Magnetocaloric effect and critical behavior near the paramagnetic to ferrimagnetic phase transition temperature in TbCo2-xFex

Magnetocaloric effect (MCE) in TbCo2-xFex has been studied by dc magnetization measurements.On substituting Fe in TbCo2, not only the magnetic transition temperature is tuned to room temperature, but also the operating temperature range for MCE is increased from 50 K for TbCo2 to 95 K for TbCo1.9Fe0.1. The maximum magnetic entropy change (-{\Delta}SM) for TbCo1.9Fe0.1 is found to be 3.7 J kg-1 K-1 for a 5 T field change, making it a promising candidate for magnetic refrigeration near room temperature. The temperature dependent neutron diffraction study shows a structural phase transition (from cubic to rhombohedral phase with lowering of temperature) which is associated with the magnetic phase transition and these transitions broaden on Fe substitution. To investigate the nature of the paramagnetic to ferrimagnetic phase transition, we performed a critical exponent study. From the derived values of critical exponents, we conclude that TbCo2 belongs to the 3D Heisenberg class with short-range interaction, while on Fe substitution it tends towards mean-field with long-range interaction. The derived values of critical exponents represent the phenomenological universal curve for the field dependence of {\Delta}SM, indicating that TbCo2 and TbCo1.9Fe0.1 belong to two different universality classes.Comment: 12 figure

Looking for the Top-squark at the Tevatron with four jets

The scalar partner of the top quark is relatively light in many models of supersymmetry breaking. We study the production of top squarks (stops) at the Tevatron collider and their subsequent decay through baryon-number violating couplings such that the final state contains no leptons. Performing a detector-level analysis, we demonstrate that, even in the absence of leptons or missing energy, stop masses upto 210 \gev/c^2 can be accessible at the Tevatron.Comment: 4 pages, 4 embedded figures, RevTe

Heavy landing of juveniles of lizardfish Saurida undosquamis (Richardson) at Visakhapatnam

Andhra Pradesh has a coastline of 974 km and continental shelf area of 33,227 km. The annual marine fish landings of the state ranged from 2,08,305 to 2, 33,900 t during 2006 to 2009 with an annual average landing of 2, 22,928 t. Highest catch of 2,33,900 t was observed in 2009 and lowest of 2,08,305 t in the year 2007. Among the demersal resources, lizardfish is one of the dominant group. Lizardfish is sold and consumed in both fresh and dried condition at Visakhapatnam and is preferred by poor people as a protein supplement and also used in value added products. Lizardfish is locally called ‘Badematta’ and it supports a regular fishery

Tuning the phase diagram of a Rosenzweig-Porter model with fractal disorder

The Rosenzweig-Porter (RP) model has garnered much attention in the last decade, as it is a simple analytically tractable model showing both ergodic-nonergodic extended and Anderson localization transitions. Thus, it is a good toy model to understand the Hilbert-space structure of many-body localization phenomenon. In our Letter, we present analytical evidence, supported by exact numerics, that demonstrates the controllable tuning of the phase diagram in the RP model by employing on-site potentials with a nontrivial fractal dimension instead of the conventional random disorder. We demonstrate that such disorder extends the fractal phase and creates an unusual dependence of fractal dimensions of the eigenfunctions. Furthermore, we study the fate of level statistics in such a system to understand how these changes are reflected in the eigenvalue statistics

Reference Ranges for Serum Uric Acid among Healthy Assamese People

This study was designed to establish reference ranges for serum uric acid among healthy adult Assamese population. Samples from 1470 aged 35–86 years were used to establish age and sex related reference range by the centile method (central 95 percentile) for serum uric acid level. There were 51% (n=754) males and 49% (n=716) females; 75.9% (n=1115) of them were from urban area and the rest 24.1% (n=355) were from the rural area. Majority of the population were nonvegetarian (98.6%, n=1450) and only 1.4% (n=20) were vegetarian. The mean age, weight, height, and uric acid of the studied group were 53.6±11.3 years, 62.6±10.5 kg, 160±9.4 cm, and 5.5±1.4 mg/dL, respectively. There is a statistically significant difference in the mean value of the abovementioned parameters between male and female. The observed reference range of uric acid in the population is 2.6–8.2 mg/dL which is wider than the current reference range used in the laboratory. Except gender (P<0.0001), we did not find any significant relation of uric acid with other selected factors

Employee Quality of Life in Office Automation Through Service Innovation: A Fuzzy Approach

Managers have to make different decisions about using different types of information at the same time. Managing the performance of employees and quality of life in printing industries and Information Technology Parks, individually or collectively is an important aspect of decision making. Effectively managing an organization's human resources and evaluating employees to support personal development, improved organizational performance, and input into the organization's strategy depend on performance appraisals. This is due to the absence of quantitative and systematic techniques. The problems include improper data, qualitative and quantitative measurements, and the performance evaluation is the main task for the industrial sectors. Fuzzy control is used to calculate the overall achievement index by aggregating the performance results for some selected parameters and presenting them as numerical values, which will certainly facilitate the evaluation of the appraisal calculation of the human resources staff. Consequently, the current research utilizes the characteristics of data technologies and provides a method to quantitatively and automatically assess employee performance in office automation. The results show that an independent aspect of workplace performance appraisal is the automated employee performance appraisal system

Influence of Organisational Culture on Decision Making in Select Public Sector Enterprises

Public sector Enterprises in India, particularly the Central Government owned were designated as “Temples of Modern India” by Pandit Jawaharlal Nehru, the first prime Minister of India. They were started with clear aim of providing employment, and supplying goods at affordable prices besides the larger goal of industrialization and balanced growth. It did serve the purpose till liberalization was initiated in 1990. The globalization and liberalization brought about extreme pressure on hitherto protected industries to take on competition. The culture developed over five decades was precipitously called upon to take on the changes that were taking place in the environment forcing many PSEsto turn red unable to deal with competition. This study attempts to understand the organisational culture that was developed over a period of 50 years and its ability to cope with changes through effective and efficient decision making by executives and by their leadership or management style and to a certain extent the presence of unique PSE ecosystem. It is being explored that notwithstanding the individual differences in decision making, organisational culture forces all executives t

Study of Kalman, Extended Kalman and Unscented Kalman Filter (An Approach to Design a Power System)

The accurate measurement of harmonics level is essential for designing harmonic filters,monitoring the stress to which the power system devices are subjected due to harmonics and specifying digital filtering techniques for phasor measurements for relaying. This project presents an integrated approach to design an optimal estimator of harmonic components of a power network in the presence of frequency variations. This has led to the study of Kalman, Extended Kalman and Unscented Kalman filter characteristics and a subsequent implementation of the study to design the optimal filter. We have employed the Extended Kalman filter and Unscented Kalman filter algorithms to estimate the power system voltage magnitude in the presence of random noise and distortions again taking into account the measurement noise. Kalman filter being an optimal estimator track the signal corrupted with noise and bearing harmonic distortion quite accurately. Adaptive tracking of harmonic components of a power system can easily be done using these algorithm. The proposed approaches are tested for only static signals. For a test signal both EKF and UKF algorithms are used and the results are compared