Hasil untuk "Urbanization. City and country"

Valerio Martinelli

Starting from the relationship between urban planning and mobility management, TeMA has gradually expanded the view of the covered topics, always remaining in the groove of rigorous scientific in-depth analysis. This section of the Journal, Review Notes, is the expression of continuously updating emerging topics concerning relationships between urban planning, mobility and environment, through a collection of short scientific papers written by young researchers. The Review Notes are made of four parts. Each section examines a specific aspect of the broader information storage within the main interests of TeMA Journal. This section, International Regulations and Legislation for the Energy Transition, explores the challenges and opportunities in the urban context to understand the evolving landscape of the global energy transition. The RED III Directive (2023/2413) introduces more ambitious targets for renewable energy than RED II and provides for Renewable Acceleration Areas (RAAs) to expedite plant authorizations. This gives a more prominent role to urban and regional planning, which must integrate energy, environmental, and infrastructure criteria into location decisions. The Italian case demonstrates how multilevel governance, along with operational tools such as strategic assessments and digital platforms, is crucial in defining RAAs. Cities thus assume a central role in decarbonization processes. This paper highlights opportunities and critical issues towards a faster, fairer, and more sustainable energy transition.

Rafael Prieto-Curiel

Cities are some of the most intricate and advanced creations of humanity. Most objects in cities are perfectly synchronised to coordinate activities such as jobs, education, transportation, entertainment, and waste management. Although each city has its own characteristics, some commonalities can be observed across most cities, such as issues related to noise, pollution, segregation, and others. Further, some of these issues might be accentuated in larger or smaller cities. For example, with more people, a city might experience more competition for space, so rents would be higher. The urban scaling theory provides a framework for analysing cities in terms of their size. New data for analysing urban scaling theory allow for an understanding of how urban metrics change with population size, whether they apply across most regions, or whether patterns correspond only to some countries or regions. Yet, reducing a city and all its complexity to a single indicator might simplify urban areas to the extent that their disparities and variations are overlooked. Often, the differences in living conditions across different parts of the same city are greater than the degree of variation observed between cities. For example, in terms of rent or crime, within-city variations might be more significant than between cities. Here, we review some urban scaling principles and explore ways to analyse variations within the same city.

Wisdom Richard Mgomezulu, Paul Thangata, Daniel Njiwa

The impact of trade liberalization on Malawi’s economy has been a hotly debated topic. To shed light on the subject, a study was conducted using the PEP-1–1 CGE model and the latest Malawi’s Social Accounting Matrix (SAM) from 2019. The results were eye-opening, revealing the potential effects of the African Continental Free Trade Area (AfCFTA) on various sectors of the economy. The removal of trade tariffs is predicted to have a significant impact on prices, with a decrease of 26.31% in the agricultural sector alone, services (−7.88%), public administration (−9.92%), and manufacturing and industry (−11.23%) imposing hopes of improving food affordability and food security. However, it is expected to have adverse impacts on wage rates in the agricultural sector (−18.78%), manufacturing and construction (−19.01%), services (−2.79%) and public administration (−15.81%). Additionally, while exports are expected to increase, the country’s balance of payments may suffer as imports are likely to outweigh foreign earnings. This could also lead to a decrease in government revenue from taxes. To mitigate these effects, the study suggests implementing export restructuring strategies, particularly in industries like manufacturing and construction, and promoting diversification of local production to boost competitiveness and improve wage rates. With these measures in place, the government will not only offset potential losses but also tap into new sources of taxable income.

Chenyi Cai, Biao Li, Qiyan Zhang et al.

Urban morphology, examining city spatial configurations, links urban design to sustainability. Morphology metrics play a fundamental role in performance-driven computational urban design (CUD) which integrates urban form generation, performance evaluation and optimization. However, a critical gap remains between performance evaluation and complex urban form generation, caused by the disconnection between morphology metrics and urban form, particularly in metric-to-form workflows. It prevents the application of optimized metrics to generate improved urban form with enhanced urban performance. Formulating morphology metrics that not only effectively characterize complex urban forms but also enable the reconstruction of diverse forms is of significant importance. This paper highlights the importance of establishing a bi-directional mapping between morphology metrics and complex urban form to enable the integration of urban form generation with performance evaluation. We present an approach that can 1) formulate morphology metrics to both characterize urban forms and in reverse, retrieve diverse similar 3D urban forms, and 2) evaluate the effectiveness of morphology metrics in representing 3D urban form characteristics of blocks by comparison. We demonstrate the methodology with 3D urban models of New York City, covering 14,248 blocks. We use neural networks and information retrieval for morphology metric encoding, urban form clustering and morphology metric evaluation. We identified an effective set of morphology metrics for characterizing block-scale urban forms through comparison. The proposed methodology tightly couples complex urban forms with morphology metrics, hence it can enable a seamless and bidirectional relationship between urban form generation and optimization in performance-driven urban design towards sustainable urban design and planning.

N. Garcia-Chan, L. J. Alvarez-Vazquez, A. Martinez et al.

In this paper we propose a novel traffic flow model based on understanding the city as a porous media, this is, streets and building-blocks characterizing the urban landscape are seen now as the fluid-phase and the solid-phase of a porous media, respectively. Moreover, based in the interchange of mass in the porous media models, we can model the interchange of cars between streets and off-street parking-spaces. Therefore, our model is not a standard conservation law, being formulated as the coupling of a non-stationary convection-diffusion-reaction PDE with a Darcy-Brinkman-Forchheimer PDE system. To solve this model, the classical Galerkin P1 finite element method combined with an explicit time marching scheme of strong stability-preserving type was enough to stabilize our numerical solutions. Numerical experiences on an urban-porous domain inspired by the city of Guadalajara (Mexico) allow us to simulate the influence of the porosity terms on the traffic speed, the traffic flow at rush-valley hours, and the streets congestions due to the lack of parking spaces.

Yıldırım Bayazıt, Selami Yurdan Özgül

Global population growth is increasing the pressure on water resources day by day. At the same time, changes in land use, especially due to increased urbanization, affect hydrological processes. Considering both population and urbanization, the management of water resources with the right planning becomes inevitable. In this study, the worst-case scenario was handled and it was investigated how much more the city could meet its water needs if the drinking water treatment plants in the provinces of Istanbul, Ankara and Kocaeli were operating at full capacity. In the analyzes handled with the current water losses, the population projections and the future change in the per capita water need are revealed. According to the results obtained, it was determined that when the existing drinking water treatment plants in Istanbul are used at full capacity, there may be water shortages in 2039. Under the same conditions, it was determined that Ankara would not be able to meet its water needs in 2036. In Kocaeli, it was determined that in 2031, the existing facilities will be insufficient for the water demand. The results of the study showed that the necessary measures should be taken immediately for the water crisis, which is expected to be one of the most important problems of our country in the future.

Amir Reza Mamdoohi, Elnaz Irannezhad, Hamid Rezaei et al.

Pricing and traffic rationing have become popular and economically viable ways to reduce traffic congestion in major cities' central business districts (CBDs). Time-based and duration-based pricing rules affect travel behavior in Tehran, Iran's capital. To figure out the consequences, 1388 congestion pricing zone and 983 odd-even traffic rationing zone travelers were surveyed in 2018–2019. The stated preference survey and error component logit model modeled trip variations in modal shift, route choice, and time of travel in a day. A generalized mixed logit model examined mode choice behavior using revealed and stated preferences. The error component logit model suggests that the duration-based scenario will lead to a modal shift, trip alteration, and trip cancellation, whereas the time-based scenario will change the time or destination. A generalized mixed logit model and revealed and stated preference data imply that duration-based pricing is more successful than time-based pricing in shifting private vehicle trips to other modes. Also, results show public transit is the most common demand deviation, and the time-based scenario is more successful than the duration-based scenario. The mode shift to Snap is lower than other transport modes in both scenarios, suggesting that on-demand ride-hailing is a less vital competitor in zones.

Miguel Puente-Ajovín, Arturo Ramos, Fernando Sanz-Gracia

We study the parametric description of the city size distribution (CSD) of 70 different countries (developed and developing) using seven models, as follows: the lognormal (LN), the loglogistic (LL), the double Pareto lognormal (dPLN), the two-lognormal (2LN), the two-loglogistic (2LL), the three-lognormal (3LN) and the three-loglogistic (3LL). Our results show that 3LN and 3LL are the best densities in terms of non-rejections out of standard statistical tests. Meanwhile, according to the information criteria AIC and BIC, there is no systematically dominant distribution.

Fan Zhang, Arianna Salazar Miranda, Fábio Duarte et al.

The visual dimension of cities has been a fundamental subject in urban studies, since the pioneering work of scholars such as Sitte, Lynch, Arnheim, and Jacobs. Several decades later, big data and artificial intelligence (AI) are revolutionizing how people move, sense, and interact with cities. This paper reviews the literature on the appearance and function of cities to illustrate how visual information has been used to understand them. A conceptual framework, Urban Visual Intelligence, is introduced to systematically elaborate on how new image data sources and AI techniques are reshaping the way researchers perceive and measure cities, enabling the study of the physical environment and its interactions with socioeconomic environments at various scales. The paper argues that these new approaches enable researchers to revisit the classic urban theories and themes, and potentially help cities create environments that are more in line with human behaviors and aspirations in the digital age.

B. Mendybayev

In many cities worldwide, the Smart City concept is used to solve problems that ensure the city’s development. The range of technological solutions applications varies depending on the needs and capabilities of a particular city or country in general. The proverbial all-encompassing meaning of the Smart City definition is not critical; however, it allows for reasonably unambiguous identification of implementation areas and even standardization. Differences in the conditions and goals of implementation are determined by the characteristics of a particular (unique) city, public needs, or demand from citizens for more modern services, and the peculiarities of state regulation and management. In Kazakhstan, the implementation of individual Smart City initiatives began more than 10 years ago. Comprehensive goal setting was carried out in 2017 as part of the Digital Kazakhstan state programme, and a comparative rating for the cities is being calculated from 2020. The article describes and defines the challenges and limitations associated with the unbalanced development measures of Kazakhstan’s cities based on a comparative analysis of indicators that characterize the level of penetration of Smart City technologies. The article substantiates the need to adjust the national policy and change priorities for successful Smart City projects.

Janna Albrecht, Joachim Scheiner

Couples' residential decisions are based on a large variety of factors including housing preferences, family and other social ties, socialisation and residential biography (e.g. earlier experience in the life course) and environmental factors (e.g. housing market, labour market). This study examines, firstly, to what extent people stay in, return to or leave their hometown (referred to as ‘migration type’). We refer to the hometown as the place where most of childhood and adolescence is spent. Secondly, we study which conditions shape a person’s migration type. We mainly focus on variables capturing elements of the residential biography and both partners’ family ties and family socialisation. We focus on the residential choices made at the time of family formation, i.e. when the first child is born. We employ multinomial regression modelling and cross-tabulations, based on two generations in a sample of families who mostly live in the wider Ruhr area, born around 1931 (parents) and 1957 (adult children). We find that migration type is significantly affected by a combination of both partners' place of origin, both partners' parents' places of residence, the number of previous moves, level of education and hometown population size. We conclude that complex patterns of experience made over the life course, socialisation and gendered patterns are at work. These mechanisms should be kept in mind when policymakers develop strategies to attract (return) migrants.

Lei WANG, Tong ZHU

With the rapid development of digital technologies based on information and communication technology (ICT), some studies suggest that the development of the digital economy is bound to have a significant impact on energy consumption. There are also studies demonstrating from different perspectives that ICT plays an important role in improving energy efficiency. Then, will the rapid development of the digital economy lead to a sharp increase in energy demand (electricity demand), thus affecting China’s socio-economic transition to green and low-carbon development? To this end, it is of great practical significance to explore the relationship between the digital economy and energy consumption from theoretical and practical perspectives. Focusing on the issue of ICT and its impacts on energy consumption, this paper clarifies the internal influencing mechanism between ICT and energy consumption. On this basis, this paper compares and analyzes the models, methods, and data in existing studies from the aspects of measurement of ICT’s direct energy consumption, empirical research on ICT and energy consumption, and discussions on rebound effects. After a brief summary, this paper identifies their shortcomings and explores future research directions.

Ruizhi Liao, Liping Chen

In response to challenges posed by urbanization, David Bollier from the University of Southern California raised a new idea for city planning: a comprehensive network and applications of information technologies. IBM later echoed the idea and initiated its Smart Planet vision in 2008. After that, the smart city concept was quickly adopted by major cities throughout the world, and it has gradually evolved into a strategic choice by ambitious cities. This paper looks into the smart city trend by reviewing how the concept of smart city was proposed and what the essence of a smart city is. More specifically, the driving forces of the smart city development in China are investigated, and the key differences of smart cities between China and other countries are summarized. Finally, four big challenges to build future smart cities are discussed.

Manmeet Singh, Nachiketa Acharya, Sajad Jamshidi et al.

Urban downscaling is a link to transfer the knowledge from coarser climate information to city scale assessments. These high-resolution assessments need multiyear climatology of past data and future projections, which are complex and computationally expensive to generate using traditional numerical weather prediction models. The city of Austin, Texas, USA has seen tremendous growth in the past decade. Systematic planning for the future requires the availability of fine resolution city-scale datasets. In this study, we demonstrate a novel approach generating a general purpose operator using deep learning to perform urban downscaling. The algorithm employs an iterative super-resolution convolutional neural network (Iterative SRCNN) over the city of Austin, Texas, USA. We show the development of a high-resolution gridded precipitation product (300 m) from a coarse (10 km) satellite-based product (JAXA GsMAP). High resolution gridded datasets of precipitation offer insights into the spatial distribution of heavy to low precipitation events in the past. The algorithm shows improvement in the mean peak-signal-to-noise-ratio and mutual information to generate high resolution gridded product of size 300 m X 300 m relative to the cubic interpolation baseline. Our results have implications for developing high-resolution gridded-precipitation urban datasets and the future planning of smart cities for other cities and other climatic variables.

Gaode Chen, Yijun Su, Xinghua Zhang et al.

Data insufficiency problems (i.e., data missing and label scarcity) caused by inadequate services and infrastructures or imbalanced development levels of cities have seriously affected the urban computing tasks in real scenarios. Prior transfer learning methods inspire an elegant solution to the data insufficiency, but are only concerned with one kind of insufficiency issue and fail to give consideration to both sides. In addition, most previous cross-city transfer methods overlook inter-city data privacy which is a public concern in practical applications. To address the above challenging problems, we propose a novel Cross-city Federated Transfer Learning framework (CcFTL) to cope with the data insufficiency and privacy problems. Concretely, CcFTL transfers the relational knowledge from multiple rich-data source cities to the target city. Besides, the model parameters specific to the target task are firstly trained on the source data and then fine-tuned to the target city by parameter transfer. With our adaptation of federated training and homomorphic encryption settings, CcFTL can effectively deal with the data privacy problem among cities. We take the urban region profiling as an application of smart cities and evaluate the proposed method with a real-world study. The experiments demonstrate the notable superiority of our framework over several competitive state-of-the-art methods.

Geoff Boeing, Carl Higgs, Shiqin Liu et al.

Benchmarking and monitoring urban design and transport features is critical to achieving local and international health and sustainability goals. However, most urban indicator frameworks use coarse spatial scales that only allow between-city comparisons or require expensive, technical, local spatial analyses for within-city comparisons. This study developed a reusable open-source urban indicator computational framework using open data to enable consistent local and global comparative analyses. We demonstrate this framework by calculating spatial indicators - for 25 diverse cities in 19 countries - of urban design and transport features that support health and sustainability. We link these indicators to cities' policy contexts and identify populations living above and below critical thresholds for physical activity through walking. Efforts to broaden participation in crowdsourcing data and to calculate globally consistent indicators are essential for planning evidence-informed urban interventions, monitoring policy impacts, and learning lessons from peer cities to achieve health, equity, and sustainability goals.

Thomas Louail, Marc Barthelemy

Characterizing the spatial organization of urban systems is a challenge which points to the more general problem of describing marked point processes in spatial statistics. We propose a non-parametric method that goes beyond standard tools of point pattern analysis and which is based on a mapping between the points and a "dominance tree", constructed from a recursive analysis of their Voronoi tessellation. Using toy models, we show that the height of a node in this tree encodes both its mark and the structure of its neighborhood, reflecting its importance in the system. We use historical population data in France (1876-2018) and the US (1880-2010) and show that the method highlights multiscale urban dynamics experienced by these countries. These include non-monotonous city trajectories in the US, as revealed by the evolution of their height in the tree. We show that the height of a city in the tree is less sensitive to different statistical definitions of cities than its rank in the urban hierarchy. The method also captures the attraction basins of cities at successive scales, and while in both countries these basin sizes become more homogeneous at larger scales, they are also more heterogeneous in France than in the US. Finally, we introduce a simple graphical representation - the height clock - that monitors the evolution of the role of each city in its country.

Niran Adhikari, D. Subedi

Dengue is a mosquito-borne viral infection. Since the first reported incidence in 2004, several sporadic outbreaks of dengue have been recorded from both tropical and subtropical regions of Nepal, including the capital city Kathmandu. However, in the last 5 years, the incidence of dengue cases has risen alarmingly. The largest-ever outbreak was reported in 2019, which killed six people. The global warming, unplanned urbanization, increased transportation, and lack of efficient mosquito control are presumably associated with the spread of dengue and its vector to the plane and hilly regions of this country. With the ongoing Nepalese government campaign “Visit Nepal Year 2020” to attract two million tourists in mind, effective dengue control measures must be implemented to control potential future outbreaks.

P. deSouza