Research on Urban Ecological Network Under the Threat of Road Networks—A Case Study of Wuhan

The creation of a road network can lead to the fragmentation and reduction of the connectivity of the ecological habitat. The study of urban ecological networks under threat from rapidly developing road networks is of great significance in understanding the changes in urban ecological processes and in constructing a reasonable ecological network. Spatial syntax is a linear space analysis method based on graph theory. Taking Wuhan city as an example and adopting spatial syntax to quantify road network threat factors, two resistance surfaces are established based on land use type assignment and overlapping road network threat factor assignment. The ecological environment under two scenarios is constructed by combining the MSPA (Morphological Spatial Pattern Analysis) method and MCR (Minimal Cumulative Resistance) model to comprehensively evaluate the network. Results demonstrate that spatial syntax can effectively describe the spatial characteristics of the road network. The average resistance value of the study area increases by 15.94%, the length of corridor increases by 37.9 km, the energy consumption of biological and material exchanges increases, and the resistance increases. To a certain extent, the model reflects the impact of road network threats on ecological processes. The results are useful in identifying the impact of human activities on ecological processes and provide a reference point for the construction of urban ecological security patterns.

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ANALISIS PENGARUH PEMBANGUNAN JALAN LAYANG JANTI TERHADAP PERKEMBANGAN TATA RUANG KAWASAN JANTI STUDI KASUS : KAWASAN JANTI, DESA CATURTUNGGAL, KABUPATEN SLEMAN, D. I. YOGYAKARTA

Jurnal Arsitektur KOMPOSISI ◽

10.24002/jars.v10i4.1089 ◽

2017 ◽

Vol 11 (3) ◽

pp. 255

Author(s):

Jeky El Boru

Keyword(s):

Road Network ◽

Open Space ◽

Qualitative Description ◽

Analysis Method ◽

Open Spaces ◽

The Road ◽

Before And After ◽

Linkage Method ◽

The Impact ◽

Parking Place

Abstract: This research aims to analyze the impact of Janti Flyover Construction toward the growth of layout at Janti Urban Area, including structured space, open space, and linkage. Method used for data collecting are observation, air photograph monitoring, and interview, whereas the analysis method is qualitative description, which is the superimposed method of two layers, that are the layout condition before and after flyover construction. The result shows that the impact of Janti Flyover construction can be seen on building mass (solid), the increasing number of open spaces, including the road network, parking place, and park, whereas the relation between spaces, visually and structurally, can be seen on the growth of buildings which have new shapes and styles, therefore the performance of the overall building does not have a proportional shape. Considering Janti Street at the collective relation, its role is getting stronger as the main frame road network.Keywords: Flyover construction, layout changing, Janti AreaAbstrak: Penelitian ini bertujuan untuk menganalisis pengaruh pembangunan Jalan Layang Janti terhadap perkembangan tata ruang Kawasan Janti, meliputi ruang terbangun, ruang terbuka, serta hubungan antar ruang (“linkage”). Metode pengumpulan data dilakukan melalui observasi, pengamatan foto udara, dan wawancara; sedangkan metode analisis melalui deskripsi secara kualitatif yang berupa “superimposed method” dari dua lapisan kondisi lahan, yakni kondisi tata ruang sebelum dan sesudah pembangunan jalan layang. Hasil penelitian menunjukkan bahwa pengaruh pembangunan Jalan Layang Janti terdapat pada massa bangunan (“solid”), pertambahan ruang terbuka yang berupa jaringan jalan, parkir, dan taman; sedangkan pada hubungan antar ruang ̶ secara visual dan struktural ̶ yakni tumbuhnya bangunan dengan bentuk dan gaya baru, sehingga bentuk tampilan bangunan secara keseluruhan tidak proporsional. Pada hubungan kolektif, Jalan Janti semakin kuat perannya sebagai kerangka utama jaringan jalan.Kata kunci : Pembangunan jalan layang, tata ruang, Kawasan Janti

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Impact of Road Network Topology on Public Transportation Development

Wireless Communications and Mobile Computing ◽

10.1155/2021/6209592 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Minzhi Chen ◽

Fan Wu ◽

Min Yin ◽

Jiangang Xu

Keyword(s):

Public Transportation ◽

Road Network ◽

Road Networks ◽

Urban Road Network ◽

Urban Road ◽

The Road ◽

Layout Structure ◽

Per Capita ◽

Transportation Development ◽

The Impact

Planning of road networks is fundamental for public transportation. The impact of road network density on public transportation has been extensively studied, but few studies in this regard involved evaluation indicators for connectivity and layout of road networks. With 29 cities in China as the study cases, this paper quantifies the layout structure of the road network based on the network’s betweenness centralization and establishes a multivariate linear regression model to perform regression of the logarithm of the frequency of per capita public transportation on betweenness centralization. It is found in the present work that there is a significant correlation between the layout structure of an urban road network and the residents’ utilization degree of public transportation. A greater betweenness centralization of the urban road network, namely a more centralized road network, means a higher frequency of per capita public transportation of urban residents and a higher degree of the residents’ utilization of public transportation. In the development of public transportation, centralized and axial-shaped layout structures of road networks can be promoted to improve the utilization of public transportation.

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Influence Models of Urban Road Network Operation Performance Base on Spatial Autocorrelation Theory

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.253-255.1922 ◽

2012 ◽

Vol 253-255 ◽

pp. 1922-1929

Author(s):

Jian Cheng Weng ◽

Wen Jie Zou ◽

Jian Rong

Keyword(s):

Spatial Autocorrelation ◽

Road Network ◽

Road Networks ◽

Operation Performance ◽

Urban Road Network ◽

Spatial Characteristics ◽

Urban Road ◽

The Road ◽

Network Operation ◽

The Impact

In order to better identify the spatial influence between adjacent parts of road networks, the paper introduces the spatial autocorrelation theory in evaluating the operation performance of urban road networks. The research proposes several spatial correlation validation indicators to verify the spatial characteristics among the road networks. Based on the analysis of spatial characteristics, the relationship between operation performance and influencing factors under the impact of spatial effect is examined. Furthermore, a spatial autocorrelation based influence models at three traffic flow levels is developed by using the data from a partial urban road network in Beijing. The model analysis shows that the spatial autocorrelation model is more effective in analyzing the urban road network operation performance under the influence of various factors. This model will be beneficial in identifying traffic network problems and improving traffic operations of the urban road network.

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Urban Road Network Emergency: An Integrative Vulnerability Identification Method

Complexity ◽

10.1155/2021/6325578 ◽

2021 ◽

Vol 2021 ◽

pp. 1-20

Author(s):

Huaikun Xiang

Keyword(s):

Network Traffic ◽

Road Network ◽

Road Networks ◽

Likelihood Method ◽

Survey Method ◽

Urban Road Network ◽

Urban Road ◽

The Road ◽

Identification Method ◽

The Impact

The vulnerability of an urban road network is affected by many factors, such as internal road network layout, network structure strength, and external destructive events, which have great uncertainty and complexity. Thus, there is still no unified and definite vulnerability analysis scheme available to cities. This paper proposes an integrative vulnerability identification method for urban road networks, which mainly relates to the vulnerability connotation and characteristics analysis of urban road networks during emergency, and vulnerability comprehensive evaluation indices design based on urban road network connectivity, traffic efficiency and performance, and an empirical study on a vulnerability identification method of an urban road network. In the empirical case, a real road network and traffic operation data were used from Science and Technology Park of Shenzhen City, China. In the context of one certain emergency scenario, the stated preference survey method and maximum likelihood method are used to solve the road users’ random travel choice behavior parameters; subsequently, based on the traffic equilibrium distribution prediction, the traffic vulnerability identification methods of the road network in this region were verified before and after the emergency. The method presented here not only considers the impact of network topology changes on road network traffic function during emergency but also considers the impact of dynamic changes in road network traffic demand on vulnerability; therefore, it is closer to the actual distribution of urban road network traffic vulnerability.

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Optimizing The Functional Performance of Road Network using Vulnerability Assessment to Cope with Unforeseen Road Incidents

Journal of the Civil Engineering Forum ◽

10.22146/jcef.3598 ◽

2021 ◽

pp. 67-80

Author(s):

Mukhammad Rizka Fahmi Amrozi ◽

Raihan Pasha Isheka

Keyword(s):

Road Network ◽

Functional Performance ◽

Road Networks ◽

Travel Speed ◽

Vulnerability Index ◽

Urban Road ◽

The Road ◽

Road Performance ◽

Criticality Index ◽

The Impact

An Urban Road network is often used for multipurpose trips, due to their transportation functions, such as attractiveness and orientation, as well as social, ecological, and economic features. In Indonesia, road incidents have reportedly increased during the last decade because of a higher frequency of natural hazards, accidents, and on-street mass demonstrations. These incidents are found to degrade or terminate road access, forcing users to utilize alternative routes and decreasing the service performance in adjacent directions. Due to the unexpected occurrences at any location and time, there is a need to investigate the impact of random incidents on road performances. Several accessibility indexes have also been used to evaluate the vulnerability of road networks. However, this is less practical in Indonesia, with the road authority using functional performances as the indicator. This indicates the need for an index to be developed based on road performance parameters. Therefore, this study aims to develop a road performance-based vulnerability index known as the RCI (Road Criticality Index). Combined with a traffic simulation tool, this system is used as an alternative index to assess vulnerabilities, by identifying the road(s) providing worse consequences due to unforeseen incidents. This simulation was conducted by using the PTV Visum, assuming a road section is closed due to the worst incident scenarios. The result showed that the RCI offered a more comprehensive assessment than the existing indicator (volume capacity ratio). The RCI included travel speed and mobility components for evaluating both local and global road performances. With the knowledge of the most vulnerable locations and their consequences, road authorities can prioritize maintenance and development strategies based on the criticality index. Also, preventive measures should be conducted to mitigate risk under a constrained budget. This methodology can be applied to sustainably enhance the resilience of urban road networks.

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Modeling of Emergency Supply Scheduling Problem Based on Reliability and Its Solution Algorithm under Variable Road Network after Sudden-Onset Disasters

Complexity ◽

10.1155/2020/7501891 ◽

2020 ◽

Vol 2020 ◽

pp. 1-15 ◽

Cited By ~ 12

Author(s):

Tinggui Chen ◽

Shiwen Wu ◽

Jianjun Yang ◽

Guodong Cong ◽

Gongfa Li

Keyword(s):

Road Network ◽

Road Networks ◽

Sudden Onset ◽

The Road ◽

Bee Colony ◽

Proposed Model ◽

Effectiveness And Efficiency ◽

In Transit ◽

Emergency Supply

It is common that many roads in disaster areas are damaged and obstructed after sudden-onset disasters. The phenomenon often comes with escalated traffic deterioration that raises the time and cost of emergency supply scheduling. Fortunately, repairing road network will shorten the time of in-transit distribution. In this paper, according to the characteristics of emergency supplies distribution, an emergency supply scheduling model based on multiple warehouses and stricken locations is constructed to deal with the failure of part of road networks in the early postdisaster phase. The detailed process is as follows. When part of the road networks fail, we firstly determine whether to repair the damaged road networks, and then a model of reliable emergency supply scheduling based on bi-level programming is proposed. Subsequently, an improved artificial bee colony algorithm is presented to solve the problem mentioned above. Finally, through a case study, the effectiveness and efficiency of the proposed model and algorithm are verified.

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A Parallel-Computing Approach for Vector Road-Network Matching Using GPU Architecture

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi7120472 ◽

2018 ◽

Vol 7 (12) ◽

pp. 472 ◽

Cited By ~ 1

Author(s):

Bo Wan ◽

Lin Yang ◽

Shunping Zhou ◽

Run Wang ◽

Dezhi Wang ◽

...

Keyword(s):

Road Network ◽

Large Scale ◽

Graphics Processing Unit ◽

Road Networks ◽

Processing Unit ◽

Data Partition ◽

Matching Method ◽

The Road ◽

Central Processing ◽

Relaxation Matching

The road-network matching method is an effective tool for map integration, fusion, and update. Due to the complexity of road networks in the real world, matching methods often contain a series of complicated processes to identify homonymous roads and deal with their intricate relationship. However, traditional road-network matching algorithms, which are mainly central processing unit (CPU)-based approaches, may have performance bottleneck problems when facing big data. We developed a particle-swarm optimization (PSO)-based parallel road-network matching method on graphics-processing unit (GPU). Based on the characteristics of the two main stages (similarity computation and matching-relationship identification), data-partition and task-partition strategies were utilized, respectively, to fully use GPU threads. Experiments were conducted on datasets with 14 different scales. Results indicate that the parallel PSO-based matching algorithm (PSOM) could correctly identify most matching relationships with an average accuracy of 84.44%, which was at the same level as the accuracy of a benchmark—the probability-relaxation-matching (PRM) method. The PSOM approach significantly reduced the road-network matching time in dealing with large amounts of data in comparison with the PRM method. This paper provides a common parallel algorithm framework for road-network matching algorithms and contributes to integration and update of large-scale road-networks.

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Road Networks Winter Risk Estimation Using On-Board Uncooled Infrared Camera for Surface Temperature Measurements over Two Lanes

International Journal of Geophysics ◽

10.1155/2011/514970 ◽

2011 ◽

Vol 2011 ◽

pp. 1-8 ◽

Cited By ~ 3

Author(s):

M. Marchetti ◽

M. Moutton ◽

S. Ludwig ◽

L. Ibos ◽

V. Feuillet ◽

...

Keyword(s):

Data Analysis ◽

Road Network ◽

Risk Estimation ◽

Risk Index ◽

Road Networks ◽

Infrared Camera ◽

Atmospheric Parameters ◽

The Road ◽

Measurement Rate

Thermal mapping has been implemented since the late eighties to establish the susceptibility of road networks to ice occurrence with measurements from a radiometer and some atmospheric parameters. They are usually done before dawn during wintertime when the road energy is dissipated. The objective of this study was to establish if an infrared camera could improve the determination of ice road susceptibility, to build a new winter risk index, to improve the measurements rate, and to analyze its consistency with seasons and infrastructures environment. Data analysis obtained from the conventional approved radiometer sensing technique and the infrared camera has shown great similarities. A comparison was made with promising perspectives. The measurement rate to analyse a given road network could be increased by a factor two.

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Analysis of Traffic Evolution on Road Networks of a Roundabout

Journal of Applied Mathematics ◽

10.1155/2020/3959613 ◽

2020 ◽

Vol 2020 ◽

pp. 1-18

Author(s):

Tolesa Hundesa Muleta ◽

Legesse Lemecha Obsu

Keyword(s):

Traffic Congestion ◽

Road Network ◽

Road Networks ◽

Point Of View ◽

Traffic Dynamics ◽

Demand And Supply ◽

The Road ◽

On The Road ◽

Detailed Mathematical Analysis ◽

Control Traffic

In this paper, the analyses of traffic evolution on the road network of a roundabout having three entrances and three exiting legs are conducted from macroscopic point of view. The road networks of roundabouts are modeled as a merging and diverging types 1×2 and 2×1 junctions. To study traffic evolution at junction, two cases have been considered, namely, demand and supply limited cases. In each case, detailed mathematical analysis and numerical tests have been presented. The analysis in the case of demand limited showed that rarefaction wave fills the portion of the road network in time. In the contrary, in supply limited case, traffic congestion occurs at merging junctions and shock wave propagating back results in reducing the performance of a roundabout to control traffic dynamics. Also, we illustrate density and flux profiles versus space discretization at different time steps via numerical simulation with the help of Godunov scheme.

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A Privacy-Preserving Location-Based System for Continuous Spatial Queries

Mobile Information Systems ◽

10.1155/2016/6182769 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 4

Author(s):

Doohee Song ◽

Kwangjin Park

Keyword(s):

Road Network ◽

Road Networks ◽

Nearest Neighbors ◽

Privacy Preserving ◽

Spatial Queries ◽

The Road ◽

Mobile Clients ◽

Previous Location

K-anonymization generated a cloaked region (CR) that was K-anonymous; that is, the query issuer was indistinguishable from K-1 other users (nearest neighbors) within the CR. This reduced the probability of the query issuer’s location being exposed to untrusted parties (1/K). However, location cloaking is vulnerable to query tracking attacks, wherein the adversary can infer the query issuer by comparing the two regions in continuous LBS queries. This paper proposes a novel location cloaking method to resist this attack. The target systems of the proposed method are road networks where the mobile clients’ trajectories are fixed (the road network is preknown and fixed, instead of the trajectories), such as subways, railways, and highways. The proposed method, called adaptive-fixed K-anonymization (A-KF), takes this issue into account and generates smaller CRs without compromising the privacy of the query issuer’s location. Our results show that the proposed A-KF method outperforms previous location cloaking methods.

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