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The purpose of this paper is to propose a graph-based representation approach for evolutionary knowledge under the big data circumstance, aiming to gradually build conceptual models from data.

A semantic data model named meaning graph (MGraph) is introduced to represent knowledge concepts to organize the knowledge instances in a graph-based knowledge base. MGraph uses directed acyclic graph–like types as concept schemas to specify the structural features of knowledge with intention variety. It also proposes several specialization mechanisms to enable knowledge evolution. Based on MGraph, a paradigm is introduced to model the evolutionary concept schemas, and a scenario on video semantics modeling is introduced in detail.

MGraph is fit for the evolution features of representing knowledge from big data and lays the foundation for building a knowledge base under the big data circumstance.

The representation approach based on MGraph can effectively and coherently address the major issues of evolutionary knowledge from big data. The new approach is promising in building a big knowledge base.

This paper aims to anticipate the possible development direction of WAAM. For large-scale and complex components, the material loss and cycle time of wire arc additive manufacturing (WAAM) are lower than those of conventional manufacturing. However, the high-precision WAAM currently requires longer cycle times for correcting dimensional errors. Therefore, new technologies need to be developed to achieve high-precision and high-efficiency WAAM.

This paper analyses the innovations in high-precision WAAM in the past five years from a mechanistic point of view.

Controlling heat to improve precision is an effective method. Methods of heat control include reducing the amount of heat entering the deposited interlayer or transferring the accumulated heat out of the interlayer in time. Based on this, an effective and highly precise WAAM is achievable in combination with multi-scale sensors and a complete expert system.

Therefore, a development direction for intelligent WAAM is proposed. Using the optimised process parameters based on machine learning, adjusting the parameters according to the sensors’ in-process feedback, achieving heat control and high precision manufacturing.

The purpose of this study is to optimize and improve conventional welding using EMF assisted technology. Current industrial production has put forward higher requirements for welding technology, so the optimization and improvement of traditional welding methods become urgent needs.

External magnetic field assisted welding is an emerging technology in recent years, acting in a non-contact manner on the welding. The action of electromagnetic forces on the arc plasma leads to significant changes in the arc behavior, which affects the droplet transfer and molten pool formation and ultimately improve the weld seam formation and joint quality.

In this paper, different types of external magnetic fields are analyzed and summarized, which mainly include external transverse magnetic field, external longitudinal magnetic field and external cusp magnetic field. The research progress of welding behavior under the effect of external magnetic field is described, including the effect of external magnetic field on arc morphology, droplet transfer and weld seam formation law.

However, due to the extremely complex physical processes under the action of the external magnetic field, the mechanism of physical fields such as heat, force and electromagnetism in the welding has not been thoroughly analyzed, in-depth theoretical and numerical studies become urgent.

Although the impact of carbon emissions regulations is evident to upstream automakers, their influence on downstream B2C car-sharing platforms remains unclear. This article reveals the influence of carbon emission regulations on the performance of supply chain members. In particular, we focused on the decision of B2C car-sharing platforms.

We develop a three-stage dynamic game model consisting of an automaker, a B2C car-sharing platform and consumers.

The carbon emission cap has a critical threshold. Above this threshold, the regulation is ineffective for the platform’s operating model. Below it, the regulation affects the platform, moderated by customers' green awareness. The threshold initially decreases (weakly) and then increases in awareness. Effective caps reduce profits for the manufacturer, B2C car-sharing platform and supply chain, while ineffective caps see higher profits with increased awareness.

Firstly, this paper explores the impact of carbon emission caps on the operational strategies of B2C car-sharing platforms within the sharing economy, complementing existing research. Secondly, it identifies conditions where stricter caps prompt B2C car-sharing platforms to adjust their operational models and offers fresh insights for managers and departments responsible for carbon emission policy formulation. Thirdly, the study uncovers how carbon emission caps affect the performance of supply chain members, providing crucial managerial insights for sustainable operations.

This paper aims to clarify the impact of information asymmetry on users' payment rates and examine the role of perceived uncertainty (PU) and acceptable price (AP) in the relationship between information asymmetry and users' payment rates.

To test the influences of information asymmetry on users' payment rates, this paper collects 18,489 transaction data from the Chinese knowledge payment platform Zhihu with a Python crawler. This paper constructs a mediation model to define the relationship between information asymmetry and users' payment rates by introducing PU and AP as the mediators.

Information asymmetry negatively affects users' payment rates. In addition, PU and AP mediate the information asymmetry in users' payment rates bond.

This study only explores the mediators of the information asymmetry users’ payment rates bond, ignoring the effect of potential moderators, which would be an important direction for future research.

The findings of this paper suggest that information communication is essential in knowledge market transactions. Knowledge providers, as well as knowledge platforms, should enhance information exchange with consumers in order to increase product sales.

This paper provides a new perspective for understanding how information asymmetry affects users' payment rates and helps to guide suppliers to improve product quality. The research framework of this paper is universal to a certain extent.

This paper is one of the first to propose using PU and AP to construct a mediation model to study the information asymmetry between users' payment rates relationship. It provides a new perspective for understanding the channel of information asymmetry in customer behavior.

The purpose of this paper is to investigate investor reactions to financial restatements conditional on disclosures of internal control weaknesses under Section 404 of the Sarbanes-Oxley Act.

The research uses cumulative abnormal stock returns (CARs) as a proxy for investor reactions. Restatements and internal control reports are available on audit analytics. Multivariate regression analyses were used for testing.

Using a sample of restating firms whose original misstatements are linked to underlying internal control weaknesses, the research finds that cumulative abnormal returns for firms disclosing internal control weaknesses in a timely manner is negative in a three-day window around the restatement announcements. The finding indicates that restatements with early disclosure of internal control weaknesses provide more persuasive evidence of the ineffectiveness of a firm’s internal control over financial reporting, rather than early disclosure lowering the information asymmetry between a firm and investors.

This study employs CARs to examine the market reaction to restatements conditional on disclosure of internal control weaknesses.

Further study on reactions by creditors who have access to private information on firms could extend the implications of the finding.

The study contributes to the existing research by documenting that early disclosure of material weaknesses in internal control affects investors’ reactions to financial restatements.

This research aims to investigate the attitudes of young children toward learning science in the early educational grades.

The study involved conducting interviews with seventy-three children attending institutions in Sharjah, United Arab Emirates. The structured interview method was employed to collect valuable data.

The findings of the interviews shed light on the inclination of young children to foster positive attitudes toward science education. These inclinations include the facilitation of knowledge acquisition that enables children to develop skills for applying scientific concepts in real-life contexts, the incorporation of hands-on activities both inside and outside the classroom, and the prioritization of child-centered approaches to learning.

This research aims to explore the attitudes of young children in early educational grades toward learning science. Interviews were conducted with seventy-three children in Sharjah, UAE, using a structured interview method. The findings highlight children’s inclination toward positive attitudes in science education, including the importance of knowledge acquisition for applying scientific concepts in real-life contexts, hands-on activities inside and outside the classroom, and child-centered learning approaches. Based on these findings, the study provides recommendations and conclusions to enhance science education experiences for young children.

World Heritage Sites (WHSs), as crucial tourist attractions, have been demonstrated to promote inbound tourism development; however, no study has analyzed its impact on the origin distribution of inbound tourist flows (ODITFs), leaving a research gap. This study aims to apply power law to assess ODITFs and explore the impact of WHSs on ODITFs.

This study applied the power law of rank-size distribution to calculate ODITFs in 167 countries/regions from 1997 to 2018 and used the panel data model to analyze the effect of WHSs on ODITFs.

WHSs could positively impact ODITFs to be more even. Among them, a cultural WHS shows a more pronounced effect on ODITFs, while the effect of natural WHSs is negligible.

This study advances knowledge about the impact of WHSs on inbound tourism from the standpoint of ODITFs, contributing to the inbound tourist flows theory and tourist attraction theory. In a realistic sense, WHSs, as crucial tourist attractions, could make ODITFs more even, implying that destination management organizations could gain higher growth of incremental tourists from tail markets rather than head markets when increasing tourist attractions.

全球视角下联合国教科文组织世界遗产（whs）对入境游客源地分布的影响

世界遗产地（WHS）作为重要的旅游景点, 已被证明可以促进入境旅游的发展。然而, 目前没有研究分析其对入境游客源地分布（ODITF）的影响。本文旨在应用幂律评估入境游客源地分布, 并探讨世界遗产对入境游客源地分布的影响。

本研究应用序位-规模分布的幂律计算1997年至2018年167个国家/地区的入境游客源地分布, 并使用面板数据模型分析世界遗产对入境游客源地分布的影响。

世界遗产可以对入境游客源地分布产生积极影响, 使入境游客源地分布更加均匀。其中, 世界文化遗产对入境游客源地分布的影响更为显着, 而世界自然遗产的影响可以忽略不计。

本文从入境游客源地分布的角度, 推进了世界遗产对入境旅游影响的认识, 为入境旅游流理论和旅游景点理论做出了贡献。在现实意义上, 世界遗产作为重要的旅游景点, 可以使入境游客源地分布更加均衡, 这意味着目的地管理组织在增加旅游景点时, 可以从尾部市场获得更多的游客增量。

El impacto del Patrimonio de la Humanidad de la UNESCO en la distribución del origen de los flujos turísticos entrantes desde una perspectiva global

Resumen

se ha demostrado que el Patrimonio de la Humanidad de la UNESCO, como atracciones turísticas cruciales, promueven el desarrollo del turismo receptor; sin embargo, ningún estudio ha analizado su impacto en la distribución del origen de los flujos turísticos entrantes (DOFTE), lo que deja un vacío en la investigación. Este documento tiene como objetivo aplicar la ley de potencias para evaluar la DOFTE y explorar el impacto del Patrimonio sobre ella.

este estudio aplicó la ley de potencias de la distribución del tamaño del rango para calcular la DOFTE en 167 países/regiones desde 1997 hasta 2018 y utilizó el modelo de datos de panel para analizar el impacto del Patrimonio de la Humanidad en la DOFTE.

el Patrimonio de la Humanidad podría influir positivamente en la DOFTE para que sea más uniforme. Entre ellos, el Patrimonio cultural muestra un efecto más pronunciado sobre la DOFTE, mientras que el efecto del Patrimonio natural es insignificante.

este artículo avanza en el conocimiento del impacto del Patrimonio de la Humanidad en el turismo entrante desde la perspectiva de la DOFTE, contribuyendo a la teoría de los flujos turísticos entrantes y a la teoría de la atracción turística. En un sentido realista, el Patrimonio de la Humanidad, como atracciones turísticas cruciales, podrían hacer que la DOFTE fuera más uniforme, lo que implica que las organizaciones de gestión de destinos (OGD) podrían obtener un mayor crecimiento de turistas incrementales procedentes de los mercados secundarios en lugar de los mercados principales al aumentar las atracciones turísticas.

This paper aims to prepare high corrosion-resistant chromium-free zinc-aluminum (Zn–Al) coatings reinforced with multi-walled carbon nanotubes (MWCNTs) and nano-ZnO particle composites.

The morphology, composition and corrosion resistance of the coatings were analyzed by electrochemical tests, water contact angle tests, immersion tests, scanning electron microscopy/energy dispersive spectrometer and X-ray diffraction.

The composite coating with 0.3% MWCNTs and 0.5% nano-ZnO particles demonstrated both high shielding performance and cathodic protection performance, which was attributed to the porosity filling of MWCNTs and nano-ZnO particles together with the electrical connection of MWCNTs between the zinc and aluminum powders.

This work laid an experimental foundation for the preparation and corrosion mechanism of high corrosion-resistant chromium-free Zn–Al coating reinforced with MWCNTs and nano-ZnO particles.

The purpose of this paper is to improve the corrosion resistance of stainless-steel bipolar plate by magnetron sputtering.

TiC/amorphous carbon composite film was deposited by magnetron sputter at four different temperature of 25°C, 200°C, 300°C and 400°C. The morphology, composition and structure of the film were characterized by scanning electron microscopy, atomic force microscopy and X-ray photoelectron spectroscopy. And its corrosion behavior was analyzed through electrochemical impedance spectroscopy, potentiodynamic and potentiostatic polarization tests.

A compact TiC/amorphous carbon film was prepared by magnetron sputtering on 316L stainless steel, and the particles of the film were refined with the increase in sputtering temperature. High temperature promoted the formation of TiC and C–C sp² hybrid carbon, but excessively high temperature caused the oxidation of Ti and a significant decrease in sp² hybrid carbon. The corrosion resistance of the film increased with the temperature, and the corrosion current density polarization at 0.86 V and 1.8 V for TiC/a–C film prepared at 400 °C is only 1.2% and 43.2% of stainless steel, respectively.

The corrosion resistance of amorphous carbon films was improved by the doping of Ti carbide, and the appropriate sputtering temperature was obtained.