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Unconventional machining processes, particularly ultrasonic vibration cutting (UVC), can overcome such technical bottlenecks. However, the precise mechanism through which UVC affects the in-service functional performance of advanced aerospace materials remains obscure. This limits their industrial application and requires a deeper understanding.

The surface integrity and in-service functional performance of advanced aerospace materials are important guarantees for safety and stability in the aerospace industry. For advanced aerospace materials, which are difficult-to-machine, conventional machining processes cannot meet the requirements of high in-service functional performance owing to rapid tool wear, low processing efficiency and high cutting forces and temperatures in the cutting area during machining.

To address this literature gap, this study is focused on the quantitative evaluation of the in-service functional performance (fatigue performance, wear resistance and corrosion resistance) of advanced aerospace materials. First, the characteristics and usage background of advanced aerospace materials are elaborated in detail. Second, the improved effect of UVC on in-service functional performance is summarized. We have also explored the unique advantages of UVC during the processing of advanced aerospace materials. Finally, in response to some of the limitations of UVC, future development directions are proposed, including improvements in ultrasound systems, upgrades in ultrasound processing objects and theoretical breakthroughs in in-service functional performance.

This study provides insights into the optimization of machining processes to improve the in-service functional performance of advanced aviation materials, particularly the use of UVC and its unique process advantages.

3-ply cross-laminated timber (CLT) is used to investigate the thermo-mechanical performance of intermediate-size assemblies comprised of T-shaped welded slotted-in steel doweled connections and CLT beams at ambient temperature (AT), after and during non-standard fire exposure.

The first set of experiments was performed as a benchmark to find the load-carrying capacity of the assembly and investigate the failure modes at AT. The post-fire performance (PFP) test was performed to investigate the residual strength of the assembly after 30-min exposure to a non-standard fire. The fire-performance (FP) test was conducted to investigate the thermo-mechanical behavior of the loaded assembly during non-standard fire exposure. In this case, the assembly was loaded to 67% of AT load-carrying capacity and partially exposed to a non-standard fire for 75 min.

Embedment failure and plastic deformation of the dowels in the beam were the dominant failure modes at AT. The load-carrying capacity of the assembly was reduced to 45% of the ambient capacity after 30 min of fire exposure. Plastic bending of the dowels was the principal failure mode, with row shear in the mid-layer of the CLT beam and tear-out failure of the header sides also observed. During the FP test, ductile embedment failure of the timber in contact with the dowels was the major failure mode at elevated temperature.

This paper presents for the first time the thermo-mechanical performance of CLT beam-to-girder connections at three different thermal conditions. For this purpose, the outside layers of the CLT beams were aligned horizontally.

1. Load-carrying capacity and failure modes of CLT beam-to-girder assembly with T-shaped steel doweled connections at ambient temperature presented.

2. Residual strength and failure modes of the assembly after 30-min partially exposure to the non-standard fire provided throughout the post-fire performance test.

3. Fire resistance of the assembly partially exposed to the non-standard fire highlighted.

Load-carrying capacity and failure modes of CLT beam-to-girder assembly with T-shaped steel doweled connections at ambient temperature presented.

Residual strength and failure modes of the assembly after 30-min partially exposure to the non-standard fire provided throughout the post-fire performance test.

Fire resistance of the assembly partially exposed to the non-standard fire highlighted.

Thermomechanical behavior of intermediate-size beam-to-wall assemblies including Glulam-beams connected to cross-laminated timber (CLT) walls with T-shape steel doweled connections was investigated at ambient temperature (AT) and after and during non-standard fire exposure.

Three AT tests were conducted to evaluate the load-carrying capacity and failure modes of the assembly at room temperature. Two post-fire performance (PFP) tests were performed to study the impact of 30-min (PFP30) and 60-min (PFP60) partial exposure to a non-standard fire on the residual strength of the assemblies. The assemblies were exposed to fire in a custom-designed frame, then cooled and loaded to failure. A fire performance (FP) test was conducted to study the fire resistance (FR) during non-standard fire exposure by simultaneously applying fire and a mechanical load equal to 65% of the AT load carrying capacity.

At AT, embedment failure of the dowels followed by splitting failure at the Glulam-beam and tensile failure of the epoxy between the layers of CLT-walls were the dominant failure modes. In both PFP tests, the plastic bending of the dowels was the only observed failure mode. The residual strength of the assembly was reduced 14% after 30 min and 37% after 60 min of fire exposure. During the FP test, embedment failure of timber in contact with the dowels was the only major failure mode, with the maximum rate of displacement at 51 min into the fire exposure.

This is the first time that the thermomechanical performance of such an assembly with a full-contact connection is presented.

There are certain differences in the production products of enterprises. What are the impacts of product differentiation on the iron and steel industry? Based on the macro background of CO₂ emission reduction, this paper aims to analyze the economic benefits and environmental changes of the iron and steel industry under the dual influence of CO₂ emission reduction policy and product differentiation policy.

Taking the basic data of iron and steel industry in six regions of China as an example, this paper constructed an extended two-stage dynamic game model to analyze the impact of product differentiation and carbon tax policy on the production, economic indicators and CO₂ emission levels for the overall industry and regional enterprises.

As the CO₂ emission reduction target increased, the unit carbon tax and total tax increased, whereas the macro-environmental losses, social welfare, consumer surplus and outputs decrease. Emission reduction pressures and other economic indicators showed obvious regional differences. Differentiated products promoted various indicators of enterprises and industries; higher degrees of product differentiation resulted in greater promoting effects on economic indicators.

This paper constructed multiple emission reduction and production backgrounds, and discusses the impact of the comprehensive implementation of these policies, which has been practically absent in previous studies. The results of this study are consistent with the current industrial policy for stable production and environmental protection, and also provides a reference for the formulation of detailed policies in the future.

Environmental problems such as CO₂ (Carbon Dioxide) emissions have seriously affected the development of the steel industry, which has urged the industry to adopt a more effective emission reduction policy. This paper aims to analyze the impact of various CO₂ emission reduction policies combinations on the economic benefits and environmental changes of the steel industry and to determine the scope of application.

To compare the impact and applicable implementation conditions, a production decision game model that incorporates these two policies has been constructed. Short-, medium- and long-term constraints are set on the emission reduction indicators and the indicators’ changes under various scenarios are compared.

In the case of a single emission reduction policy, the carbon trading (CT) mechanism is better than the carbon tax mechanism. The mixed carbon trading mechanism is superior to the mixed carbon tax mechanism in terms of total output and subsidies, but worse in terms of overall social welfare, producer surplus and macro losses.

This paper constructs multiple emission reduction and production backgrounds and discusses the impact of the comprehensive implementation of these policies, which is practically absent in previous studies. It is in line with the current industrial policy for stable production and environmental protection and also provides a reference for the formulation of detailed policies in the future.

This paper aims to assess the economic impacts of the European Union’s Carbon Border Adjustment Mechanism (CBAM) on Vietnam.

We constructed a general equilibrium model to assess the economic impacts of the CBAM on the macroeconomic indicators of Vietnam. We also constructed a generic partial equilibrium model to provide a zoomed-in view of the impact on each group of CBAM-targeted commodities, which is not possible in the general equilibrium model. Both the general equilibrium and the partial equilibrium models were calibrated with publicly available data and a high number of value sets of hyperparameters to estimate the variations of the estimated impacts.

The results suggest that the current form of the EU’s CBAM is unlikely to produce substantial effects on the overall economy of Vietnam, mainly because the commodities affected by it represent a small portion of Vietnam’s exports. However, at the sectoral level, the CBAM can reduce production outputs and export values of steel, aluminium, and cement.

The CBAM by itself may not lead to significant decreases in greenhouse gas emissions, but it could provide a rationale for implementing carbon pricing strategies, which might result in more significant economic effects and help in reducing greenhouse gas emissions. This highlights the necessity of supplementary policies to tackle global climate change.

We constructed economic models to evaluate the impacts of the European Union’s Carbon Border Adjustment Mechanism on Vietnam, both at the macroeconomic level and zooming in on directly impacted groups of commodities.

As the contradiction between economic development, resource and environment has become increasingly prominent, low-carbon competitiveness has received worldwide focus. This study aims to examine low-carbon competitiveness in 31 provinces (cities and regions) of China.

An evaluation index system for low-carbon competitiveness in China has been constructed, which is composed of 25 economic, social, environmental and policy indicators. To study the state of low-carbon competitiveness and resistance to China’ development of low-carbon competitiveness, this study uses a combination of the catastrophe progression model, the spatial autocorrelation model and the barrier method.

China’ low-carbon competitiveness gradually decreases from coastal to inland areas: the Tibet and Ningxia Hui autonomous regions are the least competitive regions, while the Shandong and Jiangsu provinces are the most competitive areas. The spatial correlation of the 31 provinces’ low-carbon competitiveness is very low and lacks regional cooperation. This study finds that the proportion of a region’ wetland area, the proportion of tertiary industries represented in its GDP and afforestation areas are the main factors in the development of low-carbon competitiveness. China should become the leader of carbon competitiveness by playing the leading role in the Eastern Region, optimizing the industrial structure, improving government supervision and strengthening environmental protection.

The paper provides a quantitative reference for evaluating China’ low-carbon competitiveness, which is beneficial for environmental policymaking. In addition, the evaluation and analysis methods offer relevant implications for developing countries.

A low-carbon economy is the pressing need of the hour. Despite several efforts taken by the government and large corporations, there is still research to be conducted exploring the role of top management commitment in translating external pressures into responses that help to build low-carbon emissions in supply chains.

The authors have grounded their framework in institutional theory, agency theory and contingency theory. On the basis of existing literature, four hypotheses were drawn. To test these hypotheses, a questionnaire was developed and pre-tested. Finally, statistical analyses were performed to test the research hypotheses using 176 samples gathered using a pre-tested questionnaire following Dillman’s (2007) total design test method.

The results suggest that coercive pressures and mimetic pressures under the mediating effect of top management commitment have a significant influence on organizational response to low-carbon emissions. The authors further note that supply base complexity has moderating effects on the link between top management commitment and organizational response towards low-carbon emissions.

This study offers valuable insights to those managers and environmental consultants who view supply base complexity as a limitation. However, the results indicate that supply base complexity may help to enhance the effectiveness of the top management commitment on organizational response towards low-carbon emissions.

While most efforts to combat climate change are focussed on energy efficiency and substitution of fossil fuels, growth in the built environment remains largely unquestioned. Given the current climate emergency and increasing scarcity of global resources, it is imperative that we address this “blind spot” by finding ways to support required services with less resource consumption.

There is now long overdue recognition to greenhouse gas emissions “embodied” in the production of building materials and construction, and its importance in reaching targets of net zero carbon by 2050. However, there is a widespread belief that we can continue to “build big”, provided we incorporate energy saving measures and select “low carbon materials” – ignoring the fact that excessive volume and area of buildings may outweigh any carbon savings. This is especially the case with commercial real estate.

As the inception and planning phases of projects offer most potential for reduction in both operational and embodied carbon, we must turn our attention to previously overlooked options such as “build nothing” or “build less”. This involves challenging the root cause of the need, exploring alternative approaches to meet desired outcomes, and maximising the use of existing assets. If new build is required, this should be designed for adaptability, with increased stewardship, so the building stock of the future will be a more valuable and useable resource.

This points to the need for increased understanding and application of the principles of strategic asset management, hitherto largely ignored in sustainability circles, which emphasize a close alignment of assets with the services they support.

Arguably, as the built environment consumes more material resources and energy than any other sector, its future configuration may be critical to the future of people and the planet. In this regard, this paper seeks to break new ground for deeper exploration.

This study aims to provide a novel approach to examining the connection between several aspects of low-carbon supply chain practices (LCSCPs), eco-innovation (EI) and the performance of manufacturing firms in Malaysia.

The current study employed a quantitative research strategy, utilizing survey data collected from a sample of 120 manufacturing firms located in Malaysia. The main aim of this study was to analyze the research framework and test the proposed hypotheses.

The results of the study indicate that EI has a mediating role in the link between LCSCP and manufacturing firm performance (MFP). EI serves as a mediating factor in the association between MFP and four components of LCSCPs, specifically low-carbon product design, low-carbon process improvement, low-carbon purchasing and low-carbon logistics.

The results of this study hold significant potential for supply chain professionals in their endeavors to decrease carbon emissions. Practitioners can help eliminate carbon footprints (CFs) by selecting the right LCSCP techniques that support EI and MFP. When creating low-carbon management methods in supply chain management (SCM), practitioners must take into account the potential mediating role of EI.

To date, this work is one of the first efforts to investigate the role of EI as a mediator between LCSCP and MFP. Moreover, this research adds to the existing knowledge and improves understanding of how low-carbon development is being implemented in Malaysia, with the ultimate objective of achieving carbon neutrality by 2050.