Telematics data for geospatial and temporal mapping of urban mobility: New insights into travel characteristics and vehicle specific power

This paper describes a new approach for understanding urban mobility called geospatial and temporal (GeoST) mapping, which translates telematics (location) data into travel characteristics. The approach provides the speed-acceleration profile of transport flow at high spatial and temporal resolution. The speed-acceleration profiles can be converted to vehicle-specific power (VSP), which can be used to estimate vehicle emissions. The underlying data used in the model is retrieved from a large telematics dataset, which was collected from GPS-connected vehicles during their journeys over the UK's West Midlands region road network for the years 2016 and 2018. Single journey telematics data were geospatially aggregated and then distributed over GeoST-segments. In total, approximately 354,000 GeoST-segments, covering over 17,700 km of roads over 35 timeslots are parameterized. GeoST mapping of the average vehicle speed (traffic flow), and VSP over different road types are analysed. The role of road slope upon VSP is estimated for every GeoST-segment through knowledge of the elevation of the start and end points of the segments. Previously, road slope and its effect upon VSP have been typically ignored in transport and urban planning studies. A series of case studies are presented that highlight the power of the new approach over differing spatial and temporal scales. For example, results show that the total vehicle fleet moved faster by an average of 3% in 2016 compared to 2018. The studied roads at weekends are shown to be less safe, compared to weekdays, because of lower adherence to speed limits. By including road slope in VSP calculations, the annually averaged VSP results differ by +12.6%, +14.3%, and + 12.7% for motorways, primary roads, and secondary roads, respectively, when compared to calculations that ignore road slope

Air pollution and economic growth in Dubai a fast-growing Middle Eastern city

This paper discusses the impact of rapid economic development on air quality in the Emirate of Dubai, United Arab Emirates (UAE). Dubai is one of the fastest-growing cities in the world, with a population increase of approximately 80× over the last 60 years. The concentrations of five criteria air pollutants (CAPs) including carbon monoxide (CO), nitrogen dioxide (NO2), particulate matter with diameter less than 10 μm (PM10), ozone (O3) and sulphur dioxide (SO2) were studied from 2013 to 2021 at 14 regulatory monitoring stations. Results show that the biggest improvements in air pollution are for the primary air pollutants NO2 and SO2, with reductions of 54% and 93% respectively over the period studied. Gross domestic product (GDP), population growth and energy consumption are significantly and negatively correlated with NO2 and SO2 and strongly and positively correlated with PM10. CO is positively correlated with the number of buildings completed, while the results for O3 are inconclusive. Trends in NO2 and SO2 indicate that these two pollutants are decoupled from economic development, supporting, with caution, the Environmental Kuznets Curve hypothesis on the relationship between economic growth and environmental degradation. The improvement in the city's air quality is due to the effective implementation of local environmental policies, unaffected by large-scale development and urbanization. The monthly assessments of Dubai's air pollution for 2019 and 2020 show a 3–16% COVID-related improvement in the levels of the studied air pollutants, except for ozone, which increased by an average of 8%

Mapping urban mobility using vehicle telematics to understand driving behaviour

Telematics data, primarily collected from on-board vehicle devices (OBDs), has been utilised in this study to generate a thorough understanding of driving behaviour. The urban case study area is the large metropolitan region of the West Midlands, UK, but the approach is generalizable and translatable to other global urban regions. The new approach of GeoSpatial and Temporal Mapping of Urban Mobility (GeoSTMUM) is used to convert telematics data into driving metrics, including the relative time the vehicle fleet spends idling, cruising, accelerating, and decelerating. The telematics data is also used to parameterize driving volatility and aggressiveness, which are key factors within road safety, which is a global issue. Two approaches to defining aggressive driving are applied and assessed, they are vehicle jerk (the second derivative of vehicle speed), and the profile of speed versus acceleration/deceleration. The telematics-based approach has a very high spatial resolution (15–150 m) and temporal resolution (2 h), which can be used to develop more accurate driving cycles. The approach allows for the determination of road segments with the highest potential for aggressive driving and highlights where additional safety measures could beneficially be adopted. Results highlight the strong correlation between vehicle road occupancy and aggressive driving

Conjugate Effect of Joule Heating and Unsteady MHD Natural Convection in a Differentially Heated Skewed Porous Cavity Saturated by Cu-water Nanofluid

Conjugate effect of Joule heating and Lorentz force in a differentially skewed porous lid-driven cavity saturated by Cu-water nanofluid have been examined numerically. A coordinate transformation is utilized to transform the physical domain to the computational domain in an orthogonal coordinate. The Darcy-Brinkman-Forchheimer model with Boussinesq approximation is adopted and the developed mathematical model is solved by finite volume method based on SIMPLE algorithm. The influence of porous medium permeability (Darcy number), Joule heating (Eckert number), nanoparticle volume fraction, as well as inclination angle of skewed cavity on fluid flow and heat transfer characteristics are studied. The entropy generation and Bejan number also evaluated to examine thermodynamic optimization of the MHD mixed convection in porous media. The results have been presented in terms of streamlines, average Nusselt number, entropy generation, and Bejan number for a wide range of key parameters

Massline Visualization of Double-Diffusive Natural Convection inside a Cavity Filled with Nanofluid Subjected to Heat Flux and Transverse Magnetic Field

In the present work, massline visualization technique as an innovative method is utilized to deepen our insights into the problem of double-diffusive natural convection of nanofluids. The effects of inclination angle and strength of the external magnetic field on one side and heat flux coefficient on the other side on the masslines, isoconcentrations, isotherms, heat and mass transfer are fairly studied and discussed. The governing equations together with appropriate boundary conditions are solved numerically using a finite difference method in a square lid-drive cavity filled with Cu-water nanofluid. Four pertinent parameters are studied these; the orientation angle of the magnetic field (λ = 0◦ − 270◦), Hartman number (Ha = 0 − 100), heat flux coefficient (ε= 1 − 200), and nanoparticle volume fraction (ϕ = 0 − 10%). Results indicate that the orientation and strength of applied magnetic field can be considered as the key parameters in controlling double-diffusive natural convection. It is also found that the existence of metallic nanoparticles in the presence of magnetic field can play different roles in the heat and mass transfer variations. Meanwhile, high amount of heat flux injected through the cavity has an aiding effect on the convective current of mass within the cavity. Results also indicate that nanofluid has relatively smaller massline circulation loops than pure fluid

Brain, heart, and sudden death

During the past 30 years, rate of coronary artery disease (CAD), as the main cause of sudden death (SD), has decreased more than rate of SD. Likewise, cause of SD remains elusive in not a trivial portion of its victims. One possible reason is attention to only one organ, the heart, as the cause of SD. In fact, SD literature focuses more on the heart, less on the brain, and seldom on both. A change is required. In this paper, we first review the pathological findings seen in heart autopsies of SD victims after psychological stressors such as physical assault victims without internal injuries. Then, we summarize new studies investigating brain areas, like the insula, whose malfunctions and injuries are related to SD. Next, we review prototypes of neurological diseases and psychological stressors associated with SD and look at heart failure (HF)-related SD providing evidence for the brain-heart connection. Finally, we propose a new look at SD risk factors considering both brain and heart in their association with SD, and review strategies for prevention of SD from this perspective

Vehicle telematics for safer, cleaner and more sustainable urban transport:a review

Urban transport contributes more than a quarter of the global greenhouse gas emissionns that drive climate change; it also produces significant air pollution emissions. Furthermore, vehicle collisions kill and seriously injure 1.35 and 60 million people worldwide, respectively, each year. This paper reviews how vehicle telematics can contribute towards safer, cleaner and more sustainable urban transport. Collection methods are reviewed with a focus on technical challenges, including data processing, storage and privacy concerns. We review how vehicle telematics can be used to estimate transport variables, such as traffic flow speed, driving characteristics, fuel consumption and exhaustive and non-exhaustive emissions. The roles of telematics in the development of intelligent transportation systems (ITSs), optimised routing services, safer road networks and fairer insurance premia estimation are highlighted. Finally, we outline the potential for telematics to facilitate new-to-market urban mobility technologies, signalised intersections, vehicle-to-vehicle (V2V) communication networks and other internet-of-things (IoT) and internet-of-vehicles (IoV) technologies

Surgical Outcome of Very Small Intracranial Aneurysms Utilizing the Double Clip Technique

OBJECTIVES: To report the outcome of patients with very small intracranial aneurysm (VSIA) undergoing surgical clipping using a double-clip technique. METHODS: This cross-sectional study was conducted in Namazi Hospital, the main referral neurovascular center in Southern Iran during a 6-year period from September 2010 to March 2016. All patients with VSIAs ( RESULTS: Operations were performed on 32 VSIAs in 26 patients with a mean +/- SD age of 55.7 +/- 10.1 years. Middle cerebral artery was the most common location for VSIA (50.0%). There was no neck remnant, and the complete occlusion rate was 100%. The rate of intraoperative aneurysm rupture was 30.8%, and none of the patients experienced rebleeding. The 6-month mortality rate was 0% in ruptured VSIAs and 6.25% in unruptured VSIAs. Most of the patients had favorable outcomes (88.5%), and the overall mortality rate was 11.5%. The rate of permanent neurologic deficit was 10.0% in ruptured and 12.5% in unruptured VSIAs. Multivariate logistic regression analysis revealed no association between baseline and clinical characteristics and outcome in this series. CONCLUSION: VSIAs are difficult to treat because of their small sizes; therefore, with a double-clip technique, one can reduce complications related to the treatment of small aneurysms.Peer reviewe