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The purpose of this paper is to propose a prediction method of gas-liquid two-phase flow patterns and reveal the flow characteristics in the suction chamber of a centrifugal pump.

A transparent model pump was experimentally studied, and the gas-liquid two-phase flow in the pump was numerically simulated based on the Eulerian–Eulerian heterogeneous flow model. The numerical simulation method was verified from three aspects: the flow pattern in the suction chamber, the gas spiral length and the external characteristics of the pump. The two-phase flow in the suction chamber was studied in detail by using the numerical simulation method.

There are up to eight flow patterns in the suction chamber. However, at a certain rotational speed, only six flow patterns are observed at the most. At some rotational speeds, only four flow patterns appear. The gas spiral length has little relationship with the gas flow rate. It decreases with the increase of the liquid flow rate and increases with the increase of the rotational speed. The spiral flow greatly increases the turbulence intensity in the suction chamber.

A method for predicting the flow pattern was proposed. Eight flow patterns in the suction chamber were identified. The mechanism of gas-liquid two-phase flow in the suction chamber was revealed. The research results have reference values for the stable operation of two-phase flow pumps and the optimization of suction chambers.

Concerning trends in graduate education, such as high attrition and underdeveloped skills, drive toward a new doctoral education approach. This paper aims to describe and propose a transformative doctoral education model (TDEM), incorporating elements that potentially address these challenges and expand the current practice. The model envisions discipline-specific knowledge coupled with a broader interdisciplinary perspective and addresses the transferable skills necessary to successfully navigate an ever-changing workforce and global landscape. The overarching goal of TDEM is to transform the doctoral student into a multi-dimensional and adaptive scholar, so the students of today can effectively and meaningfully solve the problems of tomorrow.

The foundation of TDEM is transformative learning theory, supporting the notion learner transformation occurs throughout the doctoral educational experience.

Current global doctoral education models and literature were reviewed. These findings informed the new TDEM.

Designed as a customizable framework for learner-centered doctoral education, TDEM promotes a mentor network on and off-campus, interdisciplinarity and agile career scope preparedness.

Within the TDEM framework, doctoral students develop valuable knowledge and transferable skills. These developments increase doctoral student career adaptability and preparedness, as well as enables graduates to appropriately respond to global and societal complex problems.

This proposed doctoral education framework was formulated through a review of the literature and experiences with curricular design and pedagogical practices at a research-intensive university’s teaching and learning center. TDEM answers the call to develop frameworks that address issues in doctoral education and present a flexible and more personalized training. TDEM encourages doctoral student transformation into adaptive, forward-thinking scholars and thriving in an ever-changing workforce.

Foundry produces cast metal components and parts for various industries and drives manufacturing excellence all over the world. Assuring quality of these components and parts is vital for the end product quality. The complexity in foundry operations increases with the complexity in designs, patterns and geometry and the quality parameters of the casting processes need to be monitored, evaluated and controlled to achieve expected quality levels.

The literature addresses quality improvement in foundry industry primarily focusing on surface roughness, mechanical properties, dimensional accuracy and defects in the cast parts and components which are often affected by numerous process variables. Primary data are collected from the experts working in sand and investment casting processes. The authors perform machine learning analysis of the data to model the quality parameters with appropriate process variables. Further, cluster analysis using k-means clustering method is performed to develop clusters of correlated process variables for sand and investment casting processes.

The authors identified primary process variables determining each quality parameter using machine learning approach. Quality parameters such as surface roughness, defects, mechanical properties and dimensional accuracy are represented by the identified sand-casting process variables accurately up to 83%, 83%, 100% and 83% and are represented by the identified investment-casting process variables accurately up to 100%, 67%, 67% and 100% respectively. Moreover, the prioritization of process variables in influencing the quality parameters is established which further helps the practitioners to monitor and control them within acceptable levels. Further the clusters of process variables help in analyzing their combined effect on quality parameters of casting products.

This study identified potential process variables and collected data from experts, researchers and practitioners on the effect of these on the quality aspects of cast products. While most of the previous studies focus on a very limited process variables for enhancing the quality characteristics of cast parts and components, this study represents each quality parameter as the function of influencing process variables which will enable the quality managers in Indian foundries to maintain capability and stability of casting processes. The models hence developed for both sand and investment casting for each quality parameter are validated with real life applications. Such studies are scarcely reported in the literature.

This study aims to solve the problem of temperature cross sensitivity of fiber Bragg grating in structural health monitoring, proposing a novel acceleration sensor based on strain chirp effect which is insensitive to temperature.

A kind of M-shaped double cantilever beam structure is developed. The fiber grating is pasted in the gradient strain region of the beam, and the chirp effect is produced under the action of non-uniform stress, and then the change of acceleration is converted into the change of reflection bandwidth to demodulate and eliminate the temperature interference. Through theoretical analysis, simulation and experimental verification with rectangular beam sensor.

The results show that the sinusoidal curvature beam sensor is insensitive to the change of temperature and is more likely to produce chirp effect. The sensitivity is about 317 pm/g, and the natural frequency is 56 Hz.

This paper fulfils an insensitive to temperature changes sensor which has effectively solved the temperature cross-sensitivity problem in building structure health monitoring.

Reducing construction waste generation and carbon emission in the construction industry is crucial for the “dual carbon” goal. Evaluating the efficiency of reducing construction waste generation and carbon emission in the construction industry at the regional level is an important evaluation basis for the sustainable development of the construction industry. It provides a basis for formulating construction waste and carbon reduction policies tailored to local conditions and comprehensively promote the sustainable development of the construction industry.

A three stage SBM-DEA model based on non-expected outputs is proposed by combining the SBM-DEA model with the SFA method. The proposed model is used to evaluate the efficiency of construction waste and carbon reduction in the construction industry in 30 regions of China from 2010 to 2020. Moreover, the study explores the impact of environmental variables such as urbanization level, proportion of construction industry employees, resident consumption level, and technological progress.

From 2010 to 2020, the efficiency of construction waste and carbon reduction in China’s construction industry has been increasing year by year. Provinces with higher efficiency of construction waste and carbon reduction in the construction industry are mainly concentrated in the eastern coastal areas, showing an overall pattern of “East>West>Northeast>Middle”. There is a clear correlation between the level of urbanization, the proportion of construction industry employees, residents’ consumption level, technological progress, labor input, machinery input, and capital investment. The construction waste and carbon emission efficiency of the construction industry in various provinces is greatly influenced by environmental factors.

The research results provide policy makers and business managers with effective policies for reducing construction waste generation and carbon emission in the construction industry, especially circular economy policies. To provide empirical support for further understanding the connotation of construction waste and carbon reduction in the construction industry, to create innovative models for construction waste and carbon reduction, and to promote the multiple benefits of construction waste and carbon reduction in the construction industry, and to provide empirical support for countries and enterprises with similar development backgrounds in China to formulate relevant policies and decision-making.

The construction industry is a high investment, high energy consumption, and high pollution industry. This study uses the three stage SBM-DEA model to explore the efficiency of construction waste and carbon reduction in the construction industry, providing a new perspective for the evaluation of sustainable development in the construction industry, enriching and improving the theory of sustainable development.

The rheology of solder paste significantly affects the qualities of stencil printing, tack and slump performance. This paper describes a series of tests performed on solder paste to investigate and determine the rheological properties of a group of solder pastes and fluxes, and the correlation of those properties with paste performance prior to reflow. Data indicate that: the incidence of print defects are proportional to the material’s compliant qualities (J1 and J2) and are inversely proportional to the elastic properties (G¢/G¢¢ and recovery) and meta‐rigidity (yield stress); slump resistance is proportional to elastic properties (recovery), solid characteristics (stress [G¢ = G¢¢]), and rigidity (|G*|); and that high elastic properties (recovery), low compliance (J1 and J2), and low solid characteristics (stress [G¢ = G¢¢]) are required in order to achieve high tack value. Good correlation between fluxes and solder pastes were observed for yield stress and recovery only, suggesting that those two properties are primarily dictated by fluxes.

The purpose of the paper is to investigate compensation and related welfare issues in the case of the expropriation of land for urban redevelopment in China.

A mixed methods quantitative and qualitative approach was selected to undertake the research. This involved a wide ranging qualitative review of the academic and policy literature to explore the relevant arguments and issues, combined with a quantitative regression analysis of survey data collected from research subjects.

The research identified the complex and changeable phenomena of urban village redevelopment in China, and the variable compensation arrangements used. The research found that monthly family income before land expropriation, monthly family expense before expropriation, the location of the housing expropriation and family unit size are important determinants for the property holders chosen methods of compensation. It also found that an increase in family size leads to a decreasing probability that the expropriated farmers choose the single monetary compensation relative to the alternative option of housing compensation. The degree of satisfaction with compensation, changes in monthly family income and expense are found to be significant determinants for changes in life satisfaction.

The research made the following four recommendations based upon the qualitative and quantitative analysis: that local governments should pay closer governance/ political attention to changes in the welfare of the farmers/ villagers whose property has been expropriated; that central and local government should aim to improve the compensation system for rural land and property expropriation, to make the compensation policy be perceived as fairer and more reasonable by citizens; that a broad National standard of compensation be used within a pragmatic locally focussed regime; that the Chinese Central, Provincial and Local governments can devise improved policy tools and make more effective policy interventions by learning from the experiences (both successes and failures) of other countries approaches to this topic. It also suggested that further research be undertaken investigating the multitude of local level policy experiments, as a way of developing better National compensation standards based upon those compensation standards that appear to be working – and have citizen support – at the local level.

The literature review identified recent developments in Chinese urban studies and originally synthesised both recent and longstanding work on the issue of urban villages in China. The research also suggested changes to the National and Local legal and policy framework for compensation cases in urban redevelopment expropriation scenarios.

This study aims to investigate Chinese young consumers’ brand loyalty toward sportswear products from a self-congruity perspective. With different performance observed between global and domestic sportswear brands in the Chinese market, this study also aims to examine the impact of country of origin on Chinese young consumers’ behavior toward sportswear brands.

A survey with street intercept method was conducted in Shanghai to collect data for this study. Multiple independent t-tests and structural equation modeling (SEM) with bootstrap method were used to test the hypotheses.

The SEM results indicate a significant influence of brand self-congruity on consumers’ brand association and perceived quality, which, in turn, influenced consumers’ brand loyalty. The multiple t-test results suggest a significant difference between Chinese and global sportswear brands in terms of consumers’ brand association and attitudinal brand loyalty. No significant difference was found in terms of consumers’ behavioral brand loyalty.

The main limitation of this study comes from the convenience student sample.

First, brands need to strategically design the brand image to represent the largest segment of the target market. Second, while global brands could focus on their pricing strategies, domestic brands need to focus more on maintaining a positive brand association in consumers’ mind.

This study contributes to the growing research on the self-congruity perspective of brand loyalty by empirically confirming the indirect effect of brand self-congruity on brand loyalty via the mediation effects of brand association and perceived quality in the context of the ever-growing Chinese sportswear market.

By using Technology Acceptance Model, the purpose of this study is to investigate how the perceived usefulness and ease-of-use of shopping mobile apps affects consumer’s flow experience, attitude, impulsive buying tendency (IBT) and urge to impulsive buying on halal fashion products.

A quantitative study was done on 357 Indonesian online shoppers to find out how perceived usefulness and ease of use of mobile shopping apps affect impulsive buying tendencies and urges on halal fashion products. Flow experience and attitude were used as mediating variables, and the research hypotheses were tested using Partial Least Square Structural Equation Modeling (PLS-SEM).

This study confirmed significant positive relationships between perceived usefulness and ease of use of mobile apps, flow experience, attitude, IBT and urge to impulsive buying. The results of this study show that perceived usefulness and ease of use influence flow experience. Ease of use also influences attitude, but perceived usefulness did not impact attitude. In addition, flow experience did not impact attitude. However, both flow experience and attitude influence IBT. Furthermore, IBT significantly mediated flow experience and attitude into urge to impulsive buying.

This study only captured consumers in one country, so its results cannot be generalized to other nations. Random sampling may limit result generalization. In this study, three mobile shopping applications were investigated and the results would have been different if more mobile shopping applications were investigated.

The study gives a better understanding of how the perceived usefulness and ease of use of mobile shopping apps affect a consumer's tendency and urge to impulsive buying on halal fashion products by using flow experience as mediating variable.