City Size Research Articles

Does land market matter for urban energy efficiency? Empirical evidence from cities in China

Improving urban energy efficiency on the basis of cost-effectiveness is an important topic of universal concern across the world. The input cost has great influence on energy efficiency. Thus, as one of the important factors in the production progress, land price may exert an energy effect via affecting the urban industries. With a focus on land price levels and the variability, our study investigates the impact of land market on urban energy efficiency, based on the panel data of China's prefecture-level cities. Further, by exploring effects of the segment land markets, our study reveals the exact price features in land market that have driven the changes in energy efficiency of cities. The main results are: (a) Either of the price level and the price variability in urban land market has a positive net effect on energy efficiency. When price level and variability increase by 1%, urban energy efficiency respectively increases by 0.06% and 0.04%, and the effects vary with city's population size and geographic location; (b) An increase of land price level improves energy efficiency by optimizing industrial structure and reduces energy efficiency by weakening industrial production efficiency, while an increase in land price variability exerts a positive impact on energy efficiency by adjusting industrial structure; (c) The price level factor affecting urban energy efficiency is mainly the commercial-residential land prices, while the difference between commercial-residential and industrial land prices is the variability factor that affects energy efficiency.

The mechanism for selecting low carbon urban experimentation cases in the literature and its impact on carbon emission performance

Recently, low carbon urban experimentations have received increasing attention in dealing with climate change. As low carbon urban experimentations are the pilots to test low carbon practices, it is necessary to examine the factors influencing the case-selection mechanism in the low carbon urban experimentation literature and its impact on cases’ carbon emission performance. We developed hypotheses about the case-selection mechanism using economic, urban and other factors. We observed that the scholar proximity and population size of cities are positively related to their frequency to be selected as cases. The case frequency of low carbon urban experimentations in the literature is positively associated with their carbon emission performance. Thus, policymakers should pay attention to the lessons from frequently selected cases in the low carbon urban experimentation literature. As scholar promixty is positively associated with case selection in low carbon urban experimentation literature. Practitioners can promote the development of low carbon research institutions and scholars, which can help cities gain more low carbon development knowledge and increase their carbon emission efficiency in the end.

The Impact of Urban Sprawl on Carbon Emissions from the Perspective of Nighttime Light Remote Sensing: A Case Study in Eastern China

This paper collects the nighttime light data and six control variables of 77 cities in the eastern China region from 2000 to 2020 and analyzes the spatio-temporal changes of urban sprawl and carbon emissions in the eastern China region. Using the baseline regression model, the correlation and influencing factors between urban sprawl and carbon emissions are explored. The results show that although the impact of urban sprawl on carbon emissions in the eastern China region is positive, it is the result of a trade-off of various factors. Different factors have different impacts on carbon emissions, and urban expansion of different city sizes also has different impacts on carbon emissions in the eastern China region. This paper uses nighttime light data to measure the urban sprawl index more finely, directly explores its impact on carbon emissions from the perspective of urban sprawl and conducts an in-depth analysis of multiple external factors and different city types, providing references for decision-makers to construct sustainable low-carbon city development models and low-carbon city planning systems from different dimensions.

The role of digital governance on carbon emission performance: evidence from the cities in yangtze river delta, China

Rapid industrialization and ambitious socio-economic targets have presented significant challenges to China’s carbon neutrality process. However, digital transformation offers new opportunities for sustainable development. This research examines the influence of digital governance (Digov) on carbon emission performance (Cep) and explores its underlying mechanisms. The study utilizes data from cities in China’s Yangtze River Delta from 2011 to 2019. The results show that digital governance has significantly improved carbon emission performance, a conclusion that remains robust even after conducting a series of rigorous tests and addressing endogeneity concerns. The main impact mechanisms of digital governance on carbon emission performance include energy intensity reduction, energy consumption scale reduction, industrial structure adjustment, and energy consumption structure optimization.Furthermore, the results indicate that the variation in carbon emission reduction due to digital governance can be attributed to differences in city administrative level, city size, and government capacity. In particular, digital governance plays a pivotal role in facilitating the sustainable transformation of resource-based cities.From the perspective of digital governance, this study provides effective recommendations and valuable insights for achieving low-carbon targets and promoting sustainable development of cities.

청소년기 비만에 영향을 미치는 요인 분석

Objectives Obesity is the second most important problem after smoking in many countries around the world, causing various and serious problems. The purpose of this study was to analyze the factors that affect obesity as the obesity rate of Korean adolescents increases every year, and to seek action plans to prevent obesity. Methods For this purpose, the data on adolescent health behaviors surveyed from 2018 to 2021 were used and analyzed. Of the 234,694 adolescents from the first grade of middle school to the third grade of high school who participated in the survey, 221,036 were analyzed, excluding those with missing values in major independent variables such as body mass index, eating habits, and physical activity. (Rao-Scott X2test) was conducted and multi-factor logistic regression analysis was performed to analyze the influencing factors. Results As a result of the study, gender, grade level, economic status, city size, academic level, soda intake, missing breakfast and fast food intake, and exercise for more than 60 minutes were associated with obesity. Conclusions As a way to prevent obesity, it is necessary to improve eating habits and promote physical activity, which should be considered not only in individuals and families, but also in schools. It will be necessary to prepare an environment for promoting physical activity in school and to have a balanced diet and management for a healthy diet. This suggests the need for policies to prevent obesity, such as educational programs.

A survey to investigate transport conditions in depopulating cities in Illinois

Despite the global population increase, many cities in the world are depopulating. While the literature focuses heavily on the challenges brought by an increasing population, depopulating cities face many challenges as well. In particular, the management and maintenance of infrastructure often becomes challenging in depopulating areas. To identify the challenges related to transport, this study conducts a survey on depopulating cities in Illinois. Asking questions about the availability of travel modes, the challenges faced by users of each mode, commonly/possible implemented solutions to facilitate mobility, and investment and funding in transport, this study provides an analysis of transport conditions in depopulating cities from an administrative standpoint. A descriptive analysis of the survey responses is presented to provide aggregated results and to exhibit how responses vary with city size and location. This study also highlights the importance of evaluating existing conditions to implement tailored solutions to local contexts instead of applying blanket solutions that often fail to benefit the residents.

Effects of digital economy and city size on green total factor productivity

Utilizing the digital economy’s contribution to green total factor productivity is a key strategy for accelerating China’s green growth, although more research is still needed to understand the mechanism of this influence. This study uses panel data from 282 Chinese prefecture-level cities from 2011 to 2019 to empirically assess the impact of the digital economy and city size on GTFP. First, GTFP overall exhibits an upward trend with excellent spatial correlation and minimal regional variation. Second, the findings demonstrate that, while surrounding locations’ GTFP is not affected by the digital economy, local productivity can be improved. Third, the heterogeneity study demonstrates that the digital economy contributes more to local GTFP in the eastern region compared to the central and western regions, with the central region making the largest contribution to GTFP in the surrounding regions; the first, second, and third tier cities have more contributions from the digital economy to local and neighboring GTFP than the fourth and fifth tier cities. Fourth, city size positively modifies the relationship between the green total factor productivity and the digital economy. The western region is where the positive moderating effect of city size expansion is greatest. Moreover, compared to first-, second-, and third-tier cities, the fourth- and fifth-tier cities have a stronger beneficial moderating effect of city size increase. In light of this, we should focus on the growth of the digital economy, optimize city scale, and fully exploit the scale effect produced by the concentration of the digital industries and the spillover effect produced by the spread of the digital technology.

Impacts of UHI on Heating and Cooling Loads in Residential Buildings in Cities of Different Sizes in Beijing–Tianjin–Hebei Region in China

The heating and cooling energy consumption levels of urban buildings account for a large and rapidly growing proportion of the total end-use energy consumption of society. The urban heat island (UHI) effect is an important factor influencing the spatiotemporal variations in the heating and cooling energy consumption levels of buildings. However, there is a lack of research on the impact of the UHI on the heating and cooling energy consumption of buildings in cities of different sizes in the Beijing–Tianjin–Hebei urban agglomeration, which is the most urbanized region in northern China. We selected rural reference stations using the remote sensing method, and applied an hourly data set from automatic weather stations, to examine the impact of the UHI on the typical residential building heating and cooling loads in three cities of varied sizes in the Beijing–Tianjin–Hebei urban agglomeration through building energy simulation. The main conclusions were as follows. As the UHI intensity (UHII) increased, the heating load difference between urban and rural areas decreased, while the cooling load difference between urban and rural areas increased in the cities. The average daily heating loads in the urban areas of Beijing, Tianjin, and Shijiazhuang were 8.14, 10.71, and 2.79% lower than those in their rural areas, respectively, while the average daily cooling loads in the urban areas were 6.88, 6.70, and 0.27% higher than those in their rural areas, respectively. Moreover, the absolute hourly load differences between urban and rural areas were significantly larger during the heating periods than during the cooling periods, with the former characterized by being strong at night and weak during the day. During the peak energy load period, the contribution of the UHI to the peak load of residential buildings varied between the cities. During the stable high-load period, from 18:00 to 07:00 the next day in the heating periods (from 18:00 to 05:00 the next day in the cooling periods), the hourly loads in the urban areas of Beijing, Tianjin, and Shijiazhuang were 3.15 (2.48), 3.88 (1.51), and 1.07% (1.09%) lower (higher) than those in their rural areas, respectively. Our analysis highlights the necessity to differentiate the energy supplies for the heating and cooling of urban buildings in different sized cities in the region.

Assessment of Dynamic Object Information Utilization Service in a Control Center for Each Urban Scale via Fuzzy AHP

Recently, the demand for citizen-sensible service solutions such as traffic, crime prevention, and disasters in smart cities is increasing. In order to provide technology-based smart city services, local government control centers could be utilized. Accordingly, this paper presented a method for selecting a control center-based dynamic object information utilization service model through in-depth interviews with 26 related local government control center operation personnel. A comparative analysis according to the size of the local government to which the evaluator belongs was also performed. As a methodology, Fuzzy AHP was used, which can support rational decision-making by mathematically expressing ambiguous phenomena such as subjective and uncertain judgments. The summary of the research results is as follows. Services related to recent incidents in South Korea (e.g., school zone traffic accidents and lowland inundation) were identified as very important. These social issues are significant factors in policy decisions. In comparing the results for each urban scale, the importance of pedestrian safety services on backside roads and main road traffic services was found to be important in the metropolitan area and regional, medium, and small cities, respectively. This was attributed to metropolitan cities with high population density, and medium and small cities experiencing alienated traffic information. In metropolitan areas, new services are highly important owing to the demand for a more scientific control service and future mobility based on a sound control infrastructure. In medium and small cities, facility management services were assessed relatively highly owing to the poor conditions of regional cities with a lack of supervising personnel in the field and a lack of surveillance system infrastructure. This paper was able to confirm the difference in service preference by city size, and it is necessary to select the optimal service model considering these results.

Does City Size Affect COVID-19 Spread and Policy Measures?

Does City Size Affect COVID-19 Spread and Policy Measures?

The Sixty-Year Trajectory of Homicide Clearance Rates: Toward a Better Understanding of the Great Decline

In 1962, the FBI reported a national homicide clearance rate of 93%. That rate dropped 29 points by 1994. This Great Decline has been studied and accepted as a real phenomenon but remains mysterious, as does the period of relative stability that followed. The decline was shared across regions and all city sizes but differed greatly among categories defined by victim race and weapon type. Gun homicides with Black victims accounted for most of the decline. We review the evidence on several possible explanations for the national decline, including those pertaining to case mix, investigation resources, and citizen cooperation. Our preferred explanation includes an upward trend in the standard for arrest, with strong evidence that although clearance-by-arrest rates declined, the likelihood of conviction and prison sentence actually increased. That result has obvious implications for the history of policing practice and for the validity of the usual clearance rate as a police performance measure.

Long dawn before take-off: Spatio-temporal patterns and mechanisms of China's urban growth, 1900–1978

Urbanization is an important part of the modernization of traditional societies, and the growth of major cities is a prominent manifestation of urbanization. This paper uses historical maps and demographic data to measure the urban population and construction land growth of 47 major cities in China during 1900–1978, and examines the influence factors with different politic backgrounds. (1) China's cities were generally experiencing rapid growth. The growth rate of urban land was higher and more stable than urban population. (2) The growth rate of city size was negatively correlated with initial sizes, deviating Gibrat's law; the population's rank-size structure converged the Zipf's model during 1910–1949, but deviated during 1949–1978. The spatial pattern of urban system gradually shifted from regionalized core-periphery to a nationally-integrated, regional-egalitarian structures. (3) The patterns and mechanisms of urban population growth and land growth are not identical, reflected in the change of the distribution of urban construction land per capita. Urban land growth is more correlated with capital investment. (4) China was in a typical preconditions for take-off phase before 1949, but did not fit into the take-off phase as Rostow argues in 1949–1978. This period is crucial in comprehending China's rapid take-off after 1978, as it established the industrial foundation at the expense of urbanization. The previous process has left indelible traces and highlights the problem of the abnormal growth of urban land in recent years, thereby prompting a reflection on the role of land finance in China.

MIGRATION HINTERLANDS OF CITIES IN THE ALTAI KRAI

The study of intraregional migration in Russia is complicated by short time series and a limited set of published data, particularly at the municipal level. The publicly available data allow only general evaluation of migration parameters, e. g. the migration turnover, the net migration features, etc. More complete data, for example, on movements between municipalities, could be obtained from the regional statistical offices on special requests. Based on such data on intraregional migration in the Altai Krai in 2014-2018, the hinterlands of the urban okrugs were identified, and some characteristics of those hinterlands were revealed.The migration turnover with ten urban okrugs of the region was calculated for urban and rural settlements of the Altai Krai. A settlement was attributed to the hinterland of a particular urban okrug basing on the maxi-mum migration turnover with it. The hinterlands were delimited in two ways, i.e. with and without considering the capital city of Barnaul. By this we evaluated how the exclusion of migration to/from the regional capital, which dominates the system of intraregional migration links, affects the migration preferences of settlement residents.The results of the study showed that the Barnaul hinterland includes more than half of the Krai’s territory with approximately 60% of the region’s population. The hinterlands of other cities are proportional to the population of their centers and are also influenced by their location in relation to the regional capital. Without considering Barnaul, several cities, such as Rubtsovsk and Slavgorod considerably expand their influence, while the hinterland of Biysk, the second-largest city in the region, changed only slightly. Despite the importance of the size of cities, the mutual disposition of subcenters and their location in relation to the regional center play a critical role in the intraregional migration. The study gives an idea of principal directions of inter-settlement migration in the Altai Krai.

The Impacts of Tourism Development on Urban–Rural Integration: An Empirical Study Undertaken in the Yangtze River Delta Region

A viable pathway towards achieving shared prosperity is made possible by the growth of tourism, which encourages the movement of urban and rural elements. This harmonious alignment of tourism development and urban–rural integration also helps to narrow the gap between urban and rural areas. This study uses a set of panel regression models to investigate whether tourism growth promotes urban–rural integration within 41 cities in the Yangtze River Delta Region of China from 2010 to 2020. The findings show that the effect of tourism development on urban–rural integration is significantly positive, displaying significant heterogeneity across various times and city sizes. Furthermore, tourism development exhibits a threshold effect and city-type heterogeneity concerning urban–rural integration. The effect demonstrates significant continuous growth along with the expansion of economic growth. However, the impact of tourism development on urban–rural integration demonstrates a distinct promotional threshold effect, and its positive effect appears to be weakened.

Exploring the effect of city size on carbon emissions: Evidence from 259 prefecture-level cities in China.

As a gathering place for human production activities, cities are the main places where energy consumption and carbon dioxide emissions occur. How to accurately measure city size and test the impact mechanism of city size on carbon emissions of different city levels is still controversial. This study uses the global nighttime light data to identify urban bright areas and built-up areas, and accordingly constructs the city size index of 259 prefecture level cities in China from 2003 to 2019. It avoids the problem of only considering the single index of population size or space size, and makes the measurement of city size more reasonable. We use a dynamic panel model to study the impact of city size on urban carbon emissions per capita, and discuss the heterogeneity of various cities under different population levels and economic development levels. The empirical results indicate that in the scale of cities in China showed a fluctuating growth trend in recent years. The city size index of most cities is clustered at medium and high values. The city size index of cities with different economic development levels and different population-scale levels shows obvious gradient differences but maintains an upward trend. The expansion of supercities (with a population of more than 5 million) introduces a drastic increase in carbon emissions. The carbon emissions growth caused by the expansion of cities that are classified as third tier and below is the smallest, while that caused by the expansion of cities that are classified as first-tier is the largest. The findings suggest differentiated emissions reduction suggestions for cities with different sizes.

Operating cost of public services and city size

Many studies have shown that some factors related to city population such as the economies or diseconomies of scale, the variations in the urban pattern linked to the city size, the special conditions of the urban environment in large cities or the changes in the level of service directly impact on the unit operating cost of urban public services. However, research has not been able to isolate their real influence, or even in what direction they work. As a result, the relationship between the city population and the unit operating cost of their public services remains unclear: some authors state that the unit operating cost of public services decreases when the population increases; others that it increases or that it follows a U-shaped function with an optimal city size. For a sample of 4875 Spanish municipalities, the combined analysis of per-capita and per-unit of infrastructure expenditure ratios has allowed us to delve into the central role of two of the aforementioned factors: the level of service and the urban pattern. Thus, for the services of public lighting, water supply, sewage and sanitation, waste collection and disposal, parks and pavement maintenance and street cleaning, higher levels of per-capita spending have been found both in municipalities with under 1000 and above 50 000 residents. However, in the smallest municipalities, the higher level of spending per resident is boosted by a less-compact urban pattern, while in the largest cities, the reason would be a better level of service.

Urbanisation and Geographical Signatures in Observed Air Temperature Station Trends Over the Mediterranean and the Middle East–North Africa

We update observed temperature trends in the Mediterranean and the Middle East–North Africa (MENA) region, assess their temporal and spatial features and investigate possible influences from urbanisation. Monthly mean temperature time-series of 370 stations are acquired from the CRUTEM4.6 and GSOD datasets and converted into suitable format for statistical analysis. The calculated annual and seasonal temperature linear trends for 1981–2020 indicate a strong warming with a MENA station average annual trend equal to 0.36 ^circ {hbox {C}}/decade and a faster warming rate for spring (0.43 ^circ {hbox {C}}/decade) and summer (0.45 ^circ {hbox {C}}/decade). These trends are correlated with longitude, revealing faster warming rates over the eastern Mediterranean and Middle East. The stations are characterised as rural or urban centre with the use of the Global Human Settlement Model (GHS-SMOD) spatial grid that accounts for population, city size and shape for the year 2000. The trend derived for the urban centre stations is an annually averaged 0.1 ^circ {hbox {C}}/decade greater than for the rural or all stations, and more prominent during summer and autumn. Hence a discernible, but small, urbanisation signature is revealed.

The dynamic resilience of urban labour networks.

Both cities and markets are well understood as complex systems which are amenable to analysis using physically inspired methods. Cities have shown fascinating universality with size, while labour markets modelled as networks have considerable explanatory power. Labour markets are a particularly attractive domain of study in this context due to societal importance, the influx of high-resolution data as well as exogenous influence of automation. While much previous work has studied the economic characteristics of cities as a function of size and examined the exposure of urban economies to automation, this has often been from a static perspective. In this work, we examine the diffusive properties of labour markets and examine their variance across cities. More specifically, we identify the occupations which are most important in promoting the diffusion of beneficial or deleterious properties. To this end, we propose a new measure of node centrality empSI. We find that these properties of influence vary considerably with city size.

On the scaling patterns of infectious disease incidence in cities

Urban areas with larger and more connected populations offer an auspicious environment for contagion processes such as the spread of pathogens. Empirical evidence has revealed a systematic increase in the rates of certain sexually transmitted diseases (STDs) in urban areas with larger population sizes. With rampant urbanization worldwide, it is increasingly important to improve our understanding of the key drivers of these systemic infection patterns. Using confirmed-case data for three STDs in U.S. metropolitan areas, we investigate the scaling patterns of the incidence of these infectious diseases in urban areas. The most salient features of these patterns are that, on average, the incidence of infectious diseases that transmit with less ease i) scale more steeply with population size, ii) are more variable across cities of similar size, and iii) are less predictable across time. These features are explained using a simple mathematical model of contagion and also through the lens of a new theory of urban scaling. These theoretical frameworks help us reveal the links between the factors that determine the transmissibility of infectious diseases and the properties of their scaling patterns across cities.

Demography of Censorship: Examining Correlations Between Community Demographics and Materials Challenges in Canadian Libraries

This study examines materials challenges in Canadian libraries, compiled by the Canadian Federation of Library Associations (CFLA), with the intention of identifying demographic trends in patron challenge behaviour. By cross-referencing the CFLA data with five demographic fields from the 2016 Canadian census of population (median age, city size, educational attainment level, median income, and political representation), the study aims to determine whether challenges of a certain nature are more likely to occur in communities with certain demographic profiles. The study identifies twenty-two challenge categories derived from user complaints and three ideological alignments of challenges based on the political ideology standards set by moral foundations theory. Though the available sample is too small to draw any definitive conclusions, some strong trends were apparent. Findings show that the most common challenge types, challenges to racist content and sexual content, are fairly consistent throughout demographic groupings, but notable correlations were found between demographic profiles and materials concerning LGBTQIA+ issues. Progressive-leaning communities were far more likely to challenge homophobic/transphobic materials while conservative-leaning communities challenged more LGBTQIA+-positive works. From an ideological standpoint, young communities tend to be the most progressive in their challenge behaviour, while communities with a low level of educational attainment tend to be the most conservative in their challenge behaviour.