volume-03-Issue 2 (2021)
Latest Articles
A Posture Recognition System to Track Drivers’ Activities While Driving
JTTM, volume-03, Issue 2 (2021) , PP 25 - 31
Published: 21 Aug 2021
DOI: 10.5383/JTTM.03.02.004
by Khaled Shaaban, Osama Halabi, Eman Almughani from Utah Valley University, Orem, United States, 84058 and Qatar University, Doha, Qatar, 2713
Abstract: To improve traffic safety, different systems were invented to warn drivers when detecting a conflict. However, drivers may be already aware of such conflicts. In these cases, warning drivers may not effective and may lead drivers to not pay attention to warnings in the case of serious conflicts. The purpose of this study is to develop a novel posture recognition system to detect different driver activities while driving. If drivers are not braking or decelerating in the case of a conflict, they are alerted and notified about the conflict. The proposed system is based on a passive method for measuring bodypostures by using two force sensor arrays to inspect the pressure patterns exhibited in the driver’s seat and backrest. Different sensors' distributions were tested to find the most suitable distribution to improve the accuracy of the recognition. A virtual reality (VR) driving simulation was developed to test the accuracy of recognition in an immersive environment. Experiments were carried out to test the posture recognition accuracy in both realistic and VR settings. The results showed that the system could recognize different postures with high accuracy. Such a system can be used to alert drivers and disengage autonomous mode in the case of self-driving and autonomous vehicles when the situation unsafe. read more... read less...
Keywords: Sitting posture, activity recognition, driving simulator, virtual reality, autonomous vehicles
An integrated agent-based model of travel demand and package deliveries
JTTM, volume-03, Issue 2 (2021) , PP 17 - 24
Published: 18 Aug 2021
DOI: 10.5383/JTTM.03.02.003
by Anna Reiffer, Jelle Kübler , Lars Briem, Martin Kagerbauer, Peter Vortisch from Institute for Transport Studies, Karlsruhe Institute of Technology (KIT), Kaiserstr. 12, 76131 Karlsruhe, Germany
Abstract: With the increased shift from in-store shopping to e-commerce, we can expect the share of delivery vehicles in cities to rise as well. This puts great pressure on cities and surrounding areas as emissions rise and space becomes scarce. Because the last leg of the delivery chain is so costly, there have been many studies on how the last-mile issue can be diminished. However, most studies only cover deliveries independently from the orders. This paper presents a modelling approach that integrates travel demand, package orders and subsequent deliveries within the same framework. One of the benefits of the integrated modelling approach is that the model can evaluate the agents’ locations at all times during the simulation. This allows us to model different states of delivery on a microscopic level. We have applied the model to Karlsruhe, Germany with a synthetic population of just over 300.000 agents. The results show that the model simulates both package orders and the subsequent delivery tours realistically. The model framework allows for detailed analysis of delivery states and success rates and can be used for scenario analysis of different delivery methods and changes in online shopping behaviour. read more... read less...
Keywords: last-mile, agent-based, travel demand, urban freight
Measuring Vehicle Speeds, Compliance Rates, and Braking Reaction Times at Level Crossings Using Fixed and Moving Driving Simulators
JTTM, volume-03, Issue 2 (2021) , PP 09 - 16
Published: 13 Aug 2021
DOI: 10.5383/JTTM.03.02.002
by Inhi Kim , Khaled Shaaban from Kongju National University, Chungcheongnam-do, South Korea Utah Valley University, Orem, Utah, United States, 84058
Abstract: Driving simulators are used for many applications including traffic safety. There are several types of driving simulators available for researchers and engineers. This study aims to compare fixed and moving driving simulators in assessing driving behaviors at railway crossings equipped with either typical stop signs or in-vehicle audio safety system. Data used in the comparison included vehicle speed profiles, compliance rates, and braking reaction times. It was found that compliance rates were similar whereas speed profiles and breaking reaction times were slightly different. As the results of the desktop simulator had previously been compared with those from the data collected in the field, the comparison of results between the two simulators reported here can serve as a blueprint to calibrate the use of moving simulators. In summary, the different properties of the simulator can lead drivers to react to warnings differently. read more... read less...
Keywords: Braking reaction time, compliance rates, fixed driving simulator, moving driving simulator, speed profiles
Regionalization for urban air mobility application in metropolitan areas: case studies in San Francisco and New York
JTTM, volume-03, Issue 2 (2021) , PP 01 - 08
Published: 07 Aug 2021
DOI: 10.5383/JTTM.03.02.001
by Namwoo Kim, Yoonjin Yoon from Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141 Korea
Abstract: In a new era of mobility where the transportation of persons or goods via flying vehicles over urban areas has garnered great interest in its application in urban space. With the anticipated utilization of sUAS in urban airspace, a multi-dimensional understanding of urban space is essential. As a first step to assess the feasibility of Urban Air Mobility (UAM) in urban areas, we conduct regionalization and correspondence analysis in highly urbanized areas – San Francisco, CA and Manhattan, NY – by incorporating population dataset and urban 3D airspace to delineate the regional boundaries. Regionalization is carried out using graph-based clustering technique called SKATER (Spatial ‘K’luster Analysis by Tree Edge Removal) to group the regions having similar characteristics and address the compound effect of both population and spatial information. By classifying the regions into five categories through correspondence analysis, the operational and economic feasibility of each region is evaluated. The results provide the region maps of each city with the most and least attractive regions for UAM application with the temporal notion, whether the clusters are daytime-intensive or nighttime-intensive areas. The outcomes have several unique information that can benefit drone delivery target area identification, landing location identification, demand prediction. Our approach can contribute to providing a useful basis for management for UAM in urban areas as well as the process of regulating airspace use. read more... read less...
Keywords: Urban Air Mobility, UAS Traffic Management, Geodemographic Analysis, Spatial Clustering