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Study of Bs←φ+- Decays in the PQCD Factorization Approach with Lattice QCD Input

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Advances in High Energy Physics 2021年 2021卷

作者： Jin, Su-Ping Xiao, Zhen-Jun Department of Physics and Institute of Theoretical Physics Nanjing Normal University NanjingJiangsu210023 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 Fiq2 in the low-q2 region using the PQCD approach, and we also took the available lattice QCD results at the high-q2 region as additional input to improve the extrapolation of Fiq2 from the low-q2 region to the endpoint qmax2. We then calculated the branching ratios and many other physical observables AFBl, FLφ, S3,4,7, and A5,6,8,9 and the clean angular observables P1,2,3 and P4,5,6,8′. From our studies, we find the following points: (a) the PQCD and "PQCD+Lattice"predictions of BBs←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 Rφeμ and Rφμτ;(c) the PQCD and "PQCD+Lattice"predictions of the longitudinal polarization FL, the CP-averaged angular coefficients S3,4,7, and 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,P1,2,3, and P4,5,6,8′, we suggest LHCb and Belle-II Collaboration to measure them in their experiments. © 2021 Su-Ping Jin and Zhen-Jun Xiao.

关键词： Forecasting

Exploring the Physical World Adversarial Robustness of Vehicle Detection

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arXiv 2023年

作者： Jiang, Wei Zhang, Tianyuan Liu, Shuangcheng Ji, Weiyu Zhang, Zichao Xiao, Gang Information Science Academy China Eletronics Technology Group Corporation Beijing100846 China Beihang University Beijing China National Key Laboratory for Complex Systems Simulation Beijing China

Adversarial attacks can compromise the robustness of real-world detection models. However, evaluating these models under real-world conditions poses challenges due to resource-intensive experiments. Virtual simulations offer an alternative, but the absence of standardized benchmarks hampers progress. Addressing this, we propose an innovative instant-level data generation pipeline using the CARLA simulator. Through this pipeline, we establish the Discrete and Continuous Instant-level (DCI) dataset, enabling comprehensive experiments involving three detection models and three physical adversarial attacks. Our findings highlight diverse model performances under adversarial conditions. Yolo v6 demonstrates remarkable resilience, experiencing just a marginal 6.59% average drop in average precision (AP). In contrast, the ASA attack yields a substantial 14.51% average AP reduction, twice the effect of other algorithms. We also note that static scenes yield higher recognition AP values, and outcomes remain relatively consistent across varying weather conditions. Intriguingly, our study suggests that advancements in adversarial attack algorithms may be approaching its "limitation".In summary, our work underscores the significance of adversarial attacks in real-world contexts and introduces the DCI dataset as a versatile benchmark. Our findings provide valuable insights for enhancing the robustness of detection models and offer guidance for future research endeavors in the realm of adversarial attacks. Copyright © 2023, The Authors. All rights reserved.

关键词： Pipelines

Heat conduction in one-dimensional aperiodic quantum Ising chains

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Physical Review E 2011年第3期83卷 031128-031128页

作者： Wenjuan Li Peiqing Tong Department of Physics and Institute of Theoretical Physics Nanjing Normal University Nanjing 210046 People’s Republic of China Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing 210046 People’s Republic of China

The heat conductivity of nonperiodic quantum Ising chains whose ends are connected with heat baths at different temperatures are studied numerically by solving the Lindblad master equation. The chains are subjected to a uniform transverse field h, while the exchange coupling Jm between the nearest-neighbor spins takes the two values JA and JB arranged in Fibonacci, generalized Fibonacci, Thue-Morse, and period-doubling sequences. We calculate the energy-density profile and energy current of the resulting nonequilibrium steady states to study the heat-conducting behavior of finite but large systems. Although these nonperiodic quantum Ising chains are integrable, it is clearly found that energy gradients exist in all chains and the energy currents appear to scale as the system size 〈Q〉~Nα. By increasing the ratio of couplings, the exponent α can be modulated from α>−1 to α<−1 corresponding to the nontrivial transition from the abnormal heat transport to the heat insulator. The influences of the temperature gradient and the magnetic field to heat conduction have also been discussed.

关键词： HEAT conduction ISING model EQUATIONS FIBONACCI sequence THERMAL conductivity

A Travel Time Prediction Method for Urban Road Traffic Sensors Data

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A Travel Time Prediction Method for Urban Road Traffic Senso...

International Conference on Identification, Information and Knowledge in the Internet of Things (IIKI)

作者： Guangyu Zhu Kang Song Peng Zhang Ministry of Education Key Laboratory of System Control and Information Processing Shanghai China MOE Key Laboratory for Transportation Complex Systems- Theory and Technology Beijing Jiaotong University Beijing China Beijing Municipality Key Laboratory of Urban Traffic Operation Simulation and Decision Support Beijing China

Travel time parameters obtained from road traffic sensors data play an important role in traffic management practice. In this paper, a travel time analysis and prediction model was established for urban road traffic sensors data based on the change point analysis algorithm and ARIMA model. Firstly, time series of travel time parameters were clustered by using change point mining algorithm after traffic sensors data preprocessing. Then, a travel time prediction model was established based on ARIMA model. Finally, the model was verified with high accuracy through simulation by using multiple sets of data and analysis of its practicability was done.

关键词： Predictive models Data models Roads Time series analysis Detectors Analytical models

Energy cost and greenhouse gas emissions of a Chinese wind farm

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Procedia Environmental Sciences 2011年 5卷 25-28页

作者： Q. Yang G.Q. Chen Y.H. Zhao B. Chen Z. Li B. Zhang Z.M. Chen H. Chen State Key Laboratory of Turbulence and Complex Systems College of Engineering Peking University Beijing 100871 China China Hua Dian Corporation Beijing 100035 China State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China

Wind power is considered as one of the most promising renewable energy sources in China. Presented in this study is a life cycle analysis of energy performance and greenhouse gas emission for a typical wind farm in Guangxi, with different stages of manufacturing, transportation, and installation of mechanical components, operation and maintenance, and disassemble and disposal taken into account. Results show that the nonrenewable energy cost and greenhouse gas emission to generate 1 MJ of electricity for the grid are 0.046 MJ and 0.002 kg CO2 equivalent, respectively. In consideration of the dominant power generation technology of coal combustion in China, the nonrenewable energy saving brought about by the concerned wind farm is estimated at 1.22E+7GJ during its twenty year operating period, while the reduced greenhouse gas emissions are as much as 1.03E+06 ton CO2 equivalent. It is believed that this successful example can lend solid support to a future wide use of wind power in China.

关键词： Embodied energy analysis Greenhouse gas emission Wind farm China

Reanalysis of the most strange dibaryon within constituent quark models

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arXiv 2019年

作者： Huang, Hongxia Zhu, Xinmei Ping, Jialun Department of Physics Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing210023 China Department of Physics Yangzhou University Yangzhou225009 China

The most strange dibaryon ΩΩ with quantum numbers S = −6, I = 0, and JP = 0+, 1−, 2+, 3− is reanalyzed in the framework of quark delocalization color screening model (QDCSM) and chiral quark model (ChQM). The ΩΩ dibaryon with JP = 0+ is bound, and the one with other quantum numbers JP = 1−, 2+, 3− are all unbound in our calculation. The low-energy scattering phase shifts, the scattering length, and the effective range of the ΩΩ dibaryon with JP = 0+ also support the existence of such strange dibaryon. This dibaryon is showed to be a shallow bound state in QDCSM, while the binding energy becomes much larger in the ChQM by including the effect of the hidden-color channel coupling. And the scalar nonet meson-exchange in the ChQM also provides more attraction for the ΩΩ system. Experimental search for such most strange dibaryon will provide much information for understanding the hadron-hadron interactions in different quark models. Copyright © 2019, The Authors. All rights reserved.

关键词： Quantum theory

Search for doubly-heavy dibaryons in the quark-delocalization color-screening model

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arXiv 2021年

作者： Xia, Zhuocheng Fan, Saijun Zhu, Xinmei Huang, Hongxia Ping, Jialun Department of Physics Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing210023 China Department of Physics Yangzhou University Yangzhou225009 China

We perform a systemical investigation of the low-lying doubly-heavy dibaryon systems with strange S = 0, isospin I = 0, 1, 2 and the angular momentum J = 0, 1, 2, 3 in the quark de- localization color screening model. We find the effect of channel-coupling cannot be neglected in the study of the multi-quark systems. Due to the heavy flavor symmetry, the results of the doubly- charm and doubly-bottom dibaryon systems are similar with each other. Both of them have three bound states, the quantum numbers of which are IJ = 00, IJ = 02 and IJ = 13, respectively. The energies are 4554 MeV, 4741 MeV, and 4969 MeV respectively for the doubly-charm systems and 11219 MeV, 11416 MeV, and 11633 MeV respectively for the doubly-bottom dibaryon systems. Besides, six resonance states are obtained, which are IJ = 00 NΞccand NΞbbwith resonance mass of 4716 MeV and 11411 MeV respectively, IJ = 11 NΞ∗ccand NΞ∗bbwith resonance mass of 4757 MeV and 11432 MeV respectively, and IJ = 12 ΣcΣ∗cand ΣbΣ∗bwith resonance mass of 4949 MeV and 11626 MeV respectively. All these heavy dibaryons are worth searching for on experiments, although it will be a challenging work. © 2021, CC BY.

关键词： Resonance

Is d∗(2380) a compact hexaquark state?

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arXiv 2023年

作者： Pan, Manying Zhu, Xinmei Ping, Jialun Department of Physics Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing210023 China Department of Physics Yangzhou University Yangzhou225009 China

The most fascinating dibaryon in the non-strange quark sector is d∗(2380), which was reported by WASA-at-COSY Collaboration and confirmed by A2@MAMI Collaboration. The reported mass and decay width are M ≈ 2.37 GeV, Γ ≈ 70 MeV and the quantum numbers are IJP = 03+. The structure of d∗(2380) is still in controversy. In the present calculation, the powerful method in few-body system, Gaussian Expansion Method (GEM) is employed to explore the structure of d∗(2380) in the framework of constituent quark models without assuming the presupposed structure. The results show that the radius of d∗(2380) is around 0.8 fm, it is a very compact object. Because of the compact structure, the color singlet-singlet component has a large overlap with the color octet-octet one, two colorless, large overlapped ∆s dominate the state is possible. Copyright © 2023, The Authors. All rights reserved.

关键词： Color

Reputation-Based Conditional Investment Enhances the Evolution of Cooperation in Spatial Public Goods Game

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Reputation-Based Conditional Investment Enhances the Evoluti...

International Conference on Identification, Information and Knowledge in the Internet of Things (IIKI)

作者： Hong Ding Lin Cao Hongjun Qiu Zhangbing Zhou Lei Shu Yizhi Ren Key Laboratory of Complex Systems Modeling and Simulation Ministry of Education China Hangzhou Dianzi University Hangzhou China School of Computer Science and Technologv Hangzhou Dianzi University Hangzhou China School of Information Engineering China University of Geosciences Beijing China Guangdong Petrochemical Equipment Fault Diagnosis Key Laboratory Guangdong University of Petrochemical Technology Maoming China

Most previous studies involving public goods games are investigated under a simplifying assumption that participators are compulsive in collective interactions and contribute unconditionally to the public pool. Nevertheless, how the conditional investment mechanism based on individual's reputation affects the evolution of cooperation in structured populations is still unclear. Here we introduce a reputation-based conditional investment rule for constituting participant groups into spatial threshold public goods game, where the public goods game can be conducted only if the participant number is not less than the threshold parameter. Interestingly, we find that large threshold parameter results in the optimal environment for cooperators' viability.

关键词： Games Investment Sociology Statistics Lattices Evolution (biology) Fault diagnosis