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Little Rock, AR, United States

Philander Smith College is a private historically black college, four-year undergraduate liberal arts institution, located in Little Rock, Arkansas. Philander Smith College is affiliated with the United Methodist Church and a founding member of the United Negro College Fund . Philander Smith College is accredited by the North Central Association of Colleges and Schools. The Mission of Philander Smith College is, "To graduate academically accomplished students who are grounded as advocates for social justice, determined to change the world for the better." Wikipedia.

Park I.Y.,Philander Smith College
Journal of High Energy Physics | Year: 2014

We reduce the BTZ spacetime to two kinds of hypersurfaces of foliation: one having a fixed radial coordinate and the other a fixed angular coordinate. The radial reduction leads to a Liouville type theory, and confirms, from the first principle, the expectation laid out in the literature. In the other endeavor, the angular reduction of the 3D gravity is carried out in two different ways; the first again yields a Liouville type theory (different from that of the radial reduction) and the second yields a 2D interacting quantum field theory with quartic potential. We discuss potential implications of our result for the Equivalence Principle and Purity of Hawking radiation. © 2014 Author(s). Source

Hatefi E.,International Center for Theoretical Physics | Park I.Y.,Philander Smith College
Nuclear Physics B | Year: 2012

Knowledge of all-α ' higher derivative corrections to leading order BPS and non-BPS brane actions would serve in future endeavor of determining the complete form of the non-abelian BPS and tachyonic effective actions. In this paper, we note that there is a universality in the all-α ' order corrections to BPS and non-BPS branes. We compute amplitudes between one Ramond-Ramond C-field vertex operator and several SYM gauge/scalar vertex operators. Specifically, we evaluate in closed form string correlators of two-point amplitudes A Cφ, A CA, a three-point amplitude A Cφφ, and a four-point amplitude A Cφφφ. We carry out pole and contact term analysis. In particular we reproduce some of the contact terms and the infinite massless poles of A Cφφφ by SYM vertices obtained through the universality. © 2012 Elsevier B.V. Source

Hatefi E.,International Center for Theoretical Physics | Park I.Y.,Philander Smith College
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012

In our continued efforts of matching full string computations with the corresponding effective field theory computations, we evaluate string theory correlators in closed forms. In particular, we consider a correlator between three super Yang-Mills vertex operators and one Ramond-Ramond C-field vertex operator: 〈V CV φV AV A〉. We show that the infinite number of massless poles of this amplitude can be reproduced by the Born-Infeld action, the Wess-Zumino terms, and their higher derivative corrections. More specifically, we find, up to an on-shell ambiguity, two scalar field and two gauge field couplings to all orders in α ′ such that the infinite number of massless poles of the field theory amplitude exactly match the infinite number of massless poles of the S-matrix elements of 〈V CV φV AV A〉. We comment on the close intertwinedness of an open string and a closed string that must be behind the matching. © 2012 American Physical Society. Source

Hatefi E.,International Center for Theoretical Physics | Nurmagambetov A.J.,Ai Akhiezer Institute For Theoretical Physics Of Nsc Kipt | Park I.Y.,Philander Smith College
Nuclear Physics B | Year: 2013

We observe that the N 3 entropy behavior of near-extremal M5 branes can be reproduced from SYM side with the role of Myers' terms. We start by generalizing the Klebanov-Tseytlin (KT) supergravity solution that displays the N 3 entropy behavior. The new feature of the general solution is visibility of the "internal" degrees of the M5 branes, i.e., the M0 branes and the M2 branes. With the rationale provided by the supergravity analysis, we consider a D0 brane quantum mechanical setup with Myers' terms. Using localization technique, we show that the leading N 3 behavior of the free energy comes from the "classical contribution" with the rest subleading. © 2012 Elsevier B.V. Source

Zhang C.,Philander Smith College | Kodell R.L.,University of Arkansas for Medical Sciences
Artificial Intelligence in Medicine | Year: 2013

Objective: Although classification algorithms are promising tools to support clinical diagnosis and treatment of disease, the usual implicit assumption underlying these algorithms, that all patients are homogeneous with respect to characteristics of interest, is unsatisfactory The objective here is to exploit the population heterogeneity reflected by characteristics that may not be apparent and thus not controlled, in order to differentiate levels of classification accuracy between subpopulations and further the goal of tailoring therapies on an individual basis Methods and materials: A new subpopulation-based confidence approach is developed in the context of a selective voting algorithm defined by an ensemble of convex-hull classifiers Populations of training samples are divided into three subpopulations that are internally homogeneous, with different levels of predictivity Two different distance measures are used to cluster training samples into subpopulations and assign test samples to these subpopulations Results: Validation of the new approach's levels of confidence of classification is carried out using six publicly available datasets Our approach demonstrates a positive correspondence between the predictivity designations derived from training samples and the classification accuracy of test samples The average difference between highest- and lowest-confidence accuracies for the six datasets is 17.8%, with a minimum of 11.3% and a maximum of 24.1% Conclusion: The classification accuracy increases as the designated confidence increases © 2013 Elsevier B.V. Source

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