Now showing items 2601-2620 of 3826

    • Optimal Furrow Design. I: Time of Advance Equation 

      John D. Valiantzas (American Society of Civil Engineers, 2001)
      A particularly simple equation is developed to explicitly calculate the time of advance in surface irrigation. The proposed equation can be used for routine furrow irrigation design. The equation is derived as an extension ...
    • Finite Volume Model for Nonlevel Basin Irrigation 

      Scott F. Bradford; Nikolaos D. Katopodes (American Society of Civil Engineers, 2001)
      A finite volume model for unsteady, two-dimensional, shallow water flow is developed and applied to simulate the advance and infiltration of an irrigation wave in two-dimensional basins of complex topography. The fluxes ...
    • Analysis and Design of Furrow Irrigation Systems 

      Dawit Zerihun; Charles A. Sanchez; Kathryn L. Farrell-Poe (American Society of Civil Engineers, 2001)
      Application efficiency is the primary criterion for furrow irrigation system design and management. In this study, the application efficiency function of a furrow irrigation system is analyzed. The application efficiency ...
    • Storage Volume and Overflow Risk for Infiltration Basin Design 

      James C. Y. Guo; William Hughes (American Society of Civil Engineers, 2001)
      This study presents a risk-based approach for the design of infiltration basins. The design parameters include basin storage volume, drain time, and overflow risk. At a basin site, the storm-water detention storage volume ...
    • Infiltration into Freezing and Thawing Soils under Differing Field Treatments 

      Zheng Xiuqing; G. N. Flerchinger (American Society of Civil Engineers, 2001)
      Infiltration characteristics of seasonally frozen soil influence agricultural management and hydrology in many areas. In northern and northwestern China, winter and spring irrigation is conducted during periods with frozen ...
    • Design of Minimum Seepage Loss Canal Sections 

      Sohan L. Atmapoojya; Ramesh N. Ingle; A. R. Kacimov; Prabhata K. Swamee; Govinda C. Mishra; Bhagu R. Chahar (American Society of Civil Engineers, 2001)
    • Rate and Volume of Stream Depletion due to Pumping 

      Sushil K. Singh (American Society of Civil Engineers, 2001)
    • Evaporation Estimation for Lake Okeechobee in South Florida 

      Wossenu Abtew (American Society of Civil Engineers, 2001)
      Lake Okeechobee, located in subtropical South Florida, is the second largest completely contained freshwater lake in the United States. The average, annual evaporation is 132 cm, reported following five years of meteorology ...
    • Modeling Water Distribution for Irrigation Machine with Small Spray Nozzles 

      Mohammad Omary; Harold Sumner (American Society of Civil Engineers, 2001)
      A model and computer program were developed to calculate water application depth and uniformity coefficient for small spray nozzles mounted on a center-pivot irrigation system. The program requires two basic inputs. First, ...
    • Regional Alfalfa Yield, <b><i>ET</i></b><b><sub><i>c</i></sub></b>, and Water Value in Western States 

      M. E. Grismer (American Society of Civil Engineers, 2001)
      Alfalfa hay yield, yield-consumptive use ratio (
    • Bank Profile of Threshold Channels: A Simplified Approach 

      Subhasish Dey (American Society of Civil Engineers, 2001)
      A simplified model is presented for the computation of shape and dimensions of the cross section of a self-formed straight threshold channel with noncohesive uniform sediments. The model is based on the equilibrium of the ...
    • Modeling Soluble Phosphorus Desorption Kinetics in Tile Drainage 

      Christopher A. Scott; Kirk W. Weiler (American Society of Civil Engineers, 2001)
      This paper describes a simple model for the desorption and transport of soluble reactive phosphorus (SRP) to subsurface drains. The model assumes first-order kinetically rate-limited desorption in a soil surface mixing ...
    • Design of Minimum Seepage-Loss Nonpolygonal Canal Sections 

      Prabhata K. Swamee; Deepak Kashyap (American Society of Civil Engineers, 2001)
      Analytical solutions exist for the problem of determination of seepage loss from polygonal sections such as a triangle, a rectangle, and a trapezoid. In this investigation, seepage from circular and exponential sections ...
    • Flap Gate Design for Automatic Upstream Canal Water Level Control 

      Charles M. Burt; Russdon Angold; Mike Lehmkuhl; Stuart Styles (American Society of Civil Engineers, 2001)
      The EXCEL design procedure for a simple hydraulic flap gate for automatic upstream canal water level control is provided. Basic configurations were developed in The Netherlands in the 1920s and have recently been used in ...
    • Bentonite as an Ameliorant in an Alfisol—A Laboratory Study 

      P. K. Mishra; S. Siva Prasad; B. Maheswara Babu; L. R. Varalakshmi (American Society of Civil Engineers, 2001)
      Bentonite, a commercially available clay mineral, can be used for increasing the water holding capacity of the soil and as a sealant material. Laboratory studies were conducted with the amended soil using bentonite as an ...
    • Reduced-Runoff Irrigation of Alfalfa in Imperial Valley, California 

      K. M. Bali; M. E. Grismer; I. C. Tod (American Society of Civil Engineers, 2001)
      This paper assesses the potential of the “reduced-runoff” surface irrigation method for clay soils to limit tailwater runoff and evaluate its impacts on crop production and soil salinity throughout a 3-year alfalfa hay ...
    • Simulation of Water and Nitrogen Balances of Irrigated and Fertilized Corn-Crop Soil 

      Vassilis Z. Antonopoulos (American Society of Civil Engineers, 2001)
      Soil water and nitrogen dynamics under a corn-crop field in Northern Greece were simulated during the 1996 growing period and the subsequent noncropped period. The soil water and nitrogen simulations were evaluated using ...
    • EDR in Circular Channels 

      Subhasish Dey (American Society of Civil Engineers, 2001)
      This paper presents a simplified approach to determine the end depth of a free overfall in horizontal or mildly sloping circular channels. The flow over a free overfall in a circular channel is simulated by that over a ...
    • Parameter Identifiability for Three Sediment Entrainment Equations 

      Vicky L. Freedman; Vicente L. Lopes; Mariano Hernandez (American Society of Civil Engineers, 2001)
      A process-based erosion model is used to study parameterization problems of sediment entrainment equations in overland flow areas. One of the equations for entrainment by flow is developed based on a theory of excess stream ...
    • Irrigation Scheduling Using Mixed-Integer Linear Programming 

      Arif A. Anwar; Derek Clarke (American Society of Civil Engineers, 2001)
      A mixed-integer program is presented for scheduling canal irrigation among a group of users where the duration of flow of each outlet and a target start time is specified by the users. Two models are developed. The first ...