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SCOAP3
Subject 물리학 Source SCOAP3 URL https://repo.scoap3.org/record/18185view Article Title Thermodynamic geometry and phase transitions of AdS braneworld black holesAuthors Chaturvedi, Pankaj; Sengupta, GautamAbstract The thermodynamics and phase transitions of charged RN–AdS and rotating Kerr–AdS black holes in a generalized Randall–Sundrum braneworld are investigated in the framework of thermodynamic geometry. A detailed analysis of the thermodynamics, stability and phase structures in the canonical and the grand canonical ensembles for these AdS braneworld black holes are described. The thermodynamic curvatures for both these AdS braneworld black holes are computed and studied as a function of the thermodynamic variables. Through this analysis we illustrate an interesting dependence of the phase structures on the braneworld parameter for these black holes.Is Part Of PHYSICS_LETTERS_B 2016 Identifier ISSN: 0370-2693 DOI 10.1016/j.physletb.2016.12.003Publisher ElsevierCategory Resources PDF: http://repo.scoap3.org/record/18185/files/main.pdf
License CC-BY-3.0 -
arXiv
Subject Source arXiv URL https://arxiv.org/abs/1701.00128view Article Title Steering Orbital Optimization out of Local Minima and Saddle Points Toward Lower EnergyAuthors Alain C. Vaucher; Markus ReiherAbstract The general procedure underlying Hartree-Fock and Kohn-Sham density functional theory calculations consists in optimizing orbitals for a self-consistent solution of the Roothaan-Hall equations in an iterative process. It is often ignored that multiple self-consistent solutions can exist, several of which may correspond to minima of the energy functional. In addition to the difficulty sometimes encountered to converge the calculation to a self-consistent solution, one must ensure that the correct self-consistent solution was found, typically the one with the lowest electronic energy. Convergence to an unwanted solution is in general not trivial to detect and will deliver incorrect energy and molecular properties, and accordingly a misleading description of chemical reactivity. Wrong conclusions based on incorrect self-consistent field convergence are particularly cumbersome in automated calculations met in high-throughput virtual screening, structure optimizations, ab initio molecular dynamics, and in real-time explorations of chemical reactivity, where the vast amount of data can hardly be manually inspected. Here, we introduce a fast and automated approach to detect and cure incorrect orbital convergence, which is especially suited for electronic structure calculations on sequences of molecular structures. Our approach consists of a randomized perturbation of the converged electron density (matrix) intended to push orbital convergence to solutions that correspond to another stationary point (of potentially lower electronic energy) in the variational parameter space of an electronic wave function approximation.Is Part Of J. Chem. Theory Comput., 2017, 13 (3), pp 1219-1228 2016-12-31 Identifier ISSN: DOI 10.1021/acs.jctc.7b00011Category physics.chem-ph cond-mat.mtrl-sci physics.comp-phLicense -
arXiv
Subject 수학 Source arXiv URL https://arxiv.org/abs/1701.00736view Article Title Simulated Tornado OptimizationAuthors S. Hossein Hosseini; Tohid Nouri; Afshin Ebrahimi; S. Ali HosseiniAbstract We propose a swarm-based optimization algorithm inspired by air currents of a tornado. Two main air currents - spiral and updraft - are mimicked. Spiral motion is designed for exploration of new search areas and updraft movements is deployed for exploitation of a promising candidate solution. Assignment of just one search direction to each particle at each iteration, leads to low computational complexity of the proposed algorithm respect to the conventional algorithms. Regardless of the step size parameters, the only parameter of the proposed algorithm, called tornado diameter, can be efficiently adjusted by randomization. Numerical results over six different benchmark cost functions indicate comparable and, in some cases, better performance of the proposed algorithm respect to some other metaheuristics.Is Part Of 2016-12-31 Identifier ISSN: Category math.OC cs.AI cs.NELicense -
arXiv
Subject 수학 Source arXiv URL https://arxiv.org/abs/1701.00120view Article Title Approximation and equidistribution results for pseudo-effective line bundlesAuthors Dan Coman; George Marinescu; Viêt-Anh NguyênAbstract We study the distribution of the common zero sets of $m$-tuples of holomorphic sections of powers of $m$ singular Hermitian pseudo-effective line bundles on a compact K\"ahler manifold. As an application, we obtain sufficient conditions which ensure that the wedge product of the curvature currents of these line bundles can be approximated by analytic cycles.Is Part Of J. Math. Pures Appl. (9) 115 (2018), 218-236 2016-12-31 Identifier ISSN: DOI 10.1016/j.matpur.2017.09.010Category math.CV math-ph math.DG math.MPLicense -
arXiv
Subject Source arXiv URL https://arxiv.org/abs/1701.00140view Article Title A Finite Presentation of CNOT-Dihedral OperatorsAuthors Matthew Amy; Jianxin Chen; Neil J. RossAbstract We give a finite presentation by generators and relations of the unitary operators expressible over the {CNOT, T, X} gate set, also known as CNOT-dihedral operators. To this end, we introduce a notion of normal form for CNOT-dihedral circuits and prove that every CNOT-dihedral operator admits a unique normal form. Moreover, we show that in the presence of certain structural rules only finitely many circuit identities are required to reduce an arbitrary CNOT-dihedral circuit to its normal form. By appropriately restricting our relations, we obtain a finite presentation of unitary operators expressible over the {CNOT, T} gate set as a corollary.Is Part Of EPTCS 266, 2018, pp. 84-97 2016-12-31 Identifier ISSN: DOI 10.4204/EPTCS.266.5Category quant-ph cs.ET cs.LOLicense -
Springer Nature
Subject Source Springer Nature URL http://dx.doi.org/10.1007/s11017-016-9393-5view Article Title Indeterminacy and the principle of needAuthors Herlitz, AndersAbstract AbstractThe principle of need—the idea that resources should be allocated according to need—is often invoked in priority setting in the health care sector. In this article, I argue that a reasonable principle of need must be indeterminate, and examine three different ways that this can be dealt with: appendicizing the principle with further principles, imposing determinacy, or empowering decision makers. I argue that need must be conceptualized as a composite property composed of at least two factors: health shortfall and capacity to benefit. When one examines how the different factors relate to each other, one discovers that this is sometimes indeterminate. I illustrate this indeterminacy in this article by applying the small improvement argument. If the relation between the factors are always determinate, the comparative relation changes by a small adjustment. Yet, if two needs are dissimilar but of seemingly equal magnitude, the comparative relation does not change by a small adjustment of one of the factors. I then outline arguments in favor of each of the three strategies for dealing with indeterminacy, but also point out that all strategies have significant shortcomings. More research is needed concerning how to deal with this indeterminacy, and the most promising path seems to be to scrutinize the position of the principle of need among a plurality of relevant principles for priority setting in the health care sector.Is Part Of Theoretical Medicine and Bioethics 2016-12-31 , Vol.38 (1) , 1 Identifier EISSN: null ; PISSN: DOI 10.1007/s11017-016-9393-5Publisher SpringerLicense ©2016 The Author(s) -
arXiv
Subject 수학 Source arXiv URL https://arxiv.org/abs/1701.00181view Article Title The effect of boundary conditions on mixing of 2D Potts models at discontinuous phase transitionsAuthors Reza Gheissari; Eyal LubetzkyAbstract We study Swendsen--Wang dynamics for the critical $q$-state Potts model on the square lattice. For $q=2,3,4$, where the phase transition is continuous, the mixing time $t_{\textrm{mix}}$ is expected to obey a universal power-law independent of the boundary conditions. On the other hand, for large $q$, where the phase transition is discontinuous, the authors recently showed that $t_{\textrm{mix}}$ is highly sensitive to boundary conditions: $t_{\textrm{mix}} \geq \exp(cn)$ on an $n\times n$ box with periodic boundary, yet under free or monochromatic boundary conditions, $t_{\textrm{mix}} \leq\exp(n^{o(1)})$. In this work we classify this effect under boundary conditions that interpolate between these two (torus vs. free/monochromatic). Specifically, if one of the $q$ colors is red, mixed boundary conditions such as red-free-red-free on the 4 sides of the box induce $t_{\textrm{mix}} \geq \exp(cn)$, yet Dobrushin boundary conditions such as red-red-free-free, as well as red-periodic-red-periodic, induce sub-exponential mixing.Is Part Of 2016-12-31 Identifier ISSN: Category math.PR math-ph math.MPLicense -
SCOAP3
Subject 물리학 Source SCOAP3 URL https://repo.scoap3.org/record/18224view Article Title Investigating the spectral anomaly with different reactor antineutrino experimentsAuthors Buck, C.; Collin, A.P.; Haser, J.; Lindner, M.Abstract The spectral shape of reactor antineutrinos measured in recent experiments shows anomalies in comparison to neutrino reference spectra. New precision measurements of the reactor neutrino spectra as well as more complete input in nuclear data bases are needed to resolve the observed discrepancies between models and experimental results. This article proposes the combination of experiments at reactors which are highly enriched in U235 with commercial reactors with typically lower enrichment to gain new insights into the origin of the anomalous neutrino spectrum. The presented method clarifies, if the spectral anomaly is either solely or not at all related to the predicted U235 spectrum. Considering the current improvements of the energy scale uncertainty of present-day experiments, a significance of three sigma and above can be reached. As an example, we discuss the option of a direct comparison of the measured shape in the currently running Double Chooz near detector and the upcoming Stereo experiment. A quantitative feasibility study emphasizes that a precise understanding of the energy scale systematics is a crucial prerequisite in recent and next generation experiments investigating the spectral anomaly.Is Part Of PHYSICS_LETTERS_B 2016 Identifier ISSN: 0370-2693 DOI 10.1016/j.physletb.2016.11.062Publisher ElsevierCategory Antineutrino; Neutrino; Reactor spectrum; Reactor anomaly; Nuclear reactorResources PDF: http://repo.scoap3.org/record/18224/files/main.pdf
License CC-BY-3.0 -
SCOAP3
Subject 물리학 Source SCOAP3 URL https://repo.scoap3.org/record/18242view Article Title Production of the doubly charmed baryons at the SELEX experiment – The double intrinsic charm approachAuthors Koshkarev, Sergey; Anikeev, VladimirAbstract The high production rate and 〈xF〉>0.33 of the doubly charmed baryons measured by the SELEX experiment is not amenable to perturbative QCD analysis. In this paper we calculate the production of the doubly heavy baryons with the double intrinsic charm Fock states whose existence is rigorously predicted by QCD. The production rate and the longitudinal momentum distribution are both reproduced. We also show that the production rates of the doubly charmed baryons and double J/ψ production observed by NA3 collaboration are comparable. Recent experimental results are reviewed. The production cross section of the doubly charmed baryons at a fixed-target experiment at the LHC is presented.Is Part Of PHYSICS_LETTERS_B 2016 Identifier ISSN: 0370-2693 DOI 10.1016/j.physletb.2016.12.010Publisher ElsevierCategory Resources PDF: http://repo.scoap3.org/record/18242/files/main.pdf
License CC-BY-3.0 -
arXiv
Subject Source arXiv URL https://arxiv.org/abs/1701.00169view Article Title Vertical stratification of forest canopy for segmentation of under-story trees within small-footprint airborne LiDAR point cloudsAuthors Hamid Hamraz; Marco A. Contreras; Jun ZhangAbstract Airborne LiDAR point cloud representing a forest contains 3D data, from which vertical stand structure even of understory layers can be derived. This paper presents a tree segmentation approach for multi-story stands that stratifies the point cloud to canopy layers and segments individual tree crowns within each layer using a digital surface model based tree segmentation method. The novelty of the approach is the stratification procedure that separates the point cloud to an overstory and multiple understory tree canopy layers by analyzing vertical distributions of LiDAR points within overlapping locales. The procedure does not make a priori assumptions about the shape and size of the tree crowns and can, independent of the tree segmentation method, be utilized to vertically stratify tree crowns of forest canopies. We applied the proposed approach to the University of Kentucky Robinson Forest - a natural deciduous forest with complex and highly variable terrain and vegetation structure. The segmentation results showed that using the stratification procedure strongly improved detecting understory trees (from 46% to 68%) at the cost of introducing a fair number of over-segmented understory trees (increased from 1% to 16%), while barely affecting the overall segmentation quality of overstory trees. Results of vertical stratification of the canopy showed that the point density of understory canopy layers were suboptimal for performing a reasonable tree segmentation, suggesting that acquiring denser LiDAR point clouds would allow more improvements in segmenting understory trees. As shown by inspecting correlations of the results with forest structure, the segmentation approach is applicable to a variety of forest types.Is Part Of ISPRS Journal of Photogrammetry and Remote Sensing 130C (2017) pp. 385-392 2016-12-31 Identifier ISSN: DOI 10.1016/j.isprsjprs.2017.07.001Category cs.CV cs.CE cs.CGLicense