Search

People’s traditional music passed down from generation to generation should be heard by the world, and music tunes, as one of the indispensable basic elements of traditional music, need to be studied more deeply and systematically. In this paper, based on modern network information technology, we use big data visualization technology to analyze and study traditional music tunes. Using the RGB color space principle to understand the visualization technology, the number of research literature related to traditional music tunes in the past 20 years is obtained through literature collation, and the chart way of visualization using Sankey diagrams is analyzed to conclude traditional music tunes research. The data show that most research literature on traditional music tunes features an average of 6 articles per year. The number of ephemeral articles has gradually increased over the decade, with the total effective number of articles being about 7 in 2002 and increasing to about 39 in 2022. The research institutions are mainly concentrated in many universities in Henan, Yunnan, Hunan, Guangdong, and Guangxi, but the main traditional music tunes studied in each place also Have differences. The research on traditional music tunes by universities has a guiding and leading role, and the increase and depth of related research literature are also conducive to the protection and inheritance of traditional music tunes and integration and innovation in each region.

In this paper, the Earth's magnetic field models which are widely used in spacecraft attitude control applications are modeled and extensively compared with a reference model. The reference model is obtained utilizing coefficients from the last generation of International Geomagnetic Reference Field (IGRF-12). The validity of this model is verified with the World Magnetic Model (WMM) in terms of intensity and direction of the field. The reference model is then used to evaluate lower-order and approximating models while the influence of effective parameters such as expansion order of modeling, orbit height, inclination, latitude and longitude on accuracy of modeling is investigated. The simulation results for several scenarios are presented and discussed. The linear and nonlinear transformations of the models from orbital frame to spacecraft body frame are compared for a wide range of attitude angles in order to investigate the sensibility and validity of linear transformation. Simulation of a spacecraft attitude control maneuver is performed to demonstrate the importance of the accuracy of the magnetic field model which is implemented in the attitude control system. The results indicated a meaningful increase in control effort when a simplified model was used. This research was aimed to investigate the borders of different geomagnetic field models and transformations for spacecraft attitude control applications. The presented results may lead to a proper choice of the Earth's magnetic field model based on the space mission requirements. [ABSTRACT FROM AUTHOR]