Deformation Response of Some Earth and Rock-fill Dams

Vertical compressional data obtained from 10 earth and earth rock fill darns built in India has been analysed for during construction and post-construction response. The performance of these darns has been compared with some darns built in USA wherein the construction practices have been similar. The contributions of various factors, namely height of embankment, gradation and plasticity of soil, and placement conditions of moisture and density have been examined. A major portion of the total compression occurred by the end of construction. These compressions were found to be the functions of the height of the embankment. Both the compressions across and along the valley have been found to be small

Performance of Some Tunnels in Squeezing Rocks of Himalayas

Data regarding the performance of three tunnelling projects in the Himalayan region has been collected. It is seen that rock loads or deformations calculated on the basis of Barton, Bieniawski or RMR approach do not match the field data. A mathematical model has been developed incorporating modifications in the approach of Brown et.al of rock-support interaction, using elastic-strain softening-plastic ground characteristics. A non-linear relationship between radial and tangential strains around the tunnel has been considered and the method of calculation of stresses and deformations altered to incorporate exact integration of the governing differential equation for a thin cylindrical annulus replacing finite difference approximation. It is seen that a closer match and a more rational explanation of the observed data from the tunnelling project is provided by the mathematical model

Mining the Web Data for Classifying and Predicting Users’ Requests

Consumers are the most important asset of any organization. The commercial activity of an organization booms with the presence of a loyal customer who is visibly content with the product and services being offered. In a dynamic market, understanding variations in client’s behavior can help executives establish operative promotional campaigns. A good number of new consumers are frequently picked up by traders during promotions. Though, several of these engrossed consumers are one-time deal seekers, the promotions undeniably leave a positive impact on sales. It is crucial for traders to identify who can be converted to loyal consumer and then have them patronize products and services to reduce the promotion cost and increase the return on investments. This study integrates a classifier that allows prediction of the type of purchase that a customer would make, as well as the number of visits that he/she would make during a year. The proposed model also creates outlines of users and brands or items used by them. These outlines may not be useful only for this particular prediction task, but could also be used for other important tasks in e-commerce, such as client segmentation, product recommendation and client base growth for brands

Patterns of electro-magnetic response in topological semi-metals

Topological semimetals are gapless states of matter which have robust and unique electromagnetic responses and surface states. In this thesis, we consider semimetals which have point like Fermi surfaces in various spatial dimensions $D=1,2,3$ which naturally occur in the transition between $n$th order weak topological insulators and a trivial insulating phase. These semimetals include those of Dirac and Weyl type. We construct these phases by layering strong topological insulator phases in lower dimensions. This perspective helps us understand their effective response field theory, which is generally characterized by a $n$-form which represents a source of Lorentz violation and can be read off from the location of the singular points in momentum space and the helicities/chiralities of the singularities. We motivate and derive effective response actions for the 2D and 3D Dirac semi-metals, the Weyl semimetal, the 3D line node semi-metal and the 3D mirror protected topological crystalline insulator

Storing Drinking-water in Copper pots Kills Contaminating Diarrhoeagenic Bacteria

Microbially-unsafe water is still a major concern in most developing countries. Although many water-purification methods exist, these are expensive and beyond the reach of many people, especially in rural areas. Ayurveda recommends the use of copper for storing drinking-water. Therefore, the objective of this study was to evaluate the effect of copper pot on microbially-contaminated drinking-water. The antibacterial effect of copper pot against important diarrhoeagenic bacteria, including Vibrio cholerae O1, Shigella flexneri 2a, enterotoxigenic Escherichia coli, enteropathogenic E. coli, Salmonella enterica Typhi, and Salmonella Paratyphi is reported. When drinking-water (pH 7.83±0.4; source: ground) was contaminated with 500 CFU/mL of the above bacteria and stored in copper pots for 16 hours at room temperature, no bacteria could be recovered on the culture medium. Recovery failed even after resuscitation in enrichment broth, followed by plating on selective media, indicating loss of culturability. This is the first report on the effect of copper on S. flexneri 2a, enteropathogenic E. coli, and Salmonella Paratyphi. After 16 hours, there was a slight increase in the pH of water from 7.83 to 7.93 in the copper pots while the other physicochemical parameters remained unchanged. Copper content (177±16 ppb) in water stored in copper pots was well within the permissible limits of the World Health Organization. Copper holds promise as a point-of-use solution for microbial purification of drinking-water, especially in developing countries

Bounds and error control for eigenvalues

Control and estimation of errors are important but difficult aspects of any analysis from which the numerical results are necessarily approximate. The order of difficulty is greater for local or distributed quantities like stresses and displacements than for global Of integrated parameter~ like eigenvalues and stiffnesses. To really bound a desired quantity between a pair of dose upper and lower bounds one should obtain either an oscillatory but clear convergence or, preferably, two rapidly converging sequences one from above and the other from below. Application of the two complementary variational principles of energy and complimentary energy, when both are possible to apply, do yield upper and lower bound approximations. But these or other alternate methods are generally expensive. On the other hand it would be advantageous if one basic procedure could be perturbed in a simple manner to provide both lower and upper bounds and to refine the solution and control the errors without undue effort. This paper discusses this concept and presents three powerful methods to closely bound any desired parameter in a problem. These are particularly valuable for eigenvalue problems