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From the 2000s onward, construction practices of urban residential buildings in China have shown a material transformation from clay brick to aerated concrete block. Moreover, the consumption of insulating materials for buildings has been increasing due to the new requirements in building energy-saving standards. This transformation and the increased consumption of insulating materials might have a vital impact on a building’s thermal comfort and its associated energy flows. Therefore, the purpose of this paper is to investigate the indoor thermal performance of urban residential buildings built with different materials and further discuss the correlations between indoor thermal comfort and the associated energy input.

This study investigated four residential buildings selected from four residential communities located in the cold climate zone of China. The Integrated Environment Solutions program was used to evaluate the thermal comfort levels and to quantify the operational energy consumption of the case study buildings. Additionally, the University of Bath’s Inventory of Carbon and Energy database was used to estimate the embodied energy consumption and CO₂ emissions.

The study found that materials transition and increasing consumption did not necessarily improve indoor thermal comfort. However, the materials transition has significantly decreased the embodied energy consumption of urban residential buildings. Furthermore, the increased utilization of insulating materials has also decreased the heating and cooling energy consumption. Therefore, overall, the environmental impacts of urban residential buildings have been reduced significantly.

In the future, residential buildings completed in the 1990s will need regular maintenance, such as adding insulation. Residential buildings completed based on the latest energy-saving requirements should optimize their ventilation design, for example, by increasing the ventilation rate and by reducing solar heat gains in the summer.

This paper investigates the effects of the materials change on thermal comfort levels and the environmental impacts of urban residential buildings in the cold climate zone of China, as these have not been the focus of many previous studies.

This paper aims to focus on scrutinizing the economics of greenhouse gas (GHG) emissions in Vietnam's rice production sector.

Using surveyed data from household rice producers, the smallest available production scale, the author delves into the economics of GHG emissions, constructs a data-driven bottom-up marginal abatement cost curve for Vietnam’s rice production, and evaluates the impacts of carbon pricing on production outputs and GHG emissions.

The author’s estimates reveal that the average profit earned per tonne of GHG emissions is $240/tCO2. Notably, the profit earning per tonne of GHG emissions varies substantially across producers, indicating significant opportunities for improvement among low-efficiency producers. The analysis suggests that a reasonable carbon price would yield a modest impact on the national rice output. The quantitative analysis also reaffirms that the primary driver of GHG emissions in Vietnam’s rice production stems from non-energy inputs and industrial processes rather than the utilisation of energy inputs, emphasizing the importance of improving cultivation techniques.

This research is original.

The purpose of this paper is to present original methods related to the modeling of material deposit and associated heat sources for finite element simulation of gas metal arc welding (GMAW).

The filler deposition results from high-frequency impingements of melted droplets. The present modeling approach consists of a time-averaged source term in the mass equation for selected finite elements in the fusion zone. The associated expansion of the mesh is controlled by means of adaptive remeshing. The heat input includes a volume source corresponding to the droplets energy, for which a model from the literature is expressed in coherency with mass supply. Finally, an inverse technique has been developed to identify different model parameters. The objective function includes the differences between calculations and experiments in terms of temperature, but also shape of the fusion zone.

The proposed approach for the modeling of metal deposition results in a direct calculation of the formation of the weld bead, without any a priori definition of its shape. Application is shown on GMAW of steel 316LN, for which parameters of the model have been identified by the inverse method. They are in agreement with literature and simulation results are found quite close to experimental measurements.

The proposed algorithm for material deposit offers an alternative to the element activation techniques that are commonly used to simulate the deposition of filler metal. The proposed inverse method for parameter identification is original in that it encompasses an efficient and convenient technique to take into account the shape of the fusion zone.

Packed salads are popular in many countries of the world. The purpose of this paper is to assess the energy footprint of these products from farm gate to retail gate, compared with unpacked produces distributed by retailers and farmers’ markets in Italy.

Life cycle assessment served as methodological background, even if the analysis was focused on direct and indirect energy consumption. Three supply chains were analysed: packed (P-S) and unpacked (U-S) sold in supermarkets, and unpacked produce sold locally (U-L). Energy inputs were accounted for processing, packaging, refrigeration, transport, and distribution. Data were collected from available literature and from interviews with key experts in the transformation, packaging, and retail sectors. Energy inputs were computed for 1 kg of finished edible product (kg_p).

Packed salads require an elevated energy input ranging from 16 to 37 MJ kg_p−1. Input energy is mostly required for packaging and refrigeration. By comparison, the U-L chain requires about one tenth of the energy (1.8-2.6 MJ.kg_p−1), but local sold produces attain the best performance with only 0.6-1.2 MJ.kg_p−1, since they do not need processing, refrigeration, and disposable packages. Packed products mainly rely on the availability of cheap fossil fuels and all the sector has significantly suffered after the oil shock of 2008. Increasing energy costs may lead the price of the commodity out of the market.

The paper addresses the subject of energy consumption in a popular sector of processed food to which at present little attention has been paid in the domain of food research.

The purpose of this paper is to generate quantitative managerial insights for the improvement of the energy-saving potential and the coordinated development between economic growth and environmental protection.

A novel data envelopment analysis (DEA) model, based on the classical DEA theory, is developed from the perspective of emission reduction.

The empirical results indicate that China’s overall environmental efficiency is low and that there is huge improvement space for energy saving. Under the concerns of emission reduction, the energy-saving potential of the central region exceeds that of both the eastern and western regions. With regard to water, electricity and gas consumption, the electricity-saving potential exceeds the potential for both water saving and gas saving.

Previous studies rarely focused on the energy-saving potential, while considering environmental pollution. This paper applies a novel DEA method to evaluate the energy-saving potential of 30 Chinese provinces for 2015 with a focus on emission reduction concerns. Furthermore, both regional differences and energy type differences of the saving potential were analyzed.

The purpose of this paper is to inform decision makers about the data and information generated by commonly‐used, holistic environmental assessment approaches.

Descriptions of eight types of lifecycle‐based methods are provided: Carbon/Greenhouse Gas (GHG) Management, Ecological Footprint, Energy Assessments, Fuel Cycle Analysis, Life Cycle Assessment (LCA), Life Cycle Risk Management (LCRM), Material Flow Analysis (MFA), and Sustainability Indicators. Example assessments of bio‐based products are provided because of the current environmental and socio‐economic relevance of bio‐feedstocks.

Assessment methods that focus on single impact indicators, such as air emissions (Carbon Management and Fuel Cycle Analysis) and energy, typically show biofuels in a favorable light compared to conventional gasoline (petrol). Ecological Footprint addresses land use implications; LCRM addresses possible impacts to human and ecological health due to chemical contaminant exposure; and MFA identifies areas to improve resource management and decrease the use of natural resources. LCA and Sustainability Indicators cover a wider range of environmental factors.

This study of environmental assessment approaches that incorporate a life cycle perspective revealed the importance of integrating the data and information generated by these disparate evaluations to make quality decisions. Developing such synergies is identified as a research need.

The growing need by decision makers to look broadly at engineered systems led to a proliferation of approaches that are holistic and wide reaching. This paper provides clear descriptions of them to help dispel the potential confusion regarding what the various approaches cover when applying a lifecycle perspective.

The paper bridges the gap between science and the decision‐making process by describing what the various lifecycle‐based methods for environmental assessment can and cannot do. Moreover, it provides evidence that no single tool encompasses all possible environmental impacts.

Enterprises are used to managing quality together with productivity but neglecting environmental management. This involves higher costs and lower benefits than if they were managed jointly. Therefore, efforts must be made to link all of the main aspects of the global performance/efficiency. In recent years several methodologies have been developed and implemented to consider and sort out single aspects of performance (concurrent engineering, quality function deployment, rapid prototyping, lean production, design for assembly and disassembly, total quality management, LCA) seeks to propose a method to attain such a result, within a continuous improvement environment.

The method is based on the correlation between 12 aspects of performance/efficiency in the production processes, general specifications of the project, detail specifications for sub‐systems, and productive modalities.

It is found that this can be done by constructing specific matrices, by utilizing both technical and economic data, which permit to identify the modifications to introduce in the process/product to improve the various aspects of performance.

The way to follow is necessarily the adoption of methodologies able to integrate all aspects, to pursue and achieve an increasing efficiency.

Friction welding is a solid state bonding process, where the joint between two metals has been established without melting the metal. The relative motion between the faying surfaces (surfaces to be joined) under the application of pressure promotes surface interaction, friction and heat generation which subsequently results in joint formation. Stainless steel is an iron based alloy, contains various combinations of other elements to give desired characteristics, and found a wider range of applications in the areas such as petro‐chemical, fertilizer, automotive, food processing, cryogenic, nuclear and beverage sectors. In order to exploit the complete advantages of stainless steels, suitable joining techniques are highly demanded. The Friction welding is an easily integrated welding method of stainless steel, which considered as non‐weldable through fusion welding. Grain coarsening, creep failure and failure at heat‐affected zone are the major limitations of fusion welding of similar stainless steels. Friction welding eliminates such pitfalls. In the present work an attempt is made to investigate experimentally, the mechanical and metallurgical properties of friction welded joints, namely, austenitic stainless steel (AISI 304) and ferritic stainless steel (AISI 430). Evaluation of the characteristics of welded similar stainless steel joints are carried out through tensile test, hardness measurement and metallurgical investigations.

This paper presents a new numerical model that, unlike most existing ones, can solve the whole liquid sloshing, nonlinear, moving boundary problem with free surface undergoing small to very large deformations without imposing any linearization assumptions.

The time‐dependent, unknown, irregular physical domain is mapped onto a rectangular computational domain. The explicit form of the mapping function is unknown and is determined as part of the solution. Temporal discretization is based on one‐step implicit method. Second‐order, finite‐difference approximations are used for spatial discretizations.

The performance of the algorithm has been verified through convergence tests. Comparison between numerical and experimental results has indicated that the algorithm can accurately predict the sloshing motion of the liquid undergoing large interfacial deformations.

The ability to model liquid sloshing motion under conditions leading to large interfacial deformations utilizing the model presented in this paper improves our ability to understand the problem of sloshing motion in tuned liquid dampers (TLDs), which would eventually help in constructing more effective TLDs.

A systems perspective of waste management allows an integrated approach not only to the five basic functional elements of waste management itself (generation, reduction, collection, recycling, disposal), but to the problems arising at the interfaces with the management of energy, nature conservation, environmental protection, economic factors like unemployment and productivity, etc. This monograph separately describes present practices and the problems to be solved in each of the functional areas of waste management and at the important interfaces. Strategies for more efficient control are then proposed from a systems perspective. Systematic and objective means of solving problems become possible leading to optimal management and a positive contribution to economic development, not least through resource conservation. India is the particular context within which waste generation and management are discussed. In considering waste disposal techniques, special attention is given to sewage and radioactive wastes.