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A 3D finite element (FE) model based on the double ellipsoidal heat source was developed to investigate the evolution of temperature and stress fields during the multilayer and multi-pass wire and arc additive manufacturing (WAAM) process. This paper aims to investigate the evolution of temperature and stress fields during the multilayer and multi-pass wire and arc additive manufacturing (WAAM) process by developing a 3D finite element (FE) model based on the double ellipsoidal heat source.

Experimental thermal cycle curves and residual stresses were obtained by thermocouples and X-ray diffraction, respectively. The validity of the model was verified by the corresponding experimental results.

The deposition process of the upper pass led to the partial remelting of the lower deposited pass. The thermal process of the current-deposited pass alleviated the stress concentration in the previous-formed passes. A more uniform temperature distribution could be obtained by using the reciprocating deposition path. Compared to the reciprocating deposition path, the peak values of the transverse and longitudinal tensile residual stresses of the deposited sample under the unidirectional deposition path were reduced by 15 MPa and increased by 13 MPa, respectively. The heat conduction in the deposited passes could be improved by extending the inter-pass cooling time appropriately. With an increase in the inter-pass cooling time, the longitudinal residual stress in the middle region of sample along longitudinal and transverse directions showed increase and decrease–increase trends, respectively, while the transverse residual stress exhibited decrease trend.

This study enhances the understanding of temperature and stress fields evolution during the multilayer and multi-pass cold metal transfer-WAAM processes of magnesium alloy and provides the reference for parameter optimization.

The overall aim of this study is to improve our understanding of the strength of attraction factors of professional football club brands with foreign fans, and of the influence of demographics and individual characteristics on the influence of these factors in the context of sport spectatorship services.

This research was based on a quantitative study surveying 1,160 Chinese fans of English Premier League clubs and its results were produced through exploratory and confirmatory factor analyses. They identify the relative importance of 21 organisation– (e.g. star players, charismatic managers, team kits, partnerships and alliances, etc.), market and environment– (e.g. peer influence, TV coverage, etc.), and experience– (e.g. personal bonds, past attendance, etc.) induced service brand attraction points that were categorised into six main factors: star players, on-the-field performance, brand identity, marketing and merchandising, localism and experience.

Organisation-induced factors are the most important club brand attraction factors for Chinese fans. ANOVA analysis showed that demographic (i.e. gender, age, and education) and individual (i.e. brand identification and loyalty levels) characteristics influence the importance of attraction factors for fans. For instance, fans who had previously supported a different club brand rated the marketing and merchandising dimensions lower, localism higher, on-the-field performance lower and brand identity lower than those who had always supported the same club.

These results emphasise the importance of segmentation when considering consumer attraction to professional sport brands. They also provide specific practical knowledge that is useful when expanding into new foreign markets.

This work aims to address source and dynamics of institutional change. It seeks to develop analytic tools by adaptation of Schumpeterian notion on entrepreneurship, Nelson's work on basic institutions and specific institutions, and Nonaka's middle‐up‐down framework of knowledge management in contrast to top‐down process. Pragmatically it attempts to understand how to improve policy capacity that challenges China seriously.

The work adopts a detailed case study method. A paired case is chosen with the criteria that they have widespread impact in China, and are representative of general and specific institutional change, respectively. Data came from mixed sources: field work and publications. Comparison of the paired cases identifies similarities and differences of different institutional change.

Similarities in the cases are in the important role of institutional entrepreneurs, crucial necessity of field experimentation, and regulatory and legislative means of knowledge processing. Differences are that centralized “top‐down” process of knowledge development, together with committed and centrally guided field experimentation, characterizes general institutional change. In contrast, coordinated and distributed “middle‐up‐down” process, together with autonomously emerged creation at the grassroots, characterizes specific institutional change.

This is a new research area. Many more empirical and theoretical works are needed.

As to how China should improve policy capacity, the study indicates: to focus policy learning on specific parts and facets of institutional settings; to change policy‐makers' role from omni‐competent controller to catalyst/promoter of institutional change; to assign an active role to middle levels and allow broader participation and diverse experimentations.

The author explores interesting details of institutional entrepreneurship and institutional changes based on the two case studies. This work fills the gap of how to analyze institutional change from the innovation/innovation systems perspective.

This paper aims to review the latest management developments across the globe and pinpoint practical implications from cutting-edge research and case studies.

This briefing is prepared by an independent writer who adds their own impartial comments and places the articles in context.

Identification of influential attraction points can help European soccer clubs to exploit soaring interest among football supporters in China. Such points can enable teams to differentiate themselves from rival brands and consider various demographic and individual factors in order to target different fan segments.

The briefing saves busy executives and researchers hours of reading time by selecting only the very best, most pertinent information and presenting it in a condensed and easy-to-digest format.

This study aims to develop a hierarchical reliability framework to evaluate the service delivery performance of education public–private partnerships (PPPs) effectively and efficiently during long-term operations.

The research design included development and test phases. In the development phase, three performance layers, i.e. indicator, component and system, in the education service delivery system were identified. Then, service component reliability was computed through first order reliability method (FORM). Finally, the reliability of the service system was obtained using dynamic component weightings. A PPP school example in Australia was set up in the test phase, where performance indicators were collected from relevant contract documents and performance data were simulated under three assumptive scenarios.

The example in the test phase yielded good results for the developed framework in evaluating uncertainties of service delivery performance for education PPPs. Potentially underperforming services from the component to the system level at dynamic timepoints were identified, and effective preventative maintenance strategies were developed.

This research enriches reliability theory and performance evaluation research on education PPPs. First, a series of performance evaluation indicators are constructed for assessing the performance of the service delivery of the education PPP operations. Then, a reliability-based framework for service components and system is developed to predict service performance of the PPP school operations with consideration of a range of uncertainties during project delivery.

The developed framework was illustrated with a real-world case study. It demonstrates that the developed reliability-based framework could potentially provide the practitioners of the public sector with a basis for developing effective preventative maintenance strategies with the aim of prolonging the service life of the PPP schools.

Evaluating education PPPs is challenging as it involves long-term measurement of various service components under uncertainty. The developed reliability-based framework is a valuable tool to ensure that reliability is maintained throughout the service life of education PPPs in the presence of uncertainty.

This study is a pilot study exploring the usefulness and ease of use of a prototype VR PetCPR system and discusses the possibility of using it to facilitate pet healthcare skills acquisition. The designed VR PetCPR training system aims to provide pet healthcare professionals with an inexpensive, accessible and reliable CPR training tool and refine their skills in a controlled and simulated environment.

The study was conducted in a one-day workshop. The workshop consisted of the morning section (Section A) and the afternoon section (Section B). Section A was the knowledge acquisition stage. Section B is the VR PetCPR stage. Trainees were then given 30 min to experience the VR PetCPR set. When trainees were ready, they were required to complete two trials of dog CPR practice. After the practice, trainees completed the questionnaire and reported their attitudes toward VR PetCPR practice.

Overall, trainees held positive attitudes toward the effectiveness and usefulness of the VR PetCPR. After practicing skills via VR CPR, over half of the trainees responded that the system is effective in helping them understand the essential knowledge (e.g. operation status, operation positions, etc.) of performing CPR skills on a 30-pound dog. A significantly positive attitude was reported on trainees’ perceptions toward the ease of use of practicing their chest compression skills with the PetCPR. The positive attitudes significantly outnumbered the negative attitudes on explicit instruction and guidance, accessibility, convenience in practice and straightforward interface.

From data collected from 16 animal hospitals in the United States, Europe and Australia with 709 cases, 147 dogs (28%) and 58 cats (30%) temporarily attained ROSC during CPR, and 14 dogs (3%) and four cats (2%) survived to hospital discharge. Training veterinary CPR techniques and implementing RECOVER guidelines still have a long way to go. However, recent virtual reality simulations for CPR training were mainly designed for human patients CPR (Issleib et al., 2021; Liu et al., 2022; Almousa et al., 2019; Wong et al., 2018). The VR PetCPR remains a missing puzzle in the current VR training designs.

This paper aims to study the influence of NaNO₂ on the chemical composition of passivation film.

X-ray photoelectron spectroscopy and X-ray diffraction were selected to determine the composition of passivation film of steel bars in mortar. The specimens were exposed to the chloride solution, carbonation environment and the coupling effects of chloride solution and carbonation. The chemical composition and micro structures at 0 and 5 nm from the outer surface of the passivation film of steel bars were analyzed.

Results showed that the nitrite inhibitor improved the forming rate of the passivation film and increased the mass ratio of Fe₃O₄ to FeOOH on the surface of steel bars. The component of Fe₃O₄ at 5 nm of the steel passivation film was more than that at 0 nm. Sodium ferrite in the pore solution was easily hydrolyzed and then FeOOH was formed. Therefore, due to the nitrite inhibitor, a “double layer structure” of the passivation film was formed to prevent steels bars from corrosion.

This is original work and may help the researchers further understand the mechanism of rust resistance by nitrite inhibitor.

The design and performance of X-band high power 3-bit phase shifter which has been fabricated in 0.25µm GaN HEMT technology are presented.

Each bit of this phase shifter design is based on high-pass/low-pass topology.

For all eight states, the insertion loss is 12.5 ± 2.5 dB from 8-10 GHz and the input return loss is better than 9 dB over 8-10 GHz. The 3-bit phase shifter achieves a RMS phase error of 1o at 8.5 GHz and a RMS amplitude error less than 1.1dB. The measured continuous wave power data demonstrates typical input RF power handing capability of 32 dBm at 8 GHz.

This is to the authors’ knowledge the first published results of 3-bit AlGaN/GaN phase shifter.

The purpose of this paper is to describe a novel method to compromise between planned (regulated) maintenance and outage initiation and unplanned (unregulated) maintenance and to find an economic model using which one can perform maintenance adequately and in the most optimal state.

In this paper, a system consisting of similar components is considered, and the role of each component in the system is explained. Then, the cost pertaining to failure in each asset is determined. Costs such as energy not supplied, penalties, human resources to resolve the defect and replacing assets are taken into account. Finally, a new comprehensive objective is proposed, and optimization is performed for a sample system.

In this paper, some graphs have been plotted from which plenty of information may be extracted. This is mentioned in the Conclusion.

In this paper, some graphs have been plotted from which plenty of information may be extracted. This is mentioned in the Conclusion.

The purpose of this paper is to compare corrosion behavior of a modified multilayer material with Cu before and after brazing process.

Sea water acidified accelerated tests (SWAATs), potentiodynamic polarization tests and scanning electron microscopy were used to study the corrosion behavior and macro/micro structures. Results indicate that the corrosion mechanisms of the sheets before and after brazing process are completely different.

The un-brazed material is uniform corrosion, while the brazed material has a high sensitivity to localized corrosion and loses cathodic protection to the core. It is found that brazing process causes copper transition from the core alloy into eutectic phases in the cladding, leading to higher E_corr and different potential distribution compared with those of un-brazed materials.

For the modified multilayer material after brazing, there are two stages of corrosion. First, corrosion attack takes place along eutectic phases in the cladding material, and then core alloy dissolves by forming a galvanic couple with the nobler residual cladding.