Search results

A fully three‐dimensional model has been applied to an oil‐fired water tube boiler in order to predict the flow, temperature, mixture fraction, species concentrations and the heat flux distributions to the furnace walls. The partial differential equations governing conservation of mass, momentum and energy as well as those describing the combustion phenomena are discretized by a finite volume method and solved numerically. Radiative heat transfer is handled by the discrete transfer method. Predicted results are presented and compared with experimental data for the heat fluxes. The results have suggested that 3‐D models of the present kind can be used with some confidence for design calculations.

The high costs of collection and transportation of municipal solid waste (MSW) on the overall waste management budget (sometimes more than 75 per cent) makes it an issue to be urgently addressed for improvement. The paper aims to focus on the optimisation of routing networks for waste collection/transportation.

The paper proposes herein the application of geographic information system (GIS) 3D route modelling for waste collection/transportation to optimise the route according to the minimum fuel consumption criterion to different municipalities of the island of Santo Antao of Cape Verde.

The optimisation for the lowest fuel consumption yields 52 per cent savings in fuel, when compared to that for the shortest distance, even travelling a 34 percent longer distance, which shows the importance of considering simultaneously the relief of the territory and the lowest fuel consumption criterion when optimising vehicle routes.

With such a supporting decision tool savings in fuel are huge, the efficiency of management systems is improved and the environmental impact during daily operation is reduced. The GIS 3D route modelling takes into account the effects of both the road inclination and the vehicle load.

The originality of the work lies in the chosen approach. To optimise vehicle routes the criterion of minimum fuel consumption rather than the commonly used shortest distance is used, since fuel consumption is the factor reflecting actual costs relative to MSW management.

This study aims to explore the firm’s and country-level institutional forces that determine banks’ CSR reporting diversity, during the recent global financial crisis.

Specifically, this study assesses whether economic and institutional conditions explain CSR disclosure strategies used by 30 listed and unlisted banks from six countries in the context of the recent 2007/2008 global financial crisis. The annual reports and social responsibility reports of the largest banks in Canada, the UK, France, Italy, Spain and Portugal were content analyzed.

The findings suggest that economic factors do not influence CSR disclosure. Institutional factors associated with the legal environment, industry self-regulation and the organization’s commitments in maintaining a dialogue with relevant stakeholders are crucial elements in explaining CSR reporting. Consistent with the Dillard et al.’s (2004) model, CSR disclosure by banks not only stems from institutional legitimacy processes, but also from strategic ones.

The findings highlight the importance of CSR regulation to properly monitor manager’s’ opportunistic use of CSR information and regulate the assurance activities (regarding standards, their profession or even the scope of assurance) to guarantee the proper credibility reliability of CSR information.

The study makes two major contributions. First, it extends and modifies the model used by Chih et al. (2010). Second, drawn on the new institutional sociology, this study develops a theoretical framework that combines the multilevel model of the dynamic process of institutionalization, transposition and deinstitutionalization of organizational practices developed by Dillard et al. (2004) with Campbell’s (2007) theoretical framework of socially responsible behavior. This theoretical framework incorporates a more inclusive social context, aligned with a more comprehensive sociology-based institutional theory (Dillard et al., 2004; Campbell, 2007), which has never been used in the CSR reporting literature hitherto.

The purpose is to analyse the nutritional adequacy and carbon footprint of intermediated meals provided to preschool children and primary-level students in a Portuguese municipality.

An observational cross-sectional study was conducted with a convenience sampling consisting of school snacks from a Portuguese municipality. The nutritional assessment used food labels and a Portuguese food composition table. The literature review for carbon footprint assessment was conducted by searching for the products under analysis or similar ones.

The results showed that 80% of snacks have a higher energy value than recommended. The majority of options are below recommendations for protein and fat and above recommendations for carbohydrates. The intermediated meals with more dairy products in composition have the highest carbon footprint. The carbon footprint included the packaging of the products, and it wasn't possible to determine the influence of non-food products.

This study has limitations in the fact that we do not know the carbon footprint of Portuguese products and we had to compare them with others, from different countries, with possibly different types of production.

Intermediate meals are inadequate, and the carbon footprint is higher when the intermediated meals include products of animal origin – the reason why the composition of intermediated meals should be redesigned considering the achievement of these targets.

The promotion of intermediated meals that promote the Mediterranean eating pattern contributes to health and well-being and is a vehicle for nutrition education and healthy food consumption in schools.

Many studies have been conducted to analyse the carbon footprint and environmental impact of school meals, but commonly lunch is the meal evaluated and the assessment of intermediated meals' impact is an open field.

This study aims to illustrate the potential of the many centuries-old universities buildings, in European cities, in a historical, architectural, aesthetic and symbolic dimension to diversify and differentiate urban tourist destinations supply.

This is a qualitative study supported by the analysis of public and classified documents, for which the main source is based on webography, and by conducting interviews.

The deficit of cultural tours, in the dimension of built heritage, is identified as one of the weaknesses of the city of Porto, as tourist destination, to be overcome. The interviewees are unanimous in recognizing the cultural, architectural and aesthetic impact of the historic buildings of the University of Porto, and most of them strongly agree with the integration of this legacy into the tourist offer of the city. The strategic sense of the heritage is emphasized, because of its location in charismatic areas of the city. The practice of effective networking, however, falls short of what is required to achieve ambitious and consistent objectives.

The practice of effective networking, however, falls short of what is required to achieve ambitious and consistent objectives.

Emphasis is placed on the cities’ built heritage as a type of heritage that defines their uniqueness. The dissemination of cultural itineraries, which allows tourists and the community itself a broader and deeper cultural knowledge, contributes to the effective understanding of historic cities’ tourism. Given the scarcity of studies on the relationship between historic university buildings and tourism, the relevance of research focuses on highlighting the contribution of these cultural elements, through a network-based dynamic, to urban tourism destinations’ attractiveness. In particular, the University of Porto's potential for the integration of structured tourism products that contribute to the diversification and differentiation of the city of Porto as a destination is illustrated.

The purpose of this paper is to validate and apply enrichment diagrams (EDs) to determine metal and as enrichment and contamination in the sediments of Sepetiba Bay.

Through inducted coupled plasma – optical emission spectrophotometry, total element (As, Cd, Cu, Ni, Pb and Zn) concentrations were assessed for the construction of EDs and comparison with enrichment factors (EFs) in 65 samples collected in Sepetiba Bay.

Based on the EDs, it was observed that the sediments around the urban area of Sepetiba and ItaguaíHarbor were contaminated with Cd, Cu, Ni, Pb and Zn. These contaminants were expected due to the urban and industrial discharges into the bay and the activities at ItaguaíHarbor.

The ED was successful regarding its ability to evaluate inorganic contamination in Sepetiba Bay. In addition, this method was able to define a proper background sample for calculating EFs.

It is essential to develop more environment-friendly energy systems to prevent climate change and minimize environmental impact. Within this scope, many studies are performed on performance and environmental assessments of many types of energy systems. This paper, different from previous studies, aims to prove exergy performance of a low-emission combustor of an aero-engine.

It is a well-known fact that, with respect to previous exergy analysis, highest exergy destruction occurs in the combustor component of the engine. For this reason, it is required to evaluate a low-emission aero-engine combustor thermodynamically to understand the state of the art according to the authors’ best of knowledge. In this framework, combustor has been operated at numerous conditions (variable engine load) and evaluated.

As a conclusion of the study, the impact of emission reduction on performance improvement of the aero-engine combustors exergetically is presented. It is stated that exergy efficiency of the low-emission aero-engine combustor is found to be 64.69, 61.95 and 71.97 per cent under various operating conditions.

Results obtained in this paper may be beneficial for researchers who are interested in combustion and propulsion technology and thermal sciences.

Different from former studies, the impact of operating conditions on performance of a combustor is examined from the viewpoint of thermodynamics.

This study aims to examine the various climate change practices adopted by firms and develop a set of corporate indexes that measure the level of climate change corporate commitment, climate change risk management integration and climate change strategies adoption. Moreover, this study examines the relationship between the aforementioned indexes. The authors claim that there is a positive relationship between the adoption of climate change strategies, corporate commitment and risk management integration. The aforementioned indexes have been used to assess the largest companies in the oil and gas sectors.

To assess this study’s sample companies, a content analysis of their carbon disclosure project (CDP) reports for the years 2012-2015 was conducted. Finally, weights were assigned to the content analysis data based on the results of a survey regarding the difficulty of implementing each climate change practice included in the respective index. The survey sample included climate change experts who are either currently employed in companies that are included in the Financial Times Global 500 (FT 500) list, or work as external partners with these companies.

The present study results highlight the need for developing elaborate corporate indexes, as the various climate change practices have different degrees of difficulty regarding their implementation. Additionally, a general trend in adopting climate change strategies is observed, especially in the field of carbon reduction strategies, which mainly involve the implementation of low carbon technologies. Finally, a positive and significant relationship was found between carbon reduction targets, risk management integration and climate change strategies.

Although international research has extensively examined the importance of managers’ perceptions on environmental issues as an enabling factor in developing environmental strategies, according to the results of our survey, corporations must go beyond top management commitment towards climate change to be able to successfully implement climate change strategies. Incorporation of climate change risk management procedures into a company’s core business activities as well as the establishment of precise carbon reduction targets can provide the basis on which successful climate change strategies are implemented.

Most studies address the issue of climate change management in terms of environmental or sustainability management. Furthermore, research on climate change and its relationship with business management is mainly theoretical, and climate change corporate performance is measured with aggregate indexes. This study focuses on climate change which is examined from a five-dimensional perspective: top management commitment, carbon reduction targets, risk management integration, carbon reduction and carbon compensation strategies. This allows us to conduct an in-depth analysis of the various climate change practices of firms.