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The purpose of this paper is to analyze merchandise trade patterns among the GCC states with the backdrop of economic diversification within these economies.

This empirical research quantitatively analyses patterns of merchandise trade among the GCC states during 1995-2015 with specific focus on concentration, diversification and similarity of (export and import) trade indices as well as diversification within GCC economies.

The paper concludes that while Bahrain merchandise export structure shows dissimilarity when compared with other GCC states during 1995 and 2015, its imports appear to be very similar with those of the rest. The other five GCC states show more similarity among themselves in both merchandise exports and imports than that of Bahrain. Only UAE has shown an increase in both concentration and diversification indices though the increased numbers are still lower than those of the other GCC states and low in absolute terms.

The GCC has embarked on economic diversification; however, there is relatively less trade within the GCC as compared with other regional trading blocks. The paper considers trade within the GCC to explore the degree of similarity, diversification and concentration of traded products of each country. Further study should analyze the impact of diversification on intra-GCC trade. The results of this paper will be of value to GCC policymakers for providing a clear rationale for boosting trade and diversification with the long-term goal of a single currency economic union.

This paper aims to propose an enhanced static model of commercial braided pneumatic artificial muscles (PAMs), which is fully analytical without the need for experimentally determined parameters.

To address the highly nonlinear issues of PAMs, the enhanced model is derived considering the irregular shapes close to their end-fittings, as well as the elastic energy stored in both their braids and rubber bladders. The hysteresis characteristics of PAMs are also explored by analyzing the friction in the crossovers of the interlacing braided strands, together with that between the strands and their surrounding bladders. The isobaric and isometric experiments of a commercial PAM are conducted to demonstrate the enhancement, and the model accuracy is evaluated and compared with some existing models in terms of root mean square errors (RMSEs). Additionally, the proposed model is simplified to facilitate the applications that entail high computational efficiency.

The proposed model agrees well with the experimental results, which indicates its viability to accurately predict the static behaviors. An overall RMSE of 5.24 N shows that the enhanced model is capable of providing higher accuracy than the existing analytical models, while keeping the modeling cost at a minimum.

The proposed model, taking account of non-cylindrical shapes, elastic energy and friction, succeeds in enhancing the static predictions of commercial PAMs. The fully analytical model may accelerate the development of novel PAM-based robots for high-precision control, while giving a deeper understanding of commercial PAMs.

The purpose of this study is to bring down collective information about various issues encountered in modelling of rotor systems.

The most important and basic part of “rotor dynamics” is the study related to its different modelling techniques which further involves the analysis of shaft for understanding the system potential, competence and reliability. The issues addressed in this study are classified mainly into two parts: the initial part gives out a vast overview of significant problems as well as different techniques applied to encounter modelling of rotor systems, while the latter part of the study describes the post-processing problem that occurs while performing the dynamic analysis.

The review incorporates the most important research works that have already placed a benchmark right from the beginning as well as the recent works that are still being carried out to further produce better outcomes. The review concludes with the modal analysis of rotor shaft to show the importance of mathematical model through its dynamic behaviour.

A critical literature review on the modelling techniques of rotor shaft systems is provided from earliest to latest along with its real-time application in different research and industrial fields.

Reports on some of the points and predictions made in a lecture at the Institute of Food Research, Norwich Laboratory Open Day.

A successful five-generation family business group in India separates its ownership role from its operational management role to meet the needs of a more global economy. This includes hiring professional nonfamily business unit managers as well as including nonfamily directors on the corporate board.

The purpose of this paper is to theoretically investigate the effects of nanoparticle migration on the heat transfer enhancement at film boiling of nanofluids. The modified Buongiorno model is used for modeling the nanofluids to observe the effects of nanoparticle migration.

The governing partial differential equations including continuity, momentum, energy and nanoparticle continuity are transformed to ordinary ones and solved numerically. For nanoparticle distribution, an analytical expression has been found. The results have been obtained for different parameters, including the Brownian motion to thermophoretic diffusion N_BT, saturation nanoparticle volume fraction ϕ_sat and normal temperature difference.

A closed-form expression for nanoparticle distribution is obtained, and it is indicated that nanoparticle migration significantly affects the flow fields and thermophysical properties of nanofluids. It was shown that temperature gradient at heated wall grows as the migration of nanoparticles increases, which has positive effects on the heat transfer rate. However, decrement of thermal conductivity at heated wall because of nanoparticle depletion plays a negative role in heat transfer enhancement. In fact, there is a tradeoff between thermal conductivity reduction and an increment in temperature gradient at the wall, which determines the net enhancement/deterioration of the heat transfer rate.

Flow has been assumed to be laminar, and the vapor temperature is constant such that boiling is the only heat transfer mechanism between the liquid-vapor interface. Also, the shear stress at the liquid-vapor interface is assumed to be negligible. The film thickness is small relative to the plate length to justify the boundary layer assumptions. Inertia forces are neglected relative to shear stress forces.

Outcomes of the present study are suitable for several heat exchange purposes such as evaporation and condensation in heat pipes, immersion, microchannel cooling of microelectronics and crystal growth.

The novelty of this paper has three aspects: modeling the film boiling of nanofluids considering the effects of nanoparticle migration; how it influences the cooling performance; and an analytical expression for the nanoparticle distribution at film boiling of nanofluids.

Purpose: The chapter aims to discuss the importance of economic development tourism in the United Arab Emirates and the role of entrepreneurship in financial growth, as it is an important aspect in the business environment of tourism. Having said that, the UAE has made remarkable progress in sustaining its economic growth and tourism development over the past decades.

Methodology: To review the importance of the economic development tourism in the United Arab Emirates and the role of entrepreneurship in financial growth, the authors have explored journals from the Scopus, Science direct, Google scholar, and EBSCOHost databases. Furthermore, the Latest reports from UNO and UAE are also examined to find the tourism statistics of past years.

Findings: This study explored the contribution of the tourism industry in enhancing the economic development of the country. This chapter highlighted the past and current trends in tourism in the UAE. Entrepreneurship is considered to be one of the major important outcomes of increased tourism in the country. UAE has also focused on every subject linked to tourism. Furthermore, the country has noted entrepreneurship as a driving factor for tourism. Therefore, various steps have been taken to encourage tourism and entrepreneurship, such as developing infrastructure, along with the implementation of tourism and entrepreneurial education.

Limitations: Like other research studies, this study also has some limitations. The latest reports available were of 2017 to 2019; therefore, current year trends are not explored extensively. Also, due to the scarcity of literature on entrepreneurial tourism in the UAE, this study has reviewed limited articles from UAE.

Social Implications: A more “integrative destination-marketing” process should be promoted with a concerted focus on social identity, cultural sustainability, and religiosity. The overall objective would, therefore, be to develop positive perceptions of destinations such as Dubai that are consistent with its Islamic roots, indigenous peoples, and social and cultural bases.

Originality: To the best of the authors’ knowledge, this chapter is one of its own kind. There are no similar studies have been conducted in the context of the UAE. This study has opened the gates for future research in the tourism sector in UAE.

The purpose of this paper is to design and develop precipitation hardened Al-Mg alloy imparting enhanced strength with acceptable ductility through minor addition of Sc and Cr by using multi-objective genetic algorithm-based searching. In earlier attempts of strengthening aluminum alloys, owing to the formation of Al₃Sc and Al₇Cr phase, addition of Sc and Cr have yielded attractive precipitation hardening, respectively. Both the Al-Sc and Al-Cr system are quench sensitive due to presence of a sloping solvus in their phase diagrams. It is also known that both the Al₃Sc and Al₇Cr phases nucleate directly from the supersaturated solid solution without formation of GP-zones or transient phases prior to the formation of the Al₃Sc and Al₇Cr. Sc also found to have beneficial effect on the corrosion property of such alloys. In view of the above, it is of interest to explore the possibility of enhancing the age hardening effect in Al-Mg alloy by addition of Sc and Cr.

The paper uses an approach where experimental information of two different alloy systems (namely, Al-Mg-Sc and Al-Cr) has been combined to generate a single database involving the potential features of both the systems with the aim to formulate the suitable artificial neural network (ANN) models for strength and ductility. The models are used as the objective functions for the optimization process. The patterns of the optimized Pareto front are analyzed to recognize the optimal property of the alloy system. The hitherto unexplored Al-Mg-Sc-Cr alloy, designed from the Pareto solutions and suitably modified on the basis of prior knowledge of the system, is then synthesized and characterized.

The paper has demonstrated the ANN- and genetic algorithm (GA)-based design of a hitherto unexplored alloy by utilizing the existing information concerning the component alloy systems. The paper also established that analyses of the Pareto solutions generated through multi-objective optimization using GA provide an insight of the variation of the parameters at different combination of strength and ductility. It also revealed that the Al-Mg-Sc-Cr alloy has exhibited a two-stage age hardening effect. The first and second stages are due to the precipitation of Al₃Sc and Al₇Cr phases, respectively.

In the present study the two alloy systems are used in tandem to develop models to describe the properties involving the distinct mechanistic features of phase evolution inherent in both the systems. Though the ANN models having the capability to capture huge non-linearity of a system have been employed to predict the convoluted effects of those characteristics when an alloy containing Mg, Sc and Cr are added simultaneously, but the ANN models predictions can be checked experimentally by the future researchers.

The paper demonstrates the role of scandium and chromium addition on the ageing characteristics of the alloy by analyzing the age hardening behavior of the designed alloy in cast and cold rolled condition clearly.

The approach stated in this paper is a novel one, in the sense that experimental data of two different alloy systems have been clubbed to generate a single database with the aim to formulate the suitable ANN models for strength and ductility.

Despite the importance of knowledge sharing (KS), organizations find it difficult to motivate their employees to share their knowledge with co-workers. Based on a combination of the group value model and the socialization resources theory (SRT), this study is, therefore, an endeavor to contribute to the understanding of how organizations can develop efficacious tacit knowledge sharing (TKS)-strategies by harnessing insights from the impact of respectful engagement (RE) and workplace friendship (i.e. friendship opportunity and friendship prevalence).

Group value model and SRT are used to develop a new pathway to TKS which focuses on how RE among employees contributes to the development of workplace friendship which in turn facilitates TKS. Self-reported data were collected online from 593 employees working in various organizational sectors. Hypotheses were tested with structural equation modeling (SEM).

The results suggest that RE is an essential precursor of TKS, having both direct positive relationship with TKS and partial indirect positive relationship through friendship opportunity and friendship prevalence. RE was also positively related to the two facets of workplace friendship (i.e. friendship opportunity and friendship prevalence). Both friendship opportunity and friendship prevalence were positively related to TKS.

These findings underscore the importance of implementing initiatives that support positive interrelations characterized by respect at work in order to promote TKS.

By linking RE to TKS, this study adds new insight to the relational basis of sharing personal asset/resource as tacit knowledge. The inclusion of mediation path helps in shedding light and opening up a black box of RE-TKS interface.