CONTRIBUTORS TO THIS ISSUE 533 



Murray Hill until 1955 with particular emphasis on electron beam 

 studies. He is now at the Allentown, Pa., laboratory where he is en- 

 gaged in the development of microwave oscillators. Member of the 

 Institute of Radio Engineers, Sigma Xi, Eta Kappa Nu, Pi Mu Epsilon. 



Charles S. Thaeler, Moravian College, 1923-25, Lehigh University 

 1925-28, E.E., 1928. During the summer of 1927 he was employed by the 

 Bell Telephone Company of Pennsylvania, returning there after gradua- 

 tion, where he was concerned with transmission engineering and the 

 Toll Fundamental Plan. In 1943 he was on loan to the Operating and 

 Engineering Department of the A.T.&T. Co., working on toll transmis- 

 sion studies. From 1944 to the present he has been with the Operating 

 and Engineering Department and is currently engaged in toll circuit 

 noise and crosstalk problems on open wire and cable systems. Mr. 

 Thaeler is an Associate Member of A.I.E.E., and member of Phi Beta 

 I Kappa, Tau Beta Pi, and Eta Kappa Nu. 



Ping King Tien, B. S., National Central University, China, 1942; 

 M.S., 1948, Ph.D., 1951, Stanford University; Stanford Microwave 

 ]>aboratory, 1949-50; Stanford Electronics Research Laboratory, 1950- 

 52; Bell Telephone Laboratories, 1952-. Since joining the Laboratories, 

 ' Dr. Tien has been concerned with microwave tube research, particularly 

 t raveling- wave tubes. In the course of this research he has engaged in 

 studies of space charge wave amplifiers, helix propagation, electron beam 

 focusing, and noise. He is a member of Sigma Xi. 



Arthur Uhlir, Jr., B.S., M.S. in Ch.E., Illinois Institute of Tech- 



jnology, 1945, 1948; S.M. and Ph.D. in Physics, University of Chicago, 



' 1950, 1952. Dr. Uhlir has been engaged in many phases of transistor 



development since joining the Laboratories in 1951, including electro- 



I chemical techniques and semiconductor device theory. Since 1952 he 



has participated in the Laboratories' Communications Development 



I'laining Program, giving instruction in semiconductors. Member of 



American Physical Society, Sigma Xi, Gamma Alpha, and the Institute 



' of Radio Engineers. 



Roger I. Wilkinson, B.S. in E.E., 1924, Prof. E.E., 1950, Iowa State 

 College; Northwestern Bell Telephone Company, 1920-21; American 

 Telephone and Telegraph Company, 1924-34; Bell Telephone Labora- 

 tories, 1934-. As a member of the Development and Research Depart- 

 iinent of the A.T.&T. Co., Mr. Wilkinson specialized in the applica- 

 tions of the mathematical theory of probability to telephone problems. 



