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New formula for predicting the plastic buckling pressure of steel torispherical heads under internal pressure

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第8期25卷 618-630页

作者： sheng ye Keming LI Jinyang ZHENG Shan SUN Institute of Process Equipment Zhejiang UniversityHangzhou 310027China Engineering Research Center for High Pressure Process Equipment and Safety of Ministry of Education Hangzhou 310027China State Key Laboratory of Fluid Power and Mechatronic Systems Hangzhou 310058China

Thin-walled torispherical heads under internal pressure can fail by plastic buckling because of compressive circumferential stresses in the head ***,existing formulas still have limitations,such as complicated expressions and low accuracy,in determining buckling *** this paper,we propose a new formula for calculating the buckling pressure of torispherical heads based on elastic-plastic analysis and experimental ***,a finite element(FE)method based on the arc-length method is established to calculate the plastic buckling pressure of torispherical heads,considering the effects of material strain hardening and geometrical *** buckling pressure results calculated by the FE method in this paper have good consistency with those of BOSOR5,which is a program for calculating the elastic-plastic bifurcation buckling pressure based on the finite difference energy ***,the effects of geometric parameters,material parameters,and restraint form of head edge on buckling pressure are ***,a new formula for calculating plastic buckling pressure is developed by fitting the curve of FE results and introducing a reduction factor determined from experimental ***,based on the experimental results,we compare the predictions of the new formula with those of existing *** is shown that the new formula has a higher accuracy than the existing ones.

关键词： Torispherical head Plastic buckling Elastic-plastic analysis Prediction formula Finite element method

Calibration of line structured light vision system based on camera’s projective center

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光学精密工程 2005年第5期13卷 584-591页

作者： ZHU Ji-gui LI Yan-jun ye sheng-hua State Key Laboratory of Precision Measuring Technology and Instrument Tianjin Universality Tianjin 300072China

Based on the characteristics of line structured light sensor, a speedy method for the calibration was established. With the coplanar reference target, the spacial pose between camera and optical plane can be calibrated by using of the camera’s projective center and the light’s information in the camera’s image surface. Without striction to the movement of the coplanar reference target and assistant adjustment equipment, this calibration method can be implemented. This method has been used and decreased the cost of calibration equipment, simplified the calibration procedure, improved calibration efficiency. Using experiment, the sensor can attain relative accuracy about 0.5%, which indicates the rationality and effectivity of this method.

关键词：投影中心线性结构光传感器标度可视性系统

Crystal structure of kindlin-2 PH domain reveals a conformational transition for its membrane anchoring and regulation of integrin activation

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Protein & Cell 2012年第6期3卷 434-440页

作者： Yan Liu Yun Zhu sheng ye Rongguang Zhang National Laboratory of Biophysics Institute of BiophysicsChinese Academy of SciencesBeijing 100101China

Kindlin-2 belongs to a subfamily of FERM domain con-taining proteins,which plays key roles in activating integrin transmembrane receptors and mediating cell *** to conventional FERM domains,kindlin-2 FERM contains an inserted pleckstrin homology(PH)domain that specifically binds to phosphatidy-linositol(3,4,5)trisphosphate(PIP3)and regulates the kindlin-2 *** have determined the crystal struc-ture of kindlin-2 PH domain at 1.9Åresolution,which reveals a conserved PH domain fold with a highly charged and open binding pocket for PIP3 head *** comparison with a previously reported solution structure of kindlin-2 PH domain bound to PIP3 head group reveals that upon PIP3 insertion,there is a significant conformational change of both the highly positively charged loop at the entry of the PIP3 binding pocket and the entireβbarrel of the PH *** propose that such“induced-fit”type change is crucial for the tight binding of PIP3 to anchor kindlin-2 onto the membrane surface,thereby promoting its binding to *** results provide important structural insight into kindlin-2-mediated membrane anchoring and integrin activation.

关键词： kindlin-2 integrin PH domain crystal structure cell adhesion membrane

A neural network protocol for predicting molecular bond energy

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Science China Chemistry 2019年第12期62卷 1698-1703页

作者： Chao Feng Edward Sharman sheng ye Yi Luo Jun Jiang Hefei National Laboratory for Physical Sciences at the Microscale Department of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China Department of Neurology University of CaliforniaIrvineCalifornia 92697USA

Molecular bond energy is a key parameter for analyzing the properties of chemical activity,stability and *** bond energy is a challenge due to the cost of first-principles simulations and unsatisfactory prediction using empirical *** we show that a neural network(NN)machine-learning method can achieve quick prediction of bond energies of organic *** atomic species and charge information as descriptors,we trained a NN protocol and applied it to predict the bond energy in a certain chemical bond that agreed with density functional theory *** protocol also provided a way to evaluate the effects of different methods of atomic charge analysis on NN *** to accurately estimate bond energies,this NN protocol provides a cost-effective tool for optimizing chemical reactions,accelerating molecular design,and other important applications.

关键词： bond energy neural network density functional theory

Changes of tear film and tear secretion after phacoemulsification in diabetic patients

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第4期9卷 324-328页

作者： Xi LIU Yang-shun GU ye-sheng XU Ophthalmology Center the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective: To evaluate tear film stability and tear secretion in patients with diabetes after phacoemulsification. Methods: Twenty-five diabetic cataract patients and 20 age-matched non-diabetic cataract patients as control underwent pha- coemulsification. Tear film break-up time (TFBUT), Schirmer I test (SIT), corneal fluorescein staining, and dry eye symptoms were measured pre- and postoperatively. Results: Diabetics had a decreased preoperative TFBUT and SIT. TFBUT was reduced on Day 1 and recovered on Day 180 postoperatively in both groups. SIT was increased after phacoemulsification, but returned to preoperative levels by Day 180 in non-diabetics, whereas it was lower than preoperative level in diabetics. Positive corneal fluo- rescein staining was elevated in both groups, and returned to preoperative levels only in controls. Dry eye symptoms were similar to fluorescein staining in both groups. Conclusion: Tear secretion was reduced in diabetic cataract patients after phacoe- mulsification, which worsened dry eye symptoms and predisposed those patients to ocular damage.

关键词： Phacoemulsification Diabetes Cataract Tear

Robust Text Detection in Natural Scenes Using Text Geometry and Visual Appearance

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International Journal of Automation and computing 2014年第5期11卷 480-488页

作者： sheng-ye Yan Xin-Xing Xu Qing-Shan Liu School of Information and Control Nanjing University of Information Science and Technology School of Computer Engineering Nanyang Technological University

This paper proposes a new two-phase approach to robust text detection by integrating the visual appearance and the geometric reasoning rules. In the first phase, geometric rules are used to achieve a higher recall rate. Specifically, a robust stroke width transform(RSWT) feature is proposed to better recover the stroke width by additionally considering the cross of two strokes and the continuousness of the letter border. In the second phase, a classification scheme based on visual appearance features is used to reject the false alarms while keeping the recall rate. To learn a better classifier from multiple visual appearance features, a novel classification method called double soft multiple kernel learning(DS-MKL) is proposed. DS-MKL is motivated by a novel kernel margin perspective for multiple kernel learning and can effectively suppress the influence of noisy base kernels. Comprehensive experiments on the benchmark ICDAR2005 competition dataset demonstrate the effectiveness of the proposed two-phase text detection approach over the state-of-the-art approaches by a performance gain up to 4.4% in terms of F-measure.

关键词： Text detection geometric rule stroke width transform (SWT) support vector machine (SVM) multiple kernel learning (MKL)

Machine learning aided design of perovskite oxide materials for photocatalytic water splitting

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Journal of Energy Chemistry 2021年第9期30卷 351-359页

作者： Qiuling Tao Tian Lu ye sheng Long Li Wencong Lu Minjie Li Department of Chemistry College of SciencesShanghai UniversityShanghai 200444China Materials Genome Institute Shanghai UniversityShanghai 200444China

Suffering from the inefficient traditional trial-and-error methods and the huge searching space filled by millions of candidates, discovering new perovskite visible photocatalysts with higher hydrogen production rate(RH_(2)) still remains a challenge in the field of photocatalytic water splitting(PWS). Herein, we established structural-property models targeted to RH_(2) and the proper bandgap(Eg) via machine learning(ML) technology to accelerate the discovery of efficient perovskite photocatalysts for PWS. The Pearson correlation coefficients(R) of leave-one-out cross validation(LOOCV) were adopted to compare the performances of different algorithms including gradient boosting regression(GBR), support vector regression(SVR), backpropagation artificial neural network(BPANN), and random forest(RF). It was found that the BPANN model showed the highest R values from LOOCV and testing data of 0.9897 and 0.9740 for RH_(2),while the GBR model had the best values of 0.9290 and 0.9207 for Eg. Furtherly, 14 potential PWS perovskite candidates were screened out from 30,000 ABO3-type perovskite structures under the criteria of structural stability, Eg, conduction band energy, valence band energy and RH_(2). The average RH_(2) of these14 perovskites is 6.4% higher than the highest value in the training data set. Moreover, the online web servers were developed to share our prediction models, which could be accessible in http://***/ocpmdm/material_api/ahfga3d9puqlknig(E_g prediction) and http://***/ocpmdm/material_api/i0 ucuyn3 wsd14940(RH_(2) prediction).

关键词： Perovskite Machine learning Online web service Photocatalytic water splitting Bandgap Hydrogen production rate

Accelerating H^(*)desorption of hollow Mo_(2)C nanoreactor via in-situ grown carbon dots for electrocatalytic hydrogen evolution

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Journal of Energy Chemistry 2024年第9期96卷 464-471页

作者： Mengmeng Liu Yuanyuan Jiang Zhuwei Cao Lulu Liu Hong Chen sheng ye School of Materials and Chemistry Anhui Agricultural UniversityHefei 230036AnhuiChina

Molybdenum carbide(Mo_(2)C)is a promising non-noble metal electrocatalyst with electronic structures similar to Pt for hydrogen evolution reaction(HER).However,strong H^(*)adsorption at the Mo sites hinders the improvement of HER ***,we synthesized monodisperse hollow Mo_(2)C nanoreactors,in which the carbon dots(CD)were in situ formed onto the surface of Mo_(2)C through carburization *** to finite element simulation and analysis,the CD@Mo_(2)C possesses better mesoscale diffusion properties than Mo_(2)C *** optimized CD@Mo_(2)C nanoreactor demonstrates superior HER performance in alkaline electrolyte with a low overpotential of 57 mV at 10 mA cm^(−2),which is better than most Mo_(2)C-based ***,CD@Mo_(2)C exhibits excellent electrochemical stability during 240 h,confirmed by operando Raman and X-ray diffraction(XRD).Density functional theory(DFT)calculations show that carbon dots cause the d-band center of CD@Mo_(2)C to shift away from Fermi level,promoting water dissociation and the desorption of H^(*).This study provides a reasonable strategy towards high-activity Mo-based HER eletrocatalysts by modulating the strength of Mo–H bonds.

关键词： Mo_(2)C nanoreactor Carbon dots H^(*)desorption Electrocatalytic hydrogen evolution

Microstructure and properties of silica-based ceramic cores by laser powder bed fusion combined with vacuum infiltration

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Journal of Materials Science & Technology 2023年第26期157卷 71-79页

作者： Jie Zhang Jia-Min Wu Heng Liu Wen Zheng Chun-sheng ye Shi-Feng Wen Chun-Ze Yan Yu-sheng Shi State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Engineering Research Center of Ceramic Materials for Additive Manufacturing Ministry of EducationWuhan 430074China

The silica-based ceramic core has attracted much attention in the preparation of hollow blades due to its great *** this paper,the silica-based ceramic cores reinforced with ZrSiO_(4) were prepared by laser powder bed fusion(LPBF)combined with vacuum infiltration(VI).To enhance the infiltration effect,the pre-sintered bodies with high porosity and hydrophilicity were obtained by pre-sintering at 1100℃.Results showed that a large number of silica particles infiltrated into the pre-sintered *** infiltrated silica promoted the generation of liquid phase in sintering,thereby promoting the removal of pores and the connection of ***,the dispersed ZrSiO_(4) grains prevented the viscous flow of the liquid phase,thereby increasing the ***_(4) grains could hinder the propagation of cracks due to their high *** the addition of ZrSiO_(4) was 10 wt.%,room-temperature flexural strength of silica-based ceramic cores infiltrated with slurry S1(the mass ratio of silica sol to silica powder was 10:1)reached 17.21 MPa due to the reinforcement of sintering ***,high-temperature flexural strength reached 13.90 ***,the pre-sintering process could greatly improve the mechanical properties of silica-based ceramic cores prepared by LPBF-VI technology.

关键词： Silica-based ceramic cores Laser powder bed fusion ZrSiO_(4) Pre-sintering Vacuum infiltration