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Uncertainty Calculus

Keywords Dimensional metrology Uncertainty calculus Monte Carlo method Optical Measuring Machine. [Pg.95]

The different statistical character of the three variables becomes most clear in the different uncertainties of the calibration and evaluation lines. Notwithstanding the fundamental differences between xstandard and xsampiey the calculation of the calibration coefficients is carried out by regression calculus. [Pg.152]

In order to propagate the uncertainties on (143Nd/144Nd)s and (147Sm/144Nd)s towards TDM, we first need to compute the partial derivatives of TDM relative to these two variables. Using the rules of calculus, we get... [Pg.227]

Error analysis. The mathematical analysis done to show quantitatively how uncertainties in data produce uncertainty in calculated results, and to find the sizes of the uncertainty in the results. [In mathematics the word analysis is synonymous with calculus, or a method for mathematical... [Pg.157]

The only satisfactory description of uncertainty is probability. By this I mean that every uncertainty statement must be in the form of a probability that several uncertainties must be combined using the rules of probability and that the calculus of probabilities is adequate to handle all situations involving uncertainty. Probability is the only sensible description of uncertainty and is adequate for all problems involving uncertainty. All other methods are inadequate... that can be done with fuzzy logic, belief functions, upper and lower probabilities, or any other alternative to probability, can better be done with probability. [Pg.57]

The transmittance for minimum relative error can be derived from Beer s law by calculus, assuming that the error results essentially from the uncertainty in reading the instrument scale and also that the absolute error in reading the transmittance is constant, independent of the value of the transmittance. The result is the prediction that the niinimum relative error in the concentration theoretically occurs when T = 0.368 or A = 0.434. [Pg.502]

Our problem is to take the uncertainties in x, X2, and so on, and calculate the uncertainty in y, the dependent variable. This is called the propagation of errors. If the errors are not too large, we can take an approach based on a differential calculus. The fundamental equation of differential calculus is Eq. (7.9),... [Pg.331]

Calculus of the numerical value of the potential of a bubble is an extremely difficult problem. This potential is formally the electrostatic potential at the plane of slip, but there is a high uncertainty about the location of this plane. As a first approximation, it is assumed to be located to one water molecular diameter away from the plane of charge or at a total distance of approximately 0.4 nm from the air-water interface. If we suppose the bubble surface is charged, potential could be evaluated using the Poisson equation ... [Pg.505]

The second qualifier is that when an equation of state converts input to output, the latter should be viewed as an estimate of an average value. That is to say, the probability issues raised in Figure 3.5 are not apparent in the equations taken at face value. Yet their approximation nature extends beyond using only a few parameters to address molecular-level forces and the physical uncertainties surrounding R. Unlike functions encountered in calculus books, for example ... [Pg.68]

If the relative concentration uncertainty is given by Equation 13-13, use calculus to show that the minimum uncertainty occurs at 36.8% T. What is the absorbance that minimizes the concentration uncertainty Assume that is independent of concentration. [Pg.191]

Starting from sixteen century onwards, the probability theory, calculus and mathematical formulations took over in the description of the natural real world system with uncertainty. It was assumed to follow the characteristics of random uncertainty, where the input and output variables of a system had numerical set of values with uncertain occurrences and magnitudes. This implied that the connection system of inputs to outputs was also random in behavior, i.e., the outcomes of such a system are strictly a matter of chance, and therefore, a sequence of event predictions is impossible. Not all uncertainty is random, and hence, cannot be modeled by the probability theory. At this junction, another uncertainty methodology, statistics comes into view, because a random process can be described precisely by the statistics of the long run averages, standard deviations, correlation coefficients, etc. Only numerical randomness can be described by the probability theory and statistics. [Pg.93]

The risk is very often equated with a kind of uncertainty. In this case, the risk is determined as a combination of the probability of failure events occurrence and consequences of these events, and uncertainties, whether those events will occur and what will be the consequences. Traditionally, failure risk modelling in CWSS is applied to the calculus of probability. It requires a statistically representative data set of faults. Often, in practice, this condition can t be met. Very often the data are derived from the experts whose knowledge is incomplete or uncertain. In this case, the use of arbitrary probability and its distributions leads to unreliable results (Tchorzewska-Cieslak 2010). [Pg.1475]

These concepts have been introduced to analyze the impact of natural phenomena on humans and their elfects are quantified using mathematical tools, for example, the probability calculus and evaluation of errors and uncertainties (Marzocchi et al. 2010 Albarello 2013). [Pg.60]

What is the cause of this uncertainty We noted earlier that x and P are related and have a mutual effect. Another way to quantify the effect of position and momentum is by using a commutator. In real arithmetic and algebra with real numbers, we are used to interchanging the order of factors as in 2x3 = 3x2 = 6, that is the commutator [3,2] = 0, but when we use calculus operators that interchange of order may not work. Let us define a quantity called the commutator as a bracket that represents the amount by which interchanging the order of two successive operators makes a difference (on some... [Pg.242]

The uncertainty of risk analysis—the fact that the data do not provide unique answers—allows for a range of perceptions about the nature of chemical hazards and their effects on worker health.. . . Some place concerns about risk within a calculus of economic viednlity others see risk from the point of view of those exposed to hazards. Each view has implications for responsibility and control. ... [Pg.99]

So far, we have only discussed dose extrapolation for non-Ccmcer chemicals. The same uncertainties discussed for dose extrapolation of non-cancer effects cu e also relevant for cancer effects. Mathematical models are typically used to extrapolate relationships from dose and cancer incidence established using high laboratory doses to those at low doses. These models can range from relatively simple linear equations (e.g., a straight line is assumed to represent the relationship) to complex mathematical solutions that involve exponential terms and knowledge of calculus. These models differ in their complexity based on the amount of information known about how a chemical causes cancer. Since the process of cancer development is complex, it is not surprising that some of the models used to describe the relationships between dose and response are also complex. [Pg.104]


See other pages where Uncertainty Calculus is mentioned: [Pg.350]    [Pg.63]    [Pg.287]    [Pg.17]    [Pg.321]    [Pg.117]    [Pg.40]    [Pg.126]    [Pg.44]    [Pg.366]    [Pg.366]    [Pg.223]    [Pg.312]    [Pg.324]    [Pg.191]    [Pg.243]    [Pg.222]    [Pg.223]    [Pg.225]    [Pg.13]    [Pg.1094]    [Pg.3838]    [Pg.216]    [Pg.232]   
See also in sourсe #XX -- [ Pg.95 ]




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