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This paper presents the approximate limit pressure solution for shape-imperfect and through-wall circumferential cracked (TWCC) 90° pipe bends at the intrados region. Finite element (FE) limit analysis was used to estimate the limit pressure by considering the small geometrical change effects.

Three-dimensional (3D) geometric linear FE methodology was implemented to investigate the limit pressure of structurally deformed TWCC 90° pipe bends. The material considered in the analysis is elastic perfectly plastic (EPP). The limit pressure of TWCC shape-distorted pipe bends was predicted from the corresponding internal pressure when von-Mises stress was equal to or just exceeded the material’s yield strength for all the models. The theoretical solution which was published in the literature was used to evaluate the current FE approach.

Ovality C_o and TWCC at the intrados region caused a considerable impact on pipe bends, while the thinning? C_t produced a negligible effect and hence was not included in the analysis. With the combined effect, the bend portion of pipe bend experiences substantial influence, and the TWCC effect consequently increases with 45^o, 60^o and 90^o crack angles and decreases the limit pressure of pipe bends. An improved closed-form empirical limit pressure solution was proposed for TWCC shape-distorted pipe bends at the intrados region.

In the limit pressure analysis of 90° pipe bends, the implications of structural irregularities (ovality and thinning) and TWCC have not been examined and reported.

One of the primary challenges associated with excavation near buildings is the significant decrease in the bearing capacity of nearby foundations during the initial stages before the stabilization of the excavation wall. This study aims to investigate the correlation between excavation height and foundation-bearing capacity under actual field conditions.

This paper uses a three-dimensional rotational failure mechanism to propose a novel method for estimating foundation-bearing capacity using the upper bound limit analysis approach.

The study delineates two distinct zones in the excavation height versus bearing capacity diagram. Initially, there is a significant reduction in foundation-bearing capacity at the onset of excavation, with decreases of up to 80% compared to its undisturbed state. Within a specific range of excavation heights, the bearing capacity remains relatively constant until reaching a critical height. Beyond this threshold, the entire soil mass behind the excavation wall becomes unstable. The critical excavation height is notably influenced by the soil's internal friction angle, excavation slope angle and soil cohesion parameter. Notably, when the ratio of excavation height to foundation width is less than 0.4, changes in slope angle have no significant impact on bearing capacity.

The bearing capacity estimates derived from the method proposed in this paper are deemed to reflect real-world scenarios closely compared to existing methodologies.

Heterogeneous and micro-structured materials have been the object of multiscale and homogenization techniques aimed at recognizing the elastic properties of the equivalent continuum. The proposed investigation deals with the mechanical characterization of the heterogeneous material structured metamaterials through analyzing the ultimate strength using the limit analysis of the Representative Volume Element (RVE). To get the desired material strength, a novel finite element formulation based on the derivation of self-equilibrated solutions through the finite elements devoted to calculating the lower bound theorem has been implemented together with the limit analysis in Melàn’s formulation.

The finite element formulation is based on discrete mapping of Volterra dislocations in the structure using isoparametric representation. Using standard finite element techniques, the linear operator V, which relates the self-equilibrated internal solicitation to displacement-like nodal parameters, has been built through finite element discretization of displacement and strain.

The proposed work presented an elastic homogenization of the mechanical properties of an elementary cell with a geometry known in the literature, the isotropic truss. The matrix of elastic constants was calculated by subjecting the RVE to numerical load tests, simulated with a commercial FEM calculation code. This step showed the dependence of the isotropy properties, verified with Zener theory, on the density of the RVE. The isotropy condition of the material is only achieved for certain section ratios between body-centered cubic (BCC) and face-centered cubic (FCC), neglecting flexural effects at the nodes. The density that satisfies Zener’s conditions represents the isotropic geomatics of the isotropic truss.

For the isotropic case, the VFEM procedure was used to evaluate the isotropy of the limit domain and was compared with the Mises–Schleicher limit domain. The evaluation of residual ductility and dissipation energy allowed a measurement parameter for the limit anisotropy to be defined. The novelty of the proposal consisted in the formulation of both the linearized and the nonlinear limit locus of the material; hence, it furnished the starting point for further limit analysis of the structures whose elementary volume has been described through the proposed approach.

This paper aims to explore the impact of COVID-19 on office space in Johannesburg. This study further explores the role of changing work practices in the office sector in South Africa because of the pandemic and its impact on future office space use planning and management.

To understand the footprints that the COVID-19 pandemic has left on the office space market in Johannesburg, this study uses semi-structured interviews, which were administered to corporate office users, and a thematic analysis was adopted to understand the views, perspectives and expectations of office users.

The study showed that space users perceive COVID-19-induced remote working as having benefits, opportunities and challenges. A notable shift in office space utilization has emerged, with employees increasingly opting for roles that permit remote work. This newfound flexibility, accommodating both on-site and remote work, often makes working from home more appealing than traditional office environments that may no longer align with users’ preferences for office spaces.

The study is limited to Johannesburg, South Africa, and may not apply to other African markets. Ten in-depth interviews were conducted, and analysis and results were deduced; this may be considered a limitation of this study.

The pandemic’s impact has brought about irreversible changes, compelling policymakers and business leaders to strategize and prepare. This proactive stance aims to prevent avoidable challenges for employees and companies during future pandemics. A thoughtful approach to the post-pandemic world can usher positive changes in the office and property sector. This includes the coexistence of both remote work and on-site working models.

This paper provides valuable insight into some of the outcomes of the COVID-19 pandemic in South Africa that are essential for future office space use planning and management. The insights from this study extend the literature and provide novel knowledge based on an office sector in the “global south.”

From a supply chain perspective, logistics firms collaborate with other supply chain members to extend their business scope. Investment in circular economy projects in the supply chain can not only broaden the scope of business but also increase the value of the entire supply chain. Third-party logistics companies are gradually participating in the construction and operation of many circular economy projects. How to coordinate multiple circular economy supply chain projects is at the core of its operation.

This paper first analyzes some typical supply chain projects in China and summarizes the main features of these projects. Secondly, considering the benefits of the project and the stakes of each project, a multi-stage stochastic programming model is established. Finally, Cplex, nested decomposition, LocalSolver and other methods are adopted to simulate and analyze the model.

The final experimental results find that the importance of coordinating multiple circular economy supply chain projects to increase the value of the entire supply chain. The multi-stage stochastic programming model presented in this research can provide a useful tool for logistics enterprises and third-party logistics companies to optimize their investment decisions and maximize their profits in the context of a circular economy.

There are still some limitations to this study; for example, it is limited to the analysis of circular economy supply chain projects in China. The study focused on third-party logistics companies, and other enterprises in the circular economy supply chain were not considered. The research also assumed that the benefits of each circular economy project and the stakes of each project were known, which may not always be the case in real-world scenarios.

This manuscript found that investing in other circular economy projects in the supply chain can broaden the scope of business and increase the value of the entire supply chain. Third-party logistics companies are gradually participating in the construction and operation of many circular economy projects, such as recycling and repurposing initiatives. It highlights the importance of coordinating multiple circular economy supply chain projects to increase the value of the entire supply chain. The multi-stage stochastic programming model presented in this research can provide a useful tool for logistics enterprises and third-party logistics companies to optimize their investment decisions and maximize their profits in the context of a circular economy.

Against the background of the popularity of social media and heritage tourism, this study aims to focus on world heritage sites, proposing a method to examine and compare the digital spatial footprints left by tourists using geographic information systems.

By analyzing user-generated content from social media, this research explores how digital data shapes the destination image of WHS and the spatial relationships between the components of this destination image. Drawing on the cognitive-affective model (CAM), it investigates through an analysis of integrated data with more than 20,000 reviews and 2,000 photos.

The creativity of this research lies in the creation of a comprehensive method that combines text and image analytics with machine learning and GIS to examine spatial relationships within the CAM framework in a visual manner.

The results reveal tourists' perceptions, emotions, and attitudes towards George Town and Malacca in Malaysia, highlighting several key cognitive impressions, such as history, museums, churches, sea, and food, as well as the primary emotions expressed. Their distributions and relationships are also illustrated on maps.

Tourism practitioners, government officials, and residents can gain valuable insights from this study. The proposed methodology provides a valuable reference for future tourism studies and help to achieve a sustainable competitive advantage for other heritage destinations.

This study addresses the gap in understanding text analytics within the service domain, focusing on new service development to provide insights into key research themes and trends in text analytics approaches to service development. It explores the benefits and challenges of implementing these approaches and identifies potential research opportunities for future service development. Importantly, this study offers insights to assist service providers to make data-driven decisions for developing new services and optimising existing ones.

This research introduces the hybrid thematic analysis with a systematic literature review (SLR-TA). It delves into the various aspects of text analytics in service development by analysing 124 research papers published from 2012 to 2023. This approach not only identifies key practical applications but also evaluates the benefits and difficulties of applying text analytics in this domain, thereby ensuring the reliability and validity of the findings.

The study highlights an increasing focus on text analytics within the service industry over the examined period. Using the SLR-TA approach, it identifies eight themes in previous studies and finds that “Service Quality” had the most research interest, comprising 42% of studies, while there was less emphasis on designing new services. The study categorises research into four types: Case, Concept, Tools and Implementation, with case studies comprising 68% of the total.

This study is groundbreaking in conducting a thorough and systematic analysis of a broad collection of articles. It provides a comprehensive view of text analytics approaches in the service sector, particularly in developing new services and service innovation. This study lays out distinct guidelines for future research and offers valuable insights to foster research recommendations.

This study aimed to analyze the free vibration of a radially graded Ni-Al2O3-based functionally graded (FG) disk with uniform thickness.

Using the energy method, natural frequencies of rotating and non-rotating disks were determined at the limit elastic angular speed. Material properties were estimated using a modified rule of mixture. Both even and uneven porosity variation effects were considered in the material modeling. Finite element analysis validated the analytical approach.

The study explored limit angular speeds and natural frequencies across various grading indices, investigating the impact of porosity types and grading indices on these parameters.

Insights from this research are valuable for researchers and design engineers involved in modeling and fabricating porous FG disks, aiding in more effective design and manufacturing processes.

This study contributes to the field by providing a comprehensive analysis of free vibration behavior in radially graded Ni-Al2O3-based FG disks. The incorporation of material modeling considering both even and uneven porosity variation adds originality to the research. Additionally, the validation through finite element analysis enhances the credibility of the findings.

Empirical literature is the primary source of understanding how policing can effectively reduce criminal activities. Spatial analyses can identify particular effects that can explain and assist in constructing appropriate regional strategies and policies; nevertheless, studies that use spatial regression methods are more limited and can provide a perspective on specific effects in a more disaggregated regional context.

This research aims to conduct a systematic literature review (SLR) to understand the relationship between crime indicators and police production using spatial regression models. We consider a combination of Kitchenham and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocols as a methodological strategy in five bibliographic databases for collecting scientific articles.

The SLR suggests a limited amount of evidence that meets the criteria defined in the research strategy. Several particularities are observed regarding police and criminal production metrics, either in terms of aggregation level, indicator transformations or scope of analysis. A broader time perspective did not necessarily indicate statistical significance compared to models with a single-period sample.

The findings suggest the possibility of expanding efforts by the public sector to provide policing data with the intention of conducting appropriate research using spatial analysis. This step could allow for a more robust integration between the public sector and researchers, strengthening policing strategies, evaluating the effectiveness of public security policies and assisting in the development of strategies for future policy actions.

Limited empirical evidence meets the criteria of spatial regression models with temporal components considering police production and criminality indicators. Constructing an SLR with this scope is an unprecedented contribution to the literature. The discussion can enhance the understanding of approaches for studying the relationship between police efforts and crime prevention.

Improving construction projects' performance through innovative approaches such as lean construction (LC) and offsite construction (OSC) methods are at the centre of various debates. However, there is a limited understanding of the current link between LC and OSC approaches. This study aims to conduct a scientometric analysis on LC and OSC research to unpack and establish the nexus and suggest future research focus.

Scientometric analysis was used to systematically examine existing literature on LC and OSC to identify possible connections. Relevant publications were extracted from the Scopus database, using inclusion and exclusion criteria. VOSviewer software was used as a visualisation technique to analyse and map the interrelations and connections of the concepts being studied. Bibliograhic data on the 68 selected papers were extracted from the Scopus database.

The search results cover the period between 2003 and 2021. Descriptive statistics show that the number of published papers has increased yearly. Researchers in the USA and Canada are the most productive authors regarding the number of published papers. The directions for future research suggested are the need to identify best practices for integrating LC and OSC methods, the need for more interdisciplinary and cross-country collaboration among researchers, the use of alternative research methods will provide a better understanding of the benefit of integrating LC and OSC techniques and more research is needed to showcase how the use of lean and offsite construction can facilitate the attainment of net-zero in the construction industry.

This study provides insights into the trends and gaps in knowledge on integrating LC and OSC methods and offers valuable insights to scholars and practitioners in integrating LC and OSC principles. This knowledge is vital for identifying strategies to improve the outcome of construction projects and contribute to the sustainable socio-economic development of cities across the globe.