197 research outputs found

    Computing Compliant Anonymisations of Quantified ABoxes w.r.t. EL Policies

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    We adapt existing approaches for privacy-preserving publishing of linked data to a setting where the data are given as Description Logic (DL) ABoxes with possibly anonymised (formally: existentially quantified) individuals and the privacy policies are expressed using sets of concepts of the DL EL. We provide a chacterization of compliance of such ABoxes w.r.t. EL policies, and show how optimal compliant anonymisations of ABoxes that are non-compliant can be computed. This work extends previous work on privacy-preserving ontology publishing, in which a very restricted form of ABoxes, called instance stores, had been considered, but restricts the attention to compliance. The approach developed here can easily be adapted to the problem of computing optimal repairs of quantified ABoxes

    Применение программного продукта Eclipse для оптимизации разработки нефтяных месторождений Западно-Сибирского региона

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    Применение программного продукта Eclipse для оптимизации разработки нефтяных месторождений Западно-Сибирского регионаApplication software Eclipse to optimize the development of oil fields of West Siberi

    Propositional Dynamic Logic with Converse and Repeat for Message-Passing Systems

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    The model checking problem for propositional dynamic logic (PDL) over message sequence charts (MSCs) and communicating finite state machines (CFMs) asks, given a channel bound BB, a PDL formula φ\varphi and a CFM C\mathcal{C}, whether every existentially BB-bounded MSC MM accepted by C\mathcal{C} satisfies φ\varphi. Recently, it was shown that this problem is PSPACE-complete. In the present work, we consider CRPDL over MSCs which is PDL equipped with the operators converse and repeat. The former enables one to walk back and forth within an MSC using a single path expression whereas the latter allows to express that a path expression can be repeated infinitely often. To solve the model checking problem for this logic, we define message sequence chart automata (MSCAs) which are multi-way alternating parity automata walking on MSCs. By exploiting a new concept called concatenation states, we are able to inductively construct, for every CRPDL formula φ\varphi, an MSCA precisely accepting the set of models of φ\varphi. As a result, we obtain that the model checking problem for CRPDL and CFMs is still in PSPACE

    Исследование инкапсуляторов глин на основе полиакриламида для систем буровых растворов

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    Цель работы – исследование влияния соли на полимеры для систем буровых растворов. Объект исследования: синтетическая полимерная система для буровых растворов. В результате исследования сравнивали акрилитный и синтетический тип полимера с использованием различных концентраций соли NaCl.Aim of the work is to study the effect of salt on polymers for drilling fluid systems. Object of study: a synthetic polymer system for drilling fluids. Result of the study: the acrylite and synthetic types of the polymer were compared using different concentrations of NaCl sal

    Public Evidence from Secret Ballots

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    Elections seem simple---aren't they just counting? But they have a unique, challenging combination of security and privacy requirements. The stakes are high; the context is adversarial; the electorate needs to be convinced that the results are correct; and the secrecy of the ballot must be ensured. And they have practical constraints: time is of the essence, and voting systems need to be affordable and maintainable, and usable by voters, election officials, and pollworkers. It is thus not surprising that voting is a rich research area spanning theory, applied cryptography, practical systems analysis, usable security, and statistics. Election integrity involves two key concepts: convincing evidence that outcomes are correct and privacy, which amounts to convincing assurance that there is no evidence about how any given person voted. These are obviously in tension. We examine how current systems walk this tightrope.Comment: To appear in E-Vote-Id '1

    End-to-end verifiable elections in the standard model

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    We present the cryptographic implementation of “DEMOS”, a new e-voting system that is end-to-end verifiable in the standard model, i.e., without any additional “setup” assumption or access to a random oracle (RO). Previously known end-to-end verifiable e-voting systems required such additional assumptions (specifically, either the existence of a “randomness beacon” or were only shown secure in the RO model). In order to analyze our scheme, we also provide a modeling of end-to-end verifiability as well as privacy and receipt-freeness that encompasses previous definitions in the form of two concise attack games. Our scheme satisfies end-to-end verifiability information theoretically in the standard model and privacy/receipt-freeness under a computational assumption (subexponential Decisional Diffie Helman). In our construction, we utilize a number of techniques used for the first time in the context of e-voting schemes that include utilizing randomness from bit-fixing sources, zero-knowledge proofs with imperfect verifier randomness and complexity leveraging

    Электрооборудование и электропривод ротора буровой установки

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    Цель работы - разработка и исследование двухзонного электропривода ротора буровой установки. В работе выбраны элементы силовой цепи, определены оптимальные параметры настройки регуляторов системы, рассчитаны статические и динамические характеристики, определены качественные показатели. В результате исследования установлено, что разработанная система соответствует технологическим и техническим требованиям.The purpose of the work is to develop and study a two-zone electric drive of the drilling rig rotor. In the operation, elements of the power circuit are selected, optimal parameters of system regulators are determined, static and dynamic characteristics are calculated, qualitative indicators are determined. As a result of the study, it was found that the developed system meets the technological and technical requirements

    Analysis of the IBM CCA Security API Protocols in Maude-NPA

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    Standards for cryptographic protocols have long been attractive candidates for formal verification. It is important that such standards be correct, and cryptographic protocols are tricky to design and subject to non-intuitive attacks even when the underlying cryptosystems are secure. Thus a number of general-purpose cryptographic protocol analysis tools have been developed and applied to protocol standards. However, there is one class of standards, security application programming interfaces (security APIs), to which few of these tools have been applied. Instead, most work has concentrated on developing special-purpose tools and algorithms for specific classes of security APIs. However, there can be much advantage gained from having general-purpose tools that could be applied to a wide class of problems, including security APIs. One particular class of APIs that has proven difficult to analyze using general-purpose tools is that involving exclusive-or. In this paper we analyze the IBM 4758 Common Cryptographic Architecture (CCA) protocol using an advanced automated protocol verification tool with full exclusive-or capabilities, the Maude-NPA tool. This is the first time that API protocols have been satisfactorily specified and analyzed in the Maude-NPA, and the first time XOR-based APIs have been specified and analyzed using a general-purpose unbounded session cryptographic protocol verification tool that provides direct support for AC theories. We describe our results and indicate what further research needs to be done to make such protocol analysis generally effective.Antonio González-Burgueño, Sonia Santiago and Santiago Escobar have been partially supported by the EU (FEDER) and the Spanish MINECO under grants TIN 2010-21062-C02-02 and TIN 2013-45732-C4-1-P, and by Generalitat Valenciana PROMETEO2011/052. José Meseguer has been partially supported by NSF Grant CNS 13-10109.González Burgueño, A.; Santiago Pinazo, S.; Escobar Román, S.; Meadows, C.; Meseguer, J. (2014). Analysis of the IBM CCA Security API Protocols in Maude-NPA. En Security Standardisation Research. Springer International Publishing. 111-130. https://doi.org/10.1007/978-3-319-14054-4_8S111130Abadi, M., Blanchet, B., Fournet, C.: Just fast keying in the pi calculus. ACM Trans. Inf. Syst. Secur. 10(3) (2007)Blanchet, B.: An Efficient Cryptographic Protocol Verifier Based on Prolog Rules. In: 14th IEEE Computer Security Foundations Workshop (CSFW 2014), Cape Breton, Nova Scotia, Canada, June 2001, pp. 82–96. IEEE Computer Society (2014)Bond, M.: Attacks on cryptoprocessor transaction sets. In: Koç, Ç.K., Naccache, D., Paar, C. (eds.) CHES 2001. LNCS, vol. 2162, pp. 220–234. Springer, Heidelberg (2001)Butler, F., Cervesato, I., Jaggard, A.D., Scedrov, A.: A formal analysis of some properties of kerberos 5 using msr. In: CSFW, pp. 175–1790. IEEE Computer Society (2002)Cachin, C., Chandran, N.: A secure cryptographic token interface. In: Proceedings of the 22nd IEEE Computer Security Foundations Symposium, CSF 2009, Port Jefferson, New York, USA, July 8-10, pp. 141–153 (2009)Chevalier, Y., Küsters, R., Rusinowitch, M., Turuani, M.: An NP decision procedure for protocol insecurity with XOR. In: 18th Annual IEEE Symposium on Logic in Computer Science, LICS 2003 (2003)Comon-Lundh, H., Shmatikov, V.: Intruder deductions, constraint solving and insecurity decision in presence of exclusive-or. In: 18th Annual IEEE Symposium on Logic in Computer Science (LICS 2003), pp. 271–280 (2003)Comon-Lundh, H., Cortier, V.: New decidability results for fragments of first-order logic and application to cryptographic protocols. In: Nieuwenhuis, R. (ed.) RTA 2003. LNCS, vol. 2706, pp. 148–164. Springer, Heidelberg (2003)Cortier, V., Keighren, G., Steel, G.: Automatic analysis of the aecurity of XOR-based key management schemes. In: Grumberg, O., Huth, M. (eds.) TACAS 2007. LNCS, vol. 4424, pp. 538–552. Springer, Heidelberg (2007)Cortier, V., Steel, G.: A generic security API for symmetric key management on cryptographic devices. In: Backes, M., Ning, P. (eds.) ESORICS 2009. LNCS, vol. 5789, pp. 605–620. Springer, Heidelberg (2009)Erbatur, S., et al.: Effective Symbolic Protocol Analysis via Equational Irreducibility Conditions. In: Foresti, S., Yung, M., Martinelli, F. (eds.) ESORICS 2012. LNCS, vol. 7459, pp. 73–90. Springer, Heidelberg (2012)Escobar, S., Meadows, C., Meseguer, J.: Maude-NPA: Cryptographic Protocol Analysis Modulo Equational Properties. In: Aldini, A., Barthe, G., Gorrieri, R. (eds.) FOSAD 2007/2008/2009. LNCS, vol. 5705, pp. 1–50. Springer, Heidelberg (2007)Escobar, S., Meadows, C., Meseguer, J., Santiago, S.: Sequential Protocol Composition in Maude-NPA. In: Gritzalis, D., Preneel, B., Theoharidou, M. (eds.) ESORICS 2010. LNCS, vol. 6345, pp. 303–318. Springer, Heidelberg (2010)Thayer Fabrega, F.J., Herzog, J., Guttman, J.: Strand Spaces: What Makes a Security Protocol Correct? Journal of Computer Security 7, 191–230 (1999)González-Burgueño, A.: Protocol Analysis Modulo Exclusive-Or Theories: A Case study in Maude-NPA. Master’s thesis, Universitat Politècnica de València (March 2014), https://angonbur.webs.upv.es/Previous_work/Master_Thesis.pdfIBM. Comment on Mike’s Bond paper A Chosen Key Difference Attack on Control Vectors (2001), http://www.cl.cam.ac.uk/~mkb23/research/CVDif-Response.pdfIBM. CCA basic services reference and guide: CCA basic services reference and guide for the IBM 4758 PCI and IBM 4764 (2001), http://www-03.ibm.com/security/cryptocards/pdfs/bs327.pdf.2008Keighren, G.: Model Checking IBM’s Common Cryptographic Architecture API. 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    An Optimizing Protocol Transformation for Constructor Finite Variant Theories in Maude-NPA

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    [EN] Maude-NPA is an analysis tool for cryptographic security protocols that takes into account the algebraic properties of the cryptosystem. Maude-NPA can reason about a wide range of cryptographic properties. However, some algebraic properties, and protocols using them, have been beyond Maude-NPA capabilities, either because the cryptographic properties cannot be expressed using its equational unification features or because the state space is unmanageable. In this paper, we provide a protocol transformation that can safely get rid of cryptographic properties under some conditions. The time and space difference between verifying the protocol with all the crypto properties and verifying the protocol with a minimal set of the crypto properties is remarkable. We also provide, for the first time, an encoding of the theory of bilinear pairing into Maude-NPA that goes beyond the encoding of bilinear pairing available in the Tamarin toolPartially supported by the EU (FEDER) and the Spanish MCIU under grant RTI2018-094403-B-C32, by the Spanish Generalitat Valenciana under grant PROMETEO/2019/098, and by the US Air Force Office of Scientific Research under award number FA9550-17-1-0286. Julia Sapiña has been supported by the Generalitat Valenciana APOSTD/2019/127 grantAparicio-Sánchez, D.; Escobar Román, S.; Gutiérrez Gil, R.; Sapiña-Sanchis, J. (2020). An Optimizing Protocol Transformation for Constructor Finite Variant Theories in Maude-NPA. Springer Nature. 230-250. https://doi.org/10.1007/978-3-030-59013-0_12S230250Maude-NPA manual v3.1. http://maude.cs.illinois.edu/w/index.php/Maude_Tools:_Maude-NPAThe Tamarin-Prover Manual, 4 June 2019. https://tamarin-prover.github.io/manual/tex/tamarin-manual.pdfAl-Riyami, S.S., Paterson, K.G.: Tripartite authenticated key agreement protocols from pairings. In: Paterson, K.G. (ed.) Cryptography and Coding 2003. LNCS, vol. 2898, pp. 332–359. Springer, Heidelberg (2003). https://doi.org/10.1007/978-3-540-40974-8_27Baader, F., Snyder, W.: Unification theory. In: Robinson, J.A., Voronkov, A. (eds.) Handbook of Automated Reasoning, vol. 1, pp. 447–533. Elsevier Science (2001)Baelde, D., Delaune, S., Gazeau, I., Kremer, S.: Symbolic verification of privacy-type properties for security protocols with XOR. In: 30th IEEE Computer Security Foundations Symposium, CSF 2017, pp. 234–248. IEEE Computer Society (2017)Blanchet, B.: Modeling and verifying security protocols with the applied pi calculus and ProVerif. Found. Trends Privacy Secur. 1(1–2), 1–135 (2016)Clavel, M., et al.: Maude manual (version 3.0). Technical report, SRI International, Computer Science Laboratory (2020). http://maude.cs.uiuc.eduComon-Lundh, H., Delaune, S.: The finite variant property: how to get rid of some algebraic properties. In: Giesl, J. (ed.) RTA 2005. LNCS, vol. 3467, pp. 294–307. Springer, Heidelberg (2005). https://doi.org/10.1007/978-3-540-32033-3_22Cremers, C.J.F.: The scyther tool: verification, falsification, and analysis of security protocols. In: Gupta, A., Malik, S. (eds.) CAV 2008. LNCS, vol. 5123, pp. 414–418. Springer, Heidelberg (2008). https://doi.org/10.1007/978-3-540-70545-1_38Dreier, J., Duménil, C., Kremer, S., Sasse, R.: Beyond subterm-convergent equational theories in automated verification of stateful protocols. In: Maffei, M., Ryan, M. (eds.) POST 2017. LNCS, vol. 10204, pp. 117–140. Springer, Heidelberg (2017). https://doi.org/10.1007/978-3-662-54455-6_6Escobar, S., Hendrix, J., Meadows, C., Meseguer, J.: Diffie-Hellman cryptographic reasoning in the Maude-NRL protocol analyzer. In: Proceedings of 2nd International Workshop on Security and Rewriting Techniques (SecReT 2007) (2007)Escobar, S., Meadows, C., Meseguer, J.: A rewriting-based inference system for the NRL protocol analyzer and its meta-logical properties. Theor. Comput. Sci. 367(1–2), 162–202 (2006)Escobar, S., Meadows, C., Meseguer, J.: Maude-NPA: cryptographic protocol analysis modulo equational properties. In: Aldini, A., Barthe, G., Gorrieri, R. (eds.) FOSAD 2007-2009. LNCS, vol. 5705, pp. 1–50. Springer, Heidelberg (2009). https://doi.org/10.1007/978-3-642-03829-7_1Escobar, S., et al.: Protocol analysis in Maude-NPA using unification modulo homomorphic encryption. In: Proceedings of PPDP 2011, pp. 65–76. ACM (2011)Escobar, S., Meadows, C.A., Meseguer, J., Santiago, S.: State space reduction in the Maude-NRL protocol analyzer. Inf. Comput. 238, 157–186 (2014)Escobar, S., Sasse, R., Meseguer, J.: Folding variant narrowing and optimal variant termination. J. Log. Algebr. Program. 81(7–8), 898–928 (2012)Fabrega, F.J.T., Herzog, J.C., Guttman, J.D.: Strand spaces: why is a security protocol correct? In: Proceedings of IEEE Symposium on Security and Privacy, pp. 160–171 (1998)Guttman, J.D.: Security goals and protocol transformations. In: Mödersheim, S., Palamidessi, C. (eds.) TOSCA 2011. LNCS, vol. 6993, pp. 130–147. Springer, Heidelberg (2012). https://doi.org/10.1007/978-3-642-27375-9_8Joux, A.: A one round protocol for tripartite Diffie-Hellman. In: Bosma, W. (ed.) ANTS 2000. LNCS, vol. 1838, pp. 385–393. Springer, Heidelberg (2000). https://doi.org/10.1007/10722028_23Kim, Y., Perrig, A., Tsudik, G.: Communication-efficient group key agreement. In: Dupuy, M., Paradinas, P. (eds.) SEC 2001. IIFIP, vol. 65, pp. 229–244. Springer, Boston, MA (2002). https://doi.org/10.1007/0-306-46998-7_16Küsters, R., Truderung, T.: Using ProVerif to analyze protocols with Diffie-Hellman exponentiation. In: IEEE Computer Security Foundations, pp. 157–171 (2009)Küsters, R., Truderung, T.: Reducing protocol analysis with XOR to the XOR-free case in the horn theory based approach. J. Autom. Reason. 46(3–4), 325–352 (2011)Meadows, C.: The NRL protocol analyzer: an overview. J. Logic Program. 26(2), 113–131 (1996)Meier, S., Cremers, C., Basin, D.: Strong invariants for the efficient construction of machine-checked protocol security proofs. In: 2010 23rd IEEE Computer Security Foundations Symposium, pp. 231–245 (2010)Meseguer, J.: Conditional rewriting logic as a united model of concurrency. Theoret. Comput. Sci. 96(1), 73–155 (1992)Meseguer, J.: Variant-based satisfiability in initial algebras. Sci. Comput. Program. 154, 3–41 (2018)Meseguer, J.: Generalized rewrite theories, coherence completion, and symbolic methods. J. Log. Algebr. Meth. Program. 110, 100483 (2020)Mödersheim, S., Viganò, L.: The open-source fixed-point model checker for symbolic analysis of security protocols. In: Aldini, A., Barthe, G., Gorrieri, R. (eds.) FOSAD 2007-2009. LNCS, vol. 5705, pp. 166–194. Springer, Heidelberg (2009). https://doi.org/10.1007/978-3-642-03829-7_6Sasse, R., Escobar, S., Meadows, C., Meseguer, J.: Protocol analysis modulo combination of theories: a case study in Maude-NPA. In: Cuellar, J., Lopez, J., Barthe, G., Pretschner, A. (eds.) STM 2010. LNCS, vol. 6710, pp. 163–178. Springer, Heidelberg (2011). https://doi.org/10.1007/978-3-642-22444-7_11Schmidt, B., Sasse, R., Cremers, C., Basin, D.A.: Automated verification of group key agreement protocols. In: 2014 IEEE Symposium on Security and Privacy, SP 2014, pp. 179–194. IEEE Computer Society (2014)Skeirik, S., Meseguer, J.: Metalevel algorithms for variant satisfiability. J. Log. Algebraic Methods Program. 96, 81–110 (2018)TeReSe: Term Rewriting Systems. Cambridge University Press, Cambridge (2003)Yang, F., Escobar, S., Meadows, C.A., Meseguer, J., Narendran, P.: Theories of homomorphic encryption, unification, and the finite variant property. In: Proceedings of PPDP 2014, pp. 123–133. ACM (2014

    Neuroinflammation and structural injury of the fetal ovine brain following intra-amniotic Candida albicans exposure.

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    BackgroundIntra-amniotic Candida albicans (C. Albicans) infection is associated with preterm birth and high morbidity and mortality rates. Survivors are prone to adverse neurodevelopmental outcomes. The mechanisms leading to these adverse neonatal brain outcomes remain largely unknown. To better understand the mechanisms underlying C. albicans-induced fetal brain injury, we studied immunological responses and structural changes of the fetal brain in a well-established translational ovine model of intra-amniotic C. albicans infection. In addition, we tested whether these potential adverse outcomes of the fetal brain were improved in utero by antifungal treatment with fluconazole.MethodsPregnant ewes received an intra-amniotic injection of 10(7) colony-forming units C. albicans or saline (controls) at 3 or 5 days before preterm delivery at 0.8 of gestation (term ~ 150 days). Fetal intra-amniotic/intra-peritoneal injections of fluconazole or saline (controls) were administered 2 days after C. albicans exposure. Post mortem analyses for fungal burden, peripheral immune activation, neuroinflammation, and white matter/neuronal injury were performed to determine the effects of intra-amniotic C. albicans and fluconazole treatment.ResultsIntra-amniotic exposure to C. albicans caused a severe systemic inflammatory response, illustrated by a robust increase of plasma interleukin-6 concentrations. Cerebrospinal fluid cultures were positive for C. albicans in the majority of the 3-day C. albicans-exposed animals whereas no positive cultures were present in the 5-day C. albicans-exposed and fluconazole-treated animals. Although C. albicans was not detected in the brain parenchyma, a neuroinflammatory response in the hippocampus and white matter was seen which was characterized by increased microglial and astrocyte activation. These neuroinflammatory changes were accompanied by structural white matter injury. Intra-amniotic fluconazole reduced fetal mortality but did not attenuate neuroinflammation and white matter injury.ConclusionsIntra-amniotic C. albicans exposure provoked acute systemic and neuroinflammatory responses with concomitant white matter injury. Fluconazole treatment prevented systemic inflammation without attenuating cerebral inflammation and injury
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