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Nanofluids have analysis of wide applications of energy technologies in recent times as the thermal amplification of several manufacturing industries. A mathematical model is developed to stimulate electrokinetic transfer through peristaltic pumping of couple-stress micropolar nanofluids in a microchannel. The effects of Joule heating and chemical reaction have been considered. The remarkable properties of nanofluid are demonstrated by thermophoresis and Brownian motion characteristics. Thermophoresis has relevance in mass transport processes in many higher temperature gradient operating systems. The highly non-linear partial differential equations into ordinary differential equations by using appropriate similarities transformations. The graphical estimates are presented for the axial velocity, spin velocity, temperature of nano fluid, concentration and pumping characteristics. The outcomes of this study reveal the activation of Joule heating and chemical reaction effects in electroosmosis peristaltic transport of couple-stress, micropolar and nanofluids. This model is applicable to the study of chemical fraternization/separation procedures and bio microfluidics devices for the resolution of diagnosis.

In this study, soils from two locations namely Rudrapur and Khatima from Uttarakhand, India adjacent to Himalayan Frontal Thrust (HFT) have been considered for response analysis. The in-situ and dy...

Experimental investigations on soil samples collected from the sites of Baraut, Noida and Mandi in North India have been performed to study the static and cyclic behavior of soil. Liquefaction potential of the sites near Himalayan range is also carried out. The SPT and downhole seismic tests have been performed for the estimation of static and dynamic properties of soil. Strain-controlled cyclic triaxial tests are also carried out on soil samples collected from the borehole at various depths up to 30 m for the evaluation of dynamic soil properties. The study examined the effects of parameters such as cyclic shear strain, loading frequency and overburden pressure on the cyclic behavior of the soil. One- and two-dimensional dynamic response analysis has been performed on three sites. The initiation of initial liquefaction ranged from 202 to 752 cycles for the Baraut site, 212 to 722 cycles for the Noida site, and 121 to 617 cycles for the Mandi sites. The final design response spectra of the sites are obtained from 1D ground response analysis. The results from the response analysis have been compared with the reported results. The soils from the present study areas are prone to liquefaction at 10 m to 15 m from the ground surface.

Generally structures are subjected to different types of loadings throughout their life time. These loads can be either discrete in nature or continuous in nature and also these can be either stationary or non stationary processes. This means that the structural reliability analysis not only considers random variables but also considers random variables which are functions of time, referred to as stochastic processes. A stochastic process can be viewed as a family of random variables. When a structure is subjected to a random loading, based on the stresses developed in the structure and failure criteria the failure probability can be estimated. In practice the structures are designed with higher factor of safety to take care of such random loads. In such cases the structure will fail only when the random loads are cyclic in nature. In traditional reliability analysis, the variation in the load is treated as a random variable and to account for the number of occurrences of the loading the concept of extreme value theory is used. But with this method one is neglecting the damage accumulation that will take place from one loading to another loading. Hence, in this paper, a new way of dealing with these types of problems has been discussed by using the concept of stochastic fatigue loading. The random loading has been considered as earthquake loading. The methodology has been demonstrated with a case study on nuclear power plant piping.

Any earthquake event is associated with a rupture mechanism at the source, propagation of seismic waves through underlying rock and finally these waves travel through the soil layers to the particular site of interest. The bedrock motion is significantly modified at the ground surface due to the presence of local soil layers above the bedrock beneath the site of interest. The estimation of the amplifications in ground response due to the local soil sites is a complex problem to the designers and the problem is more important for mega cities like Mumbai in India, where huge population may get affected due to devastations of earthquake. In the present study, the effect of local soil sites in modifying ground response is studied by performing one dimensional equivalent-linear ground response analysis for some of the typical Mumbai soil sites. Field borelog data of some typical sites in Mumbai city viz. Mangalwadi site, Walkeswar site, BJ Marg near Pandhari Chawl site are considered in this study. The ground responses are observed for range of input motions and the results are presented in terms of surface acceleration time history, ratio of shear stress to vertical effective stress versus time, acceleration response spectrum, Fourier amplitude ratio versus frequency etc. The typical amplifications of ground accelerations considering four strong ground motions with wide variation of low to high MHA, frequency contents and durations are obtained. Results show that MHA, bracketed duration, frequency content have significant effects on the amplification of seismic accelerations for typical 2001 Bhuj motion. The peak ground acceleration amplification factors are found to be about 2.50 for Mangalwadi site, 2.60 for Walkeswar site and 3.45 for BJ Marg site using 2001 Bhuj input motion. The response spectrum along various soil layers are obtained which will be useful for designers for earthquake resistant design of geotechnical structures in Mumbai for similar sites in the absence of site specific data.

The traditional reliability analyses, considers components to be in binary state, either functional or faulty, and does not consider the concept of multi state or intermediate states between these two binary states. However, there are several components, which need to be operated in different states and their failure criterion also depend on these states. Hence, when dealing with these types of components one should use multi state concept. This can be achieved by modeling the components with mechanistic models, which can give a new dimension for reliability analysis for multiple states. The mechanistic model approach is based on the first principles of science and engineering which provides details about the various failure mechanisms and thereby improved understanding of the associated root causes of the failure and driving forces responsible for component failures. In this paper a general methodology for modeling the components with mechanistic models has been explained and is further illustrated with an example component. A case study on feed water system (consisting of control valves and other mechanical components) of a typical nuclear reactor has been presented. (C) 2011 Elsevier Ltd. All rights reserved.

A rare case of Myxoma of right maxilla in a 25 year female, presenting as-bilateral nasal obstruction with destruction of the septum and maxillary antral bone is reported.

Joshi effect (±δi) an almost instantaneous and reversible photo-variation of the discharge current (i), is studied in various types of discharge vessels, charged with air, H2 and I2 vapour, and excited by fields due to continuous and alternating potentials (V). t was observed by a counter-sealer, and/or a galvanometer after rectification. +δi was observed under β-rays from a 50 millicurie Ra-Be source, and various frequency bands of the visible. The intensity (I) was varied over 30 times using the former, and 500 times with the latter. A 100% negative effect is observed near and above the threshold Vm; it decreases with increase of V. ± δi (disfavoured by a prolonged discharge) occurs within a restricted range of conditions, viz. low J and V. As these are increased, a sharp inversion equation follows which is fully reversible in respect of I and V. The minimum inversion intensity and the inversion potential vary in the order: violet < blue < green < yellow < red and, I2 H2 < air. ±δi is independe...