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With a large number of new energy vehicles being put into use, it is the general trend for traditional fuel vehicles to withdraw from the market in an orderly manner. Determining the optimal ratio between them in this process is of great significance to the low-carbon sustainable development of cities. Therefore, considering the constraints of urban automobile development planning and air pollution prevention and control policies, a multi-objective model to minimize pollutants and costs is constructed in this paper. Through model calculation and sensitivity analysis of dynamic impact relationship of different types of vehicles, it is determined that when new energy vehicles account for around 36% in Beijing, 57% in Shanghai and 46% in Guangzhou, the pollutant emissions can be minimized without causing a significant increase in social costs. Additionally, compared with 2030, Beijing, Shanghai and Guangzhou can achieve emission reductions of 320,000 tons, 200,000 tons and 250,000 tons, respectively, in 2050 if they implement the policy of banning the sale and delisting of fuel vehicles, which could provide suggestions for the guidance of the low-carbon development plan of the automobile industry. [ABSTRACT FROM AUTHOR]

This paper explores how the busy mindset, a common mindset in modern society, affects consumers' evaluations of new products. It proposes that a busy mindset increases the consumer's evaluation of new products and outlines the mediating role of self-efficacy and the moderating role of perceived economic mobility. The study enriches the research on busy mindsets and new product evaluations and makes practical contributions to enterprises in management and marketing. The paper used three formal experiments (Ns = 196, 84, 277). Participants in studies 1 and 2 were students recruited from different colleges in Guangzhou city, China. The sample in study 3 were adults from all over China recruited from www.wjx.cn. This research shows that activating participants' busy mindsets will increase their evaluations of new products, with self-efficacy as the mediator and economic mobility as the moderator. There may still be other mediating explanations, such as a sense of control. Meanwhile, this study's current manipulation method of busyness mainly focuses on writing tasks; thus, researchers can adopt more new manipulation methods of busyness in a realistic context. Marketers can improve consumers' evaluations and attitudes to new products by stimulating their busy mindsets and briefly activating their highly perceived economic mobility. Unlike previous studies, this research distinguishes between time pressure and a busy mindset. Meanwhile, our results show that the effect of a busy mindset differs from the effect of time pressure on new product evaluation. [ABSTRACT FROM AUTHOR]

With the rapid growth rate of China's economy, the extensive pattern of economic growth of "high energy consumption and low output" has magnified the constraints of energy issues on China's economic development and environmental protection, which highlights the importance of improving energy efficiency. As one of the three major economic zones in China, the Pearl River Delta region also faces high energy consumption and pollution emissions while developing at a high speed. Hence, improving the energy efficiency of the Pearl River Delta region is needed, as it not only is conducive to driving its development of the surrounding green economy, but also promotes the subsequent sustainable economic development. However, there are few literatures on the calculation and analysis of energy efficiency in the Pearl River Delta, and lacking a systematic analysis of input–output index system of energy efficiency measurement. Therefore, this paper calculates the energy efficiencies and the Malmquist indexes based on the panel data of the nine cities in the Pearl River Delta from 2005 to 2019 through super-efficiency SBM model and Malmquist index method by using MAXDEA and MATLAB software. The result illustrates that all regions in the Pearl River Delta except Guangzhou and Shenzhen show obvious energy inefficiency, which is mainly caused by the imbalance between technical efficiency and scale efficiency. Based on the calculation results, this paper gives some relevant suggestions for the further approach of energy reform in the Pearl River Delta according to the calculation results. [ABSTRACT FROM AUTHOR]

Historic timber structures face substantial fire loads and complex fire risks. Subsequent renovations and utilization may influence their fire safety performance. Therefore, accurately predicting indoor fire development in historic buildings and assessing their fire safety performance is crucial. Numerical fire simulation is currently at the forefront of analyzing and assessing fire risks in historic buildings. However, there is a shortage of globally accessible historic building fire data. This paper proposes a method to determine fire scenarios, peak heat release rates, and development curves of indoor fires in wooden historic buildings through a fire load investigation. Using the Guangzhou ancestral hall as an example, PyroSim fire dynamics simulation software is employed to calculate fire development and assess the available safe evacuation time. The simulation results are subsequently input into the Pathfinder evacuation simulation software to ascertain the required safe evacuation time for indoor occupants. A comparative assessment is conducted to evaluate the fire safety performance before and after the renovation of historic buildings. The research findings indicate that installing closed glass curtain walls in the courtyards of ancestral hall buildings in Guangzhou accelerates the infiltration of smoke during fires, leading to rapid fire spread and long-distance ignition, significantly reducing the time available for safe evacuation. Therefore, when renovating and utilizing the ancestral hall buildings in Guangzhou, the installation of ventilation and smoke extraction systems should be prioritized to slow down fire development. Additionally, controlling the number of indoor occupants is an effective management measure to mitigate fire damage in historic buildings. [ABSTRACT FROM AUTHOR]

The study of clan paintings reveals a shift in perspective from art aesthetics to cultural connotations to cultural identity, yet literature seldom discusses the relationship between art and kinship culture. Taking the murals of ancestral hall architecture in Guangzhou as an example, this paper utilizes text mining to identify factors influencing its decorative art. It reveals the traditional rites' artistic expression through dimensions of characters' demeanor and the transmission of content values, offering a fresh perspective for heritage value research. Findings: (1) themes and implications are mostly oriented towards positive value transmission, transitioning from idealistic layman life to the realism of lower-class existence, emphasizing humanization; (2) the extroverted portrayal of characters contrasts with the dignified, restrained etiquette of traditional rites, with some characters' portrayal and facial expressions exuding approachability; (3) murals conveying positive emotions are mostly related to longevity, auspiciousness, fortune, and heroic deeds, while those conveying negative emotions mainly involve elderly male figures, reflecting a content bias related to characters; (4) historical allusion murals with complex content reduce the emotional resonance and arousal efficiency of the viewer; (5) incomplete mural content increases negative emotions in perceivers, highlighting the impact of mural preservation on emotional resonance. To delve into the formation of clan painting art, it is essential not only to interpret the diversity of its patterns but also to demonstrate the representation of its social attributes in decorative art. The formation of clan painting decorative art exhibits kinship cultural attributes, epitomizing the essence of traditional ceremonial thought. [ABSTRACT FROM AUTHOR]

The reorganization of the global production network and the increased mobility of urban-rural elements have accelerated the differentiation of rural spaces, resulting in a trend towards specialization in rural areas. This paper focuses on the concept of specialization, and takes a renowned bonsai specialized village in Guangzhou City, China as a typical case to explore its transformation and development process, action logic and coupling mechanism with the social governance. The results show that: 1) the development of rural specialization in Ruiling Village is shaped by several key actors, such as local governments, grassroots organizations, villagers, social organizations, policies, markets and infrastructure. The transfer of these key actors and the reconstruction of actor-networks in different stages have an important influence on the transformation and realization of rural development goals. 2) Through subjects-driven, organization management and resource connection, social governance supports the specialization of rural industrial organization, operation, technology and mode. The governance structure shifts from decentralization to networking, refinement and integration. A coupling community of social governance and specialization is created by the social governance system of 'local government-grassroots organizations-economic cooperatives-villagers', which links industries, industrial chains and cooperatives. 3) Social governance integrates into the value chain extension process of rural specialized development with a central, multi-level organizational structure. It promotes the construction of the whole value chain through organizational planning, resource integration and image shaping, thus realizing the value, branding and organization of the industry, as well as the integration of rural sustainable development and governance mechanism. Social governance has a profound impact on the development of rural specialization in terms of subject, structure and mode, and participates in the construction of the whole value chain of rural areas. This paper provides a new perspective for understanding the coupling effect of social governance in the rural development transformation, and promotes the rural sustainable development and governance. [ABSTRACT FROM AUTHOR]

The relationship between social factors and the formation of exported mug designs is blurred. This study addresses how they influence material design. Based on a quantitative typological analysis, this paper interprets the cultural relationships underlying the evolution of mug designs exported during the Ming and Qing dynasties. The study reveals: (1) the typology and handle styles of mugs can be categorized into six types, with a predominance of Cylindrical bodies and Ear-shaped handles. Notably, artistic emphasis is concentrated on Bulbous cup bodies and Tail outward curved handles; (2) the design of mugs in the eighteenth century exhibited diversity, morphological similarities, and feature continuity, evolving from representational (Ming Dynasty) to abstract and then to minimalistic styles (Qing Dynasty), particularly evident in the three-dimensional modeling of handles for ergonomic comfort (transitioning from a singular Outward curved form to Ear-shaped form, and then to Entwined branch form); (3) the body shape of mugs transformed from Arc-barrel bodies to Bulbous bodies (focusing on heat retention), and eventually to Cylindrical bodies (prioritizing heat retention, practicality, and cost-efficiency).; (4) the volume of mugs steadily increased from the early eighteenth century, generally classified into large volume (≥ 500 ml), medium volume (200-499 ml), and small volume (< 200 ml); (5) considering the extreme range of volume (11090 ml) and height (25 cm), it indicates that these two variables do not necessarily have a direct positive correlation; (6) the low center of gravity in handle design (average width of 3.4 cm against an average height of 9.9 cm for the body) reflects considerations for the distribution of liquid weight and operational convenience. The volume of sample-10 (11127 ml) notably exceeds the typical range for tea-drinking utensils, revealing the mechanism of wealth and status symbolism. Market demand orientation emerged as the primary driver for the evolution of export mug designs during the Ming and Qing Dynasties, with adjustments in the merchant system playing a secondary role. The transformation in mug design reflects the interplay of multiple factors, with the trend toward minimalist design being a response to market demands. [ABSTRACT FROM AUTHOR]

Nowadays more private car trips have caused worse congestion due to the Covid-19 pandemic in many cities. Congestion charging is one of the taxes that is levied on vehicle owners to reduce urban traffic congestion. One of the most important reasons congestion charging is not accepted by the public is the high cost. Monitoring the state of traffic congestion in real time requires a lot of expensive installations. The purpose of this paper is to make congestion charging more accurate and acceptable using artificial intelligent algorithm. Massive real-time Global Positioning System (GPS) data provides new data for road congestion charging. The queuing length at intersections is an important measurement for the degree of traffic congestion, and it is also the basis for road congestion pricing. GPS positioning cannot provide sufficient position accuracy for lane identification of vehicles. In this study, a comprehensive model consisting of a real-time lane identification model and a real-time queue length estimation model is developed based on the traffic shockwave theory using GPS data. The comprehensive model can identify the lane where the queuing vehicle is located and estimate the real-time queue length of the lane. The proposed models were evaluated using field-collected data in Guangzhou, China. The testing results show that the proposed comprehensive model can identify lanes and estimate queue lengths with satisfactory accuracy. The model proposed in this paper provides real-time data for road dynamic pricing in a cost-effective way, which can promote the implementation of congestion charging in cities. [ABSTRACT FROM AUTHOR]

Welfare housing tenants in project-based welfare housing communities usually have very limited choice in terms of the spatial and locational characteristics of their neighborhood. However, to make city more integrated and socially-amiable, welfare housing developers and administrators should also take residents' consideration into account when developing and maintaining such welfare housing communities. In this paper, the relative importance of different spatial, locational and environmental variables from these welfare residents' perspective will be examined in some public housing projects in Guangzhou, China. In doing so, this paper proposes a resident-oriented development model for making a more sustainable and amiable welfare housing community. Based on an Analytic Hierarchy Process (AHP) framework, we find that among all the elements in neighborhood, accessible medical care is of prime importance, followed by housing quality and sense of security. According to the analysis, this paper concludes that a successful and sustainable welfare housing community goes beyond the need of merely providing accommodation. A well-designed neighborhood is needed for residents to sustain their livelihood there, especially when most of the welfare housing communities are built in the relatively remote part of the city for cheap land cost. [ABSTRACT FROM AUTHOR]

Forest fire not only seriously affects the stability of forest ecosystem, but also threatens the safety of human life and property. It is very important to evaluate and forecast the risk of forest fire. This paper takes Conghua District of Guangzhou City as the research area. Based on Landsat 8 OLI/TIRS data, Sentinel-1 data, nighttime light data, DEM data, the seven evaluation factors of fuel moisture content, land surface temperature, altitude, slope, proximity to river, proximity to road and proximity to settlement are calculated. The forest fire risk assessment index system is constructed by analytic hierarchy process. Data from 326 historical active fires obtained by NASA-FIRMS website are used to verify. The area under the ROC curve (AUC) is used to estimate the performance of the forest fire risk map. The result shows that the value of AUC is 0.791, indicating that the forest fire risk assessment index system has good applicability to Conghua District of Guangzhou City, and it can provide scientific reference for the establishment of forest fire risk assessment index system in other areas. [ABSTRACT FROM AUTHOR]

Accurate short-term traffic state prediction is a crucial requisite for control and guidance of traffic flow in the intelligent traffic system, which has attracted increasing attention in the transportation field recently. This paper tests the optimization performances of two emerging bionic algorithms, known as Cuckoo Search Algorithm (CS) and Bat Algorithm (BA). Combined with the Support Vector Regression (SVR) principle, the two aforementioned algorithms are applied to optimize the kernel function parameters in SVR. At last, the speed data of a road network in Guangzhou are collected. The prediction performances of the CS-SVR and BA-SVR models are tested after preprocessing the data. From the overall prediction rates, the CS-SVR algorithm is slightly better than BA-SVR in terms of calculating speed. Furthermore, the two algorithms are significantly superior to the traditional SVR model and long short-term memory networks (LSTM), thereby verifying their effectiveness and practicability in short-term traffic state prediction. [ABSTRACT FROM AUTHOR]

Rainwater harvesting (RWH) systems are one of the most promising technologies for water supply, but the economic viability often barricades their implementation. To assess the economic viability of decentralized RWH systems at a regional level, this paper develops a generic method to investigate the effect of variations in building characteristics on the economic performance of rainwater harvesting systems in regions with fixed water tariffs and rainfall distribution characteristics. We simulated the financial efficiency (expressed as a benefit-cost ratio) of a large number of decentralized RWH systems in Guangzhou, China. We found that the financial efficiency of the RWH systems is closely related to the catchment fraction (i.e., the ratio of rainfall catchment surface to total floor area). Based on this dimensionless parameter, we derived explicit equations expressing the financial efficiency of RWH systems using a nonlinear regression method. In addition, we validated the analytical equations by the root mean square error test, normality test, and error distribution test. This analytical solution provides a simple and generic method for forecasting the investment potential of rainwater harvesting systems. This methodology can also be adapted to other regions where the variations in local water price and rainfall data need to be considered. [ABSTRACT FROM AUTHOR]

Over-track buildings in metro depots become more and more prevalent in metropolis with the increase in population and the decrease of construction land. However, the train-induced vibration greatly reduces the comfort of occupants living in the over-track buildings. Owing to complex vibration sources and numerous transfer paths, it is a challenging task to analyze and predict the vibration characteristics accurately in the building. In this paper, a field measurement campaign of vibration was conducted in the Guanhu metro depot in Guangzhou, China. A novel formulation based on the operational transfer path analysis (OTPA) and singular value decomposition (SVD) is proposed to analyze the measured data and predict the train-induced vibration in the building. In this study, the vibration contributions from each transfer path to the target points in the building were obtained and the predominant transfer paths were identified further. Besides, the vibration at target points in the building was predicted using the vibration at path points and transmissibility functions from transfer paths. This study provides insights into the prediction and evaluation of vibration transmissions from vibration source to upper floors of over-track building. [ABSTRACT FROM AUTHOR]

Urban land change plays an essential role in the development of country's economy. Rapid and unplanned urban growth increases land surface temperature (LST) and reduces carbon storage (CS) by replacing the natural land use/land cover (LULC). This paper aims to monitor and predict the changes in urban growth patterns on LST and CS for the winter season in Guangzhou from 1989 to 2021. The integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model is used to assess the existing (1989-2021) scenario of CS. The Cellular Automata-Artificial Neural Network (CA-ANN) and Long Short Term Memory (LSTM) based Whale Optimization Algorithm (WOA) are used to predict the future LULC, CS and LST scenarios. The results indicate that an increase in urban areas by 63% causes an upsurge of high LST (≥34 °C) areas by 652 km2 and a decrease in carbon storage by 56,943.607 t from 1989 to 2021. In addition, the results demonstrate that 93% of lower temperature areas have higher CS capacity (65%), whereas 80% of higher temperature areas demonstrate a low CS capacity (89%). This study can provide effective mitigating measures for designing smart cities and valuable guidelines for ensuring environmental-friendly green cities. [ABSTRACT FROM AUTHOR]

Study on export paintings has gradually shifted from artistic form to cultural connotation, with an emphasis on cross-cultural communication. Although the economic and social dimensions of their artistic value have been explored, few studies delve into the connection between Qing-era Guangzhou's trade culture and its color characteristics. Utilizing the HSV color model and the k-means algorithm, this study analyzes the color traits of 35 export paintings depicting Guangzhou landscapes and works from the "Thirteen-houses commercial zone," revealing Qing-era Guangzhou's urban impressions and Sino-Western artistic interactions. Key findings include: (1) the hue pixel range in Guangzhou export paintings primarily spans 10°–60° and 120°–250° (dominated by red and yellow-green), saturation values range from 1–82% (primarily low saturation), and value values range from 11–94% (with a wide variance); (2) compared to traditional Chinese paintings, the transformation from pure color (正色) → inter-color (间色) → projection-perspective and light source illustrates both the blending of Eastern and Western artistic cultures and a diminishing influence of traditional ceremonial culture; (3) in contrast with Western artworks, some Guangzhou export paintings display a Westernization trend in color structures, evident in vibrant colors and stark chiaroscuro contrasts. As bespoke art commodities, export paintings microscopically reflect Guangzhou's unique trade culture and socio-political dynamics. The shifts in color schemes, integration of realistic styles, and human-centric characteristics unveil the intricate interplay between quasi-realism and transcendental aesthetics in Qing-era Guangzhou, as well as the nuanced dynamics between social capital and art within a global trade network. [ABSTRACT FROM AUTHOR]

This paper proposes a framework to identify geological characteristics (GC) based on borehole data and operational data during shield tunnelling using a fuzzy C-means algorithm. The proposed fuzzy C-means model was established by integrating the K-means ++ algorithm into the fuzzy set theory. The identified factors for GC include advance rate, cutterhead rotation speed, thrust, cutterhead torque, penetration rate, torque penetration index, field penetration index, and specific energy. Principal component analysis was employed to reduce the dimensions of these factors. The first six principal components were employed to analyse the GC and establish the input data set in the fuzzy C-means model. The types of GC were determined based on elbow method, silhouette coefficient, fuzzy partition coefficient and the geological profile from borehole data. The proposed approach was validated by a case of Guangzhou intercity tunnel construction. The results present that the proposed fuzzy C-means model can effectively determine GC and provide membership to reveal the proportion of hard rock. [ABSTRACT FROM AUTHOR]

To study urban air quality, this paper proposes a novel categorical time series model, which is based on a linear combination of bounded Poisson distribution and discrete distribution to describe the dynamic and systemic features of air quality, respectively. Daily air quality level data of three major cities in China, including Beijing, Shanghai and Guangzhou, are analyzed. It is concluded that the air quality in Beijing is the worst among the three cities but is gradually improving, and its dynamics is also the most pronounced. Theoretically, the design of our model increases the flexibility of the probabilistic structure while ensuring a dynamic feedback mechanism without high computational stress. We estimate the parameters through an adaptive Bayesian Markov chain Monte Carlo sampling scheme and show the satisfactory finite sample performance of the model through simulation studies. [ABSTRACT FROM AUTHOR]

High-speed rail (HSR) is one of the essential innovations in the field of transportation in the latter half of the twentieth century. In China, the rapid development of HSR has received increasing attention and resulted in a boost of tourism, with significant impact on the development of cities that operates HSR. To accurately comprehend how will the operation of HSR influence the regional CO2 emissions, this paper applies the modified STIRPAT model, combining with real data on high-speed rail passenger flow volume of the Beijing-Guangzhou high-speed rail Hunan section. The results show that (1) the high-speed rail operation is also a significant impact factor for regional CO2 emissions. (2) Considering the operation of HSR, the ranking of contribution rate of driving factors for regional CO2 emissions is as follows: GDP per capita, energy consumption per unit of GDP, arrival volume of high-speed rail, originated volume of high-speed rail, the proportion of coal in the energy mix, proportion of the tertiary industry, and population. (3) Surprisingly, the numerical research result shows that the operation of HSR for the cities may promote regional CO2 emissions, while the increase in urban population and the optimization of energy structure have a reducing effect on regional carbon emissions. There is a transfer effect of the operation of HSR and region development, which results in the rising of regional CO2 emissions. Thus, it is urgent to research on the decoupling of economic growth from CO2 emissions. The findings could be conducive for the government and railway company to evaluate and administrate the operation of high-speed rail and adequately deal with the relationships between the high-speed railway and regional development. [ABSTRACT FROM AUTHOR]

This paper establishes an intelligent framework for real-time prediction of trajectory deviations in the process of earth pressure balance (EPB) tunnelling. A hybrid model was developed which integrates principal component analysis (PCA) and a gated recurrent unit (GRU). PCA was adopted to mine the interrelated input parameters and reduce the accompanying data noise. A scroll window mode was implemented in the GRU to predict the shield movement in real time. The proposed PCA–GRU model was implemented and validated through a case study of the Guang-Fo intercity railway in Guangzhou, China. Another three machine learning models were also used for comparison. The results revealed that the proposed model predicted the shield moving trajectory with higher precision than other models. The implications for trajectory regulation were discussed using field data. The proposed prediction framework represents a promising solution for real-time prediction of the shield moving trajectory in EPB tunnelling. [ABSTRACT FROM AUTHOR]

With the development of urban rail transit, taking the metro train has become one of the main modes of transportation, and passengers have an increasing demand for the comfort of taking the metro trains. This paper mainly discusses the impact of noise and vibration caused by metro train on passengers. All 13 metro lines in Guangzhou, China, were selected to conduct the questionnaire survey on the subjective perception of 601 respondents. At the same time, noise and vibration measurements were carried out in the train. The results show that the distribution of noise and vibrations along the metro lines is not uniform, and 50.6% of the interviewees are disturbed by noise. Wheel-rail squeal was found to be the most annoying and disturbing noise source. Three dose-response relationships for noise, vertical vibration, and horizontal vibration are proposed, respectively. The proposed dose-response relationship can be applied to the evaluation of noise annoyance or vibration perception in an environment similar to metro lines. Once the noise or vibration level of a metro line is obtained, the noise disturbance or vibration perception can be estimated. As for the dose-response relationship of vibration perception, people's sensitivity to vibration is much lower than that to noise. Horizontal vibrations are more acceptable to passengers, while vertical vibrations are more disturbing to passengers. The results are helpful to predict the noise annoyance and vibration perception of train passengers between metro stations, and to achieve the purpose of designing effective noise and vibration reduction measures. [ABSTRACT FROM AUTHOR]

Taking the entrepreneurial activities as a local phenomenon, this paper aims to investigate the way that individual's active embeddedness in cluster environment influences on the entrepreneurial intentions and locational preference of the nascent entrepreneurs. Drawing on the employee survey data in the Tianhe Software Park in Guangzhou, China, the empirical results have distinguished between impacts of cluster on nurturing and anchoring nascent entrepreneurs. Firstly, it has been shown that the awareness of role model entrepreneurs in the cluster enhances the entrepreneurial intentions of the employees. Secondly, the embeddedness in personal relations with suppliers and customers has proven to exert significant impact in the locational preferences toward the cluster of origin. Overall, the findings of the paper have shed light on how cluster environment poses its impact on nascent entrepreneurs through different mechanisms in the different decision-making processes. The implications of the findings for entrepreneurial policy are discussed in the concluding section. [ABSTRACT FROM AUTHOR]

Online comments have become an important tool for disabled guests because of lower physical movement requirements. In order to illustrate and evaluate disabled guests' decision-making characteristics, this paper has used two steps for studying: (1) Data mining technology to collect e-comments from C-trip (www.ctrip.com) of 97 hotels in the cities of Beijing, Shanghai, Hangzhou and Guangzhou. Over 260,000 words were collected and analyzed by using ROSTcm software for this research. (2) Examined the relationship between the credibility and the perceived risk of disabled guests for their behavioral intentions. The result of this study has showed that: (1) Disabled guests pay more attention to the hotel barrier-free facilities, hotel barrier-free facilities, hotel personalized service, location accessibility, and the attitude and atmosphere of the hotel. (2) Disabled guests show positive attitude towards the hotel, and a neutral attitude accounting for 25.86% which indicates that the hotel industry still has much improving room especially with regards to disabled accessible guestrooms and accessibility. (3) Electronic Word-of-Mouth (eWOM) source credibility has a great influence on the overall perceived risk of the review of disabled guests because they are more likely for seeking internet comments for their lodging decision-making than other common guests. eWOM rational management can reduce the overall potential risk for disabled guests. (4) Hotels can enhance disabled guests' decision-making by advanced eWOM management. The study illustrated that disabled guests who used eWOM could be better managed and reduce potential risks when making decisions. As a result, this study also found that with better management of eWOM, it could help to meet the potential market for the disabled guests and at the meanwhile attract more customers because of higher social reputation. [ABSTRACT FROM AUTHOR]

Dengue transmission is climate-sensitive and permissive conditions regularly cause large outbreaks in Asia-Pacific area. As climate change progresses, extreme weather events such as heatwaves and unusually high rainfall are predicted more intense and frequent, but their impacts on dengue outbreaks remain unclear so far. This paper aimed to investigate the relationship between extreme weather events (i.e., heatwaves, extremely high rainfall and extremely high humidity) and dengue outbreaks in China. We obtained daily number of locally acquired dengue cases and weather factors for Guangzhou, China, for the period 2006–2015. The definition of dengue outbreaks was based on daily number of locally acquired cases above the threshold (i.e., mean + 2SD of daily distribution of dengue cases during peaking period). Heatwave was defined as ≥2 days with temperature ≥ 95th percentile, and extreme rainfall and humidity defined as daily values ≥95th percentile during 2006–2015. A generalized additive model was used to examine the associations between extreme weather events and dengue outbreaks. Results showed that all three extreme weather events were associated with increased risk of dengue outbreaks, with a risk increase of 115–251% around 6 weeks after heatwaves, 173–258% around 6–13 weeks after extremely high rainfall, and 572–587% around 6–13 weeks after extremely high humidity. Each extreme weather event also had good capacity in predicting dengue outbreaks, with the model's sensitivity, specificity, accuracy, and area under the receiver operating characteristics curve all exceeding 86%. This study found that heatwaves, extremely high rainfall, and extremely high humidity could act as potential drivers of dengue outbreaks. [ABSTRACT FROM AUTHOR]

The bark-eating caterpillar, Indarbela obliquifasciata Mell has become a major pest of garden plants in Guangzhou, China. However, little is known about the sex identification of either adults or pupae. In this paper, according to a comparative morphological study of 55 adults and their corresponding pupae or puparia, we concluded a rapid and accurate method for identifying its sexuality. The results showed a distinct sexual dimorphism in both adults and pupae. In male adults, the antennae are broadly bipectinate, and the ctenii are long with plumose sensory setae. While in female adults, the antennae are narrowly bipectinate, and the ctenii are short with rare setae. In male pupae, the spines on 8th abdominal segment are distributed in a circle, and segments 4–7 are mobile. While in female pupae, the spines on 8th abdominal segment are partially absent on ventral side, and with a short slit at middle part, and segments 4–6 are mobile. The results of this study are of great significance for the field investigation of the sex ratio of adults and pupae and for the study of female pheromones. [ABSTRACT FROM AUTHOR]

Prefabricated construction is becoming increasingly prevalent, however, it is rarely applied in underground constructions, except for tunnel linings, due to the difficulties that arise in jointing various prefabricated components in underground conditions. To solve the vertical location problem of embedded mechanical couplers during the construction of wall–beam–strut joints for a prefabricated metro station, a new connection using welded steel plates is proposed. In this paper, four full-scale specimens of wall–beam–strut joints connected using welded steel plates and mechanical couplers were experimentally tested under monotonic and low-reversed cyclic loading conditions. The testing results were analysed in terms of the ultimate bearing capacity, failure mode, hysteresis, skeleton curve, stiffness degradation, energy dissipation and strain of the reinforcement bars. Notably, the two kinds of joints had similar ultimate bearing capacities and failure modes, but the crack distributions on the tops of the waler beams were different. For the specimens with the welded steel plate connection, tensile horizontal cracks first appeared on the top surface of the beam, where the welded steel plate was located, and then coalesced gradually; however, this cracking pattern was not observed during the experimental test of the specimens connected with the mechanical couplers. Furthermore, it was determined that the energy dissipation and ductility of the welded steel plate connection were better than those of the mechanical coupler connected joint, because the steel plate could redistribute the internal force in the joint and increase the stiffness. It was concluded that the proposed welded steel plate connection could be more favourable than the mechanical coupler connection in the construction of a prefabricated metro station in Guangzhou. Moreover, the results obtained from these experiments could provide guidelines for the corresponding connections employed in underground-prefabricated structures. [ABSTRACT FROM AUTHOR]

This paper summarises the stratigraphy, tectonic structure, geomorphology, hydrogeology and engineering geology in Guangzhou, China, and analyses the relevant geo-hazards and countermeasures during subway construction. The ages of the geological materials found in Guangzhou range from the Proterozoic era to the Cenozoic era. The bedrock is generally made up of sedimentary rock and weathered granite strata covered by soil with a thickness ranging from 2 to 20 m. The presence of underground karst caves, active faults and fissure water together with high piezometric levels leads to difficulties in shield tunnelling in Guangzhou. A case history, where two tunnels and one subway station on the Guangzhou Metro Line 7 were constructed, is referred to in order to analyse the mechanism between geological formations and geo-hazards. Three potential geo-hazards are listed: (1) water ingress and strata erosion, (2) ground surface settlement and (3) sinkholes; and their implications for shield tunnelling in Guangzhou are summarised and discussed. To mitigate the risk of these geo-hazards, a series of countermeasures, comprising (1) optimising TBM cutting tool design, and tunnelling parameters, (2) grouting to enhance watertightness and stiffness of strata and (3) injecting bentonite slurry and foam into the head chamber, are recommended in this paper. [ABSTRACT FROM AUTHOR]

The middle class in metropolitan Chinese cities has become an important social group. With the rapid development of urbanization and constant advancement of suburbanization, the middle class has increasingly come to influence city traffic. Research into middle-class commuting activities thus has practical significance for improving traffic congestion and reducing the commuting burden in metropolitan cities. Based on a dataset formed by 816 completed surveys, this paper analyzes the commuting mode, time and distance of middle-class residents in Guangzhou City using the descriptive statistical method. The results indicate that private cars are the main commuting mode, followed by public transport. Meanwhile, middle-class residents mainly undertake medium-short time and medium- short distance commuting. The study subsequently uses multilevel logistic regression and multiple linear regression models to analyze the factors that influence commuting mode choice, time and distance. The gender, age, number of family cars, housing source and jobs-housing balance are the most important factors influencing commuting mode choice; housing, population density, jobs-housing balance and commuting mode significantly affect commuting time; and transport accessibility, jobs-housing balance and commuting mode are the notable factors affecting commuting distance. Finally, this paper analyzes what is affecting the commuting activities of middle-class residents and determines the differences in commuting activity characteristics and influence factors between middle-class and ordinary residents. Policy suggestions to improve urban planning and urban management are also proposed. [ABSTRACT FROM AUTHOR]

The COVID-19 outbreak emerged in Wuhan, China, and was declared a global pandemic in March 2020. This study aimed to explore the association of daily mean temperature with the daily counts of COVID-19 cases in Beijing, Shanghai, Guangzhou, and Shenzhen, China. Data on daily confirmed cases of COVID-19 and daily mean temperatures were retrieved from the 4 first-tier cities in China. Distributed lag nonlinear models (DLNMs) were used to assess the association between daily mean temperature and the daily cases of COVID-19 during the study period. After controlling for the imported risk index and long-term trends, the distributed lag nonlinear model showed that there were nonlinear and lag relationships. The daily cumulative relative risk decreased for every 1.0 °C change in temperature in Shanghai, Guangzhou, and Shenzhen. However, the cumulative relative risk increased with a daily mean temperature below − 3 °C in Beijing and then decreased. Moreover, the delayed effects of lower temperatures mostly occurred within 6–7 days of exposure. There was a negative correlation between the cumulative relative risk of COVID-19 incidence and temperature, especially when the temperature was higher than − 3 °C. The conclusions from this paper will help government and health regulators in these cities take prevention and protection measures to address the COVID-19 crisis and the possible collapse of the health system in the future. [ABSTRACT FROM AUTHOR]

Cities face many challenging environmental problems that affect human well-being. Environmental risks can be reduced by Urban Green Infrastructures (UGIs). The effects of UGIs on the urban environment have been widely studied, but less attention has been given to the public perception of these effects. This paper presents the results of a study in Guangzhou, China, on UGI users’ perceptions of these effects and their relationship with sociodemographic variables. A questionnaire survey was conducted in four public green spaces. Descriptive statistics, a binary logistic regression model and cross-tabulation analysis were applied on the data from 396 valid questionnaires. The results show that UGI users were more concerned about poor air quality and high temperature than about flooding events. Their awareness of environmental risks was partly in accordance with official records. Regarding the perception of the impacts of environmental risks on human well-being, elderly and female respondents with higher education levels were the most sensitive to these impacts. The respondents’ perceptions of these impacts differed among the different green spaces. The effects of UGIs were well perceived and directly observed by the UGI users, but were not significantly influenced by most sociodemographic variables. Moreover, tourists had a lower perception of the impacts of environmental risks and the effects of UGI than residents did. This study provides strong support for UGIs as an effective tool to mitigate environmental risks. Local governments should consider the role of UGIs in environmental risk mitigation and human well-being with regard to urban planning and policy making. [ABSTRACT FROM AUTHOR]

This paper proposes an innovative cellular automata model based on the Harris Hawk Optimization (HHO) algorithm. HHO is an intelligent optimization algorithm inspired by the cooperative hunting behavior of Harris’s hawks, demonstrating excellent optimization efficiency in spatial searches. Combining the HHO algorithm with the CA model, we establish the HHO-CA model for simulating urban growth in Guangzhou, China. The simulation achieves a total accuracy of 91.95%, an accuracy of urban cells of 82.43%, and a Kappa coefficient of 0.7441, all superior to the Null model. Furthermore, comparing the HHO-CA model with other representative CA models, the HHO-CA model outperforms in total accuracy, accuracy of urban cells, and Kappa coefficient, showcasing significant advantages in using the HHO algorithm to mine transition rules during the simulation of urban growth processes. [ABSTRACT FROM AUTHOR]

Hepatitis B virus (HBV) infection is highly prevalent in Guangzhou, China. This study aimed to examine the long-term trend of HB incidence from 2008 to 2022 and the independent impacts of age, period, and cohort on the trends. HBV data were collected from the China Information System for Disease Control and Prevention. Joinpoint regression was utilized to examine temporal trends, and an age-period-cohort model was employed to estimate the effects of age, period, and cohort. A total of 327,585 HBV cases were included in this study. The incidence of chronic and acute HB showed a decreasing trend in Guangzhou over the past 15 years, with an average annual percent change of − 4.31% and − 16.87%, respectively. Age, period, and cohort all exerted significant effects. The incidence of HB was higher in males than in females and non-central areas compared to central areas. Age groups of 0–4 years and 15–24 years were identified as high-risk groups. The period relative risks for chronic HB incidence decreased initially and then stabilized. Cohorts born later had lower risks. Chronic HB incidences remain high in Guangzhou, especially among males, younger individuals, and residents of non-central areas. More efforts are still needed to achieve hepatitis elimination targets. [ABSTRACT FROM AUTHOR]

Livability is pivotal when planning human habitations. Sustainable planning strategies have been gradually adopted to enhance the livability of built environments, especially in the context of developing countries with a continuously improving planning system. Unlike other spontaneously developed low-income housing estates (e.g., urban villages) in China, subsidized housing estates (SHEs) are entirely planned and dictated by local governments and that may be significantly affected by urban planning policies and practices. However, the role of urban planning in achieving the livability of SHEs has yet to be fully investigated. By focusing on a pilot project of SHEs in Guangzhou, this study attempts to identify the extent and rationale of planning impacts on the livability of the SHEs. The study concludes that, although the updated planning policies and schemes encouraged public participation and livability, their achievements still hinged on the institutional environment in Socialist Marketized China. Consequently, the implementation of SHE plans encountered several challenges, resulting in insignificant improvements in livability from planning. This study provides an in-depth understanding of urban planning and its impacts on livability in the context of developing countries with a continuously developing planning system. [ABSTRACT FROM AUTHOR]

In the construction project of composite stratum in the Guangzhou subway tunnel, the frequent occurrence of chordal eccentric wear of disk cutters has become a major problem restricting the smooth progress of the project. According to the disk cutter rock breaking mechanism, the wear morphology of the chordal eccentric wear disk cutter, the mechanical properties of the cutter ring material, the chemical element composition, and the observation of metallographic structure were comprehensively analyzed, and the causes of the chordal eccentric wear of the cutter were determined in combination with maintenance methods. The results of the mechanical property test show that the chemical element composition of the cutter ring material complies with the 4Cr5MoSiV1 steel standard and also has high hardness and good toughness. The metallographic structure is fine and is not prone to brittle fracture and overload. On this basis, combined with the cutter maintenance report, it is determined that the reason for the occurrence of chordal eccentric wear caused by the non-rotation of the disk cutter is the mismatch between the setting of starting torque and the excavation parameters. According to the critical condition for chordal eccentric wear of the cutter, some suggestions are put forward for the adjustment of the tunneling parameters to avoid the occurrence of chordal eccentric wear disk cutter during excavation. [ABSTRACT FROM AUTHOR]

This study aims to investigate the impact of digital capabilities on business model innovation, and emphasizes the pivotal mediating role of dynamic capabilities, comprising sensing, seizing, and reconfiguring resources, in translating digital strengths into innovative business models. And also uncovers a nuanced perspective on organizational inertia, showcasing its potential to positively moderate the relationship between digital capabilities and business model innovation. A questionnaire-based, time-lagged study with a 1-week interval. From January 2023 to March 2023, we collected a total of 262 questionnaires from entrepreneurs located in the Pearl River-West River Economic Belt, such as Guangzhou and Nanning, China. To analyse the moderation and mediation model, we utilized The PROCESS Model 5. Digital capabilities have a positive impact on the innovation of enterprises' business models. Moreover, the connection between digital capabilities and business model innovation is mediated by dynamic capability. The findings also illustrate that organisational inertia moderates the relationship between digital capabilities and business model innovation. This study contributes to the existing literature on enterprise sustainable development by shedding light on the mediating and moderating mechanisms through which digital capabilities enhance business model innovation in enterprises. These findings offer valuable insights for enterprises aiming to thrive in dynamic markets, emphasizing the importance of a balanced approach to digital innovation, and instrumental for entrepreneurs seeking to refine their organisational strategies, particularly by bolstering their digital capabilities. [ABSTRACT FROM AUTHOR]

Water conservation is critical under the current state of climate change and population growth; however, water-conservation programs and research in China have generally focused on technological rather than behavioral innovations. This paper focuses on the state of water-conservation behavior and water education in China to assess how education, particularly the 9-year compulsory education program, affects water-conservation behavior. A survey (237 participants) was conducted in Guangzhou, the third largest city in China, to determine the attitudes of citizens towards conserving water. Overall, the following observations were made: (1) although 95 % of the participants were aware of water conservation, only 42 % recognized that it is urgently needed; (2) water-conservation actions lag behind water-conservation awareness, and only 19 % of the participants were willing to perform more than five actions, including daily water reuse and conservation, whereas 48 % of the participants performed less than two actions; (3) additional education will result in improved water-conservation behavior; (4) more than half of the participants who had graduated from primary and secondary schools showed poor water-conservation behavior; and (5) water-conservation education in the 9-year compulsory education program was extremely rare (representing 0.2-1.4 % of the curriculum) and only included in four compulsory courses. From these observations, it was concluded that water education seriously lags behind the economic development of Guangzhou. Water and environmental education should be emphasized in the 9-year compulsory education curriculum because this program has a relatively large number of students in China. [ABSTRACT FROM AUTHOR]

Authigenic carbonates from a landfill leachate collection system (LCS) resulting from early diagenesis mediated by microbes, are unique archives of the biogeochemical processes and environmental conditions inducing the carbonate formation. This paper reports the results of mineralogical, petrological, and geochemical studies of the carbonates collected from the LCS of Huoshaogang landfill in Guangzhou, China. The carbonates from the LCS pipes and the equalization basins occurred as laminated crusts and porous precipitates, respectively. The authigenic minerals consist mainly of low- and high-Mg calcites. Sedimentary fabrics likely linked with microbial metabolism are developed, including stromatolites, ooids, clots, peloids, botryoidal cements, and framboidal pyrites. In addition, putative microbial textures, including spheres, filaments, and rods, are preserved in the carbonates. The δC and δO values of the carbonates range from +7.34 to +18.21 ‰ and from −8.64 to −4.76 ‰ (V-PDB), respectively, indicating that the carbon is derived mainly from the residual CO after methanogenesis, and the oxygen is predominantly from meteoric waters. The Ce/Ce* values of carbonate phases revised by eliminating La effects demonstrate no or positive Ce anomalies, suggesting that the carbonates were precipitated in a reducing environment. The bacterial degradation of waste organic matter to CH and CO would significantly increase the alkalinity and pH of leachate and decrease the content of SO, and thus promote calcite crystal nucleation on the surface of microbial cells and subsequent precipitation under reducing conditions. The occurrence of high-Mg calcite precipitating later with incremental δC values implies the increasing trend of Mg/Ca ratios and δC values of dissolved inorganic carbon in the leachate during stabilization of the closed landfill. [ABSTRACT FROM AUTHOR]

This study assessed the regional differences of PM2.5 (fine particulate matter) concentration and secondary components in China. Through chemical analysis (Thermal/Optical Carbon Analyzer and ion chromatography) and statistical tools (SPSS and Origin software), PM2.5 samples' concentration and main components were estimated and compared in Tianjin and Guangzhou in December 2016. The average PM2.5 mass concentration was 148 μg/m3 in Tianjin and 62 μg/m3 in Guangzhou, indicating heavy air pollution in both cities. Organic carbon constituted 15% of PM2.5 in Tianjin, while that accounted for 25% in Guangzhou. The concentration of the secondary organic carbon accounted for 40% and 33% of organic carbon in Tianjin and Guangzhou, respectively. The ionic components in Tianjin made up 49% of PM2.5, while those of Guangzhou were responsible for 36% locally. The sulfate oxidation ratio reached 0.41 in Tianjin and 0.53 in Guangzhou while the nitrate oxidation ratio was 0.23 and 0.14 in the two cities, respectively. These results indicated high secondary conversion rate in PM2.5 pollution in both cities and suggested that PM2.5 mass concentration could not fully reflect its environmental and health effects, and so more attentions should be paid to the effects of its components, especially secondary components. In addition, the results could provide a scientific basis for making policies concerning air pollution control and developing strategies of air quality improvement. [ABSTRACT FROM AUTHOR]

The formation of decorative patterns on export porcelain has risen to the research dimension of cross-regional culture. The interplay between social elements and the formal evolution of export porcelain bowls from the Qing Dynasty in Guangzhou remains nebulous. This study elucidates these underlying cultural dynamics through the lenses of utility and societal implications, thus addressing how societal components contribute to the molding of tangible cultural heritage. Key findings include: (1) A dominance of the ring-foot design in the bases of Qing Dynasty export bowls; (2) The diameter and height of the Qing Dynasty export bowls show relatively concentrated characteristics, reflecting a systemic production trend and relative consistency in form; (3) Some of the Qing Dynasty bowls exceed the parameter range of typical tableware, reflecting the adaptability and innovation of production mechanisms in responding to special market demands. The morphological evolution of the Qing Dynasty export bowls is a true reflection of the interweaving of multiple factors such as comfort design and aesthetic preferences, while the uniformity in shape is a comprehensive reflection of meeting market demands and advances in production technology. This study extends the research dimension to the interaction between standardized production techniques and socio-cultural demands. [ABSTRACT FROM AUTHOR]

Place branding has become a popular strategy to promote place visibility and place image communication and gains attention in the field of city planning, geography, and place management. The contribution of geographical knowledge has been emphasized and discussed in recent place branding studies, including the role of geographical scale in branding strategies and management. However, current research mainly places the issues of scale from the top-down perspective of branding governance, and the bottom-up processes based on local culture and embodied experiences are overlooked. Drawing on participatory-based visual methodology, in the article, a combination of self‐directed photography, photo evaluation, eye-tracking experiment, and interview are employed to the scale transformation performance of place brands from the perspective of embodied experience. Taking Xinhepu in Guangzhou, China as a case study, the results show that both residents and nonresidents do not limit their perception of the Xinhepu brand to a microscale space but point to the city of Guangzhou. Specifically, the process of scale transformation of place brands is characterized by the interaction of temporal and spatial factors that provide possibilities for scale transformation. The physical landscape in space plays a role in place branding, while in time scale, Xinhepu connects Guangzhou's past and present and is a microcosm of the city's image and historical development; thus, in people's embodied perception, Xinhepu can be transformed into a city brand through place culture creation. The article can provide a new explanation for the construction of place branding at multiple geographical scales and explore how the body's unconscious, nonrepresentational rhythms play a role in place brand scale transformation. [ABSTRACT FROM AUTHOR]

By focusing on Guangzhou, this paper examines how different concepts of city in terms of urban-rural relationships are shaped in transforming China since 1949, and explores how they influence the way in which urban planning are practiced. In the pre-reform era, the city was defined as a productive space under the system of urban-rural segregation established for securing rapid industrialization. Urban planning was thus only concerned with the development of urban areas. In the 1980s and 1990s after the reform, institutional change and economic transformation mobilized the urban-rural linkages. The development of suburban areas was then considered by urban planning, but this consideration was a passive response to urban problems such as population explosion and water resources protection. Since the new millennium, the agenda for sustainable development and problems of uneven urban-rural development have called for the development of urban-rural integration. In this context, the city is conceptualized as a complex of mountain, city, river, farmland and sea, reconstructing the ideology of urban-rural division in defining urban development. Urban planning has therefore sought in an active way to develop a sustainable city embracing rural and natural elements, and to balance economic growth and environmental protection. It is argued that developing the concept of city as a complex of urban and rural elements contributes to the urban planning for sustainable urban development, while this conceptualization relies on the recognition of the integrated urban-rural relationship. [ABSTRACT FROM AUTHOR]

Metropolitan cities in China are commonly confronted with unresolved traffic congestion issues, primarily due to rapidly increasing traffic demand. Group disparity between commuting mode choice and its spatial distribution on road networks has enabled us to examine the factors that give rise to the discrepancies and the fundamental spatial causes of traffic congestion. In recent years, micro-perspective, individual, and behavior-based spatial analysis have mushroomed and been facilitated with effective tools such as temporal geographic information systems (T-GIS). It is difficult to study the interrelations between transport and space on the basis of commuting mode choice since the mode choice data are invisible in a specific space such as a particular road network. Therefore, in the field of transport, the classical origin destination (OD) four-stage model (FSM) is usually employed to calculate data when studying commuting mode choice. Based on the relative principles of T-GIS and the platform of ArcGIS, this paper considers Guangzhou as a case study and develops a spatio-temporal tool to examine the daily activities of residents. Meanwhile, the traffic volume distribution in rush hours, which was analyzed according to commuting modes and how they were reflected in the road network, was scrutinized with data extracted from travel diaries. Moreover, efforts were made to explain the relationship between traffic demand and urban spatial structure. Based on the investigation, this research indicates that traffic volumes in divergent groups and on the road networks is driven by: 1) the socio-economic characteristics of travelers; 2) a jobs-housing imbalance under suburbanization; 3) differences in the spatial supply of transport modes; 4) the remains of the Danwei (work unit) system and market development in China; and 5) the transition of urban spatial structure and other factors. [ABSTRACT FROM AUTHOR]

The emission of platinum group elements (PGE) from automobile catalytic converters has led to enrichment of PGE in road dusts and roadside soils in urban areas that are well above the natural background levels. This paper evaluates the source of contamination of all the PGE and Au in road dusts and roadside soils in the Pearl River Delta region, including three major cities, Shenzhen, Guangzhou and Hong Kong, South China. Samples were digested using Carius tube and analyzed by isotope dilution ICP-MS; Os was separated by distillation and other PGE by Te-coprecipitation. All samples have elevated PGE concentrations above the background values of uncontaminated soils and contain higher Pt, Pd and Rh than other PGE. The maximum values are 181 ng/g Pt, 514 ng/g Pd, 53 ng/g Rh and 1345 ng/g Au. There are clear positive correlations between Pt and Pd, Pt and Rh, and Pd and Rh, indicating that the main emitted of PGE from automobile catalyst are Pt, Pd and Rh. High concentrations of Au were also found in road dust samples from Hong Kong and Shenzhen. Dust samples with higher Os contents have lower Os/Os ratios. Samples from Hong Kong show relatively high Pt/Rh ratios. Positive correlations between Pt and Ru, and Pt and Ir were found in Shenzhen and Hong Kong, but only positive correlations between Pt and Ir were found in Guangzhou. These different characteristics reflect different automobile catalytic systems used in Hong Kong and mainland China. [ABSTRACT FROM AUTHOR]

Accurate knowledge of the quality and environmental impact of the highway runoff in Pear River Delta, South China is required to assess this important non-point pollution source. This paper presents the quality characterization and environmental impact assessment of rainfall runoff from highways in urban and rural area of Guangzhou, the largest city of Pear River Delta over 1 year’s investigation. Multiple regression and Pearson correlation analysis were used to determine influence of the rainfall characteristics on water quality and correlations among the constituents in highway runoff. The results and analysis indicates that the runoff water is nearly neutral with low biodegradability. Oil and grease (O&G), suspended solids (SS) and heavy metals are the dominant pollutants in contrast to the low level of nutrient constituents in runoff. Quality of highway runoff at rural site is better than that of at urban site for most constituents. Depth and antecedent dry period are the main rainfall factors influencing quality of highway runoff. The correlation patterns among constituents in highway runoff at urban site are consistent with their dominant phases in water. Strong correlations ( r ≥ 0.80) are found among chemical oxygen demand (COD), total phosphorus, Cu and Zn as well as conductivity, nitrate nitrogen and total nitrogen. O&G, COD, SS and Pb in highway runoff at urban site substantially exceed their concentrations in receiving water of Pear River. The soil directly discharged by highway runoff at rural site has contaminated seriously by heavy metals in surface layer accompanying with pH conversion from original acidic to alkaline at present. [ABSTRACT FROM AUTHOR]

This paper reports the results from a study of the organic composition of rainwater collected at Tianhe district of Guangzhou city, P.R. China, during the dry season. Several special setups of a pyrex bottle with a glass funnel were used for the collection of the rainwater. Three fractions (aliphatics, PAHs and fatty acids) were separated from the total extracted organic compounds and identified with GC-MS. The molecular diagnostic ratios were utilized for the source reconciliation. The aliphatic hydrocarbon and the biomarkers (triterpanes and steranes) distribution show a characteristic of the petrochemical source in the rainwater samples. The PAHs diagnostic ratios [e.g. MP/P, MPI, Fl/ (Fl + Py)] indicated vehicular emissions. The fatty acids ratios (e.g. C18:1/C18:0 and C18:2/C18:0) reflect the contribution of cooking emissions, while the higher plant waxes play little part. Moreover, the values of MP/P, MPI, BaA/(BaA + CT) and BeP/(BeP + BaP) reflected the origin of the long-distance transportation to some extent. On the whole, for the dry season rainwater, all molecular diagnostic ratios indicated the complexity of the organic composition of the rain, which have the characteristics of both a local emission contribution and a long-distance transportation contribution. [ABSTRACT FROM AUTHOR]

Environmental pollution from industrialization, urbanization and agriculture is a serious issue facing all countries during economic development. The Pearl River Delta in Southern China offers a unique case for study and documentation on the ecosystem changes during the fast economic development and urbanization over the past 40 years. This collection of papers from a conference on marine coastal pollution and ecotoxicology held in Guangzhou of China provide the current status on the environmental and ecological processes from the intensive urbanization and development. The research information available from this special issue can be used for both a comparison over time and with other locations and countries, and, in addition, for policy making to serve the long-term sustainable development of the region and the world. [ABSTRACT FROM AUTHOR]

Intra-family conflict had an adverse effect on adolescent mental health problems. However, to date, few studies using the longitudinal-design have examined the underlying mechanism of this relationship. Therefore, the purpose of the current study was to extend previous study from a longitudinal perspective, and further explore the mediating role of sleep quality that were shown to underlie these relationships. Data came from a longitudinal survey of 932 adolescents (54.0% female; mean of age at baseline = 13.25 years, SD = 0.66). The adolescents were recruited from two junior high school in Guangzhou city, China. A battery of standardized measures was used to assess intra-family conflict, sleep quality, internalizing symptoms and externalizing symptoms for three times with an interval of one year. After adjusting for family demographics, sleep quality at T1 and mental health problems at T1, T1 intra-family conflict had significant effects on sleep quality at T2, and T2 sleep quality mediated the association between T1 intra-family and mental health problems at T3. In addition, this mediation of sleep quality was consistent across gender. Sleep quality was an important mediator in explaining the relationship between intra-family conflict and mental health problems in adolescents. Prevention and intervention programs aimed at improving their sleep quality may be critical to prevent mental health problems when adolescents are involved in family conflict. [ABSTRACT FROM AUTHOR]

The presence of Africans in Chinese cities has made their healthcare-related issues an expanding area of interest. However, previous studies have not thoroughly explored how Africans live through health problems. This article explores the taken for granted aspect using the analytical frameworks of migration as a social determinant of health and phenomenological sociology. Based on interviews with 37 Nigerians in Guangzhou city, it describes how health and illnesses are lived and the ways that language barrier, cost of health care, immigration status and racism and discrimination intertwine with quotidian occurrences to shape the experiences of health challenges. Migrant networks and community structure provided critical assistance, but the context of labour circumstances and undocumentedness can overstretch these critical sources of support. The article exposes how the broader context of being and living in China determine how Africans experience health challenges in Chinese cities. [ABSTRACT FROM AUTHOR]

Air pollution prevention and control is an important way to eliminate haze, and air quality prediction can provide predictive information for air pollution prevention and people's health. Therefore, it is of great practical usefulness to establish a scientific and effective air quality prediction model. Combined forecasting is a popular statistical method for air pollution forecasting, which generally includes two steps of individual model selection and weight determination. This research introduces LASSO for individual models selection, and ELM to establish a nonlinear combined forecasting model, named CEEMD-LASSO-ELM. LASSO can not only select individual models, but also avoids the possible collinearity between the selected individual models. Daily air quality index (AQI) series of Guangzhou, Kunming, Lanzhou and Hulunbuir are selected to verify the feasibility and effectiveness of the proposed CEEMD-LASSO-ELM model. Combined with CEEMD, seven comparative models are Random-ELM, Rank-ELM, Random-LR, Rank-LR, LASSO-GRNN, LASSO-PSOGSASVR and LASSO-LR. The data analysis shows that the proposed CEEMD-LASSO-ELM model has better prediction accuracy and stronger generalization ability. Taking Lanzhou as an example, the MAPE of CEEMD-LASSO-ELM model is 1.813% lower than that of the seven comparative models on average. [ABSTRACT FROM AUTHOR]

Based on survey data conducted in Guangzhou in 2021, this study employs canonical correlation analysis (CCA) to evaluate the relationship between neighborhood green space, residents' green space use behavior, and their mental health. The results show that compared with the objectively measured accessibility, residents' subjective perceived accessibility of neighborhood green space plays a greater role in promoting green space use behavior and mental health. Meanwhile, the plant diversity, safety, and the number of recreational facilities in a green space can promote the frequency of green space use, improve residents' mental health status and reduce their perceived stress. Although perceived accessibility is more related to green space use behavior than green space quality indicators, green space safety and recreational facilities have many more benefits on mental health than perceived accessibility. In addition, residents' green space use behavior, especially green space visit frequency, can promote mental health and reduce perceived stress. [ABSTRACT FROM AUTHOR]

Abstract. As a novel type of industrial establishment in the era of globalization, foreign direct investment (FDI) has become a new driving force in the shaping of urban structure. To understand the current worldwide urban restructuring process, the location behaviour of FDI firms should be fully investigated. But few empirical studies on industrial location have been carried out at the intrametropolitan scale, probably due to the lack of disaggregated data and appropriate models. This study geo-references FDI firms by their postal codes and captures site attributes through cross-referencing firm distribution with other spatial coverage such as population statistics, land uses, and designated development zones. This paper argues for a Poisson and negative binomial model of firm location based on count-data and tests such a firm location model using the case of metropolitan Guangzhou, PRC. Results, in contrast to previous studies at the national and regional scales of this country, confirm that, at least statistically, intra-urban FDI firm location in the context of a transitional economy presents regularities that are explainable according to 'rational' economic considerations of site suitability. [ABSTRACT FROM AUTHOR]