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Laser cleaning, as a new type of cleaning technology, has the advantages of environment-friendliness, better selectivity, better controllability and higher efficiency compared to traditional chemical cleaning or grinding. This paper aims to use ultra-fast surface laser cleaning equipment built in laboratory to study the influence of different energy density (7.6, 11.5 and 15.3 J/cm²) on corrosion resistance of the aluminum alloy A7N01P-T4, a high-speed train body material.

SEM, white light interferometer, EDS and XPS were used to analyze the surface morphology, roughness, element content and oxide layer composition of aluminum alloy before and after cleaning. The corrosion resistance was studied by electrochemical experiments and exfoliation corrosion experiments.

The results showed that new oxide scale was formed on the surface after laser cleaning. The changes of surface roughness and chemical composition of oxide scale made a significant influence on corrosion behaviors. Better corrosion resistance was obtained with the energy density increased, and at the energy density of 11.5 J/cm², aluminum alloy exhibited the best corrosion resistance.

The paper only studies specific aluminum alloys and is not universal. Laser cleaning equipment is set up for the laboratory and has not yet been put into industrial production.

This paper indicated that ultra-fast laser processing was a new direction for the development of industrial equipment surface cleaning and carried out ultra-fast laser of aluminum alloy surface cleaning had certain research significance for its corrosion resistance.

Compared with the conventional cleaning methods such as air abrasives grinding or chemical cleaning, laser cleaning has advantages of environment-friendliness, better selectivity, better controllability and higher efficiency. Laser cleaning can not only protect the environment, but also improve cleaning efficiency.

Changes in the surface of aluminum alloys after ultra-fast surface laser treatment were found, and the mechanism of changes in aluminum alloy corrosion properties was clarified.

Current practices for inspecting highway construction predominantly rely on manual processes, which result in subjective assessments, errors and time inefficiencies. The purpose of this study is to address the inefficiencies and potential inaccuracies inherent in manual highway construction inspections. By leveraging computer vision and ontology reasoning, the study seeks an automated and efficient approach to generate structured construction inspection knowledge in the format of checklists for construction activities on highway construction job sites.

This study proposes a four-module framework based on computer vision and ontology reasoning to enable the automatic generation of checklists for quality inspection. The framework includes: (1) the interpretation of construction scenes based on computer vision, (2) the representation of inspection knowledge into structured checklists through specification processing, (3) the connection of construction scenes and inspection knowledge via ontology reasoning and (4) the development of a prototype for the automatic generation of checklists for highway construction.

The proposed framework is implemented across four distinct highway construction scenarios. The case demonstrations show that the framework can interpret construction scenes and link them with relevant inspection knowledge automatically, resulting in the efficient generation of structured checklists. Therefore, the proposed framework indicates considerable potential for application in the automatic generation of inspection knowledge for the quality inspection of highway construction.

The scientific and practical values of this study are: (1) the establishment of a new method that promotes the automated generation of structured inspection knowledge for highway construction by integrating computer vision and ontology reasoning and (2) the development of a novel framework that provides efficient and immediate access to inspection knowledge related to what needs to be inspected at highway construction job sites.

Lesson study (LS) is generally regarded as a pathway for teachers' professional development and a method for teachers' instructional research. LS has been regarded as having the potential to drive large-scale reform but little is known about how it does so from a district level. Therefore, this paper aims to reveal how lesson study promote district education reform.

This study offers an in-depth case study of how District Y of Shanghai, China, took LS as the primary method in promoting its District Project of Building Curriculum Leadership in Schools. By analyzing the key project documents and achievements in project promotion, and interviews with the major Project leaders at District and school levels, this study explored the practice and impact of LS as a tool to promote district reform.

In the District Project, LS has been a medium to address each individual school's real problems of practice and turn them into reform vision and reform will in alignment with District goals. Five levels of school curriculum texts have been planned, designed, translated, implemented, reflected on, updated and mutually adjusted systematically through LS to ensure consistency in transforming District reform vision into classroom practice. Different models of teaching-research community building were found in sampled project schools and professional expertise was built with district support to promote reform. The curriculum leadership development through LS has shaped reform leader schools and formed a collection of LS exemplars circulated in schools as high-quality curriculum packages, which laid the foundation for district-wide reform.

The innovative practice of LS in China's education reform has expanded its reach from within one classroom to the entire district curriculum system and made it an important tool to drive large-school district-based education reform.

Fixed mode noise and random mode noise always exist in the image sensor, which affects the imaging quality of the image sensor. The charge diffusion and color mixing between pixels in the photoelectric conversion process belong to fixed mode noise. This study aims to improve the image sensor imaging quality by processing the fixed mode noise.

Through an iterative training of an ergoable long- and short-term memory recurrent neural network model, the authors obtain a neural network model able to compensate for image noise crosstalk. To overcome the lack of differences in the same color pixels on each template of the image sensor under flat-field light, the data before and after compensation were used as a new data set to further train the neural network iteratively.

The comparison of the images compensated by the two sets of neural network models shows that the gray value distribution is more concentrated and uniform. The middle and high frequency components in the spatial spectrum are all increased, indicating that the compensated image edges change faster and are more detailed (Hinton and Salakhutdinov, 2006; LeCun et al., 1998; Mohanty et al., 2016; Zang et al., 2023).

In this paper, the authors use the iterative learning color image pixel crosstalk compensation method to effectively alleviate the incomplete color mixing problem caused by the insufficient filter rate and the electric crosstalk problem caused by the lateral diffusion of the optical charge caused by the adjacent pixel potential trap.

Numerous studies highlight the importance of knowledge transfer between projects, but the influence factors are still debated. As a contribution to the identified gap, the purpose of this paper is to investigate the role of organizational context, project characteristics and social relations in the inter-project knowledge transfer within the project-based organizations (PBOs).

This paper collects the data through 268 sample questionnaires from Chinese construction sectors and applies the structure equation modeling to analyze knowledge transfer between projects in PBOs.

The results indicate the organizational context (meeting system, reward system and shared culture) and project characteristics (similarity and urgency) are antecedents affecting social relations (communication, trust and reciprocity) between project teams, and their social relations further influence the effectiveness of inter-project knowledge transfer.

The study highlights the role of organizational context and effect of social relations for inter-project knowledge transfer in PBOs, and provides valuable suggestions for knowledge and project management in PBOs.

This paper aims to explore the adsorption kinetics of syringin from Syringa oblata Lindl. leaves on macroporous resin and develop an efficient, simple and recyclable technology for the separation and purification of syringin.

Static adsorption and desorption properties of six resins were tested to select a suitable resin for the purification of syringin. Langmuir and Freundlich isotherm models were used to estimate the adsorption behavior of syringin on AB-8 resin. Breakthrough point and eluent volume were determined by dynamic adsorption and desorption tests. High-performance liquid chromatography-electrospray ionization-mass spectrometry was applied to identify the syringin in the purified product [syringin product (SP)]. Antioxidant and antibacterial activities of SP in vitro were evaluated by free radical scavenging ability and biofilm formation inhibitory tests.

AB-8 exhibited the most suitable adsorption and desorption capacity. Adsorption isotherm parameters indicated favorable adsorption between AB-8 and syringin. The optimal results were as follows: for adsorption, the sample concentration was 1.85 mg/mL, the sample volume was 3.5 bed volume (BV), the flow rate was 0.5 mL/min; for desorption, the ethanol concentration was 70%, the elution volume was 2.5 BV, the elution velocity was 1.0 mL/min. SP with 80.28% syringin displayed the potent antioxidant activities and inhibitory effects on biofilm formation of Streptococcus suis.

To the best of authors’ knowledge, there are no reports on purifying syringin from Syringa oblata Lindl. leaves using macroporous resins. This paper may also provide a theoretical reference for the purification of other phenylpropanoid glucosides.

Existing research on collaborative innovation mechanisms from the perspective of global operation is very limited. This paper aims to address the research gap by studying the factors influencing globally distributed teams’ innovation performance, especially how effective knowledge sharing between distributed teams promotes collaborative team innovation.

This research proposes a model to investigate how collaborative knowledge sharing affects global operations [team dispersion, task orientation, information and communication technology (ICT) usage] and innovation performance based on the data collected from 167 managers in 40 local Chinese IT and offshoring firms. Using the theory of Cognitive Diversity and Innovation Diffusion and Synergy, separate hierarchical regression analysis was used to test the proposed model.

The findings of this study demonstrate that effective collaborative knowledge sharing plays a crucial role in enhancing innovation performance in a global operation. Specifically, innovation capacity can be improved by task orientation, ICT usage and team dispersion.

This research study contributes to the development of global distributed operations and innovation among distributed teams in multinational corporations.

This study aimed to explore two questions. The first is why employees become emotionally exhausted when faced with after-hours electronic communication. The second is how can emotional exhaustion caused by after-hours electronic communication be alleviated?

Our research was based on conservation of resources theory, social exchange theory, and relative deprivation theory. We surveyed 241 employees using three waves of data collection to examine the impact of after-hours electronic communication expectations on their emotional exhaustion. We also explored the mediating effects of relative deprivation and obsessive passion from a cognitive-affective perspective and the moderating effect of leader-member exchange.

The results indicate that after-hours electronic communication expectations lead to employee emotional exhaustion, which is mediated by obsessive passion and relative deprivation. The leader-member exchange negatively moderated after-hours electronic communication expectations and relative deprivation but positively moderated after-hours electronic communication expectations and obsessive passion, thereby alleviating employee emotional exhaustion.

In exploring the influence mechanism of after-hours electronic communication expectations on emotional exhaustion from a cognitive-affective perspective, our study went beyond the limitations of analysis from a single perspective. A comparison of the two pathways indicated that cognition (relative deprivation) is more likely to lead to emotional exhaustion, which validates the view that individuals can ultimately analyse their behaviours rationally. By exploring the moderating effect of leader-member exchange, we provide a theoretical basis for organisations to take measures to alleviate the negative emotions caused by after-hours electronic communication.

This study investigates how reward type (single vs. plural), reward characteristic (utilitarian vs. hedonic) and product involvement (high vs. low) affect the design of reward programs.

A 2 ✕ 2 ✕ 2 fractional factorial experimental design is constructed to explore the main factors influencing the effectiveness of reward programs on a sample of 436 Chinese customers.

The results indicate that reward type is an important determinant of customers' preference toward reward programs. Plural rewards are preferable to a single reward when the alternatives provide the same benefits, particularly in the low level of product involvement. In the high level of product involvement, reward characteristic has a significant effect on customers' preference. Hedonic rewards are more effective in building a program's value than utilitarian rewards. Moreover, reward characteristic interacts with reward type, positively impacting customers' preference toward reward programs.

This study suggests that managers should consider the effects of reward type, reward characteristic and product involvement to formulate attractive reward programs for sustainable business in China.

Due to the conflicts between left turn traffic and opposite straight-going traffic in urban traffic network, some of the traffic lanes cannot be used to discharge vehicles during its green phases and the intersection capacity can be greatly reduced. This study/paper aims to reduce the effect of conflicts and increase its capacity through the reasonable pre-signal phase time with the exchangeable lanes.

This paper took into consideration various influence factors to intersection capacity and formulated the capacity optimization model based on 0-1 mixed-integer programming model. This model is efficiently solved by standard branch-and-bound algorithms.

The authors took an intersection as an example and solved the optimal signal timing and entrance lane capacity via this model. Then, simulations were carried out to verify the effect of the exchangeable lanes strategy of this intersection through the simulation software VISSIM and take the traffic volume and delay as outputs, which indicated that this model has better performance.

The front-end control strategy can not only exploit the full potential of the intersection but also significantly improve the operational efficiency of the intersection. It plays a positive role in improving urban intersection congestion.