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EN
The paper presents results of multivariate analysis of variations of radon concentrations in the shallow underground laboratory and a family house, depending on meteorological variables only. All available multivariate classifi cation and regression methods, developed for data analysis in high-energy physics and implemented in the toolkit for multivariate analysis (TMVA) software package in ROOT, are used in the analysis. The result of multivariate regression analysis is a mapped functional behaviour of variations of radon concentration depending on meteorological variables only, which can be used for the evaluation of radon concentration, as well as to help with modelling of variation of radon concentration. The results of analysis of the radon concentration variations in the underground laboratory and real indoor environment, using multivariate methods, demonstrated the potential usefulness of these methods. Multivariate analysis showed that there is a potentially considerable prediction power of variations of indoor radon concentrations based on the knowledge of meteorological variables only. In addition, the online system using the resulting mapped functional behaviour for underground laboratory in the Institute of Physics Belgrade is implemented, and the resulting evaluation of radon concentrations are presented in this paper.
EN
The insurance internal market has existed since 1993 (enforced by the third life directive). Its’ main features are a common framework to allow insurers to operate throughout the EU and to establish and provide services freely. On the other hand, the legal framework was designed to protect customers, particularly individuals, where the safe delivery of promised benefits can be vital. One can observe that these frameworks do not guarantee that insurance markets develop in the same way. Insurers are more likely to set up their businesses in some countries than in others. There are also differences in: the number of policies, the amount of benefits and other indicators among European countries. The question is, whether we can talk about the internal market or rather a group of different national markets. Trying to answer this question, we have to take into account a set of variables that shows all the major aspects of integration. The main purpose of this study is evaluating the level of European markets integration by using multivariate statistical methods. We shall also compare results obtained owing to application of different methods and will try to explain similarities and differences between the obtained results.
PL
Jednolity rynek ubezpieczeń funkcjonuje we Wspólnocie Europejskiej od 1993 r. (od wprowadzenia dyrektywy trzeciej generacji w ubezpieczeniach na życie). Jego działanie oparte jest na trzech podstawowych zasadach tworzących Unię Europejską, swobody tworzenia podmiotów gospodarczych, swobody świadczenia usług oraz przepływu kapitału między krajami. Celem rynku wewnętrznego w dziedzinie ubezpieczeń jest zagwarantowanie wszystkim mieszkańcom Wspólnoty dostępu do możliwie najszerszej gamy wysokiej jakości produktów ubezpieczeniowych oferowanych przez zakłady ubezpieczeń z obszaru całej Wspólnoty. Ubezpieczyciele upoważnieni do działania w jakimkolwiek państwie członkowskim mogą prowadzić swoją działalność na terenie całej Wspólnoty i podlegają takim samym zasadom nadzoru. Gwarantowane dyrektywami jednakowe warunki rozwoju sektora ubezpieczeń nie znajdują pełnego odzwierciedlenia w regulacjach wewnętrznych państw członkowskich. Część z nich, Poprzez sprzyjające regulacje podatkowe i administracyjne, jest zdecydowanie częściej wybierana przez zakłady ubezpieczeń jako państwo siedziby. Pozostaje więc otwarte pytanie, czy europejski rynek ubezpieczeń jest organizmem jednolitym? Próba odpowiedzi na to pytanie wiąże się z oceną stopnia integracji rynków ubezpieczeniowych w Unii Europejskiej. Ocena taka nie może ograniczać się do analizy tylko jednego wskaźnika ekonomiczno-ubezpieczeniowego, gdyż zagadnienie integracji rynków ubezpieczeniowych, jak wskazano, jest zjawiskiem wieloaspektowym. W celu dokonania poprawnej oceny stopnia integracji rynków można posłużyć się metodami statystyki wielowymiarowej. Celem niniejszego artykułu jest określenie stopnia integracji rynków ubezpieczeniowych krajów Unii Europejskiej przy wykorzystaniu metod analizy wielowymiarowej. Równoległym celem jest porównanie wyników uzyskiwanych przy pomocy różnych metod statystyki wielowymiarowej i próba ich oceny.
EN
The involvement in various forms of non-work activities of persons aged 50 and over in Poland is discussed in this paper. The range of participation is compared to other European countries. The presented considerations indicate that the Polish generation 50+ is characterized by a very high level of inactivity, particularly in the field of volunteering, charity and clubs membership. On the other hand, the involvement in religious organizations is very high. Such factors as age, gender and state of health have a significant impact on the participation in certain activities. Crucial importance may be also assigned to the unfavorable financial situation.
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EN
Testing differences between multivariate populations is one of a crucial problems in statistical investigations. The most known – MANOVA tests being parametric ones need to fulfill the assumptions about the conformity with multivariate normal distribution. Very often these assumptions are practically unrealistic or the verification, especially for small number of observations is hard. This paper presents an approach, based on permutation tests (no needs of verification mentioned assumptions), where proposed test statistics base on the properties of eigenvectors. The investigations were carried out for simulated and real multivariate datasets, where the permutation tests were compared with variable-based and MANOVA test statistics.
PL
Testowanie różnic pomiędzy populacjami wielowymiarowymi jest jednym z kluczowych problemów w badaniach statystycznych. Najbardziej znane – testy MANOVA, jako parametryczne wymagają spełnienia założenia o zgodności z rozkładem normalnym wielowymiarowym. Bardzo często założenia te są praktycznie nierealne lub ich weryfikacja, szczególnie dla małej ilości obserwacji jest trudna. Artykuł ten przedstawia podejście, oparte o testy permutacyjne (co zwalnia z weryfikacji powyższych założeń), gdzie proponowane statystyki testowe oparte są o własności wektorów własnych. Badania zostały przeprowadzone dla symulowanych i rzeczywistych zestawów danych, gdzie testy permutacyjne zostały porównane z testami opartymi na analizie zmiennych i statystykach testowych w MANOVA.
EN
In many applications of the multivariate analyses of variance, the classic parametric solutions for testing hypotheses of equality in population means or multisample and multivariate location problems might not be suitable for various reasons. Multivariate multisample location problems lack a comparative study of the power behaviour of the most important combined permutation tests as the number of variables diverges. In particular, it is useful to know under which conditions each of the different tests is preferable in terms of power, how the power of each test increases when the number of variables under the alternative hypothesis diverges, and the power behaviour of each test as the function of the proportion of true alternative hypotheses. The purpose of this paper is to fill the gap in the literature about combined permutation tests, in particular for big data with a large number of variables. A Monte Carlo simulation study was carried out to investigate the power behaviour of the tests, and the application to a real case study was performed to show the utility of the method.
EN
The analysis of weak variations in the energetic particle flux, as detected by neutron or muon monitors, can often be considerably improved by analysing data from monitor networks and thereby exploiting the spatial coherence of the flux. We present a statistical framework for carrying out such an analysis and discuss its physical interpretation. Two other applications are also presented: filling data gaps and removing trends. This study focuses on the method and its various uses.
EN
Describing the environment with quantitative data is a new requirement in the environment related sciences which is the consequence of the developing computerbased methods. New requirements with new tools generated quick development in the measuring level: parameters turned to be measurable in several subjects. Landscape ecology as a young science has its own methods from the beginnings, but the quantified landscape geometry indices appeared only in the 1980s. Exploration of the landscape structure made necessary to elaborate those methods which were applicable to characterize the patches, corridors and the matrix of the landscapes. Nowadays we can find several landscape indices to quantify the geometry of landscape elements in patch and landscape level, but they are not used in the practice of the landscape management. It is shown in this paper that these landscape indices what novelty can mean in a sample area of Northern Hungary and what can be the practical side of their the usage. FRAGSTATS software was used to calculate landscape metrics. Principal component analysis was applied to reduce redundancy of indices and, based on the results, some of them was selected. Land use types and microregions were used as dependent variables in a discriminant function analysis. Both of them were identifiable with this method in several cases. Landscapes were clustered based on the characteristics of the landscape indices.
PL
Przedstawiono zróżnicowanie poziomu i kierunki rozwoju infrastruktury transportowej w nowych krajach członkowskich UE oraz w państwach aspirujących do tej organizacji. Rozważa się również tempo i kierunki transformacji badanego zjawiska. Zastosowanie metody statystycznej ma na celu dokonanie charakterystyki wielowymiarowego problemu poprzez utworzenie zmiennej agregowanej. Metodologia tworzenia tego miernika obejmuje proces normalizacji bazowych charakterystyk (unitaryzacja zerowana). Rezultatem badania jest dokonanie typologii badanych krajów ze względu na poziom rozwoju studiowanego problemu. Nastepnie wykonano prognozę kierunków rozwoju infrastruktury w poszczególnych krajach. Obejmuje ona oszacowanie czasowe wyrównywania dysproporcji rozwojowych.
EN
The paper presents the diversity of the transport infrastructure development in new EU members and countries aspiring to that organisation. Directions and the tempo of this phenomenon transformation are considered, as well. A statistical analysis is employed to characterise multivariate phenomenon by creation of an aggregate variable. The methodology of building up this measure encompasses normalisation process of diagnostic characteristics (zeroed unitarisation). The outcome of the research is a typology of countries according to the developmental level of an issue under investigation. Subsequently the research focuses on the prognosis of directions of the infrastructure transformation in individual countries. The forecast includes the time estimate of developmental disproportions equalization.
EN
The aim of this article is to identify diversity between the EU-15 and the New Members in their implementation of the Lisbon Strategy in the period 2000-2010. By analyzing a set of structural indicators, we aim to fill a gap in the literature: the lack of publications providing complex evaluation of the implementation of the Lisbon Strategy using measurable indicators. Given their suitability for international comparisons, we use two taxonomic methods: Ward’s cluster analy-sis and the synthetic variable method proposed by Hellwig. The results of our analyses confirm the hypothesis of a large gap between the EU-15 countries and the 12 New Members in the key areas of the Lisbon Strategy. According to rankings given by our taxonomic analyses, a high level of the indicators selected is confirmed only for the EU-15 countries and only three New Members belong to a group presenting the average level of these indicators. This study demonstrates a need for a significant intensification of the EU cohesion policy, which is one of the main tools for achieving the Lisbon Strategy goals.
EN
In this paper the relationship between temporal changes in the occurrence of water masses and Trichiuridae and Gempylidae larvae composition and distribution in the Southwest Atlantic ocean were analysed between 25° and 40° S. Ichthyoplankton was collected during the three expeditions of the Subtropical Convergence Project: Winter and Spring 1977, Autumn 1978 and Summer 1981, realized in the Southwest Atlantic waters. Oblique tows were conducted using a Hensen net with 250 ěm mesh size. Steep salinity and temperature gradient were found, where the river outflows from La Plata river (Argentina) and Patos Lagoon (Brazil) met the Tropical Water over the continental shelf between 32 and 36° S. We examined 524 Hensen-net samples that contained about 283 larvae from five species of Trichiuridae and Gempylidae. The most abundant and frequent specie were Trichiurus lepturus Linnaeus 1758 and Diplospinus multistriatus Maul 1948. The mesopelagics species D. multistriatus, Nealotus tripes Johnson 1865 and Lepidopus altifrons Parin&Collette, 1993 were associated with Tropical Water. The benthopelagic T. lepturus and the epipelagic Thyrsitops lepidopoides (Cuvier 1832) were associated mainly with Coastal Water and Subtropical Shelf Water.
EN
The purpose of this study was to show relationships among the levels of essential metals (zinc, iron, sodium, magnesium, calcium and potassium) and phenolic acids (caffeic, chlorogenic, ferulic, gallic, rosmarinic and syringic) in commercial herbs (lemon balm, thyme, rosemary, mint, sage and angelica) and spices (caraway, lovage, hyssop and oregano). In the herbs higher quantities of metals and phenolic compounds were found than in spices. All plants contained high levels of calcium, potassium and rosmarinic acid, but low levels of zinc and gallic acid. By using principal component and hierarchical cluster analyses several clusters were identified grouping samples originating from a plant of a particular botanical species. Multivariate analysis has also shown that the contents of phenolic acids had a stronger impact on the scattering of herbs and spices than the metals levels. Furthermore, statistically significant correlations were found between calcium and ferulic, gallic, rosmarinic and syringic acids as well as between zinc and sodium and caffeic acid. This suggests co-operate between these biologically active constituents in metabolic processes occurring in plants.
EN
This study used multivariate statistics including cluster analysis (CA) and principal component analysis (PCA) to evaluate the variability and key indicators causing changes in soil quality in Tram Chim National Park, Dong Thap province, Vietnam. Soil samples were collected in the dry season at the habitats of Ischaemum rugosum (CM), Panicum repens (CO), Nelumbo nucifera (LS), Eleocharis dulcis (NO), Oryza rufipogon (LM), Rice field (RL), Melaleuca cajuputi (T) in two layers: A (0–20 cm) and B (20–40 cm). The parameters of pH, total nitrogen (TN), total phosphorus (TP), total acidity (TA), organic matter (OM), total iron (Fe) and exchanged aluminum (Al3+) were used to assess soil quality. The results showed that soil pH was low in both A and B layers. Fe and Al were both high, and the concentrations of these metals in layer A were higher than those in layer B. The OM content was medium while the TN and TP levels were very low. Most of the soil quality indicators tended to decrease with the depth (except for TA). The results of CA analysis showed that there was almost no major change in soil quality between the two soil layers; however, the soil quality in rice field habitat was different from other habitats. The cause may be due to human impact in adding fertilizers/pesticides during farming practices. The PCA results showed at least five influencing factors, explaining 99.7% and 99.9% of soil quality variation in A and B layers. The Al3+, TA, OM, and TP parameters had the main influence on the soil quality of layer A. Meanwhile, the pH, Al3+, TA, TN, Fet indicators had influence on the soil quality of layer B. These indicators need to be future surveyed to assess the evolution of soil quality in the study area.
EN
During the research, 71 groundwater samples were collected over a 300 km2 area of Tirana-Fushe Kuqe alluvial aquifer extension (central-western Albania) and subsequently analyzed for 11 parameters (pH, K+, Na+, Ca2+, Mg2+, HCO3-, Cl-, SO42-, NO3-, TH and TDS). Both geochemical conventional (Piper and Chadha diagrams) methods of groundwater classification and multivariate statistical (principal components analysis – PCA and hierarchical cluster analysis – HCA) methods were applied to the dataset to evidence the geochemical processes controlling groundwater geochemistry evaluation through the aquifer. The conventional geochemical methods revealed four (G1–G4) hydrochemical groups where the dominant group is G2 the samples of which are from unconfined to semiconfined recharge zone and the majority of them have Ca-Mg-HCO3 groundwater. Group G3 includes the samples from the confined coastal aquifer having Na-Cl groundwater. Group G1 includes three groundwater samples of Ca-Mg-SO4 from the central part of the aquifer, while group G4, the samples of which are spatially located between G3 and G2 zones, has Na-HCO3 groundwater. The first four components of the PCA account for 85.35% of the total variance. Component PC1 is characterized by very high positive loadings of TH, Ca2+, and Mg2+, suggesting the importance of dissolution processes in the aquifer recharge zone. Component PC2 is characterized by very high positive loadings in Na+, K+, and Cl-and moderate to high loadings of TDS, revealing the involvement of seawater intrusion and diffusion from clay layers. On the basis of their variable loadings, the first two components are defined as the “hardness” and “salinity”, respectively. The HCA produced four geochemically distinct clusters, C1–C4. The samples of cluster C1 are from the coastal confined aquifer and their groundwater belongs to the Na-Cl type. The samples from cluster C2 are located in the south and east recharge areas and most of them have Ca–Mg–HCO3 groundwater, while the samples from cluster C3, which are located in the northeastern recharge zone, have Mg-Ca–HCO3 groundwater. Finally, cluster C4 includes two groundwater subgroups having Na-Cl-HCO3 and Na-Mg-Cl-HCO3 groundwater in the vicinity of cluster C1 as well as Na-HCO3-Cl and Na-Mg-HCO3-Cl groundwater next to cluster C2 and C3.
18
70%
EN
Aluminium slag waste is a residue from aluminium recycling activities, classified as hazardous waste so its disposal into the environment without processing can cause environmental problems, including groundwater pollution. There are 90 illegal dumping areas for aluminium slag waste spread in the Sumobito District, Jombang Regency. This study aims to evaluate the quality of shallow groundwater surrounding aluminium slag disposal in the Sumobito District for drinking water. The methods applied an integrated water quality index (WQI) and heavy metal pollution index (HPI), multivariate analysis (principal component analysis (PCA) and hierarchical clustering analysis (HCA)), and geospatial analysis for assessing groundwater quality. The field campaign conducted 40 groundwater samples of the dug wells for measuring the groundwater level and 30 of them were analysed for the chemical contents. The results showed that some locations exceeded the quality standards for total dissolved solids (TDS), electrical conductivity (EC), and Al2+ . The WQI shows that 7% of dug well samples are in poor drinking water condition, 73% are in good condition, and 20% are in excellent condition. The level of heavy metal contamination based on HPI is below the standard limit, but 13.3% of the water samples are classified as high contamination. The multivariate analysis shows that anthropogenic factors and natural sources/geogenic factors contributed to shallow groundwater quality in the study area. The geospatial map shows that the distribution of poor groundwater quality is in the northern area, following the direction of groundwater flow, and is a downstream area of aluminium slag waste contaminants.
EN
This study presents how human-altered hydrographical settings (flow restrictions) impacts the natural distribution and community structure of copepods in the Kochi Backwaters (KBW), the largest monsoonal estuary along the southwest coast of India. This study is primarily based on an extensive seasonal sampling in the KBW and their comparison with a historical data set. Thannermukkom Barrage (TB) was built in the southern section of the KBW in the 1970s to prevent saline water intrusion to the upstream during the non-monsoon periods. Thirteen locations (1-4 in the downstream, 5-9 in the midstream, and 10-13 in the upstream) were sampled in this study over the entire stretch of the KBW during the Pre-Southwest Monsoon (PRM), Southwest Monsoon (SWM), and Post-Southwest Monsoon (PSWM). The overall effect of TB in the KBW is a seaward push of mesohaline conditions during all seasons with varying intensities. In response to the seaward push of mesohaline conditions, copepods Acartiella keralensis, Acartia plumosa, Acartia sp., Pseudodiaptomus annandalei, Pseudodiaptomus serricaudatus, Euterpina acutifrons and Oithona brevicornis showed a corresponding spatial shift for their highest abundance and diversity from midstream during PRM to the downstream during the SWM/PSWM. Multivariate and IndVal analysis demarcated many indicator species of copepods of different hydrographical settings in the KBW. A comparison with the historical data set showed that there is an apparent long-term change in hydrography, copepod composition and community structure in the upstream of the KBW due to TB.
EN
In Algeria, groundwater frequently serves as a main source of drinking water supply. Given the country’s geographical characteristics and water resource availability, many municipalities rely on groundwater to meet their drinking water needs.In this study, the quality of groundwater for drinking purposes in the northern region of the Middle Sébaou was assessed by obtaining hydrochemical data from ten groundwater samples in 2019. The study aimed to analyze and evaluate the hydrochemical composition of the groundwater using multivariate analysis and the water quality index (WQI) to determine its suitability for human consumption. Statistics showed that most of the groundwater analysis parameters are within acceptable limits except calcium (Ca2+) and bicarbonates (HCO3−) which exceed the potability standards set by the guidelines of the World Health Organization (WHO) for drinking water. Piper diagram demonstrates the existence of two hydrochemical facies: bicarbonate calcium and magnesium, and chloride as well as sulfate calcium and magnesium. According to the WQI values obtained in this study, ranging from 53.32 to 71.18, all of the groundwater samples exhibit good water quality based on the classification of the WQI method. On the basis of these results, the groundwater of the northern region of the Middle Sébaou is suitable for drinking purposes.
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