scholarly journals Evaluation of saturated and aromatic hydrocarbons oil-oil maturity correlation parameters (SE Pannonian Basin, Serbia)

2007 ◽  
Vol 72 (12) ◽  
pp. 1237-1254 ◽  
Author(s):  
Ksenija Stojanovic ◽  
Branimir Jovancicevic ◽  
Dragomir Vitorovic ◽  
Yulia Golovko ◽  
Galina Pevneva ◽  
...  
Keyword(s):  
Cluster Analysis ◽  
Pannonian Basin ◽  
Oil Field ◽  
Crude Oils ◽  
Methyl Group ◽  
Cluster Analyses ◽  
Saturated And Aromatic Hydrocarbons ◽  
Correlation Parameters ◽  
Ward Method ◽  
Maturity Parameters

Twenty three crude oils from the Serbian part of the Pannonian Basin (14 from the Vojvodina Province and 9 from the Drmno Depression) were investigated, aimed at an evaluation of oil-oil maturity correlation parameters based on the distribution and abundance of saturated biomarkers and alkylarene constituents. Factor and cluster analyses were used for this purpose. Factor analyses using varimax rotation were first run separately, i.e., of maturity parameters based on the abundance of (a) n-alkanes and isoprenoids, (b) steranes and triterpanes, (c) alkylnaphthalenes, and (d) alkylphenanthrenes. These analyses yielded 9 important "maturity factors". Eight of them, showing higher than 30 % of variance, were further involved in another factor analysis, as well as in cluster analysis using the Ward method. In this way, all maturity parameters based on saturated biomarkers and alkylarenes were evaluated and ranged, considering the fact that the observed factors represented their linear combinations. The results showed that in the correlation of crude oils from the Serbian part of the Pannonian Basin, the most important were maturity parameters based on isomerization reactions involving one methyl group in thermodynamically less stable ?-methylnaphthalenes, ethylnaphthalenes, dimethylnaphthalenes and methylphenanthrenes, and their change into more stable isomers with the methyl group in the ?-position in the aromatic ring. Processes constituting high loadings factor 2 and factor 3 parameters were also defined. Hierarchy between the "factors" and parameters were controlled, and approved, by cluster analysis using the Ward method. Finally, the investigated crude oils were correlated by factor and cluster analyses, using all the important "maturity factors". Differences in maturity were observed between the Vojvodina and Drmno Depression crude oils, as well as between oils originating from South Banat, North Banat and the Velebit oil field (Vojvodina locality).

scholarly journals Multivariate statistical methods applied to interpretation of saturated biomarkers (Velebit oil field, se Pannonian basin, Serbia)

2006 ◽  
Vol 71 (7) ◽  
pp. 745-769 ◽  
Author(s):  
Tatjana Solevic ◽  
Ksenija Stojanovic ◽  
Branimir Jovancicevic ◽  
Gorica Mandic ◽  
Jan Schwarzbauer ◽  
...  
Keyword(s):  
Discriminant Analysis ◽  
Pannonian Basin ◽  
Oil Field ◽  
Gas Chromatography Mass Spectrometry ◽  
Thermal Maturity ◽  
Multivariate Statistical Methods ◽  
Multivariate Statistical ◽  
Correlation Studies ◽  
Discriminant Analyses ◽  
Ward Method

Twenty-five crude oils originating from the Velebit oil field (SE Pannonian Basin), the most important oil field in Serbia, were investigated. Saturated biomarkers (n-alkanes, isoprenoids, steranes and triterpanes) were analyzed by gas chromatography-mass spectrometry (GC-MS). Based on the distribution and abundance of these compounds, a large number of source and maturation parameters were calculated, particularly those most often used in correlation studies of oils. The examined samples were classified according to their origin and level of thermal maturity using factor, cluster and discriminant analyses. According to the source and maturation parameters, combined factor and cluster analyses using the Ward method enabled the categorization of the investigated oils into three groups. The cluster Ward analysis was shown to be of greater susceptibility and reliability. However, in addition to the two aforementioned methods, K-Means cluster analysis and discriminant analysis were shown to be necessary for a more precise and detailed categorization in the case of a large number of samples in one group. Consequently, it was concluded that factor and cluster K-Means and Ward analyses can generally be used for the interpretation of saturated biomarkers in correlation studies of oils, but the observed results have to be checked, i.e., confirmed by discriminant analysis.

Humor Style Clusters: Exploring Managerial Humor

2015 ◽  
Vol 55 (4) ◽  
pp. 443-454 ◽  
Author(s):  
Thomas Rhys Evans ◽  
Gail Steptoe-Warren
Keyword(s):  
Job Satisfaction ◽  
Cluster Analysis ◽  
Holistic View ◽  
Cluster Analyses ◽  
Significant Pattern ◽  
Humor Style

The current study is the first to explore the relationships between managerial humor and workplace facets using cluster analysis. Two-hundred and two employed adults rated their managers’ humor and workplace facets online. K-means cluster analyses identified three managerial humor clusters, mostly replicating those found in the existing literature. A significant pattern of differences in stress, communication, creativity, perceptions of leader power, and job satisfaction were found between the clusters. Findings suggest negative humor use is most likely to be damaging to organizations when not used alongside positive humor types, and it is not merely the frequency with which a manager uses an individual humor type, but the holistic view of their humor, which is of importance in gauging valence of organizational facets. Using cluster analysis was beneficial in challenging assumptions from the existing literature, further contextualizing our understanding of humor and reinforcing the importance of humor use in the workplace.

scholarly journals Genetic divergence among Nellore breed herds raised in the South Region of Brazil

2013 ◽  
Vol 43 (5) ◽  
pp. 878-883
Author(s):  
Jader Silva Lopes ◽  
Paulo Roberto Nogara Rorato ◽  
Tomás Weber ◽  
Ronyere Olegário de Araújo ◽  
Dionéia Magda Everling ◽  
...  
Keyword(s):  
Cluster Analysis ◽  
Genetic Divergence ◽  
Rio Grande ◽  
Southern Region ◽  
Rio Grande Do Sul ◽  
The South ◽  
Santa Catarina ◽  
Weaning Weight ◽  
Breeding Values ◽  
Ward Method

The objective of this study was to evaluate the genetic divergence among Nellore breed animals raised in 45 farms in the Southern Region of Brazil. The characteristic studied was weaning weight adjusted to 205 days of life (P205), from 10,874 animals sired by 425 bulls and 7,629 cows, collected between 1976 and 2001, and distributed in the states of Rio Grande do Sul (1,499), Santa Catarina (2,332) and Paraná (7,043). The animals were distributed by cluster analysis in eight genetic divergent groups, enabling this technique to be applied to organize the matings in order to obtain heterotic effect. The herd/farm groups were formed through the hierarchical Ward method, using the direct (VGD) and maternal (VGM) breeding values predicted by the REML method. The VGD of the animal accounted for 90% of the differences among herds, and the remaining 10% was attributed to differences in the VGM. On average, the P205 for the animals from inter-group mating was 1.4kg higher than those from intra-group mating, representing 2.4% of heterosis.

scholarly journals Determinants of milk production in FADN dairy farms in the regions of the European Union with predominance of intensive production in 2011

Management ◽  
2016 ◽  
Vol 20 (2) ◽  
pp. 473-486
Author(s):  
Marta Guth
Keyword(s):  
European Union ◽  
Cluster Analysis ◽  
Factor Analysis ◽  
Milk Production ◽  
Dairy Farms ◽  
The European Union ◽  
Intensive Production ◽  
Ward Method

Summary The main aim of the considerations was to determine the factors determining the variability of milk production in selected macroregions of the European Union. The regions were selected on the basis of the analysis of the diversity of dairy farms FADN in the regions of the European Union, which was determined by the agglomeration cluster analysis using Ward method. In order to highlight the determinants of production there was factor analysis made. On the basis of the results of factor analysis there were factors that have a decisive impact on milk production in dairy farms from areas with a predominance of intensive production identified, and there was a possibility to find out which macro-regions of the European Union reached a relatively best and worst performance in terms of the distinguished factors.

scholarly journals Classical Biomarker and Quantitative Extended Diamondoid Analysis Fingerprints for Crude Oils from Deepwater Developments in Block 17, Lower Congo Basin, Angola

2020 ◽  
Vol 17 (19) ◽  
pp. 7204
Author(s):  
Carlos Boente ◽  
Gonzalo Márquez ◽  
Patricia Marín ◽  
Emilio Romero ◽  
Cristina Rodrigues ◽  
...  
Keyword(s):  
Cluster Analysis ◽  
Organic Geochemistry ◽  
Hierarchical Cluster ◽  
Molecular Data ◽  
Congo Basin ◽  
Hydrocarbon Generation ◽  
Thermal Maturity ◽  
Maturity Level ◽  
Oil Type ◽  
Maturity Parameters

The organic geochemistry of six oil samples from the offshore Block 17 (Lower Congo Basin, northwestern Angola) was studied by a combination of classical biomarker and extended diamondoid analyses to elucidate source rock facies, the extent of biodegradation, and thermal maturity. Based on molecular data, oils are interpreted as depicting a mixture of two pulses of hydrocarbon generation probably from the Bucomazi and Malembo formations. Geochemical results also gave evidence of mixing of a lacustrine siliciclastic-sourced oil charge and a second more terrestrially derived oil type in the samples analyzed. A single genetic oil family was identified through hierarchical cluster analysis; however, two groups of oils were identified on the basis of their biodegradation levels using the Peters/Moldowan scale. Lower and upper Malembo oils have a slight depletion and a notable absence of n-alkanes, suggesting PM levels of 1 and 2, respectively. Most molecular maturity parameters of the oil samples suggest a maturity level equivalent to the onset of the peak of the oil generative window.

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