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1

Evaluation of groundwater in aluminium slag disposal area

Putranto Thomas Triadi, Febriane Wenny

Journal of Water and Land Development

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2023

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no. 57

78--90

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.

2

Identifying Key Parameters Influencing Soil Quality at Various Depths in Tram Chim National Park, Dong Thap Province, Vietnam

Giao Nguyen Thanh, Nhien Huynh Thi Hong, Dan Truong Hoang, Ni Duong Van

Journal of Ecological Engineering

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2023

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Vol. 24, nr 2

81--91

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.

3

Groundwater Quality Assessment of the Northern Region of the Middle Sébaou in Algeria, Using Water Quality Index and Multivariate Analysis

Rezig Amina, Mansour Dalila, Saggai Sofiane

Ecological Engineering & Environmental Technology

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2023

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Vol. 24, iss. 7

148--153

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.

4

Combining multivariate statistical analysis to shed light on distribution and interaction of halogens in two economic ports along Red Sea Coast in Egypt

Zokm Gehan M. El, El-Said Ghada F., El Sayed Abeer A.M.

Oceanologia

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2022

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No. 64 (1)

103--106

EN

Mabahiss Bay and Safaga Bay are two important ports along the Red Sea coast of Egypt. The present study is the first to monitor halogen concentrations in these two ports. Certain halogens (F, Cl, Br and I) in coastal waters and sediments exhibited different behaviors. Fluoride (1.92–8.31 mg/L and 0.34–1.24 mg/g), chloride (20.76–22.68 g/L and 0.38–8.31 mg/g), bromide (95.90–151.84 mg/l and 6.66–50.61 mg/g), and iodide (2.77–39.19 μg/L and 1.71–3.76 μg/g) appeared in the seawater and sediments of Mabahiss Bay, respectively. In Safaga Bay, F, Cl, Br and I yielded ranges of (1.80–10.15 mg/L and 0.14–0.74 mg/g), (21.47–22.57 g/L and 0.68–1.42 mg/g), (15.98–146.51 mg/L and 6.13–74.59 mg/g) in seawater and sediments, respectively. In Mabashis Bay exclusively, the bromide and iodide levels in seawater increased significantly, and the sediments were vice versa. The average fluoride value in the two ports' seawater was higher than that in the unpolluted Mediterranean Sea. In contrast, the average bromide content in Mabahiss Bay seawater exceeded the Mediterranean Sea level. The seawater chloride content of the two ports was within the Mediterranean seawater's value, but the iodide concentration was lower than that of the unpolluted seawater. The application of different multivariate statistical techniques showed that halogen's distribution and halogen's geochemical characteristics control interaction in each region, ground flux, and proximity to human sources.

5

Use of Multivariate Statistical Analysis of Hydrochemical Data for the Identification of the Geochemical Processes in the Tirana-Fushe Kuqe Alluvial Aquifer, North-Western Albania

Raço Endri, Beqiraj Arjan, Cenameri Sabina, Jahja Aurela

Journal of Ecological Engineering

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2022

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Vol. 23, nr 8

327--340

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.

6

Impact of human-altered hydrographical setting on the Copepod community structure in an extensive tropical estuary along the southwest coast of India

Nagarathinam Arunpandi, Retnamma Jyothibabu, Loganathan Jagadeesan, Singaram Parthasarathi, Arayillath Anjusha, Jose Albin Konnakkamannil

Oceanologia

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2021

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No. 63 (1)

115--132

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.

7

Predicting motor oil condition using artificial neural networks and principal component analysis

Rodrigues Joao, Costa Ines, Farinha J. Torres, Mendes Mateus, Margalho Luis

Eksploatacja i Niezawodność

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2020

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Vol. 22, no. 3

440--448

EN

The safety and performance of engines such as Diesel, gas or even wind turbines depends on the quality and condition of the lubricant oil. Assessment of engine oil condition is done based on more than twenty variables that have, individually, variations that depend on the engines’ behaviour, type and other factors. The present paper describes a model to automatically classify the oil condition, using Artificial Neural Networks and Principal Component Analysis. The study was done using data obtained from two passenger bus companies in a country of Southern Europe. The results show the importance of each variable monitored for determining the ideal time to change oil. In many cases, it may be possible to enlarge intervals between maintenance interventions, while in other cases the oil passed the ideal change point.

PL

Bezpieczeństwo i wydajność silników takich, jak silniki Diesla czy gazowe, a nawet turbiny wiatrowe, zależą od jakości i stanu oleju smarowego. Stanu oleju silnikowego ocenia się na podstawie ponad dwudziestu zmiennych, z których każda ulega wahaniom w zależności od typu i zachowania silnika oraz innych czynników. W niniejszym artykule opisano model, który pozwala na automatyczną klasyfikację stanu oleju, z wykorzystaniem sztucznych sieci neuronowych i analizy składowych głównych. Badania przeprowadzono na podstawie danych uzyskanych od dwóch przewoźników pasażerskich działających na terenie jednego z krajów położonych na południu Europy. Wyniki pokazują, że każda z monitorowanych zmiennych ma znaczenie dla określenia idealnego czasu na wymianę oleju. Podczas gdy w wielu przypadkach w badanych przedsiębiorstwach możliwe było zwiększenie odstępów czasowych między działaniami konserwacyjnymi, w innych, idealny moment wymiany oleju został przekroczony.

8

The application of the geo-accumulation index and geostatistical methods to the assessment of forest soil contamination with heavy metals in the Babia Góra National Park (Poland)

Łyszczarz Stanisław, Błońska Ewa, Lasota Jarosław

Archives of Environmental Protection

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2020

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Vol. 46, no. 3

69--79

EN

The aim of this study was the application of the geo-accumulation index and geostatistical methods to the assessment of forest soil contamination with heavy metals in the Babia Góra National Park (BGNP). For the study, 59 sample plots were selected to refl ect all soil units (soil subtypes) in the studied area and take into account various forms of terrain. The content of organic carbon and total nitrogen, pH, hydrolytic acidity, the base cations and heavy metals content were determined in the soil samples. The geo-accumulation index (Igeo) was calculated, enabling estimation of the degree of soil pollution. The tested soils are characterized by strong contamination with heavy metals, especially with lead. The concentration of heavy metals in the surface horizons of the tested soils exceeds allowable concentration. The content of heavy metals was related to the content of soil organic matter, soil acidity and altitude. Higher altitudes are dominated by coniferous tree stands, which are accompanied by acidic, poorly decomposed organic horizons. Our study has confi rmed the impact of pollutants transported from industrial areas on the amount of heavy metals in soils of the BGNP.

9

Anthropometric and strength profiles of professional handball players in relation to their playing position – multivariate analysis

Lijewski Marcin, Burdukiewicz Anna, Pietraszewska Jadwiga, Stachoń Aleksandra, Andrzejewska Justyna, Chromik Krystyna

Acta of Bioengineering and Biomechanics

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2019

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Vol. 21, no. 4

147--155

EN

In team sports, the varied levels of physical demand associated with different field positions are reflected in the morphofunctional features of the players. The aim of this work was to recognize how the playing position in the team depends on the anthropometric profiles and the strength level of professional handball players. Methods: A body mass, stature, lower and upper extremity length, circumferences and skinfolds were measured in the male professional athletes. The body composition was analysed using a bioelectrical impedance method. Additionally, hand grip and back strength were measured. A statistical analysis was carried out using routinely statistic methods and principal component analysis. Results: Pivot players usually have the most athletic figure in terms of size and weight and relatively short legs. The backs are characterized by the android body type and low subcutaneous fat content, and a large mass of body cells. The backs and pivots have the same strength of back and hand grip. Goalkeepers have relatively long upper and lower limbs and high back and hand grip strength. The wingers are usually slender, have medium length limbs, low body fat percentage, significant extracellular mass and the lowest muscle strength. Conclusions: The results of the multivariate analysis were a notable and valuable addition to the study of morphological and strength differences in a group quite homogeneous like a handball team. The principal component analysis allowed for a reduction of the multidimensional structure to three variables describing body massiveness, strength, and the length and height aspect of the body.

10

Statistical evaluation of the effect of secondary municipal wastewater and solid waste leachate on ground water quality at Lawspet in Puducherry, India

Nathan N. S., Saravanane R., Sundararajan T.

Environment Protection Engineering

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2018

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Vol. 44, nr 1

85--102

EN

At Lawspet area in Puducherry, India, a unique situation of co-disposal of solid waste dumping and secondary wastewater disposal on land, prevails simultaneously within the same campus. So an attempt is made to assess the combined effect of this co-disposal on the environmental quality and pollution effects on groundwater quality with a view to correctly monitor the situation. Multivariate statistical analysis like hierarchical cluster analysis (HCA) and discriminant analysis (DA) were employed. HCA was performed on borewells, physiochemical parameters and seasons. Borewell clustering identified four clusters illustrating varying degree of groundwater contamination. In parameter clustering, two major clusters were formed indicating hardness and anthropogenic components. Temporal clustering identified three major clusters indicating pre-monsoon, monsoon and post-monsoon. Discriminant analysis revealed nine significant parameters which discriminate four clusters qualitatively affording 86% correct assignation to discriminate among the clusters. Also three major components viz. anthropogenic, hardness and geogenic responsible for groundwater quality in the study area were identified. Conclusively the investigation revealed that the direction of the contaminant transport is towards the southeast direction of the study area, where all the borewells (100%) are affected.

11

Analysis of synoptic patterns in relationship with severe rainfall events in the Ebre Observatory (Catalonia)

Pérez-Zanón N., Casas-Castillo M. C., Peña J. C., Aran M., Rodríguez-Solà R., Redaño A., Solé G.

Acta Geophysica

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2018

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Vol. 66, no. 3

405--414

EN

The study has obtained a classification of the synoptic patterns associated with a selection of extreme rain episodes registered in the Ebre Observatory between 1905 and 2003, showing a return period of not less than 10 years for any duration from 5 min to 24 h. These episodes had been previously classified in four rainfall intensity groups attending to their meteorological time scale. The synoptic patterns related to every group have been obtained applying a multivariable analysis to three atmospheric levels: sea-level pressure, temperature, and geopotential at 500 hPa. Usually, the synoptic patterns associated with intense rain in southern Catalonia are featured by low-pressure systems advecting warm and wet air from the Mediterranean Sea at the low levels of the troposphere. The configuration in the middle levels of the troposphere is dominated by negative anomalies of geopotential, indicating the presence of a low or a cold front, and temperature anomalies, promoting the destabilization of the atmosphere. These configurations promote the occurrence of severe convective events due to the difference of temperature between the low and medium levels of troposphere and the contribution of humidity in the lowest levels of the atmosphere.

12

BIM w projektowaniu konstrukcji. Optymalizacja kratownicy przestrzennej

Radzik Ł.

Builder

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2017

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R.21, nr 4

75--77

PL

W artykule zostało przedstawione wykorzystanie technologii BIM przy optymalizacji kratownicy przestrzennej. Została zobrazowana analiza wielowariantowa kratownicy dla ustalonych wartości parametrów geometrycznych oraz zaproponowano schemat postępowania przy optymalizacji tego typu konstrukcji. Na podstawie przeprowadzonych obliczeń wyciągnięto wnioski dotyczące zaleceń odnośnie do kształtowania kratownic przestrzennych oraz wrażliwości wyników wobec wartości przyjętych parametrów.

EN

The article shows the use of BIM technology in the optymalization of space frame. Multivariate analysis of structure for fixed values of geometrical parameters was illustrated. Worklow for optimizing this type of construction was proposed. Conducted calculations shown some recommendations for the shape of space frame forming.

13

Scale-dependent environmental control of mesozooplankton community structure in three aquaculture subtropical bays of China

Sun D., Liu Z., Wang C.

Oceanologia

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2016

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No. 58 (2)

124--134

EN

Most subtropical bays of China have been under heavy pollution since the late 1990s, mainly because of the rapid development of aquaculture and discharge of industrial and agricultural wastewater. Some projects were conducted to investigate the zooplankton community in these bays, but those studies were less focused on the relationship between spatial structure of mesozooplankton community and environmental variables in/among bays. The mesozooplankton community structures in relation to physical, chemical and biological variables were studied in three subtropical bays of China with seasons and different spatial scales during 2000 and 2002–2003. Data were collected on temperature (T), salinity (S), concentration of chlorophyll a (Chl a), pH, dissolved oxygen (DO), soluble reactive phosphate (SRP), dissolved inorganic nitrogen (DIN), chemical oxygen demand (COD), suspended particle material (SPM) and mesozooplankton taxonomic abundances. Correlation analysis showed that the main environmental factors correlated to the total abundance of mesozooplankton in these subtropical bays were Chl a, temperature, COD and SRP. Multivariate analysis indicated that DO, Chl a and temperature were the principal factors in influencing spatial differentiation of zooplankton community structure in the inter-bay scale. At the within-bay scale, the influencing factors were different among bays; the main factors were physical variables for Xiangshan Bay and Sanmen Bay, while chemical variables for Yueqing Bay, respectively. The results revealed that the environmental variables that affected spatial structure of mesozooplankton community were different at inter-bay scale and within-bay scales, and zooplankton community was more influenced by chemical (e.g. nutrients/ammonia) variables when under serious eutrophication condition, while it would be more influenced by physical variables (temperature/salinity) when under less eutrophic conditions.

14

The use of multivariate analysis of the radon variability in the underground laboratory and indoor environment

Filipović J., Maletić D., Udovičić V., Banjanac R., Joković D., Savić M., Veselinović N.

Nukleonika

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2016

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Vol. 61, No. 3

357--360

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.

15

Study of the influence of temperature and water level of the reservoir about the displacement of a concrete dam

Oro S. R., Mafioleti T. R., Chaves Neto A., Garcia S. R. P., Neumann C.

International Journal of Applied Mechanics and Engineering

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2016

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Vol. 21, no. 1

107--120

EN

Multivariate techniques are used in this study to analyze the monitoring data displacements of a concrete dam, measured by means of pendulums, extensometer bases and multiple rod extensometers, taking into account the action of environmental conditions, bounded by the surface temperature of the concrete at ambient temperature and the tank water level. The canonical correlation analysis is used to evaluate the influence of environmental variables in the displacement of structures and dam foundations. The factor analysis is used to identify data sources of variability and order the sensors according to the action of factors. The dates of the measurements are grouped according to similarities in the present observations, by applying the cluster analysis. Then the discriminant analysis is used to assess the groups as to their homogeneity. The results demonstrate that the techniques used for distinguishing the dam responses and identify the effects of changes in environmental conditions on the displacements of the structures and dam foundations.

16

Quantitative studies of the calcareous nannoplankton of Sarmatian deposits : case studies in the Sieniawa–Rudka area (Outer Carpathian Foredeep, Poland)

Lelek D., Oszczypko-Clowes M., Oszczypko N.

Annales Societatis Geologorum Poloniae

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2016

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Vol. 86, No. 1

29--57

EN

The aim of this study was the qualitative and quantitative analysis of the calcareous nannofossil assemblages of the Machów Formation, belonging to the supra-evaporitic complex of the Polish Carpathian Foredeep Basin (PCFB). The work was concentrated in the eastern part of the PCFB, in the Sieniawa–Rudka area (Ryszkowa Wola Horst). Samples were collected from the Rudka-13 and Wylewa-1 boreholes. On the basis of calcareous nannoplankton, these deposits were assigned to the upper part of the NN6 Zone combined with the NN7 Zone, which corresponds to the Sarmatian s.s. of the Central Paratethys (upper Serravallian of the Mediterranean scale). Conclusive determination of the biozone NN7 was problematic, owing to the absence of the rare zonal marker species Discoaster kugleri. The typical association of the undivided NN6–NN7 Zone was of low species diversity and usually dominated by Coccolithus pelagicus, Cyclicargolithus floridanus and Reticulofenestra pseudoumbilica (> 7 µm). On the basis of the relative abundance of species, a significant amount of redeposition was deduced. The reworked nannofossils were mostly Eocene in age. The Oligocene, Early Miocene and Late Cretaceous species occurred much less frequently. The dominance of Eocene forms indicates the Carpathians as the main supply area. The Late Cretaceous taxa may have originated from the Senonian marly deposits of the Miechów Trough in the north. Statistical treatment of the quantitative data was performed using multivariate cluster analysis and Nonmetrical Multidimensional Scaling (nMDS). The composition of the calcareous nannofossil assemblages, together with the high percentage of allochthonous taxa, indicate a shallow, coastal environment with a high supply of nutrients.

17

The System Functions MAOPCs for Analysis and Optimization Of Linear Periodically Time-Variable Circuits Based on the Frequency Symbolic Method

Shapovalov Y., Mandziy B., Bachyk D.

Przegląd Elektrotechniczny

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2015

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R. 91, nr 7

39-42

EN

In this paper we considered the following provisions: the architecture of system functions MAOPCs and examples of its application to solve tasks of multivariate analysis of LPTV circuits based on the frequency symbolic method. The method is based on approximation of transfer functions of LPTV circuits in the form of trigonometric polynomials of the Fourier. The system functions MAOPCs is implemented in the environment of MATLAB.

PL

W pracy zaprezentowano układ funkcji do symbolicznej analizy i optymalizacji obwodów parametrycznych, zmiennych w czasie. Metoda jest oparta na aproksymacji transmitancji obwodu parametrycznego za pomocą trygonometrycznego wielomianu Fouriera. Zaproponowany zbiór funkcji jest zaimplementowany w środowisku programu MATLAB.

18

Exploiting Stein's paradox in analysing sparse data from genome-wide association studies

Valenta Z., Kalina J.

Biocybernetics and Biomedical Engineering

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2015

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Vol. 35, no. 1

64--67

EN

Unbiased estimation appeared to be an accepted golden standard of statistical analysis ever until the Stein's discovery of a surprising phenomenon attributable to multivariate spaces. So called Stein's paradox arises in estimating the mean of a multivariate standard normal random variable. Stein showed that both natural and intuitive estimate of a multivariate mean given by the observed vector itself is not even admissible and may be improved upon under the squared-error loss when the dimension is greater or equal to three. Later Stein and his student James developed so called 'James–Stein estimator', a shrunken estimate of the mean, which had uniformly smaller risk for all values in the parameter space. The paradox first appeared both unintuitive and even unacceptable, but later it was recognised as one of the most influential discoveries of all times in statistical science. Today the 'shrinkage principle' literally permeates the statistical technology for analysing multivariate data, and in its application is not exclusively confined to estimating the mean, but also the covariance structure of multivariate data. We develop shrinkage versions of both the linear and quadratic discriminant analysis and apply them to sparse multivariate gene expression data obtained at the Centre for Biomedical Informatics (CBI) in Prague.

19

Zastosowanie statystycznych metod wielowymiarowej analizy porównawczej w zarządzaniu rozwojem zaopatrzenia w wodę i sanitacji obszarów wiejskich w Polsce w latach 2000–2012

Skowronek-Grądziel A., Kołwzan W., Dziubek A.M.

Ochrona Środowiska

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2014

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Vol. 36, nr 4

61--68

PL

W pracy postawiono hipotezą badawczą, że od początku XXI wieku, w miarę upływu czasu, następuje systematyczny rozwój infrastruktury technicznej służącej zaopatrzeniu w wodę i sanitacji obszarów wiejskich w Polsce. Jednocześnie przyjęto, że w osiągnięciu tego celu może pomóc zastosowanie wielowymiarowych metod analizy statystycznej. Na podstawie przeprowadzonej analizy 25 zmiennych z lat 2000, 2003, 2005 i 2012 oszacowano ich średnie arytmetyczne, wariancje, odchylenia standardowe oraz wartości współczynników zmienności. Na podstawie analizy statystycznej wykazano, że wraz z upływem czasu wskaźniki określające infrastrukturę techniczną z zakresu wodociągów i kanalizacji na obszarach wiejskich w Polsce ulegają stałemu rozwojowi, czyli w wyraźny sposób kształtuje się świadomość w zakresie konieczności ochrony zasobów wodnych. Świadczą o tym wartości średnich (trend liniowy) w metodzie Hellwiga w odniesieniu do zmiennych centralnych, których łączna wartość, w przypadku ośmiu wyznaczonych poziomów zmiennych, wzrosła z 61 w okresie początkowym (2000 r.) do 67 w najbardziej aktualnym czasie badania (2012 r.). Otrzymane wyniki dostarczają decydentom znaczącą wiedzę ilościową i merytoryczną, niezbędną do podejmowania decyzji o znaczeniu ogólnokrajowym. Umożliwiają one także kompleksowe spojrzenie i bieżącą ocenę sytuacji w zakresie zaopatrzenia w wodę oraz odprowadzania ścieków i zagospodarowania odpadów na danym obszarze. Łączy się to ściśle z podstawowymi współcześnie rozumianymi funkcjami zarządzania w zakresie podejmowania decyzji na szczeblu centralnym (np. przez Ministerstwo Ochrony Środowiska).

EN

A research hypothesis was formulated that since the beginning of the 21st century a systematic progress had been made in technical infrastructure serving water supply and sanitation of rural areas in Poland. Concurrently, it was assumed that multivariate methods of statistical analysis could help achieve the set goal. The analysis of 25 variables from the years 2000, 2003, 2005 and 2012 allowed for the estimation of their arithmetic means, variances, standard deviations and coefficients of variation. In terms of water supply and sewerage systems, the statistical analysis demonstrated a steady development of indicators for technical infrastructure in rural areas in Poland. Thus, awareness in respect of the need for water supply protection clearly increases. The above conclusion is supported by the means in the Hellwig’s method (linear trend) in relation to the central variables. The combine value of the latter, calculated for the eight sets of variables, increased from 61 in the initial period (year 2000) to 67 in the most recent study period (2012). The results received provide the decisionmakers with extensive quantitative and qualitative knowledge, essential for taking decisions at the national level. In addition, they allow for comprehensive approach and on-going evaluation of the situation with regard to water supply as well as sewage disposal and waste management in any given area. This is strictly connected with currently understood fundamental functions of management with regard to decision-making at the central level (e.g. by the Ministry of the Environment).

20

Analiza wielowariantowa zintegrowanego systemu zaopatrzenia budynku w energię

Pisarev V., Rybak-Wilusz E., Sawicka P.

Zeszyty Naukowe Politechniki Rzeszowskiej. Budownictwo i Inżynieria Środowiska

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2012

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z. 59, nr 2/II/II

611--624

PL

W referacie przedstawiono porównanie wariantowe współpracy istniejącej instalacji hybrydowej wykorzystującej ciepło z miejskiej sieci cieplnej i energię promieniowania słonecznego z układem kogeneracyjnym oraz pompą ciepła, w domu studenckim „Promień” Politechniki Rzeszowskiej. Wykonano analizę ekonomiczną w celu określenia opłacalności zaproponowanych rozwiązań.

EN

The paper presents the analysis of integrated energy supply system, in the hostel „Ray” of Rzeszow Technical University. The current hybrid installation uses the heat with district heating station and solar. At the work was described variant comparing the hybrid installation cooperating with the cogeneration system and with heat pump. In terms of the cost-effectiveness the proposed solutions were compared.