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Forward stagewise regression with multilevel memristor for sparse coding

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半导体学报:英文版 2023年第10期44卷 105-113页

作者： Chenxu Wu Yibai Xue Han Bao Ling Yang Jiancong Li Jing Tian Shengguang ren Yi Li Xiangshui Miao School of Integrated Circuits Huazhong University of Science and TechnologyWuhan 430074China Hubei Yangtze Memory laboratories Wuhan 430205China

Sparse coding is a prevalent method for image inpainting and feature extraction,which can repair corrupted images or improve data processing efficiency,and has numerous applications in computer vision and signal ***,sev-eral memristor-based in-memory computing systems have been proposed to enhance the efficiency of sparse coding ***,the variations and low precision of the devices will deteriorate the dictionary,causing inevitable degradation in the accuracy and reliability of the *** this work,a digital-analog hybrid memristive sparse coding system is pro-posed utilizing a multilevel Pt/Al_(2)O_(3)/AlO_(x)/W memristor,which employs the forward stagewise regression algorithm:The approxi-mate cosine distance calculation is conducted in the analog part to speed up the computation,followed by high-precision coeffi-cient updates performed in the digital *** determine that four states of the aforementioned memristor are sufficient for the processing of natural ***,through dynamic adjustment of the mapping ratio,the precision require-ment for the digit-to-analog converters can be reduced to 4 *** to the previous system,our system achieves higher image reconstruction quality of the 38 dB peak-signal-to-noise ***,in the context of image inpainting,images containing 50%missing pixels can be restored with a reconstruction error of 0.0424 root-mean-squared error.

关键词： forward stagewise regression in-memory computing memristor sparse coding

Orbital angular momentum multiplexing communication system over atmospheric turbulence with K-best detection

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Science China(Information Sciences) 2021年第9期64卷 175-186页

作者： Yingmeng GE Liang WU Chuan ZHANG Zaichen ZHANG Laboratory of Efficient Architectures for digital-communication and Signal-processing (LEAdS) Southeast University National Mobile Communications research Laboratory Southeast University Purple Mountain laboratories

As the optical communication technology advances, vortex beam with orbital angular momentum(OAM) has gained wide attention due to its potential to significantly increase the channel capacity. Under the influence of atmospheric turbulence, there are still challenging problems in the OAM multiplexing system. To the best of our knowledge, in this paper one multiple-input-multiple-output(MIMO) detection technology named K-best detection, is first applied to the OAM multiplexing system. Numerical simulation results indicate the proposed solution enhances the performance of the optical communication system compared with data-aided least mean square(dA-LMS) and minimum mean squared error(MMSE) detection. Furthermore,with MMSE sorted Qr decomposition(MMSE-SQrd) preprocessing, the performance of K-best detection can be further improved. When Cn~2= 1×10.14, about 4.4 dB signal-to-noise ratio(SNr) gain can be obtained by preprocessing at k = 2 while the complexity is not significantly increased. Computational complexity is also analyzed in this paper, results show that K-best detection with winner path extension(WPE) algorithm can achieve 43% system complexity reduction, achieving a compromise between performance and complexity in K-best detection.

关键词： orbital angular momentum atmospheric turbulence K-best detection MMSE-SQrd preprocessing WPE algorithm

AG Channel Measurements and Characteristics Analysis in Hilly Scenarios for 6G UAV Communications

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China Communications 2022年第11期19卷 32-46页

作者： Chongyang Yu Yu Liu Hengtai Chang Jingfan Zhang Mengjiao Zhang Peter Poechmueller Chengxiang Wang School of Microelectronics Shandong UniversityNo.1500Shunhua RoadGaoxin DistrictJinan 250101China National Mobile Communications research Laboratory School of Information Science and EngineeringSoutheast UniversityNo.2SipailouXuanwu DistrictNanjing 210096China Purple Mountain laboratories No.9Mozhou East RoadJiangning DistrictNanjing 211111China

As an important part of sixth generation(6G)integrated space-air-ground-sea networks,unmanned aerial vehicle(UAV)communications have aroused great attention and one of its typical application scenarios is the hilly *** related UAV air-ground(AG)channel characteristics analysis is crucial for system design and network evaluation of future UAV communications in hilly *** this paper,a recently conducted channel measurements campaign in a hilly scenario is presented,which is conducted at the center frequencies of 2.585 GHz and 3.5 GHz for different flight *** on the measurement data,some key channel characteristics are analyzed,including path loss(PL),shadow fading(SF),rician K-factor,root mean square(rMS)delay spread(dS),and temporal auto-correlation function(ACF).Finally,the comparison of typical channel characteristics under circular and straight trajectories is *** related results can provide a theoretical reference for constructing future UAV communication system in hilly scenarios.

关键词： UAV communications channel measurements channel characteristics hilly scenarios 6G

Modular Extremely Large-Scale Array Communication:Near-Field Modelling and Performance Analysis

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China Communications 2023年第4期20卷 132-152页

作者： Xinrui Li Haiquan Lu Yong Zeng Shi Jin rui Zhang National Mobile Communications research Laboratory Frontiers Science Center for Mobile Information Communication and SecuritySoutheast UniversityNanjing 210096China Purple Mountain laboratories Nanjing 211111China The Chinese University of Hong Kong Shenzhen Research Institute of Big DataShenzhen 518172China department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore

This paper investigates the wireless communication with a novel architecture of antenna arrays,termed modular extremely large-scale array(XLarray),where array elements of an extremely large number/size are regularly mounted on a shared platform with both horizontally and vertically interlaced *** module consists of a moderate/flexible number of array elements with the inter-element distance typically in the order of the signal wavelength,while different modules are separated by the relatively large inter-module distance for convenience of practical *** accurately modelling the signal amplitudes and phases,as well as projected apertures across all modular elements,we analyse the near-field signal-to-noise ratio(SNr)performance for modular XL-array *** on the non-uniform spherical wave(NUSW)modelling,the closed-form SNr expression is derived in terms of key system parameters,such as the overall modular array size,distances of adjacent modules along all dimensions,and the user's three-dimensional(3d)*** addition,with the number of modules in different dimensions increasing infinitely,the asymptotic SNr scaling laws are ***,we show that our proposed near-field modelling and performance analysis include the results for existing array architectures/modelling as special cases,e.g.,the collocated XL-array architecture,the uniform plane wave(UPW)based far-field modelling,and the modular extremely large-scale uniform linear array(XL-ULA)of *** simulation results are presented to validate our findings.

关键词： modular extremely large-scale array practical deployment projected apertures non-uniform spherical wave near-field modelling

An easily-prepared impedance matched Josephson parametric amplifier

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Chinese Physics B 2021年第6期30卷 48-51页

作者：卢亚鹏左权潘佳政江俊良魏兴雨李子硕许问渠张凯旋郭婷婷王硕曹春海许伟伟孙国柱吴培亨 research Institute of Superconductor Electronics School of Electronic Science and EngineeringNanjing UniversityNanjing 210093China Purple Mountain laboratories Nanjing 211111China

An impedance matched parametric amplifier(IMPA)with Josephson junctions is fabricated and characterized.A hybrid structure containing coplanar and strip structures is implemented to realize an impedance taper line and a plate capacitor in an LC nonlinear resonator based on Josephson *** upper plate of the capacitor is isolated with SiNx without grounding as well as the *** easily-prepared designs greatly reduce the requirements for lithography alignment and precision,which makes the fabrication process more *** experimental results show that in such IMPA a gain higher than 25 dB with a bandwidth of about 100 MHz can be *** broadband amplifier operates close to the quantum *** adjusting the working point,a higher bandwidth of about 400 MHz can be obtained with a gain of about 17 dB.

关键词： Josephson junction parametric amplification impedance matching gain and bandwidth

Maturation of Osteoblast-Like Saos-2 on Hydroxyapatite Ceramics

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High Technology Letters 2004年第2期10卷 46-50页

作者：王朝元 duan Yourong Boban Markovic James Barbara C.rolfe Howlett Zhang Xingdong Hala Zreiqat Engineering research Center in Biomaterials Sichuan University Chengdu 610064 P.R.China Yangtze Fisheries Institute Chinese Academy of Fishery Science Jingzhou 434000 P.R.China Engineering research Center in Biomaterials Sichuan University Chengdu 610064 P.R.China Chemical Safety and Toxicology laboratories School of Safety Science UNSW 2052 NSW Sydney Australia Bone Biomaterial Unit Department of Pathology UNSW 2052 NSW Sydney Australia

Hydroxyapatite ceramics (HA) has been proved to be excellent in biocompatibility and bioactivity. However, limited information is available concerning how HA ceramics affects the maturation of osteoblasts in molecular biological level in vitro. This study examines the mrNA expression and protein production of bone-related genes in osteoblast-like cell line (Saos-2) cultured on HA disks. Saos-2 cells are seeded onto the substrates and cultured for 18 days. Harvested cells are tested for the cell growth rate, expression of mrNAs for osteocalcin and alkaline phosphatase, and protein production of bone sialoprotein and osteocalcin. MTS assay shows that cell proliferates well on HA ceramic substrate. After 9d, bone sialoprotein and osteocalcin protein production in SaPS-2 increases more on HA surfaces than on control material. As bone sialoprotein and osteocalcin are the genes to be highly expressed at the late stage of osteoblast differentiation, this study reveals that after long time culture in HA, HA can induce Saos-2 maturation. The behavior of Saos-2 on HA surfaces revealed in this study provides valuable information for the understanding of the biocompatibility and bioactivity of HA ceramics.

关键词：羟磷灰石制陶业细胞增殖相关骨基因表达熟化 Saos-2 分子生物学

Planckian dissipation and non-Ginzburg-Landau type upper critical field in Bi2201

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Science China(Physics,Mechanics & Astronomy) 2023年第3期66卷 147-155页

作者： Qihao Zang Zhengyan Zhu Zuyu Xu Shichao Qi Haoran Ji Yiwen Li Jian Wang Huiqian Luo Hua-Bing Wang Hai-Hu Wen National Laboratory of Solid State Microstructures and department of Physics Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China research Institute of Superconductor Electronics Nanjing UniversityNanjing 210093China International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China Institute of Physics Chinese Academy of SciencesBeijing 100190China Purple Mountain laboratories Nanjing 211111China

resistivity and Hall effect measurements have been carried out on a micro-fabricated bridge of Bi2201 single crystal at low temperatures down to 0.4 K under high magnetic *** superconductivity is crashed by a high magnetic field,the recovered "normal state" resistivity still shows a linear temperature dependence in the low temperature *** with the effective mass and the charge carrier density,we get a linear scattering rate 1/τ=αkBT/h with 0.77 rong evidence of the Planckian ***,our results reveal a new type of temperature dependence of the upper critical field,H_(c2)(T)=H*■,which is totally different from the expectation of the Ginzburg-Landau theory,and suggests the existence of uncondensed Cooper pairs above H_(c2)(T) line.

关键词： cuprates scattering rate Planckian dessipation anomalous upper critical field

Laser speckle contrast imaging for monitoring of acutepancreatitis at ischemia-reperfusion injury of thepancreas in rats

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Journal of Innovative Optical Health Sciences 2022年第1期15卷 90-102页

作者： P.A.dyachenko(Timoshina) A.N.Bashkatov d.A.Alexandrov V.I.Kochubey V.V.Tuchin Saratov State University SaratovRussia laboratories of Biophotonics and Laser Molecular Imaging and Machine Learning National research Tomsk State University TomskRussia Saratov State Medical University SaratovRussia Institute of Precision Mechanics and Control Russian Academy of SciencesRussia A.N.Bach Institute of Biochemistry Research Center of Biotechnology of the Russian Academy of Sciences MoscowRussia

The influence of ischemia-reperfusion(I/r)action on pancreatic blood flow(PBF)and the development of acute pancreatitis(AP)in laboratory rats is evaluated in vivo by using the laser speckle contrast imaging(LSCI).Additionally,the optical properties in norm and under condition of AP in rats were assessed using a modied integrating sphere spectrometer and inverse Monte Carlo(IMC)*** results of the experimental study of microcirculation of the pancreas in 82 rats in the ischemic model are *** data obtained conrm the fact that local ischemia and changes in the blood°ow velocity of the main vessels cause and provoke acute pancreatitis.

关键词： Laser speckles contrast of speckle images adaptive algorithm microcirculation blood flow acute pancreatitis pancreas rats optical properties integrating sphere spectroscopy

基质辅助激光解吸电离飞行时间质谱技术在临床微生物鉴定中的应用

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中华检验医学杂志 2015年第1期38卷 64-66页

作者： Marc van Nuenen Kirk doing 顾兵 Alex van Belkum Mass Spectrometry Institut Merieux Clinical Affairs durham Institut Merieux 南京医科大学第一附属医院检验学部 r&d Microbiology Institut Merieux

近年来，基质辅助激光解吸电离飞行时间质谱技术（MALdI—TOF—MS）已从物理实验室走进临床微生物实验室，用于微生物的鉴定，正逐步取代由Pasteur和Koch建立的基于细菌表型的传统鉴定方法。许多欧洲微生物实验室目前正在使用MALdI-TOF... 详细信息

近年来，基质辅助激光解吸电离飞行时间质谱技术（MALdI—TOF—MS）已从物理实验室走进临床微生物实验室，用于微生物的鉴定，正逐步取代由Pasteur和Koch建立的基于细菌表型的传统鉴定方法。许多欧洲微生物实验室目前正在使用MALdI-TOF-MS，大大提高了工作效率。鉴于美国食品药品管理局已经批准其用于体外诊断，MALdI-TOF-MS将很快在美国普及应用。这也将进一步推动了质谱技术在微生物药敏和流行学分型中的发展和应用。本文综述了MALdI—TOF—MS在临床微生物实验室的应用现状，并通过多中心临床试验结果，比较不同MALdI—TOF-MS仪器获得的诊断数据，重点阐述其在临床微生物领域的相关研究和应用。

关键词：光谱法质量基质辅助激光解吸电离微生物学技术