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Mathematical Fundamentals

ARIMA connects both autoregressive and moving average models and includes integrating effects, e.g. trends or seasonal effects. [Pg.234]

First an ARMA (autoregressive moving average) model will be explained without taking into account trends and seasonal effects in order to get a better understanding of the method. [Pg.234]

The first element of an ARMA process is the autoregression (AR process) it can be described as  [Pg.234]

6-40 refers to the time series as a linear combination of one or more previous [Pg.234]

For more effective notation it is necessary to introduce the backshift operator B  [Pg.234]


It is obvious that this conclusion is wrong Dimensional analysis is a method based on logical and mathematical fundamentals (2,6). If relevant parameters cannot be listed because they are unknown, one cannot blame the method. The only solution is to perform the model measurements with the same material system and to change the model scales. [Pg.16]

Until recently mathematical methods of time series analysis in the environmental sciences have only been used quite rarely the methods have mostly been applied in economic science. Consequently, the mathematical fundamentals of time series analysis are mainly described in textbooks and papers dealing with statistics and econometrics [FORSTER and RONZ, 1979 COX, 1981 SCHLITTGEN and STREITBERG, 1989 CHATFIELD, 1989 BROCKWELL and DAVIS, 1987 BOX and JENKINS, 1976 FOMBYet al., 1984 METZLER and NICKEL, 1986 PANDIT and WU, 1990], This section explains the basic methods of time series analysis and their applicability in environmental analysis. [Pg.205]

When applying multivariate autocorrelation analysis to this multivariate problem (for mathematical fundamentals see Section 6.6.3) two questions should be answered ... [Pg.276]

For the characterization of the selected test area it is necessary to investigate whether there is significant variation of heavy metal levels within this area. Univariate analysis of variance is used analogously to homogeneity characterization of solids [DANZER and MARX, 1979]. Since potential interactions of the effects between rows (horizontal lines) and columns (vertical lines in the raster screen) are unimportant to the problem of local inhomogeneity as a whole, the model with fixed effects is used for the two-way classification with simple filling. The basic equation of the model, the mathematical fundamentals of which are formulated, e.g., in [WEBER, 1986 LOHSE et al., 1986] (see also Sections 2.3 and 3.3.9), is ... [Pg.320]

The data matrix is subjected to hierarchical agglomerative cluster analysis (CA for the mathematical fundamentals see Section 5.3 further presentation of the algorithms is given by [HENRION et al., 1987]) in order to find out whether territorial structures with different multivariate patterns of heavy metals exist within the test area. [Pg.321]

The result from cluster analysis presented in Fig. 9-2 is subjected to MVDA (for mathematical fundamentals see Section 5.6 or [AHRENS and LAUTER, 1981]). The principle of MVDA is the separation of predicted classes of objects (sampling points). In simultaneous consideration of all the features observed (heavy metal content), the variance of the discriminant functions is maximized between the classes and minimized within them. The classification of new objects into a priori classes or the reclassification of the learning data set is carried out using the values of the discriminant function. These values represent linear combinations of the optimum separation set of the original features. The result of the reclassification is presented as follows ... [Pg.323]

The computation of the multivariate autocorrelation function (MACF) is useful if the simultaneous consideration of all measured variables and their interactions is of interest. The mathematical fundamentals of multivariate correlation analysis are described in detail in Section 6.6.3. The computed multivariate autocorrelation function Rxx according to Eqs. 6-30-6-37 is demonstrated in Fig. 9-6. The periodically encountered... [Pg.327]

The principle of multivariate analysis of variance and discriminant analysis (MVDA) consists in testing the differences between a priori classes (MANOVA) and their maximum separation by modeling (MDA). The variance between the classes will be maximized and the variance within the classes will be minimized by simultaneous consideration of all observed features. The classification of new objects into the a priori classes, i.e. the reclassification of the learning data set of the objects, takes place according to the values of discriminant functions. These discriminant functions are linear combinations of the optimum set of the original features for class separation. The mathematical fundamentals of the MVDA are explained in Section 5.6. [Pg.332]

The purpose of application of factor analysis (FA) is the characterization of complex changes of all observed features in partial systems of the environment by determination of summarized factors which are more comprehensive and causally explicable. The method extracts the essential information from a data set. The exclusive consideration of common factors in the reduced factor analytical solution seems to be particularly promising for the analytical process. The specific variances of the observed features will be separated from the reduced factor analytical results by means of the estimation of the communalities. They do not falsify the influence of the main pollution sources (see also Tab. 7-2). The mathematical fundamentals of FA are explained in detail in Section 5.4.3 (see also [MALINOWSKI, 1991 WEBER, 1986]). [Pg.335]

The influence of water components on the flame photometric determination of potassium and sodium can be detected by factorial experiments. By application of multifactorial plans according to PLACKETT and BURMAN the qualitative determination of the influence of various variables is possible with relatively few experiments [SCHEFFLER, 1986]. For mathematical fundamentals see Chapter 3. [Pg.364]

The book consists of two main parts. The first part has a more methodological character, it is technique-oriented. In the sections of this part mathematical fundamentals of important newer chemometric methods are comprehensively represented and discussed, and illustrated by typical and environmental analytical examples which are easy to understand. The second part, which has been written in a more problem-orientated format, focuses on case studies from the field of environmental analysis. The discussed examples of the investigation of the most important environmental compartments, such as the atmosphere, hydrosphere, and pedosphere, demonstrate both the power and the limitations of chemometric methods applied to real-world studies. [Pg.390]

A detailed, very advanced introduction to basic Hartree-Fock, Cl and MP theory. Well-known as a rigorous introduction to the mathematical fundamentals. [Pg.575]

P.M. Smith, W.R. Welch, S.M. Graham, H.R. Chughtai, P. Schissel Mathematical fundamentals of polymers photodestruction. 2. Study of PETP and polyvinylfluoride by the method of their infrared spectroscopy with Fourier converter// Sol. Energy Mater (1989), No 1-2, 111-120 (in Russian). [Pg.172]

The mathematical fundaments for possibilistic fuzzy clustering of fuzzy rules were presented. The P-FCAFR algorithm was used to organize the rules of the fuzzy model of the liquid level inside the Pilot Plant Reactor in the HPS structure. The partition matrix can be interpreted as containing the values of the relevance of the sets of rules in each cluster. This approach is currently showing its potential for modelling and identification tasks, particularly in the fault detection and compensation field. [Pg.904]

A well-defined mathematical fundament for calculating with probabilities was established by Kolmogorov. E.g. the first axiom postulated that every random event A has a probability P(A), where ... [Pg.1934]

It is hoped that the more advanced reader will also find this book valuable as a review and summary of the literature on the subject. Of necessity, compromises have been made between depth, breadth of coverage, and reasonable size. Many of the subjects such as mathematical fundamentals, statistical and error analysis, and a number of topics on electrochemical kinetics and the method theory have been exceptionally well covered in the previous manuscripts dedicated to the impedance spectroscopy. Similarly the book has not been able to accommodate discussions on many techniques that are useful but not widely practiced. While certainly not nearly covering the whole breadth of the impedance analysis universe, the manuscript attempts to provide both a convenient source of EK theory and applications, as well as illustrations of applications in areas possibly u amiliar to the reader. The approach is first to review the fundamentals of electrochemical and material transport processes as they are related to the material properties analysis by impedance / modulus / dielectric spectroscopy (Chapter 1), discuss the data representation (Chapter 2) and modeling (Chapter 3) with relevant examples (Chapter 4). Chapter 5 discusses separate components of the impedance circuit, and Chapters 6 and 7 present several typical examples of combining these components into practically encountered complex distributed systems. Chapter 8 is dedicated to the EIS equipment and experimental design. Chapters 9 through 12... [Pg.1]


See other pages where Mathematical Fundamentals is mentioned: [Pg.166]    [Pg.471]    [Pg.29]    [Pg.114]    [Pg.234]    [Pg.258]    [Pg.264]    [Pg.323]    [Pg.331]    [Pg.342]    [Pg.140]    [Pg.187]    [Pg.260]    [Pg.53]    [Pg.411]    [Pg.19]    [Pg.183]   


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