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Prospects for cosmological research with the FAST array: 21-cm intensity mapping survey observation strategies

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arXiv 2024年

作者： Pan, Jun-Da Wu, Peng-Ju Du, Guo-Hong Li, Yichao Zhang, Xin Liaoning Key Laboratory of Cosmology and Astrophysics College of Sciences Northeastern University Shenyang110819 China MOE Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang110819 China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang110819 China

Precise cosmological measurements are essential for understanding the evolution of the universe and the nature of dark energy. The Five-hundred-meter Aperture Spherical Telescope (FAST), the most sensitive single-dish radio telescope, has the potential to provide the precise cosmological measurements through neutral hydrogen 21 cm intensity mapping sky survey. This paper primarily explores the potential of technological upgrades for FAST in cosmology. The most crucial upgrade begins with equipping FAST with a wide-band receiver (0 0) = 0.09 and σ(wa) = 0.33. Copyright © 2024, The Authors. All rights reserved.

关键词： Dark energy

ETO Meets Scheduling: Learning Key Knowledge from Single-Objective Problems to Multi-Objective Problem

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ETO Meets Scheduling: Learning Key Knowledge from Single-Obj...

2021 China Automation Congress, CAC 2021

作者： Xu, Wendi Wang, Xianpeng College of Information Science and Engineering Northeastern University China Key Laboratory of Data Analytics and Optimization for Smart Industry Ministry of Education China

ISBN: (纸本)9781665426473

Evolutionary transfer optimization(ETO) serves as "a new frontier in evolutionary computation research", which will avoid zero reuse of experience and knowledge from solved problems in traditional evolutionary computation. In schedule-ing applications via ETO, a highly competitive "meeting" framework between them could be constituted towards both intelligent scheduling and green scheduling, especially for carbon neutrality within the context of China. To the best of our knowledge, our study on scheduling here, is the 1st work of ETO for complex optimization when multi-objective problem "meets" single-objective problems in combinatorial case (not multitasking optimization). More specifically, key knowledge like positional building blocks clustered, could be learned and transferred for permutation flow shop scheduling problem (PFSP). Empirical studies on well-studied benchmarks validate relatively firm effectiveness and great potential of our proposed ETO-PFSP framework. © 2021 IEEE

关键词： data analytics

Revisiting holographic dark energy from the perspective of multi-messenger gravitational wave astronomy: future joint observations with short gamma-ray bursts

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arXiv 2024年

作者： Han, Tao Li, Ze Zhang, Jing-Fei Zhang, Xin Liaoning Key Laboratory of Cosmology and Astrophysics College of Sciences Northeastern University Shenyang110819 China MOE Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang110819 China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang110819 China

The advent of third-generation (3G) gravitational-wave (GW) detectors opens new opportunities for multi-messenger observations of binary neutron star merger events, holding significant potential for probing the history of cosmic expansion. In this paper, we investigate the holographic dark energy (HDE) model by using the future GW standard siren data observed from the 3G GW detectors and the short γ-ray burst THESEUS-like detector joint observations. We find that GW data alone can achieve a relatively precise estimation of the Hubble constant, with precision of 0.2%–0.6%, but its ability to constrain other cosmological parameters remains limited. Nonetheless, since the GW data can break parameter degeneracies generated by the mainstream EM observations, CMB + BAO + SN (CBS), GW standard sirens play a crucial role in enhancing the accuracy of parameter estimation. With the addition of GW data to CBS, the constraints on cosmological parameters H0, c and Ωm can be improved by 63%–88%, 27%–44% and 55%–70%. In summary, observations of GW standard sirens from 3G GW detectors could be pivotal in helping solve the Hubble tension and probe the fundamental nature of dark energy. Copyright © 2024, The Authors. All rights reserved.

关键词： Dark energy

Robust inference of gravitational wave source parameters in the presence of noise transients using normalizing flows

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arXiv 2024年

作者： Xiong, Chun-Yu Sun, Tian-Yang Zhang, Jing-Fei Zhang, Xin Liaoning Key Laboratory of Cosmology and Astrophysics College of Sciences Northeastern University Shenyang110819 China MOE Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang110819 China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang110819 China

Gravitational wave (GW) detection is of paramount importance in fundamental physics and GW astronomy, yet it presents formidable challenges. One significant challenge is the removal of noise transient artifacts known as "glitches", which greatly impact the search and identification of GWs. Recent research has achieved remarkable results in data denoising, often using effective modeling methods to remove glitches. However, for glitches from uncertain or unknown sources, current methods cannot completely eliminate them from the GW signal. In this work, we leverage the inherent robustness of machine learning to obtain reliable posterior parameter distributions directly from GW data contaminated by glitches. Our network model provides reasonable and rapid parameter inference even in the presence of glitches, without needing to remove them. We also investigate various factors affecting the rationality of parameter inference in our normalizing flow network, including glitch and GW parameters. The results demonstrate that the normalizing flow can reasonably infer the source parameters of GWs even with unknown contamination. We find that the nature of the glitch itself is the only factor that can affect the rationality of the inferred results. With improvements to our model, we anticipate accelerating the localization of electromagnetic counterparts and providing priors for more accurate deglitching, thereby speeding up subsequent data processing procedures. Copyright © 2024, The Authors. All rights reserved.

关键词： data handling

A Thousand-Hand Bodhisattva: Emergent Abilities of Artificial General Intelligence Via Single- Objective to Multi-Objective optimization

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SSRN

SSRN 2024年

作者： Xu, Wendi Ming, Zhang Shengchun, Zheng National Frontier Sciences Center for Industrial Intelligence and Systems Optimization Ministry of Education China College of Information Science and Engineering Northeastern University Key Laboratory of Data Analytics and Optimization for Smart Industry Ministry of Education China Key Laboratory of Data Analytics and Optimization for Smart Industry Ministry of Education China Xinjiang Astronomical Observatory Chinese Academy of Sciences China Key Laboratory for Radio Astronomy Chinese Academy of Sciences Nanjing China University of Chinese Academy of Sciences China Fujian Coastal Environmental Monitoring Station China

Towards artificial general intelligence, emergent abilities of large language models (LLMs) are observed wildly especially for well-known GPTs, which are due to scaling up primarily along three factors: training computation, model parameters, and dataset size. Scaling up makes emergence. Inspired by the insights for LLMs case, we scale up the number of auxiliary tasks (from 2 to many) to boost the core task for the model of single-objective to multi-objective optimization (SMO) in evolutionary transfer optimization (ETO), therefore achieve a new version of SMO in the open benchmarks of vehicle routing problems, permutation flow shop scheduling problem and travel salesman problem. We name the new SMO armed with transfer core as a "Thousand-Hand Bodhisattva" with many arms or hands and analyze its emergent abilities. © 2024, The Authors. All rights reserved.

关键词： Multiobjective optimization

The Connes-Chamseddine cycle and the noncommutative integral

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arXiv 2024年

作者： Wu, Tong Wang, Yong Department of Mathematics Northeastern University Shenyang110819 China Key Laboratory of Data Analytics and Optimization for Smart Industry Ministry of Education Northeastern University Liaoning Shenyang110819 China School of Mathematics and Statistics Northeast Normal University Changchun130024 China

In [5], Connes and Chamseddine defined a cycle in the general framework of noncommutative geometry. They computed this cycle for the Dirac operator on 4-dimensioanl manifolds. We propose a way to study the Connes-Chamseddine cycle from the viewpoint of the noncommutative integral on 6-dimensional manifolds in this paper. Furthermore, we compute several interesting noncommutative integral defined in [8] by the normal coodinated way on n-dimensional manifolds. As a corollary, the Connes-Chamseddine cycle on 6-dimensional manifolds is obtained. Copyright © 2024, The Authors. All rights reserved.

关键词： Choquet integral

Geometry-aided Underwater 3D Mapping Using Side-scan Sonar

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Geometry-aided Underwater 3D Mapping Using Side-scan Sonar

IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)

作者： Yiqiao Yang Chenglin Pang Chengdong Wu Zheng Fang Faculty of Robot Science and Engineering Northeastern University Shenyang China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang China Key Laboratory of Data Analytics and Optimization for Smart Industry Ministry of Education Northeastern University Shenyang China

ISBN: (数字)9798350377705

ISBN: (纸本)9798350377712

In recent years, the interest in underwater exploration with Autonomous Underwater Vehicles (AUVs) equipped with side-scan sonars (SSS) has grown considerably. However, state-of-the-art SSS Simultaneous Localization and Mapping (SLAM) systems encounter challenges in data association across large viewpoint changes. Additionally, these systems assume that the seabed is a flat surface, leading to significant mapping error in uneven underwater terrains. To address these challenges, we propose a framework that leverages the side-scan sonar geometry to facilitate data association and improve mapping accuracy. The framework begins with a preprocessing module that extracts feature points and provides initial estimates of the elevation angles of the landmarks. Then, a non-consecutive data association module applies epipolar line search to establish correspondences between the current and historical frames. Finally, the mapping module uses side-scan sonar bundle adjustment to recover the positions of the landmarks. The proposed method is evaluated using an underwater terraced fields dataset. Our method achieves over 90% matching rate and reduces the average mapping error from 3.799 to 0.134.

关键词： Geometry Bundle adjustment Autonomous underwater vehicles Simultaneous localization and mapping Accuracy Geometric modeling Feature extraction Side-scan sonar optimization Intelligent robots

Model-independent H0 within FLRW: Joint constraints from GWTC-3 standard sirens and strong lensing time delays

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arXiv 2025年

作者： Song, Ji-Yu Qi, Jing-Zhao Zhang, Jing-Fei Zhang, Xin Key Laboratory of Cosmology and Astrophysics Department of Physics College of Sciences Northeastern University Liaoning Province Shenyang110819 China Key Laboratory of Data Analytics and Optimization for Smart Industry Ministry of Education Northeastern University Shenyang110819 China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang110819 China

The Hubble tension has emerged as a critical crisis in cosmology, with the cause remaining unclear. Determining the Hubble constant (H0) independently of cosmological models and distance ladders will help resolve this crisis. In this letter, we for the first time use 47 gravitational-wave (GW) standard sirens from the third Gravitational-Wave Transient Catalog to calibrate distances in the strong lensing system, RXJ1131-1231, and constrain H0 through the distance-sum rule, with minimal cosmological assumptions. We assume that light propagation over long distances is described by the Friedmann-Lemaitre-Robertson-Walker metric and that geometrical optics holds, but we do not need to assume the universe’s contents or the theory of gravity on cosmological scales. Fixing ΩK = 0, we obtain H0 = 73.22+5−5.9543 km s−1 Mpc−1 and H0 = 70.40+8−5.0360 km s−1 Mpc−1 by using the deflector galaxy’s mass model and kinematic measurements to break mass-sheet transform, respectively. When ΩK is not fixed, the central value of H0 increases further. We find that our results are still dominated by statistical errors, and at the same time, we notice the great potential of using GW dark sirens to provide calibration, owing to their higher redshifts. When using 42 binary black holes and RXJ1131-1231, we obtain a 8.46% H0 constraint precision, which is better than that from the bright siren GW170817 using the Hubble law by about 40%. In the future, as the redshift range of GW dark sirens increases, more and more SGLTDs can be included, and we can achieve high-precision, model-independent measurements of H0 without the need for GW bright sirens. Copyright © 2025, The Authors. All rights reserved.

关键词： Cosmology

Low-cost surface modification of a biomedical Zr-2.5Nb alloy fabricated by electron beam melting

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Journal of Materials Science & Technology 2023年第12期143卷 178-188页

作者： Caixu Wang Xiaoli Zhao Shujun Li Lu Liu Deliang Zhang Mitsuo Niinomi School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key Laboratory of Data Analytics and Optimization for Smart Industry(Ministry of Education) Northeastern UniversityShenyang 110819China Tianjin Key Laboratory of Bone Implants Interface Functionalization and Personalization Tianjin 300190China Institute for Materials Research Tohoku UniversitySendaiMiyagi 9808577Japan Division of Materials and Manufacturing Science Graduate School of EngineeringOsaka UniversityOsaka 565-0871Japan Department of Materials Science and Engineering Graduate School of Science and TechnologyMeijo UniversityNagoya 468-8502Japan Faculty of Chemistry Materials and BioengineeringKansai UniversityOsaka 564-860Japan

The Zr-2.5Nb alloy with a fine microstructure consisting ofαlaths was successfully prepared by electron beam melting(EBM).The thermal oxidation behaviors and kinetics of the as-built,and the EBM-built and hot isostatically pressed(HIPed)Zr-2.5Nb materials in a temperature range of 450-600°C were in-vestigated and compared with those of the alloy prepared by conventional casting and *** was found that the oxidation kinetics of the as-built and the forged materials followed the parabolic rate law during isothermal oxidation at 550°C,but the HIPed materials exhibited a parabolic-to-linear kinetic transition,suggesting that the larger grain sizes enhanced the *** oxide layers of all materials were composed of a large fraction of monoclinic zirconia phase(m-ZrO_(2))and a small fraction of tetrago-nal zirconia phase(t-ZrO_(2)),and transformed from t-ZrO_(2)to m-ZrO_(2)with increasing oxidation *** surface hardness of the as-built,the forged and the HIPed materials increased from 215,204,and 188 HV before oxidation to 902,1070,and 1137 HV after oxidation,*** cross-sections of the materi-als showed the presence of micropores and microcracks inside the oxide layers with thicknesses ranging from 4 to 8μ*** the oxidation temperature of 600°C and oxidation time duration of 3 h,a dense black m-ZrO_(2)oxide layer with smooth surface and 902 HV hardness was obtained on the EBM as-built Zr-2.5Nb materials.

关键词： Zr-2.5Nb alloy Electron beam melting Thermal oxidation Oxidation behaviors and kinetics Grain size