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The suggested antenna has a switched mechanism among the successive elements of the radiating patch. The purpose of this paper is to develop high gain and less interference at higher frequencies.

The design geometry of the suggested high gain switched beam Yagi-Uda antennas. The constructed antenna has been developed with Rogers Substrate, relative permittivity (ε_r) of 4.4, tangent of loss 0.0009 and with height of 1.6 mm. The proposed antenna has an input impedance of 50, and it is connected to input feed line with 2 mm.

In forthcoming life, the antennas play key role in all the wireless devices, because these devices perform with high gain and high efficacy.

The pivotal principle of this paper is to accomplish the gain as high, high directivity and interference is low at higher frequencies. Therefore, it is more applicable to 5G mobile communications and millimeter wave communications.

Acidization is one of the most important techniques to increase the productivity of crude petroleum oil and gas wells. The effective way for protecting these oil well tubular materials is by using corrosion inhibitors during the acidization process. The present study deals with the evaluation of inhibition effect of ethanolamines on oil well tubular materials of grade N‐80 steel in 15 per cent hydrochloric acid at room temperature with 0‐2 per cent amine concentrations. The amines such as mono, di and triethanolamine were studied for their inhibiting capacity by mass loss method, DC polarization method and AC Impedance method. The inhibitor efficiency increases with increasing concentration of amines. Monoethanolamine is found to be more effective than the other two amines.

Robots are predicted to have a profound impact on the service sector. The emergence of robots has attracted increasing interest from business scholars and practitioners alike. In this article, we undertake a systematic review of the business literature about the impact of service robots on customers and employees with the objective of guiding future research.

We analyzed the literature on service robots as they relate to customers and employees in business journals listed in the Financial Times top 50 journals plus all journals covered in the cross-disciplinary SERVSIG literature alerts.

The analysis of the identified studies yielded multiple observations about the impact of service robots on customers (e.g. overarching frameworks on acceptance and usage of service robots; characteristics of service robots and anthropomorphism; and potential for enhanced and deteriorated service experiences) and service employees (e.g. employee benefits such as reduced routine work, enhanced productivity and job satisfaction; potential negative consequences such as loss of autonomy and a range of negative psychological outcomes; opportunities for human–robot collaboration; job insecurity; and robot-related up-skilling and development requirements). We also conclude that current research on service robots is fragmented, is largely conceptual in nature and focused on the initial adoption stage. We feel that more research is needed to build an overarching theory. In addition, more empirical research is needed, especially on the long(er)-term usage service robots on actual behaviors, the well-being and potential downsides and (ethical) risks for customers and service employees.

Our review focused on the business and service literature. Future work may want to include additional literature streams, including those in computer science, engineering and information systems.

This article is the first to synthesize the business and service literature on the impact of service robots on customers and employees.

Retailers are increasingly considering the introduction of service robots in their stores to support or even replace service staff. Service robots can execute service scripts during the service encounter that can influence customer interactions and the overall experience. While the role of service agents is well documented, more research is needed to understand customer responses to a technology-infused servicescape and to investigate the value of service robots as interaction partners. The purpose of this study is to examine the degree of customer immersion in human-human or human-robot interactions across different stages of the service experience and to understand how immersion affects store visit duration under each condition.

An experimental field study was developed to test the research hypotheses. The study was conducted in a retail store selling premium Italian leather goods with 50 respondents randomly allocated to one of two experimental conditions, interaction with a service robot or interaction with a human sales associate. Participants’ biometrics were collected to measure their immersion in the service encounter and to assess its impact on store visit duration.

The interaction with a service robot increases the level of customer immersion during the service encounter’s welcome and surprise moments. Immersion positively affects visit duration. However, participants exposed to a robot sales associate reported a shorter visit duration as compared to those who interacted with a human sales associate.

This study contributes to the emerging service and retail marketing literature on service robot applications applying a neuroscientific approach to the study of human–robot interactions across different moments of the service encounter. For managers, this study shows the conditions under which service robots can be successfully implemented in retail stores in accordance with the type of task performed and the degree of immersion generated in customers.

This study explores how customers' individual characteristics and perceptions affect acceptance of service robots as a hotel workforce. The Interactive Technology Acceptance Model (iTAM) has inspired us to investigate effects of customers' technological self-efficacy, perceived interactivity, sense of utility, and enjoyment-level of acceptance related to hotel-service robots as staff.

Data were collected from 224 customers via an online questionnaire conducted in the period April–June 2022 by convenience sampling, and then analyzed by using partial least squares – structural equation modeling (PLS-SEM).

The findings show that customers' technological self-efficacy and perceived interactivity with service robots enhances perceived usefulness and perceived enjoyment, serving as functional and emotional value components of service robots. They also demonstrate that robot's interactivity outweighs other robot's value components, such as perceived usefulness and perceived enjoyment for acceptance of service robots as employees in hotels.

While empirically validating the iTAM, this study emphasizes service robot interactivity as the most important aspect for customers' acceptance, and it adds a new perspective regarding the underexplored role of the customer-robot interface. Combining specific dimensions from different technology acceptance models (functional/socio-emotional/relational; utilitarian/hedonic) the study contributes to the service robot literature currently missing a more holistic understanding of consumers' experience and adoption drivers, and it provides managerial guidance on how to successfully implement service robots in hotel environments.

Although cognitive apprenticeship has been widely used in various educational fields, few empirical studies have examined its effectiveness in a workplace context. This study aims to investigate the effects of cognitive apprenticeship on junior doctors’ perceived professional growth in hospitals.

A retrospective questionnaire survey was performed that asked surgeons (n = 87) and physicians (n = 92) to recall how they were instructed by their supervisors during the first five years after graduation from medical school.

The results of multiple regression analyzes showed that all dimensions of cognitive apprenticeship (modeling, coaching, scaffolding, articulation, reflection and exploration) had positive effects on each doctor’s perceived growth, regardless of the type of clinical practice (surgeon vs physician) or the period of supervision. It was also found that physicians experienced significantly more coaching and scaffolding, and opportunities for, articulation and reflection, than surgeons.

Some of the data were collected through snowball sampling, and this study used a retrospective survey in which respondents were asked to recall past experiences.

Clinical supervisors in hospitals should adopt a cognitive apprenticeship model when supervising junior doctors. Surgical supervisors need to be more conscious of the benefits of cognitive apprenticeship.

This study confirmed that the six dimensions of cognitive apprenticeship had positive influences on the perceived growth of junior doctors, regardless of their clinical domains or period of supervision and that clinical domains influence the implementation of cognitive apprenticeship.

The inhibition effect of propargyl alcohol on the acidic corrosion of mild steel in 5 per cent commercial hydrochloric acid was studied at different temperatures by mass loss measurements and polarization studies. Corrosion potential and corrosion current have been calculated in the presence and in the absence of inhibitor. The inhibitor efficiency increases with increase in concentration and it decreases with rise in temperature. The interrelationship between the surface coverage and concentration of the inhibitor was also studied. It has been found that the inhibitor obeys Temkin adsorption isotherm.

Reports on corrosion and microfouling analyses carried out in natural pondwater using mild steel under static condition. Corrosion rates were measured at regular intervals by weight loss and polarization techniques. The corrosion rate obtained by weight loss measurement was found to be less in the biotic system, but corrosion current obtained by polarization studies was higher in the biotic than abiotic system. Surface analysis by x‐ray diffraction indicates that bacteria with organic nutrients inhabited the corrosion to formation of surface film.

The purpose of the paper was to investigate the use of aqueous extract of date palm (Phoenix dactylifera) leaf as a green inhibitor for corrosion of carbon steel in 1M hydrochloric acid (HCl) solution.

Extracts from the date palm were used as the main component of an environmentally friendly corrosion inhibitor for use in HCl pickling processes. Inhibition behavior on carbon steel in HCl was investigated using weight loss measurements, linear and potentiodynamic polarization curves, electrochemical impedance spectroscopy and scanning electron microscopy.

The results show that the extract exhibited good inhibition performance in 1M HCl. The inhibition efficiency increased with increase in the concentration of the inhibitor but decreased with increase in temperature. Inhibition efficiency also was found to increase as immersion time increased. The inhibitive action was due to adsorption of the date palm leaf components on the steel, which was consistent with the Langmuir isotherm.

Date palm leaf extract (DPLE) is an effective inhibitor at room temperature and can be used to protect plain carbon steel from corrosion in HCl solution.

This study provides new information on the inhibiting characteristics of DPLE under specified conditions. The environmentally friendly inhibitor could find possible applications in metal surface anodizing and acid pickling processes.

To reduce the corrosion of oil‐ and gas‐well equipment during acid treatment, the acid must be inhibited. The behaviour of N‐80 oilfield material in 15 per cent hydrochloric acid solution inhibited by different inhibitor formulations containing amine, ester and a quaternary ammonium compound was studied at 303K for five hours by the mass loss method. The corrosion rates were obtained by polarisation. Impedance studies were carried out to evaluate the performance of the inhibitor formulations. It was found that the formulation containing 3,000ppm amine, 1,000ppm ester and 1,000ppm quaternary ammonium compound was effective for the specific oil‐well tubular material.