Ministry of Transport and Communications

Average delays are an example of traffic network performance measures. They can be measured at intersections to estimate the average delay per vehicle at various levels, such as intersection, approach, or lane group. On the other hand, average delays at a given route are implicitly measured by estimating the difference between free-flow travel time to the observed ones. Different methods are used to estimate travel time for a given route, such as floating car, average speed, and vehicle tracking methods. This paper focuses on developing an artificial neural networks (ANN) model to predict travel time for specific routes based on field travel time measurements and other easy to measure characteristics, that are related to geometric layouts, peak-hour periods, posted speed limits, and route lengths. Travel time data for 75 different segments located in the State of Qatar were studied. Directional travel time data were measured in three different peak periods. A total of 450 travel time values were collected and analyzed. An ANN model was trained to estimate travel time. The results show that the ANN model was able to provide a reasonable estimation of travel time using limited information. The slopes of the regression plots between observed and predicted travel time values show a clear linear trend, with slopes around 0.85, and an intercept that is around 2.0.

Delay at signalized intersections can be estimated by performing onsite measurements, applying analytical models, or using microsimulations. The Highway Capacity Manual 2010 (HCM 2010) methodology is considered to be one of the most convenient and practical analytical methods. HCM 2010 includes a set of different performance measures that thoroughly describe the operations for various travel modes, which makes it the favored methodology by local traffic engineers and planners. This study uses observed traffic data at major signalized intersections to estimate and compare different methods of estimating traffic delays at those intersections. A total of 16 intersections located within the City of Doha in Qatar are selected. For each intersection, traffic demand and signal timings data are collected during three peak periods. First, the turning movements, queue lengths, and geometric layout data are used to build these intersections within a microsimulation environment. To replicate real-life conditions, the microsimulation models were calibrated using several measurements that are observed in the field, such as average delay, average travel time, and intersection throughputs. The HCM2010 procedures are then used to estimate the delays at those junctions. A comparison is made between the simulated delays and those estimated using HCM 2010 procedures. The results revealed that the HCM 2010 method overestimates the calculated control delay at signalized intersections. Moreover, the results show that the default base saturation flow rate of 1,900 pc/hr/ln does not reflect the local conditions in the State of Qatar. Further investigations reveal that a base saturation flow rate of 2,300pc/hr/ln is better reflecting the real-life traffic conditions in Qatar.

The main objective of this study is to investigate the status of traffic safety and the public perception of traffic safety during the during COVID-19 pandemic. Three different data sets are used in this study: road crash and traffic violation data from Qatar, and two separate questionnaire surveys (from general public and road safety experts). Results showed that during COVID-19 period, the total number of crashes in Qatar significantly reduced during the pandemic compared with the previous 5 years. However, the rates of serious and fatal injuries significantly increased. Regarding the general public perceptions, more than 80% reported that roads became safer while driving behaviours improved during the pandemic. On the other hand, more than 50% of the experts disagreed that roads became safer, 55% disagreed that driving behaviours improved and 70% agreed that less attention from governments was directed toward road safety during the pandemic. The findings from this study could help policy makers to understand the road safety status during the pandemic to make appropriate adjustments in the traffic laws and regulations on a temporary basis. This could help in reducing crash-related injuries and as a result reduce pressure on health and other emergency services.

Vor dem Hintergrund der aktuellen politischen Lage in Deutschland, die in hohem Mase von der „Herausforderung Linkspartei“ gepragt wird, bietet der Beitrag eine Darstellung verschiedener Kommunikationsstrategien. Dabei macht der Autor sehr deutlich, dass ein Paradigmenwechsel in der politischen Kommunikation ebenso notig ist, wie in der Politik selbst.

The total length of the Finnish minor road network is about 345 000 km (214,373 mi). The Finnish National Road Administration is responsible for some 65 000 km (40,389 mi) of minor roads, which are called public roads. The remaining 280 000 km (173,984 mi) are private roads that are constructed and maintained mainly by property owners who usually form cooperative societies that take care of this in practice. The role of raw wood haulage is significant, representing about three-fourths of the transported tons if mainly short-distance gravel transportation is excluded. Annual rehabilitation and maintenance funding needs were estimated to be at the level of 750 million to 800 million FIM by using a network management system. The available funds should be allocated to locations where improvements lead to the widest possible positive effects for freight transportation and settlement. For freight transportation this means that frost-damaged road sections should be eliminated from locations that have the widest effects on the utilization of wood resources. To promote development in rural communities funds should be allocated for access roads to communities where other prerequisites for development also exist. The interface between public and private roads needs to be reassessed. The concept of private roads is a very inexpensive and effective way of maintaining low-volume roads.