, Fe and V (Brandao et al., 2007) in oil samples. However there are some general problems such as volatility, flammability and immisdbility with water. In addition to the problems related to the complexity of the matrix, organic standards, which are indispensable in case of direct sample introduction, are unstable and there are no certified reference materials available for these samples. It is therefore necessary to compare the accuracy of the developed method with results obtained with independent technique, particularly with respect to the sample preparation... 

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