scholarly journals Decomposition of 2D polygons and its effect in hydrological models

2018 ◽  
Vol 21 (1) ◽  
pp. 104-122 ◽  
Author(s):  
P. Sanzana ◽  
J. Gironás ◽  
I. Braud ◽  
N. Hitschfeld ◽  
F. Branger ◽  
...  
Keyword(s):  
Urban Areas ◽  
Geographical Information Systems ◽  
Divide And Conquer ◽  
Geographical Information ◽  
Hydrologic Connectivity ◽  
Distributed Modeling ◽  
Distributed Processes ◽  
Spatially Distributed ◽  
Convexity Index ◽  
The Impact

Abstract 2D non-uniform polygonal meshes allow representation of the impact of landscape elements and small infrastructures on water flows. The initial vectorial mesh, derived from the intersection of several geographical information systems' layers, can have highly non-convex or sliver polygons. These bad-shaped elements compromise accurate numerical flow computation. We propose a flexible divide-and-conquer strategy to decompose polygons into physiographical meaningful parts using shape descriptors to better represent the surface terrain and hydrologic connectivity. We use the convexity index (CI) and the form factor (FF) to consider convex and square like optimum shapes. The strategy was applied to two peri-urban areas whose hydrologic response was simulated using distributed modeling. Good-quality meshes were generated with threshold values of CI≈0.8 and FF≈0.2, and CI≈0.95 and FF≈0.4 for undeveloped and highly urbanized zones, respectively. We concluded that the mesh segmentation facilitates the representation of the spatially distributed processes controlling not only the lumped response of the catchment, but also the spatial variability of water quantity and fluxes within it at medium and small scales.

scholarly journals Measuring COVID-19 Vaccination Coverage to Support Healthcare Equity Decision-Making in Urban Areas

2021 ◽  
Author(s):  
Alireza Mohammadi ◽  
Abolfazl Mollalo ◽  
Robert Bergquist ◽  
Behzad Kiani
Keyword(s):  
Vaccination Coverage ◽  
Urban Areas ◽  
Geographical Information Systems ◽  
Public Hospitals ◽  
Geographical Information ◽  
Public Healthcare ◽  
Special Importance ◽  
Decision Matrix ◽  
Spatial Access ◽  
Public Health Decision

Abstract Background: Limited studies have been conducted on access to COVID-19 vaccines and identifying the most appropriate health centres for performing vaccination in metropolitan areas. This study aimed to measure potential spatial access to COVID-19 vaccination centres in Mashhad, the second-most populous city in Iran.Methods: The age structure of the urban census tracts was integrated into the enhanced two-step floating catchment area model to improve accuracy. The model was developed based on three different scenarios: only public hospitals, only public healthcare centres, and the top 20% healthcare centres were employed as potential vaccination facilities. The weighted decision-matrix and analytic hierarchy process based on four criteria (i.e. service area, accessibility index, capacity of vaccination centres, and distance to main roads) were used to choose potential vaccination centres with the highest suitability for residents.Results: Our findings indicate that including the both public hospitals and public healthcare centres can provide high accessibility to vaccination in central parts of the urban areas. However, using only public healthcare centres for vaccination can provide higher accessibility to vaccination sites in the eastern and north-eastern parts of the study area. Therefore, a combination of public hospitals and public healthcare centres is recommended for efficient vaccination coverage.Conclusions: Measuring spatial access to COVID-19 vaccination centres can provide valuable insights for urban public health decision-makers. Our model, coupled with geographical information systems (GIS), provides more efficient vaccination coverage by identifying the most suitable healthcare centres, which is of special importance when only few centres are available.

Geographical Analysis of Entertainment Services in the City of Daratu Using Geographical Information Systems (GIS)

2021 ◽  
Vol 8 (3) ◽  
pp. 618-644
Author(s):  
Hoshmand Jawhar Abbas ◽  
Sanger Ahmed Hussein ◽  
Fatimah Qader Mustafa
Keyword(s):  
Geographical Information Systems ◽  
Urban Expansion ◽  
Well Being ◽  
Geographical Information ◽  
Population Increase ◽  
Recreational Facilities ◽  
Financial Gain ◽  
Recreational Services ◽  
The Impact ◽  
The City

 The impact of the recreational services that exist within the group of services that are practiced within the geographical framework of the city, is not limited to the lives of its residents and their activities, but also on the residents of the surrounding areas. Recreational services contribute to providing diversified investment opportunities for leisure time, so that they are appropriate and beneficial to the health, comfort and well-being of the population at the lowest possible cost, without the goal of their establishment being financial gain, as they lead to the creation of mental, psychological and physical balance on the level of one individual and on the basis of society in a way. In general, recreational services are an integral part of urban activities in most cities of the world. Rather, the concept of modernity and urbanization in contemporary urban centers is measured to some extent by the availability of recreational facilities for their inhabitants, and the study also showed the low level of efficiency of recreational services in terms of their spatial distribution and numbers. As it is concentrated in some neighborhoods of the city, while it is less or absent in other neighborhoods, as well as not taking into account the planning standards in its distribution and during its construction in line with the population increase, urban expansion and the residents' needs for these services. The success in providing these different types of recreational facilities depends on how they are distributed geographically. The balanced distribution of these activities determines the success of the adopted plans in achieving the required goals and policies.

Visualization of Urban Prediction Using Augmented Maps

2012 ◽  
Author(s):  
Sandy Martedi ◽  
Sébastien Callier ◽  
Hideo Saito ◽  
Pega Sanoamuang ◽  
Milica Muminović
Keyword(s):  
Geographical Information Systems ◽  
Green Space ◽  
Geographical Information ◽  
Train Station ◽  
Monitor Display ◽  
Before And After ◽  
Web Camera ◽  
On Line ◽  
The Difference ◽  
The Impact

In this paper, we explore a visualization method using augmented maps for urban prediction. Our implementation allows users to determine the location for prediction in a paper map. As an application example, we examine an area before and after new train station is built. We use the difference between two maps for simulating the changes or predicting the impact if a new train station is built on a location in a paper map. In off-line phase, we gather knowledge data from several reference locations by comparing two aerial maps (before and after the train station is built). We then analyze the difference of green spaces between those two maps using color extraction. We observe that the green space around the new train station mostly decreases due to the area development. This information is then stored for prediction reference. In on-line phase, we use a monocular setup that consists of one camera and a monitor display. A paper map is captured using a web camera and tracked using its geometrical features. These features can be provided using the available data from Geographical Information Systems (GIS) or automatically extracted from the texture. The map is then matched with the reference map in database. When the map is matched, we can overlay the simulation on how the green space will change due to the existence of new train stations on a new location inputted by the user.

Ambient air pollution and health

2016 ◽  
Author(s):  
John Reid ◽  
Giovanni Leonardi ◽  
Alex G. Stewart
Keyword(s):  
Air Pollution ◽  
Geographical Information Systems ◽  
Ambient Air ◽  
Geographical Information ◽  
Ambient Air Pollution ◽  
Background Information ◽  
Traffic Density ◽  
Pollution Indices ◽  
Guideline Values ◽  
The Impact

This chapter describes the impact of air pollution, including particulate matter and nitrogen oxides, on human health, through a case scenario where an increase in respiratory disease has been associated with changes in traffic density and increases in pollution indices. Background information on pollutants and air quality measurements is given based on WHO criteria. The importance of multidisciplinary input to such investigations is emphasized, involving specialists in toxicology and environmental science, as well as health protection staff. The role of geographical information systems in mapping air pollution levels to identify localities where guideline values are exceeded is emphasized, together with health impact assessments to monitor public health outcomes. The complex local, social, and political aspects that may arise are considered, and so endure engagement and communication with different interest groups. The final part clearly outlines currently unanswered questions and how they should be studied and managed in the future.

scholarly journals Assessment of Switchgrass-Based Bioenergy Supply Using GIS-Based Fuzzy Logic and Network Optimization in Missouri (U.S.A.)

Energies ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 4516
Author(s):  
Huynh Truong Gia Nguyen ◽  
Erik Lyttek ◽  
Pankaj Lal ◽  
Taylor Wieczerak ◽  
Pralhad Burli
Keyword(s):  
Land Use ◽  
Fuzzy Logic ◽  
Network Optimization ◽  
Urban Areas ◽  
Geographical Information Systems ◽  
Large Scale ◽  
Spatial Information ◽  
Geographical Information ◽  
Negative Consequences ◽  
Analytical Approaches

Bioenergy has been globally recognized as one of the sustainable alternatives to fossil fuels. An assured supply of biomass feedstocks is a crucial bottleneck for the bioenergy industry emanating from uncertainties in land-use changes and future prices. Analytical approaches deriving from geographical information systems (GIS)-based analysis, mathematical modeling, optimization analyses, and empirical techniques have been widely used to evaluate the potential for bioenergy feedstock. In this study, we propose a three-phase methodology integrating fuzzy logic, network optimization, and ecosystem services assessment to estimate potential bioenergy supply. The fuzzy logic analysis uses multiple spatial criteria to identify suitable biomass cultivating regions. We extract spatial information based on favorable conditions and potential constraints, such as developed urban areas and croplands. Further, the network analysis uses the road network and existing biorefineries to evaluate feedstock production locations. Our analysis extends previous studies by incorporating biodiversity and ecologically sensitive areas into the analysis, as well as incorporating ecosystem service benefits as an additional driver for adoption, ensuring that biomass cultivation will minimize the negative consequences of large-scale land-use change. We apply the concept of assessing the potential for switchgrass-based bioenergy in Missouri to the proposed methodology.

scholarly journals Drought Hazard Modelling of Klaten Regency Central Java Using AHP and TOPSIS Method

2021 ◽  
Vol 936 (1) ◽  
pp. 012043
Author(s):  
Meiga Nugrahani ◽  
Purnama Budi Santosa
Keyword(s):  
Decision Making ◽  
High Risk ◽  
Geographical Information Systems ◽  
Public Works ◽  
Disaster Mitigation ◽  
Geographical Information ◽  
Topsis Method ◽  
Drought Vulnerability ◽  
Central Java ◽  
The Impact

Abstract According to information of areas at high risk of drought provided by Central Java disaster risk assessment in 2016 - 2020, Klaten Regency is in the top ten at high risk of drought in Central Java. Drought is an annual disaster in this region, which usually occurs during the dry season. The impact of the drought has caused some areas to experience a lack of clean water. For the purpose of disaster mitigation in anticipating and minimizing drought disasters losses, it is necessary to analyze the level of drought with a decision-making system by comparing two methods, namely the AHP with TOPSIS. Both methods are decision-making methods that are composed of various criteria to obtain an alternative sequence of choices. Both the AHP and TOPSIS methods produces weight values and a positive ideal solution value, respectively. These are used as input data in the mapping of drought vulnerability analysis with Geographical Information Systems (GIS). The results of the analysis are visualized with a map that shows the level of drought vulnerability. AHP and TOPSIS method decision making generates the order of the drought classes in predicting the distribution of areas experiencing drought. To validate the model, the authors compare the results of the analysis of drought vulnerability of the two methods with drought data from BPBD (Local Agency for Disaster Prevention) and DPUPR (Public Works and Public Housing Department). The results show that AHP provides better results than TOPSIS based on results validation with BPBD and DPUPR data. By comparing the two models with BPBD data, the results show that the percentage of AHP suitability is higher than TOPSIS at 47,619% and 19,048% respectively.

scholarly journals Using building types and demographic data to improve our understanding and use of urban sprawl simulation

2019 ◽  
Vol 2 ◽  
pp. 1-8
Author(s):  
Mojtaba Eslahi ◽  
Rani El Meouche ◽  
Anne Ruas
Keyword(s):  
Cellular Automata ◽  
Urban Growth ◽  
Urban Areas ◽  
Geographical Information Systems ◽  
Dynamic Models ◽  
Urban Expansion ◽  
Demographic Data ◽  
Population Data ◽  
Geographical Information ◽  
Sleuth Model

<p><strong>Abstract.</strong> Many studies, using various modeling approaches and simulation tools have been made in the field of urban growth. A multitude of models, with common or specific features, has been developed to reconstruct the spatial occupation and changes in land use. However, today most of urban growth techniques just use the historical geographic data such as urban, road and excluded maps to simulate the prospective urban maps. In this paper, adding buildings and population data as urban fabric factors, we define different urban growth simulation scenarios. Each simulation corresponds to policies that are more or less restrictive of space considering what these territories can accommodate as a type of building and as a global population.</p><p>Among the urban growth modeling techniques, dynamic models, those based on Cellular Automata (CA) are the most common for their applications in urban areas. CA can be integrated with Geographical Information Systems (GIS) to have a high spatial resolution model with computational efficiency. The SLEUTH model is one of the cellular automata models, which match the dynamic simulation of urban expansion and could be adapted to morphological model of the urban configuration and fabric.</p><p>Using the SLEUTH model, this paper provides different simulations that correspond to different land priorities and constraints. We used common data (such as topographic, buildings and demography data) to improve the realism of each simulation and their adequacy with the real world. The findings allow having different images of the city of tomorrow to choose and reflect on urban policies.</p>

scholarly journals Cataloguing Wards of Delhi for effective Local Area Planning using Geographical Information Systems

2019 ◽  
Vol 8 (3) ◽  
pp. 3828-3834
Keyword(s):  
Urban Areas ◽  
Geographical Information Systems ◽  
Local Level ◽  
Local Area ◽  
Physical Planning ◽  
Geographical Information ◽  
Constitutional Amendment ◽  
Local Planning ◽  
Operative Planning ◽  
Ward Level

Increased urbanization in an unprecedented manner has resulted in the splitting of urban areas into small divisions for the administrative convenience and effective planning purpose. In India, ward is the smallest administrative unit and has been in attention since 74th Constitutional Amendment Act. This act provided for autonomy to the ULBs to be responsible for the planning, implementation and operation of municipal services at local level. As per the Master Plan of Delhi 2021, all the wards shall have a Local Area Plan (LAP) to meet the needs and aspiration of the local people. The LAP is deciphered at the individual ward level in case of Delhi. There are 272 wards in Delhi and the population of these wards varies from 5000 to 200000. Hence, it is gathered that one approach or framework for urban management at local level may not be suitable for all wards of Delhi and also it is technically not achievable to have 272 individual LAP in the light of both financial and material resources shortage. With this background, the study is conducted and authors have attempted to list the criteria for spatial categorization of wards through literature review with the view to catalogue the wards in Delhi. This will enable planners to formulate strategies suitable for various wards catalogued under one category leading to effective utilization of common resources As a pilot study three important planning criteria - population density, building density and development pattern - were identified from literature studies and Geographical Information System (GIS) application and correlation analysis statistical used over these three criteria to catalogue the wards in Delhi. Consequently, 272 wards of Delhi were catalogued under 9 different categories. The findings are suggestive that physical planning attributes are important tools to define the vast spatial built areas into categories that are more conducive for local planning in comparison to the administrative boundaries delineated on the basis of population only. This may give stimulus to the operative planning at local level and shall enable policy makers and planners to design the strategies which are more efficient in terms of resources, time and are more effective and implementable at ward level. The originality of the study is in the fact that no such study has been conducted in the Indian context that attempts to catalogue built and unbuilt spaces based on physical planning attributes

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