Influence of analogical domains and comprehensiveness in explanation of analogy on the novelty of designs

The overall goal of this work is to support creativity of technical products by supporting improvement of novelty of designs at the conceptual stage. In this work, use of analogy as a means of aiding creativity was studied for its influence on novelty—a central aspect of creativity. To study their influence on novelty of designs, analogies were classified on the basis of two distinct but related parameters—‘distance between the source and the target domain’ and ‘level of comprehensiveness in explanation of analogues.’ ‘Distance between the source and the target domain’ is defined here as the conceptual closeness between these two domains, on the basis of which analogies are classified as biological domain, cross-domain or in-domain analogies. ‘Level of comprehensiveness in explanation of an analogy’ is defined here as the relative depth at which an analogue is explained, on the basis of which explanation of an analogue is classified as surface, shallow (both shallow and surface are less comprehensive) or deep (more comprehensive). Five design studies have been conducted in laboratory settings to study the influence of these parameters on novelty. The major findings from the study were the following: analogies from the biological domain produced significantly greater novelty in designs over analogies from cross- and in-domain for less comprehensive explanations; analogies from cross-domain and biological domains had no significant difference in novelty in designs for more comprehensive explanations.     

Practices, Perceptions and Avenues of Net-Based Promotions

Net as a medium is endowed with unique characteristics that has assisted the growth of e-commerce and in turn increased use of net-based sales promotions. The paper examines the practices, perceptions of net users and avenues of consumer sales promotions through this medium. To gain insight into current practices, consumer sales promotion on general, specialised and e-commerce sites were studied. An online survey of 161 net users was carried out to examine perceptions of net-based promotions over ten dimensions. The most frequently promoted product categories across sites were apparel, airlines, and books. Price-off followed by free gift offer was the most commonly used type of promotions. The results of various ANOVA tests revealed that perceptions did not vary across type of promotions but varied across product categories. Based on these findings managerial implications are discussed.     

Nanosized cellulose derivatives as green reinforcing agents at higher loadings in natural rubber

Cellulose nanoparticles (CelNPs) prepared by an acid hydrolysis process were acetylated under ambient conditions to retain the nanosize and to obtain hydrophobic nanosized derivatives. Green nanocomposites of natural rubber (NR) with more than 50 phr of cellulosic fillers were successfully developed by a commercial dry mixing process. The incorporation of cellulose acetate nanofiller up to 40 phr led to an almost linear increase in both the tensile and elongation properties, which were higher than even those of a composite with the conventional filler carbon black (CB). This was further supported by the almost uniform single‐phase morphology of the nanobiocomposite revealed by scanning electron microscopy and the high thermal stability. The results indicate the high degree of compatibility between the hydrophobic nanosized filler and the NR matrix. Although a drop in the mechanical strength was observed above 50 phr, the cellulose derivatives were expected to prove to be promising substitutes for the hazardous filler CB even at higher loadings. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40632.     

Stiffness properties of composite laminates with matrix cracking and interior delamination

Two modes of damage in composite laminates are considered: the intralaminar damage (matrix cracking) and the interlaminar damage (interior delamination). Using a vectorial representation of damage as internal variables in a phenomenological theory, relationships between the overall stiffness properties and the intensity of damage in the individual modes are determined. These relationships show that the intralaminar damage reduces all elastic moduli for a general orientation of the damage entities (cracks) and changes the initial orthotropic symmetry of a laminate. The interlaminar damage, however, does not change the symmetry but reduces the moduli. Predictions of the elastic moduli changes are compared with experimental results, showing excellent agreement.     

On fatigue life under stationary Gaussian random loads

Load parameters for a stationary Gaussian random load are taken as the location, scale and shape parameters of its power spectrum. The centre frequency of a power spectrum is proposed as a measure of fatigue life. A fatigue life function, formulated in terms of the load parameters, is evaluated from the test results obtained by fatigue testing a structural steel under six different power spectral shapes. The concept of a shape operator is employed to correlate fatigue lives under different power spectral shapes.     

Potential of Magnetic Resonance Spectroscopy in Assessing the Effect of Fatty Acids on Inflammatory Bowel Disease in an Animal Model

People with inflammatory bowel disease (IBD) are at risk for developing colorectal cancer, and this risk increases at a rate of 1% per year after 8–10 years of having the disease. Saturated and ω-6 polyunsaturated fatty acids (PUFAs) have been implicated in its causation. Conversely, ω-3 PUFAs may have the potential to confer therapeutic benefit. Since proton magnetic resonance spectroscopy (¹H MRS) combined with pattern recognition methods could be a valuable adjunct to histology, the objective of this study was to analyze the potential of ¹H MRS in assessing the effect of dietary fatty acids on colonic inflammation. Forty male Sprague-Dawley rats were administered one of the following dietary regimens for 2 weeks: low-fat corn oil (ω-6), high-fat corn oil (ω-6), high-fat flaxseed oil (ω-3) or high-fat beef tallow (saturated fatty acids). Half of the animals were fed 2% carrageenan to induce colonic inflammation similar to IBD. ¹H MRS and histology were performed on ex vivo colonic samples, and the ¹H MR spectra were analyzed using a statistical classification strategy (SCS). The histological and/or MRS studies revealed that different dietary fatty acids modulate colonic inflammation differently, with high-fat corn oil being the most inflammatory and high-fat flaxseed oil the least inflammatory. ¹H MRS is capable of identifying the biochemical changes in the colonic tissue as a result of inflammation, and when combined with SCS, this technique accurately differentiated the inflamed colonic mucosa based on the severity of the inflammation. This indicates that MRS could serve as a valuable adjunct to histology in accurately assessing colonic inflammation. Our data also suggest that both the type and the amount of fatty acids in the diet are critical in modulating IBD.     

Self-assembly and alignment of semiconductor nanoparticles on cellulose nanocrystals

The synthesis of cadmium sulfide (CdS), zinc sulfide (ZnS), and lead sulfide (PbS) nanoparticle chains on cellulose nanocrystal (CNC) templates can be accomplished by the reaction of the precursor salts. The use of a cationic surfactant, cetyltrimethylammonium bromide (CTAB), was critical for the synthesis of well-defined semiconductor nanoparticle chains on the surface of the CNCs. The semiconductor nanoparticle particle size and packing density on CNC surface could be controlled by the variation of the precursor concentration and the pH of the salt solution.     

A comparative study on the magnetic properties of MFe12O19 and MAlFe11O19 (M = Sr, Ba and Pb) hexaferrites with different morphologies

M-type nano hexaferrites MFe₁₂O₁₉ and MAlFe₁₁O₁₉ (M = Sr, Ba and Pb) have been prepared by the sol-gel method to investigate the shielding effect of inorganic ions KCl, KBr and KI on the phase growth of ferrites. FTIR frequency bands in the range 560-580 cm⁻¹ and 430-470 cm⁻¹corresponds to the formation of tetrahedral and octahedral clusters of metal oxides in ferrites, respectively. X-ray powder diffractographs do not show any peaks for the as obtained samples showing the amorphous nature of the samples, however regular peaks for M-type structure have been obtained for all the annealed samples. There is negligible small change in the lattice parameters ‘a’ and ‘c’ with substitution of the hexagonal ferrites with aluminium. Magnetic measurements showed that the coercivity (Hc) values of all the samples with KCl and KBr enhance due to KCl and KBr to act as deactivators. However, the coercivity value decreases with KI as it oxidise to I₂ during annealing. The saturation magnetization of the hexaferrites decreases with Al³⁺ ion substitution for Fe³⁺ ion due to preferential occupancy of aluminium in octahedral sites.     

Facile reduction of nitrophenols: Comparative catalytic efficiency of MFe2O4 (M = Ni,Cu, Zn) nano ferrites

Nano ferrites of the formula MFe₂O₄ (M = Ni, Cu, Zn), synthesized using sol–gel technique, were employed to catalyze the reductive transformation of nitrophenols to aminophenols. The catalytic reduction was carried out in the excess of NaBH₄ as reducing agent in aqueous medium at room temperature. CuFe₂O₄ and NiFe₂O₄ were found to be active for the reduction of nitrophenols with significant difference in their activities whereas ZnFe₂O₄ was found to be inactive. The kinetics of the reduction of nitrophenols to aminophenols was also investigated. The reaction followed pseudo first order kinetics. The first order rate constant values for 30 mol% of CuFe₂O₄ and NiFe₂O₄ for the reduction of 2-nitrophenol were observed to be 3.68 min⁻¹ and 0.33 min⁻¹ respectively. The rates of reduction for the three isomers of nitrophenol were also studied and were observed to follow the order – 2-nitrophenol > 4-nitrophenol > 3-nitrophenol. The selective formation of aminophenol was confirmed using LC-MS, ¹H NMR and FT-IR spectroscopic techniques.     

Tunable morphology and resistivity of ternary polymer composites of carbon black/low density polyethylene/ethylene-vinyl acetate with carbon blacks having different surface properties

Medium to extra-high voltage electrical cables typically comprise a semiconductive polymer composite layer to homogenize the electromagnetic field through the cables. The semiconductive layers usually contain a high content of carbon black (CB) for reduced electrical resistivity. In this study, we found that both the morphology and resistivity of a ternary polymer composite of CB/low density polyethylene (LDPE)/ethylene-vinyl acetate (EVA) depend on CBs used and the order of addition. Three types of CB were investigated. CB-A, which has the lowest surface energy and the most uniform surface energy profile, exhibits a strong affinity to LDPE and always segregates in the LDPE phase whether it is first added in the LDPE phase or the EVA phase. CB-B and CB-C, which have higher and less homogeneous surface energies, distribute differently with different orders of addition. We observe a significant reduction in the percolation threshold of CB-A in the CB/LDPE/EVA composite, but not with CB-B or CB-C. Adding CB-A in the LDPE phase first results in substantially lower resistivity than adding it in the EVA phase first, whereas adding CB-B or CB-C in the LDPE phase first results in higher resistivity than adding them in the EVA phase first.