20,058 research outputs found

    EviPlant: An efficient digital forensic challenge creation, manipulation and distribution solution

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    Education and training in digital forensics requires a variety of suitable challenge corpora containing realistic features including regular wear-and-tear, background noise, and the actual digital traces to be discovered during investigation. Typically, the creation of these challenges requires overly arduous effort on the part of the educator to ensure their viability. Once created, the challenge image needs to be stored and distributed to a class for practical training. This storage and distribution step requires significant time and resources and may not even be possible in an online/distance learning scenario due to the data sizes involved. As part of this paper, we introduce a more capable methodology and system as an alternative to current approaches. EviPlant is a system designed for the efficient creation, manipulation, storage and distribution of challenges for digital forensics education and training. The system relies on the initial distribution of base disk images, i.e., images containing solely base operating systems. In order to create challenges for students, educators can boot the base system, emulate the desired activity and perform a "diffing" of resultant image and the base image. This diffing process extracts the modified artefacts and associated metadata and stores them in an "evidence package". Evidence packages can be created for different personae, different wear-and-tear, different emulated crimes, etc., and multiple evidence packages can be distributed to students and integrated into the base images. A number of additional applications in digital forensic challenge creation for tool testing and validation, proficiency testing, and malware analysis are also discussed as a result of using EviPlant.Comment: Digital Forensic Research Workshop Europe 201

    Local Geography of Row-Crop Quality Land and Cropland Cash Rental Rates

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    While farmland rental markets are likely to be spatially differentiated, the fine spatial structure of row-crop quality land should have a significant effect on cash rent determination. This study provides a rigorous empirical understanding of the effect of land spatial heterogeneity on cash rental rates. The lacunarity index is employed to measure spatial heterogeneity of land quality, which is built directly upon a soil quality measure, the land parcel’s corn suitability rating index (CSR). A panel data random effect model is applied on annual survey data of farmland cash rental rates of Iowa for 1987-2009. As expected, land spatial heterogeneity has a statistically significant and negative effect on local cash rent rates. The effect’s origin warrants further research.land spatial heterogeneity, rental market, Agricultural Finance, C5, G1, Q1,

    Tidal disruption of fuzzy dark matter subhalo cores

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    We study tidal stripping of fuzzy dark matter (FDM) subhalo cores using simulations of the Schr\"{o}dinger-Poisson equations and analyze the dynamics of tidal disruption, highlighting the differences with standard cold dark matter. Mass loss outside of the tidal radius forces the core to relax into a less compact configuration, lowering the tidal radius. As the characteristic radius of a solitonic core scales inversely with its mass, tidal stripping results in a runaway effect and rapid tidal disruption of the core once its central density drops below 4.54.5 times the average density of the host within the orbital radius. Additionally, we find that the core is deformed into a tidally locked ellipsoid with increasing eccentricities until it is completely disrupted. Using the core mass loss rate, we compute the minimum mass of cores that can survive several orbits for different FDM particle masses and compare it with observed masses of satellite galaxies in the Milky Way.Comment: 11 pages, 12 figures, accepted for publication in PR

    Tunable Semiconductors: Control over Carrier States and Excitations in Layered Hybrid Organic-Inorganic Perovskites

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    For a class of 2D hybrid organic-inorganic perovskite semiconductors based on π\pi-conjugated organic cations, we predict quantitatively how varying the organic and inorganic component allows control over the nature, energy and localization of carrier states in a quantum-well-like fashion. Our first-principles predictions, based on large-scale hybrid density-functional theory with spin-orbit coupling, show that the interface between the organic and inorganic parts within a single hybrid can be modulated systematically, enabling us to select between different type-I and type-II energy level alignments. Energy levels, recombination properties and transport behavior of electrons and holes thus become tunable by choosing specific organic functionalizations and juxtaposing them with suitable inorganic components
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