Polar codes are the popular error-correcting codes and increased their attention after being adopted for the control channel in fifth-generation new radio (5G NR) standards. An efficient hardware architecture for polar code is often required with minimal encoding and decoding complexity. This work proposes a Multi-folded pipelined architecture and analyzes the performance in terms of latency, hardware utilization, and throughput. The designed architecture has two folded architectures interconnected in parallel to output 4-bits simultaneously. Folding transformations are used to reduce the number of idle processing elements (PEs) in every stage leading to the effective utilization of PE. Precomputation is effectively utilized in the PE to reduce the critical path delay, which improves the maximum operating frequency. A Loop-based shifting register (LSR) is employed to reduce the number of registers used. The analytical model for latency and utilization rate has been derived from the scheduling of the proposed architecture. The proposed design shows 63–71 N=512 suitable for the physical downlink control channel (PDCCH) in 5G NR. The architecture is also implemented in Virtex-6, ZYNQ-Ultrascale+ MPSoC device for maximum supported code length of 5G NR, i.e., up to 2^10 , compared with the existing decoders. The proposed design also has the benefit of lesser look-up-table (LUT) consumption and zero random-access-memory (RAM) usage with some additional registers, making it suitable for resource-constraint applications.

The development of advanced thermal barrier coating (TBC) materials with better hot corrosion resistance, phase stability, and residual stresses is an emerging research area in the aerospace industry. In the present study, four kinds of TBCs, namely, single-layer yttria-stabilized zirconia (YSZ), single-layer gadolinium zirconate (GZ), bilayer gadolinium zirconate/yttria-stabilized zirconia (YSZ/GZ), and a multilayer functionally graded coating (FGC) of YSZ and GZ, were deposited on NiCrAlY bond-coated nickel-based superalloy (Inconel 718) substrates using the atmospheric plasma spray technique. The hot corrosion behavior of the coatings was tested by applying a mixture of Na2SO4 and V2O5 onto the surface of TBC, followed by isothermal heat treatment at 1273 K for 50 h. The characterization of the corroded samples was performed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) to identify physical and chemical changes in the coatings. GIXRD was used to analyze the residual stresses of the coatings. Residual stress in the FGC coating was found to be −15.2 ± 10.6 MPa. The wear resistance of TBCs is studied using a linear reciprocating tribometer, and the results indicate that gadolinium zirconate-based TBCs showed better performance when deposited in bilayer and multilayered functionally graded TBC systems. The wear rate of as-coated FGC coatings was determined to be 2.90 × 10−4 mm3/Nm, which is lower than the conventional YSZ coating.

Friction reduction of AlTiN-based hard coatings is gaining much attention among researchers worldwide to broaden their tribological applications. Metal/non-metal inclusions, as well as the design of a novel coating architecture, are primarily focused on reducing friction while retaining wear resistance. This study investigates the tribological characteristics of magnetron sputtered AlTiN coatings by incorporating amorphous carbon (a-C) at different concentrations (5-25 at.%), as well as the compositionally graded AlTiN/a-C coatings (CGC). The XPS and Raman spectroscopy results confirm the presence of a-C features, while XRD reveals the formation of ceramic carbide phases in AlTiN coatings with higher carbon content and CGC coatings. The CGC AlTiN/a-C have shown a maximum hardness of 34.3 GPa and an elastic modulus of 321 GPa due to their refined grain structure. The CGC had the lowest friction (0.18 at 300 K and 0.37 at 673 K), as well as improved wear resistance (2.74 x 10(-7) mm(3)/Nm (300 K) and 4.93 x 10(-7) mm3/Nm (673 K)). The tribolayers are found to be mainly composed of sp(2)/sp(3) bonded a-C features (including C=C/C & horbar;C, C & horbar;N, and C & horbar;O), which reduces the friction force significantly. The CGC AlTiN/a-C coating has exhibited improved wear resistance behavior due to their finely grained structure and improved mechanical properties.

Diamond-like carbon (DLC) coatings doped with bioactive elements of silver (Ag) and copper (Cu) have been receiving increasing attention in the last decade, particularly in the last 5 years, due to their potential to offer a combination of enhanced antimicrobial and mechanical performance. These multi-functional bioactive DLC coatings offer great potential to impart the next generation of load-bearing medical implants with improved wear resistance and strong potency against microbial infections. This review begins with an overview of the status and issues with current total joint implant materials and the state-of-the art in DLC coatings and their application to medical implants. A detailed discussion of re-cent advances in wear resistant bioactive DLC coatings is then presented with a focus on doping the DLC matrix with controlled quantities of Ag and Cu elements. It is shown that both Ag and Cu doping can im-part strong antimicrobial potency against a range of Gram-positive and Gram-negative bacteria, but this is always accompanied so far by a reduction in mechanical performance of the DLC coating matrix. The article concludes with discussion of potential synthesis methods to accurately control bioactive element doping without jeopardising mechanical properties and gives an outlook to the potential long-term im-pact of developing a superior multifunctional bioactive DLC coating on implant device performance and patient health and wellbeing. Statement of significance Multi-functional diamond-like carbon (DLC) coatings doped with bioactive elements of silver (Ag) and copper (Cu) offer great potential to impart the next generation of load-bearing medical implants with improved wear resistance and strong potency against microbial infections. This article provides a criti-cal review of the state-of-the-art in Ag and Cu doped DLC coatings, beginning with an overview of the current applications of DLC coatings in implant technology followed by a detailed discussion of Ag/Cu doped DLC coatings with particular focus on the relationship between their mechanical and antimicrobial performance. Finally, it ends with a discussion on the potential long-term impact of developing a truly multifunctional ultra-hard wearing bioactive DLC coating to extend the lifetime of total joint implants. & COPY; 2023 The Author(s). Published by Elsevier Ltd on behalf of Acta Materialia Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )

Researchers are mainly concerned with minimizing friction and preventing the wear of moving mechanical components, since these problems create significant energy and economic constraints for many small-scale and large-scale mechanical industries. Nanomaterials, especially 2D nanostructures such as graphene and its derivatives graphene oxide or reduced graphene oxide (GO/rGO), and hexagonal boron nitride (h-BN), as additives in conventional lubricants attract significant attention because of the remarkable enhancement of anti-friction and anti-wear characteristics. This chapter aims to provide a detailed overview of recent developments in 2D nanomaterials dispersed in nanolubricants. The preparation of 2D nanomaterials, surface functionalization of graphene and h-BN using various chemicals/methods (oxidation, amine functionalization, alkylation, ionic liquids, and surface modifiers) and other nanoparticles, and their influences on the friction and wear behavior in nanolubricants are discussed in this chapter. Additive concentrations and their dispersion stability in lubricants, functional groups, and sliding conditions are the key determinants of the tribological properties of nanolubricants. The tribofilm formation mechanism and the impact of tribofilms on the anti-friction and anti-wear behavior of nanolubricants are also discussed in this chapter.

Hard and wear-resistant coatings created utilizing physical vapor deposition (PVD) techniques are extensively used in extreme tribological applications. The friction and wear behavior of coatings vary significantly with temperature, indicating that advanced coating concepts are essential for prolonged load-bearing applications. Many coating concepts have recently been explored in this area, including multicomponent, multilayer, gradient coatings; high entropy alloy (HEA) nitride; and functionally modified coatings. In this review, we highlighted the most significant findings from ongoing research to comprehend crucial coating properties and design aspects. To obtain enhanced tribological properties, the microstructure, composition, residual stress, hardness, and HT oxidation resistance are tuned through doping or addition of appropriate materials at an optimized level into the primary coatings. Such improvements are achieved by optimizing PVD process parameters such as input power, partial pressure, reactive gas flow rates, substrate bias, and temperature. The incorporation of ideal amounts of Si, Cr, Mo, W, Ag, and Cu into ternary and quaternary coatings, as well as unique multilayer designs, considerably increases the tribological performance of the coatings. Recent discoveries show that not only mechanical hardness and fracture toughness govern wear resistance, but also that oxidation at HT plays a significant role in the lubrication or wear failure of coatings. The tribo-induced metal oxides and/or Magnéli phases concentrated in the tribolayer are the key governing factors of friction and wear behavior at high temperatures. This review includes detailed insights into the advancements in wear resistance as well as various failure mechanisms associated with temperature changes.

A low-density parity-check code (LDPC) is one of the classical error-correcting code for message transmission over noisy channel. It meets desired Shannon limit performance and is adopted as a data channel for the 5th generation new radio (5G NR) standard. This paper investigates the LDPC decoder by applying minimum-sum (MS) algorithm on the base matrix (BG1) of 5G standards. The performance of the decoder such as bit-error-rate (BER) and frame-error-rate (FER) has been improved when the number of iterations increased for larger code word. The variable node and check node architecture based on the MS algorithm with pipelining stage has been implemented in the field programmable gate array (FPGA). Based on the implementation results, it is observed that the LDPC decoder shows better performance in throughput and hardware resource usage (HUE) with some additional look-up-tables (LUT) and flip-flops (FF).

Ceramic diffusion barrier coatings are inevitable in high temperature aerospace and nuclear applications to protect superalloys from oxidation and hot corrosion. Compositionally graded coating (CGC) of Ni-YSZ with five layers was deposited on an Inconel-690 substrate through electron beam physical vapor deposition (EBPVD) method. After heat treatment, the phase formation and crystallite determination in each layer of the CGC were studied by X-ray diffraction. Pulsed radio frequency glow discharge optical emission spectroscopy (RF-GDOES) showed outward diffusion of Ni towards the surface of the CGC. High resolution transmission electron microscopy (HRTEM) studies of the cross-sectional region of the heat-treated coating at 1273 K revealed no secondary phases within the coating as well as at substrate-coating interface. The corrosion behavior of Ni-YSZ coating under 3 M HNO3 medium showed that the heat-treated CGC of Ni-YSZ exhibited better corrosion resistance due to the formation of NiO than as-deposited Ni-YSZ coating.

Artificial implants have gaining interest to repair or replace the defect parts in the human system. Majorly, orthodontic and orthopedic implant materials are playing predominant role in replacing teeth with endosseous parts in oral as well as orthopedic applications such as endossceous implants, fracture fixation, total joint arthroplasty, and ankle fracture replacement. For this, several metallic materials, namely, stainless steel, titanium and its alloy, Ni-Cr, Co-Cr, and Mg-based alloy, have been commercially used. Other non-metallic materials such as ceramics, polymers, and metallic glasses have also explored in implant fixation to improve performance and durability of implants. Among various materials classifications in biomedical industries, implants used for load bearing applications (femoral heads, knee implant, and ankle prosthesis) have shown significant attention due to dynamic load and more possibilities, and wear debris formation hinders the potential implant functioning. The improvement of surface properties and load bearing ability of implants are mainly related to surface topography, roughness, and its stability in hostile environment. Surface coatings with smooth surface provide better functionality in articulating surfaces, and its surface texture improves the tribological properties which became more popular in biomedical field for the past few decades. In this chapter, recent advancements in development of bioactive coatings and its role in wear-resistant ism for various articulating surfaces (hip, knee, ankle, and spinal implants) will be discussed by describing root cause of short span of artificial joints using metallic implants. Furthermore, corrosion resistance and biocompatibility of surface modified materials are also discussed in detail.

Polar codes are the recently adopted error correction codes in the 5th generation new radio (5G NR) mobile communication standards. The hardware architecture for encoding and decoding plays a significant role in achieving channel capacity. The processing complexity due to successive cancellation (SC) algorithm is one of the limitations faced in the prior decoder architectures. In this study, semi-parallel architecture is employed which reduces the processing complexity. However, the partial-sum generation module in the conventional semi-parallel decoder occupies a larger space which in turn limits the operating frequency as code length N increases. A modified partial-sum computation model based on shift register (SR-PSU) is employed to improve the area utilization and maximum operating frequency. The SR-semi-parallel decoder is synthesized and implemented in a field-programmable gate array (FPGA) for code length up to N = 210. The proposed decoder shows a significant reduction in the critical path delay and processing complexity as compared to the conventional semi-parallel decoder. Copyright (c) 2022 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Conference on Innovative Technology for Sustainable Development.

The ongoing industrial revolution demands advanced tribological coatings for enhancing the performance of mechanical components by minimizing friction and wear-related losses. Recently, carbon-based coatings have been widely studied for many tribology applications. The functionality of the carbon-based coatings can be achieved by controlled modification of sp 2 /sp 3 hybridization ratio or hydrogen content during the deposition process. Amorphous carbon (a-C) coatings and hydrogenated a-C (a-C:H) or diamond-like carbon (DLC) coatings provide ultralow friction behavior due to the enrichment of sp 2 hybridized carbon features. Similarly, hydrogen-free carbon coatings with tetrahedral sp 3 bonded networks (70%) show higher wear resistance behavior. Crystalline diamond coatings with enriched sp 3 hybridized carbon features like microcrystalline diamond (MCD) and ultra/nanocrystalline diamond (U/NCD) coatings exhibit superhardness (50–100 GPa) and remarkable wear resistance behavior. Though these coatings provide superior tribo-mechanical properties at low-temperature (<100°C), tribological properties, however, rapidly deteriorate at elevated temperatures which limit their applications in different operating conditions. To overcome these limitations, researchers have developed duplex structures of suitable metallic and/or ceramic materials doped/embedded in an a-C matrix. This chapter reviews the recent innovations that have reported on all the aspects of carbon-based coatings.

This chapter describes the microstructural characterization of coatings prepared through physical vapor deposition (PVD) route. Coatings prepared through PVD are extensively used to enhance the tribological performance of forming tools, cutting tools, and machine components. In such applications, the microstructure of coatings are the most important factors widely used to evaluate the product and materials property. Recently, considerable attention has given to focus on the microstructure at the micro/nano level to clarify and to study the influence of microstructure in tribological performance of the coating. The primary characterization techniques used for the microstructural analysis of the coatings are X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS), atomic force microscopy (AFM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). These techniques are particularly useful in assisting the development of novel coatings by studying their microstructure at different scales.

Nuclear vitrification furnace made of Inconel-690 alloy fails prematurely due to alloy-borosilicate glass interaction by forming Cr rich secondary precipitates which results in the loss of corrosion resistance and incorporation of nuclear waste in the alloy-borosilicate interface. In this work, the development of a novel compositionally graded Ni-YSZ diffusion barrier coating using electron beam physical vapor deposition method was investigated to mitigate the issues related to inter-diffusion and elemental exchange across the alloyborosilicate melt without the addition of any nuclear waste. A comparative study on the interdiffusion effects of compositionally graded Ni-YSZ nanocomposite coating with increasing Ni content from 5 to 50 wt % subjected to diffusion annealing with and without borosilicate melt at 1373 K in air was carried out. No phase transformation was observed in Ni-YSZ coating subjected to diffusion annealing at 1373 K in air as observed from XRD analysis. FESEM-EDS analysis confirms the formation of NiO and grain growth of NiO in YSZ matrix after heat treatment. Raman spectroscopic studies confirmed the outward diffusion of Ni from the adjacent Ni rich multilayer to YSZ top coat and the formation of NiO at the surface of the Ni-YSZ nanocomposite. In contrast, there was no elemental exchange across the interface between nanocomposite coating and adhered borosilicate layer as there was no traces of NiO on the surface of the glassy layer. The wear behaviour was studied on the compositionally graded Ni-YSZ nanocomposite coatings subjected to high temperature diffusion annealing with and without borosilicate glass using a linear reciprocating tribometer by analyzing different modes of wear scar and the chemical changes inside the wear track using Raman spectroscopy. The observation of higher hardness and wear resistance obtained for the diffusion annealed Ni-YSZ nanocomposite was found to be due to the formation of NiO on the surface of the coating.

Physical vapor deposition (PVD) technologies are widely used to produce wear and corrosion resistant coatings for a variety of industrial applications. In recent years, there has been remarkable interest in the development of novel wear resistant coatings prepared through PVD methods, which helps to reduce friction and wear, as a result of recovering energy losses up to 30% due to friction and economy loss due to wear. This chapter provides comprehensive data of recent progress in wear resistant coatings prepared using PVD methods, starting with the introduction of it needs, significance, physiochemical properties, and the selection criteria of wear resistant coatings. The applications, physical, and chemical properties of superhard materials such as diamond like carbon (DLC), titanium nitride (TiN), chromium nitride (CrN), and tantalum nitride (TaN) are also presented.

In the aviation industry, there is a need to detect even the smallest damage in order to avoid a fatal accident. Aerospace structures undergo various kinds of damages due to the impact force of objects during flight. In particular, the forward- facing components like a wing leading edge are subjected to impact forces caused by natural incidents like bird strikes. This work investigates the damage detection on the wing's leading edge when hit by a bird during flight. The damage detection method proposed in this work uses Chirped Fiber Bragg Grating (CFBG) as a sensing element, whose reflection spectrum is analyzed to verify the presence of damage. The already existing methods make use of the Fiber Bragg Grating (FBG) sensor which has lesser impact than the CFBG sensor. The aircraft wing has been designed in SOLIDWORKS and strain simulation is carried out using COMSOL software. The parameters such as stress, strain and wave length shift are obtained which can be used for damage detection in aircraft structures.

Minimizing friction and wear is one of the continuing challenges in many mechanical industries. Recent research efforts have been focused on accelerating the antifriction and antiwear properties of hard coatings through the incorporation of self-lubricant materials or the development of new architectures. In this present study, carbon-rich MoC, MoCN, and multilayer MoC/MoCN coatings were deposited using reactive magnetron sputtering. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy were used to evaluate their properties, which revealed the presence of ceramic cubic crystallites, covalent bonds between primary elements, and an excess of amorphous carbon (a-C) in all of the coatings. The multilayer architecture and possible segregation of a-C around the ceramic crystallites resulted in improved mechanical properties for all coatings, with MoC/MoCN coatings having a maximum hardness of 21 GPa and elastic modulus of 236 GPa. Friction and wear behavior are initially determined by the structural-composition-property relationships of the respective coatings; later, the tribological characteristics are altered depending on the nature of tribolayer on both mating surfaces at the contact interface. The highest wear resistance of multilayer MoC/MoCN coating (8.7 × 10-8 mm3/N m) and MoC coating (3.9 × 10-7 mm3/N m) was due to the dissipation of contact stress by the tribofilm consisting of carbon tribo products like graphitic sp2 carbon, diamond-like sp3 carbon, and pyrrolic-N. On the other hand, MoCN coating depicted a lower wear resistance due to the frequent termination of C-H bonds by N, which restricts the strong formation of tribofilms as well as poor mechanical properties.

Today’s need for workers in mines is to detect the metals in the path. The previously used metal detector uses BFO (Beat Frequency Oscillation) and RFO (Resonant Frequency Oscillation) techniques which has a drawback of frequency instability. The depth further can be increased by Pulse Induction Method. It uses a single coil as both transmitter and receiver. When current is sent through the coil each pulse generates a magnetic field. When the pulse ends it reflects and it is called the reflected pulse. An electrical spark is generated when both the pulses collapse. Now when a metal comes in the range of the magnetic field, there is a change in the amplitude and phase of the pulse in the received coil. Planar square spiral coil is the geometry best suited for increasing depth sensitivity. It depends on the parameters such as fill ratio and spacing to width ratio. A coil with a higher fill ratio is shown to have higher size sensitivity and a coil with a smaller wire spacing-to-width ratio is shown to have higher depth sensitivity. Using this Pulse Induction Metal Detector we build a robotic vehicle.

Metal-ceramic nanocomposite coatings have been applied to many industrial applications owing to their remarkable properties such as wear, corrosion and high temperature oxidation resistance than that of metals and alloys in high temperature environments. In this study, YSZ and Ni-YSZ nanocomposite coatings deposited by electron beam physical vapour deposition (EBPVD) for high temperature environments have been investigated. Initially friction and wear behaviour of YSZ coatings deposited at various substrate temperature were studied. Then the effect on wear response of Ni-YSZ nanocomposites with different Ni content were investigated using a ball-on-disc micro tribometer. The structural and tribochemical changes that occurred in the wear tracks of YSZ and Ni-YSZ coatings were investigated using field emission scanning electron microscopy and Raman spectroscopy. The results obtained on sliding wear and friction behaviour of these nanocomposite coatings suggest that 50 wt.% of Ni in YSZ nanocomposite provides good wear resistance behaviour than that of other coatings. Such an improvement in tribomechanical and wear performance of the nanocomposite coating could be attributed to the optimum amount of Ni which promotes the formation of NiO from Ni due to the frictional heat between nanocomposite coating and the sliding counter body in wear track as confirmed by Raman analysis.

Utilization of nanoparticles have seen significant growth as a filler material in different technological and product development. Iron oxide particles are found important due to their special characteristics such as; natural high abundance, low cost, robustness, low toxicity, high surface to volume ratio etc. The preparation of iron oxide nanoparticles using Wealth out of Waste (WoW) process is gaining much interest due to the economic point of view and environmental concern. In the current work, iron oxide nanoparticles with size 46 nm have been prepared by chemical method, using waste iron scrap obtained from mechanical lathe machines. Waste plastic and iron oxide nanoparticles, has been utilized in the pyrolysis process at 700 degrees C in a fixed bed pyrolysis reactor to prepare iron oxide-carbon composite. The electrochemical study of the composite was carried out and achieved specific capacitance to be 150 F/g and energy density to be 187.50 Wh/kg, which is comparable or even better than some other composite such as Fe3O4/CNT composite, Fe2O3 nanotube arrays, FeOOH rods and Fe3O4/CNF composite. The prepared Fe3O4-carbon composite is significant for reducing plastic waste, iron waste and providing low cost energy storage material. (C) 2021 Elsevier Ltd. All rights reserved.

High quality silver (Ag) decorated CeO 2 nanoparticles were prepared by a facile one-step chemical method. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), High resolution transmission electron microscopy (HR-TEM), fourier transform infrared spectrometer (FT-IR), electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS), UV–Visible absorption (UV–Vis), photoluminescence (PL) and thermogravimetric analysis. The decoration of Ag on CeO 2 surface was confirmed by XRD, EPR and HR-TEM analysis. Harmful textile pollutant Rose Bengal dye was degraded under sunlight using the novel Ag decorated CeO 2 catalyst. It was found that great enhancement of the degradation efficiency for Ag/CeO 2 compared to pure CeO 2 , it can be ascribed mainly due to decrease in its band gap and charge carrier recombination rate. The Ag/CeO 2 sample exhibited an efficient photocatalytic characteristic for degrading RB under visible light irradiation with a high degradation rate of 96% after 3 h. With the help of various characterizations, a possible degradation mechanism has been proposed which shows the effect of generation of oxygen vacancies owing to the decoration of Ag on the CeO 2 surface.