Selected GAMS and or
Optimization Projects Done by Bruce McCarl
- Agricultural Sector Modeling - ASM
- Project Focus -- Sector model of US Agricultural Sector
- Type of Model -- Price endogenous nonlinear model of US Agricultural Sector for 70+ commodities in 63 US regions, versions include stochastic yields and world trade in seven commodities among 36 groups of countries
- Rough Model Size -- Version have in excess of 100,000 variables , 300 of which are nonlinear and 15,000 constraints
- Notes on Usage -- Model has been in heavy use for more than 20 years. Has been used to study effects of climate change, greenhouse gas mitigation, El Nino forecasting, conservation tillage, new cropping technology, pesticide bans and farm program revisions among numerous other applications. Related models have been built in Mali, Kenya, Egypt, Jordan, Guyana, and Nicaragua
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- Edwards Aquifer Water Management
- Project Focus -- Analysis of Water Allocation between Municipal, Industrial and Agricultural water users for the Edwards Aquifer Near San Antonio, Texas examining effects of allocation schemes on water prices, incomes, water use by party, pumping lift, aquifer elevation and spring flow under uncertain aquifer recharge
- Type of Model -- Price endogenous, nonlinear, stochastic programming with recourse, risk model
- Rough Model Size -- Has have in excess of 20,000 variables , 100 of which are nonlinear and 5,000 constraints
- Notes on Usage -- Model has been in use for more than 10 years. Has been used to study effects of water marketing, critical year irrigation interruption, proposed water allocation rules, regional conjunctive management and farm program revisions among other applications
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- Project Operating Funds Investment
- Project Focus -- A large state funded construction project was seeking the highest returning mix of securities in which to invest while meeting certain requirements for funding draws
- Type of Model -- Mixed integer profit maximizing model
- Rough Model Size -- Has in excess of 100 variables , 50 of which are integer and 40 constraints
- Notes on Usage -- Model was used by a bank to design a set of
securities that would give the highest ending cash level such that sufficient
securities matured in each time period so that the draws could be met. Bank
has set up an advertising brochure to model this capability to other project
agencies. Integer variables assure instruments are bought in relevant units.
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- Forestry Agriculture Land Exchange -- FASOM
- Project Focus --The possibility of reducing greenhouse gas
emissions has stimulated activity regarding moving agricultural lands into
forestry. This project evaluated the implications of such an effort
- Type of Model -- Nonlinear price endogenous 90 year model of forest and agricultural sectors
- Rough Model Size -- Has in excess of 100,000 variables and 30,000 constraints
- Notes on Usage -- Model was used to show that countervailing land movements of forest deintensification would occur under such a policy. Model has been used by USEPA and Forest Service to evaluate a number of other questions.
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- Meat Packing Plant Scheduling
- Project Focus -- A meat packing plant was scheduled for a week to maximize multiple objectives regarding profitability and inventories on hand
- Type of Model -- Mixed integer, multiple objective profit maximizing model
- Rough Model Size -- Has in excess of 5000 variables , 250 of which are integer and 800 constraints
- Notes on Usage -- Model was used to examine effects of revisions
in plant operating policies and equipment inventories. Integer variables
assure non interference of products in smokehouses.
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- Benefits to Salinity Control
- Project Focus -- A potential set of dams were appraised in terms of the economic benefits and environmental implications of their use for salinity control in the Red River
- Type of Model -- Profit maximizing LP model
- Rough Model Size -- Has in excess of 3000 variables and 400 constraints
- Notes on Usage -- Model was used to appraise agricultural profits stimulated by project construction.
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- Management of Texas Prison System Lands
- Project Focus --The Texas prison system stewards about 100,000 acres of land and uses agricultural product to feed 120,000 inmates. This study considered ways to improve management efficiency
- Type of Model -- Profit maximizing model with some mixed integer variants
- Rough Model Size -- Has in excess of 30,000 variables , and 7,000 constraints
- Notes on Usage -- Model used by prison system to evaluate profitability of operation, and implications of altering agricultural management or inmate diet.
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- Farm Planning and Machinery Management
- Project Focus -- A model was developed for direct farmer use in farm planning and machinery investment budgeting
- Type of Model -- Linear Program
- Rough Model Size -- Has in excess of 250 variables , and 140 constraints
- Notes on Usage -- Model was used by Extension Service, machinery companies and farmers to do and assist in planning. Was used by more than 5,000 farmers.
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- Milk Pricing and Distribution
- Project Focus -- A milk coop wanted to study implications of coop reorganization and structure for prices of member milk and milk movement
- Type of Model -- Linear profit maximizing model
- Rough Model Size -- Has in excess of 20,000 variables , and 2,000 constraints
- Notes on Usage -- Model was used to study alternative reconfiguration proposals.
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- El Nino Appraisal
- Project Focus -- NOAA wished to generate data on the potential value of improved forecasting of El Nino events
- Type of Model -- Price endogenous nonlinear model of US Agricultural Sector for 70+ commodities in 63 US regions, include stochastic yields from EL Nino and world trade in seven commodities among 36 groups of countries
- Rough Model Size -- Has in excess of 50,000 variables ,and 10,000 constraints
- Notes on Usage -- Model was used to generate appraisals of the Agricultural benefit of improved forecasting.
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- Biomass Fueled Power Plants
- Project Focus -- Fossil fuel emission reduction may make it desirable to use renewable fuels. This study examined the cost of renewable fuel use and the environmental implications.
- Type of Model --Nonlinear, price endogenous agriculture sector model
- Rough Model Size -- Has in excess of 20,000 variables ,and 4,000 constraints
- Notes on Usage --Model was used as input to Congressional deliberations regarding a biomass fuel initiative.
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