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Epoxy resins are widely used in a variety of engineering applications, including composite wind turbine blades used in the renewable energy industry, highly complex structural components for aircraft, paints, coatings, industrial tooling, biomedical systems, adhesives, electronics and automotive. Epoxies' low fracture toughness is one of the key obstacles preventing its adoption in a wider range of applications. To address epoxy's low fracture toughness, this paper aims to examine the roles of intra-ply hybridization and nano reinforcing.

This paper investigates the role of intra-ply hybridization of glass-carbon woven fibers and adding 0.8 wt.% of multiwall carbon nanotube (MWCNT) nano reinforcement to overcome the low fracture toughness of epoxy. A bending test is used to calculate the composites elastic parameters, and a notched sample three-point bending test is used to show crack behavior in addition to using materials characterization methods to reveal the effect of the MWCNT on structure, bonding, glass transition temperature (Tg) and dispersion of MWCNT in the matrix. Furthermore, this paper suggests using the finite element method to overcome the difficulty in calculating the crack extension.

Intra-ply hybridization and MWCNT reinforcement decrease the crack extension of epoxy with time. The inclusion of high-strength carbon fiber increased the fracture toughness of glass composite. Furthermore, the existence of MWCNT in the surrounding area of the notch in epoxy composites hinders crack propagation and provides stiffness at the interface by bridging the crack and eventually enhancing its fracture toughness.

Studying the role of intra-ply hybridization of glass-carbon woven fibers and adding 0.8 wt.% of MWCNT nano reinforcement to overcome the low fracture toughness of epoxy. Additionally, this research recommends using the finite element method to overcome the challenge of computing the crack extension.

The paper aims to design the optimum formulation of the nano-titanium dioxide (TiO2) hydrophilic coating system using the synthetic polypropylene glycol (PPG), which can create the reflection and absorption property.

TiO2 nanoparticles are used as fillers, and PPG has been blended at the proper ratio of 1PPG: 0.2TiO2. The prepared resin has been applied onto the glass substrate at different numbers of glass immersions during the dip-coating fabrication process. One-time glass immersion is labeled as T1 coating, two-time glass immersion is labeled as T2 coating and three-time glass immersion is labeled as T3 coating. All the prepared coating systems were left dry at ambient temperature.

T3 coating showed the lowest reading of WCA value at 40.50°, due to higher surface energy at 61.73 mN/m. The T3 coating also shows the greatest absorbance property among the prepared coating systems among the prepared coating. In terms of reflectance property, the T2 coating system has great reflectance in UV region and near-infrared region, which is 16.47% and 2.77 and 2.73%, respectively. The T2 coating also has great optical transmission about 75.00% at the visible region.

The development of thermal insulation coating by studying the relationship between convection heat and reflectance at different wavelengths of incident light.

The developed coating shows high potential for glass window application.

The application of the hydrophilic coating on light absorption, reflectance and transmission at different wavelengths.

The purpose of this study is to look into the hygroscopic and tribo-mechanical properties of a polypropylene/polyamide-6 (PP/PA6) blend and a PP/PA6/Boron sesquioxide composite.

The hygroscopic behaviour of the PP/PA6 blend and PP/PA6/Boron sesquioxide composite was studied using a water contact angle goniometer in this study. To validate the hygroscopic behaviour of the blend and composite, water contact angles and surface energy of the materials were investigated. Tensile strength and hardness tests were used to determine mechanical characteristics, and tribological experiments on a pin-on-disc tribometer were used to demonstrate the friction and wear rates of dry and water-conditioned blends and composites. The melting temperature of dry and water-conditioned composites was determined using DSC analysis.

The hygroscopic effect of the PP/PA6 blend was found to be minimal in the experiment, while it was relatively dominating in the PP/PA6/Boron sesquioxide composite. Tensile strength was found to be somewhat lower in blend and composite compared to virgin PP, whereas hardness was found to be higher in both blend and composite. The composite’s tribological testing findings were fairly outstanding, with the coefficient of friction (COF) and wear rates significantly reduced due to boron sesquioxide reinforcement. The reaction between boron sesquioxide and water molecules produced boric acid, which increased the tribological characteristics of the composite even further. Following 30 days of water conditioning, the weight of the blend increased by 3.64% and the weight of the composite increased by 6.45% as compared to the dry materials. After water conditioning, tensile strength reduced by 0.8% for the blend and 14.16% for the composite. Hardness was determined to be the same in the dry state and after water-conditioning for blend but dropped 1% for composite. As compared to blend, the COF and wear resistance of composite were 15.52% and 25.16% higher, respectively. After absorbing some water, the results increased to 28.57% and 34.9%, respectively.

The mechanical and thermal behaviour of polymer composites (particularly polyamide composites) vary depending on the surrounding environment. Tests were carried out to explore the effect of water treatment on the tribo-mechanical and thermal characteristics of PP/PA6/Boron sesquioxide composite. Water treatment caused polyamides to bind with water molecules, resulting in voids in the material. The interaction between boron sesquioxide and water molecules produced boric acid, which increased the tribological characteristics of the composite.

Comfortable outdoor workspaces are important for employees in business parks and urban areas. Prioritizing a pleasant thermal environment is essential for employee productivity, as well as the improvement of outdoor spaces between office buildings to enhance social activities and quality of outdoor workplaces in a hot arid climate has been subjected to very little studies Thus, this study focuses on business parks (BPs) landscape elements. The objective of this study is to enhance the user's thermal comfort in the work environment, especially in the outdoors attached to the administrative and office buildings such as the BPs.

This research follows Four-phases methodology. Phase 1 is the investigation of the literature review including the Concept and consideration of BP urban planning, Achieving outdoor thermal comfort (OTC) and shading elements analysis. Phase 2 is the case study initial analysis targeting for prioritizing zones for shading involves three main methods: social assessment, geometrical assessment and environmental assessment. Phase 3 entails selecting shading elements that are suitable for the zones requiring shading parametrize the selected shading elements. Phase 4 focuses on the optimization of OTC through shading arrangements for the prioritized zones.

Shading design is a multidimensional process that requires consideration of various factors, including social aspects, environmental impact and structural integrity. Shading elements in urban areas play a crucial role in mitigating heat stress by effectively shielding surfaces from solar radiation. The integration of parametric design and computational optimization techniques enhances the shading design process by generating a wide range of alternative solutions.

While conducting this research, it is important to acknowledge certain limitations that may affect the generalizability and scope of the findings. One significant limitation lies in the use of the shade audit method as a tool to prioritize zones for shading. Although the shade audit approach offers practical benefits for designers compared to using questionnaires, it may have its own inherent biases or may not capture the full complexity of human preferences and needs.

Few studies have focused on optimizing the type and location of devices that shade outdoor spaces. As a result, there is no consensus on the workflow that should regulate the design of outdoor shading installations in terms of microclimate and human thermal comfort, therefore testing parametric shading scenarios for open spaces between office buildings to increase the benefit of the outer environment is very important. The study synthesizes OTC strategies by filling the research gap through the implementation of a proper workflow that utilizes parametric thermal comfort.

The objective of this study is to determine how biophilic designs in study areas affect the productivity of students at the University of the Witwatersrand. The study also seeks to evaluate study areas at Wits in terms of biophilic design, determine whether biophilic design contributes to the preference of students and their study productivity.

This is a cross sectional study that used a mixed methodology. Five study areas were identified and evaluated in terms of biophilic design. At each study area, nine students participated in an open- and close-ended questionnaire regarding their perceptions on study areas and productivity.

The five study areas scored the following results according to the biophilic test: 29.09%, 34.55%, 36.36%, 80.00% and 85.45%, respectively. The students prefer to study in biophilic study areas as it prompts positive emotions and make them feel rejuvenated and energized. However, there are still students studying in the non-biophilic areas due to convenience or due to the biophilic areas that are noisy and lacks monitoring.

With the small sample size, the generalizability of the findings are limited, but does create a foundation for further research.

Universities can learn from the findings and benefit greatly from many biophilic study areas. This could also encourage architects and interior designers to include biophilic design more so in general buildings/rooms.

Study areas at the University of the Witwatersrand was evaluated in terms of biophilic design, while determining whether biophilic design contributes to the preference of students and study productivity.

Drawing upon the framework of social exchange theory, this study investigated the influence of work-life balance, procedural justice and distributive justice on job satisfaction and turnover intention among Vietnamese millennials.

Employing a quantitative research method, the authors collected a sample of 258 millennial participants in Vietnam. Utilizing the method of multiple regression analysis, the collected data were rigorously examined.

The results showed that job satisfaction is negatively related to the turnover intention of the millennial generation in Vietnam. Distributive justice is a stronger predictor of job satisfaction than procedural justice. Of particular note, the study revealed an intriguing result: work-life balance does not have a significant influence on job satisfaction among millennials.

Leveraging insights from national cultural theories, the authors' findings provide some insightful explanations of what drives millennials in Vietnam to consider leaving their organizations.

The study provides some insights for policymakers in Vietnam and other similar developing countries to reform their approach at managing the millennial generation.

The research addresses the existing gap in literature by delving into the underlying factors driving the propensity of Vietnamese millennials to frequently switch jobs.

This study aims to develop and test a model of the antecedents, mediators and consequences of the glass cliff phenomenon through public sector service organizations in Iran to explore more insights on gender inequality in managerial positions.

The current research was conducted based on a mixed-method approach, using both qualitative and quantitative research designs. First, the qualitative method includes content analysis by conducting semi-structured interviews with 20 university professors and expert managers working in public sector service organizations in Iran. The outcomes of the qualitative phase lead to designing the conceptual framework and research hypothesis. Then, through a quantitative phase, 384 female managers working in public sector service organizations in Iran are selected using stratified random sampling and fill out the research questionnaire. The exploratory factor analysis was used to verify the model. Moreover, structural equation modeling, using AMOS 24, was used to test the research hypothesis.

The findings of the qualitative phase were represented in three categories including antecedents (e.g. the characteristics of women’s leadership, the selection of women based on meritocracy criteria, women’s preferences and organizational factors), mediation effect (e.g. succession planning, personal development planning and support networks) and consequences of the glass cliff phenomenon (e.g. positive and negative consequences). The results of the exploratory factor analysis show there are ten components, explaining 88.5% of variances. Moreover, the test of the structural model supports the direct effect of antecedents on the glass cliff phenomenon. The results also show the effect of the glass cliff phenomenon on consequences through mediation effects.

There are some limitations that can be addressed by other researchers. Accordingly, the limited number of female managers in Iran prevented larger quantitative research. Moreover, the current research only found casual and mediation consequences of the glass cliff phenomenon, and potential moderators were not considered in this study.

The present study’s innovations may include using a mixed-method approach to investigate the antecedents, mediators and consequences of the glass cliff phenomenon in this study and examining the model constructs in some public sector service organizations. This research may provide a deep understanding of the antecedents, mediators and consequences of the glass cliff phenomenon by finding new factors using a mixed-method approach.

The aim of this study is to determine the fracture behavior of wool felt and fabric based epoxy composites and their responses to electromagnetic waves.

Notched and unnotched tensile tests of composites made of wool only and hybridized with a glass fiber layer were carried out, and fracture behavior and toughness at macro scale were determined. They were exposed to electromagnetic waves between 8 and 18 GHz frequencies using two horn antennas.

The keratin and lignin layer on the surface of the wool felt caused lower values to be obtained compared to the mechanical values given by pure epoxy. However, the use of wool felt in the symmetry layer of the laminated composite material provided higher mechanical values than the composite with glass fiber in the symmetry layer due to the mechanical interlocking it created. The use of wool in fabric form resulted in an increase in the modulus of elasticity, but no change in fracture toughness was observed. As a result of the electromagnetic analysis, it was also seen in the electromagnetic analysis that the transmittance of the materials was high, and the reflectance was low throughout the applied frequency range. Hence, it was concluded that all of the manufactured materials could be used as radome material over a wide band.

Sheep wool is an easy-to-supply and low-cost material. In this paper, it is presented that sheep wool can be evaluated as a biocomposite material and used for radome applications.

The combined evaluation of felt and fabric forms of a natural and inexpensive reinforcing element such as sheep wool and the combined evaluation of fracture mechanics and electromagnetic absorption properties will contribute to the evaluation of biocomposites in aviation.

This paper will challenge normative disaster studies and practice by arguing that thriving communities require the pursuit of imperfection and solidarity. The authors use Lewis Carroll’s Looking-Glass World as a lens to critique both how disasters are understood, and how disaster researchers and practitioners operate, within a climate-change affected world where cultural, political and historical constructs are constantly shifting.

The paper will undertake an analysis of both disasters and disaster studies, using this unique (and satirical) critical lens, looking at the unfolding of systemic mistakes, oppressions and mal-development that are revealed in contemporary disasters, that were once the critiques of Lewis Carroll’s Victorian-era England. It shows how disaster “resilience-building” can actually be a mechanism for continuing the status quo, and how persistent colonizing institutions and systems can be in reproducing themselves.

The authors argue the liberation of disaster studies as a process of challenging the doctrines and paradigms that have been created and given meaning by those in power – particularly white, Western/Northern/Eurocentric, male power. They suggest how researchers and practitioners might view disasters – and their own praxis – Through the Looking Glass in an effort to better understand the power, domination and violence of the status quo, but also as a means of creating a vision for something better, arguing that liberation is possible through community-led action grounded in love, solidarity, difference and interconnection.

The paper uses a novel conceptual lens as a way to challenge researchers and practitioners to avoid the utopic trap that wishes to achieve homogenized perfection and instead find an “imperfect” and complex adaptation that moves toward justice. Considering this idea through satire and literary criticism will lend support to empirical research that makes a similar case using data.

The main aim of the current study is to investigate the effect of Anti-Crack HP 67/36 glass fibre on the mechanical performance of mortars made of cement, with a focus on post-cracking evaluations using the digital image correlation (DIC) technique.

Experimental tests were carried out on 36-mm long fibres at 0.8% by volume and added to the normal strength (NSM), high strength (HSM) and high strength mortar with fly ash (HSMFA) mortars. CEM I 52.5 CP2 NF, CEM II/A-L 42.5 NF and CEM III/C 32.5 N-SR PM were used for each series of mortar to assess the performance of the glass fibres with the types of cement. F-class fly (FA) ash was used to reduce global CO₂ emissions.

The mortar’s strength decreased as the cement types changed from CEM I to CEM II and III. However, due to changes in the portlandite content of the cement, water porosity increased for both types of mortar, without and with fibre. It was also found that using glass fibre increased flexural strength more than compressive strength, regardless of the type of cement used. For all the strength classes, it was found that the mortar mixes with CEM I had the highest critical crack opening (w_c) and fracture energy (G_F), followed by CEM II and III. No significant effects were observed in the mortar’s property by replacing fly ash (12%).

Only mortars were formulated in this study, but the results must be verified at the concrete scale.

Validation of the DIC technique to characterize the post-cracking behaviour of cement-based material. Use of glass fibres to improve the material’s resistance to cracking.

Use of CEM II and CEM III cements with low CO₂ footprint instead of CEMI without altering the mechanical performance of the material.

The work is a further contribution to studying the cracking behaviour of several series of variable mortars depending on the resistance class and the type of cement used.