928 A. Physical Oceanography OLR (1987) 34 (I 1)

A260. Acoustics

87:6103 Comon, Pierre and Yves Robert, 1987. A systolic

array for computing B A -I. IEEE Trans. Acoust. Speech Signal Process., ASSP-35(6):717-723. Stanford Electronics Lab., Stanford Univ., Stan- ford, CA 94305, USA.

87:6104 Fishman, Louis, J.J. McCoy and S.C. Wales, 1987.

Factorization and path integration of the Helm- holtz equation: numerical algorithm~. J. acoust. Soc. Am., 81(5): 1355-1376. Dept. of Civil Engng, Catholic Univ., Washington, DC 20064, USA.

87:6105 Frankenthal, Shimshon, 1987. The reflection of

radiation from randomly irregular surfaces. J. acoust. Soc. Am., 81(5):1377-1383. Dept. of Interdisciplinary Studies, Tel Aviv Univ., Ramat Aviv, Israel.

87:6106 Frankenthal, Shimshon, 1987. Scintillations of par-

tially coherent signals in nonscattering channels. J. acoust. Soc. Am., 81(5):1399-1405. Faculty of Engng, Tel Aviv Univ., Ramat Aviv, Israel.

87:6107 Gostev, V.S. and R.F. Shvachko, 1987. Experimental

study of sound signals observable in the geometric shadow zone of the ocean. Dokl. Earth Sci. Sect. (a translation of Dokl. Akad. Nauk SSSR), 282(1-6):47-49.

In addition to the presence of sound pulses in the geometric shadow zone due to 'leakage' and bottom reflections, experiments reveal the presence of intermediate 'scattered signals.' On the basis of time-dependent analysis of the structure of these signals, it is hypothesized that the scattered signals are generated within the water column 'in the vicinity of a caustic surface formed in the near sound-irradiated zone,' with arrivals from the scat- tered signals having travelled over several different ray paths. Andreyev Inst. of Acoustics, Acad. of Sci., Moscow, USSR. (hbf)

87:6108 Heinrich, Hartmut, 1986. A comparison of conven-

tional ship-installed 3.5 kHz sub bottom profiler (SBP) and the new KAE 'PARASOUND' illus- trated by a mapping of a deep-sea meander. Dt. hydrogr. Z., 39(6):255-262.

Comparison of two different 3.5 kHz techniques applied to resolve the origin of medium scale bottom

structures in the NE Atlantic revealed obvious advantages for the 'PARASOUND.' Improvements in the resolution/penetration ratio by the 'paramet- ric effect,' the narrow beam angle, digitization of data, display of the record, and comfort in handling provide better information about the upper layers of the sea bed. Combined with a bathymetric mapping system such as Sea Beam or Hydrosweep, this instrument allows fast, detailed charting of bottom structures. Profiling with 10 knots ship speed yielded reasonable results even in a gale. Deutsches Hydro- graphisches Inst., Bernhard Nocht Strasse 78, 2000 Hamburg 4, FRG.

87:6109 Koyuncu, Baki, 1986. A study of PZT-4 transducer

surface motion related to their underwater far field beam patterns. Acoust. Lefts, 10(4):51-58. Phys. Dept., Kuwait Univ., Kuwait.

87:6110 Li, Yuxin, Yihua Yang, Zhikuan Li and Zhongkui

Dong, 1987. An experimental study of deep scattering layer in the South China Sea. Acta oceanol, sin., 6(1):64-67. Inst. of Acoustic, Acad. Sinica, Beijing, People's Republic of China.

87:6111 McDonald, B.E. and W.A. Kuperman, 1987. Time

domain formulation for pulse propagation in- cluding nonlinear behavior at a caustic. J. acoust. Soc. Am., 81(5):1406-1417. NORDA, NSTL Station, MS 39529, USA.

87:6112 Messer, Hagit and Yesheskel Bar-ness, 1987.

Closed-loop least mean square time-delay esti- mator. IEEE Trans. Acoust. Speech Signal Process., AASP-35(4):413-424. School of Engng, Tel-Aviv Univ., Israel.

87:6113 Nakamura, Shigehisa, 1986. A note on ocean sound

fields off Noshiro and the 1983 Japan Sea tsunami. Mer, Tokyo, 24(4):186-192. (In Japa- nese, English abstract.)

Vertical profiles of sound speed off Noshiro and around the epicenter of the 1983 earthquake show that a sound channel formed in August and dis- appeared in March 1983. A theoretical model is constructed to determine a mechanism for the precursor to the 1983 tsunami. Shirahama Oceanogr. Observ., Kyoto Univ., Katada-Hatasaki, Wakaya- ma, 649-22, Japan.