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Joint Estimation of Elevation and Azimuth Angles with Triple-Parallel ULAs Using Metaheuristic and Direct Search Methods
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作者 fawad zaman Adeel Iqbal +1 位作者 Bakhtiar Ali Abdul Khader Jilani Saudagar 《Computer Modeling in Engineering & Sciences》 2025年第11期2535-2550,共16页
Accurate estimation of the Direction-of-Arrival(DoA)of incident plane waves is essential for modern wireless communication,radar,sonar,and localization systems.Precise DoA information enables adaptive beamforming,spat... Accurate estimation of the Direction-of-Arrival(DoA)of incident plane waves is essential for modern wireless communication,radar,sonar,and localization systems.Precise DoA information enables adaptive beamforming,spatial filtering,and interference mitigation by steering antenna array beams toward desired sources while suppressing unwanted signals.Traditional one-dimensional Uniform Linear Arrays(ULAs)are limited to elevation angle estimation due to geometric constraints,typically within the range[0,π].To capture full spatial characteristics in environments with multipath and angular spread,joint estimation of both elevation and azimuth angles becomes necessary.However,existing 2D and 3D array geometries often entail increased hardware complexity and computational cost.This work proposes a novel and efficient framework for joint elevation and azimuth angle estimation using three spatially separated,parallel ULAs.The array configuration exploits spatial diversity and orthogonal projections to capture complete directional information with minimal structural overhead.A customized objective function based on the mean square error between measured and reconstructed array outputs is formulated to guide the estimation process.To solve the resulting non-convex optimization problem,three strategies are investigated:a global Genetic Algorithm(GA),a local Pattern Search(PS),and a hybrid GA-PS method that combines global exploration with local refinement.The proposed framework supports automatic pairing of elevation and azimuth angles,eliminating the need for manual post-processing.Extensive simulations validate the robustness,convergence,and accuracy of all three methods under varying signal-to-noise ratio conditions.Results confirm that the hybrid GA-PS approach achieves superior estimation performance and reduced computational complexity,making it well-suited for real-time and resource-constrained applications in next-generation sensing and communication systems. 展开更多
关键词 Antenna arrays direction of arrival genetic algorithm pattern search
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Identification of the lysine and histidine transporter family in Camellia sinensis and the characterizations in nitrogen utilization 被引量:2
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作者 Wei Huang Danni Ma +9 位作者 fawad zaman Xulei Hao Li Xia E Zhang Pu Wang Mingle Wang Fei Guo Yu Wang Dejiang Ni Hua Zhao 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第1期273-287,共15页
In plants,the lysine and histidine transporter(LHT)family represent a class of proteins that mediate the uptake,translocation,and utilization of amino acids.The tea plant(Camellia sinensis)is a perennial evergreen wit... In plants,the lysine and histidine transporter(LHT)family represent a class of proteins that mediate the uptake,translocation,and utilization of amino acids.The tea plant(Camellia sinensis)is a perennial evergreen with a relatively high level of amino acids.However,systematic identification and molecular characterization of the LHT gene family has rarely been reported in tea plants.In this study,22 CsLHTs were identified from the‘Shuchazao’genome and classified into two groups.The modeled three-dimensional structure and the conserved domains presented a high similarity among the LHTs proteins.Moreover,it was predicted that a few genes were conserved through the analysis of the physiochemical characters,structures and cis-elements in promoters.The expression patterns in tea plants revealed that CsLHT7 was mainly expressed in the roots,and CsLHT4 and CsLHT11 exhibited relatively high expression in both the roots and leaves.Moreover,the expression of all three genes could be induced by organic nitrogen.Additionally,heterogeneous expression of CsLHT4,CsLHT7 and CsLHT11 in Arabidopsis thaliana decreased the aerial parts biomass compared with that in WT plants while significantly increased the rosette biomass only for CsLHT11transgenic plants versus WT plants.Overall,our results provide fundamental information about CsLHTs and potential genes in N utilization for further analysis in tea plants. 展开更多
关键词 Camellia sinensis Nitrogen Lysine and histidine transporter(LHT)family
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Natural variation of main biochemical components,morphological and yield traits among a panel of 87 tea [Camellia sinensis(L.) O. Kuntze] cultivars 被引量:1
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作者 fawad zaman EZhang +9 位作者 Li Xia Xielong Deng Muhammad Ilyas Ahmad Ali Fei Guo Pu Wang Mingle Wang Yu Wang Dejiang Ni Hua Zhao 《Horticultural Plant Journal》 SCIE CAS CSCD 2023年第3期563-576,共14页
Many attentions have been previously focused to identify the multiple biochemical components related to tea quality and health benefits,however, the natural variation of biochemical components present in tea germplasm... Many attentions have been previously focused to identify the multiple biochemical components related to tea quality and health benefits,however, the natural variation of biochemical components present in tea germplasm has not been adequately evaluated. In this study, the main biochemical components, leaf morphological and yield characteristics were evaluated for four rounds of tea leaves in a panel of 87 elite tea cultivars suitable for black, green, or oolong tea. Significant variations were observed among the tea cultivars, as well as seasonal differences in the levels of the free amino acid(FAA), caffeine(CAF), tea polyphenols(TP), water extract(WE) and TP to FAA ratio(TP/FAA). Results showed that the average levels of FAA showed a seasonal change, with the highest level of 4.0% in the 1st spring tea in the cultivars suitable for green tea and the lowest of 3.2% in summer tea in the cultivars suitable for black tea. The average CAF content was highest 3.2% in the cultivars suitable for oolong tea in the 1st spring and the lowest 2.5% in the cultivars suitable for green tea in summer. Limited seasonal and varietal variations were noticed in the average levels of WE among the three categories of tea. In addition, significant natural variation of the morphological characteristics, bud length varying from 2.5 cm to 8.7 cm, bud density from 190.3 buds · m-2to 1 730.3 buds · m-2, mature leaves biomass from 128.4 kg · hm-2to 2 888.4 kg · hm-2, and yield component traits of 100 buds(one bud with two leaves) dry weight from 3.7 g to37.7 g, tea yield/round from 444.6 kg · hm-2to 905.3 kg · hm-2, were observed. The aim of our evaluation was not only to identify the advantages of seasonal and clonal variations but also to provide a new viewpoint for their further application. Representative accessions were selected from the germplasm to promote the establishment of an inherent biochemical constituent expressing the quality of black, green, and oolong tea. The findings might be utilized to establish early selection criteria to enhance the tea breeding and production program. 展开更多
关键词 Camellia sinensis Biochemical components GERMPLASM Natural variation Morphology Yield
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Four-dimensional parameter estimation of plane waves using swarming intelligence
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作者 fawad zaman Ijaz Mansoor Qureshi +1 位作者 Fahad Munir Zafar Ullah Khan 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期754-761,共8页
This paper proposes an efficient approach for four-dimensional (4D) parameter estimation of plane waves impinging on a 2-L shape array. The 4D parameters include amplitude, frequency and the two-dimensional (2D) d... This paper proposes an efficient approach for four-dimensional (4D) parameter estimation of plane waves impinging on a 2-L shape array. The 4D parameters include amplitude, frequency and the two-dimensional (2D) direction of arrival, namely, azimuth and elevation angles. The proposed approach is based on memetic computation, in which the global optimizer, particle swarm optimization is hybridized with a rapid local search technique, pattern search. For this purpose, a new multi-objective fitness function is used. This fitness function is the combination of mean square error and the correlation between the normalized desired and estimated vectors. The proposed hybrid scheme is not only compared with individual performances of particle swarm optimization and pattern search, but also with the performance of the hybrid genetic algorithm and that of the traditional approach. A large number of Monte-Carlo simulations are carried out to validate the performance of the proposed scheme. It gives promising results in terms of estimation accuracy, convergence rate, proximity effect and robustness against noise. 展开更多
关键词 amplitude estimation direction of arrival estimation frequency estimation genetic algorithm
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Flower Pollination Heuristics for Parameter Estimation of Electromagnetic Plane Waves
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作者 Sadiq Akbar Muhammad Asif Zahoor Raja +2 位作者 Naveed Ishtiaq Chaudhary fawad zaman Hani Alquhayz 《Computers, Materials & Continua》 SCIE EI 2021年第8期2529-2543,共15页
For the last few decades,the parameter estimation of electromagnetic plane waves i.e.,far field sources,impinging on antenna array geometries has attracted a lot of researchers due to their use in radar,sonar and unde... For the last few decades,the parameter estimation of electromagnetic plane waves i.e.,far field sources,impinging on antenna array geometries has attracted a lot of researchers due to their use in radar,sonar and under water acoustic environments.In this work,nature inspired heuristics based on the flower pollination algorithm(FPA)is designed for the estimation problem of amplitude and direction of arrival of far field sources impinging on uniform linear array(ULA).Using the approximation in mean squared error sense,a fitness function of the problem is developed and the strength of the FPA is utilized for optimization of the cost function representing scenarios for various number of sources non-coherent located in the far field.The worth of the proposed FPA based nature inspired computing heuristic is established through assessment studies on fitness,histograms,cumulative distribution function and box plots analysis.The other worthy perks of the proposed scheme include simplicity of concept,ease in the implementation,extendibility and wide range of applicability to solve complex optimization problems.These salient features make the proposed approach as an attractive alternative to be exploited for solving different parameter estimation problems arising in nonlinear systems,power signal modelling,image processing and fault diagnosis. 展开更多
关键词 Direction of arrival flower pollination algorithm plane waves parameter estimation
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Detecting faulty sensors in an array using symmetrical structure and cultural algorithm hybridized with differential evolution 被引量:1
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作者 Shafqat Ullah KHAN Ijaz Mansoor QURESHI +1 位作者 fawad zaman Wasim KHAN 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2017年第2期235-245,共11页
The detection of fully and partially defective sensors in a linear array composed of N sensors is addressed. First, the symmetrical structure of a linear array is proposed. Second, a hybrid technique based on the cult... The detection of fully and partially defective sensors in a linear array composed of N sensors is addressed. First, the symmetrical structure of a linear array is proposed. Second, a hybrid technique based on the cultural algorithm with differential evolution is developed. The symmetrical structure has two advantages: (1) Instead of finding all damaged patterns, only (N-1)/2 patterns are needed; (2) We are required to scan the region from 0° to 90°instead of from 0° to 180°. Obviously, the computational complexity can be reduced. Monte Carlo simulations were carried out to validate the performance of the proposed scheme, compared with existing methods in terms of computational time and mean square error. 展开更多
关键词 Cultural algorithm Differential evolution Linear symmetrical sensor array
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