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Journal of Mountain Science 2023年第5期20卷 1249-1265页

作者： wanG Kai ZHANG shao-jie XIE wan-li GUAN Hui School of Architecture and Civil Engineering Zhongyuan University of TechnologyZhengzhou 450007China Department of Geology State Key Laboratory of Continental DynamicsNorthwest UniversityXi′an 710069China Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China

Slope units is an effective mapping unit for rainfall landslides prediction at regional *** present,slope units extracted by hydrology and morphological method report very different morphological feature and *** order to investigate the effect of morphological difference on the prediction performance,this paper presents a general landslide probability analysis model for slope *** Carlo method was used to describe the spatial uncertainties of soil mechanical parameters within slope units,and random search technique was performed to obtain the minimum safety factor;transient hydrological processes simulation was used to provide key hydrological parameters required by the model,thereby achieving landslide prediction driven by quantitative precipitation estimation and forecasting *** prediction performance of conventional slope units(CSUs)and homogeneous slope units(HSUs)were analyzed in three case studies from Fengjie County,*** results indicate that the mean missing alarm rate of CSUs and HSUs are 31.4% and 10.6%,*** Operating Characteristics(ROC)analysis also reveals that HSUs is capable of improving the overall prediction performance,and may be used further for rainfall-induced landslide prediction at regional scale.

关键词： Slope unit Boundaries Slope gradient Landslide prediction

On the superplastic deformation mechanisms of near-αTNW700 titanium alloy

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Journal of Materials Science & Technology 2022年第13期108卷 173-185页

作者： Lixia Ma Min wan Weidong Li Jie shao Xiaoning Han Jichun Zhang School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China AVIC Manufacturing Technology Institute Beijing 100024China

The new near-αTNW700 titanium alloy is a potential candidate material for high performance ultrasonic/hypersonic aircrafts,which is designed for short-term service at 700℃.This study systematically investigated the superplastic deformation microstructure evolution and mechanism of TNW700 alloy at different strain rates and true strains at 925℃.Results show that TNW700 alloy exhibits excellent superplastic behavior in a constant strain rate range of 0.0005-0.005 s^(-1) with elongation above 400%.The peak stress decreases with decreasing strain rate,which is related to the increase ofβ-phase volume fraction caused by the increase of thermal exposure *** addition,significant strain hardening is observed in early-middle stage of superplastic deformation,and flow softening is followed in middle-late *** rationalize these complex flow behaviors,electron backscatter diffraction(EBSD)and high resolution transmission electron microscopy(HRTEM)were used to characterize the *** hardening is correlated to the synergistic effect ofβgrain growth,dislocation accumulation,silicide precipitate,and solid solution strengthening ofα*** dynamic recrystallization(CDRX)induced the fragmentation of primaryαgrains in middle-late stage of superplastic deformation,and the refinement ofαgrains,the increase ofβphase volume fraction and dynamic dislocation recovery are main causes of high strain *** addition,EBSD and TEM observations confirmed texture randomization,fine equiaxed primaryαgrains and intragranular dislocation movement,indicating that grain boundary sliding(GBS)accommodated by dislocation sliding/climb is the dominant superplastic deformation mechanism of TNW700 alloy.

关键词： Near-αtitanium alloy Superplastic deformation Strain hardening and flow softening Microstructure evolution Deformation mechanisms

Layered Double Hydroxides for Oxygen Evolution Reaction towards Efficient Hydrogen Generation

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Energy Material Advances 2022年第1期2022卷 101-117页

作者： Xin wan Yingjie Song Hua Zhou Mingfei shao State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China

Electrochemical water splitting is one of the effective ways to obtain highly pure ***,as one of the two half reactions,oxygen evolution reaction(OER)has a high overpotential,resulting in the low-energy utilization ***,numerous electrocatalysts have been developed to reduce the energy barrier of *** them,layered double hydroxides(LDHs)are excellent OER electrocatalysts with flexible composition and structure,which have been widely investigated in the past *** studies have been focusing on the identification of active sites for LDHs during OER process,trying to reveal clear reaction mechanism for designing more efficient LDHs ***,this review tries to discuss the advances in identifying active site of LDHs based OER electrocatalysts for efficient hydrogen *** first introduce the effect of structure,composition,and defects to the OER performance of ***,main attention is paid on the active sites and mechanisms during OER,especially the coordination structures and catalytic mechanisms of active *** the end of this review,we put forward the existing problems and shortcomings in this fields,and propose the corresponding solutions,aiming to further promote the development of outstanding OER electrocatalysts towards efficient hydrogen production.

关键词： Oxygen hydroxide shortcomings

Cooperative localization method for multi-robot based on PF-EKF

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Science in China(Series F) 2008年第8期51卷 1125-1137页

作者： wanG Ling wan JianWei LIU YunHui shao JinXin School of Electronic Science and Engineering National University of Defense Technology Changsha410073 China

A method of cooperative localization for multi-robot in an unknown environment is described. They share information and perform localization by using relative observations and necessary communication. At initial time, robots do not know their positions. Once the robot that can obtain the absolute position information has its position, other robots use particle filter to fuse relative observations and maintain a set of samples respectively representing their positions. When the particles are close to s Gsussian distribution after a number of steps, we switch to an EKF to track the pose of the robots. Simulation results and real experiment show that PF-EKF method combines the robustness of PF and the efficiency of EKF. Robots can share the absolute position information and effectively localize themselves in an unknown environment.

关键词： cooperative localization relative observation particle filter EKF

Total Routhian Surface Calculations on Hf Isotopes

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Communications in Theoretical Physics 2008年第8期50卷 459-462页

作者： YU shao-Ying LI Yan-Xia SHEN Cai-wan College of Science Huzhou Teachers College Huzhou 313000 China College of Mathematics Physics and Information Engineering Zhejiang Normal University Jinhua 321000 China Institute of Theoretical Physics the Chinese Academy of Sciences Beijing 100080 China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000China

The two-dimensional total routhian surface calculations have been carried out to stud）, the triaxial superdeformed structure of a neutron-rich nucleus ^173 Hf firstly. In particular the effects of the rotational frequency ω and pairing-energy gap parameter A are discussed in detail in the course of shaping its triaxial superdeformation; additionally the neutron-shell correction energy is analyzed with emphasis in the confirmed triaxial superdeformed nucleus ^173Hf. Finally, more systematical results have been investigated for some confirmed superdeformed nuclei experimentally and a few predicted triaxial superdeformed nuclei theoretically with quadropole deformation ε2 ≈0.4 and triaxial deformation γ≈20° or 30° in the Z = 72 region.

关键词： triaxial superdeformed nucleus total routhian surface

Diabetic mastopathy in an elderly woman misdiagnosed as breast cancer: A case report and review of the literature

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World Journal of Clinical Cases 2021年第14期9卷 3458-3465页

作者： Xiao-Xiao Chen Shi-Jun shao Hua wan Department of Breast Shuguang HospitalShanghai University of Traditional Chinese MedicineShanghai 200001China

BACKGROUND Diabetic mastopathy is a rare benign disease in clinical practice that mainly occurs in young and middle-aged women with type 1 *** has also been reported that this disease can be found in patients with type 2 diabetes and other autoimmune diseases,such as Hashimoto's thyroiditis,as well as in *** pathogenesis of diabetic mastopathy is not yet clear,and it is easily confused with breast cancer due to their similar clinical manifestations and imaging *** SUMMARY A 69-year-old female patient was admitted because of painless breast masses,with a history of type 2 *** imaging and physical examination suggested a high risk of breast *** histopathological analysis showed dense lymphocytes infiltrating around the lobules of the breast,and extensive fibrosis of the surrounding ***,diabetic mastopathy was *** The diagnosis of diabetic mastopathy in elderly patients with painless breast masses is difficult to distinguish from breast cancer,and its imaging manifestations are not specific.

关键词： Diabetic mastopathy Diabetes Mammary gland disease Literature review Autoimmunity Case report

Reanalyzing Pentaquark Θ^＋（1540） in Framework of QCD Sum Rules Approach with Direct Instantons

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Communications in Theoretical Physics 2006年第2期45卷 320-324页

作者： wanG Zhi-Gang YANG Wei-Min wan shao-Long Department of Physics North China Electric Power University Baoding 071003 China Department of Modern Physics University of Science and Technology of China Hefei 230026 China

In this article, we study the pentaquark state Θ＋（1540） with a （scalar） diquark-（pseudoscalar） diquarkantiquark type interpolating current in the framework of the QCD sum rules approach by including the contributions from the direct instantons. The numerical results indicate that the contributions from the direct instantons are very small and can be safely neglected.

关键词： QCD sum rules instanton pentaquark state

The Influence of Ultrasonic Frequency on the Properties of Ni-Co Coatings Prepared by Ultrasound-assisted Electrodeposition

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Acta Metallurgica Sinica(English Letters) 2013年第6期26卷 735-741页

作者： Minqi SHENG Chenkai LV Lan HONG Mingwang shao Kang wan Fan LV School of Iron and Steel Soochow University Institute of Functional Nano & Soft Materials (FUNSOM) Soochow University

In this paper, Ni-Co coatings were electrodeposited onto carbon steel substrates with the aid of ultrasonic agitation. The coatings were analyzed by energy dispersive X-ray analysis （EDX）, X-ray diffraction analysis （XRD） and scanning electron microscopy （SEM）. The effects of the ultrasonic frequency on the roughness, hardness and corrosion resistance of the Ni-Co coatings were also investigated. The results indicated that the increase of the ultrasonic frequency from 20 to 120 kHz reduced the Ni content and the grain size of Ni-Co coatings. Moreover, the phase structure of the electrodeposited coatings was influenced by the ultrasonic frequency. Under 55 kHz ultrasonic agitation, the Ni-Co coating was single fcc phase and showed the finest roughness and the strongest corrosion resistance in 5 wt.% NaCl solution at the ambient temperature. Under ultrasonic agitation with frequency of 90 kHz, the coating was a mixture of fcc and hcp structure and showed the maximal hardness of about 420 HV. Therefore, ultrasonic agitation helped decrease the roughness, and enhance hardness and corrosion resistance of Ni-Co coatings.

关键词： Ni-Co alloys Coatings Electrodeposition Ultrasound Hardness Corrosion

Calculation of the π Meson Electromagnetic Form Factor

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Chinese Physics Letters 2001年第6期18卷 743-745页

作者： wanG Zhi-Gang wan shao-Long wanG Ke-Lin Center for Nonlinear Science University of Science and Technology of ChinaHefei 230026 Department of Astronomy and Applied Physics University of Science and Technology of ChinaHefei 230026

The modified flat-bottom potential(MFBP)is given by the combination of the flat-bottom potential with considerations for the infrared and ultraviolet asymptotic behaviour of the effective quark-gluon ***πmeson electromagnetic form factor is calculated in the framework of coupled Schwinger-Dyson equation and Bethe-Salpeter equation in simplified impulse approximation(dressed vertex)with *** our numerical results give good fit to experimental values.

关键词： equation vertex simplified

Reduced precision solution criteria for nonlinear model predictive control with the feasibility-perturbed sequential quadratic programming algorithm

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第11期12卷 919-931页

作者： Jiao-na wan Zhi-jiang shao Ke-xin wan Xue-yi FANG Zhi-qiang wanG Ji-xin QIAN State Key Lab of Industrial Control Technology Institute of Industrial Control Department of Control Science and Engineering Zhejiang University Hangzhou 310027 China

We propose a novel kind of termination criteria, reduced precision solution (RPS) criteria, for solving optimal control problems (OCPs) in nonlinear model predictive control (NMPC), which should be solved quickly for new inputs to be applied in time. Computational delay, which may destroy the closed-loop stability, usually arises while non-convex and nonlinear OCPs are solved with differential equations as the constraints. Traditional termination criteria of optimization algorithms usually involve slow convergence in the solution procedure and waste computing resources. Considering the practical demand of solution precision, RPS criteria are developed to obtain good approximate solutions with less computational cost. These include some indices to judge the degree of convergence during the optimization procedure and can stop iterating in a timely way when there is no apparent improvement of the solution. To guarantee the feasibility of iterate for the solution procedure to be terminated early, the feasibility- perturbed sequential quadratic programming (FP-SQP) algorithm is used. Simulations on the reference tracking performance of a continuously stirred tank reactor (CSTR) show that the RPS criteria efficiently reduce computation time and the adverse effect of computational delay on closed-loop stability.

关键词： Nonlinear model predictive control (NMPC) Computational delay Termination criteria Continuously stirred tankreactor (CSTR)