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This study explores the impact of parents’ and children’s early expectations on children’s later school persistence and completion of compulsory and secondary education, paying special attention to the parent-child agreement in early educational expectations. Results from analyzing longitudinal data from the Gansu Survey of Children and Families (GSCF) show that children often carry educational expectations quite different from their parents’. Consistent with previous research, children’s and their parents’ early expectations are strong predictors of children’s later educational attainment. More importantly, the analysis reveals that children benefit greatly when they share with their parents’ high expectations. Those children whose high expectations aligned with their parents fair best in later educational outcomes: They are more likely to complete compulsory education and secondary education. The combined determination of parents and children can help moderate the negative impact of poverty and facilitate children’s continued efforts in fulfilling their expectations. This positive impact holds even for children from the most impoverished families. This study points to the importance to recognize that there are non-material resources that family could provide to advance children’s education.

Increased interest in team dynamics has resulted in new methods for measuring teamwork over time. The primary purpose of this chapter is to provide a survey of recent developments in teamwork/collaboration measurement in an educational context. Key topics include conceptual frameworks, large-scale assessments, and innovative measurement techniques.

A range of methods for collecting and analyzing teamwork data are discussed, and five frameworks for measuring collaborative problem solving (CPS) over time are compared. Frameworks from Programme for International Student Assessment (PISA), Assessment and Teaching of 21st Century Skills (ATC21S) project, Educational Testing Service (ETS), ACT, and von Davier and Halpin (2013) are discussed. Results of assessments developed from these frameworks are also considered.

New techniques for measuring team dynamics over time have great potential to improve education and work outcomes. Preliminary results of the assessments developed from these frameworks show that important advances in teamwork measurement have been enabled by innovative task designs, data-mining techniques, and novel applications of stochastic models.

This novel overview and comparison of interdisciplinary approaches will help to indicate where progress has been made and what challenges are ahead.

The purpose of this paper is to investigate the density, surface quality, microstructure and mechanical properties of the components of the selective laser melting (SLM) parts made at different building orientations. SLM is an additive manufacturing technique for three-dimensional parts. The process parameters are known to affect the properties of the eventual part. In this study, process parameters were investigated in the building of 316L structures at a variety of building orientations and for which the fracture toughness was measured.

Hardness and tensile tests were carried out to evaluate the effect of consolidation on the mechanical performance of specimens. Optical and electron microscopy were used to characterise the microstructure of the SLM specimens and their effects on properties relating to fracture and the mechanics. It was found that the density of built samples is 96 per cent, and the hardness is similar in comparison to conventional material.

The highest fracture toughness value was found to be 176 MPa m^(1/2) in the oz. building direction, and the lowest value was 145 MPa m^(1/2) in the z building direction. This was due to pores and some cracks at the edge, which are slightly lower in comparison to a conventional product. The build direction does have an effect on the microstructure of parts, which subsequently has an effect upon their mechanical properties and surface quality. Dendritic grain structures were found in oz. samples due to the high temperature gradient, fast cooling rate and reduced porosity. The tensile properties of such parts were found to be better than those made from conventional material.

The relationship between the process parameters, microstructure, surface quality and toughness has not previously been reported.

The purpose of this study is to investigate the initial corrosion behavior of pure Mg, AZ31 and AZ91 alloys in phosphate buffer solution (PBS) and to characterize the features in corrosion type and resistance of the corrosion product layer.

The scanning electron microscopy, equipped with energy-dispersive spectroscopy, X-ray photoelectron spectroscopy and electrochemical impedance spectroscopy have been used to characterize the as-corroded samples. Besides, the Mg²⁺ concentration in PBSs has been determined by inductively coupled plasma atomic emission spectrum.

It has been found that pure Mg suffers pit corrosion, and AZ31 initially undergoes pit corrosion and then uniform corrosion dominates with an extended immersion duration. However, AZ91 exhibits the uniform corrosion with the highest corrosion rate among the three materials. Besides, the corrosion product layer on AZ31 has the best compactness and corrosion resistance.

The findings add depth in understanding the corrosion of pure Mg and its alloys in PBS and also have guiding significance in exploring the effects by alloyed elements to develop new biomaterials with better performance.

The purpose of this paper is to study new process parameters which were selected to achieve the full density of Ti-6Al-4V samples in different building orientations and investigate fracture toughness property and its relation to the microstructure, an area which has not previously been reported in full detail and which may offer information to a designer. Direct metal laser sintering (DMLS) is an additive manufacturing technique that directly manufactures three-dimensional parts, layer-by-layer, to scan and melt metal powders for aerospace applications.

Hardness and tensile tests were carried out to evaluate the effect of consolidation on the mechanical performance of specimens made at three different building directions. Optical and electron microscopy were used to characterise the microstructure of the DMLS specimens and their effects on the fractures and mechanical properties.

It was found that the built samples have an excellent density at 4.5 g/cm, and the sample surfaces parallel to the building direction are rougher than the perpendicular surfaces. The fracture toughness result was higher than that of the cast material for the same alloy and higher than the Ti-6Al-4V parts fabricated by electron beam melting. This results in the superior mechanical properties of DMLS, while slightly lower in the zy direction owing to cracks, porosity and surface finish.

The tensile strength was found to be higher than the wrought material, and the samples exhibited brittle fractures owing to the martensitic phase, which is caused by a high temperature gradient, and the mechanical properties change with the change in the microstructures at different building directions.

This paper contains original research.

The construction industry is a key driver of economic growth. However, the adverse impacts of construction and demolition waste (CDW) resulted from the active construction projects on the economy, environment, public health and social life necessitates an appropriate control and management of this waste stream. Developing and promoting the construction and demolition waste management (CDWM) hierarchy program at the strategic level is essential.

This study aims to propose a hybrid decision model that hybridizes the Integrated Determination of Objective Criteria Weights (IDOCRIW) and weighted aggregated sum product assessment (WASPAS) under a fuzzy environment.

The proposed method ranks the potential strategic alternatives by the sustainable development criteria to improve the performance of CDWM. As indicated in the results, the fuzzy approach in the decision-making process enables the transformation of linguistic variables into fuzzy numbers that show uncertainty and ambiguity in real-world systems. Moreover, the close correlation between the final ranking of the proposed methodology and the average priority order of the strategic alternatives obtained by five different multi-criteria decision-making (MCDM) methods implies the validity of the model performance.

This proposed model is an appropriate tool to effectively decide on the development of CDWM from a strategic point of view. It aims to establish an MCDM framework for the evaluation of effective strategies for CDWM according to the indices of sustainable development. Implementing proper operational plans and conducting research in CDWM has the highest priority, and enacting new and more stringent laws, rules and regulations against the production of CDW has secondary priority. This study contributes to the field by optimizing the CDWM by applying the top-priority strategies resulted from the proposed fuzzy hybrid MCDM methodology by the decision-makers or policy-makers to reach the best managerial strategic plan.

In the proposed methodology, the IDOCRIW technique is utilized and updated with the triangular fuzzy numbers for the first time in the literature to derive the weights of sustainable development criteria. The fuzzy WASPAS method is utilized for evaluation and providing a final ranking of the strategic alternatives.

The purpose of this paper is to investigate the effects of creator credibility and backer endorsement on the levels of donation to crowdfunding campaigns in a focal muslim community and to determine the success factors of projects in developing and developed countries.

This research adopts a quantitative approach, utilizing 223 crowdfunding projects from LaunchGood to examine the expected connections. The crowdfunding projects in the distinctive data set (Ramadan) are similar, permitting exploration of the role of creator credibility and backer endorsement in a unique context of religious-based crowdfunding activity.

Creators’ credibility and backers’ endorsements are decisive factors in crowdfunding success. Results from an additional test related to location (developing and developed countries) suggest that creators’ credibility is more important than backers’ endorsements, especially in developing countries.

The projects used in the data set are homogenous and take place in a specific context. The limited number of available observations influences the testing function and capacity of the models and variables. Further, the investigation is related to a specific community, so might not be applicable to all communities.

Potential supporters from the community are vital for the success of crowdfunding projects. This study informs campaign efforts in a religious community by stressing the importance of creators’ credibility and backers’ endorsements. The study also sheds light on factors that affect crowdfunding success in developing and developed countries.

This study helps to explain successful crowdfunding practices in donation-based crowdfunding projects within a religious community context. Results improve scholars’ ability to comprehend individuals’ supporting behavior, providing empirical evidence of creators’ credibility and backers’ endorsement on project success. The study also addresses the determinants of crowdfunding success in developing and developed countries.

The purpose of this paper is to analyze the influence of different parameters on the characteristics of the superconducting electrodynamic suspension (EDS) system.

The authors used an analytical model based on the dynamic circuit theory to perform the analysis. The authors proposed an inductance criterion to improve the calculation accuracy. They also proposed a three-dimension finite element method (FEM) to verify the validity of the analytical model.

The levitation force and guiding force increase with the superconducting magnet (SCM) speed and show a saturated trend, while the drag force decreases with the SCM speed. The vibration characteristic is the inherent characteristic of the superconducting EDS. The frequency and amplitude are affected by the gap between adjacent null-flux coils. The levitation force first increases and subsequently decreases with the levitation height. The total levitation force of the SCM increases with the superconducting coil (SC) number, while the average levitation force of an SC decreases with the SC number. The total levitation force nonlinearly increases with the SC number.

The authors introduced an inductance criterion for better understanding and using the analytical model, and they also proposed a 3D FEM method. The 3D FEM method could be extended to simulate the other EDS systems with more complex structures which the numerical model is no longer applicable. The results of the parameter study could deepen people’s understanding of EDS.

The aim of this paper is to develop a model based on system dynamics (SD) approach, which integrates three subsystems for simulating construction and demolition (C&D) waste management in Shenzhen, Mainland China.

SD approach was first used to construct the model for C&D waste management in Shenzhen. The model was then converted for running on computer through the software package “iThink”, which was specifically designed for SD modeling. The data required for model simulation was derived through various ways, including literature review, examination of official reports and yearbooks, and questionnaires. After all the parameters in the model were determined, simulation was carried out.

The model proposed in this research can provide an experimental simulation platform to investigate the complexity and interdependencies of factors in managing C&D waste in Shenzhen, Mainland China. The simulation results show that the pressing situation of C&D waste management in Shenzhen would aggravate if no effective measures were taken to address it during the simulation period. Participants' active participation and cost consideration are the two major factors affecting C&D waste reduction. Furthermore, new landfills should be planned to properly handle the C&D waste accumulated in Shenzhen over the past few years.

Although some studies have been conducted under the topic of C&D waste management during the past few years in Shenzhen – how to effectively and efficiently handle the waste is still unsolved. Factors affecting the effectiveness of C&D waste management have separately been examined in the previous studies, without considering their interrelations. The SD‐based model is developed in this research to investigate the complex and interdependent relationships among these factors. The model can deepen participants' understandings about C&D waste management and help explore the major factors affecting the effectiveness of management activities. The measures, which are proposed based on the simulation results, can serve as a valuable reference for planning C&D waste management in Shenzhen.

As construction and demolition(C&D) waste is one of the main solid waste generators in Hong Kong, its impact on the environment has become an imperative issue to the involved stakeholders. Although, C&D waste management has been receiving increasing attention from stakeholders and researchers since the early 1980s, how to manage C&D waste efficiently and effectively is, however, still in its early stages. Past research on C&D waste management has mainly focused on the separate aspects of waste management including waste reduction, reuse, recycle and response. A new approach is made in this paper to improve C&D waste management.

A simulation model is developed based on system dynamics methodology for strategic planning of C&D waste in Hong Kong by incorporating the relationship of major activities inherently involved in C&D waste management.

Finds that such an integrated simulation model will have the potential to assist decision makers and practitioners to better understand the complexity of information and processes involved in managing C&D waste throughout a project's life‐cycle.

This has shown that management of C&D waste can be facilitated by means of system dynamics to provide a better understanding of the dynamic interactions and interdependencies of the key areas of the C&D waste management process.