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Query modeling for click data based image recognition using graph based propagation and sparse coding

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Query modeling for click data based image recognition using ...

9th International Conference on Internet Multimedia Computing and Service, ICIMCS 2017

作者： Wu, Weichen Tan, Min Zheng, Guangjian Yu, Jun Key Laboratory of Complex Systems Modeling and Simulation School of Computer Science and Technology Hangzhou Dianzi University Hangzhou310018 China

ISBN: (纸本)9789811085291

We address the fine-grained image recognition problem using user click data, wherein each image is represented as a semantical query-click feature vector. Usually, the query set obtained from search engines is large-scale and redundant. We propose a novel query modeling approach to merge semantically similar queries and construct a compact click feature. We represent each query as a click feature, and design a graph based propagation approach to predict the zero-clicks, ensuring similar images have similar clicks. Afterwards, using this feature, we formulate the problem as a sparse coding based recognition task, wherein the dictionary is discriminatively trained. We evaluate our method for fine-grained image recognition on the public Clickture-Dog dataset. It is shown that, the propagated click feature performs much better than the original one. Also, sparse coding performs better than K-means in query merging. © Springer Nature Singapore Pte Ltd. 2018.

关键词： Image recognition

The ${ {\bar{\boldsymbol q}\boldsymbol q\bar{\boldsymbol s}\boldsymbol Q} \;\;{(\boldsymbol q {\bf =}\boldsymbol u,\,\boldsymbol d;\,\boldsymbol Q{\bf =}\boldsymbol c,\,\boldsymbol b)} }$ tetraquark system in a chiral quark model*

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Chinese Physics C 2024年第7期48卷 073106-073106页

作者： Gang Yang Jialun Ping Jorge Segovia Department of Physics Zhejiang Normal University Jinhua 321004 China Department of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing 210023 China Departamento de Sistemas Físicos Químicos y Naturales Universidad Pablo de Olavide E-41013 Sevilla Spain

The S-wave $\bar{q}q\bar{s}Q \;\; (q=u,\,d;\,Q=c,\,b)$ tetraquarks, with spin-parities $J^P=0^+$, $1^+$, and $2^+$, in both isoscalar and isovector sectors, are systematically studied using a chiral quark model. The

The S-wave $\bar{q}q\bar{s}Q \;\; (q=u,\,d;\,Q=c,\,b)$ $\bar{q}q\bar{s}Q \;\; (q=u,\,d;\,Q=c,\,b)$ tetraquarks, with spin-parities $ J^P=0^+ $ $J^P=0^+$, $ 1^+ $ $1^+$, and $ 2^+ $ $2^+$, in both isoscalar and isovector sectors, are systematically studied using a chiral quark model. The

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Study of Bs → K(∗)+− decays in the PQCD factorization approach with the lattice QCD input

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arXiv 2020年

作者： Jin, Su-Ping Hu, Xue-Qing Xiao, Zhen-Jun Department of Physics and Institute of Theoretical Physics Nanjing Normal University Nanjing Jiangsu210023 China Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing210023 China

In this paper, we studied systematically the semileptonic decays Bs → K(∗)+− with l− = (e−,µ−,τ−) by using the perturbative QCD (PQCD) and the "PQCD+Lattice" factorization approach, respectively. We first evaluated all relevant form factors Fi(q2) in the low q2 region using the PQCD approach, and we also take the available Lattice QCD results at the end point qmax2 as additional input to improve the extrapolation of the form factors to the high q2 region. We calculated the branching ratios and other twelve kinds of physical observables: AFB(l), PL, FLK∗ and the angular observables Pi and Pj′. From our studies, we find the following points: (a) for Bs → Kl+l− decays, the PQCD and "PQCD+Lattice" predictions for branching ratios (BRs) B(Bs → Kl+l−), the ratios of the BRs RKeµ,µτ and the longitudinal polarization asymmetry of the leptons PL agree well within errors;(b) the "PQCD+Lattice" prediction B(Bs → K∗µ+µ−) = (2.58+0−0..6960)×10−8 does agree well with the LHCb measured value (2.9 ± 1.1) × 10−8;(c) for the ratios RKeµ∗ and RKµτ∗, the PQCD and "PQCD+Latatice" predictions agree very well and have a small error less than 10% due to the cancellation of the theoretical uncertainties in the ratios of the branching ratios;(d) for the angular observables P1,2,3 and P4′,5,6,8 , our theoretical predictions for each lepton l− are consistent within errors;(e) the theoretical predictions of the angular observables P3 and P6′,8 are less than 10−2 in absolute value, but the magnitude of P1,2 and P4′,5 are larger than 0.2;and (f) the PQCD and "PQCD+Lattice" predictions of the binned values of all considered observables in the two q2-bins [0.1 − 0.98]GeV2 and [1.1 − 6]GeV2 generally agree with each other and also be consistent with the LCSR results within errors. We believe that above predictions could be measured by future LHCb and Belle-II experiments. Copyright © 2020, The Authors. All rights reserved.

关键词： Quantum theory

Study of Bs→ φ+-decays in the PQCD factorization approach with lattice QCD input

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arXiv 2020年

作者： Jin, Su-Ping Xiao, Zhen-Jun Department of Physics and Institute of Theoretical Physics Nanjing Normal University Jiangsu Nanjing210023 China Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing210023 China

In this paper, we studied systematically the semileptonic decays Bs→ φl+l-with l-= (e-, μ-, τ-) by using the perturbative QCD (PQCD) and the "PQCD+Lattice" factorization approach, respectively. We first evaluated all relevant form factors Fi(q2) in the low q2region using the PQCD approach, and we also took the available lattice QCD results at the high-q2region as additional input to improve the extrapolation of Fi(q2) from the low-q2region to the endpoint qmax2. We then calculated the branching ratios and many other physical observables: AFBl, FLφ, S3,4,7, A5,6,8,9and the clean angular observables P1,2,3and P'4,5,6,8. From our studies, we find the following points: (a) the PQCD and "PQCD+Lattice" predictions of B(Bs→ φμ+μ-) are about 7×10-7, which agree well with the LHCb measured values and the QCD sum rule prediction within still large errors;(b) we defined and calculated the ratios of the branching ratios Rφeμand Rφμτ;(c) the PQCD and "PQCD+Lattice" predictions of the longitudinal polarization FL, the CP averaged angular coefficients S3,4,7and the CP asymmetry angular coefficients A5,6,8,9, agree with the LHCb measurements in all considered bins within the still large experimental errors;and (d) for those currently still unknown observables Rφeμ,Rφμτ,AFBl, P1,2,3and P'4,5,6,8, we suggest LHCb and Belle-II Collaboration to measure them in their experiments. © 2020, CC BY.

关键词： Quantum theory

Impact of Ligand Fields on Kubas Interaction of Open Copper Sites in Mofs with Hydrogen Molecules: An Electronic Structural Insight

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SSRN

SSRN 2024年

作者： Nguyen-Thuy, Trang Tran-Van, Hoan Nguyen-Hoang, Linh Nguyen-Minh, Hoang Phan, Bach Thang Nguyen-The, Toan Kawazoe, Yoshiyuki Faculty of physics University of Science Vietnam National University – Hanoi Hanoi Viet Nam School of engineering physics Hanoi University of Technology Hanoi Viet Nam Center for Innovative Materials and Architectures Vietnam National University Ho Chi Minh City Ho Chi Minh City Viet Nam Vietnam National University HoChiMinh City Viet Nam Key Laboratory for Multiscale Simulation of Complex Systems University of Science Vietnam National University – Hanoi Hanoi Viet Nam New Industry Creation Hatchery Center Tohoku University Sendai980-8579 Japan Department of Physics and Nanotechnology SRM Institute of Science and Technology Tamil Nadu Kattankulathur603203 India School of Physics Institute of Science Suranaree University of Technology 111 University Avenue Nakhon Ratchasima30000 Thailand

Using DFT calculations, we investigate hydrogen sorption on open copper sites in various ligand coordinations of metal-organic frameworks (MOFs), including the triangle coordination T(CuL3) in MFU-4l, the linear coordination L(CuL2) in NU2100 and the paddlewheel coordination P(CuL4)2 in HKUST-1. By examining the ligand field splitting of d states and spd hybridizations in copper, we reveal the electronic mechanisms influencing hydrogen sorption performance. Despite Cu+ oxidization state which is expected to facilitate strong Kubas interaction with hydrogen molecules, the vacant s-p-dz2 hybrid orbitals of the open copper site in the L(CuL2) coordination are unsuitable for overlapping with the H2 s bonding orbital, preventing hydrogen adsorption. In contrast, the T(CuL3) and P(CuL4)2 coordinations enable hydrogen adsorption by inducing suitable hydrid orbitals. The vacant Cu s-p-dz2 hybrid orbitals in these cases can overlap with the H2 s bonding orbital to facilitate electron forward donation, forming bonding states between the Cu s-p-dz2 and H2 s bonding orbitals. The occupied Cu s-p-dxz/yz and s-p-dx2-y2 hybrid orbitals in the case of T(CuL3) promote the electron back donation to the H2 s* antibonding orbital, leading to the formation of bonding states. Conversely, in P(CuL4)2 coordination, the absence of such hybridization results in the lack of electron back donation. The complete Kubas interaction with both forward and back electron donations is responsible for a higher adsorption energy of 37.6 kJ/mol in the case of T(CuL3) than the value of 10.6 kJ/mol in the P(CuL4)2 coordination. © 2024, The Authors. All rights reserved.

关键词： Electronic structure

sQq¯q¯ (q=u, d;Q=c, b) tetraquarks in the chiral quark model

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Physical Review D 2021年第7期103卷 074011-074011页

The low-lying sQq¯q¯ (q=u, d, Q=c, b) tetraquark states with JP=0+, 1+, and 2+, and in the isoscalar and isovector sectors, are systematically investigated in the framework of the real- and complex-scaling range of a chiral quark model, whose parameters are fixed in advance describing hadron, hadron-hadron, and multiquark phenomenology, and thus, all results presented here are pure predictions. Each tetraquark configuration compatible with the quantum numbers studied is taken into account; this includes meson-meson, diquark-antidiquark, and K-type arrangements of quarks with all possible color wave functions in the four-body sector. Among the different numerical techniques to solve the Schrödinger-like four-body bound-state equation, we use a variational method in which the trial wave function is expanded in complex-range Gaussian basis functions because of its simplicity and flexibility. Several compact bound states and narrow resonances are found in both charm-strange csq¯q¯ and bottom-strange bsq¯q¯ tetraquark sectors, most of them as a product of the strong coupling between the different channels. In regard to the so-called X0,1(2900) structures recently discovered with good statistical significance by the LHCb Collaboration, whose properties point out to be csu¯d¯ tetraquarks, we find that they are unstable in our formalism with several candidates in the single-channel computations. We distinguish four cases with I(JP)=0(0+) quantum numbers: three K-type configurations with masses at 2.89, 2.96, and 2.97 GeV, and one hidden-color coupled-channel calculation delivering a mass 2.86 GeV. With quantum numbers I(JP)=0(1+), only one candidate can be found in the hidden-color coupled-channel calculation with mass 2.94 GeV.

关键词： Quantum chromodynamics Quark model

On Exploring Undetermined Relationships for Visual Relationship Detection

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On Exploring Undetermined Relationships for Visual Relations...

IEEE/CVF Conference on Computer Vision and Pattern Recognition

作者： Yibing Zhan Jun Yu Ting Yu Dacheng Tao Key Laboratory of Complex Systems Modeling and Simulation School of Computer Science and Technology Hangzhou Dianzi University UBTECH Sydney AI Centre School of Computer Science FEIT University of Sydney

ISBN: (纸本)9781728132945

In visual relationship detection, human-notated relationships can be regarded as determinate relationships. However, there are still large amount of unlabeled data, such as object pairs with less significant relationships or even with no relationships. We refer to these unlabeled but potentially useful data as undetermined relationships. Although a vast body of literature exists, few methods exploit these undetermined relationships for visual relationship detection. In this paper, we explore the beneficial effect of undetermined relationships on visual relationship detection. We propose a novel multi-modal feature based undetermined relationship learning network (MF-URLN) and achieve great improvements in relationship detection. In detail, our MF-URLN automatically generates undetermined relationships by comparing object pairs with human-notated data according to a designed criterion. Then, the MF-URLN extracts and fuses features of object pairs from three complementary modals: visual, spatial, and linguistic modals. Further, the MF-URLN proposes two correlated subnetworks: one subnetwork decides the determinate confidence, and the other predicts the relationships. We evaluate the MF-URLN on two datasets: the Visual Relationship Detection (VRD) and the Visual Genome (VG) datasets. The experimental results compared with state-of-the-art methods verify the significant improvements made by the undetermined relationships, e.g., the top-50 relation detection recall improves from 19.5% to 23.9% on the VRD dataset.

关键词： Visualization Fuses Dataset

DeepFlame: A deep learning empowered open-source platform for reacting flow simulations

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arXiv 2022年

作者： Mao, Runze Lin, Minqi Zhang, Yan Zhang, Tianhan John Xu, Zhi-Qin Chen, Zhi X. State Key Laboratory of Turbulence and Complex Systems Aeronautics and Astronautics College of Engineering Peking University Beijing100871 China Ai for Science Institute Beijing100080 China Caep Software Center for High Performance Numerical Simulation Beijing100088 China Institute of Applied Physics and Computational Mathematics Beijing100088 China Department of Mechanics and Aerospace Engineering SUSTech Shenzhen518055 China Institute of Natural Sciences School of Mathematical Sciences Shanghai Jiao Tong University Shanghai200240 China MOE-LSC Qing Yuan Research Institute Shanghai Jiao Tong University Shanghai200240 China

Recent developments in deep learning have brought many inspirations for the scientific computing community and it is perceived as a promising method in accelerating the computationally demanding reacting flow simulations. In this work, we introduce DeepFlame, an open-source C++ platform with the capabilities of utilising machine learning algorithms and pre-trained models to solve for reactive flows. We combine the individual strengths of the computational fluid dynamics library OpenFOAM, machine learning framework Torch, and chemical kinetics program Cantera. The complexity of cross-library function and data interfacing (the core of DeepFlame) is minimised to achieve a simple and clear workflow for code maintenance, extension and upgrading. As a demonstration, we apply our recent work on deep learning for predicting chemical kinetics (Zhang et al. Combust. Flame vol. 245 pp. 112319, 2022) to highlight the potential of machine learning in accelerating reacting flow simulation. A thorough code validation is conducted via a broad range of canonical cases to assess its accuracy and efficiency. The results demonstrate that the convection-diffusion-reaction algorithms implemented in DeepFlame are robust and accurate for both steady-state and transient processes. In addition, a number of methods aiming to further improve the computational efficiency, e.g. dynamic load balancing and adaptive mesh refinement, are explored. Their performances are also evaluated and reported. With the deep learning method implemented in this work, a speed-up of two orders of magnitude is achieved in a simple hydrogen ignition case when performed on a medium-end graphics processing unit (GPU). Further gain in computational efficiency is expected for hydrocarbon and other complex fuels. A similar level of acceleration is obtained on an AI-specific chip - deep computing unit (DCU), highlighting the potential of DeepFlame in leveraging the next-generation computing architecture and hardware. © 202

关键词： Graphics processing unit

Arbitrary high-order linear structure-preserving schemes for the regularized long-wave equation

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arXiv 2021年

作者： Jiang, Chaolong Qian, Xu Song, Songhe Cui, Jin Department of Mathematics College of Liberal Arts and Science National University of Defense Technology Changsha410073 China School of Statistics and Mathematics Yunnan University of Finance and Economics Kunming650221 China Department of Basic Sciences Nanjing Vocational College of Information Technology Nanjing210023 China Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems School of Mathematical Sciences Nanjing Normal University Nanjing210023 China

In this paper, a class of arbitrarily high-order linear momentum-preserving and energy-preserving schemes are proposed, respectively, for solving the regularized long-wave equation. For the momentum-preserving scheme, the key idea is based on the extrapolation/prediction-correction technique and the symplectic Runge-Kutta method in time, together with the standard Fourier pseudo-spectral method in space. We show that the scheme is linear, high-order, unconditionally stable and preserves the discrete momentum of the system. For the energy-preserving scheme, it is mainly based on the energy quadratization approach and the analogous linearized strategy used in the construction of the linear momentum-preserving scheme. The proposed scheme is linear, high-order and can preserve a discrete quadratic energy exactly. Numerical results are addressed to demonstrate the accuracy and efficiency of the proposed scheme. Copyright © 2021, The Authors. All rights reserved.

关键词： Runge Kutta methods