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Aero-engine components endure combined high and low cycle fatigue (CCF) loading during service, which has attracted more research attention in recent years. This study aims to construct a new framework for the prediction of probabilistic fatigue life and reliability evaluation of an aero-engine turbine shaft under CCF loading if considering the material uncertainty.

To study the CCF failure of the aero-engine turbine shaft, a CCF test is carried out. An improved damage accumulation model is first introduced to predict the CCF life and present high prediction accuracy in the CCF loading situation based on the test. Then, the probabilistic fatigue life of the turbine shaft is predicted based on the finite element analysis and Monte Carlo analysis, where the material uncertainty is taken into account. At last, the reliability evaluation of the turbine shaft is conducted by stress-strength interference models based on an improved damage accumulation model.

The results indicate that predictions agree well with the tested data. The improved damage accumulation model can accurately predict the CCF life because of interaction damage between low cycle fatigue loading and high cycle fatigue loading. As a result, a framework is available for accurate probabilistic fatigue life prediction and reliability evaluation.

The proposed framework and the presented testing in this study show high efficiency on probabilistic CCF fatigue life prediction and can provide technical support for fatigue optimization of the turbine shaft.

The novelty of this work is that CCF loading and material uncertainty are considered in probabilistic fatigue life prediction.

The auto industry in the USA is facing tremendous challenges – plunging demands due to economic downturn, the gloomy trend in technology development, and fierce global competition. This article aims to examine the challenges of supply chain management and to propose a triple‐C (cease‐control‐combine) remedy for the North American auto industry's supply chain management.

The authors applied management theories, collected information from managers at different levels of the auto industry's supply chain management, and developed a novel theoretical model of sustainability in supply chain management for the auto industry.

It is argued that outsourcing to low cost countries – the current supply chain strategy – is not only unsustainable but also irresponsible for the auto industry and society. A triple‐C (cease‐control‐combine) remedy is proposed for the auto industry's supply chain management.

The proposed triple‐C strategy will save the auto industry money in R&D investment, reduce quality cost and inventory waste, help the industry go through the volatile economy, and achieve sustainable development. With close relationships and strong supports from suppliers, the industry can speed up technology development, introduce new gas efficiency models quickly, and become less dependent on gas price. Finally, the triple‐C strategy will help the industry keep jobs and generate new jobs in the USA. These activities lead to public support and restored corporate image.

The current business environment is analyzed, problems of current supply chain strategy discussed, and a new supply chain strategy remedy for the North American auto industry proposed.

The COVID-19 pandemic has caused significant mortality and morbidity worldwide. However, the role of dietary patterns as a potential risk factor for COVID-19 has not been well established, especially in studies with large samples. Therefore, this study aims to identify and evaluate the association between major dietary patterns and COVID-19 among adults from Iran.

In this cross-sectional study, the authors included 9,189 participants aged 20–70 who participated in the Yazd Health Study (YaHS) and Taghzieh Mardom-e-Yazd study (TAMIZ). They used factor analysis to extract dietary patterns based on a food frequency questionnaire (FFQ). Then, they assessed the relationship between these dietary patterns and the odds of COVID-19.

This study identified two major dietary patterns: “high protein and high fiber” and “transitional”. Participants in the highest tertile of the “high protein and high fiber” dietary pattern, which included vegetables, fruits, dairy and various kinds of meats such as red meat, fish and poultry, had a lower odds of COVID-19 compared with those in the lowest tertile. However, the “transitional” dietary pattern did not affect the risk of COVID-19.

In conclusion, a “high protein, high fiber” diet may lower the odds of COVID-19. This study suggests that dietary patterns may influence the severity and spread of future similar pandemics.

The purpose of this study was to prepare carboxylated attapulgite (APT-COOH) and then be used as one of the ligands to prepare metal organic framework (MOF) hybrid materials to reduce the cost of MOF materials and improve the dispersed condition of APT. And then the materials were used to enrich anionic dye Congo red from aqueous solution.

The MOF hybrid materials were designed by means of facile reflux method rather than hydrothermal method, characterized by Thermogravimetric Analysis (TGA), Fourier Transform Infrared (FTIR) Spectrometer and pore structure. The dispersed degree of APT-COOH in the MOF materials was validated according to adsorption efficiency for Congo red.

Due to introduction of APT-COOH, the microenvironment of the MOF materials changed, leading to different adsorption behaviors. Compared to the MOF material without APT-COOH, the adsorption capacities of the hybridized MOF materials with different amounts of APT-COOH introduced increased by 4.58% and 15.55%, respectively, as the initial concentration of Congo red solution of 300 mg/L. Meantime, hybridized MOF materials were suitable to remove Congo red with low concentration, while the MOF material without APT-COOH was appropriate to enrich Congo red with high concentration.

The microstructure of MOF hybrid materials in detail is the further and future investigation.

This study will provide a method to reduce the cost of MOF materials and a theoretical support to treat anionic dyes from aqueous solution.

APT-COOH was prepared and used as one of the ligands to synthesize MOF material to improve the dispersed degree of APT-COOH and reduce the cost of the MOF materials. The adsorption efficiency was greatly enhanced with low concentration of Congo red solution, and the results indicated that hydrogen bonding, electrostatic interaction, and p-p conjugation were involved in the adsorption process. The prepared MOFs materials exhibited excellent adsorption efficiency, which made the present materials highly promising and potentially useful in practical application as adsorbents to enrich anionic dyes such as Congo red from aqueous solution.

The purpose of this paper is to determine the key ingredients of Six Sigma in order to grasp and understand its essential characteristics and then identify suitable ingredients and complements in consideration of vision, strategies, capability, and circumstance of a company.

The study outlines the range of research in Korean enterprises, suppliers, and SMEs. Potential ingredients collected from previous studies about critical success factors, ingredients of Six Sigma and TQM, and criteria of quality awards (Malcolm Baldrige National Quality Award (MBNQA), European Foundation for Quality Management (EFQM) Award, Deming Prize, Korean National Quality Award) are classified into 11 categories based on Six Sigma expert opinions and affinity analysis. Also, questionnaires are surveyed from champions, master black belts and black belts in 90 Korean companies that have more than three years of experience in implementing Six Sigma. Statistical analysis with factor analysis and hypothesis testing has been done to select the key ingredients and to find the differences among the diverse types of companies.

By using factor analysis, three main factors are derived for each category respectively, and consequently 30 factors in 11 categories are concluded as the key ingredients of Six Sigma in Korean companies. There is a significant difference in importance of Six Sigma key ingredients according to company size, business type, and implementation phase.

A study may be conducted to identify Six Sigma success factors according to corporate characteristics from key ingredients identified in this study in future.

The paper investigates the key ingredients of Six Sigma based on a survey of diverse sizes, industries, and implementation phases of Korean companies. Compared with other studies conducted by empirical methods, the survey data are statistically analysed and the evaluation results are represented as quantitative indicators.

In this paper, we draw from our own empirical data on worker organizing and identify important concepts that bridge social movement (SM) and industrial relations (IR) theory. In a context of traditional union decline and a surge of alternative types of worker mobilization, we apply SM and IR concepts related to the mobilizing structures and culture to cases of labor organizing via worker centers and community–labor alliances in the United States and China. From an analytical perspective, we argue that the field of SMs and IR can both benefit from this type of cross-discipline theorization.

The Department of Homeland Security (DHS) states in 2018 that safeguarding “civil liberties is critical” to their official duties. The Office for Civil Rights and Civil Liberties within DHS, as its website explains,

reviews and assesses complaints from the public in areas such as: physical or other abuse; discrimination based on race, ethnicity, national origin, religion, gender, sexual orientation, or disability; inappropriate conditions of confinement; infringements of free speech; violation of right to due process … and any other civil rights or civil liberties violation related to a Department program or activity.

My chapter tracks the centrality of deportability in shaping the civil liberties and rights that DHS is tasked with enforcing. Over the course of the twentieth century, people on US soil saw an expanding list of civil liberties and civil rights. Important scholarship concentrates on the role of the courts, state and federal governments, advocacy groups, social movements, and foreign policy driving these constitutional and cultural changes. For instance, the scholarship illustrates that coming out of World War I, the US Supreme Court ruled that the First Amendment did not protect something the Justices labeled “irresponsible speech.” The Supreme Court soon changed course, opening up an era ever since of more robust First Amendment rights. What has not been undertaken in the literature is an examination of the relationship of deportability to the sweep of civil liberties and civil rights. Starting in the second decade of the twentieth century, federal immigration policymakers began multiplying types of immigration statuses. A century later, among many others, there is the H2A status for temporary low-wage workers, the H2B for skilled labor, and permanent residents with green cards. The deportability of each status constrains access to certain liberties and rights. Thus, in 2016, when people from the Office for Civil Rights and Civil Liberties within DHS act, they are not enforcing a uniform body of rights and liberties that applies equally to citizens and immigrants, or even within the large category of immigrants. Instead, they do so within a complicated matrix of liberties and rights attenuated by deportability, which has been shaped by the history of the twentieth century.

The purpose of this study was to determine the effectiveness of a Qigong program on older adults in the Thai community suffering from mild to moderate depression.

A randomized controlled trial study was conducted in a public health service (PHS) center setting. Sixty-six older adults aged 60–90 years with mild to moderate depressive symptoms measured by the Thai Geriatric Depression Scale (TGDS: scores 13–24) were recruited and randomly allocated into two groups. The subjective sleep quality was assessed using the Thai version of the Pittsburgh Sleep Quality Index (TPSQI). The Qigong program group was given 12 weeks of Qigong training including three sessions per week, while the control group followed normal PHS activities (singing and praying). The outcome measure was the change in the TGDS from baseline to 12 weeks.

Participants in the Qigong program group had a significantly improved TPSQI global score (p < 0.001), subjective sleep quality (p < 0.001), and sleep latency (p < 0.05) after 12 weeks of intervention, while those in the control group showed no significant difference in sleep quality. Compared with the control group, the Qigong program group reported significantly better sleep quality throughout the 12-week period. The prevalence of poor sleep quality in this population was 82 percent.

This study confirmed that the Qigong program could improve sleep quality in older adults with mild to moderate depressive symptoms as the Qigong program conferred more significant improvements than the usual program.

Institutional actors are critical allies for grassroots movements, but few studies have examined their effects and variations within the non-democratic context. This chapter argues that while institutional allies are heavily constrained and unlikely to give open endorsement to grassroot activists, some institutional activists indirectly facilitate movement mobilization and favorable outcomes in the process of advancing their own political agendas. Drawing upon in-depth interviews conducted in 2008 and 2012, I illustrate this argument by examining the Anti-PX Movement – a landmark grassroots environmental movement against a chemical plant – in Xiamen, China. I find that the environmental institutional actors were constrained and divided, yet some still fostered opportunities for movement mobilization and in turn exploited the opportunity created by the protesters to pursue their policy interests, thus facilitating positive movement outcomes. As long as the claims are not politically subversive to the authoritarian rule, this type of tacit and tactical interaction between institutional activists within the state and grassroot activists on the street is conducive to promoting progressive policy changes.

Though the circular economy (CE) is a current buzzword, this still lacks a precise definition. In the absence of a clear notion of what that term includes, actions taken by the government and companies may not be well informed. In particular, those actions need to consider what people mean when people talk about the CE, either to refocus people's decisions or to undertake a more effective communications strategy.

Since people voice people's opinions mainly through social media nowadays, special attention has to be paid to discussions on those media. In this paper, the authors focus on Twitter as a popular social platform to deliver one's thoughts quickly and fast. The authors' research aim is to get the perceptions of people about the CE. After collecting more than 100,000 tweets over 16 weeks, the authors analyse those tweets to understand the public discussion about the CE. The authors conduct a frequency analysis of the most recurring words, including the words' association with other words in the same context and categorise them into a set of topics.

The authors show that the discussion focuses on the usage of resources and materials that heavily endanger sustainability, i.e. carbon and plastic and the harmful habit of wasting. On the other hand, the two most common good practices associated with the CE and sustainability emerge as recycling and reuse (the latter being mentioned far less). Also, the business side of the CE appears to be relevant.

The outcome of this analysis can drive suitable communication strategies by which companies and governments interested in the development of the CE can understand what is actually discussed on social media and call for the attention.

This paper addresses the lack of a standard definition the authors highlighted in the Introduction. The results confirm that people understand CE by looking both at CE's constituent activities and CE's expected consequences, namely the reduction of waste, the transition to a green economy free of plastic and other pollutants and the improvement of the world climate.