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Science China(Physics,Mechanics & Astronomy) 2014年第3期57卷 400-410页

作者： CHEN Cen LIANG NaiGang liu Fang fu qiang State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of Sciences School of Transportation Wuhan University of Technology China National Light Weight Gas Turbine Development Center

The elasto-plastic-damage behavior of anisotropic aluminum alloys is investigated under finite deformation using a physical mechanism based constitutive *** an application to the structural calculation,the present model is used to describe and analyze the mechanical response of anisotropic 6260-T6 aluminum alloy *** the tensile specimens extracted along three different material orientations from the extruded aluminum profile,twelve simulations are carried out covering four different specimen *** simulation results in force-displacement response and central logarithmic axial strain evolution are compared with experimental *** the comparisons,it can be concluded that the present model has the capacity to describe the behavior of anisotropic *** the force-displacement curves,the anisotropy is observed in different material orientations,and the physical mechanism of anisotropy is analyzed.

关键词： elasto-plastic-damage behavior anisotropy physical mechanism finite deformation constitutive theory componentassembling model

Numerical Analysis of the Flow Field in a Sloshing Tank with a Horizontal Perforated Plate

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Journal of Ocean University of China 2017年第4期16卷 575-584页

作者： JIN Heng liu Yong LI Huajun fu qiang Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100P.R.China CIMC Offshore Institute Co.Ltd. Yantai 264670P R.China

Liquid sloshing is a type of free surface flow inside a partially filled water *** exerts a significant effect on the safety of liquid transport systems;in particular,it may cause large hydrodynamic loads when the frequency of the tank motion is close to the natural frequency of the *** plates have recently been used to suppress the violent movement of liquids in a sloshing tank at resonant *** this study,a numerical model based on OpenF OAM(Open Source Field Operation and Manipulation),an open source computed fluid dynamic code,is used to investigate resonant sloshing in a swaying tank with a submerged horizontal perforated *** numerical results of the free surface elevations are first verified using experimental data,and then the flow characteristics around the perforated plate and the fluid velocity distribution in the entire tank are examined using numerical *** results clearly show differences in sloshing motions under first-order and third-order resonant *** study provides a better understanding of the energy dissipation mechanism of a horizontal perforated plate in a swaying tank.

关键词： sloshing horizontal perforated plate numerical simulation flow field energy dissipation

Lipomatous ependymoma with ZFTA:RELA fusion-positive:A case report

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World Journal of Clinical Cases 2025年第1期13卷 48-55页

作者： Xiao-Yu Zhao Juan-Han Yu Yi-Hua Wang Yi-Xin liu Lu Xu Lin fu Ning Yi China Medical University The First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina Department of Pathology The First Hospital of China Medical UniversityShenyang 110001Liaoning ProvinceChina Anshan Cancer Hospital Anshan 114000Liaoning ProvinceChina

BACKGROUND Ependymoma with lipomatous differentiation is a rare type of *** ZFTA fusion-positive supratentorial ependymoma is a novel tumor type in the 2021 World Health Organization classification of central nervous system *** fusion-positive lipomatous ependymoma has not been reported to *** SUMMARY We reported a case of a 15-year-old Chinese male who had a sudden convulsion lasting approximately six *** resonance imaging showed a round cystic shadow of approximately 1.9 cm×1.5 cm×1.9 cm under the right parieto-occipital *** examination showed characteristic perivascular pseudorosettes and adipose differentiation in the ***-chemical staining showed that the tumor cells were negative for cytokeratin,NeuN,Syn and p53,but positive for GFAP,vimentin and S-100 ***-ficant punctate intracytoplasmic EMA immunoreactivity was *** level of Ki-67 was about 5%.Genetic analysis revealed ZFTA:RELA fusion.A cranio-tomy with total excision of the tumor was *** follow-up time was 36 months,no evidence of disease recurrence was found in magnetic resonance *** Based on these findings,the patient was diagnosed as a ependymoma with ZFTA fusion and lipomatous *** case report provides information on the microscopic morphological features of ependymoma with ZFTA fusion and lipomatous differentiation,which can help pathologists to make a definitive diagnosis of this tumor.

关键词： Ependymoma Lipomatous Molecular classification Supratentorial ZFTA:RELA fusion Case report

Analysis of trends in testicular atrophy index values with age in patients with unilateral palpable cryptorchidism

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Asian Journal of Andrology 2022年第5期24卷 500-502页

作者： Pei-qiang Li Yan Huang fu-Yun liu Department of Pediatric Urology The Third Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China

Cryptorchidism affects the growth of testicular *** volume is associated with reproductive *** testicular atrophy index evaluates the degree of damage caused by cryptorchidism,but it remains unclear whether changes in testicular atrophy index are related to *** selected patients who underwent surgery for unilateral palpable *** volume was measured using *** testicular atrophy indices of the undescended testes were then reviewed,and their correlation with age was *** studied 228 cases(age range:6–53 months).Scatter plots were constructed,and Loess curves were fitted,revealing a turning point at 24 months of *** patients were divided into age groups of 6–24 months and 25–53 *** testicular volume of the cryptorchid side was smaller than that of the normal side in both groups(both P<0.001).In the 6–24-month group,the testicular atrophy index was positively correlated with age,testicular volume on the cryptorchid side was not correlated with age,and testicular volume was positively correlated with age on the normal *** the 25–53-month group,testicular atrophy index and testicular volumes on either side were not correlated with age.A palpable unilateral cryptorchid testis is smaller than the contralateral *** testicular atrophy index increases with age between 6 months and 24 months,but not between 25 months and 53 *** volume increased with age on the normal side between 6 months and 24 months,but not on the cryptorchid *** in testicular atrophy index with age contribute to the decision of operation time.

关键词： cryptorchidism testicular atrophy index testicular volume

Corrosion behavior of a spark plasma sintered Fe-2OMn-11Al-1.8C- 5Cr alloy in molten aluminum

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Journal of Iron and Steel Research International 2018年第5期25卷 563-571页

作者： Jian liu Wei-ping Chen Xian-man Zhang Zhi-qiang fu Guangdong Key Laboratory for Advanced Metallic Materials Processing South China University of TechnologyGuangzhou 510640 Guangdong China College of Engineering and Technology Normal College ofZunyi Zunyi 563006 Guizhou China Mechanical and Electrical Engineering College Hainan University Haikou 570228 Hainan China

The corrosion behavior of an Fe-20Mn-11Al-1.8C-5Cr alloy prepared by spark plasma sintering was investigated via immersion tests in molten aluminum at 750℃ for 1 and 4 h, respectively, and a hot work steel （AlSI H13） was included as a reference. The experimental results show that the corrosion rate of Fe-20Mn-11Al-1.8C-5Cr alloy is - 24% of that of H13 steel, suggesting that Fe-20Mn-11Al-1.8C-5Cr alloy in molten aluminum possesses better corrosion resistance than H13 steel. Detailed analysis show that k-carbide （（Fe, Mn）3AlCx） and Cr7C3 carbide precipitated in the matrix play a key role in enhancing the corrosion resistance of Fe-20Mn-11Al-1.8C-5Cr alloy in molten aluminum. Both of them show better corrosion resistance than 7-Fe matrix and H13 steel, and can also take on the role of roots in grasping the corrosion product and restrain them from spalling into the molten aluminum.

关键词： Fe-Mn-Al-C-Cr alloy · Molten aluminum. Immersion · Corrosion behavior

An enhanced treatment of boundary conditions in implicit smoothed particle hydrodynamics

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Acta Mechanica Sinica 2014年第1期30卷 37-49页

作者： Ya-Wei Han Hong-fu qiang Hu liu Wei-Ran Gao Xi’an Research Inst.of Hi-Tech.

In this work, an enhanced treatment of the solid boundaries is proposed for smoothed particle hydrodynamics with implicit time integration scheme （Implicit SPH）. Three types of virtual particles, i.e., boundary particles, image particles and mirror particles, are used to impose boundary conditions. Boundary particles are fixed on the solid boundary, and each boundary particle is associated with two fixed image particles inside the fluid domain and two fixed mirror particles outside the fluid domain. The image particles take the flow properties through fluid particles with moving least squares （MLS） interpolation and the properties of mirror particles can be obtained by the corresponding image particles. A repulsive force is also applied for boundary particles to prevent fluid particles from unphysical penetra- tion through solid boundaries. The new boundary treatment method has been validated with five numerical examples. All the numerical results show that Implicit SPH with this new boundary-treatment method can obtain accurate results for non-Newtonian fluids as well as Newtonian fluids, and this method is suitable for complex solid boundaries and can be easily extended to 3D problems.

关键词： Implicit SPH. Boundary conditions. Power-law model Repulsive force MLS interpolation

Monetary policy and dynamic adjustment of corporate investment: A policy transmission channel perspective

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China Journal of Accounting Research 2015年第2期8卷 91-109页

作者： qiang fu Xing liu School of Economics and Business Administration Chongqing University

We investigate monetary policy effects on corporate investment adjustment,using a sample of China's A-share listed firms(2005–2012), under an asymmetic framework and from a monetary policy transmission channel perspective. We find that corporate investment adjustment is faster in expansionary than contractionary monetary policy periods. Monetary policy has a significant effect on adjustment speed through monetary and credit channels. An increase in the growth rate of money supply or credit accelerates *** effects are significantly greater during tightening than expansionary periods. The monetary channel has significant asymmetry, whereas the credit channel has none. Leverage moderates the relationship between monetary policy and adjustment, with a greater effect in expansionary periods. This study enriches the corporate investment behavior literature and can help governments develop and optimize macro-control policies.

关键词： Monetary policy Transmission channels Asymmetric e

Posterior probability calculation procedure for recognition rate comparison

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Journal of Systems Engineering and Electronics 2016年第3期27卷 700-711页

作者： Jun He qiang fu Science and Technology on Automatic Target Recognition Laboratory College of Electronic Science and EngineeringNational University of Defense Technology

This paper focuses on the recognition rate comparison for competing recognition algorithms, which is a common problem of many pattern recognition research areas. The paper firstly reviews some traditional recognition rate comparison procedures and discusses their limitations. A new method, the posterior probability calculation（PPC） procedure is then proposed based on Bayesian technique. The paper analyzes the basic principle, process steps and computational complexity of the PPC procedure. In the Bayesian view, the posterior probability represents the credible degree（equal to confidence level） of the comparison results. The posterior probability of correctly selecting or sorting the competing recognition algorithms is derived, and the minimum sample size requirement is also pre-estimated and given out by the form of tables. To further illustrate how to use our method, the PPC procedure is used to prove the rationality of the experiential choice in one application and then to calculate the confidence level with the fixed-size datasets in another application. These applications reveal the superiority of the PPC procedure, and the discussions about the stopping rule further explain the underlying statistical causes. Finally we conclude that the PPC procedure achieves all the expected functions and be superior to the traditional methods.

关键词： pattern recognition performance evaluation algorithm uncertainty analysis

STABC-IR:An air target intention recognition method based on bidirectional gated recurrent unit and conditional random field with space-time attention mechanism

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Chinese Journal of Aeronautics 2023年第3期36卷 316-334页

作者： Siyuan WANG Gang WANG qiang fu Yafei SONG Jiayi liu Sheng HE Air Defense and Antimissile School Air Force Engineering UniversityXi’an 710051China

The battlefield environment is changing rapidly,and fast and accurate identification of the tactical intention of enemy targets is an important condition for gaining a decision-making *** current Intention Recognition(IR)method for air targets has shortcomings in temporality,interpretability and back-and-forth dependency of *** address these problems,this paper designs a novel air target intention recognition method named STABC-IR,which is based on Bidirectional Gated Recurrent Unit(Bi GRU)and Conditional Random Field(CRF)with Space-Time Attention mechanism(STA).First,the problem of intention recognition of air targets is described and analyzed in ***,a temporal network based on Bi GRU is constructed to achieve the temporal ***,STA is proposed to focus on the key parts of the features and timing information to meet certain interpretability requirements while strengthening the timing ***,an intention transformation network based on CRF is proposed to solve the back-and-forth dependency and transformation problem by jointly modeling the tactical intention of the target at each *** experimental results show that the recognition accuracy of the jointly trained STABC-IR model can reach 95.7%,which is higher than other latest intention recognition ***-IR solves the problem of intention transformation for the first time and considers both temporality and interpretability,which is important for improving the tactical intention recognition capability and has reference value for the construction of command and control auxiliary decision-making system.

关键词： Bidirectional gated recurrent network Conditional random field Intention recognition Intention transformation Situation cognition Space-time attention mechanism

Divergence-degenerate spatial multiplexing towards future ultrahigh capacity,low error-rate optical communications

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Light(Science & Applications) 2022年第6期11卷 1253-1263页

作者： Zhensong Wan Yijie Shen Zhaoyang Wang Zijian Shi qiang liu Xing fu Key Laboratory of Photonic Control Technology(Tsinghua University) Ministry of Education100084 BeijingChina State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua University100084 BeijingChina Optoelectronics Research center University of SouthamptonSouthampton SO171BJUK

Spatial mode(de)multiplexiing of orbital angular momentum(OAM)beams is a promising solution to address future bandwidth issues,but the rapidly increasing divergence with the mode order severely limits the practically addressable number of OAM *** we present a set of multi-vortex geometric beams(MVGBs)as high-dimensional information carriers for free-space optical communication,by virtue of three independent degrees of freedom(DoFs)including central OAM,sub-beam OAM,and coherent-state *** novel modal basis set has high divergence degeneracy,and highly consistent propagation behaviors among all spatial modes,capable of increasing the addressable spatial channels by two orders of magnitude than OAM basis as *** experimentally realize the tri-DoF MVGB mode(de)multiplexing and data transmission by the conjugated modulation method,demonstrating lower error rates caused by center offset and coherent background noise,compared with OAM *** work provides a potentially useful basis for the next generation of large-scale dense data communication.

关键词： optical error coherent