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This paper aims to analyze the accuracy of the single and two-phase numerical methods for calculation of ferrofluid convective heat transfer in the presence of a magnetic field. The findings of current study are compared with previous single-phase numerical results and experimental data. Accordingly, the effect of various parameters including nanoparticles concentration, Reynolds number and magnetic field strength on the performance of the single and two-phase models are evaluated.

A two-phase mixture numerical study is carried out to investigate the influence of four U-shaped electromagnets on the hydrodynamic and thermal characteristics of Fe₃O₄/Water ferrofluid flowing inside a heated channel.

It is observed that the applied external magnetic field signifies the convective heat transfer from the channel surface, despite local reduction at a few locations. The maximum heat transfer enhancement is predicted as 23% and 25% using single and two-phase models, respectively. The difference between the results of the two models is mainly attributed to the slip velocity effect which is accounted for in the two-phase model. The magnetic field gradient leads to a significant increase in the slip velocity which in turn causes a slight difference in velocity and temperature profiles obtained by the single and two-phase models in the magnetic field region. According to percentage error calculation, the two-phase method is generally more accurate than the single-phase method. However, the percentage error of both models improves by decreasing either magnetic field intensity or Reynolds number.

For the first time in the literature, to the best of the authors’ knowledge, the current work analyzes the accuracy of the single and two phase numerical methods for calculation of ferrofluid convective heat transfer in the presence of a magnetic field.

The purpose of this paper is to outline more computational schemes which provide a low computational cost approach to analyze flow characteristics through tube bundles. Flow through tube bundles has been numerically simulated by means of an alternative approach so as to assess flow behavior and its characteristics.

A Cartesian‐staggered grid based finite‐volume solver has been implemented. Furthermore, the ghost‐cell method in conjunction with Great‐Source‐Term technique has been employed in order to directly enforce no‐slip condition on the tubes boundaries. Before giving a solution for flow field through tube bundles, the accuracy of the solver is validated by simulation of flow in the cavity and also over a single circular cylinder. The results are completely compatible with the experiments reported in the literature.

Eventually, the flow through two types of tube bundles in in‐line square and general staggered arrangements in Re = 100 are simulated and analyzed. For these tube bundles that are being studied, the maximum drag and lift coefficients and maximum gap velocities have been numerically obtained. The same simulations have been also performed for the cases where the tube bundles are confined by two lateral walls.

These configurations are frequently used in heat exchangers, steam boilers, nuclear reactors, and many mechanical structures.

The adapted method is firstly implemented to simulate flow through tube bundles and the analyzed simulations have not previously been presented by other researches.

This study addresses the reliability of a composite fiber (carbon fibers/epoxy matrix) at microscopic level, with a specific focus on its behavior under compressive stresses. The primary goal is to investigate the factors that influence the reliability of the composite, specifically considering the effects of initial fiber deformation and fiber volume fraction.

The analysis involves a multi-step approach. Initially, micromechanics theory is employed to derive limit state equations that define the stress levels at which the fiber remains within an acceptable range of deformation. To assess the composite's structural reliability, a dedicated code is developed using the Monte Carlo method, incorporating random variables.

Results highlight the significance of initial fiber deformation and volume fraction on the composite's reliability. They indicate that the level of initial deformation of the fibers plays a crucial role in determining the composite reliability. A fiber with 0.5% initial deformation exhibits the ability to endure up to 28% additional stress compared to a fiber with 1% initial deformation. Conversely, a higher fiber volume fraction contributes positively to the composite's reliability. A composite with 60% fiber content and 0.5% initial deformation can support up to 40% additional stress compared to a composite containing 40% fibers with the same deformation.

The study's originality lies in its comprehensive exploration of the factors affecting the reliability of carbon fiber-epoxy matrix composites under compressive stresses. The integration of micromechanics theory and the Monte Carlo method for structural reliability analysis contributes to a thorough understanding of the composite's behavior. The findings shed light on the critical roles played by initial fiber deformation and fiber volume fraction in determining the overall reliability of the composite. Additionally, the study underscores the importance of careful fiber placement during the manufacturing process and emphasizes the role of volume fraction in ensuring the final product's reliability.

The purpose of this paper is to provide a thorough empirical investigation of the potential link between corporate innovations and corporate competitiveness in the context of the UK IT industry.

This research uses a panel of 216 UK IT firms for the period from 2000 to 2016. The sample data for this study were extracted from the Worldscope, extracted from the Datastream database from Thomson Reuters. For the analysis of the data, the generalised method of moments model is applied.

The results of this study provide empirical evidence that there exists a strong, positive link between corporate innovations and corporate competitiveness. Such evidence further reinforces the common view in the current literature of strategic management that because of the nature of their business, firms in the IT industry need to enhance their innovative capacities on a continual basis because of their critical role on these firms’ success and survival. Also, it is found that when the proxies for corporate innovations are lagged by two periods, their impact on corporate competitiveness becomes relatively more significant. However, when they are further lagged, i.e. by three periods, such an impact turns out to be relatively less pronounced.

The data gathered for this paper was restricted to IT-oriented firms in the UK. Using a secondary database (Datastream), the paper considered the period of 2000-2016.

The research makes a significant contribution to the current debate on the relationship between information technology, innovation and performance, referred to in the literature as the productivity paradox, by studying the problem in the IT industry. It supports organisations from the sector in their efforts to deal with the dynamic nature of technological innovations and of the context where they operate. Methodologically, the way the study has measured the concepts of innovation and performance and the lessons learned from their analysis has also brought value to the research.

Although a vast amount of research has been started to gauge customer satisfaction using surveys, the influence of COVID-19 on passengers' satisfaction has not received enough attention. Hence, the primary purpose of this research is to determine the dominant themes that emerged from airline travelers' online reviews and to determine attributes that are pertinent to the satisfaction of passengers flying with low-cost carriers (LCC) during the COVID-19 outbreak. In addition, this study investigates whether the salient themes of passengers' overall experiences vary by traveler origin, which may give more insight into airline sector market segmentation.

Leximancer software was used to construct concepts from words, followed by themes in the data analysis.

The analyses revealed eight themes in descriptions of “travel experiences” for airline passengers. These are “flights,” “staff,” “service,” “hygiene,” “cancellations,” “legroom,” “COVID-19” and “test”. Negative reviews associated with “cancellations,” “refund,” “waiting” and “baggage” (handling) concepts.

The findings provide important information about airline passengers' overall experiences. Limited studies have comprehensively considered various satisfaction categories of airline travelers using online reviews.

The main aim of this paper is to study the effects of organizational culture on environmental responsiveness capability (ERC), both directly and through the mediation of knowledge management (KM) in selected Iranian Industrial Research Organizations (IIRO). Furthermore, the effects of four types of organizational culture on ERC and KM in the target population are compared.

Relationships between the ERC, KM and organizational culture are considered using survey data through the structural equation modelling approach. Five-point Likert questionnaire has been used as a tool for measuring variables. The authors sample includes 276 members of 13 selected target organizations whose names are not mentioned due to prior agreement.

Results show that organizational culture has a positive and significant relationship with ERC, both directly and indirectly through the mediation of KM. Additionally, compared with other types of organizational cultures, innovativeness culture has the highest correlation with ERC, both directly and through KM as a mediating variable. Furthermore, cooperativeness culture has a direct significant relationship with ERC, whereas consistency and effectiveness cultures indirectly have significant and positive relationships with ERC through KM. Therefore, results of this research provide appropriate evidence that ERC can be affected directly by innovativeness culture and KM.

The advantage of this paper compared to other related research is to study on ERC based on cultural and knowledge-related variables. Hence, it can extend the literature of ERC, and it can be useful for the managers who are dealing with industrial research company.

Jujube fruit (JF) (Ziziphus jujuba Mill.) is used as pharmaceuticals food, flavors and food additives. The purpose of this paper is to study the suitability of JF incorporation into a commercial sponge cake formulation, and to produce a nutritious bakery product with appropriate organoleptic and technological characteristics.

The optimal level of JF was incorporated into sponge cake using a custom mixture design with three independent variables, namely, refined wheat flour (RWF, 15–28 percent), sugar (7–22 percent) and JF (0–28 percent), as well as several responses, including physical properties, texture profile analysis (TPA), sensorial evaluation and color features. Moreover, physicochemical properties (TPA and oxidative indices) of optimal cake (two of the best JF levels) were compared with control sample (without JF) during 51 days storage period, while two baking temperatures (180°C and 170°C) were used.

The optimal amounts of RWF (21.19 percent), sugar (21.20 percent) and JF (7.61 percent) required for making the sample with maximum springiness, cohesiveness, specific volume, sensorial scores and yellowness, as well as the lowest firmness, baking loss and browning were determined. Desirable effects of JF on the cake quality well maintained throughout the storage period, as TPA attributes, peroxide value, ultraviolet absorbance and acid value showed less changes in JF-incorporated cake than the control sample.

Incorporating JF (~7 percent) into the batter was successful to improve the physicochemical properties in both fresh and stored cake with chocolate-like color.

This study provides a critical review of the literature on information literacy in the workplace and its relevant issues. The purpose of this study is to examine two elements: how the predominantly academic information literacy is experienced in the workplace; and review how academically based information literacy frameworks can be used to increase performance in the workplace.

A critical approach to information literacy was implemented for the introduction and background information by searching for scholarly publications referring to information literacy and information literacy in the workplace. Overall, 65 published articles in English were selected and found suitable.

According to the existing literature, very few frameworks tailored to specific workplaces have been discovered and were all found to be pertinent to academic settings that included researchers. The review revealed the perceived positive role of information literacy in raising work performance. The paper concludes that the benefit for information literate employees and employers is apparent, but those differences in academic information literacy and workplace information literacy are significant.

Information literacy frameworks for the workplace, when used, are still heavily reliant on the educational sector and need to be further researched in order for them to adequately address specific workplace contexts and their socially collaborative information literacy activities.

This paper aims to investigate the effect of coating microstructure, mechanical and oxidation property on the tribological behaviour of low-pressure plasma spraying (LPPS) tungsten carbide/cobalt (WC-Co) coatings.

WC-12Co and WC-17Co coatings were deposited via the LPPS spraying method. Tribological tests on the coatings were performed using a high-temperature ball-on-disc tribometer at temperatures from room temperature (RT, approximately 25 °C) up to 800 °C in ambient air.

WC-12Co coating contained brittle phases, pores and microcracks, which led to the low hardness, and finally promoted the splat delamination and the carbide debonding during wear. WC-17Co coating had higher cobalt content which benefited the coating to contain more WC particles, less brittle phases, pores and nearly no microcracks, and resulted in the high hardness and better wear resistance. Higher cobalt content also decelerated the oxidation rate of the coating and promoted the formation of cobalt oxides and CoWO4, which were able to maintain the load-bearing capacity and improve the tribological behaviour of the coating below 650°C. Above 650°C, the increase of oxidation degree and the decrease of mechanical property deteriorated the wear resistance of coatings.

The LPPS WC-Co coating with higher cobalt content had better tribological properties at different temperatures. The LPPS WC-Co coatings should not be used as wear-resistant coatings above 650 °C.

This chapter evaluates the effects of second-home phenomena in several cities which, due to their unique spatial characteristics, are the target destination for the people who wish to escape routine life. The study setting, the Caspian Sea coastal zone, is endowed with natural comparative advantages due to its lush and green landscape, as well as sun, sea, and sand tourism, and has been experiencing high growth of second homes and village tourism during recent decades. Social exchange and stakeholder theories within the context of sustainable development compose the frame on which this study is based. The findings are discussed and followed with implications and hints for future research.