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· Develop an integrated model of product selection and process optimization. · The model is applied to two-stage and three-stage cascade refrigeration systems. · A decomposition-based algorithm is proposed to improve the optimization. · Case study demonstrates the functionality of the model and the algorithm. Designing new refrigerants is a highly advanced field, where it is essential to create efficient refrigerants to meet the growing demand. However, the current approach of relying on experts' experience or existing refrigerant databases may not result in the best refrigerant. In this paper, a refrigerant selection method is proposed that combines the selection of refrigerants with the optimization of the refrigeration process, thus allowing for the selection of the best refrigerant based on the requirements of the refrigeration process for single and cascade system. The paper proposes the combination of properties databases of different refrigerants in the refrigeration process model, enabling both operating conditions and refrigerants to be decision variables. The coefficient of refrigeration performance (COP) serves as the objective function, with 285 compounds as candidate refrigerants. By optimizing this model, both the optimal refrigerant and operating conditions can be obtained simultaneously. However, due to the high complexity of the model, the authors propose an algorithm based on decomposition to efficiently solve the mixed integer nonlinear program, as it provides the best performance. Results demonstrate that the proposed algorithm can achieve the optimization efficiently. Besides, the more complex the problem, the more time it can save. [ABSTRACT FROM AUTHOR]

Improving the accuracy of recommendation systems is a hot research topic, and existing methods have not considered the differences in various types of data. To address this issue, we propose a collaborative filtering recommendation method that combines evaluation relationships and emotional relationships. The emotional relationship is derived from implicit feedback data, and we can exploit the neural network to learn the emotional relationship between users and items. The evaluation relationship is derived from explicit feedback data; similarly, we can exploit the neural network to learn the evaluation relationship between users and items. To obtain emotional and evaluation relationships, we design vector representation and interaction functions based on explicit and implicit feedback data. Moreover, we propose that deep neural networks can be used to integrate evaluation and emotional relationships. To effectively integrate emotional and evaluation relationships, we design multiple data fusion strategies, loss functions, and training strategies. Experimental studies were conducted on five benchmark datasets, and the results show that the collaborative filtering recommendation method based on emotional evaluation relationships can further improve the accuracy of recommendation systems. [ABSTRACT FROM AUTHOR]

Abstract Due to the conflict between economic development and environmental preservation, energy consumption in the construction industry has become an urgent concern. This research aims to measure the interaction between imports and exports in relation to the embodied energy that accompanies international trade from the perspective of vertical specialisation. The energy embodied in the imports and exports of the construction industry is measured and the net embodied energy use is used to identify the level of dependence of the construction industry on international trade. For the construction industries in the selected countries, the share of imported energy embodied in exports is used to show the degree of participation in the global production chain. The construction industries had greater degrees of participation in the international trade of embodied energy from the demand perspective, than from the supply perspective. The findings of this research help to identify the role and position of national construction industries and are beneficial to the design of strategies for the international market. References are also provided to assist policymakers in adjusting natural resource consumption and production structures in the international trade of construction goods and services. Highlights • Over 95% energy embodied in construction products transferred from other sectors. • Shares of imported energy embodied in export measured based on both supply and demand. • Financial crises clearly hurt exports and imports of global construction industries. • International trade of construction products largely driven by demand not supply. [ABSTRACT FROM AUTHOR]

Abstract The construction sector is globally a significant energy consumer and has a particular responsibility to improve its environmental impact as a worldwide sector. Research on energy mitigation in construction has tended to focus on the economic, technological, administrative and community drivers in many countries, but the energy demand trend in the construction sector shows little change in the past and is projected to continue growing under current policies. The aim of this research is to develop alternative insight into this lack of progress from the perspective of globalisation through investigating the energy use embodied in the international trade of construction goods and services. A multi-regional input–output (MRIO) analysis is applied to understand the global consumer countries and their sectors in relation to the energy embodied in the production of their construction goods and services. The energy demands are illustrated by a consumption-based analysis for the worldwide construction sector. The embodied energy of international trade is described at the sectoral level through measuring the sectoral energy export and regional energy import from the sector induced by the final use. Using MRIO tables derived from the World Input–Output Database (WIOD), the results show that there exists great potential for reduction in energy consumption in the construction sector and that a large number of countries increased their dependence on the global construction market over the research period. Highlights • The paper concerns the energy embodied in international trade in the construction sector. • It applies a multi-regional input–output method and a consumption-based approach. • The construction sector has great potential for energy saving in relation to its intermediate input of embodied energy. [ABSTRACT FROM AUTHOR]

Reliable prediction of construction prices is essential for the construction industry because price variation can affect the decisions of construction contractors, property investors, and related financial institutions. Various modeling and prediction techniques for construction prices have been studied, but few researchers have considered the impact of global economic events and the seasonality of construction prices. In this study, global economic events and construction price seasonality as intervention dummies, together with a group of macroeconomic variables, are considered in a vector error correction (VEC) model to accurately predict the movement of construction prices. The proposed prediction model is verified against a series of diagnostic statistical criteria and compared with conventional VEC, multiregression, and Box-Jenkins approaches. Results indicate that the VEC model with dummy variables is more effective and reliable for forecasting construction prices. The VEC model with dummy variables can also assist construction economists to analyze the effect of special events and factors on the construction industry. [ABSTRACT FROM AUTHOR]

• Light-weight piezoresistive sensing materials are prepared by the surface coating sponge with conductive nanoparticles. • The surface coated sponge exhibits high-performance in pressure/strain sensors. • The sensor can detect various human motions. Low-cost production of piezoresistive strain/pressure sensor with high sensitivity, fast response, good stability and repeatability is still one of the critical challenges for the practical applications of flexible piezoresistive materials in human motion detection, health monitoring, wearable electronics, and e-skins. Herein, we develop a simple and efficient route to fabricate the three-dimensional (3D) light-weight piezoresistive sensing materials via the surface coating the polyurethane (PU) sponge with hybrid carbon nanotube (CNT)/carbon black (CB) nanoparticles. It is found that the CNT/CB@PU sponge exhibits high sensitivity, fast response, instant recovery, and stable compression-release signals to the strain/pressure stimuli, which can be designed into the versatile piezoresistive sensors to detect various human motions within a wide strain range, such as blowing, swallow, deep breath, finger bending, elbow bending, and knee bending. More importantly, this work illuminates the sensing mechanisms of conductive sponges coated with different dimensional nanoparticles and paves a new way toward large-scale and low-cost production of wearable pressure/strain sensors. [ABSTRACT FROM AUTHOR]

The uncontrolled socioeconomic development through substantial consumptions and transfers of materials, energy and other natural resources plays a significant effect on the deterioration of the ecological environment. How to quantify these consumptions and transfers has been a difficult issue and attracted many researchers from various disciplines. The purpose of this research aims to reveal the ecological utility of the Australian economic sectors based on embodied energy. The research commences with the development of embodied energy input–output tables of Australia and then adopts the ecological network analysis (ENA) principles combined with the hypothetical extraction method (HEM) to investigate the interaction of sectoral embodied energy the economic system. A utility value matrix is used to determine the ecological relationship from one sector to another, the degree of mutualism of the entire economic system and its synergism, and the importance of a sector in the economic system. The ecological relationships of all pairs of economic sectors revealed from this research can be used to describe the Australian economic system from the perspective of embodied energy. The long-term development interests of various industries in Australia can be balanced and adjusted according to the positive and negative ecological relationship. The influence of the specific structure on the industry is measured by the connectivity and diversity of the energy network. [ABSTRACT FROM AUTHOR]

• Effects of energy embodied in exports of the construction sector on energy poverty from a perspective of vertical trade. • The influence of the trade pattern of vertical specialisation on energy flow for the phenomenon of energy poverty in 40 countries. • Energy poverty measured by the energy embodied in vertical specialisation trade from the aspect of value added in the construction sector. Energy requirements have expanded significantly in the process of global development while the energy crisis as an issue is becoming a limitation for economic development and environmental sustainability. The construction sector has contributed to the total energy consumption at a national and global level. The quality of human life is still impacted by energy and fuel poverty. This paper aims to examine the effects of energy embodied in intermediate and final goods of the construction sector on energy poverty from a perspective of vertical trade. The modified Energy Development Index (EDI) in the construction sector is applied to measure the extent of energy poverty in a country. Based on the World Input-Output Database (WIOD), the energy embodied in the exports of vertical trade has been measured in the construction sector. The results show that the developing trend in 40 countries increased in different increments in the research period. Comparing the results at the beginning and the end of the research period, the modified EDIs measured by energy embodied in exports of vertical trade increased in 19 countries but decreased in 21 countries. The positive implications for reducing energy/fuel poverty is proposed in policy making and strategic management in foreign trade within the construction sector. [ABSTRACT FROM AUTHOR]

International trade supplies a great number of new opportunities for the development of the construction industry in relation to globalisation. Many construction industry studies relevant to international trade have focused on the evaluation of national trade performance in energy from the viewpoint of the whole economy or of a specific product. Intermediate demand and input, as significant components of the input–output table, indicate the interrelationships between economic sectors, as well as the economic structure in relation to aspects of production and consumption. The purpose of this paper is to analyse the international trade in construction products and services with a focus on their embodied energy consumed at the intermediate level. A multi-regional input–output method is adopted to assess the transfer of embodied energy that accompanies the international trade of the global construction industries. The net embodied energy in the construction industry of each world region has been identified based on its exports and imports. The results indicate that the average embodied energy consumption in intermediate demand over 1999–2009 accounted for approximately 90% in the world construction industries. International construction industries were dominated by activities of intermediate production which aimed to satisfy the embodied energy consumption in the intermediate and final requirements. The USA, China, Japan, Spain and India were the top five in the scale of the intermediate consumption of embodied energy. The production of intermediate goods and services in some world regions decreased its dependence on embodied energy imports from the international construction industries. This study highlights the influence of the international trade in embodied energy on the development of the construction industry at the intermediate level. The outcomes provide considerable resources and references for policy adjustment and strategy design in the management of international trade for the construction sector. [ABSTRACT FROM AUTHOR]

Green building assessment methods, which play an essential role in promoting the development of green buildings, have attracted much attention in recent years. Many studies have been conducted on the development of new assessment methods and improvement of existing ones through comparative analysis. However, there is no comprehensive study that explicitly explores these efforts. For this purpose, a systematic review of the existing literature on green building assessment methods through comparative analysis is carried out in this paper. The main contributing authors as well as represented countries and areas are investigated. The comparison rules, including the number of comparative assessment methods and high frequency assessment methods, as well as the current status of comparison topics are explored. Finally, some research opportunities are proposed for future development. The research results would serve as a useful reference for both industry practitioners and academics who are interested in the development of green building assessment methods. [ABSTRACT FROM AUTHOR]

Sustainable development of the construction industry requires balancing economic growth and resulting environmental impacts. The aggregate embodied CO 2 intensity (CI), defined as the ratio of embodied CO 2 emissions per embodied value added, has been studied in previous research to evaluate the environment performance and mitigation policies from a final demand perspective. However, there is a relative lack of studies analysing CI from the perspective of border-crossing frequency (BCF), the number of national border crossings of traded products. This paper first analyses the CI in import products of the construction industry at each BCF under a multi-regional input–output framework and decomposes the change in CI in import products into the value-added distribution factor and the efficiency factor under conditions of BCF. The results indicate that CIs in import products of construction industries experienced declines from 2000 to 2014. The value-added distribution factor appeared to have an inhibitory effect only at the first BCF on the growth in CIs in import products of construction industries and prompted growth in CIs in import products at higher-order BCFs. The efficiency factor had a significant promoting effect on the decline in CIs in import products of construction industries but this promotion effect became weaker with an increase in the level of BCF. The reduction effect of the value-added distribution factor on the changes in CIs in import products of construction industries was smaller than that of the efficiency factor, indicating that the decrease in the CI was largely determined by the improvement in environmental efficiency at each BCF. Driving force analysis of the change in CI in import products of the construction industry from the perspective of BCF can effectively help in adjusting the import structure in order to control the growth of CI in import products. [ABSTRACT FROM AUTHOR]

Conductive polymer composites (CPCs) based flexible temperature sensors are highly desirable for electronic skins (e-skins) due to their flexibility, good processability, and lightweight. However, it is still a challenge to fabricate a flexible CPC-based temperature sensor with linear negative temperature coefficient (NTC) effect because CPCs normally exhibit non-monotonic dependence on temperature. Herein, we prepare the flexible thermoplastic polyurethane (TPU)/single-walled carbon nanotubes (SWCNTs) composites by the facile method of solution blending and thermal annealing. The as-prepared composites exhibit a monotonic and linear NTC effect in the temperature range of 30–100 °C, which can be designed into highly flexible and sensitive temperature sensors. The as-prepared sensor can achieve respiratory monitoring, cellphone charging time monitoring and non-contact temperature detection, attributing to its high accuracy (0.1 °C), excellent reproducibility and high reliability (Deformation and heating rate have no effect on the thermal response.). Moreover, the sensors also show resistance response to infrared radiation owing to the excellent photo-thermal effect of SWCNTs. The integrated linear NTC effect and photo-thermal effect endow the sensors with tremendous potentials in e-skins and wearable electronics. The TPU/SWCNTs composite-based temperature sensors with linear negative temperature coefficient effect and photo-thermal effect, which have tremendous potential in personal healthcare monitoring and e-skins. [Display omitted] • A composite with linear NTC effect and photo-thermal effect was achieved. • The composite exhibits excellent thermosensation with high accuracy, reproducibility and reliability. • The composite shows resistance response to infrared radiation. • The composite can achieve respiratory monitoring, cellphone charging time monitoring and non-contact temperature detection. • The composite has tremendous potential in temperature sensors, e-skins and personal healthcare monitoring. [ABSTRACT FROM AUTHOR]

The issue of sustainable energy consumption in the socio-economic system has been widely investigated in recent studies. Embodied energy transfer is also part of the normal economic pattern. To evaluate the sustainability of a system, it is important to consider not only the growth of the system as an indicator, but also the development of the system's structure. Growth and development are two phenomena that need to be quantitively measured because these phenomena closely reflect sustainability. However, little research has studied the effects of sectoral level on growth and development. This research addresses growth and development from a network perspective in order to assess the sectoral effects on system characteristics by using information-based ecological network analysis (IENA) and a hypothetical embodied energy network model. In this study, taking the Australian industrial system as an example, Australian national input–output data and industrial consumption data are used to establish the embodied energy network based on Australian industries. The research constructs an embodied energy cycle network with seven major industries and uses a hypothetical extraction method to establish a hypothesis network for each sector. Then the research compares the hypothetical networks with the original embodied energy network. The differences represent the sectoral effects on the growth and development of the embodied energy network. By using the IENA method with the hypothetical network model, the contribution of a single specific sector can be quantified. Analytical results reveal that the sectoral increases in the volume of the network do not reflect system sustainability, while system sustainability improvement requires sectoral contributions not only to system volume but also to an increase in network organization. The research develops a sectoral-level model to identify the key drivers in the identified system from the network perspective. The results show the sectors with high levels of self-embodied energy flows make high contributions to the improvement of system sustainability in the Australian embodied energy network. [ABSTRACT FROM AUTHOR]

Value-added trade has increased rapidly in recent decades in the context of globalisation. This paper aims to measure the energy embodied in the value-added trade and the ecological relationships in the networks of the international construction industries. A hybrid method which combines ecological network analysis and the input–output method has been adopted. The direct energy intensities in most countries ranged from 0 to 3.0 trillion joules per million US$ and the dominant relationships were control and exploitation in the selected 15 years. For the construction sector, the negative relationships were dominant at 63.9% in Australia and 79.19% in China. The ratio of positive relationships increased from 24.3% to 31.5%, while the ratio of negative relationships declined from 75.7% to 68.5% over the 15 years. The mutualism index ranged from 0.72 to 0.98 over the 15 years, maintaining a value less than 1. In contrast, the synergism index had an increase of 12.2 over the 15 years. The results indicate that both direct energy intensity and the value-added ratio are important factors in relation to the energy embodied in value-added trade. Sectoral influence on the national industrial system has been interpreted in this paper to stimulate further research. • The energy embodied in the value-added trade of the international construction industries. • The combination of ecological and economic connections in an analysis of value-added trade. • The influence of specific construction sectors on the network depending on flow capacity. • The exploitation and control relationships that dominate the value-added trade system. • The balance between the value-added ratio and energy intensity in sustainable development. [ABSTRACT FROM AUTHOR]

An increasing utilization of flexible and wearable electronics in human motion monitoring, healthcare monitoring and electronic skin urges the rapid development of flexible strain sensors. However, it is still a challenge to fabricate flexible strain sensors with both ultralow detection limit and wide sensing range. Herein, we develop a universal strategy to design the flexible strain sensor with both ultralow detection limit and wide sensing range based on the dual sensing layers with multiple sensing mechanisms, which can combine the advantages of sensing mechanisms of tunneling effect and crack propagation. Attributed to the multiple sensing mechanisms, the designed strain sensor possesses an ultralow detection limit of 0.01% and a wide sensing range (The maximum sensing strain is greater than 100%, high enough for all human motion monitoring). Moreover, excellent stretchability, fast response (68 m s)/recovery (68 m s), and outstanding reproducibility are achieved by this dual-sensing-layer sensor. Because of these outstanding performances, this strain sensor is capable of detecting and distinguishing both subtle physiological movements (e.g. pulse, coughing, and swallowing) and large-scale human motions (e.g. walking, leg lifting, and squatting), indicating great potential applications in wearable electronics. This work proposes a new strategy, i.e. constructing multilayer sensing structure with multiple response mechanisms, which may overcome the long-standing challenge of high-performance flexible strain sensor. [Display omitted] [ABSTRACT FROM AUTHOR]

Energy sustainability has great importance in the development of the economy and society since energy is a necessary driving force for economic growth. The construction sector accounts for a greater percentage of global energy consumption than most other sectors. The structure of exports in the current trade pattern has affected the transmission of sectoral embodied energy through changes in regional economies. This paper uncovers the composition of productions for gross exports and examines embodied energy from the viewpoint of value added through a case study in the construction sector. Multi-regional input–output tables have been used to process the data relevant to economic trade and energy input, while the production of gross exports in 40 countries has been decomposed into the exports of value-added trade and the exports of vertical specialisation trade based on data from world input–output tables. The decomposition and reorganisation clearly show the pathways and composition in the trade activities of gross exports. The embodied energy of value-added exports accounted for 60–90% of gross exports in the construction sectors of 37 countries. The framework for sharing production in the construction sector still dominated the connections among many countries, especially the trade relationships between large economies. In the process of vertical specialisation trade, the foreign value added of the construction sector was still limited by significant events such as the global financial crisis. The construction sectors were ranked between 5 and 11 in all 35 domestic sectors in 34 countries as measured by the total export of embodied energy. So, the creation of high value added is enhanced by improvement in energy efficiency in the construction sector. However, the reduction of energy consumption in the construction sector may indirectly increase energy consumption in its upstream sectors because of the connection between exports and related production. The balance between energy consumption and creation of value added in exports is an important consideration for government supervision and sectoral development. Local construction markets need to strengthen their ability in the supply of intermediate goods, which benefits value-added exports and domestic demand. Moreover, developing national and international supply chains can positively offset the impact of the imbalanced distribution of globalised production. • Decomposition reveals the pathways of energy flows embodied in vertical specialisation and value-added trade. • The development of technology-intensive products is encouraged in countries with high embodied energy intensity. • The creation of value added is mainly driven by the direct requirements in export trade. • The construction sector is located in high positions in 35 domestic sectors when measured by the exports of embodied energy. [ABSTRACT FROM AUTHOR]

Energy is a vital necessity in driving the development of the global economy, national industries, and even services for people. The construction sector consumes a high proportion of energy and this requires improvement for its sustainable development. Due to the growth of multilateral trade, the energy flows embodied in the global trade network have become more complex, and the energy embodied in the exports of vertical specialisation trade has increased rapidly in satisfying domestic final energy consumption. This paper traces the original creation of the value added in the national construction sectors in the global value chain based on their energy consumption in the production of gross exports. The gross exports are broken down into domestic and foreign value-added exports, and the energies embodied in these two types of exports are analysed and compared. The exports of foreign value added is mainly indicated by the exports of vertical specialisation trade. Net outflows in domestic value-added exports and net outflows in exports of vertical specialisation trade are then used in measurement of sectoral position in the global value chain. The results show that the overall trend of domestic value-added exports continues to increase in the construction sectors of the majority of countries. Russia, China, and the USA performed significantly in relation to the quantity of energy embodied in domestic value-added exports. Moreover, the effect of technology needs to be considered in the production of exports for vertical specialisation trade. The distribution of the net outflow is similar to the performance of the energy embodied in domestic content in the construction sector. The net inflow of embodied energy was positive in all countries, which indicates that the energy embodied in exports of vertical specialisation trade was mainly derived from the support of the international market. Only one country had a lower net outflow of embodied energy than in gross exports. For policymakers, a policy guiding the exports of the construction sector needs to be considered in relation to the origins of the value added. The export structure in the construction sector is encouraged to move toward technology-intensive, instead of labour-intensive products in order to enhance sustainable energy development. • Energies embodied in domestic value-added exports in the construction sector • Energies embodied in vertical specialisation trade in the construction sector • Identifying the origins of value-added creation and its assimilation by destinations • Inflow and outflow of embodied energies in gross exports of the construction sector • Positioning construction sectors in the global value chain by energy transmission [ABSTRACT FROM AUTHOR]