online_modified_lane_k1:  Calculation of parameter k1 of the Modified Lane relation    Formula: k1 = Qs / [ 58.7 γ Qw So (R / ds)1/3 ] SI Units (metric):  Qs in M.Tons/day, Qw in m3/s, So in m/m, R in m, and ds in mm. U.S. Customary Units:  Qs in Tons/day, Qw in ft3/s, So in ft/ft, R in ft, and ds in mm. Reference: http://lane.sdsu.edu INPUT DATA: Select:    SI units (metric) U.S. Customary units Sediment discharge Qs :       Warning: Undefined variable $sedimentdischargeunits in /var/www/html/ponce/onlinemodifiedlanek1.php on line 155 Water discharge Qw :       Warning: Undefined variable $waterdischargeunits in /var/www/html/ponce/onlinemodifiedlanek1.php on line 164 Bottom slope So :       Warning: Undefined variable $bottomslopeunits in /var/www/html/ponce/onlinemodifiedlanek1.php on line 173 Hydraulic radius R :       Warning: Undefined variable $hydraulicradiusunits in /var/www/html/ponce/onlinemodifiedlanek1.php on line 182 Particle size ds :       Warning: Undefined variable $particlesizeunits in /var/www/html/ponce/onlinemodifiedlanek1.php on line 191 OUTPUT: Parameter k1 :    Warning: Undefined variable $parameterk1 in /var/www/html/ponce/onlinemodifiedlanek1.php on line 202 Deprecated: substr(): Passing null to parameter #1 ($string) of type string is deprecated in /var/www/html/ponce/onlinemodifiedlanek1.php on line 202   Press button to or recalculate   Your request was processed at  10:55:06 pm on April 3rd, 2025   [ 250403  22:55:06 ]. Thank you for running   online_modified_lane_k1   Please call again.   [120918]