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Entropy analysis of energy price movement

100%

Kapica J.

Teka Komisji Motoryzacji i Energetyki Rolnictwa

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2012

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tom 12

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nr 2

2

Body size and the relative abundance of species

84%

Ulrich W.

Ecological Questions

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2008

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tom 10

Existing models of species abundance distributions (SADs) can be divided into those that are based on concepts of common limited niche space (niche apportionment models, neutral models) and those that invoke standard statistical distributions (e. g. log-series, lognormal). While the first type of models assumes that competitive interactions lead to observed SADs, the models of the second type appear to be mainly statistical descriptors of SADs without deeper biological meaning. None of the models explicitly includes species body size as a factor influencing species abundances. Further, with the exception of recent neutral models they are not embedded into basic ecological and evolutionary models to explain local diversity and ecosystem functioning. Here I present a new random walk model of species abundances that is based on two well known ecological distributions, the abundance - body weight distribution and the species - body weight distribution to define long-term upper abundance boundaries (carrying capacities). I show that a simple random walk of species abundances around the carrying capacities not only generates observed SADs but is also able to explain other patterns of community structure like core - satellite distributions, temporal patterns of species turnover, variance - mean ratios, and biomass distributions.

3

Calibration of backward-in-time model using drifting buoys in the East China Sea

84%

Yu F., Li J., Zhao Y., Li Q., Chen G.

Oceanologia

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2017

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tom 59

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nr 3

In the process of oil exploitation and transportation, large amounts of crude oil are often spilled, resulting in serious pollution of the marine environment. Forecasting oil spill reverse trajectories to determine the exact oil spill sources is crucial for taking proactive and effective emergency measures. In this study, the backward-in-time model (BTM) is proposed for identifying sources of oil spills in the East China Sea. The wind, current and random walk are three major factors in the simulation of oil spill sources. The wind drag coefficient varies along with the uncertainty of the wind field, and the random walk is sensitive to various traits of different regions, these factors are taken as constants in most of the state-of-the-art studies. In this paper, a self-adaptive modification mechanism for drift factors is proposed, which depends on a data set derived from the drifter buoys deployed over the East China Sea shelf. It can be well adapted to the regional characteristics of different sea areas. The correlation factor between predicted positions and actual locations of the drifters is used to estimate optimal coefficients of the BTM. A comparison between the BTM and the traditional method is also made in this study. The results presented in this paper indicate that our method can be used to predict the actual specific spillage locations.

4

Local and global description of transport through membranes

84%

Grzywna Z. J.

Biophysics of Membrane Transport

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1992

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tom 11

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nr 1

Ograniczanie wyników

1 Biophysics of Membrane Transport

1 Ecological Questions

1 Oceanologia

1 Teka Komisji Motoryzacji i Energetyki Rolnictwa

1 Chen G.

1 Grzywna Z. J.

1 Kapica J.

1 Li J.

1 Li Q.

1 Ulrich W.

1 Yu F.

1 Zhao Y.

1 2017

1 2012

1 2008

1 1992

Entropy analysis of energy price movement

Body size and the relative abundance of species

Calibration of backward-in-time model using drifting buoys in the East China Sea

Local and global description of transport through membranes