Indian Institute of Technology Palakkad&nbsp;(IIT Palakkad or IIT PKD) is a public autonomous&nbsp;engineering&nbsp;and&nbsp;research&nbsp;institute located in&nbsp;Palakkad,&nbsp;Kerala. It was&nbsp;one of the five new&nbsp;IITs&nbsp;proposed in the&nbsp;2014 Union budget of India. The campus was inaugurated on 3 August 2015. The institute has 94 faculty, 978 students, and 63 non-teaching staffs.

IT Palakkad currently offers four-year Bachelor of Technology (B.Tech) and two years MS programmes in 8 different engineering disciplines including&nbsp;Computer Science, Electrical, Mechanical, Civil among others.

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IIT Palakkad

Department of Mechanical Engineering

IIT Kharagpur

Surface modification of Aluminium by electrical discharge coating in EDM

Hydrodynamic parameters play a major role in the dynamics and control of Autonomous Underwater Vehicles (AUVs). The performance of an AUV is dependent on the parameter variations and a proper understanding of these parametric influences is essential for the design, modeling, and control of high-performance AUVs. In this paper, the sensitivity of hydrodynamic parameters on the control of a flatfish type AUV is analyzed using robust design techniques such as Taguchi's design method and statistical analysis tools such as Pareto-ANOVA. Since the pitch angle of an AUV is one of the crucial variables in the control applications, the sensitivity analysis of pitch angle variation is studied here. Eight prominent hydrodynamic coefficients are considered in the analysis. The results show that there are two critical hydrodynamic parameters, that is, hydrodynamic force and hydrodynamic pitching moment in the heave direction that influence the performance of a flatfish type AUV. A near-optimal combination of the parameters was identified and the simulation results have shown the effectiveness of the method in reducing the pitch error. These findings are significant for the design modifications as well as controller design of AUVs. Copyright © 2009 M. Santhakumar et al.

World University root node

Fulltext

International Journal of Quality, Statistics, and Reliability

Analysis of parameter sensitivity using robust design techniques for a flatfish type autonomous underwater vehicle

We have been exploring the use of a deep cavity cavitand known by the trivial name 'octa acid' as a photochemical reaction, cavity for manipulating photochemical and photophysical properties of organic molecules. In the current study, we have monitored the micropolarity of the interior of the cavitand by recording the fluorescence of five different organic probes. They all indicate that the interior of octa acid capsuleplex (2:1, H/G complex) is nonpolar and does not contain water molecules in spite of the complex being present in water. The nature of the octa acid-probe complex in each case has been characterized by 1H NMR data to be a 2:1 capsuleplex. Photophysical and 1H NMR experiments were employed to probe the factors that control the structure of the complex, 2:2, 2:1, and 1:1. The data we have on hand suggest that the structure of the host/guest complex depends on the size and hydrophobicity of the guest molecule. © 2009 American Chemical Society.

Department of Chemistry

Langmuir

Cavitand octa acid forms a nonpolar capsuleplex dependent on the molecular size and hydrophobicity of the guest

CD4+CD25+ regulatory T cells (Tregs) play a critical role in preventing immune aggression. One way in which Tregs exert immune surveillance activities is by modifying the function of antigen presenting cells (APCs) such as dendritic cells, macrophages, and B cells. Tregs can induce apoptosis of APCs or inhibit their activation and function, thereby regulating subsequent innate and adaptive immune responses. These actions of Tregs are mediated by both soluble factors (interleukin [IL]-10, transforming growth factor-β, perforins, granzymes) and cell-associated molecules (cytotoxic T lymphocyte antigen 4, lymphocyte activation gene-3, CD18, neuropilin-1, LFA-1/CD11a, CD39), of which cytotoxic T lymphocyte antigen 4 has a key role. However, in autoimmunity, chronically activated APCs under the influence of intracellular signaling pathways, such as phosphatidyl inositol 3 kinase, JAK-STAT, MAPK, and nuclear factor-κB pathways, can escape surveillance by Tregs, leading to the activation of T cells that are refractory to suppression by Tregs. Moreover, APCs and APC-derived inflammatory cytokines such as tumor necrosis factor, IL-6, IL-1β, and IL-23 can render Tregs defective and can also reciprocally enhance the activity of the IL-17-producing pathogenic Th17 T cell subset. Emerging knowledge of the importance of APC-Treg interactions in maintaining immune tolerance and aberrations in this cross talk in autoimmune diseases provides a rationale for therapeutic approaches specifically targeting this axis of the immune system. Copyright © American Society for Investigative Pathology.

Biological Sciences and Engineering

American Journal of Pathology

Surveillance of antigen-presenting cells by CD4+CD25+ regulatory T cells in autoimmunity: Immunopathogenesis and therapeutic implications

The posters presented at the 6th International Immunoglobulin Symposium covered a wide range of fields and included both basic science and clinical research. From the abstracts accepted for poster presentation, 12 abstracts were selected for oral presentations in three parallel sessions on immunodeficiencies, autoimmunity and basic research. The immunodeficiency presentations dealt with novel, rare class-switch recombination (CSR) deficiencies, attenuation of adverse events following IVIg treatment, association of immunoglobulin (Ig)G trough levels and protection against acute infection in patients with X-linked agammaglobulinaemia (XLA) and common variable immunodeficiency (CVID), and the reduction of class-switched memory B cells in patients with specific antibody deficiency (SAD). The impact of intravenous immunoglobulin on fetal alloimmune thrombocytopenia, pregnancy and postpartum-related relapses in multiple sclerosis and refractory myositis, as well as experiences with subcutaneous immunoglobulin in patients with multi-focal motor neuropathy, were the topics presented in the autoimmunity session. The interaction of dendritic cell (DC)-SIGN and α2,6-sialylated IgG Fc and its impact on human DCs, the enrichment of sialylated IgG in plasma-derived IgG, as wells as prion surveillance and monitoring of anti-measles titres in immunoglobulin products, were covered in the basic science session. In summary, the presentations illustrated the breadth of immunoglobulin therapy usage and highlighted the progress that is being made in diverse areas of basic and clinical research, extending our understanding of the mechanisms of immunoglobulin action and contributing to improved patient care. © 2009 British Society for Immunology.

Clinical and Experimental Immunology

6th International Immunoglobulin Symposium: Poster presentations

A recent theoretical model developed by Imparato of the experimentally measured heat and work effects produced by the thermal fluctuations of single micron-sized polystyrene beads in stationary and moving optical traps has proved to be quite successful in rationalizing the observed experimental data. The model, based on the overdamped Brownian dynamics of a particle in a harmonic potential that moves at a constant speed under a time-dependent force, is used to obtain an approximate expression for the distribution of the heat dissipated by the particle at long times. In this paper, we generalize the above model to consider particle dynamics in the presence of colored noise, without passing to the overdamped limit, as a way of modeling experimental situations in which the fluctuations of the medium exhibit long-lived temporal correlations, of the kind characteristic of polymeric solutions, for instance, or of similar viscoelastic fluids. Although we have not been able to find an expression for the heat distribution itself, we do obtain exact expressions for its mean and variance, both for the static and for the moving trap cases. These moments are valid for arbitrary times and they also hold in the inertial regime, but they reduce exactly to the results of Imparato in appropriate limits. © 2009 The American Physical Society.

Physical Review E - Statistical, Nonlinear, and Soft Matter Physics

Brownian particles in stationary and moving traps: The mean and variance of the heat distribution function

A new approach to implement computationally efficient reconfigurable filter banks for multi-standard wireless receivers is presented in this paper. Based on the concepts of tree-structured quadrature mirror filter bank (TQMFB) and coefficient decimation approach, a reconfigurable and efficient tree-structured non-uniform filter bank (TNFB) is proposed in this paper. The proposed filter bank is designed to extract channels of non-uniform bandwidths with reduced complexity when compared to TQMFB. Each stage of the proposed filter bank consists of a modal filter and a complementary delay to obtain the low-pass and high-pass channels respectively. Design examples show that the proposed TNFB offers an average multiplication rate reduction of 69% over the TQMFB. ©2009 IEEE.

Department of Electrical Engineering

Proceedings - IEEE International Symposium on Circuits and Systems

A tree-structured non-uniform filter bank for multi-standard wireless receivers

We study the generation of defects when a quantum spin system is quenched through a multicritical point by changing a parameter of the Hamiltonian as t/τ, where τ is the characteristic timescale of quenching. We argue that when a quantum system is quenched across a multicritical point, the density of defects (n) in the final state is not necessarily given by the Kibble-Zurek scaling form n∼1/τdν/(zν+1), where d is the spatial dimension, and ν and z are respectively the correlation length and dynamical exponent associated with the quantum critical point. We propose a generalized scaling form of the defect density given by n∼1/τd/(2z 2), where the exponent z2 determines the behavior of the off-diagonal term of the 2 × 2 Landau-Zener matrix at the multicritical point. This scaling is valid not only at a multicritical point but also at an ordinary critical point. © 2009 IOP Publishing Ltd.

Department of Physics

Journal of Statistical Mechanics: Theory and Experiment

Defect production due to quenching through a multicritical point

The composite material shafts have been sought as new potential candidates for replacement of the conventional metallic shafts in many applications. These shafts are proved to have not only lighter in weight but also have greater strength. However, detailed dynamic studies on the effects of different materials, speeds and unbalance response are required, particularly with respect to the damping present due to the composite material. The main aim of the paper is to estimate the damping in rotor system consists of a composite solid shaft. The study is carried out to analyze the dynamic behaviour at different speeds and for different materials such as glass/epoxy, carbon/epoxy. Three different methodologies have been carried out for determining the damping of the composite shaft- rotor. The first one is to measure the signal at any speed, with impact hammer and get the logarithmic decay curve at that speed. From this the damping was estimated. The second method is to use half-power method to estimate the damping from the response of the rotor. In third methodology force sensors are used to get the unbalance force of the system and consequently hysteresis loops are obtained between the force and displacement for different speeds to get the equivalent damping. Simultaneously the Finite Element Analysis of the same rotor system using ANSYS software is carried out for eigenfrequencies. These results for different materials are compared with those of experiments.

16th International Congress on Sound and Vibration 2009, ICSV 2009

Damping estimation and dynamic analysis of a composite shaft - Rotor system

Hydrodynamic parameters play a major role in the dynamics and control of Autonomous Underwater Vehicles (AUV). The performance of an AUV is dependent on the parameter variations and a proper understanding of these parametric influences is essential for the design, modelling and control of high performance AUVs. In this paper, a six sigma framework for the sensitivity analysis of a flatfish type AUV is presented. Robust design techniques such as Taguchi's design method and statistical analysis tools such as Pareto-ANOVA, and ANOVA are used to identify the hydrodynamic parameters influencing the dynamic performance of an AUV. In the initial study, it is found that when the vehicle commanded in forward direction, it is in bow down configuration which is unacceptable for AUV motion. This is because of the vehicle buoyancy and shape of the vehicle. So the sensitivity analysis of pitch angle variation is studied by using robust design techniques. Six prominent hydrodynamic coefficients are considered for the analysis. The results show that there are three critical hydrodynamic parameters such as buoyancy, added mass, and hydrodynamic moment in heave motion that influence the performance of a flat fish type AUV. These findings are significant in the design modifications as well as controller design of AUV. Copyright © 2009 SAE International.