OpenStreetMap (OSM), the most popular VGI crowdsourcing project, is an excellent example of an open-license spatial database. But what is the quality of OSM road network datasets compared to authoritative counterparts? Several comparisons of this kind are detailed in literature but these cannot be easily adapted to other scenarios. Developing a generic automated procedure is very challenging. T...

The road coloring problem is an interesing problem proposed over 40 years ago by Adler, Goodwyn and Weiss. Hundreds of mathematicians worked on this problem and failed to make the conjecture a theorem. Finally, in 2007, it was proved by a 60-year-old Israeli mathematician, Avraham Trahtman. It turns out the prove was quite simple after Trahtman partitioned the graph into cycles and trees. The d...

We present an analytical packet/ow-level modelling approach for the performance analysis of IEEE 802.11e WLAN, where we explicitly take into account QoS di erentiation mechanisms based on minimum contention window size values and Arbitration InterFrame Space (AIFS) values, as included in the Enhanced Distributed Channel Access (EDCA) protocol of the 802.11e standard. We rst enhance the packet...

In this paper, we discuss our e ort to develop a motion estimation algorithm based on variable block size, which reduces computational complexity dramatically while maintaining good picture quality as well as high compression ratio. A key step in this work is to segment each image frame into di erent regions using a simple binary-level classi er which performs bit-wise comparison. In the second...

This paper combines terrain with the feature of road engineering to set up the constraint Delaunay triangle net in division by terrain characteristic line, and then forming range constraint Delaunay triangle net. With the data of road midcourt line, the road slope toe line and the point of intersection of road slope toe line could be calculated. Terrain characteristic line can be used to constr...

STUDY DESIGN A systematic critical literature review. OBJECTIVES To determine whether occult pathoanatomical lesions in the cervical spine of road traffic fatalities exist and if they can be identified using optimal autopsy techniques. SUMMARY OF BACKGROUND DATA Previous investigations have examined pathoanatomical conditions of the cervical spine of road traffic fatalities. However, differ...

PURPOSE The present study explored the effect of various lifestyle patterns and sleep-related factors on the sleep-related road risk. Sleep-related factors included daytime sleepiness, drowsy driving and quality/quantify of sleep. METHODS A sample of 1366 non-professional drivers aged 19-65 was selected from the broader Athens area of Greece, using stratified random sampling. The questionnair...

Good quality base and sub-base material for road pavement construction is becoming increasingly scarce. Dolerite is one of the more abundant natural road building materials in South Africa. Yet, it seems that the road design and construction fraternity shy away from using it in favour of more expensive commercially produced crushed material – and so artificially increase the scarcity of natural...