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Indoor environmental quality (IEQ) in buildings has an impact on people’s health, productivity and comfort. Maintaining the highest possible IEQ level in complex buildings, such as health care, is difficult due to economic and organizational constraints. This study aims to categorize the vicinities in a typical health-care facility in terms of importance and criticality in relation to the various IEQ factors, as well as to develop an IEQ assessment procedure.

A comprehensive literature review, established standards and structured interviews with industrial hygiene professionals in health-care settings were used in this study. To test the applicability of the developed IEQ assessment procedure, a pilot study was conducted in an existing health-care facility.

This study categorized health-care facilities into various vicinities and discovered three respondents group had varying IEQ perceptions (facility managers, environmental health specialists and nurses). According to the findings, indoor air quality is the most important and dominant factor influencing overall IEQ in health-care facilities. The trial application of the framework shows that much work is needed to improve the level of response and readiness of facility management and occupants to allow for the effective use of the developed procedure.

Previous research did not include a detailed categorization of vicinities in health-care buildings based on IEQ requirements. The findings of this study will help to close this knowledge gap and guide facility managers and operators in recognizing the relative importance of different IEQ factors, maintaining functional requirements and identifying priorities when developing maintenance and operational procedures and allocating resources.

This paper aims to numerically investigate the impact of gas diffusion layer (GDL) anisotropic transport properties on the overall and local performance of polymer electrolyte fuel cells (PEFCs).

A three-dimensional numerical model of a polymer electrolyte fuel cell with a single straight channel has been developed to investigate the sensitivity of the fuel cell performance to the GDL anisotropic transport properties – gas permeability, diffusivity, thermal conductivity and electrical conductivity. Realistic experimentally estimated GDL transport properties were incorporated into the developed PEFC model, and a parametric study was performed to show the effect of these properties on fuel cell performance and the distribution of the key variables of current density and oxygen concentration within the cathode GDL.

The results showed that the anisotropy of the GDL must be captured to avoid overestimation/underestimation of the performance of the modelled fuel cell. The results also showed that the fuel cell performance and the distributions of current density and oxygen mass fraction within the cathode GDL are highly sensitive to the through-plane electrical conductivity of the GDL and, to a lesser extent, the through-plane diffusivity, and the thermal conductivity of the GDL. The fuel cell performance is almost insensitive to the gas permeability of the GDL.

This study improves the understanding of the importance of the GDL anisotropy in the modelling of fuel cells and provides useful insights on improving the efficiency of the fuel cells.

Realistic experimentally estimated GDL transport properties have been incorporated into the PEFC model for the first time, allowing for more accurate prediction of the PEFC performance.

The purpose of this paper is to investigate the effects of hydrogen humidity on the performance of air-breathing proton exchange membrane (PEM) fuel cells.

An efficient mathematical model for air-breathing PEM fuel cells has been built in MATLAB. The sensitivity of the fuel cell performance to the heat transfer coefficient is investigated first. The effect of hydrogen humidity is also studied. In addition, under different hydrogen humidities, the most appropriate thickness of the gas diffusion layer (GDL) is investigated.

The heat transfer coefficient dictates the performance limiting mode of the air-breathing PEM fuel cell, the modelled air-breathing fuel cell is limited by the dry-out of the membrane at high current densities. The performance of the fuel cell is mainly influenced by the hydrogen humidity. Besides, an optimal cathode GDL and relatively thinner anode GDL are favoured to achieve a good performance of the fuel cell.

The current study improves the understanding of the effect of the hydrogen humidity in air-breathing fuel cells and this new model can be used to investigate different component properties in real designs.

The hydrogen relative humidity and the GDL thickness can be controlled to improve the performance of air-breathing fuel cells.

This paper aims to measure customer-based brand equity in the context of hotels, and to develop and empirically validate a new scale, named guest-based hotel equity (GBHE), by incorporating the customer perceived value of hotels as a multidimensional construct in addition to its traditional dimensions (i.e. brand awareness and brand image).

A structured and self-administered survey was used, targeting 348 hotel guests who were surveyed about their experience with the last hotel they had stayed in during the previous year. Exploratory and confirmatory factor analyses were used to assess the research constructs dimensions, unidimensionality, convergent and discriminant validity and composite reliability.

The empirical findings indicate that GBHE is a multidimensional construct with nine dimensions, namely, hotel awareness, hotel overall image and seven dimensions of customer perceived value (i.e. the values of price, quality, self-gratification, aesthetics, prestige, transaction and hedonism). The new scale is found to have excellent psychometric properties; it has demonstrated its predictive power on behavioral intentions.

Although the authors believe that the sample size was reasonable and adequate for conducting CFA analysis, a bigger sample would be better and might increase the robustness of the proposed scale. In addition, to avoid the retrieval failure problem, hotel guests should be surveyed just after their stay in the hotel or not long afterwards. Further, the hotel classification or hotel star rating was not considered in developing and validating the GBHE scale.

The findings of this study provide hotel managers with a new tool to use in assessing the experiential value of the hotel brand equity, other than conventional hotel awareness and brand image. Further, using the multidimensional construct of perceived value provides hotel managers with more insights into what aspects of hotel brand equity they should focus on to influence the behavioral intentions of their guests.

The originality of this research is highlighted in several points. First, it develops and empirically validates a new scale to measure customer-based brand equity in the hotel context, that is, GBHE. Second, it incorporates the customer perceived value of hotels not as a unidimensional construct that is concerned only with cost, but as a multi-dimensional construct which includes in the GBHE scale dimensions that are both cognitive (i.e. of price and quality) and affective (i.e. of self-gratification, aesthetics, prestige, transaction and hedonism) in addition to its traditional dimensions (i.e. brand awareness and brand image). Third, it assesses the predictive power and relative importance of the GBHE dimensions for behavioral intentions (i.e. loyalty to hotels). Finally, no research has been done so far on the brand equity of hotels in the United Arab Emirates (UAE), although it is considered a fertile soil for tourism in the Arabian region.

This study aims to examine the roles of advertising (ADV) and sales promotion (SP) in creating airline brand equity (BE) in the UAE, and to test the mediational effect of customer perceived value on the proposed relationships. Additionally, the study examines the outcomes of airline BE (i.e. trust, satisfaction and loyalty).

A structured and self-administered survey was used targeting 234 passengers, from which 197 were valid for the analysis. Exploratory and confirmatory factor analyses were used to assess the research constructs unidimensionality, validity and composite reliability.

The empirical findings support the direct relationship between ADV and BE. Perceived value fully mediates the effect of SP on BE. In addition, BE positively affects trust, satisfaction and loyalty.

Future research could investigate BE and perceived value as multidimensional constructs. Additionally, future research should expand the effect of other variables such as airline type, airline class and other marketing mix elements.

The findings from this research highlight the importance of both ADV and sale promotion in enhancing airline BE, and the pivotal role of perceived value.

The originality of this research is highlighted in conceptualizing a parsimonious model of the preceding constructs (i.e. ADV, SP, customer perceived quality) and subsequent constructs of BE (i.e. customer trust, customer satisfaction, customer loyalty), which has never been investigated collectively in one model in the literature particularly in the airline’ context of emerging economies such as UAE.

This paper aims to investigate the impact of three different flow channel cross sections on the performance of the fuel cell.

A comprehensive three-dimensional polymer electrolyte membrane fuel cell model has been developed, and a set of conservation equations has been solved. The flow is assumed to be steady, fully developed, laminar and isothermal. The investigated cross sections are the commonly used square cross section, the increasingly used trapezoidal cross section and a novel hybrid configuration where the cross section is square at the inlet and trapezoidal at the outlet.

The results show that a slight gain is obtained when using the hybrid configuration and this is because of increased velocity, which improves the supply of the reactant gases to the catalyst layers (CLs) and removes heat and excess water more effectively compared to other configurations. Further, the reduction of the outlet height of the hybrid configuration leads to even better fuel cell performance and this is again because of increased velocity in the flow channel.

The data generated in this study will be highly valuable to engineers interested in studying the effect of fluid cross -sectional shape on fuel cell performance.

This study proposes a novel flow field with a variable cross section. This design can supply a higher amount of reactant gases to the CLs, dissipates heat and remove excess water more effectively.

This paper aims to numerically solve fully developed laminar flow in trapezoidal ducts with rounded corners which result following forming processes.

A two-dimensional model for a trapezoidal duct with rounded corners is developed and conservation of momentum equation is solved. The flow is assumed to be steady, fully developed, laminar, isothermal and incompressible. The key flow characteristics including the Poiseuille number and the incremental pressure drop have been computed and tabulated for a wide range of: sidewall angle (θ); the ratio of the height of the duct to its smaller base (α); and the ratio of the fillet radius of the duct to its smaller base (β).

The results show that Poiseuille number decreases, and all the other dimensionless numbers increase with increasing the radii of the fillets of the duct; these effects were found to amplify with decreasing duct heights or increasing sidewall angles. The maximum axial velocity was shown to increase with increasing the radii of the fillets of the duct. For normally used ducts in hydrogen fuel cells, the impact of rounded corners cannot be overlooked for very low channel heights or very high sidewall angles.

The data generated in this study are highly valuable for engineers interested in estimating pressure drops in rounded trapezoidal ducts; these ducts have been increasingly used in hydrogen fuel cells where flow channels are stamped on thin metallic sheets.

Fully developed laminar flow in trapezoidal ducts with four rounded corners has been solved for the first time, allowing for more accurate estimation of pressure drop.

The purpose of this paper is to identify customers’ perceived value constructs of shopping malls from the perspective of Muslim shoppers and to develop items for measuring these constructs, empirically validate the scale, and carry out an initial investigation of the effect of these dimensions on behavioural outcomes.

By means of a multi-dimensional procedure on a sample of 329 Muslim mall shoppers in the UAE, the authors have developed a scale of measurement of these shoppers’ perceived value of malls through grouping 30 value items into eight dimensions.

The study constructed and validated a scale of perceived value of malls taking into consideration the mall shopper’s religion (i.e. Islam). The authors name this new scale Muslim MALLVAL. This scale demonstrates that, like any other shoppers, Muslims who shop in malls assess the shopping experience through both cognitive and affective values in addition to the Islamic value of the mall. The study in addition reveals that the dimensions of Muslim MALLVAL have significant positive influences on behavioural outcomes such as willingness to continue shopping and recommendation of the mall to others.

This study is carried out on Muslim shoppers in the UAE context. However, the authors urge other researchers to replicate the study and get replies from different countries and in particular to use the measures developed in this study to test their robustness.

Muslim mall shoppers evaluate not only the traditional aspects of mall value but also the religious identity related aspects that contribute to the value creation. Therefore, mall developers and managers who target Muslim shoppers (residents and/or tourists) should create and maintain the appropriate shopping environment for Muslim shoppers.

This study is the first to provide an integrative scale for the perceived value of shopping malls from the perspective of Muslim shoppers.

The purpose of this paper is to numerically investigate the effects of the shape on the performance of the cathode catalyst agglomerate used in polymer electrolyte fuel cells (PEFCs). The shapes investigated are slabs, cylinders and spheres.

Three 1D models are developed to represent the slab like, cylindrical and spherical agglomerates, respectively. The models are solved for the concentration of the dissolved oxygen using a finite element software, COMSOL Multiphysics®. “1D” and “1D axisymmetric” schemes are used to model the slab like and cylindrical agglomerates, respectively. There is no one-dimensional scheme available in COMSOL Multiphysics® for spherical coordinate systems. To resolve this, the governing equation in “1D” scheme is mathematically modified to match that of the spherical coordinate system.

For a given length of the diffusion path, the variation in the performances of the investigated agglomerates is dependent on the operational overpotential. Under low magnitudes of the overpotentials, where the performance is mainly limited by reaction, the slab-like agglomerate outperforms the spherical and cylindrical agglomerates. In contrast, under high magnitudes of the overpotentials where the agglomerate performance is mainly limited by diffusion, the spherical and cylindrical agglomerates outperform the slab-like agglomerate.

The current advances in the nano-fabrication technology gives more flexibility in designing the catalyst layers in PEFCs to the desired structures. If the design of the agglomerate catalyst is to be assessed, the current micro-scale modelling offers an efficient and rapid way forward.

The current micro-scale modelling is an efficient alternative to developing a full (or half) fuel cell model to evaluate the effects of the agglomerate structure.

The paper aims to determine the attractiveness factors of UAE shopping malls from the shoppers' perspective and then to segment shoppers according to these attractiveness factors.

A survey of university staff and principal component factor analysis were used to identify shopping mall attractiveness factors. Segmentation approach using K‐means cluster analysis was also used to segment mall shoppers due to the identified factors.

This study revealed six mall attractiveness factors from the shoppers' perspective: comfort, entertainment, diversity, mall essence, convenience, and luxury. It also arrived at three mall shopper segments, specifically, relaxed shoppers, demanding shoppers, and pragmatic shoppers. Each segment was profiled in terms of mall attractiveness attributes, demographics and shopping behaviour.

This study is limited in that it surveyed UAE University staff as shoppers. Thus, findings may not be representative of UAE shoppers in general.

Identifying mall attractiveness factors for a segmented market gives a better understanding about patronage motives than when it is applied to the market as a whole. This enables mall managers to develop the appropriate retailing strategies to satisfy each segment.

This is the first study to provide an insight of mall attractiveness factors as identified by different shopper segments in an Arabian environment without ignoring the special cultural differences in the UAE.