7,189 research outputs found

    Reevaluating the Computer Fraud and Abuse Act: Amending the Statute to Explicitly Address the Cloud

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    Under the current interpretations of authorization, instances where an individual harmlessly accesses the cloud data of another user could be classified as hacking and a violation of this federal statute. As such, this Note demonstrates that all of the current interpretations of the CFAA are too broad because they could result in this nonsensical outcome. This Note accordingly proposes an amendment to the CFAA specifically addressing user access to data on the cloud. Such an amendment would eliminate the unusual result of innocuous cloud-computing users being deemed hackers under federal law

    Generalized Du Fort-Frankel methods for parabolic initial boundary value problems

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    The Du Fort-Frankel difference scheme is generalized to difference operators of arbitrary high order accuracy in space and to arbitrary order of the parabolic differential operator. Spectral methods can also be used to approximate the spatial part of the differential operator. The scheme is explicit, and it is unconditionally stable for the initial value problem. Stable boundary conditions are given for two different fourth order accurate space approximations

    On the Navier-Stokes equations with constant total temperature

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    For various applications in fluid dynamics, it is assumed that the total temperature is constant. Therefore, the energy equation can be replaced by an algebraic relation. The resulting set of equations in the inviscid case is analyzed. It is shown that the system is strictly hyperbolic and well posed for the initial value problems. Boundary conditions are described such that the linearized system is well posed. The Hopscotch method is investigated and numerical results are presented

    Composition changes in the lower thermosphere

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    Chemical heating above polar thermosphere and formation of helium bulge during winte

    Heavy Dynamical Fermions in Lattice QCD

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    It is expected that the only effect of heavy dynamical fermions in QCD is to renormalize the gauge coupling. We derive a simple expression for the shift in the gauge coupling induced by NfN_f flavors of heavy fermions. We compare this formula to the shift in the gauge coupling at which the confinement-deconfinement phase transition occurs (at fixed lattice size) from numerical simulations as a function of quark mass and NfN_f. We find remarkable agreement with our expression down to a fairly light quark mass. However, simulations with eight heavy flavors and two light flavors show that the eight flavors do more than just shift the gauge coupling. We observe confinement-deconfinement transitions at β=0\beta=0 induced by a large number of heavy quarks. We comment on the relevance of our results to contemporary simulations of QCD which include dynamical fermions.Comment: COLO-HEP-311, 26 pages and 6 postscript figures; file is a shar file and all macros are (hopefully) include

    An adaptive pseudo-spectral method for reaction diffusion problems

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    The spectral interpolation error was considered for both the Chebyshev pseudo-spectral and Galerkin approximations. A family of functionals I sub r (u), with the property that the maximum norm of the error is bounded by I sub r (u)/J sub r, where r is an integer and J is the degree of the polynomial approximation, was developed. These functionals are used in the adaptive procedure whereby the problem is dynamically transformed to minimize I sub r (u). The number of collocation points is then chosen to maintain a prescribed error bound. The method is illustrated by various examples from combustion problems in one and two dimensions

    Comparing the R algorithm and RHMC for staggered fermions

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    The R algorithm is widely used for simulating two flavours of dynamical staggered fermions. We give a simple proof that the algorithm converges to the desired probability distribution to within O(dt^2) errors, but show that the relevant expansion parameter is (dt/m)^2, m being the quark mass. The Rational Hybrid Monte Carlo (RHMC) algorithm provides an exact (i.e., has no step size errors) alternative for simulating the square root of the staggered Dirac operator. We propose using it to test the validity of the R algorithm for simulations carried out with dt m.Comment: 3 pages, proceedings from Lattice 2002 poster presentatio

    Strong Stability Preserving Two-Step Runge-Kutta Methods

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    We investigate the strong stability preserving (SSP) property of two-step Runge– Kutta (TSRK) methods. We prove that all SSP TSRK methods belong to a particularly simple\ud subclass of TSRK methods, in which stages from the previous step are not used. We derive simple order conditions for this subclass. Whereas explicit SSP Runge–Kutta methods have order at most four, we prove that explicit SSP TSRK methods have order at most eight. We present TSRK methods of up to eighth order that were found by numerical search. These methods have larger SSP coefficients than any known methods of the same order of accuracy, and may be implemented in a form with relatively modest storage requirements. The usefulness of the TSRK methods is demonstrated through numerical examples, including integration of very high order WENO discretizations

    An examination of social workers\u27 and other therapists\u27 use of transference and countertransference as therapeutic tools in couples counselling within the psychoanalytic paradigm

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    The purpose of this study is to increase knowledge about therapeutic practices on the part of practitioners; specifically, the study asked social workers and other types of therapists who see couples about their awareness of, acknowledgment of, attitude toward, understanding of, and use of the psychoanalytic model and of the concepts of transference and countertransference, and to demonstrate to what extent they accurately comprehend the meaning and potential use of these concepts in their clinical practice. A survey/questionnaire was mailed to a large sample of social workers and other therapists in Ontario, and provided 941 responses. An included vignette gave respondents the opportunity to put their theoretical knowledge into clinical application. Responses were assessed through scoring on key indices of awareness of, acknowledgment of, understanding of, attitude toward, and use of transference and countertransference. This study provided evidence of a deficiency in these indices and in the use of the psychoanalytic model on the part of practitioners who treat couples. Only 6.1% of these respondents selected the psychoanalytic paradigm as their first choice in treating couples. Few couples counsellors considered transference and/or countertransference as key issues in assessment. (Of these practitioners, only 7.5% gave at least one accurate example). Results from this study revealed a significant disparity between practitioners\u27 theoretical knowledge and their practical application. A linear model was employed to identify predictors of application/use of transference and countertransference. The most important predictor was respondents\u27 perception of the psychoanalytic model in terms of its usefulness in treating the couple presented in the vignette. The object relations model was used to help explicate the findings of this study. Implications of this study included the need for further training of practitioners in order to increase their theoretical knowledge and clinical skills concerning use of the psychoanalytic paradigm and of the concepts of transference and countertransference
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