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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.

In the current era of Industry 4.0, the manufacturing industries are striving toward mass production with mass customization by considering human–robot collaboration. This study aims to propose the reconfiguration of assembly systems by incorporating multiple humans with robots using a human–robot task allocation (HRTA) to enhance productivity.

A human–robot task scheduling approach has been developed by considering task suitability, resource availability and resource selection through multicriteria optimization using the Linear Regression with Optimal Point and Minimum Distance Calculation algorithm. Using line-balancing techniques, the approach estimates the optimum number of resources required for assembly tasks operating by minimum idle time.

The task allocation schedule for a case study involving a punching press was solved using human–robot collaboration, and the approach incorporated the optimum number of appropriate resources to handle different types of proportion of resources.

This proposed work integrates the task allocation by human–robot collaboration and decrease the idle time of resource by integrating optimum number of resources.

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.

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 aims to investigate the behavior of different types of stone columns, including the short and floating columns, as well as the ordinary and the geosynthetic encased stone columns (OSC and GESC). The effectiveness of the geosynthetic encasement and the impact of the installation using the lateral expansion method on the column performance is evaluated through a three-dimensional (3D) unit cell numerical analysis.

A full 3D numerical analysis is carried out using the explicit finite element code PLAXIS 3D to examine the installation influence on settlement reduction (ß), lateral displacement (U_x) and vertical displacement (U_z) relative to different values of lateral expansion of the column (0% to 15%).

The findings demonstrate the superior performance of GESC, particularly short columns outperforming floating counterparts. This enhanced performance is attributed to the combined effects of geosynthetic encasement and increased lateral expansion. Notably, these strategies contribute significantly to decreasing lateral displacement (U_x) at the column’s edge and reducing vertical displacement (U_z) under the rigid footing.

In contrast to previous studies that examined the installation effect of OSC contexts, this paper presents a comprehensive investigation into the effect of geosynthetic encasement and the installation effects using the lateral expansion method in very soft soil, using 3D numerical simulation. The study emphasizes the significance of the consideration of geosynthetic encasement and lateral expansion of the column during the design process to enhance column performance.

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.

This paper establishes a quality model for automation assembly of range hood impeller based on generalized grey relational degree, it improves the debugging efficiency of the newly developed assembly workstation.

First, spot check the trial production impellers and obtain three indexes that reflect the assembly quality of the impellers. Then, analyze the parameters that affect the assembly quality of the impeller using grey relational analysis (GRA), establish a model for the assembly quality of the range hood impeller based on the generalized grey relational degree and identify the main parameters. After that, analyze the transmission structure of automation assembly workstation, identify the reasons that affect parameters and propose improvement plans. Finally, a trial production is conducted on the automation assembly workstation after adopting the improved plan to verify the quality model of impeller automation assembly.

The research shows that compared to manual assembly, the automation assembly quality of the impeller using GRA model has been improved, shortening the debugging cycle of the newly developed assembly workstation.

The newly developed automation equipment will have some problems in the trial production stage, which often rely on the experience of engineers for debugging. In this paper, the automation assembly quality model of range hood impeller based on GRA is established, which can not only ensure the quality of finished impeller but also shorten the debugging cycle of the equipment. In addition, GRA can be widely used in the commissioning of other automation equipment.

This study has developed a set of impeller automation assembly workstation. The debugging method in the trial production stage is beneficial to shorten the trial production time and improve the economic benefits.

The main purpose of the paper is to offer a personal view on the development of documentation/information and documentation (IuD) in Germany, while pointing out the need to further investigate the specific features of its development paths. The methodology is based on critical review of the available literature sources in the German language.

The paper uses the method of critical review of published documents in journals (especially in Nachrichten für Dokumentation), books and reports of state and provincial administrations that are directly related to monitoring and/or encouraging the development of the young field of documentation.

The paper offers a review and interpretation of the most significant development phases, the contributions of individuals and the influence of the official state and information policy based on the consulted sources.

This research is limited to the literature written in German language.

The paper could be of interest to researchers and professionals who are interested in the development of documentation.

The paper covers the period after the World War II until the end of 1980s that is especially interesting from the social point of view in divided Germany.

To the author’s knowledge, there is no comprehensive history of documentation in German-speaking countries written in English. This paper is the result of a research project started three years ago with colleagues from Germany, Austria and Switzerland, that aims to cover all phases of the appearance and development of information science in German-speaking countries and could be understood as a kind of introduction to papers planned to follow.

The research focused on analysing a unique type of heat exchanger that uses swirling air flow over heated tubes. This heat exchanger includes a round baffle plate with holes and opposite-oriented trapezoidal air deflectors attached at different angles. The deflectors are spaced at various distances, and the tubes are arranged in a circular pattern while maintaining a constant heat flux.

This setup is housed inside a circular duct with airflow in the longitudinal direction. The study examined the impact of different inclination angles and pitch ratios on the performance of the heat exchanger within a specific range of Reynolds numbers.

The findings revealed that the angle of inclination significantly affected the flow velocity, with higher angles resulting in increased velocity. The heat transfer performance was best at lower inclination angles and pitch ratios. Flow resistance decreased with increasing angle of inclination and pitch ratio.

The average thermal enhancement factor decreased with higher inclination angles, with the maximum value observed as 0.94 at a pitch ratio of 1 at an angle of 30°.