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Chinese Journal of Acoustics 2002年第4期21卷 317-324页

作者： CHEN Xi WANG Yuanyuan zhang Yu WANG Weiqi (department of electronic engineering, fudan university shanghai 200433)Received Jun. 11, 2001 Revised Jul. 4, 2001 department of electronic engineering Fudan University Shanghai200433

In order to diagnose the cerebral infarction, a classification system based on the ARMA model and BP (Back-Propagation) neural network is presented to analyze blood flow Doppler signals from the carotid artery. In this system, an ARMA model is first used to analyze the audio Doppler blood flow signals from the carotid artery. Then several characteristic parameters of the pole’s distribution are estimated. After studies of these characteristic parameters’ sensitivity to the textcolor cerebral infarction diagnosis, a BP neural network using sensitive parameters is established to classify the normal or abnormal state of the cerebral vessel. With 474 cases used to establish the appropriate neural network, and 52 cases used to test the network, the results show that the correct classification rate of both training and testing are over 94%. Thus this system is useful to diagnose the cerebral infarction.

关键词： ARMA In The ARMA model s pole characteristics of Doppler signals fromthe carotid artery and their classification application

Anisotropic phonon dynamics in Dirac semimetal PtTe2 thin films enabled by helicity-dependent ultrafast light excitation

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Light(Science & Applications) 2024年第9期13卷 1888-1897页

作者： Ziyang Li Yequan Chen Anke Song Jinzhong zhang Rong zhang Zongzhi zhang Xuefeng Wang Key Laboratory of Micro and Nano Photonic Structures(MOE) School of Information Science and TechnologyFudan UniversityShanghaiChina Jiangsu Provincial Key Laboratory of Advanced Photonic and electronic Materials State Key Laboratory of Spintronics Devices and TechnologiesSchool of Electronic Science and EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjingChina department of Physics School of Physics and Electronic ScienceEast China Normal UniversityShanghaiChina department of Physics Xiamen UniversityXiamenChina

Coherent phonons have aroused considerable attention in condensed matter physics owing to their extraordinary capacity of reflecting and controlling the physical properties of ***,the investigation on the interaction between coherent phonons and other microscopic particles on the ultrafast timescale within topological systems continues to be an active and unresolved ***,we show the energy transfer of coherent optical phonons(COP)in Dirac semimetal PtTe2 thin films using ultrafast optical pump-probe ***,the helicitydependent light-driven anisotropic COP signals disclose their direct connection with the light-excited anisotropic spinpolarized electrons via an angular momentum ***,we observe the notable decreases in the COP oscillation frequency and the decay rate with increasing temperatures due to the anharmonic phonon-phonon scattering and electron-phonon scattering in the COP dissipation process,*** work paves the way for uncovering the coherent phonons in Dirac semimetals for the potential applications in optoelectronics and optospintronics.

关键词： spectroscopy. phonon Dirac

A Weighted Inner Product Estimator in the Geometric Algebra of Euclidean 3-Space for Source Localization Using an EM Vector-sensor

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Chinese Journal of Aeronautics 2012年第1期25卷 83-93页

作者： JIANG Jingfei zhang jianqiu department of electronic engineering Fudan UniversityShanghai 200433China

In this paper, the source localization by utilizing the measurements of a single electromagnetic （EM） vector-sensor is investigated in the framework of the geometric algebra of Euclidean 3-space. In order to describe the orthogonality among the electric and magnetic measurements, two multivectors of the geometric algebra of Euclidean 3-space （G3） are used to model the outputs of a spatially collocated EM vector-sensor. Two estimators for the wave propagation vector estimation are then formulated by the inner product between a vector and a bivector in the G3. Since the information used by the two estimators is different, a weighted inner product estimator is then proposed to fuse the two estimators together in the sense of the minimum mean square error （MMSE）. Analytical results show that the statistical performances of the weighted inner product estimator are always better than its traditional cross product counterpart. The efficacy of the weighted inner product estimator and the correctness of the analytical predictions are demonstrated by simulation results.

关键词： cross product electromagnetic geometric algebra geometric algebra of Euclidean 3-space minimum mean square rule direction finding vector-sensor

Computer simulation of intravascular ultrasound plaque images

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Chinese Journal of Acoustics 2009年第4期28卷 310-321页

作者： zhang Qi WANG Yuanyuan WANG Weiqi MA Jianying QIAN Juying GE Junbo department of electronic engineering Fudan University Shanghai200433 department of Cardiology Zhongshan Hospital of Fudan University Shanghai200032

A method is proposed to simulate intravascular ultrasound （IVUS） images of athero-sclerotic plaques. To accomplish the simulation of static IVUS plaque images, the ringdown and guidewire artifacts are introduced into the polar image-formation model （PIFM）, and the fibrous, lipid and calcific contents are synthesized in plaques respectively. The simulation of sequential IVUS images can be achieved by utilizing characteristics of the pulsatile artery. The results on static images demonstrate that it outperforms the PIFM method by 56.9% in terms of the correlation coefficient （CC）, and 24.3% in terms of the mutual information （MI）. The results on sequential images demonstrate that it outperforms the PIFM method by 51.0% in terms of CC, and 10.3% in terms of MI.

关键词： IVUS Computer simulation of intravascular ultrasound plaque images

The Marginal Rao-Blackwellized Particle Filter for Mixed Linear/Nonlinear State Space Models

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Chinese Journal of Aeronautics 2007年第4期20卷 346-352页

作者： Yin Jianjun zhang jianqiu Mike Klaas department of electronic engineering Fudan University Shanghai 200433 China department of Computer Science University of British Columbia Vancouver V6T1Z4 Canada

In this paper, the marginal Rao-Blackwellized particle filter （MRBPF）, which fuses the Rao-Blackwellized particle filter （RBPF） algorithm and the marginal particle filter （MPF） algorithm, is presented. The state space is divided into linear and non-linear parts, which can be estimated separately by the MPF and the optional Kalman filter. Through simulation in the terrain aided navigation （tan） domain, it is demonstrated that, compared with the RBPF, the root mean square errors （RMSE） and the error variance of the nonlinear state estimations by the proposed MRBPF are respectively reduced by 29% and 96%, while the unique particle count is increased by 80%. It is also found that the MRBPF has better convergence properties, and analysis has shown that the existing RBPF is nothing more than a special case of the MRBPF.

关键词： signal processing marginal Rao-Blackwellized particle filter simulation mixed linear/nonlinear terrain aided navigation

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冠状动脉阻抗系统的建立及其稳定性

复旦学报（医学版） 2004年第4期31卷 331-335页

作者：张良惠葛均波罗忠池汪源源钱菊英蔡迺绳王威琪复旦大学附属中山医院心内科-上海市心血管病研究所上海200032 复旦大学电子工程系上海200433

目的　利用计算机和图像、信号采集设备建立冠状动脉阻抗系统 ,并研究冠状动脉阻抗参数的稳定性。方法　与心电信号同步通过腔内超声导管、多普勒导丝和压力导丝 ,获取随心动周期变化的冠状动脉腔内超声图像、流速和压力信号 ;通过自制... 详细信息

目的　利用计算机和图像、信号采集设备建立冠状动脉阻抗系统 ,并研究冠状动脉阻抗参数的稳定性。方法　与心电信号同步通过腔内超声导管、多普勒导丝和压力导丝 ,获取随心动周期变化的冠状动脉腔内超声图像、流速和压力信号 ;通过自制软件得到随心动周期变化的腔内面积曲线、平均流速曲线、压力曲线和流量 /压力曲线 ;按机电类比方法通过傅立叶变换得到冠脉阻抗参数。采集不同情况下 1 0头小型猪以及 2 1例病人左前降支的基础状态和最大充血状态重复性测量信号分别为 80对。结果　相关分析发现重复性冠脉阻抗参数间有很好的相关性 (P <0 .0 1 ) ;基础状态和充血状态的平均冠脉阻抗和一次谐波冠脉阻抗的决定系数 (r2 )均大于0 .97(P <0 .0 0 1 )。结论　本实验成功建立反映冠脉脉动流阻力的冠脉阻抗系统。

关键词：冠状动脉阻抗系统建立稳定性多普勒压力血管内超声

Suppression of intervalley scattering and enhanced phonon anharmonic interactions in 2D Bi_(2)TeSe_(2):Crystal-field symmetry and band convergence

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Journal of Materiomics 2024年第2期10卷 386-395页

作者： Lei Peng Ao Wu Yujie Xia Haotian zhang Yuting Yang Hezhu Shao Ying Chen Juan zhang Le Shu Heyuan Zhu Yuxiang Zheng Hao zhang School of Information Science and Technology Department of Optical Science and EngineeringFudan UniversityShanghai 200433China College of Electrical and electronic engineering Wenzhou UniversityWenzhou 325035China department of Light Sources and Illuminating engineering Fudan UniversityShanghai 200433China Yiwu Research Institute of fudan university Yiwu 322000China

The electron-phonon(el-ph)and phonon-phonon interactions play a key role in determining electronic and thermal transport properties,respectively,in promising two-dimensional(2D)semiconductor *** this study,we investigated el-ph interactions using Wannier-Fourier interpolation method and renormalized phonon scattering considering finite-temperature effects in Bi_(2)TeSe_(2)*** re-sults show that the optical phonon modes dominate the carrier scattering,where level repulsion induced by crystal field splitting and spin-orbit coupling(SOC)effect effectively suppresses intervalley scattering,leading to high hole ***,the strong anharmonicity in Bi_(2)TeSe_(2)monolayer results in the temperature-dependent softening of its optical phonons,along with a corresponding variation in interatomic force constants(IFCs).As a result,the lattice thermal conductivity is remarkably low and exhibits weak temperature ***,the predicted dimensionless thermoelectric figure of merit exceeds unity in the range of 200-800 K,indicating the potential of Bi_(2)TeSe_(2)monolayer for thermoelectric *** work provides new insights into the elimination of intervalley scat-tering by crystal field splitting and SOC effects,and paves the way for the evaluation of thermoelectric properties of materials with complex scattering mechanisms and strong anharmonicity.

关键词： El-ph interactions Crystal field splitting Spin-orbit coupling Intervalley scattering Renormalized phonon scattering

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网上黄页站点中矢量电子地图的设计与实现

计算机工程 2000年第8期26卷 157-159,161页

作者：倪俊峰俞立峰陆钧高峻张根度上海大学计算机系上海200072 复旦大学计算机系上海200433

网上黄页站点的电子地图是ＧＩＳ技术在实际应用中的一个热点．在分析和比较当前用来实现基于Ｉｎｔｅｒｎｅｔ的电子地图的诸多方案的基础上，指出使用ＡｃｔｉｖｅＸ技术的优点，并以此实现了一个应用于黄页站点的与ＲＤＢＭＳ和ＩＳ... 详细信息

网上黄页站点的电子地图是ＧＩＳ技术在实际应用中的一个热点．在分析和比较当前用来实现基于Ｉｎｔｅｒｎｅｔ的电子地图的诸多方案的基础上，指出使用ＡｃｔｉｖｅＸ技术的优点，并以此实现了一个应用于黄页站点的与ＲＤＢＭＳ和ＩＳＡＰＩＣＧＩ程序交互结合的网上矢量电子地图．

关键词：矢量电子地图网上黄页站点 Internet网 GIS

随机工况下基于改进ANFIS的锂电池容量衰减实时估计

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仪器仪表学报 2024年第5期45卷 218-226页

作者：刘彤宇陆起涌李旦张建秋王开铟复旦大学电子工程系上海200433 复旦大学义乌研究院义乌322001

锂电池容量的衰减会影响其安全性和稳定性,准确的容量估计能够帮助用户进行更好的决策。目前,广泛使用的黑盒数据驱动模型因其不可解释性很难被应用于安全相关的领域中,并且大多方法都基于固定工况进行特征提取,对具有随机性的实际工况... 详细信息

锂电池容量的衰减会影响其安全性和稳定性,准确的容量估计能够帮助用户进行更好的决策。目前,广泛使用的黑盒数据驱动模型因其不可解释性很难被应用于安全相关的领域中,并且大多方法都基于固定工况进行特征提取,对具有随机性的实际工况不具有普适性。因此,本文构建了一种基于随机工况数据的改进自适应模糊神将网络推理系统(ANFIS)。首先分析了容量衰减的影响因素,据此从电池监测数据中提取和筛选健康特征;其次系统内部利用激活机制简化系统结构,并引入衰减系数更好地拟合电池单体特性;然后通过自适应粒子滤波算法优化模糊聚类中心;最后使用NASA随机工况数据集验证了该系统的有效性,其容量估计RMSE为3.73%。与其他方法相比,本文提出的方法结果精度更高且具有一定的可解释性。

关键词：锂电池模糊推理系统容量估计可解释性

A personalized electronic textile for ultrasensitive pressure sensing enabled by biocompatible MXene/ PEDOT:PSS composite

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Carbon Energy 2024年第3期6卷 224-238页

作者： Yahua Li Wentao Cao Zhi Liu Yue zhang Ziyan Chen Xianhong Zheng department of Interventional Radiology The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenanChina School of Textile and Garment Anhui Polytechnic UniversityWuhuAnhuiChina department of Prosthodontics Shanghai Stomatological Hospital and School of StomatologyFudan UniversityShanghaiChina College of Chemistry Chemical Engineering and BiotechnologyDonghua UniversityShanghaiChina

Flexible,breathable,and highly sensitive pressure sensors have increasingly become a focal point of interest due to their pivotal role in healthcare monitoring,advanced electronic skin applications,and disease ***,traditional methods,involving elastomer film-based substrates or encapsulation techniques,often fall short due to mechanical mismatches,discomfort,lack of breathability,and limitations in sensing ***,there is a pressing need,yet it remains a significant challenge to create pressure sensors that are not only highly breathable,flexible,and comfortable but also sensitive,durable,and ***,we present a biocompatible and breathable fabric-based pressure sensor,using nonwoven fabrics as both the sensing electrode(coated with MXene/poly(3,4-ethylenedioxythiophene):polystyrene sulfonate[PEDOT:PSS])and the interdigitated electrode(printed with MXene pattern)via a scalable spray-coating and screen-coating *** resultant device exhibits commendable air permeability,biocompatibility,and pressure sensing performance,including a remarkable sensitivity(754.5 kPa^(−1)),rapid response/recovery time(180/110 ms),and robust cycling ***,the integration of PEDOT:PSS plays a crucial role in protecting the MXene nanosheets from oxidation,significantly enhancing the device's long-term *** outstanding features make this sensor highly suitable for applications in fullrange human activities detection and disease *** study underscores the promising future of flexible pressure sensors in the realm of intelligent wearable electronics,setting a new benchmark for the industry.

关键词： biocompatibility MXene pressure sensor screen printing textile