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Urban areas have interaction characteristics that favor the spread of the Covid-19 pandemic. The lifestyle of urban communities with higher close contact influences the speed of the spread of Covid19, which makes cities play an important role in the transmission of Covid19. Surgo Ventures' Covid19 Community Vulnerability Index variable is used to analyze the community vulnerability in Surakarta Greater Urban. Statistics from government agencies were used to collect data on population, heterogeneity, housing conditions, health care systems, and environmental risks, which were then analyzed in the sub-district spatial unit. The findings show a close correlation between the aggregate value of the Covid19 Community Vulnerability Index (CCVI) and the rate of spread of Covid19 both in the city center and the urban fringe. However, the variable with the strongest correlation in the urban area differs from the variable in the urban fringe area. Furthermore, there are differences in vulnerability in urban communities. This demonstrates the need for different Covid19 handling strategies in different communities, despite the fact that they are all part of the same urban service system. The identification of these determinants may subsequently contribute to the design of cities that are better prepared for future pandemics.
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The sediments underneath Mexico City have unique mechanical properties that give rise to strong site effects. We investigated temporal changes in the seismic velocity at strong-motion and broadband seismic stations throughout Mexico City, including sites with different geologic characteristics ranging from city center locations situated on lacustrine clay to hillside locations on volcanic bedrock. We used autocorrelations of urban seismic noise, enhanced by waveform clustering, to extract subtle seismic velocity changes by coda wave interferometry. We observed and modeled seasonal, co- and post-seismic changes, as well as a long-term linear trend in seismic velocity. Seasonal variations can be explained by self-consistent models of thermoelastic and poroelastic changes in the subsurface shear wave velocity. Overall, sites on lacustrine clay-rich sediments appear to be more sensitive to seasonal surface temperature changes, whereas sites on alluvial and volcaniclastic sediments and on bedrock are sensitive to precipitation. The 2017 Mw 7.1 Puebla and 2020 Mw 7.4 Oaxaca earthquakes both caused a clear drop in seismic velocity, followed by a time-logarithmic recovery that may still be ongoing for the 2017 event at several sites or that may remain incomplete. The slope of the linear trend in seismic velocity is correlated with the downward vertical displacement of the ground measured by interferometric synthetic aperture radar, suggesting a causative relationship and supporting earlier studies on changes in the resonance frequency of sites in the Mexico City basin due to groundwater extraction. Our findings show how sensitively shallow seismic velocity and, in consequence, site effects react to environmental, tectonic and anthropogenic processes. They also demonstrate that urban strong-motion stations provide useful data for coda wave monitoring given sufficiently high-amplitude urban seismic noise.
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Volatile organic compounds (VOCs) have direct influences on air quality and climate. They indeed play a key role in atmospheric chemistry as precursors of secondary pollutants, such as ozone (O3) and secondary organic aerosols (SOA). In this respect, long-term datasets of in situ atmospheric measurements are crucial for characterizing the variability of atmospheric chemical composition, its sources, and trends. The ongoing establishment of the Aerosols, Cloud, and Trace gases Research InfraStructure (ACTRIS) allows implementation of the collection and provision of such high-quality datasets. In this context, online and continuous measurements of O3, nitrogen oxides (NOx), and aerosols have been carried out since 2012 at the SIRTA (Site Instrumental de Recherche par Télédétection Atmosphérique) observatory, located in the Paris region, France. Within the last decade, VOC measurements were conducted offline at SIRTA, until the implementation of real-time monitoring which started in January 2020 using a proton-transfer-reaction quadrupole mass spectrometer (PTR-Q-MS).The dataset acquired during the first 2 years of online VOC measurements provides insights into their seasonal and diurnal variabilities. The additional long-term datasets obtained from co-located measurements (NOx, aerosol physical and chemical properties, meteorological parameters) are used to better characterize the atmospheric conditions and to further interpret the obtained results. Results also include insights into VOC main sources and the influence of meteorological conditions and air mass origin on their levels in the Paris region. Due to the COVID-19 pandemic, the year 2020 notably saw a quasi-total lockdown in France in spring and a lighter one in autumn. Therefore, the focus is placed on the impact of these lockdowns on the VOC variability and sources. A change in the behaviour of VOC markers for anthropogenic sources was observed during the first lockdown, reflecting a change in human activities. A comparison with gas chromatography data from the Paris city centre consolidates the regional representativity of the SIRTA station for benzene, while differences are observed for shorter-lived compounds with a notable impact of their local sources. This dataset could be further used as input for atmospheric models and can be found at 10.14768/f8c46735-e6c3-45e2-8f6f-26c6d67c4723 (Simon et al., 2022a).
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Nitrogen dioxide (NO2) air pollution provides valuable information for quantifying NOx (NOx = NO + NO2) emissions and exposures. This study presents a comprehensive method to estimate average tropospheric NO2 emission strengths derived from 4-year (May 2018–June 2022) TROPOspheric Monitoring Instrument (TROPOMI) observations by combining a wind-assigned anomaly approach and a machine learning (ML) method, the so-called gradient descent algorithm. This combined approach is firstly applied to the Saudi Arabian capital city of Riyadh, as a test site, and yields a total emission rate of 1.09×1026 molec. s-1. The ML-trained anomalies fit very well with the wind-assigned anomalies, with an R2 value of 1.0 and a slope of 0.99. Hotspots of NO2 emissions are apparent at several sites: over a cement plant and power plants as well as over areas along highways. Using the same approach, an emission rate of 1.99×1025 molec. s-1 is estimated in the Madrid metropolitan area, Spain. Both the estimate and spatial pattern are comparable with the Copernicus Atmosphere Monitoring Service (CAMS) inventory.Weekly variations in NO2 emission are highly related to anthropogenic activities, such as the transport sector. The NO2 emissions were reduced by 16 % at weekends in Riyadh, and high reductions were found near the city center and in areas along the highway. An average weekend reduction estimate of 28 % was found in Madrid. The regions with dominant sources are located in the east of Madrid, where residential areas and the Madrid-Barajas airport are located. Additionally, due to the COVID-19 lockdowns, the NO2 emissions decreased by 21 % in March–June 2020 in Riyadh compared with the same period in 2019. A much higher reduction (62 %) is estimated for Madrid, where a very strict lockdown policy was implemented. The high emission strengths during lockdown only persist in the residential areas, and they cover smaller areas on weekdays compared with weekends. The spatial patterns of NO2 emission strengths during lockdown are similar to those observed at weekends in both cities. Although our analysis is limited to two cities as test examples, the method has proven to provide reliable and consistent results. It is expected to be suitable for other trace gases and other target regions. However, it might become challenging in some areas with complicated emission sources and topography, and specific NO2 decay times in different regions and seasons should be taken into account. These impacting factors should be considered in the future model to further reduce the uncertainty budget.
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Cities experience rapid growth and transformation. Over the past decades, change has been particularly intense and complex, associated to globalization, spatial compression and temporal acceleration. Within this context, the EU funds introduced new urban rehabilitation dynamics that made a city center more and more attractive. This, alongside the growth of international tourism, has increased the number of city users, which has furthered the discussion on the relation between the physical, economic, social and environmental intervention of the city, as well as the debates on the positive and negative impacts of tourism in cities. With that in mind, we look at the intense change that occurred in the city of Porto, Portugal, in the period from an intense economic crisis to the COVID-19 confinement. We consider changes in buildings, retail and policies to conclude that a neoliberal attitude favoured a tourism-led and sustainability blind gentrification. Based on a survey and analysis of 50 urban rehabilitation initiatives in downtown Porto and on the analysis of recent public policies, we discuss the relation between urban rehabilitation and tourism in Porto, and therefore the effectiveness of public policies and its contribution to sustainable urban development.
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In orbit since late 2017, the Tropospheric Monitoring Instrument (TROPOMI) is offering new outstanding opportunities for better understanding the emission and fate of nitrogen dioxide (NO2) pollution in the troposphere. In this study, we provide a comprehensive analysis of the spatio-temporal variability of TROPOMI NO2 tropospheric columns (TrC-NO2) over the Iberian Peninsula during 2018–2021, considering the recently developed Product Algorithm Laboratory (PAL) product. We complement our analysis with estimates of NOx anthropogenic and natural soil emissions. Closely related to cloud cover, the data availability of TROPOMI observations ranges from 30 %–45 % during April and November to 70 %–80 % during summertime, with strong variations between northern and southern Spain. Strongest TrC-NO2 hotspots are located over Madrid and Barcelona, while TrC-NO2 enhancements are also observed along international maritime routes close the strait of Gibraltar, and to a lesser extent along specific major highways. TROPOMI TrC-NO2 appear reasonably well correlated with collocated surface NO2 mixing ratios, with correlations around 0.7–0.8 depending on the averaging time.We investigate the changes of weekly and monthly variability of TROPOMI TrC-NO2 depending on the urban cover fraction. Weekly profiles show a reduction of TrC-NO2 during the weekend ranging from -10 % to -40 % from least to most urbanized areas, in reasonable agreement with surface NO2. In the largest agglomerations like Madrid or Barcelona, this weekend effect peaks not in the city center but in specific suburban areas/cities, suggesting a larger relative contribution of commuting to total NOx anthropogenic emissions. The TROPOMI TrC-NO2 monthly variability also strongly varies with the level of urbanization, with monthly differences relative to annual mean ranging from -40 % in summer to +60 % in winter in the most urbanized areas, and from -10 % to +20 % in the least urbanized areas. When focusing on agricultural areas, TROPOMI observations depict an enhancement in June–July that could come from natural soil NO emissions. Some specific analysis of surface NO2 observations in Madrid show that the relatively sharp NO2 minimum used to occur in August (drop of road transport during holidays) has now evolved into a much broader minimum partly de-coupled from the observed local road traffic counting;this change started in 2018, thus before the COVID-19 outbreak. Over 2019–2021, a reasonable consistency of the inter-annual variability of NO2 is also found between both datasets.Our study illustrates the strong potential of TROPOMI TrC-NO2 observations for complementing the existing surface NO2 monitoring stations, especially in the poorly covered rural and maritime areas where NOx can play a key role, notably for the production of tropospheric O3.
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This paper describes two studies that aimed to explore the impacts of pedestrianisation or road closures on traffic displacement, travel behaviour and the phenomenon of ‘disappearing traffic'. The first study surveyed residents whose travel routes were affected by a small-scale localised pedestrianisation scheme in the centre of a town. The second measured the traffic impacts of a temporary closure of a strategic bridge in a city centre. In the first case, the pedestrianisation produced no change in the modal shares of travel of residents. Drivers continued to drive to the same locations by longer routes. In the second case, the closure caused some traffic displacement and increased journey times but also reduced traffic volumes in both the immediate area and across the city. This paper concludes by discussing the remaining knowledge gaps on disappearing traffic, made more pressing by the decisions of authorities to reallocate road space during the coronavirus disease 2019 crisis.
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During a pandemic, residents of tourism destinations face the dilemma of whether to welcome tourists to help the economy rebound or to oppose their arrival to minimize the risk of contagion. This paper examines the influence of residents' perception of the economic crisis triggered by the pandemic and the health risks associated with tourist arrivals on their attitudes towards tourism impacts and willingness to support tourism development. To this end, a novel model is tested using structural equation modelling (SEM). The potential moderating effect of belonging to certain population groups is also analysed, namely (i) having a household member linked to the tourism sector, (ii) residing in the city centre, and (iii) belonging to a COVID-19 risk group. Perceived risk of contagion was found to be a stronger predictor of residents' support for tourism development than perception of the economic crisis;an effect that increases notably among residents of the most popular tourist areas of the city. These empirical findings provide useful information with a view to designing destination planning strategies during and after the pandemic.
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We present the CarbonTracker Europe High-Resolution (CTE-HR) system that estimates carbon dioxide (CO2) exchange over Europe at high resolution (0.1 × 0.2∘) and in near real time (about 2 months' latency). It includes a dynamic anthropogenic emission model, which uses easily available statistics on economic activity, energy use, and weather to generate anthropogenic emissions with dynamic time profiles at high spatial and temporal resolution (0.1×0.2∘, hourly). Hourly net ecosystem productivity (NEP) calculated by the Simple Biosphere model Version 4 (SiB4) is driven by meteorology from the European Centre for Medium-Range Weather Forecasts (ECMWF) Reanalysis 5th Generation (ERA5) dataset. This NEP is downscaled to 0.1×0.2∘ using the high-resolution Coordination of Information on the Environment (CORINE) land-cover map and combined with the Global Fire Assimilation System (GFAS) fire emissions to create terrestrial carbon fluxes. Ocean CO2 fluxes are included in our product, based on Jena CarboScope ocean CO2 fluxes, which are downscaled using wind speed and temperature. Jointly, these flux estimates enable modeling of atmospheric CO2 mole fractions over Europe.We assess the skill of the CTE-HR CO2 fluxes (a) to reproduce observed anomalies in biospheric fluxes and atmospheric CO2 mole fractions during the 2018 European drought, (b) to capture the reduction of anthropogenic emissions due to COVID-19 lockdowns, (c) to match mole fraction observations at Integrated Carbon Observation System (ICOS) sites across Europe after atmospheric transport with the Transport Model, version 5 (TM5) and the Stochastic Time-Inverted Lagrangian Transport (STILT), driven by ECMWF-IFS, and (d) to capture the magnitude and variability of measured CO2 fluxes in the city center of Amsterdam (the Netherlands).We show that CTE-HR fluxes reproduce large-scale flux anomalies reported in previous studies for both biospheric fluxes (drought of 2018) and anthropogenic emissions (COVID-19 pandemic in 2020). After applying transport of emitted CO2, the CTE-HR fluxes have lower median root mean square errors (RMSEs) relative to mole fraction observations than fluxes from a non-informed flux estimate, in which biosphere fluxes are scaled to match the global growth rate of CO2 (poor person's inversion). RMSEs are close to those of the reanalysis with the CTE data assimilation system. This is encouraging given that CTE-HR fluxes did not profit from the weekly assimilation of CO2 observations as in CTE.We furthermore compare CO2 concentration observations at the Dutch Lutjewad coastal tower with high-resolution STILT transport to show that the high-resolution fluxes manifest variability due to different emission sectors in summer and winter. Interestingly, in periods where synoptic-scale transport variability dominates CO2 concentration variations, the CTE-HR fluxes perform similarly to low-resolution fluxes (5–10× coarsened). The remaining 10 % of the simulated CO2 mole fraction differs by >2 ppm between the low-resolution and high-resolution flux representation and is clearly associated with coherent structures ("plumes”) originating from emission hotspots such as power plants. We therefore note that the added resolution of our product will matter most for very specific locations and times when used for atmospheric CO2 modeling. Finally, in a densely populated region like the Amsterdam city center, our modeled fluxes underestimate the magnitude of measured eddy covariance fluxes but capture their substantial diurnal variations in summertime and wintertime well.We conclude that our product is a promising tool for modeling the European carbon budget at a high resolution in near real time. The fluxes are freely available from the ICOS Carbon Portal (CC-BY-4.0) to be used for near-real-time monitoring and modeling, for example, as an a priori flux product in a CO2 data assimilation system. The data are available at 10.18160/20Z1-AYJ2 .
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The retailing industry in the UK is experiencing unprecedented structural change. The impact on retailers has often dominated headlines, along with the impacts on local services and economies, but with little attention given to the implications for property owners and practitioners. Exploring and understanding the responsiveness of landlords, and their behaviours, is essential to understanding the adaptiveness of a retailing system. This study employs semi-structured interviews to examine the short- and long-term changes in the retail market and the actions of landlords in response. The findings span the period prior to and during the first year of the Covid-19 pandemic in 2020, and reveal that fundamental changes have occurred to establish tenant covenant norms and the traditional retail leasing model. The paper explores these changes, including a shift in tenant risk, reposition of the leasing model in favour of tenants, generally, and greater application of turnover rents. The pressing challenge for current valuation practitioners, therefore, is to incorporate these fundamental changes within the market into the pricing of retail assets. Significant progress in this area to date, as explored in the paper, has been limited although greater application of discounted cashflow techniques is set to be encouraged by the RICS.
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Public–private partnership (PPP) policy is essential to alleviating the local government debt burden and improving resource allocation efficiency. This paper empirically examines the impact of fiscal pressure on PPP investment in Chinese prefecture-level cities from 2014 to 2019 using the ordinary least-squares (OLS) module. Moreover, we also investigate how fiscal pressure influences PPP investment and test the influenced mechanism from other perspectives. The results show the following. (1) Fiscal pressure on the government has a significant positive effect on PPP investment at the prefectural level. (2) The marketization process is the mediated effect of the relationship between fiscal pressure and PPP investment. Fiscal pressure will stimulate the regional marketization process, thus promoting PPP investment. (3) Fiscal pressure has a significant positive effect on PPP investment in the middle region, while the effect is not significant in the eastern and western regions. Meanwhile, the effect is not significant in central cities, but there is a significant positive effect in ordinary cities. (4) The effect of fiscal pressure on PPP investment is not significant in the private reward mode of government payment, but there is a significant positive effect in the mode of user payment and feasibly insufficient subsidies. Our studies could also provide practical suggestions for sustainable development of PPP policy and solving the fiscal pressure of the current economic recession under the COVID-19 pandemic.
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The COVID-19 pandemic has drastically changed the relationship between space users in the street, public spaces, and public facilities. Restrictions on physical distance (physical distancing) and activity (social distancing) are in place to prevent the spread of the Coronavirus. Borders on physical distance and access to public spaces do not reduce activity in these spaces. Public spaces must have an adaptive response to the spread of the virus while still implementing inclusive practices for all space users. Spatial adaptation patterns overcome the pandemic crisis in public spaces applied temporarily or permanently in the main areas where community activities are carried out. And now, in the transition of post-pandemic, when the city begins to open the pandemic, we hope people will remain comfortable and safe doing activities in public spaces from the spread of the Coronavirus. The specific purpose of this study is to explore the adaptation of community activities spaces that occurred in the centre of Semarang after the pandemic. This study uses a qualitative method with direct observation and interviews. This method captures the phenomenon of public spaces adaptation after the COVID-19 pandemic. The result is a temporary adaptation and viability pattern of community activity spaces in downtown Semarang in the COVID-19 pandemic transition. Hopefully, the finding can support the knowledge about sustainable public space after the pandemic.
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The Tropospheric Monitoring Instrument (TROPOMI) on the Sentinel-5 Precursor (S5P) satellite is a valuable source of information to monitor the NOx emissions that adversely affect air quality. We conduct a series of experiments using a 4×4 km2 Comprehensive Air Quality Model with Extensions (CAMx) simulation during April–September 2019 in eastern Texas to evaluate the multiple challenges that arise from reconciling the NOx emissions in model simulations with TROPOMI. We find an increase in NO2 (+17 % in urban areas) when transitioning from the TROPOMI NO2 version 1.3 algorithm to the version 2.3.1 algorithm in eastern Texas, with the greatest difference (+25 %) in the city centers and smaller differences (+5 %) in less polluted areas. We find that lightningNOx emissions in the model simulation contribute up to 24 % of the column NO2 in the areas over the Gulf of Mexico and 8% in Texas urban areas. NOx emissions inventories, when using locally resolved inputs, agree with NOx emissions derived from TROPOMI NO2 version 2.3.1 to within 20 % in most circumstances, with a small NOx underestimate in Dallas–Fort Worth (-13 %) and Houston (-20 %). In the vicinity of large power plant plumes (e.g., Martin Lake and Limestone) we find larger disagreements, i.e., the satellite NO2 is consistently smaller by 40 %–60 % than the modeled NO2, which incorporates measured stack emissions. We find that TROPOMI is having difficulty distinguishingNO2 attributed to power plants from the background NO2 concentrations in Texas – an area with atmospheric conditions that cause short NO2 lifetimes. Second, the NOx/NO2 ratio in the model may be underestimated due to the 4 km grid cell size. To understand ozone formation regimes in the area, we combine NO2 column information with formaldehyde (HCHO) column information. We find modest low biases in the model relative to TROPOMI HCHO, with -9 % underestimate in eastern Texas and -21 % in areas of central Texas with lower biogenic volatile organic compound (VOC) emissions. Ozone formation regimes at the time of the early afternoon overpass are NOx limited almost everywhere in the domain, except along the Houston Ship Channel, near the Dallas/Fort Worth International airport, and in the presence of undiluted power plant plumes. There are likely NOx-saturated ozone formation conditions in the early morning hours that TROPOMI cannot observe and would be well-suited for analysis with NO2 and HCHO from the upcoming TEMPO (Tropospheric Emissions: Monitoring Pollution) mission. This study highlights that TROPOMI measurements offer a valuable means to validate emissions inventories and ozone formation regimes, with important limitations.
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Retail is one of the defining elements of urban spaces. The study of commerce is largely based on its evolution and how it relates with urban environments. Currently, with the advent of mass tourism, there has been an adjustment in the commercial fabric of the area’s most sought after by tourists. Among these latter areas, the historical centers of commerce stand out. The first objective of this research is to analyze the modern evolution of the commercial fabric of Lisbon by comparing the city center with the rest of the city. For this goal, I use a quantitative approach through the quotient location for specific retail typologies. The results show dissimilarities that are associated with the geographical location of retail, which vary according to the different retail typologies being analyzed. The second goal is based on the assumption that the mere analysis of the evolution of the retail typologies is limited in the context of tourist cities. Considering this matter, a qualitative method (photo analysis, conceptually supported by the concept of authenticity) is used. The results show the usefulness of the concept of authenticity to apprehend and discuss how retail is reacting to the tourism industry, thereby contributing to the transformation of the city center into a leisure and entertainment destination.
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The changes in human behaviour associated with the spread of COVID-19 infections have changed the urban environment. However, little is known about the extent to which they have changed the urban climate, especially in air temperature (T), anthropogenic heat emission (QF) and electricity consumption (EC). We quantitatively evaluated these effects using a unique method that integrates real-time human population data (social big data) with an urban climate model. The results showed that in an office district in the city centre of Tokyo, the biggest metropolis in the world, under a significantly reduced population, EC (CO2 emissions) would be 30% and QF would be 33% of pre-COVID levels (without the stay-at-home advisories). This resulted in a T decrease of about 0.2 °C, representing about 20% of the past greenhouse gas-induced warming (about 1.0 °C) in Tokyo. This method can be benchmarked and then applied to worldwide. The results suggest that changes in human behaviour can represent an adaptation and decarbonising strategies to climate change in cities.
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Background: The world faces vast health challenges, and urban residents living in high-density areas have even greater demand for healthy lifestyles. Methods: Based on the data of points of interest, a field survey, and an interview, we explored the healthy community-life circle in the downtown area of Chengdu, China from two perspectives: objective measurement and subjective perception of residents. We evaluated the coverage rate and convenience in accessing eight types of health service facilities within a 15-min walk using linear and logistics regression models to explore the degree of resident satisfaction with facilities and influencing factors. Results: Results showed significant differences in coverage rates between different districts. The overall convenience in accessing health service facilities decreased gradually from the city center to the outskirts. The social environment, the layout of health service facilities, and residents’ travel habits were related to health service facility satisfaction. Results also showed significant differences in various facilities’ accessibility satisfaction between objective measurement and residents’ perception measurement. Compared with subjective measurement, the objective measurements of accessibility for sports venues (objectively measured average minus perceived average: −1.310), sports zones (−0.740), and specialized hospitals (−1.081) were lower;those for community hospitals (0.095), clinics (1.025), and pharmacies (0.765) were higher;and facility accessibility measured by subjective perception had a more significant impact on health facility satisfaction. Pharmacies (OR: 1.932) and community hospitals (OR: 1.751) had the largest impact among the eight types of facilities. Conclusion: This study proposed to construct a healthy community-life circle with a category and hierarchy system.
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The problem of the proper functioning of Park-and-Ride facilities seems to be of key importance for ensuring appropriate transport in cities in which the intensity of road traffic is systematically increasing, together with the increase of environmental pollution (air pollution, noise etc.). The attractiveness of a car park of this kind seems obvious – instead of a burdensome journey in one’s own car, one changes the vehicle to fast municipal public transport or another means of transport (a bike, a scooter), or reaches the destination on foot. This results in benefits – above all in terms of comfort (shortening the time of the journey), health advantages etc. As has been proven by experiments, facilities of this kind are an expensive investment, the location of which (e.g. stand-alone) does not always ensure full utilization. The concept presented in the article assumes the possibility of a gradual extension of the multistorey car park following the increase of the demand. The article attempted to demonstrate that one of the sources of increasing attractiveness is the appropriate location (guaranteeing easy commute to the car park), the possibilities to continue the journey in an attractive way, then increasing the attractiveness through the possibility to use various services (shopping, the gym, the swimming pool, cinema, restaurants) and thirdly: the plan of launching the car park and its utilization in the life cycle should ensure the possibility of flexible reacting to changes of the demand (the experiences of the ongoing pandemic indicate that there is no guarantee of ensuring systematic demand increase). An element which also seems significant is the limitation of costs in the initial stage of investments of this kind with the possibility of gradual extension following the change of user habits.
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Covid-19 has brought Chiang Mai International Airport to a state of lethargy: the once tourism-oriented city in northern Thailand has seen its visitors arriving by air greatly reduced since the start of the pandemic. An analysis of airport spaces and usage shows that their core purposes are disrupted or at standstill. Using a qualitative approach, the purpose of this study is to propose a guideline to re-assess spaces of city-centered airports in times of crisis to help its urban regeneration. Urban recommendations are displayed for policymakers and then applied to Chiang Mai International airport context. Results found that temporary urban and architectural solutions are worth considering during the time of crisis and its unknown end date. Permanent solutions are also suggested to connect dynamic poles of the city with the airport area, leading to improve the reliance between Chiang Mai city and its airport. This prospective approach also sheds a light on the monofunctional purpose of the airport and relative seclusion issues due to single-use zoning in the fabrication of the city.
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High developed industry regions, provincial centers with a heavy traffic and dense populations with cold winters, using low-quality fossil fuel consumption have an effect on quality of life especially for people with respiratory diseases. The air quality data gathered from air monitoring stations for the City Center of Konya, Turkey were analysed statistically during the period when curfew due to the Covid-19 pandemic in 2020. The restrictions that cause the reduction of vehicle exhaust emissions, which are important factors in the formation of some air pollutants, are thought to be effective in improving the air quality as well as meteorological conditions are effective on the days when the air quality is analysed. It is thought that the reduction in HC, NOx, CO and PM emissions, which can be evaluated as exhaust emissions, will be an effective factor due to the restrictions of Covid-19 pandemic. Comparing between the 2019 and 2020 MCO data, we identified that most of the gases decreased with NO2 (-24 µg/m3), SO2 (-24 µg/m3), CO (-37 µg/m3) and an increment of O3 of +50 µg/m3 which indicates that the MCO and restricted of movement were give an impact to air quality levels in Konya City. The increase in O3 values were found by the existing of the sun rays in the atmosphere with the formation of O3 during the clean air period.
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The surprisingly heavy social impacts were amplified by a combination of circumstances such as damage concentrated in the dense urban city center, the number of people requiring alternative accommodation and the relatively cold weather. Interdisciplinary research and training in particular in the fields of Earthquake Engineering and Seismic Risk assessment and management is crucial for improving the design of new structures, retrofitting the existing ones and efficiently respond and recover from disastrous earthquakes. The analysis is conducted on a tramway network scale to identify critical locations by performing continuous monitoring on the tramway network and risk analysis based on the distance of buildings from the track, vibration amplitude at source, and building damage. The paper presents a failure analysis of the bell tower of the church of St. Francis of Assisi on Kaptol in Zagreb subjected to seismic activity using the finite-discrete element method—FDEM.