Dense City Research Articles

Expanding urban green space with superblocks

The Barcelona superblock is an urban neighbourhood transformation strategy, with which car-based traffic is redirected away from streets that are inside a 3 × 3 urban block configuration. This urban design concept promises opportunities for alternative street use such as the transformation of street space into urban green space. The potential to foster urban green space due to superblock design is however unclear, particularly outside of the original Barcelonan context. Concerning urban densification, fostering urban green space is particularly relevant to achieving dense and green cities. In this study, potential superblocks are identified in all major Swiss cities and the current urban green space is quantified. This analysis reveals distinct differences of superblock opportunities and urban green space between different cities and allows pinpointing opportunities for expanding urban green space. Considering the nine largest Swiss cities, between 3% and 18% of the current street network was simulated to be potentially suitable for superblock implementation to transform the streetscape and increase urban green space. The variation of current urban green space coverage across all potential individual superblock sites that have high urban density ranges considerably from a few percentages to above 30%. The presented results allow the exploration of urban green space opportunities at street and block-level arising from superblocks in Switzerland. For example, when considering a citywide superblock implementation scenario, the potential street area is relatively high for Basel whilst at the same time showing relatively low current availability of urban green space. For creating detailed design or transformation strategies based on the explored superblock sites, more integrated analysis to evaluate potential benefits as well as disservices of such urban transformation is required.

Estimation of the Efficiency of Vessel Speed Reduction to Mitigate Gas Emission in Busan Port Using the AIS Database

To mitigate marine atmospheric pollution causing greenhouse gas (GHG) and a threat to coastal residents’ health in dense hub port cities, the Vessel Speed Reduction (VSR) programs were implemented in the Republic of Korea. Spatial analysis of the efficiency of the VSR programs is essential to monitor and improve the present programs. In the present study, the efficiency of the VSRs from the Busan Port (BP), including North Port (NP) and Gamcheon Port (GP), were analyzed. A bottom-up activity-based approach using automatic identification system (AIS) data was introduced herein for the estimation of spatial marine gas emission in real time. The BP has implemented the VSR program since 2020; thus, this study spatially analyzed marine gas emissions in the areas in 2019 and 2020 to demonstrate the efficiency of VSR. To demonstrate the VSR programs in the aspect of the comparison of gas emissions in each year, the total annual fuel consumption in each year is divided by the total arrival ships’ GT respectively. According to the comparison of the spatial gas emission inventory between two years in the designed area, 19.2% of the annual marine gas emissions per ships’ GT in BP in 2020 were reduced with the implementation of the VSR program. The spatial analysis clearly showed the mitigation of the ships’ gas emissions along the passageway to BP. The spatial analysis of the efficiency of the VSR program will be useful basic data to reflect the local gas emission state on the improvement of the VSR program and newly established environmental regulations.

Users’ views on cultural ecosystem services of urban parks: An importance-performance analysis of a case in Beijing, China

Rapid urbanisation and global climate change have had a profound impact on the development of cities. Nature-based solutions, such as urban parks in dense city areas, play an important role in addressing such problems. They provide cultural ecosystem services to improve human well-being. Scholars have studied the cultural ecosystem services provided by urban parks from the perspective of users. Insufficient research, however, has addressed differences in perceptions of cultural ecosystem services among different social groups, as well as the relationship between the supply and demand of cultural ecosystem services. In this study, based on face-to-face questionnaire surveys and interviews, we analysed users’ perceptions of cultural ecosystem services in an urban park in Wudaokou, a multifunctional area in the centre of Beijing, China. The study pioneers the application of importance–performance analysis, a method to systematically analyse users’ perceptions of the importance and performance of the cultural ecosystem services of urban parks. We found significant differences in perceptions of importance, and the importance scores overall were significantly higher than the performance scores. Users’ perceptions of performance were affected by spatial identity source attribute and age: residents living nearby appreciated the performance more than commuters and passers-by; young people gave the highest scores. The importance–performance analysis approach offers a mechanism to help policymakers and planners match peoples’ needs with cultural ecosystem service provision.

Urban microclimate and energy consumption: A multi-objective parametric urban design approach for dense subtropical cities

Climate change within the urban contexts is a crisis that cities are confronting globally. This issue poses numerous negative consequences such as thermal discomfort and increased energy usage within the building sector. This is especially the case in Western Sydney, Australia, where the average maximum temperature has risen by 7–8 °C within the past 30 years. This increase in temperature is highly concerning, since this region is witnessing rapid urban and infrastructural development and is proposed as the third-largest economy of Australia. Temperature changes in this region will also result in considerably increasing the electricity used for cooling purposes. This paper presents a parametric approach driven multi-objective optimization methodology to discover optimum design solution based on the urban microclimate and cooling energy demand of multi-functional buildings within this urban context. Mitigation measures including a range of design factors at both building (typology and window to wall ratio) and urban scales (aspect ratio and urban grid rotation) are further suggested for developing context sensitive optimum urban layouts. The resultant solutions indicate an improvement in urban thermal comfort, cooling and heating energy use by up to 25.85%, 72.76%, and 93.67%, respectively.

Identifying urban ventilation corridors through quantitative analysis of ventilation potential and wind characteristics

Urban heat islands (UHIs) are mainly caused by mismanaged urban development. Urban ventilation corridors (UVCs) can effectively reduce UHIs. Hangzhou, a large, dense city in eastern China, is one of the nation's hottest cities and must urgently improve its ventilation. In this study, a newly developed method combining land surface temperature retrieval, GIS spatial analysis, and weather data was employed to design city-level UVCs. The functional space and compensation space of UVCs are identified based on the LandsatETM8 image data inversion of surface temperature. The contribution of affect factors, such as building density, building height, green land area, waterbody, roads, and urban terrain, to the urban ventilation potential is calculated using AHP and GIS. Areas with tremendous ventilation potential were identified as possible ventilation corridors by using an evaluation model and considering wind characteristics. Fifty-four high-temperature zones and 48 low-temperature zones were identified as functional and compensative spaces in Hangzhou, respectively. On the urban scale, green space (area >500ha), water bodies (area >300ha or width >100 m), and roads (width >50 m) were considered to be the factors that have the greatest impact on urban ventilation potential. The LCP method was used to verify the accuracy and rationality of the method proposed in this study to determine the city-scale UVC. UVC planning schemes and construction measures were proposed to provide rich information and a reference basis for the new general land and space planning of Hangzhou. However, to improve the accuracy of the potential ventilation results, the urban underlying surface criteria should be re-evaluated more comprehensively.

Barcelona under the 15-Minute City Lens: Mapping the Accessibility and Proximity Potential Based on Pedestrian Travel Times

Many academics, urban planners and policymakers subscribe to the benefits of implementing the concept of the 15-Minute City (FMC) in metropolises across the globe. Despite the interest raised by the concept, and other variants of chrono-urbanism, to date, only a few studies have evaluated cities from the FMC perspective. Most studies on the subject also lack a proper well-defined methodology that can properly assess FMC conditions. In this context, this study contributes to the development of an appropriate FMC-measuring method by using network analysis for services and activities in the City of Barcelona (Catalonia, northeastern Spain). By using network analyst and basing our analysis on cadastral parcels, this study is able to detail the overall accessibility conditions of the city and its urban social functions based on the FMC perspective. The resulting spatial synthetic index is enhanced with the creation of partial indexes measuring the impact of education, provisioning, entertainment, public and non-motorized transport, and care facilities. The results show that most residents of this dense and compact city live in areas with proximity to services, that can clearly be labeled as FMC, although there are some shortfalls in peripheral areas. Results validate the FMC methodology as a viable method to highlight spatial inequalities at the microscale level, a valuable tool for the development of effective planning policies.

From sparse to compact city – shifting notions of nature in post-war residential landscapes in the Helsinki region

ABSTRACT Different urban models, ranging from sparse garden cities to dense compact cities, have aimed to achieve healthy environments and combat the disadvantages of the city. They have aspired to respond to the specific challenges of each era, although, the means have substantially varied. Shifting ideologies have materialized in urban models but also in landscape architecture – a field that has remained largely unexamined in urban planning history. This article highlights the role of landscape architecture – urban greenery, parks, and gardens – and the ideals of urban nature they entail. The focus is on post-war residential landscapes in the Helsinki region, Finland in the 1950s–2010s. The article analyses the changing planning paradigms of urban nature with five city types: the garden city, forest city, compact city, ecological city, and the new compact city. Each paradigm has its specific nature type, which is characterized by different meanings and spatial forms given to nature, the ideal environment and the appropriate density. The study brings a landscape architecture approach to the academic discussion on the role of urban nature in urban planning. It also offers a critical outlook, reminding that the discussion on nature is not neutral and straightforward, but contradictory and loaded with underlying meanings.

Validation of a Japanese walkability index using large-scale step count data of Yokohama citizens

In Japan where the population is aging and declining, it is necessary to evaluate and improve the walkability of cities. However, it may not be appropriate to use the indices developed for American cities in highly dense cities in Asia. This study aimed to verify the association of a newly developed walkability index, which quantifies the accessibility of various urban amenities, with step counts of Yokohama citizens (n = 54,698). Participants were categorized into four subgroups according to sex and age. Scores from both the new and an existing index were calculated for each participant's neighborhood. Using generalized linear mixed models, associations of the scores with their step counts (count models) and probability of target achievement (binomial models) were examined. Overall, the new index predicted citizens' step counts better than the existing index in both models. The new index had a stronger association with step count in older adults in the count models and with target achievement in women in the binomial models. The findings support the efficacy of the new index, which indexes various amenities instead of density variables, in assessing the walkability in highly dense cities, as well as the need for indices tailored to the urban context.

Covid 19 vaccination: Accessibility or literacy? Israel as a case study

Israel is ranked as the leading country in terms of prevalence of vaccination against SARS-COV-2 virus (persons vaccinated divided by total population). Based on updated data as of January 19, 2021, the objective of the current study is to assess the relationship between the prevalence of vaccination and population density. A-priori, given the better infrastructure of health services (more physicians and nurses per 1000 persons), one would anticipate a higher level of vaccination in denser cities. Surprisingly, the outcomes demonstrate an opposite relationship: a lower level in the per capita level of vaccination with higher population densities from 0.2144 for 2 persons per sq. Km. to a minimum of 0.007191 for 16,642 persons per sq. Km. Given the relatively good accessibility to vaccination centers and high spread of clinics and health centers in Israel, research findings thus stress the major importance of promoting the benefits of vaccination (vaccination literacy) to diversified populations.

Dense and Proximate Development—Daylight in the Downtown Area of a Compact City

Daylight is of utmost importance and should be the main source of light in most areas dedicated to working and living. When considering our contemporary way of living, it can be easily discerned that most of our life is spent indoors, yet in a typical architectonic design approach, daylight is too often hardly of consequence. Hence daylight becomes a critical factor. Designers comply with the legal requirements of the solar hours required for areas subjected to constant use. Simultaneously for electrical engineers’ daylight is only an additional source of light valued only where energy efficiency is concerned. The basic idea of this research is to, starting from the concept level, design the building’s volume in line with energy efficiency requirements and user expectations using daylight access strategy as the main parameter. This scope of research has been a subject of various scientific theses conducted within the last years at the Faculty of Architecture Warsaw University of Technology. This paper is dedicated to the latest and most developed outcomes. The presented solution is an architectonic point of view dedicated to the use of the daylight factor in office areas located in a dense city district that may support efficient energy requirements, including the requirements of the electric lighting system. Illumination values were set according to the BREEAM daylight and PN-EN 17037 Daylight of Buildings standard. The presented strategy is unconventional for Poland, but has the potential to be included in practice and should be developed further, together with electrical engineers, as a part of energy-saving solutions. Possibly, it should be followed simultaneously with the development of the compact cities ideas. It is hoped that it might be a starting point for discussion, and for a more detailed interdisciplinary research in the future.

Analysis of Road Performance and the impact of Development in Pasar Minggu, Jakarta

The city of South Jakarta is a dense metropolitan city because it has a high population growth rate. Due to this population growth, the city of South Jakarta has experienced additions, expansion of social facilities and infrastructure as well as transportation to serve the needs of its residents, one of which is the Lenteng Agung-West Tanjung Flyover Development Project. The infrastructure built has an impact on traffic congestion on the performance of the Lenteng Agung-Tanjung Barat road and Pasar Minggu intersection. The purpose of this study is to determine road performance and to know strategies that can be used to overcome the impact of traffic congestion. The method used in this analysis and discussion is based on the Indonesian Road Capacity Manual (MKJI), 1997 and conducts a field survey for the performance of roads and intersections without signals. The results of the research obtained on the performance of the Unmarked Intersection road are the largest traffic volume of the Unmarked Intersection which is obtained from the survey results on Friday 18 December 2020 and the peak hours are at 06.30-07.30 WIB With the degree of saturation DS = 0.66, the delay at the intersection is 10.85 sec / pcu and the chances of queuing are 36.97% -17.96%. In the analysis of the Lenteng Agung road section, the highest level of service was obtained on Monday, November 16 2020 in the morning at 07: 30-08.30, with a degree of saturation of 0.98 having a service level of E, which means the flow is unstable. Meanwhile, in the afternoon, 16: 00-18: 30 with a saturation degree of 0.53 and has a service level of B.

The effects of visual landscape and traffic type on soundscape perception in high-rise residential estates of an urban city

In dense urban cities with high-rise estates where large population of residents live in close proximity, the increasing noise exposure in soundscapes due to traffic noise, construction and other undesirable anthropophony in urban lived environments may cause adverse effects on the wellbeing of residents. In this study, soundscapes around such urban spaces are investigated using Singapore as a case study. This study aims to discover the current conditions of soundscapes around such spaces and whether traffic and landscape features have a sizeable effect on soundscape perception, as well as to develop a predictive model using soundscape indicators based on acoustics, psychoacoustics, and audio features. The results show that the soundscapes in the selected urban city’s heartlands are generally dominated by traffic (40%) and biophonic (36%) sources. This study identifies the significant effects of both traffic conditions and landscape features that affect soundscape perception. A predictive model is developed based on identified objective indicators and an alternate method to derive the total mask duration of positive sound events. The visibility of roadways and vehicles correlates negatively with soundscape perception and reaffirms the effects of road visibility on noise annoyance. However, light traffic conditions do not adversely affect the soundscape perception as compared to heavy traffic, suggesting tolerance for light traffic by the participants in residential settings. Thus, the present study recommends that urban planners should take into consideration the type of traffic infrastructure when planning residential developments.

Unmapping green space

In this article, we study the ongoing redevelopment of post-war, modernist residential area Rosengård, located in Sweden’s third biggest city Malmö. We show how a planning and design strategy for this area has come to focus on a ‘compact city’ typology in line with Malmö’s strategy for creating a ‘near, dense, green and mixed city’. Such compact city typology emphasizes high density, urbanity, proximity and mixed-use as key values for renewal, but also threatens the green spaces in areas designated for densification. This article illustrates how renewal plans for modernist residential areas with generous green space provision also ensure dispossession of residents’ rights to green space. Our analysis highlights how this planned dispossession is preceded by a discursive dispossession carried out by the way urban planning represents these spaces. The Rosengård case illustrates how a compact city vision imposed on marginalized modernist areas co-emerges with new forms of expert knowledge which both ‘unmaps’ existing green spaces and defines them as problematic and requiring interventions. The article highlights the important, but not yet sufficiently explored, dispossession of the right to public green space in racialized poor peripheries of Northern cities already facing intense displacement pressure. We argue that this type of renewal of modernist areas not only tends to neglect mapping important public spaces and uses of space, but actively produces blind spots by deploying a compact city planning epistemology which necessarily undermines rights to green space in the city and should put into question the compact city as the default sustainability fix.

Methodology and parameters to analyse daylighting and energy use in dense cities: A literature review

Low energy buildings are key to reduce global energy use. However, achieving low energy use and good daylight levels simultaneously in dense cities is challenging. This article reviews relevant studies dealing with energy use and daylighting in dense residential urban blocks located in Nordic climates. The literature review combines a systematic and a ‘snowball’ search approach. Findings indicate that previous research relies heavily on parametric design as a tool. Few density metrics were found particularly relevant to describe the interplay between density, daylight, and energy use. However, the limited body of research achieved so far in the Nordic climate makes it difficult to draw a clear conclusion, suggesting that additional research is required.

Sustainable Cities: Reconsidering China’s Urban Residential Policies

Rapid urbanization, especially in developing countries, means that the worldwide tradition of low-rise housing is giving way to living in urban apartments. This implies huge environmental and sociocultural changes. For sustainability, dense and high-rise cities offer some advantages, but negative aspects too, especially for residential areas and low-income groups. A widespread residential model, in China and elsewhere, is high-rise urban “superblocks”. However, equally high population densities can be achieved in several ways, including quite low-rise, with equal energy efficiency as well as other environmental and social qualities. Building on analyses of some urban blocks in Ningbo, China, we explore current trends and assess options for sustainable living in future urban residential areas. This paper delves into ten key points related to the overarching goals of sustainable and low carbon-cities. In particular, the arguments support low-dense urban design paradigms against high-rise urban superblocks. By exploring the case of Ningbo, China, we map some existing urban residential typologies and compounds. Through a comparative analysis, the study then focuses on key factors for reconsidering China’s urban residential policies, and towards sustainable city paradigms.

Der Heilige Quirinus von Siscia und der Heilige Martin in Savaria/Stein am Anger/Szombathely

The present article not only traces the life of the two Pannonian saints Quirinus and Martin in ancient Savaria, but also demonstrates their presence in the modern city of Szombathely. Unfortunately, many questions remain unanswered, such as the translation of Quirinus to Rome or the localisation of a basilica at the porta Scarabatensis. A German translation of the Acta Beati Quirini Episcopi et Martyris is presented for the first time (in the appendix). St. Martin’s birthplace cannot be located in the cemetery extra muros, which is why the walls found under the apse of St. Martin’s Chapel by I. Paulovics are probably not the remains of the house where St. Martin was born, but ruther the remnant of the Basilica of Quirinus. In spite of the dense city population today, one can only hope for future excavations.

The Topodiverse City: Urban Form for Subjective Well-Being

Research is now better than ever able to unveil how urban inhabitants’ movement, behavior and experiences relate to the urban forms in which they take place. Consequently, urban form might increasingly be able to function as a focal point for different strands of research that focus on sustainable urban life, and as a link between research and planning practice through the development of empirically informed design principles. Drawing on literature from urban morphology, complex systems analysis, environmental psychology, and neuroscience, I provide a wide-angle view of how urban form relates to subjective well-being through movement, social and economic activity, experiences and psychological restoration. I propose three principles for urban form that could promote subjective well-being while also mitigating the environmental impact of cities in industrialized societies. The principles revolve around so-called topodiversity, meaning variation across an urban area in spatial conditions that allows subjective well-being to be promoted through several different pathways. The principles together suggest an urban form that I call the topodiverse city. The topodiverse city displays a polycentric structure and is more spatially contained than the sprawling city, yet not as compact as the dense city. I also propose indicators to measure the principles using mostly openly available data and analysis methods, to further research on how urban form can enable urban subjective well-being with low environmental impact.

Reconnecting Spatialities in Uninhabited Industrial Spaces: Ruination and Sense of Place in a Coal Town (Datong, Shanxi

Far from dense Chinese cities that experience fast demolition, ruination in Kouquan, a coal town in Datong, is a slower process that generates new practices and meanings. Uninhabited industrial spaces continue to produce a sense of place where large industrial corporations no longer operate and where most residents have moved away. This article brings out new perspectives on the effects of ruination in an industrial area by moving away from the lenses of the work unit, demolition, heritagisation, or decline. Based on direct observation, informal discussions with local residents from 2016 to 2019, and an online review, this article shows that ruination produces spatialised narratives and practices closely entwined with the local population’s experiences, as well as with other actors’ direct and indirect interactions with places: these actors reconnect to the uninhabited town through dwellings, artistic production, religious practices, or simply through their visits to Kouquan, becoming urban explorers themselves. Ruination leads remaining residents, former locals, visitors, government actors, journalists, and artists to the production of new representations of the uninhabited town.

The effect of the Mongol invasion on the townscape of Iranian cities

PurposeThe Mongol invasion caused widespread destruction in many cities; this research studies the destruction course of cities after the Mongol invasion and their reconstruction during the reform period, the change that it brought to the cityscapes of Iranian cities and the difference between the urbanscape of the cities that flourished or were re-established after these destructions with the cities prior to them.Design/methodology/approachThe method of research used is historical interpretation/analysis. The historical texts of pre-Mongolian Persia and texts from the Ilkhanid era are studied, references to the shapes and appearances of Iranian cityscapes are classified, and with the help of contemporary interpretations and existing physical evidence, the urbanscape of these two periods are redrawn and compared to each other.FindingsThe selection of scenic meadows to build the city, the presence of many gardens in the urban patterns and the construction of satellite towns around large cities have been the effects of the Mongol tradition of (Yurt) tent-dwelling on Iranian cities during the reforms. The declining population and the massive migration of artists together with the rethinking of the rulers made the existence of dense cities with multi-storey houses less likely. The tradition of pre-designing the city and buildings and designing open and right-angled pathways continued after the Mongol invasion.Originality/valueThe prevailing belief is that during the Mongol era, only the destruction of cities took place and the Mongols did not create any cities and had no influence on urban development. This research aims to challenge that.

Activity-based epidemic propagation and contact network scaling in auto-dependent metropolitan areas

We build on recent work to develop a fully mechanistic, activity-based and highly spatio-temporally resolved epidemiological model which leverages person-trajectories obtained from an activity-based model calibrated for two full-scale prototype cities, consisting of representative synthetic populations and mobility networks for two contrasting auto-dependent city typologies. We simulate the propagation of the COVID-19 epidemic in both cities to analyze spreading patterns in urban networks across various activity types. Investigating the impact of the transit network, we find that its removal dampens disease propagation significantly, suggesting that transit restriction is more critical for mitigating post-peak disease spreading in transit dense cities. In the latter stages of disease spread, we find that the greatest share of infections occur at work locations. A statistical analysis of the resulting activity-based contact networks indicates that transit contacts are scale-free, work contacts are Weibull distributed, and shopping or leisure contacts are exponentially distributed. We validate our simulation results against existing case and mortality data across multiple cities in their respective typologies. Our framework demonstrates the potential for tracking epidemic propagation in urban networks, analyzing socio-demographic impacts and assessing activity- and mobility-specific implications of both non-pharmaceutical and pharmaceutical intervention strategies.