Self-organized criticality has been proposed to explain complex dynamical systems near their critical points. This experiment examined a monodisperse conical bead pile and how the distribution of avalanches is affected by the pattern of beads glued on a base, by the size or shape of the base, and by the height at which each bead was dropped onto the pile. By measuring the number of avalanches for a given size that occurred during the experiment, the resulting distribution could be compared to a power law description. When the beads were dropped from a small height, all data were consistent with a simple power law of exponent -1.5, which is the mean-field model value. The data showed that neither the bead pattern on the base nor the base size or shape significantly affected the power law behavior. However, when the bead is dropped from different heights, then the power law description breaks down and a power law times an exponential is more appropriate. We found a scaling relationship in the distribution of avalanches for different heights and relate the data to an energy dissipation model. We both confirm self-organized criticality and observe deviations from it.
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http://dx.doi.org/10.1103/PhysRevE.67.041304 | DOI Listing |
PLoS One
January 2025
Business School, Huaqiao University, Quanzhou, Fujian, China.
Global climate change has become one of the most large-scale, widespread, and far-reaching challenges facing mankind. Against this background, China has proposed a "dual-carbon" target in 2020, which greatly demonstrates China's determination and commitment to carbon emission reduction, and the burden of realizing the "dual-carbon" target is mainly borne by heavy polluters. The burden of achieving the "dual-carbon" goal is mainly borne by the heavily polluting firms.
View Article and Find Full Text PDFGenet Epidemiol
January 2025
Interdisciplinary Program of Bioinformatics, College of Natural Science, Seoul National University, Seoul, South Korea.
In this article, we proposed a new method named fused mixed graphical model (FMGM), which can infer network structures associated with dichotomous phenotypes. FMGM is based on a pairwise Markov random field model, and statistical analyses including the proposed method were conducted to find biological markers and underlying network structures of the atopic dermatitis (AD) from multiomics data of 6-month-old infants. The performance of FMGM was evaluated with simulations by using synthetic datasets of power-law networks, showing that FMGM had superior performance for identifying the differences of the networks compared to the separate inference with the previous method, causalMGM (F1-scores 0.
View Article and Find Full Text PDFSci Rep
January 2025
School of City and Architecture Engineering, Zaozhuang University, Zaozhuang, 277160, Shandong, China.
To study the enhancement effect of carbon nanotubes (CNTs) on the splitting tensile properties of foamed concrete backfill in which cement and fly ash were used as the cementitious materials and natural sand was used as the aggregate, specimens of CNT-modified foamed concrete backfill were prepared. Brazilian splitting tests were used to investigate the splitting tensile strength of the CNT-modified foamed concrete backfill, and the digital speckle correlation method was used to analyze the stress field characteristics and crack expansion law of the specimens during splitting tensile testing. The stress-strain characteristics and energy dissipation laws of the backfill were studied at various static loading rates, and a relationship between the splitting tensile strength, ultimate strain, and loading rate was established.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
China Three Gorges Corporation, Beijing 100038, China.
With the rapid decline in the levelized cost, offshore wind power offers a new option for the clean energy transition of the power sector in China's coastal areas. Here, we develop a power system capacity expansion and operation optimization model to simulate the penetration of offshore wind power in China and quantify the associated health effects. We find that offshore wind power has great potential in mitigating the negative impacts of existing coal-fired power emissions.
View Article and Find Full Text PDFInternet Interv
March 2025
Department of Public Health, University Of Copenhagen, Øster Farimagsgade 5, 1353 København K, Denmark.
Parental relationship dissolution is among the most prevalent life crises for youths and is associated with both short- and long-term intra- and interpersonal struggles. Extant support programs tend to be in-person and in a group format. However, the structure and personnel needed for these programs make them costly to implement, less accessible, and difficult to scale.
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