Nonlinear transverse vibration of a micro‐size moving beam like structure under the influence of thermal conditions is studied. Hamilton principle is used to derive the nonlinear equation of motion. ...The derived equation of transverse motion is discretized using the Galerkin technique. The vibration attributes of the moving beam, such as frequencies of the transverse response, time response, and stability analysis, are investigated at different temperatures. For stability analysis, bifurcation diagrams are presented under the influence of temperature, length‐scale parameter, and excitation frequencies at various axial speeds of the beam.
Control charts are effective tools to distinguish between special and natural variations and have applications in medical and business industries besides manufacturing industry. Due to the ...advancement of modern technology, we often deal with the high-quality products, where the traditional process monitoring techniques have certain drawbacks. This article presents a control chart for jointly monitoring time and magnitude based on the renewal reward process. In particular, the focus of this study is to model magnitudes by threshold exceedance. More specifically, assuming a random failure threshold, two cases for magnitude are considered: (i) magnitude is cumulative over time and, (ii) magnitude is non-cumulative or independent over time. A comparative study to show the effectiveness of the proposal is also a part of this study.
Control charts are essential tools to monitor the quality of a process and commonly used in many industries besides industrial production. Due to the industrial revolution, many products have very ...low failure chances and labeled as the high‐quality products, where the time‐between‐events (TBE) charts are commonly used to monitor such processes. This study purposes control charts to monitor time and magnitude assuming the power law process for the TBE whereas the magnitude is assumed cumulative as well as noncumulative over time. Besides two illustrative examples, a comparison to the existing rate and first passage time (FPT) charts is also presented in this study. It is shown numerically that the proposed charts are more efficient than the existing FPT and rate charts.
Teachers’ education has a pivotal role in the process of societal change and for leading towards a sustainable future. The current study aimed at investigating the effect of a course regarding ...education for sustainable development on the student-teachers’ attitude towards sustainable development. The data were collected from student teachers in two stages; in the first stage, data were collected from 287 students to validate the questionnaire while in the second stage data were collected from the experimental and controlled group. Structural equation modelling technique, paired and independent sample t-tests were applied for data analysis. The results of the quantitative and qualitative data indicate a positive change in the student-teachers’ attitude towards sustainable development. Student-teachers who studied education for sustainable development subject during their course-work were surveyed to determine if they had a positive attitude towards sustainable development compared to their counterpart student-teachers who did not study education for sustainable development subject. Results of the study advocate the need and potential of education for sustainable development in different academic programs, especially teachers’ education program in Pakistan, is to enhance the students’ attitude towards sustainable development.
•Education for Sustainable Development (ESD) plays a significant role in sustainable future.•Analysis of ESD course on pre-service teachers’ attitude and behaviour towards sustainable development (SD).•A significant increase in student-teachers’ attitude towards sustainable development (SD) after studying the ESD course.
A fundamental problem with all process monitoring techniques is the requirement of a large Phase‐I data set to establish control limits and overcome estimation error. This assumption of having a ...large Phase‐I data set is very restrictive and often problematic, especially when the sampling is expensive or not available, eg, time‐between‐events (TBE) settings. Moreover, with the advancement in technology, quality practitioners are now more interested in online process monitoring. Therefore, the Bayesian methodology not only provides a natural solution for sequential and adaptive learning but also addresses the problem of a large Phase‐I data set for setting up a monitoring structure. In this study, we propose Bayesian control charts for TBE assuming homogenous Poisson process. In particular, a predictive approach is adopted to introduce predictive limit control charts. Beside the Bayesian predictive Shewhart charts with dynamic control limits, a comparison of the frequentist sequential charts, designed by using unbiased and biased estimator of the process parameter, is also a part of the present study. To assess the predictive TBE chart performance in the presence of practitioner‐to‐practitioner variability, we use the average of the average run length (AARL) and the standard deviation of the in‐control run length (SDARL).
This study analyzes the non-linear relationship between urbanization and CO
2
emissions over the period 1971 to 2014 in Indonesia. The findings unveil an inverted U-shaped relationship between ...urbanization and CO
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emissions. Urbanization increases CO
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emissions, but after achieving a certain level, it negatively impacts emissions. Economic growth and energy intensity increase CO
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emissions, while trade openness has no significant effect on CO
2
emissions. Further, we have validated the robustness of results by using the ecological carbon footprint as a proxy of environmental degradation. The results of the causality test show unidirectional causality running from economic growth to emissions and energy intensity, and feedback effect between urbanization and emissions. Finally, several policy measures are proposed to improve the environment without reducing the urbanization level.
This article introduces Bayesian predictive monitoring of time-between-events using Cumulative Sum (CUSUM) and Exponentially Weighted Moving Average (EWMA) control charts with predictive control ...limits. It is shown that the proposed methodology not only overcomes the requirement of a large Phase-I data set to establish control limits, but also feasible for online process monitoring. In addition to Bayesian memory-type charts with dynamic control limits, a comparison of the frequentist sequential charts, designed by using the unbiased and biased estimator of the process parameter, is also given in this article. For the performance evaluation of the predictive TBE chart in the presence of practitioner-to-practitioner variability, we use the average of the in-control average run length (AARL) and the standard deviation of the in-control run length (SDARL).
The traditional process monitoring techniques used to study high‐quality processes have several demerits, that is, high‐false alarm rate and poor detection, etc. A recent and promising idea to ...monitor such processes is the use of time‐between‐events (TBE) control charts. However, the available TBE control charts have been developed in a nonadaptive fashion assuming the Poisson process. There are many situations where we need adaptive monitoring, for example, health, flood, food, system, or terrorist surveillance. Therefore, the existing control charts are not useful, especially in sequential monitoring. This article introduces new adaptive TBE control charts for high‐quality processes based on the nonhomogeneous Poisson process by assuming the power law intensity. In particular, probability control limits are used to develop control charts. The proposed methodology allows us to get control limits that are dynamic and suitable for online process monitoring with an additional advantage to monitor a process where we believe the underlying failure rate may be changing over time. The average run length and coefficient of variation of the run length distribution are used to assess the performance of the proposed control charts. Besides simulation studies, we also discuss three examples to highlight the application of the proposed charts.
Plant growth-promoting rhizobacteria (PGPR) actively colonize the plant rhizosphere, which not only stimulates plants’ growth and development but also mitigates the adverse effects of abiotic ...stressors. Besides other techniques and approaches used for the alleviation of abiotic stress conditions, the utilization of PGPR with multiplant growth-promoting traits is desirable because the application of PGPR is pragmatic, sustainable, and environmentally friendly. In the past four decades, numerous ACC deaminase-producing PGPR have been reported for the improvement of crop plants’ growth and development under different abiotic stress conditions. Since 1-aminocyclopropane-1-carboxylate (ACC) deaminase producing PGPR regulates ethylene production by utilizing the exuded ACC, which is an immediate precursor of ethylene biosynthesis. However, little is known about the basic mechanism involved in the acquisition of ACC by ACC deaminase-producing bacteria since the enzyme ACC deaminase is localized inside the bacterial cells and ACC is exuded into the rhizosphere from plant roots. In the present article, we proposed candidate attractants involved in the transfer of ACC into ACC deaminase-producing bacteria. Additionally, we discussed the importance and relation of these candidate attractants with ACC deaminase under abiotic stress conditions.
Key points
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The ethylene precursor, ACC, exude from plant tissues under abiotic stresses
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ACC deaminase activity of PGPR localized in the cytoplasm and periplasm of bacteria
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Proposed candidate attractants for the transfer and equilibrium of exuded ACC
Two-dimensional van der Waals materials have emerged as promising platforms for solid-state quantum information processing devices with unusual potential for heterogeneous assembly. Recently, bright ...and photostable single photon emitters were reported from atomic defects in layered hexagonal boron nitride (hBN), but controlling inhomogeneous spectral distribution and reducing multi-photon emission presented open challenges. Here, we demonstrate that strain control allows spectral tunability of hBN single photon emitters over 6 meV, and material processing sharply improves the single photon purity. We observe high single photon count rates exceeding 7 × 10
counts per second at saturation, after correcting for uncorrelated photon background. Furthermore, these emitters are stable to material transfer to other substrates. High-purity and photostable single photon emission at room temperature, together with spectral tunability and transferability, opens the door to scalable integration of high-quality quantum emitters in photonic quantum technologies.Inhomogeneous spectral distribution and multi-photon emission are currently hindering the use of defects in layered hBN as reliable single photon emitters. Here, the authors demonstrate strain-controlled wavelength tuning and increased single photon purity through suitable material processing.
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