667 research outputs found

    Applying Abstract Argumentation Theory to Cooperative Game Theory

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    We apply ideas from abstract argumentation theory to study cooperative game theory. Building on Dung's results in his seminal paper, we further the correspondence between Dung's four argumentation semantics and solution concepts in cooperative game theory by showing that complete extensions (the grounded extension) correspond to Roth's subsolutions (respectively, the supercore). We then investigate the relationship between well-founded argumentation frameworks and convex games, where in each case the semantics (respectively, solution concepts) coincide; we prove that three-player convex games do not in general have well-founded argumentation frameworks.Comment: 15 pages, 1 tabl

    The Intermediate Mass Black Hole Candidate in the Center of NGC 404: New Evidence from Radio Continuum Observations

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    We present the results of deep, high-resolution, 5 GHz Expanded Very Large Array (EVLA) observations of the nearby, dwarf lenticular galaxy and intermediate mass black hole candidate (M ~4.5 x 10^5 M_sun), NGC 404. For the first time, radio emission at frequencies above 1.4 GHz has been detected in this galaxy. We found a modestly resolved source in the NGC 404 nucleus with a total radio luminosity of 7.6 +/- 0.7 x 10^17 W/Hz at 5 GHz and a spectral index from 5 to 7.45 GHz of alpha = -0.88 +/- 0.30. NGC 404 is only the third central intermediate mass black hole candidate detected in the radio regime with subarcsecond resolution. The position of the radio source is consistent with the optical center of the galaxy and the location of a known, hard X-ray point source (Lx ~1.2 x 10^37 erg/s). The faint radio and X-ray emission could conceivably be produced by an X-ray binary, star formation, a supernova remnant or a low-luminosity AGN powered by an intermediate mass black hole. In light of our new EVLA observations, we find that the most likely scenario is an accreting intermediate mass black hole, with other explanations incompatible with the observed X-ray and/or radio luminosities or statistically unlikely.Comment: Accepted for publication to Ap

    Social Engineering Cyber Threats

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    The article explores the pervasive threat of social engineering in cybersecurity, emphasizing its success in infiltrating information systems by manipulating individuals rather than employing traditional hacking methods. The author underscores the vulnerability arising from human trust, as individuals, especially those lacking technology education, tend to be targets. While cryptography offers partial security, social engineering complicates overall system security. Mitigation strategies include educating employees on threats, risks, and security policies, coupled with enforcing penalties for noncompliance. Additionally, employing two-factor authentication and physical token-based access adds layers of protection. The article delves into semantic attacks, classifying various exploitation methods and emphasizing the critical role of user awareness. It addresses prevalent scams such as phishing, vishing, impersonation, and smishing, noting their impact on individuals and organizations. The study extends its focus globally, highlighting a unique advance fee fraud targeting vulnerable populations. Social engineering remains a significant challenge despite technological advancements, necessitating a multifaceted approach combining technical defenses, education, and public awareness

    Is incident rheumatoid arthritis interstitial lung disease associated with methotrexate treatment? Results from a multivariate analysis in the ERAS and ERAN inception cohorts

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    © Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.Objectives To assess predictive factors for rheumatoid arthritis interstitial lung disease (RA-ILD) in two early RA inception cohorts with a focus on methotrexate (MTX) exposure. Design Multicenter prospective early RA inception cohort studies; the early RA study (ERAS) and the early RA network (ERAN) Setting Secondary care, ERAS 9 centers, ERAN 23 centers in England, Wales and the Republic of Ireland Participants Patients with new diagnosis of RA, n=2701.Standardised data including demographics, drug therapies and clinical outcomes including the presence of RA-ILD were collected at baseline, within 3- 6 months, at 12 months and annually thereafter. Primary and secondary outcome measures Primary outcome was the association of MTX exposure on RA-ILD diagnosis. Secondary outcomes were the association of demographic, comorbid and RA specific factors on RA-ILD diagnosis and the association of MTX exposure on time to RA-ILD diagnosis. Results Of 92 eligible ILD cases, 39 occurred in 1578 (2.5%) MTX exposed and 53 in 1114 (4.8%) non-MTX exposed cases. The primary analysis of RA-ILD cases only developing after any csDMARD treatment (n=67) showed MTX exposure not to be associated with incident RA-ILD (O.R. 0.85 CI 0.49, 1.49 p=0.578) and a non-significant trend for delayed ILD diagnosis (O.R. 0.54 CI 0.28, 1.06 p=0.072). In an extended analysis including RA-ILD cases present at RA diagnosis (n=92), MTX exposure was associated with a significantly reduced risk of incident RA-ILD (O.R. 0.48, CI 0.3, 0.79 p=0.004) and longer time to ILD diagnosis (O.R. 0.41, CI 0.23, 0.75 p=0.004). Other independent baseline associations with incident RA-ILD were higher age of RA onset, ever smoking, male gender, rheumatoid nodules and longer time from first RA symptom to first out-patient visit. Conclusions MTX treatment was not associated with an increased risk of RA-ILD diagnosis. On the contrary evidence suggested that MTX may delay the onset of ILD.Peer reviewe

    Paper Session II-B - Future Sustainable H2 Infrastructure

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    The researchers hypothesized that it is possible to efficiently use an alternative ener61Y source, rather than the combustion of hydrocarbons. The researchers found that the most efficient, abundant, environmentally friendly, reusable energy sources is Hydrogen. One of the most efficient methods of utilizing hydrogen was through the use of Proton Exchange Membrane Fuel Cells. After thorough research into Proton Exchange Membrane Fuel Cells, or PEMFC\u27s, the researchers constructed a working prototype of the fuel cell using easily obtainable materials. Many previous designs were studied and discussed. Newer designs were created to compensate for the use of easily obtainable materials. After a series of testing and redesigning, a high efficiency rating was achieved. The research supported the hypothesis made by the researchers and exceeded many of their expectations, despite the simple construction methods

    Libbie & Grove Urban Design Plan

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    This plan was created for the City of Richmond Department of Planning and Development Review to serve as a recommendation for urban design improvements and suggested changes to zoning ordinances for the Libbie and Grove commercial area located in the Westhampton neighborhood. To begin, an in-depth demographic analysis was conducted for the Westhampton neighborhood. Special attention was paid to socioeconomic factors and trends in census tracts directly surrounding the Libbie and Grove commercial corridor. Based on these analyses and new development occurring in the Libbie and Grove commercial corridor, we were able to allocate six sites or “study areas” as candidates for redevelopment. All of these sites represent valuable areas within the Libbie and Grove commercial corridor. The sites were selected and designed with different intentions, but aim to create a complete streetscape for the commercial area. Based on this analysis and study, it is our recommendation that a new zoning code be implemented for the Libbie and Grove commercial area in order to codify form based design requirements in order to preserve and enhance a village feel at Grove and Libbie and promote compatible future development

    EcoModule: a fungible, eco-friendly learning experience

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    Designed to fit the needs and wants of classes in elementary schools, our product aims to provide an interactive and engaging system through which they can learn about different ecosystems in a fun and highly educational way.Ope
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