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Noninvasive interception of circulating leukocyte in vivo by optical tweezer array 被引量:1
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作者 Sisi Ge Jinhua Zhou Xunbin Wei 《Journal of Innovative Optical Health Sciences》 2026年第1期56-69,共14页
The ability to noninvasively manipulate and isolate specific cell populations in vivo is critical for advancing real-time diagnostics,precision medicine,and immunological research.Here,we present a novel and broadly a... The ability to noninvasively manipulate and isolate specific cell populations in vivo is critical for advancing real-time diagnostics,precision medicine,and immunological research.Here,we present a novel and broadly applicable optical trapping system based on a custom-designed 2×3 optical tweezer array,which enables the real-time interception and manipulation of circulating leukocytes in live animals.By utilizing intrinsic velocity differences between leukocytes and red blood cells,the system achieves stable trapping of individual leukocytes in vessels 15-20μm in diameter and decelerates multiple cells in vessels greater than 20μm.Notably,it also enables the optical blockage of lymphatic vessels exceeding 50μm,a previously unreported capability.This label-free,noninvasive approach operates without repeated blood draws and is compatible with diverse vessel geometries and flow dynamics.The system offers a generalizable solution for in vivo cell extraction and analysis,paving the way for high-precision single-cell technologies in biomedical research and clinical translation. 展开更多
关键词 Leukocytes optical tweezer array in vivo interception
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Arbitrary azimuthal optical field manipulation by dual-spiral arrays
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作者 MA Li WANG Ying +2 位作者 LI Min ZHANG Ying ZHAO Bo 《中国光学(中英文)》 北大核心 2025年第4期921-930,共10页
Optical field manipulation,an emerging frontier in photonics,demonstrates significant potential in biomedical microscopy,quantum state engineering,and micro-nano fabrication.To address the critical limitations of curr... Optical field manipulation,an emerging frontier in photonics,demonstrates significant potential in biomedical microscopy,quantum state engineering,and micro-nano fabrication.To address the critical limitations of current optical modulation technologies in achieving full-parameter precision control,we proposed a novel approach for dynamic azimuthal optical field modulation based on dual-spiral arrays.By designing spatially interleaved spiral structures with different initial radii while maintaining identical periodic parameters,we achieved continuous optical modulation spanning the full 0-2πrange in azimuthal field distribution.Through rigorous numerical simulations,we systematically established a quantitative correlation between the structural parameters and azimuthal optical field patterns,revealing,for the first time,a quasi-linear relationship between the radius difference and the resultant optical distribution.This theoretical framework advances our fundamental understanding of structured optical field manipulation as well as provides a new paradigm for programmable photonic device design,with distinct technical advantages in super-resolution imaging and optical tweezer systems. 展开更多
关键词 optical manipulation topological charge spiral array
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Extended Nested Array with a Filled Sensor for DOA Estimation of Non-circular Signals
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作者 LI Xiaolong ZHANG Xiaofei SHEN Zihan 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第1期90-100,共11页
Sparse array design has significant implications for improving the accuracy of direction of arrival(DOA)estimation of non-circular(NC)signals.We propose an extended nested array with a filled sensor(ENAFS)based on the... Sparse array design has significant implications for improving the accuracy of direction of arrival(DOA)estimation of non-circular(NC)signals.We propose an extended nested array with a filled sensor(ENAFS)based on the hole-filling strategy.Specifically,we first introduce the improved nested array(INA)and prove its properties.Subsequently,we extend the sum-difference coarray(SDCA)by adding an additional sensor to fill the holes.Thus the larger uniform degrees of freedom(uDOFs)and virtual array aperture(VAA)can be abtained,and the ENAFS is designed.Finally,the simulation results are given to verify the superiority of the proposed ENAFS in terms of DOF,mutual coupling and estimation performance. 展开更多
关键词 non-circular signal extended nested array sparse array direction of arrival(DOA)estimation sum-difference coarray
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Ultrawide field-of-view integrated optical phased arrays employing multiple orbital angular momentum beams
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作者 Zhen Wang Shuxin Liu +4 位作者 Jingchi Li Yong Zhang Xinyuan Fang Qiwen Zhan Yikai Su 《Advanced Photonics Nexus》 2025年第1期42-49,共8页
Optical phased arrays(OPAs)are crucial in beam-steering applications,particularly as transmitters in light detection and ranging and free-space communication systems.In this paper,we demonstrate a on-chip OPA that emi... Optical phased arrays(OPAs)are crucial in beam-steering applications,particularly as transmitters in light detection and ranging and free-space communication systems.In this paper,we demonstrate a on-chip OPA that emits multiple orbital angular momentum(OAM)beams in different directions,each carrying unique topological charges.By superimposing a forked 1×3 Dammann grating on the grating array,six OAM beams with topological charges of ±3,±4,and±5 can be radiated from the OPA region.The OPA chip was fabricated on a silicon-on-insulator platform,and the simultaneous generation of multiple OAM beams was realized experimentally.The directions of these vortices can be steered by adjusting the wavelength of the input light and the bias voltages of the phase shifters,enabling a remarkable field of view(FOV)of 140 deg×40 deg within a 120-nm wavelength range.We pave the way for developing systems with ultrawide FOVs,improving the resolution of remote sensing and broadening the possibilities of free-space communications. 展开更多
关键词 silicon photonics optical phased array orbital angular momentum.
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Equilateral Triangular Array Formation Configuration Initialization Control for Space⁃Based Gravitational Wave Observatory
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作者 PAN Zhengxu BANDO Mai +1 位作者 ZHU Zhanxia HOKAMOTO Shinji 《Transactions of Nanjing University of Aeronautics and Astronautics》 2025年第S1期12-25,共14页
This paper presents an analysis of an equilateral triangular array formation initialization for space-based gravitational wave observatory(GWO)near Lagrange points in the circular-restricted three-body problem.A stabl... This paper presents an analysis of an equilateral triangular array formation initialization for space-based gravitational wave observatory(GWO)near Lagrange points in the circular-restricted three-body problem.A stable configuration is essential for the continuous observation of gravitational waves(GWs).However,the motion near the collinear libration points is highly unstable.This problem is examined by output regulation theory.Using the tracking aspect,the equilateral triangular array formation is established in two periods and the fuel consumption is calculated.Furthermore,the natural evolution of the formation without control input is analyzed,and the effective stability duration is quantified to determine the timing of control interventions.Finally,to observe the GWs in same direction with different frequency bands,scale reconfiguration is employed. 展开更多
关键词 space-based gravitational wave observatory equilateral triangular array formation initialization Lagrange point output regulation theory
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A new 10K liquid SNP genotyping array for wax gourd and its application in heterosis utilization and cultivars identification
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作者 Dan Liu Lingling Xie +4 位作者 Yuting Lei Bingchuan Tian Daolong Liao Fangfang Wu Baobin Mi 《Journal of Integrative Agriculture》 2026年第2期734-743,共10页
High-throughput single nucleotide polymorphism(SNP) arrays have emerged as essential genotyping tools,significantly accelerating breeding programs and advancing basic research.In this study,a high-throughput 10K SNP g... High-throughput single nucleotide polymorphism(SNP) arrays have emerged as essential genotyping tools,significantly accelerating breeding programs and advancing basic research.In this study,a high-throughput 10K SNP genotyping array for wax gourd was developed using genotyping by target sequencing(GBTS),featuring 10,722 SNPs evenly distributed across all 12 chromosomes,including 278 functional loci associated with key economic traits.To demonstrate its utility,genetic distances among 19 elite inbred lines were calculated from SNP data and correlated with heterosis for single fruit weight.The results revealed that greater genetic distance was associated with higher middle parent heterosis(MPH) for single fruit weight.Furthermore,56 commercial wax gourd cultivars collected from eight regions were selected and genotyped.Population structure analysis,phylogenetic analysis,and principal component analysis(PCA) collectively indicated that these cultivars fall into two major groups.Group I,comprising black or dark green skinned wax gourds,exhibited lower genetic diversity than Group II,which includes green or light green skinned varieties,reflecting shorter genetic distances within Group I.Finally,60 polymorphic SNPs were used to construct DNA fingerprints for distinguishing the 56 cultivars.As the first high-throughput genotyping platform for wax gourd,this SNP array provides an effective and powerful tool for genetic analysis. 展开更多
关键词 wax gourd SNP genotyping array HETEROSIS cultivar identification DNA fingerprint
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A Reconfigurable Omnidirectional Triboelectric Whisker Sensor Array for Versatile Human–Machine–Environment Interaction
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作者 Weichen Wang Jiaqi Zhu +9 位作者 Hongfa Zhao Fei Yao Yuzhu Zhang Xiankuan Qian Mingrui Shu Zhigang Wu Minyi Xu Hongya Geng Wenbo Ding Juntian Qu 《Nano-Micro Letters》 2026年第3期121-140,共20页
Developing effective,versatile,and high-precision sensing interfaces remains a crucial challenge in human-machine-environment interaction applications.Despite progress in interaction-oriented sensing skins,limitations... Developing effective,versatile,and high-precision sensing interfaces remains a crucial challenge in human-machine-environment interaction applications.Despite progress in interaction-oriented sensing skins,limitations remain in unit-level reconfiguration,multiaxial force and motion sensing,and robust operation across dynamically changing or irregular surfaces.Herein,we develop a reconfigurable omnidirectional triboelectric whisker sensor array(RO-TWSA)comprising multiple sensing units that integrate a triboelectric whisker structure(TWS)with an untethered hydro-sealing vacuum sucker(UHSVS),enabling reversibly portable deployment and omnidirectional perception across diverse surfaces.Using a simple dual-triangular electrode layout paired with MXene/silicone nanocomposite dielectric layer,the sensor unit achieves precise omnidirectional force and motion sensing with a detection threshold as low as 0.024 N and an angular resolution of 5°,while the UHSVS provides reliable and reversible multi-surface anchoring for the sensor units by involving a newly designed hydrogel combining high mechanical robustness and superior water absorption.Extensive experiments demonstrate the effectiveness of RO-TWSA across various interactive scenarios,including teleoperation,tactile diagnostics,and robotic autonomous exploration.Overall,RO-TWSA presents a versatile and high-resolution tactile interface,offering new avenues for intelligent perception and interaction in complex real-world environments. 展开更多
关键词 Reconfigurable sensor array Interaction interface Tactile perception Omnidirectional sensor Reversible anchoring
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Cytogenetic characterization and molecular marker development of a novel wheat-Thinopyrum ponticum 5E(5D)disomic substitution line with resistance to powdery mildew and stripe rust
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作者 Xiaofang Cheng Yi Xiao +7 位作者 Luhui Wang Xiaoying Yang Pingchuan Deng Jixin Zhao Changyou Wang Chunhuan Chen Tingdong Li Wanquan Ji 《Journal of Integrative Agriculture》 2026年第1期30-41,共12页
Thinopyrum ponticum(2n=10×=70),a wild relative of common wheat(Triticum aestivum L.),is considered an invaluable genetic resource for wheat improvement due to its abundance of genes conferring resistance to bioti... Thinopyrum ponticum(2n=10×=70),a wild relative of common wheat(Triticum aestivum L.),is considered an invaluable genetic resource for wheat improvement due to its abundance of genes conferring resistance to biotic and abiotic stresses.This study focused on the CH97 line,derived from the BC1F7 progeny of a cross between wheat cv.7182 and Th.ponticum.Cytological evidence showed that CH97 has 42 chromosomes,forming 21 bivalents at meiotic metaphase I,with the bivalents subsequently separating and moving to opposite poles during meiotic anaphase I.Through a combination of fluorescence in situ hybridization(FISH),genomic in situ hybridization(GISH),multicolor GISH(mc-GISH),and liquid array analysis,it was determined that CH97 comprises 40 wheat chromosomes and two alien chromosomes from the Ee genome of Th.ponticum,featuring the absence of a pair of 5D chromosomes and variations in 1B,6B,and 7B chromosomes.These findings confirm that CH97 is a stable wheat-Th.ponticum 5E(5D)alien disomic substitution line.Inoculation experiments revealed that CH97 exhibits high resistance to wheat powdery mildew and stripe rust throughout the growth period,in contrast to the highly susceptible common wheat parent 7182.Compared to 7182,CH97 displayed improvements in thousand-kernel weight and kernel length.Additionally,utilizing specific-locus amplified fragment sequencing(SLAF-seq)technology,chromosome 5E-specific molecular markers were developed and validated,achieving a 33.3% success rate,facilitating marker-assisted selection for disease resistance in wheat.Overall,the CH97 substitution line,with its resistance to diseases and improved agronomic traits,represents valuable new germplasm for wheat chromosome engineering and breeding. 展开更多
关键词 Thinopyrum ponticum disomic substitution line powdery mildew stripe rust SLAF-seq liquid array
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3D printed high-temperature ceramic conformal array antenna:Design,analysis,manufacturing,and testing
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作者 Peng Li Ruibo Li +5 位作者 Zijiao Fan Jiujiu Han Guangda Ding Qunbiao Wang Wanye Xu Paolo Rocca 《Defence Technology(防务技术)》 2026年第1期340-353,共14页
In this study,the design,analysis,manufacturing,and testing of a 3D-printed conformal microstrip array antenna for high-temperature environments is presented.3D printing technology is used to fabricate a curved cerami... In this study,the design,analysis,manufacturing,and testing of a 3D-printed conformal microstrip array antenna for high-temperature environments is presented.3D printing technology is used to fabricate a curved ceramic substrate,and laser sintering and microdroplet spraying processes are used to add the conductive metal on the curved substrate.The problems of gain loss,bandwidth reduction,and frequency shift caused by high temperatures are addressed by using a proper antenna design,with parasitic patches,slots,and metal resonant cavities.The antenna prototype is characterized by the curved substrates and the conductive metals for the power dividers,the patch,and the ground plane;its performance is examined up to a temperature of 600℃in a muffle furnace and compared with the results from the numerical analysis.The results show that the antenna can effectively function at 600℃and even higher temperatures. 展开更多
关键词 Ceramic antenna Conformal array High-temperature environment 3D printing High gain and wide band
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Azimuthal cement evaluation with an acoustic phased-arc array transmitter:numerical simulations and field tests 被引量:2
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作者 车小花 乔文孝 +1 位作者 鞠晓东 王瑞甲 《Applied Geophysics》 SCIE CSCD 2016年第1期194-202,222,共10页
We developed a novel cement evaluation logging tool,named the azimuthally acoustic bond tool(AABT),which uses a phased-arc array transmitter with azimuthal detection capability.We combined numerical simulations and ... We developed a novel cement evaluation logging tool,named the azimuthally acoustic bond tool(AABT),which uses a phased-arc array transmitter with azimuthal detection capability.We combined numerical simulations and field tests to verify the AABT tool.The numerical simulation results showed that the radiation direction of the subarray corresponding to the maximum amplitude of the first arrival matches the azimuth of the channeling when it is behind the casing.With larger channeling size in the circumferential direction,the amplitude difference of the casing wave at different azimuths becomes more evident.The test results showed that the AABT can accurately locate the casing collars and evaluate the cement bond quality with azimuthal resolution at the casing-cement interface,and can visualize the size,depth,and azimuth of channeling.In the case of good casingcement bonding,the AABT can further evaluate the cement bond quality at the cementformation interface with azimuthal resolution by using the amplitude map and the velocity of the formation wave. 展开更多
关键词 Cement bond quality phased-arc array transmitter azimuthal resolution AMPLITUDE arrival time
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BLIND PARAFAC SIGNAL DETECTION FOR UNIFORM CIRCULAR ARRAY WITH POLARIZATION SENSITIVE ANTENNAS 被引量:1
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作者 张小飞 黄希珠 徐大专 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第4期291-296,共6页
The received signal of the polarization sensitive array is proved to have trilinear model characteristics. The blind parallel factor(PARAFAC) signal detection algorithm for the polarization sensitive array is propos... The received signal of the polarization sensitive array is proved to have trilinear model characteristics. The blind parallel factor(PARAFAC) signal detection algorithm for the polarization sensitive array is proposed. The trilinear alternating least square (TALS) algorithm is used to abtain the source matrix, and then the matrix is judged. Simulation results show that the bit error rate (BER) of the detection algorithm is close to that of the non-blind decorrelating method and the algorithm works well under the array error condition. BER difference between the non-blind method and this algorithm is less than 2 dB under a high SNR. The algorithm is blind and robust. The channel fading, the direction of arrive(DOA) imformation and the polarization information are needless in the algorithm. 展开更多
关键词 polarization sensitive array parallel factor trilinear model complete polarization uniform circular array
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Microelectrode array for bioelectrical signal stimulation and recording 被引量:1
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作者 潘海仙 吕晓迎 +3 位作者 王志功 方涛 邱雷 黄宗浩 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期361-366,共6页
A microelectrode array(MEA) is presented, which is composed of 60 independent electrodes with 59 working ones and one reference one, and they are divided into 30 pairs. Except for the reference electrode, each pair ... A microelectrode array(MEA) is presented, which is composed of 60 independent electrodes with 59 working ones and one reference one, and they are divided into 30 pairs. Except for the reference electrode, each pair consists of one stimulating electrode and one recording electrode. Supported by the peripheral circuits, four electrode states to study the bioelectrical signal of biological tissue or slice cultured in-vitro on the surface of the electrodes can be realized through each pair of electrodes. The four electrode states are stimulation, recording, stimulation and recording simultaneously, and isolation. The state of each pair of working electrodes can be arbitrarily controlled according to actual needs. The MEAs are fabricated in printed circuit board (PCB) technology. The total area of the PCB-based MEA is 49 mm × 49 mm. The impedance measurement of MEA is carried out in 0.9% sodium chloride solution at room temperature by means of 2-point measurements with an Agilent LCR meter, and the test signal for the impedance measurement is sinusoidal (AC voltage 50 mV, sweeping frequency 20 Hz to 10 kHz). The electrode impedance is between 200 and 3 kΩ while the frequency is between 500 and 1 000 Hz. The electrode impedance magnitude is inversely proportional to the frequency. Experiments of toad sciatic nerve in-vitro stimulation and recording and signal regeneration between isolated toad sciatic nerves are carried out on the PCB-based MEA. The results show that the MEA can be used for bioelectrical signal stimulation, recording, stimulation and recording simultaneously, and isolation of biological tissues or slices in-vitro. 展开更多
关键词 microelectrode array (MEA) stimulation and recording extracellular recording toad sciatic nerve
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The simulation of far-field wavelets using frequency- domain air-gun array near-field wavelets 被引量:2
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作者 宋建国 邓勇 同昕鑫 《Applied Geophysics》 SCIE CSCD 2013年第4期461-468,512,共9页
Air-gun arrays are used in marine-seismic exploration. Far-field wavelets in subsurface media represent the stacking of single air-gun ideal wavelets. We derived single air-gun ideal wavelets using near-field wavelets... Air-gun arrays are used in marine-seismic exploration. Far-field wavelets in subsurface media represent the stacking of single air-gun ideal wavelets. We derived single air-gun ideal wavelets using near-field wavelets recorded from near-field geophones and then synthesized them into far-field wavelets. This is critical for processing wavelets in marine- seismic exploration. For this purpose, several algorithms are currently used to decompose and synthesize wavelets in the time domain. If the traveltime of single air-gun wavelets is not an integral multiple of the sampling interval, the complex and error-prone resampling of the seismic signals using the time-domain method is necessary. Based on the relation between the frequency-domain phase and the time-domain time delay, we propose a method that first transforms the real near-field wavelet to the frequency domain via Fourier transforms; then, it decomposes it and composes the wavelet spectrum in the frequency domain, and then back transforms it to the time domain. Thus, the resampling problem is avoided and single air-gun wavelets and far-field wavelets can be reliably derived. The effect of ghost reflections is also considered, while decomposing the wavelet and removing the ghost reflections. Modeling and real data processing were used to demonstrate the feasibility of the proposed method. 展开更多
关键词 Air-gun array frequency domain near-field wavelet ghost removal far-field wavelet
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Neuronal signal detecting and stimulating circuit array for monolithic integrated MEA
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作者 谢书珊 王志功 +1 位作者 潘海仙 吕晓迎 《Journal of Southeast University(English Edition)》 EI CAS 2009年第2期175-179,共5页
A neuronal signal detecting circuit and a neuronal signal stimulating circuit designed for a monolithic integrated MEA(micro-electrode array) system are described. As a basic cell of the circuits, an OPA( operation... A neuronal signal detecting circuit and a neuronal signal stimulating circuit designed for a monolithic integrated MEA(micro-electrode array) system are described. As a basic cell of the circuits, an OPA( operational amplifier) is designed with low power, low noise, small size and high gain. The detecting circuit has a chip area of 290 μm × 400 μm, a power dissipation of 2.02 mW, an equivalent input noise of 17.72 nV/ Hz, a gain of 60. 5 dB, and an output voltage from - 2. 48 to + 2. 5 V. The stimulating circuit has a chip area of 130 μm × 290 μm, a power dissipation of 740 μW, and an output voltage from - 2. 5 to 2. 04 V. The parameters show that two circuits are suitable for a monolithic integrated MEA system. The detecting circuit and MEA have been fabricated. The test results show that the detecting circuit works well. 展开更多
关键词 neuronal signal detecting noise micro-electrode array MEA complementary metal-oxide-semiconductor transistor (CMOS) technology
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Optimum Design of Impedance Simulator for Phased Array Antnnas
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作者 吕昕 李世智 《Journal of Beijing Institute of Technology》 EI CAS 1994年第1期63+59-63,共6页
The impedance of a solid state active phased array antenna varing with frequency and beam scanning scanning angle be matched with the solid state active matching network (SSAMN). In order to adjust and measure the rad... The impedance of a solid state active phased array antenna varing with frequency and beam scanning scanning angle be matched with the solid state active matching network (SSAMN). In order to adjust and measure the radar conveniently and Securely, it is necessary for the impedance of the simulator of the phased array antennas to be optimized.Having selected the PIN dilde controlling circuits and the circuit parameters optimized,the simulator circuit is determined through numerical computation The experiment is given in support of the simulation. 展开更多
关键词 phase array antennas impedance inatching simulation optimum design active circuits
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Computer Simulation of Compensation Method for Infrared Focal Plane Array
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作者 康长赓 《Journal of Beijing Institute of Technology》 EI CAS 2000年第3期330-334,共5页
A major motivation for this work is to investigate a method of computer simulation for compensating fixed pattern noise of the infrared focal plane arrays. A mathematical model of the output signal of focal plane arra... A major motivation for this work is to investigate a method of computer simulation for compensating fixed pattern noise of the infrared focal plane arrays. A mathematical model of the output signal of focal plane array was established; a compensating algorithm utilizing reference source was derived and simulating programs were designed. The images of compensating process verify the influence of nonuniformity of responsibility and offset on fixed pattern noise. The result show that simulating method of investigating compensation technology for focal plane arrays is feasible, the generated images and methods can be used to the study of image recognition. 展开更多
关键词 computer simulation mathematical model infrared focal plane array fixed pattern noise NONUNIFORMITY COMPENSATION
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Numerical simulation of an acoustic field generated by a phased arc array in a fluid-filled cased borehole 被引量:9
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作者 Che Xiaohua Qiao Wenxiao +1 位作者 Wang Ruijia Zhao Yuhong 《Petroleum Science》 SCIE CAS CSCD 2014年第3期385-390,共6页
Transducers that are widely applied in cement bond evaluation tools, such as cement bond logs and variable density logs, cannot radiate acoustic energy directionally because of the characteristics of monopole sources.... Transducers that are widely applied in cement bond evaluation tools, such as cement bond logs and variable density logs, cannot radiate acoustic energy directionally because of the characteristics of monopole sources. A phased arc array transmitter, which is a novel transducer that differs from monopole and dipole transducers, is presented in this study. To simulate the acoustic field generated by a phased arc array in a fluid-filled cased borehole with different channelings, a 3D finite-difference time-domain method is adopted. The acoustic field generated by a traditional monopole source is also simulated and compared with the field generated by the phased arc array transmitter. Numerical simulation results show that the phased arc array radiates energy directionally in a narrow angular range in the borehole, thereby compressing the acoustic energy into a narrow range in the casing pipe, the cement, and the formation. We present the analyses of first-arrival waveforms and the amplitudes of casing waves at different azimuthal angles for the two different sources. The results indicate that employing a directional source facilitates azimuthal identification and analysis of possible channeling behind the casing pipe. 展开更多
关键词 Phased arc array azimuthal angle first-arrival amplitude acoustic field cased borehole
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Energy harvester array using piezoelectric circular diaphragm for rail vibration 被引量:4
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作者 Wei Wang Rong-Jin Huang +1 位作者 Chuan-Jun Huang Lai-Feng Li 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第6期884-888,共5页
Generating electric energy from mechanical vibration using a piezoelectric circular membrane array is presented in this paper.The electrical characteristics of the functional array consisted of three plates with varie... Generating electric energy from mechanical vibration using a piezoelectric circular membrane array is presented in this paper.The electrical characteristics of the functional array consisted of three plates with varies tip masses are examined under dynamic conditions.With an optimal load resistor of 11 k,an output power of 21.4 m W was generated from the array in parallel connection at 150 Hz under a pre-stress of 0.8 N and a vibration acceleration of9.8 m/s2.Moreover,the broadband energy harvesting using this array still can be realized with different tip masses.Three obvious output power peaks can be obtained in a frequency spectra of 110 Hz to 260 Hz.The results show that using a piezoelectric circular diaphragm array can increase significantly the output of energy compared with the use of a single plate.And by optimizing combination of tip masses with piezoelectric elements in array,the frequency range can be tuned to meet the broadband vibration.This array may possibly be exploited to design the energy harvesting for practical applications such as future high speed rail. 展开更多
关键词 Energy harvesting array Piezoelectric material Rail vibration
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Simulation and prototype testing of multi-wire drift chamber arrays for the CEE 被引量:8
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作者 Li-Ming Lyu Han Yi +2 位作者 Li-Min Duan Zhao Zhang Zhi-Gang Xiao 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第1期102-111,共10页
The building of a large-scale external-target experiment, abbreviated as CEE, in the cooling storage ring at the Heavy Ion Research Facility in Lanzhou has been planned. The CEE is a multi-purpose spectrometer that wi... The building of a large-scale external-target experiment, abbreviated as CEE, in the cooling storage ring at the Heavy Ion Research Facility in Lanzhou has been planned. The CEE is a multi-purpose spectrometer that will be used for various studies on heavy-ion collisions. A multi-wire drift chamber(MWDC) array is the forward tracking detector of the CEE. In this work, GEANT4 simulations were performed for the MWDC forward tracking array with a focus on the track reconstruction algorithm. Combined with the time of flight information,particle identification is achieved. The residue is about 30 μm, while the tracking efficiency is higher than 90%with the current redundancy. In addition, a prototype of the forward tracking system using three MWDCs was assembled and tested using a high-energy proton beam. The firing efficiency of the detector and the reconstruction accuracy of the prototype were derived. The track residue for the protons at about 400 MeV/c is better than 300 μm, meeting the requirements of the CEE. Suggestions for improving the performance of the forward tracking system are given. 展开更多
关键词 CEE Multi-wire drift chamber array Track finding and reconstruction
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