الفهرس 
Definitions of expert systemOnly 14 pages are availabe for public view
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Abstract
As a result of increasing demands on limited water
resources, there is a critical need for proper irrigation
management. The most fundamental requirement of irrigation
scheduling as a part of efficient irrigation management is the
estimation of actual crop evapotranspiration (ETa). But the
complexity of estimating actual crop evapotranspiration
precisely makes using software programs such as the expert
systems necessary for effective decision-making support in this
domain.
A. Objectives of this study were:
1. Build, verify and validate an expert system for managing
on-farm irrigation water of some oil crops under Egyptian
conditions.
2. Evaluate the precision of dual-Kc approach for estimating
daily actual crop evapotranspiration (ETa) and compare it
with the single-Kc approach.
3. Study the effect of the precise estimation of daily actual
crop evapotranspiration on maximizing yield and
improving water use efficiency.
B. The material and methods used in this work can be
summarized as following:
1. A rule-based program named IMOC-ES (Irrigation
Management for some Oil Crops-Expert System) was
coded and compiled using Microsoft visual basic 2013
language. The study presented the proposed program with
its components, the built up reference information (location
information, soil properties, climatic data, crop data, and irrigation options) and all equations as well as rules used
for estimating irrigation water management parameters.
2. The IMOC-ES rule-based program was verified using two
ready-to-use software programs (CropWat-8 and ETo
Calculator-3.2) for estimating the daily reference
evapotranspiration ( ETo ) and a spreadsheet named
(FAO56Ax8.xls) introduced by FAO-56 for estimating the
irrigation water management parameters.
3. The IMOC-ES rule-based program was validated by
carrying out a field experiment at the Experimental Farm of
Agricultural Production and Research Station (APRS),
National Research Centre (NRC), El Nubaria District, ElBehaira Governorate, Egypt for a growing summer season
of 2014. An automatic drip irrigation system was set up to
apply the irrigation depth needed by plants precisely and
at the proper time.
4. The experiment included the following factors:
Two approaches for estimating crop evapotranspiration
(single-Kc and dual-Kc),
Two irrigation systems (surface drip irrigation and
subsurface drip irrigation), and
Two oil seed crops (peanut and sesame).
The obtained results showed that:
1. The reference evapotranspiration ( ETo ) calculated using
IMOC-ES rule-based program gave a high agreement
among the values obtained from both CropWat-8.0 and ETo
Calculator-3.2 programs.2. The all calculated equations using IMOC-ES rule-based
gave a high correlation with those obtained from the FAO-
56 spreadsheet (FAO56Ax8.xls).
3. The estimation of actual crop evapotranspiration (ETa)
using dual-Kc approach is more accuracy compared with
the single-Kc approach.
4. The seasonal cumulative ETa estimated by dual-Kc
approach overestimated that estimated by single-Kc
approach under surface drip irrigation by 13.20 % for
peanut and 21.90 % for sesame. While under sub-surface
drip irrigation, the dual-Kc approach overestimated the
single-Kc approach by 4.42 % for peanut and 17.64 % for
sesame.
5. Yield: the highest yields of peanut (2.23 ton fed-1) and
sesame (0.66 ton fed-1) were obtained with the interaction
(sub-surface drip irrigation × dual-Kc) and the other
interactions could be written as:
Surface drip irrigation × control < sub-surface drip
irrigation × control < surface drip irrigation × singleKc < sub-surface drip irrigation × single-Kc < surface
drip irrigation × dual-Kc.
6. Water use efficiency: maximum value of WUE for peanut
(0.66 Kg m-3) and sesame (0.23 Kg m-3) recorded with the
interaction (sub-surface drip irrigation × dual-Kc) and the
other interactions could be arranged as:
Surface drip irrigation × control < sub-surface drip
irrigation × control < surface drip irrigation ×
single-Kc < surface drip irrigation × dual-Kc < subsurface drip irrigation × single-Kc.The recommendations of this study:
1. The possibility of using the IMOC-ES rule-based
program for estimating the irrigation requirements
precisely when daily weather data become available
without significant differences from those estimated by
hand.
2. The suggested program is the first one in Egypt to
estimate the actual evapotranspiration using dual-Kc
approach according to the daily weather data.
3. The precise estimation of actual crop
evapotranspiration can maximize yield and improve
water use efficiency under the same conditions.