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This study aims to question the fact that density has been considered only as an instrument of calculation to be used on regulation mechanisms, without taking into consideration other variables related to density. The paper proposes a framework consisting of four determining factors for urban analysis that have to be considered before starting a densification process: connectivity and permeability of network, mixture of uses, relation to urban morphology and public spaces for each district. The methodological analysis was carried out for the case of the district of Gruta de Lourdes, Quinta Normal, located in northwest Santiago, which has started a densification process the recent years.

The present discussion aims to obtain objective parameters to determine if urban development allows livability and a balanced relationship with actual urban form and diversity. There appear to be four determining factors of urban analysis: connectivity and network permeability, the mixture of uses, public spaces and urban form development. The district of Gruta de Lourdes will be used to delve into these parameters to place the debate around density in objective terms. To look in depth at each of the criteria for evaluating densification processes, various methods were selected for quantifying the observed variables: to evaluate connectivity and integration of a neighborhood with the rest of the city, the spatial configuration analysis “Space Syntax” will be used; to evaluate mix of uses, mixed-use index, or ratio of non-residential use will be used; urban morphology, plot size, housing density (dw/ha), lot coverage and floor area ratio will be used; public spaces, the percentage dedicated to each of these in m²/inhab.

The results allow us to conclude that it is necessary to plan densification processes via an analysis that promotes connectivity, mixture of uses, urban morphology and the available public spaces to understand density as a multivariable phenomenon. In addition, we conclude that the case study district, Gruta de Lourdes, can withstand greater demand for housing as long as the context is taken into account. A possible option to asset the densification potential could be the “infill” strategy, which aims to be a type of intervention that does not change the structure of the neighborhood as new buildings are positioned among existing ones, maintaining the form of the streets and the structure of plot divisions.

The value of the paper is to contribute to the discussion on how to renovate central areas in Latin American cities looking at variables such as connectivity, mixture of uses, urban morphology and public spaces, which are directly related to density. Moreover, the paper contributes to discuss new ways to analyze and measure densification, toward planning a district’s renovation. In addition, the quantitative methodological approach to the densification processes gives a new understanding of how to determine density. Finally, the paper reveals an opportunity to rethink the inner city toward new approaches to renovation developments.

There is a growing importance for public facilitation of corporate social responsibility and involvement of civil organizations in securing territorial cohesion and development. In the present article, the authors focus on how we are to understand a locally sensitive organization of territorial cohesion in the Danish context. Traditional sociological concepts and standardized area-types used for administrative purposes have turned out not being very helpful in understanding the interrelation between inequality, urbanization and territorial cohesion. The authors argue for a processual and relational approach to urbanization.

The present article is based on interview material and policy documents from three Danish case studies representing urban, suburban and rural forms of settlement. The case studies are part of a cross-European research project.

The authors show how territorial governance play a key role in the strategies of densification/de-densification facilitating shielding capacities of collective efficacy, and reversely that bottom-up innovations are crucial for the ability of territorial governance to mobilize territorial capital and mediate in effects of territorial inequality. Spatial imaginaries legitimize these efforts to organize cohesion. The spatial imaginaries work as common frame of references for the interplay between strategies of (de)densification and collective efficacy, and they activate particular balances between growth agendas and everyday life.

These findings represent an original perspective on how and why urbanization impact on places in a more specific and variated way than often portrayed as it highlight how social capacities tied to place might work with or against existing social, economic and cultural structures shaping territorial cohesion.

Corporate social responsibility (CSR) is an emerging field whose norms are still being written and rewritten. The concept of CSR as we know it today¹ started in the United States in the 1970s and 1980s and slowly spread to other developed countries in the 1980s and 1990s. The French for corporate social responsibility is Responsabilité sociale de l'entreprise (RSE), a nearly literal translation which however diverges to some extent from the original English. The concept is still unclear despite having been the subject of an increasing number of academic and professional papers, in management as well as in law journals. In the present study, we shall use the definition as set by the European Commission (2001), which defines it as ‘a concept whereby companies integrate social and environmental concerns in their business operations and in their interaction with their stakeholders on a voluntary basis’. The European Commission in its Communication to the Parliament (2006) has stressed the fact that ‘it is about enterprises deciding to go beyond minimum legal requirements and obligations (our emphasis) stemming from collective agreements in order to address societal needs’. The second part of the definition is often omitted, but is at the crux of the problem of determining where CSR begins and ends. Corporate practices which involve ethical, social or environmental problems are defined as CSR practices only if companies go above and beyond their legal obligations. It should also be noted that the definition does not specify which guidelines to take into account in order to identify the standards to be applied in any given circumstances.

The purpose of this paper is to compare different powder metallurgy (PM) processes to produce ceramic parts through additive manufacturing (AM). This creates the potential to rapidly shape ceramic parts with an almost unlimited shape freedom. In this paper, alumina (Al₂O₃) parts are produced, as Al₂O₃ is currently the most commonly used ceramic material for technical applications.

Variants of the following PM route, with indirect selective laser sintering (indirect SLS) as the AM shaping step, are explored to produce ceramic parts: powder synthesis, indirect SLS, binder removal and furnace sintering and alternative densification steps.

Freeform-shaped Al₂O₃ parts with densities up to approximately 90 per cent are obtained.

The resulting Al₂O₃ parts contain inter-agglomerate pores. To produce higher-quality ceramic parts through indirect SLS, these pores should be avoided or eliminated.

The research is innovative in many ways. First, composite powders are produced using different powder production methods, such as temperature-induced phase separation and dispersion polymerization. Second, four different binder materials are investigated: polyamide (nylon-12), polystyrene, polypropylene and a carnauba wax – low-density polyethylene combination. Further, to produce ceramic parts with increased density, the following densification techniques are investigated as additional steps of the PM process: laser remelting, isostatic pressing and infiltration.

The purpose of this study is the numerical investigation of densification and molding processes of wood. Providing theoretical and numerical approaches with respect to a consistent multi-physical finite element method framework are further goals of this research.

Constitutive phenomenological descriptions of the thermo-mechanical and moisture-dependent material characteristics of wood are introduced. Special focus is given to a consistent hygro-thermo-mechanical modeling at finite deformations to capture the realistic material behavior of wood, especially when it is subjected to densification and molding processes.

Realistic theoretical formulations of different hygro-thermo-mechanical processes are provided. A successful numerical modeling is demonstrated for beech wood by validation at experimental findings.

The constitutive laws and numerical findings are new, as they govern a multi-physical large deformation framework and are applied to the advanced technology of densification and molding of wood.

This study aims to investigate the initial corrosion behavior in aqueous solution of 20# seamless steel under (CO₂/aqueous solution) gas–liquid two-phase stratified flow conditions.

The initial corrosion behavior was studied through the weight loss methods, scanning electron microscopy with energy-dispersive x-ray spectroscopy and x-ray diffraction.

The corrosion rate of 20# steel obviously increases with the increasing gas pressure at different corrosion time when the CO₂ pressure is less than 0.11 MPa, and the increase of corrosion rate tends to be steady when the pressure exceeds 0.11 MPa. With the increase of CO₂ pressure, the corrosion products changed from flocculent to acicular, granular and scaly. A four-stage model for the growth of the corrosion product layer was proposed, namely, the diffusion reaction stage, the local film formation stage, the complete film formation stage and the densification stage of the product film.

A four-stage model for the growth of the corrosion product layer on the pipe wall surface under this condition was proposed, namely, the diffusion reaction stage, the local film formation stage, the complete film formation stage and the densification stage of the product film. The growing process and densification mechanism of corrosion products layer were discussed.

This paper aims to report the production of 316L-1 Wt.% NiB cubes by using the selective laser melting (SLM) process. The laser used was pulsed, millisecond Nd:YAG system with maximum average power 100 W.

Densification under different processing conditions (pulse energy, average laser power, laser scan speed, powder layer thickness, pulse frequency) was investigated. Morphology, macro and microstructure of laser melted samples were characterized by digital camera images and by scanning electron microscope. Density of the cubes was determined by Archimedes method in water. Vickers microhardness of samples was determined under the load of 25 g. Corrosion behavior of 316L and 316L-NiB samples was conducted in 5 per cent HCl solution at the testing temperature of 20°C during 240 h.

Using laser power of ∼60-70 W, lower beam overlap and powder layer thickness of 200 µm, 3D cubical samples were obtained with significant balling in individual layers and an overall porosity being around 30 per cent. By increasing laser power to ∼80 W, with higher beam overlap and lower powder layer thickness of 100 µm, SLM parts with no balling and the presence of small pores of up to 4 per cent (20 Hz) and 9 per cent (40 Hz) were obtained. With further increase of laser power to 90 W, overall porosity rose to around 12 per cent. The addition of 1 Wt.% NiB to stainless steel negligibly lowered its corrosion resistance in 5 per cent HCl solution.

A part from 316L stainless steel with balling-free structure and good density was successfully obtained through pulsed-SLM process with the aid of 1 Wt.% of NiB addition. Aside from significant influence on the improved structure of cubes, NiB had a favorable effect on microhardness values while practically not affecting the corrosion resistivity of the base material in an aggressive surrounding.

Both the current long term telecommunication trends toward optical networking and the recent growth in information bandwidth have pushed the necessity for improved optical communications. Our fabrication approach, which leverages our expertise in solid freeform fabrication in conjunction with sol‐gel technology, has advantages over these other methods because of the inherent benefits of using a direct‐write philosophy, such as design flexibility and minimal post‐processing. However, fabrication of such novel optical components requires extensive knowledge of their light guidance capabilities. This paper shows the technical issues involved in both modeling and characterizing small optical components fabricated by locally densifying sol‐gels in a modified direct‐write process.

Lignite coal-fired power plants are the main electricity generators in the province of Saskatchewan, Canada. Although burning lignite coal to generate power is economical, it produces significant greenhouse gases making it a big challenge to Canada’s international commitment on emission reduction. However, abundant agricultural crops and sawdust produced in Saskatchewan put the province in a good position to produce and use agri-pellets as an alternative fuel to generate electricity. This study aims to conduct an economic and environmental analysis of the replacement of lignite coal by agri-pellets as the fuel for Saskatchewan’s coal-fired power plants.

The study estimates the economic and environmental costs and benefits of two alternative fuels for power plants. The economic analysis is based on the pellet production and transportation costs from farms to production sites and from the production sites to power plants. In the production process, biomass precursors are densified with and without additives to produce fuel agri-pellets with appropriate mechanical durability and high heating value per volume unit. The environmental analysis involves estimation of greenhouse gas emissions and their social costs for lignite coal and different types of agri-pellets under different scenarios for pellet production and transportation.

The results show that although the total cost of electricity is lower for coal than agri-pellets, the gap shrinks when social costs and specifically a carbon price of $50/tonne are included in the model. The cost of electricity in lignite coal-fired power plants would also be on par with agri-pellets-fired power plants if the carbon price is between U$68 and $78 per tonne depending on the power plant locations. Therefore, a transition from coal to agri-pellet fuels is feasible if a high-enough price is assigned to carbon. The method and the results can be generalized to other places with similar conditions.

There are a few caveats in this study as follows. First, the fixed costs associated with the transformation of the existing coal-fired power plants to pellet-fired plants are not considered. Second, the technological progress in the transportation sector, which would favor the net benefits of using pellets versus coal, is not included in the analysis. Finally, the study does not address the possible political challenges facing the transition in the context of the Canadian federal system.

The study results indicate that the current carbon price of $50 per tonne is not sufficient to make the agri-pellets a feasible source of alternative energy in Saskatchewan. However, if carbon pricing continues to rise by $15 annually starting in 2022, as announced, a transition from coal to agri-pellets will be economically feasible.

Canada is committed to reduce its emission according to the Paris agreement, and therefore, needs to have a concrete policy to find alternative energy sources for its coal-fired power plants. This study examines the challenges and benefits of such transition using the existing agri-pellet resources in Saskatchewan, a province with abundant agricultural residues and coal-fired power plants. The findings indicate that a significant emission reduction can be achieved by using agri-pellets instead of coal to produce electricity. The study also implies that the transition to renewable energy is economical when social costs of carbon (carbon tax) is included in the analysis.

As far as the authors know, this is the first study providing a socio-economic analysis for a possible transition from the coal-fired power plants to a more clean and sustainable renewable energy source in one of the highest carbon dioxide (CO₂) producer provinces in Canada: Saskatchewan. The study builds upon the technical production of three agri-pellets (oat hull, canola hull and sawdust) and estimates the economic and environmental costs of alternative fuels under different scenarios.

Submarine propeller shaft seals operate under onerous conditions in an aggressive environment and their effective life is vitally dependent upon the durability of the seal face materials. The combination of physical and mechanical properties of certain carbon‐carbon composites makes them potentially suitable for this critical service, but a literature search revealed no prior reference to their deployment in any liquid sealing application nor, indeed, to their behaviour in an aqueous environment. In consequence, a programme of work has been carried out to determine the effect of prolonged exposure to high‐pressure sea water upon their properties, and to assess their performance when run in a seal test rig against a variety of counter surfaces. The assessments were made under a reproducible condition of boundary lubrication stabilised by control of interface torque. The effects of composite anisotrophy and of graphitisation have been examined using specimen rings with the direction of fibre lay‐up either in, or normal to, the rubbing plane, and in the graphitised or non‐graphitised condition. It has been shown that the carbon‐carbon composites are stable in water and perform well as a seal face material; however, current high procurement cost will probably restrict their use to the more exacting applications.