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JERZY STRASZKO, URSZULA GABRIEL, ANNA POŚWITAJŁO Processes and phenomena are usually described by complex processes or phenomena (air contamination structural methods. Models are built on the basis of theory. propagation belongs to this type of processes) it is usually Experimental data in this case serve for verification of difficult to build sufficiently precise theory. It should be theory and determination of coefficients of the equations added that obtainment of data for calculations with use of describing process or phenomenon. This method is time structural models is expensive and sometimes also consuming and requires significant expenditures. Other, impossible. instuctural methods instead, consist in deduction on phenomenon directly on the basis of measurements results. There are known fundamentals of this depiction of the problem and implementations in form of computer software. These methods are classified as artificial computational intelligence. They are applied in various This types of problems occur in many disciplines. For description of these phenomena instructural analysis systems, using directly the experimental data, have been elaborated [19, 20]. There exist good bases of these methods and their applications in the form of computer software. These methods are classified as artificial branches. In this work the methods are used for analysis of computing intelligence and they found many applications. the results of air–monitoring stations measurements in They are still developed. Cracow region. Conventional (traditional) statistical methods are General part insufficient nowadays. The aim of traditional data analysis In air quality assessment codified systems oblige. They use is most often hypothesis verification or theory verification. However in practice it is in question to obtain as quickly as mathematical methods of modeling of atmospheric possible an easy hint necessary for making decisions. transport and methods of direct assessment based on the Methods of data mining provide this kind of information. measurements results. In theory of contaminants New methods do not eliminate the old proven systems. propagation structural models of Gauss, Euler or Lagrange They require however their more effective use. are used. They were described in the books [1–3], monographs [4–7], doctoral thesises [8–10] and <strong>numer</strong>ous publications [11–16]. Applications of these models are also codified in the form of recommended computer Irrespectively of adopted method of analysis, adequate quality of data is the key factor influencing the results, and so the quality of the build model. Before the calculations software. Analysis of imission measurement results in Cracow region by instructural methods Keywords: air monitoring, Cracow region, results analysis, instructural methods; the type of model, for instance deterministic equation or neural network has to be selected, and the results have to be In case of analysis of imission measurements results other prepared so that they could be useful i.e. preprocessing is issues appear. They refer especially to determination of performed. Then analysis of data correctness and probabilistic characteristics of measured values. First unambiguousity is carried out. Gathered data cannot works in this field were published by Larsen [17, 18]. He contain any failures. Occurrence of untypical observations used the one–dimensional distributions and stated that the needs to be investigated too. If gathered data are lognormal distribution was most often fulfilled by the incomplete, the missing values can be filled up, for experimental data. Many publications later on devoted example by replacing them with average, median or attention to this issue. removing the cases in which failure occurs. The values recorded at monitoring stations are random Second stage consists in model building and its evaluation. variables. Measured in time they determine time series. In Different models, for example different neural networks theories applied to this problem deterministic models, and are tested. The best model is selected, usually basing on more generally structural models, predominate. In case of statistical evaluation. Applying the built models usually two kinds of tasks are solved: more direct one, namely prediction and more general consisting in knowledge Prof. dr hab. inż. J. Straszko, dr inż. U. Gabriel, mgr inż. A. Poświtajło – Instytut discovering. Prediction refers to the situation when we Inżynierii Materiałowej, Politechnika Szczecińska 132 Problemy Ekologii, vol. 14, nr 3, maj-czerwiec 2010
have complete data from the past, and we currently want to neural networks method the describing and described predict the values on the basis of incomplete data we have. variables have to be defined. Time, wind speed, wind In this way of predicting regression and classification are direction and temperature belong to describing variables. used. A specific case of regression is prediction of future Contaminants concentrations should be classified in values of time series. As mentioned before the values of general to described variables. variables measured at air monitoring stations determine the time series. While describing contaminants concentrations measured at monitoring stations usually we do not have important Knowledge discovery is the discerning description of data, information such as number of emitters located in the indicating the structures, dependencies and information examined area, their technical characteristics and the hidden in them. This was the main aim of this work. The quantity of emission, which are the basis of structural results obtained by artificial computing intelligence can be models of atmospheric transport of contaminants. useful as an essential complement of currently performed analyses during air quality assessment. During the construction of the way of analysis in this work the redundancy principle was used. It consists in that some Experimental data of the measured values can complete the missing information. For example the temperature is connected The calculations were based on the results of with fuel combustion for heating purposes. Hence this measurements performed according to the standing could complete the results concerning the contaminants regulations in the period of September 2007 – April 2008 at emission from these processes. It should be added that the automatic air monitoring stations in Cracow region some contaminants react in air. Than their concentrations [21]. In figure 1 locations of all the stations, including the interdependency is natural. planned ones, are presented. Statistica Neural Networks computer software was used In figure 2 distributions of 1–hour concentrations of for calculations [23-26]. MLP (Multilayer Perceptron), contaminants and distributions of meteorological RBF (Radial Basis Function) and GRNN (Generalised parameters registered at Nowa Huta station are presented Regression Neural Networks) were tested. Good accuracy as example. was usually obtained for GRNN networks. Therefore these networks were used the most often. According to evaluations of Voivodeship Environmental Protection Inspectorate in Cracow, in year 2008 in Lesser The way of calculations performing has been shown at the Poland Voivodeship exceedances of permissible pollution example of dependencies of 1-hour contaminants target levels and permissible pollution levels extended by concentrations registered at Nowa Huta station. In figure 3 tolerance margin for the following substances occurred: architecture of the built neural network is presented. particulate matter PM10 – average concentration per calendar year, particulate matter PM10 – 24–hour concentration, nitrogen dioxide – average concentration per calendar year and annual average concentration. The first number stands for the number of describing variables, and the second one for the number of hidden neurons. Statistical evaluation of the network is given in table 1. This work does not concern the assessment of air contamination according to the standing procedures. The In figure 4 concentration values of NOx calculated by neural network and determined experimentally are aim was the analysis of the data by artificial computational compared. intelligence methods indicating the structures, dependencies and regularities hidden in them. The first The satisfactory accuracy was obtained. The built neural stage was determination of probabilistic characteristics of model could have been used in further calculations. The measured values by traditional statistical methods. Known first stage was estimation of parametric sensitivity. The one–dimensional distributions were tested [2]. It was results are listed in table 2. demonstrated, that the lognormal distribution was most Table 1. Statistical evaluation of GRNN 9/2472 network often fulfilled by the experimental data registered at monitoring stations. Analysis of functional dependencies Investigations of interdependencies between registered variables, i.e. knowledge discovering indicating the structures and regularities hidden in data, were called the functional analysis. To perform the analysis by artificial Problemy Ekologii, vol. 14, nr 3, maj-czerwiec 2010 133
Page 1 and 2: ISSN 1427-3381 2010 3 Aktualna punk
Page 3 and 4: V 3 (81) maj - czerwiec 2010 dr n.
Page 5 and 6: czynniki w ostatnim półwieczu zmi
Page 7 and 8: 2) sprawcą przestępstwa jest osob
Page 9 and 10: Dodatkową sankcją obligatoryjną
Page 11 and 12: Rys.2. Koło strategii ekoprojektow
Page 13 and 14: Policy). Celem podejścia określon
Page 15 and 16: JOANNA GLIWICZ Nieprzewidywane skut
Page 17 and 18: w skali wieloletniej można uznać
Page 19 and 20: Rys. 4. Spadek zagęszczenia w popu
Page 21 and 22: został wprowadzony w celu osiągni
Page 23 and 24: W Śląskim Ogrodzie Botanicznym pr
Page 25: Rys. 4. fot.: M. Jańczak. Jabłoni
Page 29: Conclusions [11] Straszko J., Paulo
Page 34 and 35: Rys. 1. Mapa zlewni rzeki Mała Pan
Page 36 and 37: niki korelacji (r = -0,54)0,32) dla
Page 38 and 39: PIOTR P. MAŁECKI Tendencje zmian w
Page 40 and 41: (tab. 1). Są one obliczone tylko d
Page 42 and 43: Rys. 6. Udział poddanych odzyskowi
Page 44 and 45: ozwoju obecnych i przyszłych pokol
Page 46 and 47: 152 Przejściowy raport z wdrażani
Page 48 and 49: Polacy uczą międzynarodowych eksp
Page 50 and 51: TERESA SADOŃ-OSOWIECKA Krajoznawst
Page 52 and 53: staje się sytuacja z baśni „Św
Page 54 and 55: (wywiady, obserwacje, studia litera
Page 56: Fot.: M. Jańczak. Owocująca jabł

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