On some measures for grouping efficiency

One of the traditional methods on managing risk is taken using engineering decisions taken during the project development. In this paper, we propose a new method for risk assessment of a tunnel project where there are three main parameters called taskmaster, adviser, and contractor. The proposed model of this paper is built based on interactive framework of a game theory where, in making decision, each player considers other possible risks choices. We implement three-person cooperative game theory combined with an interactive decision structural model of fuzzy analytical hierarchy process to perform a balance between actions and suitable cooperative strategy for each player. The results reveal that collaboration strategies give the highest outcome for the three players. It also recommends owner managers, design managers, and contractor managers to make collaboration in undertaking innovation while the operator managers need to let an independent organization clearly identify the appropriate risk mitigation measures to be implemented in a timely manner.     

Electrokinetic dewatering of Turkish glass sand plant tailings

In this study, the dewatering of glass sand plant tailings from Mersin, Turkey was investigated using an electrokinetic technique. The particle size (d(80)) of the solid waste material tested was less than 0.020 mm and consisted mainly of silica, orthoclase, alumina, potassium and iron oxides. In current plant practice, Larox high-pressure filters are used to produce a filter cake containing 22-25% moisture. As an alternative, a laboratory-scale dewatering pond using an electrokinetic technique was designed and a final product (cake) containing 34% moisture was obtained after 24h treatment using 14.6 V direct current applied for 40 min. When the treatment continued up to 48 h, a firm-to-hard cake was produced.     

Synthesis and characterization of acrylic rubber/silica hybrid composites prepared by sol‐gel technique

The organic–inorganic hybrid composites comprising acrylic rubber and silica were synthesized through sol–gel technique at ambient temperature. The composites were generated through the acid‐catalyzed hydrolysis and subsequent condensations of inorganic tetraethoxysilane (TEOS) in the organic acrylic rubber (ACM), solvated in tetrahydrofuran. The morphology of the hybrid materials was investigated by using the transmission electron microscope (TEM) and scanning electron microscope (SEM). Transmission electron micrographs revealed that the silica particles, uniformly distributed over the rubber matrix, are of nanometer scale (20–90 nm). The scanning electron micrographs demonstrated the existence of silica frameworks dispersed in the rubber matrix of the hybrid composites. The X‐ray silicon mapping also supported that observation. There was no evidence of chemical interaction between the rubber phase and the dispersed inorganic phase, as confirmed from the infrared spectroscopic analysis and solubility measurements. Dynamic mechanical analysis indicated mechanical reinforcements within the hybrid composites. The composites containing in situ silica, formed by sol–gel technique, demonstrated superior tensile strengths and tensile modulus values at 300% elongations with increasing proportions of tetraethoxysilane. However, the improvements in physical properties with similar proportions of precipitated silica were not significant. Maximum tensile strength and tensile modulus were obtained when the rubber phase in the hybrid composites was cured with ammonium benzoate and hexamethylenediamine carbamate system, as compared with benzoyl peroxide cured system. Thermal stability of the hybrid composites was not improved appreciably with respect to the virgin rubber specimen. Residue analysis from thermogravimetric study together with infrared spectroscopic analysis indicated the presence of unhydrolyzed tetraethoxysilane in the hybrid composites. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2579–2589, 2004     

Evidence of photoluminescence quenching in poly(3-hexylthiophene-2,5-diyl) due to injected charge carriers

Photoluminescence spectra of poly(3-hexylthiophene-2,5-diyl) (P3HT) has been studied in forward and reverse bias direction in an indium tin oxide (ITO)/P3HT/Al Schottky device. It has been observed that photoluminescence quenching is relatively higher in forward direction and the quenching pattern gets reversed when a thin insulating layer of poly(4-vinylphenol) is coated on ITO. The observed behavior of photoluminescence quenching pattern has been explained on the basis of interaction of the injected charge carriers with the excitons generated in the bulk of P3HT together with the interaction of excitons with the applied electric field.     

Tribological performance of hydrophilic diamond-like carbon coatings on Ti–6Al–4V in biological environment

Tribological performance of diamond-like carbon (DLC) and Si doped DLC (Si-DLC) films on Ti–6Al–4V under bovine serum as well as water and ambient air condition has been studied in terms of surface modification with O₂ plasma treatment for superhydrophilic surface. A tribo-test revealed that bovine serum significantly enhanced the tribological performance on all DLC surfaces in comparison with those under water or in air medium. Especially, O₂ plasma treated Si-DLC coatings with superhydrophilic nature were found to lower the wear and increase coating stability associated with macromolecules especially proteins in the bovine serum and their interactions with surfaces.     

Sensitivity to the proportions of faces that vary in human likeness

Despite the often quoted adage “beauty is in the eye of the beholder,” studies indicate people perceive certain facial and bodily proportions as attractive regardless of their culture. This preference, which is present even in infants, may be more hardwired than learned. Designers of computer games, animation, virtual reality, and robots must make choices about how to depict humanlike forms. An understanding of human perception and preferences can lead to design principles for successful interaction. This study measured human responses to varying facial proportions in people, androids, mechanical-looking robots, and two- and three-dimensional characters. Participants showed greater agreement on the best proportions of faces they considered more humanlike and more attractive and less tolerance for deviation from these proportions in more attractive faces.     

Hypocholesterimic effects of cold and hot extracted virgin coconut oil (VCO) in comparison to commercial coconut oil: Evidence from a male wistar albino rat model

The hypolipidemic effect of cold extracted virgin coconut oil (CEVCO) and hot extracted virgin coconut oil (HEVCO) compared to commercially available coconut oil (CCO) was studied using male wistar rats. Groups were designated as control, hypercholesterimic control (HC Control), HC+10% (CEVCO), HC+15% (CEVCO), HC+10% (HEVCO), HC+15% (HEVCO) and HC+15% (CCO). Control rats were fed a basal diet while other groups were initially fed a hypercholesterimic diet (2% cholesterol and 0.25% bile salts) for 15 days, then fed with CEVCO or HEVCO (both at 10% and 15% levels), and commercial coconut oil (15%) for 30 days. Total cholesterol and LDL cholesterol levels were significantly (p<0.05) decreased by approximately 25 and 40%, respectively, in the blood plasma, while HDL cholesterol increased significantly (p<0.05) by approximately 21% in HEVCO fed rats. Tissue cholesterol and triacylycerol (TAG) levels in both liver and heart tissues decreased significantly (p<0.05) in CEVCO and HEVCO fed animals, compared with CCO fed rats.     

Discrepancy between TPD- and FTIR-based measurements of Brønsted and Lewis acidity for sulfated zirconia

Temperature-programmed desorptions (TPD) of isopropylamine (IPA), NH₃, and pyridine were compared with diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) of pyridine to determine the effect of H₂O on the Brønsted and Lewis acidities of two sulfated zirconia (SZ) catalysts. Although the traditional interpretation of pyridine infrared spectra showed an apparent increase in Brønsted acidity upon treating SZ with H₂O, TPD spectra showed that H₂O displaced IPA from approximately one-fifth of the Lewis sites with no corresponding increase in Bronsted acidity. Water treatment prior to TPD displaced similar amounts of both NH₃ and pyridine. The primary effect of H₂O is displacement of weakly adsorbed basic probe molecules from Lewis sites, rather than the conversion of Lewis sites to Brønsted sites. Finally, different types of analyses (e.g. infrared or TPD) of catalyst acidity yield dramatically different conclusions regarding Brønsted and Lewis acidity.