Characterization of Alaskan Hot-Mix Asphalt containing Reclaimed Asphalt Pavement Material

In order to properly characterize Alaskan HMA materials containing RAP, this study evaluated properties of 3 asphalt binders typically used in Alaska, PG 52-28, PG 52-40, and PG 58-34, and 11 HMA mixtures containing up to 35% RAP that were either produced in the lab or collected from existing paving projects in Alaska. Various binder and mixture engineering properties were determined, including true high binder grades, complex modulus (|G*|), and phase angle (δ) at high performance temperatures, MSCR recovery rate and compliance, BBR stiffness and m-value, DTT failure stress and strain for binders, and dynamic modulus, flow number, IDT creep stiffness and strength for mixtures. Binder cracking temperatures were determined through Thermal Stress Analysis Routine (TSAR) software along with BBR and DTT data. Mixture cracking temperatures were determined with IDT creep stiffness and strength data. It was found that rutting may not be a concern with Alaskan RAP mix, while low-temperature cracking concerns may still exist in RAP mix in Alaska. A savings of $13.3/ton was estimated for a 25% RAP mix, with consideration of Alaskan situations. Many recommendations for future RAP practice and research are recommended based on testing results and cost analysis.Alaska Department of Transportation Statewide Research Offic

Performance of TenCate Paving Interlayers in Asphalt Concrete Pavements

As a continued effort of a previously completed project entitled “Performance of TenCate Mirafi PGM-G4 Interlayer-Reinforced Asphalt Pavements in Alaska,” this project evaluated two newly modified paving interlayers (TruPave and Mirapave) through overlay, dynamic modulus tests and low-temperature performance tests. A field survey was conducted to further evaluate the performance of three paving interlayers (G4, G50/50, and G100/100) applied to field sections constructed in May 2013 at Milepost 148–156 Richardson Highway in Alaska. Overlay test results indicate that asphalt concrete (AC) with paving interlayers (TruPave and Mirapave) shows lower reduction in peak load, suggesting better cracking resistance. The dynamic modulus measurement of AC with paving interlayers reveals more rational results from the IDT mode test than the AMPT method due to similar stress conditions in the paving interlayer. With paving interlayers, the temperature sensitivity and cracking potential of AC material were reduced according to the results from the IDT creep test. Field survey results confirm that all sections reinforced with paving interlayers (G4, G50/50, and G100/100) had better cracking resistance than the control section.TenCate Geosynthetics North Americ

Scene Graph Generation with External Knowledge and Image Reconstruction

Scene graph generation has received growing attention with the advancements in image understanding tasks such as object detection, attributes and relationship prediction,~\etc. However, existing datasets are biased in terms of object and relationship labels, or often come with noisy and missing annotations, which makes the development of a reliable scene graph prediction model very challenging. In this paper, we propose a novel scene graph generation algorithm with external knowledge and image reconstruction loss to overcome these dataset issues. In particular, we extract commonsense knowledge from the external knowledge base to refine object and phrase features for improving generalizability in scene graph generation. To address the bias of noisy object annotations, we introduce an auxiliary image reconstruction path to regularize the scene graph generation network. Extensive experiments show that our framework can generate better scene graphs, achieving the state-of-the-art performance on two benchmark datasets: Visual Relationship Detection and Visual Genome datasets.Comment: 10 pages, 5 figures, Accepted in CVPR 201

Supersymmetric QCD corrections to single top quark production at hadron colliders

We present the calculations of the supersymmetric QCD corrections to the total cross sections for single top production at the Fermilab Tevatron and the CERN Large Hadron Collider in the minimal supersymmetric standard model. Our results show that for the s-channel and t-channel, the supersymmetric QCD corrections are at most about 1%, but for the associated production process, the supersymmetric QCD corrections increase the total cross sections significantly, which can reach about 6% for most values of the parameters, and the supersymmetric QCD corrections should be taken into consideration in the future high precision experimental analysis for top physics.Comment: 33 pages, 19 figures, version to appear in Phys.Rev.

Threshold Resummation Effects in the Associated Production of Chargino and Neutralino at Hadron Colliders

We investigate the QCD effects in the associated production of the chargino and the neutralino, $\tilde\chi^\pm_{1}$ and $\tilde\chi^0_{2}$, in the Minimal Supersymmetric Standard Model (MSSM) at both the Fermilab Tevatron and the CERN Large Hadron Collider (LHC). We include the next-to-leading order (NLO) QCD corrections (including supersymmetric QCD) and the threshold resummation effects. Our results show that, compared to the NLO predictions, the threshold resummation effects can increase the total cross sections by 3.6% and 3.9% for the associated production of $\tilde\chi^+_{1}\tilde\chi^0_{2}$ and $\tilde\chi^-_{1}\tilde\chi^0_{2}$ at the LHC, respectively, and by 4.7% for those of $\tilde\chi^\pm_{1}\tilde\chi^0_{2}$ at the Tevatron. In the invariant mass distributions the resummation effects are significant for large invariant mass. The threshold resummation reduces the dependence of the total cross sections at the LHC (Tevatron) on the renormalization/factorization scales to 5% (4%) from up to 7% (11%) at NLO.Comment: revised version with midifications, several references adde

Assessment of density functional approximations for the hemibonded structure of water dimer radical cation

Due to the severe self-interaction errors associated with some density functional approximations, conventional density functionals often fail to dissociate the hemibonded structure of water dimer radical cation (H2O)2+ into the correct fragments: H2O and H2O+. Consequently, the binding energy of the hemibonded structure (H2O)2+ is not well-defined. For a comprehensive comparison of different functionals for this system, we propose three criteria: (i) The binding energies, (ii) the relative energies between the conformers of the water dimer radical cation, and (iii) the dissociation curves predicted by different functionals. The long-range corrected (LC) double-hybrid functional, omegaB97X-2(LP) [J.-D. Chai and M. Head-Gordon, J. Chem. Phys., 2009, 131, 174105.], is shown to perform reasonably well based on these three criteria. Reasons that LC hybrid functionals generally work better than conventional density functionals for hemibonded systems are also explained in this work.Comment: 10 pages, 5 figures, 4 table