Anomalous transport and phonon renormalization in a chain with transverse and longitudinal vibrations

We study thermal transport in a chain of coupled atoms, which can vibrate in longitudinal as well as transverse directions. The particles interact through anharmonic potentials upto cubic order. The problem is treated quantum mechanically. We first calculate the phonon frequencies self-consistently taking into account the anharmonic interactions. We show that for all the modes, frequencies must have linear dispersion with wave-vector $q$ for small $q$ irrespective of their bare dispersions. We then calculate the phonon relaxation rates $\Gamma_i(q)$, where $i$ is the polarization index of the mode, in a self-consistent approximation based on second order perturbation diagrams. We find that the relaxation rate for the longitudinal phonon, $\Gamma_x(q) \propto q^{3/2}$, while that for the transverse phonon $\Gamma_y(q) \propto q^2$. The consequence of these results on the thermal conductivity $\kappa(N)$ of a chain of $N$ particles is that $\kappa(N) \propto N^{1/2}$

Continuous Functional Calculus for Quaternionic Bounded Normal Operators

In this article we give an approach to define continuous functional calculus for bounded quaternionic normal operators defined on a right quaternionic Hilbert space.Comment: Submitted to a journal. There was a gap in the previous version. We have corrected it and stated all the results for bounded cas

Effects of Interval Continuous and Alternate Pace Running on Cardio Respiratory Endurance

The purpose of the study was to find out the effects of interval continuous and alternate pace running on cardio respiratory endurance. To achieve this purpose, sixty men students in the department of physical Education and sports sciences, Annamalai university, Tamilnadu, India were selected as subjects at random. The selected subjects were divided into four equal groups of fifteen subjects each, such as interval running group, continuous running group, alternate pace running group and control group. The group I underwent interval training programme, Group II underwent continuous running programme and group III underwent alternate pace running for three days per week for twelve weeks. Group 1V acted as control group which did not participate any special training programmes apart from their regular physical education activities as per their curriculum. The age groups of the subjects were ranged from 18 to 24 years. Cardio respiratory endurance was selected as criterion variable and measured through Cooper’s 12 minutes run and walk test. All the subjects of four groups were tested on selected criterion variables at prior to and immediately training programme. The analysis of covariance revealed a significant adjusted post test mean (F = 113.63, p < 0.05). It is concluded that cardio respiratory fitness improved better in continuous method than interval and alternate pace method

An Effective Private Data storage and Retrieval System using Secret sharing scheme based on Secure Multi-party Computation

Privacy of the outsourced data is one of the major challenge.Insecurity of the network environment and untrustworthiness of the service providers are obstacles of making the database as a service.Collection and storage of personally identifiable information is a major privacy concern.On-line public databases and resources pose a significant risk to user privacy, since a malicious database owner may monitor user queries and infer useful information about the customer.The challenge in data privacy is to share data with third-party and at the same time securing the valuable information from unauthorized access and use by third party.A Private Information Retrieval(PIR) scheme allows a user to query database while hiding the identity of the data retrieved.The naive solution for confidentiality is to encrypt data before outsourcing.Query execution,key management and statistical inference are major challenges in this case.The proposed system suggests a mechanism for secure storage and retrieval of private data using the secret sharing technique.The idea is to develop a mechanism to store private information with a highly available storage provider which could be accessed from anywhere using queries while hiding the actual data values from the storage provider.The private information retrieval system is implemented using Secure Multi-party Computation(SMC) technique which is based on secret sharing. Multi-party Computation enable parties to compute some joint function over their private inputs.The query results are obtained by performing a secure computation on the shares owned by the different servers.Comment: Data Science & Engineering (ICDSE), 2014 International Conference, CUSA

Numerical study on energy absorbing characteristics of thin-walled tube under axial and oblique impact

AbstractEnergy absorbing characteristics (EAC) of thin wall tube during the impact are important in the automobile and aerospace industries. In this paper, energy absorbing characteristics such as mean force, peak force, energy absorption and crash force efficiency (CFE) of three different cross-sections (square, rectangular and circular) at three different thicknesses (2mm, 2.5mm and 4mm) were analyzed. The analysis was accomplished using ABAQUS/EXPLICIT, and aluminum alloy (AA6063) was used as a shell material. The result of impact (or) crash-worthiness against axial load indicates that the circular cross section of 2.5mm thickness is optimum. During the oblique (15°, 30°, 45°) impact, increasing the angle leads to less energy absorption. Also, Multilinear regression analysis was carried out to predict the energy absorption characteristics at 90°