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This paper aims to analyze deeply the effect of surface roughness conditions of the common interface of the two-layered riveted cantilever beams on their frictional damping during free lateral vibration at first mode. Here, the product, (µ × α), and damping ratio, ξ, are the parameters whose variations are analyzed in this investigation. For this, the influencing parameters considered are the natural frequency of vibration, f; the amplitude of initial excitation, y; and surface roughness value, Ra.

For experimentally evaluating logarithmic damping decrement, d, the frequency response function analyzer for the case of free lateral vibrations was used. Later, for evaluating the product, µ × α (where µ is the kinematic coefficient of friction and α is the dynamic slip ratio), and then, the damping ratio, ξ, the empirical relation suggested for logarithmic damping decrement, d, of riveted cantilever beams was used. After this, the full and reduced quadratic models of the product, µ × α, ξ, response surface methodology (RSM) with the help of Design Expert 11 software was used. Corresponding main effects plots, surface plots and prediction comparison plots were obtained to observe the variations of the product, µ × α, ξ for the variations of influencing parameters: f, y and Ra. Finally, a machine learning technique such as artificial neural networks (ANNs) using “nntool” present in MATLAB R13a software was used to predict the ξ for the different combinations of f, y and Ra.

The full and reduced quadratic regression models for the product, (µ × α) and the damping ratio, ξ of riveted cantilever beams for free lateral vibrations of the first mode in terms of the parameters: f, y and Ra were obtained. In addition, the main effects plots, surface plots and prediction comparison plots for the product, µ × α, ξ, with the corresponding experimental values of the product, µ × α, ξ, were obtained. Also, the execution of ANNs using MATLAB R13a software is proved to be the more accurate tool for the prediction of damping ratios in comparison to quadratic regression equations obtained from Design Expert 11 software. In the end, the assumption that the effect of surface roughness value on the product, (µ × α), and the damping ratio, ξ, is negligible is proved to be true using the main effects plots for the product, (µ × α) and ξ obtained from the Design Expert 11 software.

Obtaining the full and reduced quadratic regression equations for the product, (µ × α), and ξ of the two-layered riveted cantilever beams in terms of parameters: f, y and Ra was done. In addition, the conditions for the corresponding minimum and maximum values of the product, (µ × α), and ξ were obtained. Later, the main effects plots, surface plots and comparison plots of the predicted product, (µ × α), and ξ versus experimental product, (µ × α), and ξ were also obtained. Finally, the predicted values of the product, (µ × α), and ξ using the ANNs tool are observed to be the more accurate values in comparison to that obtained from RSM using the Design Expert 11 software.

To assess knowledge, perceptions and practices of grassroots‐level food safety regulators.

Knowledge, attitude and practices (KAP) study using quantitative and qualitative methods for data collection. Quantitative data was collected using a pre‐tested knowledge assessment questionnaire. Qualitative data was collected by conducting a focus group discussion (FGD) and six in‐depth interviews among food safety regulators from all 23 districts of the South Indian state of Andhra Pradesh. Quantitative data were analysed using SPSS package (version 14.5). The FGD and in‐depth interviews' recordings were transcribed verbatim and translated into English before compiling them into individual reports. These reports were read independently by a group of researchers before inferences were drawn.

The respondents' knowledge on basic food microbiology was limited. They attributed their inability to monitor all cases of food poisoning/adulteration to delay in receiving information and lack of laboratory facilities. They had sound knowledge of conventional adulterations, but were not equipped to check newer adulterations. Their knowledge on health/nutrition claims on food labels is almost nil. Orientation towards food safety issues other than adulteration is the need of the hour.

The results of the study can serve as the basis for developing an in‐service training module for food safety regulators.

Introduction Welding and brazing fall into the broad category of engineering joints, where the former is a stronger joint than the latter. Nevertheless, both these joints are heterogeneous and are susceptible to environmental effects, in the form of enhanced corrosion, due to their retained residual stresses and matrix heterogeneity. Partial melting, micro structural transformation, diffusional alloy layer formation, etc. are some of the phenomena met within these joints. It is argued that relief of stresses, by heating these joints to appropriate temperatures, which are below the transformation temperature range, may deactivate the stress raiser sites, so that susceptibility to micro galvanic action is considerably reduced. Such treatment may also cause thermally‐activated reorganization of the micro structure, resulting in matrix uniformity. Such structural uniformity and stress matching may pay further for reducing the corrosion loss by reduction of micro‐galvanic action.

Discusses the distress of mine rope‐wires, under the diverse states of stresses and strains of physical, chemical and mechanical origin. Mine rope‐wires undergo complicated cycles of stresses and strains inside the depth of coal and metal mines. This assumes special significance during summer inside the deeper mines. Summarizes recent studies in this field and compares their results.

Carbon steels are abundantly employed in our day‐to‐day engineering services, the automotive industry, and in various domestic usages. Service life of carbon steel assumes importance, as faults bring either costly industrial downtime or embarrassing domestic inconvenience. It appears that these materials are dependent completely on the solubility of carbon in their solid‐solutions. Instabilities and destabilization mainly occur due to separation of various forms of carbides, which embrittles the matrix in the time domain. The presence of residual stress which is trapped inside the matrix, having originated from the previous deformation stresses of the wrought products, accelerates such precipitation. Thermal treatment, such as the subcritical stress relieving process, may also accelerate such an embrittlement process, although this exercise is meant for the relief of the matrix residual stresses only. Concludes that there is simultaneous precipitation of brittle phases and also deactivation of the matrix, owing to stress relieving. A surface becomes electrochemically more active when the precipitation component more than compensates the deactivation component and vice versa. Improvement of the matrix ductility also works against such deterioration processes. Suggests that imposition of the environmental constraints, such as aggressive and corrosive media, can only accelerate deterioration, by activating the brittle precipitation cycle.

Sensitization of stainless steels has been posing serious problems to the industries. Techniques for rapid detection of sensitized surfaces are being probed throughout the world. Characterization over a wide behavioural range is essential for the above. Characterizes sensitized surfaces of AISI 304 stainless steel using impedance and tafel‐extrapolation techniques. Welded 304 stainless steel interfaces were subjected to dissolution tests, in different media, for assessing the effect of prolonged post‐stress relieving on the mitigation of surface dissolution. The corrosion rate values were correlated with the period of sensitization and Huey test results. The sensitized stainless steels were also subjected to electrochemical tests in different solutions. From the impedance behaviour of the sensitized surfaces in 3 per cent NaCl electrolyte, it was observed that the rate of fall in the polarization resistance may be used to monitor the extent of sensitization in 304 stainless steel, with better accuracy, than that in utilizing the polarization resistance itself.

Unsafe food can lead to various foodborne diseases and even death, especially among children. This paper aims to assess food safety knowledge and changes in practices and concerns among adults ≥ 18 years during the coronavirus disease 2019 (COVID-19) pandemic.

A cross-sectional, web-based survey was conducted among 325 adults living in Northern India. Demographic data and information regarding their knowledge, practices and concerns about various food safety issues were collected to see if there were any changes due to the COVID-19 pandemic.

The results showed that the participants had slightly higher than average knowledge and good food safety practices with mean scores of 9.75 ± 2.23 and 24.87 ± 2.28, respectively. Contracting COVID-19 from food and food packaging materials was of high concern for more than 70% of the participants. Majority (> 80%) of them reported an increase in the frequency of handwashing. About 16% of the participants used chemical disinfectants for washing fruits and vegetables. An increase (57.5%) in the frequency of food label reading was also noted during the pandemic. Freshness and the general quality of food items (49.5%), safety of food (30.8%) and cost (18.2%) were the top drivers that influenced the purchase decision.

This study highlighted the need to send out clear messages on safe food handling practices and keeping the tempo up for sustaining good hygienic practices. This will help in reducing the risk of foodborne diseases.

Non-performing assets (NPAs) are classified as loans and advances which are in default, either refund of principal or interest payments are not duly met. This not only leads to dishonour of loan agreement from the recipients' point of view but also huge NPAs result macroeconomic instability and economic crisis. The financial crisis may create hindrances towards achievement of sustainable development of an economy. Keeping NPA in balance sheet portrays lacunae in management of the lender. The non-recovery of interest and principal reduces the lender's operating cash flow, which upsets the budget and drops the earnings. Statutory provisions, set aside to cover probable losses, reduce the income further. When the non-recovery is determined to be definite in nature, they are written off against earnings of the lending institution. Thus, presence of NPAs in balance sheet gives a distress signal to the stakeholders of the lending institution. Under this consideration, the present study will look upon some of these issues related to NPA management in Indian banking sector. The main objective of this study is to discuss the nexus between the NPA of Indian scheduled banks for priority sector, non-priority sector and public sector and the gross domestic product (GDP) of Indian economy for the time period 2005–2020. To study this objective, the ratio analysis and the trend analysis of NPA of three sectors and GDP of Indian economy over the given time frame have been done. Finally, some policy prescriptions regarding achievement of sustainable development after taking into account NPA management of an economy have also been proposed.

Mine rope‐wire profile is prone to stress concentration zones by virtue of its manufacturing style and reveals a metastable surface. Metastability, being a non‐equilibrium state, tends to revert back to stability. Such a process of reversion may generate a number of non‐equilibrium states on the surface, which in contact with the mining‐environment foster the growth of a stable and adherent passive‐film.

The purpose of this paper is to present the results of acoustic emission (AE) and ultrasonic inspection of two H₂S storage tanks carried out in a heavy water plant, in order to characterize point type defects observed during earlier ultrasonic inspection and to ensure that these defects are not growing during hydrotesting of the tanks.

Using multiple AE sensors and AE source location methodology, the entire tank could be covered to detect and locate any dynamic sources of AE associated with local plastic deformation and/or growing discontinuities from any part of the tank during the hydrotest. For confirmation of the results obtained by AE, ultrasonic inspection on the tanks and on virgin plates from which the tanks were manufactured, were carried out.

The AE signals generated during first pressurisation are attributed to the micro yielding of the material of the tanks. A few scattered AE events were observed at a few locations during the hydrotesting of the tanks and these are due to structural and rubbing noise. During hold periods and repressurising cycle of the hydrotesting, no detectable AE events were observed and this confirmed the absence of any growing discontinuity in the tanks during the hydrotesting. Ultrasonic inspection on the tanks and on virgin plates confirmed that the point type defects detected are manufacturing defects and not formed during service life.

The combined results from AE and ultrasonic techniques confirmed the structural integrity of the tanks and ensured their healthiness for continued operation.

The paper brings out the use of AE and ultrasonic techniques for monitoring hydrotesting of storage tanks of a heavy water plant. The storage tanks where point type defect indications were reported during previous ultrasonic inspection and whether these defects are growing during hydrotesting of the tanks or not, were required to be known before the tanks are put in to further service. AE signals collected during pressurising and repressurising cycles of the hydrotest and subsequent inspection by ultrasonic confirmed the vessels to be free from growing defects during the hydrotest and provided baseline data for future inspection.