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The purpose of this paper is to simulate the tension process of tension-type anchor cable and to explore the mechanical characteristics and tension-torsion coupling effect of anchor cable subjected to tension.

ABAQUS numerical software is applied to construct the numerical models of tension-type anchor cables with different diameters. Through explicit contact, the characteristics of contact between grouting body-anchor cable and grouting body-rock mass are determined. Confining pressure is applied to the model through surface pressure, and drawing force is applied to the model by displacement loading so as to simulate the tension process of the anchor cable.

The results show that the stress is transmitted in both axial and radial directions in the anchorage section and distributed in a cone. The shear stress in the grouting body is unevenly distributed, and its peak value increases with the rise in confining pressure and anchor cable diameter. The stress characteristics of torque and axial force are basically consistent and evenly distributed in the free section; they gradually decrease in the anchorage section. Due to the tension-torsion coupling effect, the internal stress characteristics of the anchor cable structure vary. On average, the anchorage performance of each anchor cable model is improved by 6.19%.

The proposed method of numerical modelling is effective in addressing the interface contact between the anchor cable and the grouting body and in solving the problem with convergence of calculation. Compared with the indoor test, this method is more suited to collecting the internal mechanical data of the anchor body.

City wall is an important symbol of ancient Chinese cities with unique geographical and cultural characteristics. Thus, the preservation of this historic landmark is considered significantly important. However, numerous residential construction activities and changes in ecological environment have destructed a great portion of the city walls in recent years. This study looks into the preservation of the ancient city walls from the systematic perspective and in line with the actual characteristics of Longdong Region to provide guideline measures for the protection and restoration of such landmark. Cognition and preservation are adopted extensively to investigate the specific situation of and the factors that influence the ancient city walls in this region. Preservation strategies for the city walls, including the “Axis-Point” system, planning control, and authenticity readability, are presented. The ancient city walls in Longdong Region can be preserved by protecting the entire region, the city, and the main wall body. The systematic method and preservation strategies at the “macro perspective,” “medium perspective” and “micro perspective” levels can solve the preservation problems of the ancient city walls in Longdong Region effectively.

To guide the stable radius clearance choice of water-lubricated bearings for single screw compressors, this paper aims to analyze the effects of turbulence and cavitation on bearing performance under two conditions of specified external load and radius clearance.

A modified Reynolds equation considering turbulence and cavitation is adopted, based on the Jakobsson–Floberg–Olsson boundary condition, Ng–Pan model and turbulent factors. The equation is solved using the finite difference method and successive over-relaxation method to investigate the bearing performance.

The turbulent effect can increase the hydrodynamic pressure and cavitation. In addition, the turbulent effect can lead to an increase in the equilibrium radius clearance. The turbulent region exhibits a higher load capacity and cavitation rate. However, the increased cavitation negatively impacts the frictional coefficient and end flow rate. The impact of turbulence increases as the radius clearance decreases. As the rotating speed increases, the turbulence effect has a greater impact on the bearing characteristics.

The research can provide theoretical support for the design of water-lubricated journal bearings used in high-speed water-lubricated single screw compressors.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2024-0029/

To maximize health synergistic benefits and provide a scientific foundation for enhancing air pollution control policies, this research proposed a causal inference framework with a decomposition ensemble prediction model for comprehensive policy assessment.

We introduced the CD-OASVR-Ensemble-CC method, a policy assessment approach that combined machine learning-based decomposition ensemble prediction (CD-OASVR-Ensemble) with counterfactual contrast (CC) analysis. The CD-OASVR-Ensemble model incorporated support vector regression (SVR) optimized through swarm intelligent optimization algorithms (OA), complete ensemble empirical model decomposition of adaptive noise (CD) and a linear ensemble model (Ensemble). This approach was applied to analyze patterns in historical PM2.5 data and predict the future trend. The predicted PM2.5 served as a counterfactual trend, enabling an evaluation of the policy’s environmental and health effects.

Analysis of prediction errors confirmed the proposed CD-OASVR-Ensemble model’s accuracy and robustness in predicting PM2.5 levels. The findings indicated that the implementation of “Regulation 2019” led to a significant reduction in PM2.5 concentration, preventing an estimated 7,960 premature deaths and saving approximately 2,602.95 m yuan in health-related economic costs.

This study introduces an innovative framework for evaluating the environmental effect of policies, with a specific emphasis on health synergistic benefits.

The purpose of this paper is to assess China’s urban social assistance policy, mainly by examining the findings of in-depth interviews with urban Dibao recipients in Chengdu about their experiences with social assistance, and by comparing what the social assistance offers with the urban poor households’ actual needs and vulnerabilities.

In this study, the author interviewed 15 people from urban Dibao Households in Wuhou District and Qingyang District of Chengdu, China. The interviews were conducted from April to August in 2013, usually in their homes. The small sample naturally limits generalizations, however it can point to directions for future research.

It is found out that urban Dibao which is the core of social assistance policy provides insufficient cash support and other special assistance programs are more of tokenistic which do not offer much help. Besides, due to lack of psychological aid, many recipients show negative and pessimistic attitudes toward life.

Regarding the assessment of social assistance policy in China, the international literature has shown little interest. Several Chinese scholars have analyzed urban social assistance system, but they tend to examine or assess from the perspective of policy makers and focus on making policy suggestions. Thus, there is not much information about whether what the social assistance offers could meet the urban poor households’ actual needs and vulnerabilities. An interesting endeavor would be to explore and assess the urban social assistance policy from the perspective of the recipients, and this is exactly what this paper aims to do.

The purpose of this paper is to explore the endogenous relationship between production specialisation and market commercialisation with an empirical study of farmers in Northwest China.

The three-stage least squares were used to address simultaneity and over-identification problems in comparison with two-stage least squares (2SLS). The Durbin-Wu-Hausman test was employed to identify the endogeneity of the commercialisation and specialisation variables. The validity, relevance, and strength of the instruments were tested using the Stock-Yogo weak instrument diagnostics test.

A two-way interrelationship between specialisation and commercialisation were confirmed, and suggest that farmers’ decisions on farm commercialisation and production specialisation are actually separate and interacting.

By demonstrating that a virtuous cycle exists between agricultural commercialisation and on-farm specialisation, policies can be formulated to complement these two effects that may help increase small holders’ income. Farmers’ market participation can be indirectly improved by combining market improvement and risk management tools to encourage production specialisation.

The insights of this study cast further light onto the farm market participation theory by emphasising that higher asset endowments enable small farmers to specialise in production with comparative advantage.

Global climate change speeds up ice melting and increases flooding incidents. China launched a sponge city policy as a holistic nature-based solution combined with urban planning and development to address flooding due to climate change. Using Weibo analytics, this paper aims to study public perceptions of sponge city.

This study collected 53,586 sponge city contents from Sina Weibo via Python. Various artificial intelligence tools, such as CX Data Science of Simply Sentiment, KH Coder and Tableau, were applied in the study.

76.8% of public opinion on sponge city were positive, confirming its positive contribution to flooding management and city branding. 17 out of 31 pilot sponge cities recorded the largest number of sponge cities related posts. Other cities with more Weibo posts suffered from rainwater and flooding hazards, such as Xi'an and Zhengzhou.

To the best of the authors’ knowledge, this study is the first to explore the public perception of sponge city in Sina Weibo.

The purpose of this paper is to use the corresponding magnetic sensor and detection method to detect and image the defects of small diameter pipelines. Urban gas pipeline is an energy transportation tool for urban industrial production and social life, which is closely related to urban safety. Preventing the occurrence of urban gas pipeline transportation accidents and carrying out pipeline defect detection are of great significance for the urban economic and social stability. To perform pipeline defect detection, the magnetic flux leakage internal detection method is generally used in the detection of large-diameter long-distance oil and gas pipelines. However, in terms of the internal detection of small-diameter pipelines, due to the heavy weight, large structure of the detection device and small pipe diameter, the detection is more difficult.

In order to solve the above matters, self-made three-dimensional magnetic sensor and three-dimensional magnetic flux leakage imaging direct method are proposed for studying the defect identification. Firstly, for adapting to the diameter range of small-diameter pipelines, and containing the complete information of the defect, a self-made three-dimensional magnetic sensor is made in this paper to improve the accuracy of magnetic flux leakage detection. And on the basis of it, a small diameter pipeline defect detection system is built. Secondly, as detection signal may be affected by background magnetic field interference and the jitter interference, the complete ensemble empirical mode decomposition with adaptive noise method is utilized to screen the detected signal. As a result, the useful signal is reconstructed and the interference signal is removed. Finally, the defect contour inversion imaging of detection is realized based on the direct method of three-dimensional magnetic flux leakage imaging, which includes three-dimensional magnetic flux leakage detection data and data segmentation recognition.

The three-dimensional magnetic flux leakage imaging experimental results shown that, compared to the actual defects, the typical defects, irregular defects and crack groove defects can be analyzed by the magnetic flux leakage defect contour imaging method in qualitative and quantitative way respectively, which provides a new idea for the research of defect recognition.

A three-dimensional magnetic sensor is made to adapt the diameter range of small diameter pipeline, and based on it, a small-diameter pipeline defect detection system is built to collect and display the magnetic flux leakage signal.

Rapid urbanization and development of pilgrimage cities cause significant problems for the environment and society, leading to long-term challenges. Despite several discussions on city sustainability, the literature does not address some of the specific problems of pilgrimage cities. Hence, this study attempts at developing a method to examine the growth pattern and sustainability of pilgrimage cities in southern part of India.

The benchmarking method and the social, economic and environmental dimensions of sustainability are considered to construct the Pilgrimage City Sustainability Index (PCSI). Appropriate variables and categories are identified through a literature review and expert opinion survey. The benchmark values of the variables are derived by contemplating the pilgrimage cities of Tamil Nadu, one of the states with the largest tourist arrivals in India. Subsequently, three prominent pilgrimage cities from Tamil Nadu were chosen for the case study and the method was tested.

The result reveals that the cities investigated are performing above average in the sustainability index, with slight variations in their dimension scores. While the category scores of cities assist in identifying macro-level issues, the variable scores provide an insight into micro-level issues. Furthermore, the gap analysis between the benchmark and the present value of each variable discloses the immediate area of attention in each city. Thus, the cities could set more specific targets, frame strategies and/or collaborate with matching cities to bridge these gaps.

This index assessment provides a comparison of the pros and cons of these pilgrimage cities and helps identify their demand and supply. Policymakers can find appropriate tools and approaches that aid in sustainable urban development and tourism management.

To the best of our knowledge, this is the first study in emphasizing the application of the benchmarking method to assess the sustainability of Indian pilgrimage sites. With appropriate modifications, this method can be used in varied contexts across the globe.