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基于语音信号时频特征融合的帕金森病检测方法

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郑州大学学报（理学版） 2025年第1期57卷 53-60页

作者：王晨哲季薇郑慧芬李云南京邮电大学计算机学院江苏南京210023 南京邮电大学通信与信息工程学院江苏南京210003 南京医科大学附属老年医院江苏南京210009

发音障碍是帕金森病的早期症状之一。近年来,基于语音信号的帕金森病检测的研究大多采用梅尔刻度下的相关语音特征与深度神经网络模型相结合的方法。然而,现有的模型无法充分关注语音信号的全局时序信息,且梅尔刻度特征在准确表征帕金... 详细信息

发音障碍是帕金森病的早期症状之一。近年来,基于语音信号的帕金森病检测的研究大多采用梅尔刻度下的相关语音特征与深度神经网络模型相结合的方法。然而,现有的模型无法充分关注语音信号的全局时序信息,且梅尔刻度特征在准确表征帕金森病的病理信息方面效果有限。为此,提出了一种基于语音时频特征融合的帕金森病检测方法。首先,提取语音的梅尔频率倒谱系数,并将其作为模型的输入。接着,在已有的S-vectors模型中引入Conformer编码器模块,以提取语音的时域全局特征。最后,将与帕金森病语音检测相关的频域全局特征嵌入时域特征中进行时频信息融合,以实现帕金森病语音检测。在公开帕金森病语音数据集和自采语音数据集上验证了方法的有效性。

关键词：帕金森病梅尔频率倒谱系数 S-vectors Conformer 时频特征融合

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Enhanced cooperative packet retransmission employing joint cooperative diversity and symbol mapping diversity

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第8期9卷 1090-1098页

作者： wei ji Bao-yu ZHENG Electronic Engineering Department Shanghai Jiao Tong University Shanghai 200240 China Institute qf Signal Processing and Transmission Nanjing University of Posts ＆ Telecommunications Nanjing 210003 China

A joint cooperation diversity and symbol mapping diversity (SMD) strategy is proposed for cooperative packet retransmission system with high-order modulation such as 16QAM. Substantial SER/BER (symbol error rate/bit error rate) gains result from multiple packet transmissions over independent paths and distinct bit-to-symbol mappings for each packet transmis-sion. The SER/BER performance of relay assisted retransmission system is analyzed. Simulation results show that the joint-diversity strategy can provide more BER gains than other relaying strategies (i.e., decode-and-forward and constellation rearrangement relaying strategies) when no relay makes a decision error; but if some relays make decision errors, the joint-di-versity strategy outperforms other relaying strategies only when the relays are closer to the source than to the destination.

关键词： Cooperative retransmission Hybrid automatic repeat request (HARQ) Cooperative diversity Symbol mapping diversity (SMD)

Flashover in Back-Triggered Photoconductive Semiconductor Switch

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Chinese Physics Letters 2011年第1期28卷 106-108页

作者： SHI wei jiA ji-Qiang ji wei-Li GUI Huai-Meng Applied Physics Department Xi'an University of Technology Xi'an 710048 State Key Laboratory of Electrical Insulation for Power Equipment Xi'an Jiaotong University Xi'an 710049

Design of a new type of photoconductive semiconductor switches （PCSSs） is presented, and the withstand voltage is improved. The ttashover voltage of the back-triggered PCSS is found to be higher than that of the front-triggered one. By analyzing the differences of the flashover voltage between the back-triggered PCSS and the front-triggered PCSS, a detailed statistics analysis and theoretical explanation are expounded. The experiments also prove that the PCSS we developed could resist a voltage as high as 20 k V under the repetition frequency of 30 Hz.

关键词： Electronics and devices Optics, quantum optics and lasers

Local resonance phononic band gaps in modifiedtwo-dimensional lattice materials

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Acta Mechanica Sinica 2012年第3期28卷 659-669页

作者： wei Liu ji-wei Chen Xian-Yue Su LTCS and Department of Mechanics and Aerospace Engineering College of EngineeringPeking University100871 BeijingChina

In this paper, modified two-dimensional peri- odic lattice materials with local resonance phononic band gaps are designed and investigated. The design concept is to introduce some auxiliary structures into conventional pe- riodic lattice materials. Elastic wave propagation in this kind of modified two-dimensional lattice materials is studied us- ing a combination of Bloch＇s theorem with finite element method. The calculated frequency band structures of illus- trative modified square lattice materials reveal the existence of frequency band gaps in the low frequency region due to the introduction of the auxiliary structures. The mechanism underlying the occurrence of these frequency band gaps is thoroughly discussed and natural resonances of the auxiliary structures are validated to be the origin. The effect of geo- metric parameters of the auxiliary structures on the width of the local resonance phononic band gaps is explored. Finally, a conceptual broadband vibration-insulating structure based on the modified lattice materials is designed and its capabil- ity is demonstrated. The present work is anticipated to be useful in designing structures which can insulate mechanical vibrations within desired frequency ranges.

关键词： Modified lattice materials Bloch's theoremLocal resonance phononic band gaps Vibration insulation

不同强度运动抑制糖尿病大鼠肾脏PI3K/AKT/mTOR信号通路改善自噬的比较

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中国组织工程研究 2025年第11期29卷 2310-2318页

作者：周鸿雁张译丹季威刘霞湖南文理学院体育学院湖南省常德市415000 湖南师范大学体育学院体适能与运动康复湖南省重点实验室湖南省长沙市410012

背景:2型糖尿病损害肾功能。研究表明运动干预可以保护肾脏;鸢尾素可以通过抑制磷脂酰肌醇3-激酶/蛋白激酶B/雷帕霉素靶蛋白信号通路恢复自噬,保护糖尿病肾病患者的肾功能。目的:探讨运动能否通过抑制肾脏磷脂酰肌醇3-激酶/蛋白激酶B/... 详细信息

背景:2型糖尿病损害肾功能。研究表明运动干预可以保护肾脏;鸢尾素可以通过抑制磷脂酰肌醇3-激酶/蛋白激酶B/雷帕霉素靶蛋白信号通路恢复自噬,保护糖尿病肾病患者的肾功能。目的:探讨运动能否通过抑制肾脏磷脂酰肌醇3-激酶/蛋白激酶B/雷帕霉素靶蛋白信号通路过度激活来恢复自噬,改善肾损伤,以及分析不同方式运动产生影响的差异。方法:将6周龄的SD大鼠随机分为空白对照组(正常大鼠)和糖尿病组,其中糖尿病组大鼠经过高脂高糖喂养加腹腔注射低剂量1%链脲佐菌素(30 mg/kg)建立2型糖尿病模型。造模成功后再将糖尿病组大鼠随机分成糖尿病模型组、中强度持续运动组和高强度间歇运动组。两个运动组大鼠分别进行8周不同强度运动干预。取材后采用葡萄糖氧化酶法检测大鼠空腹血糖,使用试剂盒检测糖化血红蛋白水平,Elisa法检测血清胰岛素浓度,计算胰岛素抵抗指数,RT-PCR检测肾组织磷脂酰肌醇3-激酶、蛋白激酶B、雷帕霉素靶蛋白、Beclin-1、podocin、nephrin的基因表达量,Western Blot检测肾组织雷帕霉素靶蛋白及自噬标记蛋白LC3-1、LC3-2、Beclin-1的蛋白表达量。结果与结论:①2型糖尿病大鼠空腹血糖和糖化血红蛋白水平极显著性升高,胰岛素抵抗水平显著上升,胰岛素水平显著下降;两种运动均能使2型糖尿病大鼠空腹血糖和糖化血红蛋白水平极显著下降,胰岛素抵抗水平显著下降,胰岛素水平显著上升;与中强度持续运动组相比,高强度间歇运动组胰岛素水平显著上升。②2型糖尿病大鼠podocin、nephrin基因表达量显著降低;两种不同形式运动均能显著提高其表达;与高强度间歇运动组相比,中等强度持续性运动组足细胞相关蛋白基因表达有进一步上升趋势,但无显著性差异。③2型糖尿病大鼠肾组织磷脂酰肌醇3-激酶、蛋白激酶B、mTORC1的mRNA及蛋白的表达量显著增加,自噬标志蛋白Beclin-1、LC3-2表达量以及LC3-2/LC3-1显著降低;两种不同形式运动均能使肾组织磷脂酰肌醇3-激酶、蛋白激酶B、mTORC1的mRNA及雷帕霉素靶蛋白蛋白的表达量显著降低,自噬标志蛋白Beclin-1、LC3-2以及LC3-2/LC3-1显著升高;与中等强度持续性运动组相比,高强度间歇运动的磷脂酰肌醇3-激酶、蛋白激酶B、mTORC1的mRNA及雷帕霉素靶蛋白的蛋白表达量有进一步下降的趋势,Beclin-1、LC3-2以及LC3-2/LC3-1有进一步升高的趋势,但仅Beclin-1有显著性差异。④结果说明2型糖尿病肾脏足细胞损伤,自噬受到抑制,与磷脂酰肌醇3-激酶/蛋白激酶B/mTORC1信号通路被异常激活密切相关。高强度间歇运动和中等强度持续性运动可以保护糖尿病肾脏,减少足细胞损伤,促进自噬恢复,这可能与运动抑制磷脂酰肌醇3-激酶/蛋白激酶B/雷帕霉素靶蛋白信号通路过度激活有关。与中等强度持续性运动相比,高强度间歇运动恢复自噬的效果呈更优趋势,但足细胞蛋白表达稍有下降。

关键词：糖尿病肾病足细胞自噬高强度间歇运动中等强度持续性运动 PI3K AKT mTOR

Effect of Ultra-low Temperature on Carbonation Performance of SFRRC and Prediction Model

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Journal of Wuhan University of Technology(Materials Science) 2023年第4期38卷 778-788页

作者：钱维民苏骏 ZHAO jiayu ji wei School of Civil Engineering and Environment Hubei University of TechnologyWuhan430068China College of Engineering and Technology Hubei University of TechnologyWuhan430068China

Through the rapid carbonation test of SFRRC with different fiber volume fractions at ultralow temperature,the influence of ultra-low temperature damage on the carbonation resistance of SFRRC was analyzed,which provides a theoretical basis for the application of SFRRC in ultra-low temperature *** experimental results show that ultra-low temperatures can significantly weaken the carbonization resistance of *** the temperature reaches 160℃,the carbonization depth increases by 67.66%compared with the normal *** proper amount of steel fiber has an evident influence on the carbonation resistance of the ***,when the addition amount exceeds the optimum content,the carbonation resistance of the material *** grey prediction model established by constructing the original sequence can reasonably predict the carbonation resistance of SFRRC after ultra-low temperatures.

关键词： ultra-low temperature SFRRC carbonization grey model

Impurity effects of theΛhyperon in the hypernuclear systems^(25)ΛMg and(29)ΛSi

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Communications in Theoretical Physics 2021年第11期73卷 116-121页

作者： ji-wei Cui Xian-Rong Zhou School of Physics and Optoelectronic Engineering Xidian UniversityXi'an 710071China Department of Physics East China Normal UniversityShanghai 200241China

Based on the beyond-mean-field Skyrme-Hartree-Fock model,impurity effects of theΛhyperon in the hypernuclear systems^(25)ΛMg and^(29)ΛSi are investigated,*** cases,in which theΛhyperon occupies the single-particle orbitals L[000]1+/2,L[110]1-/2,L[101]3-/2 and L[101]1-/2,are *** each case,the potential energy surface and the energy curves projected on certain angular momenta are employed to show the influence of theΛhyperon on the nuclear *** the shrinkage effect that is induced by theΛhyperon occupying the sΛorbital,it is found that theΛhyperon on the pΛorbital,L[110]1-/2,drives the nuclear core toward a prolate shape,while the ones on the other two pΛorbitals,L[101]3-/2 and L[101]1-/2,drive the nuclear core toward an oblate *** energy spectra and the corresponding intra-band E2 transition rates for the rotational bands are given as a prediction for future experiments.

关键词： Λhypernuclei Skyrme-Hartree-Fock model angular momentum projection generator coordinate method

The Stellar Spectra Factory(SSF)Based on SLAM

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Research in Astronomy and Astrophysics 2023年第5期23卷 148-159页

作者： wei ji Chao Liu Bo Zhang Key Laboratory of Space Astronomy and Technology National Astronomical ObservatoriesCASBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Institute for Frontier in Astronomy and Astrophysics Beijing Normal UniversityBeijing 100875China

An empirical stellar spectral library with large coverage of stellar parameters is essential for stellar population synthesis and studies of stellar *** this work,we present Stellar Spectra Factory(SSF),a tool to generate empirical-based stellar spectra from arbitrary stellar atmospheric *** relative flux-calibrated empirical spectra can be predicted by SSF given arbitrary effective temperature,surface gravity,and *** constructs the interpolation approach based on the Stellar LAbel Machine,using ATLAS-A library,which contains spectra covering from O type to M type,as the training data *** is composed of four data-driven sub-models to predict empirical stellar ***-model SSF-N can generate spectra from A to K type and some M giant stars,covering 3700

关键词： methods statistical-techniques spectroscopic-stars atmospheres-stars general

Numerical simulation of coupling heat transfer and thermal stress for spent fuel dry storage cask with different power distribution and tilt angles

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Nuclear Science and Techniques 2023年第2期34卷 109-127页

作者： wei‑Hao ji jian‑jie Cheng Han‑Zhong Tao wei Li College of Urban Construction Nanjing Tech UniversityNanjing 211800China School of Energy Science and Engineering Nanjing Tech UniversityNanjing 211800China

Dry storage containers must be secured and reliable during long-term storage,and the effect of decay heat released from the internal spent fuel on the cask has become an important research *** this paper,a 3D computational fluid dynamics model is presented,and the accuracy of the calculation is verified,with computational errors of less than 6.2%.The thermal stress of the dry storage cask was estimated by coupling it with a transient temperature *** total power remained constant and adjusting the power ratio of the inner and outer zones had a small effect on the stress results,with a maximum equivalent stress of approximately 5.2 kPa,which occurred at the lower edge of the *** the case of tilt,the temperature gradient varied in a wavy distribution,and the wave crest moved from right to *** the tilt angle affects the air distribution in the annular gap,leading to the shell temperature being transformed,with a maximum equivalent stress of 202 MPa at the bottom of the ***,the equivalent stress in both cases was less than the yield stress(205 MPa).

关键词： Thermal stress CFD simulation Spent nuclear fuel Dry storage cask