Urban Areas In Asia Research Articles

Air quality challenges in Central Asian urban areas: a PM2.5 source apportionment analysis in Dushanbe, Tajikistan.

This work presents the first comprehensive assessment of PM pollution sources in Dushanbe, Tajikistan. A total of 138 PM2.5 samples were collected during 2015-2016 and 2018-2019 and were analyzed through gravimetric, ED-XRF, and multi-wavelength absorption techniques. The results show that PM2.5 concentrations were substantially higher than the European annual limit value and WHO Air Quality Guidelines annual average value, with an average of 90.9 ± 68.5μgm-3. The PMF application identified eight sources of pollution that influenced PM2.5 concentration levels in the area. Coal burning (21.3%) and biomass burning (22.3%) were the dominant sources during the winter, while vehicular traffic (7.7%) contributed more during the warm season. Power plant emissions (17.5%) showed enhanced contributions during the warm months, likely due to high energy demand. Cement industry emissions (6.9%) exhibited significant contribution during the cold period of 2018-2019, while soil dust (11.3%) and secondary sulphates (11.5%) displayed increased contribution during the warm and cold months, respectively. Finally, waste burning (1.5%) displayed the lowest contribution, with no significant temporal variation. Our results highlight the significant impact of anthropogenic activities, and especially the use of coal burning for energy production (both in power plants and for residential heating), and the significant contribution of biomass burning during both warm and cold seasons.

Different mode, different travel? Insights into the travel behavior of e-scooter sharing using credit card big data and a mobile survey in Seoul

Previous studies regarding e-scooter sharing mainly focused on analyzing the risk factors and the socioeconomic characteristics of users. Moreover, these studies had limitations, such as the small amount of data for policy implications and the restricted geographic scope centered on western countries with minimal attention on Asian urban areas. To overcome such limitations, this research has aimed to identify clearer features of behavioral aspects of e-scooter sharing by utilizing credit card big data and conducting a mobile survey amongst users in Seoul including various time slots during the COVID-19 outbreak. The findings revealed two peak times for e-scooter sharing during the week with heightened activity on weekends and holidays. It was noted that e-scooter sharing substituted other modes of transportation from midnight to 05:00. The majority of users were men and young people, driven primarily by the motivation for leisure and fun. High levels of patronage and customer satisfaction were identified, but there was a need for fundamental facilities to support sustained usage. Although the COVID-19 pandemic had an impact on e-scooter sharing usage, quantifying its extent has proven to be challenging. Weather conditions also influenced usage patterns, which varied across different regions. E-scooter sharing was used both as a complement and substitute for traditional transportation modes depending on specific situations. It was concluded that e-scooter sharing was not viewed as a replacement for cars, but often used to connect with mass transit. Consequently, the sustainability of its services remains a subject of debate.

Modeling atmospheric microplastic cycle by GEOS-Chem: An optimized estimation by a global dataset suggests likely 50 times lower ocean emissions

Modeling atmospheric microplastic cycle by GEOS-Chem: An optimized estimation by a global dataset suggests likely 50 times lower ocean emissions

Respiratory Disorders Related to e-Waste Exposure among Workers in the Informal Sector in a Sub-Saharan African City: An Exposed Nonexposed Study.

Introduction Exposure to electrical and electronic equipment waste (e-waste) has become a growing health concern. The objective of this study was to measure the effect of exposure to e-waste on respiratory symptoms and on lung function parameters in workers involved in informal recycling activities in Cotonou city, Benin. Methods This was a cross-sectional study, in which exposed e-waste workers in Cotonou city were randomly selected. A matching nonexposed group based on age and sex was recruited from the general population. Respiratory symptoms were investigated using a questionnaire adapted from the British Medical Research Council's standardized respiratory questionnaire. Participants underwent lung function test using a portable spirometer (MIR SPIROBANK). Data were analyzed with STATA version 15 software. Results The overall prevalence of respiratory symptoms in e-waste workers was statistically higher in the exposed group (33.1% vs. 21.6%; p = 0.027). Chest tightness (11.8% vs. 2.1%; p = 0.003) and breathlessness (6.8% vs. 1.4%; p = 0.018) were the most reported symptoms by e-waste workers. Lung function testing showed a higher proportion of disorders among e-waste workers (25.0% vs. 14.9%, p = 0.029), with a higher proportion of probable restrictive (10.8% vs. 2.7, p = 0.005) and mixed (4.1% vs. 0%, p = 0.013) ventilatory disorders. Handling or working with e-waste was found associated with a significant reduction in forced expiratory volume in one second (FEV1) by 0.4 L (95% CI: 0.3-0.6) and forced vital capacity (FVC) by 0.75 L (95% CI: 0.6-0.9) after adjustment for age, BMI, smoking habits, asthma history, and daily income. Conclusion Work involving e-waste is associated with a higher prevalence of respiratory symptoms and with an increased risk of FEV1 and FVC decline, as well as of lung function impairment, particularly of restrictive disorders. Further studies to better clarify this association are needed. Awareness on this major public health threat should be raised in other sub-Saharan and Asian urban areas.

Greenhouse gas emissions from global cities under SSP/RCP scenarios, 1990 to 2100

Projections of greenhouse gas (GHG) emissions are critical to enable a better understanding and anticipation of future climate change under different socio-economic conditions and mitigation strategies. The climate projections and scenarios assessed by the Intergovernmental Panel on Climate Change, following the Shared Socioeconomic Pathway (SSP)-Representative Concentration Pathway (RCP) framework, have provided a rich understanding of the constraints and opportunities for policy action. However, the current emissions scenarios lack an explicit treatment of urban emissions within the global context. Given the pace and scale of urbanization, with global urban populations expected to increase from about 4.4 billion today to about 7 billion by 2050, there is an urgent need to fill this knowledge gap. Here, we estimate the share of global GHG emissions driven by urban areas from 1990 to 2100 based on the SSP-RCP framework. The urban consumption-based GHG emissions are presented in five regional aggregates and based on a combination of the urban population share, 2015 urban per capita CO2eq carbon footprint, SSP-based national CO2eq emissions, and recent analysis of urban per capita CO2eq trends. We find that urban areas account for the majority of global GHG emissions in 2015 (61.8%). Moreover, the urban share of global GHG emissions progressively increases into the future, exceeding 80% in some scenarios by the end of the century. The combined urban areas in Asia and Developing Pacific, and Developed Countries account for 65.0% to 73.3% of cumulative urban consumption-based emissions between 2020 and 2100 across the scenarios. Given these dominant roles, we describe the implications for potential urban mitigation in each of the scenario narratives in order to meet the goal of climate neutrality within this century.

Cloud detection in East Asian urban areas in VIIRS day/night band by texture analysis

Cloud detection in East Asian urban areas in VIIRS day/night band by texture analysis

The Characteristics of Migrant Entrepreneurs in South Jakarta

The migrant entrepreneur plays a crucial role in economic development of the city. However, scant attention has been given to the study of the characteristics of migrant entrepreneurs in the context of urban areas in Asia, especially in Indonesia. Therefore, this paper identifies the main characteristics of migrant entrepreneurs in South Jakarta. The research itself involves sixty-eight first-generation migrant entrepreneurs as respondents of the survey. The characteristics of migrant entrepreneurs are analysed using descriptive statistics method of frequency distribution analysis. The analysis has been conducted based on background characteristics, cultural characteristics, business-related goals, business strategy, and performance. The analysis has revealed that the existence of migrant entrepreneurs in Jakarta has a positive impact not only on the development of the city but also on the development of their own homeland.

Non-linear backstepping speed control for Asian electric scooter uses

The electric scooter has become very popular especially in large European and Asian urban areas, thanks to its some advantages. While its popularity is increasing, studies about these electric scooters are also increasing. The main objective of this study is to introduce the design of an autonomy extended electric three-wheeled scooter. For this aim, a model is obtained firstly and it is driven by two BLDC motors placed on the rear wheels independently controlled by a non-linear controller named as Backstepping. Indeed, it contains a powerful electronic differential system to ensure the security of passenger while entering the curved road. The studied model is simulated through the MATLAB Simulink environment where interesting results are shown in results.

Simulation and design of a kit for the electrification of a light tricycle truck

Light tricycle trucks represent a diffused kind of vehicle in urban areas in Asia, Africa and South America. Tricycle offers a cheap and agile solution for transportation of goods in crowded urban areas. Despite to its diffusion, electrification of this kind of vehicle has been neglected by large industrial groups since it involves low margin of profit with respect to upgraded vehicles. However, electrification of tricycles should be important for a world sustainable growth. A simple and cheap electrification kit is proposed in this study. Proposed solution can be used to upgrade existing vehicles with limited investments. An APE Piaggio, a widely diffused vehicle is considered as benchmark test case. Vehicle dynamics is modelled in order to optimise various aspects related to installation, and weight distribution. Particular attention is paid to optimisation of regenerative braking and its blending with mechanical one to maximise autonomy and to preserve vehicle stability.

Simulation and design of a kit for the electrification of a light tricycle truck

Light tricycle trucks represent a diffused kind of vehicle in urban areas in Asia, Africa and South America. Tricycle offers a cheap and agile solution for transportation of goods in crowded urban areas. Despite to its diffusion, electrification of this kind of vehicle has been neglected by large industrial groups since it involves low margin of profit with respect to upgraded vehicles. However, electrification of tricycles should be important for a world sustainable growth. A simple and cheap electrification kit is proposed in this study. Proposed solution can be used to upgrade existing vehicles with limited investments. An APE Piaggio, a widely diffused vehicle is considered as benchmark test case. Vehicle dynamics is modelled in order to optimise various aspects related to installation, and weight distribution. Particular attention is paid to optimisation of regenerative braking and its blending with mechanical one to maximise autonomy and to preserve vehicle stability.

Anisotropic corrections for the downwelling radiative heat transfer flux from various types of aerosols

Comprehensive Monte Carlo simulations are used to correct deviations in the atmospheric downwelling longwave (DLW) radiative flux calculated by isotropic scattering assumptions. The widely used δ-M approximation is validated for low to medium values of aerosol loading. For very high aerosol loading conditions, the δ-M approximation incurs an error. Here we propose scaling corrections for extreme loading conditions routinely found in selected urban areas in Asia, but also in other continental and coastal areas susceptible to large-scale wildfire pollution (Western USA) or dust storms (Mediterranean regions and Northern Africa). The scaling rules are expressed as functions of the normalized aerosol optical depth t∗ and the scattering asymmetry factor eg. An exponential relationship between the DLW deviation that assumes isotropic scattering and t∗ is found, and the corresponding fitting coefficients are correlated for different types of aerosols (sample internal mixing, urban, continental and marine aerosols). The δ-M approximation is sufficiently accurate when aerosol optical depths (AOD) at the ground level are smaller than 0.5. For AOD beyond this threshold, the proposed scaling rule corrections should be used for estimation of downwelling thermal radiative fluxes. The effects of moisture content on aerosol composition and on DLW radiative fluxes are also investigated for all conditions of interest.

The Role of Iberian Institutions in the Evolution of Macao

Since around 1555, the Portuguese had as of now gotten comfortable Macao. Albeit encompassed by Chinese urban areas, Macao oversaw for quite some time to save and foster the Portuguese attributes that are clear in the city design. This western trademark is the thing that these days makes Macao not the same as its neighbors and is the foundation of the city’s special “Social Identity” (CI). The city CI is such a significant element that the People’s Republic of China proposed to UNESCO that they remember Macao for the World Heritage list. Taking into account that over 95% of the populace is of Chinese beginning, we currently bring up a significant issue: what was the course of Macao’s establishment and how could it be to keep up with the Portuguese qualities for such a long time in the midst of an ocean of Asian development and culture? The response is significant, in understanding the city’s set of experiences, yet additionally to make it conceivable to safeguard the Macao CI for people in the future. Following a near strategy for examination of the similitudes and contrasts with other abroad Portuguese urban areas in Asia, and in the wake of investigating the chronicled development of Macao, we recognized the critical components and hints that could give the response to this significant inquiry. The finishes of the examination highlight the recognizable proof of the Portuguese standards for settling, and the Iberian foundations’ liability in keeping up with the Portuguese qualities that mirror the city’s social association. The western social personality of the city was produced by its Iberian foundations through a viable equal improvement with the Chinese towns which involve a similar landmass.

Trait-dependent tolerance of bats to urbanization: a global meta-analysis.

Urbanization is a severe threat to global biodiversity, often leading to taxonomic and functional homogenization. However, current urban ecology research has focused mostly on urban birds and plants, limiting our ability to make generalizations about the drivers of urban biodiversity globally. To address this gap, we conducted a global meta-analysis of 87 studies, including 180 bat species (Chiroptera) from urban areas in Asia, Australia, Europe, North and South America. We aimed to (i) understand the importance of functional traits and phylogeny in driving changes in urban bat assemblages, and (ii) assess the capacity of traits for predicting which types of species are most sensitive to urbanization. Our results indicate that species-specific functional traits explain differences in the intensity of urban habitat use. Urban tolerance mainly occurred within the open and edge space foraging and trawling species as well as in bats with flexible roosting strategies. In addition, across bioregions and independent of phylogeny, urban tolerance correlated with higher aspect ratio, a trait enabling fast flight but less agile manoeuvres during aerial food acquisition. Predictive success varied between bioregions, between 43 and 83%. Our analysis demonstrates that the local extinction of bat species in urban areas is non-random, trait-based and predictable, allowing urban landscape managers to tailor local conservation actions to particular types of species.

Characterizations of atmospheric particulate-bound mercury in the Kathmandu Valley of Nepal, South Asia.

The Kathmandu Valley, located in the Himalayan foothills in Nepal, is heavily polluted. In order to investigate ambient particulate-bound mercury (Hg) in the Kathmandu Valley, a total 64 total suspended particulates (TSP) samples were collected from a sub-urban site in the Kathmandu Valley, the capital region of Nepal during a sampling period of an entire year (April 2013-April 2014). They were analyzed for ambient particulate-bound Hg (PBM) using thermal desorption combined with cold vapor atomic spectroscopy. In our knowledge, it is the first study of ambient PMB in the Kathmandu Valley and the surrounding broader Himalayan foothill region. The average concentration of PBM over the entire sampling period of a year was found to be 850.5 (±962.8) pg m-3 in the Kathmandu Valley. This is comparable to those values reported in the polluted cities of China and significantly higher than those observed in most of urban areas in Asia and other regions of world. The daily average Hg contents in TSP (PBM/TSP) ranges from 269.7 to 7613.0ngg-1 with an average of 2586.0 (±2072.1) ng g-1, indicating the high enrichment of Hg in TSP. The average concentrations of PBM were higher in the winter and pre-monsoon season than in the monsoon and post-monsoon season. The temporal variations in the strength of anthropogenic emission sources combined with other influencing factors, such as ambient temperature and the removal of atmospheric aerosols by wet scavenging are attributable to the seasonal variations of PBM. The considerably high dry deposition flux of PBM estimated by using a theoretical model was 135μgm-2yr-1 at the Kathmandu Valley. This calls for an immediate attention to addressing ambient particulate Hg in the Kathmandu Valley, including considering it as a key component of future air quality monitoring activities and mitigation measures.

Emerging solutions to the water challenges of an urbanizing world.

The top priorities for urban water sustainability include the provision of safe drinking water, wastewater handling for public health, and protection against flooding. However, rapidly aging infrastructure, population growth, and increasing urbanization call into question current urban water management strategies, especially in the fast-growing urban areas in Asia and Africa. We review innovative approaches in urban water management with the potential to provide locally adapted, resource-efficient alternative solutions. Promising examples include new concepts for stormwater drainage, increased water productivity, distributed or on-site treatment of wastewater, source separation of human waste, and institutional and organizational reforms. We conclude that there is an urgent need for major transdisciplinary efforts in research, policy, and practice to develop alternatives with implications for cities and aquatic ecosystems alike.

Integrating long-term seismic risk changes into improving emergency response and land-use planning: a case study for the Hsinchu City, Taiwan

An increasing number of rapidly growing urban areas in Asia are becoming more vulnerable to seismic hazards in their development process. However, local authorities rarely integrate seismic risk into the procedure of emergency and land-use planning. This article explores the question of whether seismic risks for urban areas are increasing or diminishing over time, while trends such as population growth and land development in hazard-prone areas increase the potential for loss in disasters. The net effects of such urbanization factors are examined through the use of simulation models that estimate building inventory and seismic loss changes. Seismic losses are modeled for a comparative analysis under the same hypothetical earthquake events hitting at different points in a city area’s long-term development. A case study of seismic risk assessments is illustrated by the Hsinchu City, Taiwan. Results of a prospective analysis indicate that, for the same seismic events, overall risk is expected to increase due to a forecast 2.9 % growth in building inventory. This increment in loss is largely attributed to a large amount of initial buildings predicted to be developed into commercial and industrial uses. However, the spatial pattern of risk would change slightly; particularly, the southeastern, eastern, and some older core areas would be the most vulnerable and risky both at current and future time periods. The approach here enables city planners to incorporate seismic risk analysis into predisaster emergency and land-use planning to encourage risk-reduction strategies.

The geography of urban greenhouse gas emissions in Asia: A regional analysis

This paper aims to advance two objectives: (1) identify and explore greenhouse gas emissions from urban areas in Asia at the regional level; and (2) explore covariates of urban greenhouse gas emissions. We use the Emissions Database for Global Atmospheric Research estimates for carbon dioxide, methane, nitrous oxide, and sulfur hexafluoride from 14 source activities for the year 2000, which are allocated on a 1/10° global grid. We extract emissions for 3535 urban extents all with populations over 50,000, accounting for approximately 91% of the region's urban population. We use regression analysis to associate emissions with urban area and growth, economic, and biophysical characteristics. Our findings suggest that urban areas account for between 30 and 38% of total anthropogenic greenhouse gas emissions for the region and that emission per capita averages from urban areas are lower than those at the national level. Important covariates for total urban greenhouse gas emissions include population size, density and growth rate, income per capita, development status and elevation. This is a first and preliminary assessment of regional baseline trends using these data and this top-down analysis.

Burden of Dyspepsia in Rural and Urban Asia: Author's Reply.

TO THE EDITOR: We sincerely appreciate the interest and comments of Dr. Lu1 on our recently published paper in this journal.2 Dr. Lu points out that the differences in economic impact of dyspepsia between rural and urban communities were not entirely surprising, due to differences in socioeconomic status and healthcare facilities between both populations. Whilst we agree with this statement, it is important to highlight that no such observation has been published in the English literature to date. In the light that dyspepsia is a condition that affects communities in both rural and urban areas in Asia, our findings are highly relevant. This difference in economic impact additionally provides useful information for health economists and providers, particularly in developing strategies on where to focus healthcare services. It is true that studying the economic impact between subjects with and without dyspepsia, regardless of type of community, would have provided further information on the economic impact of dyspepsia. However, the questionnaire that we had developed for the population-based study was not designed to obtain this data. Nevertheless, we hope that this important aspect can be examined in future studies in this area. We also concur with Dr. Lu's second statement that histamine 2 blocker or proton pump inhibitor therapy have both been shown to be superior to simple antacids in the initial management of uninvestigated dyspepsia.3 We believe there are at least 2 possibilities for the excessive use of antacids as opposed to anti-secretory therapy in our population. Firstly, a significant number of adults with dyspepsia were self-medicating, and antacids are more available in both pharmacies and retail outlets in this country compared to anti-secretory medication. Whilst the cost of some generic histamine 2 blockers are relatively low, the ret outlet price of antacids remains the cheapest for the average consumer in this country. Secondly, most patients consulted primary care physicians and not secondary care specialists. It is possible that the primary care physicians in this country are less familiar with evidence-based management of dyspepsia compared to Gastroenterologists or Internal Physicians, resulting in a greater use of antacids compared to anti-secretory therapy. Although the latter is only an assumption, it is likely that more local or regional guidelines, such as the recently published Asian Consensus on Functional Dyspepsia,4 will prove useful in disseminating evidence for clinicians locally.

Potenziale flexibler integrierter semizentraler Infrastruktursysteme in der Siedlungswasserwirtschaft

Dynamics like climate or demographic changes require a new flexibility, which existing infrastructure systems in Germany cannot perform. The general assumption centralized systems within urban areas of middle or high density offer advantages compared to decentralized structures has to be scrutinized under changing conditions. The following paper introduces an innovative approach of integrated, sector crossing infrastructure systems developed for fast growing urban areas in Asia and screens for transfer potentials of this approach, in order to develop strategies to cope with arising problems in infrastructure matters in Germany. The paper closes with strategic recommendations for changing infrastructure development and offers strategies for adapting current infrastructure elements in order to perform better under changing conditions.

Erratum to “Integrated research on subsurface environments in Asian urban areas” [Science of the Total Environment 404 (2008) 377-396

Erratum to “Integrated research on subsurface environments in Asian urban areas” [Science of the Total Environment 404 (2008) 377-396