SABIIA - Sistema Aberto e Integrado de Informação em Agricultura (Sabiia)

Nicolson, Craig; Department of Natural Resources Conservation, University of Massachusetts, Amherst ; craign@eco.umass.edu; Berman, Matthew; Institute of Social and Economic Research, University of Alaska Anchorage; matthew.berman@uaa.alaska.edu; West, Colin Thor; Department of Anthropology, University of North Carolina at Chapel Hill ; ctw@email.unc.edu; Kofinas, Gary P.; Department of Humans and Environment and Institute of Arctic Biology, University of Alaska, Fairbanks ; gpkofinas@alaska.edu; Griffith, Brad; U.S. Geological Survey Alaska Cooperative Fish and Wildlife Research Unit; Institute of Arctic Biology University of Alaska Fairbanks; dbgriffith@alaska.edu; Russell, Don; CircumArtic Rangifer Monitoring and Assessment Network (CARMA); don.russell@ec.gc.ca; Dugan, Darcy; Alaska Ocean Observing System; dugan@aoos.org.

Livelihood systems that depend on mobile resources must constantly adapt to change. For people living in permanent settlements, environmental changes that affect the distribution of a migratory species may reduce the availability of a primary food source, with the potential to destabilize the regional social-ecological system. Food security for Arctic indigenous peoples harvesting barren ground caribou (Rangifer tarandus granti) depends on movement patterns of migratory herds. Quantitative assessments of physical, ecological, and social effects on caribou distribution have proven difficult because of the significant interannual variability in seasonal caribou movement patterns. We developed and evaluated a modeling approach for simulating the distribution...

Tipo: Peer-Reviewed Reports

Palavras-chave: Caribou; Markovian; Migration; Rangifer tarandus granti; Seasonal distribution; Simulation; Subsistence hunting.

Ano: 2013

Improving Participatory Processes through Collective Simulation: Use of a Community of Practice

Dionnet, Mathieu; Lisode; mathieu.dionnet@lisode.com; Daniell, Katherine A; Centre for Policy Innovation, The Australian National University; katherine.daniell@anu.edu.au; Imache, Amar; Lisode; amar.imache@lisode.com; von Korff, Yorck; Lisode; yorck.von-korff@lisode.com; Bouarfa, Sami; UMR G-EAU, Cemagref; sami.bouarfa@cemagref.fr; Garin, Patrice; UMR G-EAU, Cemagref; patrice.garin@cemagref.fr; Jamin, Jean-Yves; UMR G-EAU, CIRAD; jamin@cirad.fr; Rollin, Dominique; UMR G-EAU, Cemagref; dominique.rollin@cemagref.fr; Rougier, Jean-Emmanuel; Lisode; Jean-Emmanuel.Rougier@lisode.com.

Tipo: Peer-Reviewed Reports

Palavras-chave: Community of practice; Natural resource management; Public participation; Role play; Simulation.

Ano: 2013

A Fractal Landscape Realizer for Generating Synthetic Maps

Hargrove, William; Oak Ridge National Laboratory; hnw@fire.esd.ornl.gov; Hoffman, Forrest M; Oak Ridge National Laboratory;; Schwartz, Paul M; ;.

A fractal landscape realizer has been developed that generates synthetic landscape maps to user specifications. The alternative landscape realizations are not identical to the actual maps after which they are patterned, but are similar statistically (i.e., the areas and fractal character of each category are replicated). A fractal or self-affine pattern generator is used to provide a spatial probability surface for each category in the synthetic map. The Fractal Realizer arbitrates contentions among categories in a way that makes it possible to preserve the fractal patterns of all the categories in the resulting synthetic landscape. Each synthetic landscape is one equally likely realization from among an infinite ensemble of possible fractal landscape...

Tipo: Peer-Reviewed Reports

Palavras-chave: FRAGSTATS; Fractal Realizer; Turing Test; Categorical maps; Fractal; Landscape ecology; Neutral model; Null model; Pattern; Pseudoreplication; Realization; Simulation; Synthetic map.

Ano: 2002

Modeling the Effects of Land Use on the Quality of Water, Air, Noise, and Habitat for a Five-County Region in Georgia

Dale, Virginia H; ; dalevh@ornl.gov; Akhtar, Farhan; Georgia Institute of Technology;; Aldridge, Matthrew; University of Tennessee;; Baskaran, Latha; Oak Ridge National Laboratory;; Berry, Michael; University of Tennessee;; Browne, Murray; University of Tennessee;; Chang, Michael; Georgia Institute of Technology;; Efroymson, Rebecca; Oak Ridge National Laboratory;; Garten, Jr., Charles; Oak Ridge National Laboratory;; Lingerfelt, Eric; University of Tennessee;; Stewart, Catherine; Aberdeen Proving Ground;.

A computer simulation model, the Regional Simulator (RSim), was constructed to project how land-use changes affect the quality of water, air, noise, and habitat of species of special concern. RSim was designed to simulate these environmental impacts for five counties in Georgia that surround and include Fort Benning. The model combines existing data and modeling approaches to simulate the effects of land-cover changes on: nutrient export by hydrological unit; peak 8-h average ozone concentrations; noise caused by small arms and blasts; and habitat changes for the rare Red-cockaded Woodpecker (Picoides borealis) and gopher tortoise (Gopherus polyphemus). The model also includes submodules for urban growth, new urbanization influenced by existing roads,...

Tipo: Peer-Reviewed Reports

Palavras-chave: Gopher tortoise; Land use; Landscape change; Longleaf pine; Nutrient export; Red-cockaded Woodpecker; Simulation.

Ano: 2008

Challenges in adaptive management of riparian and coastal ecosystems

Walters, Carl; University of British Columbia; c.walters@fisheries.ubc.ca.

Many case studies in adaptive-management planning for riparian ecosystems have failed to produce useful models for policy comparison or good experimental management plans for resolving key uncertainties. Modeling efforts have been plagued by difficulties in representation of cross-scale effects (from rapid hydrologic change to long-term ecological response), lack of data on key processes that are difficult to study, and confounding of factor effects in validation data. Experimental policies have been seen as too costly or risky, particularly in relation to monitoring costs and risk to sensitive species. Research and management stakeholders have shown deplorable self-interest, seeing adaptive-policy development as a threat to existing research programs and...

Tipo: Peer-Reviewed Reports

Palavras-chave: Adaptive management; Coastal ecosystems; Ecosystem management; Fisheries; Institutional barriers; Management experiments; Modeling; Riparian ecosystems; Simulation.

Ano: 1997

Managing the Resilience of Lakes: A Multi-agent Modeling Approach

Janssen, Marco A; Indiana University; maajanss@indiana.edu; Carpenter, Stephen R; University of Wisconsin-Madison; srcarpen@wisc.edu.

We demonstrate an approach for integrating social and ecological models to study ecosystem management strategies. We focus on the management of lake eutrophication. A model has been developed in which the dynamics of the lake, the learning dynamics of society, and the interactions between ecology and society are included. Analyses with the model show that active learning is important to retain the resilience of lakes. Although very low levels of phosphorus in the water will not be reached, active learning reduce the chance of catastrophic high phosphorus levels.

Tipo: Peer-Reviewed Reports

Palavras-chave: Active learning; Eutrophication; Integrated modeling; Lake dynamics; Lake management; Multi-agent modeling; Phosphorus; Resilience; Restoration; Simulation.

Ano: 1999

Mechanisms Affecting Population Density in Fragmented Habitat

Tischendorf, Lutz; ELUTIS Modelling and Consulting Inc.; lutz.tischendorf@gmx.net; Grez, Audrey; Universidad de Chile; agrez@uchile.cl; Fahrig, Lenore; Carleton University; lfahrig@ccs.carleton.ca.

We conducted a factorial simulation experiment to analyze the relative importance of movement pattern, boundary-crossing probability, and mortality in habitat and matrix on population density, and its dependency on habitat fragmentation, as well as inter-patch distance. We also examined how the initial response of a species to a fragmentation event may affect our observations of population density in post-fragmentation experiments. We found that the boundary-crossing probability from habitat to matrix, which partly determines the emigration rate, is the most important determinant for population density within habitat patches. The probability of crossing a boundary from matrix to habitat had a weaker, but positive, effect on population density. Movement...

Tipo: Peer-Reviewed Reports

Palavras-chave: Boundary crossing; Emigration; Habitat fragmentation; Immigration; Modeling; Movement; Population density; Simulation; Time scale.

Ano: 2005

Adaptive Harvesting in a Multiple-Species Coral-Reef Food Web

Kramer, Daniel B; Michigan State University; dbk@msu.edu.

The utility of traditional bio-economic harvest models suffers from their dependence on two commonly used approaches. First, optimization is often assumed for harvester behavior despite system complexity and the often neglected costs associated with information gathering and deliberation. Second, ecosystem interactions are infrequently modeled despite a growing awareness that these interactions are important. This paper develops a simulation model to examine the consequences of harvesting at two trophic levels in a coral-reef food web. The model assumes adaptive rather than optimizing behavior among fishermen. The consequences of changing economic, biological, and social parameters are examined using resilience as an evaluative framework. Three general...

Tipo: Peer-Reviewed Reports

Palavras-chave: Fisheries; Resource economics; Coral reefs; Resilience; Adaptive behavior; Food web; Simulation.

Ano: 2008

DEFORMATION OF PEACHES SUBMITTED TO CYCLIC LOADING USING THE DISCRETE ELEMENT METHOD

Pinto,Eduardo M.; Ferraz,Antonio C. de O..

ABSTRACT This study aimed to use and validate a simple contact force model that describes the behavior of peaches stored in a wooden box, loaded cyclically, by using the discrete element method. The Kelvin-Voigt contact force model was used and the cyclic loading in the simulation was performed with an amplitude of 1 mm and frequency of 12 Hz for time intervals of 3600, 5400, and 7200 s. The laboratory test was performed with a peach box attached to a vibrating table by applying the same excitation conditions used in the simulation. For validation, model results were compared with those from the laboratory test by using deformation values of fruits in the contact regions. To measure this deformation, we adapted the methodology for determining the radius of...

Application of simulated annealing in simulation and optimization of drying process of Zea mays malt

Palavras-chave: Modeling; Simulation; Post-harvest; Prunus persica (L.) Batsch.

Ano: 2018

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162018000300434

Benvenga,Marco A. C.; Araújo,Sidnei A. de; Librantz,André F. H.; Santana,José C. C.; Tambourgi,Elias B..

Kinetic simulation and drying process optimization of corn malt by Simulated Annealing (SA) for estimation of temperature and time parameters in order to preserve maximum amylase activity in the obtained product are presented here. Germinated corn seeds were dried at 54-76 °C in a convective dryer, with occasional measurement of moisture content and enzymatic activity. The experimental data obtained were submitted to modeling. Simulation and optimization of the drying process were made by using the SA method, a randomized improvement algorithm, analogous to the simulated annealing process. Results showed that seeds were best dried between 3h and 5h. Among the models used in this work, the kinetic model of water diffusion into corn seeds showed the best...

Mechanical properties of grain in silos for simulation designs

Palavras-chave: Simulated annealing; Zea mays; Drying curves; Optimization; Simulation.

Ano: 2011

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162011000500012

Lopes Neto,José P.; Nascimento,José W. B. do; Marques,Jordânio I.; Costa,Carlos A. da.

ABSTRACT For the calculation of silos structures it has been used new methods and computational tools that require mechanical properties knowledge that are still unknown for most storable materials, especially grains. In this context, we aimed to determine the mechanical properties of rice and beans grains with moisture contents of 10, 12, and 14% by applying four compressive loads (5, 10, 15 and 20). The determined mechanical properties were Poisson's ratio (ν), Modulus of Elasticity (E), and the dilatancy angle (ψ). The procedure consisted in the application of the load in compression cell, adapted from MOLENDA & STASIAK, aiming to simulate loading and unloading of silos. We observed that the Poisson's ratio calculated for both loading and unloading,...

NEURO-FUZZY MODELING OF EYEBALL AND CREST TEMPERATURES IN EGG-LAYING HENS

Palavras-chave: Poisson’s coefficient; Compression; Modulus of elasticity; Silos; Simulation.

Ano: 2016

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162016000400573

Lins,Ana C. de S. S.; Lourençoni,Dian; Yanagi Júnior,Tadayuki; Miranda,Isadora B.; Santos,Italo E. dos A..

ABSTRACT Considering the challenges faced by poultry farming, this study aimed to develop a neuro-fuzzy model to predict eyeball and crest temperatures of egg-laying hens based on environmental conditions (dry bulb temperature and relative humidity). To develop the models and simulations, Matlab’s Fuzzy Toolbox® (Anfisedit) was used. Different configurations were used for each of the several neuro-fuzzy models developed. Eyeball temperature (ET) and chicken crest temperature (CCT) were simulated from the developed neuro-fuzzy models, and the obtained results were validated with the variables collected experimentally with the aid of recorder sensors and an infrared thermographic camera. The proposed neuro-fuzzy models allow the accurate estimation of ET and...

Computer tools applied to analysis of solar water heaters

Palavras-chave: Neuro-fuzzy; Thermography; Poultry farming; Simulation; Artificial intelligence.

Ano: 2021

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162021000100034

Altoé,Leandra; Oliveira Filho,Delly; Carlo,Joyce C.; Monteiro,Paulo Marcos de B..

The simulation programs are important tools to analyze the different energetic alternatives, including the use of renewable energy. The objective of this study was to analyze comparatively the different computer tools available for modeling of solar water heaters. Among the main simulation software of solar thermal systems, there are: RETScreen International, EnergyPlus, TRNSYS, SolDesigner, SolarPro, e T*SOL. Among the tools mentioned, only EnergyPlus and RETScreen International are free, but they allow obtaining interesting results when applied together. The first one has a detailed module of energy analysis of solar water heaters, while the second one provides an detailed economic feasibility study and an assessment of emissions of greenhouse gases....

CALIBRATION AND TESTING OF CS-CROPGRO MODEL FOR COMMON BEANS

Palavras-chave: Simulation; Solar energy; Water heating.

Ano: 2013

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162013000500018

Santos,Miquéias G. Dos; Faria,Rogério T. De; Palaretti,Luiz F.; Dantas,Geffson De F.; Dalri,Alexandre B.; Lopes,Adriano Da S..

ABSTRACT: Simulation models of crop growth enable estimating crop yield and water balance components with low cost and high precision. This study aimed to calibrate and evaluate the performance of the CS-CROPGRO model for common beans under the conditions of Jaboticabal city (SP), Brazil. The model was calibrated and tested with data previously collected from two experiments conducted in 2002 and 2003. In these experiments, treatments corresponded to two irrigation scheduling methods (tensiometers and class A pan evaporation) and two cropping systems (conventional and no-till). For calibration, data from the experiment carried out in 2002 were used. For testing, we used data from the experiment conducted in 2003. By using the genetic coefficients...

VALIDATION OF A HEATING SYSTEM IN THE FARROWING HOUSE USING A CFD APPROACH

Palavras-chave: Simulation; DSSAT; Phaseolus vulgaris; Irrigation; Planting system.

Ano: 2016

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162016000601239

Damasceno,Flávio A.; Oliveira,Carlos E. A.; Saraz,Jairo A. O.; Schiassi,Leonardo; Oliveira,Jofran L. de.

ABSTRACT The current heating system for piglets in the farrowing usually uses incandescent lamps and, in some cases, heated floors with electric resistances, which in most cases generates a high energy cost. Thus, the implantation of systems that use renewable energies in the heating of piglets can allow the thermal comfort of the animals without reducing the productive development. The objective of this research was to evaluate a computer model in Computational Fluid Dynamics (CFD), which predicts surface temperature in the heating system of a farrowing house. The study was conducted during the summer season on the swine sector of Federal University of Lavras, Brazil. For this study, a prototype solar heater using alternative materials (ASWH) was...

A DISCRETE STOCHASTIC MODEL TO DETERMINE FOOD QUALITY BY USING SIMULATION: A STRAWBERRY CASE STUDY

Palavras-chave: Swine; Computational modelling; Simulation.

Ano: 2018

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162018000400471

González-Hernández,Isidro J.; Granillo-Macías,Rafael; Rondero-Guerrero,Carlos; Martínez-Flores,José L..

ABSTRACT The agri-food supply chain (AFSC) sets a series of challenges in the production, storage, distribution, and transportation processes, as the market's requirements for fresh food combine food quality and safety attributes. This research suggests a discrete event modeling to study the behavior of food quality in all supply chains (SCs) in terms of temperature and time variables in a stochastic manner. The ProModel software was used to simulate strawberry quality in the SC, considering a distribution route to export the fruit from Mexico to the United States. The suggested model together with a computer simulation analyzes the fruit quality from two perspectives: with and without a cold chain (CC). The obtained results revealed that in the case of CC...

Effects of maintenance management procedures in sugarcane mechanic harvesting system equipment

Palavras-chave: Agri-food supply chain; Discrete and stochastic model; Food quality; Simulation.

Ano: 2020

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162020000600747

Faria,Luís F. F.; Silva,João E. A. R..

ABSTRACT The aim of this study was to evaluate the effects of modifying the maintenance programming of equipment used in sugarcane mechanical harvesting, by transferring actions that can be planned to periods when machines are inactive due to meal breaks and other working shift transitions stoppages. A simulation model was developed to represent the maintenance procedures of combines, haulouts, and other vehicles used by a harvest team. Scenarios were tested using alternatives for interventions such as refueling, lubrication and harvester blade replacement, enabling strategies to be focused towards better utilization of cutting, loading, and transport (CLT) system equipment. As a result, it was possible to remove one combine and two haulouts, while...

Estimating the effects of population size and type on the accuracy of genetic maps

Palavras-chave: Agricultural machinery; Breakdowns; Simulation.

Ano: 2015

URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162015000601187

Genet. Mol. Biol.

Ferreira,Adésio; Silva,Marcia Flores da; Silva,Luciano da Costa e; Cruz,Cosme Damião.

Based on simulation studies, it was shown that the type and size of experimental populations can exert an influence on the accuracy of genetic maps. A hypothetical genome map (one chromosome with nine equidistant molecular markers) was generated for the following population types: F2 with dominant and co-dominant markers, backcrossing, recombinant inbred lines (RIL) and double-haploid. The population sizes were 50, 100, 150, 200, 500 and 1000 individuals and 100 simulations were made for each population. The inaccuracies of the populations with the lowest number of individuals were shown by inversions in the order of the markers and the establishment of more than one linkage group in up to 38% of the simulations, depending on the population type. Stress...