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The paper aims to improve the radiation-proof capability of the self-designed mobile robot with a 7-DOF manipulator, enabling the long-playing inspection and intervention under high-dose radiation environment. In this context, gamma-ray irradiation test for electronic components and specific hardness design have also been specifically presented and discussed.

The study’s hardness design mainly focuses on shielding protection, distance protection and time protection. Irradiation test is first carried out to investigate irradiation resistance of each electronic module. Then, modular deployment and shielding calculation are completed for the point-type nuclear accidents, respectively, to achieve a robust anti-radiation design scheme. Finally, the field experiment is conducted to validate system effectiveness and good mobility, and operational practices are acquired for the realization of time protection.

Coupled with modular redeployment and shielding design, irradiation results illustrate the effectiveness of robotic anti-radiation design. Meanwhile, experiences and reformed measures from the field exercise implement efficient operation and radiological time protection.

Considering the huge risks of high-dose source exposure, the radiation-resistance of the overall system cannot be verified in the field experiment. Fortunately, irradiation test and modular shielding calculation are conducted as a minimal validation.

The proposed anti-radiation design methods and the irradiated results can be applied to many other nuclear vehicles and manipulators for the feasible multi-layer protection and excellent mobility.

A nuclear intervention robot with specific hardness design is presented in detail in this paper. Enlightened by the idea of shielding and distance protection, a large number of electronic modules with multiple types and structures are treated and compared in irradiation experiments, while modular redeployment and retrofitting are completed to reduce irradiated damages. To achieve the effect of time protection, mobility performance and operational practices are discussed and validated in the field experiment based on the mobile system.

This paper aims to research the corrosion behavior of the metal under the disbonded coatings interfered with AC through electrochemical method.

The corrosion behavior of the metal under disbond coating interfered with alternate stray current (AC) was studied by electrochemical methods using the rectangular coating disbonded simulator. The obtained data from electrode potential test, electrochemical impedance spectroscopy (EIS) and polarization curves in simulated soil solution indicated that under the natural corrosion condition, the self-corrosion potential and the corrosion current density of the metal at different depths under disbond coating had obviously changed if there was AC interference.

The self-corrosion potential of the metal at the same depths under disbond coating shifted negatively with the rising of the AC voltage. Under the condition of cathode polarization, there was still obvious potential gradient with the extension of the deep peeling of the coating gap, and the corrosion current density of the test points was minimum, and the protection effect was best when the cathode protection potential was −1.0 V. When the metal was applied with over-protection, the corrosion rate of the metal increased as AC stray current flowing through it increased.

This paper used the rectangular aperture device to study the corrosion behavior of X80 steel under the disbonded coatings through electrochemical methods when the AC stray current interference voltage was 0V, 1V, 5V or 10V and the protection potential was 0V, −0.9V, −1.0V, −1.2V or −1.3V, respectively. There is great significance to the safe operation and long-term service of pipeline steel in soil environment.

The purpose of this investigation was to study these problems and design regional cathodic protection, using numerical simulation. Regional cathodic protection technology is immature at home and abroad. This is reflected in the fact that in gas stations, there are many underground pipelines, which can lead to serious interference and shielding phenomena, and there are many grounding networks that can cause substantial loss of the cathodic protection current.

Based on the above, in this article, first of all, the mathematical model of the buried pipeline cathodic protection potential distribution was established and the control equations solved using the boundary element method. Second, the cathodic shielding effect in pipeline concentration areas, the effect of instrument equipment grounding systems on cathodic protection and the influence of DC stray current on the interference of pipeline corrosion were studied separately using BEASY software. Finally, the BEASY software was used for a regional cathodic protection design for a real gas station.

It was concluded that impressed current used in combination with sacrificial anodes for regional cathodic protection design is often the most economic and effective approach. However, the output current of the auxiliary anode is large with high energy consumption. In consequence, it may be recommended that the station pipelines should be laid on the ground, rather than under it.

It is considered that the results can guide regional cathodic protection design for real-life installations very well.

The purpose of this study is to evaluate the effect of graphene, basalt flakes and their synergy on the corrosion resistance of zinc-rich coatings. As the important heavy-duty anticorrosion coatings, zinc-rich coatings provided cathodic protection for the substrate. However, to ensure cathodic protection, a large number of zinc powder made the penetration resistance known as the weakness of zinc-rich coatings. Therefore, graphene and basalt flakes were introduced into zinc-rich coatings to coordinate its cathodic protection and shielding performance.

Three kinds of coatings were prepared; they were graphene modified zinc-rich coatings, basalt flakes modified zinc-rich coatings and graphene-basalt flakes modified zinc-rich coatings. The anticorrosion behavior of painted steel was studied by using the electrochemical impedance spectroscopy (EIS) technique in chloride solutions. The equivalent circuit methods were used for EIS analysis to obtain the electrode process structure of the coated steel system. Simultaneously, the corrosion resistance of the three coatings was evaluated by water resistance test, salt water resistance test and salt spray test.

The study found that the addition of a small amount of graphene and basalt flakes significantly improved the anticorrosion performance of coatings by enhancing their shielding ability against corrosive media and increasing the resistance of the electrochemical reaction. The modified coatings exhibited higher water resistance, salt water resistance and salt spray resistance. The graphene-basalt flakes modified zinc-rich coatings demonstrated the best anticorrosion effect. The presence of basalt scales and graphene oxide in the coatings significantly reduced the water content and slowed down the water penetration rate in the coatings, thus prolonging the coating life and improving anticorrosion effects. The modification of zinc-rich coatings with graphene and basalt flakes improved the utilization rate of zinc powder and the shielding property of coatings against corrosive media, thus strengthening the protective effect on steel structures and prolonging the service life of anticorrosion coatings.

The significance of developing graphene-basalt flakes modified zinc-rich coatings lies in their potential to offer superior performance in corrosive environments, leading to prolonged service life of metallic structures, reduced maintenance costs and a safer working environment. Furthermore, such coatings can be used in various industrial applications, including bridges, pipelines and offshore structures, among others.

Stainless-steel electromagnetic shielding (EMS) fabrics are widely applied as protective materials against electromagnetic interference (EMI). However, these fabrics primarily shield electromagnetic waves through reflection, which can lead to the formation of resonance effects that severely compromise their protective capabilities and potentially cause secondary electromagnetic pollution in the external environment.

In this paper, carbon nanotube fibers are added via spacing method to replace some stainless-steel fibers to impart absorbing properties to stainless-steel EMS fabric. The shielding effectiveness (SE) of the EMS fabrics across various polarization directions is analyzed. Additionally, a spacing arrangement for the carbon nanotube fibers is designed. The EMS fabric with carbon nanotube fibers is manufactured using a semi-automatic sample loom, and its SE is tested using a small window method test box in both vertical and horizontal polarization directions.

According to the experimental data and electromagnetic theory analysis, it is determined that when the spacing between the carbon nanotube fibers is less than a specific distance, the SE of the stainless-steel EMS fabric significantly improves. The fabric exhibits stable absorbing properties within the tested frequency range, effectively addressing the issue of secondary damage that arises from relying solely on reflective shielding. Conversely, as the spacing between the carbon nanotube fibers exceeds this distance, the SE diminishes. Notably, the SE in the vertical polarization direction is substantially higher than that in the horizontal polarization direction at the same frequency.

This study provides a new path for the development of high-performance EMS fabrics with good wave-absorption characteristics and SE.

This paper, through empirical evidence, presents a framework for exploring how entrepreneurs navigate the challenges of building legitimacy in a digital context. In so doing, this paper goes beyond the seemingly forgone conclusion that legitimacy is important for the entrepreneur's success by focusing on the contextualised mechanisms through which digital legitimacy is built.

Empirical findings are drawn from semi-structured interviews conducted with 21 digital entrepreneurs in Nigeria, a leading example of the West African context and analysed using a phenomenological approach.

The paper shows how digital entrepreneurs in a non-Western context draw on an aspect of legitimation in the digital space, and in particular, highlights three mechanisms via which this takes place, namely: digital shielding, digital curating and digital networking. Presented via an inductive approach, the three mechanisms described in the paper provide a scaffold for thinking about and understanding entrepreneurial legitimacy within a contextual framework, which incorporates institutional, cultural and digital dimensions.

This paper contributes to the literature on digital entrepreneurship by empirically identifying and theoretically elaborating themes that are important for understanding how entrepreneurs navigate the challenges of digital entrepreneurship and build entrepreneurial legitimacy in complex contexts.

The purpose of this study is to investigate the physical, ultraviolet (UV), colour appearance and colour fastness properties of selected fabrics dyed with natural dyes from Daboya and Ntonso communities of Ghana. The study further highlights the rich cultural heritage of traditional dyeing from these two communities. Craftsmen in West Africa especially Ghana, have sustained the traditional dyeing methods to produce textile products for consumers.

In this study, two sample fabrics were purchased from craftsmen at Ntonso and Daboya communities in Ghana. These fabrics were analysed at the laboratory under standard test methods for their physical, UV, colour appearance and colour fastness properties.

Results showed that all the sample fabrics have good UV shielding performance (ratings above 50+). Daboya sample fabrics (dyed with indigo dyes) produced more colour stains than the sample fabrics from Ntonso (dyed with black “kuntunkuni” dyes). The K/S_sum value or colour yield reduced after washing but that alternatively increased the calculated ultraviolet protection factor.

Findings from this study exposed the unique UV performance of dyed traditional fabrics (using natural dyes) from Ntonso and Daboya communities in Ghana. This inspires and enforces the need for craftsmen to improve their production cycle to produce these fabrics in different sizes which provides the necessary UV shielding abilities for consumers in the wake of climate changes.

This study demonstrated that the natural dyeing process at the two communities produced relatively good UV and colour fastness properties of the sample fabrics. These eco-friendly dyeing practices have survived over time to maintain and promote the concept of sustainability within the textile and fashion industry in Ghana.

Traditional public health methods for tracking contagious diseases are increasingly complemented with digital tools, which use data mining, analytics and crowdsourcing to predict disease outbreaks. In recent years, alongside these public health tools, commercial mobile apps such as Sickweather have also been released. Sickweather collects information from across the web, as well as self-reports from users, so that people can see who is sick in their neighborhood. The purpose of this paper is to examine the privacy and surveillance implications of digital disease tracking tools.

The author performed a content and platform analysis of two apps, Sickweather and HealthMap, by using them for three months, taking regular screenshots and keeping a detailed user journal. This analysis was guided by the walkthrough method and a cultural-historical activity theory framework, taking note of imagery and other content, but also the app functionalities, including characteristics of membership, “rules” and parameters of community mobilization and engagement, monetization and moderation. This allowed me to study HealthMap and Sickweather as modes of governance that allow for (and depend upon) certain actions and particular activity systems.

Draw on concepts of network power, the surveillance assemblage, and Deleuze’s control societies, as well as the data gathered from the content and platform analysis, the author argues that disease tracking apps construct disease threat as omnipresent and urgent, compelling users to submit personal information – including sensitive health data – with little oversight or regulation.

Disease tracking mobile apps are growing in popularity yet have received little attention, particularly regarding privacy concerns or the construction of disease risk.

Reports citing excessive CEO compensation continue to make the news with evidence of peer relationships between the CEO and the compensation committee often the center of debate. The compensation committee of the board of directors determines CEO pay and is often comprises CEOs from other companies as well as non-CEOs such as academic, exgovernment, and professional individuals. This study examines the influence of the psychological factor of social comparison over accounting performance measures in a compensation experiment with 176 subjects. The results of this study are consistent with social comparison theory in that CEO director-subjects award greater pay and shield the compensation of the CEO when firm accounting performance is below average. Additionally, we find shielding is mitigated when subjects are informed that the decision of the amount of compensation awarded will be revealed to the public.

Zara et al. (2023) provide novel findings into how psychopathy may develop, showing that early life predictors of poor relationships (e.g. being unwanted before birth) are predictive of psychopathy in adulthood. The authors provide a theoretical interpretation of why psychopathy might develop based on these findings by using an adaptive perspective, suggesting that psychopathy may protect or shield individuals from poor relationships. This commentary aims to critically evaluate and extend this latter suggestion in hopes of fostering further research and clarity on the topic.

After presenting an overview of evolutionary perspectives, a summary and elaboration are presented of the interpretation that psychopathy may be an adaptive response that functions to protect individuals from poor relationships. Then, an additional adaptive interpretation is offered.

Psychopathy describes a collection of traits and behavior that facilitates an approach-oriented and exploitative motivational style that might suggest more than a protective function. When negative or poor relationships are experienced (e.g. being unwanted), it is suggested that psychopathy may begin to develop not just for protection (If I am not loved, I will shield myself from those around me) but to actively orient toward exploitation (If I am not loved, I will exploit those around me).

This commentary hopes to arouse further interest into the theoretical interpretations of why psychopathy may develop that are based on findings of how psychopathy develops. These considerations are consequential for understanding what to target in treatments that aim to meet the specific needs and motivations of individuals with psychopathic traits.