1,721,562 research outputs found
Demonstrator of a Cost/Utility Function Taking Activity-based Information into Account - Deliverable 4.2
No full textThis deliverable as part of WP 4 task 4.2.1 is having three major aims. Firstly, it presents a
demonstration of an Activity-based model (FEATHERS) and its supply counterpart MATSIM, to
predict activity-travel schedules of individuals and then execute them to determine the traffic
volume on the road network. The deliverable provides a comprehensive description of cost/utility
functions (i.e. functions that incorporates a variety of variables and associate them with travel
decisions) to ascertain the type of policies/interventions or TDMs that can be assessed within
the developed simulator. The cost/utility function with FEATHERS are in the form of decision
tree models and within MATSIM it is represented as a scoring function of a plan based on a
variety of built-in parameters. The deliverable also provides a guideline methodology about what
possible changes in the system need to be made in order to run a particular policy scenario.
As a second major aim, the deliverable presents a criterion in order to select policies to be
tested via the developed simulator. The criterion is mainly following the earlier deliverables
where a complete review of such policies is provided that are found most effective in relation
with improving the air quality of a certain region. Furthermore, support from iSCAPE city profiles
that also presents the mobility situations of each city is taken to finalize the list of policies. These
city profiles are based on the opinions of the city stakeholders and its citizens. In addition to this,
the selection of policies is also based on the state-of-the art transport policy literature, which
emphasizes more towards low-cost and easily implementable policies. Limitations of the
simulator are also considered in finalizing the policy list. Restriction on car accessibility,
enhancement of public transport infrastructure, fare reduction of public transport, road pricing,
strict parking regulations, telecommuting and opening hours of activity locations are presented
as key policies that have significant potential to bring positive change in the environment as well
as individual’s health.
Lastly, some of these policies are implemented in the simulator along with the presentation of
aggregate results. Before the policy implementation, results of the base scenario are validated
with available traffic counts, which are found plausible as goodness-of-fit measure is more than
0.7 in all validation cases. Results of the policies are also in line with the expectations. However,
outputs can be disaggregated in a variety of different ways to discover more meaningful insights
about the impact of policies. The aggregate outputs presented in this deliverable is for
demonstration purpose and to provide evidence regarding the capabilities of the simulator.
For the next steps of WP 4, this deliverable can provide a profound basis to ascertain few policy
scenarios to be run for a selected iSCAPE cities within a light version of this simulator whose
development is ongoing as a part of task 4.2.2. Partners in iSCAPE cities are encouraged to
discuss this deliverable with city stakeholders to come up with one or two policy scenarios that
can be implemented for assessment of their impacts. Furthermore, in order to achieve the
overall objectives of WP 4, the results obtained from the policy implementation will be further
incorporated in emissions and air quality dispersion model to identify their impact on improving
overall air quality for selected cities. These results can help in exposure assessments and to
ascertain health impacts for various groups of population, which is required to be reported in WP
7 deliverables
Demonstrator of a Cost/Utility Function Taking Activity-based Information into Account - Deliverable 4.2
No full textThis deliverable as part of WP 4 task 4.2.1 is having three major aims. Firstly, it presents a
demonstration of an Activity-based model (FEATHERS) and its supply counterpart MATSIM, to
predict activity-travel schedules of individuals and then execute them to determine the traffic
volume on the road network. The deliverable provides a comprehensive description of cost/utility
functions (i.e. functions that incorporates a variety of variables and associate them with travel
decisions) to ascertain the type of policies/interventions or TDMs that can be assessed within
the developed simulator. The cost/utility function with FEATHERS are in the form of decision
tree models and within MATSIM it is represented as a scoring function of a plan based on a
variety of built-in parameters. The deliverable also provides a guideline methodology about what
possible changes in the system need to be made in order to run a particular policy scenario.
As a second major aim, the deliverable presents a criterion in order to select policies to be
tested via the developed simulator. The criterion is mainly following the earlier deliverables
where a complete review of such policies is provided that are found most effective in relation
with improving the air quality of a certain region. Furthermore, support from iSCAPE city profiles
that also presents the mobility situations of each city is taken to finalize the list of policies. These
city profiles are based on the opinions of the city stakeholders and its citizens. In addition to this,
the selection of policies is also based on the state-of-the art transport policy literature, which
emphasizes more towards low-cost and easily implementable policies. Limitations of the
simulator are also considered in finalizing the policy list. Restriction on car accessibility,
enhancement of public transport infrastructure, fare reduction of public transport, road pricing,
strict parking regulations, telecommuting and opening hours of activity locations are presented
as key policies that have significant potential to bring positive change in the environment as well
as individual’s health.
Lastly, some of these policies are implemented in the simulator along with the presentation of
aggregate results. Before the policy implementation, results of the base scenario are validated
with available traffic counts, which are found plausible as goodness-of-fit measure is more than
0.7 in all validation cases. Results of the policies are also in line with the expectations. However,
outputs can be disaggregated in a variety of different ways to discover more meaningful insights
about the impact of policies. The aggregate outputs presented in this deliverable is for
demonstration purpose and to provide evidence regarding the capabilities of the simulator.
For the next steps of WP 4, this deliverable can provide a profound basis to ascertain few policy
scenarios to be run for a selected iSCAPE cities within a light version of this simulator whose
development is ongoing as a part of task 4.2.2. Partners in iSCAPE cities are encouraged to
discuss this deliverable with city stakeholders to come up with one or two policy scenarios that
can be implemented for assessment of their impacts. Furthermore, in order to achieve the
overall objectives of WP 4, the results obtained from the policy implementation will be further
incorporated in emissions and air quality dispersion model to identify their impact on improving
overall air quality for selected cities. These results can help in exposure assessments and to
ascertain health impacts for various groups of population, which is required to be reported in WP
7 deliverables
Ego Vehicle Localization in Dynamic Environments Using LiDAR-Based Classification of Static and Dynamic Tracks via Probabilistic Graphical Models
No full textAutonomous vehicles (AVs) are required to be able to perceive and locate their surroundings accurately in dynamic environments. Using LiDAR and odomotry data, this
dissertation proposes a novel framework for classifying tracks into static and dynamic
categories and using static tracks as reliable landmarks for ego vehicle localization. This
research is based on the principles of multi-target tracking (MTT), Growing Neural
Gas (GNG) clustering, and Dynamic Bayesian Networks (DBN), integrating advanced
algorithms such as Joint Probabilistic Data Association (JPDA) and Markov Jump
Particle Filter (MJPF). In the training phase, LiDAR and odometry data were used
to classify tracks based on relative motion patterns, resulting in an 87% classification
accuracy. During the localization process, static tracks are identified as invariant
landmarks, and dynamic tracks are excluded due to their variability. The framework
uses the classified static tracks as reference points for predicting the trajectory of ego
vehicle during the testing phase. Localization results are initially obtained based on
individual track predictions using MJPF in the testing phase. Afterwards, interaction
dictionaries are combined to perform localization under scenarios, such as simultaneous
multi-track interactions and periods with no observations and single track interaction.
Results from experiments, which validate the framework’s adaptability to real-world
autonomous navigation scenarios, demonstrate that the framework is capable of ob
taining accurate localization without external odometry updates. In this research,
reliable classification techniques are combined with an adaptable localization strategy,
advancing the development of safe and efficient AVs
Effect of sidewalk vendors on pedestrian movement characteristics: A microscopic simulation study of Addis Ababa, Ethiopia
No full textStreet vending is an essential part of the urban informal economy in developing countries. Related to rapid urbanization and socio-economic challenges, studies have proposed comprehensive street design and management that accommodate sidewalk vendors efficiently. To this end, this paper evaluated the effect of three alternatives to integrate sidewalk vendors on average pedestrian density. A social-force based pedestrian micro-simulation model (PTV-Viswalk-11) was calibrated using a macroscopic approach. A calibrated model was then used to evaluate the effect of a kiosk, a sidewalk vendor in frontage, and a sidewalk vendor in furniture zones on pedestrian movement under different scenarios. Results indicated that the average pedestrian density varied with the location and width of the vending stall, width of the walkway, pedestrian flow and the presence of a customer interacting with a vendor. The paper concludes with recommendations for planners and local authorities.Hagos, KG (corresponding author), Hasselt Univ, Dept Transportat Sci, B-3590 Diepenbeek, Belgium ; Hasselt Univ, Transportat Res Inst IMOB, B-3590 Diepenbeek, Belgium
[email protected]; [email protected]; [email protected]
Medicinal Plant Abundance in Degraded and Reforested Sites in Northwest Pakistan
No full textForest resources in northwest Pakistan are under severe threat, negatively affecting local people aiming to meet their subsistence needs through different types of forest use. In addition to uses such as fodder and fuelwood, medicinal plants play an important role in the livelihoods of local people. To reduce pressure and dependency on remaining old-growth forests, some deforested and degraded sites have been reforested. The objectives of the present study were to (1) compare the abundance of medicinal plants on reforested and formerly forested degraded land and (2) assess the influence of reforested stand characteristics on the abundance of medicinal plants. Five plots were randomly selected per land use type. On these plots we analyzed the abundance and other variables of 10 herbal medicinal plants common and important for the rural human population. Frequencies, densities, and cover of the 10 medicinal plants were significantly higher on reforested sites than on degraded sites. Frequencies of highly valuable species such as Valeriana jatamansi, Bergenia ciliata, and Paeonia emodi increased 16-, 8- and 6-fold on reforested sites, respectively. Moreover, density, cover and diversity of medicinal plants (in total) were 7, 5, and 2 times higher, respectively, and 3 species absent on degraded sites were encountered on reforested sites. On reforested plots, tree basal area was the most influential variable positively correlated with the abundance of the aforementioned species. Thus, our data suggest that reforestation of degraded sites can greatly increase the abundance of medicinal plants and may be an instrument for improving the livelihoods of local people and protecting remaining natural forest resources
Medicinal Plants and Forest Transformations in Northwest Pakistan: a preliminary synthesis
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