bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of TiB2 on Pressureless Sintering and Hot Pressing of ZrB2
Authors: Oliveira Davi Carolyne , Yassuda Miriam K.H. , Rocha Rosa Maria
Published: November 2016

Zirconium diboride (ZrB2) is a material of particular interest because of the excellent and unique property combination of high melting point and high electrical and thermal conductivity. In this work, the effect of TiB2 addition on pressureless sintering and hot pressing sintering of ZrB2 was investigated. Four compositions were prepared with 0, 5, 10 and 20 wt% of TiB2. First, ZrB2 and TiB2 powders were milled by planetary mill with SiC spheres at for 4 h and then they were wet mixed. Compacted samples were pressureless sintered at 2150 oC/1h and hot pressed at 1850 °C/30min with 20 MPa, both in Ar atmosphere. The added TiB2 completely dissolved into the structure and formed a solid solution with ZrB2. Addition of TiB2 in ZrB2 ceramic improved densification and hardness for both sintering process, but hot pressed samples exhibited better results.
Design and Development Philosophies for Arctic Projects
Authors: Kuehnlein Walter L.
Published: November 2016

This paper describes some design and development philosophies for Arctic Projects. In order to have success in realizing new projects in Arctic or ice covered areas, these projects need to consider besides operational and technical also social, physiological and political aspects. This means prior such a project should be defined, all aspects need be heard, collected and included in the development of the project. As we have to realize, everyone who will be not directly involved from day one in such projects might be able to stop the project at a later state resulting in a major waste of resources and money. Ambitious and challenging offshore installations in harsh environments have to be designed and optimized totally from an operational point of view taking into consideration the full range of determining factors, such as environmental sensitivity, operational aspects, technical possibilities, investment requirements, lifecycle and operational costs. Each project has to be approached with a tailor-made solution, as it is not possible to copy one project from one location to another location, even if the defining parameters are quite the same. But of course such an existing project might be a good start for developing a new tailor-made project solution.
Numerical Investigation of FRP Laminates Under Ice Loading
Authors: Quinton Bruce W. T. , Taylor Rocky S. , Veitch Brian , Kennedy Allison , Simões Ré António
Published: November 2016

This paper presents the results and insights gained from numerical simulations of the response of FRP laminate plates to ice loads. These models were motivated and supported by previous related research in the form of full-scale field trials, ice-tank model tests, and FRP laminates laboratory experimentation.

The numerical models were benchmarked against a laboratory experiment involving an actual lifeboat FRP laminate plate. Subsequently ice loads, garnered from full-scale field trials of an instrumented lifeboat in ice, were applied to the numerical laminate models using pressures, or rigid body contact.

The simulation results showed that indenter "shape" is an important parameter for laminate fracture, and that laminate layup design is critical to its resistance to fracture. A well designed laminate is far better than a thicker, poorly designed laminate.
Parallel Channel Tests During Ice Management Operations in The Arctic Ocean
Authors: Lu Wenjun , Lubbad Raed , Løset Sveinung , Skjetne Roger
Published: November 2016

During ice management operations, creating narrow parallel channels with icebreakers can effectively reduce ice floe sizes for the protected vessel/structure. Yet too narrow channel spacing requirement shall lead to excessive or even unpractical ice management operations. Empirical experience shows an almost 1:1 relationship between ‘downstream floe size’ and ‘parallel channel spacing’ while designing an ice management operation. However, before this paper, there exists no dedicated parallel channel tests with strictly controlled channel spacing and sufficient instrumentation to quantify such relationship. In this paper, we report two parallel channel tests, which have been conducted in September 2015 during an expedition to the Arctic Ocean with icebreakers, Oden and Frej. During the test, helicopter images and an onboard camera were utilised to document the parallel channel fracturing events. With the collected data, we strive to quantify if there is a prominent relationship between parallel channel spacing and the corresponding managed ice floe size. In order to analyse the floe size distribution and its relationship with channel spacing from helicopter images, we developed an image segmentation method that propagates visually identifiable seeding cracks in the image. In addition, onboard camera images were utilised to yield the frequency of parallel channel fracturing events. Given the ice conditions and Oden's specific structural form, with all the different channel spacing tested, it turned out that a channel spacing over 200 m would already prohibit the development of parallel channel fracturing events. Most of the observed events take place when the spacing is smaller than around 100 m. In addition, as was expected, more frequent fractures are taking place with narrower channel spacing, e.g., distances smaller than 30 m. The relationship between managed ice floe size and channel spacing are studied. It is found that almost all (100%) of the produced downstream floe sizes are smaller than twice the channel spacing; 90% of them are smaller than 1.5 times of the spacing; and the majority of them (from 46% to 80%, depending on the spacing distance) are smaller than 1 time of the channel spacing. With such quantified relationships, we can practically estimate the size of the managed ice floes based on known/expected channel spacing.
Ice Compression Risks to Shipping Over Canadian Arctic and Sub-Arctic Zones
Authors: Kubat Ivana , Watson David , Sayed Mohamed
Published: November 2016

The paper examines ice compression (or pressure) build-up, which may pose a threat to navigation, over various zones of the Canadian Arctic and sub-Arctic waters. The results were obtained from a multi-year program conducted at the National Research Council of Canada. The objective of that program is to quantify the risks to navigation posed by compressive ice, and to develop predictive tools to aid shipping operations in an ice environment. The work consisted of a number of activities, including: the development of an ice dynamics model tailored for high-resolution simulations of ice cover drift and deformation; creating a database of besetting events and analysis of the conditions that influence the risk of besetting; hindcasting of ice and other environmental conditions that led to besetting over various geographic regions; and the development of forecasting tools to support offshore and shipping operations and training mariners. The present paper documents the governing equations of the ice dynamics and ridging model and discusses the high-resolution implementation that makes it possible to predict the risk of vessel besetting. A case of ice compression that took place in the southern Beaufort Sea is examined. The critical values of ice pressure and ridge thickness that posed a threat to vessels during that event were found compatible with estimates corresponding to besetting events in the Gulf of St. Lawrence and Frobisher Bay.
Technical and Legislative Risks Associated With Arctic Development Case Study - Russia and Norway
Authors: Oppong Riverson , Talipova Amina , Abdul-Latif Benson Lamidi
Published: November 2016

Arctic territory, today, is one of the most prospective territories for oil and gas companies. Development of the Arctic Region completely requires new technological advancement, and thus calls for intense attention and support from experienced institutions and research centers. Following the USGC research made in 2008, more than 80% of perspective Arctic rersources are located in offshore. This inevitably conveys technical and legislative risks that are not experienced onshore or in conventional offshore fields. Technical risks are associated with severe climatic conditions, sensitive ecological situations and lack of field development experience from arctic territories, as legislative risks vary within the arctic countries in question.

This present paper consists of two main parts - analysis of technical risks, and legislative risks influence (including taxation system) on field developments in the Russian Barents Sea and Norwegian Barents Sea. In the frame of technical analysis, risk classification system according to different Arctic Sea conditions are presented. Probability for each technical risk was assessed and included in the field development project evaluation. In order to achieve synergetic effect, valuation model of field development with technical risks were then incorporated into economic model, which includes legislative restriction and taxation. These conditions differ from territory to territory; for that matter Russian and Norway.
Evidence for Movement Crushing and Recrystallization of Ice in the Keels of Scouring Icebergs
Authors: Woodworth-Lynas Chris M. T. , King Tony
Published: November 2016

When icebergs touch and scour through unconsolidated seafloor sediment the keel ice may fracture and crush, creating individual ice blocks that may rotate independently of each other under confining pressure. Blocks of ice also may be forced into and embedded in the seafloor beneath the keel. Evidence for these dynamic processes is presented based on seafloor features observed during submersible dives on the Labrador shelf in 1985 and later. Additional evidence for crushing and recrystallization of ice from the keel of a grounded iceberg is provided from thin sections of ice collected from growlers that floated to the surface after breaking free from the margin of the keel. The constant width of upslope scouring events, some traversing more than 20 m of bathymetric change on Makkovik Bank, clearly indicate that scouring keels remain relatively stable after initial crushing and modification of the keel as it first contacts the seafloor. Such stability is very likely the result of keel armouring, the action of ice protection by adhesion and freezing of coarse seafloor material into the keel. The mechanical removal of keel ice by crushing early in a scour event reduces iceberg draft so that the potential amount of drop-down of a scouring iceberg into an Excavated Drill Centre is reduced.
The Evolution of Design Tools for Arctic Subsea Pipelines
Authors: Paulin Mike , Caines Jonathan
Published: November 2016

As the demand for energy resources grew, the oil and gas industry looked north for exploration and development of offshore hydrocarbon resources. Significant discoveries were made in Arctic and sub-Arctic regions; however, these environments can be particularly unforgiving on pipelines and offshore structures with a host of geohazards unique to the area. Burial under the seabed became the common practice of protecting offshore Arctic pipelines. Innovative design considerations including installation techniques, leak detection monitoring of the pipelines during operation, and bundling pipelines together aided in the successful completion of these projects.

As design engineers on the three subsea pipelines completed in the US Arctic - Northstar (BP), Oooguruk (Pioneer), and Nikaitchuq (ENI) - all in the Beaufort Sea on the North Slope of Alaska, INTECSEA have been able to progressively improve upon design evaluations, building upon learnings from each of the previous projects.

Traditional subsea pipeline design is a stress-based approach with individual pipelines either laying on the seabed or buried to a shallow depth to protect against hazards including fishing gear or dragged anchors or for protection against upheaval buckling. In Arctic pipeline design, the extreme environmental loadings tend to require deeper burials, and due to the short installation windows and high cost of installation on-ice, may lead to the use of pipeline bundles to facilitate installation. Strain-based design is generally used for Arctic subsea pipelines due to the extreme displacement-controlled loading conditions.

This paper will discuss the evolution of the design considerations and methodologies for Arctic subsea pipelines subjected to the unique Arctic environmental loadings such as strudel scour, permafrost thaw settlement, and ice gouging. These evolving design methodologies are comprised in INTECSEA's in-house suite of Arctic Tools and pipeline design standards. Focus is also placed on the importance of appropriate environmental and geotechnical data collection, the use of limit states design, and the various trenching and backfilling aspects of pipeline design.
Burial and Exhumation History of the Labrador-Newfoundland Margin and Implications for Hydrocarbon Exploration
Authors: Japsen Peter , Green Paul F. , Bonow Johan M. , Hinchey Alana M. , Wilton Derek H. C.
Published: November 2016

The stratigraphic record along the continental margin of Labrador and Newfoundland provides ample evidence for vertical movements both prior to and after break-up. In the offshore domain, several major hiatuses punctuate the stratigraphic record. Along Labrador and the Grand Banks, Lower Cretaceous rocks rest on Paleozoic rocks or Precambrian basement in parts of the area. Onshore Labrador, the presence of a Cretaceous outlier on Precambrian basement adds to the evidence of one or more events of exhumation that has removed pre-Cretaceous sediments on a regional scale. Over much of the Labrador shelf, Miocene deposits are absent, and we show evidence based on vitrinite reflectance and sonic data that indicate that Miocene deposits of significant thickness may have been present prior to uplift and exhumation. We also present results from a pilot study comprising apatite fission-track analysis (AFTA) data that reveals a Phanerozic history involving a series of burial and exhumation episodes. The pilot study is a forerunner for a study of the onshore and offshore domain with three components. (1) A thermochronological study based on samples from outcrops and from onshore and offshore boreholes. (2) A stratigraphic landform analysis of the onshore study area based on mapping of denudation surfaces that will provide evidence of vertical motion using cross-cutting relationships between the denudation surfaces and stratigraphic constraints. (3) An integrated interpretation of the geological, geomorphological and thermochronological data to provide a coherent model of the timing and magnitude of the vertical movements along the margin both prior to and after break-up. Failure to account for greater depths of burial prior to exhumation may lead to serious underestimation of the petroleum resource maturity and to erroneous estimates of the timing of hydrocarbon generation. Uplift and exhumation may also lead to changes in migration routes and affect hydrocarbons present in reservoirs. Insights into the uplift history of a margin are important for understanding the source-to-sink system of sediment input into offshore basins.
Evaluation of Global Ice Strength for Design Iceberg Impact Loads
Authors: Fuglem Mark , Stuckey Paul , Tillson Pete
Published: November 2016

In designing an oil and gas platform for offshore arctic and subarctic regions, operators may need to consider potential iceberg impacts when determining optimal structure configuration and ice strengthening requirements. Ice strengthening requirements will depend on the frequency of impacts, the sizes and shapes of icebergs impacting, the impact velocities as determined by the response of icebergs to currents and waves and the strength of the ice. Global ice strength will influence overall design, and local ice strength will influence local structural design. Failure of ice in crushing is a complex process involving mechanisms such as spalling, pressure melting and recrystallization, which are very difficult to model. As a practical approach, global force is often modeled as the product of nominal contact area times global crushing pressure, with global crushing pressure estimated based on full scale measurements. During iceberg impacts, contact area increases with penetration, with the maximum area influenced strongly by the initial kinetic energy of the iceberg, and to a lesser extent by driving forces during the impact. Ice strength, as observed during field measurements, has a significant random variance, both in time during an interaction, and from interaction to interaction. This variance is especially important when designing for iceberg impact loads in regions such the Grand Banks off Canada's east coast where load events are very infrequent, on the order of once every 10 years given ice management. While ice strength data for sea ice loads is often presented in terms of upper limit strengths based on the assumption that there are large numbers of interactions per year, a probabilistic approach that explicitly considers the frequency of events is more appropriate.

In this paper, emphasis is given to global ice strength as relates to the total force on a structure, rather than local ice pressure as relates to local design for fixed structural areas on the platform. A strong scaling effect is observed in which the average global strength of ice decreases as the nominal area of contact increases. There is a lack of observed ice strength data for interactions involving failure of iceberg ice at large contact areas; a consequence of which is that there is not consensus in industry regarding the most appropriate strength model to use. While ISO 19906 presents a probabilistic model that accounts for variance in ice strength as contact area increases, with random coefficients to account for the variance between impacts, use of a minimum pressure cut-off for large areas is suggested due to the lack of ice strength data for large contact areas. ISO 19906 does not give guidance on the selection of the cut-off. A review of relevant data is presented here and different models for the minimum pressure cut-off considered, with example calculations presented.
Accelerating Numerical Ice Engineering Tools Using GPGPU
Authors: Alawneh Shadi , Thijssen Jan Willem , Richard Martin
Published: November 2016

C-CORE is engaged in understanding the iceberg and sea ice design loads needs of the energy sector. As the energy industry ventures into oceans with greater ice cover and more icebergs, there is a significant need for efficient engineering tools to plan and manage operations in exploration, production, and safety. Industry requires a range of scenarios for their risk assessments, where existing simulations can be computationally and time intensive.

C-CORE has recently started using the benefit of the General Purpose Computing on Graphical Processing Units (GPGPU) approach. This approach has shown significant speed up of several numerical ice engineering applications related to icebergs and sea ice. The investigated model types are Monte-Carlo type approaches for probabilistic design method, and quadratic discriminant. GPU computing with Compute Unified Device Architecture (CUDA) is a new approach to solve complex problems and transform the GPU into a massively parallel processor.

The present study applies the GPGPU technology to a Monte-Carlo simulation, used for a sea ice load application. The objective of this study is to measure the performance of the GPU using CUDA, and compare against the serial Central Processing Unit (CPU) using C++ and MATLAB implementations. Results show a speedup of up to 2,600 times of the GPGPU implementation compared to the MATLAB implementation, reducing the elapsed time from about 1.5 hour to about 2 seconds. This strongly indicates that the GPGPU approach can help the industry to significantly reduce the time required for the simulations.
Engineering in Canada's Northern Oceans – Research and Strategies for Development
Authors: Noble Peter , Jordaan Ian , Croasdale Kenneth , Frederking Robert
Published: November 2016

This paper describes the work done by the Canadian Academy of Engineering in reviewing past and current activities in Canada's Northern Oceans and in developing some ideas for strategic programs and projects to further enhance engineering knowledge and capabilities for operation in northern waters.
The Extent of Water Sheet Breakup on a Vertical Surface
Authors: Saha Debashish , Dehghani Saeed Reza , Pope Kevin , Muzychka Yuri
Published: November 2016

This paper presents an experimental investigation on the extent of water splash resulting from the collision of a flat water jet onto a vertical surface. The water sheet spread on the plate and its splash, as a result of water breakup, are the most significant phenomena that affect water delivery to marine and offshore structures. In an arctic environment, wave impact and splash can significantly affect ice accretion on a marine structure. To predict ice accretion, water sheet breakup behavior onto a surface needs to be studied closely. The motivation of this experimental study is to further examine water sheet splash. The tests performed in the lab scale setup comprise of high-speed image capture from a water jet-vertical surface collision at various attack angles, which cause mild to severe breakup situations. The results show that variation in jet velocity significantly affects the height, width and splash area of a water sheet. The results also show that attack angle is another significant factor for water trajectory and therefore water shedding beyond the vertical surface. The interdependence in between water trajectory and water shedding provides a new correlation of water transport after water sheet breakup.
Modelling the Ballistics and Thermodynamics of Bow Spray Droplets for Marine Icing
Authors: Hoes Carlet M. , Aalbers Albert B. , Hoving Jeroen S.
Published: November 2016

In preparation to the SALTO JIP (Safe Arctic Logistics, Transport & Operations) work was done towards developing an improved model for icing due to sea spray at the bow of a ship. The so-called SHIPICE model may be used in a probabilistic risk-based approach and consists of two main segments: Probabilistic modeling of spray water volumes and the break-up in droplets rising above the freeboard, andModeling the ballistic and thermodynamic processes of these droplets when falling and freezing to the ship.

The present paper deals with the second phase of the SHIPICE model. The modeling of marine spray shows that spray is a phenomenon with sharply increasing volumes with speed and sea state. Furthermore, the droplet size of spray rising above the freeboard has a distinctive effect on the distribution of the spray volume landing on deck. The thermodynamic freezing model takes into account intermittent wetting and run-off, and depends also on the droplet size distribution due to in-flight cooling of the droplets when falling to the ship. The results from the model seem realistic when computed icing growth is compared with two measured icing events reported in literature. The development of SHIPICE will allow users to dimension pre-cautions to the area and time of operation. Additionally, it will provide an improved basis for regulations and guidelines (e.g. ISO TC 67 SC8). For ship owners, it will help evaluate the susceptibility of their ship to marine spray icing.
Infrared Image Analysis for Estimation of Ice Load on Structures
Authors: Fazelpour Azam , Dehghani Saeed R. , Masek Vlastimil , Muzychka Yuri S.
Published: November 2016

An analysis using infrared and visual images is made to measure the ice thickness of a cylindrical component. The proposed method is useful for ice detection and measurement on structures, even in harsh conditions and low light situations such as night. This type of analysis can fill a gap of knowledge related to ice measurement using both visual and thermal images. Thermal imaging shows differences in the emissivity and temperature of objects. This can help to detect objects and measure the amount of ice accumulated on the objects. Combining the information of visual and thermal images can compensate for their weak points and present better results. Combinations of the color-visual image (CVI), grayscale-visual image (GVI), color-infrared image (CII) and grayscale-infrared image (GII) are used to find the most accurate results. A binary image is acquired using the threshold method based on data collected from infrared and visual images. Using threshold levels removes irrelevant data that come from the background. Common ice pixels detected from both infrared and visual images are considered as the ice area. Thresholding methods cause unwanted gaps and strips in binary images. Morphological algorithms are used to remove these imperfections. The best results are obtained when one of the elements of the combinations is CII. The results of using CVI and GVI are almost the same. The experiments show that this method is reliable and its results are aligned with the real data.
A Joint Industry Programme to Improve Oil Spill Response in the Arctic
Authors: Mullin Joseph V.
Published: November 2016

Results from hundreds of studies, laboratory and basin experiments and field trials conducted worldwide over the past 50 years, in particular in the United States, Canada and Scandinavia, show that the industry has a wide range of viable technologies, beyond mechanical recovery, for oil spill response in the presence of ice in open water. To continue to build on this existing research and improve the technologies and methodologies for Arctic oil spill response, nine international oil and gas companies (BP, Chevron, ConocoPhillips, Eni, ExxonMobil, North Caspian Operating Company, Shell, Statoil, and Total) are working collaboratively in the Arctic Oil Spill Response Technology - Joint Industry Programme (JIP).

The JIP has brought together the world’s foremost experts on oil spill response research, development, and operations from across industry, academia, and independent research centres to undertake the technical work and scientific studies. The core areas of research are: dispersants, environmental effects, trajectory modelling, remote sensing, mechanical recovery, and in situ burning (ISB) in Arctic and ice-prone regions. Significant work is committed to developing a robust information database that will support the use of Net Environmental Benefit Analysis for response decision-making and environmental impact assessments related to the Arctic environment.

Phase one of the JIP is complete and seventeen research reports dedicated to literature and state-of-theart reviews are available on the JIP website (www.arcticresponsetechnology.org). This initial phase identified specifically targeted research projects to improve industry capabilities and coordination in the area of Arctic oil spill response. Phase two activities actively underway include dispersant effectiveness testing; modelling the fate of dispersed oil in ice; assessing the environmental effects of an Arctic oil spill; advancing oil spill trajectory modelling capabilities in ice; extending the capability to detect and map oil in darkness, low visibility, in and under ice; and expanding the ‘window of opportunity’ for ISB response operations. The JIP is committed to sharing information with the public on the progress and results of its projects with the objective of improving Arctic spill response capabilities.
Oil Spill Response Options in the Outer Continental Shelf
Authors: Bruce Harland , Mitchell Vince
Published: November 2016

Description of the Paper: Our paper outlines the history of spill response requirements in the U.S. Arctic and how incidents have shaped spill legislation. A review of the equipment utilized in spill response from the 1980’s and focuses on the exploration efforts in the Beaufort and Chukchi Seas. It also covers a review of the changing spill response requirements and their impact on the Shell exploration effort.

The experiments and real life experience with spills in ice are reviewed and the equipment and tactics developed from this experience will be described. The limitations of each recovery option are explored and when each tactic would be effective in a spill event.

Proposed spill response platforms for effective spill response operations are identified and how spill response equipment can be deployed in the field.

Application: Spill response options are shown for working in the Arctic in the various ice conditions that may be experienced throughout the year.

Results, Observations and Conclusions: The paper covers the changes in response equipment designed to operate in the Arctic and the tactics that are effective as well as touch on future research that is needed to improve recovery options.

Significance of Subject Matter: The effectiveness of a spill mitigation plan is critical in securing the permits and social license to explore for hydrocarbons in the fragile Arctic environment.
Design of a Multibody Dynamics Based Model Scale Test for Towing Operations in Managed Sea Ice
Authors: Lu Wenjun , Samardzija Ilija , Lubbad Raed , Sukhorukov Sergiy , Hagen Dagfinn , Rognaas Gunnar , Østlund Hilde Benedikte
Published: November 2016

With a series of physical model tests performed during February to August 2016, Arctic towing operation was investigated while towing a Gravity Base Structure (GBS) in managed sea ice with varying parameters: ice concentration, floe size, towing speed and towing configuration. The CONDRILL™ Arctic driller (Gravity Base Concrete structure) is a promising structural concept for extended exploration drilling operations in limited open water season and in harsh ice conditions. In the studies, the model-scale Arctic driller concept were constructed and tested in different paraffin-made model ice conditions. The tests, designed to shed light on both the physics and the practicalities of moving the GBS in varying ice conditions where towing force and structural stability, influenced by ice resistance are central for a successful platform design. The current model test is the first in a series where the results will be used as design input as well as subsequent marine operations employed for moving the platform in managed sea ice. This paper discusses initial assessments of towing force under varying ice conditions through physically modelling the most significant ice load contributor (i.e., the ice accumulation and clearing process). Based on the model tests, an optimum towing configuration, which involves no permanent ice jamming in all the tested ice conditions, was identified. In addition, it was found that for ice concentrations lower than 60%, the towing speed (or hydrodynamics) governs the towing resistance and the influence from ice floes are minor. However, while at high ice concentration (e.g., ≥70 - 75%), we are shifting from a hydrodynamics governed scenario into multibody dynamic interaction governed scenarios, in which, ice accumulation/clearing and internal friction resistance between the ice floes dominate the tow resistance. The study highlights the importance of an efficient ice clearing mechanism to release the pressure built-up in front of the structure and transport broken ice to the wake region of the structure, which results in lower resistance during towing. The studies reported in this paper contribute to the following items: 1) The multibody dynamic based physical modelling test would be the first of its kind to isolate this important physical process and to study it thoroughly without the influence from other physical processes such as sea ice fractures. 2) The test results are useful to validate currently available numerical simulation tools based on Discrete Element Method (DEM).
How to Unlock the North East Greenland Offshore Reservoirs
Authors: Anink Wouter , Jong de Douwe , Wassink Alain
Published: November 2016

The hydrocarbon reservoirs offshore North East Greenland are found in one of the most challenging environments in the world. Rigs will have to cope with, amongst others, short to non-existent open water seasons and large amounts of multi-year ice transported directly down from the North Pole, causing year around multi-year ice presence in the area.

Several potential solutions for unlocking these reservoirs are being discussed, ranging from dedicated arctic rigs, to winterized and ice classed open water rigs.

The paper will present an evaluation of four different rig designs comprising a turret moored arctic drillship, two winterized and ice classed open water drill ships and a winterized and ice classed drilling semi-submersible. The evaluation will address both the requirements to drilling operations offshore North East Greenland as well as the resulting capabilities for each rig design. In addition off-season usage possibilities will be addressed as part of the evaluation.

The winterization and ice class requirements for the open water rig designs will be specified in a way which allows the rigs to operate offshore North East Greenland during the summer season. Capabilities of all designs will be determined on the basis of in house and publically available ice-load data. The consequential operability offshore North East Greenland will be determined on the basis of available ice data allowing for a comparison of the operational window lengths for the different units.

As it is unlikely that any of the designs will be able to operate year around offshore North East Greenland in an economically attractive way, off-season usage possibilities will be evaluated as well, considering relevant areas in or near the Atlantic basin.

The results of the offshore North East Greenland evaluation will be combined with the off-season usage possibilities in an overall comparison of the four rig designs.

As a final result the paper will present a rationalized comparison between several potential solutions to unlock the hydrocarbon reservoirs offshore North East Greenland. As a consequence the paper eliminates to a large extent the subjective part in the design selection process for this specific application. Thus providing a valuable overview that has been missing until now.
Empirical Prediction of Sea Ice Surface Temperature from Surface Meteorological Parameters in Pistolet Bay Northern Newfoundland
Authors: Turnbull Ian D. , Taylor Rocky S. , Bailey-Dudley Eleanor , Pritchett Robert , Crocker Greg
Published: November 2016

Thermodynamic models of sea ice are important tools for the prediction of the patterns of the seasonal evolution of regional ice concentration, thickness, as well as the flexural and compressive strength of the ice. These models aid in offshore operational planning, decision-making, and structural design in the sectors of marine transport and hydrocarbon development in ice-prone environments. The initialization of vertical ice temperature profiles and the definition of boundary conditions for temperature at the ice surface and base have a significant impact on the evolution of internal ice temperatures in these models and the associated melt, growth, and strength response of the ice. While the ice basal temperature in thermodynamic models is relatively straightforward to define as the freezing temperature of seawater, the ice surface temperature is less certain and is traditionally estimated using a surface energy flux balance. During February 27-29, 2016, six Temperature Acquisition Cables (TACs) and two data loggers were installed on the snow-free land-fast sea ice in Pistolet Bay, northern Newfoundland in Atlantic Canada. The TACs and data loggers recorded vertical ice temperature profiles and surface air temperatures at five-minute intervals. Two co-located tripod-mounted anemometers recorded oneminute surface wind speeds. Dew point temperatures and cloud areal fraction were obtained from the European Centre for Medium-Range Weather Forecasts (ECMWF) ERA-Interim Reanalysis, and downwelling longwave radiation was inferred from the surface air temperature measurements and cloud cover data. Incoming shortwave radiation was also calculated. In this paper, an alternative robust and more computationally efficient method is presented for solving the ice surface temperature as a linear function of the aforementioned surface meteorological parameters. Subsequently, the linear model is used to establish ice surface temperature boundary conditions in order to demonstrate its use in modeling the evolution of the vertical ice temperature profile as recorded by one of the TACs.
InSAR Monitoring of Alaska Highway Instability in Permafrost Regions Near Beaver Creek, Yukon
Authors: Chen Zhaohua , English Jerry , Adlakha Paul
Published: November 2016

Thaw subsidence can damage the infrastructure including buildings, roads and airfields founded on ice- rich permafrost, increase their maintenance costs, change the landscape and influence the sustainable development in the northern region. Information about the ground movements is important for making decisions on various geotechnical approaches to reduce impacts of permafrost degradation. However, field measurements of ground movements and long term monitoring using traditional field survey may be logistically expensive in vast and remote Northern Canada and Alaska, USA. The ability to measure surface displacements, identify the areas being impacted, and provide information of seasonal timing using remote sensing techniques would improve the knowledge and expertise of those involved in infrastructure engineering and management where permafrost is degrading. Traditional Interferometric Synthetic Aperture Radar (InSAR) measurements of deformation do not consider the effects of seasonal freeze-thaw, thus may not effectively reveal the long term trend of ground movements in permafrost region. In this paper we propose to quantitatively evaluate the seasonal ground movements resulted from on-going seasonal freezing and thawing, and estimate long term deformation of linear infrastructure in permafrost area using InSAR technique. The proposed approach has been tested on Alaska Highway built on permafrost at Beaver Creek, Yukon, Canada using Radarsat 2 data acquired during 2013-2015. Results indicate that there was long term deformation at a rate of five cm/year, in addition to an average of magnitude of vertical movement of 4 cm between winter heaving and summer thawing during annual climate cycles.
Effect of Rudder Force on Stern Shoulder Region Ice Loads
Authors: Valtonen Ville
Published: November 2016

In this paper, the relationship between the rudder lift force and ice loads on the stern shoulder of a vessel hull is studied. The study is based on full-scale measurements with research vessel SA Agulhas II on Antarctic voyage 2012-2013. The results show that rudder lift force has a significant effect on the ice loads on the stern shoulder region.
Deepwater Newfoundland and Labrador: Technology Application and Opportunities for Exploration and Production
Authors: Brown Murray , Power Desmond , King Tony , McAffee Rodney , Dodge Kelley
Published: November 2016

There has been considerable interest in deepwater opportunities offshore Newfoundland and Labrador (NL). The significant discovery of Mizzen, Harpoon and Bay du Nord fields by Statoil and partner Husky Energy, as well as the regional seismic data and metocean characterization projects by Nalcor, has generated industry interest in the area resulting in successful calls for bids in the deepwater region by the Canada Newfoundland Offshore Petroleum Board (CNLOPB) in 2014 and 2015. With the recent exploration license activity and significant deepwater discovery, the potential for further exploration and near-term development is rapidly approaching. There has been extensive operations experience and research and development within the shallow waters of continental shelf Jeanne d'Arc Basin over the past 40 years. With the progression of opportunities for exploration and development in deep water, the operations experience and applied research proven in shallow water can be utilized and adopted to deep water. The technical aspects of Remote Sensing, Ice Engineering, Ice Management and Geotechnical Engineering will be reviewed and discussed in the context of deepwater developments and opportunities for enhancement of technology will be presented.
Ice Drift in the Beaufort Sea from Tracking Beacons, Winter 2009-2010
Authors: McGonigal David , Hill Michael C. , Guzman Leonardo , Hagen Douglas
Published: November 2016

In the winter of 2009-2010, seven ice tracking beacons were deployed in two separate arrays in the ExxonMobil/Imperial Oil lease known as Ajurak in the Canadian sector of the Beaufort Sea. The Ajurak lease lies 100 to 160 km north of the Mackenzie Delta, in water depths ranging from 60 m to 600 m. The purpose of the deployment was to assess the fate of a hypothetical under-ice well blow-out. The purpose of this paper is to describe the planning process prior to field operations including a Health, Safety and Environmental (HSE) plan and a Safe Operations Plan (SOP), the deployment, the data analysis and the resulting drift tracks and velocity statistics. Satellite imagery was used to monitor ice conditions prior to deployment to assess the competence of the ice cover, and also to chart the development of land fast ice throughout the winter. An array of beacons deployed in early December followed the expected pattern of westerly drift with periods of rapid drift and occasional reversals and stationary periods. The leading beacon passed Point Barrow, 750 km west of Ajurak, in 4 months. By July, this beacon had drifted well into the Chukchi Sea, a total of 1370 km from its deployment location. The second array of beacons, deployed in mid-January, remained within the Canadian Beaufort Sea.

The longest surviving beacon in this array drifted about 200 km west of Ajurak and stopped reporting in late April. Drift of this array appeared to be impeded by the development of large seaward extensions in the land fast ice adjacent to the Alaskan coast, as well as a series of onshore movements of the polar pack ice.
Underwater Noise of an Azipod® Propulsion Unit with Heavy Ice Class
Authors: Veikonheimo T. , Roivainen J. , Huttunen T.
Published: November 2016

Acoustically the submerged components of an Azipod propulsion unit comprise two uncorrelated noise sources, namely the propeller and the electrial motor. The propeller hydrodynamic noise is highly dependent on the load & speed whereas the magnetic noise of the electric motor exhibits a smoother dependency on the load & speed. The electromagnetic noise of the motor is highly dependent on the converter supply properties such as the number of voltage levels and current/voltage modulation parameters.

The paper deals with the challenge of estimating the total underwater sound emission of an Azipod unit using both the airborne sound power measurements and underwater sound emission simulations and current hydrodynamical tools available.

The airborne electromagnetic noise emission of the unit can be measured at a factory testbed using the designed converter supply together with correct shaft loading. Sound intensity based methods are favoured in the paper due to their ability to exclude the extraneous noise from the results (factory background noise & noise from the loading machine). Once the airborne noise figures are obtained, a conversion to corresponding underwater noise figures is needed. This is accomplished by computing the airborne and underwater noise radiation with same electromagnetic loading using FE-method for the structural dynamics and BEM for the acoustic radiation. The conversion factor K from airborne to waterborne sound emission is finally obtained for each of the electomagnetic excitation patterns. The accuracy or goodness of K is then validated by comparing future underwater noise measurements during sea-trials and the measured airborne emission at the test floor.

Separate analysis of hydrodynamic acoustic characteristics are performed with three different tools and finally combined to total URN level with electromagnetic noise emission estimation.

In this work, the underwater fluid loading on the Azipod unit surface plates is included by using a very simple approach, which is to be addressed in future studies.
Efficacy of EMG/bioimpedance-triggered functional electrical stimulation on swallowing performance
Authors: Schultheiss Corinna , Schauer Thomas , Nahrstaedt Holger , Seidl Rainer O. , Bieler Jehoschua
Published: November 2016

In order to support swallowing, the efficacy of functional electrical stimulation for different stimulation settings of the submental musculature has been investigated. The stimulation was administrated at rest and synchronously to voluntary initiated swallows. The onset of a swallow was detected in real-time by a combined electromyography/ bioimpedance measurement at the neck in order to trigger the stimulation. The amplitude and speed of larynx elevation caused by the FES has been assessed by the observed change in bioimpedance whereas a reduction of bioimpedance corresponds to an increase in larynx elevation. Study results from 40 healthy subjects revealed that 73% of the subjects achieved a larger and faster larynx elevation during swallowing with triggered FES and therefor a better protection of their airways. However, we also observed a decrease in larynx elevation compared to normal swallowing in 11 out of the 40 subjects what might not benefit from such a treatment. The largest improvement of larynx elevation and speed during swallowing could be achieved with three stimulation channels formed by four electrodes in the submental region.
Stem cells and tissue niche: two faces of the same coin of muscle regeneration
Authors: Scicchitano Bianca Maria , Sica Gigliola , Musarò Antonio
Published: November 2016

Capacity of adult muscle to regenerate in response to injury stimuli represents an important homeostatic process. Regeneration is a highly coordinated program that partially recapitulates the embryonic developmental program. However, muscle regeneration is severely compromised in several pathological conditions. It is likely that the restricted tissue repair program under pathological conditions is due to either progressive loss of stem cell populations or to missing signals that limit the damaged tissues to efficiently activate a regenerative program. It is therefore plausible that loss of control over these cell fates might lead to a pathological cell transdifferentiation, limiting the ability of a pathological muscle to sustain an efficient regenerative process. The critical role of microenvironment on stem cells activity and muscle regeneration is discussed.
Human-FES cooperative control for wrist movement: a preliminary study
Authors: Gui Kai , Yokoi Hiroshi , Zhang Dingguo
Published: November 2016

Functional electrical stimulation (FES) sometimes applies to patients with partial paralysis, so human voluntary control and FES control both exist. Our study aims to build a cooperative controller to achieve human-FES cooperation. This cooperative controller is formed by a classical FES controller and an impedance controller. The FES controller consists of a back propagation (BP) neural network-based feedforward controller and a PID-based feedback controller. The function of impedance controller is to convert volitional force/torque, which is estimated from a three-stage filter based on EMG, into additional angle. The additional angle can reduce the FES intensity in our cooperative controller, comparing to that in classical FES controller. Some assessment experiments are designed to test the performance of the cooperative controller.
Soft Encapsulation of Flexible Electrical Stimulation Implant: Challenges and Innovations
Authors: Debelle Adrien , Hermans Laura , Bosquet Maxime , Dehaeck Sam , Lonys Laurent , Scheid Benoit , Nonclercq Antoine , Vanhoestenberghe Anne
Published: November 2016

In this document we discuss the main challenges encountered when producing flexible electrical stimulation implants, and present our approach to solving them for prototype production. We include a study of the optimization of the flexible PCB design, the selection of additive manufacturing materials for the mold, and the chemical compatibility of the different materials. Our approach was tested on a flexible gastro-stimulator as part of the ENDOGES research program.