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Economic analysis of transit facility preservation
Published in Zongzhi Li, Transportation Asset Management, 2018
Specifically, the study cost includes costs for feasibility study, preliminary study, and project study. This cost is related to the transit route length. The cost for land and rights is related to the characteristics of the location, such as population density. Infrastructure building cost includes preparation of the ground, embankments, drainage, structures, fences, noise-protection equipment, and so on. It is always expressed in per unit length cost. Rail transit track cost includes ballast, sleepers or crossters, rail fastening, rails, welds or fish-platings, laying, and initial additional maintenance. Traction equipment cost includes cost of substations and the cost of catenary. The signaling cost includes cables, automatic block system, spot repetition of signal, cab signal, communication channel between the control center and the train, and the level crossing with light and acoustic signals and automatic barriers.
Contextualizing the Sanitation Problem
Published in Pedi Chiemena Obani, Strengthening the Human Right to Sanitation as an Instrument for Inclusive Development, 2018
First, insecurity and conflicts (such as intra-communal dissensions over sanitation projects or conflicts over transboundary water resources) may hamper access to sanitation services through the destruction of sanitation infrastructure (Obani & Gupta, 2015), and limited social cohesion (often lacking in informal settlements or among people living in humanitarian situations or populations in transit) to support self-help enterprises (Isunju, 2011). Second, lack of education and awareness, minimal engagement with the relevant agencies and failure to report service problems also hinder sanitation and hygiene awareness, sustainability of services, and enforcement of civic rights (Munamati et al., 2016; Akpabio, 2012). Third, mass migration and rapid urbanisation creates additional stress for existing resources and increases the likelihood of the spread of water and sanitation related diseases in the absence of adequate infrastructure (Vuorinen, 2007). Fourth, in formal and informal settlements and emergencies, population density significantly increases pollution (Saqib et al., 2016), and affects the sustainability of sanitation infrastructure like sewer systems (Cairns-Smith et al., 2014; Schouten & Mathenge, 2010).
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Published in Zahrah Naankwat Musa, Satellite-Based Mitigation and Adaptation Scenarios for Sea Level Rise in the Lower Niger Delta, 2018
In figure 5.5 the eastern end of the Niger delta (from Bonny to the southern end of Opobo (made up of six coastal segments: 49-54) is the longest stretch with very high vulnerability to SLR. As shown in the case of segment 52, such areas with ‘high’ to ‘very high’ vulnerability are characterized by ‘very low’ to ‘low’ slopes, ‘very low’ to ‘low’ topography, ‘high’ to ‘very high’ mean wave heights, unconfined aquifers, presence of coastal infrastructure and ‘high’ population density, etc. These variables represent physical coastal properties, human influence, and social properties. The presence of human influence variables such as coastal infrastructure and high population density, increase the probability of damage to lives and property when a disaster occurs. The combination of these properties has made the coastal segments highly vulnerable to SLR. The coastal segments classified as highly vulnerable to SLR will require mitigation measures to be applied against SLR.
A spatial evaluation method for earthquake disaster using optimized BP neural network model
Published in Geomatics, Natural Hazards and Risk, 2023
Hanxu Zhou, Ailan Che, Xianghua Shuai, Yi Zhang
Population density is a key factor of the risk assessment of natural disasters. It is calculated as the ratio of the population to bare land area. Some strong earthquakes occur in mountainous areas with low population density, thus posing a relatively small threat to people’s lives and property (Ara 2014). Owing to the strong mobility of the population, it is difficult to obtain the spatial distribution of the population at the moment before the earthquake occurs. Therefore, the resident population of each county in the census was used to approximate the population distribution (Figure 2(c)). Population density is the ratio of the population to the area of each county. It can be noticed from Figure 2(c) that the distribution of population density in geographical space had the characteristics of less in the west and more in the east. People were mainly concentrated in the basin of low elevation. The population data were updated in 2011 and provided by the China Earthquake Network Center.
Evaluation of ecological security and ecological maintenance based on pressure-state-response (PSR) model, case study: Fuzhou city, China
Published in Human and Ecological Risk Assessment: An International Journal, 2022
Shuhui Lai, Jinming Sha, Ahmed Eladawy, Xiaomei Li, Jinliang Wang, Eldar Kurbanov, Zejing Lin, Longbin Wu, Run Han, Yung-Chih Su
Population density refers to the number of people living per unit area of land, which can reflect the density of population living in various regions of the world. According to previous research results (Yuanwei 2020), population distribution is closely related to construction land distribution. Query Fuzhou statistical yearbook, this article will assign of each area county, the population to the grid, then will the land use data of construction land classification, created 300 m300 m grid, each grid construction land area is calculated using the area TAB proportion, finally will be used in front of the three grids calculator multiply by the final population density.
Assessment of ecological vulnerability of resource-based cities based on entropy-set pair analysis
Published in Environmental Technology, 2021
Gang He, Keyu Bao, Wenwen Wang, Yanna Zhu, Shuzhou Li, Lan Jin
In the system of society, the indexes ‘population density’ and ‘resource dependence’ have the highest weights. Population density represents the population distribution in an area. High population density will put great pressure on the ecological environment. Resource dependence is the ratio of fixed assets investment in mining industry to social fixed assets investment. Huainan is a typical resource-based city who has rich coal resources so the development of this city is highly dependent on these resources. But the coal industry would result in many problems such as air and water pollution, vegetation destruction, surface subsidence and so on. These problems will affect regional ecological environment greatly.