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The purpose of this study is to develop a transient wheel–rail rolling contact model to primarily investigate the rail damage under wet condition when the train passes through the welded joints.

The impact force induced by welded joints is obtained through vehicle–track coupling dynamics. The normal and tangential wheel–rail contact pressures were solved by elastohydrodynamic lubrication (EHL) theory and simplified third-body layer theory, respectively. Then, the obtained tangential pressure and normal pressure were applied to the finite element model as moving loads, simulating cyclic loading. Finally, the shakedown map and critical plane method were used to predict rolling contact fatigue (RCF) and the initiation of fatigue cracks.

The results indicate that RCF will occur and fatigue cracks are more prone to appear on the subsurface of the rail, specifically around 2.7 mm below the rail surface in the vicinity of the welded joint and its heat-affected zone.

The cosimulation of numerical model and finite element model was implemented. The influence of surface roughness and fluids was considered. In this model, the normal and tangential wheel–rail contact pressure, the stress and strain and the rail fatigue cracks were obtained under a rail-welded joint excitation.

This study aims to examine the risk-resistant role of environmental, social and governance (ESG) performance in the capital market, focusing on an organizational standpoint. Furthermore, it aims to offer management decision advice to companies seeking protection against stock market risks. Conclusions obtained through this research have the potential to enrich the economic consequences of ESG performance, provide practical implications for enhancing corporate ESG performance, improving corporate information quality and stabilizing capital market development.

Based on the data of Chinese A-share listed companies from 2009 to 2020, this study examines the risk-resistant function of ESG performance in the capital market. The impact of ESG performance on management behavior is analyzed from the perspective of organizational management and the three mechanisms of pre-event, during the event and post-event.

This paper demonstrates that companies that effectively implement ESG practices are capable of effectively mitigating risks associated with stock price crashes. Heterogeneity analysis reveals that the inhibitory effect of ESG performance on stock price crash risk is more pronounced in nonstate-owned enterprises and enterprises with higher levels of marketization. After controlling for issues such as endogeneity, the conclusions of this paper are still valid. The mechanism analysis indicates that ESG performance reduces the risk of stock price crash through three paths of organizational management: pre-event, during the event and post-event. That is, ESG performance plays the role of restraining managers’ opportunistic behavior, reducing information asymmetry and boosting investor sentiment.

This paper provides new insights into the relationship between ESG performance and stock price crash risk from an organizational management perspective. This study establishes three impact mechanisms (governance effect, information effect and insurance effect), offering a theoretical basis for strategic corporate decisions of risk management. Additionally, it comprehensively examines the contextual differences in the role of ESG performance, shedding light on the specific domains where ESG practices are influential. These findings offer valuable insights for promoting stable development in the capital market and fostering the healthy growth of the real economy.

The purpose of this study is to develop a 3D wheel-rail adhesion model under wet condition, which considers the generated surface roughness topography and the traditional braking procedure for high-speed trains.

Wheel-rail adhesion has an important effect on the braking ability of railway vehicle. Based on the deterministic mixed lubrication approach, the model was solved to get the adhesion characteristics of the train during braking. The elastic deformation was calculated with the discrete convolution and fast Fourier transform method. The simulation results of adhesion coefficient were compared with the experimental values. The wheel-rail adhesion characteristics of train braking at several different initial speeds were investigated. The effects of the time-step length and roughness orientation on the contact load ratio were also discussed.

The results show that the adhesion coefficient of the numerical model is in good agreement with the experimental results. At the instant of braking, the adhesion coefficient drops to a lower adhesion level, the value of adhesion coefficient is lower than 0.06, especially at a higher speed (200, 300 and 400 km/h).

It can provide a better understanding of the low adhesion phenomenon of train braking under wet condition.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-02-2023-0040/

This paper aims to make a comparative study on the latest version of green campus evaluation standard between China and America: Green Campus Evaluation Standard (GB/T51356-2019) and the sustainability tracking, assessment and rating system (STARS 2.2). The differences of evaluation methods and contents are analyzed and their respective characteristics and advantages are sorted out, so as to promote the development of sustainable campus evaluation standards.

The research mainly adopts the method of comparative study, which is carried out from three dimensions, namely, the related policies development of campus construction and world university sustainable rankings; the content of evaluation standards (including evaluation methods and evaluation categories and scores); the characteristics and current application of standards.

There are great differences between the evaluation standards of China and America in organization and participation mode, evaluation method and content. Public engagement, energy and campus engagement are the hot spots. Buildings, energy, food and dining and investment and finance will become the focus of sustainable campus in the future. Specific optimization strategies of key points, evaluation method and content and organization and participation mode of Chinese standard are put forward.

This paper clarifies the advantages and disadvantages of the current global sustainable campus, and provides the basis for the next stage of construction policy. At the same time, it is helpful for all countries, especially China, to formulate construction guidelines that not only meet their own actual needs but also conform to the trend of global sustainable campus development.

The connotation of sustainable campus is enriched, and the evaluation standards of sustainable campus are improved. The development of sustainable campus is promoted, so as to realize the sustainable development goals.

This research expands the scope of the study to the whole campus, rather than just one aspect of campus buildings. It compares the evaluation standard of green campus in China with STARS in the USA, and no longer compares leadership in energy and environmental design for schools. It discusses the campus building’s energy conservation while paying attention to the campus green consciousness, green management and green planning. Based on the relevant data currently used by STARS in the global evaluation, this paper analyzes the hot spots and shortcomings of the current global sustainable campus construction and puts forward some optimization suggestions for China’s green campus evaluation system.

Academic social network site (ASNS) is a new form of academic service in the social media age, and the study of ASNS user behavior is of great significance to academic librarians due to its recent popularity. This research explores the influencing factors of the continuous usage intention of ASNSs.

A survey of academics in China was conducted, and 361 responses were collected and analyzed with a structural equation model, which involves satisfaction, continuous usage intention, expectation confirmation, perceived usefulness (PU), social identity, referent network size and perceived interactivity (PI).

Satisfaction, expectation confirmation, PU, referent network size, social identity and PI significantly impact continuous usage intention. Satisfaction is a mediating variable by which expectation confirmation, PU, referent network size, social identity and other influencing factors affect continuous usage intention. Expectation confirmation and referent network size are two endogenous variables that can explain and predict the continuous usage intention of ASNSs.

Existing research does not consciously distinguish between adoption, use and continuous use, and only scant studies have conducted empirical research. Further, despite the widespread ASNS usage in China, Chinese scholars' studies are few, as existing studies have mainly focused on users of the UK, the US and India.

The purpose of the work is to verify the offered hypothesis and to evaluate the potential of the modern Russian entrepreneurship in economy’s informatization.

A specially developed proprietary method of evaluation of entrepreneurship’s potential in economy’s informatization and the level of its opening is used, which is created on the basis of the classical method of effectiveness evaluation. The information and analytical basis of studying the entrepreneurship’s potential in economy’s informatization is the materials of the report “The Global Information Technology Report 2016. Innovating in the Digital Economy”, prepared and presented by INSEAD, JOHNSON (Cornell University) and World Economic Forum. The offered proprietary method envisages evaluation of entrepreneurship’s potential in economy’s informatization and the level of its opening on the basis of statistical data according to four criteria: business and innovational environment, business ICT infrastructure, usage of new ICT in business, and economic consequences of using new ICT in business.

The author evaluates the entrepreneurship’s potential in economy’s informatization in modern Russia in 2016 and concludes that entrepreneurship’s potential in modern Russia is rather high, due to which high value of the index of information economy’s formation in Russia is achieved. That is, large entrepreneurship’s potential in economy’s informatization should be viewed as a precondition for information economy’s formation in modern Russia.

The author proves that entrepreneurship’s potential in economy’s informatization is an important component of the process of information economy’s formation in the economic system and can stimulate successful and quick implementation of this process or, quite on the contrary, slow down it rated, based on which it should be paid more attention.

In order to discover a new adsorbent that can be used to purify dye wastewater in the textile and apparel industry, a novel type of graphene oxide/gluten composite material using an improved acid bath coagulation method was synthesized, which can remove methylene blue in an aqueous environment.

After experimentally compounding different ratios of graphene oxide and gluten, the graphene oxide/gluten composite material with 20% graphene oxide content and superlative adsorption effect was chosen. The synthesized material was characterized by different techniques such as FT-IR and SEM, indicating the microstructure of the material and the success of the composite. Various factors were considered, namely, the influence of temperature, dosage, pH and contact time. The isotherms, kinetics and thermodynamic parameters were successively discussed.

The qmax value of 214.29 mg/g of the material was higher compared to the general sorbent, thus, the graphene oxide/gluten composite material was a suitable sorbent for methylene blue removal. Overall, the graphene oxide/gluten composite material can be considered as an effectual and prospective adsorbent to remove methylene blue in the textile and apparel industrial effluent.

Graphene oxide is a potentially excellent sorbent. However, the high dispersibility of GO is detrimental to adsorption, it disperses rapidly in an aqueous solution making separation and recovery difficult. The high load capacity and recyclability of gluten as a colloid make it a suitable carrier for fixing GO. Studies on the combination of GO and GT into composite adsorption material and for the removal of dyes from dyeing wastewater have not been reported. The composite material research on GO and GT can provide new ideas for the research of these kinds of materials and contribute to its wider and convenient application in wastewater treatment.

This study aims to introduce an innovative approach that uses a decoder with multiple layers to accurately identify Chinese nested entities across various nesting depths. To address potential human intervention, an advanced optimization algorithm is used to fine-tune the decoder based on the depth of nested entities present in the data set. With this approach, this study achieves remarkable performance in recognizing Chinese nested entities.

This study provides a framework for Chinese nested named entity recognition (NER) based on sequence labeling methods. Similar to existing approaches, the framework uses an advanced pre-training model as the backbone to extract semantic features from the text. Then a decoder comprising multiple conditional random field (CRF) algorithms is used to learn the associations between granularity labels. To minimize the need for manual intervention, the Jaya algorithm is used to optimize the number of CRF layers. Experimental results validate the effectiveness of the proposed approach, demonstrating its superior performance on both Chinese nested NER and flat NER tasks.

The experimental findings illustrate that the proposed methodology can achieve a remarkable 4.32% advancement in nested NER performance on the People’s Daily corpus compared to existing models.

This study explores a Chinese NER methodology based on the sequence labeling ideology for recognizing sophisticated Chinese nested entities with remarkable accuracy.

The purpose of this paper is to study the behavior of smoke flow in building fires and optimize the design of smoke control systems.

A total of 435 3-D fire simulations were conducted through NIST fire dynamics simulator to analyze thermal behavior of combined buoyancy-induced and pressure-driven smoke flow in complex vertical shafts, under consideration of influence of heat release rate (HRR) and locations of heat sources. This influence was evaluated through neutral pressure plane (NPP), which is a critical plane depicting the flow velocity distributions. Hot smoke flows out of shafts beyond the NPP and cold air flows into shafts below the NPP.

Numerical simulation results show that HRR of heat source has little influence on NPP, while location of heat source can make a significant difference to NPP, particularly in cases of multi-heat source. Identifying the location of NPP helps to develop a more effective way to control the smoke with less energy consumption. Through putting an emphasis on smoke exhausting beyond the NPP and air supplying below the NPP, the smoke control systems can make the best use of energy.

Because of the chosen research approach, the research results may need to be tested by further experiments.

The paper includes implications for the optimization of smoke control systems design in buildings.

This paper fulfills an identified need to research the behavior of hot smoke in building fires and optimize the design of smoke control systems.

The purpose of this paper is to study the behavior of smoke flow in a typical high-rise residential building fire in six common smoke control systems.

The pressure, temperature and CO₂ concentration were used to trace the motion of turbulent smoke flow through CFD.

It is found that the hot smoke could rise up and spread into the indoor space on the upper floors through the staircase. When the pressure in the evacuation staircase is higher, it would be more difficult for the smoke to enter the staircase and transport vertically. On the other hand, the smoke would soon transport to the indoor space on the upper floors horizontally. During this process, the smoke shows a more disorder horizontal transport under the sole effect of thermal buoyancy than the co-existence of thermal buoyancy and the air inlet.

Because of the chosen research approach, the research results may need to be tested by further experiments.

The paper includes implications for the design of smoke control systems and evacuation in a building fire.

This paper fulfils an identified need to study the behavior of smoke in a fire and optimize the design of smoke control systems.