The Contributions of Open and Distance Learning (ODL) Towards Job Performance of Veterinary Practitioners

An analytical study was conducted on Open and Distance Learning (ODL) programmes by veterinary university, Chennai for veterinary practitioners in Erode, Salem and Coimbatore districts of Tamil Nadu, India. Field veterinarians working in the public dispensaries / hospitals formed the sample for the study. The data was collected by mailing questionnaires to the respondents. The study revealed that the ODL courses effectively enhanced the job performance of the veterinarians in the areas of diagnosis (57.14 per cent) followed by medical treatment (49.86 per cent) at a frequency ranging from often to most often. Three-fourths (75.00 per cent) of the participants and non-participants (87.50 per cent) had medium to high level of job performance. The ‘Z’ test was statistically non-significant for job performance between the participants and the non-participants. Among the 14 independent variables, access to computer and training exposure was found to have a highly significant relationship with job performance in case of participants while all other variables were non-significant. The results would help the ODL developers to improve the contents and facilitate better delivery of distance education courses, so as to enhance the job performance of the veterinarians. [Editor\u27s Note] This article was published on March 29, 201

Stability of natural convection in a vertical dielectric couple stress fluid layer in the presence of a horizontal AC electric field

The combined effect of couple stresses and a uniform horizontal AC electric field on the stability of buoyancy-driven parallel shear flow of a vertical dielectric fluid between vertical surfaces maintained at constant but different temperatures is investigated. Applying linear stability theory, stability equations are derived and solved numerically using the Galerkin method with wave speed as the eigenvalue. The critical Grashof number Gc, the critical wave number ac and the critical wave speed cc are computed for wide ranges of couple stress parameter  Λc, AC electric Rayleigh number Rea and the Prandtl number Pr. Based on these parameters, the stability characteristics of the system are discussed in detail. The value of Prandtl number at which the transition from stationary to travelling-wave mode takes place is found to be independent of AC electric Rayleigh number even in the presence of couple stresses but increases significantly with increasing Λc. Moreover, the effect of increasing Rea is to instill instability, while the couple stress parameter shows destabilizing effect in the stationary mode but it exhibits a dual behavior if the instability is via travelling-wave mode. The streamlines and isotherms presented demonstrate the development of complex dynamics at the critical state

Numerical investigation of electrohydrodynamic instability in a vertical porous layer

The electrohydrodynamic instability of a vertical dielectric fluid saturated Brinkman porous layer whose vertical walls are maintained at different temperatures is considered. An external AC electric field is applied across the vertical porous layer to induce an unstably stratified electrical body force. The stability eigenvalue equation is solved numerically using the Chebyshev collocation method. The presence of inertia is found to instill instability on the system and the value of modified Darcy�Prandtl number PrD at which the transition from stationary to travelling-wave mode takes place is independent of the AC electric field but increases considerably with an increase in the value of Darcy number Da. The presence of AC electric field promotes instability but its effect is found to be only marginal. Although the flow is stabilizing against stationary disturbances with increasing Da, its effect is noted to be dual in nature if the instability is via travelling-wave mode. The streamlines and isotherms for various values of physical parameters at their critical state are presented and analyzed. Besides, energy norm at the critical state is also computed and found that the disturbance kinetic energy due to surface drag, viscous force and dielectrophoretic force have no significant effect on the stability of fluid flow. © 2017 Elsevier Inc

Boundary and inertia effects on the stability of natural convection in a vertical layer of an anisotropic Lapwood�Brinkman porous medium

The stability of natural convection in a fluid-saturated vertical anisotropic porous layer is investigated. The vertical rigid walls of the porous layer are maintained at different constant temperatures, and anisotropy in both permeability and thermal diffusivity is considered. The flow in the porous medium is described by the Lapwood�Brinkman model, and the stability of the basic flow is analysed numerically using Chebyshev collocation method. The presence of inertia is to inflict instability on the system and in the absence of which the system is always found to be stable. The mechanical and thermal anisotropies exhibit opposing contributions on the stability characteristics of the system. The mode of instability is interdependent on the values of Prandtl number and thermal anisotropy parameter, while it remains unaltered with the mechanical anisotropy parameter. The effect of increasing Prandtl and Darcy numbers shows a destabilizing effect on the system. Besides, simulations of secondary flow and energy spectrum have been analysed for various values of physical parameters at the critical state. © 2017, Springer-Verlag Wien

Effect of Horizontal Alternating Current Electric Field on the Stability of Natural Convection in a Dielectric Fluid Saturated Vertical Porous Layer

The stability of natural convection in a dielectric fluid-saturated vertical porous layer in the presence of a uniform horizontal AC electric field is investigated. The flow in the porous medium is governed by Brinkman-Wooding-extended-Darcy equation with fluid viscosity different from effective viscosity. The resulting generalized eigenvalue problem is solved numerically using the Chebyshev collocation method. The critical Grashof number G(c), the critical wave number a(c), and the critical wave speed c(c) are computed for a wide range of Prandtl number Pr, Darcy number Da, the ratio of effective viscosity to the fluid viscosity K, and AC electric Rayleigh number R-ea. Interestingly, the value of Prandtl number at which the transition from stationary to traveling-wave mode takes place is found to be independent of R-ea. The interconnectedness of the Darcy number and the Prandtl number on the nature of modes of instability is clearly delineated and found that increasing in Da and R-ea is to destabilize the system. The ratio of viscosities K shows stabilizing effect on the system at the stationary mode, but to the contrary, it exhibits a dual behavior once the instability is via traveling-wave mode. Besides, the value of Pr at which transition occurs from stationary to traveling-wave mode instability increases with decreasing K. The behavior of secondary flows is discussed in detail for values of physical parameters at which transition from stationary to traveling-wave mode takes place

Effect of Horizontal AC Electric Field on the Stability of Natural Convection in a Vertical Dielectric Fluid Layer

The stability of buoyancy-driven parallel shear flow of a dielectric fluid confined between differentially heated vertical plates is investigated under the influence of a uniform horizontal AC electric field. The resulting generalized eigenvalue problem is solved numerically using Chebyshev collocation method with wave speed as the eigenvalue. The critical Grashof number Gc, the critical wave number αc and the critical wave speed cc are computed for wide ranges of AC electric Rayleigh number Rea and the Prandtl number Pr. Based on these parameters, the stability characteristics of the system are discussed in detail. It is found that the AC electric Rayleigh number is to instill instability on convective flow against both stationary and travelling-wave mode disturbances. Nonetheless, the value of Prandtl number at which the transition from stationary to travelling-wave mode takes place is found to be independent of AC electric Rayleigh number. The streamlines and isotherms presented demonstrate the development of complex dynamics at the critical state

Stability of natural convection in a vertical couple stress fluid layer

The stability of buoyancy-driven parallel shear flow of a couple stress fluid confined between vertical plates is investigated by performing a classical linear stability analysis. The plates are maintained at constant but different temperatures. A modified Orr-Sommerfeld equation is derived and solved numerically using the Galerkin method with wave speed as the eigenvalue. The critical Grashof number Gc, critical wave number ac and critical wave speed cc are computed for wide ranges of couple stress parameter Îc and the Prandtl number Pr. Based on these parameters, the stability characteristics of the system are discussed in detail. The value of Prandtl number, at which the transition from stationary to travelling-wave mode takes place, increases with increasing Î c. The couple stress parameter shows destabilising effect on the convective flow against stationary mode, while it exhibits a dual behaviour if the instability is via travelling-wave mode. The streamlines and isotherms presented demonstrate the development of complex dynamics at the critical state. © 2014 Elsevier Ltd. All rights reserved

Wolbachia Association and its Phylogenetic Affiliation of Brugia Malayi Parasites from India

Wolbachia have established a mutualistic association with filarial nematodes and has a phenomenal implication in its normal development, reproduction and survival. Elimination of Wolbachia by tetracycline class of antibiotic compounds have been suggested and successfully implemented for the treatment of lymphatic filarial parasites. Thereby, is necessary to assess the prevalence of the Wolbachia in B. malayi before such new strategies are employed, across the world. In the present communication, the presence of Wolbachia and phylogenetic affiliation in B. malayi collected from Sevagram, Maharashtra, India, has been addressed

Railway track degradation modelling using dynamic multi-regression to predict failure patterns

Railway tracks degrade and may eventually break down due to several operational and environmental impacts that affect the rails’ reliability. The most common type of railhead defect is called the rail squat, which cost Network Rail an estimate of approximately 3.9 million pounds annually. Squat defects are minor subsurface laminations that run diagonally down the running surface and spread laterally and longitudinally over and along the rail tracks (Li, Zili et al., 2008a; Li, Zili et al., 2008b; Li, Z., 2009). The occurrence of squat defects has a significant impact on the track performance, leading to speed restrictions, delays, and cancellation of in-service train operations and hence penalties for infrastructure owners. To ensure the performance and efficiency of service operations and more reliable railway infrastructure, the UK is investing in railway modernization projects to meet this demand (Rail director April 2023, 2023; MyBib Contributors, 2019).This study uses a Dynamic Multiple linear regression to model the relationship between squat defects and influential parameters such as track length, maximum permissible speed, maximum axle load, estimated million gross tonnage, tamping frequency, rail grinding frequency, and corrugation frequency detection. A hazard model is proposed and used to predict transition probabilities between defect and failure. This research evaluated six years of data acquired from network rail on squats defects, grinding maintenance, and corrugation faults across the UK railway network. The dynamic Markov model is used within the scope of the hazard model to determine the transition probabilities of squat defects propagation. A complete squat data analysis is performed by comparing the efficiency of the rail gridding maintenance regime to the cumulative squat defect frequency against the number of repair operations. An example simulation is shown to anticipate the time to breakdown of railway track systems

Stability of fluid flow in a Brinkman porous medium-A numerical study

The stability of fluid flow in a horizontal layer of Brinkman porous medium with fluid viscosity different from effective viscosity is investigated. A modified Orr-Sommerfeld equation is derived and solved numerically using the Chebyshev collocation method. The critical Reynolds number Re-c, the critical wave number alpha(c) and the critical wave speed c(c) are computed for various values of porous parameter and ratio of viscosities. Based on these parameters, the stability characteristics of the system are discussed in detail. Streamlines are presented for selected values of parameters at their critical state