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arXiv 2023年

作者： Li, Yichao Wang, Yougang Deng, Furen Yang, Wenxiu Hu, Wenkai Liu, Diyang Zhao, Xinyang Zuo, Shifan Shu, Shuanghao Li, Jixia Timbie, Peter Ansari, Réza Perdereau, Olivier Stebbins, Albert Wolz, Laura Wu, Fengquan Zhang, Xin Chen, Xuelei College of Sciences Northeastern University Shenyang110819 China National Astronomical Observatories Chinese Academy of Sciences Beijing100101 China School of Astronomy and Space Science University of Chinese Academy of Sciences Beijing100049 China Key Laboratory of Radio Astronomy and Technology Chinese Academy of Sciences A20 Datun Road Chaoyang District Beijing100101 China Aix Marseille Univ CNRS CNES LAM Marseille France Australia Department of Physics University of Wisconsin – Madison MadisonWI53706 United States Université Paris-Saclay Université Paris Cité CEA CNRS AIM Gif-sur-Yvette91191 France Université Paris-Saclay CNRS IN2P3 IJCLab Orsay91405 France Fermi National Accelerator Laboratory P.O. Box 500 BataviaIL60510 United States Jodrell Bank Centre for Astrophysics Department of Physics & Astronomy The University of Manchester ManchesterM13 9PL United Kingdom National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang110819 China Key Laboratory of Data Analytics and Optimization for Smart Industry Ministry of Education Northeastern University Shenyang110819 China

This work presents the initial results of the drift-scan observation for the neutral hydrogen (Hi) intensity mapping survey with the Five-hundred-meter Aperture Spherical radio Telescope (FAST). The data analyzed in this work were collected in night observations from 2019 through 2021. The primary findings are based on 28 hours of drift-scan observation carried out over seven nights in 2021, which covers 60 deg2 sky area. Our main findings are: (i) Our calibration strategy can successfully correct both the temporal and bandpass gain variation over the 4-hour drift-scan observation. (ii) The continuum maps of the surveyed region are made with frequency resolution of 28 kHz and pixel area of 2.95 arcmin2. The pixel noise levels of the continuum maps are slightly higher than the forecast assuming Tsys = 20 K, which are 36.0 mK (for 10.0 s integration time) at the 1050–1150 MHz band, and 25.9 mK (for 16.7 s integration time) at the 1323–1450 MHz band, respectively. (iii) The flux-weighted differential number count is consistent with the NRAO-VLA Sky Survey (NVSS) catalog down to the confusion limit ∼ 7 mJy/beam−1. (iv) The continuum flux measurements of the sources are consistent with that found in the literature. The difference in the flux measurement of 81 isolated NVSS sources is about 6.3%. Our research offers a systematic analysis for the FAST Hi intensity mapping drift-scan survey and serves as a helpful resource for further cosmology and associated galaxies sciences with the FAST drift-scan survey. Copyright © 2023, The Authors. All rights reserved.

关键词： data handling

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optimization of the raw material field layout for iron-steel enterprise

Optimization of the raw material field layout for iron-steel...

引用

作者： Wenbo Liu Yuehong Kong Department of Logistics Management Liaoning Provincial College of Communications Key Laboratory of Data Analytics and Optimization for Smart Industry(Northeastern University)

This paper studies a short-term layout optimization problem with the raw material field for iron-steel *** raw material field is a centralized storage place and distribution unit of various raw materials such as iron ore,which plays a significant role in the iron front logistics for iron and steel *** the stacking of raw materials is reasonable or not directly affects the logistics efficiency and logistics cost of raw materials for iron-steel *** on the status and basic information of the raw materials,storage space of the field shall be made full use of to allocate the optimal position for each type of raw *** achieve this goal,a mixed integer programming(MIP) model is developed,which is purposed to minimize the transportation cost and the loss of *** solution compares favorably with the current practice in the iron-steel enterprises.

关键词： workshop optimization of the raw material field layout for iron-steel enterprise

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Holographic p-wave superconductivity from higher derivative theory

arXiv

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arXiv 2020年

作者： Liu, Yan Fu, Guoyang Li, Hai-Li Wu, Jian-Pin Zhang, Xin College of Sciences MOE Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang110819 China Center for Gravitation and Cosmology College of Physical Science and Technology Yangzhou University Yangzhou225009 China School of Aeronautics and Astronautics Shanghai Jiao Tong University Shanghai200240 China

We construct a holographic SU(2) p-wave superconductor model with Weyl corrections. The high derivative (HD) terms do not seem to spoil the generation of the p-wave superconducting phase. We mainly study the properties of AC conductivity, which is absent in holographic SU(2) p-wave superconductor with Weyl corrections. The conductivities in superconducting phase exhibit obvious anisotropic behaviors. Along y direction, the conductivity σyy is similar to that of holographic s-wave superconductor. The superconducting energy gap exhibits a wide extension. For the conductivity σxx along x direction, the behaviors of the real part in the normal state are closely similar to that of σyy. However, the anisotropy of the conductivity obviously shows up in the superconducting phase. A Drude-like peak at low frequency emerges in Reσxx once the system enters into the superconducting phase, regardless of the behaviors in normal state. Copyright © 2020, The Authors. All rights reserved.

关键词： Holography

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A novel PSDE algorithm for multi-objective optimization

A novel PSDE algorithm for multi-objective optimization

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第三十八届中国控制会议

作者： Meiling Xu Hongxin Dong Zaidi Ji Yiwen Wang Key laboratory of Data Analytics and Optimization for Smart Industry Ministry of Education Northeastern University Faculty of Electronic Information and Electrical Engineering Dalian University of Technology

Differential evolution for multi-objective optimization is a useful and straightforward evolutionary optimization algorithm. Since the algorithm randomly searches in problem space, it may get into trouble when we adapt it to solve multi-objective problems. With regard to the limitation of DE, we propose a new algorithm PSDE to solve multi-objective functions based on the PSO operator and DE operator. In this algorithm, we utilize DE operator to promote the uniform spread of solutions and use PSO operator to obtain good local search ability by retaining the best solutions obtained so far. Experimental results on a set of benchmark test functions sustain the effectiveness of the proposed algorithm.

关键词： Differential evolution multi-objective optimization particle swarm optimization

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Forecast for cosmological parameter estimation with gravitational-wave standard siren observation from the Cosmic Explorer

arXiv

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arXiv 2020年

作者： Jin, Shang-Jie He, Dong-Ze Xu, Yidong Zhang, Jing-Fei Zhang, Xin Department of Physics College of Sciences Northeastern University Shenyang110819 China Key Laboratory for Computational Astrophysics National Astronomical Observatories Chinese Academy of Sciences Beijing100101 China Ministry of Education's Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang110819 China Center for High Energy Physics Peking University Beijing100080 China

The third-generation ground-based gravitational-wave (GW) detector, Cosmic Explorer (CE), is scheduled to start its observation in the 2030s. In this paper, we make a forecast for cosmological parameter estimation with gravitational-wave standard siren observation from the CE. We use the simulated GW standard siren data of CE to constrain the ΛCDM, wCDM and CPL models. We combine the simulated GW data with the current cosmological electromagnetic observations including the latest cosmic microwave background anisotropies data from Planck, the optical baryon acoustic oscillation measurements, and the type Ia supernovae observation (Pantheon compilation) to do the analysis. We find that the future standard siren observation from CE will improve the cosmological parameter estimation to a great extent, since the future GW standard siren data can well break the degeneracies generated by the optical observations between various cosmological parameters. We also find that the CE's constraining capability on the cosmological parameters is slightly better than that of the same-type GW detector, the Einstein Telescope. In addition, the synergy between the GW standard siren observation from CE and the 21 cm emission observation from SKA is also discussed. Copyright © 2020, The Authors. All rights reserved.

关键词： Gravity waves

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Impacts of dark energy on constraining neutrino mass after Planck 2018

arXiv

引用

arXiv 2020年

作者： Zhang, Ming Zhang, Jing-Fei Zhang, Xin Department of Physics College of Sciences Northeastern University Shenyang110819 China Ministry of Education’s Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang110819 China Center for High Energy Physics Peking University Beijing100080 China Center for Gravitation and Cosmology Yangzhou University Yangzhou225009 China

Considering the mass splittings of three active neutrinos, we investigate how the nature of dark energy affects the cosmological constraints on the total neutrino mass P mν using the latest cosmological observations. In this paper, some typical dark energy models, including ΛCDM, wCDM, CPL, and HDE models, are discussed. In the analysis, we also consider the effects from the neutrino mass hierarchies, i.e., the degenerate hierarchy (DH), the normal hierarchy (NH), and the inverted hierarchy (IH). We employ the current cosmological observations to do the analysis, including the Planck 2018 temperature and polarization power spectra, the baryon acoustic oscillations (BAO), the type Ia supernovae (SNe), and the Hubble constant H0 measurement. In the ΛCDM+P mν model, we obtain the upper limits of the neutrino mass P mν Copyright © 2020, The Authors. All rights reserved.

关键词： Acoustic intensity measurement

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Constraints on neutrino mass in the scenario of vacuum energy interacting with cold dark matter after Planck 2018

arXiv

引用

arXiv 2020年

作者： Li, Hai-Li Zhang, Jing-Fei Zhang, Xin Department of Physics College of Sciences Northeastern University Shenyang110819 China Ministry of Education’s Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang110819 China Center for High Energy Physics Peking University Beijing100080 China Center for Gravitation and Cosmology Yangzhou University Yangzhou225009 China

In this work, we investigate the constraints on the total neutrino mass in the scenario of vacuum energy interacting with cold dark matter (abbreviated as IΛCDM) by using the latest cosmological observations. We consider four typical interaction forms, i.e., Q = βHρde, Q = βHρc, Q = βH0ρde, and Q = βH0ρc, in the IΛCDM scenario. To avoid the large-scale instability problem in interacting dark energy models, we employ the extended parameterized post-Friedmann method for interacting dark energy to calculate the perturbation evolution of dark energy in these models. The observational data used in this work include the cosmic microwave background (CMB) measurements from the Planck 2018 data release, the baryon acoustic oscillation (BAO) data, the type Ia supernovae (SN) observation (Pantheon compilation), and the 2019 local distance ladder measurement of the Hubble constant H0 from the Hubble Space Telescope. We find that, compared with those in the ΛCDM+P mν model, the constrains on P mν are looser in the four IΛCDM+P mν models. When considering the three mass hierarchies of neutrinos, the constraints on P mν are tightest in the degenerate hierarchy case and loosest in the inverted hierarchy case. In addition, in the four IΛCDM+P mν models, the values of coupling parameter β are larger using the CMB+BAO+SN+H0 data combination than that using the CMB+BAO+SN data combination, and β > 0 is favored at more than 1σ level when using CMB+BAO+SN+H0 data combination. The issue of the H0 tension is also discussed in this paper. We find that, compared with the ΛCDM+P mν model, the H0 tension can be alleviated in the IΛCDM+P mν model to some extent. Copyright © 2020, The Authors. All rights reserved.

关键词： Acoustic intensity measurement

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A novel method of measuring cosmological distances using broad-line regions of quasars

arXiv

引用

arXiv 2020年

作者： Li, Hong Zhang, Xin Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing100049 China Department of Physics College of Sciences Northeastern University Shenyang110819 China Ministry of Education’s Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang110819 China Center for High Energy Physics Peking University Beijing100080 China Center for Gravitation and Cosmology Yangzhou University Yangzhou225009 China

Our ancestors, such as Cro-Magnon, always looked up at the stars and wished to understand the mysteries of the universe, but their view of the universe was probably quite simple: the stars are inlaid on the inner surface of the sky, and they are very small. However, now we know that stars and galaxies are actually extremely huge, and they look small because they are too far away from us. This indicates that the measurement of cosmological distance is always very important in the study of the universe. Due to the expansion of the cosmos, the stars we see are actually what they used to be. The wavelength of light emitted from a star becomes longer due to the expansion of the universe, which is called "redshift of light". The larger the redshift, the older is the star. If we can measure both the distances and redshifts of stars (luminous objects), we can then establish a relationship between distance and redshift, from which the information of cosmic expansion history can be obtained. Actually, the measurement of the expansion history of the universe can answer the fundamental questions about the cosmos, such as its age, geometry, composition, and so forth. Copyright © 2020, The Authors. All rights reserved.

关键词： Stars

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Texture and microstructure evolution of 321 austenitic stainless steel ultra-thin strip during asynchronous rolling

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IOP Conference Series: Materials Science and Engineering 2020年第1期892卷

作者： Jingqi Chen Liuqing Yang Xianlei Hu Xianghua Liu State Key Laboratory of Rolling and Automation Northeastern University Shengyang 110819 China Key Laboratory of Data Analytics and Optimization for Smart Industry (Northeastern University) Ministry of Education Shengyang 110819 China

This paper studied the evolution of texture and microstructure of 321 austenitic stainless steel ultra-thin strip during asynchronous rolling. Experimental results show that during the process of asynchronous rolling, the martensitic structure mainly forms such kinds of texture, as {111} <110> Z texture, {111} <112> Y texture, {001} <110> R-CubeND texture, {112} <110> Cu texture, and {110} <110> Goss texture. With the increase of deformation, the strengths of {111} <112> Y texture, {001} <110> R-CubeND texture, {112} <110> Cu texture, and {110} <110> Goss texture increase first and then decrease. In the early stage of rolling, dislocation slip is the main plastic deformation, followed by deformation twins in the high strain region, which prevents further dislocation slip. When the rolling pressure rate is greater than 50%, the deformation induces rapid growth in the content of the martensite, with the continued nucleation and growth of the deformation twins.

关键词：

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Microstructure and mechanical properties of solid state recycled 4Cr5MoSiV (H11) steel prepared by powder metallurgy

Results in Materials

引用

Results in Materials 2021年 10卷

作者： Bhatta, Gyanendra De Los Santos Valladares, Luis Liu, Xinggang Ma, Zhaojun Bustamante Domínguez, A.G. Moreno, N.O. Espinoza Suarez, S.M. Barnes, C.H.W. Zhang, Deliang School of Materials Science and Engineering Northeastern University Liaoning Shenyang 110819 China Key Laboratory of Data Analytics and Optimization for Smart Industry (Ministry of Education) Northeastern University Shenyang 110819 China Laboratorio de Ceramicos y Nanomaterailes Facultad de Ciencias Físicas Universidad Nacional Mayor de San Marcos Ap. Postal 14-0149 Lima Peru Cavendish Laboratory Department of Physics University of Cambridge UK Cambridge CB3 0HE United Kingdom Departamento de Física Universidade Federal de Sergipe SE São Cristóvão 49100- 000 Brazil

4Cr5MoSiV (H11) steel machining chips were crushed to a powder and then consolidated into discs by hot pressing under various consolidation parameters. The discs were subjected to modified spheroidizing annealing treatment, and their evolved microstructure, tensile mechanical properties and fracture behavior were studied. The microstructure consisted of α−Fe as a matrix, together with heterogeneously distributed non metallic inclusions from the chip-crushing step and precipitated secondary phases. The yield strength, fracture strength and elongation to fracture of the consolidated discs were determined to be in the range of 215∼264 MPa, 344∼415 MPa and 1.2∼2.6%, respectively. The strength of the recycled H11 steel was comparable with that of the ingot metallurgy (IM) H11 steel, but the tensile ductility of the former was significantly lower than that of the latter, being mainly caused by the fracture of the non-metallic inclusions along with the hard secondary phase particles in the IM H11 steel which leads to premature fracture of the samples. The Vickers hardness of the samples were in the range of 144∼194 HV being comparable to that of the IM counterpart. Factographs of the fracture surface demonstrated that the tensile test specimens fractured in a brittle fracture mode. © 2021 The Author(s)

关键词： Brittle fracture H11 Steel Microstructure Modified spheroidizing Solid state recycling Tensile properties

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