| 1. |
- Ahmed, Faisal, et al.
(författare)
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Machine Learning-Based Tomato Leaf Disease Diagnosis Using Radiomics Features
- 2023
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Ingår i: Proceedings of the Fourth International Conference on Trends in Computational and Cognitive Engineering - TCCE 2022. - : Springer Science and Business Media Deutschland GmbH. - 9789811994821 - 9789811994838 ; , s. 25-35
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Konferensbidrag (refereegranskat)abstract
- Tomato leaves can be infected with various infectious viruses and fungal diseases that drastically reduce tomato production and incur a great economic loss. Therefore, tomato leaf disease detection and identification are crucial for maintaining the global demand for tomatoes for a large population. This paper proposes a machine learning-based technique to identify diseases on tomato leaves and classify them into three diseases (Septoria, Yellow Curl Leaf, and Late Blight) and one healthy class. The proposed method extracts radiomics-based features from tomato leaf images and identifies the disease with a gradient boosting classifier. The dataset used in this study consists of 4000 tomato leaf disease images collected from the Plant Village dataset. The experimental results demonstrate the effectiveness and applicability of our proposed method for tomato leaf disease detection and classification.
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| 2. |
- Arismendi Arrieta, Daniel Jose, et al.
(författare)
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H2O2(s) and H2O22H2O(s) crystals compared with ices : DFT functional assessment and D3 analysis
- 2023
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Ingår i: Journal of Chemical Physics. - : American Institute of Physics (AIP). - 0021-9606 .- 1089-7690. ; 159:19
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Tidskriftsartikel (refereegranskat)abstract
- The H2O and H2O2 molecules resemble each other in a multitude of ways as has been noted in the literature. Here, we present density functional theory (DFT) calculations for the H2O2(s) and H2O2·2H2O(s) crystals and make selected comparisons with ice polymorphs. The performance of a number of dispersion-corrected density functionals—both self-consistent and a posteriori ones—are assessed, and we give special attention to the D3 correction and its effects. The D3 correction to the lattice energies is large: for H2O2(s) the D3 correction constitutes about 25% of the lattice energy using PBE, much more for RPBE, much less for SCAN, and it primarily arises from non-H-bonded interactions out to about 5 Å.The large D3 corrections to the lattice energies are likely a consequence of several effects: correction for missing dispersion interaction, the ability of D3 to capture and correct various other kinds of limitations built into the underlying DFT functionals, and finally some degree of cell-contraction-induced polarization enhancement. We find that the overall best-performing functionals of the twelve examined are optPBEvdW and RPBE-D3. Comparisons with DFT assessments for ices in the literature show that where the same methods have been used, the assessments largely agree.
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| 3. |
- Sen, Anik, et al.
(författare)
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H-bond and electric field correlations for water in highly hydrated crystals
- 2016
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Ingår i: International Journal of Quantum Chemistry. - : Wiley. - 0020-7608 .- 1097-461X. ; 116:2, s. 67-80
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Tidskriftsartikel (refereegranskat)abstract
- We present periodic plane-wave density functional theory (DFT) Perdew-Burke-Ernzerhof (PBE-D2) calculations for four highly hydrated crystals, Na2CO3 center dot 10H(2)O, MgSO4 center dot 7H(2)O, MgSO4 center dot 11H(2)O, and Al(NO3)(3)center dot 9H(2)O, containing 37 structurally unique water molecules and 74 unique hydrogen bonds. The calculated R(H center dot center dot center dot O) distances lie in the range 1.60-2.05 angstrom, the anharmonic OH frequencies in the range 2570-3425 cm(-1), and the water dipole moments lie in the range 2.9-4.3 Debye, as calculated from the Wannier function centers and the nuclei. We present the following findings. (i) Our optimized intramolecular r(OH) distances are always larger than the gasphase value and thus more accurate than those derived from neutron diffraction experiments; (ii) The local in situ electric field over the molecule, calculated from the positions of the nuclei and the Wannier centers in the surrounding crystal, appears to be a good descriptor of the pertturbation from the water molecule's surroundings as the internal molecular properties (r(e), nu, mu) are found to correlate well with the crystal-generated electric field; (iii) We have added DFT-calculated data points to the well-known experimental 'OH frequency versus R(H center dot center dot center dot O) correlation curve in a region where the experimental data points are scarce; (iv) For all 37 water molecules, the Wannier centers located in the lone-pair region, and those located in the OH bonds, displace about equally much due to the polarizing environment. Finally, we propose that our resulting 'OH frequency versus Wannier-type electric field' correlation curve may constitute a useful tool for predicting OH vibrational frequencies from snapshots from PBE-D2-based ab initio molecular dynamics simulations of water-containing systems.
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