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Global sensitivity analysis of wheat grain yield and quality and the related process variables from the DSSAT-CERES model based on the extended Fourier Amplitude Sensitivity Test method

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Journal of Integrative Agriculture 2019年第7期18卷 1547-1561页

作者： LI Zhen-hai JIN Xiu-liang LIU Hai-long XU Xin-gang WANG Ji-hua Key Laboratory of Agri-lnformatics Ministry of Agriculture and Rural AffairsBeijing 100097P.R. China Beijing Research Center for Information Technology in Agriculture Beijing Academy of Agriculture and Forestry SciencesBeijing 100097P R.China UMR EMMAH INRANAPVAvignon 84914France Agricultural Information Institute Chinese Academy of Agricultural Sciences/Key Laboratory of Agri-lnformation Service TechnologyMinistry of Agriculture and Rural AffairsBeijing 100081P.R. China Beijing Research Center for Agri-Food Testing and Farmland Monitoring Beijing Academy of Agriculture and Forestry SciencesBeijing 100097P.R.China

A crop growth model,integrating genotype,environment,and management factor,was developed to serve as an analytical tool to study the influence of these factors on crop growth,production,and agricultural planning.A major challenge of model application is the optimization and calibration of a considerable number of *** analysis(SA) has become an effective method to identify the importance of various *** this study,the extended Fourier Amplitude Sensitivity Test(EFAST) approach was used to evaluate the sensitivity of the DSSAT-CERES model output responses of interest to 39 crop genotype parameters and six soil *** outputs for the SA included grain yield and quality(take grain protein content(GPC) as an indicator) at maturity stage,as well as leaf area index,aboveground biomass,and aboveground nitrogen accumulation at the critical process *** key results showed that:(1) the influence of parameter bounds on the sensitivity results was slight and less than the impacts from the significance of the parameters themselves;(2) the sensitivity parameters of grain yield and GPC were different,and the sensitivity of the interactions between parameters to GPC was greater than those between the parameters to grain yield;and(3) the sensitivity analyses of some process variables,including leaf area index,aboveground biomass,and aboveground nitrogen accumulation,should be performed ***,some parameters,which improve the model’s structure and the accuracy of the process simulation,should not be ignored when maturity output as an objective variable is studied.

关键词： global sensitivity analysis DSSAT EFAST wheat yield grain protein content

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21-cm foreground removal using AI and the frequency-difference technique

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Physical Review D 2024年第6期109卷 063509-063509页

作者： Feng Shi Haoxiang Chang Le Zhang Huanyuan Shan Jiajun Zhang Suiping Zhou Ming Jiang Zitong Wang School of Aerospace Science and Technology Xidian University Xi’an 710126 People’s Republic of China Peng Cheng Laboratory No. 2 Xingke 1st Street Shenzhen 518000 People’s Republic of China School of Physics and Astronomy Sun Yat-sen University 2 Daxue Road Tangjia Zhuhai 519082 People’s Republic of China CSST Science Center for the Guangdong-Hong Kong-Macau Greater Bay Area Zhuhai 519082 People’s Republic of China Shanghai Astronomical Observatory (SHAO) Nandan Road 80 Shanghai 200030 China University of Chinese Academy of Sciences Beijing 100049 People’s Republic of China National Key Laboratory of Radar Signal Processing Xidian University Xi’an 710126 People’s Republic of China

The deep learning technique has been employed in removing foreground contaminants from 21-cm intensity mapping, but its effectiveness is limited by the large dynamic range of the foreground amplitude. In this study, we develop a novel foreground removal technique grounded in U-Net networks. The essence of this technique lies in introducing an innovative data preprocessing step specifically, utilizing the temperature difference between neighboring frequency bands as input. Combining with the frequency difference, we refer to our method as the UNet-fd (UNet frequency-difference), where the U-Net structure is the same as that in deep21. Based on our tests, we demonstrate that this frequency-difference preprocessing technique can substantially reduce the dynamic range of foreground amplitudes by approximately two orders of magnitude. This reduction proves to be highly advantageous for the U-Net foreground removal. We observe that the HI signal can be reliably recovered, as indicated by the cross-correlation power spectra showing unity agreement at the scale of k≲0.3 hMpc−1 in the absence of instrumental effects. Moreover, accounting for the systematic beam effects, our reconstruction displays consistent autocorrelation and cross-correlation power spectrum ratios at the 1σ level across scales k≲0.1 hMpc−1, with only a 10% reduction observed in the cross-correlation power spectrum at k≃0.2 hMpc−1. The effects of redshift-space distortion are also reconstructed successfully, as evidenced by the quadrupole power spectra matching with the target truth. In order to test how thermal noise affects the performance of our method, we simulated various white noise levels in the map. This shows the mean cross-correlation ratio R¯cross≳0.8 when the level of the thermal noise is smaller than or equal to that of the HI signal. In comparison, our method outperforms the traditional principal component analysis (PCA) method. The PCA-derived cross-correlation ratios are underestimated b

关键词： Large scale structure of the Universe

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Contribution of Atmospheric Deposition to Halogenated Polycyclic Aromatic Hydrocarbons in Surface Sediments: A Validation Study

SSRN

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SSRN 2021年

作者： Du, Yanjun Xu, Xiong Liu, Quanzhen Lin, Lihua Bai, Lu Wang, Donghong Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing100085 China University of Chinese Academy of Sciences Beijing100049 China National Institute of Environmental Health Chinese Center for Disease Control and Prevention Bejing100021 China

Surface sediments are both sinks and sources of chlorinated and brominated polycyclic aromatic hydrocarbons (Cl/Br-PAHs) in the environment. It is important to study the source of Cl/Br-PAHs in the surface sediment for controlling the ecological risk of Cl/Br-PAHs. Clues from the previous research suggested that atmospheric sedimentation may be one of the main sources of Cl/Br-PAHs in sediment. However, due to the lack of matched sediment and atmospheric Cl/Br-PAHs data, the contribution of atmospheric deposition to Cl/Br-PAHs in sediment has not been confirmed. This study investigated the characteristics of 37 Cl/Br-PAHs and validated the contribution of atmospheric sedimentation to Cl/Br-PAHs in sediment by a case study in the surface sediments of the Chaobai River, China. To the best of our knowledge, four Cl-PAHs and eleven Br-PAHs were found in the sediments for the first time. The total concentrations of 18 Cl-PAH species were 76–2301 pg/g, while those of Br-PAHs were 6–238 pg/g. The toxic equivalent quantities (TEQ) of the Cl-PAHs in surface sediments in the water conservation area and in the urban comparison area were 0.73 pg TEQ/g and 2.21 pg TEQ/g, respectively. The TEQ of the Br-PAHs in surface sediments in the water conservation area and in the urban comparison area were 2.85×10 -2 pg TEQ/g and 6.6×10 -2 pg TEQ/g, respectively. Based on the characteristics comparison and correlation analysis of Cl/Br-PAHs in both sediment and ambient air, it was initially confirmed the contribution of atmospheric deposition to Cl-PAHs in sediments. However, there was no conclusion of Br-PAHs in sediment similar to Cl-PAHs in sediment. It was inferred that the sources of Br-PAHs in sediment were different from Cl-PAHs in sediment. © 2021, The Authors. All rights reserved.

关键词： Polycyclic aromatic hydrocarbons

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Fault Diagnosis technology of Rolling Bearing in Space Station

Fault Diagnosis Technology of Rolling Bearing in Space Stati...

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2019 International Conference on Artificial Intelligence Technologies and Applications, ICAITA 2019

作者： Dequan, Yu Wenbo, Wu Hongyong, Fu Yang, Wang Ke, Wang Technology and Engineering Center for Space Utilization Key Laboratory of Space Utilization Chinese Academy of Science Beijing China

With the development of space station engineering, rolling bearings have been widely used in space station. Whether the bearing is healthy or not is related to the safety of the experimental facilities. Fault diagnosis of rolling bearings includes time domain analysis and frequency domain analysis. By analyzing bearing fault information, time-frequency information entropy is more representative as fault feature. Firstly, the vibration signal of acceleration sensor is decomposed by EEMD method, and the intrinsic mode function is obtained. The time-frequency information is obtained by Fourier transform, and the information entropy of the time-frequency information is calculated. Then, the fault feature is self-adaptive dimensionality reduction. Finally, the fault feature is trained by using support vector machine, and the data is tested. The experimental results show that the method can diagnose bearing fault with high accuracy. © 2019 IOP Publishing Ltd. All rights reserved.

关键词： Space stations

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Prophage induction and quorum sensing enhance biofilm stability and resistance under ammonia-oxidizing bacteria-mediated oxidative stress

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Water research 2025年 284卷 124010页

作者： Xiurong Ju Huifang Sun Chujin Ruan Haibo Wang Baoyou Shi Pedro J J Alvarez Pingfeng Yu Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Institute of Resources and Environmental Engineering Shanxi University Taiyuan 030006 Shanxi China. Department of Environmental Microbiology Swiss Federal Institute of Aquatic Science and Technology (Eawag) Dübendorf 8600 Switzerland. Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China. Electronic address: hbwang@***. Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China. Department of Civil and Environmental Engineering and Rice WaTER Institute Rice University Houston TX 77005 USA. College of Environmental and Resource Sciences Zhejiang University Hangzhou 310058 China. Electronic address: yupf@***.

Ammonia-oxidizing bacteria (AOB) and prophage-carrying bacteria are prevalent in water treatment and reuse systems, yet their interactions and implications for biofilm formation and microbial risks remain insufficiently understood. Here, we demonstrate that oxidative stress arising from the metabolism of the AOB Nitrosomonas europaea induces prophage activation in lysogenized Escherichia coli (λ+). This activation triggers cellular lysis, leading to the release of intracellular components (e.g., protein and DNA) and upregulated quorum sensing (QS) followed by biosynthesis and excretion of extracellular polymeric substance (EPS). Integrated transcriptomic and proteomic analysis revealed that the presence of N. europaea significantly upregulated QS- and EPS-related genes by 2.14-2.93 and 2.81-3.11 folds in E. coli (λ+), respectively. Surviving E. coli (λ+) exhibited enhanced prophage-bacterium symbiosis and activated toxin-antitoxin systems, enhancing their resilience to environmental stress. These microbial adaptations markedly increased EPS production, fostering biofilm development and conferring enhanced biofilm resilience to disinfectants and bacterial antibiotic tolerance. Furthermore, metagenomic analysis at the microbial community wide level demonstrated that ammonia addition-driven AOB enrichment stimulated multi-species biofilm formation, promoted bacterium-phage interactions, and increased bacterial antibiotic resistance. Overall, our findings reveal that oxidative stress driven by AOB accelerates biofilm development, an overlooked phenomenon with potential to exacerbate microbial risks.

关键词： Ammonia-oxidizing bacteria Biofilm Lysogenic phages Microbial risks Oxidative stress

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Low-temperature resistivity anomaly and weak spin disorder in Co2MnGa epitaxial thin films

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Physical Review B 2020年第18期101卷 184434-184434页

作者： Shucheng Tong Xupeng Zhao Dahai Wei Jianhua Zhao State Key Laboratory of Superlattices and Microstructures Institute of Semiconductors Chinese Academy of Sciences P.O. Box 912 Beijing 100083 China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of Sciences Beijing 100049 China Beijing Academy of Quantum Information Science Beijing 100193 China

The topological material of Co2MnGa with potentially high spin polarization has attracted more and more attention, in the fields of fundamental science and spintronic applications. Here we report the electrical- and magnetotransport behaviors in epitaxial Co2MnGa thin films. An angle-independent negative linear magnetoresistance and a negative anisotropy magnetoresistance are observed in the whole temperature range from 3 to 300 K, indicating the existence of weak spin disorder and a high spin polarization. Intriguingly, with decreasing temperature an anomalous resistivity upturn that exhibits −T1/2 dependence is observed, and this phenomenon is robust under magnetic fields. Further analysis demonstrates that the three-dimensional enhanced electron-electron interaction effect is responsible for these phenomena rather than the orbital two-channel Kondo effect or other quantum interference effects, which provides deeper insight into the transport behavior of the Co2MnGa materials.

关键词： Magnetotransport Topological materials Transport phenomena

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Broadband Terahertz Quantum Cascade Laser Dual-Comb Sources under Off-Resonant Microwave Injection

arXiv

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arXiv 2021年

作者： Liao, Xiaoyu Li, Ziping Zhou, Kang Guan, Wen Zhao, Yiran Wang, Chenjie Wan, Wenjian Yang, Sijia Zhang, Zhenzhen Wang, Chang Cao, J.C. Zeng, Heping Li, Hua Key Laboratory of Terahertz Solid State Technology Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai200050 China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences Beijing100049 China School of Information Science and Technology ShanghaiTech University 393 Middle Huaxia Road Shanghai201210 China State Key Laboratory of Precision Spectroscopy East China Normal University Shanghai200062 China Chongqing Key Laboratory of Precision Optics Chongqing Institute of East China Normal University Chongqing401120 China

Broadband dual-comb spectroscopy has attracted increasing interests due to its unique advantages in high spectral resolution, fast detection, and so on. Although the dual-comb technique is relatively mature in the infrared wavelengths, it is, currently, not commercially capable of practical applications in the terahertz regime due to the lack of high performance broadband terahertz dual-comb sources. In the terahertz frequency range, the electrically pumped quantum cascade laser (QCL) is a suitable candidate for the dual-comb operation. However, free running terahertz QCL dual-comb sources normally show limited optical bandwidths (∼100-200 GHz). Although the resonant microwave injection locking has been widely used to broaden the emission spectra of terahertz QCLs by modulating the laser drive current at the cavity round-trip frequency, it is hard to be employed to broaden the dual-comb bandwidths due to the large phase noise induced by the resonant injection and non-ideal microwave circuits. Therefore, it is challenging to obtain broadband terahertz dual-comb sources that can fully exploits the laser gain bandwidth. Here, we employ an off-resonant microwave injection to significantly broaden the dual-comb bandwidth of a terahertz QCL dual-comb source emitting around 4.2 THz. The measured optical dual-comb bandwidth is broadened from 147 GHz in free running to >450 GHz under the off-resonant injection. The broadened dual-comb bandwidth is experimentally proved by the transmission measurements of a filter and a GaAs etalon. By performing a simple numerical analysis based on a rate equation model, we explain that the broadband dual-comb operation under the off-resonant microwave injection could be resulted from a wider lasing bandwidth and a higher degree of phase matching. © 2021, CC BY.

关键词： Bandwidth

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Runoff Simulation and analysis of Water Source in the High-Elevation and Cold Area of the Shaliu River Basin

SSRN

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SSRN 2024年

作者： Wang, Yunying Li, Zongxing Li, Guohui Si, Lanping Zhang, BaiJuan Li, Zongjie Observation and Research Station of Eco-Hydrology and National Park by Stable Isotope Tracing in Alpine region Gansu Qilian Mountains Ecology Research Center Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Lanzhou730000 China University of Chinese Academy of Sciences Beijing100049 China College of Geography and Environmental Science Northwest Normal University Lanzhou730070 China College of Earth and Environmental Sciences Lanzhou University Lanzhou730000 China College of Energy and Power Engineering Lanzhou University of Technology Lanzhou730050 China

This study selects the Shaliu River Basin, a small-scale watershed in a cold area, as the research subject, with the research time scale spanning from 1960 to 2022. The study employs the SWAT model as the hydrological base model and subsequently improves the snow and soil freeze-thaw modules. The research results show that: 1) On an annual scale, during the calibration period from 1965 to 2000 and the validation period from 2001 to 2022, The improved model has seen a certain degree of enhancement in the simulation, The improved model's NSE, KGE, and R2 are 0.80, 0.85, and 0.80, respectively, showing good simulation effects;2) According to the source of runoff input,the results show that in the improved model, precipitation, snowmelt, and groundwater contribute to the runoff by 53.81%, 8.63%, and 37.56%, respectively. 3) On a spatiotemporal scale, blue water showed a significant increasing trend, while green water showed a slight decreasing trend, and the green water coefficient showed a significant decreasing trend, with the highest values in August. The content of blue water and the green water coefficient showed a pattern of being low in the middle and high at both ends;the variation in precipitation showed a pattern of being higher upstream and lower downstream. Green water resources were found to be much higher than blue water resources at the basin scale. © 2024, The Authors. All rights reserved.

关键词： SWAT

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CONVERGENCE analysis FOR MINIMUM ACTION METHODS COUPLED WITH A FINITE DIFFERENCE METHOD

arXiv

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arXiv 2021年

作者： Hong, Jialin Jin, Diancong Sheng, Derui Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing100190 China School of Mathematical Sciences University of Chinese Academy of Sciences Beijing100049 China School of Mathematics and Statistics Huazhong University of Science and Technology Wuhan430074 China Hubei Key Laboratory of Engineering Modeling and Scientific Computing Huazhong University of Science and Technology Wuhan430074 China Department of Applied Mathematics The Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong

The minimum action method (MAM) is an effective approach to numerically solving minimums and minimizers of Freidlin–Wentzell (F-W) action functionals, which is used to study the most probable transition path and probability of the occurrence of transitions for stochastic differential equations (SDEs) with small noise. In this paper, we focus on MAMs based on a finite difference method, and present the convergence analysis of minimums and minimizers of the discrete F-W action functional. The main result shows that the convergence orders of the minimum of the discrete F-W action functional in the cases of multiplicative noises and additive noises are 1/2 and 1, respectively. Our main result also reveals the convergence of the stochastic θ-method for SDEs with small noise in terms of large deviations. Copyright © 2021, The Authors. All rights reserved.

关键词： Finite difference method

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Design and on-orbit status of the trigger system for the DAMPE mission

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Research in Astronomy and Astrophysics 2019年第9期19卷 13-20页

作者： Yong-Qiang Zhang Jian-Hua Guo Yang Liu Chang-Qing Feng Yun-Long Zhang Tie-Kuang Dong Jing-Jing Zang Chuan Yue Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing210008China University of Chinese Academy of Sciences Beijing100049China State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei230026China

DArk Matter Particle Explorer(DAMPE), the first Chinese astronomical satellite, was successfully launched at the Jiuquan Satellite Launch Center on 2015 Dec. 17. DAMPE consists of four subdetectors: Plastic Scintillator array Detector(PSD), Silicon-Tungsten tracKer-converter(STK), Bismuth Germanium Oxide(BGO) imaging calorimeter and NeUtron Detector(NUD). The global hardware trigger signal, which is generated by hits from the BGO calorimeter and the trigger logic board in the data acquisition system(DAQ), is responsible for event selection and DAQ synchronization of DAMPE. On orbit,to improve the detection efficiency, different trigger logics are used for event selection in different regions of latitude. The DAMPE trigger system compresses the average on-orbit trigger rate to 60 Hz and reduces science data mass to less than 13 GB per day to meet the requirement for the satellite’s data link. The whole trigger system has run stably up to now, ensuring excellent on-orbit operation of DAMPE.

关键词： Dark Matter instrumentation:detectors methods:data analysis

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