A redefinition of water masses in the Vietnamese upwelling area

A redefinition of characteristic water masses in the Vietnamese upwelling area is presented based on five interdisciplinary cruises during different seasons and 331 CTD casts. In contrast to the previous definition of Rojana-anawat et al. (2001), we clearly can define water masses which serve as end members of mixing. This new definition is useful for an improved understanding of geographical positions of different water masses with respect to climate variability, the phytoplankton distribution and complex nutrient cycle in this area.     

Test of extensively damaged hybrid ship hull

A hybrid ship hull model made with a steel truss and composite sandwich panels was tested and analyzed with the goal of gaining insight into how well this structural concept holds up after major damage. One of the ideas of the concept was to mount the sandwich panels to the steel truss such that they can be blown out in a controlled fashion to ventilate a large internal blast. The hull should be designed to have sufficient strength for the ship to reach a port safely even after such extensive damage. A 6-m model of such a hybrid ship hull, consisting of a stainless steel truss and 60 composite sandwich panels, was manufactured and mechanically tested. A number of panels were then removed one by one and the hull was retested to the design load after each panel had been removed. The removed panels simulated major damage. After nine panels had been removed, from all the different areas of the hull, it could still carry the design load, although with considerable nonreversible deformations of the hull girder. The hull was eventually loaded to final failure, which occurred at 25% above the design load.     

Worldscale: what does it actually measure?

Worldscale is the dominant system for setting freight rates in ocean-tanker shipping. Its structure is hampered by administrative rigidity which easily disguises the effects of rate changes and complicates the comparison of rates between vessel size segments. The angle is the charterer's, and the shipowner is left to his/her own devices. The sparseness of spot rates between ports (not regions) and the individuality of flat rates due to varying port charges, make functional generalizations between Worldscale (WS) and time charter equivalents (TCE) hazardous. The publishing of rate parameters for all ship segments and possibly port charges for each port would substantially upgrade the value of the system.