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The purpose of the study is to highlight the potential of the sensor based smartphone in assessing the covid-19 cases. Coronavirus disease 2019 (COVID-19) is a noxious pandemic affecting the respiratory system of the human and leading to the severe acute respiratory syndrome, sometimes causing death. COVID-19 is a highly transmittable disease that spreads from an infected person to others. In this regard, a smart device is required to monitor the COVID-19 infected patients by which widespread pandemic can be reduced.

In this paper, an electrochemical sensor-enabled smartphone has been developed to assess the COVID-19 infected patients. The data-enabled smartphone uses the Internet of Things (IoT) to share the details with the other devices. The electrochemical sensor enables the smartphone to evaluate the ribonucleic acid (RNA) of COVID-19 without the nucleic acid and feeds the data into the data server by using a smartphone.

The obtained result identifies the infected person by using the portable electrochemical sensor-enabled smartphone, and the data is feed into the data server using the IoT. Whenever an infected person moves outside the restricted zone, the data server gives information to the concerned department.

The developed electrochemical sensor-enabled smartphone gives an accuracy of 81% in assessing the COVID-19 cases. Thus, through the developed approach, a COVID-19 infected person can be identified and the spread can be minimized.

The purpose of the research is to concentrate on the most important smart metropolitan applications which are smart living, smart security and smart maintainable. In that, Power management and security is a most important problem in the current metropolitan situation.

A smart metropolitan area utilizes recent innovative technologies to improve its living, security and maintainable. The aim of this study is to recognize and resolve the difficulties in metropolitan area applications.

The main aim of this study is to reduce the metropolitan foremost energy consumption, to recharge the electric vehicles and to increase the lifetime of smart street lights.

The hybrid renewable energy street light applies smart resolutions to substructure and facilities in rural and metropolitan areas to create them well. This study will be applying smart metropolitan solar and wind turbine street light using renewable energy for existing areas. In future, the smart street light work will be implemented everywhere else.

A large increase in robberies of convenience stores in New Zealand (NZ) in 2016 and 2017 was anecdotally attributed to persistent and substantial increases in excise tax on tobacco products. This study aims to explore the validity of that claim by examining the characteristics of the robberies through the lens of online news coverage.

Google, Bing and main online NZ news outlets were searched for news reports between 2009 and 2018 of tobacco-related store robberies. Content analysis was used to extract characteristics such as date of robbery, type of store, items targeted or stolen and demographic profile of offenders. The prevalence of reported robberies by socioeconomic level of the surrounding community was assessed using nearest primary school decile rating. Descriptive statistics and statistical analysis were used to discuss trends and key findings in the data.

Reports on 572 robberies were unevenly distributed across the years with a large increase in 2016 and 2017, followed by a substantial decrease in 2018. Local community convenience stores were primarily hit – more so in lower socioeconomic communities. Robberies occurred nationwide and disproportionately so during colder months in lower socioeconomic communities. Many robberies were aggravated resulting in serious injury to shopkeepers. Tobacco and cash were predominantly targeted.

The large increase in robberies that occurred in 2016–2017 likely resulted from tax-driven tobacco price hikes combined with reduced duty-free tobacco coming into NZ with travellers. Installation of security in stores, news fatigue and other explanations are potential reasons for the 2018 decrease in reported robberies despite tobacco prices increasing. Frequent robberies of local stores, many including violence, should be a public health concern as destruction of community well-being can be a determinant of other health problems. The negative consequences for communities, particularly lower socioeconomic communities, need to be factored into the cost benefit analysis of raising the tax on tobacco.

This study provides much needed detail on the negative health and social consequences of tobacco-related store robberies.

This study aims to outline the current challenges in ultrasonic additive manufacturing (AM). AM has revolutionized manufacturing and offers possible solutions when conventional techniques reach technological boundaries. Ultrasonic additive manufacturing (UAM) uses mechanical vibrations to join similar or dissimilar metals in three-dimensional assemblies. This hybrid fabrication method got attention due to minimum scrap and near-net-shape products.

This paper reviews significant UAM areas in process parameters such as pressure force, amplitude, weld speed and temperature. These process parameters used in different studies by researchers are compared and presented in tabular form. UAM process improvements and understanding of microstructures have been reported. This review paper also enlightens current challenges in the UAM process, process improvement methods such as heat treatment methods, foil-to-foil overlap and sonotrode surface roughness to increase the bond quality of welded parts.

Results showed that UAM could solve various problems and produce net shape products. It is concluded that process parameters such as pressure, weld speed, amplitude and temperature greatly influence weld quality by UAM. Post-weld heat treatment methods have been recommended to optimize the mechanical strength of ultrasonically welded joints process parameters. It has been found that the tension force is vital for the deformation of the pre-machined structures and for the elongation of the foil during UAM bonding. It is recommended to critically investigate the mechanical properties of welded parts with standard test procedures.

This study compiles relevant research and findings in UAM. The recent progress in UAM is presented in terms of material type, process parameters and process improvement, along with key findings of the particular investigation. The original contribution of this paper is to identify the research gaps in the process parameters of ultrasonic consolidation.

This paper presents the effects of replacing fine aggregate (FA) with waste foundry sand (WFS) in natural aggregate and construction waste aggregate concrete specimens without and with superplasticizer (SP), silica fume (SF) and fiber (F) to solve the disposal problems of various wastes along with saving the environment. This study aims to investigate the effect of construction waste, WFS along with additives on the stress-strain behavior and development of compressive strength with age.

The various concrete specimen were prepared in mix proportion of 1: 2: 4 (cement (C): sand: coarse aggregate). The water-cement ratio of 0.5 (decreased by 10% for samples containing SP) to grading 1: 2: 4 under air-dry condition was adopted in the preparation of concrete specimens. The compressive strength of various concrete specimen were noticed for 3, 7 and 28 days by applying load through universal testing machine.

Upon adding construction and demolition waste aggregates, the compressive strength of concrete after 28 days was comparable to that of the control concrete specimen. An enhancement in the value of compressive strength is perceived when FA is replaced with WFS to the extent of 10%, 20% and 30%. If both construction and demolition waste aggregate and WFS replacing FA are used, the compressive strength increases. When FA is interchanged with WFS in natural aggregate or construction demolition waste aggregate concrete including usage of SF or F, the compressive strength improves significantly. Further, when construction and demolition waste aggregate and WFS replacing FA including SP are used, the compressive strength improves marginally compared to that of control specimen. The rate of strength development with age is observed to follow similar trend as in control concrete specimen. Therefore, construction and demolition waste and or WFS can be used effectively in concrete confirming an improvement in strength.

The utilization of these wastes in concrete will resolve the problem of their disposal and save the environment.

Since the biomedical implants with an improved compressive strength, near bone elastic modulus, controlled porosity, and sufficient surface roughness, can assist in long term implantation. Therefore, the fine process tuning plays its crucial role to develop optimal settings to achieve these desired properties. This paper aims to find applications for fine process tuning in laser powder bed fusion of biomedical Ti alloys for load-bearing implants.

In this work, the parametric porosity simulations were initially performed to simulate the process-induced porosity for selective laser-melted Ti₆Al₄V as per full factorial design. Continually, the experiments were performed to validate the simulation results and perform multiresponse optimization to fine-tune the processing parameters. Three levels of each control variable, namely, laser power – Pl (180, 190, 200) W, scanning speed – Vs (1500, 1600, 1700) mm/s and scan orientation – ϴ{1(0,0), 2(0,67°), 3(0,90°)} were used to investigate the processing performance. The measured properties from this study include compressive yield strength, elastic modulus, process-induced porosity and surface roughness. Finally, confirmatory experiments and comparisons with the already published works were also performed to validate the research results.

The results of porosity parametric simulation and experiments in selective laser melting of Ti₆Al₄V were found close to each other with overall porosity (less than 10%). The fine process tuning was resulted in optimal settings [Pl (200 W), Vs (1500 mm/s), ϴ (0,90°)], [Pl (200 W), Vs (1500 mm/s), ϴ (0,67°)], [Pl (200 W), Vs (1500 mm/s), ϴ (0,0)] and [Pl (200 W), Vs (1500 mm/s), ϴ (0,0)] with higher compressive strength (672.78 MPa), near cortical bone elastic modulus (12.932 GPa), process-induced porosity (0.751%) and minimum surface roughness (2.72 µm). The morphology of the selective laser melted (SLMed) surface indicated that the lack of fusion pores was prominent because of low laser energy density among the laser and powder bed. Confirmatory experimentation revealed that an overall percent improvement of around 15% was found between predicted and the experimental values.

Since no significant works are available on the collaborative optimization and fine process tuning in laser powder bed fusion of biomedical Ti alloys for different load bearing implants. Therefore, this work involves the comprehensive investigation and multi-objective optimization to determine optimal parametric settings for better mechanical and physical properties. Another novel aspect is the parametric porosity simulation using Ansys Additive to assist in process parameters and their levels selection. As a result, selective laser melted Ti alloys at optimal settings may help in examining the possibility for manufacturing metallic implants for load-bearing applications.

This study aims to fabricate an electrospun scaffold by combining radish (Ra) and cerium oxide (CeO₂) into a polyurethane (PU) matrix through electrospinning and investigate its feasibility for cardiac applications.

Physicochemical properties were analysed through various characterization techniques such as scanning electron microscopy (SEM), Fourier transforms infrared transforms analysis (FTIR), contact angle measurements, thermal analysis, atomic force microscopy (AFM) and mechanical testing. Further, blood compatibility assessments were carried out through activated partial thromboplastin time (APTT) and prothrombin time (PT) and hemolysis assay to evaluate the anticoagulant nature.

PU/Ra and PU/Ra/CeO₂ exhibited a smaller fibre diameter than PU. Ra and CeO₂ were intercalated in the polyurethane matrix which was evidenced in the infrared analysis by hydrogen bond formation. PU/Ra composite exhibited hydrophilic nature whereas PU/Ra/CeO₂ composite turned hydrophobic. Surface measurements depicted the lowered surface roughness for the PU/Ra and PU/Ra/CeO₂ compared to the pristine PU. PU/Ra and PU/Ra/CeO₂ displayed enhanced degradation rates and improved mechanical strength than the pristine PU. The blood compatibility assay showed that the PU/Ra and PU/Ra/CeO₂ had delayed blood coagulation times and rendered less toxicity against red blood cells (RBC’s) than PU.

This is the first report on the use of radish/cerium oxide in cardiac applications. The developed composite (PU/Ra and PU/Ra/CeO₂) with enhanced mechanical and anticoagulant nature will serve as an indisputable candidate for cardiac tissue regeneration.

This study aims to address the environmental impact of nondegradable synthetic materials by promoting their reuse. Specifically, it investigates the feasibility of using polyester needle felt carpet waste as the matrix for thermoplastic composites reinforced with glass and jute fibers at various fiber contents (20, 30 and 40 Wt. %).

The research used both glued and unglued carpet wastes to examine the effect of adhesive impurities on composite properties. The mechanical properties of the composites were evaluated through tensile, bending and Izod impact tests. Additionally, scanning electron microscopy was used to observe the microstructural effects of adhesive impurities on the fiber/matrix interface.

The results showed that unglued carpet composites outperformed glued carpet composites, exhibiting 51% greater tensile strength, 294% higher bending strength and 293% superior impact strength on average. The mechanical properties of the unglued carpet composites generally improved with increasing fiber content. In contrast, glued carpet composites demonstrated optimal performance at specific fiber contents within the studied range. Microscopic analysis revealed that adhesive impurities in the glued composites caused fiber/matrix bond disruption and delamination under load.

This study highlights the potential of recycling polyester needle felt carpet waste into high-performance thermoplastic composites. It underscores the significant impact of adhesive impurities on the mechanical properties of these composites and provides insight into optimizing fiber content for improved material performance.

Doppler-Bearing Tracking (DBT) is commonly used in target tracking applications for the underwater environment using the Hull-Mounted Sensor (HMS). It is an important and challenging problem in an underwater environment.

The system nonlinearity in an underwater environment increases due to several reasons such as the type of measurements taken, the speeds of target and observer, environmental conditions, number of sensors considered for measurements and so on. Degrees of nonlinearity (DoNL) for these problems are analyzed using a proposed measure of nonlinearity (MoNL) for state estimation.

In this research, the authors analyzed MoNL for state estimation and computed the conditional MoNL (normalized) using different filtering algorithms where measurements are obtained from a single sensor array (i.e. HMS). MoNL is implemented to find out the system nonlinearity for different filtering algorithms and identified how much nonlinear the system is, that is, to measure nonlinearity of a problem.

Algorithms are evaluated for various scenarios with different angles on the target bow (ATB) in Monte-Carlo simulation. Computation of root mean squared (RMS) errors in position and velocity is carried out to assess the state estimation accuracy using MATLAB.

This paper aims to target tracking in the marine environment is typically obtained by considering the measurement parameters like frequency, elevation and bearing. Marine environmental surveillance provides critical information and assistance for the exploitation and maintenance of marine resources.

With the use of intelligent sensor techniques like Hull-mounted and towed array sensors, convenient, precise and dependable three-dimensional (3D) underwater target tracking is introduced.

This research investigates a method to develop a reliable Unscented Kalman Filter (UKF) algorithm for enhanced underwater target tracking in a 3D scenario by using bearing, frequency and elevation measurements. In applications for underwater target tracking, uncertainty and inaccuracies are typically described by using Gaussian additive noise.

The proposed UKF algorithm is tested and analyzed using 100 Monte Carlo simulations with the Gaussian generated noise.