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The purpose of this study was to introduce three-dimensional printing (3DP) of functionally graded sandwich foams (FGSFs). This work was continued by predicting the mechanical buckling and free vibration behavior of 3DP FGSFs using experimental and numerical analyses.

Initially, hollow glass microballoon-reinforced high-density polyethylene-based polymer composite foams were developed, and these materials were extruded into their respective filaments. These filaments are used as feedstock materials in fused filament fabrication based 3DP for the development of FGSFs. Scanning electron microscopy analysis was performed on the freeze-dried samples to observe filler sustainability. Furthermore, the density, critical buckling load (P_cr), natural frequency (f_n) and damping factor of FGSFs were evaluated. The critical buckling load (P_cr) of the FGSFs was estimated using the double-tangent method and modified Budiansky criteria.

The density of FGSFs decreased with increasing filler percentage. The mechanical buckling load increased with the filler percentage. The natural frequency corresponding to the first mode of the FGSFs exhibited a decreasing trend with an increasing load in the pre-buckling regime and an increase in post-buckled zone, whereas the damping factor exhibited the opposite trend.

The current research work is valuable for the area of 3D printing by developing the functionally graded foam based sandwich beams. Furthermore, it intended to present the buckling behavior of 3D printed FGSFs, variation of frequency and damping factor corresponding to first three modes with increase in load.

Many factors contribute to public rail transit use in an urban network. However, a dysfunctional relationship between the built environment and the transport system significantly deters such use. Architects, urban designers, town planners and policymakers must understand the factors that promote or deter pedestrian use of the urban environment.

The paper investigates four connectivity and walkability factors for three different metro stations in Doha, Qatar: Al Aziziyah, Hamad Hospital and West Bay. The analysis includes pedestrian sheds, block sizes, ground-level land uses and connectedness in the urban spatial network based on catchment contour maps using space syntax.

The results indicate the three metro stations and neighborhoods are representative of diverse type of neighborhoods in Doha: relatively compact but expansive for the Hamad Hospital Station area, metrically and topologically restrictive due to the poor planning and the peninsular location of the reclaimed land in the West Bay area, and expansive, shallow and reliant on attraction for the Al Waab transportation corridor associated with Al Aziziyah Station.

Time factors and temporary closure/capacity reductions due to the global pandemic restricted planned efforts to collect more pedestrian use data based on passive observations and preference choices using surveys during the study. Nonetheless, adapting the investigation to the circumstances produced significant findings.

The analysis can help us develop better guidelines and diagnostic tools to calibrate design and planning strategies promoting more walkable, healthy and sustainable neighborhoods.

The study is original due to examining stations of the new Doha Metro for the first time. However, it relies on well-established representational techniques in urban morphology and space syntax research.

This paper aims to identify the current situation of higher education institutions in Spain regarding the introduction of the Sustainable Development Goals in the classroom, and what is the role of mathematics in this task.

A review is made of how the concept of sustainability has evolved in higher education, its gradual introduction in the University and the way in which this subject is approached in the field of mathematics.

The study concludes that higher education has a key role to play in designing strategies that lead to the global sustainability of the planet. This implies major changes in degree curricula, assessment, competences and teacher training. Cross-disciplinarity and interdisciplinarity between different subjects within the same degree is a strategy for students to analyse the Sustainable Development Goals using mathematical techniques.

The University as an institution must train socially responsible professionals who are aware of the importance of promoting a sustainable world. Changes should be made to introduce values in the classroom that promote and encourage sustainability. Training should be seen as a continuous process that leads to the preparation of professionals committed to society and nature and who develop strategies aimed at improving the planet through values.

Through practical activities, the Sustainable Development objectives can be analysed from several subjects of the same degree, emphasising the interdisciplinary and transversal nature that should be the central axis of higher education. Each subject can develop a strategy for change in favour of sustainability that will be reinforced and increased by working together on the proposed teaching practice. In this way, the contents of the different subjects are not isolated, but rather the student can see how there is an interrelationship between them and with real life.

The main purpose of this paper is to discuss the suitability of moral and ordre public clauses, and to advance the view that ethical reflection within patent systems is valuable.

This is a conceptual paper that draws upon the present situation in Europe to illuminate a discussion of the different views about the morality patents, with particular emphasis on criticism of authors who have espoused a narrow interpretation of moral clauses, such as that adopted by the European Patent Office.

This research found that the claim that patent systems are not appropriate places in which to evaluate moral matters and, therefore, they cannot inform us about morality is false. This is because inventors do not need to wait for authorizing legislation prior to making use of their technology. Hence, moral implications can be evaluated.

These ideas also lead to important theoretical consequences, especially regarding the debate on value-laden science and technology. However, further efforts are needed to address other patent regimes, such as the non-European.

It is shown how the bioethicist community can be incorporated into patent offices. The responsibilities of examiners and businesses in the process are also discussed.

There have been a limited number of studies that examine the value of ethical considerations within the patent system. This paper provides a thought-provoking discussion of moral clauses in Europe. The author also suggests new ways of incorporating ethical scrutiny into patent systems.

The purpose of this study is to explore Generation Z (Gen Z) consumers’ sustainable consumption behaviors at a university campus by examining various antecedent and moderating influencers of their sustainable consumption behaviors.

A quantitative research methodology is used in this study. A structured questionnaire was administered (n = 279) to young college students (Gen Z consumers in the context of this study) enrolled at a large state university in the USA. The structural equation model was used to test the hypothesized relationships in the conceptualized model.

Study findings show that social responsibility (feelings, engagement and expectations) and external incentives (material and social) positively influence Gen Z consumers’ sustainability interests, which in turn influences their sustainable consumption behaviors (actions). Collectivist cultural values did not appear to have any statistically significant effect on Gen Z consumers’ sustainable consumption interests. Moreover, learned helplessness, perceived barriers and the awareness of the consequences of sustainability consumption actions did not have any significant moderating effect on Gen Z consumers’ sustainable consumption behavior.

The questionnaire was only sent to students majoring in business degrees, which may limit the generalizability of this study to broader Gen Z consumer populations. Expanding this study to include non-business students may be valuable as a next step. Replicating this study in different cultural environments of international countries could enhance the relationships identified in this study.

Consumer social responsibility education along with material and social incentives will encourage Gen Z consumers’ participation in sustainable behaviors at college campuses.

This research provides valuable insights into understanding the importance of consumer social responsibility and external incentives in influencing Gen Z consumers’ sustainable consumption intentions and behaviors. Accordingly, consumer social responsibility education and incentive programs need to be developed to encourage the participation of Gen Z consumers in sustainable consumption.

The purpose of this paper is to address the need for new approaches in locating items that closely match user preference criteria due to the rise in data volume of knowledge bases resulting from Open Data initiatives. Specifically, the paper focuses on evaluating SPARQL qualitative preference queries over user preferences in SPARQL.

The paper outlines a novel approach for handling SPARQL preference queries by representing preferences through symbolic weights using the possibilistic logic (PL) framework. This approach allows for the management of symbolic weights without relying on numerical values, using a partial ordering system instead. The paper compares this approach with numerous other approaches, including those based on skylines, fuzzy sets and conditional preference networks.

The paper highlights the advantages of the proposed approach, which enables the representation of preference criteria through symbolic weights and qualitative considerations. This approach offers a more intuitive way to convey preferences and manage rankings.

The paper demonstrates the usefulness and originality of the proposed SPARQL language in the PL framework. The approach extends SPARQL by incorporating symbolic weights and qualitative preferences.

Resin-based friction materials are the most widely used key materials in industry for braking and transmission. However, the friction coefficient of resin-based friction materials significantly decreases at temperatures above 300°C, which reduces their friction performance.

This study combines elevated-temperature mechanical experiments with friction and wear experiments to explain the thermal degradation resistance performance and temperature recovery performance of resin-based friction materials. It also investigates the influence of friction material strength and worn morphology on the friction coefficient of materials at elevated temperature.

The experimental results show that the increase in friction coefficient of friction materials below 300°C is mainly due to the increase in worn morphology characterization parameters, and the thermal degradation phenomenon above 300°C is mainly due to the decrease of shear strength of friction film. Basalt fiber can significantly improve the thermal degradation resistance of friction materials. The friction coefficient of basalt fiber-reinforced specimens after thermal degradation reaches 0.421–0.443, which is 19–25% higher than the original. The thermal decay rate is 9.03–11.0%, which is 7.9–9.87% lower than the original. Moreover, the friction coefficient has good cooling recovery performance.

Revealed the thermal degradation mechanism of resin-based friction materials, verified that basalt fibers can improve the thermal degradation resistance of friction materials and provided reference for the development of new friction materials.

When improving business processes, process analysts can use data-driven methods, such as process mining, to identify improvement opportunities. However, despite being supported by data, process analysts decide which changes to implement. Analysts often use process visualisations to assess and determine which changes to pursue. This paper helps explore how process mining visualisations can aid process analysts in their work to identify, prioritise and communicate business process improvement opportunities.

The study follows the design science methodology to create and evaluate an artefact for visualising identified improvement opportunities (IRVIN).

A set of principles to facilitate the visualisation of process mining outputs for analysts to work with improvement opportunities was suggested. Particularly, insights into identifying, prioritising and communicating process improvement opportunities from visual representation are outlined.

Prior work focuses on visualisation from the perspectives – among others – of process exploration, process comparison and performance analysis. This study, however, considers process mining visualisation that aids in analysing process improvement opportunities.

The purpose of this study is to develop a transient wheel–rail rolling contact model to primarily investigate the rail damage under wet condition when the train passes through the welded joints.

The impact force induced by welded joints is obtained through vehicle–track coupling dynamics. The normal and tangential wheel–rail contact pressures were solved by elastohydrodynamic lubrication (EHL) theory and simplified third-body layer theory, respectively. Then, the obtained tangential pressure and normal pressure were applied to the finite element model as moving loads, simulating cyclic loading. Finally, the shakedown map and critical plane method were used to predict rolling contact fatigue (RCF) and the initiation of fatigue cracks.

The results indicate that RCF will occur and fatigue cracks are more prone to appear on the subsurface of the rail, specifically around 2.7 mm below the rail surface in the vicinity of the welded joint and its heat-affected zone.

The cosimulation of numerical model and finite element model was implemented. The influence of surface roughness and fluids was considered. In this model, the normal and tangential wheel–rail contact pressure, the stress and strain and the rail fatigue cracks were obtained under a rail-welded joint excitation.

In the last few years, the size of Linked Open Data (LOD) describing artworks, in general or domain-specific Knowledge Graphs (KGs), is gradually increasing. This provides (art-)historians and Cultural Heritage professionals with a wealth of information to explore. Specifically, structured data about iconographical and iconological (icon) aspects, i.e. information about the subjects, concepts and meanings of artworks, are extremely valuable for the state-of-the-art of computational tools, e.g. content recognition through computer vision. Nevertheless, a data quality evaluation for art domains, fundamental for data reuse, is still missing. The purpose of this study is filling this gap with an overview of art-historical data quality in current KGs with a focus on the icon aspects.

This study’s analyses are based on established KG evaluation methodologies, adapted to the domain by addressing requirements from art historians’ theories. The authors first select several KGs according to Semantic Web principles. Then, the authors evaluate (1) their structures’ suitability to describe icon information through quantitative and qualitative assessment and (2) their content, qualitatively assessed in terms of correctness and completeness.

This study’s results reveal several issues on the current expression of icon information in KGs. The content evaluation shows that these domain-specific statements are generally correct but often not complete. The incompleteness is confirmed by the structure evaluation, which highlights the unsuitability of the KG schemas to describe icon information with the required granularity.

The main contribution of this work is an overview of the actual landscape of the icon information expressed in LOD. Therefore, it is valuable to cultural institutions by providing them a first domain-specific data quality evaluation. Since this study’s results suggest that the selected domain information is underrepresented in Semantic Web datasets, the authors highlight the need for the creation and fostering of such information to provide a more thorough art-historical dimension to LOD.