Vice president Joan Yonkler of Henry J. Kaufman & Associates, a Washington-based communications firm, has been elected to the board of directors. She has been the firm's media director for the past four years, supervising media planning and placement for each of the agency's local and national clients.

Wallace W. Knief, formerly director of corporate communications for Planning Research Corp., has been named vice president of Herb Kelly/Anita Mitchell Associates Inc. of West Palm Beach, Fla.

Knief served as a reginal corporate public relations manager for Litton Industries from 1971 to 1976. Before that he was manager of public relations and advertising for the electronics division of Avoc Corp. He started his public relations career with Martin Marietta Corp. Knief also worked for 13 years as a reporter, editor and manager of weekly and daily newspapers.

Dr. Kenneth H. Rabin, acting director of university relations at American University, has been appointed to the 1980 Accreditation Board of the Public Relations Society of America. Rabin is on leave from his post as director of the Graduate Public Relations Program in the university's Kogod College of Business Administration. The PRSA board grants accreditation to public relations personnel who are members of the society.

The Maryland Center for Public Broadcasting has named Joyce Braga program circulation manager and Rosemary Eck grants acquisition officer, a new position. Braga will be responsible for the nonbroadcast marketing of public television programs available on Video cassette and quadruplex tapes. Eck will be in charge of acquisition of local and national grants to the center from foundations and governmental agencies.

Sandy Hur Bresnahan has joined the staff of Yader & associates Advertising Inc. as an associate. She previously headed her own agency, Sandy Hur Advertising, in Kensington and Washington Grove, Md.

Liz Savage and Kathleen Wilmes have been named vice presidents of Walczy Brown Design of Bethesda, a division of Earle Palmer Brown.