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Gulf of Mexico deep water oil fields present challenges to the offshore industry. Large fields require heavy drilling and production topsides which favor inshore deck installation, hook-up and commissioning in order to reduce time, costs and risks associated with carrying out such operations offshore. Harsh environments require that the motions of the structure be small to allow the use of dry trees and SCRs. A new system, called the DPS 2001, has been developed, which is a deep draft semisubmersible with a retractable heave plate. The system combines the advantages of a semisubmersible with the operational motion advantages of a truss spartype floater. Minimal motions of the DPS 2001 allow the use of dry trees with drilling/workover capability. The truss/heave plate is in a retracted configuration during fabrication and towing; this allows the deck to be stalled and commissioned inshore. The truss/heave plate is lowered and locked at a deep draft after the DPS 2001 is towed to the installation site. Because of the heave plate, the DPS 2001's motions are significantly less than that of conventional semisubmersibles and ship-type hulls. INTRODUCTION The DPS 200101 is a floating drilling and production platform designed specifically for oil and gas development in deep water harsh environments. Three different versions of the DPS 2001system are currently being developed by CSO Aker:DPS 2001-4: a fourcolumn version of the system for 8,000 - 10,000 st topsides,DPS 2001-3: a three-column version of the system for 5,000 - 8,000 st topsides, andDPS 2001-5: a five-column version of the system for use with a topsides up to 40,000 st. A patent is pending for the DPS 2001. The DPS 2001-5was presented at the 2001 DOT conference. The DPS 2001-3will be presented in the near future. The DPS 2001-4is the focus of the present paper. The DPS 2001-4is shown in Fig 1. The upper hull consists of horizontal pontoons and four corner columns and provides buoyancy. The lower hull consists of a heave plate and a truss that supports the heave plate. The heave plate provides large added mass and significantly reduces the platform's motions. The DPS 2001-4is anchored to the sea bottom with a spread mooring system consisting of chains, steel strand or polyester ropes and suction anchors. The upper hull is similar to a typical semisubmersible hull. The lower truss and heave plate unit is similar to the truss structure employed on truss spars. The system is an integration of proven components and embodies the best features of both a semisubmersible and a truss spar. The hull and the truss/heave plate unit can be fabricated in a number of yards in Asia or Europe. Upon completing the hull and truss/heave plate, it will be drytransported to the GOM. The hull and truss/heave plate will be in a retracted configuration during fabrication and transportation (Fig 2).

Fused Mesoionic Heterocycles: Synthesis of [1,2,3]Triazolo[1,5a]quinoline, [1,2,3]Triazolo[1,5-a]quinazoline, [1,2,3]Triazolo[1,5a]quinoxaline and [1,2,3]Triazolo[5,1-c]benzotriazine Derivatives.-General large-scale methods for the synthesis of the mesoionic triazoloquinolines (IV), triazoloquinazolines (XIV), triazoloquinoxalines (XIII), and triazolobenzotriazine (XV) are presented, involving the triazole ring construction via diazotization-ring closure of suitably substituted α-aminocarboxylic acid derivatives as key feature. Further functionalization of the triazoloquinoline derivatives (IV) is studied. -(ABBOTT, PHILLIP A.; BONNERT, ROGER V.; CAFFREY, MOYA V.; CAGE, PETER A.; COOKE, ANDREW J.; DONALD, DAVID K.; FURBER, MARK; HILL, STEVE; WITHNALL, JANE; Tetrahedron 58 (2002) 16, 3185-3198; Dep. Med. Chem., Astra Charnwood, Loughborough, Leicestershire LE11 5RH, UK; EN)

The development of a water tight housing with an optical quality acrylic window allows for greater range of adaptation to imposed constraints for vibration analysis underwater. Most systems for such analysis utilize tanks with windows, or fiberoptic probes requiring carefully controlled rigging and positioning methods. Use of the underwater housing gains a range of freedom from many of the barriers which can inhibit or seriously limit the aforementioned methods for underwater vibration analysis. Utilizing this unique system it was possible to instrument, rig, position, test, and do an onsight cursory evaluation of wave number frequency on a 4.0 m long×533 m diameter cylinder. A 4.5-kg maximum force shaker was installed axially on an internal bulkhead. Approximately 2.43 m of the shell was free-flooded and 1.26 m filled with lime. The shaker was situated in the cavity separating the two sections. The cylinder was suspended vertically from a rotator and centered in 10 m of fresh water. The slv was positioned at approximately 9 m from the shell allowing for a 3.3-m axial scan of the shell.