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Maximum method

The effect of standardization of the features by use of the minimum/maximum method is demonstrated in Fig. 5-2. [Pg.142]

The standardization of objects by use of minimum/maximum method is outlined in Fig. 5-3. By this procedure values of all the features of one object were standardized between zero and one. Minimum values of each object were set to zero and maximum values to one. This particularly affects the shape of the circle because it has nearly constant values in each variable apart from the scattering. This scattering is now the character of this figure. The square has its maximum values in the diagonals, features 2, 4,... [Pg.143]

If a reasonable opportunity exists (based on common belief and experience) to improve the method variation to one-fourth or preferably less of the specification interval, this effort should be made. In the example of a drug product where the specification is 95%-105% with a target of 100%, then the maximum method variation must be less than 1.67% however, if the method variation is above 1.25%, efforts should be made to reduce its variation. Ideally, the method variation should not be greater than 2.0% even if the specification range is wider than 10%. The 2.0% maximum method variation requirement does not apply to tests where the variation of the method is substantially confounded with variation of the product being measured. [Pg.93]

Zero Coverage. The peaks at Infinite dilution were slightly skewed (skew ratio 0.8), with virtually no dependence of retention volume on Injection size. Instead of the peak maximum method, retention volumes were measured by the method proposed by Conder and Young (32). To ensure that the adsorption of n-alkanes on carbon fibers was taking place under equilibrium conditions, the flow rate was varied In the range 20 to 32 cm3 min-1. The net retention volumes were essentially Independent of flow rate. [Pg.173]

Isotherm Measure by frontal analysis, perturbation Measure by peak-maximum method Measure with ECP... [Pg.255]

With the ultimate objective of maximum method robustness and ruggedness in mind, selection of the appropriate stationary phase is... [Pg.445]

In the case of perfect symmetric peaks, the retention time can be determined directly from the peak maximum method, which is the simplest and most common. The peak maximum method is useful for determination of retention time if the skewness ratio is 0.7-1.3 [15]. The skewness ratio is defined as the ratio of tangent slope to the peak leading part and tangent slope to the peak tailing part whereas both tangents are drawn in the inflexion points. In such cases the skewness ratio is our of this interval, Ir is obtained from the first-order moment method or the Conder and Young method. Between these two methods, Conder and Young is recommended [16] ... [Pg.530]

The defuzzification process creates a single assessment from the fiizzy cmiclusion set expressing the risk associated with the event, so that corrective actions can be prioritised. Several defuzzification techniques have been developed (Runkler and Glesner (1993)). One conunon technique is the weighted mean of maximum method, which is illustrated here. This technique averages the points of maximum possibility of each fuzzy conclusion, wei ted by their degrees of truth. Hence, if the conclusion fixrm the risk evaluation phase is, for example, 0.5 Low, 0.1 Low and 0.5 Mod, the maximum value for each linguistic term is taken. This reduces the conclusion to 0.5 Low and 0.5 Mod to be defuzzified. [Pg.131]

The method used here is based on a general application of the maximum-likelihood principle. A rigorous discussion is given by Bard (1974) on nonlinear-parameter estimation based on the maximum-likelihood principle. The most important feature of this method is that it attempts properly to account for all measurement errors. A discussion of the background of this method and details of its implementation are given by Anderson et al. (1978). [Pg.97]

When there is significant random error in all the variables, as in this example, the maximum-likelihood method can lead to better parameter estimates than those obtained by other methods. When Barker s method was used to estimate the van Laar parameters for the acetone-methanol system from these data, it was estimated that = 0.960 and A j = 0.633, compared with A 2 0.857 and A2- = 0.681 using the method of maximum likelihood. Barker s method uses only the P-T-x data and assumes that the T and x measurements are error free. [Pg.100]

In the maximum-likelihood method used here, the "true" value of each measured variable is also found in the course of parameter estimation. The differences between these "true" values and the corresponding experimentally measured values are the residuals (also called deviations). When there are many data points, the residuals can be analyzed by standard statistical methods (Draper and Smith, 1966). If, however, there are only a few data points, examination of the residuals for trends, when plotted versus other system variables, may provide valuable information. Often these plots can indicate at a glance excessive experimental error, systematic error, or "lack of fit." Data points which are obviously bad can also be readily detected. If the model is suitable and if there are no systematic errors, such a plot shows the residuals randomly distributed with zero means. This behavior is shown in Figure 3 for the ethyl-acetate-n-propanol data of Murti and Van Winkle (1958), fitted with the van Laar equation. [Pg.105]

The maximum-likelihood method is not limited to phase equilibrium data. It is applicable to any type of data for which a model can be postulated and for which there are known random measurement errors in the variables. P-V-T data, enthalpy data, solid-liquid adsorption data, etc., can all be reduced by this method. The advantages indicated here for vapor-liquid equilibrium data apply also to other data. [Pg.108]

The maximum-likelihood method, like any statistical tool, is useful for correlating and critically examining experimental information. However, it can never be a substitute for that information. While a statistical tool is useful for minimizing the required experimental effort, reliable calculated phase equilibria can only be obtained if at least some pertinent and reliable experimental data are at hand. [Pg.108]

VLE data are correlated by any one of thirteen equations representing the excess Gibbs energy in the liquid phase. These equations contain from two to five adjustable binary parameters these are estimated by a nonlinear regression method based on the maximum-likelihood principle (Anderson et al., 1978). [Pg.211]

MAIN PROGRAM AND DRIVER FOR FITTING BINARY VLF DATA USING METHOD EASED ON THE MAXIMUM LIKELIHCOO PRINCIPLE ONLY CONTROL VARIABLES APE READ IN THIS ROUTINE. [Pg.229]

A simple method to achieve this is based on the fact that for any value of R there is a maximum asymptotic value for P, say, P axi which is given as Ft tends to - c and is given by ... [Pg.224]

The pinch design method developed earlier followed several rules and guidelines to allow design for minimum utility (or maximum energy recovery) in the minimum number of units. Occasionally, it appears not to be possible to create the appropriate matches because one or other of the design criteria cannot be satisfied. [Pg.372]

The most widely used reactions are those of electrophilic substitution, and under controlled conditions a maximum of three substituting groups, e.g. -NO2 (in the 1,3,5 positions) can be introduced by a nitric acid/sul-phuric acid mixture. Hot cone, sulphuric acid gives sulphonalion whilst halogens and a Lewis acid catalyst allow, e.g., chlorination or brom-ination. Other methods are required for introducing fluorine and iodine atoms. Benzene undergoes the Friedel-Crafts reaction. ... [Pg.55]

As stated above for the TBP distillation, petroleum cannot be heated above 340°C without its molecules starting to crack. Because of this, analytical distillation of heavy fractions is done according to the ASTM D 1160 method for petroleum materials that can be partially or completely vaporized at a maximum temperature of 400°C at pressures from 50 to 1 mm of mercury (6.55 to 0.133 kPa). [Pg.19]

The advantages of this method are its rapidity (maximum duration, 70 min), the small quantity of sample required (1 pi), and its ease of automation. [Pg.22]

Adaptations of this method have been proposed in order to take into account the band displacement due either to substitution on the aromatic ring, or to chains of different lengths. The variations consist, instead of measuring the absorbance at maximum absorption, of an integration of the absorbance curve over a specified range (Oelert s method, 1971). More exact, this method is used less often mainly because the Brandes method is simpler... [Pg.61]

The classical computer tomography (CT), including the medical one, has already been demonstrated its efficiency in many practical applications. At the same time, the request of the all-round survey of the object, which is usually unattainable, makes it important to find alternative approaches with less rigid restrictions to the number of projections and accessible views for observation. In the last time, it was understood that one effective way to withstand the extreme lack of data is to introduce a priori knowledge based upon classical inverse theory (including Maximum Entropy Method (MEM)) of the solution of ill-posed problems [1-6]. As shown in [6] for objects with binary structure, the necessary number of projections to get the quality of image restoration compared to that of CT using multistep reconstruction (MSR) method did not exceed seven and eould be reduced even further. [Pg.113]

In the Maximum Entropy Method (MEM) which proceeds the maximization of the conditional probability P(fl p ) (6) yielding the most probable solution, the probability P(p) introducing the a priory knowledge is issued from so called ergodic situations in many applications for image restoration [1]. That means, that the a priori probabilities of all microscopic configurations p are all the same. It yields to the well known form of the functional 5(/2 ) [9] ... [Pg.115]

Systems, based on a method of inspection of slice by slice, in a number of cases allow to solve put problems. But for obtaining of higher resolution it is necessary to have an opportunity to increase number of inspected slices. It results in significant increasing of collection data time that is inadmissible in some applications. Besides this, the maximum allowable number of researched slices is rigidly limited by hardware opportunities of tomographs, and also by level of emission of x-ray sources. [Pg.216]

The changing of welding method to the vibro-contact has caused a lowering of own tensile stress to 180 MPa, whereas in the joint the stress is close to zero After annealing the maximum value of stress has reached 20 MPa... [Pg.387]

Let us consider the calculation of sensitivity threshold in the case when the cracks are revealing by PT method. Constant distance H between crack s walls along the whole defect s depth is assumed for the simplicity. The calculation procedure depends on the dispersity of dry developer s powder [1]. Simple formula has to be used in the case when developer s effective radius of pores IC, which depends mainly on average particle s size, is smaller than crack s width H. One can use formula (1) when Re is small enough being less than the value corresponding maximum sensitivity (0,25 - 1 pm). For example. Re = 0,25 pm in the case when fine-dispersed magnesia oxide powder is used as the developer. In this case minimum crack s width H that can be detected at prescribed depth lo is calculated as... [Pg.614]

The maximum bubble pressure method is good to a few tenths percent accuracy, does not depend on contact angle (except insofar as to whether the inner or outer radius of the tube is to be used), and requires only an approximate knowledge of the density of the liquid (if twin tubes are used), and the measurements can be made rapidly. The method is also amenable to remote operation and can be used to measure surface tensions of not easily accessible liquids such as molten metals [29]. [Pg.18]

Correction Factors for the Maximum Bubble Pressure Method (Minimum Values of Xjr for Values of r/a from 0 to 1.50)... [Pg.19]


See other pages where Maximum method is mentioned: [Pg.238]    [Pg.285]    [Pg.469]    [Pg.177]    [Pg.391]    [Pg.60]    [Pg.60]    [Pg.991]    [Pg.439]    [Pg.124]    [Pg.72]    [Pg.238]    [Pg.285]    [Pg.469]    [Pg.177]    [Pg.391]    [Pg.60]    [Pg.60]    [Pg.991]    [Pg.439]    [Pg.124]    [Pg.72]    [Pg.411]    [Pg.7]    [Pg.109]    [Pg.114]    [Pg.171]    [Pg.244]    [Pg.17]    [Pg.35]   
See also in sourсe #XX -- [ Pg.176 ]




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