2,586 research outputs found

    Malware Detection Using Dynamic Analysis

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    In this research, we explore the field of dynamic analysis which has shown promis- ing results in the field of malware detection. Here, we extract dynamic software birth- marks during malware execution and apply machine learning based detection tech- niques to the resulting feature set. Specifically, we consider Hidden Markov Models and Profile Hidden Markov Models. To determine the effectiveness of this dynamic analysis approach, we compare our detection results to the results obtained by using static analysis. We show that in some cases, significantly stronger results can be obtained using our dynamic approach

    Combining Dynamic and Static Analysis for Malware Detection

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    Well-designed malware can evade static detection techniques, such as signature scanning. Dynamic analysis strips away one layer of obfuscation and hence such an approach can potentially provide more accurate detection results. However, dynamic analysis is generally more costly than static analysis. In this research, we analyze the effectiveness of using dynamic analysis to enhance the training phase, while using only static techniques in the detection phase. Relative to a fully static approach, the additional overhead is minimal, since training is essentially one-time work

    Zircon ages in granulite facies rocks: decoupling from geochemistry above 850 °C?

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    Granulite facies rocks frequently show a large spread in their zircon ages, the interpretation of which raises questions: Has the isotopic system been disturbed? By what process(es) and conditions did the alteration occur? Can the dates be regarded as real ages, reflecting several growth episodes? Furthermore, under some circumstances of (ultra-)high-temperature metamorphism, decoupling of zircon U–Pb dates from their trace element geochemistry has been reported. Understanding these processes is crucial to help interpret such dates in the context of the P–T history. Our study presents evidence for decoupling in zircon from the highest grade metapelites (> 850 °C) taken along a continuous high-temperature metamorphic field gradient in the Ivrea Zone (NW Italy). These rocks represent a well-characterised segment of Permian lower continental crust with a protracted high-temperature history. Cathodoluminescence images reveal that zircons in the mid-amphibolite facies preserve mainly detrital cores with narrow overgrowths. In the upper amphibolite and granulite facies, preserved detrital cores decrease and metamorphic zircon increases in quantity. Across all samples we document a sequence of four rim generations based on textures. U–Pb dates, Th/U ratios and Ti-in-zircon concentrations show an essentially continuous evolution with increasing metamorphic grade, except in the samples from the granulite facies, which display significant scatter in age and chemistry. We associate the observed decoupling of zircon systematics in high-grade non-metamict zircon with disturbance processes related to differences in behaviour of non-formula elements (i.e. Pb, Th, U, Ti) at high-temperature conditions, notably differences in compatibility within the crystal structure

    Workshop on Early Crustal Genesis: Implications from Earth

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    Ways to foster increased study of the early evolution of the Earth, considering the planet as a whole, were explored and recommendations were made to NASA with the intent of exploring optimal ways for integrating Archean studies with problems of planetary evolution. Major themes addressed include: (1) Archean contribution to constraints for modeling planetary evolution; (2) Archean surface conditions and processes as clues to early planetary history; and (3) Archean evidence for physical, chemical and isotopic transfer processes in early planetary crusts. Ten early crustal evolution problems are outlined

    Detecting the oldest geodynamo and attendant shielding from the solar wind: Implications for habitability

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    The onset and nature of the earliest geomagnetic field is important for understanding the evolution of the core, atmosphere and life on Earth. A record of the early geodynamo is preserved in ancient silicate crystals containing minute magnetic inclusions. These data indicate the presence of a geodynamo during the Paleoarchean, between 3.4 and 3.45 billion years ago. While the magnetic field sheltered Earth's atmosphere from erosion at this time, standoff of the solar wind was greatly reduced, and similar to that during modern extreme solar storms. These conditions suggest that intense radiation from the young Sun may have modified the atmosphere of the young Earth by promoting loss of volatiles, including water. Such effects would have been more pronounced if the field were absent or very weak prior to 3.45 billion years ago, as suggested by some models of lower mantle evolution. The frontier is thus trying to obtain geomagnetic field records that are >>3.45 billion-years-old, as well as constraining solar wind pressure for these times. In this review we suggest pathways for constraining these parameters and the attendant history of Earth's deep interior, hydrosphere and atmosphere. In particular, we discuss new estimates for solar wind pressure for the first 700 million years of Earth history, the competing effects of magnetic shielding versus solar ion collection, and bounds on the detection level of a geodynamo imposed by the presence of external fields. We also discuss the prospects for constraining Hadean-Paleoarchean magnetic field strength using paleointensity analyses of zircons.Comment: 78 pages, 8 figures, Supplementary Content: Reconstructing the Past Sun + table of solar parameters from ZAMS to present through geological tim

    A secular increase in continental crust nitrogen during the Precambrian

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    Recent work indicates the presence of substantial geologic nitrogen reservoirs in the mantle and continental crust. Importantly, this geologic nitrogen has exchanged between the atmosphere and the solid Earth over time. Changes in atmospheric nitrogen (i.e. atmospheric mass) have direct effects on climate and biological productivity. It is difficult to constrain, however, the evolution of the major nitrogen reservoirs through time. Here we show a secular increase in continental crust nitrogen through Earth history recorded in glacial tills (2.9 Ga to modern), which act as a proxy for average upper continental crust composition. Archean and earliest Palaeoproterozoic tills contain 66 ±\pm 100 ppm nitrogen, whereas Neoproterozoic and Phanerozoic tills contain 290 ±\pm 165 ppm nitrogen, whilst the isotopic composition has remained constant at ~4\permil. Nitrogen has accumulated in the continental crust through time, likely sequestered from the atmosphere via biological fixation. Our findings support dynamic, non-steady state behaviour of nitrogen through time, and are consistent with net transfer of atmospheric N to geologic reservoirs over time.Comment: 14 pages, 2 figures, 2 tables, supplemental informatio

    Program & Abstracts, 6th Annual Research Day (2019)

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    Program and abstracts from the Faculty of Science and Technology 6th Annual Research Day (2019). The research presented here encompasses both independent research projects and research in the classroom. In this volume you will find 82 abstracts authored by MRU students covering with a variety of disciplines including Biology, Chemistry, Geology, Geography, Environmental Sciences, Mathematics, Physics, and Computer Science. This compilation is a testimony to our students’ hard work, and their professors’ diligent guidance

    Malware Detection using the Index of Coincidence

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    In this research, we apply the Index of Coincidence (IC) to problems in malware analysis. The IC, which is often used in cryptanalysis of classic ciphers, is a technique for measuring the repeat rate in a string of symbols. A score based on the IC is applied to a variety of challenging malware families. We nd that this relatively simple IC score performs surprisingly well, with superior results in comparison to various machine learning based scores, at least in some cases
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