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China Geology 2024年第2期7卷 365-368,I0004-I0007页

作者： Kai Weng ji-fei cao Divayev-Farid Karibovich Jahongir-Jurabekovich Movlanov Bo Chen Zhong-ping Ma Xi’an Center of Geological Survey China Geological SurveyXi’an 710119China The Center for Geoinnovation Technologies Doctor of Sciences in Geology and Mineralogy University of Geological ScienceTashkent 100060Uzbekistan

*** The Central Asian Orogenic Belt(caoB),which is located between the European craton,Siberian craton,and Tarim-North China craton(Fig.1a),is the largest phanerozoic accretionary orogen in the *** resulted from the longterm subduction and accretion of the Paleo-Asian Ocean(PAO).The PAO has been in existence since at least the late Mesoproterozoic(about 1020 Ma).However,there has been debate about the closing time of the PAO.

关键词： Asian Paleo Tianshan

Optimizing the key parameter to accelerate the recovery of AMOC under a rapid increase of greenhouse gas forcing

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 39-45页

作者： Haolan Ren fei Zheng Tingwei cao Qiang Wang International Center for Climate and Environment Science(ICCES) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina College of Oceanography Hohai UniversityNanjingChina CAS Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of Sciences and Pilot National Laboratory for Marine Science and Technology(Qingdao)QingdaoChina

Atlantic Meridional Overturning Circulation(AMOC)plays a central role in long-term climate variations through its heat and freshwater transports,which can collapse under a rapid increase of greenhouse gas forcing in climate *** studies have suggested that the deviation of model parameters is one of the major factors in inducing inaccurate AMOC *** this work,with a low-resolution earth system model,the authors try to explore whether a reasonable adjustment of the key model parameter can help to re-establish the AMOC after its *** a new optimization strategy,the extra freshwater flux(FWF)parameter is determined to be the dominant one affecting the AMOC’s *** traditional ensemble optimal interpolation(EnOI)data assimilation and new machine learning methods are adopted to optimize the FWF parameter in an abrupt 4×CO_(2) forcing experiment to improve the adaptability of model parameters and accelerate the recovery of *** results show that,under an abrupt 4×CO_(2) forcing in millennial simulations,the AMOC will first collapse and then re-establish by the default FWF parameter ***,during the parameter adjustment process,the saltier and colder sea water over the North Atlantic region are the dominant factors in usefully improving the adaptability of the FWF parameter and accelerating the recovery of AMOC,according to their physical relationship with FWF on the interdecadal timescale.

关键词： Recovery of AMOC 4×CO_(2) forcing Key parameter Parameter estimation Data assimilation Machine learning

Positive effect of Mo on mechanical properties of a Ni-42W-10Co-x Mo medium heavy alloy

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China Foundry 2025年

作者： Guo-xin cao jian-xin Dong Yong-sheng He He jiang Fang Hao Zhi-hua Nie Teng-fei Ma Bao-quan Fu School of Materials Science and Engineering University of Science and Technology Beijing Xi'an Superalloy Technology Co. Ltd. School of Materials Science and Engineering Beijing Institute of Technology Key Laboratory of Air-driven Equipment Technology of Zhejiang Province Quzhou University

In this study,a novel Ni-W-Co-Mo medium heavy alloy (MHA) was designed to improve its mechanical strength via Mo *** the Ni-42W-10Co-xM o alloy series,where x represents the weight percent of Mo and varies between 0,1,2,5,and 10,the microstructure transitions from a dendritic structure to a hypoeutectic structure as the Mo content increases from 0 to 5wt.%.Moreover,as the Mo content increases from 0to 10wt.%,the distribution of theμ-phase shifts from being individually dispersed to forming aggregates,and its volume fraction rises from 0.5%to 7.9%.Notably,theμ-phase evolves into an eutectic microstructure,which helps in minimizing the segregation of *** change is accompanied by a substantial enhancement in mechanical properties;specifically,the compressive yield strength at room temperature increases from 350 MPa to 646 MPa,indicating a significant 85%***,the microhardness increases from 230 HV to 304 *** dynamics simulations further reveal that the strengthening mechanism of Ni-42W-10Co-xM o alloys is Mo-induced solid solution strengthening and precipitation strengthening.

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Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第1期68卷 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming cao Yao-Wen Chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang Zhi-Li Zuo Han Guo Zi-fei Xu Ying Zeng Yun-Dong Wu Xiao-jiang Hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids

接触网隧道吊柱智能化安装装备研制及工程实践应用

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科学技术创新 2025年第1期 44-47页

作者：曹斐中国铁建电气化局集团第二工程有限公司山西太原

国内高速铁路的飞速发展,带动地方经济发展的同时也有效地促进了铁路建造技术质的飞跃。同时,随着智能建造理念的提出,有效地推动了建设行业智能装备、智能设备的投入应用。但当前高速铁路接触网工程在现场施工环节依然存在诸多施工效... 详细信息

国内高速铁路的飞速发展,带动地方经济发展的同时也有效地促进了铁路建造技术质的飞跃。同时,随着智能建造理念的提出,有效地推动了建设行业智能装备、智能设备的投入应用。但当前高速铁路接触网工程在现场施工环节依然存在诸多施工效率低下、安全风险高等一些列问题,特别是现阶段高速铁路隧道断面越来越大,隧道内接触网吊柱安装高空作业风险隐患尤为关键。本文面向建设施工一线建设,通过对隧道内接触网吊柱智能化安装相关技术进行深入研究,完成适用于高速铁路隧道内接触网吊柱安装机械化、自动化安装装备的制造及工程实践应用。研究该装备的目标是开发基于视觉引导的高精度自动对位安装装备,完成大断面隧道内接触网吊柱安装的需要。

关键词：双线隧道接触网吊柱机械化自动化自动对位

Spatio-Temporal Wind Speed Prediction Based on Variational Mode Decomposition

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Computer Systems Science & Engineering 2022年第11期43卷 719-735页

作者： Yingnan Zhao Guanlan ji fei Chen Peiyuan ji Yi cao School of Computer and Science Nanjing University of Information Science and TechnologyNanjing210044China Department of Electrical and Computer Engineering University of WindsorWindsorN9B 3P4Canada

Improving short-term wind speed prediction accuracy and stability remains a challenge for wind forecasting *** paper proposes a new variational mode decomposition(VMD)-attention-based spatio-temporal network(VASTN)method that takes advantage of both temporal and spatial correlations of wind ***,VASTN is a hybrid wind speed prediction model that combines VMD,squeeze-and-excitation network(SENet),and attention mechanism(AM)-based bidirectional long short-term memory(BiLSTM).VASTN initially employs VMD to decompose the wind speed matrix into a series of intrinsic mode functions(IMF).Then,to extract the spatial features at the bottom of the model,each IMF employs an improved convolutional neural network algorithm based on channel AM,also known as ***,it combines BiLSTM and AM at the top layer to extract aggregated spatial features and capture temporal ***,VASTN accumulates the predictions of each IMF to obtain the predicted wind *** method employs VMD to reduce the randomness and instability of the original data before employing AM to improve prediction accuracy through mapping weight and parameter *** results on real-world data demonstrate VASTN’s superiority over previous related algorithms.

关键词： Short-term wind speed prediction variational mode decomposition attention mechanism SENet BiLSTM

Fire Detection Method Based on Depthwise Separable Convolution and YOLOv3

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International Journal of Automation and computing 2021年第2期18卷 300-310页

作者： Yue-Yan Qin jiang-Tao cao Xiao-fei ji School of Information and Control Engineering Liaoning Shihua UniversityFushun 113001China School of Automation Shenyang Aerospace UniversityShenyang 110136China

Recently,video-based fire detection technology has become an important research topic in the field of machine *** paper proposes a method of combining the classification model and target detection model in deep learning for fire ***,the depthwise separable convolution is used to classify fire images,which saves a lot of detection time under the premise of ensuring detection ***,You Only Look Once version 3(YOLOv3)target regression function is used to output the fire position information for the images whose classification result is fire,which avoids the problem that the accuracy of detection cannot be guaranteed by using YOLOv3 for target classification and position *** the same time,the detection time of target regression for images without fire is greatly reduced *** experiments were tested using a network public *** detection accuracy reached 98%and the detection rate reached *** method not only saves the workload of manually extracting flame characteristics,reduces the calculation cost,and reduces the amount of parameters,but also improves the detection accuracy and detection rate.

关键词： Fire detection depthwise separable convolution fire classification You Only Look Once version 3(YOLOv3) target regression

Application of New Empirical Models Based on Mathematical Statistics in the Through-Flow Analysis

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Journal of Thermal Science 2021年第6期30卷 2087-2098页

作者： fei Teng ji Lucheng School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

The through-flow analysis is an important part in the compressor design *** this part,lots of empirical models are used to predict the compressor aerodynamic *** models are all based on the early experimental results of low-load and low-speed compressors;so,they may not be suitable for modern compressor performance *** this study,several empirical models were reviewed,and two new models to estimate the minimum blade profile loss and minimum-loss deviation angle were established using mathematical ***,the original models with poor accuracy were replaced by these two models in through-flow ***,three compressors(Rotor 67,Stage 35,and a 4-stage repeating stage)were simulated using both the original and new *** final results show that the new models have better accuracy in estimating the performance parameters than the original *** indicates that it is feasible to use mathematical statistical methods to establish the empirical models,and this method provides an idea for the improvement of other empirical models in through-flow program.

关键词： through-flow analysis empirical models blade loss deviation regression analysis

考虑场地效应的多点地震动作用下边坡永久位移分析

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岩土工程学报 2025年第1期47卷 65-75页

作者：宋健潘驭航陆朱汐姬建张飞高玉峰河海大学岩土力学与堤坝工程教育部重点实验室江苏南京210024 河海大学土木与交通学院江苏南京210024

地震动引起的边坡土层非线性动力响应可能导致坡体不同位置的地震动加速度时程不一致,从而对整个滑动体的极限平衡状态及之后的地震累积永久位移产生影响。为了研究场地效应对边坡地震永久位移的影响,基于极限平衡条分法,通过对不同土... 详细信息

地震动引起的边坡土层非线性动力响应可能导致坡体不同位置的地震动加速度时程不一致,从而对整个滑动体的极限平衡状态及之后的地震累积永久位移产生影响。为了研究场地效应对边坡地震永久位移的影响,基于极限平衡条分法,通过对不同土条赋予不同的水平和竖向地震动时程,推导出一种考虑场地效应的圆弧和任意形状滑面的多点地震作用下边坡永久位移分析方法。通过与有限差分软件FLAC的数值模拟结果进行对比,验证了该方法能够合理考虑地震动的场地效应。通过研究不同分布形式的多点地震动及竖向地震动对边坡永久位移的影响,结果表明:场地效应引起的水平地震动放大以及多点地震动不同分布模式会导致整个滑体平均地震惯性力作用位置发生改变,从而影响地震作用下滑动体沿滑面的永久变形量,竖向地震动对边坡地震位移影响较小。将方法应用于Lexington土石坝震后变形案例分析,计算得到的坝坡地震永久位移与实际震后观测值相吻合,证明了考虑场地效应的重要性及本文方法的合理性。

关键词：地震边坡稳定性场地效应永久位移极限平衡条分法多点地震动

A 256×256 time-of-flight image sensor based on center-tap demodulation pixel structure

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Science China(Information Sciences) 2016年第4期59卷 132-141页

作者： Zhe CHEN Shan DI Zhongxiang cao Qi QIN fei ji Liyuan LIU Nanjian WU State Key Laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of Sciences

This paper proposes a 256×256 time-of-flight(TOF) image sensor based on the center-tap(CT)demodulation pixel structure. The image sensor can capture both the two-dimensional(2D) high speed image and the three-dimensional(3D) depth image. The CT pixel consists of two split pinned photodiode(PPD)regions and two pairs of transfer transistors. The transfer transistors adopt a non-uniform doped channel(NUDC) structure, which can increase the electron transfer speed along the transfer channel and eliminate the image lag for high speed imaging. The pixel size is 10 μm×10 μm, and we design the implementation process of the pixel to increase the electron transfer speed. The sensor is fabricated in a 0.18 μm 1P5 M CMOS image sensor process. Test results show that it can capture the 430-fps intensity image and the 90-fps depth image in two different imaging modes. The rectified non-linearity within the 1.0–7.5 m depth measurement range achieves less than 3 cm, and the measurement accuracy achieves 4.0 cm at 2.5 m, corresponding to the relative error of1.6%.

关键词： CMOS image sensor demodulation pixel depth image pinned photodiode time-of-flight(TOF)