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With the application of intergenerational theory as its analytical framework, this paper seeks to provide new insights into the social construction of sugar-sweetened food and food practices in the context of contemporary urban China, drawing on 16 months' in-depth qualitative research in the city of Chongqing. From an intergenerational perspective, it argues that although adults and children both typically construct sugar-sweetened food as "bad" for health based on the logic of its biological meaning, there are more generational differences in the understandings of sociocultural meanings associated with these foods, which are the main reasons may lead to intergenerational conflict. Caregivers tend to regard their control of children's sugar-sweetened food intake as a means to discipline their children's bodies and develop food moralities. However, children themselves are likely to perform sugar-sweetened food practices as a way of socializing and sometimes resisting the control of caregivers. Based on this, this paper further shows that these diverse views are rooted in the tension between caregivers' anxiety about the transmission of food moralities through intensive parenting practices and children's agency in food consumption in contemporary urban China. These findings enhance intergenerational-theoretical research and highlight the need to move beyond the analytical framework of "behaviour change" in related food and health studies. [ABSTRACT FROM AUTHOR]

This paper utilizes an improved undesirable output DEA model to measure the eco-efficiency of cities in five major urban agglomerations in China during 2006–2020. It employs the Theil Index and Geodetector to investigate the spatial-temporal distribution differentiation characteristics and driving factors of urban eco-efficiency. The main findings are as follows. Firstly, the eco-efficiency of all urban agglomerations showed a fluctuating upward trend, but the eco-efficiency performance of different urban agglomerations in China shows a stratification characteristic. Specifically, the Pearl River Delta urban agglomeration consistently ranks first in China, while the mean values of the Yangtze River Delta urban agglomeration, Beijing-Tianjin-Hebei urban agglomeration, and Chengdu-Chongqing urban agglomeration are lower than the national average. Secondly, the overall differences in the urban eco-efficiency of all sample cities show a consistently fluctuating downward trend. The factor that affects the level differences of eco-efficiency in different cities is the intra-regional differences. Last but not least, the top three factors affecting the spatial distribution difference of urban eco-efficiency in the whole sample are environmental pollution control investments, innovation level, and environmental infrastructure investments. In the end, this paper proposes that reducing the intra-regional differences is the primary task to achieve the coordinated improvement of urban eco-efficiency in urban agglomerations, and then puts forward some policy suggestions to improve eco-efficiency for the five major urban agglomerations. [ABSTRACT FROM AUTHOR]

Critical scholarly attention to vertical urbanism has expanded greatly in recent years but has seldom engaged with the variety of high-rise urban forms developed in mainland Chinese cities following the demise of socialist urban political economy. This paper introduces the case study of Chongqing as a critical example of the cultural significance of vertical urbanism in the post-socialist Chinese city, examining how supposedly 'weird' spaces of vertical density are materially and discursively constructed. Chongqing has undergone rapid urban expansion since the 1990s within a narrow and mountainous terrain, resulting in a number of extraordinary instances of extreme vertical density in the city. These sites have subsequently become 'spectacles' in themselves, widely photographed and discussed on social media. This paper surveys online discourse and imaging of these sites to categorise them as examples of connection, compression and luxification. Verticality is used to construct imaginaries of urban futures, and designations of 'weird' verticality differ between outsiders and locals. Such imaginaries may also obscure the history of urban restructuring which gave rise to these spaces in the first instance, and the conflicts between public and private space which emerge from this restructuring. The example of Chongqing provides an important demonstration of verticality as an everyday, historically grounded and contested environment within the city, rather than a recent imposition on a residual horizontal way of life. This paper concludes with a call for greater ethnographic attention to the weird qualities of such vertical spaces in the production of new urban theory. [ABSTRACT FROM AUTHOR]

This paper focuses on the cardinality constrained mean-variance portfolio optimization, in which only a small number of assets are invested. We first treat the covariance matrix of asset returns as a diagonal matrix with a special matrix processing technique. Using the dual theory, we formulate the lower bound problem of the original problem as a max-min optimization. For the inner minimization problem with the cardinality constraint, we obtain its analytical solution for the portfolio weights. Then, the lower bound problem turns out to be a simple concave optimization with respect to the Lagrangian multipliers. Thus, the interval split method and the supergradient method are developed to solve it. Based on the precise lower bound, the depth-first branch and bound method are designed to find the global optimal investment selection strategy. Compared with other lower bounds and the current popular mixed integer programming solvers, such as CPLEX and SCIP, the numerical experiments show that our method has a high searching efficiency. History: Accepted by Pascal Van Hentenryck, Area Editor for Computational Modeling: Methods & Analysis. Funding: This work was supported by the National Natural Science Foundation of China [Grants 12101317, 12271071, and 11991024], the Natural Science Foundation of Jiangsu Province [Grant BK20200819], the Team Project of Innovation Leading Talent in Chongqing [Grant CQYC20210309536], the Contract System Project of Chongqing Talent Plan [Grant cstc2022ycjh-bgzxm0147], and the Philosophy and Social Science Fund of Education Department of Jiangsu Province [Grant 2020SJA0168]. K.F.C. Yiu is supported in part by the Research Grants Council of Hong Hong [Grant PolyU 15223419], the Hong Kong Polytechnic University [Grants 4-ZZPT and 1-WZ0E], and the Research Centre for Quantitative Finance [Grant 1-CE03]. Supplemental Material: The software that supports the findings of this study is available within the paper and its Supplemental Information (https://pubsonline.informs.org/doi/suppl/10.1287/ijoc.2022.0344) as well as from the IJOC GitHub software repository (https://github.com/INFORMSJoC/2022.0344). The complete IJOC Software and Data Repository is available at https://informsjoc.github.io/. [ABSTRACT FROM AUTHOR]

Rainstorm is one of the global meteorological disasters that threaten the safety of transportation infrastructure and the connectivity of transportation system. Aiming to support the resilience assessment of transportation infrastructure in three representative regions: Sichuan–Chongqing, Yangtze River Delta, and Beijing-Tianjin-Hebei-Shandong, rainfall data over 40 years in the three regions are collected, and the temporal distribution of rainfall are analyzed. Prediction equations of rainfall are established. For the purpose of this, the probabilistic density function (PDF) is assigned to the rainfall by fitting the frequency distribution histogram. Using the assigned PDF, the rainfall data are transformed into standard normal space where regression of prediction equations is performed and the prediction accuracy is tested. The results show that: (1) The frequency of rainfall in the three regions follows a lognormal distribution based on which the prediction equations of rainfall can be established in standard normal space. The error of regression shows no remarkable dependence on self-variables, and the significance analysis indicates that the equations proposed in this paper are plausible for predicting rainfalls for the three regions. (2) The Yangtze River Delta region has a higher risk of rainstorm disaster compared to the other two regions according to the frequency of rainfall and the return period of precipitation concentration. (3) Over the period of 1980–2021, the Sichuan–Chongqing region witnessed an increase in yearly rainfall but a decrease in rainstorm disasters, whereas the other two regions experienced a consistent rise in both metrics. [ABSTRACT FROM AUTHOR]

Wildfires cause great losses to the ecological environment, economy, and people's safety and belongings. As a result, it is crucial to establish wildfire susceptibility models and delineate fire risk levels. It has been proven that the use of remote sensing data, such as meteorological and topographical data, can effectively predict and evaluate wildfire susceptibility. Accordingly, this paper converts meteorological and topographical data into fire-influencing factor raster maps for wildfire susceptibility prediction. The continuous convolutional neural network (CCNN for short) based on coordinate attention (CA for short) can aggregate different location information into channels of the network so as to enhance the feature expression ability; moreover, for different patches with different resolutions, the improved CCNN model does not need to change the structural parameters of the network, which improves the flexibility of the network application in different forest areas. In order to reduce the annotation of training samples, we adopt an active learning method to learn positive features by selecting high-confidence samples, which contributes to enhancing the discriminative ability of the network. We use fire probabilities output from the model to evaluate fire risk levels and generate the fire susceptibility map. Taking Chongqing Municipality in China as an example, the experimental results show that the CA-based CCNN model has a better classification performance; the accuracy reaches 91.7%, and AUC reaches 0.9487, which is 5.1% and 2.09% higher than the optimal comparative method, respectively. Furthermore, if an accuracy of about 86% is desired, our method only requires 50% of labeled samples and thus saves about 20% and 40% of the labeling efforts compared to the other two methods, respectively. Ultimately, the proposed model achieves the balance of high prediction accuracy and low annotation cost and is more helpful in classifying fire high warning zones and fire-free zones. [ABSTRACT FROM AUTHOR]

This paper explores the impact of the political hierarchies of cities in China from different perspectives. First, we examine the economic disparities between prefectural cities and municipalities. Furthermore, this paper draws upon a quasi‐ experiment to analyze the impact of upgrading Chongqing to a municipality in 1997 using the synthetic control method. The city‐upgrading policy significantly increased Chongqing's gross domestic product (GDP) in the following 4 years. Finally, we find that the policy increased GDP in treated cities within 1200 km of Chongqing by about 10%–13% relative to the control cities. [ABSTRACT FROM AUTHOR]

Scientific and technological innovation and the sustainable development of new urbanization are the key factors to promote national economic growth, and have a very important role in promoting regional development and international competitiveness. Based on the panel data of 16 cities in Chengdu-Chongqing dual-city economic circle from 2015 to 2022, this paper uses entropy weight method to determine the weight of each index and constructs a coupling coordination model to explore the sustainable development of scientific and technological innovation and new urbanization, the Panel Vector Autoregression (PVAR) model was used to further verify the interaction between the two. The empirical results show that the coupling coordination degree of scientific and technological innovation and new urbanization in Chengdu-Chongqing economic circle is increasing year by year. There is a balanced relationship between scientific and technological innovation and new urbanization, and the two are two-way Granger causality. Therefore, the conclusion puts forward the practical enlightenment of increasing investment in scientific and technological innovation, guiding enterprises to carry out scientific and technological innovation to feedback new urbanization and accelerate the construction of new urbanization, and actively integrating with urban development. [ABSTRACT FROM AUTHOR]

A new Chengyuchelys latimarginalis (Xinjiangchelyidae) specimen is reported based on a well-preserved, nearly complete shell from the upper part of the Upper Jurassic Shangshaximiao Formation of Qijiang District, Chongqing Municipality, China. The Xinjiangchelyidae were widely distributed in Asia during the Jurassic and were the dominant turtle group in Asian freshwater ecosystems during the Late Jurassic. The Qijiang specimen adds a new element to the yet poorly known freshwater vertebrate fauna and extends the geographical distribution of C. latimarginalis. This paper discusses the intraspecific variation in C. latimarginalis for the first time. It provides a new insight for studying the evolution, habitat, and diversity of xinjiangchelyids. [ABSTRACT FROM AUTHOR]

Using data from the 2015 China Household Financial Survey (CHFS) this paper examines the effect of culture on the gender gap in financial literacy. We exploit geographical differences in culture in China, comparing outcomes between rural and urban areas and between areas in the east and west (Shanghai and Chongqing). Using the Blinder‐Oaxaca decomposition we show that, nationally, the gender gap in financial literacy is entirely the product of differences in the way men and women acquire financial literacy. It is a result consistent with cultural effects. When considering just women in Shanghai and Chongqing we observe a raw financial literacy differential of 13% (favoring Shanghai). This gap is also the product of differences in the way financial literacy is acquired. It provides additional evidence as to the importance of culture when it comes to understanding financial literacy. [ABSTRACT FROM AUTHOR]

In the Chengdu-Chongqing economic circle in China, the recommended bearing capacity of a medium-weathering mudstone foundation is less than the capacity of the rock structure to withstand loads. The aim of this paper was to perform plate loading tests (PLTs) with binocular vision measurement (BVM) to obtain the accurate deformation of the foundation under vertical loading. The results revealed that vertical load–bearing foundations have a failure mode that can be reduced to that of thrust failures for thin bedded structures of mudstone foundations. By analyzing the differences in results between the PLTs and the uniaxial compressive strength tests under the same conditions, a new formalism for calculating foundation-bearing capacity was proposed; there is only a 5% difference compared to in situ tests. The results of this research provide theoretical support and a practical benchmark for the full development of the load-bearing capability of soft red rocks. As the Chengdu-Chongqing economic circle progresses toward the international urban cluster, inevitably, soft rock is used as a foundation retaining layer in the construction of superhigh and super-rise buildings in the region. However, owing to antiquated testing methods and poor intelligibility of the testing equipment, the bearing capacity of such a mass of rock has yet to be fully developed and cannot meet the dual-carbon economic goals and sustainable development of architectural design. Based on this, the study introduces a noncontact method to measure the bearing capacity of soft rock within the traditional method of in situ testing and combines the concept of big data analysis to advance an empirical method for calculating the bearing capacity accurately. Based on the results of this study, the concept of natural foundations can be adopted and the engineering dilemma that the treatment of building foundations cannot be economical and practical can be solved. [ABSTRACT FROM AUTHOR]

A calamitous landslide happened at 22:00 on September 1, 2014 in the Yunyang area of Chongqing City, southwest China, enforcing the evacuation of 508 people and damaging 23 buildings. The landslide volume comprised 1.44 million m3 of material in the source area and 0.4 million m3 of shoveled material. The debris flow runout extended 400 m vertically and 1600 m horizontally. The Xianchi reservoir landslide event has been investigated as follows: (1) samples collected from the main body of landslide were carried out using GCTS ring shear apparatus; (2) the parameters of shear and pore water pressure have been measured; and (3) the post‐failure characteristics of landslide have been analyzed using the numerical simulation method. The excess pore‐water pressure and erosion in the motion path are considered to be the key reasons for the long‐runout motion and the scale‐up of landslides, such as that at Xianchi, were caused by the heavy rainfall. The aim of this paper is to acquired numerical parameters and the basic resistance model, which is beneficial to improve simulation accuracy for hazard assessment for similar to potentially dangerous hillslopes in China and elsewhere. [ABSTRACT FROM AUTHOR]

The high-quality development of service industry has become an important engine for promoting sustainable economic development. This paper first constructed the evaluation index system of high-quality development of service industry, based on panel data from 2005 to 2020. Second, Kernel density, Markov chain and Dagum Gini coefficient were used to represent the regional differences and dynamic evolution of service industry, and the Koo method was used to explore the characteristics of spatial agglomeration. Finally, social network analysis was used to identify core indicators. The study found that: (1) From 2005 to 2020, the overall level of service industry first decreases and then increases, with Chengdu and Chongqing leading other cities. (2) The development of service industry in the CCEC has large spatial differences, mainly due to inter-regional differences. (3) The level of spatial agglomeration is less variable, with high agglomeration mainly in Chengdu. (4) Indicators such as the level of human capital are the core factors of its high-quality development. This study is of great theoretical and practical significance for the optimization and upgrading of service industry in the CCEC and the synergetic development of the region. [ABSTRACT FROM AUTHOR]

Though road authorities have well-defined inspection protocols for evaluating bridge serviceability, gaps remain in understanding optimal timing and the impact of maintenance strategies on an individual bridge and its subsystems and, consequently, on the holistic performance of a road network. This paper proposes an innovative model based on system reliability principles that develops optimized bridge maintenance strategies aimed at enhancing the overall reliability of a bridge-dominated road network by considering the quantified impact of bridge component deterioration. Using the first-order second-moment method, we initially determine the reliability index for each bridge based on condition ratings derived from routine inspections as outlined in the bridge inspection manual. Advanced optimization algorithms then formulate the optimal maintenance strategies for the bridge structures. Finally, we gauge the system reliability of the network using Ditlevsen bounds approximation, considering the impact of maintenance actions on varied bridge structural components. The developed model was implemented on a typical bridge-dominated road network in Chongqing, China. The results demonstrate the model has the capacity to quantify the impact of diverse bridge maintenance strategies on the total road network, offering valuable insights for decision makers to design effective, efficient maintenance strategies aimed at extending the lifespan of bridge-dominated road networks. [ABSTRACT FROM AUTHOR]

Though road authorities have well-defined inspection protocols for evaluating bridge serviceability, gaps remain in understanding optimal timing and the impact of maintenance strategies on an individual bridge and its subsystems and, consequently, on the holistic performance of a road network. This paper proposes an innovative model based on system reliability principles that develops optimized bridge maintenance strategies aimed at enhancing the overall reliability of a bridge-dominated road network by considering the quantified impact of bridge component deterioration. Using the first-order second-moment method, we initially determine the reliability index for each bridge based on condition ratings derived from routine inspections as outlined in the bridge inspection manual. Advanced optimization algorithms then formulate the optimal maintenance strategies for the bridge structures. Finally, we gauge the system reliability of the network using Ditlevsen bounds approximation, considering the impact of maintenance actions on varied bridge structural components. The developed model was implemented on a typical bridge-dominated road network in Chongqing, China. The results demonstrate the model has the capacity to quantify the impact of diverse bridge maintenance strategies on the total road network, offering valuable insights for decision makers to design effective, efficient maintenance strategies aimed at extending the lifespan of bridge-dominated road networks. [ABSTRACT FROM AUTHOR]

The city of Chongqing in southwestern China has adopted a systematic set of urbanization policies since the late 2000s. Due to their emphasis on the role of the government and their scale, they deserve close attention. Yet, few studies have examined both positive and negative impacts of the urbanization policies regarding land acquisition, hukou conversion and urban housing as a complete process from rural migrants' perspective. More longer-term empirical studies focusing on rural migrants' reactions to the urbanization policies are needed. By conducting interviews with rural migrants, this paper aims to fill this gap. The results show that the migration intentions of rural migrants living in public rental housing are well-organized and purposive. The motivations for migration are not exclusively financial, but include the opportunities for better schooling and enhanced family bonds that come with living in public rental housing. Meanwhile, the institutional and social barriers faced by rural migrants were also identified. The goal of the paper is to enrich the understandings of the effects of urbanization policies in China. [ABSTRACT FROM AUTHOR]

Probabilistic seismic hazard analysis is an important scientific basis for building seismic fortification. Unlike most seismic hazard analyses starting from the perspective of magnitude, this paper presents a seismic hazard analysis method based on the monthly maximum peak ground acceleration (PGA) distribution. In this paper, cities of Chongqing, Chengdu, and Kunming in southwest China are taken as examples where historical earthquake events from 1920 to 2020 with surface wave magnitude (Ms) greater than or equal to 3 and epicentral distances within 400 km are selected for analysis. PGA data are back-calculated from Ms data recorded in the earthquake catalog using the attenuation relation of seismic parameters. By considering the monthly maximum PGA values of the three cities as statistical samples, regression analysis is performed to obtain the monthly maximum PGA distribution and the frequency-PGA relation respectively. Based on the Poisson model and the parameters obtained from the regression analysis, then seismic hazard analysis is conducted to derive year exceedance probability vs. PGA curves and recurrence interval vs. PGA curves. Finally, earthquake events with the epicentral distance within 200 km, 300 km, and 400 km are respectively analyzed to discuss the influence of the epicentral distance on results of seismic hazard analysis. [ABSTRACT FROM AUTHOR]

Background: In the global trend of actively promoting the participation of older adults in the digital age, the relevant negative issues featuring potential Internet Addiction (IA) among them has risen to be a new challenge facing the global public health. However, there is a severe lack of related research. This study aimed to gain a comprehensive understanding of the phenomenon and process of IA among the elderly. The purpose of this paper is to introduce factors that may influence IA in the demographic. Methods: This study employed qualitative descriptive research methods to investigate older adults' perceptions and experiences of IA. Semi-structured in-depth personal interviews were conducted between March and June 2023 with 36 senior citizens from urban communities in Chongqing, Southwest China. Data were analyzed via inductive content analysis methods. Results: Through data analysis, 2 main categories concerning IA in older adults were identified: risk factors and protective factors. The risk factor categories include 5 individual factors (e.g., Internet as the major avenue for pursuing personal hobbies and interests, etc.), 3 family factors (e.g., household WIFI increasing the risk of prolonged Internet use indoors, etc.), 2 peer factors (e.g., peer recommendation and guidance as catalysts for intensified Internet engagement, etc.), 2 socio-environmental factors (e.g., the widespread daily Internet use spurs offline intolerance, etc.), and 3 Internet platform factors (e.g., the plenitude of online content triggers endless viewing/browsing behaviors, etc.). The category of protective factors encompasses 2 individual factors (e.g., a higher level of perceived risk regarding internet health hazards, etc.) and 2 family factors (e.g., more family commitment, etc.). Conclusions: Older adults' Internet addictive behaviors are shaped by multiple and complex internal and external factors. A higher level of online health risk perception is a key protective factor to effectively avoid the occurrence and deterioration of IA among the aged, a distinct finding from this study. It is believed that the "individual-family-peer-community" synergy strategy is expected to become an essential direction for IA intervention for older adults, in order to promote healthy Internet use among older adults. [ABSTRACT FROM AUTHOR]

As immovable stone cultural heritage is kept in the open air, they are more susceptible to damage, and damage detection is very important for the protection and restoration of cultural heritage. This is especially true for gold-overlaid stone cultural heritage, which is usually more complicated than ordinary stone carvings. However, the detection of cultural heritage damages is mainly based on expert visual inspection, which is often subjective, time-consuming, and laborious. This paper uses the Mask R-CNN algorithm to rapidly and accurately detect the gold foil shedding of stone cultural heritage through two-dimensional images. The research data are from the high-precision images of the Dazu Thousand-Hand Bodhisattva Statue (World Heritage, UNESCO) in Chongqing, China. After cleaning and augmentation, 1900 images are input into Mask R-CNN model for training. Finally, the average precision value (AP) for detecting gold foil shedding is found to be 0.967. In order to test the performance of the model, the new images that do not participate in the training period are used, and it is found that the model can still accurately detect the gold foil shedding even if there are interference factors. This is the first attempt to detect the damages of gold-overlaid stone cultural heritage based on a deep learning algorithm, and it has achieved good results. [ABSTRACT FROM AUTHOR]

The literature on urban vitality tends to focus on the built environment. This paper argues that some important processes in shaping vitality may be overlooked without examining the intensity and diversity of economic and human activities. Using newly developed spatial big data and adopting the methods of multi-indicator measurement and spatial analysis methods, we analyzed the pattern of urban vitality in Chongqing, a provincial city in western China and, on this basis, evaluated the creation and maintenance of urban vitality from the economic and human activities perspective. Our findings indicate that the impacts of economic and human activities are positive and significant. Among the three intensity and diversity indicators, economic intensity and population density show an effect on urban vitality stronger than that of economic diversity. However, economic diversity has the strongest superposition or interactive effect, and is thus an important foundation dynamic. The positive effect of population density on urban vitality is largely a result of Chongqing's jobs-housing balance. The case of Chongqing highlights the importance of topographic features, historical inheritance, large-scale migration, and cultural activities in shaping the distinctive vitality pattern of a city. This study contends that the creation and maintenance of urban vitality can not be fully explained without incorporating the impacts of economic and human activities. It contributes to a comprehensive measurement of urban vitality and enriches its connotations. [ABSTRACT FROM AUTHOR]

Based on the engineering background of shield construction of a subway section in Chongqing, which needs to pass through a park and there is a lake inside this park, this paper adopts theoretical analysis methods and numerical simulation calculation methods to explore the distribution law of the seepage field and the characteristics of water pressure in lining segments during shield tunneling. The results show that, during the whole excavation of a double-track tunnel with EPB shield, the maximum vertical effective stress is about 4.24 MPa, which is located at the arch foot of the tunnel. The maximum effective stress in the horizontal direction is about 3.61 MPa, which is located on both side walls of the tunnel in the horizontal direction; after the left and right tunnels are excavated in sequence, a "double precipitation funnel-shaped" pore pressure distribution is formed around the tunnel; during the construction of the shield tunnel, the vertical displacement and horizontal displacement of the surrounding rock show an increasing trend and gradually tend to be stable values of 24.09 mm and 25.28 mm; the segment vault has settlement, the maximum settlement is 21.8 mm, the arch bottom has uplift, and the maximum uplift is 24.4 mm. The maximum horizontal displacement of the segment appears on both sides of the arch waist, and the maximum horizontal displacement decreases with the increase of excavation steps; the positive bending moment of the lining segment is mainly distributed on both sides of the arch crown, and the negative bending moment is mainly distributed on both sides of the arch bottom. The axial force of the lining segment is compressive stress, and the maximum axial force is mainly distributed on both sides of the arch waist. The maximum normal shear stress occurs on both sides of the segment arch bottom. The study conclusions provide theoretical foundation and a new guidance for long-term safety evaluation of underwater tunnel structures. [ABSTRACT FROM AUTHOR]

In the context of urbanization, frequent flood event have become the most common natural disasters, posing a significant challenge to human society. Considering the effects of urbanization on flood risk is critical for flood risk reduction and reasonable land planning strategies at the city scale. This study proposes an integrated approach based on remote sensing data using CA, Markov, and simplified hydrodynamic (FloodMap) models to accurately and effectively assess flood risk under urbanization. Taking Chongqing City as a case study, this paper analyzes the temporal and spatial variations in land use/land cover (LULC) in 2010, 2015, and 2018 and predicts the LULC for 2030, based on historic trends. Flood risk is assessed by combining the hazard, exposure, and modified vulnerability. The results suggest that the area of built-up land will increase significantly from 19.56% in 2018 to 25.21% in 2030. From 2010 to 2030, the area of medium and high inundation depths will increase by 10 and 16 times, respectively. Flood damage varies remarkably according to the LULC and return period. The expected annual damage (EAD) has been estimated to increase from USD 68 million in 2010 to USD 200 million in 2030. Flood risk is proportional to population and is significantly inversely proportional to socioeconomic level. The approach used here can provide a comprehensive understanding of flood risk and is significant for land-use policymaking and the management of flood control facilities. [ABSTRACT FROM AUTHOR]

Background: Rapid prediction with near infrared (NIR) spectroscopy on quality traits is pretty popular recently, for the convenience and simple operation. But to make good use of this technology, precise and suitable calibration equations are very important to get dependable result. In this study, we mostly refer to the building of the equation and how the pretreatment effect them. Methods: In this paper, near infrared (NIR) spectroscopy was used to simultaneously predict the quality traits of soybean, including oil content, protein content, oleic acid content, linoleic acid content, stearic acid content. Near infrared spectral data of a total of 112 samples is collected from given materials in Chongqing. Samples were scanned from 1000 nm to 2500 nm using a monochromator instrument (SuperNIR-2700). Calibration equations were developed from NIR data using partial least squares (PLS) regression with internal cross validation. In addition, in this study, we also cover the affection of different pre-treatments to the different calibration equations predicting different quality traits. And measure the effect with three indicators including R, SECV and RPD. Result: Eventually we find the most suitable combination of pre-treatments for each calibration equation predicting a certain trait soybean. The present study would lay the foundations of rapid detection of quality traits in soybean. [ABSTRACT FROM AUTHOR]

In the midsummer of 2022, a rare regional high-temperature event occurred in the Yangtze River Basin. Chongqing, as the center of this event, also experienced its strongest high temperature since 1961. In this paper, the characteristics of this event in Chongqing are reviewed in detail and compared with those of 2006. We have confirmed the following conclusions with detailed data: (1) In the midsummer of 2022, the number of days that the daily maximum temperature is exceeding 35 ℃ in Chongqing was the most since 1961, with the number of days that the daily maximum temperature above 40 ℃ increasing significantly compared with 2006. (2) The impact range of this event in Chongqing was quite extensive, especially the range with the daily maximum temperature exceeding 40 ℃ was the widest since 1961. (3) The high-temperature event was more extreme in 2022 than that in 2006. The maximum of daily maximum temperature was 45 ℃, and this is the first time that China has recorded a high temperature of 45 ℃ outside Turpan. There were 5 stations with daily maximum temperature exceeding 44 ℃, accounting for 1/3 of the number of stations with such temperature (15 stations) in China. (4) In the midsummer of 2022, Chongqing was dominated by the compound high-temperature day. Compared with 2006, the daytime high-temperature day decreased significantly, while the compound one increased obviously. [ABSTRACT FROM AUTHOR]

The operation status of the underground public space pedestrian system is of varying quality, but decision-makers and operators have no way of knowing its current operation status and how to retrofit it. In this paper, the social network model is adopted to compare and analyze the characteristic parameters of urban underground public space networks and users' pedestrian routes in 13 cases in the main urban area of Chongqing to judge the suitability of the two networks. The results show a mismatch between the existing urban underground public spaces and users' walking paths, with most users choosing to move within a fixed range and preferring to stop at nodes with larger areas, while there is an obvious waste of resources in the rest of the nodes. The overall connectivity and aggregation are generally low although the number of nodes in transit between the two networks matches. In addition, with different types of space compared, the cross-block urban underground public space network is more suitable for users' pedestrian routes, followed by the square and street types, and the compound type is ranked last. [ABSTRACT FROM AUTHOR]

Dedicated bus lane (DBL) is one of the effective measures to improve transit system efficiency and further promote transit priority. Then, the performance assessment of DBLs turns out to be an essential task for better reflecting the interests of all stakeholders. To this end, this paper presents a data-driven and multidimensional framework to objectively and accurately assess the detailed performance of DBLs from the perspective of passengers, government, and operators, respectively, in which multiple data sources (i.e., IC card and GPS data) and corresponding mining technologies are adopted to establish a series of criteria, enabling a before-and-after comparison for DBL opening. The proposed model has been applied to evaluate the efficiency of the DBL system in the city of Chongqing, China. The results reveal the benefits of opening DBLs, especially for government interests, in which DBLs use less public resources to expand more public welfare. But its role in strengthening transit system competitiveness is diminished, because the opening of DBLs did not significantly increase speed and volume. [ABSTRACT FROM AUTHOR]

BACKGROUND: The Ling sound test cannot provide the test of Chinese tone for preschool children with hearing aid and cochlear implants. OBJECTIVE: The paper tries to design a new tone test method composed of the Ling sound test and four Chinese tones to evaluate the hearing level of Chinese hearing-impaired children. METHODS: The tone identification rates of 20 cochlear implant children were statistically analyzed to verify the validity of the Ling sound test in the Chinese tone version. In addition, this paper analyzed the pronunciation characteristics of the Ling sound test in the Chongqing-accented Mandarin version of 20 subjects. RESULTS: The identification rate of Ling six sounds was more than 97.0%, the identification rate of tone was more than 81.0%, and the identification rate of vowels was 83.1%, which was higher than that of consonants 79.0%. The Ling sound test n the Chongqing-accented Mandarin version has a narrower frequency range. CONCLUSION: The results verify the effectiveness and feasibility of the Ling sound test in the Chinese tone version in the assessment of frequency range and tone identification for cochlear implant users. [ABSTRACT FROM AUTHOR]

Tobacco farmers often adopt additional multiple agricultural technologies (AMATs) in addition to implementing the standardized technical system in China. Based on the cross-sectional micro data of 346 households of Chongqing, China, this paper assesses the determinants and impacts of the adoption of AMATs on income by using a multinomial endogenous treatment effects model to correct for selection bias and endogeneity caused by observed and unobserved heterogeneity. The results show that (1) the adoption of combinations of AMATs is determined by the household head's education level, experience in tobacco growing, the shortest distance to nearby town, the amount of technical training, the ratio of land available for mechanical cultivation to tobacco land, the distance to extension station, and the ratio of leased land. (2) The adoption of combinations of AMATs has heterogeneous effects on farmers' income through yield and quality improvement. (3) The comprehensive combination of AMATs is not necessarily the best option for farmers. Due to the interaction between technologies such as complementary, substitute or supplementary effects, the moderate implementation of fertilizers and soil improvement is the most effective combination. The results of this research provide a scientific basis for improving the adoption efficiency of AMATs in China. [ABSTRACT FROM AUTHOR]

In recent years, the tourism industry has developed rapidly. However, traditional tourism information has the disadvantages of slow response speed and limited information content, which cannot reflect the evolution trend of spatial and temporal patterns of tourism information in time. Here, based on the Baidu Index, we construct an evaluation framework to analyse the spatial and temporal flow of tourism information in the Chengdu–Chongqing urban cluster from 2011 to 2021. Then, we analyse the urban links between different network levels from the evolution pattern. Finally, we use the geodetector model to analyse its driving mechanism. The results show that Chengdu and Chongqing are the most active cities in the study area in terms of tourism information. The unbalanced development of tourism information between Chengdu and Chongqing and other cities in the region gradually deepens during the period 2011–2019 (polarization effect), but the unbalanced development moderates after 2019. On the other hand, cities in the middle of the Chengdu–Chongqing cluster always have weak agglomeration effects of tourism information. Cities with high tourism information outflow rates in the Chengdu–Chongqing city cluster are mainly concentrated around Chengdu. The average outflow rate of Deyang is the highest, at 27.8%. Cities with low tourist information outflow rates are primarily located in the west, central and south. Ya'an is the city with the lowest outflow rate, with an average of −62.2%. Specifically, Chengdu is the dominant and most radiantly influential city. The tourism information of the Chengdu–Chongqing urban cluster shows a radial network with Chengdu and Chongqing as the core. The driving force analysis shows that the push factor of tourist source, such as the number of people buying pension insurance, is the core driving mechanism, while the pull factor of destination, such as the park green area, and resistance factors such as psychological distance, are in the secondary position. In general, this paper uses Internet tourism data to expand the traditional tourism information research of the Chengdu–Chongqing urban cluster, which can better respond to the changes and needs of the tourism market and provide reference for the spatial optimization of tourism destinations. [ABSTRACT FROM AUTHOR]

The planning process in urban rail transportation can be split into several stages, including line planning, timetabling, rolling stock scheduling and so on. The outcome of a stage provides inputs or constraints to the subsequent ones. However, while the output can be good or optimal at each stage, it rarely considers the global quality for the overall planning process. Furthermore, problems tackled at planning phase often use a more aggregate representation of reality, to achieve a more general overview. An integrated approach, while more complex to solve, may mitigate the gap between solution of different stages and a validation of a plan would still be required before its implementation in practice. In this paper, we focus on integrated optimization of train timetabling and rolling stock circulation for urban rail transit line with time-based origin-destination-dependent passenger travel demand and heterogeneous rolling stocks. The aim is to generate a comfortable timetable for passengers and an efficient timetable for operators. The objective is to minimize the total waiting time for passengers and the costs for operators, while constraints regarding train movements, passenger boarding and alighting, available rolling stocks and their capacity are considered. A mixed integer linear programming model is formulated and solved by an iterative programming approach. Computational experiments are performed on the Chongqing Rail Transit Line 2 to verify the efficiency and effectiveness of the proposed model and solving method. With respect to CPLEX, results show the proposed iterative programming approach has advantages both on computation time and solution quality. [ABSTRACT FROM AUTHOR]

In the new era, the Chinese government has implemented a strategic arrangement of high-quality development and a dual circulation development pattern, which injects new content and driving force into China's new urbanization. To reveal these changes, this paper constructs a quadrilateral diamond structure model of urbanization development dynamics of four-dimensional force + institutional force + innovation force, based on the comprehensive connotation of urbanization. Then the standard variance method and global principal component regression model are applied to empirically analyze the urbanization level and its development dynamics for Chongqing, a typical representative city of strategic importance in China, from 2000 to 2018. The results show that the following. (1) The urbanization level and all subsystems in Chongqing have shown a significant growth trend, of which the population and social subsystems have been maintaining relatively high growth rates, mapping the urbanization from a traditional efficiency-first economic growth model to a comprehensive benefit maximization model, focusing on people's livelihood and sustainable development. (2) The urbanization of Chongqing in the new era is an endogenous growth-oriented model driven by administrative, market, intrinsic, exterior, innovational, and institutional forces. This reflects the diversified and contemporary characteristics of the driving forces of urbanization in the new era, as well as the rationality and superiority of the institutional arrangement of the Chinese government. (3) The quadrilateral diamond structure model, which is based on the endogenous growth of the two forces of institutions and scientific and technological innovation, reveals the regional attributes and contemporary characteristics of the driving forces of urbanization in the new era. It can illustrate the Chinese experience for world urbanization research, and provides basic material for the world to understand and explore the characteristics and patterns of China's urbanization development. [ABSTRACT FROM AUTHOR]

Accurate monitoring of crop spatial distribution in topographically complex areas is of great significance for guiding agricultural management production and reasonable allocation of resources. However, scattered crop distribution and high spatial heterogeneity pose challenges for precise classification. The objective of this study was to explore a method for simultaneous precise identification of multiple crops with multi-temporal high-resolution satellite data under complex terrain conditions, thus further providing a theoretical and practical basis for crop identification in Chongqing city area and the complex low hills area in southwest China. The western Chongqing was selected as the study area. First, a multi-scale segmentation algorithm was adopted to construct homogeneous units from fields of the same feature type. This approach helped to achieve high accuracy classification by avoiding overly fragmented classification results based on pixel classification. Secondly, the multi-temporal Sentinel-2/MSI remote sensing images were used to explore the weathering patterns and characteristic parameters during the fertility period of major food crops. The spectral indices, such as NDVI, RVI and NDWI, were constructed to compare the differences in remote sensing spectral information of different crop types at various fertility periods based on ground sample points. Such information was then combined with the topographic features to determine the optimal combination for crop identification. Finally, an object-oriented decision tree logical classification rule set was established to extract major grain crop growing areas. The results showed that, (1) the multi-scale segmentation method was an effective approach that can make crop identification on a field basis. In addition, the vegetation edge segmentation was optimal at a segmentation scale of 30 and a compactness and shape factor of 0.5. (2) The target feature discrimination threshold was established by combining the spectral feature indices of NDWI in April, RVI in June, NDVI in August and NDVI in August with the topographic features such as altitude and slope. The overall accuracy of the classification reached 90.8%, being 85.7%, 83.3% and 80.7%, for paddy rice, maize, and sweet potato, respectively. This paper showed that the crop planting area identification method based on multiple spectral indices combined with topographic features can achieve high recognition accuracy and has practical significance. [ABSTRACT FROM AUTHOR]

In the era of the digitaleconomic, computing power has become an important indicator to measure the degree of national economic development. With analyzing the two national strategies of "Channel Computing Resources from the East to the West" progect and "Construction of Chengdu-Chongqing Economic Circle", and based on the construction of Chengdu-Chongqing Hub Node, the reasons that why Chengdu-Chongqing hub node has been laid out as one of the eastern hub nodes were analyzed. It due to four aspects, namely, strategic location advantage of computing, data integration system guarantee, computing infrastructure compaction, and maturity of computing application scenarios. Further, the operations in the advanced data center of Western (Chongqing) Science City demonstrate that the nationalcomputing hub built in Chengdu-Chongqing economic circle boosts the project that channels computing resources from the east to the west. Then the paper discussed the coordinated development between Tianfu data center cluster and Chongqing data center cluster, as well as the coordinated development between national computing hub built in Chengdu-Chongqing economic circle and national computing hub built in Guizhou province. It suggested that Tianfu data center cluster and Chongqing data center cluster should build coordination mechanisms from six aspects, including the network, data, computing power, industry, algorithm and energy. The neighboring national computing hubs can implement coordination based on the allocation of computing power business, the cross-domain circulation of data elements, and new business formats for digital cooperation. [ABSTRACT FROM AUTHOR]

China's Hot Summer and Cold Winter zone, with a 550 million population, accounts for 45% of China's building energy consumption; as such, building retrofits could offer substantial energy savings. This paper presents results from a dynamic thermal modeling study of a typical urban multistory residential building under three types of air conditioning (A/C) operating schedules. Seven energy-saving retrofit measures (external wall insulation, roof insulation, double-glazing, air infiltration control, window shading, communal staircase design, and energy-efficient A/C) were evaluated, and the retrofit strategy with the highest annual energy savings and lowest thermal discomfort was identified. This retrofit strategy was subsequently evaluated for other flats (apartments) with different orientations and positions in the typical building. The annual space-conditioning energy could be reduced by 59%–68%, depending on the flat location, orientation and A/C operating schedule. The findings were then scaled up to estimate the potential energy savings in the city of Chongqing. More than 320 multistory residential buildings were represented by 12 archetypes. Space-conditioning energy consumption was reduced by up to 58% (18.8 TWh). This work provides evidence of the potential energy savings of city-scale retrofit that could aid China in reducing building energy consumption and achieving net-zero carbon emissions by 2050. It was possible to explore a wide range of refurbishment options for China's highly energy-consuming Hot Summer and Cold Winter zone with hot, humid summers and mild, chilly winters using dynamic thermal models. The simulation models developed in this paper revealed that double-glazing with air infiltration control is the most effective retrofit measure for middle-floor flats, but for top-floor flats, roof insulation is the most effective; south-facing flats consume more high energy consumption than north-facing flats. Furthermore, high-rise buildings consume less energy than low-rise buildings per square meter, and one-bedroom flats consume more energy than three-bedroom flats per square meter. This study also demonstrated the procedure to develop thermal comfort evaluation methods, A/C operating schedules, and construction parameters from literature in this climate zone when there were no standards or databases available. Findings offer a tangible, clear retrofit strategy that considers different A/C operating schedules, flat locations, and building archetypes. It can assist decision-making by practitioners and homeowners aiming to upgrade the building stock of this climate zone which covers 3.4 billion m2 with a 550 million population to reduce energy consumption and improve occupant comfort. [ABSTRACT FROM AUTHOR]

Since 2000, the real estate industry has experienced rapid development, and at the same time, it has driven the rapid growth of housing prices, and the trend of housing prices has attracted attention. This paper integrates genetic algorithm and particle swarm algorithm to optimize BP neural network, and establishes a housing price prediction model based on mixed genetic particle swarm BP neural network. The average data of housing prices in Chongqing, China from 2000 to 2020 and several main factors affecting the trend of housing prices were selected as experimental data. Through the training and simulation prediction based on the mixed particle swarm BP neural network, the error between the predicted value and the actual value was within 0.5%, the validity and accuracy of the model are proved. At the same time, this paper predicts the average price of residential commercial housing in Chongqing in 2021, which provides a reference for the government's macro-control and sellers to carry out residential commercial housing. [ABSTRACT FROM AUTHOR]

Globally, co-production serves as a crucial approach to promote sustainable neighborhood rehabilitation. However, in China, where the governance system is characterized by strong state discourse power and a lack of public participation tradition, neighborhood rehabilitation encounters significant challenges, leading to project postponements or even failures due to unsuccessful co-production activities. To reveal the hidden problems, this paper aims to gain an in-depth understanding of the stakeholders' co-production roles and their participation structure in the co-produced sustainable neighborhood rehabilitation process from multiple dimensions. Using the case in Chongqing, the data was collected through questionnaire surveys and in-depth interviews. Social network analysis was utilized as the research method, and one-mode and two-mode networks were established to depict six relationship types with using diverse network indicators. This study revealed the high complexity of stakeholder structure, the awkward role of grass-rooted government, the dilemma of public voices and perceptions, uneven involvement in the co-production process, and the dynamic path of co-production formation. Drawing upon co-production theory, this paper elucidates the intricate mechanism of co-produced neighborhood rehabilitation in China. It offers valuable implications for policymakers and urban planners for project promotion, and contributes empirical insights to research in similar governance systems across the global context. • Stakeholder structure in co-produced sustainable neighborhood rehabilitation is highly complex. • Grass-roots government sectors have low discourse power in practice. • Resident-initiated organizations may not always accurately represent the views and interests of in-situ residents. • Uneven involvement of stakeholders can result in a downplayed co-design process and a weak role for investors. • Six network types are interconnected and interdepend. [ABSTRACT FROM AUTHOR]

• Substantial surveys identify that bus queuing, merging, and repeated opening doors can significantly affect bus dwell time. • A Markov chain is designed to characterize the effect of vehicles in adjacent lane and passengers on bus merging. • A comprehensive model is proposed to estimate bus dwell time and bus queuing time. • The actual performance of the comprehensive model is validated in real cases in three cities. • The probability of bus overtaking is highly correlated with bus service time and average stop service time. The precise estimation of bus dwell time (BDT) is immensely important as it directly impacts the reliability of bus schedules and the accuracy of arrival time predictions. Various factors—such as the behavior of buses merging into the main traffic flow, uneven distribution of passengers on board, and frequent bus queues—jointly lead to a high variability of the BDT. To achieve an accurate estimation of BDT across various stop types, a comprehensive BDT model is developed in this paper. First, based on berth occupancy, probabilistic models are constructed for different bus arrival scenarios, which are then used to study corresponding bus queuing times. Second, the Bureau of Public Roads function is employed to characterize the obstruction effect occupants on the bus impose on boarding passengers. Combined with this function, a bus service time model is proposed considering the bus opening doors more than once and in-vehicle crowding. Third, the bus merging process is discretized to cope with the volatility of the time interval required for a bus to leave the bus bay. A Markov chain model is designed to calculate the time buses have to wait before merging. Case studies conducted in Qingdao, Chongqing and Beijing, China, demonstrate the effectiveness of the comprehensive model both during off-peak and peak periods. Furthermore, this paper incorporates overtaking rules into the comprehensive model to examine the influence of bus overtaking willingness and various overtaking policies on bus queuing times. Through numerical analysis, the key link is between willingness to overtake, service time and the likelihood of bus overtaking is disclosed. [ABSTRACT FROM AUTHOR]

Using the CRITIC method, comprehensive index evaluation method, VAR model, coupling coordination model and other methods, this paper evaluates the comprehensive development of the population economy and eco-geological environment composite system in the twin-city economic circle of Chengdu–Chongqing region from 2000 to 2020, verifies the dynamic coupling relationship between subsystems and measures the coupling coordination degree of complex system. Meanwhile, the differences in the development process of each subsystem are discussed and the spatial–temporal evolution characteristics and laws of coupling coordination of the composite system during the research period are analyzed. The results reveal the following: (1) There is a long-term coordinated relationship between population, economy and eco-geological environment in Chengdu–Chongqing region, which have the conditions for emergence and generation. (2) The subsystems of population, economy and eco-geological environment in Chengdu–Chongqing region show an overall upward trend, among which the Sichuan part obviously outperforms the Chongqing part. Besides, the growth rate of the economy subsystem is significantly higher than that of the population, eco-geological environment subsystem. (3) The coupling coordinated development of the composite system has shown a benign upward development trend, gradually changing from "composite spiral structure" to "two cores outstanding, peripheral collapse, the west superior to the east", while the main coordination state has developed from "Basic synergy—Economic lag" in 2000 to "Basic synergy—Population lag" in 2022. In addition, Cheng-De-Mian and Yuzhong districts with the better level of economic development have shown "Advanced synergy—Ecological lag". [ABSTRACT FROM AUTHOR]

Accurate and reliable prediction of PM2.5 concentrations is the basis for appropriate warning measures, and a single prediction model is often ineffective. In this paper, we propose a novel decomposition-and-ensemble model to predict the concentration of PM2.5. The model utilizes Ensemble Empirical Mode Decomposition (EEMD) to decompose PM2.5 series, Support Vector Regression (SVR) to predict each Intrinsic Mode Function (IMF), and a hybrid algorithm based on Differential Evolution (DE) and Grey Wolf Optimizer (GWO) to optimize SVR parameters. The proposed prediction model EEMD-SVR-DEGWO is employed to forecast the concentration of PM2.5 in Guangzhou, Wuhan, and Chongqing of China. Compared with six prediction models, the proposed EEMD-SVR-DEGWO is a reliable predictor and has achieved competitive results. [ABSTRACT FROM AUTHOR]

The study takes 10 urban agglomerations in China as the research object, focusing on the Chengdu-Chongqing urban agglomeration, and applies Data Envelopment Analysis (DEA) to measure and compare their scientific input and output efficiency of universities. First, this paper analyzes the input and output of scientific research in universities in major provinces in China in detail. Second, according to the construction principles of the indicator system, using qualitative interview to construct evaluation indicators of university research efficiency. Third, using DEA method, first analyze the input and output profile of some urban agglomeration universities such as Chengdu-Chongqing economic circle, measure and compare their research input and output efficiency, then compare and analyze the research efficiency of research-type sample universities within Chengdu-Chongqing economic circle, and conduct a projection study of non-DEA effective sample universities. The main conclusions are as follows: first, the average efficiency of scientific research in universities in Chengdu-Chongqing and other urban agglomerations in 2020 has slightly increased compared with that in 2016, but the gap between urban agglomerations is prominent, and the innovation level of scientific research in higher education institutions in urban agglomerations needs to be improved. Second, there is a mismatch between the themes of research, funding and human resources in research-oriented universities in the Chengdu-Chongqing economic circle. Third, there is considerable room for improvement in research efficiency, and the influence of scale on overall efficiency is weak. We found that excessive investment in scientific research in universities is the main reason for the non-effect. [ABSTRACT FROM AUTHOR]

The appropriate sizes of scale-breeding industries are causing increasing attention in that rational scale-breeding industries may both meet the meat demand of the market and avoid serious environmental problems. In this paper, the appropriate scales of breeding-type family farms were studied from the perspective of quantifying resource losses. The mathematical models about quantifying resource losses were built, and then the evaluation index system of resource losses was established. More than one hundred family farms in Sichuan province and Chongqing city of China located in the subtropics were selected as research cases and were classified as small-, medium- and large-scale family farms, whose unit resource losses and resource loss rates were both evaluated by the index system. Results show that the unit resource losses and the resource loss rate of medium-scale family farms are the lowest among these three kinds of family farms. Therefore, medium-scale farms are moderate, and then are recommended for scale-breeding industries. Implications: Appropriate sizes are essential for the green development of scale-breeding industries. The external environment factors and internal resource effect should be considered. The unit resource losses and the resource loss rate of medium-scale family farms are the lowest among these three kinds of family farms. Therefore, medium-scale farms are optimistic, and then are recommended for scale-breeding industries. For medium-scale family farms, the scale of 800–999 pigs is optimistic. Furthermore, it is very necessary to adopt green cycle. [ABSTRACT FROM AUTHOR]

In order to meet customers’ individual needs for delivery methods and specific time in urban distribution, this paper introduced the concept of customer preference to describe the delivery needs of home delivery and self-pickup services, and established vehicles path optimization model with different delivery options with the optimization goal of minimizing the total ope-rating cost. Considering the complexity of the model, it introduced a variety of operators, and designed an adaptive large neighborhood search algorithm and improved to solve the problem. Finally, combined with a case analysis of a distribution case in Nan’an district of Chongqing city, the validity of the model and algorithm is verified. [ABSTRACT FROM AUTHOR]

The Local Climate Zone (LCZ) classification scheme is a vital method of building a category dataset for high-resolution urban land. For the development of urban meteorology, air pollution and related disciplines, the high-resolution classification data of urban buildings are very important. This study aims to create LCZ datasets with detailed architectural characteristics for major cities and urban agglomerations in China, and obtain more accurate results. We constructed 120 m resolution land use datasets for 63 cities (mainly provincial capitals, municipalities directly under the Central Government, important prefecture-level cities and special administrative regions) and 4 urban agglomerations in China based on the local climate zone (LCZ) classification scheme using the World Urban Database and Access Portal Tools method (WUDAPT). Nearly 100,000 samples were used, of which 76,000 training samples were used to provide spectral signatures and 23,000 validation samples were used to ensure accuracy assessments. Compared with similar studies, the LCZ datasets in this paper were generally of good quality, with an overall accuracy of 71–93% (mean 82%), an accuracy for built classifications of 57–83% (mean 72%), and an accuracy for natural classifications of 70–99% (mean 90%). In addition, 35% of 63 Chinese cities have construction areas of more than 5%, and the plateaus northwest of Chengdu and Chongqing are covered with snow all year round. Therefore, based on the original LCZ classification system, the construction area (LZC H) and the snow cover (LCZ I) were newly added as the basic classifications of urban LCZ classification in China. Detailed architectural features of cities and urban agglomerations in China are provided by the LCZ datasets in this study. It can be applied to fine numerical models of the meteorological and atmospheric environment and improve the prediction accuracy. [ABSTRACT FROM AUTHOR]

【Objective】This paper explored the temporal and spatial expansion characteristics and industrial operation mode of farmers’ cooperatives in different topographical areas of Chongqing, mastered the development law of farmers’ cooperatives in Chongqing and analyzed the differences in the selection of different industrial modes, in order to provide data support for promoting the classified cultivation of cooperatives and the formulation of differentiated support policies.【Method】This paper used 2528 farmers’ cooperatives in Chongqing as a sample, comprehensively used terrain distribution index, standard deviation ellipse and other methods to analyze the temporal and spatial patterns and expansion characteristics of cooperatives of different industrial types in four types of terrain. And combined with the questionnaire survey, combed and refined the cooperative operation mode. 【Result】（i） The development of farmers’ cooperatives in Chongqing showed four growth stages in general, with slow growth from 2002 to 2006, rapid growth from 2007 to 2010, the growth rate slowed down from 2011 to 2014, and the growth rate from 2015 to 2018 has dropped significantly. From the perspective of topographical area, the growth rate of Area Ⅳ is the fastest, followed by Area Ⅱ and Area Ⅰ, and Area Ⅲ had the slowest growth rate.（ii） The growth advantages of cooperatives in different industries vary significantly. The growth advantage zone of livestock and poultry industry was Area Ⅳ. The growth advantage zone of the fruit and vegetable, grain and oil, and comprehensive industries were Area Ⅰ and Area Ⅱ. The growth advantage zone of the flower, tree, tea, and peppercorn industries are Area Ⅱ, the tobacco and Chinese medicinal materials industries are Area Ⅲ and Area Ⅳ.（iii） Except for the grain and oil industry cooperatives in the southeast-northwest direction from 2002 to 2006, the rest of the industrial cooperatives had a southwest-northeast distribution at various stages.（iv） There were six main modes of cooperative industrial operation, the livestock, poultry, fruit and vegetable, flower and tree and grain and oil industries use the ‘company + farmers’ cooperative + base + farmer’ model. The ‘company + farmers’ cooperative + farmer’ model was used by fruits and vegetables, flower and tree, grain and oil industries. The industries that use the ‘farmers’ cooperative + base + farmer’ model include fruit and vegetable, flower and tree industries, and the industries that use the ‘Internet+ farmers’ cooperative + farmer’model include livestock, poultry and other industries. The industries of the ‘farmers’ cooperative + farmer household’ model include fruit and vegetable, grain and oil industries, and livestock industry using the model of ‘company + farmers’ cooperative + base + family farm’. 【Conclusion】The number of farmers’ cooperatives in Chongqing is growing, and the advantageous area of different industries has a difference, and it has evolved in the northeast direction, and the operation mode of each industry is diverse. According to the spatio-temporal expansion characteristics of the cooperative and the local conditions, we should accurately find the mode of industrial operation and promote the steady development of cooperatives. [ABSTRACT FROM AUTHOR]

This paper summarizes the latest progress of variable viscosity slick water technology in China, analyzes the application of variable viscosity slick water in unconventional gas reservoirs in Sichuan and Chongqing, and puts forward the development direction of variable viscosity slick water. The variable viscosity slick water realizes the real-time switching of low, medium and high viscosity liquids by adjusting the concentration of drag reducer and / or introducing cross-linking agent. The research of drag reducer focuses on the synthesis and performance evaluation of polyacrylamide containing AMPS or SSS salt-tolerant groups and hydrophobic associating polymer, to meet the needs of preparing fracturing flow-back fluid mixing and change viscosity. The research on the performance of variable viscosity slick water mainly focuses on the influence law of viscosity on sand carrying performance, fracture morphology and drag reduction performance, but it is not yet determined what viscosity is suitable for what reservoir. The application of variable viscosity slick water in unconventional gas reservoirs in Sichuan and Chongqing was successful. The overall viscosity in tight gas is higher than that in shale gas, and the sand carrying capacity in deep shale gas needs to be further enhanced. Hydrophobically associating polymer drag reducer and solid drag reducer are the development direction of variable viscosity slick water. It is expected to solve the problems of high frictional resistance of high viscosity liquid and potential environmental risks of emulsion drag reducer. This paper has certain guiding significance for the research and application of variable viscosity slick water. [ABSTRACT FROM AUTHOR]

The paper studies the Chongqing hotpot(重庆火锅) and two general types of lead-in phrases(过门) of Chongqing Thumb Fight(划拳). This paper mainly discusses the birthplace and maker of Chongqing hotpot and the origin of the two primary lead-in phrases: Good Brothers(兄 弟好) and Disorderly Chopping Firewood(乱劈柴). The results of studying the Chongqing hotpot and two types of lead-in phrases were found as follows: 1. The Yangtze River is the birthplace of the Chongqing hotpot. 2. The trackers and porters working for the wharves along the Yangtze River create the original Chongqing hotpot. 3. Th encircling rivers cultivate the Good Brothers and the mountainous forests stimulate the Disorderly Chopping Firewood [ABSTRACT FROM AUTHOR]

With the development of 3D technology, based on the perspective of 3D video, this paper analyzes the principle of 3D video, establishes the perspective model of 3D video, and discusses the modeling process in detail. Then, from the perspective of 3D video, this paper studies the three-dimensional intervention model of public art in Beijing, Shanghai, Chongqing, and Tianjin. Through the combination of public art and rural culture, the countryside can obtain vitality through art and popularize and promote rural culture and image. In general, this paper provides some ideas and experience for the research of public art in rural culture from the perspective of 3D video. [ABSTRACT FROM AUTHOR]

Knowledge sharing among teachers is one of the important ways to improve their teaching and research ability. From the perspectives of teachers' knowledge sharing willingness, knowledge sharing ability, knowledge sharing environment, knowledge sharing technology support, knowledge sharing effect, and so forth, this paper constructs a teacher knowledge sharing behavior evaluation model, develops a knowledge sharing behavior evaluation index system, and proposes a comprehensive teacher's knowledge sharing behavior evaluation method based on the improved entropy-TOPSIS method. This is a comprehensive evaluation method combining subjective and objective weights, which avoids the subjectivity of traditional expert evaluation methods and other multilevel and multi-index weight determination methods and makes the evaluation results more objective, accurate, and more realistic. Finally, by taking the example of evaluating knowledge sharing behavior of teachers in a university of Chongqing, China, this paper verifies the feasibility and practicability of the proposed comprehensive teachers' knowledge sharing behavior evaluation system and method. [ABSTRACT FROM AUTHOR]

CO2 is the main greenhouse gas. Urban spatial development, land use, and so on may be affected by CO2 and climate change. The main questions studied in this paper are as follows: What are the drivers of CO2 emissions of expanding megacities? How can they be analyzed from different perspectives? Do the results differ for megacities at different stages of development? Based on the XGBoost model, this paper explored the complex factors affecting CO2 emissions by using data of four Chinese megacities, Beijing, Tianjin, Shanghai, and Chongqing, from 2003 to 2017. The main findings are as follows: The XGBoost model has better applicability and accuracy in predicting carbon emissions of expanding megacities, with root mean square error (RMSE) as low as 0.036. Under the synergistic effect of multiple factors, population, land size, and gross domestic product are still the primary driving forces of CO2 emissions. Population density and population become more important in the single-factor analysis. The key drivers of CO2 emissions in megacities at respective developmental stages are different. This paper provides methods and tools for accurately predicting CO2 emissions and measuring the critical drivers. Furthermore, it could provide decision support for megacities to make targeted carbon-emission-reduction strategies based on their own developmental stages. [ABSTRACT FROM AUTHOR]

Shared parking, as an important means of revitalizing static traffic facilities, has received widespread attention from all walks of life. At the microlevel, this paper analyzes a total of more than one million parking data points (including the license plate information of each vehicle, the time of entering and leaving the parking lot, the parking time and the parking fee, and so on) in Chongqing, studies the change cycle and change characteristics of the data, and draws the conclusion that the traffic volumes of office buildings and shopping malls are significantly different on weekdays and weekends. Based on the performed analysis, this paper establishes a supply-and-demand-based appreciation model to project the impact of the implementation of shared parking on real estate value appreciation. The calculation results show that the implementation of shared parking can increase the value of the parking lot studied in the example by 17% of its original value. Although the model established in this article is aimed at the sharing of parking spaces between an office building in the city's central business district and the surrounding shopping mall, it can also be extended and applied to the evaluation of parking space sharing between general buildings. Overall, this paper provides effective methods into revitalizing parking space resources to ease urban traffic congestion. [ABSTRACT FROM AUTHOR]