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基于5 μm厚向列相液晶的高效圆极化相控阵系统的设计、校准和实验验证 Article

Xin Yu Wu,Fengshuo Wan,Hongyuan Feng,Shichao Jin,Chong Guo,Yu Wei,Dunge Liu,Yuqian Yang,Longzhu Cai,Zhi Hao Jiang,Wei Hong

《工程(英文)》 2024年 第32卷 第1期   页码 70-82 doi: 10.1016/j.eng.2023.08.013

摘要:

This paper presents a systematic investigation and demonstration of a K-band circularly polarized liquid-crystal-based phased array (LCPA), including the design, over-the-air (OTA) in-array calibration, and experimental validation. The LCPA contains 16 phase-shifting radiating channels, each consisting of a circularly polarized stacked patch antenna and a liquid-crystal-based phase shifter (LCPS) based on a loaded differential line structure. Thanks to its slow-wave properties, the LCPS exhibits a maximum phase-shifting range of more than 360° with a figure of merit of 78.3°·dB−1 based on a liquid crystal layer with a thickness of only 5 μm. Furthermore, an automatic OTA calibration based on a state ergodic method is proposed, which enables the extraction of the phase–voltage curve of every individual LCPA channel. The proposed LCPA is manufactured and characterized with a total profile of only 1.76 mm, experimentally demonstrating a scanned circularly polarized beam from −40° to +40° with a measured peak gain of 12.5 dBic and a scanning loss of less than 2.5 dB. The bandwidth of the LCPA, which satisfies the requirements of port reflection (|S11|) < −15 dB, an axial ratio (AR) < 3 dB, beam squinting < 3°, and a gain variation < 2.2 dB, spans from 25.5 to 26.0 GHz. The total efficiency is about 34%, which represents a new state of the art. The use of the demonstrated low-profile LCPA to support circularly polarized scanning beams, along with the systematic design and calibration methodology, holds potential promise for a variety of millimeter-wave applications.

关键词: Circularly polarized     Liquid crystal     Liquid-crystal-based phased array (LCPA)     Phase shifter     Over-the-air (OTA) calibration    

多入多出系统的空口测量 Review Articles

李俊1,2,漆一宏3,范峻4

《信息与电子工程前沿(英文)》 2021年 第22卷 第8期   页码 1046-1058 doi: 10.1631/FITEE.2000230

摘要: 空中测试(OTA)是评估无线设备中收发性能的一种行业标准做法。对于第五代(5G)和更高集成度的无线系统,OTA测试可能是能够准确测量收发器性能的唯一可靠方法,可用于设备认证,并为设计验证和优化提供反馈。本文概述了评估OTA MIMO性能的3种主要方法,即多探头法(MPAC)、混响室加信道模拟器(RC+CE)方法和辐射两步法(RTS),目的是为5G及未来无线系统的无线性能测试提供有用指导。

关键词: 空中(OTA)测试;无线性能测试;第五代(5G)及超5代;多入多出(MIMO);多探头法(MPAC);辐射两步法(RTS);混响室加通道模拟器法(RC+CE)    

用于毫米波性能空口测试的空间衰落信道重现技术:概念和实验验证

范伟1,Lassi HENTILÄ2,Pekka KYÖSTI2,3

《信息与电子工程前沿(英文)》 2021年 第22卷 第4期   页码 548-559 doi: 10.1631/FITEE.2000484

摘要: 极具吸引力和应用前景的毫米波空口(OTA)辐射测试方法是在实验室条件下模拟实际的传播条件对毫米波设备进行虚拟现场测试。本文首先讨论了在衰落信道条件下毫米波5G NR空口测量的需求和挑战。

关键词: 空间信道模型;空口测试;无线线缆;多探头电波暗室;FR2验证    

Calibration of catalyst temperature in automotive engines over coldstart operation in the presence of

Nasser L. AZAD,Ahmad MOZAFFARI

《机械工程前沿(英文)》 2015年 第10卷 第4期   页码 405-412 doi: 10.1007/s11465-015-0354-x

摘要:

The main scope of the current study is to develop a systematic stochastic model to capture the undesired uncertainty and random noises on the key parameters affecting the catalyst temperature over the coldstart operation of automotive engine systems. In the recent years, a number of articles have been published which aim at the modeling and analysis of automotive engines’ behavior during coldstart operations by using regression modeling methods. Regarding highly nonlinear and uncertain nature of the coldstart operation, calibration of the engine system’s variables, for instance the catalyst temperature, is deemed to be an intricate task, and it is unlikely to develop an exact physics-based nonlinear model. This encourages automotive engineers to take advantage of knowledge-based modeling tools and regression approaches. However, there exist rare reports which propose an efficient tool for coping with the uncertainty associated with the collected database. Here, the authors introduce a random noise to experimentally derived data and simulate an uncertain database as a representative of the engine system’s behavior over coldstart operations. Then, by using a Gaussian process regression machine (GPRM), a reliable model is used for the sake of analysis of the engine’s behavior. The simulation results attest the efficacy of GPRM for the considered case study. The research outcomes confirm that it is possible to develop a practical calibration tool which can be reliably used for modeling the catalyst temperature.

关键词: automotive engine     calibration     coldstart operation     Gaussian process regression machine (GPRM)     uncertainty and random noises    

Catalytic wet air oxidation of phenol, nitrobenzene and aniline over the multi-walled carbon nanotubes

Shaoxia YANG,Yu SUN,Hongwei YANG,Jiafeng WAN

《环境科学与工程前沿(英文)》 2015年 第9卷 第3期   页码 436-443 doi: 10.1007/s11783-014-0681-x

摘要: Wet air oxidation (WAO) is one of effective technologies to eliminate hazardous, toxic and highly concentrated organic compounds in the wastewater. In the paper, multi-walled carbon nanotubes (MWCNTs), functionalized by O , were used as catalysts in the absence of any metals to investigate the catalytic activity in the catalytic wet air oxidation (CWAO) of phenol, nitrobenzene (NB) and aniline at the mild operating conditions (reaction temperature of 155°C and total pressure of 2.5 MPa) in a batch reactor. The MWCNTs were characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM), gas adsorption measurements (BET), fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). The functionalized MWCNTs showed good catalytic performance. In the CWAO of phenol over the functionalized MWCNTs, total phenol removal was obtained after 90 min run, and the reaction apparent activation energy was ca. 40 kJ·mol . The NB was not removed in the CWAO of single NB, while ca. 97% NB removal was obtained and 40% NB removal was attributed to the catalytic activity after 180 min run in the presence of phenol. Ca. 49% aniline conversion was achieved after 120 min run in the CWAO of aniline.

关键词: catalytic wet air oxidation (CWAO)     carbon nanotubes (CNTs)     phenol     nitrobenzene     aniline    

Wastewater treatment by catalytic wet air oxidation process over Al-Fe pillared clays synthesized using

Halima Sassi, Gwendoline Lafaye, Hédi Ben Amor, Abdelaziz Gannouni, Mohamed Razak Jeday, Jacques Barbier-Jr

《环境科学与工程前沿(英文)》 2018年 第12卷 第1期 doi: 10.1007/s11783-017-0971-1

摘要: Microwave irradiation has been used to prepare Al, Fe-pillared clays from a natural Tunisian smectite from the El Hicha deposit (province of Gabes). Chemical analysis, XRD spectra and surface properties evidenced the success of pillaring process. The obtained solids present higher surface area and pore volume than conventionally prepared Al-Fe pillared clays. The main advantages of the microwave methodology are the considerable reduction of the synthesis time and the consumption of water. The microwave-derived Al-Fe pillared clays have been tested for catalytic wet air oxidation (CWAO) of phenol in a stirred tank at 160°C and 20 bar of pure oxygen pressure. These materials are efficient for CWAO of phenol and are highly stable despite the severe operating conditions (acidic media, high pressure, high temperature). The catalyst deactivation was also significantly hindered when compared to conventionally prepared clays. Al-Fe pillared clays prepared by microwave methodology are promising as catalysts for CWAO industrial water treatment.

关键词: Water     Catalytic wet air oxidation     Pillared clays     Microwave     Phenol    

海洋二号扫描微波辐射计冷空定标和地球物理参数反演研究

周武,林明森,李延民,王振占,黄磊

《中国工程科学》 2013年 第15卷 第7期   页码 75-80

摘要:

本文研究了海洋二号(HY-2A)扫描微波辐射计冷空定标方法和数据反演算法。针对HY-2A扫描微波辐射计对地观测和定标扫描的设计原理和观测几何,基于微波辐射计的对地观测数据修正进入冷空反射器的地球信号,建立地面观测亮温的冷空反射器权重系数矩阵修正冷空观测信号;基于海面温度、海面风速、水汽含量和云液态含量的微波辐射计辐射传输模型,计算HY-2A扫描微波辐射计不同条件下的各频率极化方式下的理论亮温,建立线性回归模型,拟合不同地球物理参数的反演系数,采用多元线性回归算法反演HY-2A微波扫描辐射计地球物理参数,对比国外成熟微波辐射计数据,得到产品精度。

关键词: 扫描微波辐射计     多元线性回归     星星交叉     冷空定标    

青藏高原多圈层相互作用观测工程及其应用

马耀明

《中国工程科学》 2012年 第14卷 第9期   页码 28-34

摘要:

青藏高原作为地球的第三极,是“水—冰—气—生”多圈层体现最全,且相互作用最强烈的地区。高原强大的动力和热力作用显著地影响着东亚气候格局、亚洲季风进程和北半球大气环流。全球气候变化不仅影响到青藏高原本身的水圈与冰冻圈过程,改变青藏高原内部的生态系统与环境,影响该地区社会经济发展与人民生存条件,而且通过大气环流与水循环过程直接影响到东亚及周边国家的用水安全和自然灾害防护。正确认识青藏高原复杂地表多圈层相互作用规律的一条有效途径是在各种不同的下垫面上建立多圈层相互作用综合观测站(点)。在中国科学院和国家相关部门的支持下,过去的7年中,中国科学院青藏高原研究所与其他相关单位一道正在整个青藏高原面上逐步建立“青藏高原观测研究平台”以研究该地区复杂地表的多圈层相互作用规律。首先具体介绍中国科学院青藏高原研究所在高原上已经建立的5个综合观测研究站,然后介绍利用各个站点观测资料分析得到的多圈层相互作用(主要是地气相互作用)的研究结果,最后提出了青藏高原多圈层相互作用观测试验研究所面临的难题和可能的解决办法。

关键词: 青藏高原     多圈层相互作用过程     观测结果    

Development of a novel hand−eye calibration for intuitive control of minimally invasive surgical robot

《机械工程前沿(英文)》 2022年 第17卷 第3期 doi: 10.1007/s11465-022-0698-y

摘要: Robotic-assisted surgical system has introduced a powerful platform through dexterous instrument and hand−eye coordination intuitive control. The knowledge of laparoscopic vision is a crucial piece of information for robot-assisted minimally invasive surgery focusing on improved surgical outcomes. Obtaining the transformation with respect to the laparoscope and robot slave arm frames using hand−eye calibration is essential, which is a key component for developing intuitive control algorithm. We proposed a novel two-step modified dual quaternion for hand−eye calibration in this study. The dual quaternion was exploited to solve the hand−eye calibration simultaneously and powered by an iteratively separate solution. The obtained hand−eye calibration result was applied to the intuitive control by using the hand−eye coordination criterion. Promising simulations and experimental studies were conducted to evaluate the proposed method on our surgical robot system. We extensively compared the proposed method with state-of-the-art methods. Results demonstrate this method can improve the calibration accuracy. The effectiveness of the intuitive control algorithm was quantitatively evaluated, and an improved hand−eye calibration method was developed. The relationship between laparoscope and robot kinematics can be established for intuitive control.

关键词: minimally invasive surgery     hand−eye calibration     intuitive control     surgical robot     dual quaternion    

不确定二阶非线性多智能体系统时变编队跟踪控制 None

Jian-wen XU, Kaoru OTA, Mian-xiong DONG, An-feng LIU, Qiang LI

《信息与电子工程前沿(英文)》 2018年 第19卷 第12期   页码 1546-1557 doi: 10.1631/FITEE.1800519

摘要: 研究了含未知非线性动态和外界干扰的二阶多智能体系统时变编队跟踪控制问题。在所考虑的时变编队跟踪控制中,每个跟踪者在完成预设编队的同时,需要跟踪领导者轨迹。将未知非线性动态和外界干扰视为每个多智能体的扩张状态,并设计扩张状态观测器对扩张状态进行在线观测。在此基础上,提出基于扩张状态观测器的时变编队跟踪控制协议。理论分析表明,所设计的时变编队跟踪控制协议能够保证观测器观测误差和多智能体系统时变编队跟踪误差收敛至任意小。最后,将所设计的时变编队跟踪协议应用于无人机目标合围问题,验证了该方法的有效性。

关键词: 多智能体系统;时变编队;编队跟踪;非线性动态;扩张状态观测器    

一种机械臂在线标定装置开发 Research Article

万梓威1,2,周春琳1,3,张昊天4,吴俊1

《信息与电子工程前沿(英文)》 2023年 第24卷 第2期   页码 217-230 doi: 10.1631/FITEE.2200172

摘要:

提出一种名为MultiCal的新型接触式三维测量装置,可用于机械臂的现场标定和在线精度测量,具有使用方便、成本低(低于5000美元)、性能可靠等优点。该设备可灵活地设置在机械臂的工作环境中进行微米级精度三维测量。在标定过程中,通过一个三维位移测量装置,让机械臂的工具中心点运动至一个固定点,之后再绕该点旋转运动至不同姿态角并测量各关节角度(单点约束测量)。然后采用一个创新设计的夹具,将三维位移测量装置精确地安装在该夹具的不同工位上,并重复上述测量过程,从而实现多点约束测量。夹具上不同工位的相对位置在标定前已被精确测量,并作为标定的先验信息,以提高标定的精度与鲁棒性。理论分析表明,在相同水平的测量误差下,MultiCal的理论标定精度与传统的非接触式三维或六维测量设备(如激光跟踪器)相比降低10%—20%。而在Staubli TX90机械臂上进行的实际标定实验结果表明,MultiCal实际标定精度仅比带激光扫描仪的测量臂低7%—14%,时间效率比六维双目视觉测量系统低21%—30%,标定后的机械臂的最大和平均绝对定位误差分别为0.831 mm和0.339 mm。

关键词: 标定装置;运动学标定;现场标定;绝对定位精度    

Remote calibration system for frequency based on in-place benchmark

Xiaobin HONG, Guixiong LIU, Zhuokui WU, Xipeng DU,

《机械工程前沿(英文)》 2010年 第5卷 第3期   页码 316-321 doi: 10.1007/s11465-010-0021-1

摘要: According to the deficiencies of remote calibration mode based on material object reference, a new model of a remote calibration system for frequency based on in-place benchmark is introduced, which is made of a calibration subsystem on the spot and a remote management subsystem. The key technology of some key problems for the remote calibration system is particularly discussed, including the time and frequency benchmark receiving module based on global positioning system (GPS), frequency comparison based on a phase method, frequency division based on dual high-frequency phase locked loop (PLL), and remote calibration based on the web. The results show that the system possesses some characteristics, such as high precision, good versatility, and no limitation of time and place.

关键词: remote calibration     in-place benchmark     frequency comparison     global position system (GPS)    

Ultrasound-guided prostate percutaneous intervention robot system and calibration by informative particle

《机械工程前沿(英文)》 2022年 第17卷 第1期   页码 3-3 doi: 10.1007/s11465-021-0659-x

摘要: Applying a robot system in ultrasound-guided percutaneous intervention is an effective approach for prostate cancer diagnosis and treatment. The limited space for robot manipulation restricts structure volume and motion. In this paper, an 8-degree-of-freedom robot system is proposed for ultrasound probe manipulation, needle positioning, and needle insertion. A novel parallel structure is employed in the robot system for space saving, structural rigidity, and collision avoidance. The particle swarm optimization method based on informative value is proposed for kinematic parameter identification to calibrate the parallel structure accurately. The method identifies parameters in the modified kinematic model stepwise according to parameter discernibility. Verification experiments prove that the robot system can realize motions needed in targeting. By applying the calibration method, a reasonable, reliable forward kinematic model is built, and the average errors can be limited to 0.963 and 1.846 mm for insertion point and target point, respectively.

关键词: ultrasound image guidance     prostate percutaneous intervention     parallel robot     kinematics identification     particle swarm optimization     informative value    

Edge detection of steel plates at high temperature using image measurement

Qiong Zhou, Qi An

《机械工程前沿(英文)》 2009年 第4卷 第1期   页码 77-82 doi: 10.1007/s11465-009-0013-1

摘要: An edge detection method for the measurement of steel plate’s thermal expansion is proposed in this paper, where the shrinkage of a steel plate is measured when temperature drops. First, images are picked up by an imaging system; a method of regional edge detection based on grayscales’ sudden change is then applied to detect the edges of the steel plate; finally, pixel coordinates of the edge position are transformed to physical coordinates through calibration parameters. The experiment shows that the real-time, high precision, and non-contact measurement of the steel plate’s edge position under high temperature can be realized using the imaging measurement method established in this paper.

关键词: thermal expansion     image measurement     edge detection     image calibration    

Design and calibration of a new high-definition three-dimensional laparoscopic system

Jia TANG,Li-qiang WANG,Bo YUAN,Hong JIANG,Qi-ming ZHU

《信息与电子工程前沿(英文)》 2015年 第16卷 第1期   页码 79-84 doi: 10.1631/FITEE.1400149

摘要: We present a high-definition (HD) 3D laparoscopic system including a dual channel optical system, two cameras, a camera control unit (CCU), and an HD 3D monitor. This laparoscopic system is capable of outputting dual high-definition videos and providing vivid 3D images. A modified pinhole camera model is used for camera calibration and a new method of depth measurement to improve precision. The average error of depth measurement measured by experiment (about 1.13 mm) was small in proportion to the large range in distance of the system (10-150 mm). The new method is applicable to any calibrated binocular vision system.

关键词: Dual optical channels     Three dimensional     Camera calibration     Pinhole model     Depth measurement     Laparoscopic system    

标题 作者 时间 类型 操作

基于5 μm厚向列相液晶的高效圆极化相控阵系统的设计、校准和实验验证

Xin Yu Wu,Fengshuo Wan,Hongyuan Feng,Shichao Jin,Chong Guo,Yu Wei,Dunge Liu,Yuqian Yang,Longzhu Cai,Zhi Hao Jiang,Wei Hong

期刊论文

多入多出系统的空口测量

李俊1,2,漆一宏3,范峻4

期刊论文

用于毫米波性能空口测试的空间衰落信道重现技术:概念和实验验证

范伟1,Lassi HENTILÄ2,Pekka KYÖSTI2,3

期刊论文

Calibration of catalyst temperature in automotive engines over coldstart operation in the presence of

Nasser L. AZAD,Ahmad MOZAFFARI

期刊论文

Catalytic wet air oxidation of phenol, nitrobenzene and aniline over the multi-walled carbon nanotubes

Shaoxia YANG,Yu SUN,Hongwei YANG,Jiafeng WAN

期刊论文

Wastewater treatment by catalytic wet air oxidation process over Al-Fe pillared clays synthesized using

Halima Sassi, Gwendoline Lafaye, Hédi Ben Amor, Abdelaziz Gannouni, Mohamed Razak Jeday, Jacques Barbier-Jr

期刊论文

海洋二号扫描微波辐射计冷空定标和地球物理参数反演研究

周武,林明森,李延民,王振占,黄磊

期刊论文

青藏高原多圈层相互作用观测工程及其应用

马耀明

期刊论文

Development of a novel hand−eye calibration for intuitive control of minimally invasive surgical robot

期刊论文

不确定二阶非线性多智能体系统时变编队跟踪控制

Jian-wen XU, Kaoru OTA, Mian-xiong DONG, An-feng LIU, Qiang LI

期刊论文

一种机械臂在线标定装置开发

万梓威1,2,周春琳1,3,张昊天4,吴俊1

期刊论文

Remote calibration system for frequency based on in-place benchmark

Xiaobin HONG, Guixiong LIU, Zhuokui WU, Xipeng DU,

期刊论文

Ultrasound-guided prostate percutaneous intervention robot system and calibration by informative particle

期刊论文

Edge detection of steel plates at high temperature using image measurement

Qiong Zhou, Qi An

期刊论文

Design and calibration of a new high-definition three-dimensional laparoscopic system

Jia TANG,Li-qiang WANG,Bo YUAN,Hong JIANG,Qi-ming ZHU

期刊论文