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Recycled waste glasses have been widely used in Portland cement and concrete as aggregate or supplementary cementitious material. Compressive strength is one of the most important properties of concrete containing waste glasses, providing information about the loading capacity, pozzolanic reaction and porosity of the mixture. This study aims to propose highly nonlinear models to predict the compressive strength of concrete containing finely ground glass particles.

A robust machine leaning method called genetic programming is used the build the compressive strength prediction models. The models are developed using a number of test results on 50-mm mortar cubes containing glass powder according to ASTM C109. Parametric and sensitivity analyses are conducted to evaluate the effect of the predictor variables on the compressive strength. Furthermore, a comparative study is performed to benchmark the proposed models against classical regression models.

The derived design equations accurately characterize the compressive strength of concrete with ground glass fillers and remarkably outperform the regression models. A key feature of the proposed models as compared to the previous studies is that they include the simultaneous effect of various parameters such as glass compositions, size distributions, curing age and isothermal temperatures. Parametric and sensitivity analyses indicate that compressive strength is very sensitive to the curing age, curing temperature and particle surface area.

This study presents accurate machine learning models for the prediction of one of the most important mechanical properties of cementitious mixtures modified by waste glass, i.e. compressive strength. In addition, it provides an insight into the effect of several parameters influencing the compressive strength. From a computing perspective, a robust machine learning technique that overcomes the shortcomings of existing soft computing methods is introduced.

As for vibrating screen, the separation of granular materials is a very complicated process, particularly the screening with a swing trace. To study the characteristics of stratification and penetration in the swing vibrating screen, a three-dimensional numerical model was developed to simulate the screening process.

The discrete element method (DEM) was used to perform the numerical simulation, and the kinetic model of the swing screening was established. The regions of stratification and penetration were defined, and the mathematical functions relating fine particle ratio of stratification and penetration to time were presented using the least squares method.

The results show that the low value of frequency (5 and 10 Hz) has a limited effect on the stratification, while the obvious effect can be found at high frequency. A low frequencies or small swing angles may enhance the particle penetration. By studying the vibration parameters affecting the stratification and penetration rate, it is found that the frequency has more influence than the swing angle.

The higher screening efficiency and processing capacity can be further obtained for the swing vibrating screen by comparing with the linear vibrating screen. These results reveal the fundamental characteristics of particle motion in the swing screening, which will provide reliable guidance for studying the design optimization of vibrating screen.

The purpose of this paper is to propose a DC-port voltage balance strategy realizing it by logic combination modulation (LCM). This voltage balance strategy is brief and high efficient, which can be used in many power electronic devices adopting the cascaded H-bridge rectifier (CHBR) such as power electronic transformer (PET).

The CHBR is typically as a core component in the power electronic devices to implement the voltage or current conversion. The modulation method presented here is aiming to solve the voltage imbalance problem occurred in the CHBR with more stable work station and higher reliability in ordinary operating conditions. In particular, by changing the switch states smoothly and quickly, the DC-port voltage can be controlled as the ideal value even one of the modules in CHBR is facing the load-removed problem.

By using the voltage balance strategy of LCM, the problem of voltage imbalance occurring in three-phase cascaded rectifiers has been solved properly. With the lower modulation depth, the efficiency of the strategy is shown to be better and stronger. The strategy can work reliably and quickly no matter facing the problem as load-removed change or the ordinary operating conditions.

The limitation of the proposed DC-port voltage balance strategy is calculated and proved, in a three-module CHBR, the LCM could balance the DC-port voltage while one module facing the load-removed situation under 0.83 modulation depth.

This paper provides a useful and particular voltage balance strategy which can be used in the topology of three-phase cascaded rectifier. The value of the strategy is that a brief and reliable voltage balance method in the power electronic devices can be achieved. What is more, facing the problem, such as load-removed, in outport, the strategy can response quickly with no switch jump and switch frequency rising.

The purpose of this paper is to examine how Si-shu, a traditional form of local, private education grounded in classical instruction, responded to the rapid modernization of education during the late Qing dynasty and early Republic of China and to explain why these schools, once extraordinarily adaptable, finally disappeared.

The authors have examined both primary and secondary sources, including government reports, education yearbooks, professional annals, public archives, and published research to analyze the social, political and institutional changes that reshaped Si-shu in the context of China's late-19th- and early-20th-century educational modernization.

Si-shu went through four stages of institutional change during the last century. First, they faced increased competition from new-style (westernized) schools during the late Qing dynasty. Second, they engaged in a process of intense self-reform, particularly after the Xinhai Revolution of 1911. Third, they were marginalized by the new educational systems of the Republic of China, especially the Renxu School System of 1922 and the Wuchen School System of 1928. Finally, after the foundation of the People's Republic of China in 1949, they were considered remnants of feudal culture and forcibly replaced by modern schools.

This paper brings hitherto unexplored Chinese sources to an English-speaking audience in an effort to shed new light on the history of traditional Chinese education. The fate of Si-shu was part of the larger modernization of Chinese education – a development that had both advantages and disadvantages.

This study seeks to investigate how leader ability and diverse organisational cultures (OC) act to influence employee creativity in manufacturing organisations. By leveraging the multifaceted nature of the competing values framework (CVF), this study examines the growing deterioration of employee creativity through the lens of four OC quadrants within the Nigerian manufacturing industry and further investigates how distinct OCs and leader ability can aid to bolster employee creativity. The CVF is a model used to assess organisational cultures, irrespective of their industry, for the overarching purpose of improving organisational performance.

The target population consists of employees of research and development (R&D) and information technology (IT) in the headquarters of 21 manufacturing organisations. Our useable sample consisted of 439 responses from the Nigerian manufacturing industry.

Results indicated that leader ability and adhocracy OC have positive effects on employee creativity. Market and clan OC have negative effects on employee creativity. Likewise, leader ability dampens the effects of adhocracy OC on employee creativity and reinforces the market OC effect on employee creativity.

This study provides novel insights that challenges several controversial and contemporary postulations of extant research which theorise the OC–employee creativity relationships. By leveraging the construct of leader ability, unique contributions are also made to provoke congruence.

The purpose of this paper is to investigate whether supplier dependence is related to innovation in supplier firms. Drawing on resource dependence theory, the authors hypothesized that supplier dependence has both positive and negative relationships to the quantity and quality of innovation.

The study is based on data collected from US companies. Negative binomial regression analysis was used to test the proposed hypothesis.

The authors found that the quantity of innovation of a supplier firm initially decreased and then increased with the extent of the dependence upon major customers. This finding supports the idea that the benefits of supplier dependence mitigate the negative outcomes of dependence upon major customers.

This study extends the literature on supplier dependence by empirically examining the relationship between supplier dependence and the quantity and quality of innovation within the context of high-technology industries. The authors provide a holistic understanding of the value of the dependent relationship in boosting innovation in the context of supply chain management.