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3D Progressive Damage Based Macro-Mechanical FE Simulation of Machining Unidirectional FRP Composite

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Chinese Journal of Mechanical Engineering 2018年第3期31卷 128-143页

作者： Yan-Li He Joao-Paulo Davim Hong-qian xue Key Laboratory of Contemporary Design and Integrated Manufacturing Technology of Ministry of Education School of Mechanical EngineeringNorthwestern Polytechnical University Department of Mechanical Engineering University of AveiroCampus Santiago

Finite element(FE) simulation is a powerful tool for investigating the mechanism of machining fiber?reinforced polymer composite(FRP). However in existing FE machining simulation works,the two?dimensional(2 D) progressive damage models only describe material behavior in plane stress,while the three?dimensional(3 D) damage models always assume an instantaneous sti ness reduction pattern. So the chip formation mechanism of FRP under machin?ing is not fully analyzed in general stress state. A 3 D macro?mechanical based FE simulation model was developed for the machining of unidirectional glass fiber reinforced plastic. An energy based 3 D progressive damage model was proposed for damage evolution and continuous sti ness degradation. The damage model was implemented for the Hashin?type criterion and Maximum stress criterion. The influences of the failure criterion and fracture energy dissipa?tion on the simulation results were studied. The simulated chip shapes,cutting forces and sub?surface damages were verified by those obtained in the reference experiment. The simulation results also show consistency with previous 2 D FE models in the reference. The proposed research provides a model for simulating FRP material behavior and the machining process in 3 D stress state.

关键词： FRP Macro mechanical Machining Finite element Progressive damage

Adversarial Attacks and Defenses in Deep Learning

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Engineering 2020年第3期6卷 346-360页

作者： Kui Ren Tianhang Zheng Zhan qin xue Liu Institute of Cyberspace Research Zhejiang UniversityHangzhou 310027China College of Computer Science and Technology Zhejiang UniversityHangzhou 310027China Department of Electrical and Computer Engineering University of TorontoTorontoON M5S 2E8Canada School of Computer Science McGill UniversityMontrealQC H3A 0E9Canada

With the rapid developments of artificial intelligence(AI)and deep learning(DL)techniques,it is critical to ensure the security and robustness of the deployed ***,the security vulnerability of DL algorithms to adversarial samples has been widely *** fabricated samples can lead to various misbehaviors of the DL models while being perceived as benign by *** implementations of adversarial attacks in real physical-world scenarios further demonstrate their ***,adversarial attack and defense techniques have attracted increasing attention from both machine learning and security communities and have become a hot research topic in recent *** this paper,we first introduce the theoretical foundations,algorithms,and applications of adversarial attack *** then describe a few research efforts on the defense techniques,which cover the broad frontier in the *** open problems and challenges are subsequently discussed,which we hope will provoke further research efforts in this critical area.

关键词： Machine learning Deep neural network Adversarial example Adversarial attack Adversarial defense

NLO Corrections of H_(TC)Π~0 and Π^+Π^- Pair Production at ILC in TC2 Model

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Communications in Theoretical Physics 2009年第8期52卷 311-317页

作者： QIAO qing-Peng LI Zuo LI xue-qian WANG xue-Lei Department of Physics Nankai University Tianjin 300071 China Department of Physics Henan Normal University Xinxiang 453007 China

As well known, if the Higgs boson were not observed at LHC, the technicolor model would be the most favorable candidate responsible for the symmetry breaking. To overcome some defects in the previous model, some extended versions have been proposed. In the TC2 model typical signature is existence of heavy HTC and technipion ∏. A direct proof of validity of the model is to produce them at accelerator. Thus we study the production rates of e＋e^- → HTC∏^0 and e＋e^- → ∏＋∏- at ILC in the topcolor-assisted technicolor （TC2） model. In fact, there is a flood of models belonging to new physics, which can result in products with characteristics similar to HTC ＋ ∏ of the TC2 model. Therefore to distinguish this model from others one may need to investigate some details by calculating the cross section to NLO. We indeed find that the NLO corrections are significant, namely the ratio δ ≡（ σNLO - σLO）/σLO in e＋e- →HTC∏^0 exceeds 100% within a plausible parameter space.

关键词： TC2 top-pion top-higgs LOOPTOOLS

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陕西中医 2025年第1期46卷 38-41页

作者：钱雅婷周雪朱轶庆南京市妇幼保健院产科江苏南京210000

目的:探讨丹益活血汤对产科抗磷脂综合征相关复发性流产(OAPS-RSA)患者血清黏蛋白域分子3(Tim-3)、半乳糖凝集素9(Gal-9)、晚期糖基化终末产物受体(RAGE)水平的影响。方法:选取128例OAPS-RSA患者,随机分为两组,对照组给予小剂量阿司匹林... 详细信息

目的:探讨丹益活血汤对产科抗磷脂综合征相关复发性流产(OAPS-RSA)患者血清黏蛋白域分子3(Tim-3)、半乳糖凝集素9(Gal-9)、晚期糖基化终末产物受体(RAGE)水平的影响。方法:选取128例OAPS-RSA患者,随机分为两组,对照组给予小剂量阿司匹林(LDA)联合低分子量肝素(LMWH)治疗,试验组加服丹益活血汤治疗,每组64例。比较两组疗效、治疗前后的子宫内膜容受性(ER)、血栓前状态(PTS)、血清Tim-3、Gal-9、RAGE水平及妊娠结局。结果:试验组总有效率更高(90.63%与76.56%)(P<0.05)。治疗后,与对照组比较,试验组EMT、Tim-3、Gal-9、RAGE均显著升高(P<0.05),PI、RI、FDP、D-D均显著降低(P<0.05)。试验组活产率高于对照组(P<0.05)。结论:丹益活血汤能够提升OAPS-RSA患者疗效,改善ER和PTS,升高血清Tim-3、Gal-9、RAGE水平,改善妊娠结局。

关键词：子宫内膜容受性复发性流产丹益活血汤产科抗磷脂综合征黏蛋白域分子3 半乳糖凝集素9

Emerging two-dimensional Mo-based materials for rechargeable metal-ion batteries:Advances and perspectives

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Journal of Energy Chemistry 2024年第2期89卷 487-518,I0012页

作者： qingqing Ruan Yuehua qian Mengda xue Lingyun Chen Qichun Zhang Department of Applied Chemistry School of Chemistry and Chemical EngineeringChongqing UniversityChongqing 401331China Department of Materials Science and Engineering City University of Hong Kong999077Hong KongChina

With the rapid development of rechargeable metal-ion batteries(MIBs)with safety,stability and high energy density,significant efforts have been devoted to exploring high-performance electrode *** recent years,two-dimensional(2D)molybdenum-based(Mo-based)materials have drawn considerable attention due to their exceptional characteristics,including low cost,unique crystal structure,high theoretical capacity and controllable chemical ***,like other transition metal compounds,Mo-based materials are facing thorny challenges to overcome,such as slow electron/ion transfer kinetics and substantial volume changes during the charge and discharge *** this review,we summarize the recent progress in developing emerging 2D Mo-based electrode materials for MIBs,encompassing oxides,sulfides,selenides,*** introducing the crystal structure and common synthesis methods,this review sheds light on the charge storage mechanism of several 2D Mo-based materials by various advanced characterization *** latest achievements in utilizing 2D Mo-based materials as electrode materials for various MIBs(including lithium-ion batteries(LIBs),sodium-ion batteries(SIBs)and zinc-ion batteries(ZIBs))are discussed in ***,the modulation strategies for enhancing the electrochemical performance of 2D Mo-based materials are highlighted,focusing on heteroatom doping,vacancies creation,composite coupling engineering and nanostructure ***,we present the existing challenges and future research directions for 2D Mo-based materials to realize high-performance energy storage systems.

关键词： Molybdenum-based materials Two-dimensional materials Lithium-ion batteries Sodium-ion batteries Zinc-ion batteries

Determining knots by optimizing the bending and stretching energies

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Applied Mathematics(A Journal of Chinese Universities) 2017年第1期32卷 53-67页

作者： ZHANG Fan qin xue-ying LI xue-mei CHENG Fu-hua Department of Computer Science and Technology Shandong Technology and Business University Department of Computer Science and Technology Shandong University Department of Computer Science University of Kentucky

For a given set of data points in the plane, a new method is presented for computing a parameter value（knot） for each data point. Associated with each data point, a quadratic polynomial curve passing through three adjacent consecutive data points is constructed. The curve has one degree of freedom which can be used to optimize the shape of the curve. To obtain a better shape of the curve, the degree of freedom is determined by optimizing the bending and stretching energies of the curve so that variation of the curve is as small as possible. Between each pair of adjacent data points, two local knot intervals are constructed, and the final knot interval corresponding to these two points is determined by a combination of the two local knot intervals. Experiments show that the curves constructed using the knots by the new method generally have better interpolation precision than the ones constructed using the knots by the existing local methods.

关键词： optimizing interpolation bending freedom stretching quadratic chord polynomial optimize Associated

A MIXED FE-BE METHOD FOR COUPLED VIBRATION OF GRAVITY DAM-RESERVOIR SYSTEM WITH VARIABLE WATER DEPTH

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Acta Mechanica Solida Sinica 1998年第2期11卷 123-132页

作者： Jin Tao Huang Yuying qian qin Huazhong Univ Sci & Technol Dept Mech Wuhan 430074 Peoples R China

To solve the coupled vibration of a gravity dam-reservoir systemwith variable water depth by using a hybrid element method, the fluidregion with variable water depth needs to be dis- cetized by FEmeshes. However, such a method asks for a great computational costowing to the ex- cessive unknowns, especially when the fluid regionwith variable water depth is relatively large. To overcome theshortcoming, a refined boundary element method is proposed to analyzethe fluid field, in which only the discretization for the boundary ofthe variable depth region is required. But as a basis of thisapproach, it is necessary to construct a new Green's functioncorresponding to an infinite strip region.

关键词： mixed FE-BE method fluid-solid interaction gravity dam

Nitrogen-Doped Hierarchical Heterostructured Aerophobic MoS_(x)/Ni_(3)S_(2)Nanowires by One-pot Synthesis:System Engineering and Synergistic Effect in Electrocatalysis of Hydrogen Evolution Reaction

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Energy & Environmental Materials 2021年第4期4卷 658-663页

作者： Xin Ma Wanru Chen qian Li Longjian xue Chuang Peng School of Resource and Environmental Sciences Wuhan UniversityWuhan 430072China The Institute of Technological Sciences Wuhan UniversityWuhan 430072China

Non-noble metal electrocatalysis has witnessed rapid and profound performance improvements owing to the emergence of advanced nanosynthetic *** of these nanotechniques can lead to synergistic performance enhancement,but such system-engineering strategies are difficult to achieve because of the lack of effective synthesis *** hereby demonstrate an integrated approach that combines most of the existing nanotechniques in a facile one-pot *** characterization reveals that the product shows key features intended by techniques including morphological,structural,doping,heterointerface,and surface wetting *** as-obtained nitrogen-doped hierarchical heterostructured MoS_(x)/Ni_(3)S_(2)nanowires show an overpotential that is only50 mV higher than commercial Pt/C for hydrogen evolution reaction over current densities from 10 to 150 mA cm^(-2).Correlations between the adopted nanotechniques and the electrochemical reaction rates are established by evaluating the impacts of individual techniques on the activation energy,pre-exponential factor,and transfer *** indepth analysis provides a full account of the synergistic effects and the overall improvement in electrocatalytic performance of hydrogen evolution *** work manifests a generic strategy for multipurpose material design in non-noble metal electrocatalysis.

关键词： electrochemical reaction rate nanotechnology non-noble metal catalysis synergistic effect system engineering

EXPERIMENTAL STUDY OF THE NON-DARCY FLOW AND SOLUTE TRANSPORT IN A CHANNELED SINGLE FRACTURE

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Journal of Hydrodynamics 2011年第6期23卷 745-751页

作者： CHEN Zhou qian Jia-zhong qin Hua School of Resources and Environmental Engineering Hefei University of Technology Hefei 230009 China

The characterization of fracture rocks is always a key issue in understanding the flow and solute transport in fractured media. This article studies the solute transport in a Channeled Single Fracture （CSF）, a single fracture with contact in certain areas. The flow in a CSF often has preferential pathways and the transport in a CSF often has Break Through Curves （BTCs） with long tails. The Surface Contact Ratio （SCR）, the ratio of the contact area to the total fracture area, is an important indicator for the fracture surface roughness. To study the flow and solute transport in a CSF, a controlled physical model is constructed and a series of flow and tracer test experiments are carried out. Under our experimental conditions, the flow in a CSF is found to follow the Forchheimer equation , where and are the hydraulic gradient and the average pore velocity, respectively and and are two parameters related to the viscous and inertial flow components, respectively. Furthermore, it is found that b decreases with the decrease of SCR. For the solute transport, it is found that the BTCs often deviate from the traditional Fickian behavior, by the early-arrival and the long tailing. More interestingly, the observed BTCs often have a double-peak or a multi-peak, that would be difficult to explain using the existing transport theory such as the Advection-Dispersion Equation （ADE）. In addition, the longitudinal dispersion coefficient is found to be scale-dependent in a CSF and the relationship is of exponential type.

关键词： channeled single fracture surface contact ratio non-Darcian non-Fickian