The fractal properties of geomagnetic northward component data (H-component) in the equatorial region during various phases of solar activity over Southeast Asia were investigated and then quantified using the parameter of the Hurst exponent (H). This study began with the identification of existence of spectral peaks and scaling properties in international quiet day H-component data which were measured during three levels of solar activity: low, intermediate, and high. Then, various cases of quiet and disturbed days during different solar activity levels were analyzed using the method that performed the best in the preceding part. In all the years analyzed, multifractal scaling and spectral peaks exist, signifying that the data have fractal properties and that there are external factors driving the fluctuations of geomagnetic activity other than solar activity. The analysis of various cases of quiet and disturbed days generally showed that quiet days had anti-persistence tendencies (H < 0.5) while disturbed days had persistence tendencies (H > 0.5)—generally a higher level of Hurst exponent compared to quiet days. As for long-term quiet day H-component data, it had a Hurst exponent value that was near H ≃ 0.50, while the long-term disturbed day H-component data showed higher values than that of the quiet day.

中文翻译：

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东南亚地区不同太阳活动水平下地磁数据分形特性的识别

研究了东南亚太阳活动不同阶段赤道地区地磁北向分量数据（H分量）的分形特性，然后使用赫斯特指数（H）。这项研究首先确定了在三个太阳活动水平期间测量的国际安静日 H 分量数据中光谱峰和标度特性的存在：低、中和高。然后，使用前面部分中表现最好的方法分析了不同太阳活动水平下的安静和干扰日的各种情况。在所有分析的年份中，存在多重分形标度和光谱峰，表明数据具有分形特性，并且除太阳活动外，还有外部因素驱动地磁活动的波动。对平静和扰乱天的各种案例的分析普遍表明，平静的日子有反持续倾向（H < 0.5），而扰乱的日子有持续倾向（H > 0.5)——与平静的日子相比，通常是更高水平的赫斯特指数。至于长期平静的日子H-组件的数据，它有那附近的Hurst指数值^ h ≃0.50，而长期的不安比安宁的日子一天H-组件的数据显示，较高的值。