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The paper presents traffic studies conducted by using a video capturing technique on the uninterrupted heterogeneous mix of vehicles plying on an undivided two-lane road facility. On the basis of the collected data, traffic characteristics pertaining to arrival, headway and speed distributions have been plotted considering suitable mathematical distributions to fit field observed values. The curves representing fundamental traffic flow relationships among three basic variables, namely speed, density and flow have also been established. Thus, a systematic attempt to enable the understanding of heterogeneous traffic flow parameters has been made through this exploratory study. First published online: 07 Jul 2011

Logging and sawmilling are the activities identified with B.C. and are integral parts of its economy. Forestries direct employment is about 72,000 and involves more than 6 billion dollars in economic activity. The annual log production from the coastal forest is about 31 million cubic metres. The mountainous nature of B.C.'s coast line makes the construction of continuous roads and railways difficult, if not impossible. Thus, water transport of logs is most popular way of transporting coastal logs from the logging areas to the consuming mills. There are three principal methods of moving logs on water along the coast: flat raft, bundle boom, and log barge or log ship. Each mode has its own advantages and disadvantages. Flat rafts and bundle booms do not need high initial capital investment, but because of slow speed of travel and dependency on weather condition, time taken to cover the distances are very high and sometimes unpredictable. Whereas, a log barge or a log ship requires a high capital investment, but its speed is high and is almost independent of adverse weather conditions, thus, time of travel is low. This study considers a simple problem of economic transport of logs from a single source (sorting yard) to a single destination (mill). The problem is named as a transport - inventory selection problem', which means the selection of the mode of transport from the available modes in order to minimize the sum of the yearly transportation and inventory costs. Depending on the availability of suitable data and capacities, five different modes of transport have been considered in this study. They are: flat raft, bundle boom, log barge of capacity 15,000 tons, log ships of capacities 10,000 and 15,000 tons. The study shows that different modes give minimum total costs depending on their capacities, the distance between the source and the destination, and the type of log being transported.