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1

Forecasting municipal waste accumulation rate and personal consumption expenditures using vector autoregressive (VAR) model

Bień Jurand

Production Engineering Archives

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2022

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Vol. 28, Iss. 2

150--156

EN

Accurate forecasting of municipal solid waste (MSW) generation is important for the planning, operation and optimization of municipal waste management system. However, it’s not easy task due to dynamic changes in waste volume, its composition or unpredictable factors. Initially, mainly conventional and descriptive statistical models of waste generation forecasting with demographic and socioeconomic factors were used. Methods based on machine learning or artificial intelligence have been widely used in municipal waste projection for several years. This study investigates the trend of municipal waste accumulation rate and its relation to personal consumption expenditures based on the yearly data achieved from Local Data Bank (LDB) driven by Polish Statistical Office. The effect of personal consumption expenditures on the municipal waste accumulation rate was analysed by using the vector autoregressive model (VAR). The results showed that such method can be successfully used for this purpose with an approximate level of 2.3% Root Mean Square Error (RMSE).

2

Statistics of tropospheric amplitude scintillation over selected locations in tropical Nigeria

Ashidi Ayodeji Gabriel, Ojo Joseph Sunday, Kareem Afan Idowu, Ojo Olusola Samuel, Emmanuel Israel

Acta Geophysica

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2021

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Vol. 69, no. 3

947--957

EN

Tropospheric scintillation depends signifcantly on any location’s prevailing weather condition, and its variation must be statistically analyzed to ensure accurate fade margin determination. This study examines the distribution of Ku-band amplitude scintillation across selected locations in tropical Nigeria. Eight years of daily averaged data of surface temperature and relative humidity were employed for computing scintillation intensity (σ) and amplitude (χ) using international telecommunications union recommended model across eighteen (18) stations, that are subdivided into four (4) regions and spread over tropical Nigeria. The data, spanning January 2010 to December 2017, were obtained from the archive of the European center for medium-range weather forecasts (ECMWF) with a resolution of 0.125° by 0.125°. Three (3) years of in-situ data of concurrently measured satellite radio beacons and primary radio-climatic parameters at Akure (7° 17′ N, 5° 18′ E, 358 m), South-west Nigeria, were employed for comparison and validation. Statistical analyses involving time series, probability density, and cumulative distribution functions were performed on the scintillation dataset annually. Results indicate that the magnitude of tropospheric amplitude scintillation varies across diferent locations; nevertheless, it exhibits a similar distribution pattern characterized by the generalized extreme value (GEV) probability density function (pdf). The study has shown the need to incorporate the scintillation component into the fade mitigation architecture of telecommunication systems in tropical Nigeria while considering its regional variability. Also, experimental validation of the observations raised in this study should be encouraged at all the locations for better prediction accuracy.

3

214Bi/214Pb radioactivity ratio three-year monitoring in rainwater in Prague

Ambrosino Fabrizio, Thinová Lenka, Hýža Miroslav, Sabbarese Carlo

Nukleonika

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2020

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Vol. 65, No. 2

115--119

EN

Continuous monitoring of natural gamma radiation in air has been carried out, during December 2014 – January 2018, with 1-min cyclic measurement in Prague, Czech Republic using a NaI(Tl) probe. The 214Bi/214Pb ratio as a tracer in rainwater has been investigated to study its variations related to both the ambient dose equivalent rate per hour and the amount of rainfall. A hybrid methodology for time series analysis, composed of the aggregation of two signal decomposition methods (multiple linear regression and empirical mode decomposition) and one forecasting method (support vector regression), has been applied to identify the anomalies in the studied signals in order to better find correlations among them. The results show a strong correlation between the ambient dose equivalent rate and the 214Bi/214Pb ratio values and between both these signals and rainfall amount≥5 mm/h. Furthermore, the considered descendants of radon are mainly responsible for the overall ambient dose equivalent rate.

4

Separation of split shear waves based on a hodogram analysis of HTI media

Yang Y., Lu J., Wang Y.

Acta Geophysica

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2018

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Vol. 66, no. 4

643--658

EN

Although the shear-wave birefringence phenomenon affects the imaging of converted shear waves, it also provides a considerable amount of information on subsurface fracture development. Therefore, it is significant to separate split shear waves before seismic interpretation and reservoir prediction. In this paper, we propose a new method of split shear waves separation based on the polarization directions derived from hodogram analysis. Through the hodogram analysis, we find that the split shear-wave particle motions are within the range of a specific and fixed rectangle, which have relations with the fracture azimuth in strata. In addition, we found that a couple of split shear waves can only be fitted to the unique trajectory rectangle through the theoretical derivation. Based on this, we establish the trajectory rectangle through the wave vector calculation and calculate the fracture azimuth according to the fact that the one edge of the trajectory rectangle is along or perpendicular to the fracture azimuth. Synthetic data analysis shows that the calculation accuracy of fracture azimuth under the constraint of trajectory rectangle is less affected by the time delay between split shear waves than using the method of eigenvector–eigenvalue decomposition (EED). Therefore, we can obtain better results for separation of split shear waves using our method than using EED. Eventually, we propose an approach of layer stripping to deal with the problem that shear wave split several times due to the situation that different strata have different fracture azimuths. Synthetic data test indicates that our method can achieve higher calculation efficiency and faster convergence speed than the conventional eigenvector–eigenvalue decomposition method, even though the data are of a low signal-to-noise ratio. Moreover, field data applications show the effectiveness and potential of our method.

5

Road safety analysis in Poland using time-series modelling techniques

Zukowska J.

Journal of Polish Safety and Reliability Association

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2012

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Vol. 3, No. 1

109--112

EN

A number of international studies argue that there is a correlation between the number of traffic fatalities and the degree of public activity. The studies use the unemployment rate to support that argument. As unemployment grows miles travelled fall, a factor known to affect road safety. This relationship seems to be true for Poland, as well. The model presented in the paper is intended to prove it. It is a structural time-series local level model with the explanatory variable (the unemployment rate) and some interventions. Because of the dynamic nature of traffic safety developments it lends itself very well to modelling in that way.

6

Wykorzystanie modelu Wintersa do prognozowania jakości powietrza powiatu kędzierzyńsko-kozielskiego

Szewczyk M., Tłuczak A.

Woda-Środowisko-Obszary Wiejskie

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2010

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T. 10, z. 3

283-296

PL

Powiat Kędzierzyn-Koźle jest jednostką administracji terytorialnej i samorządowej województwa opolskiego, w południowo-zachodniej Polsce. Istniejąca w Kędzierzynie-Koźlu sieć monitoringu powietrza obejmuje dziś tylko jedną w pełni automatyczną stację monitoringu. Emisja wielu zanieczyszczeń powietrza w Kędzierzynie-Koźlu zmniejszyła się znacząco od 1992 r., jednak od 2007 r. stężenie NO2 i pyłu zawieszonego PM10 w powietrzu się nie zmniejszyło. Zmniejszenie stężenia zanieczyszczeń powietrza jest nadal konieczne. Prognozowanie jakości powietrza to jeden z kluczowych elementów współczesnego zarządzania jakością powietrza. W artykule przedstawiono modele i prognozy stężenia SO2, NO2, CO, O3 i PM10, skonstruowane na podstawie danych, pozyskanych z automatycznej stacji monitoringu w Kędzierzynie-Koźlu.

EN

Kędzierzyn-Koźle County is a unit of territorial administration and local government in Opole Voivodeship, south-western Poland. The existing air monitoring network in Kędzierzyn-Koźle comprises only one fully automatic monitoring station now. In Kędzierzyn-Koźle, emissions of many air pollutants have substantially decreased since 1992. However, since 2007, measured concentrations of NO2 and particulate matter PM10 in the air have not shown any improvement. The need to reduce air pollution still remains an important issue. Air quality forecasting is one of the core elements of contemporary air quality management. This paper presents models and forecasts of SO2, NO2, CO, O3 and PM10 concentrations based on data from automatic monitoring station in Kędzierzyn-Koźle.

7

Environmetric Study of the Seasonal Patterns (1989-1998) in the Water Quality of the Struma River Basin, Bulgaria

Nikolov N., Mihailov G., Simeonov V., Mirinchev G.

Chemia i Inżynieria Ekologiczna

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2003

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Vol. 10, nr 8

763-771

EN

By the application of time-series analysis an estimation of the long-term water quality of the Struma river basin is performed. Several typical patterns of seasonal behaviour could be found reflecting the location of rural, urban, tributary and background sampling sites. Although it is quite difficult to specify a strict seasonal pattern along the Stroma river stream, some stable seasonality for the chemical indicators is obtained for the various sites like summer maximums caused probably by the lower water level for most of the sites, winter maximums for anthropogenic species at urban sites or at tributary sites due probably to the effect of waste waters, maximums due to agriculture activity etc. In this way a summary of the long-term water quality monitoring is obtained.

PL

Dokonano długoterminowego oznaczenia jakości wody w dorzeczu rzeki Struma poprzez zastosowanie analizy serii czasowych. Można znaleźć kilka typowych sezonowych zachowań odzwierciedlających lokalizacje miejsc pobierania próbek: na terenach wiejskich, miejskich, w pobliżu ujść dopływów oraz charakterystycznych dla tła. Mimo że dość trudne jest określenie ściśle sezonowych prawidłowości tych zmian wzdłuż biegu rzeki Struma, jednak udało się wykryć sezonowość wartości indykatorów chemicznych w różnych miejscach. Są to takie zmiany sezonowe, jak letnie maksima spowodowane prawdopodobnie niskim poziomem wody dla większości miejsc pobierania próbek, zimowe maksima o charakterze antropogennym charakterystycznym dla obszarów miejskich lub w pobliżu ujść dopływów będące wynikiem zrzutu wód ściekowych, maksima wynikające z działalności rolniczej itd. Otrzymano w ten sposób długoterminowe prawidłowości dotyczące danych monitoringu jakości wód.

8

Assessment of the Atmospheric Pollution in the Industrial Region of Devnia, Bulgaria

Stanimirova I., Simeonova P., Simeonov V.

Chemia i Inżynieria Ekologiczna

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2003

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Vol. 10, nr 5

381-388

EN

The present study deals with long-term pollution monitoring data observation in the atmosphere of the industrial region of Devnia, Bulgaria. The species in consideration: S02, CO, H2S, 03, total suspended particles (TSP) and non-methane hydrocarbons (NMHC) are analysed with respect to their annual or monthly trend, to their seasonal behavior and source apportioning. Various multivariate statistical approaches (Iinear trend analysis, time-series analysis, principal components analysis, cluster analysis) are used to interpret and model the monitoring data sets. It is shown that over the whole time period the pollutant concentrations, although higher than the allowed levels, do not tend to increase. Seasonal information is obtained for all species with typical winter maxima and summer minima for TSP and ozone, summer maxima and winter minima for sulfur dioxide and non-methane hydrocarbons and more non-specific seasonality for carbon monoxide and hydrogen sulfide. Finally, four latent factors are identified as responsible for the pollution pattern of the region, conditionally named "dust", "organic", "fertilizer" and "warming" factor. In such a way a better emission source apportioning is possible.

PL

Analizowano dla przemysłowego regionu Devnia, Bułgaria dane długoterminowego monitoringu zanieczyszczenia powietrza atmosferycznego: S02, CO, H2S, O), całkowity pył zawieszony (TSP) i węglowodory niemetanowe (NMHC). Badano zmiany miesięczne i roczne tych zanieczyszczeń ich zachowanie się w różnych sezonach oraz przypisywano je poszczególnym źródłom. Do interpretacji uzyskanych danych monitoringu oraz ich modelowania stosowano różne wielowariancyjne metody statystyczne (analizy linii trendu, analizy serii czasowych, analizy głównych składników, analizę klasterów). Stwierdzono, że podczas całego badanego okresu stężenia polutantów, chociaż były większe niż poziom dozwolony, to jednak nie wzrastały. Otrzymano sezonowe zależności dla wszystkich badanych polutantów: z typowymi zimowymi maksimami i letnimi minimami dla TSP i ozonu, letnimi maksimami i letnimi minimami dla S02 i NMHC oraz raczej nieokreśloną sezonowością w przypadku CO i H2S. Na koniec, cztery ukryte czynniki zostały zidentyfikowane jako odpowiedzialne za sposoby zanieczyszczania regionu, zostały one nazywane odpowiednio, jako czynnikiem "pyłowym", "organicznym", "nawozowym" oraz "cieplnym". Takie podejście umożliwia lepszą klasyfikację źródeł emisji.

9

Understanding the dynamics of bank vole populations: demographic variability, stochasticity and density dependence

Yoccoz N., Stenseth N.

Polish Journal of Ecology

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2000

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Vol. 48, Suppl.

75-86

EN

The observed variability of population dynamics in influenced by many interacting components, most of them being difficult to estimate. Sampling variance, demographic and environmental stochasticity, together with density dependence and more deterministic changes in the environment such as changes in forestry practice and landscape patterns, simultaneously affect our understanding of bank vole population dynamics patterns. Integrating these difference variability components in a common framework is a considerable challenge. We explore in this paper some of the tools currently available for analysing population dynamics and demographic patterns in the bank vole, Clethrionomys glareolus. The study of an alpine population of bank voles is used to illustrate how demographic studies and time-series analysis may be associated in the future.