bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of a Novel Concept for Evacuation in Dynamic Ice Conditions
Authors: Cole Tyler , Warrillow Adam , Drover Keith
Published: April 2022

With robust oil prices and a belief in the Arctic’s potential, the oil and gas industry is, once again, taking interest in the extreme northern regions. While offshore platform evacuation vehicles have been improved for open water conditions, the development of evacuation systems for ice-infested waters has lagged. This study investigated the operational requirements for evacuation vehicles in the Canadian Beaufort Sea. Following the generation of novel concepts through a series of brainstorming sessions, a three-tier vessel performance evaluation was created to rank and compare the performance of existing and novel concepts during a platform evacuation scenario. One of the novel concepts generated through this exercise is outlined in further detail.
Probabilistic Pipeline Burial Analysis for Protection against Ice Scour
Authors: King Tony , Phillips Ryan , Barrett John
Published: April 2022

A probabilistic burial analysis for protection against iceberg scouring of the seabed is presented for a hypothetical pipeline on the Grand Banks off Canada’s east coast. The analysis procedure combines a probabilistic characterization of the iceberg scour regime with a deterministic analysis of pipeline stress/strain response for a range of iceberg scour widths, depths and iceberg keel/pipeline crown clearances, allowing pipeline burial to be defined using specified stress/strain limits and target reliability levels.
Offshore Pipelines in Cold Regions - Environmental Loadings and Geotechnical Considerations
Authors: Paulin Michael J. , Kenny Shawn P. , Palmer Andrew C. , Been Ken , Caines Jonathan V.M.
Published: April 2022

With the oil industry’s continued quest for oil and gas in frontier offshore locations, several developments have taken place in regions characterized by seasonal ice cover including the US Beaufort, North Caspian, and Sakhalin Island. In these projects, pipeline transportation systems have been used, which are a cost-effective, safe and reliable mode of hydrocarbon transport to shore. One of the key design issues is ice gouging that affects engineering considerations with respect to strain based design, target burial depth requirements, cost and safety.

It is generally accepted that offshore pipelines in ice environments will need to be trenched and backfilled for protection. Burial depths can be greater than those that might normally be required for pipelines in temperate climates. Burial depth requirements will be a function of the design ice gouge depth (to prevent interaction between the ice and pipe) and an acceptable level of subgouge deformation beneath a gouging ice keel (which strains the pipeline). There still exists uncertainty on the magnitude and extent of subgouge soil deformations due to ice gouging and the importance of sediment transport mechanisms for biasing gouge statistics.

Pushing the limits to developments further offshore in deeper Arctic waters (i.e. 15 to 50m water depth) will require that additional consideration be given to aspects related to pipeline design, in particular with respect to burial for protection against ice gouging.
Canadian Arctic Shipping and Emission Assessment
Authors: Radloff Ernst , Hrebenyk Bohdan
Published: April 2022

The changing Arctic environment is a significant consideration in the forecast of future marine emissions stemming from the potential increase in natural resource extraction and inter-and intra-Arctic shipping. The Transport Development Centre (TDC) of Transport Canada has carried out a vessel emission inventory study for marine vessels operating in the Canadian Arctic. The inventory comprises a baseline assessment for the years 2002 to 2007 and forecasts to 2010, 2020, and 2050. The inventory utilizes a “bottom-up” vessel activity based approach consistent with current best practices and was completed using the marine emission inventory tool (MEIT). The forecasts were based on expected population growth, and economic activities in the Arctic. Also taken into consideration are the changes and projections for the Arctic environment, specifically when and to what extent the ice will recede allowing for increased vessel access to the Arctic.

The forecast shows that by 2050 a significant increase in Green-house gas (GHG) and emissions are expected to occur due to an increase in intra-Arctic shipping resource extraction and eco-tourism. This translates into a five-fold increase for both CO2 and NOx and significant increases in other criteria air contaminants (CAC) especially if large-scale gas production occurs in the western arctic region of Canada. The forecast also includes several scenarios such as the designation of the Arctic as an Emission Control Area (ECA) and the harmonization with EPA and IMO Marpol regulations for marine fuel and engine emission standards, which would have the potential to lower CAC emissions.
Parametric Trends of Arctic Gravity Based Structures
Authors: Spencer Paul A. , Bound Alec
Published: April 2022

Gravity Based Structures (GBS) have been used as hydrocarbon exploration or production structures in arctic regions to a water depth of about 30m and sub-arctic regions up to about 100m. The weight of the construction materials for the GBS and hence its cost depends on a large number of engineering parameters and constraints. For a particular location, the site-specific values would be used in the design. However, guidance can be obtained by performing a parametric analysis of GBS’s over a wide range of engineering requirements that may be required in future structures. We present the results of a parametric investigation into the minimum size of production GBS in ice-covered regions for the 50 to 150m water depth range and 0 to 4 million barrel product storage range. The trends in the size, cost and material construction weight of the GBS are described. In addition, aspects such as the solid ballast requirements and the floating draft of the structures are discussed. The applicability of the various designs is discussed with reference to the Chukchi, Beaufort and West Greenland Seas.
Fast Ice Drilling System – FIDS – An Improved System for Shallow Water Arctic Drilling
Authors: Shafer Randall , Noble Peter , Iyerusalimskiy Alex
Published: April 2022

The Fast Ice Drilling System (FIDS) is a concept to extend the season for Ice Island drilling and to move it into deeper water as an alternative to bottom supported drilling units, such as the Steel Drilling Caisson (SDC). As currently conceived, the FIDS can support drilling of up to four wells during the course of one winter season.

The FID System is designed to overcome one of the limitations of current ice island drilling, i.e. the requirement for shore access via an ice road. Building of ice roads can delay season start and shore leads and over-flooding in the spring can make the ice road unusable while the ice island platform is still stable and intact. The FID System is based on using marine logistics and supply which obviates (or minimizes) the need for shore access via ice roads.

The FIDS concept uses a marine vessel(s) for early construction of spray ice islands and provides support for construction of ice roads and additional man-made ice islands.

The use of logistics vessel(s) within the FIDS concept to position construction and drilling equipment, camps, fuel and other supplies in the vicinity of the target well locations improves overall efficiency and allows for an extended drilling season. This approach allows for the earliest start of ice island construction and correspondingly maximizes the time available for drilling a deep and complex well at this location.

After completion of drilling and well testing, all drilling equipment and remaining supplies on the islands are returned to the logistics vessel, which remains in the ice until break-up the following summer, when it can sail to a southern port for replenishment.

While the original FIDS study was based on the use of Russia SA-15 arctic logistics ships, it is possible to foresee construction of similar special purpose ships, perhaps with increased capacity which could support the FIDS concept and which might also act as support or wareships for te open-water drilling season in areas such as the Chukchi Sea.
The Effect of Icebreaking Bow on the Open Water Performance of a Large Arctic Ore Carrier
Authors: Yu Han C. , Kim Sungeun , Yook Rae-Hyoung , Lee Dong-Yeon , Jung Hyun-Chae , Seo Jong-Soo
Published: April 2022

The exploration of natural resources in the Arctic areas is the main drive behind recent research interest in its harsh environment. The high-quality iron ore in the Baffin Island area has attracted great interest among the mining and shipping communities. The shipboard transportation of the cargo poses numerous challenges since the vessel is required to be able to make shipments to ports in Europe year-round. The ship designer needs to keep a balance between good icebreaking performance and good seakeeping performance. The hull form of a good icebreaking bow typically requires a large flare near the waterline. However, this can cause severe wave impacts, causing increased structural loads. The hull structure is more likely to experience vibratory responses due to the increased wave impacts as the bow flare increases. This hydroelastic interaction of the hull girder in waves can cause increased bending moments and fatigue loads. This paper presents recent experimental and numerical studies of seakeeping, wave impact and hull girder responses of a large Arctic ore carrier. A series of model tests were undertaken at Samsung Ship Model Basin to investigate the global motion, hull girder loads and vibratory responses with three different bow shapes, including the icebreaking bow. A segmented model with an elastic backbone system was used to properly scale the hull girder stiffness and to simulate the vibratory responses. The effects of bow hull form on the global motion and hull girder loads were investigated. Numerical analyses were also carried out to simulate the hull girder vibratory responses in regular and irregular waves using the ABS nonlinear seakeeping program, NLOAD3D. Coupled with a nonlinear wave and slamming impact loads, it was demonstrated that the elastic beam model successfully simulates the observed hull girder vibratory responses in the time domain.
Arctic Deepwater Development Drilling Design Considerations
Authors: Kokkinis Theodore , Brinkmann Carl R. , Ding John , Fenz Daniel M.
Published: April 2022

To produce hydrocarbons economically from an arctic deepwater discovery, development drilling operations will need to drill a large number of wells over a relatively short time span, leading to a requirement for year-round operations. Such a development drilling system would operate in some of the most severe winter ice conditions occurring in the arctic seas, combining available technology elements and balancing stationkeeping capability with ice management capability. Core design considerations are outlined, involving fabrication, transportation, installation, stationkeeping and disconnection issues, and the impacts of drilling and re-supply operations are assessed. Key technical challenges and associated research and technology development needs are identified.
Multi-Year Ice Interaction with Downward Breaking Cone Structures
Authors: Fenz Daniel M. , Kokkinis Theodore , Brinkmann Carl R. , Ding Zhong
Published: April 2022

For arctic deepwater applications the use of a downward-breaking, conical-shaped hull may be required to reduce ice loads. The paper describes a test program ExxonMobil Upstream Research Company carried out in 2009 to study loads from multi-year ice on downward breaking cone structures. Tests were performed on four different cone models, covering a range of cone angles, model scales, drafts and ice drift speeds. The paper discusses observed ice failure mechanisms, the effect of draft and model scale on test results and the repeatability of ice load measurements under lab controlled conditions.
Structural Integrity Assessment for a Polar Class Arctic Tanker under Ice Loads
Authors: Dolny John , Liu Shewen , Won Dongki , Lee Jae-Yeol , Choi Joong-Hyo , Kwak Myo-Jung
Published: April 2022

The recent surge of interest in potential oil and gas reserves in the Arctic has resulted in vital technological developments in the field of Arctic shipping. New, larger vessels of novel designs are entering the region where the industry has limited experience. The design of these large vessels presents new challenges for designers and operators. ABS, DSME, and BMT Fleet have collaborated in a joint project focusing on the development of a 107,000 DWT Arctic crude oil tanker designed to comply with the IACS Polar Class PC4. Structural strength assessments of the bow and three midbody configurations subject to ice loads derived from the PC rules and several other ship-ice interaction scenarios were conducted. This paper presents the procedure and results of static nonlinear finite element analysis (FEA) and plastic grillage analysis used to simulate several identified high-risk ship-ice interaction scenarios.
Ice Navigation Curriculum using the AVTEC Ship Simulator, Seward, Alaska
Authors: Smith Orson P. , Schibel John , Hamiltion Scott , Thomas Robert
Published: April 2022

Alaska’s Arctic offshore has unprecedented attention for its prospects of mineral extraction, tourism, and new marine cargo delivery routes. The ship simulator operated by the Alaska Marine Training Center at AVTEC in Seward, Alaska, has capabilities for training ship crews for ice navigation duty, including simulation of variable ice conditions, winds, currents, and sea states. A curriculum developed by AVTEC in collaboration with the University of Alaska Anchorage, and Alaska Pilots satisfies proposed requirements of the International Convention on Standards of Training, Certification, and Watchkeeping for Seafarers, with a view toward spill prevention, emergency operations, and Arctic port design.
AURORA BOREALIS – A new European Combined Research Icebreaker and Drilling Vessel
Authors: Doelling Willy , Delius Albrecht , Lembke-Jene Lester
Published: April 2022

The paper discusses the development of the AURORA BOREALIS, a new European Polar Research and Scientific Drilling Vessel with dynamical positioning capability in drifting ice. The Vessel will be designed as a heavy icebreaker with the highest polar ice class. She will be powered to break continuously multiyear ice of more than 2.5m thickness and she will be able to manage ice ridges up to 15m height and more. She shall perform research tasks including scientific drilling missions all-year-round in the Arctic and in Antarctica without any other assisting support vessels. One of the key issues in the required performance specification for the vessel is the mandatory performance of autonomous station keeping operations in drifting level ice of more than 2.0m thickness during drilling and other research tasks.
Fatigue Damage Estimation of Hull Structure of Large Arctic LNG Carrier due to Ice Loads
Authors: Ito Hisashi , Suh Yongsuk , Jang Kibok , Park Seungmun
Published: April 2022

Fatigue damage of a large LNG carrier, Arc 4, due to ice loads is evaluated using a direct calculation method. Ice load estimation is performed based on Kurdumov-Kheisin hydro-dynamic model. Ice thickness is idealized as three categories, and independent ice operation without an icebreaker is assumed. Several hypotheses which have not been fully proven are employed as the first attempt. Fatigue damage due to ice loads is found to be negligibly small comparing with that due to wave loads.
Propulsion in Ice – Big ships
Authors: Dahler Geir , Stubbs John T. , Norhamo Lasse
Published: April 2022

A full-scale test propulsion measurement program was performed on the Fednav owned UMIAK I, a 31500 DWT bulk carrier classed by Det Norske Veritas. The propulsion machinery is distinguishable; consisting of the combination of a large-bore electronically controlled two-stroke diesel engine directly driving the large controllable pitch propeller mounted in a nozzle. The objectives of the research were to better understand the quantification of the loads caused by interaction between propeller blades and ice, and the corresponding dynamic responses through the shaft line and into the main engine, and to assess compliance with the IACS Polar Class design code.
Arctic tankers: current and future structural design practice
Authors: Tustin Robert , Niini Mikko , Ranki Erkki
Published: April 2022

Fleet development and design trends for the Arctic tanker fleet indicate a progressive increase in ship size. The trend to larger ship size is also reflected in feasibility studies considering very large Arctic tanker design concepts. A review of current Arctic tanker structural design practice is offered including an examination of two recent Arctic tanker designs to compare;

Steel-weight and benefits of two types of ice belt structures

Ice belt scantlings determined to RS ice category and IACS Polar Class rule requirements

The Arctic tanker of the future is expected to be a significant step outside of the accumulated design and operation experience base of existing Arctic tankers. For future Arctic tankers it is then expected that new practices for structural design will be required and applied.
Combined influences of aspect-ratio, dimensionless velocity, and material properties on dimensionless ice-induced pressure on structures
Authors: Arunachalam Aaruun V. M
Published: April 2022

The combined influences of aspect-radio, dimensionless-velocity and material properties of ice in estimating ice-induced pressures on structures is discussed. A large number of model test data, medium and full-scale test data, involving freshwater-ice, sea-ice, and model-ice, have been analyzed in the context of dimensional analysis and similarity concepts. Based on these analyses, dimensionless ice induced pressure (Pe/Piu2) is expressed as a function of aspect ratio (B/H), dimensionless velocity (U/Vgh) as dimensionless -material properties (17j-Vh/K/c.Influence of aspect ratio and dimensionless velocity on dimensionless ice-induced pressure is quantitatively established. Influence of dimensionless material properties on dimensionless ice induced pressure is qualitatively indicated.
Modeling of Pressured Ice Interaction with Ships
Authors: Kubat Ivana , Sayed Mohamed , Collins Anne
Published: April 2022

The paper describes numerical simulations of ship transit through ice. The simulations employ a model which is based on solving the conservation of mass and linear momentum together with constitutive equations representing plastic yield. A cohesive Mohr-Coulomb criterion with a tension cut-off is used to represent the yield condition. The numerical solution approach is based on a Lagrangian-Eulerian hybrid formulation. A depth-averaged version of the model is used, whereby the stresses and velocities are averaged over ice thickness. Ice thickness build-up and lead opening are accounted for in the model. The ice cover is driven by prescribed displacements or pressures at the boundaries. Wind and water current drag are also included. The simulations address cases of ship moving at constant velocity through a uniform ice cover, of 200 m width and 1 km length. The geometry of the Canadian Coast Guard vessel, CCGS Louis S. St- Laurent, is used in the tests. The results give the evolution of the distributions of ice concentration, thickness and pressures. The ice force-time records are also produced. The predicted forces are compared to recently reported field measurements of ice forces on the CCGS Louis S. St-Laurent. The magnitude of the simulation forces are in agreement with the measurements. A parametric study examined the role of the following variables: velocity of the ship, ice concentration, ice thickness, and properties of the ice cover (angle of internal friction). The results indicate that velocity has the most pronounced effect on ice force. The concentration and thickness also had significant effects. The angle of internal friction has somewhat less significant effects. The simulations also examined ship transit under pressured ice, or convergence, conditions. Conditions at the lateral boundaries applied ice movements against the ship during transit. The simulations show the pressure build-up against the sides of the bow due to ice convergence, and the increase in the ice force on the ship. The results indicate that ice pressures on the ship are two orders of magnitude higher than the large-scale average stresses which are calculated over a 1 km length.
Assessment of Ship Ice Loads in Pack Ice
Authors: Daley Claude , Liu Jiancheng
Published: April 2022

World trade and exploration for natural gas/oil in the Arctic/Subarctic has greatly stimulated the development of shipping in arctic regions. More and larger commercial vessels have or will operate in the harsh environments. This 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. This paper addresses such scenarios. Impacts between ships and the discrete ice floes are unavoidable. This paper develops an approach for ice load assessments for a ship interacting with discrete ice floes on the bow and midbody area. One typical scenario in those interactions in considered in this paper: a midbody impact with a second flow, following a glancing impact between the bow and a first ice floe. The 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). The paper highlights some of the challenges of direct design and hull strength checking.
Effect of Simulator Training on Novice Operators’ Abilities to Navigate in Ice
Authors: Power Stephanie M. , Power Jonathan , MacKinnon Scott , Simões Ré Antonio
Published: April 2022

Shipping and offshore industries are migrating towards operations in ice-covered waters as gateways to operating in Arctic environments. With this move, there is an increased need for equipment, procedures, and training to operate in cold, harsh environments. Currently, no training exists for lifeboat coxswains charged with navigating lifeboats in ice-covered water during emergency evacuation situations. This research study sets out to examine simulator training in comparison with traditional Standard Training, Certification and Watchkeeping (STCW) training to observe performance differences in a simulated ice field. These findings will inform manufacturers, trainers and regulators regarding the demands associated with lifeboat navigation in ice-covered waters.
Assessment of Lifeboat Laminate Strength
Authors: Gifford Peter , Kennedy Allison
Published: April 2022

The objective of this work was to assess the material strength of conventional lifeboat composites and to examine the effect that particular factors have on the strength, using design of experiments methods. The research was a direct response to the growing need for information pertaining to the performance of lifeboats in ice-covered waters. Evaluating the strength of lifeboat laminates was completed through two test programs. The first focused on assessing the tensile strength while the second examined the impact strength.
Past Experience from Arctic Commercial Expeditions
Authors: Alme Johannes , Gudmestad Ove
Published: April 2022

In the past, Norwegian vessels have entered the Arctic for fishing and for hunting whales and seals. The seal hunters needed to go to the iceedge or into the ice to catch the seals and their activity created much needed income in the past. These seal hunters came mainly from the Aalesund area of Norway (many came from the village of Brandal) and from the Tromsø area in the north.

Although seal hunting is controversial to day, there might be important learning to bring to new industries like the offshore oil and gas industry and to the navigators in ice infested northern waters. An activity within the research project “PetroArctic” at NTNU has focused on collecting experience data from the seal hunters, (Alme, 2009). A number of interviews with elders (age from 70 to 80+) have been conducted with focus on the physical environmental conditions, vessel behavior in ice and causes of loss of vessels. Among those interviewed were the legendary captain Paul Stark who sailed on sealers from 1950 to 2000 and who was involved in three vessel losses. Newspaper records from the early decades of the 20th century have been reviewed. Prior to the time of steel hull ships with diesel engines, wooden ships with sails and thereafter with steam engines were used. There were frequent losses caused by ice pressure and vessel implosions. Losses were also due to interaction with “ice foots” (Figure1) of multiyear ridges or due to hits from floating ridges on waves.

The paper presents characteristic features of vessels used and ice conditions for the different areas where seal hunting took place. These were the Newfoundland area, Labrador coast, Danish Strait, the Area in vicinity of Jan Mayen, North East Greenland coast, Spitzbergen, Eastern Barents Sea towards Novaya Zemlya and the mouth of the White Sea (Figure 2). The causes for the losses or damages to vessels are reviewed in details. In this respect it should be noted that although the ice cap might be shrinking in the future, there will be ice parts of the year over large areas. The ice might even move faster than in the past and get to new areas that traditionally have been ice free. This also relate to the ice of the polar pack that might move more than in the past. There is therefore a strong encouragement to implement the learning of the Arctic pioneers.
Thermal requirements for surviving a mass rescue incident in the Arctic: project update
Authors: Boileau Renee , DuCharme Michel B. , Cheung Stephen , Mak Lawrence
Published: April 2022

Passengers on cruise ships and aircraft traveling through the Arctic could expect to wait days for rescue, depending on weather and availability of large rescue craft. However, current standards do not specify thermal insulation for the equipment such as SOLAS* immersion suits or a Canadian Forces air-droppable survival kit that may be available to survivors. “MASSERT” is conducting a 3-year Transport Canada/SAR NIF-funded study to refine and validate long-term survival models and to recommend suitable thermal protection systems based on human experiments conducted in simulated arctic conditions in a lifeboat or air-droppable tent.
The Future of Polar Shipping Rules
Authors: Kendrick Andrew , Santos-Pedro Victor
Published: April 2022

This paper presents an overview of the current status of international and national rules and regulations of polar shipping, current activities in these areas, and the roles of some of the organizations that are involved. How regulations and standards are expected to evolve in the future is discussed and implications for ship design and project planning, construction, and the advantages of harmonized standards are outlined.
Testing of Northstar Artificial Island in Ice Model Basin
Authors: Wilkman Göran , Li Guang , Saarinen Sami
Published: April 2022

The Northstar man-made island has been on stream for some years (since 2001) already and experienced more frequent and severe storm conditions than initially expected. As a result, its armor slope protection systems required annual maintenance. To study the possibility to improve the durability of the island BP launched a testing programme to compare two different enhanced slope protection systems. In September 2008 altogether three weeks of testing in ice in various ice conditions and island configurations were performed at the Aker Arctic Technology model basin. The tests were quite complicated and time consuming. The paper discusses the test set-up, tests performed and learnings.
Pack Ice Forces on Floating Offshore Oil and Gas Exploration Systems
Authors: Liu Lei , Zhan Dexin , Spencer Don , Molyneux David
Published: April 2022

This paper presents the results of computer simulations of pack ice forces on three candidate offshore systems (which consist of a drill ship, a four legged semi-submersible platform and a six legged semisubmersible platform) using the computer code DECICE, which is a time-domain solver that uses discrete elements to model ice engineering problems. Two force components (in the plane of the waterline) and moments acting on the structure were computed for a range of ice drift velocities, ice coverage and heading angles relative to the ice drift direction. The results of the simulations give reasonable trends of ice forces and moment acting on the structures and the predicted ice flow patterns around the structure are realistic.
Mooring System for Moderate Size Arctic Vessel Terminal in Heavy Ice Conditions
Authors: Bonnaud Axel , Gudmestad Ove Tobias , Hovland Erlend
Published: April 2022

With considerable amount of oil and gas resources, the Arctic zones are becoming more and more attractive for oil and gas exploration and production. However, to be able to produce oil and gas in this region, several new challenges have to be faced. One of these is the heavy ice condition. Thus, to face this challenge, new technologies are required. In drifting ice to heavy ice conditions, a floating stationary unit must withstand the important design ice loadings. Due to these loadings, a safe design of the vessel to seabed connection, however, cannot rely on thrusters’ utilization alone. A mooring system needs to be particularly reliable and strong. Eventually, disconnection may be needed in the event of loss of position [Gudmestad et al., 09].

With regard to these observations, it seems relevant to compute and analyze the loading in the mooring device. The vessel studied in this paper is a moderately sized mono-hull icebreaker suitable as an offloading terminal for deep or shallow water production systems or onshore facilities, as control centre for subsea facilities, as process facility with a small process plant or as an intervention vessel for subsea satellites.

The Arctic Ocean has a water depth varying from tens of meters (Pechora Sea and Kara Sea as well as parts of the Beaufort Sea) to a couple of thousands meters (Canada Basin). This implies finding different mooring solutions to suit these different water depths.

Due to weight limitations, it is challenging to design a mooring system for arctic deep water made of chain or wire. The partial use of polyester ropes may be an attractive alternative. Due to its particular features, the polyester rope’s behavior is not fully understood and it is needed to be further studied for use with a moored installation in this region with very large mooring forces. This paper aims at presenting the results of ice load calculations on mooring systems composed of different kinds of mooring elements (polyester ropes, wire ropes, chains and buoyant elements) and proposing different geometries according to the water depth.
Mapping Sea Ice Overflood Along the Alaskan North Coast
Authors: Dickins David , Hearon Greg , Morris Kim
Published: April 2022

The U.S. Department of Interior, Minerals Management Service (MMS), Alaska OCS Region commissioned a study to map the extent of peak river overflooding onto the fast ice in the nearshore region of the Alaskan Beaufort Sea. River overflood constitutes a potential hazard to offshore oil and gas development, as it relates to facilities access, oil spill spreading, and the associated phenomenon of strudel drainage and potential seabed scouring. A primary goal of the study was to improve the knowledge of the spatial and temporal variability of overflooding and related hazards by mapping overflood boundaries for a 13-year period from 1995 to 2007, using a combination of helicopter surveys and satellite imagery.
ARKTOS Evacuation Craft for Beaufort Sea Shear Zone Operation
Authors: Hall T. A. , Seligman B.H.J.W.
Published: April 2022

A major area of concern for any offshore oil development beyond the Beaufort Sea transition ice region, the Shear Zone, is Escape, Evacuation and Rescue (EER) capability, due to the extreme environmental conditions that will be encountered. In response to a Shell Offshore, Inc. (Shell) initiative, a conceptual design for a 75 person ARKTOS Amphibious Evacuation Craft has been developed for operation in this region. This paper describes recent advances in ARKTOS Craft technology and new conceptual design features that have been developed for recent and future ARKTOS Craft, including the Concept Shear Zone Craft.
Arctic Sea Route Transit Analysis for Large Cargo Vessels
Authors: Choi Kyungsik , Nam Jong-Ho , Jeong Seong-Yeob
Published: April 2022

The purpose of this ice transit analysis is to determine the optimum sea routes and to estimate the operation cost, transit hour, and average speed for large cargo vessels navigating in the Arctic Sea Route prior to an actual deployment of commercial cargo vessel fleet. Four different Arctic ships, such as two bulk carriers, an LNG carrier and a crude oil tanker, are selected for Northern Sea Route transit simulation. Ice and environmental information such as sea ice thickness and concentration, wind direction and wave height are gathered and their probabilistic distribution are used to carry out a transit simulation. In an ice-covered sea, the size and distribution of sea ice significantly restrict the operation of ships and the icebreaker assistance may be an important decision for keeping the speed and direction as planned. Information of multi-year ridge formation and water depth along the Northern Sea Route are added in this analysis. After the selection of optimum sea route, total transit distances and hours, average speed, cost for icebreaker escort and total operation cost are calculated in sequence for each vessel.
Arctic Challenges - A Treatise of Past and Recent Developments
Authors: Ghoneim G. , Cammaert A. B. , Mejlænder-Larsen Morten
Published: April 2022

In view of the recent announcements by the USA government permitting further drilling in certain areas offshore Alaska and the steady increase in oil prices, it may be again possible to predict that Arctic oil and gas development and transportation projects are imminent. The challenges associated with design and operation of Arctic exploration and production installations are many and have been exhaustively discussed in the past. This paper will summarize these challenges and show how a significant number of them have been addressed in the past and how new technologies may be implemented to alleviate the remaining challenges.

In the late seventies and early eighties extensive Arctic R&D work was carried out. A small sample of this work includes the Arctic Pilot Project, the CANMAR icebreaker research program with full scale testing, the Tarsuit artificial island, the Hans island ice load monitoring programs, and the Canadian Coast Guard development of the Canadian Arctic Shipping Pollution Prevention Regulations (CASPPR). The R&D work carried out in Finland and Russia is also discussed. This paper demonstrates how the available results from these projects may be applied in the development of current and new rules and standards. The issues that are still outstanding are highlighted and proposals for possible resolution thereof are made.

A presentation of ongoing work for the development of new DNV design guidelines on ice-structure interaction will be presented. The work will be completed in 2011 or early 2012. The project will be based on the new ISO 19906 standard, and will cover both fixed and floating installations.

The paper also describes results from a recently completed real-time ice load monitoring program onboard an icebreaking vessel and shows correlation with proposed formulations.
Training Courses for Ice experts as Ice Observers and for Interpretation of Satellite Images to support Arctic Shipping Operations
Authors: Thomas Graham A.N. , Mironov Yevgeny U. , Smirnov Vladimir G. , Stepanov Valery V.
Published: April 2022

Two training courses for training ice experts were developed, arranged and delivered in a joint programme between AARI and BP. In 2007 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 in 2007 and 2008 at the Arctic and Antarctic Institute (AARI). Subsequently, practical training for two smaller groups of AARI specialists on board icebreaking vessels was completed in 2008 and 2010. In 2009, a course for training ice experts in the interpretation of satellite images of sea ice was developed and delivered to 16 trainees at AARI.
Arctic and Northern Offshore Oil Spill Probabilities
Authors: Bercha Frank G.
Published: April 2022

Current catastrophic consequences of the Gulf of Mexico blowout have refocused interest on the probabilities of such events in both temperate and northern regions. This paper reviews some of the early studies on oil spill probabilities with emphasis on oil blowouts, and details more recent studies carried out specifically for the Alaskan OCS. Due to the embryonic state of offshore oil development in arctic regions, which has been the case since 1976 to the present, it is not possible to base oil spill probability estimates on empirical data. The early studies relied on a detailed fault tree analysis dealing with the operations as systems without history. More recent studies in northern but not arctic operations use world wide data as a starting point. In the recent and current Alaskan OCS studies, statistically significant non-Arctic empirical data from the US Gulf of Mexico and world-wide sources, together with their variance, were used as a starting point. Next, both the historical non-Arctic frequency distributions and spill causal distributions were modified to reflect specific effects of the Arctic setting, and the resultant fault tree model was evaluated using Monte Carlo simulation to adequately characterize uncertainties treated as probability distribution inputs to the fault tree.
Comparison of the Effectiveness of Fernald’s Sensory Method and Educational Games on Writing Disorder in Elementary School Students
Authors: Karimi Thani Parviz , Koohzad Nasim , Ahmadi Farideh
Published: April 2022

The present study used a quasi-experimental research method with pretest-posttest research with a control group to show the effectiveness of Fernald’s multisensory method and educational games on writing disorder in elementary school students. The statistical population of this study consisted of all students with writing problems in Shabestar in the 98-99 academic year who were studying. 30 people were selected as the sample (the first 10 people in the experimental group of Fernald’s multisensory method, the second 10 people in the experimental group of educational games and the third 10 people in the control group) who were randomly selected from among students with writing difficulties in three (First experimental group, second experimental group and control group) were included. Data collection tools included Fernald’s multisensory method and educational games and the Colorado Learning Disabilities Questionnaire. Covariance analysis method was used to analyze the research hypotheses using SPSS.23 software. According to the results of analysis of covariance, Fernald’s multisensory educational method has the greatest effect on students’ writing disorder.
Biomarkers for early diagnosis and management of cardiovascular diseases
Authors: Adusumalli Ravi
Published: April 2022

In the last two decades, there has been a significant increase in interest in cardiovascular biomarkers for early diagnosis, primary disease control, and management. This has been fueled by the importation of advanced gene technology for the identification of novel biomarkers, as well as a better understanding of disease pathophysiology. This article provides a thorough examination of available biomarkers as well as their evaluation. A growing number of biomarkers are being used to assess the risk of cardiovascular disease (CVD) and to improve primary prevention. However, clinicians face a difficult task in evaluating and identifying appropriate biomarkers and when they should be used. Since the turn of the century, researchers have been examining the capabilities and limitations of novel biomarkers in the management of CVD. These studies show that much work remains to be done in order to identify novel biomarkers that are more precise and cost-effective for use in early heart disease prevention.
Index Finger Pollicization for Hypoplasia of the Thumb
Authors: Benchakroun Mohamed , Salah Rhita , Bouabid Salim
Published: April 2022

Pollicization of the index finger has been the subject of several publications; it occupies an interesting place in the restoration of the handgrip. Although it is still suffering from some technical insufficiencies, we were able to achieve a pollicization of the index finger on a 54 years old woman. The results were very satisfactory. We report in this work the surgical technique used, with an update on the various existing techniques.
The Heart was Hungrier than the Brain: Hypoglycemia-induced Ventricular Tachycardia in a Conscious Diabetic Patient
Authors: Mathur Navgeet , Mathur Medha , Verma Anjana
Published: April 2022

This case report is about a 58 years old male diabetic patient presented multiple times at outdoor (OPD) for routine follow up of diabetes always in asymptomatic, fully conscious, and oriented condition, and on multiple occasion of his OPD visit, he was found to have ventricle tachycardia (VT) on ECG with concurrent hypoglycemia (blood sugar 60 mg/dl). No antiarrhythmic treatment was needed because ventricle tachycardia subsided immediately after correction of hypoglycemia on each and every time he is having it, thus favoring hypoglycemic etiology of VT. Every time patient was having documented hypoglycemia, his heart always showed concurrent VT but the brain never showed altered consciousness or disorientation. It seems like his heart was more hungry than his brain. After an extensive search, no similar case report was found having only isolated VT at each and every episode of documented hypoglycemia. Glucose is the main fuel for the human brain. Higher mental functions were well tolerant to hypoglycemia but his heart used to respond quickly in form of VT.
Cerebellopontine angle metastatic melanoma mimicking schwannoma in a sexagenarian: Case report
Authors: Xie Hui-Min , Li Li , Richard Seidu A. , Lan Zhigang , Zhang Yuekang
Published: April 2022

Introduction: Metastasis of melanomas to the cerebellopontine angle (CPA) are very rare. Dissemination via blood, cerebrospinal fluid and/or leptomeninges may be the principal pathway for metastatic spread of malignant melanomas to the CPA. Case presentation: A 68-years old man presented with two years history of hearing lost in the right ear with associated dizziness and headaches. A skin lesion was seen on the patient’s right forearm. MRI revealed a nodular abnormal signal intensity at the right CPA which was resected and pathology revealed metastatic melanoma. Conclusion: Aggressive treatment regime comprising of a combination of surgery, chemotherapy and radiotherapy is very efficacious in prolonging the survival of patients with metastatic melanomas to the brain especially the metastasis to the CPA.
Outcome and Complications of Rectal Tube Placement in Intestinal Obstruction Due to Sigmoid Volvulus
Authors: Gholipouri Changiz , Soleimanpour Hassan , Rafraf Sahar , Gilani Neda , Gholipouri Saina , Shahsavarinia Kavous
Published: April 2022

Background: The most common site of colon volvulus is in the sigmoid colon and then in the cecum and transverse colon. The aim of this study was to evaluate the results of the rectal tube placement as an initial treatment for devaluation of sigmoid volvulus. Materials and Methods: In this cross-sectional study, 60 patients with sigmoid volvulus admitted to the emergency department of Imam Reza and Sina Teaching Hospitals due to intestinal obstruction were undergone blind rectal tube placement. After discharge, patients were followed up in two 1 month and 6 months intervals, so the rate of recovery, relapse, or mortality of the patient (in case of the patient’s death) were investigated. Results: Of the 60 patients reported, 41 patients (68.3%) were male, 54 patients (90%) the operation was successful and the patient was devaluated, but in the remaining 6 patients (10%) the operation was not successful and the patient immediately underwent an operation. The number of attempts to devaluation of patients with the rectal tube was once in 50 patients (83.3%), twice in 2 cases (3.3%) and three times in 8 cases (13.3%). The rate of hospitalization after surgery (in patients who had undergone surgery) was 6.44 ± 0.9 days. The overall rate of hospitalization in patients with sigmoid volvulus with initial treatment by rectal tube placement to devaluation was 5.78 ± 0.96 day. Conclusion: We suggested that rectal tube placement is less costly and available procedure in the treatment of patients with sigmoid volvulus.
Impact of Access Cavity Design and Root Canal Taper on Fracture Resistance of Permanent Mandibular Molars: An In-vitro Study
Authors: Niranjan Nandini T , Rajkumar Jwaalaa
Published: April 2022

Introduction: Minimal invasive endodontics in the form of conservative access designs and minimal root canal taper preparation have been devised to preserve tooth structure and increase fracture resistance. Aim: To assess the influence of two different access cavity designs and two different final preparation tapers on fracture resistance of mandibular molars. Materials and Methods: In this in-vitro study, performed over a period of two months, a total of 54 extracted human permanent mandibular first and second molar teeth with completely formed apices were selected and for infection control, the teeth were stored in 10% buffered formalin solution for two weeks before the experiment. The teeth were then randomly allocated into three groups, Group C where no tooth preparation was carried out, Group TAC in which traditional access cavity design was performed and Group TREC where Truss access cavity was performed. The groups TAC and TREC were further subdivided into subgroup A and B with two different tapers 0.04 and 0.06 taper preparations. Mesial canals of the teeth were chosen for testing the minimal root canal taper preparations. After apical gauging the distal canals, obturation and postendodontic restoration was carried out in all teeth of both the test groups. The teeth in all three groups were subjected to fracture testing in a universal testing machine. The data were recorded. Oneway Analysis of Variance (ANOVA) and Tukey Post-hoc test were used for statistical analysis. Results: The fracture resistance between group C and groups TAC and TREC and their subgroups were found to be statistically significant (p<0.05). However, there was no statistically significant difference (p>0.05) observed between the two test groups TAC and TREC and their subgroups. Conclusion: The conservative truss access design in combination with a reduced root canal taper preparation has shown to have produced better fracture resistance values in comparison to other groups and their subgroups although the results were not statistically significant.