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音乐训练经验与节奏变化空间表征的关系:基于SMARC效应的检验

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应用心理学 2024年第1期30卷 77-85页

作者：陈睿陈玉田李鹏张舒琦陈麒伊云南师范大学教育学部昆明650500

运用眼动分析法,采用架子鼓渐快/渐慢节奏听觉材料,利用SMARC效应的机制,探讨个体的音乐训练经验与其形成节奏变化的空间表征的关系。结果显示,相对于无音乐训练经验被试,有音乐训练经验被试在渐快节奏下对远方位有更多注视时间,在渐慢... 详细信息

运用眼动分析法,采用架子鼓渐快/渐慢节奏听觉材料,利用SMARC效应的机制,探讨个体的音乐训练经验与其形成节奏变化的空间表征的关系。结果显示,相对于无音乐训练经验被试,有音乐训练经验被试在渐快节奏下对远方位有更多注视时间,在渐慢节奏下对近方位有更多注视时间。即在有音乐训练经验者身上更可能观察到音乐节奏变化与远近空间方位的SMARC效应。因此,个体能否形成音乐节奏变化的空间表征与其音乐训练经验存在关系。

关键词： SMARC效应音乐训练经验眼动

面向广义Chiplet的高速BGA与PCB传输结构设计

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计算机工程与科学 2024年第6期46卷 977-983页

作者：陈天宇李川王彦辉江南计算技术研究所江苏无锡214083

从广义Chiplet互连设计出发,重点研究BGA区域孔串扰分析方法和优化措施。提出以单元阵列孔建模计算作为全芯片BGA区域孔串扰评估方式,进一步根据不同布线层互连分析需求构建了多层扇出的孔建模平台。单元阵列孔建模分析结果和多层扇出... 详细信息

从广义Chiplet互连设计出发,重点研究BGA区域孔串扰分析方法和优化措施。提出以单元阵列孔建模计算作为全芯片BGA区域孔串扰评估方式,进一步根据不同布线层互连分析需求构建了多层扇出的孔建模平台。单元阵列孔建模分析结果和多层扇出孔阵建模分析结果相互印证,说明以单元阵列作为串扰评估最小单元是准确的,多层扇出孔阵建模方式是高效可行的。采用多层扇出孔阵建模平台对2种BGA封装管脚对应的PCB孔串扰进行了对比分析。结果显示,在封装管脚设计时,提高邻近信号孔间距与邻近信号孔地孔间距比例比增加地孔数量和管脚间距更能有效地抑制串扰。

关键词：单元阵列球栅阵列管脚分配孔信号完整性串扰

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基于端部漏磁场分析的集成式电机驱动系统在线匝间短路故障诊断

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科学技术与工程 2024年第27期24卷 11693-11702页

作者：柴琳周菁陈天宇刘毅刘志伟武汉科技大学信息科学与工程学院武汉430081 华中科技大学电气与电子工程学院武汉430074

基于宽禁带器件的变频器具有高功率密度和耐高温工作的优势,通过小型化和轻薄化设计可以将变频器置于电机端盖与端绕组之间,构成结构紧凑的集成式电机驱动系统。该系统发生匝间短路故障时,短路绕组电流增大不仅会使电机内部温度升高导... 详细信息

基于宽禁带器件的变频器具有高功率密度和耐高温工作的优势,通过小型化和轻薄化设计可以将变频器置于电机端盖与端绕组之间,构成结构紧凑的集成式电机驱动系统。该系统发生匝间短路故障时,短路绕组电流增大不仅会使电机内部温度升高导致电机绝缘性能降低,还将引起磁场变化影响变频器的正常工作。以一台1.5 kW的交流感应电机为例,搭建基于宽禁带器件的集成式电机驱动系统三维物理模型,利用数学解析法分析并计算匝间短路故障前后的端部漏磁场,并提取电机内端部印制电路板(printed circuit board,PCB)表面与轴心距离相等、机械角度相差45°的两点处磁感应强度在直角坐标系下椭圆曲线的离心率反映端部漏磁场的对称性,以此为特征指标判断电机是否出现匝间短路故障。仿真与实验结果验证了所提方法的正确性和有效性。

关键词：集成式电机驱动系统匝间短路故障端部漏磁场有限元分析

Resveratrol, an activator of SIRT1, restores erectile function in streptozotocin-induced diabetic rats

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Asian Journal of Andrology 2013年第5期15卷 646-651页

作者： Wen yu Zan Wan Xue-Feng Qiu yun chen yu-tian Dai Department of Urology Affiliated Drum Tower Hospital School of Medicine Nanjing University Nanjing 210008 China

The high incidence of erectile dysfunction （ED） in diabetes highlights a need for effective treatment strategies. Resveratrol, an activator of silent information regulator 2-related enzymes 1 （sirtuinl, SIRT1）, has received attention for its valuable effects in cancer, neurodegenerative diseases, longevity and cardiovascular disease. To explore the effects of resveratrol in diabetes-induced ED, resveratrol was administered to rats with streptozocin （65 mg kg-1）-induced diabetes. Erectile function, cavernous structure, tissue protein expression of silent information regulator 2-related enzymes 1 （sirtuinl, SIRT1）, p53 and forkhead transcription factor 0 3a （FOXO3a）, superoxide dismutase （SOD） activity and malondialdehyde （MDA） levels in the corpora cavernosa were studied. We found that SIRT1 was expressed in cavernosal tissue, and it was downregulated in the corpora of diabetic rats. The administration of resveratrol upregulated the expression of SI RT1 and restored erectile function. In contrast, resveratrol downregulated the expression of p53 and FOXO3a, which regulate apoptosis and oxidative stress. Furthermore, the resveratrol-treated group showed an improvement in smooth muscle content, SOD activity and MDA levels when compared with the diabetic group. Therefore, the ability of resveratrol to improve diabetes-induced ED is likely related to its activation of SIRT1 expression, thus causing the suppression of apoptosis and resistance towards oxidative stress.

关键词： apoptosis erectile dysfunction oxidative stress resveratrol

Tunable plasmon-induced transparency based on asymmetric H-shaped graphene metamaterials

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Chinese Physics B 2018年第12期27卷 297-303页

作者： yu-chen tian Wei Jia Pei-Wen Ren Chun-Zhen Fan School of Physical Science and Engineering Zhengzhou University

We propose and numerically demonstrate a tunable plasmon-induced transparency(PIT) phenomenon based on asymmetric H-shaped graphene metamaterials. The tunable PIT effect is realized through varying the applied polarization angles rather than changing the structure geometry. By simply adjusting the polarization angle, the transmission spectra can be controlled between the switch-on state and switch-off state. The physical mechanism of the induced transparency is revealed from magnetic dipole inductive coupling and phase coupling. Importantly, by varying the Fermi energy of the graphene or the refractive index of the substrate, the resonant position of the PIT can be dynamically controlled and the maximum modulation depths can reach up to 60.7%. The sensitivity(nm/RIU) of the graphene structure, which is the shift of resonance wavelength per unit change of refractive index, is 5619.56 nm/RIU. Moreover, we also extend our research to the x-axis symmetric H-shaped structure, and the tunable PIT transmission window can also be realized. The physical mechanism of the induced transparency is revealed from the electric dipole hybridization coupling. Our designed H-shaped graphene-based structures is a promising candidate for compact elements such as tunable sensors, switches and slow-light devices.

关键词： plasmon-induced transparency graphene polarization optical filter

Dynamically tunable optical properties in graphene-based plasmon-induced transparency metamaterials

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Chinese Physics B 2019年第2期28卷 363-368页

作者： Wei Jia Pei-Wen Ren yu-chen tian Chun-Zhen Fan School of Physical Science and Engineering Zhengzhou University

A graphene-based metamaterial for THz plasmon induced transparency(PIT) is presented and numerically studied in this paper, which consists of two horizontal graphene strips attached to a continuous vertical wire separately. The calculated surface current distributions demonstrate that the distinct PIT window results from the near-field coupling of two bright modes. To explore the physical mechanism of PIT effect, we employ the coupled Lorentz oscillator model. The transmission spectra obtained with this model fits well with the simulation results. The performance of the PIT system can be controlled through the geometry parameters of graphene strips. Moreover, the transparency window can be dynamically tuned by varying the Fermi energy and the carrier mobility of the graphene strips. The slow light effect is also explored in our proposed structure and it can achieve 1.25 ps when Fermi energy is 1.3 eV. Finally, the position of the transmission window with the variation of the nearby medium refractive index is examined. Such a proposed graphene-based PIT system may have great potential applications in photonic devices.

关键词： plasmon-induced transparency graphene tunable

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用于Buck变换器的精确电流控制技术

电力电子技术 2024年第8期58卷 96-98页

作者：余锦俊陈天宇陆江华佃仁俊武汉科技大学信息科学与工程学院湖北武汉430081

Buck变换器广泛运用在电压调节模块、负载点电源、LED电源模块等电力电子设备中,用来实现电压的转化,其工作模式可分为连续导通模式(CCM)、断续导通模式(DCM)和临界导通模式(CRM)。传统的变换器构建了闭环控制回路对自身进行反馈控制,使... 详细信息

Buck变换器广泛运用在电压调节模块、负载点电源、LED电源模块等电力电子设备中,用来实现电压的转化,其工作模式可分为连续导通模式(CCM)、断续导通模式(DCM)和临界导通模式(CRM)。传统的变换器构建了闭环控制回路对自身进行反馈控制,使Buck变换器具有良好的输出能力。为了更精确地调节变换器的输出,此处提出了一种DCM下的Buck变换器精确电流控制技术,利用DCM下每个周期电感电流下降至零的特点,构建了电感电流精确控制算法。该控制算法针对非同步Buck变换器,通过控制功率管开通的时间,实现精确的电流控制技术,进而取得更为良好的静动态性能。基于理论研究方法,以宽禁带功率器件为基础,设计了一台功率为500 W的原型机,用于验证所提算法的可行性。

关键词：变换器精确电流控制断续导通模式

Evaluation and attribution of trends in compound dry-hot events for major river basins in China

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Science China Earth Sciences 2024年第1期67卷 79-91页

作者： Shaotang XIONG Tongtiegang ZHAO chengchao GUO yu tian Fang YANG Wenlong chen Xiaohong chen Key Laboratory of Water Security Guarantee in Guangdong-Hong Kong-Marco Greater Bay Area of Ministry of Water Resources&Sun Yatsen University/Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Guangzhou 510275China China Institute of Water Resource and Hydropower Research Beijing 100038China Pearl River Hydraulic Research Institute Guangzhou 510611China

Concurrent compound dry and hot events(CDHEs)amplified more damange on the ecosystems and human society than individual *** climate change,compound dry and hot events become more frequent on a global *** paper proposes a mathematical method to quantitatively attribute changes of CDHEs to changes of precipitation,change in temperature and change in the dependence between precipitation and *** attribution is achieved by formulating the total differential equation of the return period of CDHEs among Meta-gaussian model.A case study of China is devised based on monthly precipitation and temperature data during the period from 1921 to 2020 for 80 major river *** is found that temperature is the main driving factor of increases in CDHEs for 49 major river basins in China,except for the upper and middle reaches of the Yangtze *** West China,precipitation changes drove the increase in CDHEs in 18 river basins(23%),particularly in parts of North Xinjiang,Qinghai and *** the other hand,dependence between precipitation and temperature dominated changes of CDHEs in 13 river basins(16%)of China with other factors,including parts of South China,East China and Northwestern ***,changes in both the mean and spread of precipitation and temperature can also contribute to changes in CDHEs.

关键词： Climate extreme Compound dry and hot extreme Precipitation Temperature Return period

Soil disturbance evaluation of soft clay based on stress-normalized smallstrain stiffness

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 990-999页

作者： Yanguo Zhou yu tian Junneng Ye Xuecheng Bian yunmin chen MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Institute of Geotechnical EngineeringCenter for Hypergravity Experiment and Interdisciplinary ResearchZhejiang UniversityHangzhou310058China Ningbo Rail Transit Group Co. Ltd.Ningbo315010China

Soil disturbance includes the change of stress state and the damage of soil *** field testing indices reflect the combined effect of both changes and it is difficult to identify the soil structure disturbance directly from these *** the present study,the small-strain shear modulus is used to characterize soil structure disturbance by normalizing the effective stress and void ratio based on Hardin *** procedure for evaluating soil sampling disturbance in the field and the further disturbance during the subsequent consolidation process in laboratory test is proposed,and then validated by a case study of soft clay *** seismic testing in the field,portable piezoelectric bender elements for the drilled sample and bender elements in triaxial apparatus for the consolidated sample were used to monitor the shear wave velocity of the soil from intact to disturbed and even remolded *** is found that soil sampling disturbance degree by conventional thin-wall sampler is about 30%according to the proposed procedure,which is slightly higher than that from the modified volume compression method proposed by Hong and Onitsuka(1998).And the additional soil disturbance induced by consolidation in laboratory could reach about 50%when the consolidation pressure is far beyond the structural yield stress,and it follows the plastic volumetric strain quite well.

关键词： Natural clay Soil sample disturbance Shear wave velocity Small-strain shear modulus Hardin equation