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This paper aims to reproduce the electrical connector intermittent fault behaviours with step-up vibration stress while maintaining the integrity of the product.

A dynamic model of an electrical connector under vibration is established for contact resistance analysis. Next, the dynamic characteristics of contact resistance are analysed, and cumulative damage theory is used to calculate the damage under different stresses during the intermittent fault reproduction test. To reduce damage and improve efficiency, the step-up stress is used for the reproduction test.

The proposed method can reproduce the intermittent fault behaviour, and the step-up stress test is more efficient than the constant stress test.

Step-up stress is used for intermittent fault reproduction, and the quantitative relationships between intermittent fault and product damage can be further studied.

It is expected that the proposed methodology can help engineers to reproduce the intermittent fault behaviours to facilitate the detection and diagnosis of intermittent fault and to improve equipment safety.

The mechanism of electrical connector reproduction is analysed and the step-up stress test is used for intermittent fault reproduction.

This paper aims to review comprehensively the different voltage-boosting techniques and classifies according to their voltage gain, stress on the semiconductor devices, count of the total components and their prominent features. Hence, the focus is on non-isolated step-up converters. The converters categorized are analyzed according to their category with graphical representation.

Many converters have been reported in recent years in the literature to meet our power requirements from mill watts to megawatts. Fast growth in the generation of renewable energy in the past few years has promoted the selection of suitable converters that directly impact the behaviour of renewable energy systems. Step-up converters are a fast-emerging switching power converter in various power supply units. Researchers are more attracted to the derivation of novel topology with a high voltage gain, low voltage and current stress, high efficiency, low cost, etc.

A comparative study is done on critical metrics such as voltage gain, switch voltage stress and component count. Besides, the converters are also summarized based on their advantages and disadvantages. Furthermore, the areas that need to be explored in this field are identified and presented.

Types of analysis usually performed in dc converter and their needs with the areas need to be focused are not yet completely reviewed in most of the articles. This paper gives an eyesight on these topics. This paper will guide the researchers to derive and suggest a suitable topology for the chosen application. Moreover, it can be used as a handbook for studying the various topologies with their shortfalls, which will provide a way for researchers to focus.

A typical photovoltaic grid-connection power system usually consists of multi-stage converters to perform multiple functions simultaneously. To simplify system configuration, reduce cost and improve conversion efficiency, this paper aims to develop a buck–boost-type inverter. The proposed inverter has both step-up and step-down functions, so that it is suitable for applications with wide voltage variation. As only one power switch operates with high frequency at one time, switching losses can significantly be reduced.

A step-up/down inverter is developed by adopting a buck-interleaved buck–boost (BuIBB) DC-DC converter and connecting with an H-bridge unfolding circuit with line-commutated operation.

The proposed circuit can work functionally as either a buck-type or boost-type inverter, so that partial energy can be directly delivered to output to improve efficiency. The input current is shared by two inductors, leading to the reduction of current stresses.

To apply the proposed inverter to micro-inverter applications in the future, developing a step-up/down inverter with a higher conversion ratio will be considered.

A laboratory prototype is built accordingly to verify the feasibility of the proposed inverter. The experimental results are presented to show the effectiveness.

This paper proposes a step-up/down inverter by using the BuIBB converter, which is innovatively studied.

WE well remember how a speaker at a conference held in 1935 to discuss the organization of research in relation to the needs of industry electrified his audience by suggesting that it was quite fantastic to produce engines for military aeroplanes designed to have a service life of thousands of hours. It would be far better, and more realistic, he argued, to face the fact that the rate of casualties in wartime would be such that any individual engine could only have a life of a few hours—or a few hundred hours at most. If the engines were designed on this basis and those which survived the perils of war automatically withdrawn and scrapped when the end of the short life for which they were designed was nearing it would put an entirely new conception on the whole theory of engine design. Every part could be very much more highly stressed, the power stepped up to undreamed‐of heights and in consequence the Royal Air Force equipped with aeroplanes of infinitely higher performance.

1. The Managing Director of Diners Club International has sent a ‘personal invitation to join and to enjoy all the privileges of membership for six months, without obligation and save the £15 enrolment fee’ to:

To obtain the best moisture‐proof and most reliable protective coating for an amorphous silicon image sensor (A4 documents), three methods of coating and patterning processes and 15 types of resin classified into five kinds of materials were evaluated. Through this study, a screen‐printing method using silicone resin material cured under conditions of 150°C for 60 minutes to form a 60 µm thick protective coating film was selected because of the simplicity of its fabrication process compared with the other two methods. The a‐Si photodiodes were tested under conditions of 121°C‐2 atm. for 300 hours, −30°C to 100°C for 350 cycles and 85°C for 500 hours, and their characteristics were not negatively affected.

An experimental study has been conducted to model and optimize wire electric discharge machining (WEDM) process parameters such as pulse-on time, pulse-off time, servo voltage and peak current for response characteristics during machining of Nimonic 75 alloy.

The response surface methodology (RSM)-based Box–Behnken's design has been employed for experimental investigation. RSM is used for developing quadratic regression models for selected response variables i.e. material removal efficiency and kerf width. To validate the model, confirmation experiments have been performed. The multi-response optimization has been done using desirability function approach.

Through analysis of variation, the percent contribution of process parameters on the response characteristics has been found. Pulse-off time is the most significant parameter affecting the kerf width and material removal efficiency followed by pulse-on time. The quadratic regression models have been developed for prediction of selected response variables. An attempt has been made to optimize the WEDM parameters for material removal efficiency and kerf width. The recommended process parameter setting for maximum material removal efficiency and minimum kerf width have been found to be pulse-on time = 0.6 µs, pulse-off time = 14 µs, servo voltage = 25 V and peak current = 200 A.

The “kerf width” is an important response variable for maintaining dimensional accuracy of the machined component, but has not been given due attention by the researchers. In the present work, the developed regression model for “kerf width” can be used in estimating wire offset setting and thereby getting a dimensionally accurate product. The optimum process parameters obtained in WEDM of Nimonic 75 alloy will contribute in database of machining. The outcome of this study would be added to scare database of the machining of Nimonic 75 alloy and also would be extremely useful for making the technology charts for WEDM.

High school completion is one of the strongest predictors of health and well-being. There is increased public attention on the challenges faced by young people of color and educational achievement. In particular, young men of color must navigate myriad stressors which often undermine their mental health, as well as their academic performance, including likelihood of graduation from high school that fare worse in academic outcomes than their female counterparts. The purpose of this paper is to examine the role of Step-Up, a positive youth development and mental health promotion program, created in collaboration with young people of color on their high school achievement as measured by grade point average (GPA).

This exploratory pre-post study employed multivariate analysis of data drawn from a sample of 212 youth of color to examine student’s GPA before their involvement in Step-Up and the number of Step-Up groups they attend in the first year could improve their high school achievement.

Results revealed an association between students participation in Step-Up, specifically having at least ten life skills group contacts, and significant increases in GPA.

High school achievement is measured by GPA, which might not be a clear indication of achievement since grades are not truly comparable across schools. The exploratory pre-post research design of this study, and the lack of control group, limits any references to causality but the descriptive changes in GPA demonstrate a statistical significance of Step-Up group participation and improved high school achievement. A potential next step is to design an experimental study that includes psychosocial and developmental mechanisms while examining the treatment effect of Step-Up vs students receiving standard of care.

Programs that aid young people of color in increasing their GPA should acknowledge the multitude of stressors that youth in urban environments encounter by creating interventions targeting multiple ecological contexts. These preliminary analyses suggest how programmatic supports that are collaboratively designed with youth, such as Step-Up, may yield promising results in improving young people of color high school achievement.

To better serve adolescents experiencing serious academic and behavioral health challenges, there needs to be programs that offer intensive, short-term mental health support in school settings. Given the widespread risk factors that adolescents and particularly young men of color are facing, Step-Up is informed by both the developmental assets framework and the social development model and aims to provide youth with opportunities for prosocial interactions and additional resources to combat multiple stressors. Since successful completion of high school is associated with better outcomes as young people transition to adulthood, programs that are developmentally timed to allow for an optimal protective factor during the high school years is necessary.

This research contributes to the knowledge base of the importance of providing mental health supports in school settings and may contribute to studies examining the academic achievement of young people of color in school settings.

Stress has been a common phenomenon among the working professionals. The stress has been known to affect the job satisfaction level, health outcomes, affect burnout through the physiological, emotional, behavioral and cognitive processes resulting in to low performance. This study aims to identify the factors determining organizational stress among women workers in the garment industry in India and to develop and validate a contextual scale for organizational stress among women workers in the garment industry in India.

This study consisted of women workers who were employed in garment manufacturing companies. The data has been collected through a structured questionnaire, which identifies the factors leading to stress. The respondents of the study included women workers employed in the garment manufacturing units in and around Bangalore. An exploratory factor analysis was conducted and the model fit was tested using confirmatory factor analysis.

The measurement scale for the organization stress of women workers in the garment industry was found to be highly reliable and valid for conducting the study in any Indian garment industry. The analysis identified the factors as follows: job-related factor, organization-related factor, social factor and personal factor.

Due to limited access to the population, which is the women workers, the authors have not been able to collect a large sample data. The sample size is the limitation of the study.

Organizational stress have has been shown to have a detrimental effect on the health and well-being of employees. Organizations need to step up their effort to integrate emotional well-being, conducive work environment, workloads and job responsibilities, social connectedness and job satisfaction with their efforts to support the physical health and mental health of the workers.

The study is one of its kind with a focus on women workers in the garment industry in India. The study highlights the factors that result in stress among women workers who have not been studied in past research studies. The strategies to cope with organizational stress in such a work requirement is different and very challenging, making it unique for practitioners.

The purpose of this paper is to present the Switched Inductor Z-Source Inverter (SLZSI) topology for three-phase on-line uninterruptible power supply (UPS) by employing third harmonic injected maximum constant boost pulse width modulation (PWM) control. Conventional UPS consists of step-up transformer or boost chopper along with voltage source inverter (VSI) which reduces the efficiency and increases energy conversion cost. The proposed three-phase UPS by using SLZSI has the voltage boost capability through shoot through zero state which is not available in traditional VSI and current source inverter.

Performance of three-phase on-line UPS based on ZLZSI by using third harmonic injected maximum constant boost PWM control is analyzed and evaluated in MATLAB/Simulink software and the results are compared with Z-source inverter (ZSI) fed UPS. Experimental results are presented for the validation of the simulation and theoretical analysis.

The output voltages, currents, THD values, voltage stress and efficiencies for different loading condition are determined and compared with the theoretical values and UPS with ZSI. The experimental results validate the theoretical and simulation results.

Compared with the traditional ZSI, the SLZSI provides high-voltage boost inversion ability with a very short shoot through zero state. This proposed UPS by using SLZSI increases the efficiency with less number of components, reduces the harmonics, increases the voltage gain and reduces the voltage stress.