Protocols for calibrating multibeam sonar

Author Posting. © Acoustical Society of America, 2005. This article is posted here by permission of Acoustical Society of America for personal use, not for redistribution. The definitive version was published in Journal of the Acoustical Society of America 117 (2005): 2013-2027, doi:10.1121/1.1869073.Development of protocols for calibrating multibeam sonar by means of the standard-target method is documented. Particular systems used in the development work included three that provide the water-column signals, namely the SIMRAD SM2000/90- and 200-kHz sonars and RESON SeaBat 8101 sonar, with operating frequency of 240 kHz. Two facilities were instrumented specifically for the work: a sea well at the Woods Hole Oceanographic Institution and a large, indoor freshwater tank at the University of New Hampshire. Methods for measuring the transfer characteristics of each sonar, with transducers attached, are described and illustrated with measurement results. The principal results, however, are the protocols themselves. These are elaborated for positioning the target, choosing the receiver gain function, quantifying the system stability, mapping the directionality in the plane of the receiving array and in the plane normal to the central axis, measuring the directionality of individual beams, and measuring the nearfield response. General preparations for calibrating multibeam sonars and a method for measuring the receiver response electronically are outlined. Advantages of multibeam sonar calibration and outstanding problems, such as that of validation of the performance of multibeam sonars as configured for use, are mentioned.Support by the National Science Foundation through Award No. OCE-0002664, NOAA through Grant No. NA97OG0241, and the Cooperative Institute for Climate and Ocean Research (CICOR) through NOAA Contract No. NA17RJ1223 is acknowledged

The Fundamentals : a testimony to the truth (1917) Vol. 3

The biblical conception of sin / Rev. Thomas Whitelaw Paul\u27s testimony to the doctrine of sin / Prof. Charles B. Williams Sin and judgment to come / Sir Robert Anderson What Christ teaches concerning future retribution / Rev. William C. Procter The atonement / Prof. Franklin Johnson At-one-ment, by propitiation / Dyson Hauge The grace of God / C.I. Scofield Salvation by grace / Rev. Thomas Spurgeon The nature of regeneration / Thomas Boston Justification by faith / H.C.G. Moule The doctrines that must be emphasized in successful evangelism / L.W. Munhall Preach the word / Howard Crosby Pastoral and personal evangelism, or winning men to Christ one by one / Rev. John Timothy Stone The Sunday School\u27s true evangelism / Charles Gallaudet Trumbull The place of prayer in evangelism / Rev. R.A. Torrey Foreign missions, or world-wide evangelism / Robert E. Speer A message from mission / Rev. Charles A. Bowen What missionary motives should prevail? / Rev. Henry W. Frost Consecration / Rev. Henry W. Frost Is Romanism Christianity? / T.W. Medhurst Rome, the antagonist of the nation / Rev. J.M. Foster The true church / Bishop Ryle The testimony of foreign missions to the superintending providence of God / Arthur T. Pierson The purposes of the incarnation / Rev. G. Campbell Morgan Tributes to Christ and the Bible by brainy men not known as active Christianshttps://digitalcommons.biola.edu/the-fundamentals/1014/thumbnail.jp