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This study aims to investigate the causes of leakage in radial oil seals under dynamic eccentricity, elucidate the influence of operating parameters on leakage failure and develop methods for predicting and preventing such leakage.

Based on the principle of cam motion and considering viscoelasticity, develops a motion model of the compression and release of the shaft seal and proposes a method to determine its failure. In addition, this study quantifies the leakage gap and formulates a quantitative calculation model to accurately determine the location and shape parameters of the leakage gap.

Leakage gaps predominantly occur during the release phase of the shaft seal. Their presence can be identified by comparing the descending times of the seal and the shaft during this phase. An increase in rotation speed and eccentricity heightens the likelihood of gap formation, with both the dimensions and leakage rate of the gap increasing as these factors escalate. Eccentricity, in particular, has a more pronounced effect on gap formation.

This study clarifies the failure mechanisms of radial oil seals under dynamic eccentricity and introduces a criterion for identifying leakage gaps, providing valuable theoretical guidance for the design and optimization of radial oil seals.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2024-0192/.

Cold-formed steel (CFS) sections are a popular choice for constructing medium and low-rise structures that are engineered to support relatively light loads. An important characteristic of CFS sections is that they are produced without the use of heat during manufacturing. Consequently, it becomes essential to gain a comprehensive understanding in the behavior of CFS sections when exposed to fire or elevated temperatures.

In this study, sections of 1.5 m length and 2 mm thickness were taken and analyzed to find its flexural behavior after heating them for 60 and 90 min. There were two modes of cooling phase which was considered to reach ambient temperature, i.e. air or water respectively. Performance of each sections (C, C with inclined flanges, sigma and Zed) were examined and evaluated at different conditions. Effects of different profiles and lips in the profiles on flexural behavior of CFS sections were investigated fully analytically.

The variation in stiffness among the sections with different lipped profiles was noted between 20.36 and 33.26%, for 60 min water cooling case. For the sections with unlipped profiles, it was between 23.56 and 28.60%. Influence of lip and section profile on reduction in stiffness is marginal. The average reduction in load capacity of sections for 60 min specimens cooled by water was found to be 43.42%. An increase in deflection is observed for the sections in the range of 25–37.23% for 60 min case. This is the critical temperature responsible for reduction in yield strength of material as it substantially increases the material safety margin to be considered for the design. Sections with Zed profile have shown better performance among other types, in terms of its load carrying capacity.

This paper deals with the flexural behavior of Galvanized (GI) based CFS unsymmetric sections at elevated temperature and cooled down to ambient temperature with air or water.

Ciliated microelectromechanical system (MEMS) vector hydrophones pick up sound signals through Wheatstone bridge in cross beam-ciliated microstructures to achieve information transmission. This paper aims to overcome the complexity and variability of the marine environment and achieve accurate location of targets. In this paper, a new method for ocean noise denoising based on improved complete ensemble empirical mode decomposition with adaptive noise combined with wavelet threshold processing method (CEEMDAN-WT) is proposed.

Based on the CEEMDAN-WT method, the signal is decomposed into different intrinsic mode functions (IMFs), and relevant parameters are selected to obtain IMF denoised signals through WT method for the noisy mode components with low sample entropy. The final pure signal is obtained by reconstructing the unprocessed mode components and the denoising component, effectively separating the signal from the wave interference.

The three methods of empirical mode decomposition (EMD), ensemble empirical mode decomposition (EEMD) and CEEMDAN are compared and analyzed by simulation. The simulation results show that the CEEMDAN method has higher signal-to-noise ratio and smaller reconstruction error than EMD and EEMD. The feasibility and practicability of the combined denoising method are verified by indoor and outdoor experiments, and the underwater acoustic experiment data after processing are combined beams. The problem of blurry left and right sides is solved, and the high precision orientation of the target is realized.

This algorithm provides a theoretical basis for MEMS hydrophones to achieve accurate target positioning in the ocean, and can be applied to the hardware design of sonobuoys, which is widely used in various underwater acoustic work.

This paper studies the location-inventory problem (LIP) in pallet pooling systems to improve resource utilization and save logistics costs, which is a new extension of the classical LIP and also an application of the LIP in pallet pooling systems.

A mixed-integer linear programming is established, considering the location problem of pallet pooling centers (PPCs) with multi-level capacity, multi-period inventory management and bi-directional logistics. Owing to the computational complexity of the problem, a hybrid genetic algorithm (GA) is then proposed, where three local searching strategies are designed to improve the problem-solving efficiency. Lastly, numerical experiments are carried out to validate the feasibility of the established model and the efficiency of the proposed algorithm.

The results of numerical experiments show that (1) the proposed model can obtain the integrated optimal solution of the location problem and inventory management, which is better than the two-stage model and the model with single-level capacity; (2) the total cost and network structure are sensitive to the number of PPCs, the unit inventory cost, the proportion of repairable pallets and the fixed transportation cost and (3) the proposed hybrid GA shows good performance in terms of solution quality and computational time.

The established model extends the classical LIP by considering more practical factors, and the proposed algorithm provides support for solving large-scale problems. In addition, this study can also offer valuable decision support for managers in pallet pooling systems.

This qualitative study investigated the relationship between beauty standards and identity in the United States from the perspective of 20 self-identified millennial Black women. During semi-structured virtual interviews, participants defined Black, American, and millennial beauty standards distinctly. American beauty was associated with Eurocentrism and mainstream media representation. Interpretations of a millennial beauty standard were aligned with perceptions of the generation as tolerant and politically conscious. Black American beauty standards embraced the range of hair textures and skin tones present in the African diaspora. While participants were cognizant of the different beauty ideals present, their interaction with beauty standards was ambivalent. Interviewees found beauty knowledge accessible through social media. However, they remain confined to a restrictive beauty standard due to workplace expectations around professionalism. Participants negotiated where and when to express their intracultural beauty ideals but participated in the beauty industry through processes of learning how to care for their hair in its natural state. Even though they have autonomy and flexibility in expressing their cultural styles, personal and professional repercussions are still plausible. Future studies can expand on these findings by exploring perceptions of American beauty standards from a different generation, region, or identity.

Compared to typical brand extension research focusing on functional and symbolic attributes, this paper aims to examine brand extensions based on a brand's primary sensory attributes. Specifically, this paper investigates the interplay between brand equity and primary sensory attributes in shaping consumers' evaluations of brand extensions.

This study investigates the impact of primary or central sensory attributes on brand extension evaluations for brands with differing brand equities. The authors conducted two experiments preceded by seven pretests to develop and validate the stimulus materials. The authors aim to contribute to understanding how sensory and brand-related factors influence consumers' evaluations of brand extensions.

In these experiments, the authors find that a parent brand's central/dominant sensory attribute allows the parent brand to successfully extend into functionally unrelated categories. For example, Dove’s central attribute of touch allows it to extend successfully into categories such as towels and shaving razor. However, it does not perform as well as Irish Spring (known for smell) in categories such as cologne and scented fabric softener, where Irish Spring's central attribute of smell is more relevant. Interestingly, Irish Spring, a lower equity brand, outperforms Dove in smell-related extensions, indicating that sensory attributes can counter the impact of lower brand equity if the sensory attribute is relevant to the extension category.

This study investigates brand extensions based on sensory attributes such as smell and touch instead of typical brand extensions based on functional and symbolic attributes. In particular, the authors examine whether the perceived fit between the parent brand’s dominant sensory attribute and the extended category (i.e. sensory fit) is more important than the parent brand's equity in the evaluation of brand extensions.

This study aims to study the interaction effects between a rectangular supersonic jet with a flat wall computationally using wall length as a parameter. The purpose of this study is to investigate the effect of change in wall length on supersonic core length (SCL) reduction, jet deflection and jet decay behavior.

The design Mach number and aspect ratio at the rectangular exit were 1.8 and 2, respectively. To study the wall length effects on jet-wall interactions, wall length (L_w) was varied as 0.5D_h, 1D_h, 2D_h, 4D_h and 8D_h, where D_h was the hydraulic diameter of the nozzle exit. The flat wall with the matching width of the rectangular exit section of a supersonic nozzle was placed at the nozzle exit such that the supersonic jet grazed past the wall. The studies were carried out at over-expansion [nozzle pressure ratio (NPR) = 4], near optimum expansion (NPR = 6) and under-expansion (NPR = 8) levels.

Results indicated that significant reduction in wall-bounded SCL was noticed in the range of 0.5D_h  ≤  L_w ≤ 1D_h for both over-expansion and under-expansion conditions. At L_w ≥ 4D_h, SCL got enhanced at NPR = 4 and 6 but had a negligible effect at NPR = 8.

Thrust vector control, noise reduction and easy take-off for high-speed aircraft.

The effect of change in flat wall length on interaction characteristics of a rectangular supersonic jet was not studied before in terms of SCL reduction and jet decay behavior.

There has been an explosion of interest in “Equity, Diversity, and Inclusion” (EDI) – also referred to as DEI among other acronyms. On the one hand, this management trend has the potential to draw attention to the ways in which organizational practices and climates can be transformed to have a positive impact on the underrepresentation of women and other marginalized and excluded groups in the workplace. On the other hand, there may be real consequences for women as EDI replaces other concepts such as women's rights, gender equality, affirmative action, employment equity, gender discrimination, etc. This chapter applies a gender lens to the EDI concept and management policy and practice. It juxtaposes EDI's emergence with the lack of progress on gender equality that is observed and measured in many regions of the world and highlights several critiques that may explain this lack of progress. It also identifies what EDI policies and practices need to take into consideration to better address gender inequality in the workplace. Legal approaches are discussed along with a list of potential areas of research on EDI and gender equality to determine the best path forward for making concrete progress on true equality for women in the workplace.

Past research has shown there is a relationship between body image, sexual behavior, and pleasure. However, the majority of this research has centered on heterosexual participants. In this analysis, the author considers how this relationship between body image, sexual behavior, and pleasure may look within women and genderqueer individuals who are all AFAB (assigned female at birth) with 26 out of 30 participants identifying as LGBTQIA+. The author examines perceptions of body size, body hair, and genitals to consider how intersections of social structures – specifically internalized sexism, racism, and misogyny – influence the participants’ experience of sexual interactions. Both resistance and embodiment of traditional gender norms, even as queer women and genderqueer individuals, were examined in these narratives. The majority of the moments where traditional gender norms are examined describe situations when the participants were sexually interacting with cis-gendered men.

Every organization must deal with new challenges such as automation, digitization, or structural transformation, which requires a highly resilient and engaged workforce to stay competitive. Strong leadership in a firm and specific abilities of the leader are necessary to manage uncertainties and to be able to react to certain changes. Various studies regarding organizations and resilience focus on large enterprises, while studies on small- and medium-sized enterprises (SMEs) are lacking. SMEs account for 99.6% of all companies in Austria and are largely run by entrepreneurial owners and their families. Based on transformational theory, the theory of resilience as well as positive psychology, we investigate five SME owners and their personal resilience in an exploratory study. The owners were selected by purposive sampling with the aim to develop a framework with recommended actions for the personal resilience of SME leaders.