TY - SER TI - Journal of The Hydraulics Division. Vol. 107 No. 4 (1981) PY - 0000///[date of publication not identified] CY - New York : American Society of Civil Engineers. N1 - It contains of Papers, Discussion on April 1981 in Vol. 107 No. 4; Self-Formed Straight Channels in Sandy Beds / Syunsuke Ikeda. Variation of Karman Constant in Sediment-Laden Flow / Shang-yi Wang. Performance of Baffled Chute with 90 degree Bend / David T. Higgins. Unstable Turbulent Flow in Open Channels / Jean E. Berlamont and Nicole Vanderstappen. Separated Flow Through Large Sudden Expansions / Prabhulal R. Mehta. Simulating Mass Transport in Unconfined Aquifers / Varuttamadhira Guvanasen and Raymond E. Volker. Mathematical Model of Shallow Water Flow over Porous Media / Ali Osman Akan and Ben Chie Yen. TECHNICAL NOTES : Proc. Paper 16154 - Scales for Circular Jets in Cross-Flow / Nallamuthu Rajaratnam and Thimmaiah Gangadharaiah. Sand-Water Slurry Experiment / M. R. Carstens and Graeme Addie. New Design Equations for Scour Around Bridge Piers / Christopher James Baker. DISCUSSION : Proc. Paper 16151 - Estimation of Direct Runoff from Urban Watersheds / Aolad Hossain, A. Ramachandra Rao, and Jacques W. DeUeur (Feb., 1978. Prior Discussion: Aug., 1980). Errata. Estimating Average Velocity in Gravel-Bed Rivers / Dale I. Bray (Sept., 1979. Prior Discussions: Sept., Oct., 1980). Closure. Hydraulic Geometry of Active Gravel Rivers / Gary Parker (Sept., 1979. Prior Discussions: July, Oct., 1980). Closure. Approximate Flood Routing Methods: A Review / P. Erwin Weinmann and Eric M. Laurenson (Dec., 1979. Prior Discussions: Nov., Dec., 1980). Errata; Log Pearson Type 3 Distribution: A Generalized Evaluation by Donthamsetti Veerabhadra Rao (May, 1980) / M. Riazul Hasan. Heat Loss from Sidearms of Cooling Lakes by Terry W. Sturm and John F. Kennedy (May, 1980) / Subhash C. Jain and Nevzat Yildirim. Characteristics of Low Flows by the Task Committee on Low-Flow Evaluation and Needs of the Committee on Surface-Water Hydrology of the Hydraulics Division (May, 1980) / Michel North. Composite Roughness of Natural Channels by Asok K. Motayed and Muthusamy Krishamurthy (June, 1980) / James Grant Mac Broom. Boundary Layers in Developing Open Channel Flow by Edward Silberman (July, 1980) / Edward H. Wilson. Scour Velocities in Ephemeral Channels by William C. Hughes (Sept., 1980) / Subhash C. Mehrotra. Submerged Horizontal Jet over Erodible Bed by S. S. Chatterjee and S. N. Ghosh (Nov., 1980) / Subhash C. Mehrotra ER -