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Brake friction composite materials comprising varying proportions of natural (banana) and inorganic (lapinus) fibers were designed, fabricated by compression molding, and characterized for sliding wear performance. The sliding wear properties of the manufactured friction composites have been studied by the Taguchi method. An orthogonal array (L 16) was used to investigate the influence of sliding wear parameters. A series of tests were conducted on a pin-on-disc machine by considering four control parameters: composition, normal load, sliding velocity, and sliding distance, each having four levels. The results showed that the wear in terms of weight loss decreases with increasing banana fiber and increases with increasing lapinus fiber, normal load, sliding velocity, and sliding distance. The results indicate that the normal load emerges as the most significant control parameter affecting wear performance, followed by sliding distance and sliding velocity.

Human Activity Recognition (HAR) in videos using convolution neural network become the preferred choice for researcher due to the tremendous success of deep learning models for visual recognition applications. After the invention of the low-cost depth sensor, multiple modalities based activity recognition systems were successfully developed in the past decade. Although it is always challenging to recognize the complex human activities in videos. In this work, we proposed a deep bottleneck multimodal feature fusion (D-BMFF) framework that fused three different modalities of RGB, RGB-D(depth) and 3D coordinates information for activity classification. It helps to better recognize and make full use of information available simultaneously from a depth sensor. During the training process RGB and depth, frames are fed at regular intervals for an activity video while 3D coordinates are first converted into single RGB skeleton motion history image (RGB-SklMHI). We have extracted the features from multimodal data inputs using the latest deep pre-trained network architecture. The multimodal feature obtained from bottleneck layers before the top layer is fused by using multiset discriminant correlation analysis (M-DCA), which allows for robust visual action modeling. Finally, using a linear multiclass support vector machine (SVM) method, the fused features are categorized. The proposed approach is evaluated over four standard RGB-D datasets: UT-Kinect, CAD-60, Florence 3D and SBU Interaction. Our framework produces outstanding results and outperformed the state-of-the-art methods.

With each passing year, new research is being carried out to discover materials with enhanced load-bearing capacity for prostheses and medical equipment. This study deals with the fabrication and mechanical testing of nano-zirconium oxide (n-ZrO2; 0–15 wt.%; at steps of 5%) reinforced Al 6061 prepared via a stir casting process. The effect of n-ZrO2 loading on physical and mechanical properties along with the detailed characterization has been systematically investigated. The density (2.6491–2.6812 g/cc), hardness (85–103 HV), tensile strength (147–227 MPa), tensile modulus (75–99 GPa), flexural strength (312–450 MPa), and impact strength (23–45 J) improved by increasing the wt.% of n-ZrO2 reinforcement particles. Furthermore, representative quantity element-based computational homogenization modeling was used to evaluate physical and mechanical properties. It was found to be in good agreement with the experimental results within a deviation of ~ 5%. The implication of these findings shows that 5 wt.% nano-ZrO2 reinforced Al 6061 composites (Al-ZC1) yielded better performance than pure Al 6061 alloy. This novel and comprehensive similarity throughout the examined properties for intricate microstructures perhaps be beneficial for designing optimum composite structures for prosthetic and orthotic applications.

The present work revealed the suitability of white ark shell powder (WASP) in brake friction materials application by analyzing and comparing the tribo-performance of WASP composite specimen with cashew nut shell liquid (CNSL) powder specimen. The composite specimens were fabricated with 70 wt% of WASP/CNSL powder and 30 wt% of phenol formaldehyde resin using compression moulding. The tribo-tests were carried out on wear and friction monitoring test setup at 2.6, 5.2 and 7.8 m/s of sliding velocities under the normal loads of 50 and 150 N. The tribo-test results showed that WASP composite offered lower friction coefficient in the range of 0.17–0.27 and higher wear resistance than that of the CNSL composite specimen. The stability coefficient of WASP composite was found higher than the CNSL composite at most of the sliding conditions. Less noise and vibrations were observed during experimentation of WASP specimen as compared to the CNSL specimen. The water absorption percentage of WASP composite was found lower than the CNSL composite specimen. The morphology of WASP specimen was observed smoother and less damaged than the CNSL composite specimen as evident from the scanning electron microscopy (SEM). On the basis of tribo-performance, white ark shell powder may be suggested as a potential filler to stabilize the friction coefficient and reduce weight loss, noise and vibrations in brake friction materials application.

The aim of this present work was to study the applicability of waste marble dust (MD) in poly(lactic acid) (PLA)-based composites. Samples containing up to 20 wt% waste MD were prepared via melt blending. The attention was focused on the investigation of mechanical, morphological, thermal properties and the wear resistance of the PLA/MD composites. Regarding the mechanical properties, both the tensile and the flexural modulus improved remarkably, however, a slight loss was observed in strength and deformability. The impact toughness showed an increasing tendency up to 10 wt% MD loading, which was followed by a marginal decrease at higher concentration. With respect to the sliding wear rate, the composite with the highest MD content showed the best wear resistance. According to the DSC measurements, the MD hampered the chain mobility of PLA, thereby reducing the crystalline ratio. Overall, composites with improved properties were developed, while the reuse of waste MD is expected to reduce the production costs as well.

Bioceramics have been widely utilized for orthopaedic applications in which the biocompatibility and mechanical properties of the materials are vital characteristics to be considered for their clinical use. Till date, extensive studies have been devoted to developing a range of scientific ways for tailoring the microstructure of bioceramics in order to attain the trade-off of mechanical properties and biocompatibility of the final product. Owing to low reactivity, earlier stabilization and longer functional life of bioceramic, the developed implants are capable of replicating the mechanical behaviour of original bone. As the safety of the patient and its ultimate functionality are the ultimate goal of the selected implant material hence, the present literature survey investigates and brings forth the important aspects associated to the mechanical, biological and microstructural characteristics of bioceramics employed in orthopaedic applications. The review paper majorly focuses on effective utilization of various materials as an additive in bioceramics and processing techniques used for enhancement of properties, enabling the use of material in orthopaedic applications. The influence of various additives on the microstructure, mechanical properties and biological performance of developed bioceramics orthopaedic implants has been elaborately discussed. Furthermore, future prospects are proposed to promote further innovations in bioceramics research.

The aluminium matrix composite (AMCs) plays a significant role in enhancing the properties of the material that are applicable in automotive industries, marine, aerospace, etc. Whereas these AMCs were further researched with the integration of reinforcing particulates in different percentages with the aim of enhancing the characteristics of parent aluminium matrix. Introducing ceramic particulate reinforcements into aluminium matrix produces a composite with better physical, mechanical and tribological properties in comparison to the traditional engineering materials. The main purpose of producing aluminium matrix composites (AMCs) is to develop lightweight materials having high stiffness and high specific strength. There are different effects observed with subsequent addition of reinforcements on the aluminium matrix composite. This paper attempts to present a review concerning the mechanical and tribological characteristics of aluminium matrix composite synthesized via stir casting route. This literature review provides an insight to the effects encountered after incorporating hard Si3N4 particulates in aluminium matrix along with its performance. It also attempts to highlight the impact of addition of silicon nitride (Si3N4) in AMCs, as this ceramic possesses superior wear and mechanical characteristics. Moreover, the effect of different reinforcements upon minimizing the resultant friction as well as wear for attaining superior lubrication will also be discussed in detail.

The present investigation explores the effect of mechanical fastening of natural filler (orange peel) based epoxy composite on the tensile, flexural, and impact strength. Open mold casting technique used to fabricate composites with the orange peel of average size 500 µm as filler material and epoxy and as a matrix material. Four compositions of samples were fabricated, having 0, 5 and 10 wt% of orange peel in the composite. For the examination of joining strength, the composite samples were fastened with single and double nut and bolt. Results suggested that fastened composites samples exhibit slightly low tensile and flexural strength than parental composites but exhibit higher impact energy capability. Bearing and shearing strength was found to be higher, having higher filler content and fastened by double nut and bolts. Highest tensile (42.89 MPa) and flexural strength (48.86 MPa) were observed for O0 samples while O8 sample showed highest impact energy (2.5 J), shear (4.26 MPa) and bearing strength (21.18 MPa).

Present work aims to investigate the thermal conductivity and mechanical characterization of the textile material reinforced polymer composites. Low cost needle-punched nonwoven fabric mat were used as reinforcing material. Polymer composites were developed with various weight percentages of 400gsm and 600gsm fabric mats in epoxy matrix by hand lay-up technique. Mechanical characterization such as hardness, impact energy, flexural and strength were examined experimentally of the fabricated composites. Thermal conductivity of the fabricated composites was also evaluated experimentally and theoretically. Experimental results revels that the evaluated mechanical properties increases while the thermal conductivity decreases with increased fabric weight percentage.

In this work, the tribological performance of aramid-lapinus fiber combination reinforced phenolic-based automotive brake friction composites was investigated using a pin-on-disc machine. Wear in terms of weight loss and coefficient of friction were determined as a function of applied load (80, 120, 160, and 200 N), sliding velocity (1.67, 3.34, 5.01, and 6.68 m/s) at a fixed sliding distance of 4000 m. The experimental results revealed that with increased applied load, the wear of the composites was increase while the coefficient of friction was found to decrease. On the other hand, higher wear was recorded with increased sliding velocity, while the coefficient of friction decreased after attaining a peak at 5.01 m/s. The lower aramid fiber and higher lapinus fiber combination resulted in increased friction performance, while an excellent wear performance was recorded for the composites having lower lapinus and higher aramid fiber as reinforcement.

The total joint replacement operation is excellent progress in the field of orthopedic implants surgery. In this review, physical, mechanical, and wear behaviour of various hip implant composite materials for the hip joint replacement applications was presented. This is multidisciplinary research covering a broad scope of subjects, including biomaterials (particularly bio-ceramic materials) and their mechanical and wear response. Many researchers have shown their willingness in formulating and developing novel hip implant composites and study their biocompatibility under simulated body fluid environment. The hip implant materials are chosen on the grounds of two main criteria (i) to rejuvenate function and (ii) to acquire aesthetic characteristics. The other essential consideration comprises biocompatibility, physical properties, mechanical properties, tribological properties, reasonable cost and availability. This paper will hand over a review of the hip replacement technology, injectable biomaterials comprising its design requirement together with differentiation between physical and mechanical properties, and efficacy for each system. The sole intention of the this review is to yield the background knowledge on the issues and problems to be deliberated in this thesis and to highlight the importance of the present study.

Nowadays, the use of industrial, municipal and agricultural wastes in reinforced polymers has become a common practice in composite industry. This paper discusses the feasibility of adding lathe waste as reinforcement of polymer composite. The effects of the incorporation of two types of lathe waste (mild steel and aluminium alloy 6063; 10–40 wt%) on the physico-mechanical behavior of epoxy composites were experimentally studied. The finding indicates that higher content of waste steel and aluminium alloy content in the fabricated composite resulted in increased density, void content and hardness. The composites containing 30 and 20 wt% aluminium and steel waste content showed higher mechanical properties.

The growing need for sustainable technologies has attracted considerable interest in the synthesis of ecofriendly materials. This paper reports the anti-inflammatory and antibacterial activities of...

This work is motivated by the tremendous achievement of deep learning models for computer vision tasks, particularly for human activity recognition. It is gaining more attention due to the numerous applications in real life, for example smart surveillance system, human–computer interaction, sports action analysis, elderly healthcare, etc. Recent days, the acquisition and interface of multimodal data are straightforward due to the invention of low-cost depth devices. Several approaches have been developed based on RGB-D (depth) evidence at the cost of additional equipment’s setup and high complexity. Contrarily, the methods that utilize RGB frames provide inferior performance due to the absence of depth evidence and these approaches require to less hardware, simple and easy to generalize using only color cameras. In this work, a deeply coupled ConvNet for human activity recognition proposed that utilizes the RGB frames at the top layer with bi-directional long short-term memory (Bi-LSTM). At the bottom layer, the CNN model is trained with a single dynamic motion image. For the RGB frames, the CNN-Bi-LSTM model is trained end-to-end learning to refine the feature of the pre-trained CNN, while dynamic images stream is fine-tuned with the top layers of the pre-trained model to extract temporal information in videos. The features obtained from both the data streams are fused at decision level after the softmax layer with different late fusion techniques and achieved high accuracy with max fusion. The performance accuracy of the model is assessed using four standard single as well as multiple person activities RGB-D (depth) datasets. The highest classification accuracies achieved on human action datasets are compared with similar state of the art and found significantly higher margin such as 2% on SBU Interaction, 4% on MIVIA Action, 1% on MSR Action Pair, and 4% on MSR Daily Activity.

We have reported the development of a computer code based on Method of Characteristics (MOC) to solve neutron transport equation for mainly lattice (i.e. assembly) level calculations with reflective and periodic boundary conditions and to some extent, core level calculation with vacuum boundary condition. Performance of the code has also been demonstrated with flat and linear source assumptions. In a subsequent work, we have implemented Krylov subspace iteration method for accelerating the MOC solution and in that context, introduced the concept of a matrix-free approach for using the code in solving large problems in effective manner. The acceleration technique is then used in combination with both kind of source assumptions, mentioned above, to solve a number of benchmark problems and demonstrate the capability and validity of the code. In continuation of the study, few more benchmark problems are selected from the literature to verify the performance of the code and their results are reported in the present paper.

In nuclear reactor, a variety of ducts are equipped in the radiation shield. Beam tubes, used for experimental facilities for research and development are one of them. It is very important to estimate the neutron and gamma photon flux profile inside as well as at the exit of the duct. This is required from experimental as well as radiation protection point of view. One way to estimate these flux profiles is to use transport method and another way is to use semi-empirical formula which describes energy-space distributions of streamed neutrons and gamma photons in various beam tubes with different shapes. Deterministic transport methodology using discrete ordinates approximation cannot be accurately model the streaming problems. This is due to inability to incorporate sufficient number of angular mesh points in the direction of streaming paths, which leads to ray effect (Miller and Lewis in Computational methods of neutron transport, Wiley, New York, 1985). This ray effect arises in the problem (radiation shielding etc.) having very little scattering and localized sources. In such problems anomalies (unphysical oscillations in the computed scalar flux) likely to arise in the scalar flux distribution. As a result, considerable underestimation occurs. Monte Carlo transport methods seem to be the best method in dealing streaming problems. However, reliable results with small statistical errors are not necessarily obtained in reasonable computation time. So, the use of semi-empirical formula will give the result with suitable accuracy and in less time. In this paper, streaming of neutrons as well as gamma photons through the beam tubes has been calculated using semi-empirical formula and compared with Monte Carlo results. Here, we have considered cylindrical ducts and the results obtained by semi-empirical formula are comparable with those from Monte Carlo code. The results can be verified further when the neutron-gamma flux measurement is done.

A static, full core calculation for IAEA 10 MWth Material Test Reactor (MTR) benchmark problem is carried out using a standard set of computer code systems, namely: (i) WIMSD/4, TWOTRAN and NEMSQR and (ii) DRAGON and NEMSQR. The current work focuses on the evaluation of various important neutronic parameters such as neutron multiplication factor, reactivity feedback coefficients, reactivity worth of control devices, etc. of the IAEA 10 MWth MTR benchmark reactor, using the above code systems. The IAEA 10 MWth benchmark problem is useful for testing the ability of a code to reliably simulate a compact, highly heterogeneous core made up of U235-enriched fuel in plate-type geometry. The study is carried out to validate the calculation methodology currently adopted by us for plate-type fuel assemblies and compact reactor cores while using these standard computer codes.

It is widely recognized that simulators play an essential and extremely important role in training programs for nuclear power plants (NPPs). The full-scope training simulators provide such in-depth training tools for reactor operators. A full-scope simulator has been developed for research reactor, Dhruva at BARC. The details about the development activities are covered in this paper. Safety analysis and operational experience consistently indicate that human error is one of the key contributors to the risk of a severe accident in a nuclear reactor. The use of full-scope simulator in the training of operators is an essential element to reduce human error. This paper presents the core neutronics and thermal hydraulics of model of Dhruva reactor incorporated in the Dhruva simulator. The core neutronics module is based on point kinetics model which estimates the reactor power depending on the core reactivity. The simulator can reproduce the different operational scenario, i.e., reactor operation under equilibrium and non-equilibrium condition, xenon transients, loss of regulation incidents, etc. The simulator will also be used to study the role of human reliability in safety of nuclear plants. The simulator was so designed that over and above training of the plant personnel, it will be used for safety studies in the area of reactor physics and thermal hydraulics. The interface was designed to support the interaction of the operators with the simulator through virtual panels supported by touch screens with high-fidelity graphic displays. Important Postulated Initiating Events (PIEs) like Loss of Offsite Power, Loss of Coolant Accident, Loss of Regulation Incident, etc. have been modeled. This information will provide an insight to verify and validate the plant Emergency Operating Procedures (EOPs). The simulator will also be used for development of human factor models as well as the design of future Visual Display Unit based control rooms. This will also enable the operators to align themselves from the traditional panel-based Human–Machine Interface to personal computers.

Neutron transport codes are an integral part of reactor physics calculation. The freely available lattice code DRAGON results from an effort to unify inside a single computer code various well-established numerical techniques and calculation methodologies which are commonly used to solve the neutron transport equation. It is of utmost importance for the user community, both from safety and operation point of view, that the codes being utilised for neutronic calculations maintain a high degree of confidence in their predictions. Benchmark problems are designed to test the capability of a neutronic code by comparing the results obtained from the code with well-established results, either from experimentation or from other validated neutronic codes. After PWRs, BWRs, and PHWRs are two of the most popular types of nuclear reactors currently in use worldwide. Consequently, the ability to perform accurate neutronic calculation involving these lattice types can be deemed as a necessary requirement in most modern lattice codes. In this work, we will study two benchmark problems based on the aforementioned reactor lattice types. Using the lattice code DRAGON and subsequently comparing the results with available published solutions, we aim to ascertain the capability of DRAGON to effectively simulate both of these two types of lattices with fresh and burnt fuel.

Supplemental material, sj-doc-1-smo-10.1177_20503121221074785 for Clinical and histology features as predictor of severity of mucormycosis in post-COVID-19 patients: An experience from a rural tertiary setting in Central India by Kavita Jain, Akshay Surana, Tej Singh Choudhary, Sudhakar Vaidya, Shirish Nandedkar and Manju Purohit in SAGE Open Medicine

This work represents the comparative behaviour of the mechanical characterization of polymer composites reinforced with natural fibers. Therefore, epoxy composites containing varying amount of natural fibers (5 wt%, 10 wt%, 15 wt% and 20 wt%; bagasse and jute) were prepared and characterized for their mechanical properties. Experimental results indicated that inclusion of increased fibrous loading improves the evaluated mechanical (impact energy, hardness, flexural and tensile strength) properties of the manufactured composites. Comparatively to bagasse fiber reinforced composites it was found that the evaluated mechanical properties were remained higher for jute fiber reinforced composites. It was also observed that tensile and flexural properties are between 15 and 40 MPa and impact energy of the composites between 2 and 3 J.

Introduction:Anemia of chronic disease is defined as anemia occurring in chronic infections, inflammatory conditions or neoplastic disorders that are not due to marrow deficiencies or other diseases, and occurring despite presence of adequate iron stores and vitamins. Methods: A total of 40 patients were selected for the study. Participants were divided into two groups viz group A (test group; n=20) with moderate to severe periodontitis and group B (control group; n=20) with periodontally healthy subjects. The patients chosen for the study had at least 30% or more of teeth having greater than or equal to 4 mm probing depth. Clinical parameters like gingival index (GI), Sulcus Bleeding Index (SBI), plaque index (PI),probing pocket depth (PD) and clinical attachment levels (CAL) were recorded for all the patients and blood parameters (hemoglobin and red blood cell count) were determined from peripheralblood samples. The results were analyzed statistically. Results: The mean values of hemoglobin (Hb) and red blood cell (RBC) count were significantly reduced in test group as compared to control group. Conclusion: A positive relationship was observed between the blood parameters viz. Hb, RBC count, and the severity of the chronic periodontal disease. Like other chronic conditions, periodontitis can tend towards anemia showing their association. Keywords: Anemia, Chronic Periodontitis, Hemoglobin (Hb), Red Blood Cell Count (RBC Count).