Ripening changes of Ras cheese made from recombined milk as affected by certain additives

An attempt has been made to accelerate the ripening of Ras cheese made from recombined milk (RM). RM cheese was made from curd with either a mixture of Fromase 100 (fungal rennet) and Kapalase L (an animal lipase) at concentrations of 0·025 and 0·05% or a slurry of fully ripened cheese at concentrations of 1 and 2%. These treatments enhanced flavour development, body characteristics, formation of soluble nitrogen compounds and free fatty acids. The proteinase/lipase mixture was the most effective. A rancid flavour and bitter taste were developed in 3–4-month-old RM cheese made with the higher concentration enzyme mixture.     

Monoglycerides: I. Synthesis by Direct Esterification of Fatty Acids and Glycerol

Direct reaction of fatty acid and glycerol was examined for the preparation of monoglycerides. Effects of different factors, namely, catalyst, time, temperature and reaction solvent on the yield of monoglycerides were investigated.     

Bayesian and non-Bayesian estimation for the pareto parameters using quasi-likelihood function

The quasi-likelihood function is used to derive Bayesian and non-Bayesian estimates for the unknown parameters of the Pareto distribution. In the Bayesian technique the likelihood function is replaced with the quasi-likelihood function when the mean-variance relationship is defined. The efficiency of the quasi-likelihood estimation relative to the maximum likelihood is calculated. Numerical illustrations for the Bayesian and quasi-Bayesian procedures are given.     

Buckling of prismatic structures under biaxial loading

This work presents an analysis and numerical results for the buckling of longitudinally stiffened prismatic structures that consist of an assemblage of flat plate and cylindrical panel components. The applied loading is assumed to induce uniform in-plane biaxial stresses, and all types of buckling modes (general, local, and coupled) are automatically accounted for in the analysis. Previous analyses of such problems by the exact (Wittrick) and approximate (Cheung) finite strip methods are based on the assumption that the structure is simply supported on the transverse ends by diaphragms (SS3 classical simple supports). The present work extends these analyses to include the case of completely clamped transverse ends (CC4), as well as simply supported ends. A one term Galerkin method is used to replace the governing partial differential equations of equilibrium for each component by ordinary differential equations in terms of the transverse coordinate, and the ordinary equations are solved exactly. The principle of virtual work is employed to obtain the stiffness matrix for each component. Numerial results are presented for a wide variety of CC4 and SS3 prismatic structures. These results compare favorably with available solutions.     

Multi-level image thresholding using Otsu and chaotic bat algorithm

Multi-level thresholding is a helpful tool for several image segmentation applications. Evaluating the optimal thresholds can be applied using a widely adopted extensive scheme called Otsu’s thresholding. In the current work, bi-level and multi-level threshold procedures are proposed based on their histogram using Otsu’s between-class variance and a novel chaotic bat algorithm (CBA). Maximization of between-class variance function in Otsu technique is used as the objective function to obtain the optimum thresholds for the considered grayscale images. The proposed procedure is applied on a standard test images set of sizes (512 × 512) and (481 × 321). Further, the proposed approach performance is compared with heuristic procedures, such as particle swarm optimization, bacterial foraging optimization, firefly algorithm and bat algorithm. The evaluation assessment between the proposed and existing algorithms is conceded using evaluation metrics, namely root-mean-square error, peak signal to noise ratio, structural similarity index, objective function, and CPU time/iteration number of the optimization-based search. The results established that the proposed CBA provided better outcome for maximum number cases compared to its alternatives. Therefore, it can be applied in complex image processing such as automatic target recognition.

     

Social group optimization for global optimization of multimodal functions and data clustering problems

Neural Computing and Applications - Cost and physical constraints in the engineering applied problems obligate finding the best results that global optimization algorithms cannot realize. For...     

Transient analysis of misaligned elastic tilting-pad journal bearing

For several reasons, almost all bearings operate in a misaligned condition, the present research work deals with analyzing the performance of a misaligned tilting-pad journal bearing under transient loading condition. The elastic and thermal distortions of the pad are considered and finite element analysis is used to calculate the pad’s elastic deformation. Using finite difference method, the Reynolds equation is simultaneously solved with the energy equation to calculate the pressure distribution and hence the other bearing performance characteristics. A modified fluid film thickness equation is used to take the effect of shaft misalignment and bearing elastic and thermal distortion into consideration.The results have shown that considering the thermo-elasto-hydrodynamic distortion improves the bearing performance in the case of misalignment shaft. And, at low values of shaft misalignment, the decrease in oil film thickness due to shaft misalignment is compensated by the increase in oil film thickness due to elastic and thermal distortions.     

Flexural and shear capacities of concrete beams reinforced with GFRP bars

This paper reports test results of 12 concrete beams reinforced with glass fibre-reinforced polymer (GFRP) bars subjected to a four point loading system. All test specimens had no transverse shear nor compression reinforcement and were classified into two groups according to the concrete compressive strength. The main parameters investigated in each group were the beam depth and amount of GFRP reinforcement. Two modes of failure were observed, namely flexural and shear. The flexural failure is mainly occurred due to tensile rupture of GFRP bars either within the mid-span region or under the applied point load. The shear failure is initiated by a major diagonal crack within the beam shear span. This diagonal crack extended horizontally at the level of the GFRP bars indicating bond failure.Simplified methods for estimating the flexural and shear capacities of beams tested are presented. The flexural capacity is estimated based on the compatibility of strains and equilibrium of forces. Comparisons between the flexural capacity obtained from the theoretical analysis and that experimentally measured in the current investigation and elsewhere show good agreement. To predict the shear capacity of the beams tested, four methods recently proposed in the literature for GFRP-reinforced concrete beams are used. These methods have been developed by modifying the ACI 318-99 shear capacity formula for steel-reinforced concrete beams to account for the difference in the axial stiffness of GFRP and steel bars. It has been shown that the theoretical predictions of the shear capacity obtained from these methods are inconsistent and further research needs to be carried out in order to establish a rational method for the shear capacity calculation of GFRP-reinforced concrete beams.     

Synthesis and Characterization of Some Poly(1,2-Phenylenedithiocarbamate)–Metal Complexes

Poly(1,2-phenylenedithiocarbamate) (PPDTC) was prepared by the reaction of 2-aminothiophenol with carbon disulfide followed by condensation through the removal of H₂S gas. PPDTC was used as a ligand to prepare four poly(1,2-phenylenedithiocarbamate)–metal complexes of iron(II), cobalt(II), copper(II), and lead(II), by refluxing with the metal salts. The polymer and its metal complexes were investigated by elemental analyses, UV–visible and IR spectroscopy, inherent viscosity, and magnetic susceptibility. The DC electrical conductivity variation with the temperature in the range 298–498 K of PPDTC and its polymeric copper complex was measured. Both polymer and polymer metal complexes showed an increase in electrical conductivity with an increase in temperature: typical semiconductor behavior. The proposed structure of the complexes is (MLX₂·mH₂O) _n .     

Characterization of the hard anodizing layers formed on 2014-T3 Al alloy,in sulphuric acid electrolyte containing sodium lignin sulphonate

The properties of hard anodizing layers formed on 2014 Al alloy in sulphuric acid electrolyte containing sodium lignin sulphonate were investigated. The corrosion behavior of 2014 Al alloy has been studied using potentiodynamic polarization technique. Anodic layers morphology and composition were examined by scanning electron microscope, energy dispersion X-ray (EDX), X-ray diffraction (XRD) and Fourier infrared spectroscopy (FTIR). The results showed that the corrosion resistance has been enhanced after hard anodizing of 2014 Al alloy. Addition of lignin sulphonate to the sulphuric acid electrolyte significantly improved the corrosion resistance of the anodized 2014 aluminum alloy by adsorption on copper-intermetallic phases. Adsorption of sodium lignin sulphonate on oxide surface has been confirmed by SEM, EDX, and FTIR. Phenolic and carboxylic groups in sodium lignin sulphonate are functional groups, which are responsible of complex formation on oxide surface. The morphology of the hard anodizing layer is non-homogenous due to the high copper content of 2014 Al alloy. Addition of sodium lignin sulphonate resulted in the formation of anodic layers with more homogeneity and fewer cracks.