6,639 research outputs found

    On acquisition of programming knowledge

    Get PDF
    For the evolving discipline of programming, acquisition of programming knowledge is a difficult issue. Common knowledge results from the acceptance of proven techniques based on results of formal inquiries into the nature of the programming process. This is a rather slow process. In addition, the vast body of common knowledge needs to be explicated to a low enough level of details for it to be represented in the machine processable form. It is felt that this is an impediment to the progress of automatic programming. The importance of formal approaches cannot be overstated since their contributions lead to quantum leaps in the state of the art

    Improving the efficiency of spam filtering through cache architecture

    Get PDF
    Blacklists (BLs), also called Domain Name Systembased Blackhole List (DNSBLs) are the databases of known internet addresses used by the spammers to send out the spam mails. Mail servers use these lists to filter out the e-mails coming from different spam sources. In contrary, Whitelists (WLs) are the explicit list of senders from whom e-mail can be accepted or delivered. Mail Transport Agent (MTA) is usually configured to reject, challenge or flag the messages which have been sent from the sources listed on one or more DNSBLs and to allow the messages from the sources listed on the WLs. In this paper, we are demonstrating how the bandwidth (the overall requests and responses that need to go over the network) performance is improved by using local caches for BLs and WLs. The actual sender\u27s IP addresses are extracted from the e-mail log. These are then compared with the list in the local caches to find out if they should be accepted or not, before they are checked against the global DNSBLs by running \u27DNSBL queries\u27 (if required). Around three quarters of the e-mail sources have been observed to be filtered locally through caches with this method. Provision of local control over the lists and lower search (filtering) time are the other related benefits. © 2008 IEEE

    Thermal instability in a gravity-like scalar theory

    Full text link
    We study the question of stability of the ground state of a scalar theory which is a generalization of the phi^3 theory and has some similarity to gravity with a cosmological constant. We show that the ground state of the theory at zero temperature becomes unstable above a certain critical temperature, which is evaluated in closed form at high temperature.Comment: Four pages, two figures. Revised version published in the Physical Review

    Parity-violating electromagnetic interactions in QED_3 at finite temperature

    Get PDF
    We study the parity-breaking terms generated by the box diagram in 2+1 dimensional thermal QED. These lead, in the long wave limit, to a gauge invariant extensive action which behaves as 1/T at high temperature. In contrast, the effective action in the static limit involves leading non-extensive terms proportional to 1/T^3 at high temperature, which violate large gauge invariance. We derive a non-linear large gauge Ward identity, which relates the leading static terms of different order in perturbation theory and whose solution coincides with the all order effective action proposed earlier.Comment: 25 pages, 3 figure

    Dispersion relations for the self-energy in non-commutative field theories

    Full text link
    We study the IR/UV connection in non-commutative ϕ3\phi^{3} theory as well as in non-commutative QED from the point of view of the dispersion relation for the self-energy. We show that, although the imaginary part of the self-energy is well behaved as the parameter of non-commutativity vanishes, the real part becomes divergent as a consequence of the high energy behavior of the dispersion integral. Some other interesting features that arise from this analysis are also briefly discussed.Comment: 10 page

    Balancing Justice Needs and Private Property in Constitutional Takings Provisions: A Comparative Assessment of India, Australia, and the United States

    Get PDF
    This Article explores the relationship between justice needs and private property in the constitutional takings provisions of the Indian, Australian, and American constitutions. Building upon established scholarship, it develops a theoretical framework within which to consider the way in which a state balances the requirement to provide minimal levels of justice for its citizens through the re-distribution of goods and resources with the need to protect the private property of individuals. We summarize this framework in what we refer to as the “Justice Needs-Protection of Private Property Continuum.” Using the framework developed, the Article provides an outline of the takings provisions found in the Indian, Australian, and American constitutions. Part I examines Article 300A of the Constitution of India, which contains the scope of the power of compulsory acquisition exercised by the Indian state. Part II assesses Section 51(xxxi) of the Australian Constitution which, unlike its American and Indian counterparts, operates as both a grant of power to the federal government, as well as a limitation imposed upon that power, which may, it seems, operate so as to provide some minimal protection for individual private property interests. Part III considers the Takings Clause of the Fifth Amendment to the United States Constitution which, as interpreted by the Supreme Court, provides perhaps the most robust means among the three jurisdictions considered for protecting the individual private property interests as against state takings. The Conclusion offers comparative reflections on the nature of the takings provision found in each jurisdiction.Krithika Ashok, Paul T. Babie, & John V. Ort
    • 

    corecore