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www.sname.org/sname/mt October 2012 fraction of the total lift that is developed on the downstream portion of the body. The results indicate that indeed a larger step height will generate a larger lift-to-frictional- drag ratio. is suggests that the largest step possible should be chosen, with the upper boundary for this dimension being the height in which the ow no longer reattaches to the after body. e results show that the lift-to- frictional-drag ratio varies very little with respect to the step location over the range studied in this work. Plug-In Hybrid Direct Current Distribution for Ferry Systems, Escort Tugs, and Harbor Vessels BY VASSILI ROZINE AND JOHN OCKERMAN PUBLISHED IN THE MAY JOURNAL OF SHIP PRODUCTION AND DESIGN A new conceptual approach to the design of marine electrical distribution systems is sug- gested as an alternative to existing methods. Ferries, escort tugs, and harbor vessels hav- ing electrical distribution systems with direct current links and battery banks have prob- lems associated with necessity of fast battery recharging during short stops. e use of a modular approach to a battery design is a possible solution to these problems. e alter- native distribution systems are examined to clarify the point. Automatic Generation of Assembly Sequence for the Planning of Out?tting Processes in Shipbuilding BY YAN WEI AND UBALD NIENHUIS PUBLISHED IN THE MAY JOURNAL OF SHIP PRODUCTION AND DESIGN Outfitting processes are distinguished by interferences, disturbances, great interde- pendencies, and dierent surrounding area requirements. eir complexity is even more intensied by the use of outsourcing and sub- contracting, a broader strategy of western shipyards. Currently, execution planning of outtting processes is not suciently consid- ered. Yards play the role of director and only provide the subcontractors with a general time framework for outtting. Meanwhile, each subcontracted company plans its own progress towards its own work, independent from other executers. Consequently, outt- ting processes are delayed, frequently caused by space collision, rework, and long-time waiting on the work site. is adversely aects the execution. With the research discussed in this paper, an automatic sequence generation system, which is able to generate the inter- ference-free assembly sequences that identify the relationships among outtting activities and estimate the reasonable mounting time, has been developed. It is expected to provide each party involved in advanced outtting with holistic planning. Hence, the onsite coordination and installation eort may be reduced and the level of advance outtting practices may be increased, which leads to the reduction of cost and lead time. Statistics and Design Implications of Extreme Peak Vertical Accelerations from Slamming of Small Craft BY LEIGH MCCUE PUBLISHED IN THE AUGUST JOURNAL OF SHIP PRODUCTION AND DESIGN Inspired by Grimsley et al. (2010), this work began with an examination of the nature of slam data statistical tting. Specically, the author wished to extend Grimsleys work with an eye toward appropriate statistical distribution identication for slam responses characterized as an , ¡, or C event per Riley et al. (2010). With this information in hand, the author then returns to a discussion of the fundamental work by Fridsma (1969, 1971), Allen and Jones (1978), Jones and Allen (1972), and others to discuss the implications of nonexponentially distributed slam data on small craft design. Modeling the Dry-Docking Cost - The Case of Tankers BY AGAMEMNON APOSTOLIDIS, JOHN KOKARAKIS, AND ANDREAS MERIKAS PUBLISHED IN THE AUGUST JOURNAL OF SHIP PRODUCTION AND DESIGN Dry docking is an integral part of a vessels life. With a frequency of approximately 30 months, ag legislation and classication society rules bring the vessel to a shipyards dry dock for an intermediate or special survey. Dry dock- ing cost is a signicant element of the ships operating cost and is always presented as a six- or seven-gure amount. is paper, for the first time in the literature, unveils the determinants of dry docking cost and hence equips the decision maker with a valuable tool for the cost side of his ventures. We have collected 414 cases of ship repairs from one of the biggest ship repair yards of the Persian Gulf, over a time span of 4 years. Making use of this primary database, we develop a simultaneous equations model and express dry docking cost as a function of ship type, size, and age. Other important determinants are also incorporated into the model such as upswings or downswings in the shipping cycles and the shipping companys capacity as an eective negotiator. e method of esti- mation is Generalized Method of Moments and our results shed light on an issue that has never before been eectively dealt with, with immense practical signicance for the deci- sion maker. MTGO DEEPER Both the Journal of Ship Production and Design and the Journal of Ship Research are available by subscription. Go to www.sname.org/SNAME/Pubs/Journals1/ and ?nd out why these technical journals are indispensable to naval architects and marine engineers around the world.