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All Outputs (181)

On the abundance of extreme voids (2015)
Journal Article
Chongchitnan, S. (2015). On the abundance of extreme voids. Journal of cosmology and astroparticle physics, May(05), 062-062. https://doi.org/10.1088/1475-7516/2015/05/062

Cosmic voids have been shown to be an effective probe of cosmology, complementary to galaxy clusters. In this work, we present a simple theoretical framework for predicting of the size of the largest voids expected within a given redshift and volume.... Read More about On the abundance of extreme voids.

Elementary modelling and behavioural analysis for emergency evacuations using social media (2015)
Journal Article
Fry, J., & Binner, J. (2016). Elementary modelling and behavioural analysis for emergency evacuations using social media. European journal of operational research, 249(3), 1014-1023. https://doi.org/10.1016/j.ejor.2015.05.049

Social media usage in evacuations and emergency management represents a rapidly expanding field of study. Our paper thus provides quantitative insight into a serious practical problem. Within this context a behavioural approach is key. We discuss whe... Read More about Elementary modelling and behavioural analysis for emergency evacuations using social media.

Resource-efficient fusion with pre-compensated transmissions for cooperative spectrum sensing (2015)
Journal Article
Cattaneo, M. E., Aquino, G. P., & Guimarães, D. A. (2015). Resource-efficient fusion with pre-compensated transmissions for cooperative spectrum sensing. Sensors, 15(5), 10891-10908. https://doi.org/10.3390/s150510891

© 2015 by the authors; licensee MDPI, Basel, Switzerland. Recently, a novel fusion scheme for cooperative spectrum sensing was proposed for saving resources in the control channel. Secondary users (SUs) simultaneously report their decisions using bin... Read More about Resource-efficient fusion with pre-compensated transmissions for cooperative spectrum sensing.

The commuting graph of the symmetric inverse semigroup (2015)
Journal Article
Araújo, J., Bentz, W., & Janusz, K. (2015). The commuting graph of the symmetric inverse semigroup. Israel journal of mathematics, 207(1), 103-149. https://doi.org/10.1007/s11856-015-1173-9

The commuting graph of a finite non-commutative semigroup S, denoted G(S), is a simple graph whose vertices are the non-central elements of S and two distinct vertices x, y are adjacent if xy = yx. Let I(X) be the symmetric inverse semigroup of parti... Read More about The commuting graph of the symmetric inverse semigroup.

Speculative bubbles in Bitcoin markets? An empirical investigation into the fundamental value of Bitcoin (2015)
Journal Article
Cheah, E., & Fry, J. (2015). Speculative bubbles in Bitcoin markets? An empirical investigation into the fundamental value of Bitcoin. Economics letters, 130, 32-36. https://doi.org/10.1016/j.econlet.2015.02.029

Amid its rapidly increasing usage and immense public interest the subject of Bitcoin has raised profound economic and societal issues. In this paper we undertake economic and econometric modelling of Bitcoin prices. As with many asset classes we show... Read More about Speculative bubbles in Bitcoin markets? An empirical investigation into the fundamental value of Bitcoin.

Stochastic modelling for financial bubbles and policy (2015)
Journal Article
Fry, J. (2015). Stochastic modelling for financial bubbles and policy. Cogent Economics and Finance, 3(1), Article 1002152. https://doi.org/10.1080/23322039.2014.1002152

In this paper, we draw upon the close relationship between statistical physics and mathematical finance to develop a suite of models for financial bubbles and crashes. By modifying previous approaches, we are able to derive novel analytical formulae... Read More about Stochastic modelling for financial bubbles and policy.

On the Gaussian behavior of marginals and the mean width of random polytopes (2015)
Journal Article
Alonso-Gutiérrez, D., & Prochno, J. (2015). On the Gaussian behavior of marginals and the mean width of random polytopes. Proceedings of the American Mathematical Society, 143(2), 821-832. https://doi.org/10.1090/S0002-9939-2014-12401-4

© 2014 American Mathematical Society. We show that the expected value of the mean width of a random polytope generated by N random vectors (n ≤ N ≤ e√n) uniformly distributed in an isotropic convex body in ℝnis of the order√logNLK. This completes a r... Read More about On the Gaussian behavior of marginals and the mean width of random polytopes.

Uniform estimates for averages of order statistics of matrices (2015)
Journal Article
Lechner, R., Passenbrunner, M., & Prochno, J. (2015). Uniform estimates for averages of order statistics of matrices. Electronic Communications in Probability, 20, 1-12. https://doi.org/10.1214/ECP.v20-3992

We prove uniform estimates for the expected value of averages of order statistics of matrices interms of their largest entries. As an application, we obtain similar probabilistic estimates for ℓp norms via real interpolation.

On Mean Outer Radii of Random Polytopes (2014)
Journal Article
Alonso-Gutiérrez, D., Dafnis, N., Cifre, M. Á. H., & Prochno, J. (2014). On Mean Outer Radii of Random Polytopes. Indiana University Mathematics Journal, 63(2), 579-595

In this paper we introduce a new sequence of quantities for random polytopes. Let $K_N=\conv\{X_1,...,X_N\}$ be a random polytope generated by independent random vectors uniformly distributed in an isotropic convex body K of $\R^n$. We prove that the... Read More about On Mean Outer Radii of Random Polytopes.

The passive diffusion of Leptospira interrogans (2014)
Journal Article
Koens, L., & Lauga, E. (2014). The passive diffusion of Leptospira interrogans. Physical Biology, 11(6), Article 066008. https://doi.org/10.1088/1478-3975/11/6/066008

Motivated by recent experimental measurements, the passive diffusion of the bacterium Leptospira interrogans is investigated theoretically. By approximating the cell shape as a straight helix and using the slender-body-theory approximation of Stokesi... Read More about The passive diffusion of Leptospira interrogans.

The Lyman α forest as a tool for disentangling non-Gaussianities (2014)
Journal Article
Chongchitnan, S. (2014). The Lyman α forest as a tool for disentangling non-Gaussianities. Journal of cosmology and astroparticle physics, 2014(10), Article ARTN 034. https://doi.org/10.1088/1475-7516/2014/10/034

© 2014 IOP Publishing Ltd and Sissa Medialab srl . Detection of primordial non-Gaussianity will give us an unprecedented detail of the physics of inflation. As observational probes are now exploring new expanses of the inflationary landscape, it is c... Read More about The Lyman α forest as a tool for disentangling non-Gaussianities.

Algorithms for arithmetic groups with the congruence subgroup property (2014)
Journal Article
Detinko, A. S., Flannery, D. L., & Hulpke, A. (2015). Algorithms for arithmetic groups with the congruence subgroup property. Journal of Algebra, 421, 234-259. https://doi.org/10.1016/j.jalgebra.2014.08.027

© 2014 Elsevier Inc. We develop practical techniques to compute with arithmetic groups H≤SL(n,Q) for n>. 2. Our approach relies on constructing a principal congruence subgroup in H. Problems solved include testing membership in H, analyzing the subno... Read More about Algorithms for arithmetic groups with the congruence subgroup property.

Lattice gerbe theory (2014)
Journal Article
Lipstein, A. E., & Reid-Edwards, R. A. (2014). Lattice gerbe theory. Journal of High Energy Physics, 2014(9), Article ARTN 034. https://doi.org/10.1007/JHEP09%282014%29034

We formulate the theory of a 2-form gauge field on a Euclidean spacetime lattice. In this approach, the fundamental degrees of freedom live on the faces of the lattice, and the action can be constructed from the sum over Wilson surfaces associated wi... Read More about Lattice gerbe theory.

Integrality and arithmeticity of solvable linear groups (2014)
Journal Article
Detinko, A. S., Flannery, D. L., & de Graaf, W. A. (2015). Integrality and arithmeticity of solvable linear groups. Journal of Symbolic Computation, 68(P1), 138-145. https://doi.org/10.1016/j.jsc.2014.08.011

We develop a practical algorithm to decide whether a finitely generated subgroup of a solvable algebraic group G is arithmetic. This incorporates a procedure to compute a generating set of an arithmetic subgroup of G. We also provide a simple new alg... Read More about Integrality and arithmeticity of solvable linear groups.

Quantitative decision-making for the next generation of smarter evacuations (2014)
Book Chapter
Fry, J., Galla, T., & Binner, J. (2014). Quantitative decision-making for the next generation of smarter evacuations. In J. Preston, J. M. Binner, L. Branicki, T. Galla, N. Jones, J. King, …M. Smyrnakis (Eds.), City Evacuations: An Interdisciplinary Approach (63-87). Berlin: Springer. https://doi.org/10.1007/978-3-662-43877-0_4

In this chapter we discuss the mathematical modelling of the next generation of smarter evacuations. Alongside a burgeoning literature on resilience we formulate a quantitative decision-making framework through which Social Media can be used to deliv... Read More about Quantitative decision-making for the next generation of smarter evacuations.

Multivariate bubbles and antibubbles (2014)
Journal Article
Fry, J. (2014). Multivariate bubbles and antibubbles. European Physical Journal B : Condensed Matter and Complex Systems, 87, Article 174. https://doi.org/10.1140/epjb/e2014-50324-9

In this paper we develop models for multivariate financial bubbles and antibubbles based on statistical physics. In particular, we extend a rich set of univariate models to higher dimensions. Changes in market regime can be explicitly shown to repres... Read More about Multivariate bubbles and antibubbles.

On air cushioning in axisymmetric impacts (2014)
Journal Article
Moore, M., & Oliver, J. (2014). On air cushioning in axisymmetric impacts. IMA Journal of Applied Mathematics, 79(4), 661-680. https://doi.org/10.1093/imamat/hxu026

This paper extends the work of Moore et al. (2013, Air-cushioning in impact problems. IMA J. Appl. Math., 78, 818–838) by using a displacement potential formulation to analyse the post-impact effect of an air-cushioning layer on the normal impact of... Read More about On air cushioning in axisymmetric impacts.

The largest subsemilattices of the endomorphism monoid of an independence algebra (2014)
Journal Article
Araújo, J., Bentz, W., & Konieczny, J. (2014). The largest subsemilattices of the endomorphism monoid of an independence algebra. Linear algebra and its applications, 458, 60-79. https://doi.org/10.1016/j.laa.2014.05.041

An algebra A is said to be an independence algebra if it is a matroid algebra and every map α:X→A, defined on a basis X of A, can be extended to an endomorphism of A. These algebras are particularly well-behaved generalizations of vector spaces, and... Read More about The largest subsemilattices of the endomorphism monoid of an independence algebra.