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The paper aims to add a novel dimension to the ongoing discourses on the erosion of indigenous knowledge. The loss of indigenous knowledge as a result of external forces (of modernization, market economy, development, and globalization) has been well documented. There is, however, a lack of understanding about the internal constraints or cultural factors, which may be as important as external (outside) factors in the erosion of knowledge. Extending the focus to internal cultural factors for effective knowledge management is also imperative. Therefore, the present study will examine this issue from a different perspective and with specific reference to the ethnomedicinal knowledge among a tribal society (the Konda Reddis) in South India. The paper discusses how internal constraints– such as social restraints of supernatural forces, and disruptions in knowledge transmission – are playing a critical part in the erosion of indigenous medicinal knowledge.

A miniature Multiple Input Multiple Output (MIMO) Ultrawideband (UWB) antenna with C-band notch is recommended for wireless communications. The radiator is etched on an economical FR4 substrate and is 40 × 21 mm2in size. The antenna is comprised of a circularly notched rectangular patch embedded with an ellipse and is fed by a 50-Ω microstrip line. To reduce mutual coupling by < −18 dB throughout the whole operational bandwidth of 2.94–11.61 GHz without employing any coupling device, the two radiators are positioned side-by-side with a separation of 0.03 λ0(λ0is the wavelength at the lower cutoff frequency of 2.94 GHz). A U-type slit is cut into the patch to produce the band-notch at C-band across 3.63–4.15 GHz. Results from simulation and experiment concludes that the suggested radiator has a wide impedance bandwidth (S11< – 10 dB) and strong mutual coupling (S21 < −18 dB) between 2.94 and 11.61 GHz. Except at the notch frequency of 4 GHz, where the gain is −3.21 dBi, the peak gain and peak radiation efficiency are both 4.21 dBi and more than 82%, respectively. The measured envelope correlation coefficient (ECC) of 0.002, peak diversity gain (DG) of 9.999 dB, and mean effective gain (MEG) of less than −3 dB over operating band, along with the omnidirectional characteristics of the radiator, prove its suitability for use in wireless systems.

ABSTRACTSurveillance of underwater for maritime warfare is traditionally being carried out by bearings-only tracking from many decades. The measurements used for state estimation here are nonlinear. Also the noise in the measurements and the process cannot be always Gaussian. The traditional nonlinear filtering algorithms like extended Kalman filter and modified gain extended Kalman filter use the linearisation of the system. The unscented Kalman filter (UKF) uses the sigma point approach based on Gaussian distribution to deal with nonlinearity. The particle filter (PF) uses the randomly generated particles based on the pdf of the state. PF is highly complex to implement and it also suffers from sample impoverishment. Hence, ensemble Kalman filter (EnKF) which is a simplified form of PF will be tried out for bearings-only tracking in this research work. The performance of EnKF is compared with PF and UKF and the results obtained using these filters in Matlab are presented.

This work presents the controlling of the pitch orientation of a twin-rotor multi-input multi-output system (TRMS) using the sliding mode control (SMC) technique with variable gains. In this, the SMC is designed using variable gains where the pitch orientation error of the vertical dynamics of the TRMS system is intended to render the control law. The magnitude of the variable gains is related to the absolute value of the tracking error. Further, this technique minimised the chattering effect by ensuring the robustness property of the sliding modes. This design establishes a relationship between first and higher-order SMCs. The proposed controller is adapted from the twisting algorithm (TA) and conventional SMC. The control algorithm does not overestimate disturbances, resulting in a large reduction in control energy. Finally, a Lyapunov stability analysis is devised to demonstrate asymptotic stability. Simulations demonstrate the pitch orientation control and robustness of the proposed control scheme.

The issue of real-time state estimation in passive target tracking using only bearing measurements is addressed in this research. An algorithm has been developed to detect multiple targets and fuse state vectors when a single target is detected. Target detection is carried out considering the state vectors from two different sensor arrays with various noise variances. The algorithm is evaluated against targets having unique and identical parameters such as range, speed and course. The state vectors are determined using three different filtering techniques, namely, extended Kalman filter (EKF), modified gain bearings-only EKF and unscented Kalman filter. Using the MATLAB software environment, Monte-Carlo simulations are conducted to more precisely assess algorithm performance.

A compact and novel semi-elliptical defected ground structure (SE-DGS) tapered microstrip line fed UWB antenna with band-notched characteristics integrated with Ku and K band applications is proposed. The proposed SE-DGS UWB antenna is printed on a compact size of (15 × 18 mm2) and has radiation bandwidth of 25.66 GHz over a span of 4.11–29.77 GHz, a fractional bandwidth of 151.47%, and both the down link of X- and ITU-8 bands are completely notched over a span of 6.86–9.09 GHz using a single C-structured reflector. The proposed antenna has a fluctuating gain of 1.7–4.82 dBi except for the gain at the notched band frequency, which is −12.25 dBi. The proposed antenna has a high radiation efficiency of 96.23%, stable radiation patterns over the UWB range, and a high rejection capability of the notched band, which is noticed from the high value of VSWR of 23.15, making it a potential candidate for UWB, Ku, and K band wireless applications with effectively suppressed downlink of X and ITU-8 bands. The developed antenna design simulates breast cancer tissue detection by comparing S21results, and specific absorption rates with and without tumour scenarios. These results suggest that the proposed radiator and system detect breast tumours efficiently.

Background: A filamentous fungus Penicillium rubensis widely recognized for producing industrially important antibiotic, penicillin at industrial scale. Objective: To better comprehend, the genetic blueprint of the wild-type P. rubenswas isolated from India to identify the genetic/biosynthetic pathways for phenoxymethylpenicillin (penicillin V, PenV) and other secondary metabolites. Method: Genomic DNA (gDNA) was isolated, and library was prepared as per Illumina platform. Whole genome sequencing (WGS) was performed according to Illumina NovoSeq platform. Further, SOAPdenovo was used to assemble the short reads validated by Bowtie-2 and SAMtools packages. Glimmer and GeneMark were used to dig out total genes in genome. Functional annotation of predicted proteins was performed by NCBI non-redundant (NR), UniProt, Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Ontology (GO) databases. Moreover, secretome analysis was performed by SignalP 4.1 and TargetP v1.1 and carbohydrate-active enzymes (CAZymes) and protease families by CAZy database. Comparative genome analysis was performed by Mauve 2.4.0. software to find genomic correlation between P. rubensBIONCL P45 and Penicillium chrysogenumWisconsin 54–1255; also phylogeny was prepared with known penicillin producing strains by ParSNP tool. Results: Penicillium rubensBIONCL P45 strain was isolated from India and is producing excess PenV. The 31.09 Mb genome was assembled with 95.6% coverage of the reference genome P. chrysogenumWis 54–1255 with 10687 protein coding genes, 3502 genes had homologs in NR, UniProt, KEGG, and GO databases. Additionally, 358 CAZymes and 911 transporter coding genes were found in genome. Genome contains complete pathways for penicillin, homogentisate pathway of phenyl acetic acid (PAA) catabolism, Andrastin A, Sorbicillin, Roquefortine C, and Meleagrin. Comparative genome analysis of BIONCL P45 and Wis 54–1255 revealed 99.89% coverage with 2952 common KEGG orthologous protein-coding genes. Phylogenetic analysis revealed that BIONCL P45 was clustered with Fleming’s original isolate P. rubensIMI 15378. Conclusion: This genome can be a helpful resource for further research in developing fermentation processes and strain engineering approaches for high titer penicillin production.

Super duplex stainless steel (SDSS) plates of 6 mm thickness have been welded using tungsten inert gas, activated tungsten inert gas, electron beam welding and friction stir welding processes. Among these, in the first two, melting and solidification of material occurs slowly whereas, it is faster in electron beam welding process and no melting occurs in friction stir welding. Macro and microstructural studies, hardness surveys, tensile tests and percentage of ferrite content were compared for all the welds. The ferrite–austenite phase balance is 50 % each, with electron beam weld metal at about 65 % ferrite. This showed the hardness of the weld metal and heat affected zones to be higher than base metal. The weldment joint efficiencies are more than 90 %. The fracture location is found to be in the weld metal for tungsten inert gas and activated tungsten inert gas weld, in the nugget for friction stir welds and in the base metal for electron beam welds. The ductility of electron beam weld joints is 32 % while it is around 20 % for the others. The preferred order while choosing the welding process should be activated tungsten inert gas welding, tungsten inert gas welding, electron beam welding, and friction stir welding.

Graphical Abstract:

In this study, high velocity impact behaviour of friction stir welded AA7075-T651 25 mm thick plates were investigated using a 7.62 mm × 51 mm lead core and 7.62 mm × 39 mm steel core projectiles. Prior to ballistic trails, mechanical and metallurgical properties of friction stir welded AA 7075-T651 25 mm thick plates were studied. Microstructural and hardness studies revealed that friction stir welds constituted three distinct regions namely Weld Nugget (WN), Thermo-Mechanically Affected Zone (TMAZ) and Heat Affected Zone (HAZ). Base Material (BM) and all three weld regions were ballistically tested as per military standard NIJ.0108.01 using lead and steel core bullets at maximum permissible velocities of 830 ± 20 and 700 ± 30 m/s, respectively. It has been found that base material (AA7075-T651) and all three weld regions of 25 mm thick plates were able to resist perforation by both types of projectiles used. However depth of penetration has been found to increase from BM to WN, HAZ and TMAZ for both types of projectiles. In all cases steel core projectiles caused higher depth of penetration compared to those caused by lead core projectiles. TMAZs of the friction stir welds were found to be the weakest zone. The fracture that occurred in the base material was spall fragmentation indicating brittle failure, whereas all zones of friction stir welded AA7075-T651 targets with a front petalling, indicating ductile failure. The post-ballistic tested samples showed no significant change in the microstructure of the BM and WN. On the other hand, TMAZ and HAZ showed severe grain deformation in the direction of projectile penetration, and the formation of adiabatic shear bands (ASB). This work showed that 25 mm thick friction stir welded AA7075-T651 joints responded well to ballistic impact loads, making them a good choice for light combat vehicles.

As macroscopic Breast Cancer (BC) imaging diagnostics do not provide satisfied data, microscopic image analysis is used to get optimum cell-nuclei segmentation for image categorization. The paper presents a Novel Hybrid Segmentation Method which uses the energy detail coefficients attained from Non-Subsampled Contourlet Transform for cell-nuclei segmentation of BC histopathological images. NHSM solves the local inhomogeneities problem while preserving all necessary details. The system evaluation is done using training dataset of 98 BC histopathological images and testing dataset of 26 images. Total of 25 segmented features was extracted for classification using Decision Trees, k-Nearest Neighbor, multilayer perceptron, Multiclass-Support Vector Machine (M-SVM). The proposed NHSM segmentation results were undergone through both subjective and objective performance evaluation. Result evaluation proved that NHSM along with Multi Class-Support Vector Machine classifier provides highly precise and accurate classified result for BC tissue images compared to state-of-the-art segmentation methods. Also, the edge detection model initialization is highly robust and insensitive.

In passive target tracking, target motion parameters (TMP) i.e.range, course, and speed are estimated using bearing measurements. In the simulation mode, the accuracy of the estimated solution can be calculated, as true values are available. In the actual scenario, the true values of TMP are not readily obtainable. In this research, the focus is laid on the evolution of the acceptance criterion of the TMP in the actual scenario. Detailed mathematical modeling is carried out and an unscented Kalman filter (UKF) is used to estimate TMP. The state vector covariance matrix of UKF is utilized to express the errors in estimated TMP and an acceptance criterion is derived in terms of the standard deviation of errors in estimated TMP. Submarine to submarine tracking is carried out and scenarios are chosen accordingly. Several low angle on target bow (ATB) scenarios are used in the Monte-Carlo simulation and the results are presented. A similar procedure can be carried out for medium and high ATB scenarios and a submarine to ship or vice-versa passive target tracking.