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Three-dimensional printing (3DP) is an established process to print structural parts of metals, ceramic and polymers. Further, multi-material 3DP has the potentials to be a milestone in rapid manufacturing (RM), customized design and structural applications. Being compatible as functionally graded materials in a single structural form, multi-material-based 3D printed parts can be applied in structural applications to get the benefit of modified properties.

The fused deposition modelling (FDM) is one of the established low cost 3DP techniques which can be used for printing functional/ non-functional prototypes in civil engineering applications.

The present study is focused on multi-material printing of primary recycled acrylonitrile butadiene styrene (ABS), polylactic acid (PLA) and high impact polystyrene (HIPS) in composite form. Thermal (glass transition temperature and heat capacity) and mechanical properties (break load, break strength, break elongation, percentage elongation at break and Young’s modulus) have been analysed to observe the behaviour of multi-material composites prepared by 3DP. This study also highlights the process parameters optimization of FDM supported with photomicrographs.

The present study is focused on multi-material printing of primary recycled ABS, PLA and HIPS in composite form.

Simulations exist for the prediction of the behaviour of building structural systems under fire, including two-way coupled fire-structure interaction. However, these simulations do not include detailed models of the connections, whereas these connections may impact the overall behaviour of the structure. Therefore, this paper proposes a two-scale method to include screw connections.

The two-scale method consists of (a) a global-scale model that models the overall structural system and (b) a small-scale model to describe a screw connection. Components in the global-scale model are connected by a spring element instead of a modelled screw, and the stiffness of this spring element is predicted by the small-scale model, updated at each load step. For computational efficiency, the small-scale model uses a proprietary technique to model the behaviour of the threads, verified by simulations that model the complete thread geometry, and validated by existing pull-out experiments. For four screw failure modes, load-deformation behaviour and failure predictions of the two-scale method are verified by a detailed system model. Additionally, the two-scale method is validated for a combined load case by existing experiments, and demonstrated for different temperatures. Finally, the two-scale method is illustrated as part of a two-way coupled fire-structure simulation.

It was shown that proprietary ”threaded connection interaction” can predict thread relevant failure modes, i.e. thread failure, shank tension failure, and pull-out. For bearing, shear, tension, and pull-out failure, load-deformation behaviour and failure predictions of the two-scale method correspond with the detailed system model and Eurocode predictions. Related to combined load cases, for a variety of experiments a good correlation has been found between experimental and simulation results, however, pull-out simulations were shown to be inconsistent.

More research is needed before the two-scale method can be used under all conditions. This relates to the failure criteria for pull-out, combined load cases, and temperature loads.

The two-scale method bridges the existing very detailed small-scale screw models with present global-scale structural models, that in the best case only use springs. It shows to be insightful, for it contains a functional separation of scales, revealing their relationships, and it is computationally efficient as it allows for distributed computing. Furthermore, local small-scale non-convergence (e.g. a screw failing) can be handled without convergence problems in the global-scale structural model.

Polyurethane (PUR) foam parts are traditionally manufactured using metallic molds, an unsuitable approach for prototyping purposes. Thus, rapid tooling of disposable molds using fused filament fabrication (FFF) with polylactic acid (PLA) and glycol-modified polyethylene terephthalate (PETG) is proposed as an economical, simpler and faster solution compared to traditional metallic molds or three-dimensional (3D) printing with other difficult-to-print thermoplastics, which are prone to shrinkage and delamination (acrylonitrile butadiene styrene, polypropilene-PP) or high-cost due to both material and printing equipment expenses (PEEK, polyamides or polycarbonate-PC). The purpose of this study has been to evaluate the ease of release of PUR foam on these materials in combination with release agents to facilitate the mulding/demoulding process.

PETG, PLA and hardenable polylactic acid (PLA 3D870) have been evaluated as mold materials in combination with aqueous and solvent-based release agents within a full design of experiments by three consecutive molding/demolding cycles.

PLA 3D870 has shown the best demoldability. A mold expressly designed to manufacture a foam cushion has been printed and the prototyping has been successfully achieved. The demolding of the part has been easier using a solvent-based release agent, meanwhile the quality has been better when using a water-based one.

The combination of PLA 3D870 and FFF, along with solvent-free water-based release agents, presents a compelling low-cost and eco-friendly alternative to traditional metallic molds and other 3D printing thermoplastics. This innovative approach serves as a viable option for rapid tooling in PUR foam molding.

The type 120 emergency valve is an essential braking component of railway freight trains, but corresponding diaphragms consisting of natural rubber (NR) and chloroprene rubber (CR) exhibit insufficient aging resistance and low-temperature resistance, respectively. In order to develop type 120 emergency valve rubber diaphragms with long-life and high-performance, low-temperatureresistant CR and NR were processed.

The physical properties of the low-temperature-resistant CR and NR were tested by low-temperature stretching, dynamic mechanical analysis, differential scanning calorimetry and thermogravimetric analysis. Single-valve and single-vehicle tests of type 120 emergency valves were carried out for emergency diaphragms consisting of NR and CR.

The low-temperature-resistant CR and NR exhibited excellent physical properties. The elasticity and low-temperature resistance of NR were superior to those of CR, whereas the mechanical properties of the two rubbers were similar in the temperature range of 0 °C–150 °C. The NR and CR emergency diaphragms met the requirements of the single-valve test. In the low-temperature single-vehicle test, only the low-temperature sensitivity test of the NR emergency diaphragm met the requirements.

The innovation of this study is that it provides valuable data and experience for future development of type 120 valve rubber diaphragms.

In response to coronavirus disease 2019, California State University Long Beach (CSULB) announced mandatory online course conversions on March 12, 2020. The College of Business designed a Student Online Learning Experience Survey to explore learners' experience, needs, expectations and challenges in the online learning environment.

The time-sensitive survey questions were administered using Qualtrics with Institutional Review Board approval. The authors used 5-point Likert scales to rate students' experience and satisfaction and performed statistical analysis. They assessed students' written comments to further corroborate statistical findings.

The results identify students' satisfaction are highly correlated to content coverage and interaction of online learning technologies. A combination of BeachBoard, Zoom, e-mails and publisher's website is valued most by the learners. Project-based experiential design is ranked #1 by graduate students. Noticeably, the upward trend of satisfaction with online modality from sophomore to senior is probably attributable to learners' maturity and number of years studied at CSU system. Overall, students generally dislike proctoring devices due to concerns of privacy, inequalities, mental stress, etc.

The evidence-based results offer innovative pedagogical recommendations for business education in higher education.

While prior studies examine student perceptions and satisfaction within the online education system, the study aims to deeply investigate the students' experience after a large-scale two-week institutional emergency course conversion mandate. This study systematically reviews students' experience with four aspects of online learning: (1) the adequacy of instructional designs; (2) the effectiveness of technology; (3) the appropriateness of the online learning material and (4) the integrity of online assessment and testing tools.

The purpose of this paper is to extend the understanding of Six Sigma (SS) and the underlying dimensions of its critical success factors (CSF) via an analysis of the effects of top management support (TMS), implementation strategy (IS), and collaborative team (CT) on project performance (PP) in Mexican manufacturing companies.

Based on a SS literature review, a survey was conducted to capture practitioners’ viewpoints about CSFs for SS implementation and their impact on performance in manufacturing companies. A factor analysis and structural equation modeling were conducted in order to identify and analyze causal relationships.

The results suggest that CSFs grouped in the constructs TMS, IS, and CT have a positive impact on PP as measured by cost reduction, variation reduction, and quality improvement.

Although the empirical data collected supported the proposed model, results might differ among organizations in different countries. In addition, the study did not analyze a unique performance metric; instead, general PP dimensions were used.

Boosting the TMS, IS, and CT enhances positive PP of SS in manufacturing companies.

IS as a construct has not been studied exhaustively; this work contributes to a better understanding of it and its impact on PP. Additionally, studies of SS in Latin America are limited, so this study gives a complementary vision to practitioners and researchers about it.

This paper aims to investigate the motivations of social entrepreneurs in East Africa to create a social enterprise and their identified links to successful social entrepreneurship in East Africa.

The authors employed a qualitative method by performing thematic analysis on a set of interviews on social entrepreneurs from East Africa who are Ashoka fellows.

The findings suggest that intense personal experiences linked to past-life events as well as a high achievement orientation towards improving livelihoods and creating impact serve as key triggers for social entrepreneurship. Successful entrepreneurship focusses on system change at national and local levels. Their success is also seen when the social entrepreneurs have achieved their mission and are no longer needed; thus, they become irrelevant. The paper discusses the implications of these findings on the model used for sustainable social entrepreneurship in East Africa.

Based on an exploratory research on Ashoka fellows, the study adds insight to their motivations and success which can be used in a wider scale study of the same.

The authors advance the scarce empirical research on East African social entrepreneurs, link success factors of social entrepreneurship to a recent framework on motivation to engage in social entrepreneurship and stimulate further research in the area. The study contributes to the literature on social entrepreneurship by linking success factors of social entrepreneurship to a recent framework on motivation to engage in social entrepreneurship.

The purpose of this study was to conduct a comprehensive analysis of the impact and its mechanism on the transfer of agricultural labor forces in the surrounding areas resulting from the establishment of a natural reserve, which holds great significance. The significance of this analysis is on the ecological protection of the natural reserve and the coordinated development of local social economy.

This study first performs an analysis on the impact and its mechanism on the establishment of the natural reserve on the transfer of agricultural labor forces from two aspects, which are push and pull factors. Then, based on county panel data in Jiangxi Province from 1995 to 2012, this study builds a generalized difference-in-difference model and performs an empirical study on the impact, heterogeneity and its mechanism on the establishment of the natural reserve on the transfer of agricultural labor forces.

The empirical analysis reveals that the establishment of natural reserves would significantly promote the transfer of agricultural labor forces to non-agricultural sectors. The robust test and placebo test with changed estimation methods verify the robust of the result. The result passes the parallel trend test and shows that the impact is most significant within one year after the implementation of the policy. From the mechanism analysis, the impact mainly comes from the “push” effect brought by the restricted development of agricultural production and primary industry on agricultural labor forces, and the “pull” effect brought by the development of local tertiary industry.

The conclusion of this study enriches the understanding of the internal mechanism between the establishment of natural reserves and the transfer of agricultural labor forces from the push and pull factors, and can provide reference for formulating policies to promote the coordinated development of natural reserve construction and regional social economy.

Due to high demand for international talents and skilful workforces, many countries around the world, especially the ageing populations are now looking for new ways and strategies to attract more international talent. Drawing on push-pull factor theory, integrated with theory of reasoned action (TRA), this research examines international students' intention to stay or to leave the host country after completion of the students' studies.

A conceptual model has been proposed and evaluated aimed at understanding the factors that influence the decision-making of international students studying in Finland. Data were collected from a sample of 292 international students in Finland and structural equation modelling (SEM) was used to analyse the data and examine the relationships between various constructs in the model.

The SEM results show that several factors influence students' decision to stay or leave the host country after graduation. Aspects related to host country, institutional and economic factors and social influence (norms) directly impact students' attitude towards staying. In addition, attitude towards staying not only has a direct impact on the intention to stay, but also mediates the relationship between different pulling factors and students' intention to stay in the host country. Moreover, challenges and barriers (such as local language, challenge of finding employment and challenge of assimilating into the community or making friends) have a negative impact on the decision to stay in the host country.

This study uses push-pull theory in the Finnish context, contributing to the growing body of literature on international education policies and practices. The findings highlight the need for a more holistic approach to supporting international students, one that considers the students' unique needs and experiences in the host country and provides the students with the necessary resources and support to succeed.

The study presents the push–pull motives and behavioural intentions of youth tourists and how these provide the foundation for the planning and development of Ghana’s tourism future. Since youth tourism (YT) is regarded as a niche market globally, the purpose of this paper is to identify the prospects of this form of tourism in a developing nation.

The study has utilised a convenience sampling approach in gathering data from 557 youth tourists, adapting existing instruments for measuring push–pull motives, satisfaction and behavioural intentions. The reliability and validity of the instruments were established through confirmatory factor analysis, exploratory factor analysis and Cronbach’s α analyses. Structural equation modelling is used to establish relationships.

The results revealed the positive effects of push and pull factors on tourists’ satisfaction as well as the significant influence of tourists’ satisfaction on youth behavioural intentions. However, push factors positively influenced pull factors of youth tourists.

The conclusion and recommendations of this study might not be congruent with the factors that motivate adults or student tourism, satisfaction and behavioural intentions.

The findings of the research validate the viability of YT activities and the behavioural intentions for future tourism market in Ghana. Ghana’s tourism sector should design interesting and competitive offers that attract youth tourists and address tourism growth.

To date, investigation into motives, satisfaction and behavioural intentions of youth tourists as the basis for future tourism development remains a virgin field in Ghana. This study has timely attempted to address this gap.