bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ridge Keel Forces on Vertical Structures
Authors: Charlebois L. , Frederking R. , Sayed M. , Barker A. 
Published: November 2016

Abstract
In northern regions, ice forces, or actions, must be considered in the design of structures such as light piers, bridge piers, and offshore platforms. Estimates of ice forces in Canadian waters are usually obtained by consulting design standards such as those developed by the International Organization for Standardization (ISO) and the Canadian Standards Association (CSA). These design standards draw on available analytical formulae. Field measurements are available from several sources that suggest reasonable agreement with analytical results for simple cases involving wide structures.
One of the remaining uncertainties in estimating design loads, however, is the contribution of force imposed below the waterline due to unconsolidated keels of ice ridges. Only cursory guidance is provided by the standards associations and their analytical design equations. Close inspection of those formulae show that force estimates can become excessive in situations where the expected keel depth is great compared to the designed structure width. Such scenarios would be expected in offshore oil and gas operations where drilling risers, jack-up legs, and even jacket structures may be exposed to ice ridges.
The present work examines available approaches for evaluating ridge keel forces, including passive pressure calculations. The processes of ice rubble failure and the corresponding stress distributions are considered in the context of classical soil mechanics applied in geotechnical engineering. Design standards are also used to calculate ice forces for a range of ridge keel properties, keel geometries, and structure design widths. Field measurements from the Norströmsgrund lighthouse and the offshore Molikpag caisson are then examined and compared to the forces obtained using these approaches.
The authors conclude that the shape factor adopted in ISO 19906 plays an important role in calculations considering narrow structures and deep keels. It is also shown that the sensitivity of ridge keel load calculation to geometric factors varies considerably with structure width. Furthermore, an absence of real world data from ridge keel interactions with very narrow structures precludes validation of present models in these situations and should be the focus of data collection and model refinement.
Modelling Iceberg-Topsides Impacts Using High Resolution Iceberg Profiles
Authors: Stuckey Paul , Younan Adel , Burton Robert , Alawneh Shadi 
Published: November 2016

Abstract
Platforms operating in arctic and subarctic regions such as the Grand Banks, Labrador Sea, Barents Sea and offshore Greenland are exposed to the risk of iceberg impacts. These structures must be designed to withstand the impact from an iceberg or be designed to disconnect and move offsite to avoid the impact. Offshore Newfoundland, gravity based structures (GBS) such as the Hibernia and Hebron platforms are designed to withstand an impact from an iceberg. However, current accepted practice is not to design the topsides for impact, but to reduce impact risk to an acceptable level by varying the facility geometry (i.e., topsides elevation or footprint).
An analytical model was developed to estimate the frequency of icebergs impacting the topsides using three dimensional (3D) models of the platform and the icebergs. Random shapes and sizes are simulated for each iceberg and 3D shapes are generated using a database of measured 2D iceberg profiles. The iceberg shapes are placed randomly in close proximity to the structure and are set to drift towards the structure in a straight line. The initial point of contact between the iceberg and the structure is determined. Crushing of the iceberg against the platform caisson is considered. The process is repeated a large number of times and the total number of contacts with the topsides are determined.
In 2012, Hibernia Management and Development Company Ltd. (HMDC) sponsored a field program in which high resolution iceberg profile data were collected. The high resolution iceberg profiles contain detailed 3D information of the above water and below water shape of the iceberg. This paper describes updates to the existing-topsides impact model to take full advantage of the detailed 3D iceberg profiles. These updates include new iceberg shape databases for simulation, and the addition of a detailed iceberg management model and a graphical user interface (GUI) to improve the functionality of the software.
Airborne Ice Thickness Measurement System - Opportunities and Impacts
Authors: Power D. , Stuber T. , Rowsell D. , Zakharov I. , Fowler C. , Garas Yanni V. , Yi X. , Power B. , Green S. , Ryan J. , Hale S. 
Published: November 2016

Abstract
In ice frequented regions, the potential for large ice floes and extreme ice features encroaching on offshore structures can be significant. An early warning system is desired to discriminate between thin ice of no risk and thick ice with significant challenge. The severity and variability of ice conditions will affect the feasibility of operating in such a region, with significant impact on the design and selection of resources to be used and the ice management requirements to support exploration and development. By measuring the ice thickness, operators can determine the operational risk for ice management operations. In addition, it can help map the areas of thin ice to aid shipping route selection. Despite its fundamental importance, sea ice thickness is one of the most difficult measurements to obtain via remote sensing. Passive remote sensing methods at the near infrared, thermal infrared and visible electromagnetic wavelengths, are restricted due to fog, precipitation, clouds, and Polar darkness. Thus active sensing techniques are deemed to be the only feasible method of measuring ice thickness, especially if they can be mounted in aircraft or satellites. Technical solutions are available to measure the thickness of sea ice, but they do not provide a physical measurement over a wide swath of ice. Thus, the authors are developing a wide swath ice thickness measurement system to fill this gap. The most practical solution for ice thickness measurement is an airborne radar. The authors have completed the preliminary design of a system that will combine an ice penetrating radar with a microwave synthetic aperture radar (SAR). The penetrating radar will be used to glean physical measurements of ice thickness, to be fused with the wide swath SAR to produce an ice thickness map.
Shore Crossing Design Considerations & Solutions for Arctic Subsea Pipelines
Authors: Eisler Ben 
Published: November 2016

Abstract
This paper summarizes the shore crossing options and considerations associated with Arctic subsea pipelines. A summary of what has been installed as well as other options not yet installed are covered. Some options have been ruled out for some projects, and while at the same time, they are either actively being pursued or may be in the process of consideration for other projects.
Offshore project development in the Arctic may utilize pipeline tiebacks to shore. These tie-backs will require a shore crossing transition. There are design aspects for Arctic shore crossings that are similar to non-Arctic conditions. However, in many locations in the Arctic, there are unique Arctic- specific conditions that will influence the shore crossing design details. These Arctic design influences may be of a technical or non-technical nature. Both types of influences may require consideration of technologies and techniques that might not otherwise be considered for non-Arctic locations. These influencing factors will affect almost every aspect of the work as follows:
pre-planning work, which includes geophysical and geotechnical site investigations the design details for the shore crossing, which is the ultimate goal of the work construction techniques, which are required to bring the design to fruition operating requirements and monitoring for the life of the development
One of the main conclusions is that the project and site specific conditions will influence the available shore crossing design options for a project, the option that is ultimately selected for a particular Arctic pipeline project, and the design details required for that project. The site conditions at one project location may be different than the site conditions at another project location, regardless of distance between the two projects. While two different projects at two different locations may utilize the same shore crossing method, the relative costs between the two project's shore crossings may be different due to more conducive site-specific conditions at one location versus less conducive site- specific conditions at the other.
There are several Arctic subsea pipeline projects with shore crossings that have been successfully designed, constructed, and have been operating without incident for more than 15 years. Each illustrates that, despite the increased costs and effort compared to non-Arctic shore crossings, the industry has "been there and done that" safely.
Icebreaker OTSO Conversion
Authors: Salminen Jukka , Eva Seppo , Ekegren Tom 
Published: November 2016

Abstract
This paper will describe the design work and conversion work of icebreaker Otso from Baltic icebreaker to Polar class icebrekaer. Paper will include also user experience from the Arctic after the conversion work.
In April 2015 Arctia signed contract with one of the seismic companies which is operating in the Arctic and the conversion project for fulfilling the rules for worldwide trade and Arctic waters started. The schedule was very tight but all the modifications were made in time and the vessel was ready for Arctic operations in July 2015.
In order to increase vessel utilization outside of the Baltic icebreaking season Arctia Offshore have been studied different kind of solutions during the last ten (10) years. Numerous meetings and planning with naval architects, model tests in ice tank and open water tank was made and during the spring 2015 we had final plans what would be required in order to operate icebreaker Otso in the Arctic. Our requirement was that the open water behavior needed to be close to our multipurpose icebreakers Fennica/Nordica and modifications will not reduce icebreaking capability.
Icebreaker Otso was originally designed and classed to operate in the Baltic Sea in first year ice conditions and was not designed to do ocean passages. Using Otso in the Arctic has been restricted by open water characteristic, ice class and trade area (classification) restricted to domestic (Finnish, Baltic Sea) waters.
Modifications were performed by Rauma Marine Constructions at Rauma Shipyard and included:
New Flume tank to reduce rolling effect in open water conditions
Steel work in the hull, ice class upgraded
New lifeboats installed for worldwide operations standards
New helicopter deck for client use
New hospital for worldwide operations standards
SOLAS and 5 years docking according to the class regulations
Mezanine deck above the Flume tank was installed
Recycling station installed on Mezanine deck
Our experience is that now after three months operating in NE Greenland that the modifications we made are working. This investment was good example that old vessels can have new life and solutions are working. Cost save was massive compared to new build icebreaker.
This conversion shows that it is possible to increase utilisation of old icebreaker and a vessel can have new life
Offshore Ice Resistant Liquid Natural Gas Export Terminal Concept
Authors: Lewis James , Prescott Neal , Thomas Jacob , Swenson Joseph 
Published: November 2016

Abstract
Cost and delivery of long distance natural gas pipelines to a distant LNG (liquid natural gas) liquefaction facility at a warm water port location has become excessive and environmental restraints have been increasing. An alternative to this type of facility is now being considered: an offshore ice resistant LNG Port accommodating a new class of LNG transport vessels. Improvements in LNG processes have reduced the footprint of the facility by 2/3 and lowered the cost by 20% giving an advantage to an offshore ice resistant port facility that can be used for offloading LNG which will eliminate the long distance natural gas pipeline. The presentation is based on original analysis.
The benefits for deep water Arctic Marine Port are undeniable. It is possible to provide safe harbor and configure the port to fit the requirements of the endeavor. For Arctic offshore LNG liquefaction operations, this port can be designed to provide safe harbor and be relocated if needed to another site. A system of ship-like rectangular GBS (Gravity Base Structure) type structures can be constructed to create a safe area where there would be no ice movement and would provide shelter from large wind storms. The structures could be constructed in the Pacific Rim and towed to the site of the new port. They would then be ballasted into position.
For the Beaufort Sea, the port could be positioned offshore west of BP's Northstar Island in approximately 60ft. of water. The ice movement is benign and units can be readily designed to resist the ice loads. Life expectancy would be greater than 20 years.
The concept is extremely adaptable to the location and type of deployment. The Ice Resistant LNG Port System would be designed to accommodate the shallow waters of the near shore Arctic seas. In addition, the individual units could be configured to serve multi-functions in the exploration and development of offshore hydrocarbon fields. These units could be configured to provide shallow water drilling GBSs and or storage for offshore operations or both.
Advances in ice class LNG transport vessels developed for the Russian Arctic allows the discharge and transport of LNG by sea, thus eliminating long distance natural gas pipelines. The new LNG carriers being designed for the use at the Yamal project are capable of breaking through ice 2.1 meters thick and newer designs will be capable of breaking 2.5 meters ice unassisted. These new vessels are to enter service in 2016 and haul the LNG to the Pacific-rim countries. The vessels are 299 meters long and draft 12 meters.
Design and Construction of North America's First Major Bridge North of the Arctic Circle
Authors: Braun PE K. W. , Brodie J. I. , Fitzpatrick M. R. , Anderson A. 
Published: November 2016

Abstract
The Colville River originates in the remote western Brooks Mountain Range in Alaska's Arctic and empties into the Beaufort Sea, a marginal water body of the Arctic Ocean. The river, which is frozen for more than six months each year and floods in spring, is approximately 560 kilometers long and is one of the northernmost major rivers in North America. The river separates the established oil and gas fields of Alaska's North Slope from the previously undeveloped National Petroleum Reserve - Alaska (NPR-A) to the west. A key component of required infrastructure to accommodate development of the resources was a series of four bridges across distributaries of the Colville River that provided access between the Alpine Field and NPR-A. The longest of the four bridges was a 430-meter structure across the Nigliq Channel, the largest distributary of the Colville River. This paper describes the significant design and construction challenges that had to be overcome to successfully complete the Nigliq Channel Bridge.
Simulation of Iceberg Impacts Using Ice-MAS: A Design Tool for Simulating Ice-Structure Interactions.
Authors: Béal Pierre-Antoine , Yaouanq Sébastien Le , Septseault Cyril , Cahay Marc , Roberts Brian , Mravak Zoran 
Published: November 2016

Abstract
Exploitation of the Arctic's resources requires the mastery of the risks caused by extreme ice conditions. The design of offshore structures subjected to extreme ice conditions is a challenge for engineers since there are very few advanced design tools available on the market, especially those able to cope with the large variety of ice interaction and failure mechanisms.
Different approaches have been used to model and study ice behavior. Among them are analytical, numerical and empirical approaches with different models being considered. Each model has its own advantages and drawbacks and is only generally dedicated to certain circumstances. In 2012 Technip, Cervval and Bureau Veritas initiated a common development program to offer a new tool for the design of offshore structures interacting with ice (Septseault, 2014, 2015) combining a variety of approaches and models.
After three years, the first version of the Ice-MAS software (www.ice-mas.com) is now available. It simulates the ice loadings on a structure and the dynamic behavior of the drifting ice-sheet and floes around. Thanks to multi-agent technology, it is possible to combine in a common framework multiple phenomena from various natures and heterogeneous scales (drag, friction, ice-sheet bending failure, local crushing, rubble stack up) (Le Yaouanq, 2015). This work has been the subject of numerous validations, particularly by comparison with ice basin and in-situ results (Dudal, 2015).
The Ice-MAS development program continues in 2016 with the addition of a capability to model the interaction of icebergs with offshore structures. This paper will introduce the co-simulation architecture proposed to simulate the complex interaction between an iceberg and a platform structure. It will focus on the hydrodynamic behavior of the platform and the iceberg including its stability. It will also consider the interaction between both bodies; including the non-linearity of the mooring system (in the case of a floating platform) and the local fracture mechanisms of the iceberg. The objective is to propose a new more accurate design method that will improve the overall ice management system for a project.
Estimation and Validation of Floe Size Distribution from Upward Looking Sonars
Authors: Mudge Todd , Borg Keath , Ersahin Kaan , Ross Ed , Sadowy Dawn , Barrette Jessy 
Published: November 2016

AbstractMoored upward looking sonars (ULS) have been used extensively for over twenty years to measure sea ice draft thicknesses and ice keel widths. They have rarely been used to analyze ice floe sizes. In 2015, Statoil Canada, ArcticNet, the Research & Development Corporation of Newfoundland and Labrador (RDC) and Husky Energy partnered in an offshore research expedition, a component of which was Ice Profiler Sonar (IPS) and Acoustic Doppler Current Profiler (ADCP) measurements in waters off Newfoundland. This provides an excellent opportunity to develop methods to estimate floe size distributions in the marginal ice zone. IPS data is typically analyzed for ice draft and for the presence and absence of sea ice. ADCP bottom tracking data during periods of high ice concentrations provides direct measurement of ice drift. Deriving these ULS-based parameters in the low concentrations and often energetic wave environment of the marginal ice zone is difficult. A six-day period of relatively low wave energies was analyzed for ULS derived ice floe sizes. Over 1000 floes were detected with most of the detected widths being less than 30 m and a peak in the distribution at less than 10 m. Ice concentrations and ice drifts as derived from the ULS were similar to those reported by Canadian Ice Service daily ice charts. Analysis of both theoretical and natural ice floe shapes suggests that the average of the ULS determined ice floe widths is typically about 70 to 80% of the equivalent diameter and about 55% of the typical maximum horizontal extent. Thus, much of the ULS detected floes were likely smaller than the resolution of satellite imagery. As the ULS moorings measure ice draft every one or two seconds and ice speeds every one minute, estimates of average floe mass, momentum and energy of ice features observed during the six-day analysis episode were possible.
The influence of culture on female entrepreneurs in Zimbabwe
Authors: Mazonde Nomusa B. , Carmichael Teresa 
Published: November 2016

<strong>Background:</strong> There is an increasing interest in female entrepreneurship, not only to realise the potential for economic growth, but also in light of the opportunities for female expression, emancipation, agency and empowerment. Literature has found that many female entrepreneurs are profoundly affected by the traditional sociocultural context in which they operate, and that they have needed to work around patriarchal barriers in order to succeed. This study explores the ways in which they do this.<p><strong>Aim:</strong> The aim of this paper was to contribute to an understanding of how female entrepreneurs in a patriarchal African society can work within cultural constraints to achieve success within their own terms of reference.</p><p><strong>Setting:</strong> The study took place in Zimbabwe among female entrepreneurs who had recently formalised their businesses</p><p><strong>Methods:</strong> Using a qualitative interpretive research design, in-depth, face-to-face interviews were conducted with 43 African female entrepreneurs running their own businesses in the Zimbabwean cities of Harare and Bulawayo.</p><p><strong>Results:</strong> The complex interplay of macro- (national cultural characteristics), meso- (institutional and social factors), and micro- (individual identity) level factors shaped the ways in which the women dealt with the shackles of patriarchy, inequality and high power distance that had historically impeded their economic participation. Through their own agency, they mobilised their public and private identities separately, balancing the seemingly incompatible roles of home-maker vs entrepreneur.</p><p><strong>Conclusion:</strong> Zimbabwean women successfully managed the interaction between their different social roles and identities to balance domestic obligations with income generation to better the lives of their families.</p>
Echinococcose alvéolaire : actualités 2016
Authors: Bresson-Hadni Solange , Angèle Vuitton Dominique 
Published: November 2016

L’échinococcose alvéolaire (EA) est une cestodose larvaire rare, due au développement dans le foie de la larve d’Echinococcus multilocularis. Sa progression s’apparente à celle d’un cancer à marche lente. En France, les caractéristiques épidémiologiques de l’EA se sont modifiées récemment. Les foyers endémiques restent localisés à l’Est et au Centre du Territoire, mais la limite occidentale de la zone d’endémie française dépasse désormais Paris et concerne également les zones urbaines. Le registre français des cas indique par ailleurs une augmentation de l’incidence annuelle. Elle est probablement surtout la conséquence d’une amélioration significative des techniques de diagnostic, en particulier de l’échographie, examen de première ligne pour le diagnostic de cette affection. Le développement de thérapeutiques immunosuppressives (chimiothérapie, biothérapie) pour diverses pathologies peut fournir une deuxième explication, avec l’observation croissante de cas d’EA découverts en situation d’immunosuppression. La maladie est repérée plus tôt dans son cours évolutif, très souvent à un stade asymptomatique. L’ictère qui, par le passé, révélait l’EA dans la moitié des cas, n’est aujourd’hui que très rarement présent au diagnostic. La chirurgie est restée jusque dans les années 1980, la seule et unique solution pour son traitement, souvent palliatif. Des options complémentaires, ou distinctes, sont apparues au cours de ces trente dernières années : administration d’albendazole exerçant un effet parasitostatique, radiologie interventionnelle, transplantation hépatique en cas d’EA évoluées. Toutes ces acquisitions, associées à un diagnostic généralement plus précoce, aux progrès des techniques d’imagerie et de la chirurgie hépatobiliaire ainsi qu’à une approche multidisciplinaire de cette prise en charge, ont permis d’améliorer considérablement le pronostic.