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This paper aims to investigate the impacts of introducing voids combinations on natural ventilation performance in high-rise residential building living unit.

This study was carried out through field measurement and computational fluid dynamics methods. The parameters of the study are void types and sizes, and a wind angle was used to formulate case studies.

The results indicate that the provision of a single-sided horizontal void larger by 50% increase the indoor air velocity performance up to 322.37% to 0.471 m/s in the living unit and achieves the required velocity for thermal comfort.

Passive design features are the most desirable techniques to enhance natural ventilation performance in the high-rise residential apartments for thermal comfort and indoor air quality purposes.

The paper aims to investigate and evaluate the impacts of the voids combination as a passive design feature on wind-driven ventilation performance in high-rise residential building units. It proposes a series of building models and thereon indoor ventilation performance and outlining why and how these building models designed with architectural design features are important. This study aims to provide a comprehensive understanding of how natural ventilation as a passive cooling strategy in living units of high-rise residential buildings can be applied through improving the provision of the architectural design feature of voids configurations.

The study was carried out through field measurements experiment and the computational fluid dynamics methods. A series of numerical simulations were carried out to calculate the indoor ventilation rate inside the case studies of the generated building models based on various variables such as horizontal voids type, size and wind directions.

The results indicate that the provision of a single-sided horizontal voids in building models can improve the indoor ventilation rate in units with cross ventilation mode up to 4 times, depending on wind direction and living unit location. The indoor ventilation performance in units located in models with single-sided horizontal voids is 17.54% higher than the units located in models without voids configuration. Furthermore, higher indoor ventilation performance was achieved in the case scenarios located at higher levels compared to the middle and lower levels in both horizontal voids types.

This study explores the application of voids combinations for natural ventilation performance, investigates the numerical simulation results and validates field measurements experiment data using CFD simulation.

The aim of this article is to understand the definitions, trends and gaps currently existing in the literature regarding the concept of void in the built environment.

The method used for this article is based on a bilingual narrative literature review, the authors being fluent both in French and English. The advantage of any literature review is that it allows researchers to gather and analyse existing academic literature on a specific subject. The chosen technique gives a thorough understanding of the study and helps in identifying research gaps. The literature review was sequential, online and used ScienceDirect, Scopus and Sage Knowledge as databases.

There are three main findings regarding this literature review. The first shows that the void is lacking consensus regarding its definition and attributes, yet this is unanimously considered as an existing space in the city. The second finding shows that voids are talking to our emotions and perceptions and more studies could investigate a new planning/design approach in taking this into consideration. At last, the third findings shows that there are some gaps that need to be further researched, such as the difference between Western and Eastern cultures to use voids in architecture.

In compiling 35 articles focussing on the void, this article proposes a valuable source of knowledge regarding this topic, as well as delineates new research directions.

While digital labour platforms are being increasingly studied across the Global South, the existing literature does not conceptualise the theoretical link between such platforms and socio-economic development. This paper theorises such a link drawing on the notion of institutional voids defined, as in Khanna and Palepu (2010), as “the absence of intermediaries to efficiently connect buyers and sellers” in an economy. We frame digital labour platforms as means to fill institutional voids, seeking to create “development” in the form of earning opportunities in contexts of deprivation.

We draw on an interpretive case study of an online work training project in a deprived region of Pakistan, where members of marginalised communities were trained to become freelancers for global digital labour platforms. We use the notion of market-enabling institutions aimed at filling institutional voids as a lens to study the project's declared goals, examining the extent to which these were met in practice for the workers who participated in the training.

Our analysis reveals three types of market-enabling institutions–credibility enhancers, aggregators and distributors, and transaction facilitators–through which digital labour platforms seek to fill institutional voids. However, workers' narratives reveal that institutional voids are only partially filled by these platforms, and their perpetuation results in diverse forms of power asymmetries leveraged by clients and owners of the platforms. We also observe the formation of solidarity networks among workers, networks that are intra-familial and societal rather than characterised by formal unionisation.

The paper offers a novel perspective to theorise the link between digital labour and socio-economic development. Applying such a perspective in a Global South context, it also finds the limits of the digital platforms' institutional void-filling potential, highlighting the emergence of power asymmetries and the emerging formation of worker solidarity networks.

Recent findings from a monitor containing around 1.5 million homes in the Dutch non-profit rental sector show that the improvement of the energy performance of the respective homes is mostly carried out in small steps: single measures per dwelling dominate and deep energy renovations are rare. From the way in which housing providers conceive and implement their portfolio and asset management strategies, the purpose of this paper is to explain for the dominance of the small interventions and investigate the argument for a more concentrated allocation of budget resources.

In total, 12 housing providers with different energy investment policies were selected and interviewed.

Results show that energy investments, as most other investments, must fit in regular investment schemes and have to follow general decision criteria such as the lifespan of the respective building element and the market position of the respective dwelling. As these schemes are limited in budget and time, the room for a more concentrated allocation of budget resources is small.

The number of organisations interviewed is obviously not statistically representative, but gives a good indication of the investment planning practice in the Dutch non-profit housing sector.

Much has been written about the (slow) progress of the energy performance in the housing sector, but not about the more structural organisational forces behind this progress.

MAGNESIUM metal with its low density high strength and stiffness properties is a material which is used extensively in the Wessex helicopter for castings, forgings, and in sheet form in the skin stringer constructed fuselage. Extensive utilisation of these aircraft has shown that a corrosion hazard is present with this material in the fuselage application. Accidental damage, mis‐use and normal wear and tear removes the carefully applied organic protection permitting moisture to come into contact with the non‐protected metal, with the result that corrosive conditions are generated and it is found that in the non‐accessible areas, intensive corrosion damage occurs and it is not discovered in time for remedial action and the efficiency of the structure and airframe is impaired.

This paper aims to evaluate the corrosion behavior of Ti-6Al-4V parts produced with electron beam melting (EBM) machine and compare it with wrought Ti-6Al-4V alloy.

Potentiodynamic and potentiostatic tests were applied on EBM Ti-6Al-4V in 3.5 per cent mass NaCl solution to determine the pitting potential and critical pitting temperature (CPT). A relation between pitting potential and temperature was established for EBM Ti-6Al-4V alloy by conducting potentiodynamic testing under different temperatures. CPT was also measured for EBM Ti-6Al-4V alloy in 3.5 per cent mass NaCl solution at a standard potential of 800 mV vs saturated calomel electrode (SCE). The same tests were performed on wrought Ti-6Al-4V for comparison purposes. Moreover, CPT for EBM Ti-6Al-4V alloy was measured in 3.5 per cent mass NaCl solution of different pH of 2.0, 5.7 and 10.0 to examine the effect of aggressive conditions on the pitting corrosion of EBM alloy.

Potentiodynamic test resulted in a relatively high pitting potential of EBM alloy, which was close to the pitting potential of wrought alloy even at higher temperatures. In addition, EBM samples did not pit when potentiostatic test was performed at 800 mV vs SCE, even at high and low values of pH.

EBM Ti-6Al-4V alloy has been increasingly playing an important role in aerospace, automobile and industrial fields. The technique and conditions of manufacturing form voids and increase roughness of the exterior surface of EBM objects, which might increase the tendency to initiate pitting corrosion within its holes and surface folds. This article shows that, despite surface variations and porosity in EBM Ti-6Al-4V alloy, the material maintained its corrosion resistance. It was found that the corrosion behavior of EBM alloy was close to that of the conventionally made wrought Ti-6Al-4V alloy.

The purpose of this paper is to examine the quality of the turned surface. The quality of the surface produced depends on the nature of the chips, which are produced while turning metal matrix composites. This quality is a function of the machining parameters, tool material, tool configuration and elements of the composites.

In this study, the turning of AA7075/15 wt.% SiC (particle size 20–40 µm) composites is investigated. Thirty experiments were conducted, and the chip-formation mechanism in turning AA7075/SiCp composites at various combinations of cutting speeds, feed and depth of cuts was studied.

It is observed from the response surface methodology-based experimentation that in turning of coarser reinforcement (particle size 20–40 µm) composites, total gross fracture occurs. This causes small slices of chips and a higher shear plane angle. The nature of chips produced at various combinations of cutting speeds, feed and depth of cuts is different. The chips generated were segmented, spiral in cylindrical form, connected C type, chips with saw tooth, curled chips, washer C type chips, half-curved segmented chips and small-radii segmented chips.

The novelty of this research is that, so far, very little work has been published on the detailed analysis of chips produced during turning of AA7075/15 wt.% SiC (particle size 20–40 µm) composites.

This study aims to outline the current challenges in ultrasonic additive manufacturing (AM). AM has revolutionized manufacturing and offers possible solutions when conventional techniques reach technological boundaries. Ultrasonic additive manufacturing (UAM) uses mechanical vibrations to join similar or dissimilar metals in three-dimensional assemblies. This hybrid fabrication method got attention due to minimum scrap and near-net-shape products.

This paper reviews significant UAM areas in process parameters such as pressure force, amplitude, weld speed and temperature. These process parameters used in different studies by researchers are compared and presented in tabular form. UAM process improvements and understanding of microstructures have been reported. This review paper also enlightens current challenges in the UAM process, process improvement methods such as heat treatment methods, foil-to-foil overlap and sonotrode surface roughness to increase the bond quality of welded parts.

Results showed that UAM could solve various problems and produce net shape products. It is concluded that process parameters such as pressure, weld speed, amplitude and temperature greatly influence weld quality by UAM. Post-weld heat treatment methods have been recommended to optimize the mechanical strength of ultrasonically welded joints process parameters. It has been found that the tension force is vital for the deformation of the pre-machined structures and for the elongation of the foil during UAM bonding. It is recommended to critically investigate the mechanical properties of welded parts with standard test procedures.

This study compiles relevant research and findings in UAM. The recent progress in UAM is presented in terms of material type, process parameters and process improvement, along with key findings of the particular investigation. The original contribution of this paper is to identify the research gaps in the process parameters of ultrasonic consolidation.

The purpose of this paper is to contextualise and assess “controlled” evidence about emerging plural provision of social housing within an English region.

Two matching pairs of case study social housing provider type (stock transfer associations and arm's‐length management organisations), all established between four and seven years previously and all located within the same region, are compared and contrasted through rich qualitative interviews with stakeholders, backed by secondary and other documentary evidence.

The new models have led to considerable change for both staff and tenants across many dimensions, mainly positive, in service delivery terms. It is also apparent that regulation and inspection have a dominant impact on social providers. It can be inferred from the evidence that a key challenge for the future is the lack of a clear, long‐term vision for social housing at the national policy level.

The paper is a rare empirical examination of wide‐ranging change to social housing in the UK. It is also unusual in its attempt to construct a quasi‐experimental series of case studies.