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输入受限乘波体飞行器无估计预设性能控制

空军工程大学学报 2024年第2期25卷 39-47页

作者：罗瑞宁何广军卜祥伟孙昭空军工程大学防空反导学院西安710051

针对输入受限的乘波体飞行器跟踪控制问题,提出了一种无估计的预设性能控制方法。首先,针对可能发生的执行器饱和问题,设计了一种新型抗饱和补偿系统。然后,利用补偿系统状态构造新的预设性能转换误差,基于预设性能控制与反演控制的方法... 详细信息

针对输入受限的乘波体飞行器跟踪控制问题,提出了一种无估计的预设性能控制方法。首先,针对可能发生的执行器饱和问题,设计了一种新型抗饱和补偿系统。然后,利用补偿系统状态构造新的预设性能转换误差,基于预设性能控制与反演控制的方法,为速度子系统与高度子系统设计了无需估计的低复杂度控制器。该设计方法的优越性在于无需状态估计与神经逼近,显著降低了控制的复杂度与计算量。基于Lyapunov稳定理论证明了所有转换误差与跟踪误差最终一致有界。最后,通过数值仿真验证了所提方法的有效性。

关键词：乘波体飞行器预设性能控制反演控制抗饱和补偿系统输入受限无估计控制

新时代促进西部城市高校毕业生就地就业对策研究——以西安市为例

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教育教学论坛 2024年第20期 41-44页

作者：许璐孙赵勇西安理工大学经济管理学院陕西西安710054

现阶段,西部地区与东部地区发展差距依然较大,要解决我国人力资源区域间失衡的问题,缩小区域经济发展差距,人才是根本。针对西部城市对本市高校毕业生吸引力不足的问题,以西安市为例,通过分析新时代促进西部高校毕业生就地就业的重要意... 详细信息

现阶段,西部地区与东部地区发展差距依然较大,要解决我国人力资源区域间失衡的问题,缩小区域经济发展差距,人才是根本。针对西部城市对本市高校毕业生吸引力不足的问题,以西安市为例,通过分析新时代促进西部高校毕业生就地就业的重要意义,新时代西部高校毕业生就业存在的问题,深度挖掘影响高校毕业生就地就业的关键因素,提出促进西部高校毕业生就地就业的对策,为西部城市人才引进工作、高校就业创业提供一定的理论参考与现实借鉴。

关键词：西部高校高校毕业生就地就业人才引进

蒙特卡罗模拟中物理模型对质子硼俘获治疗剂量学的影响

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强激光与粒子束 2024年第6期36卷 150-156页

作者：吴骏翔邓力源何贞岑孙钊胡智民四川大学原子核科学技术研究所辐射物理及技术教育部重点实验室成都610064 四川省肿瘤医院电子科技大学附属肿瘤医院成都610041

比较了蒙特卡罗(MC)软件Geant4中不同物理过程对质子硼俘获治疗(PBCT)的剂量学影响。选取Geant4中FTFP、QBBC和QGSP三种物理过程,构建包含质子硼核反应的质子剂量沉积的模型,比较了80 MeV质子束选取三种物理过程在有无硼时的剂量分布,以... 详细信息

比较了蒙特卡罗(MC)软件Geant4中不同物理过程对质子硼俘获治疗(PBCT)的剂量学影响。选取Geant4中FTFP、QBBC和QGSP三种物理过程,构建包含质子硼核反应的质子剂量沉积的模型,比较了80 MeV质子束选取三种物理过程在有无硼时的剂量分布,以及3 MeV质子束轰击纯硼时的核反应产物数据。三种物理过程在有无硼时水模体中的剂量分布无显著差异,一致性较好。FTFP物理过程获得的质子硼核反应产物与QBBC和QGSP物理过程相比差异较大。而QGSP物理过程得到的α粒子的产额、平均能量和能量范围与QBBC物理过程相比与实际情况吻合更好。综合评估三种物理过程中使用的非弹性散射模型以及模拟得到的核反应产物数据,Geant4中的QGSP物理过程更适用于PBCT的MC模拟研究。

关键词：质子硼俘获治疗蒙特卡罗模拟 Geant4 剂量学核反应产物

A Thermodynamic Perspective on Polymer Glass Formation

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Chinese Journal of Polymer Science 2023年第9期41卷 1329-1341,I0004页

作者： Wen-Sheng Xu zhao-Yan sun State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China

The dynamics of polymeric and other glass-forming liquids dramatically slows down upon cooling toward the glass transition temperature without any obvious significant change in their static structure.A quantitative understanding of this extraordinary dynamic slowdown remains one of the most significant challenges in condensed matter physics.Historically,extensive efforts have been devoted to explaining the dynamics of glass-forming liquids in terms of thermodynamic properties,leading to a number of semi-empirical models emphasizing distinct thermodynamic properties.Here,a thermodynamic perspective is provided on the glass formation of polymeric and other materials.We begin with an overview of the thermodynamic models of glass formation,including the intuitively appealing“free volume”models,enthalpy models originally emphasized by Goldstein and later by others,and the highly influential configurational entropy-based models.The review of these models is followed by a discussion of the advances that attempt to bring together some of the seemingly disparate thermodynamic viewpoints on glass formation by revealing a close interrelation between thermodynamic properties.We conclude this review with remarks on several key topics in this field,along with our viewpoint for future work.

关键词： Glass formation Entropy Free volume Enthalpy

Fluorescent Silk Obtained by Feeding Silkworms with Fluorescent Materials

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Chinese Journal of Chemistry 2023年第16期41卷 2035-2046页

作者： zhao-Fan Wu zhao-Nan sun Huan-Ming Xiong Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan UniversityShanghai 200438China

Comprehensive Summary Fluorescent silk has potential application in many fields such as bioimaging,tissue engineering scaffolds,luminescent marks,and dazzling fabrics.Among the methods to endow natural silk with fluorescent properties,feeding silkworms with fluorescent additives is facile,low-cost and environment friendly,which has the prospect of large-scale production.In this paper,we reviewed the research progress for this aim in the past ten years,and summarized the unified characteristics for the substances that can enter the silk gland by digestive tract of silkworms.The advantages and disadvantages of various fluorescent materials for this application are compared in detail.And the future research directions are suggested to overcome the shortcomings of the present research.

关键词： Fluorescent silk Fluorescent materials Feeding silkworms Carbon dots Nanoparticles Nanotechnology Multi-color emission Bioimaging

A Numerical Study on the Water Impact of the Rigid/Elastic Box-Like Structure

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China Ocean Engineering 2023年第2期37卷 333-342页

作者： YANG Jian sun zhao-chen LIANG Shu-xiu State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

Recent damages to the box-like structures caused by wave slamming have made it necessary to study the impact problems of this kind of structure. This paper showed findings from numerical simulations of the rigid/elastic structures, aiming to gain insights into the characteristics of the problem. The results of the rigid cases showed the significance of air compressibility during the impact process, while the slamming phenomena became quite different without the effect. In the elastic cases, the trapped air made the structure vibrate at frequencies much smaller than its eigenfrequencies. Besides, the structural deformation made it easy for the trapped air to escape outwards, which weakened the air cushioning effect, especially at high impact velocities. The above analysis gives the results when the structural symmetry axis was vertical to the water(vertical impacts). In addition, the results were given when the axis was oblique to the water(oblique impacts). Compared with the vertical cases, the impact phenomena and structural response showed asymmetry. This work used the computational fluid dynamics(CFD) method to describe fluid motion and the finite element method(FEM) for the deformable structure. A two-way coupling approach was used to deal with the fluid-structure interaction in the elastic cases.

关键词： water impact fluid-structure interaction air compressibility box-like structures two-way coupling

BM-MSCs延缓CD8^(+)初始T细胞衰老

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基础医学与临床 2024年第5期44卷 683-689页

作者：高竞溪赵晓妍朱星雨孙昭韩钦赵春华中国医学科学院基础医学研究所、北京协和医学院基础学院、中国医学科学院组织工程研究中心北京100005 中国医学科学院、北京协和医学院、北京协和医院肿瘤内科北京100730

目的验证骨髓间充质干细胞(BM-MSCs)缓解免疫衰老的作用,探究其衰老改善的主要免疫细胞群体。方法分离获得小鼠脾淋巴细胞,刺激增殖7d构建复制性衰老细胞模型。利用流式细胞测量术检测年轻对照组、复制性衰老对照组和BM-MSCs共培养组T... 详细信息

目的验证骨髓间充质干细胞(BM-MSCs)缓解免疫衰老的作用,探究其衰老改善的主要免疫细胞群体。方法分离获得小鼠脾淋巴细胞,刺激增殖7d构建复制性衰老细胞模型。利用流式细胞测量术检测年轻对照组、复制性衰老对照组和BM-MSCs共培养组T细胞亚群衰老标志物p16ink4a(p16)和p21cip1(p21)的表达水平。结果T淋巴细胞复制性衰老模型中观察到持续增殖后CD8^(+)T细胞较CD4^(+)T细胞衰老显著,在CD8^(+)T细胞的初始细胞、效应细胞亚群中,效应细胞衰老最显著;BM-MSCs共培养对衰老的效应细胞没有明显影响,主要通过延缓初始T细胞的衰老,达到缓解CD8^(+)T细胞衰老的作用(P<0.01,P<0.001)。结论与BM-MSCs共培养可以缓解T细胞的复制性衰老表型,对CD8^(+)T细胞的抗衰作用更显著,主要通过抑制初始T细胞的衰老实现。

关键词：骨髓间充质干细胞(BM-MSCs) T细胞衰老延缓衰老

基于DEA-Malmquist模型的临沂市农业生产效率研究

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江西农业学报 2024年第4期36卷 93-99页

作者：孙铭茹李藩涛孙兆明青岛农业大学经济管理学院(合作社学院) 山东青岛266109

选取2013—2021年临沂市各县区农业生产要素的投入、产出面板数据,基于投入导向的DEA-BCC模型对临沂市农业生产效率进行了测算与评价,使用Malmquist指数对临沂市农业全要素生产率进行了测算与分解,并从动态变化角度分析了农业生产效率... 详细信息

选取2013—2021年临沂市各县区农业生产要素的投入、产出面板数据,基于投入导向的DEA-BCC模型对临沂市农业生产效率进行了测算与评价,使用Malmquist指数对临沂市农业全要素生产率进行了测算与分解,并从动态变化角度分析了农业生产效率的年际变化趋势。结果表明:临沂市各县区的农业生产效率差异较大、总体水平较低,且多数县区处于规模报酬递增趋势;临沂市农业全要素生产率提升的动力主要源于技术进步,且年均增长率呈上升趋势。鉴于此,提出了优化生产要素投入,提升规模效率;加强农业技术的研发与推广,促进农业技术进步;加大财政支出力度,提高农业生产效率等政策建议。

关键词：农业生产效率 DEA模型 Malmquist指数临沂市

Therapeutic effect of two methods on avulsion fracture of tibial insertion of anterior cruciate ligament

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World Journal of Clinical Cases 2022年第27期10卷 9641-9649页

作者： Hai-Ming Niu Qing-Chun Wang Rui-zhao sun Department of Orthopedics Guanyun People's HospitalLianyungang 222200Jiangsu ProvinceChina

BACKGROUND The tibial stop of anterior cruciate ligament(ACL) is fan-shaped and attached to the medial groove in front of the intercondylar spine,which is located between the anterior horn of the medial and lateral meniscus.The incidence of this fracture is low previously reported,which is common in children and adolescents.With the increase of sports injury and traffic injury and the deepening of understanding,it is found that the incidence of the disease is high at present.AIM To explore the difference between open reduction and internal fixation with small incision and high-intensity non-absorbable suture under arthroscopy in the treatment of tibial avulsion fracture of ACL.METHODS Seventy-six patients with tibial avulsion fracture of anterior cruciate ligament diagnosed and treated in Guanyun County People’s Hospital from April 2018 to June 2020 were retrospectively analyzed.According to the surgical methods,they were divided into group A(40 cases) and group B(36 cases).Patients in group A were treated with arthroscopic high-strength non-absorbable suture,and patients in group B were treated with small incision open reduction and internal fixation.The operation time,fracture healing time,knee joint activity and functional score before and after operation,and surgical complications of the two groups were compared.RESULTS The operation time of group A was higher than that of group B,and the difference was statistically significant(P 0.05);The knee joint function activity was compared between two groups before operation,3 mo and 6 mo after operation,and the difference was not statistically significant(P > 0.05);the knee joint function activity of group A and group B at 3 mo and 6 mo after operation was significantly higher than that before operation(P < 0.05);the limp,support,lock,instability,swelling,upstairs,squatting,pain and Lysholm score were compared between the two groups

关键词： Small incision Anterior cruciate ligament Open reduction and internal fixation Arthroscopy Non-absorbable sutures Anterior cruciate ligament tibial avulsion fracture