547 research outputs found

    NLO QCD + NLO EW corrections to WZZWZZ productions with leptonic decays at the LHC

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    Precision tests of the Standard Model (SM) require not only accurate experiments, but also precise and reliable theoretical predictions. Triple vector boson production provides a unique opportunity to investigate the quartic gauge couplings and check the validity of the gauge principle in the SM. Since the tree-level predictions alone are inadequate to meet this demand, the next-to-leading order (NLO) calculation becomes compulsory. In this paper, we calculate the NLO QCD + NLO electroweak (EW) corrections to the WΒ±ZZW^{\pm}ZZ productions with subsequent leptonic decays at the 14Β TeV14~{\rm TeV} LHC by adopting an improved narrow width approximation which takes into account the off-shell contributions and spin correlations from the WΒ±W^{\pm}- and ZZ-boson leptonic decays. The NLO QCD+EW corrected integrated cross sections for the WΒ±ZZW^{\pm}ZZ productions and some kinematic distributions of final products are provided. The results show that both the NLO QCD and NLO EW corrections are significant. In the jet-veto event selection scheme with pT,jetcut=50Β GeVp_{T,jet}^{cut} = 50~ {\rm GeV}, the NLO QCD+EW relative corrections to the integrated cross section are 20.5%20.5\% and 31.1%31.1\%, while the genuine NLO EW relative corrections are βˆ’5.42%-5.42\% and βˆ’4.58%-4.58\%, for the W+ZZW^+ZZ and Wβˆ’ZZW^-ZZ productions, respectively. We also investigate the theoretical dependence of the integrated cross section on the factorization/renormalization scale, and find that the scale uncertainty is underestimated at the LO due to the fact that the strong coupling Ξ±s\alpha_s is not involved in the LO matrix elements.Comment: 19 pages, 8 figure

    Unified Data-Free Compression: Pruning and Quantization without Fine-Tuning

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    Structured pruning and quantization are promising approaches for reducing the inference time and memory footprint of neural networks. However, most existing methods require the original training dataset to fine-tune the model. This not only brings heavy resource consumption but also is not possible for applications with sensitive or proprietary data due to privacy and security concerns. Therefore, a few data-free methods are proposed to address this problem, but they perform data-free pruning and quantization separately, which does not explore the complementarity of pruning and quantization. In this paper, we propose a novel framework named Unified Data-Free Compression(UDFC), which performs pruning and quantization simultaneously without any data and fine-tuning process. Specifically, UDFC starts with the assumption that the partial information of a damaged(e.g., pruned or quantized) channel can be preserved by a linear combination of other channels, and then derives the reconstruction form from the assumption to restore the information loss due to compression. Finally, we formulate the reconstruction error between the original network and its compressed network, and theoretically deduce the closed-form solution. We evaluate the UDFC on the large-scale image classification task and obtain significant improvements over various network architectures and compression methods. For example, we achieve a 20.54% accuracy improvement on ImageNet dataset compared to SOTA method with 30% pruning ratio and 6-bit quantization on ResNet-34.Comment: ICCV202

    Learning Global-aware Kernel for Image Harmonization

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    Image harmonization aims to solve the visual inconsistency problem in composited images by adaptively adjusting the foreground pixels with the background as references. Existing methods employ local color transformation or region matching between foreground and background, which neglects powerful proximity prior and independently distinguishes fore-/back-ground as a whole part for harmonization. As a result, they still show a limited performance across varied foreground objects and scenes. To address this issue, we propose a novel Global-aware Kernel Network (GKNet) to harmonize local regions with comprehensive consideration of long-distance background references. Specifically, GKNet includes two parts, \ie, harmony kernel prediction and harmony kernel modulation branches. The former includes a Long-distance Reference Extractor (LRE) to obtain long-distance context and Kernel Prediction Blocks (KPB) to predict multi-level harmony kernels by fusing global information with local features. To achieve this goal, a novel Selective Correlation Fusion (SCF) module is proposed to better select relevant long-distance background references for local harmonization. The latter employs the predicted kernels to harmonize foreground regions with both local and global awareness. Abundant experiments demonstrate the superiority of our method for image harmonization over state-of-the-art methods, \eg, achieving 39.53dB PSNR that surpasses the best counterpart by +0.78dB ↑\uparrow; decreasing fMSE/MSE by 11.5\%↓\downarrow/6.7\%↓\downarrow compared with the SoTA method. Code will be available at \href{https://github.com/XintianShen/GKNet}{here}.Comment: 10 pages, 10 figure

    cyclo-TetraΒ­kis{ΞΌ-2,2β€²-dimethyl-1,1β€²-[2,2-bisΒ­(bromoΒ­methΒ­yl)propane-1,3-diΒ­yl]di(1H-benzimidazole)-ΞΊ2 N 3:N 3β€²}tetraΒ­kisΒ­[bromidocopper(I)]

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    The title compound, [Cu4Br4(C21H22Br2N4)4], features a macrocyclic Cu4 L 4 ring system in which each CuI atom is coordinated by one bromide ion and two N atoms from two 2,2β€²-dimethyl-1,1β€²-[2,2-bisΒ­(bromoΒ­methΒ­yl)propane-1,3-diΒ­yl]di(1H-benzimidazole) (L) ligands in a distorted trigonal–planar geometry. The L ligands adopt either a cis or trans configuration. The asymmetric unit contains one half-molΒ­ecule with the center of the macrocycle located on a crystallographic center of inversion. Each bromide ion binds to a CuI atom in a terminal mode and is oriented outside the ring. The macrocycles are interΒ­connected into a two-dimensional network by π–π interΒ­actions between benzimidΒ­azole groups from different rings [centroid–centroid distance = 3.803β€…(5)β€…Γ…
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