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This review aims to give a critical view of the wheel/rail high frequency vibration-induced vibration fatigue in railway bogie.

Vibration fatigue of railway bogie arising from the wheel/rail high frequency vibration has become the main concern of railway operators. Previous reviews usually focused on the formation mechanism of wheel/rail high frequency vibration. This paper thus gives a critical review of the vibration fatigue of railway bogie owing to the short-pitch irregularities-induced high frequency vibration, including a brief introduction of short-pitch irregularities, associated high frequency vibration in railway bogie, typical vibration fatigue failure cases of railway bogie and methodologies used for the assessment of vibration fatigue and research gaps.

The results showed that the resulting excitation frequencies of short-pitch irregularity vary substantially due to different track types and formation mechanisms. The axle box-mounted components are much more vulnerable to vibration fatigue compared with other components. The wheel polygonal wear and rail corrugation-induced high frequency vibration is the main driving force of fatigue failure, and the fatigue crack usually initiates from the defect of the weld seam. Vibration spectrum for attachments of railway bogie defined in the standard underestimates the vibration level arising from the short-pitch irregularities. The current investigations on vibration fatigue mainly focus on the methods to improve the accuracy of fatigue damage assessment, and a systematical design method for vibration fatigue remains a huge gap to improve the survival probability when the rail vehicle is subjected to vibration fatigue.

The research can facilitate the development of a new methodology to improve the fatigue life of railway vehicles when subjected to wheel/rail high frequency vibration.

Brief introduction on the importance and the need for plastic analysis methods were presented in the beginning section of this review. The plastic method for analysis was considered to be the more advanced method of analysis because of its ability to represent the true behaviour of the steel structures. Then in the following section, a literature analysis has been carried out on the previous investigations done on steel plates, steel beams and steel frames by other authors. The behaviour of them under different types of loading were presented and are under the investigation of innovative new analysis methods.

Structure member connections also have the potential for plastic failure. In this study, the authors have highlighted a few topics to be discussed. The three topics in this study are T-end plate connections to a square hollow section, semi-rigid connections and cold-formed steel storage racks with spine bracings using speed-lock connections. Connection is one of the important parts of a structure that ensures the integrity of the structure. Finally, in this technical paper, the authors introduce some topics related to seismic action. Application of the Theory of Plastic Mechanism Control in seismic design is studied in the beginning. At the end, its in-depth application for moment resisting frames-eccentrically braced frames dual systems is investigated.

When this study involves the design of a plastic structure, the design criteria must involve the ultimate load rather than the yield stress. As the steel behaves in the plastic range, it means the capacity of the steel has reached the ultimate load. Ultimate load design and load factor design are the methods in the range of plastic analysis. After the steel capacity has reached beyond the yield stress, it fulfills the requirement in this method. The plastic analysis method offers a consistent and logical approach to structural analysis. It provides an economical solution in terms of steel weight, as the sections designed using this method are smaller compared with elastic design methods.

The plastic method is the primary approach used in the analysis and design of statically indeterminate frame structures.

The proliferation of surveillance-enhancing laws, policies and technologies across African countries deepens the risk of privacy rights breaches, as well as the risks of adverse profiling and social sorting. There is a heightened need for dedicated advocacy and activism to consistently demand accountability and transparency from African states, governments and their allies regarding surveillance. The purpose of this paper is to understand the issue frames that accompany anti-surveillance and privacy advocacy in Ghana and the related implications.

Using a qualitative and interpretivist approach, the author focuses on three different surveillance-oriented incidents/programs in Ghana and analyzes the frames underpinning the related advocacy and narratives of various non-state actors.

Privacy and anti-surveillance advocacy in Ghana tends to be less framed in the context of privacy rights and is more driven by concerns about corruption and value for money. Such pecuniary emphasis is rational per issue salience calculations as it elevates principles of economic probity, transparency and accountability and pursues a high public shock value and resonance.

Economics-centered critiques of surveillance could be counterproductive as they create a low bar for surveillance promoters and sustains a culture of permissible statist intrusions into citizens’ lives once economic virtues are satisfied.

While anti-surveillance and privacy advocacy is budding across African countries, little is known about its nature, frames and modus compared to such advocacy in European and North American settings. To the best of the author’s knowledge, this is likely the first paper or one of the first dedicated fully to anti-surveillance and advocacy in Africa.

This performance autoethnography may or may not be interpreted as a continuation of a conversation regarding the experiences of those with devalued statuses in academic settings. The authors rely on “strange accounting” to consider their experiences in the academy from various standpoints: before and after promotion, before and after leaving academia. While reflecting on our past experiences, we introduce the concept of “everyday precariousness” as a way of explaining the normalization of instability, insecurity, and negative affect that is part of everyday life for those with devalued statuses in academic settings and beyond. Everyday precariousness is an embodied experience for those in vulnerable positions. Normalized exposure to risks, such as discrimination, harassment, bullying, or structural instability, produces an undercurrent of threat that permeates academic culture. Our stories of everyday precariousness span race, ethnicity, class, academic roles, and gender boundaries (among many others). Analyzing these experiences furthers previous work on the uses of strange accounting as well as the dynamics of status silencing. In the final analysis, unresisted and unabated, everyday precariousness and status silencing can lead to institutional failure and resonance disasters.

The basis of safe flight is the management of risks. This paper aims to present a new process-based risk assessment model, with an approach to calculate the risk score.

Since thousands of minor changes occur within ground operations, it is difficult to calculate how much risk these variations will pose. This paper proposes a risk assessment model fed from analysis of ground operation processes using functional resonance analysis method (FRAM) and fuzzy logic.

FRAM is used to detect variations in ground operation. Using the FRAM analysis, it has been revealed how much risk the process steps described in the procedures involve. The risk score was calculated by combining the probability value obtained from the airline’s database and the severity assessment of the expert group in fuzzy logic. The risk level can be monitored dynamically with the transfer of events in the airline’s database to the process-based risk assessment model.

FRAM analysis, which is used to detect function variations before undesirable risk occurs, has brought a proactive approach to risk assessment. The process-based risk assessment model allows the creation of new safety parameter indicators to be followed to reduce the risk level of the function with a high-risk level. The proposed approach can be used for other operational areas in aviation as well.

Framed by nostalgia marketing, this research draws upon lessons from ParticipACTION, a Canadian non-profit health promotion organization, to examine one of their most well-known campaigns, Body Break with ParticipACTION, in order to assess the potential role for nostalgia-based marketing campaigns in sport participation across generational cohorts.

Exploratory sequential mixed methods involving two studies were completed on behalf of ParticipACTION, with the authors developing the research instruments and the collection of the data undertaken by research agencies. Study 1 was the secondary analysis of qualitative data from five focus groups with different demographic compositions that followed a common question guide. Study 2 was a secondary data analysis of a pan-Canadian online survey with a sample (n = 1,475) representative of the overall adult population that assessed awareness of, and attitudes toward, ParticipACTION, Body Break, physical activity and sport participation. Path analysis tested a proposed model that was based on previous research on attitudes, brand and loyalty. Further, multi-group path analyses were conducted to compare younger generations with older ones.

The results provide direction and understanding of the importance of nostalgia in marketing sport participation programs across generational cohorts. For instance, in the four parent-adult focus groups, unaided references as well as frequent and detailed comments regarding Body Break were observed. Similarly, Millennials reported that Body Break was memorable, Canadian and nostalgic, with a mix of positive and negative comments. The importance of nostalgia was supported sequentially via results from the national survey. For example, while 54.1% of the 40–54 age-group associated ParticipACTION positively with Body Break, so did 49.8% of the 25–39-year age group, most of whom were not born when the promotion ran. Further, brand resonance was found to explain 4% more variance in moderate-to-vigorous physical activity (MVPA), the proxy for sport participation, for younger people compared to older people.

Results provide direction to brands, properties and agencies around the use of nostalgia in sport marketing campaigns and sponsorship efforts. For brands seeking to sponsor sport properties to alter their image with potential consumers in a new market, associating with a sport property that many view as nostalgic could improve the impact of the campaign. On the sport property side, event managers and marketers should both identify existing assets that members or fans are nostalgic about, as well as consider building nostalgia into current and new properties they develop.

This research is valuable to the sport marketing and sponsorship literature through several contributions. First, the use of nostalgia marketing, and nostalgia in general, is novel in the sport marketing and sponsorship literature, with future research in nostalgia and sponsorship recommended. Second, the potential to adopt or adapt Body Break to other sport participation and physical activity properties is empirically supported. Finally, the finding that very effective promotions can have a long-lasting effect, both on those who experienced the campaigns as well as younger populations who only heard about it, is notable.

How do radical technological fields become naturalized and taken for granted? This is a fundamental question given both the positive and negative hype surrounding the emergence of many new technologies. In this chapter, we study the emergence of the US nanotechnology field, focusing on uncovering the mechanisms by which leaders of the National Nanotechnology Initiative managed hype and its concomitant legitimacy challenges which threatened the commercial viability of nanotechnology. Drawing on the cultural entrepreneurship literature at the interface of strategy and organization theory, we argue that the construction of a naturalizing frame – a frame that focuses attention and practice on mundane, “rationalized” activity – is key to legitimating a novel and uncertain technological field. Leveraging the insights from our case study, we further develop a staged process model of how a naturalizing frame may be constructed, thereby paving the way for a decrease in hype and the institutionalization of new technologies.

This paper aims to propose a two-stage vibration isolation system for large airborne equipment to isolate aircraft vibration load.

First, the vibration isolation law of the discrete model of large airborne equipment under different damping ratios, stiffness ratios and mass ratios is analyzed, which guides the establishment of a three-dimensional solid model of large airborne equipment. Subsequently, the vibration isolation transfer efficiency is analyzed based on the three-dimensional model of the airborne equipment, and the angular and linear vibration responses of the two-stage vibration isolation system under different frequencies are studied.

Finally, studies have shown that the steady-state angular vibration at the non-resonant frequency changes little. In contrast, the maximum angular vibration at the resonance peak reaches 0.0033 rad, at least 20 times the response at the non-resonant frequency. The linear vibration at the resonant frequency is at least 2.14 times the response at the non-resonant frequency. Obviously, the amplification factor of linear vibration is less than that of angular vibration, and angular vibration has the most significant effect on the internal vibration of airborne equipment.

The two-stage vibration isolation equipment designed in this paper has a positive guiding significance for the vibration isolation design of large airborne equipment.

This study aimed to understand coopetition in the context of Brazilian specialty coffee grower Small and medium enterprises (SMEs), based on the need to differentiate the beans in and outside the farm level, taking into account the stakeholders’ influence.

In this study twenty semistructured interviews were carried out with coffee growers and managers of cooperatives, associations and supporting institutions involving two Brazilian coffee geographical indications. Data were analyzed using a mixed grid composed of qualitative, semantic and categorical factors.

Strategic moves undertaken by coffee growers and stakeholders have shaped the pathway of coopetition among coffee growers, as determinants to frame it as a deliberate or emergent pattern (intentional or unplanned, respectively). Our findings provide evidence that coopetition development among firms is deliberate when influenced by firms’ or stakeholders’ cooperative moves and emergent when influenced by firms’ or stakeholders’ competitive moves.

Although the firm/stakeholder relationship is often approached as a joint wealth creation effort, stakes are not always fairly distributed, so one of the parties may be negatively affected, with consequences for the development of coopetition. Underpinned by a stakeholder-oriented resource-based theoretical lens, this investigation of the development patterns of coopetition linked to the strategic actions undertaken by firms and stakeholders has resonance on competitive advantages.

This study aims to construct a novel maximum power tracking control system for the direct drive permanent magnet synchronous generator (PMSG) of the wind energy conversion system (WECS) to solve the following problems: how to effectively eliminate the system’s model parameter disturbances and speed up the dynamic performance of the system; and how to eliminate harmonics in WECS under different wind speeds.

To obtain the maximum output power of PMSG at WECS under different wind speeds, the following issues should be considered: (1) how to effectively eliminate the system’s model parameter disturbances and speed up the dynamic performance of the system; and (2) how to suppress system harmonics. For Problem 1, adding d–q compensation factors to active disturbance rejection control (ADRC) for the current loop realizes the d–q axis decoupling control, which speeds up the dynamic performance of the system. For Problem 2, the resonant controller is introduced into the ADRC for the current loop to suppress harmonic current in WECS under different wind speeds.

The simulation results demonstrate that the proposed control method is simpler and more reliable than conventional controllers for maximum power tracking.

Compared with traditional controllers, the proposed controller can speed up the dynamic performance of the system and suppress the current harmonic effectively, thus better achieving maximum power tracking.