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This paper aims to obtain fire resistance of semi-rigid joints for concrete-filled steel tubular (CFST) composite frames and temperature filed distribution of composite joints in fire.

The temperature filed model of semi-rigid joints to CFST columns with slabs was made by using ABAQUS finite element (FE) software, in considering temperature heating-up stage of fire modelling. The effects of composite slab, fire type and construction location were discussed, and the model was verified by the test results. The temperature distribution of composite joint under three-side or four-side fire condition was studied by the sequentially coupled thermal analysis method. The temperature versus time curves and temperature distribution of various construction and location were analyzed.

The paper provides FE analysis and numerical simulation on temperature field of semi-rigid joints for CFST composite frames in fire. The effects of composite slab, fire type and construction location were discussed, and the model was verified by the test results. It suggests that the temperature distribution of composite joint in three- or four-side fire condition showed a different development trend.

Because of the chosen FE analysis approach, the research results may lack generalizability. Therefore, researchers are encouraged to test the proposed propositions further.

The research results will become the scientific foundation of mechanical behavior and design method of semi-rigid CFST composite frames in fire.

This paper fulfils an identified need to study the temperature field distribution of the semi-rigid joints to CFST columns and investigate the mechanical behavior of the semi-rigid CFST joints in fire.

The spherical hybrid sliding bearings (SHSBs) can be used in ultra-precision and heavy-duty machine tools. However, there is little related research for these bearings. The purpose of this study is to investigate the static characteristics and effect factors affecting SHSBs by fluid lubrication.

Based on the theories of fluid lubrication, the Reynolds equation of general Newtonian fluid is derived to obtain the steady-state lubrication equation. The system is solved by the finite difference method and the relaxation iterative method on the staggered grid to obtain the thickness and the pressure distribution of the oil film. The radial and axial load capacities of SHSBs are determined by the pressure field integration over the spherical surface.

The results show that the parameters such as oil supply pressure, bearing clearance, eccentricity ratio, rotating speed and orifices’ number affecting the static characteristics of bearings are significant and the cross-coupling effect exists.

The lubrication model of SHSB is established to analyze the pressure distribution with a variety of oil film thickness. The laws of oil supply pressure, bearing clearance, eccentricity ratio, rotating speed and orifices’ number on the load capacities are researched.

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.

Under the global climate change, carbon footprint has become a hot issue at home and abroad. However, there is no consensus on the concept, measurement and application of carbon footprint.

In this paper, first, the concept and connotation of carbon footprint are reviewed; then, different methods of carbon footprint measurement are compared, and it is found that “bottom-up” life cycle assessment and “top-down” input–output analysis are applicable to different research scales.

Finally, the problems in the process of carbon footprint assessment in textile industry are analyzed and further research directions are proposed.

Analyzed and further research directions are proposed.

Currently, the Tang tomb mural cultural relic resources are presented in a multi-source and heterogeneous manner, with a lack of effective organization and sharing between resources. Therefore, this study aims to propose a multidimensional knowledge discovery solution for Tang tomb mural cultural relic resources.

Taking the Tang tomb murals collected by the Shaanxi History Museum as an example, based on clarifying the relevant concepts of Tang tomb mural resources and considering both dynamic and static dimensions, a top-down approach was adopted to first construct an ontology model of Tang tomb mural type cultural relics resources. Then, the actual case data was imported into the Neo4J graph database according to the defined pattern hierarchy to complete the static organization of knowledge, and presented in a multimodal form in knowledge reasoning and retrieval. In addition, geographic information system (GIS) technology is used to dynamically display the spatiotemporal distribution of Tang tomb mural resources, and the distribution trend is analysed from a digital humanistic perspective.

The multi-dimensional knowledge discovery of Tang tomb mural cultural relics resources can help establish the correlation and spatiotemporal relationship between resources, providing support for semantic retrieval and navigation, knowledge discovery and visualization and so on.

This study takes the murals in the collection of the Shaanxi History Museum as an example, revealing potential knowledge associations in a static and intelligent way, achieving knowledge discovery and management of Tang tomb murals, and dynamically presents the spatial distribution of Tang tomb murals through GIS technology, meeting the knowledge presentation needs of different users and opening up new ideas for the study of Tang tomb murals.

The purpose of this paper is to examine the factors that influence older adults' intention to use virtual fitting room technology during the COVID-19 pandemic based on the extended technology acceptance model (TAM).

An online survey was conducted with a sample of older adults from 60 to 90 years old (n = 819). A structural equation modeling was conducted to test a proposed research model.

The results revealed that older adults' behavioral intentions were positively influenced by perceived usefulness and ease of use, and fear of infection during the pandemic was significantly related to the perceived usefulness. Fit concern was not significantly related to perceived usefulness of virtual fitting room technology.

This research extends the TAM by adding antecedents to perceived usefulness in explaining older adults' adoption of virtual fitting technology.

This paper aims to present the details of isotactic polypropylene (it-PP) films with a cellular structure (air-cavities) dedicated to pressure sensors. The polymer composites (thin films enriched with 5 and 10 wt% of mineral fillers as Sillikolloid P 87 and glass beads) should exhibit suitable structural elasticity within specific stress ranges. After the deformation force is removed, the sensor material must completely restore its original shape and size.

Estimating the stiffness tensor element (C₃₃) for polymer films (nonpolar space-charge electrets) by broadband resonance ultrasound spectroscopy is a relatively simple method of determining the safe stress range generated in thin pressure sensors. Therefore, ultrasonic and piezoelectric studies were carried out on four composite it-PP films. First, the longitudinal velocity (v_L) of ultrasonic waves passing through the it-PP film in the z-direction (thickness) was evaluated from the ω-position of mechanical resonance of the so-called insertion loss function. In turn, the d₃₃ coefficient was calculated from accumulated piezoelectric charge density response to mechanical stress.

Research is at an early stage; however, it can be seen that the mechanical orientation of the it-PP film improves its piezoelectric properties. Moreover, the three-year electric charge stability of the it-PP film seems promising.

Ultrasonic spectroscopy can be successfully handled as a validation method in the small-lot production of polymer films with the air-cavities structure intended for pressure sensors. The structural repeatability of polymer films is strongly related to a homogeneous distribution of the electric charge on the electret surface.

Resilience concepts in integrated urban transport refer to the performance of dealing with external shock and the ability to continue to provide transportation services of all modes. A robust transportation resilience is a goal in pursuing transportation sustainability. Under this specified context, while before the perturbations, robustness refers to the degree of the system’s capability of functioning according to its design specifications on integrated modes and routes, redundancy is the degree of duplication of traffic routes and alternative modes to maintain persistency of service in case of perturbations. While after the perturbations, resourcefulness refers to the capacity to identify operational problems in the system, prioritize interventions and mobilize necessary material/ human resources to recover all the routes and modes, rapidity is the speed of complete recovery of all modes and traffic routes in the urban area. These “4R” are the most critical components of urban integrated resilience.

The trends of transportation resilience's connotation, metrics and strategies are summarized from the literature. A framework is introduced on both qualitative characteristics and quantitative metrics of transportation resilience. Using both model-based and mode-free methodologies that measure resilience in attributes, topology and system performance provides a benchmark for evaluating the mechanism of resilience changes during the perturbation. Correspondingly, different pre-perturbation and post-perturbation strategies for enhancing resilience under multi-mode scenarios are reviewed and summarized.

Cyber-physic transportation system (CPS) is a more targeted solution to resilience issues in transportation. A well-designed CPS can be applied to improve transport resilience facing different perturbations. The CPS ensures the independence and integrity of every child element within each functional zone while reacting rapidly.

This paper provides a more comprehensive understanding of transportation resilience in terms of integrated urban transport. The fundamental characteristics and strategies for resilience are summarized and elaborated. As little research has shed light on the resilience concepts in integrated urban transport, the findings from this paper point out the development trend of a resilient transportation system for digital and data-driven management.

Knowledge input development and innovation implementation are new features of industrial technology innovation. The purpose of this study is to find the process of coordination and ecological spiral in the ambidextrous innovation of industrial technology.

To design the model of industrial technology ambidextrous innovation based on knowledge ecology spiral, an input-output model of knowledge for ambidextrous innovation and a spiral model of knowledge ecology were constructed based on an improved Lotka-Volterra model. Then, the equilibriums in different knowledge inputs and the spiral evolution of knowledge ecology were analyzed. Finally, the ambidextrous coordination mechanism of the core organization was revealed.

By coordinating the knowledge inputs and the knowledge ecology spiral, enterprises extend the R&D investments in the innovation chain, which will facilitate the knowledge inputs of the exploitative and exploratory innovation. Implementing the ambidextrous coordination in the technology innovation chain and the knowledge ecology chain has the advantage of promoting knowledge inputs, mobility and ecological spiral. Meanwhile, it can achieve the “multi-source, integration and coordination” development of industrial technology innovation.

The two-element innovative knowledge input coordination model and the knowledge ecological spiral model based on the improved Lotka-Volterra model are constructed, which extends the modeling way of the traditional knowledge input-output profit model. It is expected to reduce the amount of knowledge input of a single member and provide theoretical reference for improving the efficiency of knowledge input by constructing the inter-dependent regenerative and inter-generative knowledge interaction.