Big Cities In China Research Articles

An Emergency Decision-Making Method for Urban Rainstorm Water-Logging: A China Study

With the rapid development of the urbanization process, rainstorm water-logging events occur more frequently in big cities in China, which causes great impact on urban traffic safety and brings about severe economic losses. Water-logging has become a hot issue of widespread concern in China. As one kind of natural disasters and emergencies, rainstorm water-logging has the uncertainties of occurrence, development, and evolution. Thus, the emergency decision-making in rainstorm water-logging should be carried out in stages according to its development trend, which is very complicated. In this paper, an emergency decision-making method was proposed for urban water-logging with a hybrid use of dynamic network game technology, Bayesian analysis, and multi-attribute utility theory. The dynamic game process between “rainstorm water-logging” and “decision-making group” was established and the dynamic generation of emergency schemes was analyzed based on Bayesian analysis in various stages of water-logging. In terms of decision-making attributes, this paper mainly considered two goals, i.e., ensuring smooth traffic and controlling emergency cost. The multi-attribute utility theory was used to select the final scheme. An example analysis in Guangzhou of China showed that the method is more targeted and can achieve emergency management objectives more effectively when compared with traditional methods. Therefore, it can provide reference for the scientific decision-making of emergency management in urban rainstorm water-logging.

Uncovering energy saving and carbon reduction potential from recycling wastes: A case of Shanghai in China

With fast development and urbanization, Chinese cities are facing several challenges including issues of environmental pollution, climate change, resource depletion and landfills shortage. Waste recycling is one effective way to respond these challenges. Under such a situation, this paper aims to evaluate energy saving and carbon reduction potential of recycling wastes by taking Shanghai, the biggest city in China, as a case study. Results show that 8.7 Mt standard coal (tce) and 16.81 Mt CO2 could be reduced under current recycling system in Shanghai. And recycling of waste steel and nonferrous metals were the two dominant contributors, accounting for about 44% and 42% of energy saving, and 60% and 33% of CO2 reduction, respectively. If the recycling rates of main recyclable wastes were improved to 100%, additional 6.44 Mt energy and 10.02 Mt CO2 could be further saved, mainly from recycling waste glass, waste plastic and waste metals. Adoption of RPF (Refuse Plastic & paper Fuel) could further contribute to 1.24 Mt energy saving and 2.67 Mt CO2 reduction. Finally, policy implications on establishing a mature recycling system and promoting RPF technologies are discussed, in which the potential on reducing total energy consumption and CO2 emission of Shanghai can reach 6.6% and 4.9%, respectively.

Unveiling cabdrivers’ dining behavior patterns for site selection of ‘taxi canteen’ using taxi trajectory data

ABSTRACTIn recent years, some big cities in China have established a number of ‘taxi canteens,’ which are special cafeterias intended only for cabdrivers to dine and rest. To dine and rest at the appropriate time is one of the most concerned problems for cabdrivers, since long dining delay may affect their health and driving safety, and arbitrary parking for dining will be fined and may even cause dangerous traffic accidents. The establishment of ‘taxi canteens’ is expected to mitigate these problems. But little has been done to examine and optimize the site selection of taxi canteens. This paper presents a data-driven approach to allocate ‘taxi canteens’ throughout a city with the main objective of minimizing the total distance between all dining demand locations identified from taxi GPS trajectories and the corresponding closest ‘taxi canteen’ locations. We propose a dining event detection method that considers four features using support vector machine and further identifies the spatiotemporal patterns of cabdrivers’ dining. A constrained optimization model is proposed to select locations for ‘taxi canteens.’ A case study is conducted in Wuhan, China, to evaluate how the identification of cabdrivers’ dining behavior patterns can support the site selection of ‘taxi canteens.’ The results indicate that the proposed method has superior performance.

General analysis of factors influencing cataract surgery practice in Shanghai residents

BackgroundIt was reported that lack of knowledge, less confidence of medical services, commute difficulties, and poor economic conditions would be the main barriers for cataract surgery practice. The influencing factors could have changed in cities with high developing speed. Shanghai is one of the biggest cities in China and the world. The purpose of the study was to explore the factors influencing cataract surgery practice in Shanghai.MethodsThis was a population-based, cross-sectional study. A total of 2342 cataract patients older than 50 years old with cataract-induced visual impairment or who had undergone cataract surgery were recruited from rural and urban areas of Shanghai. Participants accepted a face-to-face structured questionnaire. Data were collected on patient demographics, education, work, income, health insurance, awareness about cataracts disease, treatment and related medical resources and deration policy, transportation and degree of satisfaction with hospitals.ResultsThere were 417 patients who had received cataract surgery, 404 of them supplied complete information in the questionnaire. More female subjects (64.6%) than male subjects (35.4%) accepted cataract surgery among the 404 patients. Of the patients with cataract history, 36.4% of surgery patients were equal or older than 80. More people with urban medical insurance received surgery (p = 0.036). Patients who received surgery were more satisfied with local medical service (p = 0.032). In urban area, Lower income and difficulties with commutes were related to a higher rate of surgery.ConclusionsCataract patients with the following features were more inclined to receive surgery: female, old age, better awareness. In urban areas low income and difficult commutes did not represent barriers for cataract surgery, probably because of appropriate cataract surgery promotion policies recent years in Shanghai. In rural areas, better healthcare reimbursement policies would likely lead to a higher uptake of cataract surgery. Further cohort studies with more controls could supply stronger evidence for our viewpoint.

Optimization of rainfall networks using information entropy and temporal variability analysis

Rainfall networks are the most direct sources of precipitation data and their optimization and evaluation are essential and important. Information entropy can not only represent the uncertainty of rainfall distribution but can also reflect the correlation and information transmission between rainfall stations. Using entropy this study performs optimization of rainfall networks that are of similar size located in two big cities in China, Shanghai (in Yangtze River basin) and Xi'an (in Yellow River basin), with respect to temporal variability analysis. Through an easy-to-implement greedy ranking algorithm based on the criterion called, Maximum Information Minimum Redundancy (MIMR), stations of the networks in the two areas (each area is further divided into two subareas) are ranked during sliding inter-annual series and under different meteorological conditions. It is found that observation series with different starting days affect the ranking, alluding to the temporal variability during network evaluation. We propose a dynamic network evaluation framework for considering temporal variability, which ranks stations under different starting days with a fixed time window (1-year, 2-year, and 5-year). Therefore, we can identify rainfall stations which are temporarily of importance or redundancy and provide some useful suggestions for decision makers. The proposed framework can serve as a supplement for the primary MIMR optimization approach. In addition, during different periods (wet season or dry season) the optimal network from MIMR exhibits differences in entropy values and the optimal network from wet season tended to produce higher entropy values. Differences in spatial distribution of the optimal networks suggest that optimizing the rainfall network for changing meteorological conditions may be more recommended.

How website quality affects online impulse buying

PurposeThe purpose of this paper is to investigate the impact of website quality on online impulse buying behavior (OIBB) in China, and assess the moderating roles of sales promotion and credit card use.Design/methodology/approachAn online and personal survey from 1,161 online shoppers belonging to three big cities of China – Beijing, Shanghai, and Nanjing – was conducted. A random sampling technique was utilized for data collection. Data were analyzed using validity and reliability tests, confirmatory factor analysis, and structural equation modeling.FindingsThree major findings discovered are: first, the website quality positively affects the OIBB; second, the sales promotion significantly influences OIBB and acts as a strong moderator on the relationship between website quality and online impulse buying; and third, the online impulse purchases are positively influenced by use of credit card, and the use of credit card enhances the relationship between website quality and online impulse buying.Research limitations/implicationsFirst, the website quality positively affects the OIBB; second, the sales promotion significantly influences OIBB and acts as a strong moderator in the relationship between website quality and online impulse buying; and third, online impulse purchases are positively influenced by credit card use. Moreover, credit card use enhances the relationship between website quality and online impulse buying.Originality/valueThis research is the first to investigate the relationship between website quality and OIBB in China, with sales promotion and credit card use as moderators.

Spatial Characteristics and Migration Mechanism of Population Suburbanization in Chinese Big City

Urban spatial expansion and population suburbanization are very common after urban growth to a certain stage, and also an important research topic of human geographer. Chinese cities have experienced unprecedented growth since the lunch of reforms in the late 1990s. Studies have found that the leading cities in China such as Beijing and Shanghai are undergoing the process of suburbanization, while the country as a whole is still at the stage of urbanization. However, it is difficult to judge whether suburbanization has happened by the traditional method. In this paper, the graphic analysis method is introduced to analyze the spatial distribution of population in big cities, and the migration analysis method is introduced to analyze the source of new population. The results show that: with the rapid urbanization and population growth, the urban population distribution area in Chinese big cities is expanding very much; Inner suburbs are the fastest population growth areas, expanding continuously as circles, and the newly increased people mainly are migrants from the central city and intraprovincial urban people; Outer suburbs reflect unbalanced population growth as a leap-frogging, with faster rates at locations of county/district governments and prioritized development districts, and the newly increased people mainly are interprovincial rural people. It is the general spatial model of population growth in the suburbs of big cities in China, which is obviously different from those in western countries.

Self-Organized Bike Redistribution in Urban City

Bicycle is an affordable and environmental friendly alternative to private cars and public transportation. Recently, some big cities in China established the bike-sharing system (BSS) through which people can rent bikes offered by government or commercial companies. However, due to limited parking space, it is often difficult for bikers to park their bicycles in bike stations. This paper envisions approaching this problem by using a self-organized bike redistribution strategy: as time passes by, bike society will form an equilibrium state of bike redistribution.

The EV Charging Piles Planning Based on the MOTLBO Algorithm

Recently, the electric vehicles (EV) are promoting rapidly in many big cities of China, but the charging problem has become a big obstacle for the development of EV. In this article, the demand of EV is determined on the basis of EV proportion and divided into 2 portions: (1) Centralized demand (2) Decentralized demand. The charging total mileage is determined based on the state of charge (SOC) and the orderly-free charging strategy is presented considering the demand of the users. Moreover, a new multi-objective teaching–learning based optimization (MOTLBO) algorithm is put forward to plan the quantity and location of the concentrated charging pile in the region considering the situation of the new city. Results showed that the performance of MOTLBO was promising and benefits can be achieved easily. As Compared to other methods, the method used in this article picks out the hierarchical planning idea firstly and addicts the man–machine interaction into the free-orderly charging strategy.

A dietary and nutritional status survey among young children in five big cities of China.

To investigate the dietary patterns and nutritional status of young children living in urban environments in China. A cross-sectional study was conducted of 750 children aged 6 - 35 months living in 5 large cities in China. The survey methodology included a physical exami-nation, blood hemoglobin measurements and a 24 hour dietary recall questionnaire Results: The educational lev-el of participant mothers was high (79% had attended college or university or higher), which may not be fully representative across all areas of urban China. Overall anthropometric nutritional status indicators were within acceptable ranges based on national recommendations, and there was no evidence of severe micronutrient defi-ciencies. However, we identified three significant nutritional issues that warrant attention: 1.) Later than optimal introduction and low-intake of animal-based iron-containing foods into the diet, and a need for greater inclusion of vitamin B-1 rich foods among 12-35 month old children. 2.) Presence of significant rates of anemia in 6-11 and 12-23 month old children. 3.) An increased risk of overweight/obesity. Since food availability and affordability are no longer major issues in the well developed parts of urban China, achieving further im-provements in the diet and nutrition of young children in these environments is likely require more specific edu-cation to parents and other significant carers such as grandparents. The relatively high educational level and so-cio-economic status of the population group is likely to facilitate the uptake of such measures in this population group.

Spatial accessibility of country parks in Shanghai, China

To deal with the challenges of nature conservation and public recreation in a rapidly urbanization, many big cities in China have launched country parks programs. However, seldom literature focus on the accessibilities of country parks as public infrastructure. By calculating the spatial accessibility indexes based on the Two-Step Floating Catchment Area (2SFCA) method, this paper evaluates the spatial accessibility of 14 country parks to 240 streets/towns in Shanghai. Our analysis indicates that the spatial differences of the accessibility of streets/towns are significant; the accessibility in Shanghai’s central city and the Chongming Islands are lower than those of other urban areas. Based off our results, the spatial accessibility of streets/towns is far from ideal, with 85% of streets/towns having an index value less than 0.0025. Most of Shanghai’s residents in streets/towns require a travel time of more than 60min. The authors suggest that country parks cannot be replaced by urban parks in Shanghai because of their unique functionality and attraction to residents. To improve the spatial accessibility of country parks, the authors advocate for the improvement of population distribution in Shanghai and the integration of road networks and public transportation sites to country parks. Our results for Shanghai are applicable to other big cities that experienced similar rapid urbanization in China, East Asia, and Southeast Asia.

Assessment of transport emissions impact and the associated social cost for Chengdu, China

ABSTRACTChengdu, the capital city of Sichuan province, is the fourth biggest city in China with over 15 million residents and 3.4 million vehicles. In Chengdu, transport and other mobile sources accounted for over 27% of the city's PM2.5 emissions (CDEPB, 2016), posing negative impacts on public health, local environment, and the climate. This study estimated impacts from transport-related emissions (CO2, CH4, N2O, PM10, PM2.5, NOX, SOX, CO, and HC) and evaluated the associated social cost for Chengdu from 2005 to 2013. The study also assessed the city's transport performance in terms of its eco-efficiency with the socioeconomic and environmental concerns. The activity-based methodology was adopted to produce the emission inventories, while utilizing meta-analysis and localizing the emission social cost factors based on Chengdu's economic and demographic reality to support social cost assessment. The study marks the first attempt in literature to evaluate Chengdu's transport emission social cost. The following were observed in the study: (i) in 2013, the social cost of all transport emissions in Chengdu was around US$3 billion, with the lowest estimate of US$449 million and the highest estimate of US$4.7 billion; (ii) trucks, private cars, and motorcycles were the major contributors, while NOX, PM2.5, and CO were the key pollutants to public health; (iii) if GHGs (CO2, CH4, and N2O) were excluded, the upper range of social cost of transport air pollutants would be from US$2.4 billion to US$4.1 billion, or 1.6%–2.8% of the Chengdu's GDP.

3-year risk prediction of Coronary Heart Disease in hypertension patients: A preliminary study.

Hypertension is associated with increased morbidity and mortality in Coronary Heart Disease (CHD). However, the risk factors that cause hypertension patients develop into CHD remain unclear. This paper aims to study traditional and nontraditional risk factors of CHD in hypertension population. Data were extracted from the regional medical big data system of Shenzhen, a big city of China. In this study, we included 3395 hypertension patients aged from 30 to 79 years old. Among them, 1153 CHD events occurred within 3 years after they were first followed-up. A logistic regression model was used to evaluate the risk factors quantitatively and predict 3-year risk of CHD events. The results showed that traditional general-population-based CHD risk factors such as age, body mass index, diabetes, hyperlipemia, and chronic kidney disease still remained predictive in hypertension patients. In addition, the odds ratio (95% confidence interval) of CHD was 1.54 (1.19 to 2.01) for emotional or mental disorders, and 1.69 (1.21 to 2.34) for sleep disorders. And the model showed a good discriminative performance with an AUC of 0.839. It offered a new insight for hypertension patients that keeping psychological health and maintaining a good sleep quality could be helpful in preventing CHD. Given the high risk for CHD in patients with hypertension, control of these risk factors may have a substantial preventive effect on CHD.

Occurrence and risk assessment of trace metals and metalloids in sediments and benthic invertebrates from Dianshan Lake, China

The present study measured concentrations of Cr, Ni, Cu, Zn, As, Cd, Sb, and Pb in surface sediments and two benthic invertebrate species (Anodonta woodiana and Bellamya aeruginosa) collected from Dianshan Lake, located in the Yangtze River Delta. The Dianshan Lake acts as one of the most important drinking water sources to Shanghai, the biggest city in China. Concentrations of trace metals and metalloids ranged from 0.04 mg/kg for Cd to 288.0 mg/kg for Zn. Substantial bioaccumulation in invertebrates was observed for Zn and Cu based on the biota-sediment accumulation factor (BSAF) measurements. The results revealed that concentrations of metals and metalloids in sediments from Dianshan Lake were at the lower end of the range of levels found in other regions of China. The assessment of three significantly inter-related evaluation indices, including the geo-accumulation Index (Igeo), potential ecological risk factor (Eri), and mean probable effect concentration quotients (Qm-PEC), suggested that sediment-associated trace elements exhibited no considerable ecological risks in the studied watershed. However, the target hazard quotient and hazard index analysis suggested that selected elements (particularly As) accumulation in edible tissues of benthic invertebrates could pose potential health risks to local populations, especially fishermen. Given that wild aquatic organisms (e.g., fish and bivalves) constitute the diet of local populations as popular food/protein choices, further investigations are needed to better elucidate human health risks from metal and metalloid exposure via edible freshwater organisms.

Tuo Shan Yan Dam and City Ningbo: Exploring the Historical Logic of Urban Water Management through a Big City of China

Tuo Shan Yan Dam and City Ningbo: Exploring the Historical Logic of Urban Water Management through a Big City of China

Unequal Distribution of Overweight Adolescents in Immigrant-Rich Areas: Analysis of Disparities among Public and Private School Students in Shanghai, China.

Accelerated urbanization and rising immigration to the big cities in China has resulted in education policies that produce disparate treatment of immigrant and non-immigrant students. The two types of students frequently wind up in different types of junior high schools. However, there is little research on whether disparities exist between students in public and private schools with regard to overweight. This study aims to address this gap through a comparison of the overweight status of junior high school students in public and private schools in Shanghai and explore the possible reasons for the observed differences. Students from two public and two private junior high schools were measured. In order to determine what factors might shape overweight among adolescents. Logistic regression analysis was used to assess associations between overweight and personal characteristics, birth-related factors, levels of physical activity, diet, family socioeconomic status and school environment. Students in private schools proved more likely to be overweight (15.20%, p < 0.05) than public school students (10.18%). Similarly, gender, breastfeeding, parental care and number of classes excluding physical education per day were found to be significant factors. However, private school students were also influenced by gestational age (yes/no: OR = 4.50, p < 0.001), frequency of snacks (sometimes/often: OR = 0.53, p < 0.01) and family income (¥6001–12,000/below ¥6000: OR = 3.27, p < 0.05). Time for lunch was the sole risk factor for public school students in the study (p < 0.05). To reduce the unequal distribution of overweight students between the two types of schools, interventions that consider different multiple risk factors should be implemented.

大城市成年人的幸福感“出生顺序效应”

基于267位中国大城市成年居民的总体幸福感数据分析，结果发现：1) 不同出生顺序的女性的总体幸福感以及精力、心情忧郁或愉快、松弛或紧张因子分数存在显著差异；2) 不同出生顺序男性的总体幸福感分数不存在显著差异；3) 女性独生子女的幸福感低于长子和次子，末子幸福感略高于独生子女，低于长子和次子。总体幸福感的“出生顺序效应”或与家庭结构、家庭角色、家庭互动及父母教养方式的差异有关。 Based on a survey data collected from 267 adult residents in big cities of China, we found that birth order effect exists in female participants on general well-being score and on scores of energy level, cheerful-distracted level and relaxed tense level, while no birth order effect has been seen among male participants. Specifically, among female participants, only child participants’ general well-being is lower than first-born and middle-born participants, while last-born participants’ general well-being is a little bit higher than only child but lower than first-born and middle-born participants. The birth order effect on general well-being may be related to differences in family structure, the role different birth order children play in the family, family reaction mode and parenting.

Fostering a More ‘Cultured’ City through Inclusion: Metrics for Sense of Belonging for Migrants in Chinese Urban Areas

Over the past four decades, infrastructural and economic development in Chinese cities has outpaced its cultural development. As the proportion of people living in cities in China quintupled from 1950 to 2014, from 11% to 54% according to a 2009 report by McKinsey, while at the same time various challenges have paved the way to limit cultural prosperity and quality of life in cities. Cities currently face number of problems: Vehicle-oriented streets are not friendly to pedestrians; public spaces are designed without users in mind [1]; communities are isolated from one another [2]; and finally creative industries are lagging behind other industries according to a 2014 Forbes report.It seems that China's urban development states a condition of “survivability” rather than “livability”. What is understood from the notion of livability within a city today is to be able to sustain quality of life through holistic planning strategies rather than purely economic ones. Such cities create robust natural environments as well as built environments, social equity as well as social stability. And as a result both a more reliable creative prosperity and economic prosperity have been maintained.This paper will seek to establish a 3-pillar approach to social inclusion and will examine each of these through issues related with migrants in China facing today. It seems that there is a great potential in using mobile and web-based technologies to generate rapid and sustainable solutions for migrants. There is also an enormous potential to develop feedback mechanisms for these solutions that can become part of the ‘culture’ of living in big cities in China.

International Conference on Water Resource and Environment 2016 (WRE2016)

PrefaceThe 2016 International Conference on Water Resource and Environment (WRE 2016) was held from July 23rd to July 26th, 2016 in Shanghai, the biggest city in China and one of the largest urban areas in the world. The technical program comprised eleven international keynote speakers, four interesting oral presentation sessions and a stimulating poster session.The key focus of the conference was on the areas “Wastewater and Water Treatment”, “Soil, Water and Environment” and “Water Resource and Hydrology”. A double presentation session was necessary for the latter area.This volume is based on the proceedings of the WRE 2016 and contains 73 specially selected manuscripts submitted to the WRE 2016 conference. The electronic submission and handling of manuscripts via the conference website, including the selection of reviewers and evaluation of manuscripts, were comparable to the procedures usually applied to manuscripts submitted as regular contributions to high-ranking journals.The organization of this conference and the preparation of this volume would have been impossible without the tremendous efforts and dedication of many individuals as well as a large team of reviewers. We express our sincere thanks to all authors and presenters for their valuable contributions.The 2017 International Conference on Water Resources and Environment (WRE 2017) will be held in Qingdao, which is one of the most beautiful tourism cities in China. Everybody is welcome to submit high quality papers to WRE 2017!

Purchase Intention for Electric Vehicles in China From a Customer-value Perspective

Vehicle exhaust emissions are a major contributor to the creation of smog in big cities in China. Hence, the manufacture of electric vehicles (EVs) has become an emerging industry, and receives special attention from the Chinese government for its great advantages of lack of pollution and energy efficiency. However, Chinese people have been very reluctant to purchase EVs. In this study, I recruited a sample of 454 participants and explored which factors affect customers' purchase intention for EVs. Results revealed that customers pay more attention to the environmental value of EVs but have fears related to electricity leakage, explosions, or radiation exposure from batteries. These findings indicate that the Chinese government's support for EVs is still not sufficient, and that government promotion of a low-carbon lifestyle must be enhanced.