IEEE Industrial Electronics and Control Instrumentation Group

X IEEE INDUSTRIAL WETCTRONICS AND CONTROL INSTRUMENTATION GROUP The Industrial Electronics and Control Instrumentation Group is an organization, within the framework of the IEEE, of members with principal professional interest in electronics and electrical sciences as applied to control, treatment, and measurement of industrial processes. All members of the IEEE are eligible for membership in the Group and will receive this TRANSACTIONS upon payment of the annual membership fee of $6.00. For information on joining, write to the IEEE, at the address below. ADMINISTRATIVE COMMITTEE J. E. CASEY Chairman P. 0. Box 546 Bryn Mawr, Pa. 19010 R. E. GENTILE Vice Clairman, New Techniologies Babcock & Wilcox Co. 1562 Beeson St. Alliance, Ohio 44601 Term Expires 1971 J. E. CASEY E. T. DAVIS J. F. KEITHLEY P. E. LEGO M. E. SPILLER J. B. CAROLUS Secretary Leeds & Northrup Co. Sumneytown Pike North Wales, Pa. 19454 A. JONES Vice Chairman, Technical Activities GE Co. 40 Federal St. West Lynn, Mass. 01905 Elected Members Term Expires 1972 M. S. HARTLEY A. JONES E. S. MCVEY R. J. ROMAN J. T. TEMIN R. J. ROMAN Treasurer Eastman Kodak Co. 901 Elmgrove Rd. Rochester, N. Y. 14650 J. T. TEMIN Vice Chairman, Membership Activities Park Ohio Industries, Tocco Div. P. 0. Box 1792 Cleveland, Ohio 44105 Term Expires 1973 J. B. CAROLUS R. A. DAMBACH E. MITTLEMANN R. B. SPOONER R. VANZETTI IEEE TRANSACTIONSO ON INDUSTRIAL ELECTRONICS AND CONTROL INSTRUMENTATION Editor ROBERT B. SPOONER IMPAC Instrument Service 201 E. Carson St. Pittsburgh, Pa. 15219 (The Associate Editors are listed on the inside back cover) THE INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS, INC. Officers JAMES H. MULLIGAN, JR., Presidenit ROBERT H. TANNER, Vice President HAROLD CHESTNUT, Vice Presidenit, Techtnical Activities CLARENCE L. COATES, JR., Vice President, Publicatioji Activities JOHN R. WHINNERY, Secretary RAYMOND W. SEARS, Treasurer Headquarters Staff DONALD G. FrNK, General Manager JOHN L. CALLAHAN, Staff Consultant ELWOOD K. GANNETr, Director, Editorial Services WILLIAM J. HILTY, Director, Convention and Publishing Services WILLIAM J. KEYES, Director, Administrative Service JOHN M. KINN, Director, Educational Services LEON PODOLSKY, Staff Consultant CHARLES F. STEWART, JR., Director, Member Services BETTY J. STILLMAN, Admninistrative Assistant to the General Manager RICHARD M. EMBERSON, Director, Technical Services EDWIN D. MACDONALD, Coijferenice Services SAVA I. SHERR, Standards Editorial Department H. JAMES CARTER, Managing Editor, Transactions Senior Editors: ANDREE ABRAMOFF, ANN H. BURGMEYER, CAROLYNE ELENOWITZ, GAIL S. FERENC Associate Editors: NANCY B. BUDDE, HELEN S. GOLDMAN, MARY M. HALL, RUTH MELNICK, NANCY VIGGIANO IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS AND CONTROL INSTRUMENTATION is published quarterly by The Institute of Electrical and Elec- tronics Engineers, Inc., 345 East 47 Street, New York, N. Y. 10017. Responsibility for the contents rests upon the authors and not upon the IEEE, the Group, or its members. This journal is available in either microfiche or printed form. Individual copies may be purchased at $2.50 (first copy only) by IEEE members and $5.00 per copy by nonmembers. Annual subscription price: IEEE members, dues plus Group fee. Price for non- members available on request. Abstracting is permitted with mention of source. All rights, including translation, are reserved by the IEEE. Re- quests for publication permission should be addressed to the IEEE Editorial Department, 345 East 47 Street, New York, N. Y. 10017. Copyright © 1971 by The Institute of Electrical and Electronics Engineers, Inc. Printed in U.S.A. Second-class postage paid at New York, N. Y. and at additional mailing offices.