Parameters Of Various Components Research Articles

Dynamic Response and Optimal Design of Radio Telescope Structure under Wind Load Excitation

The dynamic response of a radio telescope structure under wind load excitation significantly impacts the accuracy of signal reception. To address this issue, this study established a parametric finite element model of a radio telescope to simulate its dynamic response under wind load excitation. An improved Latin hypercube sampling method was applied in the design of experiments (DOEs) to optimize the structural dimensional parameters of various components of the radio telescope with the aim of reducing the dynamic response to wind load. A response surface model and multi-objective genetic algorithm (MOGA) were employed for multi-objective structural optimization of the radio telescope structure. The findings reveal that the thickness of the stiffening ribs, the length of the side of the square hollow pole, the thickness of the middle pole, and the inner diameter of the thin pole are the most influential structural parameters affecting the first-order frequency (F1), second-order frequency (F2), maximum deformation in the x-direction (DX), and maximum deformation in the z-direction (DZ) of the radio telescope, respectively. Optimizing the radio telescope results in a 40.00% improvement in F1 and a 24.16% enhancement in F2, while reducing DX by 43.94% and DZ by 64.25%. The study outcomes offer a comprehensive scheme for optimizing the structural dimensional parameters of various radio telescope components in regions characterized by multiple wind fields.

Key Component Capture and Safety Intelligent Analysis of Beam String Structure Based on Digital Twins

In the construction process of beam string structures, the environmental effect and corresponding mechanical properties of the structure are complex. The problem of the misjudgment of structural safety performance caused by the uncertainty of a structural mechanical parameter analysis under various factors needs to be solved. In this study, a method for capturing key components and an intelligent safety analysis of beam string structures based on digital twins (DTs) was proposed. Combined with the characteristics of DTs mapping feedback, a component capture and security analysis framework was formed. Driven by twin framework, multi-source data for structural safety analysis were obtained and the parameter association mechanism established. Considering the space-time evolution and the interaction between the virtual and real elements of the construction process, a multidimensional model was established. Driven by the Dempster–Shafer (D–S) evidence theory, the fusion of structural mechanics parameters was carried out. The safety of the structure was analyzed intelligently by capturing key structural components, thereby providing a basis for the safety maintenance of the structure. The integration of DTs modeling and multi-source data improves the accuracy and intelligence of structural construction safety analysis. In the analysis process, capturing the key components of the structure is the core step. Taking the construction process of a string supported beam roof (symmetrical structure) in a convention and exhibition center as an example, the outlined research method was applied. Based on DTs and D–S evidence theory, the variation degree of mechanical parameters of various components under temperature was determined. By comprehensively investigating the changes of various mechanical parameters, the key components of the structure were captured. Thus, the intelligent analysis of structural safety was realized. The comparison of data verified that the intelligent method can effectively analyze the safety performance of the structure.

The Application of EDA Technology in the Teaching of Communication Circuits

With the design and simulation of single and double‐tuned amplifiers as an example, this paper discusses the application of NI Multisim, the advanced software, in the communication circuit teaching. Using the NI Multisim simulation platform, the parameters of various components in the circuit can be set freely. The relationship between the specific circuit parameters and the circuit performance can be investigated directly and in depth by referring to the simulation results. The proper combination of NI Multisim simulation software and the NI ELVIS platform can provide an effective training platform for improving the students' comprehensive abilities in circuit design.

Optimization of adaptively modulated optical OFDM modems for multimode fiber-based local area networks [Invited

Focus Issue on Orthogonal-Frequency-Division Multiplexed Communications Systems and Networks The impact of a wide range of different parameters of various components involved in optical modems using adaptively modulated optical orthogonal-frequency-division multiplexing (AMOOFDM) on the transmission performance of AMOOFDM signals is explored thoroughly, in single-channel, unamplified, multimode-fiber (MMF)-based, intensity modulation and direct detection (IMDD) transmission links. Practically available optimum component parameters are identified, based on which the AMOOFDM modems are optimized. It is shown that the optimized AMOOFDM modems enable a >70% increase in the capacity versus reach performance without compromising link loss margins, in comparison with that achieved without modem optimization. In addition, the validity of the identified optimum parameters and the feasibility of the optimized AMOOFDM modems are also statistically verified for implementation in the vast majority of installed MMF links. Statistical investigations show that the optimized AMOOFDM modems can support >50Gbits/s signal transmission over 300m in 99.5% of already installed MMF links with loss margins of >7dB. Furthermore, it is also confirmed statistically that the optimized AMOOFDM modems have excellent performance flexibility and great robustness to various fiber and/or system implementation-related impairments.

Assessment of ground reaction force during scoliotic gait.

Although the causes and progression of adolescent idiopathic scoliosis (AIS) are still unclear, a recent extensive review has indicated a number of possible aetiological factors. Previous investigations, employing gait measurements, have indicated asymmetries in the ground reaction forces and suggest a relationship between these asymmetries, neurological dysfunction and spinal deformity. Using a strain-gauge force platform, the present study has examined the time-domain parameters of various components of the ground reaction force together with impulse. Symmetry indices (SI) between left and right sides have also been estimated. The results show that the patients with a left compensatory curve had a greater SI for a left-side impulse, whilst subjects with little or no compensation had a greater right-side impulse. This indicates that a possible gait compensation is occurring, so that the subjects compensate on the opposite pelvis/lower limb to that of the curve. While indicating the asymmetries between left and right, the results also serve to highlight the value of using kinetic parameters in developing the understanding of the pathogenesis and aetiology of scoliosis.

On the Stark Broadening of Singly Ionized Argon Lines

Using a semi-classical formalism which includes Debye shielding, Stark broadening parameters of various components within the 4 s 2P - 4 p ´ 2P0 multiplet and the 4 p - 4 d (2P 0 - 2P, 2D0 - 2 P, 2D0 - 2D) supermutiplet of Ar II are computed. We show that when various components of a multiplet (supermultiplet or transition array) are broadened inequally by an embedded closelying perturbing level, use of a perturber param eter cut-off at the Debye length can restrain the calculated differences between Stark widths within the multiplet.

Reconstruction of California Current at 5, 8, and 10 Ma Using Radiolarian Indicators: ABSTRACT

Neogene radiolarian assemblage parameters were used on siliceous sediment samples from coastal California to reconstruct the California Current at three time planes (5, 8, and 10 Ma). Primary trends in diversity and abundance parameters of various components of the radiolarian assemblage were found in the east-west, or cross-current, direction. Secondary trends in the direction of current flow (north-south) were also exhibited. The oceanographic history of the boundary-current region was reconstructed from these trends within the radiolarian assemblage. Two significant features reflected by the radiolarian parameters were the California Current width and the degree of oceanographic convergence developed off Baja California. The California Current appears to have been narrower and closer to shore 8 and 10 Ma than 5 Ma, but the convergence off Baja appears to have been better developed 5 and 10 Ma than 8 Ma.