Multivariate dynamic modeling for Bayesian forecasting of business revenue

Forecasting enterprise-wide revenue is critical to many companies and presents several challenges and opportunities for significant business impact. This case study is based on model developments to address these challenges for forecasting in a large-scale retail company. Focused on multivariate revenue forecasting across collections of supermarkets and product categories, hierarchical dynamic models are natural: these are able to couple revenue streams in an integrated forecasting model, while allowing conditional decoupling to enable relevant and sensitive analysis together with scalable computation. Structured models exploit multi-scale modeling to cascade information on price and promotion activities as predictors relevant across categories and groups of stores. With a context-relevant focus on forecasting revenue 12 weeks ahead, the study highlights product categories that benefit from multi-scale information, defines insights into when, how, and why multivariate models improve forecast accuracy, and shows how cross-category dependencies can relate to promotion decisions in one category impacting others. Bayesian modeling developments underlying the case study are accessible in custom code for interested readers.     

Interactions and corrosion mitigation prospective of pyrazole derivative on mild steel in HCl environment

The effectiveness of 1H?pyrazole?3,5?dicarboxylic acid 5?benzyl ester 3?phenyl ester (PCBPE) as a preventer for deterioration of IS 513 Gr. D steel in 1 M HCl medium is evaluated via weight loss, electrochemical impedance, and polarization techniques. Kinetic and thermodynamic parameters assessed the feasibility of the adsorption process at diverse temperatures. The inhibition action on mild steel has been enhanced with increasing PCBPE concentration. It is found from the polarization studies that PCBPE behaves as mixed type inhibitor in HCl medium. The adsorption process of PCBPE on mild steel surface from acid environment is favoured Langmuir adsorption isotherm. The shielding efficiency of PCBPE has been enhanced at elevated concentrations, and it has been diminished at amplified temperatures. The Atomic Force Microscope (AFM), Scanning Electron Microscope (SEM), and Energy Dispersive Spectrum (EDS) were used to establish a surface characterization of metal specimens. A quantum chemical analysis of electron density distributions in the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) demonstrated how the inhibitor undergoes adsorption on mild steel in 1 M HCl. All experimental findings substantiate the corrosion mitigation performance of PCBPE on mild steel in acidic environments.     

Hydrothermal processing of waste pine wood into industrially useful products

An ongoing major outbreak of mountain pine beetle in Western Canada has provided a clear opportunity to utilize waste pinewood as a source of renewable energy. Therefore hydrothermal processing of waste pinewood as a feedstock for bio-oil and biochar production using subcritical and supercritical water technology was carried out in semi-batch mode to investigate the effect of pressure (200–400 bar) and temperature (300–400 °C) on the yield and composition of bio-oil. The pinewood samples have very high cellulose and hemicellulose content but low ash content and are thus a formidable feedstock for bioenergy production. The optimum conditions for the hydrothermal processing of the pinewood in a tubular reactor were found to be 400 °C and 250 bars with respect to biochar and bio-oil yield based on the highest calorific value analysis. Detailed characterization of bio-oil and biochar was performed using GCMS, NMR, SEM, calorific value, and elemental analysis, respectively. The critical components of bio-oil were found to be phenols, methoxyphenols, hydroxymethyl furfural (HMF), and vanillin, whereas as compared to the raw pine wood, the biochar was considerably lower H:C and O:C ratios than those of the unprocessed pinewood. The analyses of bio-oil by means of GCMS and ¹H NMR showed that it was mainly composed of heterocyclic compounds, phenols, aldehydes and acids.     

Hydrogen bonding interaction and topological insights of the electron localization/delocalization of l- arginine acetate

The vibrational spectral studies of the semi-organic material l- arginine acetate (LAA) are carried out with the help of density functional calculations to derive the equilibrium geometry as well as the vibrational wavenumbers and intensities of the spectral bands. The vibrational spectrum assignments are performed using normal coordinate analysis (NCA) in accordance with the scaled quantum mechanical force field approach (SQMFF). Vibrational spectra confirm the COO- modes split due to intra- and intermolecular association based on C–O….H, N–H….O, and O–H?O hydrogen bonding in the molecule, which lowers carboxylate wavenumbers. The natural bond orbital (NBO) analysis and DFT computations also confirm the occurrence of strong intra and intermolecular N–H?O and O–H?O ionic hydrogen bonding between charged species, providing the non-centrosymmetric structure in the LAA crystal.     

Role of Heterogeneous Chain Termination in Flame Propagation

Kinetics and Catalysis - The kinetic characteristics of propagating flame were shown to depend on the chemical properties of the contacting solid surface and on the rates of heterogeneous...     

Synthesis and Investigation of Piezophotocatalytic Properties of Polyvinylidene Fluoride Nanofibers Modified with Titanium Dioxide

Moscow University Chemistry Bulletin - A piezoactive nanofiber composite PVDF film with TiO2 nanoparticles included in it was synthesized by electrospinning. The composition, morphology and...     

ACID SODIUM SALT OF 1H-PYRAZOLE-3,4,5- TRICARBOXYLIC ACID: SYNTHESIS,CRYSTAL STRUCTURE AND FEATURES OF INTRAMOLECULAR BONDS

Journal of Structural Chemistry - The oxidation reaction of 3,3′,5,5′-tetramethyl-1H,1′H-4,4′-bipyrazole in the HNO3–Fe3+ system unexpectedly resulted in the formation...     

Kinetics of Absorption of Carbon Dioxide and Sulfur Dioxide in Fluorine-Containing Media

Kinetics and Catalysis - It has been established that the reactions of sulfur dioxide oxidation and carbon dioxide conversion take place in aqueous suspensions of calcium fluoride at room...     

Crystal growth,spectral characterization and structural studies of a luminescent coordination polymer of calcium(II) complex of benzilic acid

Single crystals of a new calcium(II) complex of benzilic acid, [Ca(C₁₄H₁₁O₃)₂(C₁₄H₁₂O₃)₂] have been successfully grown by gel diffusion technique at room temperature. Single crystal X-ray diffraction study reveals that the compound belongs to orthorhombic system with space group Fddd. The adjacent CaO₈ units are linked via O–H–O interaction to form one dimensional polymeric chains. The extensive hydrogen bonding interactions lead to a supramolecular structure. The grown crystals were further characterized by elemental analysis, FT-IR, UV–Visible, thermogravimetric, powder X-ray diffraction and solid state photoluminescence studies.     

Ionic and Phase Compositions of Y2.5Ce0.5Fe2.5Ga2.5O12 Ferrogarnet Powder Produced by Gel Combustion

Doklady Physical Chemistry - The ionic and phase compositions of Y2.5Ce0.5Fe2.5Ga2.5O12 ferrogarnet samples obtained by gel combustion with subsequent vacuum annealing were studied for the first...