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Punching can trigger catastrophic failures in flat slabs because of its sudden nature resulting from exceeding the shear capacity of slabs. Effect of using recycled aggregate, as an environmental-friendly alternative to traditional RC structures, on punching behavior of these slabs was not sufficiently investigated in the literature. Hence, this paper aims to experimentally study the effect of using recycled coarse aggregate (RCA) on the punching shear capacity (PSC) of RC flat slabs. The RCA is produced by crushing of waste of concrete standard cubes obtained from compression tests.

A total of 12 slab-column connection specimens with different slab thicknesses (140, 160 and 200 mm) and different RCA percentages (0%, 30% and 70%) were prepared and tested under a central point load, to test its effect on the behavior of flat slabs. The punching failure loads of the tested specimens were compared with those obtained according to the provisions of different international building codes.

Compared with natural aggregate concrete, mixes with 30% and 70% RCA experienced reductions in the compressive that did not exceed 4% and 21%, while reductions of 4% and 13% were observed for the tensile strength, respectively. The increase in the amount of RCA reduced the PSC by 0%–7%, 0%–4% and 4%–10% for slabs with a thickness of 140, 160 and 200 mm, respectively. For slabs with punching shear reinforcement (PSR), ACI 318 provided the closest estimation for the PSC by 9%, whereas EURO 2 overestimated the PSC by 25% and ECP 203 underestimated the PSC by 41%.

The provided conclusions are obtained from the conducted experimental work where a constant W/C ratio, aggregate type and a maximum aggregate size of 19 mm for the RCA were adopted.

Enhancement in the behavior of flat slabs with various thicknesses and amounts of RCA because of introducing PSR is experimentally evaluated. The failure loads of the tested slabs with recycled and normal coarse aggregates were compared against different code provisions.

This paper aims to estimate the bearing capacity of a surface strip and circular footings lying on layered sand using numerical limit analysis.

Lower and upper bound limit analysis, as well as finite elements and second-order conic programming (SOCP), are used in this analysis. The yield criterion of Mohr-Coulomb is used to model soil behavior. Using this technique, stringent lower and upper bounds on ultimate bearing capacity can be achieved by assuming an associated flow law.

The obtained results indicate that the exact collapse load is typically being bracketed to within 6% about a mean of both the bounds. The obtained results are compared with the existing literature wherever applicable.

To the best of the authors’ knowledge, no study has used lower and upper bound limit analysis, as well as finite elements and SOCP, to estimate the bearing capacity of a surface strip and circular footings lying on layered sand.

This study is concerned with the dynamics of the internal communications at Netflix following the release of The Closer and the public debate that followed, testing Netflix's long-standing reputation for promoting diverse content and supporting a progressive organizational culture.

Using the circuit of culture (CoC) as a theoretical framework, this study applies a case study approach to analyze internal communication and strategic public relations in addressing this crisis.

This study's findings illustrate that by failing to interpret two of the five moments of the CoC, production and identity, Netflix negated the very values that constitute its brand. These findings have implications for how public relations' long-standing focus on two-way symmetrical communication is problematic, especially in the workplace.

The findings situate how the exertion of power within an organization, particularly in moments of identity and production, problematize the role of two-way symmetrical communication within an organization in crisis.

In recent years, additive manufacturing (AM) has started to be used for manufacturing real functional parts and assemblies for critical applications in aerospace, automotive, and machinery industries. Most complex or assembled parts require internal features (IF) such as holes, channels, slots, or guides for locational and mating requirements. Therefore, it is critical to understand and compare the structural and mechanical properties of additively manufactured and conventionally machined IFs.

In this study, mechanical and microstructural properties of Inconel 718 (Inc718) alloy internal features, manufactured either as-built with AM or machining of additively manufactured (AMed) part thereafter were investigated.

The results showed that the average ultimate tensile strength (UTS) of additively manufactured center internal feature (AM-IF) is almost analogous to the machined internal feature (M-IF). However, the yield strength of M-IF is greater than that of AM-IF due the greater surface roughness of the internal feature in AM-IF, which is deemed to surpass the effect of microstructure on the mechanical performance. The results of digital image correlation (DIC) analysis suggest that AM-IF and M-IF conditions have similar strain values under the same stress levels but the specimens with as built IF have a more locally ductile region around their IF, which is confirmed by hardness test results. But this does not change global elongation behavior. The microstructural evolution starting from as-built (AB) and heat-treated (HT) samples to specimens with IF are examined. The microstructure of HT specimens has bimodal grain structure with d phase while the AB specimens display a very fine dendritic microstructure with the presence of carbides. Although they both have close values, machined specimens have a higher frequency of finer grains based on SEM images.

It was shown that the concurrent creation of the IF during AM can provide a final part with a preserved ultimate tensile strength and elongation but a decreased yield strength. The variation in UTS of AM-IF increases due to the surface roughness near the internal feature as compared to smooth internal surfaces in M-IF. Hence, the outcomes of this study are believed to be valuable for the industry in terms of determining the appropriate production strategy of parts with IF using AM and postprocessing processes.

This paper aims to answer report how mentors who onboard newcomers to a high-stress social work organization can learn about their onboarding practice by treating onboarding as a wicked problem that escapes definitive formulation and final solutions.

The authors follow an action research approach with three iterations of learning about onboarding with mentors in a Danish social work organization struggling with an employee turnover exceeding 30%.

The authors unfold the authors’ emerging sensitivity to wickedity over the iterations of learning about onboarding with the mentors. As the authors foreground the wickedity of the authors onboarding in the last iteration, three lessons learned could be derived: it warrants the mentors’ continuous inquiry; opens inquiry into the ambivalence of mentoring; and convenes responsibility for inquiry to a community of mentors.

This study of problematic onboarding to high-stress social work shows the value of fore-grounding wickedity instead of hiding it with a positive framing. This wickedity rests on situated grounding and is only transferrable to other organizations with the utmost caution.

High-stress social work organizations without the capacity to systematically sustain best practices for onboarding may, instead, increase attention to the wickedity of onboarding as a motivation for continuous inquiry by a broader community of mentors.

To the best of the authors’ knowledge, this paper is the first to present an action research study of problem wickedity to motivate mentors’ inquiry into onboarding newcomers to high-stress social work.

The Quality Assurance Agency (QAA) for Higher Education in the UK focuses on maintaining, enhancing and standardising the quality of higher education. Of significant impact are the development of subject benchmark statements (SBS) by the QAA, which describe the type and content of study along with the academic standards expected of graduates in specific disciplines. Prior to 2022, the QAA did not have a SBS to which higher education policing programmes could be directly aligned.

Over 12-months, a SBS advisory group with representatives from higher education across England, Scotland, Wales and Northern Ireland, The College of Policing, QAA, Police Federation of England and Wales and policing, worked in partnership to harness their collective professional experience and knowledge to create the first UK SBS for policing. Post publication of the SBS, permission was sought and granted from both the College of Policing and QAA for members of the advisory group to reflect in an article on their experiences of collaborating and working in partnership to achieve the SBS.

There is great importance of creating a shared vision and mutual trust, developed through open facilitated discussions, with representatives championing their cause and developing a collaborative and partnership approach to completing the SBS.

A collaborative and partnership approach is essential in developing and recognising the academic discipline of policing. This necessarily requires the joint development of initiatives, one of which is the coming together of higher education institutions, PSRBs and practitioner groups to collaborate and design QAA benchmark statements.

The SBS advisory group has further driven forward the emergence of policing as a recognised academic discipline to benefit multiple stakeholders.

The SBS for policing is the first across the UK. The authors experiences can be used to assist others in their developments of similar subject specific benchmarking or academic quality standards.

The stress concentration factor (SCF) is commonly utilized to assess the fatigue life of a tubular T-joint in offshore structures. Parametric equations derived from experimental testing and finite element analysis (FEA) are utilized to estimate the SCF efficiently. The mathematical equations provide the SCF at the crown and saddle of tubular T-joints for various load scenarios. Offshore structures are subjected to a wide range of stresses from all directions, and the hotspot stress might occur anywhere along the brace. It is critical to incorporate stress distribution since using the single-point SCF equation can lead to inaccurate hotspot stress and fatigue life estimates. As far as we know, there are no equations available to determine the SCF around the axis of the brace.

A mathematical model based on the training weights and biases of artificial neural networks (ANNs) is presented to predict SCF. 625 FEA simulations were conducted to obtain SCF data to train the ANN.

Using real data, this ANN was used to create mathematical formulas for determining the SCF. The equations can calculate the SCF with a percentage error of less than 6%.

Engineers in practice can use the equations to compute the hotspot stress precisely and rapidly, thereby minimizing risks linked to fatigue failure of offshore structures and assuring their longevity and reliability. Our research contributes to enhancing the safety and reliability of offshore structures by facilitating more precise assessments of stress distribution.

Precisely determining the SCF for the fatigue life of offshore structures reduces the potential hazards associated with fatigue failure, thereby guaranteeing their longevity and reliability. The present study offers a systematic approach for using FEA and ANN to calculate the stress distribution along the weld toe and the SCF in T-joints since ANNs are better at approximating complex phenomena than standard data fitting techniques. Once a database of parametric equations is available, it can be used to rapidly approximate the SCF, unlike experimentation, which is costly and FEA, which is time consuming.

This chapter shares the challenges that scholars experienced during the pandemic and their responses to them. We find that participants responded to complex work and home challenges through ethics of grit and perseverance. Offering a caution against grit mindsets, we argue that academics would benefit from opportunities to develop fuller forms of resilience. To do so, we recommend that higher education institutions co-construct locally and culturally relevant conceptualisations of resilience and enact trauma-informed practice to better support academic resilience in their faculties.

The purpose of this study is to investigate the thermoforming process of 3D-printed parts made from polylactic acid (PLA) and explore its application in producing wrist-hand orthoses. These orthoses were 3D printed flat, heated and molded to fit the patient’s hand. The advantages of such an approach include reduced production time and cost.

The study used both experimental and numerical methods to analyze the thermoforming process of PLA parts. Thermal and mechanical characteristics were determined at different temperatures and infill densities. An equivalent material model that considers infill within a print is proposed. Its practical use was proven using a coupled finite-element analysis model. The simulation strategy enabled a comparative analysis of the thermoforming behavior of orthoses with two designs by considering the combined impact of natural convection cooling and imposed structural loads.

The experimental results indicated that at 27°C and 35°C, the tensile specimens exhibited brittle failure irrespective of the infill density, whereas ductile behavior was observed at 45°C, 50°C and 55°C. The thermal conductivity of the material was found to be linearly related to the temperature of the specimen. Orthoses with circular open pockets required more time to complete the thermoforming process than those with hexagonal pockets. Hexagonal cutouts have a lower peak stress owing to the reduced reaction forces, resulting in a smoother thermoforming process.

This study contributes to the existing literature by specifically focusing on the thermoforming process of 3D-printed parts made from PLA. Experimental tests were conducted to gather thermal and mechanical data on specimens with two infill densities, and a finite-element model was developed to address the thermoforming process. These findings were applied to a comparative analysis of 3D-printed thermoformed wrist-hand orthoses that included open pockets with different designs, demonstrating the practical implications of this study’s outcomes.

In this article, the author discusses works from the French Documentation Movement in the 1940s and 1950s with regard to how it formulates bibliographic classification systems as documents. Significant writings by Suzanne Briet, Éric de Grolier and Robert Pagès are analyzed in the light of current document-theoretical concepts and discussions.

Conceptual analysis.

The French Documentation Movement provided a rich intellectual environment in the late 1940s and early 1950s, resulting in original works on documents and the ways these may be represented bibliographically. These works display a variety of approaches from object-oriented description to notational concept-synthesis, and definitions of classification systems as isomorph documents at the center of politically informed critique of modern society.

The article brings together historical and conceptual elements in the analysis which have not previously been combined in Library and Information Science literature. In the analysis, the article discusses significant contributions to classification and document theory that hitherto have eluded attention from the wider international Library and Information Science research community. Through this, the article contributes to the currently ongoing conceptual discussion on documents and documentality.