scholarly journals How Do Vegetation Density and Transportation Network Density Affect Crime across an Urban Central-Peripheral Gradient? A Case Study in Kitchener—Waterloo, Ontario

2016 ◽  
Vol 5 (7) ◽  
pp. 118 ◽  
Author(s):  
Yikang Du ◽  
Jane Law
Keyword(s):  
Transportation Network ◽  
Network Density ◽  
Vegetation Density

scholarly journals Efficient Discovery of Periodic-Frequent Patterns in Columnar Temporal Databases

Electronics ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1478
Author(s):  
Penugonda Ravikumar ◽  
Palla Likhitha ◽  
Bathala Venus Vikranth Raj ◽  
Rage Uday Kiran ◽  
Yutaka Watanobe ◽  
...  
Keyword(s):  
Real World ◽  
Pattern Mining ◽  
Transportation Network ◽  
Frequent Pattern Mining ◽  
Temporal Databases ◽  
Frequent Pattern ◽  
Frequent Patterns ◽  
Temporal Database ◽  
First Case

Discovering periodic-frequent patterns in temporal databases is a challenging problem of great importance in many real-world applications. Though several algorithms were described in the literature to tackle the problem of periodic-frequent pattern mining, most of these algorithms use the traditional horizontal (or row) database layout, that is, either they need to scan the database several times or do not allow asynchronous computation of periodic-frequent patterns. As a result, this kind of database layout makes the algorithms for discovering periodic-frequent patterns both time and memory inefficient. One cannot ignore the importance of mining the data stored in a vertical (or columnar) database layout. It is because real-world big data is widely stored in columnar database layout. With this motivation, this paper proposes an efficient algorithm, Periodic Frequent-Equivalence CLass Transformation (PF-ECLAT), to find periodic-frequent patterns in a columnar temporal database. Experimental results on sparse and dense real-world and synthetic databases demonstrate that PF-ECLAT is memory and runtime efficient and highly scalable. Finally, we demonstrate the usefulness of PF-ECLAT with two case studies. In the first case study, we have employed our algorithm to identify the geographical areas in which people were periodically exposed to harmful levels of air pollution in Japan. In the second case study, we have utilized our algorithm to discover the set of road segments in which congestion was regularly observed in a transportation network.

scholarly journals Understanding the Usage Patterns of Bicycle-Sharing Systems to Predict Users’ Demand: A Case Study in Wenzhou, China

2018 ◽  
Vol 2018 ◽  
pp. 1-21 ◽  
Author(s):  
Xiaomei Xu ◽  
Zhirui Ye ◽  
Jin Li ◽  
Mingtao Xu
Keyword(s):  
Cluster Analysis ◽  
Comparative Analysis ◽  
Prediction Models ◽  
Transportation Network ◽  
Back Propagation ◽  
Back Propagation Neural Network ◽  
Demand Prediction ◽  
Usage Patterns ◽  
Accuracy Of Prediction

Bicycle-sharing systems (BSSs) have become a prominent feature of the transportation network in many cities. Along with the boom of BSSs, cities face the challenge of bicycle unavailability and dock shortages. It is essential to conduct rebalancing operations, the success of which largely depend on users’ demand prediction. The objective of this study is to develop users’ demand prediction models based on the rental data, which will serve rebalancing operations. First, methods to collect and process the relevant data are presented. Bicycle usage patterns are then examined from both trip-based aspect and station-based aspect to provide some guidance for users’ demand prediction. After that, the methodology combining cluster analysis, a back-propagation neural network (BPNN), and comparative analysis is proposed to predict users’ demand. Cluster analysis is used to identify different service types of stations, the BPNN method is utilized to establish the demand prediction models for different service types of stations, and comparative analysis is employed to determine if the accuracy of the prediction models is improved by making a distinction among stations and working/nonworking days. Finally, a case study is conducted to evaluate the performance of the proposed methodology. Results indicate that making a distinction among stations and working/nonworking days when predicting users’ demand can improve the accuracy of prediction models.

An improved hazard assessment chart for rock falls in near vertical blocky rock environments

2021 ◽  
Author(s):  
Fhatuwani Sengani ◽  
Mulenga Francois
Keyword(s):  
Slope Angle ◽  
Vegetation Density ◽  
Rock Falls ◽  
Structural Mapping ◽  
Initial Height ◽  
Rockfall Hazard ◽  
Final Destination ◽  
Bedding Planes ◽  
Hazard Rating

Abstract The purpose of the study was to perform rockfall stability analysis and develop an improved rockfall hazard matrix chart using the R518 road in Limpopo as the case study. The study entailed structural mapping, wedge simulation using stereonet plots. The RocFall software was then used to identify the parameters that influence the occurrence of rockfall. The software was also used to monitor the variations in the kinetic energy of rolling, bouncing or falling rocks. The effects of the initial height and velocity of falling rocks on the final destination of fragments were also explored. Results showed that the selected area along the R518 road consists of joints and bedding planes. These features weaken the rock mass and create wedges that can potentially fall. Simulations with RocFall, on the other hand, indicated that slope height, vegetation density, slope angle, the velocity of the falling rock largely contribute to the extent that the broken rock could reach. From the empirical and numerical findings, an improved rockfall hazard rating chart was proposed. The chart was found to be suitable for the rating of level of rockfall hazard along highways and roads.

The Use of the Land Survey Record to Assess Changes in Vegetation Structure. A Case Study From the Darling Downs, Queensland, Australia.

1998 ◽  
Vol 20 (1) ◽  
pp. 132 ◽  
Author(s):  
RJ Fensham ◽  
JE Holman
Keyword(s):  
Vegetation Structure ◽  
Canopy Cover ◽  
Vegetation Density ◽  
Crown Cover ◽  
Standard Application ◽  
Land Survey ◽  
Minor Vegetation ◽  
Structural Category ◽  
Historical Photographs

Fifteen references to vegetation structure from the historical land survey record for the eastern Darling Downs were calibrated with historical photographs to determine the use of the surveyors' structural terminology (Open: 'open', 'light': Dense: 'heavy', 'thick', 'dense'). Sites with less than 40% canopy cover were only described by terms included within the Open category, and sites with greater than 50% canopy cover were only described by terms included within the Dense category. These results provide calibrations of the surveyors' structural terminology indicating terms were unambiguously applied outside the 40-50% canopy cover range. The use of corner tree distances as an absolute measure of vegetation density is warned against because corner trees had to meet certain criteria and were not necessarily the nearest tree to any corner. However, the distance from allotment corners to "corner trees" provided a measure of the relative use of the surveyor's structural epithets and is consistent with standard application among their fraternity. Survey records dating from 1864-1910 were compared with the structure of existing remnants (projective crown cover measured from recent 1:25,000 aerial photography) to assess changes in vegetation structure. The analysis suggests that 88% of the 34 sites included in the analysis have not changed from the broad structural category that was assigned by the surveyors. Using the assumptions developed by this study, two sites were assessed as having thickened substantially. These results suggest that only minor vegetation thickening has occurred in the Darling Downs since the early land surveys. This conclusion is supported by direct comparison of the historical photographs with existing remnants. indicating that only one site out of 17 has thickened substantially.

scholarly journals Discrete Robustness Optimization on Emergency Transportation Network Based on Prospect Theory

2019 ◽  
Vol 2019 ◽  
pp. 1-18 ◽  
Author(s):  
Zheng-kun Zhang ◽  
Chang-feng Zhu ◽  
Qing-rong Wang ◽  
Jia-shan Yuan
Keyword(s):  
Genetic Algorithm ◽  
Prospect Theory ◽  
Decision Maker ◽  
Transportation Network ◽  
Optimal Solution ◽  
Improved Genetic Algorithm ◽  
Decision Behavior ◽  
Bidirectional Search ◽  
Robustness Optimization

This paper focuses on the discrete robustness optimization of emergency transportation network with the consideration of timeliness and decision behavior of decision-maker under the limited rationality. Based on a situation that the nearer to disaster area, the higher probability of time delay, prospect theory is specially introduced to reflect the subjective decision behavior of decision-maker. Then, a discrete robustness optimization model is proposed with the purpose of the better timeliness and robustness. The model is based on the emergency transportation network with multistorage centers and multidisaster points. In order to obtain the optimal solution, an improved genetic algorithm is designed by introducing a bidirectional search strategy based on a newfangled path cluster to obtain specific paths that connect each storage centers and each disaster points. Finally, a case study is exhibited to demonstrate the reasonability of the model, theory, and algorithm. The result shows that the path cluster with the better timeliness and robustness can be well obtained by using the prospect theory and improved genetic algorithm. The analysis especially reveals that the robustness is correspondent to the risk aversion in prospect theory.

Is it Possible to Manage and Plan Co-Modal Freight Transport Without a Centralised System?

2012 ◽  
Vol 3 (2) ◽  
pp. 25-39 ◽  
Author(s):  
Thomas Zunder ◽  
Hans Westerheim ◽  
Ronald Jorna ◽  
Jan Tore Pedersen
Keyword(s):  
Transportation Network ◽  
Freight Transport ◽  
The European Union ◽  
Transport Service ◽  
Software Methodology ◽  
Business Cases ◽  
Small Set ◽  
Research Gap ◽  
Transport Domain

The European Union has looked to develop ICT systems that are open and interoperable. Through the case study of the Freightwise research project a research gap was identified: Is it possible to manage and plan co-modal freight transport without a centralised system? The adoption of software methodology and business process mapping enables the development and the validation of the Freightwise Framework for co-modal freight transport. The Framework divides the freight transport domain into manageable sub-domains and defines the main roles that need to interact as well as the necessary interactions in between these domains. The main roles identified are: the Transport User and the Transport Service Provider, supported by the Transportation Network Manager and the Transport Regulator. The Framework also defines a generic specification of a transport service and a small set of sufficient and necessary information objects that need to be exchanged between the four main roles. This paper explores the goal, context, methodologies utilised, results and validation in multiple business cases. The paper ends with reflections on how the results may be developed and implemented.

Clark as an Alternative Destination for Warehouse Storage in Manila, Philippines

2015 ◽  
Vol 14 (1) ◽  
Author(s):  
LOK TAK MING JAFY
Keyword(s):  
Information Sources ◽  
Transportation Network ◽  
Demographic Characteristics ◽  
Destination Image ◽  
Similar Argument ◽  
Economic Activities ◽  
Storage Location ◽  
Travelling Time ◽  
Warehouse Storage

This paper is to apply the concept of the destination image to a decision on warehouse storage location. With a proper transportation network, people in Manila could reach Clark in one to one and a half hours.  However, currently, the customers in Manila are reluctant to use the warehouse services in Clark.  One of the main concerns is on the unexpected travelling time. The objective of this paper is to explore whether people will consider Clark as an alternative destination for warehouse storage in Manila if there is a proper transportation network. The results of the three case studies confirm the model of the formation of the destination image being the information sources, experience, psychologically nature and socio-demographic characteristics. The results also confirm the influence of the linked transportation network to Clark as a destination image. It is concluded that propositions are supported, and literal replication is expected. With a properly linked transportation network, consumers are willing to consider Clark as a warehouse storage location. With a similar argument, Clark could be considered for other business and other economic activities if there is properly linked transportation network between Clark and Manila. Keywords- Destination image, linked transportation network, case study, Manila, Clark

UrbanAccess: Generalized Methodology for Measuring Regional Accessibility with an Integrated Pedestrian and Transit Network

2017 ◽  
Vol 2653 (1) ◽  
pp. 35-44 ◽  
Author(s):  
Samuel D. Blanchard ◽  
Paul Waddell
Keyword(s):  
San Francisco ◽  
San Francisco Bay Area ◽  
Transportation Network ◽  
Computationally Efficient ◽  
New Methods ◽  
Bay Area ◽  
Transit Accessibility ◽  
Fine Spatial Resolution ◽  
Operational Schedule

Measures of accessibility have long been an important metric in regional transportation planning and modeling. However, new methods are needed to provide computationally efficient, multiscale, free, transparent, and customizable tools that harness open and disparate sources of transportation network data at fine spatial resolution over large geographic extents. This research presents a new open source tool, UrbanAccess, which uses a generalized and scalable methodology to measure transit accessibility with a multimodal network comprising both pedestrian and operational schedule transit networks at a fine spatial scale over large metropolitan extents. A typical use for this tool is illustrated in a case study that characterizes regional transit accessibility in the San Francisco Bay Area in California.

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