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Failure evaluation and control factor analysis of slope block instability along traffic corridor in Southeastern Tibet

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Journal of Mountain Science 2024年第6期21卷 1830-1848页

作者： LIU Changqing BAO Han LAN Hengxing yan Changgen LI Changbo LIU shijie School of Highway Chang'an UniversityXi'an 710064China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Geological Engineering and Geomatics Chang'an UniversityXi'an 710054China

The instability of slope blocks occurred frequently along traffic corridor in Southeastern Tibet(TCST),which was primarily controlled by the rock mass structures.A rapid method evaluating the control effects of rock mass structures was proposed through field statistics of the slopes and rock mass structures along TCST,which combined the stereographic projection method,modified M-JCS model,and limit equilibrium theory.The instabilities of slope blocks along TCST were then evaluated rapidly,and the different control factors of instability were analyzed.Results showed that the probabilities of toppling(5.31%),planar(16.15%),and wedge(35.37%)failure of slope blocks along TCST increased sequentially.These instability modes were respectively controlled by the anti-dip joint,the joint parallel to slope surface with a dip angle smaller than the slope angle(singlejoint),and two groups of joints inclined out of the slope(double-joints).Regarding the control effects on slope block instability,the stabilization ability of doublejoints(72.7%),anti-dip joint(67.4%),and single-joint(57.6%)decreased sequentially,resulting in different probabilities of slope block instability.Additionally,nearby regional faults significantly influenced the joints,leading to spatial heterogeneity and segmental clustering in the stabilization ability provided by joints to the slope blocks.Consequently,the stability of slope blocks gradually weakened as they approached the fault zones.This paper can provide guidance and assistance for investigating the development characteristics of rock mass structures and the stability of slope blocks.

关键词： Slope engineering Block instability Rapid evaluation method Rock mass structure Control factor

The deteriorated degradation resistance of Mg alloy microtubes for vascular stent under the coupling effect of radial compressive stress and dynamic medium

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Journal of Magnesium and Alloys 2024年第2期12卷 573-585页

作者： Mengyao Liu Yabo Zhang Qingyuan Zhang yan Wang Di Mei Yufeng Sun Liguo Wang shijie Zhu Shaokang Guan School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Henan Key Laboratory of Advanced Magnesium Alloys Zhengzhou 450002China Key Laboratory of Advanced Materials Processing&Mold Ministry of Education Zhengzhou 450002China

The degradation of Mg alloys relates to the service performance of Mg alloy biodegradable implants.In order to investigate the degradation behavior of Mg alloys as vascular stent materials in the near service environment,the hot-extruded fine-grained Mg-Zn-Y-Nd alloy microtubes,which are employed to manufacture vascular stents,were tested under radial compressive stress in the dynamic Hanks'Balanced Salt Solution(HBSS).The results revealed that the high flow rate accelerates the degradation of Mg alloy microtubes and its degradation is sensitive to radial compressive stress.These results contribute to understanding the service performance of Mg alloys as vascular stent materials.

关键词： Mg alloy Microtubes Degradation behavior Radial compressive stress Dynamic conditions

Optimal Dispatch for Battery Energy Storage Station in Distribution Network Considering Voltage Distribution Improvement and Peak Load Shifting

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Journal of Modern Power Systems and Clean Energy 2022年第1期10卷 131-139页

作者： Xiangjun Li Rui Ma Wei Gan shijie yan State Key Laboratory of Control and Operation of Renewable Energy and Storage Systems China Electric Power Research InstituteBeijingChina College of Information and Engineering Northeastern UniversityShenyangChina

Distribution networks are commonly used to demonstrate low-voltage problems.A new method to improve voltage quality is using battery energy storage stations(BESSs),which has a four-quadrant regulating capacity.In this paper,an optimal dispatching model of a distributed BESS considering peak load shifting is proposed to improve the voltage distribution in a distribution network.The objective function is to minimize the power exchange cost between the distribution network and the transmission network and the penalty cost of the voltage deviation.In the process,various constraints are considered,including the node power balance,single/two-way power flow,peak load shifting,line capacity,voltage deviation,photovoltaic station operation,main transformer capacity,and power factor of the distribution network.The big M method is used to linearize the nonlinear variables in the objective function and constraints,and the model is transformed into a mixed-integer linear programming problem,which significantly improves the model accuracy.Simulations are performed using the modified IEEE 33-node system.A typical time period is selected to analyze the node voltage variation,and the results show that the maximum voltage deviation can be reduced from 14.06%to 4.54%.The maximum peak-valley difference of the system can be reduced from 8.83 to 4.23 MW,and the voltage qualification rate can be significantly improved.Moreover,the validity of the proposed model is verified through simulations.

关键词： Energy storage station distribution network voltage regulation peak load shifting mixed integer programming

Physics-informed deep learning for fringe pattern analysis

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Opto-Electronic Advances 2024年第1期7卷 4-15页

作者： Wei Yin Yuxuan Che Xinsheng Li Mingyu Li yan Hu shijie Feng Edmund Y.Lam Qian Chen Chao Zuo Smart Computational Imaging Laboratory(SCILab) School of Electronic and Optical EngineeringNanjing University of Science and TechnologyNanjing 210094China Smart Computational Imaging Research Institute(SCIRI)of Nanjing University of Science and Technology Nanjing 210019China Jiangsu Key Laboratory of Spectral Imaging&Intelligent Sense Nanjing 210094China Department of Electrical and Electronic Engineering The University of Hong KongPokfulamHong Kong SAR 999077China

Recently,deep learning has yielded transformative success across optics and photonics,especially in optical metrology.Deep neural networks (DNNs) with a fully convolutional architecture (e.g.,U-Net and its derivatives) have been widely implemented in an end-to-end manner to accomplish various optical metrology tasks,such as fringe denoising,phase unwrapping,and fringe analysis.However,the task of training a DNN to accurately identify an image-to-image transform from massive input and output data pairs seems at best naive,as the physical laws governing the image formation or other domain expertise pertaining to the measurement have not yet been fully exploited in current deep learning practice.To this end,we introduce a physics-informed deep learning method for fringe pattern analysis (PI-FPA) to overcome this limit by integrating a lightweight DNN with a learning-enhanced Fourier transform profilometry (Le FTP) module.By parameterizing conventional phase retrieval methods,the Le FTP module embeds the prior knowledge in the network structure and the loss function to directly provide reliable phase results for new types of samples,while circumventing the requirement of collecting a large amount of high-quality data in supervised learning methods.Guided by the initial phase from Le FTP,the phase recovery ability of the lightweight DNN is enhanced to further improve the phase accuracy at a low computational cost compared with existing end-to-end networks.Experimental results demonstrate that PI-FPA enables more accurate and computationally efficient single-shot phase retrieval,exhibiting its excellent generalization to various unseen objects during training.The proposed PI-FPA presents that challenging issues in optical metrology can be potentially overcome through the synergy of physics-priors-based traditional tools and data-driven learning approaches,opening new avenues to achieve fast and accurate single-shot 3D imaging.

关键词： optical metrology deep learning physics-informed neural networks fringe analysis phase retrieval

“In-N-out” design enabling high-content triethyl phosphate-based non-flammable and high-conductivity electrolytes for lithium-ion batteries

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Science China Chemistry 2024年第2期67卷 724-731页

作者： Mengchuang Liu Fenfen Ma Zicheng Ge Ziqi Zeng Qiang Wu Hui yan Yuanke Wu Sheng Lei yanli Zhu shijie Cheng Jia Xie State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan430074China School of Chemistry and Chemical Engineering Huazhong University of Science and TechnologyWuhan430074China GuSu Laboratory of Materials Suzhou215123China Institute of Metal Research Chinese Academy of SciencesShenyang110000China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

Safety issues related to flammable electrolytes in lithium-ion batteries(LIBs) remain a major challenge for their extended applications.The use of non-flammable phosphate-based electrolytes has proved the validity in inhibiting the combustion of LIBs.However,the strong interaction between Li^(+) and phosphate leads to a dominant solid electrolyte interphase(SEI) with limited electronic shielding,resulting in the poor Li^(+) intercalation at the graphite(Gr) anode when using high-phosphate-content electrolytes.To mitigate this issue and improve Li^(+) insertion,we propose an “In-N-Out” strategy to render phosphates “noncoordinative”.By employing a combination of strongly polar solvents for a “block effect” and weakly polar solvents for a “drag effect”,we reduce the Li^(+)–phosphate interaction.As a result,phosphates remain in the electrolyte phase(“In”),minimizing their impact on the incompatibility with the Gr electrode(“Out”).We have developed a non-flammable electrolyte with high triethyl phosphate(TEP) content(>60 wt.%),demonstrating the excellent ion conductivity(5.94 mS cm^(-1) at 30 ℃) and reversible Li^(+) intercalation at a standard concentration(~1 mol L^(-1)).This approach enables the manipulation of multiple electrolyte functions and holds the promise for the development of safe electrochemical energy storage systems using non-flammable electrolytes.

关键词： lithium-ion batteries graphite anode high-phosphate-content electrolytes non-flammable electrolyte excellent ion conductivity standard concentration

Updated prevalence of latent prostate cancer in Chinese population and comparison of biopsy results: An autopsy-based study

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The Innovation 2024年第1期5卷 80-87页

作者： Yuliang Chen Zhien Zhou Yi Zhou Zhipeng Mai shijie Jin Zhen Liang Zhiyuan Shang Yuzhi Zuo Yu Xiao Wenze Wang Haibo Wang Weigang yan Department of Urology Peking Union Medical College HospitalChinese Academy of Medical SciencesBeijing 100730China Department of Gynaecology and Obstetrics Beijing HospitalNational Centre of GerontologyBeijing 100730China Department of Pathology Peking Union Medical College HospitalChinese Academy of Medical SciencesBeijing 100730China Peking University Clinical Research Institute Peking University First HospitalBeijing 100034China

Prostate cancer detected by autopsy is named latent prostate cancer.As the repertoire of clinical prostate cancer,latent cancer may better reflect the disease burden.Unlike clinical prostate specimens,which are obtained exclusively from biopsy-positive cases,prostate specimens obtained through autopsy provide information on biopsy-negative cases,helping calculate the true sensitivity of prostate biopsy.From 2014 to 2021,we collected autopsy specimens of the prostate from body donors in China and performed transperineal and transrectal biopsies on specimens before step-sectioning and pathological measurements.We found that the crude prevalence of latent prostate cancer in middle-aged and elderly men was 35.1%(81/231),which was higher than previous estimates for Chinese populations.The overall per-patient sensitivities of transperineal and transrectal biopsies were not significantly different(33.3%vs.32.1%,p=0.82),but the two approaches differed in preferential sampling area along the proximal-distal axis of the prostate.Transperineal biopsy had a higher sensitivity for detecting clinically significant lesions in the distal third(34.7%vs.16.3%,p=0.02)and distal half(30.6%vs.18.1%,p=0.04),while transrectal biopsy had a higher sensitivity for lesions in the proximal half(25.0%vs.13.9%,p=0.046).Both transperineal and transrectal methods of biopsy missed most small lesions(0.5 mL).In conclusion,the prevalence of latent prostate cancer in China has increased over the past 2 decades.Systematic transperineal and transrectal methods of biopsy had comparable sensitivities but had different preferential sampling areas.Both approaches miss one-third of large lesions.

关键词： biopsy prevalence latent

Emission and optical characteristics of brown carbon in size-segregated particles from three types of Chinese ships

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Journal of Environmental Sciences 2024年第8期142卷 248-258页

作者： Fengqin yang Fan Zhang Zeyu Liu Yingjun Chen yan Zhang Can Wu Yali Lei shijie Liu Binyu Xiao Xinyi Wan Yubao Chen Yong Han Min Cui Cheng Huang Gehui Wang Key Lab of Geographic Information Science of the Ministry of Education School of Geographic SciencesEast China Normal UniversityShanghai 200241China Institute of Eco-Chongming 20 Cuiniao Rd.ChongmingShanghai 202150China State Environmental Protection Key Laboratory of Formation and Prevention of the Urban Air Pollution Complex Shanghai Academy of Environmental SciencesShanghai 200233China Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200438China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China Department of Civil and Environmental Engineering and State Key Laboratory of Marine Pollution The Hong Kong Polytechnic UniversityKowloon 100872Hong KongChina College of Environmental Science and Engineering Yangzhou UniversityYangzhou 225009China

Brown carbon(BrC)is one of the important light absorption substances that have high light absorption ability under short wavelength light.However,limit studies have focused on the BrC emission from ships.In this study,size-segregated particulate matters(PM)were collected from three different types of ships,light absorption characteristics and size distribution of methanol-soluble BrC and water-soluble BrC in PM from ship exhausts were investigated.Results showed that four-stroke low-power diesel fishing boat(4-LDF)had the highest mass concentrations of methanol-soluble organic carbon(MSOC)and water-soluble organic carbon(WSOC),followed by 2-stroke high-power heavy-fuel-oil vessel(2-HHV),and fourstroke high-power marine-diesel vessel(4-HMV).While 2-HHV had obviously higher light absorption coefficients of methanol-soluble BrC(Abs365,M)and water-soluble BrC(Abs365,W)in unit weight of PM than the other two types of ships.The tested ships presented comparable or higher absorption efficiency of BrC in water extracts(MAE365,W)compared with other BrC emission sources.Majority of BrC was concentrated in fine particles,and the particle size distributions of both Abs365,Mand Abs365,Wshowed bimodal patterns,peaking at0.43–0.65μm and 4.7–5.8μm,respectively.However,different particle size distributions were found for MAE365,Mbetween diesel and heavy fuel oil ships.Besides,different wavelength dependence in particles with different size were also detected.Ship exhaust could be confirmed as a non-ignorable BrC emission source,and complex influencing factor could affect the light absorption characteristics of ship emissions.Particle size should also be considered when light absorption ability of BrC was evaluated.

关键词： Ship emission Brown carbon Light absorption Size distribution

Aluminum and Activated Alumina Powder Additions on Microwave Synthesis of Al_(4)SiC_(4)

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China's Refractories 2024年第1期33卷 44-48页

作者： WANG Li LIU shijie WEI Haoyu MA Juanjuan DONG Binbin GENG Shangrui yan Miaoxin QIN Feng GUO Yusen Henan Key Laboratory of Green Building Materials Manufacturing and Intelligent Equipemnt Luoyang Institute of Science and TechnologyLuoyang 471023China

Aiming at improving the properties of magnesia carbon materials,silicon aluminum carbide(Al_(4)SiC_(4))containing materials were prepared using industrial aluminum powder,silicon carbide powder,and graphite as raw materials,and activated alumina powder as an additive,mixing thoroughly,pressing into cylinders and then firing at 1200℃for 30 min in a carbon embedded atmosphere by the microwave method.The effects of the aluminum powder addition(20%and 24%,by mass)and activated alumina powder addition(0,3%,5%and 7%,by mass)on the microwave synthesis of Al_(4)SiC_(4) as well as the effect of the obtained Al_(4)SiC_(4) containing material on the properties of magnesia carbon bricks were studied.The results show that:compared with the samples with 20%aluminum powder,those with 24%aluminum powder generate more Al_(4)SiC_(4).With the activated alumina powder addition increasing from 0 to 7%,the amount of Al_(4)SiC_(4) generated increases first and then decreases.Compared with the sample without activated alumina powder,the samples with activated alumina powder show lower bulk density and higher apparent porosity.With the activated alumina powder addition increasing from 3%to 7%,the bulk density of the samples increases first and then decreases,while the apparent porosity of the samples shows an opposite trend.The optimal additions are 24%aluminum powder and 5%activated alumina powder,and Al_(4)SiC_(4) synthesized in this sample has a hexagonal plate structure.With the synthesized Al_(4)SiC_(4) containing material added,the magnesia carbon brick has slightly increased cold modulus of rupture,basically the same modulus of elasticity and improved oxidation resistance.

关键词： aluminum powder activated alumina powder microwave synthesis Al_(4)SiC_(4) magnesia carbon bricks

Forest status assessment in China with SDG indicators based on high-resolution satellite data

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International Journal of Digital Earth 2023年第1期16卷 1008-1021页

作者： Xiaomei Zhang Guojin He shijie yan Tengfei Long Xueli Peng Zhaoming Zhang Guizhou Wang China Remote Sensing Satellite Ground Station Aerospace Information Research InstituteChinese Academy of SciencesBeijingPeople’s Republic of China School of Electrical and Communication Engineering University of Chinese Academy of SciencesBeijing100049People’s Republic of China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049People’s Republic of China

To assess the status and change trend of forest in China,an indicator framework was developed using SDG sub-indicators.In this paper,we propose an improved methodology and a set of workflows for calculating SDG indicators.The main modification include the use of moderate and high spatial resolution satellite data,as well as state-of-the-art machine learning techniques for forest cover classification and estimation of forest above-ground biomass(AGB).This research employs GF-1 and GF-2 data with enhanced texture information to map forest cover,while time series Landsat data is used to estimate forest AGB across the whole territory of China.The study calculate two SDG sub-indicators:SDG_(15.1.1) for forest area and SDG_(15.2.1) for sustainable forest management.The evaluation results showed that the total forest area in China was approximately 219 million hectares at the end of 2021,accounting for about 23.51%of the land area.The average annual forest AGB from 2015 to 2021 was estimated to be 105.01Mg/ha,and the overall trend of forest AGB change in China was positive,albeit with some spatial differences.

关键词： Remote sensing sustainability forest status assessment SDG_(15.1.1) SDG_(15.2.1)