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Browsing knowledge documents in a peer-to-peer (P2P) environment is difficult because knowledge documents in such an environment are large in quantity and distributed over different peers who organize the documents according to their own views. This paper aims to propose a method for constructing a personal knowledge map for a peer to facilitate knowledge browsing and alleviate information overload in P2P environments.

The research presents a method for constructing a personal knowledge map. The method adopts an ontology-concept-tree-based classification algorithm to recognize a peer’s personal knowledge structure and construct a personal knowledge map, and uses a self-organizing map algorithm to cluster and visualize the knowledge documents. The correctness of the created knowledge map is evaluated with a collection of abstracts of academic papers.

The method for constructing a personal knowledge map is the main finding of this research. The evaluation shows that the created knowledge map is good in quality.

The proposed method provides a way for P2P platforms to understand their users’ knowledge background, as well as to improve the P2P platform environment. However, the proposed method will not help a peer when he has nothing in his individual knowledge document repository (i.e. the “cold start” problem). The method also requires a relatively good ontology base for a P2P document sharing system to use the method effectively.

It is novel that the proposed method organizes the knowledge documents related to a peer’s knowledge background into a personal knowledge map. Moreover, the created knowledge map combines the advantages of a hierarchical display and a map display. It has values for a distributed P2P environment to facilitate users’ knowledge browsing and to alleviate information overload.

Suggested tag was considered as one of the critical factors affecting a user’s tagging behaviour. However, compared to the findings on the suggested tags for the monolingual environment, it still lacks focused studies on the tag suggestions for cross-language information. Therefore, this paper aims to concern with annotation behaviour and psychological cognition in the cross-language environment when suggested tags are provided.

A cross-language tagging experiment was conducted to explore the impact of suggested tags on the tagging results and process. The descriptive statistics of tags, the sources and semantic relations of tags, as well as the user’s psychological cognition were all measured in the test.

The experimental results demonstrated that the multilingual suggested tags could bring some costs to a user’s tagging perception. Furthermore, the language factor of suggested tags led to different paths of tagging imitation (reflected by longer semantic mapping and imitation at the visual level) and different cognitive processes (topic extraction and inference process).

To the best of the authors’ knowledge, this study is one of the first to emphasize the effect of suggested tags during multilingual tagging. The findings will enrich the theories of user-information interaction in the cross-language environment and, in turn, provide practical implications for tag-based information system design.

This paper aims to explore the effect of teacher–student collaboration on academic innovation in universities in different stages of collaboration.

Based on collaboration life cycle, this paper divided teacher–student collaboration into initial, growth and mature stages to explore how teacher–student collaboration affects academic innovation.

Collecting data from National Science Foundation of China, the empirical analysis found that collaboration increases the publication of local (Chinese) papers at all stages. However, teacher–student collaboration did not significantly improve the publication of international (English) papers in the initial stage. In the growth stage, teacher–student collaboration has a U-shaped effect on publishing English papers, while its relationship is positive in the mature stage.

The results offer suggestions for teachers and students to choose suitable partners and also provide some implications for improving academic innovation.

This paper constructed a model in which the effect of teacher–student collaboration on academic innovation in universities was established.

The aim of this study is to investigate the effects of the laser cladding process on the microstructure, hardness and corrosion resistance properties of high-entropy alloys (HEA).

Laser cladding technology was used, using AlCoCrFeNiCu HEA powder as the cladding material. HEA coatings were prepared on the surface of 45 steel using a coaxial powder feeding method. The microstructure, phase composition, hardness and corrosion resistance properties of the HEA cladding layer were analyzed using optical microscopy (OM), X-ray diffractometer, digital microhardness tester and electrochemical workstation.

Laser power affects the coating surface; lower power reveals more visible unmelted powder particles. Higher power results in increased melt width and height, a brighter, smoother surface. Phase structure remains consistent, but the coating hardness is significantly higher than the substrate. The hardness of the melted zone in the substrate peaks at approximately 890.5 HV. The cladding zone hardness is about 60 HV higher than the substrate zone. Electrochemical corrosion parameters of the cladding show that, compared to the substrate, Ecor shifts positively by 113 mV, Icor decreases by one order of magnitude and Rp increases by one order of magnitude. These results indicate that the cladding has superior corrosion resistance to the substrate. The bonding strength between the coating and the substrate is greater than 93.6 MPa.

First, based on preliminary pilot experiments, nine sets of single-factor experiments were designed. Through these experiments, a specimen with relatively favorable cross-sectional morphology was observed. This specimen was then subjected to coating research, revealing that its microstructure and properties had significantly improved compared to the substrate. This enhancement holds remarkable significance for prolonging the service life of components.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2024-0413/

Considering the influence of environmental noise and modeling error during the process of the robotic automatic grinding aero-engine blade, this study aims to propose a method based on the extended state observer (ESO) to reduce the fluctuation of normal grinding force.

First, the measurement range of the six-dimensional force sensor is calibrated according to the maximum acceleration of end-effector and grinding force. Second, the gravity and zero drift compensation model is built to compensate for measurement error. Finally, the switching function is designed based on the difference between the expected grinding force and the actual feedback value. When the value of function stays within the switching band, a nonlinear active disturbance rejection control (ADRC) loop is applied. When the function value reaches outside the switching band, an ESO-based sliding mode control (SMC) loop is applied.

The simulated and experimental results show that the proposed control method has higher robustness compared with proportion-integral-derivative (PID), Fuzzy PID and ADRC.

The processing parameters of this paper are obtained based on the single-factor experiment without considering the correlation between these variables. A new control strategy is proposed, which is not only used to control the grinding force of blades but also promotes the development of industrial control.

ESO is used to observe environmental interference and modeling errors of the system for real-time compensation. The segment control method consisting of ESO-based SMC and ESO-based ADRC is designed to improve the robustness. The common application of the two parts realizes suppression of fluctuation of grinding force.

This study aims to examine the impact of climate change on the total factor productivity (TFP) of tourism in Chinese cities. Using temperature and precipitation as proxies for climate change, the research analyzes both the direct negative effects of climate change on tourism productivity and the positive spillover effects on neighboring cities. In addition, it investigates how geographic location and economic development contribute to the variation in these effects. The study also explores the mechanisms through which government intervention and industrial structure upgrading influence these impacts.

This study uses a spatial Durbin model to analyze the relationship between climate change and tourism TFP in 287 Chinese cities from 2000 to 2020. Panel data is used, with temperature and precipitation serving as proxies for climate change. The model evaluates both the direct and spillover effects of climate change on tourism productivity, while also analyzing the mechanisms through which government intervention and industrial upgrading affect these relationships. The study further considers how geographic location and economic development impact the results.

This study finds that climate change directly reduces tourism TFP, while generating positive spillover effects for neighboring cities. Cities in the eastern and more economically developed regions are more sensitive to climate change, experiencing stronger impacts compared to cities in central and western regions. The findings suggest that government intervention and industrial structure upgrading are important mechanisms through which climate change affects tourism productivity in Chinese cities.

This research fills a gap in the literature regarding how climate change affects tourism productivity in developing countries, particularly in China. By applying a spatial Durbin model and panel data analysis, the study provides empirical evidence on both the direct and spillover effects of climate change on tourism productivity. It highlights the critical role of government intervention and industrial upgrading as mechanisms shaping the impact of climate change, offering new insights for policymakers and tourism businesses to address the challenges posed by climate change and enhance productivity and competitiveness.

本研究旨在探讨气候变化对中国城市旅游全要素生产率的影响。通过温度和降水量作为气候变化的代理变量, 研究分析了气候变化对旅游全要素生产率的直接抑制效应及其对邻近城市的积极溢出效应。此外, 研究考察了地理位置与经济发展水平如何导致这些效应的异质性。通过分析政府干预和产业结构升级的机制, 本研究为气候变化影响旅游全要素生产率的机制分析提供了理论支持, 为提升发展中国家旅游竞争力提供了指导。

本研究采用空间杜宾模型分析2000年至2020年期间, 中国287个城市的气候变化与旅游全要素生产率之间的关系。研究使用面板数据, 温度和降水量作为气候变化的代理变量。模型分析了气候变化对旅游全要素生产率的直接效应与溢出效应, 并研究了政府干预与产业结构升级的机制效应。研究还考察了基于地理位置与经济发展水平的异质性影响, 提供了气候变化对城市旅游全要素生产率影响的综合分析。

气候变化直接抑制旅游全要素生产率, 同时对邻近城市产生积极的溢出效应。东部城市及高经济水平地区对气候变化更为敏感, 影响强于中西部地区。研究发现, 政府干预与产业结构升级是气候变化影响中国城市旅游全要素生产率的关键机制。

本研究填补了气候变化如何影响发展中国家, 尤其是中国, 旅游全要素生产率领域的研究空白。通过运用空间杜宾模型和面板数据分析, 提供了气候变化对旅游全要素生产率的直接效应与溢出效应的实证证据。研究强调了政府干预和产业结构升级作为气候变化影响旅游全要素生产率的主要机制。通过关注区域异质性与经济发展水平, 本研究为旅游企业与政策制定者应对气候变化挑战,提升生产力和竞争力提供了新的思路。

Este estudio examina el impacto del cambio climático en la productividad total de los factores (PTF) del turismo en las ciudades chinas. Utilizando la temperatura y las precipitaciones como indicadores del cambio climático, la investigación analiza tanto los efectos negativos directos del cambio climático sobre la productividad del turismo como los efectos indirectos positivos sobre las ciudades vecinas. Además, investiga cómo la ubicación geográfica y el desarrollo económico contribuyen a la variación de estos efectos. El estudio también explora los mecanismos a través de los cuales la intervención gubernamental y la mejora de la estructura industrial influyen en estos impactos.

Este estudio utiliza un modelo espacial de Durbin (SDM) para analizar la relación entre el cambio climático y la productividad total de los factores del turismo en 287 ciudades chinas entre 2000 y 2020. Se emplean datos de panel, en los que la temperatura y las precipitaciones sirven como variables sustitutivas del cambio climático. El modelo evalúa tanto los efectos directos como los indirectos del cambio climático sobre la productividad del turismo, al tiempo que analiza los mecanismos a través de los cuales la intervención gubernamental y la modernización industrial afectan a estas relaciones. El estudio examina además cómo influyen en los resultados la ubicación geográfica y el desarrollo económico.

El estudio concluye que el cambio climático reduce directamente la productividad total de los factores del turismo, al tiempo que genera efectos indirectos positivos para las ciudades vecinas. Las ciudades de las regiones orientales y económicamente más desarrolladas son más sensibles al cambio climático y experimentan impactos más fuertes que las ciudades de las regiones centrales y occidentales. Los resultados sugieren que la intervención gubernamental y la mejora de la estructura industrial son mecanismos importantes a través de los cuales el cambio climático afecta a la productividad del turismo en las ciudades chinas.

Esta investigación llena un vacío en la literatura sobre cómo el cambio climático afecta a la productividad del turismo en los países en desarrollo, especialmente en China. Aplicando un modelo espacial de Durbin y un análisis de datos de panel, el estudio aporta pruebas empíricas sobre los efectos directos y indirectos del cambio climático en la productividad del turismo. Destaca el papel decisivo de la intervención pública y la modernización industrial como mecanismos que determinan el impacto del cambio climático, ofreciendo nuevas perspectivas a los responsables políticos y las empresas turísticas para afrontar los retos que plantea el cambio climático y mejorar la productividad y la competitividad.

The purpose of this paper is to summarize the advances in grey system theory research and various application achievements in science and engineering. At the same time, it commemorates the 40th anniversary of the birth of grey system theory and the 10th anniversary of Grey Systems–Theory and Application.

Firstly, the innovations of theoretical research in grey system theory were summarized and some of the widely recognized new results are briefly described. By searching and combing the research results of grey system theory in China national knowledge infrastructure (CNKI) database and Web of Science by Institute for Scientific Information (ISI), this paper shows the rapid development trend of grey system theory in the past 40 years, and the successful applications of grey system theory in the fields of social sciences, natural sciences and engineering technologies.

More than 227 thousands literature were found by input 10 phrases such as grey system, grey number and sequence operator etc. in CNKI database. After entering the new century, the number of grey system papers included in CNKI database is increasing rapidly. Since 2008, more than 10 thousands papers have been included per year and more than 15 thousands papers have been included per year since 2014. Grey system method and model are widely used in physics, chemistry, biology and other fields of natural science, as well as transportation, electric power, machinery and other fields of engineering technology, and a large number of valuable results have been achieved.

It can be seen that the grey system theory plays an important role in promoting China’s scientific and technological progress, innovation and development and high-level talent training from tens of thousands of literatures marked with important national science and technology projects and a large number of grey system literatures published by China’s double first-class universities and double first-class discipline construction universities.

Both innovations of theoretical research and practical application play important role in the growth of new theory. The innovations of theoretical research provide methods and tools for practical application, which is conducive to improve application efficiency and broaden application fields. A large number of practical applications needs have become the source of theoretical innovation and the solid background for the birth of theoretical innovation achievements.

The purpose of this paper is to investigate the effect of different heating approaches during thermal rounding of polymer powders on powder bulk properties such as particle size, shape and flowability, as well as on the yield of process.

This study focuses on the rounding of commercial high-density polyethylene polymer particles in two different downer reactor designs using heated walls (indirect heating) and preheated carrier gas (direct heating). Powder bulk properties of the product obtained from both designs are characterized and compared.

Particle rounding with direct heating leads to a considerable increase in process yield and a reduction in powder agglomeration compared to the design with indirect heating. This subsequently leads to higher powder flowability. In terms of shape, indirect heating yields not only particles with higher sphericity but also entails substantial agglomeration of the rounded particles.

Shape modification via thermal rounding is the decisive step for the success of a top-down process chain for selective laser sintering powders with excellent flowability, starting with polymer particles from comminution. This report provides new information on the influence of the heating mode (direct/indirect) on the performance of the rounding process and particle properties.