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Computer Modeling in Engineering & Sciences 2021年第2期126卷 715-738页

作者： Chao Ma Yunkai Gao Yuexing duan Zhe Liu School of Automotive Studies Tongji UniversityShanghai201804China

Stress-based topology optimization is one of the most concerns of structural optimization and receives much attention in a wide range of engineering *** solve the inherent issues of stress-based topology optimization,many schemes are added to the conventional bi-directional evolutionary structural optimization(BESO)method in the previous ***,these schemes degrade the generality of BESO and increase the computational *** study proposes an improved topology optimization method for the continuum structures considering stress minimization in the framework of the conventional BESO method.A global stress measure constructed by p-norm function is treated as the objective *** stabilize the optimization process,both qp-relaxation and sensitivity weight scheme are *** variables are updated by the conventional BESO *** 2D and 3D examples are used to demonstrate the validity of the proposed *** results show that the optimization process can be stabilized by *** value of q and p are crucial to reasonable *** proposed sensitivity weight scheme further stabilizes the optimization process and evenly distributes the stress *** computational efficiency of the proposed method is higher than the previous methods because it keeps the generality of BESO and does not need additional schemes.

关键词： Stress-based topology optimization aggregation function stress relaxation sensitivity weight bi-directional evolutionary structural optimization

Association between floods and hospital admissions for schizophrenia in Hefei,China:The lag effects of degrees of floods and time variation

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Association between floods and hospital admissions for schiz...

Brake Orbits of a Reversible Even Hamiltonian System Near an Equilibrium

安徽省2019年度流行病与卫生统计学学术年会

作者：魏倩楠 Zhang X Yi W Pan R Gao J duan J Xu Z Cheng q Bai L Zhang Y Su H 安徽医科大学公共卫生学院

BACKGROUND:Schizophrenia is a serious mental disorder,endangering 7.5 million patients in ***,as the adverse consequence of temperature-rise,have a negative influence on mental ***,the relationship between floods and schizophrenia is still *** study aimed to quantitative the relationship between floods and the admissions for schizophrenia in Hefei,***:A Poisson generalized linear model(GLM) combining a distributed lag non-linear model(DLNM) was used to quantify the lag effects of floods on schizophrenia and subgroups(male,female;≤40 y,>40 y;the married,the unmarried) from 2005 to 2014,Hefei,*** further explored the effects of different degrees(moderate and severe) of floods and their temporal changes on ***:There was a significant association between floods and admissions risk for *** the lag effects for schizophrenia lasted ten days(lag 5-lag 14),with the greatest effect on lag 9(RR=1.036,95% confidence interval(CI):1.014-1.058).The married,≤40 y were sensitive to *** significant difference wasn’t found for *** effects of the severe flood were higher than moderate floods,with the largest RR of 1.073(95%CI:1.029-1.119).The adverse effects were found in the middle and late period with a decreasing trend in the later ***:This study suggests a significant association between floods and schizophrenia with ten days of lag effects in Hefei,***,female,<40 y and the married are vulnerable to both moderate and severe *** findings might be used to allocate medical resources of mental health after floods.

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Acta Mathematica Sinica,English Series 2022年第1期38卷 263-280页

作者： Zhong Jie LIU Fan Jing WANG duan Zhi ZHANG School of Science Tianjin Chengjian UniversityTianjin 300384P.R.China School of Mathematics and Statistics Shanghai Lixin University of Accounting and FinanceShanghai 201209P.R.China School of Mathematical Sciences and LPMC Nankai UniversityTianjin 300071P.R.China

In this paper,we consider the brake orbits of a reversible even Hamiltonian system near an *** the Hamiltonian system(H S)x=J H(x)satisfies H(0)=0,H(0)=0,reversible and even conditions H(Nx)=H(x)and H(-x)=H(x)for all x∈R^(2n).Suppose the quadratic form q(x)=1/2 is ***τ_(0)>0 and assume that R^(2n)=E⊕F decomposes into linear subspaces E and F which are invariant under the flow associated to the linear system x=J H''(0)x and such that each solution of the above linear system in E isτ_(0)-periodic whereas no solution in F{0}isτ_(0)-***σ(τ_(0))=σ_q(τ_(0))for the signature of q|***σ(τ_(0))≠=0,we prove that either there exists a sequence of brake orbits x_k→0 withτk-periodic on the hypersurface H^(-1)(0)whereτ_k→τ_(0);or for eachλclose to 0 withλ_(σ)(τ_(0))>0 the hypersurface H-1(λ)contains at least 1/2|σ(τ_(0))|distinct brake orbits of the Hamiltonian system(HS)near 0 with periods nearτ_(0).Such result for periodic solutions was proved by Bartsch in 1997.

关键词： Brake orbits reversible Hamiltonian systems equilibrium even length and Conley index

基于影像的深度学习识别具有基因组和转录组异质性的胶质母细胞瘤危险分层：一项多中心研究

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国际医学放射学杂志 2023年第2期 244-245页

作者： J.Yan q.Sun X.Tan C.Liang H.Bai W.duan 李雷

摘要目的旨在开发并验证用于多形性胶质母细胞瘤（GBM）病人危险分层的影像深度学习预测模型（DLIS），并探索DLIS相关的生物学信号通路和基因突变变化。方法 DLIS

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Safety and immunogenicity of live attenuated hepatitis A virus vaccine (H2 strain) in humans

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中华医学杂志(英文版) 1993年第8期106卷 607-607页

作者： L A Ran D Z Wang q Y duan T Y Yan q L Liu Y G Luo D Z Yang D F Yang Z Xiao q J Xie Health and Anti-Epidemic Station of Sichuan Province Chengdu.

A study was made in Neijiang City, Sichuan Province to observe the safety and immunogenicity of a live attenuated hepatitis A virus (HAV) vaccine (H2 strain). 3,031 children, aged 6 to 9 years, were injected subcutaneously with 106.0 TCID50, 105.5 TCID50, and 105.0 TCID50 of HAV vaccine; the seroconversion rate and antibody GMT were 97.52%-90.68%, GMT=1:5.19±1.90-1:3.36±1.94; 84.75%-76.27%, GMT=1:4.29±1.96-1:2.0±2.67; 53.23%-51.61%, GMT=1:2.57±1.89-1:1.68±1.41 respectively after 4 weeks to 12 months of inoculation. Forty-eight children in the control group were anti-HAV negative at 4, 8, and 12 weeks; 21 children in the oral group were not antibody positive 4 and 8 weeks after oral administration of the vaccine. The stool specimens of 3 of the 14 vaccinated children were HAA positive. The results suggest that the live attenuated HAV vaccine (H2 strain) is of good immunogenicity and safety.

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Abnormal enhancement to the quality factors of carbon nanotube via defects engineering

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Nano Materials Science 2022年第3期4卷 259-265页

作者： Ke duan Li Li Sihan Liu Yujin Hu Xuelin Wang State Key Lab of Digital Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China

Low quality(q) factor is often the limiting factor for high performance carbon nanotube(CNT) resonators. The most commonly used approach to enhance the q factor of CNTs is to reduce/eliminate the intrinsic ***, we show surprisingly that hole defects of suitable size and position are able to enhance the q factor of CNT, which strongly contradicts to the common notion that the presence of defects promote intrinsic dissipation via defects dissipation. By analyzing the strain distribution, we find that such abnormal enhancement in q factor of defected CNT originates from a coupling competition mechanism between the atomic mismatch around defected atoms and the thermoelastic damping. Although the presence of holes will introduce an additional defect dissipation source, suitable holes are capable of reducing the energy dissipation arisen from the thermoelastic damping, through changing the spatial strain field of defected CNT. This coupling competition mechanism provides a new route for designing high performance CNT resonators via defects engineering.

关键词： Defects engineering CNT resonator q factor

Salt tolerance in rice:Physiological responses and molecular mechanisms

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The Crop Journal 2022年第1期10卷 13-25页

作者： Citao Liu Bigang Mao Dingyang Yuan Chengcai Chu Meijuan duan College of Agriculture Hunan Agricultural UniversityChangsha 410128HunanChina State Key Laboratory of Hybrid Rice Hunan Hybrid Rice Research CenterChangsha 410125HunanChina State Key Laboratory of Plant Genomics Institute of Genetics and Developmental BiologyThe Innovative Academy for Seed DesignChinese Academy of SciencesBeijing 100101China

Crop yield loss due to soil salinization is an increasing threat to agriculture *** stress drastically affects the growth,development,and grain productivity of rice(Oryza sativa L.),and the improvement of rice tolerance to salt stress is a desirable approach for meeting increasing food *** main contributors to salt toxicity at a global scale are Na^(+)and Cl^(-)ions,which affect up to 50%of irrigated *** responses to salt stress occur at the organismic,cellular,and molecular levels and are pleiotropic,involving(1)maintenance of ionic homeostasis,(2)osmotic adjustment,(3)ROS scavenging,and(4)nutritional *** this review,we discuss recent research progress on these four aspects of plant physiological response,with particular attention to hormonal and gene expression regulation and salt tolerance signaling pathways in *** information summarized here will be useful for accelerating the breeding of salt-tolerant rice.

关键词： Salt stress Rice(Oryza sativa L.) Salt tolerance genes Physiological response Salt signal transduction

Development of Cueing Algorithm Based on “Closed-Loop” Control for Flight Simulator Motion System

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Wuhan University Journal of Natural Sciences 2019年第5期24卷 376-382页

作者： ZHU Daoyang duan Shaoli FANG Da College of Intelligent Manufacturing Wuhan Technical College of Communications

The classical washout algorithm had fixed gains and manually constructed filters, so that it led to poor adaptability. Furthermore, it lost the sustained acceleration cues of high-and mid-frequency in cross-over(tilt-coordination) channel, and the acceleration of cross-over frequency was also limited by angular velocity limiter, so the false cues in flight simulation process were clearly perceived by pilots. The paper studied the characteristics of the classical washout algorithm and flight simulator motion platform, tried to redesign the source of cross-over acceleration channel and translation acceleration channel, and transferred the part of cross-over acceleration that was unsimulated sustained acceleration to translation acceleration channel. Comparisons were mainly made between classical washout algorithm and revised algorithm in a longitudinal/pitch direction. The evaluation was based on the implementation of human vestibular perception system. The results demonstrated that the revised algorithm could significantly reduce the phase lag, and improved the spikes tracking performance. Furthermore, sensory angular velocity and the error of sensory acceleration were strictly controlled within the threshold of human perception system, and the displacement was a little broader than the classical washout algorithm. Therefore, it was proved that the new algorithm could diminish the filters parameters and heighten the self-adaptability for the washout algorithm. In addition, the magnitude of false cues was remarkably reduced during flight simulator, and the workspace utilization of the motion platform was developed by "closed-loop" control system.

关键词： classical washout algorithm human vestibular system "closed-loop" control false cues

Changes in leaf nutrient traits and photosynthesis of four tree species: effects of elevated [CO_(2)], N fertilization and canopy positions

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Journal of Plant Ecology 2012年第4期5卷 376-390页

作者： Juxiu Liu Deqiang Zhang Guoyi Zhou Honglang duan Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China

Aims Leaf traits of trees exposed to elevated[CO_(2)]in association with other environmental factors are poorly understood in tropical and subtropical *** goal was to investigate the impacts of elevated[CO_(2)]and N fertilization on leaf traits in southern *** Four tree species,Schima superba *** Champ.(***),Ormosia pinnata(Lour.)Merr(***),Castanopsis hystrix ***.(***)and Acmena acuminatissima(Blume)*** Perry(***)were studied in a factorial combination of atmospheric[CO_(2)](ambient at~390μmol mol^(-1)and elevated[CO_(2)]at~700μmol mol^(-1))and N fertilization(ambient and ambient+100 kg N ha^(-1)year^(-1))in open-top chambers in southern China for 5 *** mass per unit leaf area(LMA),leaf nutrient concentration and photosynthesis(A_(sat))were *** Findings Results indicated that leaf traits and photosynthesis were affected differently by elevated[CO_(2)]and N fertilization among ***[CO_(2)]decreased LMA in all species,while N fertilization did not affect *** mass-based N concentration(N_(M))was significantly greater in *** and *** grown in elevated[CO_(2)]but was lower in *** mass-based P concentration(P_(M))was significantly greater in *** and *** exposed to elevated[CO_(2)]but was lower in ***.N fertilization significantly increased P_(M) in *** but decreased P_(M) in *** stimulation in ***,*** and *** was sustained after 5 years of CO_(2)fumigation.N fertilization did not modify the effects of elevated[CO_(2)]on *** traits(N_(M),N_(A),P_(M),P_(A))and light-saturated photosynthesis were decreased from the upper to lower *** position did not alter the responses of leaf traits and photosynthesis to elevated[CO_(2)].Results suggest that photosynthetic stimulation by elevated[CO_(2)]in native species in subtropical regions may be sustained in th

关键词： photosynthesis elevated CO_(2) nitrogen phosphorus subtropical China

Distributed Cooperative Secondary Voltage Control in an Unbalanced Microgrid

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 222-234页

作者： Xiangzhen Yang Haixi Zhao Mengke duan Yan Du Haining Wang Jian Zhang School of Electrical Engineering and Automation Hefei University of TechnologyHefei 23009China

The negative-sequence reactive power-conductance(q^(−)-G) droop control strategy is a conventional method to compensate for the output unbalanced voltages in an islanded ***, the conflict between unbalanced voltage compensation and negative-sequence reactive power sharing, caused bythe impedance mismatching of distribution lines and distributedgenerators, has not been solved only by q^(−)-G droop *** this paper, a distributed cooperative secondary unbalancedvoltage control strategy is proposed to decrease the outputvoltage unbalance factor (VUF) of each droop-controlled DG,as well as to further enhance the negative-sequence reactivepower sharing effectiveness among DGs by properly shiftingup and down the q^(−)-G droop characteristics of each *** algorithm for adaptive VUF weight coefficient is proposedto better suppress VUF under severe imbalance ***, a negative-sequence small-signal model of an MGunder an unbalanced condition, considering the communicationdelay time of the proposed SUVC, is established to analyze thesystem’s stability and transient performance under the influenceof some critical parameters. Finally, the effectiveness of theproposed strategy is validated by the simulation results froma real-time emulator of StarSim HIL.

关键词： Distributed cooperative control MG negativesequence reactive power starsim real-time platform time delay voltage unbalance compensation