Light-Time Effects in Two Eclipsing Binaries V343 AQL and CX AQR by Chun-Hwey Kim, Jang Hae Jeong, Yong Sam Lee

“…Possible causes of secular period variations for two systems were discussed. …”
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The BV Photometry of the RR Lyrae Star, BH Ursae Majoris: Light Curves and Period Study by Chun-Hwey Kim, Jang Hae Jeong

“…We also analyzed all of the available unanalyzed minimum timings and found for the first time that the period of BH UMa has varied dramatically in at least three independent sinusoidal ways superposed on a secularly downward parabola over 66 years. The secular period decreasing rate was obtained as 6.d684 × 10-8 y-1, corresponding to -0.58 s/century. …”
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V700 Cygni: A Dynamically Active W UMa-type Binary Star II by Chun-Hwey Kim, Jang Hae Jeong

“…The small secular period increase is interpreted as a combination of both angular momentum loss (due to magnetic braking) and mass-transfer from the less massive component to the more massive component. …”
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WZ Cephei: A Dynamically Active W UMa-Type Binary Star by Jang Hae Jeong, Chun-Hwey Kim

“…It was found that the orbital period of the system has complexly varied in two cyclical components superposed on a secularly downward parabola over about 80y. The downward parabola, corresponding to a secular period decrease of -9.d97 × 10-8 y-1, is most probably produced by the action of both angular momentum loss (AML) due to magnetic braking and mass-transfer from the massive primary component to the secondary. …”
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A Period Study of the Near Contact Binary EG Cep by Chun-Hwey Kim, Jang Hae Jeong, Yong Sam Lee

“…It was found that the orbital period have varied in a cyclical way superposed on an upward parabola. A secular period increase of 3.22 times 10^{-8} d/y was calculated. …”
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On the Period Change of the Contact Binary GW Cephei by Chun-Hwey Kim, Mi Hwa Song, Joh-Na Yoon, Jang Hae Jeong, Taek-Soo Jeoung, Young-Jae Kim, Jung Yeb Kim

“…The upward parabolic O-C diagram corresponding to a secular period increase of about 4.12 × 10^(-8) d/yr was interpreted as mass being transferred from the lesser to more massive component. …”
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