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

This paper proposes a lying/sitting type lower-limb rehabilitation robot based on a three degrees of freedom spatial parallel kinematic manipulator namely “The Orthoglide” along with an actuated rotational degree of freedom at the end-effector for the purpose of lower-limb rehabilitation treatments. This rehabilitation robot is an end-effector/foot-plate based mechanism which controls the ankle-joint movements to assist physiotherapists in performing therapeutic treatments along with a passive orthosis (supporting system). The conceptual and detail design of the rehabilitation device is presented along with its kinematics. Further, the functional validation of the proposed robot in terms of the kinematic motion capabilities to provide physiological motions like knee flexion-extension, hip adduction-abduction and hip flexion-extension are also investigated. The required safety features for the proposed rehabilitation robot in terms of mechanical constraints and non-actuated joints are also discussed. © 2021, Springer Nature Singapore Pte Ltd.

World University root node

Department of Mechanical Engineering

Lecture Notes in Mechanical Engineering

A New Sitting-Type Lower-Limb Rehabilitation Robot Based on a Spatial Parallel Kinematic Machine

This research work emphasizes the equations of motion of a ground-based vehicle-manipulator system that constitutes of a spatial six degree of freedom serial manipulator and is modelled considering the dynamic coupling and other effects. Subsequently, a robust double-loop motion control scheme is applied for the end effector trajectory tracking of the vehicle-manipulator system. Simulation experiments based on real-time system parameters are accomplished to elucidate the essence of the recommended control scheme. The outcomes of this work emphasize that the proffered motion control scheme is suited to the similar kinematically redundant robotic systems and is effective even in the existence of unknown external disturbances and system uncertainties. © 2021, The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

Double-Loop Robust Motion Control of a Ground-Based Vehicle-Manipulator System

Alloy-706 is a newly introduced exceptional class of turbine wheel alloy for high-performance aero-engine. To precisely measure the WEDM performance of complex aero-engine parts, the RSM-based TLBO algorithm is proposed in the current study. Morphology, topography, recast layer thickness, and roughness parameters of machined surface are studied to examine the surface integrity of aero-engine components. Better surface morphology, smoother topography, low roughness value, and minimum recast layer are observed at low pulse duration, high pulse-off period, and high servo voltage. RSM is used for statistical modeling of removal rate and average roughness. Then, these models are used in TLBO algorithm for individual and multiple performance optimizations. The Pareto optimal solutions are obtained for lower roughness value and highest removal rate. The microscopic investigation represents a considerable number of melted droplets, micro-holes, and craters on the WEDM-cut surface due to high energy discharge pulses followed by improper flushing of molten material. © 2021 Elsevier Ltd

Measurement: Journal of the International Measurement Confederation

Measurement of WEDM performance characteristics of aero-engine alloy using RSM-based TLBO algorithm

The present study aims to precisely manufacture the turbine wheel slot using a novel trim-offset approach of wire-electrical-discharge-machining (WEDM) in order to overcome the challenges of a conventional broaching process. Two dimensional model of turbine wheel slot is prepared in ‘ELCAM’ software to generate the computer-numerical-control (CNC) code of fir-tree-profile geometry. The experimental plan based on a trim-offset approach is executed to minimize the thermal damage and to improve the surface fatigue strength, which is most desirable for a long operating life of the jet engine. An average cutting speed of ~1.5 mm/min is observed for rough-cut and ~5 mm/min for trim-cut operation. Six categories of wires are used to manufacture the turbine wheel slots without any wire breakage and gap-short issue. The fabricated profile slots have demonstrated an average roughness (Ra) of 0.65 μm, profile accuracy within ±5 μm, minimum hardness alteration (34.87 Hv), and negligible recast layer (<5 μm) using B-150 wire and fulfilled the essential requirements of the gas turbine industries. Compared to wire-electrochemical-machining (WECM), WEDM trim-offset approach is quite advantageous and should be beneficial for the researchers working in ‘Precision machining of aerospace materials’. © 2021 Elsevier Inc.

Precision Engineering

Precision manufacturing of turbine wheel slots by trim-offset approach of WEDM

Annotating words in a historical document image archive for word image recognition purpose demands time and skilled human resource (like historians, paleographers). In a real-life scenario, obtaining sample images for all possible words is also not feasible. However, Zero-shot learning methods could aptly be used to recognize unseen/out-of-lexicon words in such historical document images. Based on previous state-of-the-art methods for word spotting and recognition, we propose a hybrid representation that considers the character’s shape appearance to differentiate between two different words and has shown to be more effective in recognizing unseen words. This representation has been termed as Pyramidal Histogram of Shapes (PHOS), derived from PHOC, which embeds information about the occurrence and position of characters in the word. Later, the two representations are combined and experiments were conducted to examine the effectiveness of an embedding that has properties of both PHOS and PHOC. Encouraging results were obtained on two publicly available historical document datasets and one synthetic handwritten dataset, which justifies the efficacy of “Phos” and the combined “Pho(SC)” representation. © 2021, Springer Nature Switzerland AG.

Department of Data Science

Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)

Pho(SC)Net: An Approach Towards Zero-Shot Word Image Recognition in Historical Documents

This chapter introduces the recent advancements made in the electrochemical machining (ECM) technology as regards to the experimental setup, tool electrode, electrolyte solution, modeling and optimization of the process. The chapter also introduces the different variants of ECM, which are developed either by assisting with laser, ultrasonic and abrasive particles or by combining with grinding, honing, laser and spark erosion machining with the aim to improve the efficiency, stability and performance of existing classical ECM technique. Finally, the recent developments and future trends of the ECM process are presented.

Advanced Machining and Finishing

Advancements in electrochemical machining

The eternal vertex cover problem is a variant of the classical vertex cover problem defined in terms of an infinite attacker–defender game played on a graph. In each round of the game, the defender reconfigures guards from one vertex cover to another in response to a move by the attacker. The minimum number of guards required in any winning strategy of the defender when this game is played on a graph G is the eternal vertex cover number of G, denoted by evc(G). It is known that given a graph G and an integer k, checking whether evc(G)≤k is NP-hard. Further, it is known that for any graph G, mvc(G)≤evc(G)≤2mvc(G), where mvc(G) is the vertex cover number of G. Though a characterization is known for graphs for which evc(G)=2mvc(G), a characterization of graphs for which evc(G)=mvc(G) remained as an open problem, since 2009. We achieve such a characterization for a class of graphs that includes chordal graphs and internally triangulated planar graphs. For biconnected chordal graphs, our characterization leads to a polynomial time algorithm for precisely determining evc(G) and an algorithm for determining a safe strategy for guard movement in each round of the game using only evc(G) guards. Though the eternal vertex cover problem is only known to be in PSPACE in general, it follows from our new characterization that the problem is in NP for locally connected graphs, a graph class which includes all biconnected internally triangulated planar graphs. We also provide reductions establishing NP-completeness of the problem for biconnected internally triangulated planar graphs. As far as we know, this is the first NP-completeness result known for the problem for any graph class. © 2021 Elsevier B.V.

Department of Computer Science and Engineering

Discrete Applied Mathematics

On graphs whose eternal vertex cover number and vertex cover number coincide

Lymphatic filariasis (LF) is a debilitating parasitic disease caused by filarial parasites and it is prevalent across the underprivileged population throughout the globe. The inadequate efficacy of the existing treatment options has provoked the conception of alternative strategies, among which immunotherapy is steadily emerging as a promising option. Herein, we demonstrate the efficacy of an antibody-based immunotherapeutic approach in an experimental model of filariasis, i.e., Wistar rat infected with Setaria cervi (a model filarial parasite). The polyclonal antibodies were raised against filarial surface antigen bestrophin protein (FSAg) in mice using the purified Wuchereria bancrofti FSAg. The adoptive transfer of anti-FSAg antibody-containing serum resulted in the significant reduction of parasite burden in filaria-infected rats. Intriguingly, anti-FSAg sera-treated animals also displayed a reduction in the level of proinflammatory cytokines as compared to the infected but untreated group. Furthermore, our in silico immunoinformatics data revealed eight Bcell epitopes and several T-cell epitopes in FSAg and these epitopes were linked to form a refined antigen in silico. The immune simulation suggested IgM and IgG1 as the predominant immunoglobulins induced in response to FSAg. Taken together, our experimental and simulation data collectively indicated a therapeutic potential of anti-FSAg sera against LF. © 2021 by the author. Licensee MDPI, Basel, Switzerland.

Biological Sciences and Engineering

Fulltext

Antibodies

Therapeutic efficacy of anti-bestrophin antibodies against experimental filariasis: Immunological, immune-informatics and immune simulation investigations

Journal of Thrombosis and Haemostasis

Vaccine-induced immune thrombotic thrombocytopenia: Consider IVIG batch in the treatment

The ability to regulate the recruitment of immune cells makes chemokines and their receptors attractive drug targets in many inflammatory diseases. Based on its preferential expression on T helper type 2 (Th2) cells, C-C chemokine receptor type 4 (CCR4) has been widely studied in the context of allergic diseases, but recent evidence on the expression of CCR4 in other cell types has considerably expanded the potential applications of CCR4 antagonism. However, the current number of approved indications, as well as the portfolio of CCR4-targeting drugs, are still limited. In the present study, we have assessed the potential therapeutic efficacy of a CCR4 small molecule antagonist, SP50, discovered via an in silico-based approach, against a variety of pre-clinical settings of infection with the fungus Aspergillus fumigatus. We show that SP50 efficiently worked as prophy-lactic vaccine adjuvant in immunocompetent mice, protected against invasive aspergillosis in im-munosuppressed mice. Further, the CCR4 antagonist prevented allergic bronchopulmonary asper-gillosis in susceptible mice, and in a murine model of cystic fibrosis, a genetic disorder characterized by chronic pulmonary inflammation and recurrent infections. In conclusion, our results extend the potential applications of CCR4 antagonism and prompt for the development of novel compounds with the potential to progress to clinical trials. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.