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主动可调谐压电超材料梁的宽带振动抑制优化

Acta Mechanica Sinica 2024年第3期40卷 202-213页

作者：高玉强王立峰 State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China

压电超材料在带隙调控方面已经得到了广泛的应用,然而,在工程应用中,宽带振动抑制是仍存在着挑战.在本文中,设计了一中包含多个压电单元的压电超胞结构,并提出一种压电超材料梁的优化方法用于拓宽超材料振动抑制的频率范围.采用遗传算... 详细信息

压电超材料在带隙调控方面已经得到了广泛的应用,然而,在工程应用中,宽带振动抑制是仍存在着挑战.在本文中,设计了一中包含多个压电单元的压电超胞结构,并提出一种压电超材料梁的优化方法用于拓宽超材料振动抑制的频率范围.采用遗传算法对压电单元中的LR分流电路进行优化.通过优化将多个局部共振带隙耦合到布拉格带隙中.同时可定制超材料的衰减常数,并优化得到最大带宽.为验证优化方法的正确性以及宽频振动抑制能力,利用合成电路模拟LR电路中的可调电感,通过调节电感,实验实现了可调节的振动抑振能力.实验结果还表明,优化后的超材料可拓宽振动抑制频率范围.实验验证了超材料宽频可调节的振动抑振能力.本文为宽带振动抑制提供了一种新的方法和途径.

关键词： Optimization Broadband vibration suppression Piezoelectric metamaterial Tunable bandgap

Physical mechanism of secondary-electron emission in Si wafers

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Chinese Physics B 2024年第4期33卷 677-681页

作者：赵亚楠孟祥兆彭淑婷苗光辉高玉强彭斌崔万照胡忠强 State Key Laboratory for Manufacturing Systems Engineering Electronic Materials Research LaboratoryKey Laboratory of the Ministry of EducationEngineering Research Center of Spin Quantum Sensor ChipsUniversities of Shaanxi ProvinceSchool of Electronic Science and EngineeringXi'an Jiaotong UniversityXi'an 710049China College of Aeronautics Nanjing University of Aeronautics and AstronauticsNanjing 210016China National Key Laboratory of Science and Technology on Space Microwave China Academy of Space TechnologyXi'an 710100China Department of Physics School of Physics and Electronic InformationAnhui Normal UniversityWuhu 241000China

CMOS-compatible RF/microwave devices,such as filters and amplifiers,have been widely used in wireless communication ***,secondary-electron emission phenomena often occur in RF/microwave devices based on silicon(Si)wafers,especially in the high-frequency *** this paper,we have studied the major factors that influence the secondary-electron yield(SEY)in commercial Si wafers with different doping *** show that the SEY is suppressed as the doping concentration increases,corresponding to a relatively short effective escape depthλ.Meanwhile,the reduced narrow band gap is beneficial in suppressing the SEY,in which the absence of a shallow energy band below the conduction band will easily capture electrons,as revealed by first-principles ***,the new physical mechanism combined with the effective escape depth and band gap can provide useful guidance for the design of integrated RF/microwave devices based on Si wafers.

关键词： secondary-electron yield doping concentration escape depth Si wafer

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双磁性谐振子可调超材料的带隙耦合特性研究

固体力学学报 2024年第3期45卷 313-325页

作者：杨宇辰王立峰俞潇高玉强南京航空航天大学航空航天结构力学及控制全国重点实验室南京210016

弹性波超材料是一种人工周期结构,可应用于航空航天、车辆工程等领域的减振降噪.本文设计了一种可以产生耦合带隙具有两个磁性谐振子的超材料.该超材料采用不锈钢薄板连接磁振子与外部框架,调节磁铁之间距离可以影响不锈钢薄板的面内应... 详细信息

弹性波超材料是一种人工周期结构,可应用于航空航天、车辆工程等领域的减振降噪.本文设计了一种可以产生耦合带隙具有两个磁性谐振子的超材料.该超材料采用不锈钢薄板连接磁振子与外部框架,调节磁铁之间距离可以影响不锈钢薄板的面内应力从而影响内部刚度.通过调节元胞结构,形成相邻两元胞内部刚度不同的双胞系统,从而实现更宽的耦合带隙.得到了不锈钢薄板提供的刚度和磁力提供的负刚度随磁铁间距的变化关系.建立了双磁性谐振子可调单胞超材料和由调节磁铁距离构成的双胞超材料的频散关系和传递率理论模型.计算了磁铁距离改变对超材料带隙结构的影响以及特定情况下的双胞耦合带隙结果.设计并利用3D打印技术制作了实验模型,测得了不同磁铁距离下的传递率曲线并且验证了双胞超材料结构的带隙耦合结果.理论预测的传递率与实验结果吻合良好.所提出的模型可以为超材料的主动调控以及可编程性提供新的思路.

关键词：超材料可调谐负刚度磁性振子带隙耦合

科技金融政策、业绩预期差距与企业大数据应用——基于不同期望参照水平的检验

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山东财经大学学报 2024年第4期36卷 86-98页

作者：高玉强王子帅张宇青岛大学经济学院山东青岛266071 东北财经大学金融学院辽宁大连116025

在新一代信息技术和各产业不断融合发展的背景下,如何促进大数据应用成为企业战略决策研究的关键环节.基于企业行为理论和业绩反馈理论,将科技金融试点政策纳入企业探索式创新的前因要素模型,并深入探讨业绩预期差距的调节作用.利用2007... 详细信息

在新一代信息技术和各产业不断融合发展的背景下,如何促进大数据应用成为企业战略决策研究的关键环节.基于企业行为理论和业绩反馈理论,将科技金融试点政策纳入企业探索式创新的前因要素模型,并深入探讨业绩预期差距的调节作用.利用2007—2020年中国A股上市公司数据,基于2011年和2016年多批次科技金融试点政策的自然实验采用倍差法分析发现:科技金融政策具有创新效应,显著提高了试点区域内企业的大数据应用水平;行业业绩期望落差扩大时,企业通过战略变革恢复市场支配力的动机更为强烈,能够正向调节科技金融政策与企业大数据应用之间的关系;历史业绩期望落差扩大时,组织处于不明显的“损失”状态,内部的战略调整动机相对不足.因此,应继续深化改革,推动科技金融政策不断延伸和拓展.同时,在政策推行过程中,企业应进一步完善公司治理结构,充分发挥针对业绩期望落差的内部响应机制.

关键词：科技金融大数据应用业绩预期差距

An LMI-based variable structure control for a classof uncertain singular Markov switched systems

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控制理论与应用（英文版） 2007年第4期5卷 415-419页

作者： Lijun gao yuqiang WU Institute of Automation Qufu Normal University Rizhao Shandong 276826 China

An H-infinifty variable structure control is presented for singular Markov switched systems with mismatched norm-bounded uncertainties and mismatched norm-bounded external disturbances. It is shown that the sliding mode dynamics on the given switching surface is regular, impulse-free, and stochastically stable and satisfies H-infinity performance. A variable structure controller is designed to guarantee that the system trajectory converges to the linear switching surface in some finite time. Finally, a numerical example is solved to show the effectiveness and validness of the theoretical results.

关键词： Markov switched systems Variable structure LMI Switching surface

Association between NAFLD and Risk of Colorectal Adenoma in Chinese Han Population

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Journal of Clinical and Translational Hepatology 2019年第2期7卷 99-105页

作者： Yuan Li Shousheng Liu yuqiang gao Huan Ma Shuhui Zhan Yan Yang Yongning Xin Shiying Xuan Department of Gastroenterology Qingdao Municipal HospitalQingdaoChina Department of Infectious Disease Qingdao Municipal HospitalQingdaoChina Central Laboratories Qingdao Municipal HospitalQingdaoChina Digestive Disease Key Laboratory of Qingdao QingdaoChina

Background and Aims:Colorectal cancer is associated with non-alcoholic fatty liver disease(NAFLD)and other metabolic syndromes,such as obesity,abnormal blood glucose,and *** relationship of NAFLD and colorectal adenoma,which is the precursor of colorectal cancer,is worthy of *** aim of this study was to investigate the association between colorectal adenoma and NAFLD,colorectal adenoma and metabolic syndrome in a Chinese Han ***:This retrospective study analyzed the relationship between NAFLD and colorectal adenoma in 1089 patients in Qingdao municipal *** were divided into a colorectal adenoma group(n=267)and a control group(n=822).NAFLD and the controlled attenuation parameter(CAP)value were determined by abdominal ultrasound and ***:Patients with NAFLD in the colorectal adenoma group and the control group represented 142 cases(53.2%)and 360 cases(43.8%),*** mean CAP value in the colorectal adenoma group was significantly higher than that in the control *** values of body mass index,triglyceride,high-density lipoprotein cholesterol,aspartate aminotransferase,fasting plasma glucose,and uric acid were also significantly higher in the colorectal adenoma group than in the control *** logistic regression analysis showed that the sex,NAFLD,CAP,body mass index,triglyceride,aspartate aminotransferase,and fasting plasma glucose were significant risk factors for colorectal ***,NAFLD and CAP value were significant risk factors for colorectal adenoma in males but not in ***:NAFLD and metabolic syndrome were tightly associated with the risk of colorectal adenoma in this Chinese Han *** effect of NAFLD on colorectal adenoma was prominent in males rather than in females.

关键词： Non-alcoholic fatty liver disease(NAFLD) Colorectal adenoma Metabolic syndrome Controlled attenuation parameter(CAP)

Unlocking efficient energy storage via regulating ion and electron-active subunits:an(SbS)_(1.15)TiS_(2)superlattice for large and fast Na^(+)storage

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Science China Chemistry 2024年第1期67卷 336-342页

作者： Baixin Peng Tianxun Cai Shaoning Zhang yuqiang Fang Zhuoran Lv Yusha gao Fuqiang Huang State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Physical Science and Technology ShanghaiTech UniversityShanghai 200031China Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Alloying-type metal sulfides with high sodiation activity and theoretical capacity are promising anode materials for high energy density sodium ion ***,the large volume change and the migratory and aggregation behavior of metal atoms will cause severe capacity decay during the charge/discharge ***,a robust and conductive TiS_(2)framework is integrated with a high-capacity SbS layer to construct a single phase(SbS)_(1.15)TiS_(2)superlattice for both high-capacity and fast Na^(+)*** metallic TiS_(2)sublayer with high electron activity acts as a robust and conductive skeleton to buffer the volume expansion caused by conversion and alloying reaction between Na+and SbS ***,high capacity and high rate capability can be synergistically realized in a single phase(SbS)_(1.15)TiS_(2)*** novel(SbS)_(1.15)TiS_(2)anode has a high charge capacity of 618 mAh g^(-1)at 0.2 C and superior rate performance and cycling stability(205 mAh g^(-1)at 35 C after 2,000 cycles).Furthermore,in situ and ex situ characterizations are applied to get an insight into the multi-step reaction *** integrity of robust Na-Ti-S skeleton during(dis)charge process can be *** superlattice construction idea to integrate the Na^(+)-active unit and electron-active unit would provide a new avenue for exploring high-performance anode materials for advanced sodium-ion batteries.

关键词： (SbS)_(1.15)TiS_(2) sulfides sodium ion battery superlattice fast-charging

代谢相关标志物用于良性前列腺增生的临床价值研究

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临床医学研究与实践 2024年第19期9卷 21-24页

作者：姜家利陈维霞张义高玉强刘晶张芬枣庄市立医院山东枣庄277102

目的通过检测老年良性前列腺增生(BPH)患者的糖脂代谢相关指标,评价其与BPH的相关性,探讨将糖脂代谢相关指标纳入BPH常规检测的可能性,进一步对老年BPH患者治疗提出指导性建议。方法选取2021年7月至2022年6月于枣庄市立医院就诊的85例BP... 详细信息

目的通过检测老年良性前列腺增生(BPH)患者的糖脂代谢相关指标,评价其与BPH的相关性,探讨将糖脂代谢相关指标纳入BPH常规检测的可能性,进一步对老年BPH患者治疗提出指导性建议。方法选取2021年7月至2022年6月于枣庄市立医院就诊的85例BPH患者设为BPH组,同期于本院体检的54例健康人员设为健康对照组。检测两组研究对象的糖化白蛋白(GA)、血清白蛋白(ALB)、总胆汁酸(TBA)、1,5-脱水-D-山梨醇(1,5-AG)以及丙酮酸(PYR)和糖化血红蛋白(HbA1c)水平。采用Pearson分析探讨BPH与各指标间的相关性,绘制受试者工作特征(ROC)曲线,以曲线下面积(AUC)评价相关指标对BPH的诊断价值。结果BPH组的BMI显著高于健康对照组(P<0.001)。BPH组的ALB、1,5-AG水平显著低于健康对照组,HbA1c显著高于健康对照组(P<0.01)。BMI、HbA1c与BPH发生呈正相关,ALB和1,5-AG与BPH发生呈负相关(P<0.05)。ALB、1,5-AG和HbA1c诊断BPH的AUC分别为0.796、0.701和0.656。结论ALB、1,5-AG水平降低以及HbA1c升高是BPH患者疾病进展的危险因素,建议将糖脂代谢相关指标ALB、1,5-AG和HbA1c纳入BPH常规检测。

关键词：良性前列腺增生糖化白蛋白血清白蛋白总胆汁酸 1,5-脱水-D-山梨醇丙酮酸糖化血红蛋白

Effect of rainfall interannual variability on the biomass and soil water distribution in a semiarid shrub community

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Science China(Life Sciences) 2010年第6期53卷 729-737页

作者： LIU JunShanXU XiaZHANG Yong,TIAN yuqiang & gao Qiong State Key Laboratory of Earth Surface Processes and Resource Ecology,College of Resources Science & Technology,Beijing Normal University,Beijing 100875,China State Key Laboratory of Earth Surface Processes and Resource Ecology College of Resources Science & Technology Beijing Normal University Beijing China

The dynamics of biomass and soil moisture in semiarid land is driven by both the current rainfall and the ecosystem *** on a meta-analysis of existing experiments,an ecosystem model was used to calculate the effect of the rainfall interannual variability on the pattern of biomass and soil moisture in a shrub *** was found that rainfall interannual variability enabled shrubs to be more competitive than grasses,and to maintain the dominant role over a longer *** rainfall interannual variability resulted in complex soil moisture *** soil water recharge in wet years alternated with discharge in drought years.

关键词： rainfall shrub community Artemisia ordosica ecosystem model ecohydrology