scholarly journals Efficiency Assessment of a Signalized Roundabout and a Traffic Intersection in Baghdad City

2021 ◽  
Vol 11 (6) ◽  
pp. 7910-7916
Author(s):  
H. H. Mohammed ◽  
M. Q. Ismail
Keyword(s):  
Performance Measures ◽  
Road Networks ◽  
Signalized Intersection ◽  
Movement Data ◽  
Efficiency Assessment ◽  
Traffic Intersection ◽  
Traffic Volumes ◽  
Smart Traffic ◽  
Vehicle Movement ◽  
Better Than

In Baghdad city, Iraq, the traffic volumes have rapidly grown during the last 15 years. Road networks need to reevaluate and decide if they are operating properly or not regarding the increase in the number of vehicles. Al-Jadriyah intersection (a four-leg signalized intersection) and Kamal Junblat Square (a multi-lane roundabout), which are two important intersections in Baghdad city with high traffic volumes, were selected to be reevaluated by the SIDRA package in this research. Traffic volume and vehicle movement data were abstracted from videotapes by the Smart Traffic Analyzer (STA) Software. The performance measures include delay and LOS. The analysis results by SIDRA Intersection 8.0.1 show that the performance of the roundabout is better than the signalized intersection but experiences high delay, and low LOS. Therefore, alternatives are proposed to improve the performance for current and future traffic volumes with low-medium delays.

scholarly journals Performance of Seven Consumer Sleep-Tracking Devices Compared with Polysomnography

SLEEP ◽  
2020 ◽  
Author(s):  
Evan D Chinoy ◽  
Joseph A Cuellar ◽  
Kirbie E Huwa ◽  
Jason T Jameson ◽  
Catherine H Watson ◽  
...  
Keyword(s):  
Performance Measures ◽  
Gold Standard ◽  
High Performance ◽  
Sleep Stage ◽  
Sleep Laboratory ◽  
Sleep Assessment ◽  
Sleep Condition ◽  
Different Populations ◽  
Tracking Devices ◽  
Better Than

Abstract Study Objectives Consumer sleep-tracking devices are widely used and becoming more technologically advanced, creating strong interest from researchers and clinicians for their possible use as alternatives to standard actigraphy. We therefore tested the performance of many of the latest consumer sleep-tracking devices, alongside actigraphy, versus the gold-standard sleep assessment technique, polysomnography (PSG). Methods In total, 34 healthy young adults (22 women; 28.1 ± 3.9 years, mean ± SD) were tested on three consecutive nights (including a disrupted sleep condition) in a sleep laboratory with PSG, along with actigraphy (Philips Respironics Actiwatch 2) and a subset of consumer sleep-tracking devices. Altogether, four wearable (Fatigue Science Readiband, Fitbit Alta HR, Garmin Fenix 5S, Garmin Vivosmart 3) and three non-wearable (EarlySense Live, ResMed S+, SleepScore Max) devices were tested. Sleep/wake summary and epoch-by-epoch agreement measures were compared with PSG. Results Most devices (Fatigue Science Readiband, Fitbit Alta HR, EarlySense Live, ResMed S+, SleepScore Max) performed as well as or better than actigraphy on sleep/wake performance measures, while the Garmin devices performed worse. Overall, epoch-by-epoch sensitivity was high (all ≥0.93), specificity was low-to-medium (0.18-0.54), sleep stage comparisons were mixed, and devices tended to perform worse on nights with poorer/disrupted sleep. Conclusions Consumer sleep-tracking devices exhibited high performance in detecting sleep, and most performed equivalent to (or better than) actigraphy in detecting wake. Device sleep stage assessments were inconsistent. Findings indicate that many newer sleep-tracking devices demonstrate promising performance for tracking sleep and wake. Devices should be tested in different populations and settings to further examine their wider validity and utility.

Evaluating the Operational Efficiency of Two Versions of Super Diverging Diamond Interchange Design: A Case Study in Denver, Colorado

2021 ◽  
pp. 036119812110372
Author(s):  
Muhammad Tahmidul Haq ◽  
Amirarsalan Mehrara Molan ◽  
Khaled Ksaibati
Keyword(s):  
Research Effort ◽  
Traffic Signals ◽  
Operational Efficiency ◽  
Traffic Demand ◽  
Operational Analysis ◽  
Signal Coordination ◽  
Traffic Volumes ◽  
Microsimulation Models ◽  
Better Than

This paper aims to advance the current research on the new super diverging diamond interchange (super DDI) design by evaluating the operational efficiency using real-world locations. As part of a comprehensive research effort on improving the performance of failing service interchanges in the mountain-plains region, the study identified three interchanges (Interstate 225 and Mississippi Avenue, Interstate 25 and 120th Avenue, and Interstate 25 and Hampden Avenue) at Denver, Colorado as the potential candidates to model for future retrofit. Four interchange designs (i.e., existing CDI [conventional diamond interchange], DDI, super DDI-1, and super DDI-2) were tested in this study. The operational analysis was conducted using VISSIM and Synchro. Several microsimulation models (120 scenarios with 600 runs in total) were created with three peak hours (a.m., noon, and p.m.) for existing (the year 2020) and projected (the year 2030) traffic volumes. The study considered two simulation networks: (1) when no adjacent traffic signal exists, to determine how the four interchange designs would perform if there were no adjacent signals or they were far away from the interchange; and (2) when there are two adjacent traffic signals, to evaluate the performance of the four interchanges in a bigger corridor with signal coordination needed. An important finding is that super DDI designs outperformed DDI with adjacent signals and higher traffic demand, while DDI performed similarly to or sometimes insignificantly better than super DDI if no adjacent intersections were located in the vicinity and if the demand was lower than the DDI’s capacity.

Older boards are better boards, so beware of diversity targets

2019 ◽  
Vol 26 (1) ◽  
pp. 15-28 ◽  
Author(s):  
Elizabeth Prior Jonson ◽  
Linda McGuire ◽  
Sharif Rasel ◽  
Brian Cooper
Keyword(s):  
Financial Performance ◽  
Performance Measures ◽  
Adverse Impact ◽  
Board Members ◽  
Female Representation ◽  
Industry Sector ◽  
Age Diversity ◽  
Size Firm ◽  
Primary Focus ◽  
Better Than

AbstractThis study examined 130 Australian companies from the ASX 500 All Ordinaries between 2011 and 2015. We performed regression analysis on the effects of age of the board (mean age and age diversity) upon financial performance (measured by ROA and Tobin's Q). Controlling for board size, firm size and industry sector, we found that the average age of board members is positively associated with firm performance as measured by ROA. Boards with an older average age of directors perform better than boards with a younger average age. There was no significant relationship between age diversity as measured by the within-board standard deviation on the two performance measures. The primary focus of our study was age. However, an interesting concomitant finding is that the focus on increasing female representation on boards will lower the average age of a board (as female directors tend to be significantly younger than their male counterparts) and this may have an adverse impact on financial performance.

scholarly journals Autonomous Vehicles: Vehicle Parameter Estimation Using Variational Bayes and Kinematics

2020 ◽  
Vol 10 (18) ◽  
pp. 6317 ◽  
Author(s):  
Wilfried Wöber ◽  
Georg Novotny ◽  
Lars Mehnen ◽  
Cristina Olaverri-Monreal
Keyword(s):  
Parameter Estimation ◽  
Autonomous Vehicles ◽  
Autonomous Driving ◽  
The Other ◽  
Sensor Data ◽  
Critical Feature ◽  
Motion Data ◽  
Movement Data ◽  
End Use ◽  
Vehicle Movement

On-board sensory systems in autonomous vehicles make it possible to acquire information about the vehicle itself and about its relevant surroundings. With this information the vehicle actuators are able to follow the corresponding control commands and behave accordingly. Localization is thus a critical feature in autonomous driving to define trajectories to follow and enable maneuvers. Localization approaches using sensor data are mainly based on Bayes filters. Whitebox models that are used to this end use kinematics and vehicle parameters, such as wheel radii, to interfere the vehicle’s movement. As a consequence, faulty vehicle parameters lead to poor localization results. On the other hand, blackbox models use motion data to model vehicle behavior without relying on vehicle parameters. Due to their high non-linearity, blackbox approaches outperform whitebox models but faulty behaviour such as overfitting is hardly identifiable without intensive experiments. In this paper, we extend blackbox models using kinematics, by inferring vehicle parameters and then transforming blackbox models into whitebox models. The probabilistic perspective of vehicle movement is extended using random variables representing vehicle parameters. We validated our approach, acquiring and analyzing simulated noisy movement data from mobile robots and vehicles. Results show that it is possible to estimate vehicle parameters with few kinematic assumptions.

scholarly journals Contrail study with ground-based cameras

2013 ◽  
Vol 6 (4) ◽  
pp. 7425-7472
Author(s):  
U. Schumann ◽  
R. Hempel ◽  
H. Flentje ◽  
M. Garhammer ◽  
K. Graf ◽  
...  
Keyword(s):  
Weather Prediction ◽  
Ambient Air ◽  
Lagrangian Model ◽  
Wake Vortex ◽  
The Moon ◽  
Movement Data ◽  
Different Types ◽  
Nwp Model ◽  
Better Than

Abstract. Photogrammetric methods and analysis results for contrails observed with wide-angle cameras are described. Four cameras of two different types (view angle < 90° or whole-sky imager) at the ground at various positions are used to track contrails and to derive their altitude, width, and horizontal speed. Camera models for both types are described to derive the observation angles for given image coordinates and their inverse. The models are calibrated with sightings of the Sun, the Moon and a few bright stars. The methods are applied and tested in a case study. Four persistent contrails crossing each other together with a short-lived one are observed with the cameras. Vertical and horizontal positions of the contrails are determined from the camera images to an accuracy of better than 200 m and horizontal speed to 0.2 m s−1. With this information, the aircraft causing the contrails are identified by comparison to traffic waypoint data. The observations are compared with synthetic camera pictures of contrails simulated with the contrail prediction model CoCiP, a Lagrangian model using air traffic movement data and numerical weather prediction (NWP) data as input. The results provide tests for the NWP and contrail models. The cameras show spreading and thickening contrails suggesting ice-supersaturation in the ambient air. The ice-supersaturated layer is found thicker and more humid in this case than predicted by the NWP model used. The simulated and observed contrail positions agree up to differences caused by uncertain wind data. The contrail widths, which depend on wake vortex spreading, ambient shear and turbulence, were partly wider than simulated.

scholarly journals Crime Prediction with Historical Crime and Movement Data of Potential Offenders Using a Spatio-Temporal Cokriging Method

2020 ◽  
Vol 9 (12) ◽  
pp. 732
Author(s):  
Hongjie Yu ◽  
Lin Liu ◽  
Bo Yang ◽  
Minxuan Lan
Keyword(s):  
Machine Learning ◽  
Data Fusion ◽  
Prediction Models ◽  
Crime Data ◽  
Crime Prediction ◽  
Movement Data ◽  
Environment Variables ◽  
Spatio Temporal ◽  
Fine Resolution ◽  
Better Than

Crime prediction using machine learning and data fusion assimilation has become a hot topic. Most of the models rely on historical crime data and related environment variables. The activity of potential offenders affects the crime patterns, but the data with fine resolution have not been applied in the crime prediction. The goal of this study is to test the effect of the activity of potential offenders in the crime prediction by combining this data in the prediction models and assessing the prediction accuracies. This study uses the movement data of past offenders collected in routine police stop-and-question operations to infer the movement of future offenders. The offender movement data compensates historical crime data in a Spatio-Temporal Cokriging (ST-Cokriging) model for crime prediction. The models are implemented for weekly, biweekly, and quad-weekly prediction in the XT police district of ZG city, China. Results with the incorporation of the offender movement data are consistently better than those without it. The improvement is most pronounced for the weekly model, followed by the biweekly model, and the quad-weekly model. In sum, the addition of offender movement data enhances crime prediction, especially for short periods.

scholarly journals Multi-basin and regional calibration based identification of distributed precipitation–runoff models for hourly runoff simulation: calibration and transfer of full and partial parameters

2015 ◽  
Vol 47 (2) ◽  
pp. 239-259 ◽  
Author(s):  
Teklu T. Hailegeorgis ◽  
Knut Alfredsen
Keyword(s):  
Performance Measures ◽  
Parameter Uncertainty ◽  
Weighted Average ◽  
Runoff Simulation ◽  
Temporal Validation ◽  
Simulation Based ◽  
And Performance ◽  
Hbv Model ◽  
Calibration Parameters ◽  
Better Than

Identification of distributed precipitation–runoff models for hourly runoff simulation based on transfer of full parameters (FP) and partial parameters (PP) are lacking for boreal mid-Norway. We evaluated storage–discharge relationships based model (Kirchmod), the Basic-Grid-Model (BGM) and a simplified Hydrologiska Byråns Vattenbalansavdelning (HBV) model for multi-basins (26 catchments). A regional calibration objective function, which uses all streamflow records in the region, was used to optimize local calibration parameters for each catchment and regional parameters yielding maximum regional weighted average (MRWA) performance measures (PM). Based on regional median Nash–Sutcliffe efficiency (NSE) and NSEln (for log-transformed series) for the calibration and validation periods, the Kirchmod model performed better than the others. Parsimony of the Kirchmod model provided less parameter uncertainty for the FP case but did not guarantee parameter identifiability. Tradeoffs between parsimony and performance were observed despite advantages of parsimony to reduce parameter correlations for the PP, which requires preliminary sensitivity analysis to identify which parameters to transfer. There are potential advantages of using the MRWA method for parameter transfer in space. However, temporal validation indicated marked deterioration of the PM. The tradeoffs between parameter transfers in space and time substantiate both spatial and temporal validation of the regional calibration methodology.

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