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What is Data Normalization

Data normalization is a method used to understand the performance of the membranes in an RO system (see Chapters 11.3 and 12). Performance, namely permeate flux, salt rejection, and pressure drop, are all functions [Pg.420]


Normal Distribution of Observations Many types of data follow what is called the gaussian, or bell-shaped, curve this is especially true of averages. Basically, the gaussian curve is a purely mathematical function which has very specif properties. However, owing to some mathematically intractable aspects primary use of the function is restricted to tabulated values. [Pg.490]

Once this initial data has heen recorded, a running log will indicate the performance under service conditions. As the load and amhient conditions change, the plant operators will he ahle to monitor the day-to-day conditions. This estahlishes normal running. Only hy a clear understanding of what is normal can the abnormal be detected. [Pg.337]

Unfortunately, a few papers are known where normal stresses during shear flow of filled polymers were measured directly. Here an additional problem is connected with the solution of the problem what is considered a one-valued measure of elasticity of a material and under what conditions to compare the measured values of normal stresses. Moreover, the data at hand often represent rather a contradictory picture. [Pg.92]

The material strength determined is the minimum required, not the average or maximum, which is what is normally provided on manufactures published data sheets. [Pg.129]

All the above solvolysis data are rationalized by the process depicted in Scheme 1. What is important for our consideration here is that a solvolytically produced bromonium ion of a "normal" olefin has been shown to react in both MeOH and HOAc by preferential attack of Br- on Br" ". This simple set of experiments might be taken as indicating bromonium ion reversal during electrophilic addition of Br2 to olefins is more prevalent than was originally believed. [Pg.126]

The possibility of obtaining single crystal diffraction patterns from regions of very small diameter can obviously be an important addition to the means for investigating the structures of catalytic materials. The difficulty arises that data on individual small particles is usually, at best, merely suggestive and at worst, completely meaningless. What is normally required is statistical data on the relative frequencies of occurrence of the various structural features. For adequate statistics, it would be necessary to record and analyse very large numbers of diffraction patterns. [Pg.337]

Up to now, all of the BN hydrogenation data was in the absence of NH3 and Figure 57.24 shows the effects of adding NH3 to the reaction mixture for the Ni and Mo promoted Ni catalysts either with or without FT. The amounts of FT were 1.33 mmol H2CO per g of Ni and 2.0 mmol H2CO per g of Mo promoted Ni, because the BA yields for these catalysts were the highest at these FT levels in the absence of NH3. The amount of NH3 added to these reactions was 10 ml of a 32 wt.% aqueous NH3 solution and this is relatively much lower than what is normally added to... [Pg.525]

Since this is a new chemical, all that is known is the chemical process for making it, its normal boiling point, and its chemical formula. The only source of information is the chemist who discovered it. The process engineering study will determine the production costs, identify the most costly steps involved, and decide what further data must be obtained to ensure that the proposed process will work. The production costs are needed to determine if the new product can compete monetarily with tetraethyl lead and other additives. [Pg.11]

The symmetry and simplicity of the matrix C (and hence the extreme rapidity of the FFT) is determined by the particular order employed in both the input vector / and the output F. Thus, both sets of data must be rearranged from what would be normally expected. While this problem represents an inconvenience for a programmer, it is carried out automatically in available programs. Although it would probably go un-noticed by the user, it is important for him or her to understand the fundamental algorithm of the FFT, which is based on the inverse binary order explained here. [Pg.385]

Now we ask ourselves the question If we calculate the standard deviation for a set of data (or errors) from these two formulas, will they give us the same answer And the answer to that question is that they will, IF (that s a very big if , you see) the data and the errors have the characteristics that statisticians consider good statistical properties random, independent (uncorrelated), constant variance, and in this case, a Normal distribution, and for errors, a mean (fi) of zero, as well. For a set of data that meets all these criteria, we can expect the two computations to produce the same answer (within the limits of what is sometimes loosely called Statistical variability ). [Pg.427]

In Chapters 63 through 67 [1-5], we devised a test for the amount of nonlinearity present in a set of comparative data (e.g., as are created by any of the standard methods of calibration for spectroscopic analysis), and then discovered a flaw in the method. The concept of a measure of nonlinearity that is independent of the units that the X and Y data have is a good one. The flaw is that the nonlinearity measurement depends on the distribution of the data uniformly distributed data will provide one value, Normally distributed data will provide a different value, randomly distributed (i.e., what is commonly found in real data sets) will give still a different value, and so forth, even if the underlying relationship between the pairs of values is the same in all cases. [Pg.459]

Social norms. Data about what is normal drug use for peers. [Pg.134]

These same analysis techniques can be applied to chemical imaging data. Additionally, because of the huge number of spectra contained within a chemical imaging data set, and the power of statistical sampling, the PLS algorithm can also be applied in what is called classification mode as described in Section 8.4.5. When the model is applied to data from the sample, each spectrum is scored relative to its membership to a particular class (i.e. degree of purity relative to a chemical component). Higher scores indicate more similarity to the pure component spectra. While these scores are not indicative of the absolute concentration of a chemical component, the relative abundance between the components is maintained, and can be calculated. If all sample components are accounted for, the scores for each component can be normalized to unity, and a statistical assessment of the relative abundance of the components made. [Pg.268]

Is there a clear description of what source data will be recorded directly into the CRF and what will be recorded in the medical records Normally, the protocol identification number, the date of consent, the date of commencement of the study, the visit dates, the start and finish dates of the administration of study drug and/or treatment, concurrent medication, adverse events and... [Pg.244]

What is clear without the further aid of statistics is that the methanol concentration is the most important factor. Equally, it is clear that the citric acid concentration is not significant nor are three of the four interactions. Are the methanol concentration main effect and/or the interaction between the methanol and citric acid concentrations significant One way forward is to plot the data from Table 6 on normal probability paper. If all these data are insignificant then they will lie on a straight line. If values are observed that are a long way off the line it is likely that the effects or interactions are significant. [Pg.32]

The present chapter deals first with all the preliminary steps which must be taken to obtain suitable data for structure determination (whether by direct or indirect methods)—the measurement of the intensities of diffracted beams, and the application of the corrections necessary to isolate the factors due solely to the crystal structure from those associated with camera conditions. It then goes on to deal with the effect of atomic arrangement on the intensities of diffracted beams, the procedure in deducing the general arrangement, and finally the methods of determining actual atomic coordinates by trial. It follows from what has been said that, as soon as atomic positions have been found to a sufficient degree of approximation to settle the phases of the diffracted beams, then the direct method can be used this, in fact, is the normal procedure in the determination of costal structures. [Pg.206]


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