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1

Effects of the spatialisation of water-sounds sequences on the perception of traffic noise

Li Jian, Maffei Luigi, Pascale Aniello, Masullo Massimiliano

Vibrations in Physical Systems

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2022

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Vol. 33, nr 1

art. no. 2022110

EN

In the last decades, different researchers have shown the positive effects of informational masking (IM) on mitigating traffic noise perception and improving the local soundscape in urban parks. Most of these studies have tested various water sounds at different signal-to-noise ratios to optimise the selection and the sound levels to set the water sounds playback. However, less is known about the effects of the spatial distribution and movement of water sounds on the perception of the surrounding environment. Three different water-sounds sequences, and one control condition with only traffic noise, were created and used in an online experiment to investigate the role of spatialisation of water-sounds sequences. The sequences include a frontal fixed-position water sound, a two-position switching water sound and a four-position-randomised moving water sound. All of them were superimposed with a background traffic noise. Thirty-six subjects participated and answered an online questionnaire consisting of sets of items to describe the sound’s perception and feeling. The Perceived Restorativeness Scale (PRS-11) was also administered. The results have shown that introducing water-sounds sequences improves some components of the restorative qualities (Fascination and Being-Away). Moreover, different spatialisation settings of water sounds proved to modify people’s perception and feelings in different aspects, including attractiveness, smoothness, mechanicalness, stimulation, and nervousness.

2

Effect of spatial variation of spoil material properties on slope displacements under rapid drawdown of pit lakes

Halder Koushik, Doan Nhat-Phi, Garala Thejesh Kumar, Cui Ge, Kantesaria Naman, Heron Charles M., Marshall Alec M.

Górnictwo Odkrywkowe

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2022

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R. 63, nr 4

33--39

EN

In many European countries, lignite or brown coal is used as a fuel source in steam-electric power generation. Upon completion of mining activities, a reclamation plan is imperative to ensure environmental and social prosperity of local areas. Abandoned mine pits are often reclaimed by creating a pit lake. Reclamation of large lignite open pit mine sites may use large amounts of previous overburden materials or “spoils” to create the slopes of the pit lake. Spoils are anthropogenic materials with large spatial variation in properties, hence, considering mean values of shear strength and hydraulic parameters to assess stability and seasonal displacements will not fully simulate actual field conditions. This paper considers the effect of spatial variation on slope stability and ground movements during rapid drawdown events (a critical case) using coupled flow-deformation 2D finite element analyses, incorporating unsaturated soil suctions above the phreatic surface. Effects of heterogeneity and randomness of spoils on the response of the slope are considered through random field modelling and the Monte-Carlo simulation technique. Four lognormally distributed random variables (spoil cohesion, friction angle, void ratio, and permeability coefficient) are examined. The effect of spatial variability of spoils is shown to be important; a significant number of the random field analyses resulted in larger displacements compared to a benchmark deterministic analysis adopting uniform mean parameter values.

PL

W wielu krajach europejskich węgiel brunatny jest wykorzystywany jako źródło paliwa w energetyce parowo-elektrycznej. Po zakończeniu działalności górniczej konieczne jest opracowanie planu rekultywacji w celu zapewnienia środowiskowego i społecznego dobrostanu okolicznych obszarów. Opuszczone wyrobiska górnicze są często rekultywowane poprzez utworzenie w nich zbiorników wodnych. W rekultywacji dużych kopalni odkrywkowych węgla brunatnego do tworzenia zboczy zbiornika można wykorzystać duże ilości wcześniejszych materiałów nadkładowych lub „odpadowych”. Materiał zwałowy jest materiałem antropogenicznym o dużej przestrzennej zmienności właściwości, dlatego też przyjęcie średnich wartości wytrzymałości na ścinanie i parametrów hydraulicznych w celu oceny stabilności i sezonowych przemieszczeń nie będzie w pełni odzwierciedlać rzeczywistych warunków terenowych. W niniejszej pracy rozważano wpływ zmienności przestrzennej na stabilność zboczy i przemieszczenia gruntu podczas gwałtownego obniżenia poziomu wody (przypadek krytyczny), stosując sprzężone analizy 2D metodą elementów skończonych typu przepływ-deformacja, z uwzględnieniem ssania gruntów nienasyconych powyżej powierzchni freatycznej. Wpływ heterogeniczności i losowości materiału na zachowanie zbocza rozważany jest poprzez modelowanie pola losowego i technikę symulacji Monte-Carlo. Badane są cztery zmienne losowe (kohezja materiału, kąt tarcia, wskaźnik porowatości i współczynnik przepuszczalności) w rozkładach log-normalnych. Wykazano, że wpływ przestrzennej zmienności materiału zwałowego jest istotny; znaczna liczba analiz z wykorzystaniem pola losowego skutkowała większymi przemieszczeniami w porównaniu z wzorcową analizą deterministyczną, w której przyjęto jednolite średnie wartości parametrów.

3

Key Species of Phytoplankton in Eastern Part of Segara Anakan Indonesia Based on Season

Piranti Agatha Sih, Setyaningrum Nuning, Widyartini Dwi Sunu., Ardli Erwin Riyanto

Journal of Ecological Engineering

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2021

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Vol. 22, nr 3

135--142

EN

Phytoplankton blooms are a problem that often occurs in estuarine and coastal ecosystems. The changes in phytoplankton community species composition, diversity, biomass, and distribution were caused by the conditions of seasonal and temporal variation. The immediate location of the estuary ecosystem is near cities, where rapid economic growth and human activity tends to increase the pressure on the environment. The purposes of this research were to evaluate the seasonal and temporal variation and to determine the key species of phytoplankton in the eastern part of Segara Anakan which can cause a bloom based on season. The samples of phytoplankton were taken from 6 sites during April – September 2019 when the highest tide occurred during the dry and rainy seasons. The community structure were performed using primer software Ver 5 to find the similarity and / or differences of the phytoplankton community structure based on season. Simper analysis was used to determine key species (phytoplankton species) based on season and location. The community structure of phytoplankton in Segara chicks were composed by 5 divisions. During the dry season, Bacillariophyta was dominant (82%), whereas during the rainy season, Bacillariophyta (43%) and Chlorophyta (31%) and Cyanophyta (25%) were the dominant species. This study shows that the phytoplankton community structure in this estuary presents the environment conditions during the rainy season that increase the abundance of phytoplankton, especially of the species which may thrive into blooms. The most important species was Oscillatoria limosa that had the highest percentage of contribution.

4

Modelling spatial variation of extreme precipitation over Ho Chi Minh City under nonstationary conditio

Binh Le Thi Hoa, Agilan V., Umamahesh N. V., Rathnam E. V.

Acta Geophysica

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2019

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Vol. 67, no. 3

849--861

EN

Understanding the magnitude and spatial variation of extreme rainfall events are required for decision making and adaptation strategies for flood risk. In Ho Chi Minh City (HCMC), heavy rainfall, which is considered as a main cause of floods, witnessed an increase in frequency and magnitude in last few decades. Although nonstationarity in extreme rainfall has been proved in many places of the world, research into nonstationarity feature in extreme rainfall in HCMC has not been paid attention thoroughly. In this study, the spatial variation of extreme precipitation over Ho Chi Minh City is modelled under nonstationary condition. The generalized extreme value (GEV) distribution with location made a nonlinear function of time is applied to annual maximum daily rainfall. The study results show that the nonstationary GEV model is found to be superior in capturing extreme precipitation events when compared to the stationary GEV model. The extreme rainfall estimates under the stationary condition are lower than those under the nonstationary condition in most stations. Besides, the spatial variation of extreme rainfall under nonstationary condition shows a significant difference in extreme estimates between the periods of 1980–1984 and 2010–2014 in study area.

5

Geostatistical analysis of hydrochemical variations and nitrate pollution causes of groundwater in an alluvial fan plain

Yin Shiyang, Xiao Yong, Gu Xiaomin, Hao Qichen, Liu Honglu, Hao Zhongyong, Meng Geping, Pan Xingyao, Pei Qiuming

Acta Geophysica

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2019

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Vol. 67, no. 4

1191--1203

EN

Geostatistics was used in a typical alluvial fan to reveal its applicability to spatial distribution analysis and controlling mechanisms of groundwater chemistry. Normal distribution test and optimal geostatistical interpolation models for various groundwater quality indicators were discussed in this study. The optimal variogram model of each indicator was determined using prediction error analysis. The infuences of human activities and structural factors on the groundwater chemistry were also determined by variability intensity and the sill ratio. The results showed that nitrate content can be served as groundwater quality indicator, which was most sensitive to human activities. The nitrate concentration of both shallow and deep groundwater showed a decreasing trend from the northwest to the southeast. In addition, the spatial distribution of groundwater nitrate was associated with the land-use type and the lithological properties of aquifer. Rapid urbanization in the northwestern part intensifed groundwater extraction and aggravated the pollutant input. The central area showed little increase in nitrate content in the shallow and deep groundwater, and the efect of lateral recharge from the upstream water on the deep groundwater in the central area was greater than that of the vertical recharge from shallow groundwater. The present study suggests that geostatistics is helpful for analyzing the spatial distribution and distinguishing the infuences of anthropogenic and natural factors on groundwater chemistry.

6

Clutch size variation in agile frog Rana dalmatica on post-mining areas

Solský M., Smolová D., Doležalová J., Šebková K., Vojar J.

Polish Journal of Ecology

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2014

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Vol. 62, nr 4

789--799

EN

Clutch size is an important life history trait in amphibians, and it varies among and within species, populations and individuals. Within a population, its variation has been attributed to a positive relationship between females’ age or size and their fecundity as well as to spatio-temporal differences in environmental conditions. Therefore, clutch size has been shown to be both spatially and seasonally variable. We examined spatial and seasonal clutch size variation based upon two years of study involving 160 clutches of the Agile Frog Rana dalmatina Bonaparte, 1840 in 14 ponds within one spoil bank in the Czech Republic’s North Bohemian brown coal basin. The overall mean clutch size was 1295 (SD 596), which is one of the largest that has been reported. However, both clutch size and its variance differed considerably between the years. Clutch size also varied among the ponds. We found no relationship between clutch size and the distance of a breeding pond from alluvial forest, a typical wintering habitat. Despite existence at the site of many suitable reproduction habitats, the spoil bank does not offer the complex of all habitats needed for persistence of the R. dalmatina population. To protect that population, it is necessary to preserve not only breeding ponds on the spoil bank but also alluvial forest and, most importantly, the connectivity between these two crucial habitats.

7

Coefficient of Variation in Time and Spatial EMF Measurements Near Transmitting Stations

Lewicki R., Ługowski A.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2010

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nr 11

1688-1690

EN

The coefficient of variation (CoV) has been examined for measurements of electromagnetic fields (EMF) near high and medium power transmitting base stations in Poland. The time and spatial variation of signals at points of investigation (POI) has been measured for different locations and for different radiocommunication systems. It has been found that the time variation of signals in the far field region has Iow value (CoV < 11%). The spatial variation, considered as the change within the cube of size of 0,6 m x 0,8 m x 0,8 m, is higher (CoV < 33%) but is still Iow. It means that the probability that the human exposure assessment will be incorrect because of improper choice of the measurement time or location of probe in each POI is relatively Iow.

PL

Przedstawiono wyniki analizy współczynnika zmienności (CoV) natężenia pola elektrycznego zmierzonego w otoczeniu stacji nadawczych dużej i średniej mocy w Polsce. Zmienność w czasie i przestrzeni została zmierzona w punktach obserwacji (POI) dla sygnałów emitowanych przez różne systemy radiodyfuzyjne i radiokomunikacyjne. Stwierdzono, że w obszarze pola dalekiego zmienność poziomu mierzonych sygnałów jest stosunkowo mata (CoV < 11%). Zmienność przestrzenna rozpatrywana w sześcianie o wymiarach 0,6 m x 0,8 m x 0,8 m jest większa (CoV < 33%), ale nadal stosunkowo mała. Oznacza to, że prawdopodobieństwo niewłaściwej oceny zagrożenia ludzi elektromagnetycznym promieniowaniem niejonizującym, ze względu na nieoptymalny wybór czasu i położenia sondy w punkcie pomiarowym, jest względnie małe.