A5013201648- Advanced Algebra and Logic
- Meteorological Phenomena and Simulations
- semigroups and automata theory
- Advanced Topology and Set Theory
- Advanced Graph Theory Research
- Precipitation Measurement and Analysis
- Computational Physics and Python Applications
- Hydrological Forecasting Using AI
- Stochastic processes and statistical mechanics
- Mathematical Dynamics and Fractals
- Climate variability and models
- Tropical and Extratropical Cyclones Research
- GNSS positioning and interference
- Hydrology and Watershed Management Studies
- Energy Load and Power Forecasting
- Cellular Automata and Applications
- Forecasting Techniques and Applications
- Earthquake Detection and Analysis
- Graph theory and applications
- Hydrology and Drought Analysis
- Logic, programming, and type systems
- Ionosphere and magnetosphere dynamics
- Fuzzy and Soft Set Theory
- Graph Labeling and Dimension Problems
- Logic, Reasoning, and Knowledge
Bureau of Meteorology
2022-2024
La Trobe University
2005-2012
Abstract Enhanced interaction between solar‐wind and Earth's magnetosphere can cause space weather geomagnetic storms that have the potential to damage critical technologies, such as magnetic navigation, radio communications, power grids. The severity of a storm is measured using disturbance‐storm‐time ( Dst ) index. index calculated by averaging horizontal component field observed at four near‐equatorial observatories used drive disturbance models. As key specification magnetospheric...
Spacing subshifts were introducedby Lau and Zame in 1973 to provide accessible examples of maps that are (topologically) weakly mixing but not mixing. Although they show a rich variety dynamical characteristics, have received little subsequent attention the systems literature. This paper is systematic study their properties shows may be used with huge range interesting behaviors. In later we propose consider more detail case when spacing also sofic transitive.
Abstract Clark et al. [‘The axiomatizability of topological prevarieties’, Adv. Math. 218 (2008), 1604–1653] have shown that, for k ≥2, there exists a Boolean graph that is -colourable but not topologically -colourable; is, every ϵ>0, it cannot be coloured by paintbrush width ϵ. We generalize this result to show 2-colourable -colourable. This an inverse limit finite graphs which are exist Erdős-style probabilistic argument Hell and Nešetřil core graph’, Discrete 109 (1992), 117–126]. use...
In section 1, we correct an error in the proof of Lemma 3.1 L. Alsedà, M.A. del Río, and J.A. Rodríguez. Transitivity dense periodicity for graph maps. J. Difference Equ. Appl. 9, 577–598, 2003. 2 give a simple that weak mixing implies maps on topological graphs. The proofs can also be extended to (not necessarily compact) intervals, so particular, this paper shows one-dimensional manifolds, mixing.
Statistical post-processing of numerical weather prediction (NWP) guidance is a crucial element the forecast value chain, enabling provision reliable forecast-ready tailored to needs users.   For over decade, Bureau Meteorology has relied on its own Gridded Operational Consensus Forecast (GOCF) system provide calibrated, consensus-based from mix ensemble and deterministic input models. While GOCF been instrumental in enhancing skill Bureau's forecasts supporting increased...
We introduce Neighbourhood Ensemble Copula Coupling, a technique for post-processing ensemble precipitation forecasts to produce physically realistic, well-calibrated scenarios.Modern forecasting typically uses produced by numerical weather prediction (NWP) models. These ensembles aim represent the range of probable outcomes, and enable us derive probabilistic predictions (for example, we may predict 20% chance at least 10 mm rainfall particular location). Because NWP models employ...
We examine a universal algebraic abstraction of the semigroup theoretic concept "divides:" divides b in an algebra A if for some n ∈ ω, there is term t(x, y 1,…, ) involving all listed variables, and elements c such that t (a, = b. The first order definability this relation shown to be very broad generalisation familiar congruence properties, as principal congruences. algorithmic problem deciding when finitely generated variety has definable equivalent open concerning flat algebras. also use...
Accurate rainfall forecasting is vital for public safety, yet precipitation remains one of the most challenging variables to predict. While development ensemble Numerical Weather Prediction (NWP) models enables kind probabilistic that so much more descriptive characteristics than simple deterministic forecasts, accurate and efficient calibration ensembles presents its own challenges. Rainfall’s skewed distribution discontinuous nature in both time space, importance impact extreme...
Abstract Ensemble copula coupling (Schefzik et al.) is a widely used method to produce calibrated ensemble from probabilistic forecast. This process improves the statistical accuracy of ensemble; in other words, distribution members at each grid point more closely approximates true expected distribution. However, trade-off that individual are often less physically realistic than original ensemble: there noisy variation among neighboring points, and, depending on calibration method, extremes...
Abstract Probabilistic forecasts derived from ensemble prediction systems (EPS) have become the standard basis for many products and services produced by modern operational forecasting centres. However statistical post-processing is generally required to ensure desired properties expected probability-based outputs. Precipitation, a core component of any forecast, particularly challenging calibrate due its discontinuous nature extreme skew in rainfall amounts. A skillful system must maintain...
Abstract Operational forecasting systems often combine calibrated probabilistic outputs from several numerical weather prediction (NWP) models. A common approach is to use a weighted blend, with the more accurate models having higher weights. We show that this not ideal and using simple neural network forecasts yields better results. The sharpness of forecast increased, so extreme events are likely be predicted. Improvements also observed in accuracy as measured by continuous rank...
The graph of an algebra A is the relational structure G(A) in which relations are graphs basic operations A. For a class 𝒞 algebras let G(𝒞)={G(A)∣A∈𝒞}. Assume that semigroups possessing nontrivial member with neutral element and ℋ be universal Horn generated by G(𝒞). We prove Boolean core ℋ, i.e., topological prevariety finite members equipped discrete topology, does not admit first-order axiomatization relative to all structures language ℋ. derive analogous results when monoids or groups member.
<p>Improvements to skill (and other characteristics) of quantitative probabilistic rainfall forecasting for weather and hydrological purposes are a high priority at the Australian Bureau Meteorology (the Bureau), highlighted by series major floods in eastern Australia early 2022.  Post-processed ensemble numerical prediction (NWP) guidance is key increasing forecast automation routine conditions providing better impact...