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arXiv 2024年

作者： Xiao, Si-Ren Shao, Yue Wang, Ling-Feng Song, Ji-Yu Feng, Lu Zhang, Jing-Fei Zhang, Xin Liaoning Key Laboratory of Cosmology and Astrophysics College of Sciences Northeastern University Shenyang110819 China School of Physics and Optoelectronic Engineering Hainan University Haikou570228 China College of Physical Science and Technology Shenyang Normal University Shenyang110034 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

Recently, several pulsar timing array (PTA) projects have detected evidence of the existence of a stochastic gravitational wave background (SGWB) in the nanohertz frequency band, providing confidence in detecting individual supermassive black hole binaries (SMBHBs) in the future. Nanohertz GWs emitted by inspiraling SMBHBs encode the luminosity distances of SMBHBs. They can serve as dark sirens to explore the cosmic expansion history via a statistical method to obtain the redshift information of GW sources’ host galaxies using galaxy catalogs. The theoretical analysis of the dark siren method relies on the modeling of the population of SMBHBs. Using a population model consistent with the latest SGWB observations is essential, as the SGWB provides significant information about the distribution of SMBHBs. In this work, we employ a quasar-based model, which can self-consistently account for the SGWB amplitude, to estimate the population of SMBHBs. We constrain the Hubble constant using the mock GW data from different detection cases of PTAs in the future. Our results show that a PTA consisting of 100 pulsars with a white noise level of 20 ns could measure the Hubble constant with a precision close to 1% over a 10-year observation period, and a PTA with 200 pulsars may achieve this goal over a 5-year observation period. The results indicate that modeling the SMBHB population significantly influences the analysis of dark sirens, and SMBHB dark sirens have the potential to be developed as a valuable cosmological probe. Copyright © 2024, The Authors. All rights reserved.

关键词： White noise

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Improving cosmological parameter estimation with the future gravitational-wave standard siren observation from the Einstein Telescope

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Physical Review D 2019年第6期99卷 063510-063510页

作者： Xuan-Neng Zhang Ling-Feng Wang Jing-Fei Zhang Xin Zhang Department of Physics College of Sciences Northeastern University Shenyang 110819 China Ministry of Education Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Shenyang 110819 China Center for High Energy Physics Peking University Beijing 100080 China Center for Gravitation and Cosmology Yangzhou University Yangzhou 225009 China

Detection of gravitational waves produced by the merger of binary compact objects could provide an independent way for measuring the luminosity distance to the gravitational-wave burst source, indicating that gravitational-wave observation, combined with observation of electromagnetic counterparts, can provide “standard sirens” for investigating the expansion history of the Universe in cosmology. In this work, we wish to investigate how the future gravitational-wave standard siren observations would break the parameter degeneracies existing in the conventional optical observations and how they help improve the parameter estimation in cosmology. We take the third-generation ground-based gravitational-wave detector, the Einstein Telescope, as an example to make an analysis. By simulating 1000 events data in the redshift range between 0 and 5 based on the ten-year observation of the Einstein Telescope, we find that the gravitational-wave data could largely break the degeneracy between the matter density and the Hubble constant, thus significantly improving the cosmological constraints. We further show that the constraint on the equation-of-state parameter of dark energy could also be significantly improved by including the gravitational-wave data in the cosmological fit.

关键词： Cosmological parameters

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A Synchronous and Accurate Detection Method for Gas Pipeline Leakage Position and Flow Rate Based on Double Fiber Bragg Gratings

SSRN

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SSRN 2022年

作者： Wang, Bo-Yuan Yuan, Zhen-Yu Meng, Fan-Li Li, Yu-Dong College of Information Science and Engineering Northeastern University Shenyang110819 China Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology Qinhuangdao066004 China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang110819 China Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Ministry of Education Shenyang110819 China

Fast and accurate detection of pipeline leaks plays an important role in reducing economic losses and ensuring the safety of personnel. However, for the two important indicators of gas pipeline detection, how to effectively detect the leakage location and leakage rate simultaneously is a serious challenge. In this paper, we present an innovative optical fiber detection method based on double fiber Bragg gratings (FBGs) string to solve this problem. Combined with the theory of material mechanics and fluid mechanics, the binary equations are derived as the demodulation formula. In the detection, the corresponding physical quantities can be calculated by substituting the center wavelength of the two FBGs after drift. The experiments demonstrate that this sensor's gas flow rate sensitivity in different positions can be up to 376.67 pm·s/m. Meanwhile, at the same flow rate and different leakage positions, the sensor has sensitive symmetrical performance. The error results manifest that the velocity error is not more than 0.13 m/s, and the relative position detection error is not more than 0.167%. Overall, besides the extended measurement range and excellent linearity, our method also has the advantages of low production cost, simple structure and ease of production, which is more suitable for gas pipeline health monitoring in the future. © 2022, The Authors. All rights reserved.

关键词： Fiber Bragg gratings

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The Enhanced N-Butanol Gas Sensing Properties Based on Perovskite-Type Znsno3 Nanoflowers

SSRN

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SSRN 2024年

作者： Meng, Fanli Zhou, Fangling Mu, Zhuangzhuang Yuan, Zhenyu Zhang, Renze Li, Yudong Zhu, Hongmin Yan, Xin College of Information Science and Engineering Northeastern University Shenyang110819 China Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology Qinhuangdao066004 China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang110819 China Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Ministry of Education Shenyang110819 China

N-butanol is a volatile organic compound (VOC) that is harmful to human health, and the development of gas sensors for n-butanol vapor detection is necessary. In this work, the nanoflowers-like ZnSnO3 was synthesized via a one-step hydrothermal route followed by an annealing process. The results revealed that optimizing the hydrothermal time to 12 hours resulted in ZnSnO3-2 exhibiting the highest gas response (40.48) towards 100ppm n-butanol at 275°C, boasting a detection limit of 500 ppb. Furthermore, ZnSnO3-2 exhibits excellent gas selectivity and long-term stability. The improved sensing performance of ZnSnO3-2 was attributed to its large specific surface area and abundant oxygen vacancies. Additionally, the gas sensing mechanism for enhancing n-butanol detection was comprehensively analyzed. These results highlight the potential of nanoflower-like ZnSnO3 as a promising candidate for n-butanol gas sensing material, offering both high sensitivity and selectivity. Moreover, this research provides valuable guidance for the development and optimization of gas sensing materials for applications in environmental monitoring and industrial safety. © 2024, The Authors. All rights reserved.

关键词： Perovskite

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AO-DETR: Anti-Overlapping DETR for X-Ray Prohibited Items Detection

arXiv

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arXiv 2024年

作者： Li, Mingyuan Jia, Tong Wang, Hao Ma, Bowen Lin, Shuyang Cai, Da Chen, Dongyue College of Information Science and Engineering Northeastern University Liaoning Shenyang110819 China Foshan Graduate School of Innovation Northeastern University Guangdong Foshan528311 China Key Laboratory of Data Analytics and Optimization for Smart Industry Ministry of Education Northeastern University Liaoning Shenyang110819 China

Prohibited item detection in X-ray images is one of the most essential and highly effective methods widely employed in various security inspection scenarios. Considering the significant overlapping phenomenon in X-ray prohibited item images, we propose an Anti-Overlapping DETR (AO-DETR) based on one of the state-of-the-art general object detectors, DINO. Specifically, to address the feature coupling issue caused by overlapping phenomena, we introduce the Category-Specific One-to-One Assignment (CSA) strategy to constrain category-specific object queries in predicting prohibited items of fixed categories, which can enhance their ability to extract features specific to prohibited items of a particular category from the overlapping foreground-background features. To address the edge blurring problem caused by overlapping phenomena, we propose the Look Forward Densely (LFD) scheme, which improves the localization accuracy of reference boxes in mid-to-high-level decoder layers and enhances the ability to locate blurry edges of the final layer. Similar to DINO, our AO-DETR provides two different versions with distinct backbones, tailored to meet diverse application requirements. Extensive experiments on the PIXray and OPIXray datasets demonstrate that the proposed method surpasses the state-of-the-art object detectors, indicating its potential applications in the field of prohibited item detection. The source code will be released at https://***/Limingyuan001/AO-DETR. Copyright © 2024, The Authors. All rights reserved.

关键词： Object detection

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Open-Vocabulary X-ray Prohibited Item Detection via Fine-tuning CLIP

arXiv

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arXiv 2024年

作者： Lin, Shuyang Jia, Tong Wang, Hao Ma, Bowen Li, Mingyuan Chen, Dongyue The College of Information Science and Engineering Northeastern University Liaoning Shenyang110819 China The Key Laboratory of Data Analytics and Optimization for Smart Industry Ministry of Education Northeastern University Liaoning Shenyang110819 China The Foshan Graduate School of Innovation Northeastern University Guangdong Foshan528311 China

X-ray prohibited item detection is an essential component of security check and categories of prohibited item are continuously increasing in accordance with the latest laws. Previous works all focus on close-set scenarios, which can only recognize known categories used for training and often require time-consuming as well as labor-intensive annotations when learning novel categories, resulting in limited real-world applications. Although the success of vision-language models (e.g. CLIP) provides a new perspectives for open-set X-ray prohibited item detection, directly applying CLIP to X-ray domain leads to a sharp performance drop due to domain shift between X-ray data and general data used for pre-training CLIP. To address aforementioned challenges, in this paper, we introduce distillation-based open-vocabulary object detection (OVOD) task into X-ray security inspection domain by extending CLIP to learn visual representations in our specific X-ray domain, aiming to detect novel prohibited item categories beyond base categories on which the detector is trained. Specifically, we propose X-ray feature adapter and apply it to CLIP within OVOD framework to develop OVXD model. X-ray feature adapter containing three adapter submodules of bottleneck architecture, which is simple but can efficiently integrate new knowledge of X-ray domain with original knowledge, further bridge domain gap and promote alignment between X-ray images and textual concepts. Extensive experiments conducted on PIXray and PIDray datasets demonstrate that proposed method performs favorably against other baseline OVOD methods in detecting novel categories in X-ray scenario. It outperforms previous best result by 15.2 AP50 and 1.5 AP50 on PIXray and PIDray with achieving 21.0 AP50 and 27.8 AP50 respectively. Furthermore, our model can be directly transferred to different X-ray datasets without fine-tuning, verifying its generalization ability. Copyright © 2024, The Authors. All rights reserved.

关键词： Object detection

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Hollow Urchin Co-Fe2o3 With Outstanding Selectivity and Fast Responding For Ppb Level Nh3 Sensing Via Lewis Acid-Base Effect

SSRN

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SSRN 2023年

作者： Liu, Yang Ji, Hanyang Yuan, Zhenyu Zhu, Hongmin Kong, Lu Gao, Hongliang Meng, Fanli College of Information Science and Engineering Northeastern University Shenyang110819 China Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology Qinhuangdao066004 China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Shenyang110819 China Key Laboratory of Data Analytics and Optimization for Smart Industry Northeastern University Ministry of Education Shenyang110819 China

Layered double hydroxides (LDH) are a class of layered compounds, which are popular among researchers because of the large specific surface area and excellent catalytic properties. In this work, Co-Fe2O3 2 was prepared with urchin Co-Fe LDH as a precursor. The morphology of Co-Fe2O3 2 was not changed, and burrs were evenly distributed on the surface with a diameter of about 3-5 nm. Co-Fe2O3 2 showed outstanding gas sensitivity to NH3, with favourable repeatability, stability and selectivity, as well as an ultra-low application detection limit of 10 ppb (response was 5%). The response of the sensor to 10 ppm NH3 at 275 °C was 298% with a fast response/recovery rate (7.2/5.4 s). BET revealed that the specific surface area of Co-Fe2O3 2 was 114.5 m2/g, which could provide more sites for gas adsorption and reaction. The results of XPS, Raman, and FTIR spectras indicated that some Co2+ replaced the position of Fe3+ to generate abundant oxygen vacancy, which could enhance the activity of the sensitive material. The small size effect and the formation of p-n junction increased the adsorption capacity of the sensitive material. Moreover, the synergistic effect of Lewis acid-base and catalytic of Co3O4 greatly improved the selectivity of the sensor to NH3. The growth process and principle of Co-Fe LDH were discussed and analyzed in detail, which provided a new idea for the controlled synthesis of LDH. Co-Fe2O3 2 is a promising gas-sensitive material for the rapid detection of ammonia. © 2023, The Authors. All rights reserved.

关键词： Oxygen vacancies

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Highly Sensitive Acetic Anhydride Sensor Based on Cd-Doped Biphase In2o3 Microspheres

SSRN

引用

SSRN 2023年

作者： Meng, Fanli Zhang, Hua Guo, Yinghao Zhang, Haoting College of Information Science and Engineering Northeastern University Shenyang110819 China Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology Qinhuangdao066004 China 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

New drugs emerge in an endless stream, the global drug supply is increasing, and the number of drug users is steadily rising, so the detection of acetic anhydride-a raw material for drug preparation is of great significance for controlling the spread of drugs. The crystal phase of semiconductor metal oxides has an important impact on oxygen vacancy, microscopic morphology, specific surface area, and high-energy surface exposure, which in turn affects the catalytic and gas-sensing effects of materials. Ions doped can sometimes achieve the purpose of changing the crystal phase. In this paper, Cd-doped biphase (cubic phase and hexagonal phase) In2O3 nanospheres sensitive to acetic anhydride were synthesized via one easy hydrothermal process. The fabricated sensor has high sensitivity (372) to 100 ppm acetic anhydride in the dry environment of 220 °C, excellent selectivity and good stability. X-ray diffraction (XRD), energy dispersive spectroscopy (EDS) analysis, and scanning electron microscopy (SEM) were used to observe the crystal phase, elemental information and nanoscale appearance of the prepared compounds, and the gas-sensitive mechanism was briefly analyzed according to the characterization information. The enhancing acetic anhydride sensing properties are owing to the change of internal electronic channels and the crystal structure of In2O3 material caused by Cd-doped. © 2023, The Authors. All rights reserved.

关键词： Scanning electron microscopy

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Prospects for probing the interaction between dark energy and dark matter using gravitational-wave dark sirens with neutron star tidal deformation

arXiv

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arXiv 2023年

作者： Li, Tian-Nuo Jin, Shang-Jie Li, Hai-Li Zhang, Jing-Fei Zhang, Xin College of Sciences Northeastern University Shenyang110819 China Basic Teaching Department Shenyang Institude of Engineering Shenyang110136 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

Gravitational wave (GW) standard siren observations provide a rather useful tool to explore the evolution of the universe. In this work, we wish to investigate whether the dark sirens with neutron star (NS) deformation from third-generation (3G) GW detectors could help probe the interaction between dark energy and dark matter. We simulate the GW dark sirens of four detection strategies based on the three-year observation and consider four phenomenological interacting dark energy models to perform cosmological analysis. We find that GW dark sirens could provide tight constraints on Ωm and H0 in the four IDE models, but perform not well in constraining the dimensionless coupling parameter β with the interaction proportional to the energy density of cold dark matter. Nevertheless, the parameter degeneracy orientations of CMB and GW are almost orthogonal, and thus the combination of them could effectively break cosmological parameter degeneracies, with the constraint errors of β being 0.00068-0.018. In addition, we choose three typical equation of states (EoSs) of NS, i.e., SLy, MPA1, and MS1, to investigate the effect of NS’s EoS in cosmological analysis. The stiffer EoS could give tighter constraints than the softer EoS. Nonetheless, the combination of CMB and GW dark sirens (using different EoSs of NS) shows basically the same constraint results of cosmological parameters. We conclude that the dark sirens from 3G GW detectors would play a crucial role in helping probe the interaction between dark energy and dark matter, and the CMB+GW results are basically not affected by the EoS of NS. Copyright © 2023, The Authors. All rights reserved.

关键词： Sirens

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Probing a polymerized black hole with the frequency shifts of photons

arXiv

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arXiv 2022年

作者： Fu, Qi-Ming Zhang, Xin College of Sciences Northeastern University Shenyang110819 China Institute of Physics Shaanxi University of Technology Hanzhong723000 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

As is well-known, black hole plays an important role in probing the quantum effects of gravity in the strong-field regime. In this paper, we focus on a polymerized black hole and investigate the quantum effects on the redshift, blueshift and gravitational redshift of photons emitted by massive particles revolving around this black hole. With a general relativistic formalism, we obtain two elegant and concise expressions for the mass of the black hole and the quantum parameter in terms of few direct observables, and find that all the frequency shifts of photons decrease with the quantum parameter. By expanding the total frequency shift for large orbit of the emitter, low peculiar redshift, and small azimuthal angle, we find that the leading contributions to the frequency shift are originated from the kinematic shift and peculiar shift, and the quantum effects make a negligible contribution. In addition, we study the effects of the plasma on the redshift/blueshift for the first time, and conclude that the presence of plasma results in the decrease of the redshift/blueshift. Copyright © 2022, The Authors. All rights reserved.

关键词： Black holes

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