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The purpose of this paper is to characterize the effects of different micro particle reinforcement with same weight ratio in acrylonitrile-butadiene-styrene (ABS) feed-stocks for 3D printing process.

In this study, composite filaments were produced by using a co-rotational twin screw extruder and used as building material to print samples in a commercial fused deposition modeling (FDM) 3D printer. The reinforcement particles, ZrB₂ and Al, have different properties, including density, surface area, purity and particle morphology, and were expected to improve mechanical properties of 3D printed samples. Differential calorimetry scanning and melt flow index studies were applied on the materials to observe the change in glass transition temperatures and melt flow behaviors, respectively. Also, to evaluate the mechanical properties, tensile and three-point bending test were carried out. Fractured surfaces were characterized via energy-dispersive X-ray spectroscopy for validation of the reinforcements in the ABS matrix. Moreover, scanning electron microscope micrograph examination was conducted on the fractured surfaces to characterize fracture modes.

For 3D printed samples, a strain increase of at least 82.5 per cent was achieved by using micro particle reinforcement with a weight ratio of 1.5 per cent.

Higher filler ratios of the reinforcement particles cause loss on the printability of the feed-stocks.

Reinforced ABS stands out as a possible solution to overcome robustness problems in FDM printing.

Even though the effects of printing parameters on the mechanical properties of 3D printed parts have been vastly studied in the literature, studies conducted on improvement of the building materials are limited. This paper proposes to create novel feed-stock materials for achieving printed parts with superior properties using polymer composites.

The purpose of this paper is to improve the wear resistance and tribological properties of magnesium and its alloys in order to apply them to the friction components.

Wear test, microhardness measurements, X‐ray diffraction (XRD), optical and electron microscopy examinations were applied.

The ceramic SiO₂, which has different particle‐sized reinforced pure Mg‐SiO₂ composites, is produced by powder metallurgy using high ball milling, pressing and sintering. Mg₂Si and MgO intermetallic phases produced by powder metallurgy in the Mg‐SiO₂ composite are dispersed as homogeneous into the Mg matrix. Mg‐SiO₂ composites exhibited a lower wear rate than the unreinforced pure magnesium specimens. Despite the pure Mg, the wear resistance of the composite is 61 per cent and the wear volume decrease with reducing SiO₂ particle size. The hardness of the composite is increased in a ratio of 70 per cent with the distribution of the Mg₂Si and MgO phases into the Mg matrix.

In this paper, pure Mg powder with purity of 99.9 per cent and SiO₂ powders with a mean particle size of −500, −250, −125, −75 and −10 μm are mixed by mechanical alloying. The wear behaviour of Mg‐SiO₂ composite, with the different particle‐sized composites dispersed with Mg₂Si and MgO intermetallic phases under dry friction condition is studied. The microstructural and mechanical properties of composite material samples are determined by differential scanning calorimeter, XRD, microhardness, optical and scanning electron microscopy tests.

SiO₂ particles distributed in the matrix are effective to improve hardness and wear resistance when contacting counter materials. In the present study, the magnesium powders with different particle size SiO₂ powders are mechanically alloyed with a Turbola Spex 80000 mixer.

By drawing on 18-month ethnographic fieldwork conducted among people who participate in state-regulated games of chance in Istanbul, during the recent Turkish economic crisis in 2021–2022, and engaging with scholarly work on the anthropology of Turkey, economic anthropology and local media and grey resources, this article illustrates the rise of cryptocurrency trading in Turkey. This article shows how my participants situated the cryptocurrency trading within their own techniques to ameliorate financial volatility and to compensate their mistrust in governmental financial institutions during times of economic turbulence. Cryptocurrency trading was viewed as an investment technique that assists in accumulating savings for ensuring the future amid fluctuating national currency and polarized political realities. Meanwhile, cryptocurrency trading was also identified as a game of chance that swings between hinging on luck or skill, and the research participants debated if cryptocurrency trading is permissible in Islam (Halal) or forbidden. Therefore, this article suggests that cryptocurrency trading, although on the rise, is still a contested topic in which the boundaries between perceptions and practices of investing and gambling are blurred within the Turkish context. The controversy of the cryptocurrency trading emerges from the polarized public attitudes and the dissonance between traditional ideals, that condemn easy money and emphasize the value of hard work, in contrast to the neoliberal realities of capitalistic modes of accumulation that encourages speculation over production.

The Covid-19 pandemic spread rapidly around the world and required strict restriction plans and policies. In most countries around the world, the outbreak of the disease has been serious and has greatly affected the health system and the economy. The factors such as the number of patients with chronic diseases, the number of people over 65 years old, hospital facilities, the number of confirmed Covid-19 cases, the recovering Covid-19 cases and the number of deaths affect the rate of spread of Covid-19. This study aims to evaluate the performances of 21 Organisation for Economic Co-operation and Development (OECD) countries against the Covid-19 outbreak using three data envelopment analysis (DEA) models.

In this study, the performance of 21 OECD countries to manage the Covid-19 process has been analysed weekly via DEA which is widely used in various practical problems and provides a general framework for efficiency evaluation problems using the inputs and outputs of decision-making units.

The analysis showed that 11 countries out of 21 countries were efficient for selected weeks. According to the DEA results from the 20-week review (09 April 2020–20 August 2020), information about the course of the epidemic prevention and the normalization process for any country can be obtained.

In this study, due to the problem of the discrimination power of DEA, the cross-efficiency model and the super-efficiency model also used. In addition, the output-oriented model was preferred in this study for Covid-19 management efficiency.

The purpose of the study is to design a three-dimensional (3D) triglide parallel robot with a different approach and to control the manufactured robot via sliding mode control method that has not been applied to the robot before.

The x, y and z coordinates of the end effector of the robot have been given as a reference. The x, y and z reference values are transformed as new reference values of the vertical movement of the robot on the endless screw by using the inverse kinematic equations of the robot. The control of the robot over these reference values is provided by a sliding mode control. The MATLAB/real-time toolbox has been used for creating the interface. The real-time control of the triglide robot has been carried out with a sliding mode controller in the Simulink environment.

When the results of the sliding mode control are examined, it is seen that the desired reference values are provided in about 0.6 s. The velocity of the sliding limbs in each arm of the robot is approximately 50 mm/s. The reference values have been reached using the sliding mode control method, with an average error of 0.01 mm. In addition, the problem of chattering in the system caused by using the sign function has been relatively eliminated by using the saturation function instead of the sign function. Thus, the sliding mode control method with saturation function is more feasible.

In this study, the triglide parallel robot was manufactured using a 3D model after taking into consideration the dimensions of the 3D model. After production, the necessary hardware connections were provided, and a real-time sliding mode control method was implemented to the robot by using the interface program in MATLAB/Simulink environment. The literature contribution of the paper is the real-time control of the triglide robot with the sliding mode control method.

Treatment of intersectionality in empirical studies has predominantly engaged with individual categories of difference. The purpose of this paper is to demonstrate that there is utility in exploring intersectionality at the intersection of individual and institutional levels. As such the authors move beyond the polarised take on intersections as either individual or institutional phenomenon and tackle intersectionality as a relational phenomenon that gains meaning at the encounter of individuals and institutions in context. Therefore, the authors explicate how intersectionality features as forms of solidarity and hostility in work environments. As such the authors posit that not only individuals but also the institutions should change if inclusion is aimed at societal and organisational levels.

A thematic analysis on qualitative interview data of a purposive- and snowball-selected sample of 11 lesbian, gay, bisexual, transgender and queer working adults in Turkey was used.

This paper finds evidence to support the existence of a multidimensional model of intersectionality, where conflicting and complementary individual and institutional intersections create four intersectional typologies in the form of intersectional hostility, intersectional struggle, intersectional adjustment and intersectional solidarity.

The extant literature offers rich insights into individual intersectionality but sheds very little light on institutional intersectionality and its interaction with individual intersectionality. This paper attempts to fill in this gap by investigating intersectional encounters as interactions between the individual and institutional intersections.

Spaciousness is defined as “the feeling of openness or room to wander” that has been affected by various physical factors. The purpose of this paper is to assess the spaciousness of space to determine how spacious the space is. Furthermore, the study intends to propose a fuzzy-based model to assess the degree of spaciousness in terms of physical parameters such as area, proportion, the ratio of window area to floor area and color value.

Fuzzy logic is the most appropriate mathematical model to assess uncertainty using nonhomogeneous variables. In contrast to conventional methods, fuzzy logic depends on partial truth theory. MATLAB Fuzzy Logic Toolbox was used as a computational model including a fuzzy inference system (FIS) using linguistic variables called membership functions to define parameters. As a result, fuzzy logic was used in this study to assess the spaciousness degree of design studios in universities in the Iraqi Kurdistan region.

The findings of the presented fuzzy model show the degree to which the input variables affect a space perceived as larger and more spacious. The relationship between parameters has been represented in three-dimensional surface diagrams. The positive relationship of spaciousness with the area, window-to-floor area ratio and color value has been determined. In contrast, the negative relationship between spaciousness and space proportion is described. Moreover, the three-dimensional surface diagram illustrates how the changes in the input values affect the spaciousness degree. Besides, the improvement in the spaciousness degree of the design studio increases the quality learning environment.

This study attempted to assess the degree of spaciousness in design studios. There has been no attempt carried out to combine educational space learning environments and computational methods. This study focused on the assessment of spaciousness using the MATLAB Fuzzy Logic toolbox that has not been integrated so far.

The Covid-19 pandemic highlighted the contradictions inherent to balconies. Despite the attention given to these architectural elements on that moment, there is a knowledge gap concerning the preferences and expectations of the inhabitants in relation to them. For this reason, this paper aims to conduct a critical literature review of the publications about the inhabitants’ perceptions of balconies in order to identify the most relevant criteria to consider during the design process.

The analysis was based on the post-occupancy evaluation (POE) criteria (technical, functional and behavioural).

The results highlighted the relevance of the behavioural criteria for the valorisation of the balconies by the inhabitants and presented indications to the research about these liminal spaces and the design practice of housing buildings.

According to the authors’ best knowledge, this study represents the more holistic study of the kind.

We examine the relationships among leader spirituality, organizational innovativeness, transformational leadership style and project success. Integrating principles of behavioral learning and social learning theories, we argue that spiritual leadership style is positively linked to project success, and this relationship is mediated by transformational leadership. Furthermore, the relationship between leader spirituality and transformational leadership is moderated by organizational innovativeness.

Data are collected from 180 individuals working in seven large project-based organizations from the telecom sector in Pakistan. The individuals comprise engineers, functional managers, dedicated project managers and individuals who have led and/or worked in project teams. Data are analyzed using variance-based structural equation modeling.

Results suggest that the relationship between spiritual leadership style and project success is positive and is partially mediated by transformational leadership. Furthermore, organizational innovativeness positively moderates the spiritual leadership and transformational leadership relationship.

Research calls for examining the relationship between leadership styles and project success. We address this call through examining the role of spiritual leadership style (which is rather ignored in project management literature) for project success. Furthermore, we take a novel evolutionary approach of integrating different leadership styles and indicating determinants as well as contingencies to leadership development.