Tree roots are vital for tree ecosystems; accurate root detection helps analyze the health of trees and supports effective management resources such as fertilizers, water pesticides. In this paper, a deep learning-based ground-penetrating radar (GPR) inversion method is proposed to simultaneously image spatial distribution permittivity subsurface layered heterogeneous soils in real time. Additionally, GPR simulation data set measured built study, which were used train models validate...

Inhalation from ambient air and cigarette smoke is a common route of human exposure to polycyclic aromatic hydrocarbons (PAHs). Little information available regarding hepatotoxicities inhaled PAHs so for. In this study, we evaluated the toxic effects intratracheally instilled benzo[a]pyrene (B[a]P) on hepatic lipid metabolism C57BL/6 mice at relevant environmental levels by using two different mass-based lipidomics approaches. The results mass spectrometry imaging analysis showed that both...

To enhance the intelligence and digital management level of radio telescopes ensure safe stable operation antennas, this paper proposes a real-time state evaluation method for antenna structure based on twin (DT) technology. Firstly, five-dimensional model DT, system (DTs) framework is designed. Secondly, quadric error metrics (QEM) mesh-simplification algorithm mesh-reconstruction technology are employed to obtain lightweight antenna. Furthermore, random forest (RF) regression surrogate...

The design of the Qitai 110 m Radio Telescope (QTT) with large aperture and very high working frequency (115 GHz) was investigated in Xinjiang, China. results lead to a main reflector surface precision pointing precision. In this paper, properties active adjustment deformed parabolic antenna are analyzed. To assure performance antennas such as gain boresight, which can be obtained by utilizing an electromechanical coupling model, satisfy them simultaneously, research on applied new target...

The NanShan Radio Telescope is a 26-m fully steerable radio telescope, and it adopts 6-UPU Stewart platform with electric motors to adjust align the position of subreflector. In order analyze actual dynamic performance control Telescope, this article models inverse using virtual work approach. model improves accuracy equations considered pitching motion base in practical application telescope. Dynamic simulations are implemented, conditions passive rotation piston actuators considered,...

Integrated structural-electromagnetic (EM) optimization design is of great importance in the area antenna design. The quick and exact calculation patterns for distorted reflectors an important research topic. In this communication, based on previous works, a novel pattern approximation method using piecewise linear fitting presented. exponential error term physical optics (PO) formulation first approximated by series straight lines through least-square algorithm. Then, radiation integral...

Based on the works of Yahya Rahmat-Samii, a multiobjective optimization model is developed to analyze effects surface errors' nonuniformity along radius reflector's radiation characteristic. Through model, Pareto front for trading off peak gain loss (PGL) and first sidelobe level increase (SLLI) obtained. Simulations clearly show that same root mean square (rms) error whole reflector, different distributions result in PGLs SLLIs. Then, weighting function rms errors considered evaluation...

Active panels are generally applied in large aperture and high-frequency reflector antennas, the precise calculation of actuator adjustment value is great importance. First, approximation relationship between panel elastic deformation established. Subsequently, a matrix for whole derived to calculate caused by adjustment. Next, root mean square (rms) error deformed expressed as quadratic form form, can be easily promptly from corresponding extreme value. The solution expected unique optimal...

Abstract Complex genetic architecture is the major cause of heterogeneity in epilepsy, which poses challenges for accurate diagnosis and precise treatment. A large number epilepsy candidate genes have been identified from clinical studies, particularly with widespread use next-generation sequencing. Validating these emerging as a valuable yet challenging task. Drosophila serves an ideal animal model validating associated neurogenetic disorders such due to its rapid reproduction rate,...

Aperture expanding and frequency upgrading of full steerable antennas make the electrical performance difficult to guarantee, that radio telescopes operate in a complex environment, so it has improve by some methods like mechanical or electronic compensation.To control pointing accuracy detecting distance antennas, we must adjust position surface shape shaped reflectors, another word, active adjustment is most effective way.Therefore, this article describes situation status applications...

Large reflector antennas are widely used in radars, satellite communication, radio astronomy, and so on. The rapid developments these fields have created demands for development of better performance higher surface accuracy. However, low accuracy efficiency the common disadvantages traditional panel alignment adjustment. In order to improve large antenna, a new method is presented determinate adjustment values from far field pattern. Based on Physical Optics (PO), effect facet displacement...

We extend the concept of best-fitting paraboloids for large single and dual reflectors with conic-section surfaces to best-fit shaped surface uniform amplitude distribution. The point focus paraboloidal main reflector is replaced by focal lines primary subreflector focus, whereas secondary at feed kept. are shaped, all rays from main-reflector aperture meet an equal-path-length condition. This condition may be represented a set “homology parameters” determined least-squares method. Finally,...

Abstract Active reflectors are often used to compensate the surface distortion caused by environmental factors that degrade electromagnetic performance of large high-frequency reflector antennas. This is crucial for maintaining high gain operation in A compensation method active a dual-reflector antenna proposed. relationship established between deformation and optical path difference primary geometric optics. Subsequently, employing finite element analysis, polynomial fitting approach...

There are deviations between the radio telescope antenna finite element (FE) model, founded on design stage, and actual working structure. The original FE model cannot accurately describe structure deformation characteristics under environmental load, thereby compromising accuracy of active structural compensation. This article proposes an updating method parameter optimization with a surrogate model. updates modulus elasticity parameters different components backup (BUS) to obtain analysis...

With the development of large‐aperture and high‐frequency radio telescopes, a surface adjustment procedure for compensation deformations has become great importance. In this study, an innovative strategy is proposed to achieve automated large telescope with adjustable dual reflectors. strategy, high‐precision long‐distance measurement instrument adopted installed on back sub‐reflector measure distances elevation angles target points main reflector. Here, two purposes are discussed. The first...

Integrated structural-electromagnetic design is one of the current research hotspots in area antenna design. In this letter, a mesh refinement method structure finite elements developed to produce electromagnetic grids by constructing quadratic surface over each element. To begin with, normal vector at grid node constructed through linear combination vectors around that node. Then, with help and coordinates, determined element be approximation curved reflector. Lastly, performed on surfaces....

The efficiency of a reflector antenna highly depends on its surface shape. In order to ensure good convergence, the conventional phase retrieval based shape detection schemes require that several far-field intensities be scanned, focused, or defocused. For large antennas, scanning process is time consuming. This paper proposes new method requires only single intensity. Unlike existing methods, it retrieves both amplitude and phase, fact deformed causes change not in aperture but also...

The temperature field caused by solar radiation can seriously affect the electromagnetic (EM) performances of large‐aperture and high‐frequency radio telescopes, achieving EM performance improvements under is great importance. In this study, combining simulation measurement, a fast estimation method presented. First, database based on transient constructed in advance, utilising telescope's axisymmetric structure, dimension be greatly reduced. Then, small number sensors are installed...

In this paper, a method based on the Zernike distribution and optical aberration is proposed to investigate effects of characteristics surface distortions reflector antenna its electromagnetic performance (EMP). For large-scale errors, an analytical model introduced describe arbitrary distortions, orthogonal polynomials. The error described by series typical EMP are analyzed. numerical results indicate that in feature defocus or spherical have greater impact gain, tilt coma mainly influences...

In order to achieve the function of active adjustment primary reflector for QiTai radio Telescope (QTT), a kind high precision positioning actuator is designed and some performances prototype are tested. The scheme adopts stepping motor, angle sensor, ball screw worm gear. detail design simulation key components made, their accuracy, electromagnetic compatibility environmental adaptation especially studied. Accuracy tests prototypes carried out, result indicates that can meet requirement...

Based on the works of Greve and Rahmat-Samii, electromagnetic (EM) performance reflector antenna with non-uniform surface errors along radius is further addressed. A mathematical model developed to describe weighting function for radius. Then, some discussions peak gain loss (PGL) first sidelobe level increase (SLLI) caused by are presented several significant radiation characteristics pointed out. Last, based proposed model, weighted root mean square (RMS) value produced evaluate EM...

Abstract Dual-reflector antennas are widely used in astronomical observations and satellite communication. Structural deformations of the reflectors for radio telescopes inevitable outside working conditions due to exterior environment loads, which will cause distortion surface primary reflector displacement subreflector, then lead gain degradation misalignment. In this paper, influence correction misalignment a dual-reflector antenna have been studied. From perspective wavefront aberration,...

The Nanshan radio telescope (NSRT) is a fully steerable with diameter of 26 meters, located in Urumqi, Xinjiang, China. NSRT currently operate the frequency range from 1.4 GHz to 22.4 GHz。In order reduce effect gravity-induced structural deformations on antenna efficiency and pointing accuracy, subreflector adjustment system has been used adjust position 6 degree-of-freedom correct defocusing reflectors misalignment. Stewart platform as mechanism perform translation -50/+50 mm (along x, y, z...