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.1023/A:1011976615750. 13. K. H. Esbensen, D. Guyot, F. Westad and L. P. Houmoller: Multivariate data analysis: in practice: an introduction to multivariate data analysis and experimental design, CAMO AS Publications, Oslo 2004, pp. 598. 14. P. Sansdrap and A. J. Moes, Influence of manufacturing parameters on the size characteristics and the release profiles of nifedipine from poly (DL-lactide-co-glycolide) microspheres, Int. J. Pharm. 98 (1993) 157-164; DOI: 10.1016/0378-5173(93)90052-H. 15. M. Hamoudeh and F. Hatem, Preparation, characterization and surface study of

Abstract

The determination of the sensorial quality of wines is of great interest for wine consumers and producers since it declares the quality in most of the cases. The sensorial assays carried out by a group of experts are time-consuming and expensive especially when dealing with large batches of wines. Therefore, an attempt was made to assess the possibility of estimating the wine sensorial quality with using routinely measured chemical descriptors as predictors. For this purpose, 131 Slovenian red wine samples of different varieties and years of production were analysed and correlation and principal component analysis were applied to find inter-relations between the studied oenological descriptors. The method of artificial neural networks (ANNs) was utilised as the prediction tool for estimating overall sensorial quality of red wines. Each model was rigorously validated and sensitivity analysis was applied as a method for selecting the most important predictors. Consequently, acceptable results were obtained, when data representing only one year of production were included in the analysis. In this case, the coefficient of determination (R2) associated with training data was 0.95 and that for validation data was 0.90. When estimating sensorial quality in categorical form, 94 % and 85 % of correctly classified samples were achieved for training and validation subset, respectively.

Abstract

Riparian vegetation reflects the current conditions and the dynamics of streams. The floodplain vegetation along the watercourse of the Morávka River was subject to study in this project. In some reaches, the river has the natural character of an anabranching gravel-bed stream; in contrast, other Morávka R. reaches are incised into the bedrock. These cases were used to assess potential changes in vegetation conditions as evidence of negative processes taking place in the gravel-bed streams of the Beskydy Mts. The results demonstrate a higher biodiversity in the floodplain along the anabranching river channel. In contrast, the floodplain along the incised river channel shows low biodiversity values. Redundancy analysis was used to determine the relationships between plant species composition, distance from the main channel and relative elevation from the mean water level of the main channel. In addition, the results show a higher degree of change in plant species composition on the floodplain along the incised river channel. The analysis of floodplain groundwater fluctuations shows a decreasing trend in the annual maximum groundwater level.

statystycznej w badaniach rynku. Warszawa: Wydawnictwo SGGW. Grabiński, T. (1985). Metody określania charakteru zmiennych w wielowymiarowej analizie porównawczej. Zeszyty Naukowe Akademii Ekonomicznej w Krakowie, nr 213, 35-63. Hair, J.F. jr, Anderson, R.E., Black, W.C. & Tatham, R.L. (1998). Multivariate data analysis 5th ed. New Jersey: Prentice-Hall International. Hellwig, Z. (1981). Wielowymiarowa analiza porównawcza i jej zastosowanie w badaniach wielocechowych obiektów gospodarczych. In: Ed. W. Welfe. Metody i modele ekonomiczno- matematyczne w doskonaleniu zarządzania

Abstract

Total luminescence and synchronous scanning fluorescence spectroscopic techniques were investigated for differentiating brandies from mixed wine spirits. The studies were performed on 16 brandies from 3 different producers and 30 mixed wine spirits from 5 different producers. Differentiation between samples was accomplished by multivariate data analysis methods (principal component analysis, hierarchical cluster analysis, and linear discriminant analysis). Correct classification was obtained using emission spectra (400-650 nm) recorded at excitation wavelength 390 nm, excitation spectra (225-460 nm) obtained at emission wavelength 470 nm and synchronous fluorescence spectra (200-700 nm) collected at wavelength interval 80 nm. These results indicate that right-angle fluorescence spectroscopy offers a promising approach for the authentication of brandies as neither sample preparation nor special qualification of the personnel are required, and data acquisition and analysis are relatively simple when compared to front-face technique.

Abstract

Samples of commercially available Romanian wines were analyzed in order to determine total phenols content and the antioxidant activity. The content of total phenolics in the extracts was determined according to the Folin-Ciocalteu method and calculated as gallic acid equivalents (mg GAE/100g). Antiradical activities of the extracts were evaluated by a micro assay using 1, 1¢-diphenyl-2-picrylhydrazyl spectrophotometric method. Wine characteristics measurements were examined by multivariate data analysis, using principal component analysis (PCA). Total polyphenol content was correlated to the antioxidant activity of the studied wine samples. The values of the inhibition power of free radical, PI%, are ranging between 1.68 for white wine and 0.95 for red wine (“Bull blood” bottled by Tohani winery, Prahova, Romania).

Abstract

The cadastral district of Horný Tisovník represents a traditionally managed Carpathian mountain agricultural landscape with extensive terraces. It was historically governed by two counties with different feudal economic systems - agricultural and industrial. This paper aims to enrich traditional methods in environmental history. We applied geospatial statistics and multivariate data analysis for the assessment of environmental factors influencing the distribution of agricultural terraces. Using linear models, the hypothesis was tested that the terrace distribution is functionally related to selected factors (affiliation to the historic counties; average altitude and slope; distance from water, buildings and settlements; units of natural potential vegetation; and current land use). Significantly greater amounts of terraces were located in the agricultural county compared to the industrial county. A principal component analysis showed the coincidence between the current agricultural land use and higher concentrations of terraces occurring in lower altitudes, closer to settlements and buildings, and within the unit of Carpathian oak-hornbeam forests. These findings regarding the most significant factors influencing the distribution of terraces are used in proposals for incentives to improve the management of the traditional agricultural landscape.

Abstract

Wildfire is regarded as important environmental factor determining the vegetation of the Earth. We analyzed 11 plots at different types of forest affected by fire at the southern boundary of the taiga zone. These differ in structure of the forest stand and herb-shrub layer. Investigated factors included edaphic (moisture, pH, nitrogen) and climatic (light, temperature, continentality) characteristics. Also, projective cover of Epilobium angustifolium L. and undergrowth of secondary growth trees (including forest stand survived after fire influence) were studied. Multivariate data analysis revealed that the rate and character of the vegetation recovery was depended on the ratio of environmental factors and on the species composition of herb-shrub layer. No significant differences were found in Ellenberg’s indicator values between different years of study. All tested forest habitats were distinguished into three main groups: Group I includes broadleaf forests with the forest stand survived after fire influence, Group II includes spruce and birch forests deprived the forest stand due to fire impact, Group III includes more or less dry pine-dominated forests with the forest stand gradually died after fire influence. Two marshy plots have prerequisites to their allocation to a separate group close to the oligotrophic bog forests.

., Iwasiewicz A., Paszek Z., Sikorski A. Metody statystyczne dla chemików, PWN, Warszawa, 1992. Draper N. R., Smith H. Applied regression analysis, John Wiley & Sons Inc, 1998. Jobson J. D. Applied multivariate data analysis, Springer-Verlag, New York, 1991.

. (2007). TMVA – Toolkit for Multivariate Data Analysis. PoS ACAT 040. arXiv:physics/070303. Hoecker A. Speckmayer P. Stelzer J. Therhaag J. Von Toerne E. Voss H. 2007 TMVA – Toolkit for Multivariate Data Analysis PoS ACAT 040 arXiv:physics/070303 3. Brun, R., & Rademakers, F. (1997). ROOT – An Object Oriented Data Analysis Framework. Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. 389 (1/2), 81–86. Brun R. Rademakers F. 1997 ROOT – An Object Oriented Data Analysis Framework Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom