Recently, there has been a tremendous rise in production of portable electronic devices. To produce flexible devices, flexible substrates should replace conventional glass substrates. Indium-tin-oxide (ITO) is the preferred transparent conducting layer used in the display technology. Although ITO has excellent sheet resistance and very good optical properties, ITO can crack at very low tensile strains which might cause failure in the conductive layer because of the unusual structure of a very thin film of brittle ceramic material applied to a polymer substrate. Therefore, the mechanics of ITO on flexible substrates has been thoroughly considered in the design and manufacturing of flexible devices. In a typical roll-to-roll manufacturing process, many challenges exist during the travel of the coated web over the rollers which produce bending stresses that might cause failure even if the stresses are below the yield strength of the material. Therefore, the high cycle bending fatigue of ITO thin films on flexible substrates is of a significant importance. In this work, high cycle bending fatigue experiments were conducted on ITO coated PET substrate. The effect of bending diameter, bending frequency, and sample width on the change in electrical resistance was investigated. High magnification images were obtained to observe crack initiation and propagating in the ITO layer. The goal of this work is to establish a baseline for a comprehensive reliability study of ITO thin films on flexible substrate. It was found that bending diameters as well as the number of bending cycles have a great influence on the electrical conductivity of the ITO layer.

Fatigue failure of solder joints is one of the major causes of failure in electronic devices. Fatigue life prediction models of solder joints were first put forward in the early 1960s, and since then, numbers of methods were used to model the fatigue mechanism of solder joints. In this article, the majority fatigue life models are summarized, with emphasis on the latest developments in the fatigue life prediction methods. All the models reviewed are grouped into four categories based on the factors affecting the fatigue life of solder joints, which are: plastic strain-based fatigue models, creep damage-based fatigue models, energy-based fatigue models, and damage accumulation-based fatigue models. The models that do not fit any of the above categories are grouped into “other models.” Applications and potential limitations for those models are also discussed.

Introduction: Current research about frontline nurse stress and turnover intention lacks context related to rural communities’ plight in providing organizational resources during the current COVID-19 pandemic. These implications have been particularly underexamined in the United States, whose regional differences may influence how frontline nurses perceive the access and utility of organizational resources. This study investigates if anxiety and stress while working during the current COVID-19 pandemic contribute to frontline nurses’ desire to leave their current position in Alabama hospital settings. Material and Methods: A cross-sectional survey was developed and distributed as a Qualtrics survey to frontline nurses using social media and professional contacts. A total of 111 frontline nurse respondents within May 19–June 12, 2020 were included in this study. Results: A significant correlation was found between gender (p= 0.002), marital status (p= 0.000) and seniority (p= 0.049) on turnover intention. A nurse’s perceived anxiety and stress related to their patients’ acuity (r= 0.257, p= 0.004), their personal health as a risk factor (r= 0.507, p= 0.000), their patient assignments (r= 0.239, p= 0.01), their personal protective equipment (r= 0.412, p= 0.000), and their psychological support (r= 0.316, p= 0.001) correspond to higher turnover intention among nurses working with patients infected with COVID-19. Conclusion: Perceived resource loss in task autonomy, PPE, and psychosocial support increased turnover intention among frontline nurses in Alabama. Research is needed to understand how intrinsic motivations and social support influence individual nurse staff’s perceptions of resource loss and job demands. Further, more research is necessary to examine the implications of rurality and place in discussing turnover intention and organizational resources across multiple health systems.

Indium-tin-oxide (ITO) is a transparent conductive thin film that is widely used as a top conducive layer in photovoltaic solar cells. However, ITO is sensitive to environmental conditions and the electrical conductivity degrades as a consequence of harsh environmental conditions. Furthermore, the thermal expansion coefficient mismatch between the ITO film and the substrate creates stress/strain on the film when the package is subjected to fluctuating temperatures. This could create micro-cracks and consequently damage the film. Therefore, this study was designed to study the effect of the thermal cycling and thermal aging on the ITO thin films to simulate the effect of continuous high temperatures and fluctuating temperatures that may be applied on the thin films during the usage. In this study, two sets of experiments were conducted on a 60Ω/□square sputter-deposited ITO on 127 μm heat stabilized Poly Ethylene Terephthalate (PET) substrate. The first set of experiments contained four samples which were thermally aged at 100^°C for 30 days and the other set of experiments contained another four samples which were thermally cycled for 900 cycles. The thermal profile consisted of a high temperature of 100^°C, a low temperature of 0^°C, dwell time of 10 minutes, and ramp rate of 10^°C/min , as depicted in Fig. 1. The initial results showed that the ITO thin film is not stable in the thermal aging experiment and the electrical resistivity gradually increased for all samples until the end of the 30 days. The degradation happened during the thermal cycling as well. However, SEM images show that the morphology of the ITO surface is stable under both conditions. Energy-dispersive X-ray (EDX) spectroscopy analysis showed stability in the ITO thin film in terms of composition. XRD spectra confirmed the improved crystallinity for the thermally aged films, which corresponded to the increased transmission in the visible region.

Selecting the appropriate maintenance type is a challenging task that involves multiple criteria working together. This decision has a significant impact on the organization and its overall market sustainability. The primary categorization of maintenance consists of two main types: corrective maintenance and preventive maintenance. All other classifications are encompassed within these two categories. For instance, preventive maintenance can be further classified as either predictive maintenance or periodic maintenance. Given the importance of this decision, this paper discusses the optimal maintenance type under different conditions. The scale of the business, the cost of machine failure, the effect of machine failure on the production schedule, the effect of machine failure on worker safety and the workplace environment, the availability of spare parts, the lifespan of the machine, and the manufacturing process are some of the factors that are covered in this paper. This paper primarily aims to present a comprehensive literature review concerning the strategic decision-making process for selecting the appropriate maintenance type under varying conditions. Additionally, the paper incorporates various models and visual aids within its content to facilitate and guide the decision-making procedure. Corrective maintenance is usually necessary in the case of small companies, significant impact on business or production plans due to failures, potential risks to public safety, ready availability of spare parts, and when production processes are not interdependent. If these parameters are not met, preventive maintenance can be a better option. Since these circumstances frequently do not occur simultaneously, it is imperative for the business to give them significant consideration.

Normally distributed data is crucial for the application of large-scale statistical analysis. To statisticians, the most important assumptions of statistical users are the adequacy of the data and the normal distribution of the data. However, users are constantly forced to deal with unusual data. This includes changing the method used to be less sensitive to non-normal data or transforming that data to normal data. In addition, common mathematical transformation methods (for example, Box-Cox) do not work on complex distributions, and each method works on limited data shapes. In this paper, a novel approach is presented to transform any data into normally distributed data. We refer to our approach as the Ultra-fine transformation method. The article's novelty is that the proposed approach is powerful enough to accurately transform any data with any distribution to the standard normal distribution. Besides this approach's usefulness, it is simple in both theory and in application, and users can easily retrieve the original data from its transformed state. Therefore, we recommend using this method for the data used in the statistical method, even if the data are normal.