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This paper described the theoretical basis and practical calculation for analyzing fading records obtained by close-spaced recievers in the study of the small-scale irregularities in the ionosphere. Two new correlation methods, the cross-point method (C. P. M.) and the ten-point method (T. P. M.), were proposed and compared experimentally with Phillips and Spencer's complete correlation method (P. S. M.) and Yerg's six-point method (S. P. M.). It is concluded that the C. P. M., compared with other methods, is... This paper described the theoretical basis and practical calculation for analyzing fading records obtained by close-spaced recievers in the study of the small-scale irregularities in the ionosphere. Two new correlation methods, the cross-point method (C. P. M.) and the ten-point method (T. P. M.), were proposed and compared experimentally with Phillips and Spencer's complete correlation method (P. S. M.) and Yerg's six-point method (S. P. M.). It is concluded that the C. P. M., compared with other methods, is more exact and provides for more information about the ionospheric irregularities. The C. P. M., as well as the P. S. M., require the determination of the auto-correlation function of one record and the cross-correlation functions between the three records taken in pairs, and it is therefore quite laborious. Then it is shown that there are some advantages in the application of the T. P. M. which provides for informations as much as that of the C. P. M. and as exact as that of the P. S. M., although the calculation is much simpler, as only 8—10 values of correlation coefficient are required. Moreover, it is pointed out that, utilizing the so called "time-lag plots" y_θ, x_θ, the accuracy of the T. P. M. can be further improved. Therefore it is suggested that the T. P. M. should be adopted as a routine, while the C. P. M. or the improved T. P. M. should be adopted for special occasions or special events for which more accurate results are required. for special occasions or special events for which more accurate results are required. In the viewpoint of labour-saving, applications of the structure function and the aftereffect function to the correlation analysis are discussed. In this paper the author also proposed an extrapolation and interpolation method of the value of correlation coefficient for any spacing and/or any time lag. Consequently, some criteria were established for checking the reliability of the calculated values of ionospheric parameters. Especially the occurrence of imaginary value of the random movement and change velocity can be almost always prevented in the course of analysis. 本文詳細地介紹了武汉采用的交点相关法和十点相关法的理論基础和具体計算方法,并与Philtips和spcncer的相关法(PS法)及Yerg的六点相关法进行了比較。正如理論上所預期到的,武汉的实驗表明:交点法提供的参量最多,也最精确可靠,但計算量与PS法的差不多;十点法提供的参量与交点法的一样多,精确性不此PS法的低,然而計算量比PS法的少得多,与六点法的差不多。文中还討論了利用时移图上曲直线,以进一步提高十点法的精确性,以及在相关分析中采用結构函数和后效函数,以进一步簡化計算的可能性。本文还初步討論了各种相关分析法的誤差間題;并提出了相关函数值在时空上的預报方法,以及根据相关函数的預报值与实測值的对此等,判别在記录分析中有无反常現象,和甄別所求出的参量值是否可疑的方法。最后还特別指出了电离层混乱运动变化速度出現虛数值的可能性,并介紹了消除这种虛数值的方法。 In this paper, a Lacuna phenomenon over Wuchang, China is revealed and studied. The obvious difference between this Lacuna phenomenon and the common one is that it occurs on a geomagnetieally quiet day.Some other very rare phenomena occurring in that day are also studied. It may by a coincidence that several rare phenomena come together on the same day. But at least it enlightens us on that the special events are liable to recognization on geomagnetieally quiet days. 本文揭示和研究了武昌上空电离层频高图中的Lacuna现象,这次现象除具有一般Lacuna现象的主要特征外,显著的不同之处是出现在地磁活动较低的日子.同时研究了Lacuna出现当天的一些异常情况.几个罕见现象集中于一天之内,可能有其偶然性,但由此至少提示了这样一点,即在磁静日特殊事件易于探测,容易辨认. The global seismicity of the second quater of this year with a total of 29 earthquakes,including one earthquake of M7.1 and another of M7.2,approaches the level of activity during the first quater.During the second quater of the year,one earthquake occurred in the sea-ridge zone each month.Compared with that of 1984,the global activity of deep earthquakes was lower.There was a special event which consisted of a deep and a shallow earthquake occurring in succession on Luzon Island.In the attached list of... The global seismicity of the second quater of this year with a total of 29 earthquakes,including one earthquake of M7.1 and another of M7.2,approaches the level of activity during the first quater.During the second quater of the year,one earthquake occurred in the sea-ridge zone each month.Compared with that of 1984,the global activity of deep earthquakes was lower.There was a special event which consisted of a deep and a shallow earthquake occurring in succession on Luzon Island.In the attached list of the paper,there are 16 earthquakes added which were recorded less than M6 by PDE while they were rated a little higher by the Chinese network. 今年第二季度的全球地震活动接近于第一季度的水平,频次仍为29次,发生7.1级和7.2级地震各一次。三个月中,每月都有一次海岭带的地震。同1984年相比,全球深震活动开始减少。吕宋岛有一次深、浅震相继发生的特殊震例。本文附表还补充了 PDE 震级不足6级、而中国台网震级较高的16次地震。
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