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利用TSA/Opal技术实现肾活检石蜡切片多重免疫荧光染色
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作者 王宇 《临床与实验病理学杂志》 CAS 北大核心 2024年第4期442-444,共3页
肾活检病理是肾小球疾病诊断的金标准[1],诊断的手段包括光镜、免疫荧光和电镜。三种观察方法对组织处理的要求不同,因此穿刺的肾活检标本需要人为地进行分割。这一操作容易造成某一观察项目没有肾小球的情况,此外也无法在同一肾小球中... 肾活检病理是肾小球疾病诊断的金标准[1],诊断的手段包括光镜、免疫荧光和电镜。三种观察方法对组织处理的要求不同,因此穿刺的肾活检标本需要人为地进行分割。这一操作容易造成某一观察项目没有肾小球的情况,此外也无法在同一肾小球中同时进行光镜、免疫荧光及电镜观察。尽管在体视镜或普通光学显微镜下分割肾组织可以尽量避免没有肾小球的情况,但操作非常依赖穿刺医师的水平,且对于出现硬化或缺血肾小球的组织,即使在显微镜下辨别穿刺组织中的肾小球亦非常困难。更重要的是,对于仅表现为局灶性病变的疾病,人为分割很可能导致在一个检查项目中观察到病变,在另外的检查项目中观察不到。此外,三种观察手段的观察重点不同,免疫荧光主要观察是否存在免疫复合物及补体的沉积,光镜主要观察整体的形态学改变,电镜则主要观察超微结构异常。尽管三种观察方法是分开的,但我们需要整合三种观察内容对疾病进行整体分析,因此假如在同一肾小球中能同时获得免疫、形态学和超微结构的信息更有利于我们做出准确的诊断和开展发病机制的研究。 展开更多
关键词 肾活检 石蜡切片 tsa OPAL 免疫荧光
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非连续性文本阅读学生易错成因及教学对策——基于TSA阅读测试数据的结果分析 被引量:1
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作者 陈丽曼 唐书哲 《中小学课堂教学研究》 2024年第1期60-65,共6页
非连续性文本是英语阅读测试的重点。随着数字时代的到来,文本呈现出明显的多模态化和多元化特征,对学生的阅读素养提出了更高的要求。文章以沿海S市小学五年级学生为研究对象,利用SOLO理论对受试对象在TSA非连续性文本阅读测试中的表... 非连续性文本是英语阅读测试的重点。随着数字时代的到来,文本呈现出明显的多模态化和多元化特征,对学生的阅读素养提出了更高的要求。文章以沿海S市小学五年级学生为研究对象,利用SOLO理论对受试对象在TSA非连续性文本阅读测试中的表现进行分析。结果显示:学生具备语言基础知识,在低层级区间思维表现较好,但“看”的能力和信息换模态表达能力欠缺,且社会语言知识发展滞后,层级区间思维难以跨越。这一发现与SOLO的层次发展匹配。文章对其症因进行分析,并结合当前教学实际提出相应的教学对策,认为应加强对学生语用知识和能力的培养,重视对学生多重文本和电子文本阅读能力的培养。 展开更多
关键词 非连续性文本 tsa测试 易错成因 教学对策
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基于TSA-SVM的老人跌倒识别算法
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作者 董明飞 张梅 《兰州文理学院学报(自然科学版)》 2024年第2期34-38,44,共6页
针对老人跌倒检测易受环境影响以及检测不够精确易出现误判的问题,提出了一种基于人体动作传感器的老人跌倒识别检测算法,采用被囊群算法(TSA)优化支持向量机(SVM)模型进行跌倒识别.针对人体动作传感器采集的数据,首先进行特征提取、降... 针对老人跌倒检测易受环境影响以及检测不够精确易出现误判的问题,提出了一种基于人体动作传感器的老人跌倒识别检测算法,采用被囊群算法(TSA)优化支持向量机(SVM)模型进行跌倒识别.针对人体动作传感器采集的数据,首先进行特征提取、降维等预处理,然后将预处理后的数据输入SVM模型进行训练,同时利用TSA算法寻找SVM最优参数,得到最优的跌倒识别模型,利用该模型即可进行跌倒识别.实验结果表明,本文所提算法的跌倒识别检测正确率可达96%以上,具有一定的优越性. 展开更多
关键词 人体动作传感器 跌倒识别 SVM模型 tsa算法
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A Compact UHF Antenna Based on Hilbert Fractal Elements and a Serpentine Arrangement for Detecting Partial Discharg
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作者 Xiang Lin Jian Fang +4 位作者 Ming Zhang Kuang Yin Yan Tian Yingfei Guo Qianggang Wang 《Energy Engineering》 EI 2024年第5期1127-1141,共15页
Efforts to protect electric power systems from faults have commonly relied on the use of ultra-high frequency(UHF)antennas for detecting partial discharge(PD)as a common precursor to faults.However,the effectiveness o... Efforts to protect electric power systems from faults have commonly relied on the use of ultra-high frequency(UHF)antennas for detecting partial discharge(PD)as a common precursor to faults.However,the effectiveness of existing UHF antennas suffers from a number of challenges such as limited bandwidth,relatively large physical size,and low detection sensitivity.The present study addresses these issues by proposing a compact microstrip patch antenna with fixed dimensions of 100 mm×100 mm×1.6 mm.The results of computations yield an optimized antenna design consisting of 2nd-order Hilbert fractal units positioned within a four-layer serpentine arrangement with a fractal unit connection distance of 3.0 mm.Specifically,the optimized antenna design achieves a detection bandwidth for which the voltage standing wave ratio is less than 2 that is approximately 97.3%of the UHF frequency range(0.3–3 GHz).Finally,a prototype antenna is fabricated using standard printed circuit board technology,and the results of experiments demonstrate that the proposed antenna is capable of detecting PD signals at a distance of 8 m from the discharge source. 展开更多
关键词 Power system fault partial discharge UHF antenna fractal antenna micro-strip antenna
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Assessment of the performance of the TOPGNSS and ANN-MB antennas for ionospheric measurements using low-cost u-blox GNSS receivers
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作者 Daniel Okoh Aderonke Obafaye +5 位作者 Oluwakemi Dare-Idowu Babatunde Rabiu Anton Kashcheyev Claudio Cesaroni John Bosco Habarulema Bruno Nava 《Geodesy and Geodynamics》 EI CSCD 2024年第3期291-301,共11页
Low-cost GNSS receivers have recently been gaining reliability as good candidates for ionospheric studies. In line with these gains are genuine concerns about improving the performance of these receivers. In this work... Low-cost GNSS receivers have recently been gaining reliability as good candidates for ionospheric studies. In line with these gains are genuine concerns about improving the performance of these receivers. In this work, we present a comprehensive investigation of the performances of two antennas(the u-blox ANN-MB and the TOPGNSS TOP-106) used on a low-cost GNSS receiver known as the u-blox ZED-F9P. The two antennas were installed on two identical and co-located u-blox receivers. Data used from both receivers cover the period from January to June 2022. Results from the study indicate that the signal strengths are dominantly greater for the receiver with the TOPGNSS antenna than for the receiver with the ANN-MB antenna, implying that the TOPGNSS antenna is better than the ANN-MB antenna in terms of providing greater signal strengths. Summarily, the TOPGNSS antenna also performed better in minimizing the occurrence of cycle slips on phase TEC measurements. There are no conspicuous differences between the variances(computed as 5-min standard deviations) of phase TEC measurements for the two antennas, except for a period around May-June when the TOPGNSS gave a better performance in terms of minimizing the variances in phase TEC. Remarkably, the ANN-MB antenna gave a better performance than the TOPGNSS antenna in terms of minimizing the variances in pseudorange TEC for some satellite observations. For precise horizontal(North and East) positioning, the receiver with the TOPGNSS antenna gave better results, while the receiver with the ANN-MB antenna gave better vertical(Up) positioning. The errors for the receivers of both antennas are typically within about 5 m(the monthly mean was usually smaller than 1 m) in the horizontal direction and within about 10 m(the monthly mean was usually smaller than 4 m) in the vertical direction. 展开更多
关键词 GNSS Ionosphere LOW-COST antenna TOPGNSS U-blox
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Physical design and recent experimental results of the new ICRF antenna on EAST
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作者 杨桦 张新军 +7 位作者 袁帅 秦成明 张伟 G.URBANCZYK 钱金平 刘鲁南 王高翔 陈青青 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第6期169-176,共8页
Two new ICRF antennas operating in the ion cyclotron radio frequency(ICRF) range have been developed for EAST to overcome the low coupling problem of the original antennas.The original ICRF antennas were limited in th... Two new ICRF antennas operating in the ion cyclotron radio frequency(ICRF) range have been developed for EAST to overcome the low coupling problem of the original antennas.The original ICRF antennas were limited in their power capacity due to insufficient coupling.The new antenna design takes into account both wave coupling and absorption processes through comprehensive wave coupling and absorption codes,with the dominant parallel wave number k∥of 7.5 m-1at dipole phasing.Through the use of these new ICRF antennas,we are able to achieve 3.8 MW output power and 360 s operation,respectively.The initial experimental results demonstrate the reliability of the antenna design method. 展开更多
关键词 ICRF antenna COUPLING EAST
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Prediction of Bandwidth of Metamaterial Antenna Using Pearson Kernel-Based Techniques
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作者 Sherly Alphonse S.Abinaya Sourabh Paul 《Computers, Materials & Continua》 SCIE EI 2024年第3期3449-3467,共19页
The use of metamaterial enhances the performance of a specific class of antennas known as metamaterial antennas.The radiation cost and quality factor of the antenna are influenced by the size of the antenna.Metamateri... The use of metamaterial enhances the performance of a specific class of antennas known as metamaterial antennas.The radiation cost and quality factor of the antenna are influenced by the size of the antenna.Metamaterial antennas allow for the circumvention of the bandwidth restriction for small antennas.Antenna parameters have recently been predicted using machine learning algorithms in existing literature.Machine learning can take the place of the manual process of experimenting to find the ideal simulated antenna parameters.The accuracy of the prediction will be primarily dependent on the model that is used.In this paper,a novel method for forecasting the bandwidth of the metamaterial antenna is proposed,based on using the Pearson Kernel as a standard kernel.Along with these new approaches,this paper suggests a unique hypersphere-based normalization to normalize the values of the dataset attributes and a dimensionality reduction method based on the Pearson kernel to reduce the dimension.A novel algorithm for optimizing the parameters of Convolutional Neural Network(CNN)based on improved Bat Algorithm-based Optimization with Pearson Mutation(BAO-PM)is also presented in this work.The prediction results of the proposed work are better when compared to the existing models in the literature. 展开更多
关键词 antenna pearson optimization BANDWIDTH METAMATERIAL
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基于CEEMD-ITSA-BiLSTM组合模型的短期负荷预测
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作者 高典 张菁 《电子科技》 2024年第4期30-37,共8页
准确预测电力系统短期负荷有助于灵活规划系统资源、合理安排机组工作调度以及提高系统运行效率。针对负荷预测精度问题,文中提出了一种基于CEEMD-ITSA-BiLSTM(Complete Ensemble Empirical Mode Decomposition-Improved Tunicate Swarm... 准确预测电力系统短期负荷有助于灵活规划系统资源、合理安排机组工作调度以及提高系统运行效率。针对负荷预测精度问题,文中提出了一种基于CEEMD-ITSA-BiLSTM(Complete Ensemble Empirical Mode Decomposition-Improved Tunicate Swarm Algorithm-Bidirectional Long Short-Term Memory)的短期负荷预测模型。对时序性负荷数据进行CEEMD分解,得到若干个平稳的IMF(Intrinsic Mode Function),并对每个IMF进行BiLSTM建模预测。为了提高BiLSTM的精度,采用ITSA算法对BiLSTM的隐含层节点数、学习率和训练次数等超参数进行参数寻优,建立CEEMD-ITSA-BiLSTM负荷预测模型。文中以实际负荷数据进行仿真实验,对比了单一BiLSTM和不同算法优化的BiLSTM模型,结果表明CEEMD-ITSA-BiLSTM模型的RMSE(Root Mean Square Error)、MAE(Mean Absolute Error)和MAPE(Mean Absolute Percentage Error)误差指标相比于BiLSTM模型分别提高了48.54%、51.32%和44.78%,显著低于其他对比模型。 展开更多
关键词 短期负荷预测 预测精度 完全集成经验模态分解 本征模函数 被囊群算法 参数寻优 双向长短期记忆神经网络 误差指标
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商品化的预制TSA培养基有效期确定方法的探讨
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作者 寇文月 江雨茹 +6 位作者 郝璐瑶 唐宇毅 周雪云 朱秀娟 钱臻 金歌 王娇娇 《中国药品标准》 CAS 2024年第3期289-295,共7页
目的:通过对商品化的预制胰酪大豆胨琼脂培养基(tryptone soya agar,TSA),在2~25℃避光条件下贮存不同时间质量稳定性的考察,为该类培养基有效期的确定方法进行探讨。方法:选取2个厂家各连续3个批次商品化的预制TSA培养基,分别置2~25℃... 目的:通过对商品化的预制胰酪大豆胨琼脂培养基(tryptone soya agar,TSA),在2~25℃避光条件下贮存不同时间质量稳定性的考察,为该类培养基有效期的确定方法进行探讨。方法:选取2个厂家各连续3个批次商品化的预制TSA培养基,分别置2~25℃避光条件下贮存30、90和180 d,对其进行外观性状检测、pH检测、培养基适用性检查、无菌性检查。结果:2个厂家TSA培养基每批、每个贮存时间点,外观性状检测、pH检测、培养基适用性检查、无菌性检查结果均符合《中国药典》2020年版四部对培养基质量控制的要求。结论:2个厂家生产的TSA培养基在2~25℃避光条件下贮存180 d质量均符合要求,说明两个厂家生产的TSA培养基的有效期均可达到180d。 展开更多
关键词 商品化 tsa培养基 外观性状 PH 培养基适用性 无菌性检查
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Microstrip Patch Antenna with an Inverted T-Type Notch in the Partial Ground for Breast Cancer Detections
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作者 Nure Alam Chowdhury Lulu Wang +2 位作者 Md Shazzadul Islam Linxia Gu Mehmet Kaya 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1301-1322,共22页
This study designs a microstrip patch antenna with an inverted T-type notch in the partial ground to detect tumorcells inside the human breast.The size of the current antenna is small enough(18mm×21mm×1.6mm)... This study designs a microstrip patch antenna with an inverted T-type notch in the partial ground to detect tumorcells inside the human breast.The size of the current antenna is small enough(18mm×21mm×1.6mm)todistribute around the breast phantom.The operating frequency has been observed from6–14GHzwith a minimumreturn loss of−61.18 dB and themaximumgain of current proposed antenna is 5.8 dBiwhich is flexiblewith respectto the size of antenna.After the distribution of eight antennas around the breast phantom,the return loss curveswere observed in the presence and absence of tumor cells inside the breast phantom,and these observations showa sharp difference between the presence and absence of tumor cells.The simulated results show that this proposedantenna is suitable for early detection of cancerous cells inside the breast. 展开更多
关键词 antenna microwave wideband cancer breast phantom tumor detection
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Effect of antenna helicity on discharge characteristics of helicon plasma under a divergent magnetic field
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作者 孙萌 徐晓芳 +3 位作者 王陈文 尹贤轶 陈强 张海宝 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第6期50-59,共10页
The characteristics of the blue core phenomenon observed in a divergent magnetic field helicon plasma are investigated using two different helical antennas, namely right-handed and lefthanded helical antennas. The mod... The characteristics of the blue core phenomenon observed in a divergent magnetic field helicon plasma are investigated using two different helical antennas, namely right-handed and lefthanded helical antennas. The mode transition, discharge image, spatial profiles of plasma density and electron temperature are diagnosed using a Langmuir probe, a Nikon D90 camera,an intensified charge-coupled device camera and an optical emission spectrometer, respectively.The results demonstrated that the blue core phenomenon appeared in the upstream region of the discharge tube at a fixed magnetic field under both helical antennas. However, it is more likely to appear in a right-handed helical antenna, in which the plasma density and ionization rate of the helicon plasma are higher. The spatial profiles of the plasma density and electron temperature are also different in both axial and radial directions for these two kinds of helical antenna. The wavelength calculated based on the dispersion relation of the bounded whistler wave is consistent with the order of magnitude of plasma length. It is proved that the helicon plasma is part of the wave mode discharge mechanism. 展开更多
关键词 helicon plasma non-uniform magnetic field helical antenna blue core discharge mechanism
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Array (Smart) Antennas Improve GSM Performance
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作者 Cornelius A. D. Pahalson Nuhu Habila Hyat Markus Gaga 《International Journal of Communications, Network and System Sciences》 2024年第1期1-10,共10页
As wireless data applications over cellular networks become more widespread, the pressure to increase capacity will become even more intense. Capacity in the 800 and 900 MHz bands, where bandwidth is restricted, is al... As wireless data applications over cellular networks become more widespread, the pressure to increase capacity will become even more intense. Capacity in the 800 and 900 MHz bands, where bandwidth is restricted, is already becoming a limiting factor. This paper attempts to address how the application of smart antenna systems has brought about improvements in call quality and increased capacity through reduced Interference in Mobile Communication. The smart antenna may be in a variety of ways to improve the performance of a communications system. Perhaps most importantly is its capability to cancel co-channel interference. It helps in improving the system performance by increasing the channel capacity, spectrum efficiency, extending range coverage, speech quality, enabling tighter reuse of frequencies within a cellular network and economically, feasible increased signal gain, greater, reduced multipath reflection. It has been argued that Smart antennas and the Algorithms to control them are vital to a high-capacity communication system development. 展开更多
关键词 GSM Signal Quality Smart antenna Carrier-to-Interference Ratio Co-Channel Interference
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A Multi-Token Sector Antenna Neighbor Discovery Protocol for Directional Ad Hoc Networks
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作者 Zhang Hang Li Bo +2 位作者 Yan Zhongjiang Yang Mao Li Xinru 《China Communications》 SCIE CSCD 2024年第7期149-168,共20页
In this paper,we propose a Multi-token Sector Antenna Neighbor Discovery(M-SAND)protocol to enhance the efficiency of neighbor discovery in asynchronous directional ad hoc networks.The central concept of our work invo... In this paper,we propose a Multi-token Sector Antenna Neighbor Discovery(M-SAND)protocol to enhance the efficiency of neighbor discovery in asynchronous directional ad hoc networks.The central concept of our work involves maintaining multiple tokens across the network.To prevent mutual interference among multi-token holders,we introduce the time and space non-interference theorems.Furthermore,we propose a master-slave strategy between tokens.When the master token holder(MTH)performs the neighbor discovery,it decides which 1-hop neighbor is the next MTH and which 2-hop neighbors can be the new slave token holders(STHs).Using this approach,the MTH and multiple STHs can simultaneously discover their neighbors without causing interference with each other.Building on this foundation,we provide a comprehensive procedure for the M-SAND protocol.We also conduct theoretical analyses on the maximum number of STHs and the lower bound of multi-token generation probability.Finally,simulation results demonstrate the time efficiency of the M-SAND protocol.When compared to the QSAND protocol,which uses only one token,the total neighbor discovery time is reduced by 28% when 6beams and 112 nodes are employed. 展开更多
关键词 multi-token neighbor discovery SAND protocol sector antenna ad hoc network
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Kinematic-mapping-model-guided analysis and optimization of 2-PSS&1-RR circular-rail parallel mechanism for fully steerable phased array antennas
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作者 Guodong Tan Xiangfei Meng +4 位作者 Xuechao Duan Lulu Cheng Dingchao Niu Shuai He Dan Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第8期136-154,共19页
This paper presents a systematic methodology for analyzing and optimizing an innovative antenna mount designed for phased array antennas, implemented through a novel 2-PSS&1-RR circular-rail parallel mechanism. In... This paper presents a systematic methodology for analyzing and optimizing an innovative antenna mount designed for phased array antennas, implemented through a novel 2-PSS&1-RR circular-rail parallel mechanism. Initially, a comparative motion analysis between the 3D model of the mount and its full-scale prototype is conducted to validate effectiveness. Given the inherent complexity, a kinematic mapping model is established between the mount and the crank-slider linkage, providing a guiding framework for subsequent analysis and optimization. Guided by this model, feasible inverse and forward solutions are derived, enabling precise identification of stiffness singularities. The concept of singularity distance is thus introduced to reflect the structural stiffness of the mount. Subsequently, also guided by the mapping model, a heuristic algorithm incorporating two backtracking procedures is developed to reduce the mount's mass. Additionally, a parametric finite-element model is employed to explore the relation between singularity distance and structural stiffness. The results indicate a significant reduction(about 16%) in the antenna mount's mass through the developed algorithm, while highlighting the singularity distance as an effective stiffness indicator for this type of antenna mount. 展开更多
关键词 Innovative antenna mount Circular rail Kinematic mapping model Crank-slider linkage Stiffness singularity BACKTRACKING
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Sparse antenna array design methodologies:A review
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作者 Pan Wu Yan-Hui Liu +1 位作者 Zhi-Qin Zhao Qing-Huo Liu 《Journal of Electronic Science and Technology》 EI CAS CSCD 2024年第3期1-15,共15页
Designing a sparse array with reduced transmit/receive modules(TRMs)is vital for some applications where the antenna system’s size,weight,allowed operating space,and cost are limited.Sparse arrays exhibit distinct ar... Designing a sparse array with reduced transmit/receive modules(TRMs)is vital for some applications where the antenna system’s size,weight,allowed operating space,and cost are limited.Sparse arrays exhibit distinct architectures,roughly classified into three categories:Thinned arrays,nonuniformly spaced arrays,and clustered arrays.While numerous advanced synthesis methods have been presented for the three types of sparse arrays in recent years,a comprehensive review of the latest development in sparse array synthesis is lacking.This work aims to fill this gap by thoroughly summarizing these techniques.The study includes synthesis examples to facilitate a comparative analysis of different techniques in terms of both accuracy and efficiency.Thus,this review is intended to assist researchers and engineers in related fields,offering a clear understanding of the development and distinctions among sparse array synthesis techniques. 展开更多
关键词 Clustered array Nonuniformly spaced array Sparse antenna array Synthesis method Thinned array
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The electrical design of a membrane antenna for a lunar-based low-frequency radio telescope
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作者 Suonanben Fengquan Wu +15 位作者 Kai He Shijie Sun Wei Zhou Minquan Zhou Cong Zhang Jiaqin Xu Qisen Yan Shenzhe Xu Jiacong Zhu Zhao Wang Ke Zhang Haitao Miao Jixia Li Yougang Wang Tianlu Chen Xuelei Chen 《Astronomical Techniques and Instruments》 CSCD 2024年第4期227-238,共12页
Detecting primordial fluctuations from the cosmic dark ages requires extremely large low-frequency radio telescope arrays deployed on the far side of the Moon.The antenna of such an array must be lightweight,easily st... Detecting primordial fluctuations from the cosmic dark ages requires extremely large low-frequency radio telescope arrays deployed on the far side of the Moon.The antenna of such an array must be lightweight,easily storable and transportable,deployable on a large scale,durable,and capable of good electrical performance.A membrane antenna is an excellent candidate to meet these criteria.We study the design of a low-frequency membrane antenna for a lunar-based low-frequency(<30 MHz)radio telescope constructed from polyimide film widely used in aerospace applications,owing to its excellent dielectric properties and high stability as a substrate material.We first design and optimize an antenna in free space through dipole deformation and coupling principles,then simulate an antenna on the lunar surface with a simple lunar soil model,yielding an efficiency greater than 90%in the range of 12-19 MHz and greater than 10%in the range of 5-35 MHz.The antenna inherits the omni-directional radiation pattern of a simple dipole antenna in the 5-30 MHz frequency band,giving a large field of view and allowing detection of the 21 cm global signal when used alone.A demonstration prototype is constructed,and its measured electrical property is found to be consistent with simulated results using|S11|measurements.This membrane antenna can potentially fulfill the requirements of a lunar low-frequency array,establishing a solid technical foundation for future large-scale arrays for exploring the cosmic dark ages. 展开更多
关键词 Membrane antenna Lunar-based radio array Cosmic dark ages
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A Combined Antenna Array Deployment with High Positioning Accuracy and Low Angular Measurement Error
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作者 Wangjie Chen Weiqiang Zhu +3 位作者 Zhenhong Fan Li Wu Yi He Yixiao Wang 《Journal of Beijing Institute of Technology》 EI CAS 2024年第2期141-154,共14页
In this paper,an antenna array composed of circular array and orthogonal linear array is proposed by using the design of long and short baseline“orthogonal linear array”and the circular array ambiguity resolution de... In this paper,an antenna array composed of circular array and orthogonal linear array is proposed by using the design of long and short baseline“orthogonal linear array”and the circular array ambiguity resolution design of multi-group baseline clustering.The effectiveness of the antenna array in this paper is verified by sufficient simulation and experiment.After the system deviation correction work,it is found that in the L/S/C/X frequency bands,the ambiguity resolution probability is high,and the phase difference system error between each channel is basically the same.The angle measurement error is less than 0.5°,and the positioning error is less than 2.5 km.Notably,as the center frequency increases,calibration consistency improves,and the calibration frequency points become applicable over a wider frequency range.At a center frequency of 11.5 GHz,the calibration frequency point bandwidth extends to 1200 MHz.This combined antenna array deployment holds significant promise for a wide range of applications in contemporary wireless communication systems. 展开更多
关键词 antenna array deployment ambiguity resolution phase consistency angle measurement error positioning error
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Optimization of the Physical Aperture of the Parabolic Reflector Antenna
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作者 Nkordeh Nsikan Akindele Ayoola +2 位作者 Ololade Oladoyin Amadi Eberi Ibinabo Bobmanuel 《Open Journal of Applied Sciences》 2024年第1期182-192,共11页
In fields like astronomy and radar technology, high-gain antennas are required for long-distance communication. Due to its relatively large gain, the use of parabolic antennas has become very popular over time, becaus... In fields like astronomy and radar technology, high-gain antennas are required for long-distance communication. Due to its relatively large gain, the use of parabolic antennas has become very popular over time, because they can easily achieve gains of above 30 dB at microwave and higher frequencies. Today, most systems’ success depends on how well the antennas perform. These antennas are available in different types and sizes. Each antenna’s effective area usually has less than the actual physical area of the antenna surface. This means that the unused area of the antenna is massive, and a waste. The aim of the research is to show that the actual physical aperture of a parabolic antenna can be reduced as much as possible to equal the effective area, as given by the antenna formula, thereby saving manufacturing costs, improve the aesthetics. In other words, the focus of this work is to experimentally show that reflector antenna can be made of smaller sizes but better performance. Measurements were taken from different positions from a parabolic antenna, the signal level measured and compared with signal levels for optimal performance. 展开更多
关键词 PARABOLIC antenna RECEPTION MANUFACTURING COST
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A Systematic Review of Computer Vision Techniques for Quality Control in End-of-Line Visual Inspection of Antenna Parts
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作者 Zia Ullah Lin Qi +2 位作者 E.J.Solteiro Pires Arsénio Reis Ricardo Rodrigues Nunes 《Computers, Materials & Continua》 SCIE EI 2024年第8期2387-2421,共35页
The rapid evolution of wireless communication technologies has underscored the critical role of antennas in ensuring seamless connectivity.Antenna defects,ranging from manufacturing imperfections to environmental wear... The rapid evolution of wireless communication technologies has underscored the critical role of antennas in ensuring seamless connectivity.Antenna defects,ranging from manufacturing imperfections to environmental wear,pose significant challenges to the reliability and performance of communication systems.This review paper navigates the landscape of antenna defect detection,emphasizing the need for a nuanced understanding of various defect types and the associated challenges in visual detection.This review paper serves as a valuable resource for researchers,engineers,and practitioners engaged in the design and maintenance of communication systems.The insights presented here pave the way for enhanced reliability in antenna systems through targeted defect detection measures.In this study,a comprehensive literature analysis on computer vision algorithms that are employed in end-of-line visual inspection of antenna parts is presented.The PRISMA principles will be followed throughout the review,and its goals are to provide a summary of recent research,identify relevant computer vision techniques,and evaluate how effective these techniques are in discovering defects during inspections.It contains articles from scholarly journals as well as papers presented at conferences up until June 2023.This research utilized search phrases that were relevant,and papers were chosen based on whether or not they met certain inclusion and exclusion criteria.In this study,several different computer vision approaches,such as feature extraction and defect classification,are broken down and analyzed.Additionally,their applicability and performance are discussed.The review highlights the significance of utilizing a wide variety of datasets and measurement criteria.The findings of this study add to the existing body of knowledge and point researchers in the direction of promising new areas of investigation,such as real-time inspection systems and multispectral imaging.This review,on its whole,offers a complete study of computer vision approaches for quality control in antenna parts.It does so by providing helpful insights and drawing attention to areas that require additional exploration. 展开更多
关键词 Computer vision end-of-line visual inspection of antenna parts machine learning algorithms image processing techniques deep learning models
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Microstrip Leaky-Wave Antenna for Radar Applications
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作者 Ronelle Rudaï Gochincka Gogom Charmolavy Goslavy Lionel Nkouka Moukengue Brice Rodrigue Malonda-Boungou 《Open Journal of Antennas and Propagation》 2024年第2期19-29,共11页
The work in this article focuses on developing and improving the performance of new leaky-wave antenna configurations that can be adapted for use in radar systems. The study focused on the W-band, where we demonstrate... The work in this article focuses on developing and improving the performance of new leaky-wave antenna configurations that can be adapted for use in radar systems. The study focused on the W-band, where we demonstrated the possibility of modifying resonant frequencies and reducing the number of patches required. The antenna was designed using HFSS, based on the finite element method. It we designed enabled us to observe the influence of the number of patches on the radiation pattern, and also to achieve low levels of minor’s lobes. and good directivity at the operating frequency. These patches are arranged in the shape of an inverted T. The interest of this study is to meet the requirements of radar antennas dedicated to detection. 展开更多
关键词 Leaky-Wave antenna MICROSTRIP HFSS Radar Applications
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