3,884 research outputs found

    CryptoKnight:generating and modelling compiled cryptographic primitives

    Get PDF
    Cryptovirological augmentations present an immediate, incomparable threat. Over the last decade, the substantial proliferation of crypto-ransomware has had widespread consequences for consumers and organisations alike. Established preventive measures perform well, however, the problem has not ceased. Reverse engineering potentially malicious software is a cumbersome task due to platform eccentricities and obfuscated transmutation mechanisms, hence requiring smarter, more efficient detection strategies. The following manuscript presents a novel approach for the classification of cryptographic primitives in compiled binary executables using deep learning. The model blueprint, a Dynamic Convolutional Neural Network (DCNN), is fittingly configured to learn from variable-length control flow diagnostics output from a dynamic trace. To rival the size and variability of equivalent datasets, and to adequately train our model without risking adverse exposure, a methodology for the procedural generation of synthetic cryptographic binaries is defined, using core primitives from OpenSSL with multivariate obfuscation, to draw a vastly scalable distribution. The library, CryptoKnight, rendered an algorithmic pool of AES, RC4, Blowfish, MD5 and RSA to synthesise combinable variants which automatically fed into its core model. Converging at 96% accuracy, CryptoKnight was successfully able to classify the sample pool with minimal loss and correctly identified the algorithm in a real-world crypto-ransomware applicatio

    Time to failure prediction in rubber components subjected to thermal ageing: A combined approach based upon the intrinsic defect concept and the fracture mechanics

    Get PDF
    In this contribution, we attempt to derive a tool allowing the prediction of the stretch ratioat failure in rubber components subjected to thermal ageing. To achieve this goal, the mainidea is to combine the fracture mechanics approach and the intrinsic defect concept. Using an accelerated ageing procedure for an Ethylene–Propylene–Diene Monomer (EPDM), it is first shown that the average molar mass of the elastically active chains (i.e. between crosslinks) can be used as the main indicator of the macromolecular network degradation. Byintroducing the time–temperature equivalence principle, a shift factor obeying to an Arrhenius law is derived, and master curves are built as well for the average molar mass as for the ultimate mechanical properties. Fracture mechanics tests are also achieved and the square root dependence of the fracture energy with the average molar mass is pointed out. Moreover, it is shown that the mechanical response could be approximated by the phantom network theory, which allows to relate the strain energy density function to the average molar mass. Assuming that the fracture of a smooth specimen is the consequence of a virtual intrinsic defect whose the size can be easily estimated, the stretch ratio at break can be therefore computed for any thermal ageing condition. The estimated values are found in a very nice agreement with EPDM experimental data, making this approach a useful tool when designing rubber components for moderate to high temperature environments

    Capital Mobility in Neoclassical Models of Growth

    Get PDF

    Influence of Molecular Organization on the Electrical Characteristics of {\pi}-conjugated Self-assembled Monolayers

    Get PDF
    Two new thiol compounds with {\sigma}-{\pi}-{\sigma} structure were synthesized and self-assembled on gold substrates. The morphology and the structural characterization of SAMs assessed by infrared spectroscopy, contact angle, XPS, electrochemistry and scanning tunneling microscopy (STM) show the formation of monolayers. SAMs with a terthiophene (3TSH) core as conjugated system are much better organized compared to those with a naphthalene carbodiimide (NaphSH) core as demonstrated by the cyclic voltammetry and STM studies. The surface concentration of 3TSH and NaphSH is respectively three and six times lower than ordered SAMs of pure alkyl chains. A large number of I/V characteristics have been studied either by STS measurements on gold substrates or by C-AFM on gold nanodots. Transition Voltage Spectroscopy (TVS) was used to clearly identify the transport in these partially organized monolayers. The chemical nature of the conjugated system, donor for 3TSH and acceptor for NaphSH, involves an opposite rectification associated to the asymmetrical coupling of the molecular orbitals and the electrodes. The conductance histograms show that the 3TSH junctions are less dispersed than those of NaphSH junctions. This is explained by a better control of the molecular organization in the molecular junctions.Comment: Full paper with supporting informatio

    IrcamCorpusTools: an Extensible Platform for Spoken Corpora Exploitation

    Get PDF
    Corpus based methods are increasingly used for speech technology applications and for the development of theoretical or computer models of spoken languages. These usages range from unit selection speech synthesis [1] to statistical modeling of speech phenomena like prosody or expressivity [2]. In all cases, these usages require a wide range of tools for corpus creation, labeling

    Using evaluation techniques and performance claims to demonstrate public relations impact: An Australian perspective

    Get PDF
    Public relations professionals use many methods to demonstrate their contribution to organizational goals, yet it is unclear how their attitudes towards evaluation and the reporting of success matches real outcomes. Ten years after the International Public Relations Association produced an evaluation gold paper, this study combines research on Australian practitioners’ evaluation practices and attitudes, and data from industry awards to identify how practitioners demonstrate their accountability. Data suggest that despite the attention paid to evaluation by the academy and industry, practitioners still focus on measuring outputs, not outcomes to demonstrate performance and continue to rely heavily on media-based evaluation methods

    De-Confinement in high multiplicity proton-proton collisions at LHC energies

    Full text link
    Recently, the CMS Collaboration has published identified particle transverse momentum spectra in high multiplicity events at LHC energies s\sqrt s = 0.9-13 TeV. In the present work the transverse momentum spectra have been analyzed in the framework of the color fields inside the clusters of overlapping strings, which are produced in high energy hadronic collisions. The non-Abelian nature is reflected in the coherence sum of the color fields which as a consequence gives rise to an enhancement of the transverse momentum and a suppression of the multiplicities relative to the non overlapping strings. The initial temperature and shear viscosity to entropy density ratio η/s\eta/s are obtained. For the higher multiplicity events at s\sqrt s =7 and 13 TeV the initial temperature is above the universal hadronization temperature and is consistent with the creation of de-confined matter. In these small systems it can be argued that the thermalization is a consequence of the quantum tunneling through the event horizon introduced by the confining color fields, in analogy to the Hawking-Unruh effect. The small shear viscosity to entropy density ratio η/s\eta/s near the critical temperature suggests that the matter is a strongly coupled Quark Gluon Plasma.Comment: 5 pages, 4 figure
    • 

    corecore