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Purpose: Prefabricated construction is an innovative technique for decreasing carbon emissions in the construction industry. However, as the investors of housing projects, a majority of developers are unwilling to adopt prefabricated housing in practice. To promote prefabricated housing, this study aims to develop an integrated framework of fuzzy-decision making trial and evaluation laboratory (fuzzy-DEMATEL) and system dynamics (SD) to understand the underlying influencing mechanism of developers' willingness. Design/methodology/approach: Through literature review, a total of 17 influencing factors were identified. Then, the interrelationships among the factors were evaluated by 10 experienced professionals, and the impacts given and received by each factor were further analyzed through fuzzy-DEMATEL. Based on the technology acceptance model (TAM), a SD model was developed to explore the influencing mechanism. Findings: The major cause factors were identified, including mandatory implementation policies, economic incentive policies, environmental protection policies, component standardization and developers' economic strength. This group of factors was expected to be given priority attention in the case of limited resources. On the other hand, the results indicated that economic incentive policies and mandatory implementation policies could affect the developers' willingness via perceived usefulness, while the others mainly influenced perceived ease of use. Originality/value: Little research has focused on the interrelationships among the influencing factors of developers' willingness to adopt prefabricated housing. This study contributed to understanding the mechanism of developers' willingness from a systematic view and providing the priority of influencing factors. Several strategies were proposed to improve the practical implementation of prefabricated housing development. [ABSTRACT FROM AUTHOR]

The recent expansion of shellfish mariculture could significantly impact the ocean carbon cycle and its associated biogeochemical processes. To understand the source and fate of particulate organic carbon (POC), a summer cruise was conducted from September 8 to 10, 2022, at a mussel farm on Gouqi Island and its adjacent areas located in the East China Sea. Parameters included in situ temperature and salinity, contents of dissolved oxygen (DO), suspended particulate matter (SPM), POC, and chlorophyll a (Chl a), as well as the stable carbon isotopic composition (δ13C) of organic matter in particle and sediment samples, which were analyzed to facilitate a comparative assessment of the areas inside and outside the mussel farm. The POM was much fresher (POC/Chl a < 150) inside the farm with little impact from sediment resuspension (lower SPM content, 11.6 ± 6.6 mg/L), while a significant influence of sediment resuspension was found outside the farm (SPM > 20 mg/L, POC/Chl a > 150). A two end-member mixing model showed that 82.0 ± 6.0% of POC originated from marine algae within the farm, much higher than that outside the farming area (66.1 ± 7.8%). Moreover, elevated DO saturation but relatively low Chl a concentration within the farm suggested continuous algae consumption following potential high productivity. The averaged δ13C values were similar among suspended POC, sinking POC, and sedimentary organic carbon within the farm, implying the fast export and burial of POC. This is likely due to the filter-feeding habits of mussels, who ingest fresh POC and then pack it as fecal pellets that rapidly settle into the sediment. This study sheds light on the distribution and sources of POM inside and outside the mussel farm on Gouqi Island, enhancing our understanding of the marine carbon cycle on shellfish farms and providing insights into the underlying biogeochemical processes. [ABSTRACT FROM AUTHOR]

With the advancement of China's construction industry and the rapid pace of urbanization, there has been heightened concern about and demand for improved construction environments. Rail transit projects commonly experience noise levels that exceed standard limits, resulting in a significant challenge posed by construction noise pollution. This issue not only disrupts the normal operations of construction sites but also profoundly impacts the mental well-being, auditory health, and nervous system of both construction workers and nearby residents. Consequently, effectively addressing construction noise pollution has emerged as a pressing issue. This study systematically reviewed domestic and international construction noise standards, integrating field research and noise monitoring data from construction sites. It provided a detailed analysis of the sources and hazards of construction noise and explored the source and propagation characteristics of construction noise from rail transit projects. The feasibility of controlling construction noise from various perspectives was investigated. Finally, the study analyzed the causes of construction noise exceeding standard limits, proposed layout strategies and control methods tailored to the stages of construction, and offered comprehensive noise control recommendations, culminating in a complete control process. This study fills a gap in research related to construction noise for rail transit projects, provides a valuable foundation for developing construction noise control objectives, and offers practical guidance on the implementation of measurement and control methods. These insights will help advance the field of construction noise control and management, and provide valuable insights for similar domestic rail transit projects. [ABSTRACT FROM AUTHOR]

Noise pollution is considered an important aspect of global environmental issues. The construction of urban rail transit is gradually increasing, leading to excessive noise pollution in rail transit projects. The noise during construction has negatively impacted both the construction workers and residents in the surrounding neighborhoods. Therefore, monitoring and managing the noise is very important. In this study, noise sensors and sound level meters were employed to monitor the noises produced in an urban rail transit project. Then, Cadna/A software was utilized to simulate the noise characteristics. Based on the results, it was found that daytime noise has a maximum of 89.5dB(A), which exceeds the standard. To alleviate the noise impacts, a noise reduction scheme was put forward. The implementation of the noise reduction scheme is predicted to have an effect, resulting in an approximate 10-20dB reduction in noise level. The implementation of the scheme will allow the construction noise of the case projects to meet the national standard. This study addresses the research gaps related to construction noise in urban rail transit projects and provides valuable references for the noise control of urban rail transit projects in China. [ABSTRACT FROM AUTHOR]

Rail transit is an important part of the urban transportation system, while the noise generated during construction seriously affects the engineering personnel and surrounding residents. To investigate the noise emissions and characteristics during the construction of the enclosure structures in the rail transit engineering project, an empirical study is conducted through on-site surveys, semi-structured interviews, and experimental monitoring. The results indicate that during enclosure structure construction, there are nine key noise-emitting machines and four key noise-generating construction processes. Among them, the equivalent average sound levels of six machines, including pneumatic hammers, pneumatic drills, concrete pump trucks, construction drills, rotary drilling rigs, and grooving machines, exceed 80 dB(A). The energy contribution rate curves of machine spectra peak at 63 Hz, 500 Hz, 1000 Hz, and 4000 Hz, which have certain effects on construction personnel and nearby residents. Meanwhile, guide wall construction, groove construction, reinforcement cage fabrication and hoisting, and concrete pouring are identified as key noise-generating construction processes. This empirical investigation helps to establish a theoretical basis for noise control during the construction of enclosure structures in urban rail transit engineering projects, and the results provide valuable references for the formulation of auxiliary noise reduction measures. [ABSTRACT FROM AUTHOR]

With the acceleration of urbanization in recent years, China has witnessed large-scale construction across its provinces, generating massive amounts of construction waste that pose challenges to environmental protection and sustainable development. This study evaluated the impact of construction waste policy intensity on its environmental efficiency. Firstly, the content analysis method was used to analyze the construction waste policy text quantitatively. Second, this study constructed a slack-based measure (SBM) model based on data envelopment analysis (DEA), considering resource input and construction waste output to measure environmental efficiency. Finally, we built and tested an econometric model of how policies affect environmental efficiency using the system generalized method of moments (SYS-GMM). The findings indicate a non-linear U-shaped link between policy intensity and environmental efficiency. Among all five control variables, population density, urbanization level, and technological innovation enhance environmental efficiency, while economic development and highway density will lower it. This study advances the research on construction waste policies and offers some insights for the construction industry to pursue sustainable development. [ABSTRACT FROM AUTHOR]

In China, the annual generation of construction and demolition waste (CDW) has been steadily increasing, accompanied by a generally low recycling rate. To promote sustainable development, there is an urgent need to enhance the recycling of CDW. This paper aims to investigate the determinants of construction stakeholders' intention to use CDW recycling products in China. The stimulus–organism–response (S-O-R) model, integrating the technological–organizational–environmental (TOE) framework, personal perceptions, personal traits, and the intention to use, was chosen as our theoretical model. Through an analysis of 272 valid questionnaires, the partial least squares structural equation modeling (PLS-SEM) was utilized to evaluate the model and test the proposed hypotheses. The results indicated that personal traits are the most influential factor shaping construction stakeholders' intention to use, followed by personal perceptions, while external stimuli exert no direct significant impact on the intention to use. Nevertheless, personal traits and personal perceptions play a significant mediating role in the relationship between external stimuli and the intention to use, forming a noteworthy serial chain mediation. The research findings imply that in China, bolstering personal traits plays a critical role in guiding and promoting the intention to use CDW recycling products. [ABSTRACT FROM AUTHOR]

China officially entered the aging society in 2000, witnessing a rapid surge in demand for senior care services. In response, the real estate industry introduced the concept of Continuing Care Retirement Communities (CCRCs). The relationship between this model and complex risks in urban security resilience encompasses various factors, including filial care, demand for senior care, and urban sustainable development. The strategic layout and planning of CCRC enhance the security resilience of urban operational systems in the face of intricate senior care risks. However, the development and operation of CCRCs have encountered the challenge of sluggish project progress, primarily due to a lack of robust purchase intention. This study investigates the factors influencing the purchase intention of CCRCs in mainland China, using the Theory of Planned Behavior (TPB) as the foundational theoretical model. Additionally, three contextual constructs (economic cost, product performance, and external stimuli) were introduced to form the initial model. Based on the initial model, six factors were identified and nine hypotheses were proposed. A questionnaire survey was conducted to collect data, and Structural Equation Modeling (SEM) analysis was employed to test the proposed hypotheses. The results indicate that consumers' purchase intention of CCRCs is primarily influenced by product performance and subjective norms, followed by economic cost. At the same time, external stimuli have a significant indirect effect on it. [ABSTRACT FROM AUTHOR]

Time-series samples intercepted via three synchronized moored sediment traps, deployed at 1000 m, 2150 m, and 3200 m in the northern South China Sea (NSCS) during June 2009–May 2010, were analyzed to quantify the bioactive trace metal fluxes in sinking particles and investigate their different source contributions. Iron (Fe) primarily originated from lithogenic sources. Manganese (Mn), cobalt (Co), nickel (Ni), copper (Cu), and zinc (Zn) exhibited various degrees of enrichment over their continental crustal ratios. Since the sources of bioactive trace metals in sinking particles can be divided into lithogenic, biogenic, and excess fractions, mass conservation calculations were used to quantify the contribution of each source. The results showed that Fe, Mn, and Co had extremely low biogenic proportions (0.1–3.3%), while Ni, Cu, and Zn had higher proportions (2.7–17.3%), with the biogenic fraction decreasing with the depth. Moreover, excess sources accounted for a significant proportion of Mn (68–75%), Co (34–54%), Ni (60–62%), Cu (59–74%), and Zn (56–65%) in sinking particles at the three sampling depths. The excess fractions of Mn, Co, and Cu in sinking particles can be affected by authigenic particles. This is supported by their similar scavenging-type behavior, as observed via the increase in their fluxes and enrichment patterns with the increasing depth. Furthermore, the excess fractions of Ni, Cu, and Zn may have significant contributions from anthropogenic sources. The variability of Fe in sinking particles was mainly controlled via lithogenic matter. Notably, organic matter and opal were found to be pivotal carriers in the export of excess bioactive trace metals (Mn, Co, Ni, and Cu) via the water column, accompanied with the elevated ballast effect of lithogenic matter with the depth. However, the transportation of excess Zn was more complicated due to the intricate processes involved in Zn dynamics. These findings contribute to our understanding of the sources and transport mechanisms of bioactive trace metals in the marine environment. [ABSTRACT FROM AUTHOR]

At present, the scale of subway construction in Chinese cities has reached a new height, and the shield slag produced by it has also surged year by year. Untreated subway shield slag not only occupies the space resources of the country, but also carries CO2, which causes negative impacts on the environment and which, as a result, is not conducive to the realization of the goal of the national "double-carbon" strategy. Therefore, how to effectively manage the shield slag produced by subway construction has become a scientific problem that needs to be solved urgently. In order to scientifically dispose of metro shield slag and quantify the carbon reduction intensity of its disposal, based on the new shield slag integrated recycling technology, and taking a tunnel interval of Shenzhen Line 13 as an example, this study systematically sorted out the shield slag disposal process, clarified the management path of the on-site resource utilization of slag, and quantitatively compared the carbon emissions before and after the treatment as well as carbon reduction intensity. The results show that the on-site disposal process is basically feasible, and that, it is possible to achieve a shield structure slag reduction of resource products and mud cake water content of less than 40% of the target, in the case of 160,000 m3 of shield structure slag resource utilization after a total carbon reduction of about 4240.13 t CO2, of which each preparation of 1 m3 of recycled bricks can bring about a benefit of carbon reduction of 240.09 kg CO2. Compared with the conventional mud head truck slag disposal, shield structure slag resource utilization can save a utilization cost of about 10.4 million yuan, meaning that, in terms of economic and social levels, this method can achieve good benefits. This case verifies the feasibility of the new technology, and the results of the study can provide experience for other metro projects' shield slag resource utilization, and provide stakeholders with a shield slag recycling management strategy for government departments to scientifically formulate metro shield slag management policy to provide data support. [ABSTRACT FROM AUTHOR]

The proportion of highways in infrastructure investment is growing and playing a significant role. It has many advantages in all aspects of social life and has become a timely subject of recent research. However, the existing literature lacks a systematic review of the current research status of highway investment. Thus, this study aims to conduct a scientometric analysis of the existing literature on highway investment to provide an overview of its current state of research. Using the Web of Science Core Collection database, this study conducted searches and screenings of 614 documents related to highway investment from 2013 to 2023. Subsequently, VOSviewer software was employed to perform a visual analysis of source journals, authors, countries/regions, article citations, and keywords. The results reveal that Transportation Research Record is identified as the most influential journal in the field of highway investment. Bullock, Darcy M. has published the greatest number of articles. In addition, the United States has published the largest number of studies and contributed significantly to the advancement of highway investment. Benjamin Faber has received the highest number of citations and normalized citations. Through co-occurring keywords analysis, keywords such as "risk", "influence", "investment decision", and "infrastructure investment" receive more attention. The findings of this research can contribute to providing researchers and scholars with a more comprehensive understanding of the current research status of highway investment and its key issues. [ABSTRACT FROM AUTHOR]

The rapid urban renewal progress has generated a large amount of construction and demolition (C&D) waste in China. According to the concept of circular economy (CE), producing products with recycled content (PwRC) is an effective solution to achieve sustainable C&D waste management. However, the low market acceptance of PwRC affects stakeholders' purchase intention, which hinders the development of the PwRC industry. In order to clarify the stakeholders' purchase intention and investigate the influencing mechanism of stakeholders' purchase intention, a novel method which combines structural equation modeling (SEM) with a back-propagation neural network (BPNN) is proposed. The method makes full use of the causal analysis ability of SEM and the nonlinear characteristics of BPNN to simulate and to verify the path of product cues, perceived value, and behavioral intention of stakeholders. The results reveal that the brand and materials of PwRC can affect stakeholders' perceived value, and in turn, affect their purchase intention. Focus on the brand and materials of PwRC will help recycled product manufacturers and governments to promote stakeholders' purchase intention and the development of the C&D waste recycled products market. [ABSTRACT FROM AUTHOR]

A majority of metro projects have been constructed to reduce urban traffic congestion and to improve the convenience of public transportation, but these projects also produced a significant amount of engineering slag and mud. The shield construction method could improve the efficiency and safety; this technique has been frequently used in tunnel excavation projects. However, the spoil produced during the shield construction is challenging to deal with. In literature, though there has been an increasing number of studies on the technologies of utilizing shield spoil, the on-site utilization of shield spoil is still a subject of little research. This study introduced an implementation framework for the on-site utilization of shield spoil based on successful case experiences. It aims to assist project managers in efficiently implementing on-site resource utilization projects and to address the gaps in the relevant field. A case study was conducted in the Shenzhen Metro Line 13 North Extension Project; this study collected data through six semi-structured interviews and field research, analyzed the data, and constructed a framework using thematic analysis and focus group discussions. The three components of the implementation framework are project planning, project construction, and project closing, and each section describes what must be accomplished during that phase. Additionally, three recommendations—(1) combining intelligent technology to optimize the existing equipment, (2) utilizing lean technology in project execution, (3) establishing strategic partnerships with construction waste recycling enterprises—are also made for the development of the shield spoil utilization project. This study uses the Shenzhen Metro Line 13 North Extension Project as a model to theoretically underpin future research on shielding spoil on-site during resource utilization projects and to achieve the repeatable promotion of shield spoil utilization technology in Shenzhen. [ABSTRACT FROM AUTHOR]

Ground-penetrating radar (GPR) is an effective geophysical electromagnetic method for underground target detection. However, the target response is usually overwhelmed by strong clutter, thus damaging the detection performance. To account for the nonparallel case of the antennas and the ground surface, a novel GPR clutter-removal method based on weighted nuclear norm minimization (WNNM) is proposed, which decomposes the B-scan image into a low-rank clutter matrix and a sparse target matrix by using a non-convex weighted nuclear norm and assigning different weights to different singular values. The WNNM method's performance is evaluated using both numerical simulations and experiments with real GPR systems. Comparative analysis with the commonly used state-of-the-art clutter removal methods is also conducted in terms of the peak signal-to-noise ratio (PSNR) and the improvement factor (IF). The visualization and quantitative results demonstrate that the proposed method outperforms the others in the nonparallel case. Moreover, it is about five times faster than the RPCA, which is beneficial for practical applications. [ABSTRACT FROM AUTHOR]

It is recognized that design for excellence (DfX) methods could deliver significant performance improvements in industrialized construction (IC) projects. However, DfX methods in IC projects in China have been stifled, and existing solutions have failed to deliver expected outcomes. This study investigated the significance of thirty-one challenges of implementing DfX methods in IC projects in China using a questionnaire survey of domain practitioners and academics. Statistical analysis showed that all the challenges were perceived as significant. The top five significant challenges are linked to limited systematic rules, required additional commitment, code compliance complexities, higher design costs, and requirements for continuous design performance evaluation. The study established four principal constraints: limited knowledge and organizational readiness, unsupportive entrenched industry practices, increased organizational financial burden, and deficits in bespoke technical requirements. Therefore, the study offers a fresh insight into the challenges of implementing DfX methods in IC projects in China. It provides supporting evidence for developing countermeasures to improve the wider implementation of DfX in IC projects. The investigated challenges contribute to the theoretical checklist of constraints to implementing DfX methods in IC projects and may form a useful basis for future research. [ABSTRACT FROM AUTHOR]

Introduction: We investigated the role of macrophage migration inhibitory factor (MIF) on dendritic cells (DC) during acetaminophen (APAP)‐induced acute liver injury (ALI) in mice. Methods: First, we randomly divided the mice into experimental (ALI model) and control groups, then intraperitoneally injected 600 mg/kg of APAP or phosphate‐buffered saline, respectively. Then, we collected liver tissue and serum samples to evaluate liver inflammation using serum alanine aminotransferase level and hematoxylin and eosin (H&E) staining of liver tissues. Flow cytometry was used to identify changes in the quantity and percentage of DCs, as well as the expression of cluster of differentiation (CD) 74 and other apoptosis‐related markers in the liver. Next, we randomly divided the mice into APAP‐vehicles, APAP‐bone marrow‐derived dendritic cells (BMDCs), APAP‐MIF, APAP‐IgG (isotype immunoglobin G antibody) groups (four mice per group), after APAP injection, we injected control extracts, BMDCs, mouse recombinant MIF antibodies, or IgG antibodies into the tail vein. Lastly, the severity of the liver injury and the number of DCs were assessed. Results: The APAP‐induced ALI mice had increased hepatic MIF expression but significantly lower amounts of hepatic DCs and apoptotic DCs than healthy mice; CD74 expression on the HDCs also increased markedly. Supplementing APAP‐induced ALI mice with BMDCs or MIF antibodies significantly increased the number of hepatic DCs compared with the control mice, alleviating liver damage. Conclusion: The MIF/CD74 signaling pathway may mediate hepatic DC apoptosis and promote liver damage. [ABSTRACT FROM AUTHOR]

Green building (GB) policies are continuously being launched and adjusted in China to pursue resource conservation and emission reduction. Though reviewing the policy evolution could reveal the industry's historical experience and strategic development concept and contribute to assessing and enhancing the policy system's effectiveness, a comprehensive review of the whole GB policy system is still lacking in China. Consequently, this study examined the evolution of 1083 GB policies in China over the past two decades from the perspectives of policy objectives, policy content, and policy tools through text mining and content analysis, filling the research gap. Results show that GB policy objectives were gradually being quantified and formulated in greater detail, with the foci changed from innovation award and assessment to energy-saving retrofit and prefabrication. Supervision policies were primarily used among seven policy tool categories in recent years. The policy enhancement recommendations were proposed accordingly, supporting policymakers to improve the policy settings, providing real-time orientations for industrial sustainability development, and enlightening other countries to promote GBs. [ABSTRACT FROM AUTHOR]

Strengthening the resource utilization of construction waste can improve the environment, alleviate resource shortage, and build a harmonious ecological environment between man and nature. Prospect theory was integrated into trilateral evolutionary game theory to analyze the processes of resource utilization of construction waste among local government, construction enterprises, and the public by establishing the perceived payoff matrix of the three players in the game and using the replication dynamic equation to analyze their strategy choices and evolution path. The results showed that the strategies of the three players depended on the strategies chosen by the other side, the perceived value of the relevant parameters, and the numerical relations among them. Under the conditions that the local government reasonably controlled the supervision cost and the degree of rewards and punishments, the construction enterprise promoted the resource-based technology and management means, and the public enhanced the sense of social responsibility, the game model would evolve toward the ideal state of (1,1,1), to realize the resource utilization of construction waste. [ABSTRACT FROM AUTHOR]

Sewerage systems-related solid waste accumulates in considerable quantities in urban water systems, including rainwater drainage pipes, pumping stations, grease traps, grit chambers, and septic tanks. Traditional management methods, such as sanitary landfilling, incineration, and composting, not only endanger the environment but also consume a significant amount of land. To address this problem, a variety of waste was collected from a terminal and different facilities in sewerage systems, and the characteristics of solid waste were tested and analyzed. The corresponding appropriate approaches to resource recovery strategies were proposed in detail. The solid waste in the wastewater treatment plant (WWTP) contains low organic matter content and a certain quantity of heavy metals, making recycling difficult. Before the solid waste enters the WWTP, the strategy of pre-sorting, treating, and recycling the solid waste is worth recommending. The waste was divided into three categories based on its nature, and corresponding resource utilization strategies were proposed. A small part of solid waste that is not suitable for pre-recycling can be discharged normally and enter the WWTP for treatment. This paper provides a scientific basis for the green resource utilization of solid waste in the field of sewerage systems in developing countries. [ABSTRACT FROM AUTHOR]

China's construction industry is an important driving force for the development of society. Nevertheless, with the recent new normal of economic development, traditional construction approaches cannot meet the requirements of socialist modernization and sustainable construction. As such, the development of the construction industry needs to match the recent developmental concept of green environmental protection. Therefore, China's construction industry needs to explore innovative development paths of transformation and upgrading. Recently, the Chinese government has been vigorously promoting building information modeling (BIM) applications. However, in the real-world construction process, BIM applications have not achieved their expected impacts. To satisfy the practical demands, this research uses the social network analysis method to analyze the key hindering factors in order to clarify the significance and influencing mechanism of each factor. The current study identified 12 key hindering factors that impede the development of BIM applications in China's construction industry. The results show that a lack of policy guidance and the restriction of relevant laws are the most critical hindering factors. This research contributes to the research of the hindering factors of BIM applications in China and can assist decision makers in formulating appropriate strategies to promote the application and development of information BIM technology in China's construction industry. [ABSTRACT FROM AUTHOR]

The rapid development of urbanization in China in recent years has resulted in the production of large amounts of construction waste, which has placed certain constraints on the sustainable development of the construction industry. This study measures the environmental efficiency of construction waste generated in China from static and dynamic perspectives using the data envelopment analysis and the Malmquist index with data from 30 Chinese provinces during the period from 2011 to 2020. The results showed that, from a static perspective, the environmental efficiency of China's construction waste generation has been on a generally declining trend year by year, and the overall level is still not too high. At the regional level, there is a stepwise decline in the eastern, central, northeastern, and western regions. From a dynamic point of view, the overall Malmquist index in China has an average value of 1.016, indicating that the level of environmental efficiency of construction waste generation in China is in a state of improvement. From a regional perspective, the Malmquist index is highest in the east, indicating that the level of environmental efficiency of construction waste generation in the eastern region is developing well. [ABSTRACT FROM AUTHOR]

Biological carbon pump (BCP) inefficiency was first observed in the South China Sea (SCS) throughout the 1997–1999 El Niño Southern Oscillation (ENSO) event, but the BCP usually recovers its efficiency when the climate conditions change from El Niño to La Niña conditions in the Pacific Ocean. Enhanced stratification and Kuroshio intrusion led to weak mixing and oligotrophic conditions in the sunlit layer of the SCS during the 1997/1998 El Niño phase, but the particulate organic carbon (POC) flux was comparable to the climatological mean due to the ballast effect of increased lithogenic material and CaCO3 flux. The deepened thermocline rendered the recovered mixing less effective in replenishing subsurface nutrients and subsequently lowered POC flux during the 1998/1999 La Niña phase. Both scenarios were characterized by decreased siliceous plankton but a stimulated calcareous plankton contribution, which reduced BCP efficiency, resulting in a unique asymmetric response to the ENSO in the SCS. Plain Language Summary: The El Niño‐Southern Oscillation (ENSO) in the Pacific Ocean is one of the most important ocean‐atmosphere coupled climatic phenomena on Earth, and the ENSO in turn influences marine biogeochemical cycles and the biological carbon pump (BCP). Usually, as climate conditions transition from the El Niño to La Niña phases, the weakened BCP rebounds to a highly productive level in the central and eastern Pacific. However, the BCP exhibits an asymmetric response to the ENSO in the South China Sea (SCS), the largest tropical marginal sea of the Pacific Ocean. We show that strengthened stratification of the upper water column and enhanced oligotrophic Kuroshio intrusion led to impoverished in bioavailable nutrients near the surface, caused fewer siliceous plankton compared to calcareous plankton, and thus resulted in an inefficient BCP in the 1997/1998 El Niño phase. In contrast, the deepened thermocline prevented the replenishment of nutrients from the subsurface, subsequently inhibiting the rebound of primary production and deep biogenic flux during the 1998/1999 La Niña phase. This study may aid in understanding the response of the BCP to ENSO events in marginal seas and improve predictions of global ocean carbon storage. Key Points: The South China Sea biological carbon pump does not rebound from the 1997/1998 El Niño to La Niña phase as expectedThe enhanced stratification and Kuroshio intrusion are responsible for the low opal:CaCO3 ratio of sinking particles in the El Niño phaseThe deepened thermocline prevents the diapycnal nutrient supply and the recovery of the biological carbon pump in the La Niña phase [ABSTRACT FROM AUTHOR]

The leaders of construction innovation in China promote the integration of production best practices such as design for Excellence (DfX) in industrialized construction (IC) projects as a strategic path to leverage radical performance improvements in productivity, cost, quality, circularity, and sustainability. Despite its maturity in the manufacturing industry, the implementation of DfX methods in China's IC projects remains low. One widely cited reason for the sluggish interest is a poor understanding of the holistic business benefits that DfX methods could offer in IC projects. This study identified and evaluated 23 perceived benefits of DfX methods in IC projects in China. Quantitative data were collected using structured questionnaires administered to 229 IC academics and industry practitioners in China. Statistical analysis showed that all the benefits were perceived as significant. Based on mean significance indices, the top five perceived significant benefits include: "improves component design and production efficiency," "facilitates standardization and customization," "reduces labor requirements and improves productivity," "reduces labor, inventory and development costs," and "reduces material and construction wastes." The study grouped the benefits into four clusters, namely, improved project design productivity, efficiency, and management; shortened design and construction time; life cycle cost savings; and improved flexibility, adaptability, and circularity. This study constitutes the first holistic evaluation of the benefits of DfX methods in IC projects. The evaluated benefits may serve as a basis for measuring the business benefits to justify investments in DfX in IC projects. The outcome constitutes a starting point for developing evidence-based DfX performance measurement metrics, indicators, and tools in the future. [ABSTRACT FROM AUTHOR]

Purpose: Construction workers are frequently exposed to safety hazards on sites. Wearable sensing systems (e.g. wearable inertial measurement units (WIMUs), wearable insole pressure system (WIPS)) have been used to collect workers' gait patterns for distinguishing safety hazards. However, the performance of measuring WIPS-based gait parameters for identifying safety hazards as compared to a reference system (i.e. WIMUs) has not been studied. Therefore, this study examined the validity and reliability of measuring WIPS-based gait parameters as compared to WIMU-based gait parameters for distinguishing safety hazards in construction. Design/methodology/approach: Five fall-risk events were conducted in a laboratory setting, and the performance of the proposed approach was assessed by calculating the mean difference (MD), mean absolute error (MAE), mean absolute percentage error (MAPE), root mean square error (RMSE) and intraclass correlation coefficient (ICC) of five gait parameters. Findings: Comparable results of MD, MAE, MAPE and RMSE were found between WIPS-based gait parameters and the reference system. Furthermore, all measured gait parameters had validity (ICC = 0.751) and test-retest reliability (ICC = 0.910) closer to 1, indicating a good performance of measuring WIPS-based gait parameters for distinguishing safety hazards. Research limitations/implications: Overall, this study supports the relevance of developing a WIPS as a noninvasive wearable sensing system for identifying safety hazards on construction sites, thus highlighting the usefulness of its applications for construction safety research. Originality/value: This is the first study to examine the performance of a wearable insole pressure system for identifying safety hazards in construction. [ABSTRACT FROM AUTHOR]

Smart city development plays an important role in achieving urban sustainability. This paper uses mapping of knowledge domain (MKD) analysis to review 965 studies concerning smart city development and urban sustainability (SCDUS). The most influential journals, scholars, articles, keywords, and regions in the SCDUS research field are identified. Research findings also reveal four prevailing topic clusters in the current SCDUS field, namely information technology, energy and environment, urban transportation and mobility, and urban policy and development planning. Potential research frontiers are further proposed. The findings contribute to a better understanding of the development of current SCDUS research. [ABSTRACT FROM AUTHOR]

Tunnel engineering is affected by a variety of factors, which results in large detection errors in tunnel engineering. In order to improve the monitoring effect of tunnel engineering, based on BPNN and MARS machine learning regression algorithm, this research constructs a tunnel engineering monitoring and prediction model. Moreover, the gray residual BP neural network designed in this study uses a series combination, and the residuals obtained from the gray model are used as the input data of the BP neural network, and the output of the combined model is used as the prediction result. By applying the monitoring data of the convergence of the upper surrounding of the tunnel surface section and deformation of the arch subsidence, it is verified that the proposed method based on the combined model of BPNN and MASR can predict and analyze the tunnel deformation monitoring data very well. [ABSTRACT FROM AUTHOR]

Objective To explore whether different drainage methods have positive effects on HIV positive patients with cryptococcal meningitis (CM). Methods From January 2017 to December 2019, 40 patients with HIV positive CM were treated in the Department of Infectious Diseases of the First Affiliated Hospital of Guangxi Medical University and Nanning Infectious Diseases Hospital Affiliated to Guangxi Medical University. 20 patients with continuous lumbar drainage were selected as the observation group and 20 patients with regular lumbar puncture drainage were enrolled into the control group. The clinical manifestations, CD4 count, cerebrospinal fluid examination and cryptococcal ink staining results of patients before and after treatment were recorded. Results There was no significant difference in general data between the two groups before treatment (P>0.05). After treatment, the white blood cell count [(28.70±12.04)x106/L vs(68.80±34.71)x106/L] and protein content [(477.25±198.61)mg/L vs(712.15±427.89)mg/L] in cerebrospinal fluid decreased significantly in the observation group, and similar results were found in the control group (P<0.001). The CD4 count [observation group(31.30±22.00)cells/μL, control group(27.70±20.18)cells/μL], cerebrospinal fluid sugar [observation grou(3.41±0.62)mmol/L, control group(2.80± 0.77)mmol/L] and chloride [observation group(127.78±9.47)mmol/L, control group(125.25±8.03)mmol/L] in the two groups were significantly higher than those before treatment (P<0.05). There were significant differences in CD4/CD8, leukocyte count and sugar content between the two groups (P<0.05). After treatment, the symptoms of headache and nausea/vomiting in the observation group were better than those in the control group. Finally, continuous lumbar drainage was effective in 15 cases and ineffective in 5 cases, regular lumbar puncture drainage was effective in 7 cases. Conclusion In the treatment of cryptococcal meningitis, continuous lumbar drainage can quickly relieve clinical symptoms, accelerate the renewal of cerebrospinal fluid and shorten the clearance time of pathogens, which is worthy of clinical application. [ABSTRACT FROM AUTHOR]

Construction and demolition (C&D) waste accounts for a large proportion of solid waste, thus effective C&D waste management is essential for promoting sustainable development. In Hong Kong, the government has promulgated a series of policies to encourage related stakeholders to implement effective C&D waste management. However, the overall status remains not satisfactory and has a great potential for further improvement. In this circumstance, the aim of this study is proposing solutions for further improvement of effective C&D waste management in Hong Kong. Based on a comprehensive content analysis of seven selected countries and two rounds of focus group meetings with local experienced professionals, prevailing C&D waste management policies and successful practices were identified and their feasibility of implementation in Hong Kong was discussed. Results revealed that non‐inert waste recycling is a key for improving the C&D waste management in Hong Kong to a higher level. A "3R + I" principle was suggested to be implemented in Hong Kong instead of the currently employed "3R" principle. Four solutions, namely promulgation of more specialized regulations, adoption of advanced recycling technologies, development of mature recycling markets, and implementation of high landfilling costs, were identified as the key directions for future improvement of C&D waste management in Hong Kong. The identified C&D waste management policies and the research methods used in this study can be employed in other countries or regions which are at different C&D waste management levels and economic status to form their own applicable policy framework. [ABSTRACT FROM AUTHOR]

The present paper adopts the dimensionless depth-averaged continuum model for avalanches to study interactions between an avalanche and obstacle. Three approaches are used to represent the effect of an obstacle on an avalanche. The first is to include the obstacle as the terrain, the second is to exclude the obstacle from the computation domain, and the third is to define the avalanche–obstacle interaction force with a new mathematical expression proposed in this paper. Combined with the three obstacle treatment approaches, we simulate the flow process of an avalanche bypassing different heights of obstacles placed either in the inclined plane or deposit zone. Hydrodynamic model and S–H theory are comparatively studied in the simulation of an avalanche bypassing a high dam in the inclined plane. In the simulation of avalanche striking a low dam in the inclined plane, the first and third obstacle treatment approaches are systematically compared. The effect of the coefficient of friction acting between the side walls and avalanche and the effect of the angle of basal friction are investigated by fixing a cuboid in the deposit zone. Computed deposit configuration (a); computed sequences at four time points represented by different colors (b); grains overtopping a dam as captured adopting the third approach of obstacle treatment (c); the evolution of avalanche depths with different drag coefficients during the flow process at two positions (d) [ABSTRACT FROM AUTHOR]

The construction industry consumes substantial water resources. Thus, there is a necessity to adopt effective water-saving measures to reduce water consumption in construction projects. The aim of this paper is providing a strategic framework of water-saving measures for different phases of a construction project. To start with, the prevailing green building rating tools were investigated to explore the alternative water-saving measures. Then, a comparative analysis utilizing relative significance indexing was conducted to identify the foci of water-saving measures in various green building rating tools. Based on the derived results, ten water-saving measures, namely rainwater harvesting, usage of recycled water, NEWater, water-saving technologies, water-saving devices, water-saving efficiency, water monitoring system, monitoring of major water uses, leak detection, and continuous water monitoring, were identified. These measures were further categorized into three strategic aspects, such as water sources substitution, water consumption reduction, and water use monitoring. Based on the results, a strategic framework was developed for reducing water consumption and improving water use efficiency. The developed framework can serve as a systematic guideline for formulating water-saving schemes in different stages of construction projects. [ABSTRACT FROM AUTHOR]

Time series data from a sediment trap at approximately 1,000‐m depth in the northwestern South China Sea, July 2012 to April 2013, were used in combination with remote sensing and shipboard physical and biogeochemical data to quantify the effects of multiscale physical processes on sinking particle fluxes and the function of the local biological carbon pump. Total mass flux and the fluxes of its primary components—particulate organic carbon, calcium carbonate, opal, and lithogenic matter—exhibited similar temporal trends, with three conspicuous high‐flux events. These events occurred in the summer, autumn, and winter, attributable to upwelling, aerosol deposition, and the northeast monsoon, respectively. Together, these events accounted for only 40% of the total time but approximately 80% of the 10‐month total mass flux (21% during the upwelling event, 23% during the aerosol event, and 36% during the northeast monsoon event). Each event contributed its own unique biogeochemical overprint. For example, Calcareous phytoplankton benefited from both the upwelling and aerosol deposition events, but siliceous phytoplankton benefited more than calcifiers during the upwelling conditions. The biogenic sinking particles were primarily marine authigenic, while the lithogenic matter was mainly resuspended sediment from the neighboring slope. The high flux of lithogenic matter was due to scavenging by sinking organic matter and the ballasting effect, especially during the high‐flux periods. This study illustrates that episodic intraseasonal physical processes are as important as the most common major seasonal event—the northeast monsoon—in modulating the strength of the South China Sea biological carbon pump. Plain Language Summary: Sinking particles are the most important carriers of matter and energy within the marine biological carbon pump, which largely determines the ocean's capacity to sequester atmospheric carbon dioxide (CO2) over century timescales. Multiscale physical processes are important in modulating the strength and efficiency of the biological carbon pump, but the mechanisms and contributions of different physical forcings on mesopelagic sinking particle fluxes in the South China Sea (SCS) are still poorly known. Based on time series data from a sediment trap at approximately 1,000‐m depth as well as upper layer physical and biogeochemical data, we have found that three discrete high‐flux events in the northwestern SCS were driven by upwelling, aerosol deposition and the northeast monsoon. Together, the three events accounted for nearly 80% of the total mass flux and nearly 75% of the total particulate organic carbon flux. Each event contributed nearly equal to the total particulate organic carbon flux, but each also contributed its own unique biogeochemical overprint. Our findings confirm the importance of multiscale physical processes on SCS biogeochemistry and in particular highlight the roles of upwelling and aerosol deposition, which are as important as the northeast monsoon in modulating the strength of the SCS biological carbon pump. Key Points: Trapped sinking particles were 36% biogenic (primarily marine authigenic) and 64% lithogenic (mainly neighboring resuspended sediment)Three discrete events driven by upwelling, aerosol deposition, and the northeast monsoon contributed nearly 80% of the total particlesIntraseasonal events were as important as the seasonal monsoon in modulating the strength of the local biological carbon pump [ABSTRACT FROM AUTHOR]

High capital cost is a significant hindrance to the promotion of prefabrication. In order to optimize cost management and reduce capital cost, this study aims to explore the latent factors and factor analysis evaluation model. Semi-structured interviews were conducted to explore potential variables and then questionnaire survey was employed to collect professionals' views on their effects. After data collection, exploratory factor analysis was adopted to explore the latent factors. Seven latent factors were identified, including "Management Index", "Construction Dissipation Index", "Productivity Index", "Design Efficiency Index", "Transport Dissipation Index", "Material increment Index" and "Depreciation amortization Index". With these latent factors, a factor analysis evaluation model (FAEM), divided into factor analysis model (FAM) and comprehensive evaluation model (CEM), was established. The FAM was used to explore the effect of observed variables on the high capital cost of prefabrication, while the CEM was used to evaluate comprehensive cost management level on prefabrication projects. Case studies were conducted to verify the models. The results revealed that collaborative management had a positive effect on capital cost of prefabrication. Material increment costs and labor costs had significant impacts on production cost. This study demonstrated the potential of on-site management and standardization design to reduce capital cost. Hence, collaborative management is necessary for cost management of prefabrication. Innovation and detailed design were needed to improve cost performance. The new form of precast component factories can be explored to reduce transportation cost. Meanwhile, targeted strategies can be adopted for different prefabrication projects. The findings optimized the capital cost and improved the cost performance through providing an evaluation and optimization model, which helps managers to evaluate cost management level of prefabrication and explore key inducers for high capital cost. [ABSTRACT FROM AUTHOR]

Building information modeling (BIM) can theoretically facilitate collaboration among diverse design participants in construction projects, but in practice, its implementation tends to prolong the design period. Existing literature has examined some technical and managerial causes of this problem but still lacks an overall coverage of related factors. This study aims to identify the comprehensive factors affecting the teamwork efficiency in China's BIM-based collaborative design, and to investigate the critical factors and their interactions. Based on the input-process-output theory, this study initially established a hypothetical model. Potential factors were further identified through the literature review and semi-structured interviews. Questionnaire survey was conducted, and structural equation modeling was used for analysis. The results indicated that the team cooperation atmosphere is the most significant factor, followed by the collaborators' learning ability, comfort of the working environment, BIM software function, and the characteristics and arrangement of the design task (CADT). Besides, the CADT negatively affects the teamwork efficiency through the human interaction process, while other factors exert positive impacts by affecting both the personal work process and the human interaction process. The findings can help design units to determine the management focus of BIM-based collaborative design and prioritize the allocation of limited resources accordingly to maximize teamwork efficiency. [ABSTRACT FROM AUTHOR]

Hong Kong is a densely populated city with high-rise developments, and as in other metropolitan cities, the amount of waste generated from construction projects in the city is increasing annually. The capacity of existing landfills is expected to be saturated by the 2020s. Construction waste management has been implemented for years but the performance is still not satisfactory. The aim of this research paper is to explore and formulate strategies and measures for effective construction waste management and reduction in highly urbanized cities such as Hong Kong. A desktop study on construction waste management practices was carried out for a preliminary understanding of the current situation in Hong Kong. Semistructured interviews and focus group meetings were further conducted to shed light on how to improve construction waste reduction and management in Hong Kong. The main contributions of this research study are the potential short-term, medium-term, and long-term strategies, which are related to the design stage, tender stage, construction stage, and government support. The five major strategies recommended are financial benefits to stakeholders, public policies in facilitating waste sorting, government supports for the green building industry, development of a mature recycling market, and education and research in construction waste minimization and management. [ABSTRACT FROM AUTHOR]

Construction management can be regarded as a complex and dynamic system. In recent years, system dynamics (SD) has been widely applied to solve the complex and dynamic problems in the construction management. However, there is a lack of a scientometric analysis to investigate SD applications in construction management from an objective perspective. To fill out this research gap, this study retrieved a total of 222 relevant articles from the Scopus database. Then, VOSviewer was employed to analyze the collected literature from five aspects (i.e., co-authorship, published journals, co-occurring keywords, article citations, and regions). Based on the analysis results, four mainstream research themes were identified and discussed, including "risk management", "waste management", "energy management", and "construction productivity". In addition, future research directions, such as "construction risk allocation in PPP projects", "evaluating the economic feasibility of construction waste landfilling centers", "identifying the variables affecting lighting infrastructure energy consumption", and "assessing construction productivity for technology-intensive activities", were proposed. The contribution of this study lies in that it helps both scholars and practitioners to solve the complex and dynamic problems in construction management. [ABSTRACT FROM AUTHOR]

Prefabrication is a technology that can reduce the material consumption during the construction process. Thus, it is regarded as a technology that be of assistance in the pursuit of sustainable development in the construction industry. In China, a series of policies has been formulated to promote the implementation of prefabrication; however, the effectiveness of these policies has not been investigated. The aim of this paper is to evaluate the effectiveness of the current prefabrication incentive policies in China. To achieve this research aim, a policy framework was first developed in order to understand the existing policies. Then, four indicators—namely, the number of prefabricated component production enterprises, the prefabricated floor area, the prefabricated building market size, and the expected prefabricated building area ratio—were selected to evaluate each policy's effectiveness. It was found that the growth rates of these four indicators had increased slowly, and had even shown declining trends before 2015; however, with the incentive policies promulgated after 2015, the growth rates have increased. This study is of value not only in helping readers to understand the existing framework of incentive policies in China, but also in revealing the effectiveness of the identified prefabrication incentive policies. These research findings can also provide insights useful for policy formulation in other jurisdictions for the promotion of prefabrication. [ABSTRACT FROM AUTHOR]

Culture-led regeneration projects (CRPs) have been identified as an effective means for enhancing the sustainable development of cities. Related topics have been investigated; however, relatively little information is known about what factors are critical for achieving success in these kinds of regeneration projects. Based on a literature review and five case studies, this study contributes to the body of knowledge by identifying 25 critical success factors (CSFs) for managing CRPs in China. A questionnaire survey was designed to evaluate the relative importance of these factors from practitioners' and researchers' perspectives. In addition, a factor analysis was carried out to group these CSFs into five categories, namely government policies and culture-led regeneration strategies, stakeholder management and financing support, technical solutions for CRPs, social security, and industry development. The results demonstrated that cultural value management, integrating cultural development with urban planning, adopting sustainable development principles, reconstructing the city image and brand, and the availability of culture-led planning methods played the most important roles in the success of CRPs. The findings of this study can help practitioners enhance their regeneration project performance. [ABSTRACT FROM AUTHOR]