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Owing to the toxicity, biodegradability, and cost of most corrosion inhibitors, research attention is now focused on the development of environmentally benign, biodegradable, cheap, and efficient options. In consideration of these facts, chrysin, a phytocompound of Populus tomentosa (Chinese white poplar) has been isolated and investigated for its anticorrosion abilities on carbon steel in a mixed acid and chloride system. This highlights the main purpose of the study.

Chrysin was isolated from Populus tomentosa using column chromatography and characterized using Fourier Transform Infrared Spectroscopy and Nuclear Magnetic Resonance Spectroscopy. The investigations are outlined based on theory (Fukui indices, condensed density functional theory and molecular dynamic simulation) and experiments (electrochemical, gravimetry and surface morphology examinations).

Theoretical evaluations permitted the description of the adsorption characteristics, and molecular interactions and orientations of chrysin on Fe substrate. The interaction energy for protonated and neutral chrysin on Fe (110) were −149.10 kcal/mol and −143.28 kcal/mol, respectively. Moreover, experimental investigations showed that chrysin is a potent mixed-type corrosion inhibitor for steel, whose effectiveness depends on its surrounding temperature and concentration. The optimum inhibition efficiency of 78.7% after 24 h for 1 g/L chrysin at 298 K indicates that the performance of chrysin, as a pure compound, compares favorably with other phytocompounds and plant extracts investigated under similar conditions. However, the inhibition efficiency decreased to 62.5% and 51.8% at 318 K after 48 h and 72 h, respectively.

The novelty of this study relies on the usage of a pure compound in corrosion suppression investigation, thus eliminating the unknown influences obtainable by the presence of multi-phytocompounds in plant extracts, thereby advancing the commercialization of bio-based corrosion inhibitors.

The purpose of this study is to design a radio altimeter antenna whose production process is facilitated and can work with multiple-input multiple-output (MIMO) properties to provide space gain on the aircraft.

To create an easy-to-produce MIMO, a two-storied structure consisting of a reflector and a top antenna was designed. The dimensions of the reflector were prevented to get smaller to supply easy production. The unit cell nearly with the same dimensions of a lower frequency was protected through the original cell design. The co-planar structure with the use of a via connection was modified and a structure was achieved with no need to via for easy production, too. Finally, the antennas were placed side by side and the distance between them was optimized to achieve a MIMO operation.

As a result, an easy-to-produce, compact and successful radio altimeter antenna was obtained with high antenna parameters such as 10.14 dBi gain and 10.55 dBi directivity, and the conical pattern along with proper MIMO features, through original reflector surface and top antenna system.

Since radio altimeter antennas require high radiation properties, the microstrip antenna structure is generally used in literature. This paper contributes by presenting the radio altimeter application with antenna-reflective structure participation. The technical solutions were developed during the design, focusing on an easy manufacturing process for both the reflective surface and the upper antenna. Also, the combination of International Telecommunication Union’s recommended features that require high antenna properties was achieved, which is challenging to reach. In addition, by operating the antenna as a successful MIMO, two goals of easy production and space gain on aircraft have been attained at the same time.

This paper aims to explore the impact of social segregation and exclusionary workplace hazing during lunch breaks on newcomers’ relational quality during the early socialisation phase.

This study draws on data from a qualitative study based on semi-structured interviews with recently employed nurses (n = 19) and nursing students (n = 42) about their workplace hazing experiences. The data was analysed using reflexive thematic analysis.

The analysis revealed two main themes: “feeling isolated” and “justifying self-exclusion.” Newcomers reported feeling humiliated when subjected to exclusionary hazing by experienced colleagues, leading to feelings of alienation and impacting their relationships with their new colleagues. Newcomers tended to distance themselves in various ways and justified this behaviour as a means of self-care.

This paper adds to the limited knowledge about the effects of newcomers’ exposure to workplace hazing during their early socialisation. It provides a relational perspective on the consequences of workplace hazing and explains how the social context influences the normative expectations of newcomers.

The present work involves analytical and experimental investigation of sloshing in a two-dimensional rectangular tank including the effect of porous baffles to control and/or reduce the wave motion in the sloshing tank. The purpose of this study is to assess the analytical solutions of the drag coefficient effect on porous baffles performance to track free surface motion variation in the sloshing tank by comparison with experimental shake table tests under a range of sway excitation.

The linear second-order ordinary differential equations for liquid sloshing in the rectangular tank were solved using Newmark’s beta method and obtained the analytical solutions for liquid sloshing with dual vertical porous baffles of full submergence depths in a sway-oscillated rectangular tank following the methodology similar to Warnitchai and Pinkaew (1998) and Tait (2008).

The porous baffles significantly reduce wave elevation in the varying filled levels of the tank compared to the baffle-free tank under the range of excitation frequencies. It is observed that the Reynolds number-dependent drag coefficient for porous baffles in the tank can significantly reduce the sloshing elevations and is found to be effective to achieve higher damping compared to the porosity-dependent drag coefficient for porous baffles in the sloshing tank. The analytical model’s response to free surface elevation variations in the sloshing tank was compared with the experiment’s test results. The analytical results matched with shake table test results with a quantitative difference near the first resonant frequency.

The scope of the study is limited to porous baffles performance under range sway motion and three different filling levels in the tank. The porous baffle performance includes Reynolds number dependent drag coefficient to explore the damping effect in the sloshing tank.

The porous baffles with low-level porosities in the sloshing tank have many engineering applications where the first resonant mode of sloshing in the tank is more important. The porous baffle drag coefficient is an important parameter to study the baffle’s damping effect in sloshing tanks. Hence, obtained analytical solution for liquid sloshing in the rectangular tank with Reynolds number as well as porosity-dependent drag coefficient (model 1) and porosity-dependent drag coefficient porous baffles (model 2) performance is discussed. The model’s test results were validated using a series of shake table sloshing experiments for three fill levels in the tank with sway motion at various excitation frequencies covering the first four sloshing resonant modes.

The anomaly detection task for oil and gas pipelines based on acoustic signals faces issues such as background noise coverage, lack of effective features, and small sample sizes, resulting in low fault identification accuracy and slow efficiency. The purpose of this paper is to study an accurate and efficient method of pipeline anomaly detection.

First, to address the impact of background noise on the accuracy of anomaly signals, the adaptive multi-threshold center frequency variational mode decomposition method(AMTCF-VMD) method is used to eliminate strong noise in pipeline signals. Secondly, to address the strong data dependency and loss of local features in the Swin Transformer network, a Hybrid Pyramid ConvNet network with an Agent Attention mechanism is proposed. This compensates for the limitations of CNN’s receptive field and enhances the Swin Transformer’s global contextual feature representation capabilities. Thirdly, to address the sparsity and imbalance of anomaly samples, the SpecAugment and Scaper methods are integrated to enhance the model’s generalization ability.

In the pipeline anomaly audio and environmental datasets such as ESC-50, the AMTCF-VMD method shows more significant denoising effects compared to wavelet packet decomposition and EMD methods. Additionally, the model achieved 98.7% accuracy on the preprocessed anomaly audio dataset and 99.0% on the ESC-50 dataset.

This paper innovatively proposes and combines the AMTCF-VMD preprocessing method with the Agent-SwinPyramidNet model, addressing noise interference and low accuracy issues in pipeline anomaly detection, and providing strong support for oil and gas pipeline anomaly recognition tasks in high-noise environments.

Taking the lens of a cue diagnosticity framework and affective primacy theory, this study aims to examine the relative effects of cognitive and affective country image on consumer cognitive judgement, affective evaluation and behavioural tendency in one integrated model. It also explores how the direct effects may vary with the intra-valence nature (ambivalent vs. univalent) of cognition-affect.

The proposed research model was tested using data from a large Chinese sample and consumer responses to products from four countries − the USA, Japan, Brazil and India.

The results show that the relative effects of cognitive and affective country image are complex and differ by the intra-valence nature of cognition-affect. On a general level, cognitive and affective country image exert equal influence on affective evaluation and behavioural tendency. In contrast, cognitive country image demonstrates a more prominent effect than affective country image on cognitive judgement. Compared with univalent, ambivalent cognition-affect strengthens the positive impact of affective country image but does not significantly alter the positive impact of cognitive country image on consumer reactions.

This research contributes to the ongoing debate regarding implications of two focal aspects of macro country image by revealing their relative importance in an integrated framework and enriches country-of-origin research through unveiling the uni/ambivalent cognition-affect as a moderator of the relationship between cognitive/affective country image and consumer reactions. The research findings provide implications as to whether and when marketing strategies should focus on leveraging positive (negative) cognitive or affective country image.

This work measures the performance characteristics of a hemispherical resonator gyroscope (HRG) and compares it with a numerical model.

This work we explore the optical and piezoelectric measurement methods to determine the resonant frequency of HRG. These experimental results are compared with their numerically obtained values. To explore the performance characteristics, the effect of varying actuation voltages on the sense mode displacement and the piezoelectric sensor output was studied in the absence of input angular rate. The structure was then subjected to range of angular rate signals, at a constant actuation voltage and the corresponding sensor response was analysed.

Experimental values of the resonant frequencies in drive and sense modes are found to be within 8% of the numerical results. The sensor output depicts a quadratic dependency on the applied angular rate, which is synchronous with the governing equations of the HRG. The experimental output is within 12% of that obtained numerically. The sensor is found to resolve upto 0.24 rad/s.

This work presents an in-house developed inexpensive measurement setup for static and dynamic characterization of mesoscale MEMS gyroscopes. The measurement setup can also be modified accordingly for measurement of other MEMS-based devices.

As families engage in entrepreneurship, particularly in developing economies, women's engagement in such activities is subject to the traditional cultures, norms and values of the communities to which they belong. This paper aims to investigate how the socio-cultural context influences women's entrepreneurship as women engage in “family entrepreneuring”.

The study draws on an inductive qualitative approach to explore how multiple cultural, social and economic contexts encourage women's entrepreneurship and, thus, position them at the centre of family entrepreneuring within this community. Using snowballing techniques, we analyse narratives from 51 women entrepreneurs, generated through semi-structured interviews, to reveal key insights into the practice of family entrepreneuring.

The findings reveal the complex socio-cultural context within the “Adja” community, where polygamy, a traditional and cultural practice, enables the transfer of culturally and socially embedded informal knowledge. The study explains how women's entrepreneuring activities are supported by informal in-family apprenticeships, resulting in family members learning specific skills while also experiencing the feeling of belonging to the family. Showcasing the heterogeneity of contexts, particularly those found in Africa, this study challenges the normative view within the Global North and the dominance of the “heroic male” in entrepreneurship by showcasing how women (especially matriarchs) are significant actors in training other women, co-wives, daughters and relatives in family entrepreneuring.

Thus, this study contributes to the extant literature on family entrepreneuring by revealing an unusual case of women from polygamous families becoming the focal actors in family entrepreneuring activity and challenging the culturally ascribed gender roles to evolve into the breadwinners in their households, as well as focusing on how this process is driven by endogenous knowledge exchange.

The paper investigates how the engagement of a group of actors (the volunteers), previously unexplored in service ecosystems literature, contributes to generating new co-creation activities and well-being outcomes in the healthcare service ecosystem (HSE). Moreover, the study analyses how the provision and integration of volunteers’ resources help to explain the HSE self-adjustment favouring the re-humanisation of service.

The article zooms in on the volunteers’ activities in an HSE. A qualitative approach is adopted, and an empirical investigation is grounded in data gathered from Kids Kicking Cancer (KKC) Italia, a volunteer association operating in the paediatric oncology ward of Italian hospitals. Data are collected and triangulated through in-depth interviews, volunteers’ diaries and observations. The analysis is conducted by adopting an interpretative thematic analysis technique.

The study provides a conceptual framework explaining how volunteers’ value co-creation activities influence the HSE’s self-adjustment by leading to a re-humanisation of services. The paper also contributes to the state of knowledge by identifying seven categories of volunteers’ value co-creation activities, two of which are completely new in the literature (co-responsibility and empowerment).

The paper contributes to the service research literature by identifying empirically grounded value co-creation activities extending the understanding of self-adjustment and re-humanisation of the service ecosystem.