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The present study describes a method to fabricate polymer matrix nanocomposites by reinforcing multi-walled carbon nanotubes through an extrusion process. Linear low density polyethylene (LLDPE) powder and multi-walled carbon nanotubes (CNTs) are first dry mixed and extruded in the form of filaments by a single screw extrusion process. After extrusion, the filament is partially cooled by chilled air, dried, and continuously wound in a spool. The filaments are then laid in roving, stacked in a unidirectional fashion, and consolidated in a compression molding machine to come up with laminated composites. Thermo gravimetric analysis (TGA) has been performed to compare the thermal stability of as-fabricated composites with the neat polymer. The TGA result shows that the extruded composites are thermally more stable than their neat counterparts. The crystalline nature of CNTs and of as-fabricated composites were identified by X-ray diffraction (XRD) studies. The XRD results indicate that the nanocomposite materials are more crystalline than the neat systems, and the differential scanning calorimetry studies also confirmed the same trend. The scanning electron microscopy result showed that the sizes of extruded neat and nanophased filaments were about 117 and 73 μm, respectively. Tensile coupons from the consolidated panels were then extracted both in longitudinal (0°) and in transverse (90°) directions and tested in a Minimat Tester. It was found that with the addition of 2% by weight of CNTs in LLDPE, the tensile strength and modulus of the composite has increased by about 34 and 38%, respectively. The (0°) and (90°) coupons have also demonstrated that there are directional effects in the tensile response, which is believed to have been caused by the alignment of CNTs during the extrusion process. It is our understanding that such improvement in properties is because of the increase in crystallinity of the polymer due to CNT infusion, and also due to the alignment of CNTs in the extrusion direction in the nanocomposites. Details of the fabrication procedures, synthesis of composites, and mechanical testing are included in the paper.

An analytical solution for consolidation around spherical cavity contraction is developed. This solution has the potential to evaluate consolidation around tunnel heads. The initial excess pore water pressure immediately after the creation of the cavity is estimated from the cavity expansion/contraction theory using a linear-elastic-perfectly-plastic soil model. Expressions for the decay of pore water pressure with time are obtained using elasticity. Curves showing the variation of pore water pressure with time are plotted in nondimensional form. Comparison with two-dimensional coupled stress-pore pressure finite element analysis shows that the proposed semi-analytical solution can successfully predict the poro-elasto-plastic behavior around spherical cavity.

The behavior of pile composite foundation is studied using the flexibility method. During the analysis, determination of the flexibility matrix (settlement) is critical. However, conventional methods of Winkler and elastic half-space foundation models are incapable of considering the time effects of soil consolidation and creep. The foundation model of Zaretsky and Tsytovich [1965] can be used to evaluate settlement for unsaturated soils, but the complexity of numerical integration over an arbitrary loading area hinders its application. In this paper, a novel scheme is proposed for numerical integration by rotating the loading surface using the equiareal transformation technique. Therefore, a simplified closed-form solution is developed to calculate time dependent settlement for foundation soils. The efficacy of the proposed technique is demonstrated using illustrative examples of an elastic half-space, a rigid raft foundation without piles, and rigid pile composite foundations with multiple piles under surface loading. Furthermore, parametric study is conducted to evaluate the sensitivity of model parameters. The permeability $k$ and Poisson’s ratio $\nu$ are found to be important, whereas pore pressure coefficient $\beta$ and degree of saturation $B$ are less significant in the calculation.

In this study, we find savings deposits have contributed significantly to the effectiveness of regulation induced consolidation within the banking sector in so far as improvements in banking system structure, output, profitability and competitiveness are concerned. Specifically, we find savings deposits are key parameters in the transition from a banking structure within which profitability is primarily determined by liquidity during the pre-consolidation period (2007–2008) to a banking structure within which profitability is primarily a function of loan portfolio growth (output) during the post-consolidation period (2010–2012). In spite of the increase in importance of savings deposits for banking system competition, output, or profitability during the post-consolidation period, savings deposit rates have decreased by about 50% between the pre- and post-consolidation periods. Interest rates on savings deposits also do not lie on the efficiency frontier for loan production. Combined, our findings indicate the benefits of consolidation that accrue from savings deposits have yet to translate into social welfare benefits for banks' retail customers.

The European Union (EU) is a heterogeneous political and economic structure comprising 28 nations, differing in terms of size, population, economic development and institutional efficiency. National socio-economic context determines countries’ growth potential and their ability to compete for foreign markets. The socio-economic discrepancies present, respectively, between the Western, Northern, Southern and Eastern EU nations still persist, thus reducing the community’s ability to compete on the global market, especially with the USA, Japan and China, which are considered the main powerhouses of the world’s economy capable of challenging economic positions of the European Union. Consequently, the present research aims to assess to which extent economic growth determinants in the European Union differ taking into account the regional context. An individual per region regression analysis was developed intending to identify which are the determinants of economic development at the level of EU’s geographical regions. The results reached confirm this assumption underlining the fact that there are significant dissimilarities between the motivators of economic progress in the EU. This fact should particularly concern the European elites as these variations determine the further accentuation of development disparities not only among the countries but also between entire groups of states.

We examine whether SFAS 166/167, which ended exclusion of qualifying special purpose entities (QSPEs) from consolidation, impacted the cost of equity capital for a sample of banks. This exclusion previously allowed banks to avoid consolidating many, risky asset securitization transactions. These transactions were prevalent during and after the global financial crisis (GFC). We compare changes in the cost of equity capital for a sample of banks that consolidated SPEs after implementation of SFAS 166/167, to a control group of banks that reported no material impact of SFAS 166/167. We find the cost of equity capital increased significantly more for the banks consolidating previously unconsolidated SPE’s, than for the banks that were relatively unaffected by the rule change. In particular, we find that banks with greater reductions to their reported Tier-1 capital ratios as a result of consolidation are associated with significantly greater cost of equity capital in the post-SFAS166/167 period.

This study examines whether, and to what extent, SFAS166/167 changed the role of securitization in bank liquidity and lending activities. We compare the sensitivity of on-balance sheet loan growth to the loan portfolio liquidity index proposed by Loutskina [(2011) The role of securitization in bank liquidity and funding management, Journal of Financial Economics 100, 663–684] between affected banks and control banks. We find that SFAS166/167 is significantly associated with a reduction in the use of securitization to enhance on-balance sheet liquidity, consistent with the view that consolidation on balance sheets may render the securitization of loans too costly to be considered an effective source of liquidity. In addition, we find that affected banks with the highest increase in liabilities from consolidating Qualified Special Purpose Entities (QSPEs) experienced a significant decrease in lending activities relative to the control banks. This is likely because consolidating former QSPEs may adversely affect the ability and willingness of banks to engage in securitization and issue new loans. Taken together, our results suggest that SFAS166/167, requiring the consolidation of former QSPEs, led to a decline in the role of securitization as a liquidity management tool in banks and to a significant decline in lending.

In this paper, a theoretical study is made of the consolidation of a composite foundation reinforced by piles in double-layered soil. A more reasonable initial condition for this kind of problem is derived from the equilibrium equation and the equal strain assumption. Then, the general analytical solution for excess pore pressure within the surrounding soil is obtained under the influence of several important factors. The general expressions for the whole average degree of consolidation of a composite foundation, both in terms of stress and deformation, are then proposed. With above theory, the special solutions for two particular cases, which consider constant loading and ramp loading, are given in detailed forms. Finally, a parametric study is made. The results show that the reduction in permeability and modulus of layer two, area replacement ratio and modulus of the pile reduce the consolidation rate of a composite foundation. However, the reduction in construction time accelerates the consolidation.

We introduce a mathematical model to improve our understanding of consolidation processes and to take into account the fine scale evolution of reaction pathways. We focus on a silicone called TEOS (Tetraethyl Orthosilicate). The model is based on differential equations, inspired by the theory of porous media, which describes the process of consolidation in terms of filtration and solidification. Our main goal is the prediction of the ultimate depth of filtration of TEOS, according to the environmental and material data. The model has been calibrated on laboratory tests with a very good agreement with experimental data.

This chapter focuses on the role of travel agencies and tour operators in the tourism system and their ability to adapt to constant changes in an increasingly dynamic tourism market. Special emphasis is given to the impact of information technology. The economic objectives of these entities are explained, as are the consequences of the consolidation processes that have helped to create a leisure travel value chain which provides customers with a complex service from a single source. All of these factors have brought significant changes to the structure of the tourism industry.

Processing of information into long-term storage (consolidation of memory) and the retrieval of processed knowledge is not independent of the physiological state of animal and man. The neuroendocrine system which is composed of central nervous and peripheral components i.e., peptidergic neurons and forming of membrane-active steroids in the brain, on the one hand, and releasing hormones into the circulation, on the other hand, is the primary messenger of bodily states. The neuroendocrine system is a rapidly responding one to environmental changes and, in turn, assures optimal conditions for processing information into long-term storage. Retrieval of knowledge is then affected either by pro-active influence of neuroendocrine principles during learning and consolidation or by a simple presence (tonic actions) during retrieval. These general conclusions can be drawn from studies devoted to the mnemonic effects of circulating adreno-sympathetic catecholamines epinephrine and norepinephrine, adrenal corticosteroids and (neuro) peptide vasopressin. The action of these hormones is of central nervous nature via direct or indirect mechanisms involving the central nucleus of the amygdala and the hippocampus as major targets.

The most labile and most sensitive link in the chain of events that constitute the memory process is the phase of consolidation that follows after acquisition, by which memories are transformed, at a loss, from an unstable into a stable state. Therefore the pharmacology of consolidation has been better studied than that of the other phases of memory (acquisition, storage, retrieval). Pharmacological studies unveiled much information concerning the actual mechanism of consolidation. This involves excitatory glutamatergic and cholinergic muscarinic synapses in the amygdala, medial septum and hippocampus, inhibited by benziodiazepine-regulated GABA-A synapses and modulated by B-noradrenergic terminals. Other additional neutrotransmitter systems, possibly different in each structure, may also intervene. Peripheral hormones reflexly modulate these mechanisms. The amygdala, medial septum and hippocampus process different aspects or components of memories (spatial, aversive, etc.). The entorhinal cortex, which receives projections from these three structures, has a post-consolidational, presumably integrative function. The glutamatergic synapses involved in memory consolidation in the amygdala and hippocampus sustain this late role of the entorhinal cortex through the generation of relatively brief long-term potentiations.