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Photonics Research 2019年第1期7卷 80-88页

作者： yueyi yuan KUANG ZHANG XUMIN DING BADREDDINE RATNI SHAH NAWAZ BUROKUR QUN WU Department of Microwave Engineering Harbin Institute of Technology State Key Laboratory of Millimeter Waves LEME UPL Université Paris Nanterre

Polarization manipulation is a significant issue for artificial modulation of the electromagnetic(EM) wave, but general mechanisms all suffer the restriction of inherent symmetric properties between opposite ***, a strategy to independently and arbitrarily manipulate the EM wave with orthogonal circular polarizations based on a metasurface is proposed, which effectually breaks through traditional symmetrical characteristics between orthogonal handedness. By synthesizing the propagation phase and geometric phase, the appropriate Jones matrix is calculated to obtain independent wavefront manipulation of EM waves with opposite circular polarizations. Two transmissive ultra-thin meta-deflectors are proposed to demonstrate the asymmetrical refraction of transmitted circularly polarized waves in the microwave region. Simulated transmitted phase front and measured far-field intensity distributions are in excellent agreement, indicating that the transmitted wave with different polarizations can be refracted into arbitrary and independent directions within a wide frequency band(relative bandwidth of 25%). The results presented in this paper provide more freedom for the manipulation of EM waves, and motivate the realizations of various polarization-independent properties for all frequency spectra.

关键词： Polarization manipulation general mechanisms effectually breaks

Active metasurface in reflection manner for generation of reconfigurable OAM vortex beams

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Journal of Information and Intelligence 2023年第3期1卷 197-206页

作者： Yunfei Liu yueyi yuan Qun Wu Kuang Zhang The School of Electronic and Information Engineering Harbin Institute of TechnologyHarbin 150001China

In this paper,we proposed an active metasurface in reflection manner that can generate reconfigurable OAM vortex beams with high purity in the *** metasurface has a high reflectance of 0.94 and achieves a phase coverage of 320between 9.8 GHz and 11 ***,by encoding the phase distribution of the meta-atoms,various OAM vortex beams including 1,2,3,and 4 orders are generated,where the purity of all modes can be above 70%.Moreover,the metasurface can also deflect the OAM beam with a certain angle while maintaining high purity,which can be applied to reduce the influence of the alignment deviation between transmitting and receiving antennas during the communication *** a validation,the metasurface composed of 30×30 meta-atoms is fabricated and *** simulation and measurement results demonstrate the capability of the proposed metasurface to generate reconfigurable OAM beams with high purity,indicating the application potentials of proposed meta-devices in future OAM communications.

关键词： Orbital angular momentum(OAM) Active metasurface Reconfigurable High purity X-band

Dual-band independent phase control based on high efficiency metasurface[Invited]

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Chinese Optics Letters 2021年第10期19卷 7-14页

作者： Jinxing Li yueyi yuan Qun Wu Shah Nawaz Burokur Kuang Zhang Department of Microwave Engineering Harbin Institute of TechnologyHarbin 150001China LEME UPLUniversite Paris NanterreF92410 Ville d'AvrayFrance

A general method to realize arbitrary dual-band independent phase control is proposed and demonstrated in this paper.A double-layered C-shape reflective meta-atom is designed to realize independent phase control with high *** a proof of concept,we propose two functional metasurfaces in the microwave region;the first metasurface performs beam steering in different directions,and the second metasurface generates achromatic beam steering at two distinct *** simulation and measurement results agree well with the theoretical *** maximum measured efficiency is 88.7%and 92.3%at 6.8 GHz and 8.0 GHz,respectively,for one metasurface,and 91.0%and 89.8%at 6.9 GHz and8.6 GHz,respectively,for the other.

关键词： dual-band independent phase control microwave metasurface high efficiency reflection geometric phase

微波波段涡旋波束的多模式集成与动态调控研究进展

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电子与信息学报 2024年第5期46卷 1865-1873页

作者：袁乐眙杨德生刘云飞张狂哈尔滨工业大学电子与信息工程学院哈尔滨150001

该文回顾并总结了近期关于涡旋波束多模式集成与动态调控的研究成果与进展。首先从无源超表面透镜出发,利用传播相位与几何相位的综合调控作用,在单一超表面平台上实现了分数模涡旋波束的高纯度激发。更进一步,基于无源式超表面的多模... 详细信息

该文回顾并总结了近期关于涡旋波束多模式集成与动态调控的研究成果与进展。首先从无源超表面透镜出发,利用传播相位与几何相位的综合调控作用,在单一超表面平台上实现了分数模涡旋波束的高纯度激发。更进一步,基于无源式超表面的多模式涡旋集成理论及方法,通过在超表面单元结构中加载变容二极管等有源可调谐式器件,实现涡旋波束的动态切换与人工调控。并在此基础上,对基于超表面的涡旋通信系统实现信道建模,并对涡旋通信系统的性能做出了理论分析与评估,为提高现代通信系统信道容量及信息传输速率打下理论基础。

关键词：微波超表面涡旋波束多模式OAM集成可重构调控 OAM通信

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圆极化复用型多功能超构表面研究进展

电波科学学报 2021年第6期36卷 839-848页

作者：袁乐眙张狂王禹翔吴群哈尔滨工业大学电子与信息工程学院

文中回顾并总结了课题组近期关于圆极化复用型多功能超构表面的研究进展.从几何相位在正交圆极化波作用下的共轭对称响应出发,基于超构表面的等效琼斯矩阵提出了交叉极化双通道复用的独立调控方法,突破了几何相位的交叉极化耦合限制.进... 详细信息

文中回顾并总结了课题组近期关于圆极化复用型多功能超构表面的研究进展.从几何相位在正交圆极化波作用下的共轭对称响应出发,基于超构表面的等效琼斯矩阵提出了交叉极化双通道复用的独立调控方法,突破了几何相位的交叉极化耦合限制.进一步,基于同极化与交叉极化分量间的幅相关系,提出了三通道复用的多元波前集成方法,实现了对透射圆极化电磁能量的全场调控.在此基础上,通过引入手性诱导相位提出了圆极化四(全)通道复用的波前调控方法,有效提高了对圆极化电磁能量的利用效率,为提高现代通信系统信道容量及信息传输速率打下理论基础.

关键词：超构表面圆极化电磁波波前调控多功能超构透镜几何相位

基于骨干节点安全角色层级化的WSN安全模型

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重庆邮电大学学报（自然科学版） 2019年第5期31卷 722-728页

作者：魏琴芳袁岳义胡向东重庆邮电大学通信与信息工程学院重庆400065 重庆邮电大学自动化学院重庆400065

限于高度开放、节点众多且资源严重不足等因素,无线传感网(wireless sensor network,WSN)的安全管理面临着巨大挑战。提出了一种基于骨干节点安全角色层级化的WSN安全模型,通过遴选安全管理节点,划分子网的方式实现能量优化以及节点信... 详细信息

限于高度开放、节点众多且资源严重不足等因素,无线传感网(wireless sensor network,WSN)的安全管理面临着巨大挑战。提出了一种基于骨干节点安全角色层级化的WSN安全模型,通过遴选安全管理节点,划分子网的方式实现能量优化以及节点信任管理,从能效和安全角度提升网络性能。仿真测试结果表明,该方案在强化WSN安全性的同时,仍可节省约25.9%的网络能量消耗,且随着网络规模的扩大其优势将更加明显,为提升WSN的安全管理效率提供了可行的新思路。

关键词：无线传感网安全骨干节点角色层级化

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圆极化解耦手性辅助超表面

无线电工程 2022年第2期52卷 216-220页

作者：王禹翔袁乐眙李金星吴群张狂哈尔滨工业大学电子与信息工程学院黑龙江哈尔滨150001

设计了一种圆极化手性辅助微波段超表面,根据手性结构的自旋相关响应特点,通过调节单元中圆弧的张角可以独立改变左旋/右旋圆极化波的反射相位,同时反射的同极化波束幅度能维持较高水平。为了证明所提出单元的有效性,分别设计了左右旋... 详细信息

设计了一种圆极化手性辅助微波段超表面,根据手性结构的自旋相关响应特点,通过调节单元中圆弧的张角可以独立改变左旋/右旋圆极化波的反射相位,同时反射的同极化波束幅度能维持较高水平。为了证明所提出单元的有效性,分别设计了左右旋波束独立偏转和携带不同拓扑电荷数的涡旋波束2个超表面。仿真结果表明,所提出的单元能够有效对2个正交圆极化波束进行解耦使其独立工作。该方法也可以拓展到其他频率,为电磁波极化复用提供一种新的思路。

关键词：圆极化解耦手性单元超表面涡旋波束

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Insight Into the Separation-of-Variable Methods for the Closed-Form Solutions of Free Vibration of Rectangular Thin Plates

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 329-355页

作者： Yufeng Xing Ye yuan Gen Li Institute of Solid Mechanics Beihang University(BUAA)Beijing100191China

The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytical solutions for free vibration and eigenbuckling of rectangular plates and circular cylindrical *** taking the free vibration of rectangular thin plates as an example,this work presents the theoretical framework of the SOV methods in an instructive way,and the bisection–based solution procedures for a group of nonlinear eigenvalue ***,the explicit equations of nodal lines of the SOV methods are presented,and the relations of nodal line patterns and frequency orders are *** is concluded that the highly accurate SOV methods have the same accuracy for all frequencies,the mode shapes about repeated frequencies can also be precisely captured,and the SOV methods do not have the problem of missing roots as well.

关键词： Separation-of-variable method Rayleigh quotient nodal line eigenvalue equation bisection method

The dopaminergic system and Alzheimer's disease

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Neural Regeneration Research 2025年第9期20卷 2495-2512页

作者： Yuhan Zhang yuan Liang Yixue Gu International Medical College Chongqing Medical UniversityChongqingChina College of Pharmacy Chongqing Medical UniversityChongqingChina Department of Neurology The First Affiliated Hospital of Chongqing Medical UniversityChongqing Key Laboratory of NeurologyChongqingChina

Alzheimer's disease is a common neurodegenerative disorder in older *** its prevalence,its pathogenesis remains unclea *** addition to the most widely accepted causes,which in clude excessive amyloid-beta aggregation,tau hyperphosphorylation,and deficiency of the neurotransmitter acetylcholine,numerous studies have shown that the dopaminergic system is also closely associated with the occurrence and development of this *** is a crucial catecholaminergic neurotransmitter in the human ***-associated treatments,such as drugs that target dopamine receptor D and dopamine analogs,can improve cognitive function and alleviate psychiatric symptoms as well as ameliorate other clinical *** r,therapeutics targeting the dopaminergic system are associated with various adverse reactions,such as addiction and exacerbation of cognitive *** review summarizes the role of the dopaminergic system in the pathology of Alzheimer's disease,focusing on currently available dopamine-based therapies for this disorder and the common side effects associated with dopamine-related *** aim of this review is to provide insights into the potential connections between the dopaminergic system and Alzheimer's disease,thus helping to clarify the mechanisms underlying the condition and exploring more effective therapeutic options.

关键词： adverse drug reaction Alzheimer's disease catecholamine dopamine receptor dopamine receptor heterodimers dopaminergic system neurodegenerative disease neurotransmitter signaling pathways traditional Chinese medicine treatment

Computed tomography enterography-based radiomics for assessing mucosal healing in patients with small bowel Crohn's disease

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World Journal of Gastroenterology 2025年第3期31卷 62-72页

作者： Hao Ding yuan-yuan Fang Wen-Jie Fan Chen-Yu Zhang Shao-Fei Wang Jing Hu Wei Han Qiao Mei Department of Gastroenterology The First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina Department of Radiation Oncology The First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina Department of Gastroenterology Suzhou First People's HospitalSuzhou 234099Anhui ProvinceChina

BACKGROUND Mucosal healing(MH)is the major therapeutic target for Crohn's disease(CD).As the most commonly involved intestinal segment,small bowel(SB)assessment is crucial for CD ***,it poses a significant challenge due to its limited accessibility through conventional endoscopic *** To establish a noninvasive radiomic model based on computed tomography enterography(CTE)for MH assessment in SBCD *** Seventy-three patients diagnosed with SBCD were included and divided into a training cohort(n=55)and a test cohort(n=18).Radiomic features were obtained from CTE images to establish a radiomic *** demographics were analysed to establish a clinical model.A radiomic-clinical nomogram was constructed by combining significant clinical and radiomic *** diagnostic efficacy and clinical benefit were evaluated via receiver operating characteristic(ROC)curve analysis and decision curve analysis(DCA),*** Of the 73 patients enrolled,25 patients achieved *** radiomic-clinical nomogram had an area under the ROC curve of 0.961(95%confidence interval:0.886-1.000)in the training cohort and 0.958(0.877-1.000)in the test cohort and provided superior clinical benefit to either the clinical or radiomic models alone,as demonstrated by *** These results indicate that the CTE-based radiomic-clinical nomogram is a promising imaging biomarker for MH and serves as a potential noninvasive alternative to enteroscopy for MH assessment in SBCD patients.

关键词： Crohn’s disease Computed tomography enterography Mucosal healing Nomogram Radiomics