A thermodynamic framework to develop rate-type models for fluids without instantaneous elasticity

In this paper, we apply the thermodynamic framework recently put into place by Rajagopal and co-workers, to develop rate-type models for viscoelastic fluids which do not possess instantaneous elasticity. To illustrate the capabilities of such models we make a specific choice for the specific Helmholtz potential and the rate of dissipation and consider the creep and stress relaxation response associated with the model. Given specific forms for the Helmholtz potential and the rate of dissipation, the rate of dissipation is maximized with the constraint that the difference between the stress power and the rate of change of Helmholtz potential is equal to the rate of dissipation and any other constraint that may be applicable such as incompressibility. We show that the model that is developed exhibits fluid-like characteristics and is incapable of instantaneous elastic response. It also includes Maxwell-like and Kelvin-Voigt-like viscoelastic materials (when certain material moduli take special values).Comment: 18 pages, 5 figure

Multiple template matching using the expansion filter

The paper describes a multiple-template generalization of a newly developed approach for template matching by signal expansion into a set of non-orthogonal template-similar basis functions. The single-template method is proven to be equivalent to "restoration" of undegraded images using the Wiener filter and optimizes a new and more practically defined matching quality criterion that the authors call discriminative signal-to-noise ratio (DSNR). Compared to the widely used matched filtering approach (also known as correlation matching) which is based an projection, expansion matching is based on decomposition and is shown to be more robust in conditions of noise, superposition and severe occlusion. In the paper, the authors extend the DSNR optimization approach to include more than one template. The generalized expansion filter presented is optimal in terms of DSNR and can be designed to elicit any desired response for each of the templates, while optimizing the DSNR criterion. The approach considers additive noise as a parameter and leads to a general formulation, of which many previous approaches (such as the synthetic discriminant function) form special cases. In the case of a single template, the formulation reverts to the previously mentioned Wiener restoration filter

Effects of Velocity-slip and Viscosity Variation for Lubrication of Roller Bearings

A generalised form of Reynolds equation for two symmetrical surfaces is derived considering velocity-slip at the bearing surfaces. This equation is applied to study the effects ofvelocity -slip for the lubrication of roller bearings under lightly loaded conditions. Expressions for the point of cavitation, load capacities, and coefficient of friction obtained are also studied theoretically for various parameters

Synthesis, characterization, antibacterial, antifungal and anthelmintic activities of a new 5-​nitroisatin Schiff base and its metal complexes

The copper (II)​, cobalt (II)​, nickel (II) and zinc (II) complexes of 5 - nitroisatin Schiff base (L) (L = Schiff base derived from 5-​nitroisatin and 2-​methyl-​4-​nitroaniline) were synthesized and characterized. The authenticity of the ligand and its metal complexes has been established by micro anal., IR, NMR, LC​/MS, UV-​VIS and elec. conductance measurements. The ligand acts as a bidentate agent in which the carbonyl oxygen and the azomethine nitrogen of 5-​nitroisatin are involved in co-​ordination. Square planar geometry was proposed for the Cu (II) and Ni (II) complexes and tetrahedral geometry was proposed for the Co (II) and Zn (II) complexes. The ligand and its metal complexes have been screened for antibacterial activity against Staphylococcus aureus, Escherichia coli, etc. and for antifungal activity against Aspergillus niger, Aspergillus flavous, etc. The Schiff base and its complexes were also screened for anthelmintic activity on earthworms. Both samples displayed significant activitie

Acute toxicity of metasystox to wedge clam, Donax cuneatus from west coast

96h acute toxicity tests were performed using commercial grade metasystox on the marine wedge clam, Donax cuneatus during summer 1985. The behaviour and mortality rates were recorded periodically. Most of the dams responded in opening the shell valves and extending the siphons quicker in low test concentrations (0.004-0.0052 p.p.m) but this was slow and late in high concentrations (0.0056-0.008 p.p.m). Mortality began to occur in 0.008 p.p.m. from 12 h, whereas, in 0.0052 p.p.m. from 60 h onwards. The observed LC sub(0) value was 0.004 p.p.m. and LC sub(50) 0.0064 p.p.m. The regression equation established was Y = 79.0891 + 33.4523 X. The rate of oxygen concentration increased at LC sub(0) and LC sub(50) values compared to control indicating the disturbed physiological adjustment. The results are correlated with physico-chemical parameters of seawater and discussed in the light of pesticide toxicity to the dam

Automatic Raaga Identification System For Carnatic Music Using Hidden Markov Model

As for as the Human Computer Interactions (HCI) is concerned, there is broad range of applications in the area of research in respective of Automatic Melakarta Raaga Identification in music. The pattern of identification is the main object for which, the basic mathematical tool is utilized. On verification, it is observed that no model is proved consistently and effectively to be predicted in its classification. This paper is, therefore, introduces a procedure for Raaga Identification with the help of Hidden Markov Models (HMM) which is rather an appropriate approach in identifying Melakarta Raagas. This proposed approach is based on the standard speech recognition technology by using Hidden continuous Markov Model. Data is collected from the existing data base for training and testing of the method with due design process relating to Melakarta Raagas. Similarly, to solve the problem of automatic identification of raagas, a suitable approach from the existing database is presented. The system, particularly, this model is based on a Hidden Markov Model enhanced with Pakad string matching algorithm. The entire system is built on top of an automatic note transcriptor. At the end, detailed elucidations of the experiments are given. It clearly indicates the effectiveness and applicability of this method with its intrinsic value and significance

Synthesis And Characterization Of Co-Doped SnO2/TiO2 Semiconductor Nano Crystallites Via Sol-Gel Method

SnO2/TiO2 nano particles are novel wide band gap semiconductors with modified applications of SnO2 and TiO2 in some fields including gas sensing, photo catalytic, solar cells and so on. The Co-doped SnO2/TiO2 nano particles were obtained via sol-gel method with different amounts of doping material as 2.5 %, 6 % and 10 mol %. The crystallite sizes of resulting material were from 3.8 nm for 0.1 wt % Co-doped SnO2/TiO2 to 19.1 nm for un-doped. Morphology and nanostructure of the crystalline SnO2/TiO2 nano particles were characterized by means of X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), Thermal gravimetric analysis (TGA), field emission scanning electron microscopy (FESEM) and energy dispersive X-ray spectroscopy (EDX). It has been shown that fine semiconductor nano structures were formed. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/933