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Microwave metamaterials: from exotic physics to novel information systems

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Frontiers of Information Technology & Electronic Engineering 2020年第1期21卷 4-26页

作者： Rui-yuan WU tie-jun CUI State Key Laboratory of Millimeter Waves Southeast UniversityNanjing 210096China Synergetic Innovation Center of Wireless Communication Technology Southeast UniversityNanjing 210096China

Metamaterials and metasurfaces have attracted much attention due to their powerful ability to control electromagnetic(EM)*** this paper,we review the recent developments in the field of EM metamaterials,starting from their exotic physics to their applications in novel information ***,we show the fundamental understanding on traditional metamaterials based on the effective medium theory and related applications,such as invisibility cloaks and ***,we review the two-dimensional versions of metamaterials,i.e.,metasurfaces,for controlling spatial waves and surface waves and thereafter present their typical *** particular,we briefly introduce spoof surface plasmon polaritons and their applications in microwave *** the above approach,we emphatically present the concepts of digital coding metamaterials,programmable metamaterials,and information *** extending the principles of information science to metamaterial designs,several functional devices and information systems are presented,which enable digital and EM-wave manipulations ***,we give a brief summary of the development prospects for microwave metamaterials.

关键词： Metamaterial Effective medium theory Metasurface Surface plasmon polaritons Digital coding Programmable Information

Extensible on-chip mode manipulations based on metamaterials

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Light(Science & Applications) 2022年第8期11卷 1637-1638页

作者： Xuanru Zhang tie jun Cui State Key Laboratory of Millimeter Waves and Institute of Electromagnetic Space School of Information Science and EngineeringSoutheast UniversityNanjing210096China

An extensible framework is proposed for on-chip spatial-mode manipulations based on metamaterial building blocks,which enables the excitation of arbitrarily high-order spatial modes in silicon *** makes a significant step towards the comprehensive and on-chip manipulations of spatial lights,and may provide promising opportunities for complex photonic functionalities.

关键词： chip mode excitation

83.3 dtex/36 f高弹抗静电涤纶DTY的生产工艺

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合成纤维 2024年第6期53卷 9-12页

作者：张英辉沈军钟伟强朱秀庆沈重仪王铁军荣盛石化股份有限公司浙江杭州311247

在聚酯反应中加入纳米级膨润土、海藻酸钠和导电性钛酸钾晶须等制得抗静电改性聚酯熔体,通过纺丝加工成预取向纤维,再经优化牵伸倍数、假捻速比(D/Y)、定型温度等加弹工艺制得高弹、抗静电涤纶拉伸变形丝(DTY)。经过实践证明:加工速度在... 详细信息

在聚酯反应中加入纳米级膨润土、海藻酸钠和导电性钛酸钾晶须等制得抗静电改性聚酯熔体,通过纺丝加工成预取向纤维,再经优化牵伸倍数、假捻速比(D/Y)、定型温度等加弹工艺制得高弹、抗静电涤纶拉伸变形丝(DTY)。经过实践证明:加工速度在800 m/min,第一热箱温度控制在200℃以内,成品断丝少、毛丝少,变形效果佳;将牵伸倍数控制在1.77倍,同时选择D/Y为1.73,生产的DTY质量较好,毛丝和僵丝的比例较低,同时其物理性质满足要求。为了改善产品的集束性,提高产品的高弹性和可加工性,第二热箱温度设置为130℃,网络压力设置为0.16 MPa。

关键词：细旦涤纶高弹性抗静电性生产工艺

Meta-analysis with zero-event studies:a comparative study with application to COVID-19 data

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Military Medical Research 2022年第1期9卷 126-137页

作者： Jia-Jin Wei En-Xuan Lin Jian-Dong Shi Ke Yang Zong-Liang Hu Xian-Tao Zeng tie-jun Tong department of Mathematics Hong Kong Baptist UniversityHong KongChina Shenzhen Research Institute of Big Data ShenzhenChina College of Mathematics and Statistics Shenzhen UniversityShenzhenChina Center for Evidence-Based and Translational Medicine Zhongnan Hospital of Wuhan UniversityWuhanChina.

Background:Meta-analysis is a statistical method to synthesize evidence from a number of independent studies,including those from clinical studies with binary *** practice,when there are zero events in one or both groups,it may cause statistical problems in the subsequent ***:In this paper,by considering the relative risk as the effect size,we conduct a comparative study that consists of four continuity correction methods and another state-of-the-art method without the continuity correction,namely the generalized linear mixed models(GLMMs).To further advance the literature,we also introduce a new method of the continuity correction for estimating the relative ***:From the simulation studies,the new method performs well in terms of mean squared error when there are few *** contrast,the generalized linear mixed model performs the best when the number of studies is *** addition,by reanalyzing recent coronavirus disease 2019(COVID-19)data,it is evident that the double-zero-event studies impact the estimate of the mean effect ***:We recommend the new method to handle the zero-event studies when there are few studies in a meta-analysis,or instead use the GLMM when the number of studies is *** double-zero-event studies may be informative,and so we suggest not excluding them.

关键词： Continuity correction Coronavirus disease 2019 data Meta-analysis Relative risk Zero-event studies

加强科技创新能力建设推动钢铁工业高质量发展

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冶金经济与管理 2024年第1期 1-1页

作者：范铁军冶金工业规划研究院

当前,全球百年未有之大变局加速演进,世界经济增长放缓,地缘冲突加剧,影响了诸多国家经济可持续发展。新一轮的科技革命和产业发展在不断深化。我国经济逐步由高速增长阶段转向高质量发展阶段,经济发展进入新常态。2023年前三季度,我国... 详细信息

当前,全球百年未有之大变局加速演进,世界经济增长放缓,地缘冲突加剧,影响了诸多国家经济可持续发展。新一轮的科技革命和产业发展在不断深化。我国经济逐步由高速增长阶段转向高质量发展阶段,经济发展进入新常态。2023年前三季度,我国国内生产总值(GDP)为91.3万亿元,同比增长5.2%。国内经济面临增长速度换挡期、结构调整阵痛期、前期刺激政策消化期“三期叠加”的复杂局面,推动高质量发展势在必行。

关键词：高速增长阶段科技创新能力刺激政策钢铁工业阵痛期新常态高质量发展增长速度

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脉冲连续摄影原理与超高速高动态成像验证

电子学报 2022年第12期50卷 2919-2927页

作者：黄铁军北京大学计算机学院多媒体信息处理全国重点实验室北京100871

传统相机采用定时曝光方式获得静态图像或图像序列形式的视频,不能有效表达极高速的光子流过程,而且导致高速和高动态相互对立的“两难困境”.基于光电传感器像素独立的特点,提出了连续摄影原理:每个像素各自把接收的光子流转换成电子流... 详细信息

传统相机采用定时曝光方式获得静态图像或图像序列形式的视频,不能有效表达极高速的光子流过程,而且导致高速和高动态相互对立的“两难困境”.基于光电传感器像素独立的特点,提出了连续摄影原理:每个像素各自把接收的光子流转换成电子流,连续测量光电流并转换成数字信息流,实现像素级别的连续表达,再按照像素空间排布组成序列阵列,就是对像素平面入射光子流过程的连续表达.截取序列阵列任何一个时刻的状态就可得到该时刻的图像,从而实现连续成像.进而,提出了把光电子流调制为脉冲序列的脉冲连续摄影原理:像素从清空状态开始积累电荷,达到额定阈值时产生一个脉冲作为积满标志并自动复位重新开始累积,如此重复.一个脉冲积满所经历的时间称为它的脉宽,与这个时段的光强成反比,据此可以估计这一时段的光强.脉冲按照自然时序排列而成的脉冲序列就是对光电子流过程的数字化表达.各像素产生的脉冲流按照像素空间分布排列而成的脉冲流阵列称为视象,蕴含了光过程丰富的时空信息,从中可以生成任意时刻的图像,实现超高速、高动态、无模糊连续成像,解决了定时曝光成像的“两难困境”.脉冲连续摄影原理的唯一参数是累积阈值Q,对应积满一个脉冲所需光子/电子数,唯一变量是脉冲累积时长τ,是最容易准确测量的物理量,并可以利用自然时序简练表达.任意时刻的光强为Q/τ,由所处脉冲的宽度τ决定,τ的取值范围是(0,∞),因此理论上可以表达任意强度的光,动态范围无穷大.实际物理实现中,强光表达的极限取决于电路最短读出时间,暗光表达极限就是暗电流强度,它累积为一个脉冲的时长■即相机的动态范围,采用常规光电器件和电路就能实现160 dB甚至180 dB超高动态成像.在要求成像时间灵敏度小于■时,可通过对累积电压亚阈值量化,实现超高动态成像.光子流和光电子流是符合泊松分布的离散随机过程,往往是一个“分段线性”过程光强瞬时突变,突变之间光强稳定.提出了实现脉冲流最简无损压缩的首脉冲编码方法:只在光强变化时输出首脉冲发放时刻及其脉宽,之后不输出脉冲就表示重复.采用首脉冲序列编码,可在几乎不增加输出数据量条件下,大幅提高时间计量精度,显著提升系统的动态范围和时间灵敏度.采用成熟CMOS光电器件和标准工艺,研制了两款脉冲连续摄影芯片和脉冲相机,空间分辨率分别为10万像素和100万像素,采用4万赫兹同步脉冲输出,即最短脉宽25μs.实拍试验验证了脉冲连续摄影原理的可实现性和超高速高动态无模糊成像性能.脉冲连续摄影视象蕴含了光子流的时空信息,替代图像和视频,将从根本上重塑计算机视觉和视觉信息处理技术和产业.创立了脉冲视觉开源算法体系SpikeCV,用较低计算复杂度实现了速度比人眼快千倍的超高速目标检测跟踪识别系统.作为脉冲连续摄影的对称过程,脉冲连续显示把超高速脉冲流调制为极高速光子流,能够实现类似自然光的高速变化,解决了传统显示系统因为低帧率带来的运动模糊和视觉疲劳眩晕等问题.连续摄影和连续显示相结合,可实现近似玻璃的单向透明显示和超高速无介质光通信.

关键词：光电传感器脉冲序列调制连续摄影高动态成像超高速成像相机视象

A metasurface-based light-to-microwave transmitter for hybrid wireless communications

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Light(Science & Applications) 2022年第6期11卷 1139-1148页

作者： Xin Ge Zhang Ya Lun Sun Bingcheng Zhu Wei Xiang Jiang Qian Yu Han Wei Tian Cheng-Wei Qiu Zaichen Zhang tie jun Cui State Key Laboratory of Millimeter Waves School of Information Science and EngineeringSoutheast University210096 NanjingChina National Mobile Communications Research Laboratory School of Information Science and EngineeringSoutheast University210096 NanjingChina Frontiers Science Center for Mobile Information Communication and Security Southeast University210096 NanjingChina Purple Mountain Laboratories 211111 NanjingChina Department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore

Signal conversion plays an important role in many applications such as communication,sensing,and *** signal conversion between optical and microwave frequencies is a crucial step to construct hybrid communication systems that combine both optical and microwave wireless technologies to achieve better features,which are highly desirable in the future wireless ***,such a signal conversion process typically requires a complicated relay to perform multiple operations,which will consume additional hardware/time/energy ***,we report a light-to-microwave transmitter based on the time-varying and programmable metasurface integrated with a high-speed photoelectric detection circuit into a *** a transmitter can convert a light intensity signal to two microwave binary frequency shift keying signals by using the dispersion characteristics of the metasurface to implement the frequency division *** illustrate the metasurface-based transmitter,a hybrid wireless communication system that allows dual-channel data transmissions in a light-to-microwave link is demonstrated,and the experimental results show that two different videos can be transmitted and received simultaneously and *** metasurface-enabled signal conversion solution may enrich the functionalities of metasurfaces,and could also stimulate new information-oriented applications.

关键词： microwave surface light

Active odd-mode-metachannel for single-conductor systems

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Opto-Electronic Advances 2022年第8期5卷 1-10页

作者： Pei Hang He Ling Yun Niu Yi Fan Hao Chi Zhang Le Peng Zhang Dayue Yao Wen Xuan Tang tie jun Cui State Key Laboratory of Millimeter Waves Southeast UniversityNanjing 210096China Institute of Electromagnetic Space Southeast UniversityNanjing 210096China

Although tremendous efforts have been devoted to investigating planar single-conductor circuits,it remains challenging to provide tight confinement of electromagnetic field and compatibility with active semi-conductor components such as amplifier,harmonic generator and ***-conductor spoof surface plasmon polariton(SSPP)structure,which is one of the most promising planar single-conductor transmission media due to the outstanding field confinement,still suf-fers from the difficulty in integrating with the active semi-conductor *** this paper,a new kind of odd-mode-metachannel(OMM)that can support odd-mode SSPPs is proposed to perform as the fundamental transmission chan-nel of the single-conductor *** introducing zigzag decoration,the OMM can strengthen the field confinement and broaden the bandwidth of odd-mode SSPPs *** importantly,the active semi-conductor amplifier chip integration is achieved by utilizing the intrinsic potential difference on OMM,which breaks the major obstacle in im-plementing the single-conductor *** an instance,an amplifier is successfully integrated on the single-conductor OMM,which can realize both loss compensation and signal ***,the merits of OMM including crosstalk suppression,low radar cross section(RCS),and flexibility are comprehensively ***,the pro-posed OMM and its capability to integrate with the active semi-conductor components may provide a new avenue to fu-ture single-conductor conformal systems and smart skins.

关键词： odd-mode spoof surface plasmon polariton single-conductor system amplifier crosstalk suppression low RCS flexibility

刘铁军教授“扶正固本消积”学说的构建与应用

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中西医结合肝病杂志 2024年第7期34卷 577-581页

作者：苏博扬熊壮王松冷炎王汉黄旭鹏桑子淇刘铁军长春中医药大学中医学院长春130117 长春中医药大学附属医院

刘铁军教授在精研中医经典理论的基础上,基于脏毒腑秽学说,针对“脏毒”这一危重阶段,针对性提出了“扶正固本消积”学说。刘铁军教授以扶正气、固本源、消积毒为主要思想指导,指出消化系统疾病的致病因素包括食、痰、瘀、秽、浊等均可... 详细信息

刘铁军教授在精研中医经典理论的基础上,基于脏毒腑秽学说,针对“脏毒”这一危重阶段,针对性提出了“扶正固本消积”学说。刘铁军教授以扶正气、固本源、消积毒为主要思想指导,指出消化系统疾病的致病因素包括食、痰、瘀、秽、浊等均可概括为积,在消积过程中注重对机体本源及正气的固护,以达到“扶正以助消积,消积以复正气”的目的。刘铁军教授总结出扶正补虚、运脾托毒、化癥消积3种治法,针对疾病的前中后期予以治疗,包括预防与预后的过程中均有不同偏重,以指导治疗消化系统疾病。

关键词：脏毒腑秽学说扶正固本消积学说扶正补虚运脾托毒化癥消积