A new algorithm for stope boundary optimization

Stopes can be simply defined as an underground opening from which ore has been excavated.Selection of the best combination of available stope boundary will directly affect the profitability of the operation.While a few attempts has been initiated to generate the optimum stope boundary for underground mining, they fail to guarantee a true optimality in three-dimension block models.This paper proposed a new methodology which can find optimum stope layout for a given resource model in three-dimensions.The p...     

Microencapsulated di-ammonium hydrogen phosphate (DAHP) with a polyurethane shell: characterization and its properties in wood

European Journal of Wood and Wood Products - This work deals with the microencapsulation of di-ammonium hydrogen phosphate (DAHP) in polyurethane using an interfacial polymerization method. The...     

Trace mineral profiles of the bivalve species Chamelea gallina and Donax trunculus

In this study, ICP-MS was used to determine concentrations of trace minerals found in these two economically important bivalvia species. Samples were collected from the Sea of Marmara in Turkey over a 12-month period in 2006–2007. The concentrations of Pb, Cu, Zn, Fe, Al, Mn, and Ni were significantly higher in Donax trunculus than in Chamelea gallina (p < 0.05). By contrast, Hg and Cd levels in C. gallina were significantly higher than in D. trunculus. Based on the limits set by the World Health Organization (WHO) and the Food and Agriculture Organization (FAO), our results suggest that these two species do not represent a risk for human consumption when the soft tissue is consumed with moderation. Highest arsenic concentrations of C. gallina and D. trunculus were found in spring samples (3.125 mg/kg and 3.669 mg/kg). Arsenic levels should be monitored in the future.     

Understanding student behavior and perceptions toward earning badges in a gamified MOOC

Universal Access in the Information Society - Despite the advantages of MOOCs, such as the open and free access to education, these courses are criticized for students’ lack of motivation and...     

A new model for open-pit production and waste-dump scheduling

An open-pit mine schedule defines the optimal sequence of mining valuable (ore) and waste material with the objective of maximizing the value of the project. Given this production schedule, a waste-dump schedule is then developed to determine the optimal waste-rock allocation in waste dumps. Thus, production and waste-dump schedules are managed separately, which leads to an inappropriate consideration of the material haulage cost, suboptimal schedules generating less value, and the incorrect classification of ore and waste. This article proposes a mixed-integer programming-based model that determines the optimal production and waste-rock dumping schedule concurrently with the objective of maximizing the discounted cash flow [net present value (NPV)] of the project. An implementation of the proposed model on a gold-mining operation outperforms the two existing methods [traditional and two-step mixed-integer programming (TSMIP) model] in the context of project NPV as well as its practicality.     

Effect of partial removal of prolamins on some chemical and functional properties of barley flours

In this study, some chemical and functional properties of hulled (BF-1) and hull-less (BF-2) barley flours and their partial prolamin removed forms (PPRF-1 and PPRF-2, respectively) were determined. Total dietary fiber and resistant starch values increased on dry weight basis, conversely β-glucan levels slightly decreased after partial prolamin removing (PPR). Sodium dodecyl sulphatepolyacrylamide gel electrophoresis (SDS-PAGE) patterns of PPRF-1 and PPRF-2 exhibited that PPR was highly achieved. Rapid visco analyzer (RVA) peak and breakdown viscosity values of PPRF-1 and PPRF-2 were higher than BF-1 and BF-2, conversely their setback, trough, and final viscosity values were lower than that of the BF-1 and BF-2, respectively. PPR also caused an increase in water binding capacity and resulted in a decrease on water solubility values of barley flours. Protein solubility of PPRF-1 and PPRF-2 were lower than BF-1 and BF-2, respectively. Emulsifying properties of PPRF-2 were affected negatively from the PPR.     

Spoilage and shelf life of sardines (Sardina pilchardus) packed in modified atmosphere

The effect of modified atmosphere packing (MAP) (O₂/CO₂/N₂, 5/35/60 (%) and O₂/CO₂/N₂, 5/70/25 (%)) on the quality of sardine stored in refrigerator was investigated in terms of sensory, chemical and microbiological analysis. Although chemical and microbiological analyses indicated that modified atmosphere packing prolonged the shelf life of sardine compared with that of air packing, sensory analysis showed that the extension of shelf life was (condition: O₂/CO₂/N₂, 5/70/25 (%)) 8 days and in air (condition: O₂/CO₂/ N₂, 5/35/60 (%)) 6 days. The results showed significant differences (p <0.05) between air and MAP storage conditions.     

Optimisation of antioxidant activity of grape cane extracts using response surface methodology

Solid–liquid extraction and response surface methodology were used to optimise conditions for the antioxidant activity of grape cane extracts. The independent processing variables were ethanol concentration, temperature and solvent to solid ratio. Ethanol concentration and temperature significantly affected antioxidant activity measured by the Trolox equivalent antioxidant capacity (TEAC) assay and the oxygen radical absorbance capacity using fluorescein (ORAC_FL) method (p  0.01), whereas the solvent to solid ratio did not significantly affect the activity (p > 0.05). Antioxidant activity of the extracts, determined by the TEAC assay, varied from 85.6 to 238.6 μmol Trolox equivalents/g of dry sample. ORAC_FL values ranged from 308.4 to 1302.7 μmol Trolox equivalents/g of dry sample. Ethanol concentrations of 40.4% and 55.4% were optimal for the highest antioxidant activities measured by the TEAC assay and the ORAC_FL method, respectively. The optimal temperature was 83.6 °C. Antioxidant activity correlates with total phenolic content of extracts.