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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    

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Dynamic modulation performance of ferroelectric liquid crystal polarization rotators and Mueller matrix

Song ZHANG, Lelun WANG, Anze YI, Honggang GU, Xiuguo CHEN, Hao JIANG, Shiyuan LIU

《机械工程前沿（英文）》 2020年 第15卷 第2期   页码 256-264 doi: 10.1007/s11465-019-0573-7

摘要： A ferroelectric liquid crystal polarization rotator (FLCPR) has been widely used in polarization measurement due to its fast and stable modulation characteristics. The accurate characterization of the modulation performance of FLCPR directly affects the measurement accuracy of the instrument based on liquid crystal modulation. In this study, FLCPR is accurately characterized using a self-developed high-speed Stokes polarimeter. Strong linear and weak circular birefringence are observed during modulation processes, and all the optical parameters of FLCPR are dependent on driving voltage. A dual FLCPR-based Mueller matrix polarimeter is designed on the basis of the Stokes polarimeter. The designed polarimeter combines the advantages of the high modulation frequency of FLCPR and the ultrahigh temporal resolution of the fast polarization measurement system in the Stokes polarimeter. The optimal configuration of the designed polarizer is predicted in accordance with singular value decomposition. A simulated thickness measurement of a 24 nm standard SiO thin film is performed using the optimal configuration. Results show that the relative error in thickness measurement caused by using the unsatisfactory modulation characteristics of FLCPR reaches up to −4.34%. This finding demonstrates the importance of the accurate characterization of FLCPR in developing a Mueller matrix polarizer.

关键词： ferroelectric liquid crystal polarization rotator (FLCPR)     dual liquid crystal Mueller matrix polarizer     design and optimization    

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一种用于多功能相控阵雷达调度的混合遗传粒子群算法 Article

Hao-wei ZHANG, Jun-wei XIE, Wen-long LU, Chuan SHENG, Bin-feng ZONG

《信息与电子工程前沿（英文）》 2017年 第18卷 第11期   页码 1806-1816 doi: 10.1631/FITEE.1601358

摘要： 为解决多功能相控阵雷达的任务调度难题，本文提出了一种融合粒子群算法、遗传算法和启发式交错算法的优化算法。通过混沌理论优化粒子群算法的飞行参数，设计动态惯性权重，并引入遗传算法中的交叉、变异操作，使该算法的计算效率和寻优能力均得到大幅度提高。在智能算法的框架下，提出启发式的交错调度算法可进一步利用任务等待期的时间资源。仿真结果表明，与现有方法相比，本文算法效率更高，鲁棒性更强。

关键词： 相控阵雷达；调度；粒子群算法；遗传算法；脉冲交错    

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Effect of polymer structures on electro-optical properties of polymer stabilized liquid crystal films

WANG Shoulian, HE Jie, ZENG Yu, YAN Bin, WANG Yinghan

《化学科学与工程前沿（英文）》 2008年 第2卷 第3期   页码 265-268 doi: 10.1007/s11705-008-0054-8

摘要： The polymer stabilized liquid crystal (PSLC) film is a relatively novel electro-optical material, which is generally obtained by dissolving a small amount of a bifunctional photoreactive monomer in a low molecular mass liquid crystal. In this paper, the PSLC films were prepared with photoreactive biphenyl methacrylate monomers by photopolymerization induced phase separation. The effects of liquid crystal concentration, curing time, monomer structures and alignment layer on the electro-optical properties of PSLC films were investigated. The results show that the transmittance in the OFF state () increased with the liquid crystal concentration, but the driving voltage decreased. was also influenced by the curing time. Furthermore, when polyimide was used as alignment layer, the films prepared from the bifunctional monomer shows a higher T, while those from the single functional monomer exhibited a deformed electro-optical curve due to the unsteady polymer networks.
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Room temperature liquid metal: its melting point, dominating mechanism and applications

Junheng FU, Chenglin ZHANG, Tianying LIU, Jing LIU

《能源前沿（英文）》 2020年 第14卷 第1期   页码 81-104 doi: 10.1007/s11708-019-0653-8

摘要： The room temperature liquid metal (LM) is recently emerging as a new class of versatile materials with fascinating characteristics mostly originated from its simultaneous metallic and liquid natures. The melting point is a typical parameter to describe the peculiarity of LM, and a pivotal factor to consider concerning its practical applications such as phase change materials (PCMs) and advanced thermal management. Therefore, the theoretical exploration into the melting point of LM is an essential issue, which can be of special value for the design of new LM materials with desired properties. So far, some available strategies such as molecular dynamics (MD) simulation and classical thermodynamic theory have been applied to perform correlative analysis. This paper is primarily dedicated to performing a comprehensive overview regarding typical theoretical strategies on analyzing the melting points. It, then, presents evaluations on several factors like components, pressure, size and supercooling that may be critical for melting processes of liquid metal. After that, it discusses applications associated with the characteristic of low melting points of LM. It is expected that a great many fundamental and practical works are to be conducted in the coming future.

关键词： melting point     liquid metal     crystal     thermodynamics     molecular dynamics    

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基于光谱辐射信息的高温目标图像识别

范学良,程晓舫,许军

《中国工程科学》 2004年 第6卷 第6期   页码 57-62

摘要：

利用光学及辐射度学的基本原理，对成像过程进行理论分析，建立了照明条件下识别视场中高温目标的数学模型，揭示了影响识别效果的各物理因素。通过对这些物理因素进行分析，指出“切割波段”可有效提高信噪比，将高温目标识别出来，并通过液晶光阀予以技术实现。实验结果验证了该方案的可行性及有效性。

关键词： CCD影像     目标识别     辐射信息     液晶光阀    

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LCF behavior and life prediction method of a single crystal nickel-based superalloy at high temperature

Zhihua ZHANG,Huichen YU,Chengli DONG

《机械工程前沿（英文）》 2015年 第10卷 第4期   页码 418-423 doi: 10.1007/s11465-015-0362-x

摘要：

Low cycle fatigue tests were conducted on the single crystal nickel-based superalloy, DD6, with different crystallographic orientations (i.e., [001], [011], and [111]) and strain dwell types (i.e., tensile, compressive, and balanced types) at a certain high temperature. Given the material anisotropy and mean stress, both orientation factor and stress range were introduced to the Smith, Watson, and Topper (SWT) stress model to predict the fatigue life. Experimental results indicated that the fatigue properties of DD6 depend on both crystallographic orientation and loading types. The fatigue life of the tensile, compressive, and balanced strain dwell tests are shorter than those of continuous cycling tests without strain dwell because of the important creep effect. The predicted results of the proposed modified SWT stress method agree well with the experimental data.

关键词： life prediction     single crystal superalloy     low cycle fatigue (LCF)     crystallographic orientation     strain dwell    

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Perspective on gallium-based room temperature liquid metal batteries

《能源前沿（英文）》 2022年 第16卷 第1期   页码 23-48 doi: 10.1007/s11708-022-0815-y

摘要： Recent years have witnessed a rapid development of deformable devices and epidermal electronics that are in urgent request for flexible batteries. The intrinsically soft and ductile conductive electrode materials can offer pivotal hints in extending the lifespan of devices under frequent deformation. Featuring inherent liquidity, metallicity, and biocompatibility, Ga-based room-temperature liquid metals (GBRTLMs) are potential candidates to fulfill the requirement of soft batteries. Herein, to illustrate the glamour of liquid components, high-temperature liquid metal batteries (HTLMBs) are briefly summarized from the aspects of principle, application, advantages, and drawbacks. Then, Ga-based liquid metals as main working electrodes in primary and secondary batteries are reviewed in terms of battery configurations, working mechanisms, and functions. Next, Ga-based liquid metals as auxiliary working electrodes in lithium and nonlithium batteries are also discussed, which work as functional self-healing additives to alleviate the degradation and enhance the durability and capacity of the battery system. After that, Ga-based liquid metals as interconnecting electrodes in multi-scenarios including photovoltaics solar cells, generators, and supercapacitors (SCs) are interpreted, respectively. The summary and perspective of Ga-based liquid metals as diverse battery materials are also focused on. Finally, it was suggested that tremendous endeavors are yet to be made in exploring the innovative battery chemistry, inherent reaction mechanism, and multifunctional integration of Ga-based liquid metal battery systems in the coming future.

关键词： liquid metals     soft electrodes     flexible batteries     deformable energy supply devices     epidermal electronics    

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Assessment of a fuzzy logic based MRAS observer used in a photovoltaic array supplied AC drive

Bhavnesh KUMAR, Yogesh K CHAUHAN, Vivek SHRIVASTAVA

《能源前沿（英文）》 2014年 第8卷 第1期   页码 81-89 doi: 10.1007/s11708-014-0295-9

摘要： In this paper a fuzzy logic (FL) based model reference adaptive system (MRAS) speed observer for high performance AC drives is proposed. The error vector computation is made based on the rotor-flux derived from the reference and the adaptive model of the induction motor. The error signal is processed in the proposed fuzzy logic controller (FLC) for speed adaptation. The drive employs an indirect vector control scheme for achieving a good closed loop speed control. For powering the drive system, a standalone photovoltaic (PV) energy source is used. To extract the maximum power from the PV source, a constant voltage controller (CVC) is also proposed. The complete drive system is modeled in MATLAB/Simulink and the performance is analyzed for different operating conditions.

关键词： induction motor drive     fuzzy logic (FL) control     model reference adaptive system (MRAS)     photovoltaic (PV) array     vector control    

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Systematic screening procedure and innovative energy-saving design for ionic liquid-based extractive

《化学科学与工程前沿（英文）》 2023年 第17卷 第1期   页码 34-45 doi: 10.1007/s11705-022-2234-3

摘要： In the traditional extractive distillation process, organic solvents are often used as entrainers. However, environmental influence and high energy-consumption are significant problems in industrial application. In this study, a systematic screening strategy and innovative energy-saving design for ionic liquid-based extractive distillation process was proposed. The innovative energy-saving design focused on the binary minimum azeotrope mixtures isopropanol and water. Miscibility, environmental impact and physical properties (e.g., melting point and viscosity) of 30 ionic liquids were investigated. 1-Ethyl-3-methyl-imidazolium dicyanamide and 1-butyl-3-methyl-imidazolium dicyanamide were selected as candidate entrainers. Feasibility analysis of these two ionic liquids was further performed via residue curve maps, isovolatility line and temperature profiles. An innovative ionic liquid-based extractive distillation process combining distillation column and stripping column was designed and optimized with the objective function of minimizing the total annualized cost. The results demonstrate that the total annualized cost was reduced by 19.9% with 1-ethyl-3-methyl-imidazolium dicyanamide as the entrainer and by 24.3% with 1-butyl-3-methyl-imidazolium dicyanamide, compared with that of dimethyl sulfoxide. The method proposed in this study is conducive to the green and sustainable development of extractive distillation process.

关键词： ionic liquid     entrainer screening     feasibility analysis     extractive distillation    

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Liquid-based high-temperature receiver technologies for next-generation concentrating solar power: A

《能源前沿（英文）》 2023年 第17卷 第1期   页码 16-42 doi: 10.1007/s11708-023-0866-8

摘要： To reduce the levelized cost of energy for concentrating solar power (CSP), the outlet temperature of the solar receiver needs to be higher than 700 °C in the next-generation CSP. Because of extensive engineering application experience, the liquid-based receiver is an attractive receiver technology for the next-generation CSP. This review is focused on four of the most promising liquid-based receivers, including chloride salts, sodium, lead-bismuth, and tin receivers. The challenges of these receivers and corresponding solutions are comprehensively reviewed and classified. It is concluded that combining salt purification and anti-corrosion receiver materials is promising to tackle the corrosion problems of chloride salts at high temperatures. In addition, reducing energy losses of the receiver from sources and during propagation is the most effective way to improve the receiver efficiency. Moreover, resolving the sodium fire risk and material compatibility issues could promote the potential application of liquid-metal receivers. Furthermore, using multiple heat transfer fluids in one system is also a promising way for the next-generation CSP. For example, the liquid sodium is used as the heat transfer fluid while the molten chloride salt is used as the storage medium. In the end, suggestions for future studies are proposed to bridge the research gaps for > 700 °C liquid-based receivers.

关键词： next-generation concentrating solar power     liquid-based solar receiver     molten salt     liquid metals    

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Harvesting biomechanical energy in the walking by shoe based on liquid metal magnetohydrodynamics

Dan DAI, Jing LIU, Yixin ZHOU

《能源前沿（英文）》 2012年 第6卷 第2期   页码 112-121 doi: 10.1007/s11708-012-0186-x

摘要： A liquid metal magnetohydrodynamics generation system (LMMGS) was proposed and demonstrated in this paper for collecting parasitic power in shoe while walking. Unlike the conventional shoe-mounted human power harvesters that use solid coil and gear mechanism, the proposed system employs liquid metal (Ga In Sn ) as energy carrier, where no moving part is requested in magnetohydrodynamics generators (MHGs). While walking with the LMMGS, the foot alternately presses the two liquid metal pumps (LMPs) which are respectively placed in the front and rear of the sole. As a result, the liquid metal in the LMPs (LMP I and II) is extruded and flows through the MHGs (MHG I and II) in which electricity is produced. For a comparison, three types of LMMGSs (LMMGS A, B and C) were built where all the parts are the same except for the LMPs. Furthermore, performances of these LMMGSs with different volume of injected liquid metal were tested respectively. Experimental results reveal that both the output voltage and power of the LMMGS increase with the volume of injected liquid metal and the size of the LMPs. In addition, a maximum output power of 80 mW is obtained by the LMMGS C with an efficiency of approximately 1.3%. Given its advantages of no side effect, light weight, small size and reliability, The LMMGS is well-suited for powering the wearable and implantable micro/nano device, such as wearable sensors, drug pumps and so on.

关键词： human energy harvesting     liquid metal     wearable magnetohydrodynamics generator     parasitic power in shoe    

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Optimal Su-Do-Ku based interconnection scheme for increased power output from PV array under partial

P. SRINIVASA RAO,P. DINESH,G. SARAVANA ILANGO,C. NAGAMANI

《能源前沿（英文）》 2015年 第9卷 第2期   页码 199-210 doi: 10.1007/s11708-015-0350-1

摘要： Partial shading is a common phenomenon in PV arrays. They drastically reduce the power output because of mismatch losses, which are reliant on the shape of the shade as well as the locations of shaded panels in the array. The power output can be improved by distributing the shade over various rows to maximize the current entering the node. A Su-Do-Ku configuration can be used to rearrange the physical locations of the PV modules in a total cross tied PV array with the electrical connections left unchanged. However, this arrangement increases the length of the wire required to interconnect the panels thus increasing the line losses. In this paper, an improved Su-Do-Ku arrangement that reduces the length of the wire required for the connection is proposed. The system is designed and simulated in a Matlab/Simulink environment for various shading patterns and the efficacies of various arrangements are compared. The results prove that the power output is higher in the proposed improved Su-Do-Ku reconfiguration technique compared to the earlier proposed Su-Do-Ku technique.

关键词： array configuration     mismatch losses     partial shading     line losses     Su-Do-Ku arrangement    

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Rare-earth separation based on the differences of ionic magnetic moment via quasi-liquid strategy

《化学科学与工程前沿（英文）》 2023年 第17卷 第10期   页码 1584-1594 doi: 10.1007/s11705-022-2189-4

摘要： The separation of rare earth elements is particularly difficult due to their similar physicochemical properties. Based on the tiny differences of ionic radius, solvent extraction has been developed as the “mass method” in industry with hundreds of stages, extremely intensive chemical consumption and large capital investments. The differences of the ionic magnetic moment among rare earths are greater than that of ionic radius. Herein, a novel method based on the large ionic magnetic moment differences of rare earth elements was proposed to promote the separation efficiency. Rare earths were firstly dissolved in the ionic liquid, then the ordering degree of them was improved with the Z-bond effect, and finally the magnetic moment differences between paramagnetic and diamagnetic rare earths in quasi-liquid system were enhanced. Taking the separation of Er/Y, Ho/Y and Er/Ho as examples, the results showed that Er(III) and Ho(III) containing ionic liquids had obvious magnetic response, while ionic liquids containing Y(III) had no response. The separation factors of Er/Y and Ho/Y were achieved at 9.0 and 28.82, respectively. Magnetic separation via quasi-liquid system strategy provides a possibility of the novel, green, and efficient method for rare earth separation.

关键词： rare earth element     different magnetic moment     magnetic separation     ionic liquid    

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探测高超声速滑翔飞行器的区间二型模糊逻辑雷达任务优先级分配方法 Research Articles

孟繁卿1,田康生2

《信息与电子工程前沿（英文）》 2022年 第23卷 第3期   页码 488-501 doi: 10.1631/FITEE.2000560

摘要： 针对相控阵雷达探测临近空间高超声速滑翔飞行器时的资源管理问题，设计了一种基于区间二型模糊逻辑系统的雷达任务优先级分配方法。详细阐述了雷达任务数学模型、高超声速滑翔目标的运动模型和探测模型。将高超声速滑翔飞行器的目标威胁划分为机动威胁、速度威胁、方位威胁和距离威胁。此方法中，机动因子、速度、方位、距离和初始优先级为输入变量，雷达任务优先级为输出变量。为减少模糊规则数、避免规则爆炸，设计了分层结构的区间二型模糊逻辑系统。最后，通过仿真验证该方法可行性。结果表明，基于区间二型模糊逻辑系统的任务优先级分配方法具有更高的精确跟踪率、平均初始优先级和目标威胁度以及更短的偏移时间。

关键词： 高超声速滑翔飞行器；相控阵雷达；区间二型模糊逻辑系统；优先级分配    

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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

Dynamic modulation performance of ferroelectric liquid crystal polarization rotators and Mueller matrix

Song ZHANG, Lelun WANG, Anze YI, Honggang GU, Xiuguo CHEN, Hao JIANG, Shiyuan LIU

期刊论文

一种用于多功能相控阵雷达调度的混合遗传粒子群算法

Hao-wei ZHANG, Jun-wei XIE, Wen-long LU, Chuan SHENG, Bin-feng ZONG

期刊论文

Effect of polymer structures on electro-optical properties of polymer stabilized liquid crystal films

WANG Shoulian, HE Jie, ZENG Yu, YAN Bin, WANG Yinghan

期刊论文

Room temperature liquid metal: its melting point, dominating mechanism and applications

Junheng FU, Chenglin ZHANG, Tianying LIU, Jing LIU

期刊论文

基于光谱辐射信息的高温目标图像识别

范学良,程晓舫,许军

期刊论文

LCF behavior and life prediction method of a single crystal nickel-based superalloy at high temperature

Zhihua ZHANG,Huichen YU,Chengli DONG

期刊论文

Perspective on gallium-based room temperature liquid metal batteries

期刊论文

Assessment of a fuzzy logic based MRAS observer used in a photovoltaic array supplied AC drive

Bhavnesh KUMAR, Yogesh K CHAUHAN, Vivek SHRIVASTAVA

期刊论文

Systematic screening procedure and innovative energy-saving design for ionic liquid-based extractive

期刊论文

Liquid-based high-temperature receiver technologies for next-generation concentrating solar power: A

期刊论文

Harvesting biomechanical energy in the walking by shoe based on liquid metal magnetohydrodynamics

Dan DAI, Jing LIU, Yixin ZHOU

期刊论文

Optimal Su-Do-Ku based interconnection scheme for increased power output from PV array under partial

P. SRINIVASA RAO,P. DINESH,G. SARAVANA ILANGO,C. NAGAMANI

期刊论文

Rare-earth separation based on the differences of ionic magnetic moment via quasi-liquid strategy

期刊论文

探测高超声速滑翔飞行器的区间二型模糊逻辑雷达任务优先级分配方法

孟繁卿1,田康生2

期刊论文