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January 2011 www.sname.org/sname/mt A parametric study examined the role of the follow- ing variables: velocity of the ship, ice concentration, ice thickness, and properties of the ice cover (angle of internal friction). e relationships of these variables are discussed in detail, providing the reader with the magnitude of their individual eects. e simulations also examined ship transit under pressure conditions. e results of ice pressures on the ship are compared over time history, and give a practical sense of the mag- nitudes above average stress conditions. Assessment of Ship Ice Loads in Pack Ice BY C. DALEY AND J. LIU World trade and exploration for natural gas/oil in the Arctic/sub-Arctic has greatly stimulated the develop- ment of shipping in arctic regions. More and larger commercial vessels have operated or will operate in the harsh environments. is stretches the validity of the existing ship design rules and raises concerns. To deal with this challenge, owners, designers, operators, and regulators have been trying to develop more and better design scenarios. is paper addresses such scenarios, and develops an approach for ice load assessments for a ship interacting with discrete ice oes on the bow and mid-body area. One typical scenario in those interac- tions in considered in this paper: a mid-body impact with a second ow, following a glancing impact between the bow and a rst ice oe. e assessed ice loads of the two impacts within this scenario are compared to the current requirements of the hull structural strength at the bow and mid-body. From the hull strength point of view, the safe navigation speeds were estimated due to various factors (mass, velocity, geometry). e paper highlights some of the challenges of direct design and hull strength checking. Training Courses for Ice Experts as Ice Observers and for Interpretation of Satellite Images to Support Arctic Shipping Operations BY G. THOMAS, Y. MIRONOV, V. SMIRNOV, AND V. STEPANOV The continued increase in business activity in ice- covered seas makes it necessary to employ skilled ice experts to provide ice observations on platforms, at terminals, and onboard ships. Delivery of ice services in the arctic regions are real diculties related to the shortage of ice experts, considering aging of sta and the necessity to provide ice formation support to con- stantly increasing cargo trac. Two training courses for training ice experts were developed, arranged, and delivered in a joint program between the Russian Arctic and Antarctic Institute (AARI) and BP. A course for the training of ice experts?ice observers was developed, and the training of three groups of trainees (39 persons) was carried out at AARI. Subsequently, practical train- ing for two smaller groups of AARI specialists onboard icebreaking vessels was completed. A course for train- ing ice experts in the interpretation of satellite images of sea ice was developed and delivered at AARI. Details of these training courses are provided in this paper, and will help provide some of the basis for the upcoming mandates of the International Maritime Organizations polar code certication of ice navigators. From the preliminary program for the Arctic Technology Conference, to be held in Hous- ton, February 8-10, 2011 Experience of Air Bubbling Systems in Ice Navigation and Future Possibilities BY G. W. WILKMAN e air-bubbling system for use in reducing ice resis- tance of icebreaking ships was introduced in the late 1960s. After extensive development and testing, the sys- tem was used in several vessels until the early 1990s. e idea of the system is to blow compressed air down into the bilge area of the vessel hull and the expanding air bubbles will rise to the free water surface, reducing the friction between the ice and the hull surface. e paper is a summary of experience gained so far, benets of the system, and how the oil and gas industry could benet, as well ideas for new ways of using the system. Arctic Mine Sea Lift and Marine Terminal Solutions BY G. R. WATTERS This paper describes logistic sea lift arrangements and terminal design solutions for a mine project in the Canadian Arctic. Presented in this case study are sev- eral innovative design features and logistics strategies to overcome signicant obstacles for a major arctic devel- opment project. e advantages and disadvantages of using both east and west coast seaports of the United States and Canada for marshalling, staging, and load- ing of supplies are discussed. Conclusions regarding the success of the barge terminal and mooring system are described with lessons learned. MT