•Systematic analysis of preprocessing parameters are reported for grape and wine spectra.•Two attributes from Cabernet Sauvignon wines were predicted by grape MIR consistently across three ...vintages.•Two attributes from Chardonnay wines were predicted by wine MIR consistently across two vintages.•Using MIR as a rapid and indicative predictor of wine style is an optimistic feat.•The ability of MIR to predict sensory properties with high accuracy remains challenging.
The study determined optimal parameters to four preprocessing techniques for mid-infrared (MIR) spectra of wines and grape berry homogenates and tested MIR’s ability to model sensory properties of research Cabernet Sauvignon and Chardonnay wines. Savitsky-Golay (SG) derivative, smoothing points, and polynomial order, and extended multiplicative signal correction (EMSC) polynomial were investigated as preprocessing techniques at 2, 2, 5, and 3 levels, respectively, all in combination. Preprocessed data were analysed with partial least squares regression (PLS) to model the wine sensory data and the regression coefficients of PLS calibration models (R2) were further analysed with multivariate analysis of variance (MANOVA). SG transformations were significant factors from the MANOVA that influenced R2, while EMSC did not. Overall, PLSR models that predicted wine sensory characteristics gave a poor to moderate R2. Consistently predicting wine sensory attributes within a variety and across vintages is challenging, regardless of using grape or wine spectra as predictors.
Coagulation–flocculation is a relatively simple physical–chemical technique in treatment of old and stabilized leachate which has been practiced using a variety of conventional coagulants. Polymeric ...forms of metal coagulants which are increasingly applied in water treatment are not well documented in leachate treatment. In this research, capability of poly-aluminum chloride (PAC) in the treatment of stabilized leachate from Pulau Burung Landfill Site (PBLS), Penang, Malaysia was studied. The removal efficiencies for chemical oxygen demand (COD), turbidity, color and total suspended solid (TSS) obtained using PAC were compared with those obtained using alum as a conventional coagulant. Central composite design (CCD) and response surface method (RSM) were applied to optimize the operating variables viz. coagulant dosage and pH. Quadratic models developed for the four responses (COD, turbidity, color and TSS) studied indicated the optimum conditions to be PAC dosage of 2
g/L at pH 7.5 and alum dosage of 9.5
g/L at pH 7. The experimental data and model predictions agreed well. COD, turbidity, color and TSS removal efficiencies of 43.1, 94.0, 90.7, and 92.2% for PAC, and 62.8, 88.4, 86.4, and 90.1% for alum were demonstrated.
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•A novel modified weight concept included in algorithm MOPA is unique in nature.•New concept reduces inherent inaccuracy of weights significantly.•MOPA can handle subjective and ...objective attributes; benefit and cost criteria.•The algorithm MOPA fits itself in the class of applied MCDM techniques.•ANOVA and SA reveal MOPA as precisely accurate and effective decision making tool.
This investigation introduces multi objective performance analysis (MOPA), a novel multi-criteria decision making (MCDM) approach to solve decision problems in a supply chain. In this paper, an innovative modified weight concept is employed to modify the weights of the criteria in order to reduce the affect of the inherent inaccuracy involved with direct use of weights. Modified weight and normalized performance rating are integrated to compute modified weighted performance (MWP). Aggregate modified weighted performances (AMWP) of the alternatives are determined to evaluate benefit cost ratio (BCR) which is considered as the final selection index of the alternative. The proposed algorithm MOPA is illustrated with six real life decision problems in various stages of a supply chain to adjudge its enviable significance from the point of simplicity, feasibility and applicability. In order to ensure the compatibility, the result obtained by the proposed algorithm MOPA is compared with the proven and established MCDM methodologies TOPSIS, SAW, MOORA, ELECTRE II, and VIKOR. The comparative analysis shows that the achieved result perfectly matches with most of the cited decision problems of previous research works published in various journals. Analysis of variance (ANOVA) reveal that the modified weight concept reduces the relative dispersion of weights significantly, leads to precise decision. Sensitivity analysis (SA) and other investigations also find MOPA as a simple, robust, effective and precise decision making tool.
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•A novel MCGDM methodology based on group heterogeneity concept.•Group heterogeneity established from pair wise preference comparison matrix.•Biasness of information restricted by ...consistency check mechanism of AHP.•The algorithm fits itself in the class of established MCDM techniques.•Investigation finds the model as a robust and effective decision making tool.
Group decision making (GDM) is more effective in extracting the real case scenarios of the decision problems to add competitive advantages in a supply chain. Group members from wider spectrum of the environment naturally command variation in knowledge level to their respective domain. The degree of heterogeneity of the decision makers in a group plays a crucial role in realistic assessment of both alternatives and selection criteria. This paper proposes a new Multi criteria GDM approach in adroit exploitation of the group heterogeneity during evaluation process and restrict the biasness of information while decision making. The importance of the heterogeneous degree of expertise is established through pair wise preference comparison matrix. To overcome the biasness, the consistency check mechanism of analytical hierarchy process (AHP) is employed. A real case example on warehouse location selection in a supply chain is illustrated to demonstrate the validity and effectiveness of the proposed approach. In order to ensure the applicability, compatibility and validity of the proposed approach, comparative study is carried out with the proven and established MCDM methodologies SAW, MOORA, TOPSIS, VIKOR, ELECTRE II, COPRAS and PROMETHEE. ANOVA, Sensitivity analysis (SA) and other investigations find the proposed approach as a rational, robust, effective and precise decision making aid to the supply chain managers.
This paper deals with the testing of tensile and flexural behaviour of epoxy-reinforced natural fibre composites, for which Banyan fibres have been selected as the natural fibre. Variations are made ...in the orientation of the fibres to determine which orientation made the composite the strongest. The fibre strands are arranged in different orientations, such as the uniaxial, biaxial and criss-cross arrangements, to differentiate between the orientations and observe which arrangement exhibited the best mechanical behaviour. The fibres are initially washed with 0.5% weight/volume (w/v) NaOH solution, following which specimens of the composites are made using wooden moulds designed according to ASTM standards. Biaxial layers of E-glass are incorporated into the matrix in an attempt to enhance the mechanical properties of the specimen. The variances observed in the Young’s modulus are analysed to understand the factors that majorly impacted it. For a better understanding of the results, the chemical functional groups and the microstructure of the samples are analysed with the aid of Fourier-Transform Infrared Spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FESEM) and X-Ray powder Diffraction (XRD). Additionally, predictive models are simulated using Artificial and Deep Neural Networks to recognise patterns in the data, by varying specific parameters. The results obtained indicated that Banyan fibre composites can replace conventionally-used materials and serve real-world purposes better.
A large amount of wastewater is directly discharged into water bodies without treatment, causing surface water contamination. A rotating biological contactor (RBC) is an attached biological ...wastewater treatment process that offers a low energy footprint. However, its unstable removal efficiency makes it less popular. This study optimized operating parameters in RBC combined with external membrane filtration (RBC-ME), in which the latter acted as a post-treatment step to stabilize the biological performance. Response surface methodology (RSM) was employed to optimize the biological and filtration performance by exploiting three parameters, namely disk rotation, hydraulic retention time (HRT), and sludge retention time (SRT). Results show that the RBC-ME exhibited superior biological treatment capacity and higher effluent quality compared to stand-alone RBC. It attained 87.9 ± 3.2% of chemical oxygen demand, 45.2 ± 0.7% total nitrogen, 97.9 ± 0.1% turbidity, and 98.9 ± 1.1% ammonia removals. The RSM showed a good agreement between the model and the experimental data. The maximum permeability of 144.6 L/m
h bar could be achieved under the optimum parameters of 36.1 rpm disk rotation, 18 h HRT, and 14.9 d SRT. This work demonstrated the effective use of statistical modeling to enhance RBC-ME system performance to obtain a sustainable and energy-efficient condition.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
A large portion of water is consumed during various textile operations thereby discharging wastewaters with pollutants of huge environmental concern. The treatment of such wastewaters has promising ...impact in the field of environmental engineering. In this work, Fenton oxidation treatment was engaged to treat simulated textile wastewater. Box–Behnken design and response surface methodology were employed to optimize the efficiency of Fenton process. Iron dose, peroxide dose and pH were considered as input variables while the responses were taken as chemical oxygen demand and color removal. A total of 17 experiments were conducted and analyzed using second-order quadratic model. The quadratic models generated for chemical oxygen demand and color removal efficiencies were validated using analysis of variances, and it was found that the experimental data fitted the second-order model quite effectively. Analysis of variances demonstrated high values of coefficient of determination (
R
2
) for chemical oxygen demand and color removal efficiencies with values of 0.9904 and 0.9963 showing high conformation of predicted values to the experimental ones. Perturbation plots suggested that the iron dosage produced the maximum effect on both chemical oxygen demand and color removal efficiencies. The optimum parameters were determined as Fe
2+
dose—550 mg/L, H
2
O
2
dose—5538 mg/L, pH—3.3 with corresponding chemical oxygen demand and color removal efficiencies of 73.86 and 81.35%. Fenton process was found efficient in treatment of simulated textile wastewater, and optimization using response surface methodology was found satisfactory as well as relevant. From the present study, it can also be concluded that if this method is used as pretreatment integrated with biological treatment, it can lead to eco-friendly solution for treatment of textile wastewaters.
To investigate the leaching and recovery of heavy metals from low-grade automobile shredder residue (ASR), the effects of nitric acid (HNO3) and hydrogen peroxide (H2O2) concentrations, liquid/solid ...(L/S) ratio, leaching temperature and ASR particle size fractions on the heavy metal leaching rate were determined. The heavy metals were recovered by fractional precipitation and advanced Fenton process (AFP) at different pHs. The toxicity characteristic leaching procedure (TCLP) test was also performed in the residue remaining after heavy metal leaching to evaluate the potential toxicity of ASR. The heavy metal leaching efficiency was increased with increasing HNO3 and H2O2 concentrations, L/S ratio and temperature. The heavy metal leaching efficiencies were maximized in the lowest ASR size fraction at 303 K and L/S ratio of 100 mL/g. The kinetic study showed that the metal leaching was best represented by a second-order reaction model, with a value of R2 > 0.99 for all selected heavy metals. The determined activation energy (kJ/mol) was 21.61, 17.10, 12.15, 34.50, 13.07 and 11.45 for Zn, Fe, Ni, Pb, Cd and Cr, respectively. In the final residue, the concentrations of Cd, Cr and Pb were under their threshold limits in all ASR size fractions. Hydrometallurgical metal recovery was greatly increased by AFP up to 99.96% for Zn, 99.97% for Fe, 95.62% for Ni, 99.62% for Pb, 94.11% for Cd and 96.79% for Cr. AFP is highly recommended for the recovery of leached metals from solution even at low concentrations.
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•Nitric acid combined with H2O2 greatly increased the leaching of metals from ASR.•The leaching rate of metals increased with increasing temperature and L/S ratio.•The second-order kinetic model was best fitted (R2 ≥ 0.99) with the metal leaching.•The leaching rates of metals were controlled by both diffusion and chemical processes.•Application of the advanced Fenton process greatly increased the recovery of metals.
Over the last decade, carbon fibre-reinforced composites (CFRP) are increasingly used as lightweight material for various industrial applications. Due to the anisotropic material structure and its ...corresponding properties, novel design concepts and processing technologies were developed to further harness the material inherent lightweight potential. However, the material degradation in long-term use and failure behaviour is still considered a challenging issue for material scientists and engineers in particular. Therefore, concepts for structural health monitoring and their suitable implementation is still a major research topic. Among others, one solution uses the conductivity of carbon fibre yarns and their suitability to act as in-situ strain sensors. In the present work, the measurement principle bases on the usage of the piezo-resistive effect, meaning that every mechanical strain of the roving filaments causes a correlative change of the measurable electrical resistance. Since, these sensory elements need shielding from their surrounding carbon filaments of the composite structure, suitable fibre-based dielectric jackets have been developed with a wide range of suitable materials and textile processing technologies. In this contribution, the influence of the integrated carbon fibre sensors on the resulting mechanical performance of the composite structure is evaluated using an analysis of variances approach. Beyond that, the local composite morphology is analysed to evaluate the composite microstructure.
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