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Spatio-temporal variation of rainfall over Bihar State, India

-term variation of seasonal precipitation in Poland]. Woda-Środowisko-Obszary Wiejskie. T. 12. Z. 38 p. 45–60. D ugam S.S., K akade S.B. 2003. Indian monsoon variability in relation to regional pressure index. Journal of Earth System Science. Vol. 112. Iss. 4 p. 521–527. D uhan D., P andey A. 2013. Statistical analysis of long term spatial and temporal trends of precipitation during 1901–2002 at Madhya Pradesh, India. Atmospheric Research. Vol. 122 p. 136–149. G allant A.J., H ennessy K.J., R isbey J. 2007. Trends in rainfall indices for six Australian

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On Nonlinear Waves in the Spatio-Temporal Dynamics of Interacting Populations

Abstract

In this paper the spatial-temporal dynamics of the members of interacting populations is described by means of nonlinear partial differential equations. We consider the migration as a diffusion process influenced by the changing values of the birth rates and the coefficients of interaction between the populations. The general model is reduced to analytically tractable partial differential equations (PDE) with polynomial nonlinearity up to third order for the particular case of one population and one spatial dimension. We obtain an analytical solution which describes nonlinear kink and solitary waves in the population dynamics by applying the modified method of simplest equation to the described model.

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Temporal distribution of linear densities of the plasma column in a plasma focus discharge

Abstract

Experiments were carried out on the PF-1000 plasma focus device, with a deuterium filling and with deuterium puffing from a gas-puff nozzle placed on the axis of the anode face. The current was reaching 2 MA. 15 interferometric frames from one shot were recorded with a Nd:YLF laser and a Mach–Zehnder interferometer, with 10–20 ns delay between the frames. As a result, the temporal and spatial distribution of the linear densities and the radial and axial velocities of the moving of plasma in the dense plasma column could be estimated.

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Turbulence characteristics of flow in an open channel with temporally varying mobile bedforms

Abstract

Turbulence of flow over mobile bedforms in natural open channels is not yet clearly understood. An attempt is made in this paper to determine the effect of naturally formed mobile bedforms on velocities, turbulent intensities and turbulent stresses. Instantaneous velocities are measured using a two-dimensional particle image velocimetry (PIV) to evaluate the turbulence structure of free surface flow over a fixed (immobile) bed, a weakly mobile bed and a temporally varying mobile bed with different stages of bedform development. This paper documents the vertical distribution of velocity, turbulence intensities, Reynolds shear stress and higher-order moments including skewness and turbulent diffusion factors. Analysis of the velocity distributions shows a substantial decrease of velocity near the bed with increasing bedform mobility due to increased friction. A modified logarithmic law with a reduced von Kármán constant and increased velocity shift is proposed for the case of the mobile bedforms. A significant increase in the Reynolds shear stress is observed in the mobile bedforms experiments accompanied by changes over the entire flow depth compared to an immobile bed. The skewness factor distribution was found to be different in the case of the flow over the mobile bedforms. All higher-order turbulence descriptors are found to be significantly affected by the formation of temporally varying and non-equilibrium mobile bedforms. Quadrant analysis indicates that sweep and outward events are found to be dominant in strongly mobile bedforms and govern the bedform mobility.

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Temporal water table changes in soil toposequence of the Poznań Lakeland (western Poland)

Abstract

The paper presents results of determination of temporal changes in water table depths in the toposequence of Retisols/Luvisols and Phaeozems/Gleysols. Assessment of temporal trends in the water table depth was made with the use of the linear regression analysis. The results obtained indicate that the mean water table depth and mean high and low water table depths were deeper in the soil at the upper part of the slope in comparison with soil located at the footslope. A higher amplitude of water table was observed in Retisols than in Gleysols but the highest variability of water table level was noted in the soils at the footslope compared to those at the slope summit. In Retisols, with each month of observation from 1993 to 2012, the water table showed a tendency to increase. These trends were the highest from January to April, which may be related to the tendency of increasing monthly sums of precipitation in December, January and February. In the Gleysol at the footslope, in the period 1993–2012 and in the vegetation season, the water table depth showed a tendency to decrease. This trend may be due to the impact of water table on the soil water content at the root zone, which is used in the process of evapotranspiration.

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Economic Development And Transfrontier Shipments Of Waste In Poland – Spatio-Temporal Analysis

Abstract

The aim of the paper is to apply the spatio-temporal Environmental Kuznets Curve (SpEKC) to test the relationship between economic growth and the amount of collected mixed municipal waste. The analysis was conducted at the level of sixty-six Polish sub-regions. The study contained selected environmental indicators. The dependent variable - the amount of municipal waste generated in kilograms per capita characterized the state of the environment. The GDP per capita in constant prices (as an explanatory variable) presented the level of economic development of the sub-regions. In the empirical part of the research there were used spatial panel data models based on EKCs. It determined the levels of economic development, at which the amount of produced wastes has fallen or increased, depending on the wealth of the region. The application of different types of spatial weight matrices was an important element of this modelling. Data obtained the years 2005-2012. Models were estimated in the RCran package.

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Spatial temporal variability of maximum flow in Slănic, Teleajen and Prahova River Basins

Abstract

The present study analyzes the spatial temporal variation of maximum flow in Slănic Teleajen and Prahova river basins (upper basin). Maximum flow rates were analyzed in relation to the threshold values corresponding to the Defence Levels respectively the maximum flow which determines exceeding Warning and Flooding Levels. The series of major floods events, selected on the basis of the threshold values mentioned above, were then statistically analyzed to determine trends (Mann-Kendall test) and the variations in the level of frequency, analysis which was applied seasonally and annually. The analysis made revealed that trends in terms of maximum flow rates in the Prahova upper basin were generally negative (decreasing), statistically significant for the February, May, July, August and the annual average, while in Slanic river basin, the trend was mostly positive, statistically significant for October.

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On the Spatio-Temporal Approaches Towards Conservation of Extensively Managed Rural Landscapes in Central-Eastern Europe

Abstract

Land-use change is one of the major drivers of global biodiversity loss, its study experiencing continuous development and increasing recognition, influencing main research directions within ecology. Many studies target the negative aspect; however, the modification of the natural environment over centuries and millennia led to the biodiversity, in its broadest sense, we are trying to conserve nowadays within cultural landscapes. This theoretical paper deals with the issue of spatial and temporal variations in extensively managed rural landscapes from Central-Eastern Europe. The constraints of the state of the art and arising challenges for biodiversity management in complex, farmed landscapes of high nature conservation value are discussed, through the example of Transylvania (Romania). The paper argues for the necessity of considering historical perspectives and traditional knowledge in an attempt to understand the current on-site conditions and developing realistic adaptive management strategies with special emphasis on the (traditional) rural communities, representing a key resource for biodiversity conservation

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The Use of the Temporal Oscillation Model to Assess Variability of Precipitation

Abstract

The article presents the variability of precipitation based on the temporal oscillation model. Series of monthly precipitation totals from the years 1955-1980 were used for the analysis. The detailed research referred to the selected 10 measurement stations in central Poland and 17 in southern Poland. Data series from all the measurement stations were verified in terms of their statistical homogeneity. Furthermore, in accordance with the model guidelines, the tendency was assessed. This was followed by calculation of seasonal and accidental oscillations of precipitation. The results were used to present the variability of precipitation in the two areas studied. The measurement stations in southern Poland showed a much higher mean variation of seasonal oscillations of monthly precipitation. Accidental precipitation, however, is much more significant for the total variability of precipitation in southern Poland.

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Technology Roadmaps, Innovation Journeys, and Nanoworld: A Spatio-temporal Consolidation of the EC Nanotechnology Policy

Abstract

Technology roadmaps have become an essential part of the European Commission’s (EC) nanotechnology policy strategies. They represent socio-technical landscapes and evolving pathways, suggesting the underlying or otherwise supportive metaphorical patterns and narrative structures. For the same reason, however, roadmaps are problematic assemblages: they can simplify and distort reality, and filter things that don’t fit. The presented study combines cognitive linguistics with narratology to scrutinise the European Commission’s nanotechnology roadmapping as a discursive formation. It targets the systematic metaphors in approximately two-hundred news and reports on nanotechnology, compiled ad hoc from the CORDIS database (between the years 1999–2015). It is argued that the identified metaphors correspond to a discourse topology of ‘locations’, ‘events’, and their structures, especially as regards to the dilemma of ‘path dependence’, overcoming ‘knowledge gaps’, and reaching ‘nanoworld’. These are accompanied by a narrative climax of developing mature science policy model, in the arrangement of actions and roles for the European governments, science (nanotechnology), policy, and the public. The study demonstrates how systematic metaphors engage all the actors in the narrative of ‘innovation journey’ to form stabilised structures of meaning, that is, spatio-temporal consolidation of nanotechnology policy. It is imperative to continuously assess the context of such consolidation, being less overt but not necessarily less effective, in privileging some meanings, interests, and practices over the others, thereby excluding other political alternatives.

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