863 research outputs found

    FLARE: Fingerprinting Deep Reinforcement Learning Agents using Universal Adversarial Masks

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    We propose FLARE, the first fingerprinting mechanism to verify whether a suspected Deep Reinforcement Learning (DRL) policy is an illegitimate copy of another (victim) policy. We first show that it is possible to find non-transferable, universal adversarial masks, i.e., perturbations, to generate adversarial examples that can successfully transfer from a victim policy to its modified versions but not to independently trained policies. FLARE employs these masks as fingerprints to verify the true ownership of stolen DRL policies by measuring an action agreement value over states perturbed via such masks. Our empirical evaluations show that FLARE is effective (100% action agreement on stolen copies) and does not falsely accuse independent policies (no false positives). FLARE is also robust to model modification attacks and cannot be easily evaded by more informed adversaries without negatively impacting agent performance. We also show that not all universal adversarial masks are suitable candidates for fingerprints due to the inherent characteristics of DRL policies. The spatio-temporal dynamics of DRL problems and sequential decision-making process make characterizing the decision boundary of DRL policies more difficult, as well as searching for universal masks that capture the geometry of it.Comment: Will appear in the proceedings of ACSAC 2023; 13 pages, 5 figures, 7 table

    Ab-initio computation of neutron-rich oxygen isotopes

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    We compute the binding energy of neutron-rich oxygen isotopes and employ the coupled-cluster method and chiral nucleon-nucleon interactions at next-to-next-to-next-to-leading order with two different cutoffs. We obtain rather well-converged results in model spaces consisting of up to 21 oscillator shells. For interactions with a momentum cutoff of 500 MeV, we find that 28O is stable with respect to 24O, while calculations with a momentum cutoff of 600 MeV result in a slightly unbound 28O. The theoretical error estimates due to the omission of the three-nucleon forces and the truncation of excitations beyond three-particle-three-hole clusters indicate that the stability of 28O cannot be ruled out from ab-initio calculations, and that three-nucleon forces and continuum effects play the dominant role in deciding this question.Comment: 5 pages + eps, 3 figure

    In Things We Trust? Towards trustability in the Internet of Things

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    This essay discusses the main privacy, security and trustability issues with the Internet of Things

    Customer participation and service outcomes: Mediating role of task-related affective well-being

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    This paper contributes to transformative service research by drawing on self-determination, elicitation of emotions framework, and feelings-as-information theories to explore how customer participation, task-related affective well-being, customer knowledge, task complexity, and service outcomes relate with each other. Design/methodology/approach-A synthesis of relevant literature on customer participation and customer well-being reveals a conceptual model with eleven testable propositions. Findings-The conceptual model shows that task-related affective well-being mediates the link between customer participation and service outcomes. Moreover, customer knowledge and task complexity moderate these links. Research limitations/implications-An empirically testable conceptual model models the roles of task-related affective well-being, customer knowledge and task complexity in the process by which customer participation influences service outcomes. Practical implications-Service managers can use the model to design services based on the effects of different types of customer participation on task-related affective well-being. Originality/value-This paper is one of the first to study the mediating role of task-related affective well-being in the relationship between customer participation and service outcomes. It does so by revealing the differential impact various types of participation have on service outcomes and the moderating role of customer knowledge and task complexity

    In vitro regeneration of Brahmi (Bacopa monnieri (Linn.) Pennell) - an important medicinal herb through nodal segment culture

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    An efficient and cost effective in vitro plant regeneration protocol through nodalsegment culture was achieved in the medicinally important herb Bacopa monnieri (L.)Pennell, the Memory Plus plant through axillary shoot proliferation in Murashige and Skooge medium augmented with varying concentrations of 6-benzylaminopurine (BAP)1 - 5 mg/l. BAP at 2 mg/l was the most effective in multiple shoot induction and mean number of leaves, which gave an average of 17 shoots and 31.11 leaves, compared toother concentrations of the hormone tried in 35 days of culture. Regarding mean shoot length and number of nodes, basal MS giving 2.66 cm long shoots with 7.44 nodes is thebest. MS basal medium, even though not promoting shoot multiplication, gave highershoot length with elongated internodes. Healthy rooting of the in vitro developed shootswas achieved in half and full strength MS basal solid medium without the addition ofany hormones. The healthy and vigorous in vitro regenerated micro shoots wereseparated out and were hardened on transfer to plastic cups with sterile soil and sandand were successfully acclimatized ex vitro in pots with potting mixture under greenhouse conditions for 3 weeks. The survival rate was 100% and the plants establishedwell in green house resembled the mother plants in habitat without any morphological variations. The very simple and cost effective protocol developed can be used to produceelite stable clones for en masse propagation for the large-scale cultivation of this very important medicinal herb

    In vitro propagation of Lesser Galangal (Alpinia calcarata Rosc.) - a commercially important medicinal plant through rhizome bud culture

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    An efficient protocol has been established for clonal propagation of Alpinia calcarata, a commercially important medicinal plant on Murashige and Skooge medium usingrhizome bud explants. Of the different concentrations of 6-benzylaminopurine (BAP) andBAP in combination with different levels of kinetin, the best response of axillary shootproliferation was achieved in a combination of 1.5 mg/l of kinetin in combination with 0.5mg/l of BAP producing 13.6 shoots per explant in 6-8 weeks of culture followed by 2 mg/lkinetin and 0.5 mg/l BAP with an average of 6.2 shoot buds from each of the explants.Rooting of the shoots also occurred in the same medium in 3 weeks of subculture. Shootstransferred to half strength MS medium with 0.5 mg/l IBA was optimum for healthyrooting. The healthy in vitro rooted plants were hardened on plastic cups in sterile sand andwere transferred to pots containing potting mixture under green house conditions for 3-4weeks for acclimatization. The survival rate was 87-90% and the plants established well inthe field and developed rhizomes after 4-6 weeks of growth under shade house. Thisprotocol proves its utility for rapid propagation of A. calcarata, which can be exploited forpharmaceutical and commercial purpose

    Peptide affinity reagents for AAV capsid recognition and purification

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    We report the discovery of AAV capsid-binding peptides identified through phage panning. The heptapeptide motif GYVSRHP selectively recognized AAV serotype 8 capsids and blocked transduction in vitro. Recombinant AAV8 vectors were purified directly from crude cell lysate and supernatant through sequential application of peptide affinity and anion exchange chromatography. Peptide affinity reagents may serve as useful alternatives to monoclonal antibodies in AAV capsid recognition, and offer readily scalable solutions for purification of clinical grade AAV vectors
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