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A two-dimensional constitutive model was developed to simulate grain boundary motion in polycrystalline titanium exposed simultaneously to magnetic field and elastic strain based on the thermodynamic laws. The multi-scale coupled finite element and multi-phase-field simulations were used to investigate the simultaneous effects of the driving forces arising from the magnetic field and elastic strain energy on microstructure evolution of titanium bicrystalline and polycrystalline samples. The multi-phase-field approach was employed to implement the kinetic relations of grain boundary migration at the mesoscale level. On the other hand, the equilibrium equations were implemented on a macroscale level by the finite element method. Based on the simulation results, the magnetically induced driving force overrides the elastic strain driving force and causes texture evolution toward orientations that contain less magnetic stored energy when the microstructure is exposed to a magnetic field of sufficient strength. Additionally, applying an elastic strain before annealing reduces the time required for magnetic field annealing by accelerating the microstructure evolution. The mean grain size and desired texture grow rapidly when the magnetic field strength and elastic strain are simultaneously increased. [ABSTRACT FROM AUTHOR]

[Display omitted] • Thermodynamically consistent multiphase field theory for magnetic field-induced grain boundary migration. • Quantitative simulations of magnetic field-induced grain growth in polycrystalline titanium. • Investigating the effects of intensity and direction of magnetic field on grain growth kinetics. A constitutive model for diffuse interface description of magnetic field-induced grain boundary migration in polycrystalline metals is developed based on the laws of thermodynamics. Within this phase field modeling framework, simultaneous minimization of the total grain boundary energy and the stored magnetic energy within grains provides the driving force for grain growth in a polycrystal material exposure to a magnetic field. Using the available experimental data, phase field simulations of magnetic field induced grain growth in bicrystalline zinc and polycrystalline titanium with two-dimensional columnar microstructure are performed and the model is validated by demonstrating a qualitative and quantitative match with experimental data. Using the validated constitutive model, the effects of magnetic field intensity and direction on evolution of microstructure and polycrystalline texture in titanium are investigated. Quantitative simulation results show that under certain magnetic field directions and sufficient magnetic field intensity, the magnetic energy minimizing driving force can overcome the curvature driving force and cause texture evolution towards less magnetic energy grain orientations during annealing. However, magnetic fields with insufficient intensity or improper direction have negligible effect on grain coarsening by nearly normal grain growth. The desired magnetic field direction and intensity are quantitatively presented for cold-rolled and annealed sheet titanium samples. [ABSTRACT FROM AUTHOR]

Classification of vegetation according to their species composition is one of the most important tasks in the application of remote sensing in precision agriculture. To prepare an algorithm for such a mandate, there is a need for ground truth. Field operation is very costly and time consuming. Therefore, some other method must be developed, such as extracting information from the satellite images, which is comparatively cheaper and faster. In this study, we first introduced a simple method for Determination of the Vegetation Specie in full cover pixels (DVS) using their laboratory measured spectral reflectance curves. Then, based on these pixels, a hybrid method for vegetation field classification, which we call SCANN (Spectral Characteristics and Artificial Neural Network), is introduced. In this method, different vegetation spectral reflectance characteristics at the three extremes of green, red, and near-infrared along with an artificial neural network method were used. Comparing the results of DVS with those of field collected data showed near 100% accuracy. Based on the results of DVS, the results of SCANN showed an overall accuracy of more than 94%. This method is suggested for unsupervised classification using Hyperspectral images. [ABSTRACT FROM AUTHOR]

Classification of vegetation according to their species composition is one of the most important tasks in the application of remote sensing in precision agriculture. To prepare an algorithm for such a mandate, there is a need for ground truth. Field operation is very costly and time consuming. Therefore, some other method must be developed, such as extracting information from the satellite images, which is comparatively cheaper and faster. In this study, we first introduced a simple method for Determination of the Vegetation Specie in full cover pixels (DVS) using their laboratory measured spectral reflectance curves. Then, based on these pixels, a hybrid method for vegetation field classification, which we call SCANN (Spectral Characteristics and Artificial Neural Network), is introduced. In this method, different vegetation spectral reflectance characteristics at the three extremes of green, red, and near-infrared along with an artificial neural network method were used. Comparing the results of DVS with those of field collected data showed near 100% accuracy. Based on the results of DVS, the results of SCANN showed an overall accuracy of more than 94%. This method is suggested for unsupervised classification using Hyperspectral images. [ABSTRACT FROM AUTHOR]

Background: The date palm cultivation has a long history in Bushehr province. Throughout the recent decade; the dusts, in addition to direct harmful effects on humans, have adverse effects on health of the population living in this area. The infestation of pests in the southern province of Bushehr has groves. Due to the importance of dates in this area, the total ash and acid insoluble ash as indexes for assessing of chemical pollution and also, mold and yeast as indicators for microbial contamination were evaluated. Recently in a number of dates packaging industries, washing the products after the harvest is done. In current study, the effects of rinsing to decrease the dust pollution on date palm along with, the time effect on the quality and durability of washed and un-washed dates were investigated. Materials and Methods: Overall, 48 washed and un-washed dates were sampled from traditional and technologically advanced packaging industries, equally, and were confirmed according to ISIRI methods. Results: The Averages of total and acid insoluble ashes in washed date samples were:1.05±0.14 and 3.32±0.32%, and for un-washed samples were 1.36±0.27 and 4.59±1.64 percent, respectively. In all date samples were presented the yeast, however, their means were lower than the maximum limit (1 x 104 CFU). Also, all date samples were moldy. The Mean percentage of total ash samples in un-rinsed and rinsed dates were approximately, 1.84 and 1.33 times more than the maximum permissible limit, respectively. The mean of acid insoluble ash in all samples (100%), and 98% of total ash were higher than acceptable levels (p<0.05). The results revealed that the average percentage difference between the two groups were transpicuous, while this difference was not significant (p=0.13). Under the similar conditions, the average amount of yeast in washed date samples, were significantly different (p<0.05) and more than un-wash samples. The Mold levels in un-rinsed and rinsed samples; were 83.3 and 75% higher than the maximum permissible limit. According to the results, regardless of a decrease in amount of molds in washed samples than un-wash samples, the rinsing, was unable to eliminate the pollution, or even decreased it to acceptable levels. Conclusion: According to the findings, present rinsing is not an appropriate method for long storage. Observations, after one year upkeep in the same conditions, expressed that all un-washed date samples were apparently healthy, without any pests and insects. While 91.6% of the washed samples were insectivores, also their textured appearances were very unpleasant. [ABSTRACT FROM AUTHOR]