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Chinese Journal of Electronics 2024年第6期33卷 1468-1477页

作者： Jiwei LIAN Chun GENG Xue LU dazhi ding School of Microelectronics(School of Integrated Circuits) Nanjing University of Science and Technology State Key Laboratory of Millimeter Waves Southeast University Qian Xuesen College Nanjing University of Science and Technology

A wideband circularly polarized(CP) aperture-coupled metasurface antenna operating at millimeterwave frequency spectrum in substrate-integrated waveguide(SIW) technology is proposed. The proposed metasurface antenna is composed of two substrates. The first substrate contains an end-shorted SIW section with a slot *** introduced metasurface is printed on the top of the second substrate. The metasurface is comprised of 3 × 3 unit cells, each of which contains two interconnected patches and two parasitic patches. The working mechanism of the proposed metasurface antenna is illustrated in details. The proposed metasurface antenna has wide impedance bandwidth and axial ratio(AR) bandwidth, which are 66.7% and 40%, respectively. Using the proposed metasurface antenna, a 4 × 4 CP metasurface antenna array with an impedance bandwidth of 24%, an AR bandwidth of 30%, and a peak gain of 18.7 dBic in simulation is developed in this paper for millimeter-wave applications.

关键词： Antenna measurements Parametric study Millimeter wave technology Metasurfaces Aperture antennas Impedance Broadband antennas Substrates Wideband Antenna arrays

Characteristic Mode Design of Dual-Band Reconfigurable Frequency Selective Surface

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Chinese Journal of Electronics 2022年第6期31卷 1129-1137页

作者： NING Zihao LI Mengmeng ding dazhi AI Xia LIU Jiaqi Department of Communication Engineering Nanjing University of Science and Technology National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics

In this paper, a characteristic mode design of dual-band reconfigurable frequency selective surface(RFSS) with transmission/reflection band is presented. Through the visualization of modal behavior, the theory of characteristic modes(TCM) is used to guide design from a physical perspective. At first, the dominant modes of two basic structures that have a major impact on reflection are clarified by observing the modal *** appropriate combination of the two structures forms an initial element with bandpass properties. Then, the positive-intrinsic-negative(PIN) diode is placed in the middle of the microstrip line and as the state shifts from ON to OFF, the dominant mode resonant frequency of the microstrip line shifts upward. Such a feature can be used to design the transmission/reflection RFSS. Experimentally, a dual-band RFSS operating at 8.8 GHz and 10.4 GHz is designed and fabricated. The measured results that agree with the full-wave simulation validate the proposed TCM-based design.

关键词： dual-band reconfigurable frequency selective surface dual-band RFSS positive-intrinsic-negative diode theory of characteristic modes characteristic mode design full-wave simulation transmission band p-i-n diodes modal behavior visualization bandpass properties microstrip lines microstrip line dominant mode resonant frequency PIN diode microwave filters frequency selective surfaces TCM-based design reflection band transmission RFSS microwave diodes band-pass filters microstrip filters reflection RFSS

Characteristic Mode Analysis for Thin Dielectric Sheets with Alternative Surface Integral Equation

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Chinese Journal of Electronics 2022年第6期31卷 1181-1188页

作者： JIA Chunlai HE Zi ding dazhi GUAN Ling AI Xia LIU Jiaqi CHEN Xuewen Department of Communication Engineering Nanjing University of Science and Technology Science and Technology on Electromagnetic Scattering Laboratory Beijing Institute of Environmental Features National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics School of Physics and Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology

When the dielectric sheet is electrically thin in the normal direction, the conventional volume integral equation(VIE) can be approximately simplified to the surface one. On this basis, a novel surface integral equation-based formulation is presented for analyzing characteristic mode(CM) of thin dielectric sheets. The resultant CMs are expressed with tangential and normal components of electric volume currents, which are more intuitive than the conventional VIE-based one. Due to the application of volume equivalence principle, the proposed formulation is immune to non-physical modes. The CMs of typical thin dielectric bodies, including the dielectric substrate and radome, are analyzed to show that the proposed formulation is computationally efficient with encouraging accuracy.

关键词： normal components alternative surface integral equation thin dielectric sheets normal direction electric volume currents dielectric sheet radome radomes dielectric bodies surface integral equation-based formulation volume equivalence principle thin dielectric bodies tangential components nonphysical modes electromagnetic wave scattering conventional volume integral equation integral equations characteristic mode analysis dielectric substrate

Compact millimeter-wave air-filled substrate-integrated waveguide crossover employing homogeneous cylindrical lens

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Frontiers of Information Technology & Electronic Engineering 2023年第9期24卷 1366-1374页

作者： Chun GENG Jiwei LIAN dazhi ding Qian Xuesen College Nanjing University of Science and TechnologyNanjing 210094China School of Microelectronics(School of Integrated Circuits) Nanjing University of Science and TechnologyNanjing 210094China State Key Laboratory of Millimeter Waves Southeast UniversityNanjing 210096China

We propose a new method to design crossovers by employing an embedded homogeneous cylindrical lens(HCL).Compared with traditional crossover designs,this strategy introduces an HCL within the air-filled substrate-integrated waveguide(SIW)crossover cavity to direct the incident waves in the desired *** to ray-tracing analysis,the added HCL can efficiently concentrate the electromagnetic wave propagating from the input to the output without increasing the fabrication complexity or footprint.

关键词： waveguide millimeter crossover

Forskolin Modulates the Inhibitory Effect of C-Type Natriuretic Peptide on Hypoxia-Induced Atrial Dynamics and Hypoxia Inducible Factor 1 Alpha Activity

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Journal of Biosciences and Medicines 2017年第1期5卷 1-10页

作者： Chengming Guan Yanan Jia Chaochao Bian Bo Zhang dazhi ding Xun Cui Institue of Clinical Medicine Yanbian University Yanji China Department of Physiology School of Medicine Yanbian University Yanji China Key Laboratory of Organism Functional Factors of the Changbai Mountain Ministry of Education Yanbian University Yanji China Cellular Function Research Center Yanbian University Yanji China

Our study investigated effects of C-type natriuretic peptide (CNP) on atrial dynamics and hypoxia inducible factor 1 alpha (HIF-1α) activity in perfused beating rat atria, under hypoxic conditions. Hypoxia significantly increased the levels of HIF-1α, concomitant with decreased trial dynamics. CNP (0.1 μmol/L) further decreased atrial dynamics under hypoxia and suppressed hypoxia-induced stimulation of HIF-1α expression. An adenylylcyclase (AC) activator, forskolin (0.1 μmol/L), significantly up-regulated atrial phosphodiesterase subtype 3A (PDE 3A) protein without affecting hypoxia-induced dynamics. In the presence of forskolin, the inhibitory effects of CNP on hypoxia-induced atrial dynamics and HIF-1α levels were significantly attenuated. Forskolin also prevented hypoxia-induced downregulation of PDE3A protein. These findings suggested that CNP inhibited atrial dynamics and HIF-1α activity in the isolated perfused beating rat atria under hypoxic conditions. Furthermore, both effects were modulated by the AC activator forskolin, through activation of CNP-PDE 3A signaling.

关键词： C-Type Natriuretic Peptide Hypoxia Inducible Factor-1α Phosphodiesterase Adenylyl Cyclase Forskolin

Endogenous Endothelin-1 Regulates Hypoxia-Induced Atrial Natriuretic Peptide Secretion by Activating the MAPK/ERK and PI3K/Akt Signaling Pathways in Isolated Beating Rabbit Atria

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Journal of Biosciences and Medicines 2016年第1期4卷 45-53页

作者： Chaochao Bian dazhi ding Honghua Jin Liping Liu Lan Hong Bairi Cui Xun Cui Department of Physiology School of Medicine Yanbian University Yanji China Institue of Clinical Medicine Yanbian University Yanji China Key Laboratory of Organism Functional Factors of the Changbai Mountain Ministry of Education Yanbian University Yanji China Cellular Function Research Center Yanbian University Yanji China

The present study investigated a possible mechanism for endogenous endothelin-1 (ET-1) regulation of atrial natriuretic peptide (ANP) secretion in isolated perfused acute hypoxic rabbit atria. Acute hypoxia significantly enhanced the release of ET-1 and the expression of the ET receptor (ETR) type A and B (ETRA and ETRB) in atrial tissues, with a concomitant increase in ANP secretion. The ETRA or ETRB antagonist, BQ123 (0.3 μmol/L) or BQ788 (0.3 μmol/L), respectively attenuated hypoxia-induced ANP secretion. Both antagonists significantly attenuated the levels of hypoxiainduced atrial phosphorylated (p)-extracellular signal-regulated kinase (ERK) and p-protein kinase B (Akt). The ERK and Akt inhibitors, PD098059 (30 μmol/L) and LY294002 (30 μmol/L), respectively mimicked the effect of the ETR antagonists. These results demonstrated that acute hypoxia- mediated atrial ET-1 regulated ANP secretion through ETR and the subsequent mitogenactivated protein kinase (MAPK)/ERK and ETR-phosphatidylinositol-3-kinase (PI3K)/Akt signaling pathways. These pathways may mediate atrial endocrine functions under hypoxic conditions.

关键词： Hypoxia Endothelin-1 ET Receptor Atrial Natriuretic Peptide Signaling Pathway

基于新型混合场积分方程的半空间三维均匀介质目标电磁散射分析

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计算物理 2010年第1期27卷 89-94页

作者：胡云琴安宁丁大志陈如山南京理工大学电子工程与光电技术学院江苏南京210094

利用介质半空间格林函数,将一种混合场积分方程(JMCFIE)推广应用到有耗半空间的均匀介质的散射分析中,以减少离散矩阵方程迭代求解时所需的迭代步数,提高矩量法(MoM)对半空间介质目标散射分析的求解效率.数值算例验证了方法的准确性和... 详细信息

利用介质半空间格林函数,将一种混合场积分方程(JMCFIE)推广应用到有耗半空间的均匀介质的散射分析中,以减少离散矩阵方程迭代求解时所需的迭代步数,提高矩量法(MoM)对半空间介质目标散射分析的求解效率.数值算例验证了方法的准确性和有效性.

关键词：有耗半空间均匀介质散射矩量法表面积分方程

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宽带宽角扫描共形阵列高效稀布优化技术

科学通报 2023年第25期68卷 3244-3246页

作者：顾鹏飞何姿樊振宏丁大志南京理工大学微电子学院南京210094

雷达系统作为战场上的眼睛,被大量集成在导弹、卫星、舰艇等军用设施上,实现对陆海空天全方位的防御.天线作为雷达收发信息的关键部件,希望增益高、带宽宽、体积小.而且,为了不打破载体平台气动性能,往往希望它能与载体表面贴合.然而,... 详细信息

雷达系统作为战场上的眼睛,被大量集成在导弹、卫星、舰艇等军用设施上,实现对陆海空天全方位的防御.天线作为雷达收发信息的关键部件,希望增益高、带宽宽、体积小.而且,为了不打破载体平台气动性能,往往希望它能与载体表面贴合.然而,伴随着系统功能的日益强大,天线数目和复杂程度也随之增加.受到平台空间载荷的限制,如何利用更少的阵元数目实现阵面最优化布局成为阵列设计中需要解决的关键问题[1].为此,亟须开展高辐射效率、超宽带、低剖面曲面共形稀布阵列研究.

关键词：阵元数目超宽带雷达系统低剖面阵列设计稀布阵列阵面载体平台

小切口切开复位与经皮空心加压螺丝钉内固定治疗内踝骨折的效果对比

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中外医学研究 2024年第33期22卷 9-12页

作者：丁大志南通市通州区人民医院江苏南通226300

目的:比较小切口切开复位与经皮空心加压螺丝钉内固定治疗内踝骨折的效果。方法:选取2019年1月—2023年1月南通市通州区人民医院收治的84例内踝骨折患者作为研究对象,采用随机数表法随机分为切开组和闭合组,每组各42例。切开组行内踝小... 详细信息

目的:比较小切口切开复位与经皮空心加压螺丝钉内固定治疗内踝骨折的效果。方法:选取2019年1月—2023年1月南通市通州区人民医院收治的84例内踝骨折患者作为研究对象,采用随机数表法随机分为切开组和闭合组,每组各42例。切开组行内踝小切口切开复位术,闭合组行经皮微创空心钉内固定术。比较两组的术中出血量、手术时间、骨痂形成时间、骨折愈合时间、肿痛消失时间、术后完全负重时间以及术后并发症情况和关节功能评分。结果:闭合组的手术时间、术中出血量均低于切开组,差异有统计学意义(P0.05);闭合组的骨折愈合时间、肿痛消失时间以及完全负重时间均短于切开组,差异有统计学意义(P<0.05);闭合组术后并发症总发生率低于切开组,差异有统计学意义(P<0.05);闭合组的优良率高于对照组,差异有统计学意义(P<0.05)。结论:与传统的小切口切开复位法比较,经皮空心加压螺丝钉内固定术治疗踝关节骨折具有手术创伤小、恢复快、并发症少等优点。

关键词：小切口切开复位内固定内踝骨折

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典型植被的高效电磁全波分析方法研究

系统工程与电子技术 2021年第10期43卷 2725-2732页

作者：何姿操龙潜丁大志樊振宏陈如山南京理工大学电子工程与光电技术学院江苏南京210094

(地物的电磁散射特性一直以来在遥感、探测、反隐身等领域具有重要的应用价值。由于地物类型繁多且分布不均匀,随着计算场景的扩大,理论模型变的越来越复杂,计算量也会直线上升。在这种情况下,现有计算平台和建模能力不足以模拟并准确... 详细信息

(地物的电磁散射特性一直以来在遥感、探测、反隐身等领域具有重要的应用价值。由于地物类型繁多且分布不均匀,随着计算场景的扩大,理论模型变的越来越复杂,计算量也会直线上升。在这种情况下,现有计算平台和建模能力不足以模拟并准确地得到场景环境较大时典型地物的电磁散射特性,导致理论模型的预测值与实验测量数据相差甚远。因此,急需建立一种高效的全波电磁分析方法,从而能够精确、高效地分析典型地物的电磁散射特性,为实际大型地面场景特性仿真提供模型与理论支撑。)本文建立了求解TDS、介质的混合积分方程,采用周期格林函数技术,实现大场景下典型植被的雷达散射截面积快速计算。

关键词：积分方程方法电磁散射典型地物周期格林函数