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基于RCS序列的弹道中段目标微动提取技术

现代雷达 2012年第6期34卷 78-81页

作者：陈翱中国飞行试验研究院西安710089

对改进的"烈火2"型导弹进行电磁仿真,根据弹道类目标在空中的动力学模型及飞行姿态控制技术,模拟了弹道类目标在中段飞行过程中的雷达散射截面回波序列,通过对雷达散射截面序列的微动特性分析,进行真假弹头目标识别。文中指出传统傅里... 详细信息

对改进的"烈火2"型导弹进行电磁仿真,根据弹道类目标在空中的动力学模型及飞行姿态控制技术,模拟了弹道类目标在中段飞行过程中的雷达散射截面回波序列,通过对雷达散射截面序列的微动特性分析,进行真假弹头目标识别。文中指出传统傅里叶变换在非平稳周期序列分析中的不足,并提出了一种改进周期序列分析方法,该方法能克服傅里叶变换的不足,在应用于非平稳、复杂噪声背景下的弹道类目标雷达散射截面序列分析时,能有效的提取微动特征,从而实现对真假弹头的辨识问题。最后通过仿真实验验证了非平稳周期序列分析方法的可行性与有效性。

关键词：弹道中段雷达散射截面微多普勒非平稳周期序列

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幅相校准在机载有源相控阵雷达中的应用

现代雷达 2012年第5期34卷 17-19页

作者：陈翱中国飞行试验研究院航电所西安710089

对于机载有源相控阵雷达,天线低副瓣是最基本也是最重要的指标要求之一。有效、实时的幅度和相位校准是保证天线低副瓣指标的主要保证措施。文中详细描述了在有源相控阵天线系统中存在的幅相误差原理,给出了对幅度和相位进行实时校准的... 详细信息

对于机载有源相控阵雷达,天线低副瓣是最基本也是最重要的指标要求之一。有效、实时的幅度和相位校准是保证天线低副瓣指标的主要保证措施。文中详细描述了在有源相控阵天线系统中存在的幅相误差原理,给出了对幅度和相位进行实时校准的算法,同时也给出了校准剩余误差的验证方法,并通过软件流程框图给出了实时校准的流程,最后,通过在真实雷达中的实验结果验证了该方法的可行性和正确性。

关键词：机载雷达校准幅度相位副瓣

Decoration of C_(60) nanorods with nickel and their magnetic properties

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Chinese Science Bulletin 2009年第14期54卷 2539-2542页

作者： chen ao LIU BingBing HOU YuanYuan WEN GeHui LIU DeDi LU Shuangchen LI ZePeng LI XiangLin ZOU YongGang ZOU Bo LI DongMei CUI Tian ZOU GuangTian State Key Laboratory of Superhard Materials Jilin University Changchun 130012 China

We studied the coating of C60 nanorods with nickel by electroless plating method and investigated their magnetic properties. The morphology and structure of the nickel layer coated on C60 nanorods were characterized by transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and Raman spectroscopy. The coated nickel is in the form of nano-sized crystals and becomes a continuous layer as reaction time increases. The hysteresis loop shows a super paramagnetic characteristic similar to that of nanometer-sized nickel particle. These results suggest that the average size of nickel particles on C60 rods is below 10 nm. Our study has shown that electroless plating is an efficient and simple method for coating C60 nanorods with nickel.

关键词：纳米镍粒子 C60 磁学性质透射电子显微镜纳米涂层装饰化学镀镍 X射线光谱

Deep learning methods for noisy sperm image classification from convolutional neural network to visual transformer:a comprehensive comparative study

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Intelligent Medicine 2024年第2期4卷 114-127页

作者： ao chen chen Li Md Mamunur Rahaman Yudong Yao Haoyuan chen Hechen Yang Peng Zhao Weiming Hu Wanli Liu Shuojia Zou Ning Xu Marcin Grzegorzek Microscopic Image and Medical Image Analysis Group College of Medicine and Biological Information EngineeringNortheastern UniversityShenyangLiaoning 110169China Department of Electrical and Computer Engineering Stevens Institute of TechnologyHobokenNJ 07030USA School of Arts and Design Liaoning Petrochemical UniversityFushunLiaoning 113001China Institute of Medical Informatics University of LübeckLüebeckGermany

Background With the gradual increase of infertility in the world,among which male sperm problems are the main factor for infertility,more and more couples are using computer-assisted sperm analysis(CASA)to assist in the analysis and treatment of ***,the rapid development of deep learning(DL)has led to strong results in image classification ***,the classification of sperm images has not been well studied in current deep learning methods,and the sperm images are often affected by noise in practical CASA *** purpose of this article is to investigate the anti-noise robustness of deep learning classification methods applied on sperm *** The SVIA dataset is a publicly available large-scale sperm dataset containing three *** this work,we used subset-C,which provides more than 125,000 independent images of sperms and impurities,including 121,401 sperm images and 4,479 impurity *** investigate the anti-noise robustness of deep learning classification methods applied on sperm images,we conducted a comprehensive comparative study of sperm images using many convolutional neural network(CNN)and visual transformer(VT)deep learning methods to find the deep learning model with the most stable anti-noise *** This study proved that VT had strong robustness for the classification of tiny object(sperm and impurity)image datasets under some types of conventional noise and some adversarial *** particular,under the influence of Poisson noise,accuracy changed from 91.45%to 91.08%,impurity precison changed from 92.7%to 91.3%,impurity recall changed from 88.8%to 89.5%,and impurity F1-score changed 90.7%to 90.4%.Meanwhile,sperm precision changed from 90.9%to 90.5%,sperm recall changed from 92.5%to 93.8%,and sperm F1-score changed from 92.1%to 90.4%.Conclusion Sperm image classification may be strongly affected by noise in current deep learning methods;the robustness with regard to noise of VT methods based

关键词： Computer-assisted sperm analysis Anti-noise Robustness Deep learning .Image classification Sperm image Conventional noise Adversarial attacks Convolutional neural network Visual transformer

Mitigating Deep Dielectric Charging Effects at the Orbits of Jovian Planets

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Transactions of Nanjing University of Aeronautics and Astronautics 2020年第5期37卷 804-815页

作者： YU Xiangqian SONG Siyu chen Hongfei ZONG Qiugang ZOU Hong SHI Weihong chen ao School of Earth and Space Sciences Peking UniversityBeijing 100871P.R.China

Deep dielectric charging/discharging,caused by high energy electrons,is an important consideration in electronic devices used in space environments because it can lead to spacecraft anomalies and *** Jovian planets,including Saturn,Uranus,Neptune and Jupiter’s moons,are believed to have robust electron radiation belts at relativistic *** particular,Jupiter is thought to have caused at least 42 internal electrostatic discharge events during the Voyager 1 *** the development of deep space exploration,there is an increased focus on the deep dielectric charging effects in the orbits of Jovian *** this paper,GEANT4,a Monte Carlo toolkit,and radiation-induced conductivity(RIC)are used to calculate deep dielectric charging effects for Jovian *** results are compared with the criteria for preventing deep dielectric charging effects in Earth *** findings show that effective criteria used in Earth orbit are not always appropriate for preventing deep dielectric charging effects in Jovian ***,Io,Europa,Saturn(R_S=6),Uranus(L=4.73)and Ganymede missions should have a thicker shield or higher dielectric conductivity,while Neptune(L=7.4)and Callisto missions can have a thinner shield thickness or a lower dielectric ***,dielectrics grounded with double metal layers and thinner dielectrics can also decrease the likelihood of discharges.

关键词： Jovian planets orbits Earth orbits deep dielectric charging effect space radiation

Experimental exploration of five-qubit quantum error-correcting code with superconducting qubits

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National Science Review 2022年第1期9卷 100-106页

作者： Ming Gong Xiao Yuan Shiyu Wang Yulin Wu Youwei Zhao chen Zha Shaowei Li Zhen Zhang Qi Zhao Yunchao Liu Futian Liang Jin Lin Yu Xu Hui Deng Hao Rong He Lu Simon C.Benjamin cheng-Zhi Peng Xiongfeng Ma Yu-ao chen Xiaobo Zhu Jian-Wei Pan Hefei National Laboratory for Physical Sciences at the Microscale and Department of Modern Physics University of Science and Technology of China Shanghai Branch CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics University of Science and Technology of China Shanghai Research Center for Quantum Sciences Center for Quantum Information Institute for Interdisciplinary Information Sciences Tsinghua University Department of Materials University of Oxford

Quantum error correction is an essential ingredient for universal quantum computing.D espite tremendous experimental efforts in the study of quantum error correction,to date,there has been no demonstration in the realis ation of universal quantum error-correcting code,with the subsequent verification of all key features including the identification of an arbitrary physical error,the capability for transversal manipulation of the logical state and state *** address this challenge,we experimentally realise the [5,1,3]code,the so-called smallest perfect code that permits corrections of generic single-qubit *** the experiment,having optimised the encoding circuit,we employ an array of superconducting qubits to realise the [5,1,3] code for several typical logical states including the magic state,an indispensable resource for realising non-Clifford *** encoded states are prepared with an average fidelity of 57.1(3)% while with a high fidelity of 98.6(1)% in the code ***,the arbitrary single-qubit errors introduced manually are identified by measuring the *** further implement logical Pauli operations with a fidelity of 97.2(2)% within the code ***,we realise the decoding circuit and recover the input state with an overall fidelity of 74.5(6)%,in total with 92 *** work demonstrates each key aspect of the [5,1,3] code and verifies the viability of experimental realisation of quantum error-correcting codes with superconducting qubits.

关键词： quantum error-correcting code superconducting qubit five-qubit code error detection logical operation

Remanufacturing Closed-Loop Supply Chain Model with Radio Frequency Identification Affecting Recycling Rate

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Journal of Donghua University(English Edition) 2016年第6期33卷 933-938页

作者： YANG Ai-feng WAN Si chen ao School of Management Hefei University of Technology Hefei 230009 China

In order to construct a resource-saving and environment- friendly society, the advantages of radio frequency identification （RFID） were considered. And it put forward the idea of introducing RFID in the recycling activities of waste products. Taking into account such elements as the technical level of RFID, cost saving from remanufacturing and the cost of RFID tags, both centralized and decentralized supply chain models with different participants in waste product collection were created, in order to determine the optimal pricing strategy and RFID technical level. In the end, sensitivity analyses were conducted to analyze the impacts of scaling parameter for additional increased recovery rate with RFED on pricing and RFID technology level, and impacts of cost saving on the profits of participants in different remanufacturing closed-loop supply chain models.

关键词： radio frequency identification(RFID) technology closedloop supply chain remanufacturing Stackelberg game pricing

噪声鉴别C均值聚类的滁菊花茶品质等级鉴别研究

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光谱学与光谱分析 2024年第8期44卷 2202-2207页

作者：武斌谢晨傲陈勇武小红贾红雯滁州职业技术学院信息工程学院安徽滁州239000 江苏大学电气信息工程学院江苏镇江212013

近红外光谱检测技术可以通过探测近红外区域的光谱特征,反映所测样品内部有机物化学成分和结构信息。在分析物质成分时,近红外光谱通常会涉及到大量的波长数据,因此其维数往往比较高。同时,光谱会出现重叠和冗余等现象,会影响模型的性... 详细信息

近红外光谱检测技术可以通过探测近红外区域的光谱特征,反映所测样品内部有机物化学成分和结构信息。在分析物质成分时,近红外光谱通常会涉及到大量的波长数据,因此其维数往往比较高。同时,光谱会出现重叠和冗余等现象,会影响模型的性能。提出一种噪声鉴别C均值聚类(NDCM)算法。NDCM将一种快速广义噪声聚类(FGNC)和模糊线性判别分析(FLDA)相结合,可实现模糊聚类过程中进行数据鉴别信息的提取和数据空间维度的压缩,以达到更高的聚类准确率。对滁菊花茶近红外光谱数据进行模糊C均值聚类(FCM)得到的模糊隶属度和聚类中心作为噪声鉴别C均值聚类(NDCM)的初始模糊隶属度和初始聚类中心,使NDCM具有聚类速度快,准确率高等优点。FCM算法对光谱噪声数据敏感,而NDCM算法在处理含噪声的光谱数据时能够表现出较好的性能。该研究选取特级滁菊、一级滁菊、二级滁菊三种品质等级的滁菊花茶作为实验样本,共计240个样本。实验使用便携式近红外光谱仪(NIR-M-F1-C)采集滁菊花茶的近红外光谱数据。用Savitzky-Golay滤波和多元散射校正(MSC)对滁菊花茶近红外光谱进行预处理,以减少光谱中掺杂的噪声和重叠信息。通过主成分分析(PCA)对采集到的400维光谱数据进行维度压缩降至6维。该研究使用线性判别分析(LDA)提取滁菊花茶光谱数据中的鉴别信息,并将数据空间维度进一步转换为2维。分别用FCM,FGNC和NDCM三种算法对处理后的数据进行聚类分析,以实现对滁菊花茶的准确分类。实验结果显示:当权重指数m=2.5时,FCM,FGNC,NDCM的聚类准确率分别为92.42%,98.48%,100%。NDCM聚类时间略长于FGNC。FCM算法需要进行27次迭代才能收敛,而FGNC算法和NDCM算法分别只需要13次和10次迭代就能达到收敛。采用近红外光谱技术结合MSC、Savitzky-Golay滤波、PCA、LDA和NDCM算法,建立了一种精准鉴别滁菊花茶品质等级的聚类模型。

关键词：噪声鉴别C均值聚类近红外光谱无损检测线性判别分析

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铝合金激光熔化沉积应力场及力学性能分析

焊接学报 2020年第4期41卷 62-66,I0008页

作者：陶汪王宪陈奥李俐群哈尔滨工业大学先进焊接与连接国家重点试验室哈尔滨150001

采用激光熔化沉积工艺对6 mm厚的ZL114A铝板中的通槽进行了修复试验.试验中采用AlSi10Mg粉末作为沉积过程的填充材料.为了选择合适的激光扫描方法,通过数值模拟的方式,探究了不同扫描路径下产生的残余应力情况.模拟结果显示,相比于自一... 详细信息

采用激光熔化沉积工艺对6 mm厚的ZL114A铝板中的通槽进行了修复试验.试验中采用AlSi10Mg粉末作为沉积过程的填充材料.为了选择合适的激光扫描方法,通过数值模拟的方式,探究了不同扫描路径下产生的残余应力情况.模拟结果显示,相比于自一侧向另一侧平行扫描,自下向上逐层扫描方式更有助于减小残余应力,残余应力分布也更均匀.采用自下向上的逐层扫描方式实现了铝板通槽的激光熔化沉积的工艺试验,并探索了缺陷及热输入对试件力学性能的影响.结果表明,通过工艺试验得到的沉积试件,最优性能的试件抗拉强度为268 MPa,达到母材的89%.试件断裂并未沿着沉积区与母材的界面处断裂,而是在沉积区内部层与层界面间的搭接区域断裂.

关键词：激光熔化沉积力学性能应力场数值模拟