$\begin{figure}\begin{tabular}{lr} & \psfig{figure=0134+329_11cm.ps,width=8.3cm,... ..._1.3cm.ps,width=8.3cm,height=5.2cm,angle=90}\\ & \\ \end{tabular}\end{figure}$

Figure 1: Light curves of sources 0016+731 at $\lambda =6$ and 2.8cm, 0134+329 at $\lambda =11$ , 6, 2.8 and 1.3 cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} \vspace{5.2cm} & \\ \psfig{figure=0153+744_6... ...height=5.2cm,angle=90}\\ & \\ \vspace{5.2cm} & \\ \end{tabular}\end{figure}$

Figure 2: Light curves of sources 0153+744 and 0212+735 at $\lambda =6$ and 2.8cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} \psfig{figure=0235+164_11cm.ps,width=8.3cm,hei... ..._1.3cm.ps,width=8.3cm,height=5.2cm,angle=90}\\ & \\ \end{tabular}\end{figure}$

Figure 3: Light curves of sources 0235+164 and 0316+413 at $\lambda =11$ , 6, 2.8 and 1.3cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} \psfig{figure=0420-014_11cm.ps,width=8.3cm,hei... ..._1.3cm.ps,width=8.3cm,height=5.2cm,angle=90}\\ & \\ \end{tabular}\end{figure}$

Figure 4: Light curves of sources 0420-014 and 0454+844 at $\lambda =11$ , 6, 2.8 and 1.3cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} \psfig{figure=0518+165_11cm.ps,width=8.3cm,hei... ..._1.3cm.ps,width=8.3cm,height=5.2cm,angle=90}\\ & \\ \end{tabular}\end{figure}$

Figure 5: Light curves of sources 0518+165 and 0528+134 at $\lambda =11$ , 6, 2.8 and 1.3 cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} \psfig{figure=0538+498_11cm.ps,width=8.3cm,he... ...cm.ps,width=8.3cm,height=5.2cm,angle=90} & \\ & \\ \end{tabular}\end{figure}$

Figure 6: Light curves of sources 0538+498 at $\lambda =11$ , 6, 2.8 and 1.3cm, 0615+820 at $\lambda =6$ and 2.8 cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} \psfig{figure=0716+714_11cm.ps,width=8.3cm,hei... ...cm.ps,width=8.3cm,height=5.2cm,angle=90} & \\ & \\ \end{tabular}\end{figure}$

Figure 7: Light curves of sources 0716+714 at $\lambda =11$ , 6, 2.8 and 1.3cm, 0735+178 at $\lambda =6$ cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} \psfig{figure=0804+499_11cm.ps,width=8.3cm,hei... ...cm.ps,width=8.3cm,height=5.2cm,angle=90} & \\ & \\ \end{tabular}\end{figure}$

Figure 8: Light curves of source 0804+499 at $\lambda =11$ , 6, 2.8 and 1.3cm, 0835+580 at $\lambda =11$ , 6 and 2.8 from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} \psfig{figure=0836+710_11cm.ps,width=8.3cm,hei... ..._1.3cm.ps,width=8.3cm,height=5.2cm,angle=90}\\ & \\ \end{tabular}\end{figure}$

Figure 9: Light curves of sources 0836+710 and 0851+202 at $\lambda =11$ , 6, 2.8 and 1.3cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} \psfig{figure=0917+624_11cm.ps,width=8.3cm,he... ..._1.3cm.ps,width=8.3cm,height=5.2cm,angle=90}\\ & \\ \end{tabular}\end{figure}$

Figure 10: Light curves of sources 0917+624 and 0923+392 at $\lambda =11$ , 6, 2.8 and 1.3cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} \psfig{figure=0951+699_11cm.ps,width=8.3cm,he... ..._1.3cm.ps,width=8.3cm,height=5.2cm,angle=90}\\ & \\ \end{tabular}\end{figure}$

Figure 11: Light curves of sources 0951+699 at $\lambda =11$ , 6 and 2.8 cm, 0954+658 at $\lambda =11$ , 6, 2.8 and 1.3cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} & \psfig{figure=1150+812_11cm.ps,width=8.3cm,... ...height=5.2cm,angle=90}\\ & \\ \vspace{5.2cm} & \\ \end{tabular}\end{figure}$

Figure 12: Light curves of sources 1039+811 at $\lambda =6$ and 2.8cm, 1150+812 at $\lambda =11$ , 6 and 2.8cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} \psfig{figure=1226+023_11cm.ps,width=8.3cm,hei... ...t=5.2cm,angle=90} & \\ & \\ \vspace{5.2cm} & \\ \end{tabular}\end{figure}$

Figure 13: Light curves of sources 1226+023 at $\lambda =11$ , 6 and 2.8cm, 1253-055 at $\lambda =6$ cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} \psfig{figure=1328+307_11cm.ps,width=8.3cm,hei... ..._1.3cm.ps,width=8.3cm,height=5.2cm,angle=90}\\ & \\ \end{tabular}\end{figure}$

Figure 14: Light curves of sources 1328+307 and 1409+524 at $\lambda =11$ , 6, 2.8 and 1.3 cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} \psfig{figure=1458+718_11cm.ps,width=8.3cm,he... ..._1.3cm.ps,width=8.3cm,height=5.2cm,angle=90}\\ & \\ \end{tabular}\end{figure}$

Figure 15: Light curves of sources 1458+718 at $\lambda =11$ , 6 and 2.8 cm, 1641+399 at $\lambda =11$ , 6, 2.8 and 1.3 cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} \par\psfig{figure=1652+398_11cm.ps,width=8.3c... ..._1.3cm.ps,width=8.3cm,height=5.2cm,angle=90}\\ & \\ \end{tabular}\end{figure}$

Figure 16: Light curves of sources 1652+398 and 1739+522 at $\lambda =11$ , 6, 2.8 and 1.3 cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} \psfig{figure=1749+701_11cm.ps,width=8.3cm,hei... ..._1.3cm.ps,width=8.3cm,height=5.2cm,angle=90}\\ & \\ \end{tabular}\end{figure}$

Figure 17: Light curves of sources 1749+701 at $\lambda =11$ , 6 and 2.8 cm, 1803+784 at $\lambda =11$ , 6, 2.8 and 1.3cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} & \psfig{figure=1928+738_11cm.ps,width=8.3cm,... ..._1.3cm.ps,width=8.3cm,height=5.2cm,angle=90}\\ & \\ \end{tabular}\end{figure}$

Figure 18: Light curves of sources 1823+568 at $\lambda =6$ and 2.8 cm, 1928+738 at $\lambda =11$ , 6, 2.8 and 1.3 cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} \psfig{figure=2007+777_11cm.ps,width=8.3cm,hei... ..._1.3cm.ps,width=8.3cm,height=5.2cm,angle=90}\\ & \\ \end{tabular}\end{figure}$

Figure 19: Light curves of sources 2007+777 and 2105+420 at $\lambda =11$ , 6, 2.8 and 1.3cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} \psfig{figure=2200+420_11cm.ps,width=8.3cm,hei... ..._1.3cm.ps,width=8.3cm,height=5.2cm,angle=90}\\ & \\ \end{tabular}\end{figure}$

Figure 20: Light curves of sources 2200+420 and 2251+158 at $\lambda =11$ , 6, 2.8 and 1.3cm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Years

$\begin{figure}\begin{tabular}{lr} \psfig{figure=0016+731_sp.ps,width=8.3cm,heigh... ...e=0454+844_sp.ps,width=8.3cm,height=5.2cm,angle=90}\\ \end{tabular}\end{figure}$

Figure 21: Radio spectra of sources 0016+731, 0134+329, 0153+744, 0212+735, 0235+164, 0316+413, 0420-014 and 0454+844 at $\lambda$ ranging from 21 cm to 7 mm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Frequency in GHz

$\begin{figure}\begin{tabular}{lr} \psfig{figure=0518+165_sp.ps,width=8.3cm,heig... ...e=0835+580_sp.ps,width=8.3cm,height=5.2cm,angle=90}\\ \end{tabular}\end{figure}$

Figure 22: Radio spectra of sources 0518+165, 0528+134, 0538+498, 0615+820, 0716+714, 0735+178, 0804+499 and 0835+580 at $\lambda$ ranging from 21 cm to 7 mm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Frequency in GHz

$\begin{figure}\begin{tabular}{lr} \psfig{figure=0836+710_sp.ps,width=8.3cm,heigh... ...e=1150+812_sp.ps,width=8.3cm,height=5.2cm,angle=90}\\ \end{tabular}\end{figure}$

Figure 23: Radio spectra of sources 0836+710, 0851+202, 0917+624, 0923+392, 0951+699, 0954+658, 1039+811 and 1150+812 at $\lambda$ ranging from 21 cm to 7 mm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Frequency in GHz.

$\begin{figure}\begin{tabular}{lr} \psfig{figure=1226+023_sp.ps,width=8.3cm,heig... ...e=1739+522_sp.ps,width=8.3cm,height=5.2cm,angle=90}\\ \end{tabular}\end{figure}$

Figure 24: Radio spectra of sources 1226+023, 1253-055, 1328+307, 1409+524, 1458+718, 1641+399, 1652+398 and 1739+522 at $\lambda$ ranging from 21 cm to 7 mm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Frequency in GHz

$\begin{figure}\begin{tabular}{lr} \psfig{figure=1749+701_sp.ps,width=8.3cm,heig... ...e=2251+158_sp.ps,width=8.3cm,height=5.2cm,angle=90}\\ \end{tabular}\end{figure}$

Figure 25: Radio spectra of sources 1749+701, 1803+784, 1823+568, 1928+738, 2007+777, 2105+420, 2200+420 and 2251+158 at $\lambda$ ranging from 21 cm to 7 mm from 1994.0 to 1999.6 (from top to bottom). Plotted is the flux density in Jy versus Frequency in GHz

$\begin{figure}\begin{tabular}{lr} \psfig{figure=gal_m.ps,width=8.3cm,height=5.2c... ...a_m.ps,width=8.3cm,height=5.2cm,angle=90} & \\ & \\ \end{tabular}\end{figure}$

Figure 28: Variability strength (modulation index) versus galactic latitude ( $b^{\rm II}$ ), redshift (z), spectral index ( $\alpha _{6}^{11}$ , $\alpha _{2.8}^{6}$ ), and superluminal speed ( $\beta _{\rm a}$ , in unit of speed of light c), respectively

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