%\cite{Hu:FEL2015-WEP037} \bibitem{Hu:FEL2015-WEP037} J.~Hu, H.-S.~Kang, and H.-S.~Lee, \textquotedblleft{Development Activites Related to RF Cables for Good Phase Stability}\textquotedblright, % in \emph{Proc. FEL2015}, WEP037, pp. 654--657, % in \emph{Proc. FEL2015}, Daejeon, Republic of Korea, August 2015, paper WEP037, pp. 654--657, in \emph{Proc. 37th International Free Electron Laser Conference (FEL2015)}, Daejeon, Republic of Korea, August 2015, paper WEP037, pp. 654--657, ISBN: 978-3-95450-134-2, \url{http://accelconf.web.cern.ch/AccelConf/FEL2015/papers/wep037.pdf}, doi:10.18429/JACoW-FEL2015-WEP037, 2015.