Assessment of Road Network Connectivity using Graph Theory in the Chehel-Chai Watershed, Golestan Province

The transport network of cities can be represented as a complex of streets and passages, as well as elements of public transport infrastructure unconnected with the street and road network. It is reasonable to represent the real network in the form of a simplified network based on graph theory to analyze the properties of the transport network. There are various methods of network connectivity assessment, including those based on various indices. According to all indicators in the street and road network of the city of Petrozavodsk it is necessary to increase the number of units. The implementation of recommendations for changes of the street and road network of the city of Petrozavodsk will reduce traffic congestion, the number of accidents and transport expenses. It is recommended to use the proposed method to assess and improve the street and road network of cities.

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MPA network design based on graph theory and emergent properties of larval dispersal

Marine Ecology Progress Series ◽

10.3354/meps13399 ◽

2020 ◽

Vol 650 ◽

pp. 309-326

Author(s):

A Ospina-Alvarez ◽

S de Juan ◽

J Alós ◽

G Basterretxea ◽

A Alonso-Fernández ◽

...

Keyword(s):

Graph Theory ◽

Network Design ◽

Early Life ◽

Larval Dispersal ◽

Network Connectivity ◽

Life Stages ◽

Early Life Stages ◽

Larval Connectivity ◽

The Impact ◽

Mpa Network

Despite the recognised effectiveness of networks of marine protected areas (MPAs) as a biodiversity conservation instrument, MPA network design frequently disregards the importance of connectivity patterns. In the case of sedentary marine populations, connectivity stems not only from the stochastic nature of the physical environment that affects dispersal of early life stages, but also from the spawning stock attributes that affect reproductive output (e.g. passive eggs and larvae) and survivorship. Early life stages are virtually impossible to track in the ocean. Therefore, numerical ocean current simulations coupled with egg and larval Lagrangian transport models remain the most common approach for the assessment of marine larval connectivity. Inferred larval connectivity may differ depending on the type of connectivity considered; consequently, the prioritisation of sites for the conservation of marine populations might also differ. Here, we introduce a framework for evaluating and designing MPA networks based on the identification of connectivity hotspots using graph theoretic analysis. As a case study, we used a network of open-access areas and MPAs off Mallorca Island (Spain), and tested its effectiveness for the protection of the painted comber Serranus scriba. Outputs from network analysis were used to (1) identify critical areas for improving overall larval connectivity, (2) assess the impact of species’ biological parameters in network connectivity and (3) explore alternative MPA configurations to improve average network connectivity. Results demonstrate the potential of graph theory to identify non-trivial egg/larval dispersal patterns and emerging collective properties of the MPA network, which are relevant for increasing protection efficiency.

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Testing the Impact of Road Network Connectivity on Criminal Lethality

Homicide Studies ◽

10.1177/1088767918754307 ◽

2018 ◽

Vol 22 (3) ◽

pp. 277-295 ◽

Cited By ~ 2

Author(s):

Aaron C. Poole ◽

James C. McCutcheon ◽

Kayla Toohy ◽

Bert Burraston

Keyword(s):

Road Network ◽

Reporting System ◽

Explanatory Variable ◽

Network Connectivity ◽

Google Earth ◽

Community Survey ◽

Data Sources ◽

American Community Survey ◽

Positive Outcomes ◽

The Impact

Increased road network connectivity has been linked to more positive outcomes among all health outcomes. Road network connectivity has yet to be tested in association with specifically criminal lethality. The current study looks to incorporate road network connectivity as an explanatory variable for criminal lethality. Data on Road Network Connectivity and Criminal Lethality are gathered for 190 cities. Data sources include the National Incident-Based Reporting System (NIBRS), 2010 Census, 2010 American Community Survey, Google Earth, and Census Topologically Integrated Geographic Encoding and Referencing (TIGER) files. The data demonstrate that a city’s road network connectivity is related to decreases in the rates of lethality among assaults. Implications of this finding are discussed.

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Graph Theory-Based Brain Network Connectivity Analysis and Classification of Alzheimer’s Disease

International Journal of Image and Graphics ◽

10.1142/s021946782240006x ◽

2021 ◽

Author(s):

A. Thushara ◽

C. Ushadevi Amma ◽

Ansamma John

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Graph Theory ◽

Neurodegenerative Disorder ◽

Brain Networks ◽

Network Connectivity ◽

Brain Regions ◽

Brain Network ◽

Fiber Tracts ◽

The Brain

Alzheimer’s Disease (AD) is basically a progressive neurodegenerative disorder associated with abnormal brain networks that affect millions of elderly people and degrades their quality of life. The abnormalities in brain networks are due to the disruption of White Matter (WM) fiber tracts that connect the brain regions. Diffusion-Weighted Imaging (DWI) captures the brain’s WM integrity. Here, the correlation betwixt the WM degeneration and also AD is investigated by utilizing graph theory as well as Machine Learning (ML) algorithms. By using the DW image obtained from Alzheimer’s Disease Neuroimaging Initiative (ADNI) database, the brain graph of each subject is constructed. The features extracted from the brain graph form the basis to differentiate between Mild Cognitive Impairment (MCI), Control Normal (CN) and AD subjects. Performance evaluation is done using binary and multiclass classification algorithms and obtained an accuracy that outperforms the current top-notch DWI-based studies.

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Corrigendum to “Methods for analyzing road network bottleneck and bottleneck chain corridor under disastrous events using graph theory” [Saf. Sci. 118 (2019) 925–932]

Safety Science ◽

10.1016/j.ssci.2019.07.046 ◽

2020 ◽

Vol 121 ◽

pp. 697

Author(s):

Qi-kai Qu ◽

Fu-jian Chen ◽

Xiao-jian Zhou

Keyword(s):

Graph Theory ◽

Road Network

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The Study of How Open Community Based on Combination Weighting Method Influence on Road Capacity

Modern Applied Science ◽

10.5539/mas.v11n6p15 ◽

2017 ◽

Vol 11 (6) ◽

pp. 15 ◽

Cited By ~ 1

Author(s):

Zhuhui He ◽

Rui Liao ◽

Longlong Wang

Keyword(s):

Road Network ◽

Comprehensive Evaluation ◽

Positive Impact ◽

Evaluation Model ◽

Network Connectivity ◽

Entropy Weight ◽

Weighting Method ◽

Linear Coefficient ◽

The Road ◽

Road Capacity

The paper studies whether the opening of community can improve the road capacity. First of all, based on the consideration of road space and traffic quality, the evaluation indexes are: road network density, road network connectivity, non-linear coefficient, traffic volume of main road beside community, delay time of intersection, travel time consumption and vehicle accessibility. Secondly, the weight of the index is calculated by the method of relative comparison, the variation coefficient method and the entropy weight method. Then, we sort the three weights, using the correlated coefficient and degree of spearman rank to combine the three weights, so as to get combined weights of various index and achieve the effect which makes good use of the method. Finally, we combine indicators and weights, establish a comprehensive evaluation model, and assess the road capacity before and after the opening of the road. Through the calculation, it is found that the comprehensive evaluation index after the opening of the community is higher than that before the opening, that is, the positive impact on the surrounding roads.

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Reliability Evaluation Model of Highway Network Connectivity in Western Mountainous Area

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.361-363.2134 ◽

2013 ◽

Vol 361-363 ◽

pp. 2134-2139

Author(s):

Xian Guang Wang ◽

Xiao Nian Sun ◽

Ming Wen Wang

Keyword(s):

Road Network ◽

Evaluation Model ◽

Network Connectivity ◽

Reliability Evaluation ◽

Mountainous Area ◽

The Road ◽

Highway Network ◽

Planning And Construction ◽

Important Significance ◽

Highway System

The research on the reliability of highway network connectivity has important significance in the western region. According to the characteristics of western mountainous highway, this paper sets up the reliability evaluation idea of highway network connectivity from the section to the route, from the route to the road network, and establishes the reliability evaluation model of the connectivity of section, route and road network based on the analysis of highway unit reliability. The research results provide the theoretical basis for western mountainous road network planning and construction as well as disaster-resistance and disaster-prevention countermeasures of highway system.

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