EDITOR IN CHIEFHarry Goldstein, h.goldstein@ieee.org EXECUTIVE EDITORJean Kumagai, j.kumagai@ieee.orgMANAGING EDITORElizabeth A. Bretz, e.bretz@ieee.orgCREATIVE DIRECTORMark Montgomery, m.montgomery@ieee.orgDIRECTOR OF DIGITAL INNOVATIONErico Guizzo, e.guizzo@ieee.orgEDITORIAL DIRECTOR, CONTENT DEVELOPMENTGlenn Zorpette, g.zorpette@ieee.orgFEATURES EDITOREliza Strickland, e.strickland@ieee.orgSENIOR EDITORSEvan Ackerman (Digital), evan.ackerman@ieee.orgLucas Laursen, l.laursen@ieee.orgSamuel K. Moore, s.k.moore@ieee.orgNEWS MANAGERMichael Koziol, m.koziol@ieee.orgSENIOR ASSOCIATE EDITOREmily Waltz, e.waltz@ieee.orgASSOCIATE EDITORSDina Genkina, d.genkina@ieee.orgWillie D. Jones, w.jones@ieee.orgASSISTANT EDITORGwendolyn Rak, g.rak@ieee.org SPECIAL PROJECTSDIRECTORStephen Cass, cass.s@ieee.orgSENIOR ASSOCIATE EDITORMargo Anderson, m.k.anderson@ieee.orgNEW PRODUCT AND AUDIENCE DEVELOPMENT DIRECTORTim Warder, t.warder@ieee.orgAUDIENCE DEVELOPMENT MANAGERLaura Bridgeman, l.bridgeman@ieee.orgCOMMUNITY MANAGERKohava Mendelsohn, k.mendelsohn@ieee.orgDIGITAL PRODUCT DESIGNER Erik Vrielink, e.vrielink@ieee.orgART & PRODUCTION DEPUTY ART DIRECTORBrandon Palacio, b.palacio@ieee.orgPHOTOGRAPHY DIRECTORRandi Klett, randi.klett@ieee.orgASSISTANT PHOTO EDITORNicole Millman, n.millman@ieee.orgPRINT PRODUCTION SPECIALISTSylvana Meneses, s.meneses@ieee.orgDIGITAL PRODUCTION MANAGERMichael Spector, m.spector@ieee.orgSENIOR COPY EDITORJoseph N. Levine, j.levine@ieee.orgCOPY EDITORMichele Kogon, m.kogon@ieee.orgRESEARCH COPY EDITORCheryl Della Pietra, c.dellapietra@ieee.orgADMINISTRATORJose Zambrano, jose.zambrano@ieee.orgCONTRIBUTING EDITORSRina Diane Caballar, Robert N. Charette, Charles Q. Choi, Tom Clynes, Peter Fairley, Edd Gent, W. Wayt Gibbs, Mark Harris, Allison Marsh, Julianne Pepitone, Matthew Smith, Lawrence UlrichTHE INSTITUTEEDITOR IN CHIEFKathy Pretz, k.pretz@ieee.orgASSOCIATE EDITORJoanna Goodrich, j.goodrich@ieee.orgDIRECTOR, PERIODICALS PRODUCTION SERVICESPeter TuohyADVERTISING PRODUCTION MANAGERFelicia Spagnoli, f.spagnoli@ieee.orgADVERTISING PRODUCTION+1 732 562 6334EDITORIAL ADVISORY BOARD, IEEE SPECTRUMHarry Goldstein, Chair; Karanveer Anand, Ella M. Atkins, Yedukondala N. Dwith Chenna, Sangyeun Cho, Hugh Durrant-Whyte, Matthew Eisler, Alissa Fitzgerald, Benjamin Gross, Carlos Gutierrez, Lawrence O. Hall, Benjamin Kroposki, Somdeb Majumdar, Khaled Mokhtar, Ramune Nagisetty, Paul Nielsen, Amit K. Singh, Christoph Stiller, Mini S. Thomas, Boon-Lock Yeo EDITORIAL ADVISORY BOARD, THE INSTITUTEKathy Pretz, Chair; Qusi Alqarqaz, Stamatis Dragoumanos, Madeleine Glick, Harry Goldstein, Francesca Iacopi, Meenakshi Jindal, Lawrence O. Hall, Shashi Raj Pandey, John Purvis, Chenyang XuMANAGING DIRECTOR, PUBLICATIONSSteven HeffnerEDITORIAL CORRESPONDENCEIEEE Spectrum3 Park Ave., 17th FloorNew York, NY 10016-5997EDITORIAL DEPARTMENTTel: +1 212 419 7555 Fax: +1 212 419 7570ADVERTISING INQUIRIES Joerg Wuellner +49 152 2258 4972, jwuellner@wiley.comChris Darch +1 206 867 4165, cdarch@wiley.comCOPYRIGHTS AND TRADEMARKSIEEE Spectrum is a registered trademark owned by The Institute of Electrical and Electronics Engineers Inc.Responsibility for the substance of articles rests upon the authors, not IEEE, its organizational units, or its members. Articles do not represent official positions of IEEE. Readers may post comments online; comments may be excerpted for publication. IEEE reserves the right to reject any advertising.IEEE BOARD OF DIRECTORS PRESIDENT & CEOKathleen A. Kramer, president@ieee.org+1 732 562 3928 Fax: +1 732 981 9515PRESIDENT-ELECTMary Ellen RandallTREASURERGerardo BarbosaSECRETARYForrest D. WrightPAST PRESIDENTThomas M. CoughlinVICE PRESIDENTSTimothy P. Kurzweg, Educational Activities; Antonio Luque, Member & Geographic Activities; W. Clem Karl, Publication Services & Products; Dalma Novak, Technical Activities; Gary R. Hoffman, President, Standards Association; Timothy T. Lee, President, IEEE-USADIVISION DIRECTORSYong Lian (I); H. Alan Mantooth (II); Stefano Bregni (III); Charles M. Jackson (IV); Christina M. Schober (V); Russell D. Meier (VI); Christopher E. Root (VII); Cecilia Metra (VIII); Aylin Yener (IX); Ravinder S. Dahiya (X)REGION DIRECTORSBala S. Prasanna (1); Felicia Reinhart (2); Eric Grigorian (3); Constance A. Kelly (4); A. Matt Francis (5); Joseph C. Wei (6); Thamir F. “Tom” Murad (7); Michael G. Hinchey (8); Jenifer P. Castillo Rodriguez (9); Takako Hashimoto (10)IEEE STAFF EXECUTIVE DIRECTOR & COOSophia A. 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