Search results

Identifying and predicting the most helpful reviews has been a focal interest in the fields including information management, e-commerce and marketing, etc. Though many factors are found correlated to the helpfulness of reviews, they may suffer endogeneity problems, as normally the data is observed in the same time window. This paper aims to tackle such a problem by examining the predictive power of different factors on the future increment of review helpfulness.

Adopting a longitudinal data of 443 K empirical business reviews from Yelp.com collected at two different time points, six groups of predictors are extracted from the first snapshot of data to predict the helpfulness increment of old and recent reviews, respectively, between the two snapshots.

It is found that these factors in general are with moderate accuracy predicting the helpfulness increment. A different group of features shows quite different predictive power. The reviewer disclosure information is the most significant factor, while the review readability does not significantly improve the accuracy of prediction.

Instead of the total number of helpful votes observed in the same time window with the explanatory variables, this paper focuses on the future increment of helpful votes observed in the following time window. With such a two-wave data set, the endogeneity problem can be avoided and the explanatory factors for review helpfulness can, thus, be further tested in the prediction scenario.

The purpose of this study is to explore the influence of the sulfate reducing bacteria (SRB) on the corrosion of cupronickel.

Tests monitoring the change in free corrosion potential, linear polarization resistance and electrochemical impedance spectroscopy and examination using the scanning electron microscope and energy spectrum analysis were used to investigate the corrosion behavior of cupronickel in blank medium and in media inoculated with SRB to explore the influence of the SRB on the corrosion behavior of cupronickel alloy.

The results show that SRB can destroy the surface oxide film of cupronickel and significantly reduce the free corrosion potential and polarization resistance of the cupronickel, causing the cupronickel to corrode significantly.

SRB are widely found in the water supply system and is one of the important factors inducing microbial corrosion. This paper verified that SRB promote cupronickel corrosion and explored the influence and mechanism of attack.

Textbook content and curricula are artifacts that can serve as indicators of social contexts and societal values. In this chapter, we use qualitative and quantitative content analysis to examine the content of Chinese language arts textbooks for basic education during a period of curriculum reform in China at the start of the 21st century. Given the important role of the Chinese language arts in the socialization of students into official societal values, this study seeks to provide insight into the nature of the official world view in China and addresses the societal ambivalence between global vs. national/local and traditional knowledge vs. Western/contemporary knowledge. We find that there is a slight increase in themes that reflect contemporary global concerns such as creativity and social justice. We also find that, in the face of the globalizing cultural influences of the new millennium, there is a sustained emphasis on the role of the Chinese language curriculum in the transmission of traditional Chinese cultural values and on the cultivation in Chinese students of an appreciation of their rich cultural traditions.

When college entrance examinations act as gatekeepers to modern-sector jobs, the entire education system then becomes oriented toward these examinations. This occurs at the expense of learning for the sake of learning and other aspects of education that address the holistic development and well-being of students. In recent years in China, there has been growing concern that examination competition has compromised the quality of classroom teaching and learning and is detrimental to the development of skills necessary for the global knowledge economy. These concerns have given rise to a far-reaching set of education reforms known as the New Curriculum reforms which have aimed to move students to the center of teaching and learning and to transform teaching and learning so as to foster such capacities as creativity, innovation, collaboration, self-expression, engagement, enjoyment of learning, inquiry skills, problem-solving abilities, and ability to apply knowledge in practice. In this chapter, we use videotaped high school New Curriculum demonstration lessons to examine teaching and learning practices that are regarded as exemplary in the current reform context. We investigate how teachers are negotiating the competing demands of preparing students for the examinations and addressing the aims of the New Curriculum reforms. The nature of student participation in the classroom emerges in the analysis as a key indicator of the success of this negotiation.

This paper aims at understanding tribological properties of lubricating oils doped with zinc dithiophosphate(ZDDP) with and without electromagnetic field impact.

The friction and wear properties of the oils formulated with zinc butyloctyl dithiophosphate (T202) or zinc dioctyl dithiophosphate (T203) under electromagnetic field or nonelectromagnetic field were evaluated on a modified four-ball tribotester. The characteristics of the worn surfaces obtained from electromagnetic or nonelectromagnetic field conditions were analyzed by scanning electronic microscopy, energy dispersive spectrometer and X-ray photoelectron spectroscopy. This paper focuses on understanding influence of electromagnetic field on lubrication effect of the ZDDP-formulated oils.

The electromagnetic field could effectively facilitate anti-wear and friction-reducing properties of the oils doped with T202 or T203 as compared to those without electromagnetism affection, and the T203-doped oils were more susceptible to the electromagnetic field. The improvement of anti-wear and friction-reducing abilities of the tested oils were mainly attributed to the promoted tribochemical reactions and the modification of the worn surfaces (forming Zn-Fe solid solution) induced by the electromagnetic field.

This paper has revealed that tribological performances of ZDDP-doped oils could be improved by the electromagnetic field and discussed its lubrication mechanisms. Investigating tribological properties of additives from the viewpoint of electromagnetics is a new attempt, which has significance not only for the choose and designing of additives in electromagnetic condition but also for development of tribological theories and practices.

Gas evolution within lithium-ion batteries (LIBs) gives rise to safety concerns that question their applicability. The gas evolution is not only the result but also the inducement of performance deterioration of LIBs. In this paper, the growth characteristics and dynamic behavior of gas bubble on the electrode surface are studied, and the interference mechanism of gas evolution on Li-ion diffusion or Li-ion conduction within LIBs is discussed and validated by the numerical simulations.

First, the mathematical models and simulation method are established. The growth and flow of gas bubble in the serpentine channel on electrode surface, which results from the gas-liquid flow and the effects of surface tension, is modeled by using the multi-phase Navier-Stokes and the volume of fluid method. Integrating Butler–Volmer and Fick’s law, the mathematical model of ions transport in the electrochemical cell is set-up. Second, the motion of gas bubble is tracked, and the variations of bubble shape and characteristic parameters with time are obtained by the computed fluid dynamics (CFD) method.

Based on the CFD results, the battery models and electrochemical simulations are carried out to analyze the ionic transport characteristics. The results show that the microstructural morphology such as the serpentine channel shape and size on electrode surface are important aspects for the gas bubble growth and the local ionic transport. Li ions significantly accumulate at one side of the gas obstacle, hindering the ionic diffusion normally. When the gas bubble blocks the electrolyte, the passage of ions from the positive to the negative is interrupted, and the open circuit zone of the electrochemical cell is formed.

The gas evolution within LIBs is not only a result but also an inducement of its performance deterioration. The primary issues in this study are the growth characteristics and dynamic behavior of gas bubble on the electrode surface, providing the knowledge for the interference mechanism of gas evolution on ionic transport and ultimately leads to significant increase of battery resistance.

Stab-resistant body armor (SRBA) can protect the human body from injury as a result of stabbing by sharp projectiles. However, in its current design SRBA, it has not been widely adopted for use, because of its weight and poor flexibility. Herein, this paper aims to detail a new type of SRBA that is inspired by the armor plating of mammals and is fabricated using laser sintering (LS) technology.

This new type of SRBA was fabricated using LS technology. The laser sintered SRBA was subjected to a stab resistance performance test that conformed to the GA 68-2008 Chinese National Standard. The stab resistance response of the novel structured, stab resistance test plates in this study was analyzed using the using the AUTODYN explicit module in ANSYS-Workbench.

The structure of the novel stab resistance plate was designed and the optimum structural parameters were tested, discussed and achieved. The mechanism of dissipation of the impact energy by the pyramidal structures of the novel SRBA was studied, and it was found that this structure dispersed the kinetic energy of the knife and minimized the structural damage to the plate. Interlinks inspired by the pangolin hierarchy structure were designed and used to fabricate a large piece of laser sintered body armor.

High-performance laser sintered stab resistance plate was produced via the material and structure studies, which could reduce 40 per cent weight on the stab resistance body armor and increase the wearability.

This study aims to investigate the behavior of vegetable oil with two additives. Base oil’s tribological qualities can be improved with the help of several additions. In the present investigation, soybean oil is served as the foundational oil due to its eco-friendliness and status as a vegetable oil with two additives, named polytetrafluoroethylene (PTFE) and molybdenum disulfide (MoS₂).

As additives, PTFE and MoS₂ are used; PTFE is renowned for its anti-friction (AF) properties, while MoS₂ is a solid lubricant with anti-wear (AW) properties. This investigation examines the synergistic impact of AF and AW additions in vegetable oil. The lubricity of the base oil is measured by using a four-ball tester, and the wear properties of the oil at different additive amounts are determined by using a universal tribometer.

PTFE (at 5 Wt.%) and MoS₂ (at 1 Wt.%) were found to improve the tribological performance of the base oil. The weld load is significantly increased when 5 Wt.% of PTFE + MoS₂ is added to the base oil.

A better tribological characteristic can be achieved by combining additives that amount to less than 1% of the base oil. In experiments with highly concentrated MoS₂, the adequate pressure improved dramatically, but the lubricant’s tribological characteristics did not.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2022-0321/

This paper aims to explore the changing pedagogic discourses in China today, using the current wave of English curriculum innovation as a focused case. Given the cross-cultural nature of foreign language education, the change in the English as a foreign language curriculum in China has served as a fertile ground for different pedagogical ideas to emerge and to cross. The new English curriculum in China has endorsed a more communicative and humanistic view of language teaching, encouraging teachers to adopt a task-based approach to organize their classroom teaching. The new English curriculum has aroused a heated debate among Chinese scholars on the suitability of such a Western curriculum idea in the Chinese educational context on the basis of its relation to the Confucian tradition of education, the English as a Foreign Language (EFL) context of China and the danger of post-colonialist imposition.

A critique is conducted on the three areas of controversies by situating the debate in the larger context of the cross-cultural understanding of the Chinese pedagogic discourse in the process of globalization and internationalization.

It is important for China to resist the homogenizing effect of globalization and internationalization in the area of curriculum development; however, being defensive and protective of one’s own and dismissive of others has not been and should not be the attitude of Chinese curriculum reform. The evolution of Chinese pedagogy is not only a result of Western influence but also a result of social change in the process of industrialization (Cheng, 2011). Global trends and national traditions should not be taken as extremes in an incompatible and irreconcilable dichotomy.

The three areas of debates on the new English curriculum can serve as a good lens into the evolving curriculum discourses in China. They reflect the cultural–historical, contextual and critical considerations among Chinese educational scholars in the national curriculum innovation efforts.

This study aims to describe and analyze an innovative mechanism of teacher-led, system-wide professional learning that has been widely adopted since the beginning of the twenty-first century in China – the Master Teacher Studio (MTS).

This paper drew from policy documents, published Chinese literature relating to MTSs and personal fieldwork experience in Shanghai, Guangdong and Zhejiang province.

The article first outlines the context framing the system change, including its policy background and evolution, and then the MTS's purpose, formative process and structure. It finally examines major teacher learning activities and the leadership roles of the MTS hosts (leaders).

This study contributed to the knowledge base of system teacher leaders and how they lead cross-school leading.

The MTS initiative described in this article shows the power of central system leadership to spread and embed effective teacher learning practices at schools.

This article provides implications for understanding and practicing teacher system leadership to support teacher professional learning in different societies.