Megacities Population Research Articles

An Optimization Approach considering Passengers’ Space-Time Requirements for Bus Bridging Service under URT Disruption

Rapid urbanization and growth of population in megacities generate severe pressures on urban rail transit (URT) system. The quantity and frequency of disruptive events have increased significantly, which might have obvious adverse impacts. A large number of passengers are stranded at disrupted URT station when a disruptive event occurs. One essential solution for passenger evacuation is the bus bridging service. This paper is aimed at addressing the passenger evacuation problem caused by a disruptive event in the URT network, by proposing a bus bridging service model considering the passengers’ space-time requirements. The model is proposed to minimize the waiting time of passengers and considers factors including bus service capacity limitations, bus stop parking capacity, and the maximum bridging time limit of a single bus. Buses are assumed to provide bridging service on either the local bus route or the direct bus route. The optimal routes and scheduling plans of bridging bus are designed. The model is applied to an example of a disruptive event in Shanghai URT line 9. The results of this example show that the proposed model is capable of reducing the waiting time of passengers and the number of buses used by 3.2% and 24.7%, compared with the traditional bus bridging service. Further analysis of the example shows that it is not a cost-effective solution to reserve a large number of buses for URT disruption. Decision-makers should comprehensively trade off between passengers’ space-time demands and monetary costs of bus bridging service.

Detection of urban trees sensitivity to air pollution using physiological and biochemical leaf traits in Tehran, Iran

The increased population in megacities has recently exacerbated the need to combat air pollution. This study examined the concept that the sensitivity and tolerance of urban plant species to air pollution might be used to determine Tehran, Iran's air quality and obtain suitable urban greening. The air pollution tolerance index (APTI) was derived using the total chlorophyll, relative water content, pH, and ascorbic acid content of leaf extract from Morus alba, Ailanthus altissima, and Salix babylonica trees as an indicator of the sensitivity and tolerance of urban plant species. A. altissima and S. babylonica, with APTI values of 11.15 and 11.08, respectively, were sensitive to air pollution and can be employed as bioindicators, whereas M. alba, with an APTI value of 14.08, exhibited moderate resistance to air pollution and is therefore recommended for urban planting. Furthermore, the content of enzymatic and non-enzymatic parameters (carotenoid, phenol, and flavonoids) and proline concentration in the polluted seasons and sites (3 and 4) have been increased in M. alba. Collectively, we expect our findings to contribute to the rapidly growing body of research aiming to find a suitable urban greening for a wide range of polluted megacities.

Opportunities for Transforming Fundamental Physics Researchinto an Innovative Product

Currently, humanity, our entire civilization needs long–term forecasts of emergencies and systems of individualized control of the actions of people and robots (AI systems) in the event of an emergency in order to radically reduce human and material losses. This was shown by the events of this year – catastrophic in scale fires, floods, earthquakes, apparently associated with global space phenomena, and man–made disasters, including epidemics associated with the pace of economic activity – the concentration of the world's population in megacities, globalization of the economy, population mobility, etc. The article shows that only the introduction of a mass service of individualized subscriber rescue management (IUSA) of an infocommunication network with sensors developed as a result of fundamental physical studies, and its full–fledged industrial operation can be accelerated by creating the Association of Researchers of Applied Physics Problems (ARAPP).

The Effect of the Concentration of the Fish Processing Offal Powder, of the Humidity Level and of the Cross-Sectional Area of the Die Molding Channel on the Technological Parameters of the Extrusion Process and on the Quality Characteristics of Potato Snacks

The investigation is focused on solving the problems of protein deficiency in the diets of the megacities population and on the cost-effective utilization of the offal from processing salmon fishes through the development of energy efficient and environmentally friendly technology for the potato snacks production. The aim of the work is to study the process of obtaining extruded expanded potato-based snacks in a single-screw extruder and to develop through an empirical research a method of industrial production of potato snacks enriched with proteins from the offal of processing salmon fishes. As a result of the study, it was established that the addition of 10% of offal salmon fish powder processing to potato flakes provided a fairly high nutritional value, good organoleptic and physic-chemically parameters in all extrudate samples. We also established the kinetics of extrusion of the fish-potato mixture, more specifically, we found out that the dependences between the initial moisture content in the mixture and the pressure in the extruder chamber, and between the initial humidity and the temperature in the chamber are inversely proportional; the dependence between the expansion ratio and the starch content in the extruded mixture is directly proportional, and the dependence between the expansion ration and the molding channel diameter is inversely proportional. Solutions obtained in the investigation can be used by enterprises engaged in the production of extruded snacks in order to optimize the working conditions of extrusion of potato extrudates and to reduce production costs.

Poverty reduction during the rural–urban transformation: Rural development is still more important than urbanisation

Based on cross-country panel datasets, we find that (i) an increase in population share in agriculture is associated with poverty reduction once the longer-term poverty change or the dynamic is taken into account; (ii) rural non-agricultural sector also is poverty reducing in some cases; and (iii) increased population in the mega cities has no role in poverty reduction. In fact, the growth of population in mega cities is “poverty-increasing” in a few cases. Given that a rapid population growth or rural–urban migration is likely to increase poverty, more emphasis should be placed on policies that enhance support for rural agricultural and non-agricultural sectors. If our analysis has any validity, doubts are raised about recent research emphasising the role of secondary towns or urbanisation as the main driver of extreme poverty reduction.

Social Construction Based on Long-Distance Water Diversion Projects — A Case Study on the Yuqiao Reservoir in Tianjin

The exploding population in megacities and large cities has led to increasingly tight water supply, and large-scale cross-regional water diversion projects have arisen accordingly. A long-distance water diversion project creates environmental, economic, and social connections between the water source and receiving areas. In this paper, the Yuqiao Reservoir in Tianjin is taken as an example. Its severe situation of environmental pollution is introduced, and an analysis is conducted that the weaknesses of its current management measures are public service and social relations construction. This paper proposes the key concept of water relationship, defining it as a new-type, peer-to-peer, inter-area connection, and suggests that the construction should be steered in the four dimensions of social infrastructure, balanced mechanism design, environmental information communication, and mutual-aid environmental actions. This paper advocates that an environmental protection concept should be specifically directed, an action plan that gives balanced and reasonable consideration to public and private interests should be available for environmental actions, and environmental undertaking should be carried out on the basis of internal needs of participants.

Mapping spatial variation of population aging in China's mega cities

Based on the statistics of the fifth and sixth censuses in China, this paper, which focuses on the spatial distribution characteristics of aging population in China's mega cities, examines the distribution of aging in Beijing, Shanghai, Guangzhou, and Wuhan. In this paper, an Aging Degree Index and an Aging Population Mean Center have been used to analyze the spatial distribution characteristics and spatial variation trends of aging population in mega cities. According to the research, the spatial distribution of aging population shows a faster development tendency of suburbanization from two different perspectives: one tendency is centrifugal spread associated with seniors who are moving from the city center to outer suburb areas, and the other is center concentration where the seniors who lived in the outer suburb areas are moving towards the city center.

Analysis of Modern Cities’ Prosperity by Focusing on the Relationship between Small Demographic Centers and Metropolitan Centers and Improving Living and Service Standards in Metropolitan Areas

Abstract. The unbridled and quick growth, the excessive density and concentration of population in mega cities have made these cities unable to continue a healthy urban life and in fact they are unable to provide their residents with necessary services. With the aim of reaching the economic and social balanced growth and controlling its unbridled growth and regarding the mentioned problems in the metropolitan areas, creation of new cities around big cities with a reasonable distance in order to decrease population and its attractions was suggested. The new city of Pardis about 35 km northwestern Tehran across the Ab-Anjirak lands has been developed in order to organize the settlement system, to absorb the population overflow of Tehran and alleviating Tehran challenges. This study tries to analyze whether Pardis City is successful, its performance to absorb the population overflow of Tehran City, the significant reasons for moving into this city and analyzing the former settlements of households living in this city now. Some demographic indicators were used for indicating the prosperity of Pardis City; a questionnaire was designed in order to analyze the reasons that encourage people to move in to this city. The results show that this city has failed to absorb the predicted population and inexpensive lands and housings are among the main reasons for why people tend to move to this city; however, analysis of the former settlements of its residents indicate that most people who have moved to Pardis were used to live in Tehran City already.