bluuebunny/crossref_metadata_2025 huggingface dataset:
The Enhanced Safety Case Approach for Incorporating Environmental Impact
Authors: Kuo Chengi
Published: September 2011

The paper is concerned with integrating the effects of environmental impact into the methodology of safety management based on the fresh concept of an enhanced safety case (ESC). There are two key reasons for this approach. Firstly, it would enable both safety and environmental effects to be addressed by the same management system instead of treating them by different approaches. Secondly, preparing safety cases is familiar to the offshore oil/gas industry and there is no need to learn an alternative methodology. However, ESC is formulated by starting with a generic management system circuit linked to safety and environmental impact (EI) schemes. The main conclusion is that ESC is a versatile and practicable method and further research studies are in progress to explore its additional usage.
Statoil North Sea – Successful World Record MLT Installation
Authors: Eck-Olsen Johan , Solheim Ove Andre , Falnes Morten
Published: September 2011

In October 2010 the deepest set sealed multilateral junction in the industry was installed at 6900 m MD in Oseberg South well 30/9-F-9 AY1/Y2.

The differential pressure across the junction in the well is expected to be in the range of 250 bars. To meet this pressure requirement, a multilateral (ML) junction rated to 370 bars was identified. The high pressure junction components and entire multilateral system has undergone an extensive testing and qualification program, including several component tests and a full scale system interface and integration test.

A 10 ¾″ pre-cut window with an outer aluminium tube was installed as an integral part of the 10 ¾″ liner. The plan was to perform the milling operation through this window. A stuck string incident during the 10 ¾″ liner installations accidentally caused the liner to drop in hole. The liner ended up at the wrong orientation, and the window could consequently not be used.

The mainbore was drilled to TD at 8583 m MD and the 7″ liner was run and cemented. After the liner perforation the MLT operations started with the installation of a multilateral anchor packer to allow for installation of a latch interface assembly (LIA) and milling system. The LIA was installed and locked into the multilateral packer on a separate run.

The milling operation was done in a two step operation with milling of a 1st pass window using a 10 ¾″ milling machine prior to installation of whipstock and performing the 2nd pass milling operation.

The lateral branch was drilled to TD at 8258 m MD and a 5 ½″ screen completion was run and dropped off into the 8 ½″ open hole. The drilling whipstock was retrieved from the well and a completion deflector was installed. The junction was finally stung into the deflector, simultaneously as an open hole seal stinger entered top of the screen liner in open hole, tying the branches together.

A 6900 m long upper completion string with inflow control valves was finally installed to allow for surface control of the two branches.
The Autonomous RCP Valve - New Technology for Inflow Control In Horizontal Wells
Authors: Mathiesen Vidar , Aakre Haavard , Werswick Bjørnar , Elseth Geir
Published: September 2011

Horizontal wells with one or more branches have been used to maximize reservoir contact by Statoil and other oil companies for more than a decade. Frictional pressure drop and variation in permeability and mobility will naturally lead to non-uniform inflow profile along a well. Eventually, this will result in gas and/or water breakthrough, which may reduce the well performance and recovery significantly. The breakthrough typically occurs in the heal region of the well and in regions with high reservoir permeability. Inflow Control devices (ICDs) are flow resistance elements installed along the producing zone of a well to counteract the non-uniform inflow, hence improving the well performance. The technology is regarded as standard technology by the industry and classified as passive inflow control, since the geometry of the devices is fixed or preset prior to installation. Passive inflow control is applied to delay the unwanted gas/water breakthrough. However, once occurred, conventional inflow control will not reduce or stop the breakthrough. Statoil's new autonomous inflow control device (AICD) is an active flow resistance element distributed along the well, similar to conventional passive ICDs. Statoil's AICD will, in addition to delay the breakthrough, reduce the proportions of the breakthrough. The AICD will impose a relatively strong choking for low-viscous fluids and only minor choking for viscous oil. This is due to autonomous changes in the flow area internally in the AICD. With this technology the well performance and production can be higher after a breakthrough compared to conventional inflow control.

Statoil's AICD technology is piloted in two wells at two different fields in the North Sea. Each well is completed with 1-4 AICDs per screen joint, typically 200-400 per well. The AICD operates without need for human interventions and electric or hydraulic power. Well tests have shown that Statoil's AICD technology reduces the inflow of gas into the well from a reservoir containing light oil. Due to the restriction of the gas inflow, the drawdown can be kept high after breakthrough to allow significant oil production from the remaining oil zones in the well.

Likewise, in a pilot well in a reservoir containing heavy oil, well tests have shown that Statoil's AICD technology reduces the inflow of gas into the well and preliminary evaluations indicate that even water inflow is reduced. Thus the drawdown can be kept high allowing high production from the remaining oil zones.
The Activities and Recommendations of the UKCS OSPRAG Technical Review Group Following the Deepwater Horizon, Macondo Incident
Authors: Kinkead Brian
Published: September 2011

Following the Deepwater Horizon incident the UK Upstream Oil and Gas industry formed Oil Spill Prevention and Response Advisory Group (OSPRAG) in May 2010. The Technical Review Group (TRG) within OSPRAG was tasked with reviewing relevant aspects of well design, examination, primary and secondary well control and to consider a UK capping contingency in the event of a loss of well control.

This paper will examine the formation of the TRG and its approach to assessing whether the UKCS industry was performing in accordance with the regulatory requirements. It will examine the core TRG recommendations and assess how they are being implemented largely through the formation and work of Oil & Gas UK's Well Life Cycle Practices Forum (WLCPF). This includes the importance and relevance of assessing the future recommendations from the Macondo incident.

Finally, the experiences and effectiveness of working within a cross industry team with members drawn from across industry including regulators, operators, contractors and trade unions will be discussed.
Qualification of the Deepwater Subsea Well Intervention System "AX-S" for 10,000 ft Operations
Authors: Svensen Matthew , Williamson Robbie , Law Matthew
Published: September 2011

This paper presents a detailed description of the technology qualification for the novel deepwater subsea well intervention equipment, the "AX-S™ system" developed by Expro AX-S Technology Ltd, and how the statement of feasibility of the project was developed and successfully achieved. Using the framework for technology qualification - Det Norske Veritas’ recommended practice "RP-A203: Qualification Procedures for New Technology", DNV and Expro AX-S overcame a series of challenges to deliver the first project milestone (statement of feasibility) while ensuring that the project timeframe was not impeded. The Expro AX-S subsea well intervention system can operate in depths of up to 10,000 feet and negates the need for a drilling rig and riser systems, instead using remote intervention from a dedicated monohull vessel.
Ensuring the Integrity of Subsea Hot Tap Welded Joints in Lieu of Hydro Testing
Authors: Smith Alan , Williamson Robbie , Low Andrew
Published: September 2011

Hot tapping of subsea pipelines is a cost effective method of transporting production fluids from satellite wells into existing pipelines. The process involves welding a branch connection onto a flowing operational pipeline and trepanning a coupon from the outside of the mother pipe. The technique is now well established and can minimise production down time. In most cases, the integrity of the branch weld is proven via subsequent pressure testing to prescribed limits based upon a multiple of the anticipated design pressure. However, in exceptional cases, such strength testing may not be possible. If this is the case it may be necessary to ensure the integrity of the welded joint by non destructive testing. This paper examines the use of non destructive testing and specifies the issues which need to be considered and the process involved in qualifying a Hot-tap weld. The use of NDT is justified by reference to the fracture toughness of the weld and associated microstructure and is based on a fracture mechanics argument. The paper draws on experience gained in the practical application of this methodology offshore.
Qualifying an External Turret and Mooring System for the Offshore Industry
Authors: Ogosi Eugene , Williamson Robbie , Galbraith David , Donovan John
Published: September 2011

This paper presents the procedure used in and benefits of applying a cost-effective method for qualification of an innovative external turret and mooring system. The system has been developed by Sigma Offshore Limited for application in the offshore industry. Qualification of technology is a major challenge to the offshore industry particularly in the oil and gas sector, where it is essential to demonstrate the applicability and operational reliability of new technology before it is applied. Technology qualification in this case essentially increases the operators’ confidence in the technology. It assists the contractor to improve on the design of the proposed technology in order to comply with strict safety standards and meet the technological challenges of the industry.

The Sigma Offshore Smart Mooring System (SMS) is an external turret and has been designed to provide an FSO/FPSO mooring and fluid transfer solution which is intended to minimise hull invasion, provide a cost-effective on-site installation option and allow unlimited weathervaning of the vessel. The Sigma SMS can be installed on the vessel without the need to dry-dock allowing for significant installation cost savings. The SMS contains a unique Gimbals system which comprises bearings acting around 3 perpendicular axes, together with the steelwork to connect them and carry the forces between a canister attached to the risers and mooring lines and the cantilever attached to the FSO/FPSO.

The method which has been applied in the qualification of this technology is based upon the existing framework for the technology qualification - ‘Det Norske Veritas’ recommended practice "RP-A203: Qualification Procedures for New Technology’’. This recommended practice (RP) describes a systematic and generic work process that is ideal to qualify such new technology. The benefits of the qualification method were demonstrated by applying it to the SMS with the resultant identification of key improvement in the design consideration, system reliability and reduction of risks before first implementation.
High-Density OBC—A Step Change in Reservoir Imaging—A BP North Sea View
Authors: Davies Daniel , Mannaerts Herlinde , McGarrity John , Ibram Mark , McKenzie Colin , Campbell Steve , Alexander Gino , Lozano Angeles , Kommedal Jan , Barkved Olav , Van Gestel Jean-Paul
Published: September 2011

BP is committed to a long term future in the North Sea Region. Delivering this promise will rely on continued exploration and appraisal success within the basin as well as efficient and cost effective resource progression through infill drilling and enhanced hydrocarbon recovery schemes in generally mature fields. To maintain track record, drive higher field recovery and progress infill drilling, it was realised that availability of current, fit-for-purpose seismic data is a key enabling technology.

This paper looks back on BP North Sea experience of using Ocean Bottom Cable (OBC) seismic data. Since 2002, BP has acquired at least two OBC surveys per year in the North Sea to support the appraisal and development of fields, with significantly more fields covered. Since 2009, this has been increased and we are averaging nearly 5 surveys per year.
Unlocking the Future for a Mature Field: Surveillance and Complex Wellwork Combine to Extend Field Life
Authors: Dunning Matthew , Stripe John , Keatinge Patrick , Newton Peter , Davies Ann , Waugh George
Published: September 2011

Ravenspurn North is a mature gas field forming part of BP’s UKCS portfolio. The field commenced production in 1990 through 42 wells and 3 platforms but by 2006 half of the wells had ceased to flow. Surface pressures suggested limited remaining gas and, with declining production, the field was at risk of abandonment.

A surveillance campaign carried out in 2006 suggested a common failure mode for many wells, which postulated that large amounts of proppant had accumulated in the wellbore. Pressures measured downhole above the proppant fill supported a significant increase of the remaining gas potential.

A project to rejuvenate this field was initiated in 2007. The key to this project was cleaning out and reinstating non-flowing wells across the field. This would require pushing the boundaries of cleanout techniques and delivering a number of industry firsts, all on normally unmanned installations with complex logistical challenges. Additionally, each individual well intervention would be economically marginal on a standalone basis - the project had to place these interventions into a wider business context before building the case to justify the investment needed to resolve the many challenges presented.

This paper details the journey to maximise the potential of the mature Ravenspurn North field. It starts with the acquisition of surveillance in 2006 and covers how the business case was built to justify one of BP’s most complex well intervention programmes in the North Sea (concentric coiled tubing vacuum technology on a small unmanned platform). It culminates in the successful execution of the first phase of wells in 2010.

With the first phase of the Ravenspurn North rejuvenation complete, this paper reflects on the lessons learned along the way and identifies the key activities which have contributed to delivering a longer, brighter future for this field.
Innovative Web Portal Reservoir Knowledge Base Integrates Engineering, Production, Geosciences and Economic Data Sets
Authors: Rees D. , Reichardt J. , O’Carroll A.
Published: September 2011

This paper describes a novel web portal, which has been created for the North Sea area to meet the need for a knowledge base of reservoir and engineering data targeted towards exploration and production professionals to assist them in evaluating prospects and projects, assessing development risks, and measuring prospects against other opportunities in their company portfolios. Operators in the deepwater Gulf of Mexico have found a similar service an invaluable resource when researching analog fields, as reservoir assessment and benchmarking are at the heart of good appraisal, sanction and development decisions. Through utilizing analogous data, decision makers can evaluate assumed data based on its statistical place in similar fields and geological regions. When analytics are performed in this manner, uncertainty risk can be reduced.

The North Sea knowledge base features innovative applications, including a GIS interface and a set of analytical tools, and is maintained and supported by a team of engineers and geologists who provide analysis, case studies, and statistics on key data and fields.

Directed towards exploration, appraisal and development teams in the North Sea area, the knowledge base contains coverage of all productive sands discovered, reservoirs either currently in production or sanctioned for development. The service provides regularly updated reservoir metrics and analogs, and offers a unique combination of reservoir engineering, geological, production, facilities and economic data analysis, together with regional knowledge.

Users may also leverage the public domain information and analysis in the knowledge base by deploying secure servers in-house to store, manage, and compare proprietary data with the data and data analysis stream provided. This model leverages internal security systems to keep client data safe, while providing their engineering, geologic, and other subsurface technical staff with a single stop for current asset status, up-to date analogs, play and regional data, and both internal and external best practices, case studies, and literature, etc. With an extendable data model to manage structured and unstructured data, this solution provides a framework to ensure that exploration and asset teams can access all data of immediate interest, and also highlights other key knowledge related to specific prospect, appraisal and or development evaluation needs.
Application of Particle Swarm Optimization for Parameter Estimation Integrating Production and Time Lapse Seismic Data
Authors: Rwechungura Richard , Dadashpour Mohsen , Kleppe Jon
Published: September 2011

The purpose of reservoir modeling is not only to build a model that is consistent with currently available data, but also to build one that gives a good prediction of its future behaviour. Updating a reservoir model to behave as closely as possible to the real reservoir is called history matching, and the estimation of reservoir properties using this method is known as parameter estimation and it is an inversion process.

Here we apply one of the evolutionary algorithms (Particle Swarm Optimization – PSO) to estimate porosity and permeability using both production and 4D seismic data. PSO is a population-based stochastic optimization algorithm. It is known as a swarm intelligence algorithm because it was originally inspired by simulations of the social behaviour of a flock of birds. The method combines simplicity in implementation and high capability for distributed (parallel) computing.

The results obtained on a 2D section of the Norne Field in the Norwegian Sea, demonstrate that this parameter estimation approach combines moderate computational requirements and better objective function values and exhibits good ability to handle history matching problems without exhaustive sampling of parameter space.
CO2 Monitoring: Taking the Pulse of CO2 Storage Reservoirs
Authors: Clyne Hazel , Phillips Ian , James Alan
Published: September 2011

This paper provides an overview of the current legislation regulating the deployment of carbon capture and storage (CCS) in the European Union, and examines how this regulation dictates the selection, implementation and long term use of monitoring technologies at CO2 storage sites onshore and offshore.

We consider the wide range of purposes and objective that a CCS Monitoring Plan has to meet, and the resulting wide range of parameters that it is necessary to monitor. We also assess some of the practical considerations that may render a particular technology viable in one reservoir, and completely inappropriate in another reservoir.

The authors conclude that the monitoring plan will be highly site dependent. We also note that there exist a wide range of cost-effective and readily deployable wellbore logging and monitoring tools developed for the oil and gas industry, which have direct applicability to the monitoring of a CCS storage site and complex. However, the unique attributes of CO2, and the significant difference in the monitoring objectives when compared with oil and gas activity means that there is significant potential for new technologies to improve CO2detection in the subsurface and to reduce costs.
BP North Sea: Introduction and Compliance with BP's Aviation Group Defined Practice: Group Defined Practice 3.7 - Aviation
Authors: Combe Alan , Parker John , MacLean David
Published: September 2011

The requirements for the Management of Aviation Risks is set out in BP Group Defined Practice (GDP) GDP 3.7-0001 Aviation, covering all aspects of the operators contracted services and the management of these services, to include safety management systems, operations, flight crew and engineering training and experience, passengers and freight, aircraft equipment standards and Emergency response planning.

GDP 3.7 was issued in October 2009 with a requirement for all new or extended contracts for Aviation services to be conforming at either the contract renewal date or by 31st December 2010 for existing contracts. A tight timescale given the need to change contracts, add equipment, change aircraft in some cases and gain agreement with our operators in order to meet the additional requirements.

BP North Sea declared full conformance with GDP 3.7 for all our Aviation crew change and Search and Rescue contracted operations ahead of the required conformance date of 31st December 2010.

To declare full conformance, a gap analysis was completed over a number of months supported by each of our contracted operators with contracts updated to meet all GDP requirements. The BP Group Defined Practice used the Aircraft Management Guidelines – the industry best practice - published by the International Association of Oil and Gas Producers as the basis for GDP 3.7. We have reinforced the content of the original document by mandating many elements to standardize the way in which BP approaches Aviation Safety and operations globally. We have added content from our own lessons learned to drive continuous improvement throughout our business.

Conformance with GDP provides enhanced safety by adopting the most recent technical advances in aircraft equipment by mandating systems such as Traffic Collision Avoidance, Ground proximity warning, Automatic Float Deployment, External life rafts and Operator Satellite flight tracking for all BP Aviation operations.
Workflows and Considerations for CO2 Injection in a Highly Depleted Gas Field in the Southern North Sea
Authors: Webster C. McK. , Zhang Y. , Park D. , Gibbons K. A.
Published: September 2011

Issues and associated mitigation measures for Carbon Capture and Storage (CCS) relating to capacity, injectivity and integrity of the storage site are not trivial. Modeling of CO2 injection along wellbores is still in its infancy compared with traditional hydrocarbon modeling. While a significant amount of work has been done with respect to modeling discrete components of the storage site and associated infrastructure, validation of our modeling tools and the results still remains uncertain, particularly with respect to two phase flow in the wellbore.

This paper presents a workflow for injection of CO2 into highly depleted gas fields, addressing the issues around injection modeling and the impact on surface facilities, well design and the near wellbore interface. These include: obtaining accurate predictions of phase behavior, density, and viscosity, determining the impact of delivery pressure and temperature versus reservoir conditions. Wellbore design issues such as sizing and load resistance of tubulars and metallurgy selection in order to ensure both injection performance and integrity must also be considered. Modeling CO2 in the reservoir is also discussed considering the near wellbore effects (cooling and potential ice / hydrate formation). Finally, short and long term monitoring issues are identified and the benefits and limitations of the various monitoring options are discussed.
Strategies for Minimising Carbon Emissions from Facilities whilst Improving Opex
Authors: Guinee Mike
Published: September 2011

Conservatively, at least 4 million boe are consumed daily and around 500 million tonnes of CO2 emitted annually from upstream oil and gas operations worldwide. There is a huge economic prize and an urgent business need to improve upstream energy efficiency, particularly since the carbon emissions from this industry are alleged to be one of the major contributors towards climate change.

The UK government has just introduced targets to reduce Green House Gas (GHG) emissions by 50% by 2025. Hence it is about to introduce increased legislation for carbon emissions from 2013 onwards that will impose significant additional Opex for all operators that, as yet, is not fully appreciated by the upstream industry. This additional levy may have the undesired affect of bringing forward the economic cessation of production date and reduce the ultimate recovery from each field.

This paper gives a concise background on the legislation, details of the regulatory framework and its likely impact on an asset’s CoP date. Lessons learned from over 200 energy assessments conducted in the UK and internationally will be shared as to how Operators can reduce their commercial exposure by using state-of-the art energy reduction tools and techniques. Selected case studies will be described with costs and benefits highlighted.

This experience has been gained by the author in reducing carbon emissions across a broad spectrum of Operators and asset types over the last twelve years. It will be shown that many of the tools and techniques provide quick fixes that can help to reduce carbon emissions by over 10%. This paper will also highlight how production is often increased as a desirable by- product of prudent and efficient energy management of operating assets, giving a positive rate of return for any investment needed to improve uptime and efficiency.
The Energy Technologies Institute's UK CO2 Storage Appraisal Project (UKSAP)
Authors: Gammer D. , Green A. , Holloway S. , Smith G.
Published: September 2011

The purpose of the UKSAP project is to provide a realistic, defensible and fully auditable estimate of the capacity of geological formations below the UK's coastal waters to store CO2. Drawing on the expertise of the project participants (10 UK organisations) and accessing existing public domain and commercially available data, the £3.9M project has created a web-enabled database and geographical information system (WDG). This covers all the potential storage volume in the North Sea, the East Irish Sea and the central English Channel. The WDG is designed to assist policy makers and potential participators in projects with high level assessments and planning.

Storage units in the WDG (several hundred) are described in terms of geographical, geological, geophysical and other data relevant to risks in their use, leading to estimates of their storage capacity and economic profile. The ETI will make the WDG accessible to the public after completion of the project in July 2011.

The paper will present the methodology used in creating the estimates and describe high level findings from analysis of the data. The functionality of the WDG will be outlined.
The Frigg Cessation Project
Authors: Berger Jean-Claude
Published: September 2011

The Frigg Cessation Project was the largest decommissioning project undertaken in the past decade and included the removal of six topsides, three steel jackets and sealines with an estimated weight of 87.000 metric tonnes. The magnitude of the project and the fact that the field straddles the border between Norway and UK makes it unique. Both British and Norwegian statutes apply on Frigg, depending on the location of the platforms. It had been therefore necessary to find an agreement with the relevant authorities of both countries so that the decommissioning of the Frigg field can be handled as a single unit observing both sets of national statutes.

This paper presents a brief description of the Frigg field with its installations to be decommissioned and disposed of, the process and schedule followed by TOTAL to define the decommissioning scope including public consultation of the stakeholders and preparation of the cessation plans for submission to the regulatory bodies. It will also describe the contracting process followed for the award of the main contracts. Furthermore the paper will describe the main execution phases from the offshore hook down, the removal and transportation to the onshore disposal of the installations and will conclude with some lessons learned from this project.
Improved Characterization and Performance Assessment of Shale Gas Wells by Integrating Stimulated Reservoir Volume and Production Data
Authors: Yin Jichao , Xie Jiang , Datta-Gupta Akhil , Hill A. Daniel
Published: September 2011

Gas flow in shale gas reservoirs occurs primarily from ultra low permeability shale rocks through a complex network of natural and induced hydraulic fractures. Consequently, fracture parameters (conductivity and half length), fracture location and distribution are the dominant factors influencing well drainage volumes and shale gas well performance. Stimulated reservoir volume or SRV, estimated from microseismic event clouds or rate/pressure transient analysis, describes a measurement of overall reservoir volume impacted by fracture treatments. With SRV as well as the dynamic production/pressure response, reservoir simulation models can be calibrated to actual well performance in shale gas reservoirs leading to improved understanding, forecasting and future well placement.

In this paper, we first introduce a novel approach for computing well drainage volume for shale gas wells with multistage fractures and fracture clusters. Next, we calibrate the shale gas reservoir model by matching the drainage volume with the SRV within specified confidence limits. The matching of the SRV is done in addition to the traditional history matching of production/pressure response and further constrains the estimation of fracture parameters. An evolutionary algorithm with design of experiments is used for the assisted history matching. Sensitivities to various parameters such as fracture conductivity, fracture half lengths and rock compaction have also been investigated. The proposed approach has been applied to a generic shale gas well designed after a real field case. The results clearly indicate the benefits of including SRV during history matching, leading to improved fracture/matrix parameter estimation and performance forecasting. Our proposed approach provides an important tool that can be used to optimize well placement, fracture treatments and improve the economics of shale gas plays.
Improved Unconventional Gas Recovery With Energized Fracturing Fluids: Montney Example
Authors: Burke Lyle H. , Nevison Grant W. , Peters Wade E.
Published: September 2011

This February 2011 study compares the production and cost impacts of using energized and non-energized fracturing fluids on unconventional gas wells in the Montney formation. Analysis of roughly 24 to 36 months of gas production show significant benefit can be achieved from energized fracturing fluids and that their use warrants investigation in other unconventional oil and gas plays. There is illustrated potential for significant gas recovery improvement. There is also opportunity to reduce fracturing resources; the most significant of which is water and proppant consumption; there is also opportunity to reduce pumping rate and pressure in some instances. The potential environmental benefit of considerably lowering water consumption is attractive and may, in itself, justify their use. Energized fracturing treatments can cost more; however, the benefits are shown to far outweigh the incremental costs. The opportunity exists to improve unconventional well fracturing effectiveness and to reduce the resources used in those treatments by including nitrogen or carbon dioxide in the fracturing fluid.

Based on the comparative assessment completed on the subject Montney wells in the Dawson Area of N.E. British Columbia, the use of energized fluids is shown to generate significantly improved well performance over those wells fractured with non-energized fluids. On average each well stimulated with energized fluids is forecast to potentially recover between 1.1 to 2.2 times as much gas as non-energized fracturing treatments the Study Areas 1 and 3 respectively.

Area 1 Study compared the performance of Slick Water against Nitrified Slick Water and CO2 Foam fracturing treatments. The production analysis predicts an 11% incremental recovery improvement of 0.29 Bcf by using energized fluids. Though the treatment costs for the energized fracture treatments were seen to be higher, the value of this incremental recovery outweighs the additional cost with no incremental risk. Of note was the opportunity to reduce the fracturing fluid liquid volumes by over half with using CO2 Foam treatments rather than Slick Water. This shows the opportunity to improve production while also minimizing environmental impact. At marginal gas prices of $4.00/Mcf, the value of this incremental recovery approaches $1.4 MM from an incremental fracture cost investment of $500,000.

Area 3 Study compared the performance of Gelled Frac Oil against CO2 Foam fracturing treatments. The production analysis showed a 124% incremental recovery improvement of 3.75 Bcf by using energized fluid fracturing treatments. At marginal gas prices of $4.00/Mcf, the value of this incremental recovery approaches $14.8 MM, from an incremental fracture cost investment of $400,000.
Meat bone meal as fertiliser for barley and oat
Authors: CHEN L. , KIVELÄ J. , HELENIUS J.
Published: September 2011

The traditional production of mineral N and P fertilisers is unsustainable due its reliance on fossil fuels in the case of N, and on limited mineral resource stocks in the case of P. The use of alternative or complementary fertilisers that originate from organic waste materials is gaining interest. Organic farms, especially arable organic farms without livestock, need usable sources of plant nutrients. Meat bone meal (MBM), a potential organic fertiliser for agricultural crops, contains considerable amounts of nutrients (on average 8% N, 5% P, 1% K and 10% Ca). In EU countries, Commission regulation (EC) No 181/2006 authorised the use of MBM as an organic fertiliser. In this study, MBM was compared to conventional mineral NPK fertiliser. Two randomised complete block split-plot field experiments were conducted: one with spring barley (Hordeum vulgare) in two years; and another with oat (Avena sativa) for three years, including a fourth year of testing for residual effect. Compared to mineral fertiliser (20% N, 3% P and 9% K), MBM was applied at three N levels: 60, 90 and 120 kg N ha-1. The grain yield of both cereal species supported by MBM, did not differ from the yield obtained with the mineral fertiliser at any N level. At 120 kg N ha-1, the grain yield level with either type was ca. 4500 kg ha-1 of barley and 5000 kg ha-1 of oat, representing fair averages for Finnish conditions. Moreover, MBM and mineral fertilisation showed no differences in quality in terms of 1000-grain weight, test-weight, protein content and protein yield. Since MBM has a low N/P ratio, P was applied in surplus to attain comparable N levels. Therefore MBM fertilisation should be fitted for crop rotation and for meeting environmental requirements.;
Italian Public Health Care Organizations: Specialization, Institutional Deintegration, and Public Networks Relationships
Authors: Del Vecchio Mario , De Pietro Carlo
Published: September 2011

The Italian National Health Service (INHS) has undergone profound changes over the past three decades. With establishment of the INHS in 1978—a tax-based public health care system with universal coverage—one of the underlying principles was integration. The recognition of health and health care as requiring integrated answers led to the creation of a single public organization, the Local Health Unit, responsible for the health status of the population of its catchment area. At the beginning of the 1990s, the scenario radically changed. The creation of hospital trusts, the development of quasi-market mechanisms and management control tools, the adoption of a prospective payment system for reimbursing health care providers—all were signs of deintegration and institutional unbundling. Two structural changes have deeply sustained this deintegration: patients' empowerment and the increased possibilities for outsourcing practices. In more recent years, a new reintegration effort has occurred, often led by regional governments and based on institutional cooperation and network relationships. However, the earlier structural changes require innovative approaches and solutions if public health care organizations want to retain their leading role.
Assessing Longitudinal Change in Coordination of the Paretic Upper Limb Using On-Site 3-Dimensional Kinematic Measurements
Authors: van Kordelaar Joost , van Wegen Erwin E.H. , Nijland Rinske H.M. , de Groot Jurriaan H. , Meskers Carel G.M. , Harlaar Jaap , Kwakkel Gert
Published: September 2011

Background and Purpose

It is largely unknown how adaptive motor control of the paretic upper limb contributes to functional recovery after stroke. This paucity of knowledge emphasizes the need for longitudinal 3-dimensional (3D) kinematic studies with frequent measurements to establish changes in coordination after stroke. A portable 3D kinematic setup would facilitate the frequent follow-up of people poststroke. This case report shows how longitudinal kinematic changes of the upper limb can be measured at a patient's home using a portable 3D kinematic system in the first 6 months poststroke.

Case Description

The outcomes of the upper-limb section of the Fugl-Meyer Motor Assessment (FMA), the Action Research Arm Test (ARAT), and 3D kinematic analyses were obtained from a 41-year-old man with a left hemispheric stroke. Three-dimensional kinematic data of the paretic upper limb were collected during a reach-to-grasp task using a portable motion tracker in 5 measurements during the first 6 months after stroke. Data from an individual who was healthy were used for comparison.

Outcomes

The FMA and ARAT scores showed nonlinear recovery profiles, accompanied by significant changes in kinematic outcomes over time poststroke. Specifically, elbow extension increased, forward trunk motion decreased, peak hand speed increased, peak hand opening increased, and peak hand opening occurred sooner after peak hand speed.

Discussion

This case report illustrates the feasibility of frequently repeated, on-site 3D kinematic measurements of the paretic upper limb. Early after stroke, task performance was mainly driven by adaptive motor control, whereas adaptations were mostly reduced at 26 weeks poststroke. The presented approach allows the investigation of what is changing in coordination and how these changes are related to the nonlinear pattern of improvements in body functions and activities after stroke.
Management of Sternal Precautions Following Median Sternotomy by Physical Therapists in Australia: A Web-Based Survey
Authors: Tuyl Lara J. , Mackney Jennifer H. , Johnston Catherine L.
Published: September 2011

Background

Sternal precautions are utilized within many hospitals with the aim of preventing the occurrence of sternal complications (eg, infection, wound breakdown) following midline sternotomy. The evidence base for sternal precaution protocols, however, has been questioned due to a paucity of research, unknown effect on patient outcomes, and possible discrepancies in pattern of use among institutions.

Objective

The objective of this study was to investigate and document the use of sternal precautions by physical therapists in the treatment of patients following median sternotomy in hospitals throughout Australia, from immediately postsurgery to discharge from the hospital.

Design

A cross-sectional, observational design was used. An anonymous, Web-based survey was custom designed for use in the study.

Methods

The questionnaire was content validated, and the online functionality was assessed. The senior cardiothoracic physical therapist from each hospital identified as currently performing cardiothoracic surgery (N=51) was invited to participate.

Results

The response rate was 58.8% (n=30). Both public (n=18) and private (n=12) hospitals in all states of Australia were represented. Management protocols reported by participants included wound support (n=22), restrictions on lifting and transfers (n=23), and restrictions on mobility aid use (n=15). Factors influencing clinical practice most commonly included “workplace practices/protocols” (n=27) and “clinical experience” (n=22).

Limitations

The study may be limited by response bias.

Conclusions

Significant variation exists in the sternal precautions and protocols used in the treatment of patients following median sternotomy in Australian hospitals. Further research is needed to investigate whether the restrictions and precautions used are necessary and whether protocols have an impact on patient outcomes, including rates of recovery and length of stay.
A collective portrait of Greek industrialists
Authors: Agriantoni Christine
Published: September 2011

Résumé La discussion sur la place de l’industrie dans la société grecque, ses dimensions et son rôle dans le développement de l’économie grecque au cours des 150 dernières années est souvent dominée par le syndrome de la comparaison avec le modèle des « pays pionniers », ce qui tend à sous-estimer, voire à nier, les réalités de l’industrialisation du pays – retardée, faible, tortueuse, dépendante (à votre guise), mais bien réelle – et à assigner des responsabilités de nature éthique à ses entrepreneurs. Dans une première partie, l’article cherche à présenter les principaux problèmes définissant la nature et le rythme de l’industrialisation de la Grèce et dans une seconde à caractériser le type de capacités entrepreneuriales qui s’est développé dans le secteur industriel de l’économie.
When the history of merchant houses met business history: a comparative historiographical approach
Authors: Chatziioannou Maria Christina
Published: September 2011

Résumé Cet article développe une approche comparatiste qui se centre sur les similitudes et les différences entre les firmes marchandes des Balkans et de la Méditerranée d’une part et celles des États-Unis au XVIII e et au début du XIX e siècle en reprenant les interprétations de l’historiographie. Il part de l’étude des maisons des marchands grecs. Les marchands formaient une grande partie des individus et groupes qui étaient économiquement actifs dans les deux aires examinées. Ils offrent à l’histoire économique comme à l’histoire des entreprises un terrain commun pour analyser l’émergence du capitalisme et de l’organisation en société anonyme. Si les travaux successifs les ont souvent considérés sous des angles différents – comme des porteurs de l’idée nationale, comme des agents du capitalisme marchand, comme des prédécesseurs de la grande entreprise –, les riches archives de leurs maisons offrent aussi les bases d’enquêtes d’histoire culturelle et d’études biographiques de leurs trajectoires mondiales.
Sahara de tous les enjeux
Authors: Bourgeot André
Published: September 2011

Qu’est devenu le Sahara depuis les limes romains, des voyageurs arabes aux dynasties almoravide et almorade conquérantes, en passant par la période coloniale, sans oublier le temps fort de l’indépendance avec l’OCRS (Organisation commune des régions sahariennes) ? Cette mise en perspective du Sahara s’attachera à appréhender quatre thèmes contextualisés. D’abord, la militarisation (américanisation ?) à l’issue des événements du 11 septembre 2001 qui généra la lutte mondiale contre le terrorisme. Elle s’exerça au Sahara dès le mois de septembre 2002. Puis, une analyse traitera de l’immigration clandestine, de son organisation et de l’utilisation des « migrants-marchandises » qui enrichissent bon nombre d’intermédiaires. Ensuite, un état des lieux relatif aux jihadistes d’AQMI permettra de présenter les processus de sanctuarisation dans le septentrion malien et les activités criminelles de ces groupes armés. Enfin, une attention particulière sera accordée à la guerre civile en Libye assortie d’hypothèses sur son évolution et ses conséquences dans l’ensemble de la sous-région.
Les nouveaux enjeux pétroliers de la zone saharienne
Authors: Augé Benjamin
Published: September 2011

Le Sahara est l’une des dernières régions d’Afrique à être encore sous-explorée par les sociétés pétrolières. Cependant, depuis que les cours du brut se sont envolés, il y a une dizaine d’années, l’enclavement, principal obstacle de la région, a pu être surmonté grâce à l’accroissement exponentiel des budgets d’exploration. De plus, l’arrivée de sociétés étatiques, en particulier venant de Chine, a fait passer la rentabilité immédiate après la nécessité absolue de mettre au jour de nouvelles réserves. Cependant, l’étude des cas mauritanien, malien, nigérien et tchadien montre bien combien les situations sont différentes. Certains produisent déjà, comme la Mauritanie (en petite quantité) et le Tchad (le seul exportateur net de la région), tandis que le Niger produira dès 2012 et le Mali, par une sélection hasardeuse des compagnies, n’a pas vu un seul forage depuis des décennies. Ces quatre États se caractérisent aussi par leur absence totale de coopération dans ce domaine pétrolier. Cela serait pourtant nécessaire dans une zone si particulière en termes de climat, de géographie et de sécurité (AQMI et Touaregs).
Niger : un État à forte teneur en uranium
Authors: Grégoire Emmanuel
Published: September 2011

Pays pauvre, le Niger espère connaître un second boom de l’uranium. La course aux matières premières à laquelle se livrent les pays du Nord et les pays émergents lui a permis d’engranger des recettes financières importantes. De plus, cette compétition a instauré un climat de concurrence marqué par une redistribution géopolitique et économique des cartes, qui s’est traduite par la fin du monopole de la France sur ses exportations de yellow cake (concentré d’uranium) : l’hégémonie du groupe Areva a été battue en brèche par l’arrivée de sociétés chinoises qui convoitent les richesses minières et pétrolières de l’Afrique indispensables au développement de leur pays. Pour comprendre les nouveaux enjeux et les rapports de force dont l’uranium du Niger est désormais l’objet, l’article analyse l’impact de son exploitation sur sa vie politique intérieure et étrangère ainsi que sur son économie. En conclusion, il s’interroge sur les conséquences pour le Niger de l’accident survenu à la centrale nucléaire de Fukushima.
Low Cost Implementation of Remote Lab with Large Number of Configurations for a BJT Amplifier
Authors: Samuelsen Dag A. H. , Graven Olaf H.
Published: September 2011

This paper demonstrate how to construct an advanced yet low cost remote lab for experiments for an module in analogue electronics at an electrical engineering course at second year bachelor level. The remote lab is designed for running experiments on a normal BJT common emitter amplifier circuit, while maintaining the possibility for the students to use a wide range of different setups. The main reasons for using remote lab are the opportunity to give the students the chance to focus on the theory for the laboratory and not setup problems, in addition the availability of the exercise is 24/7 and not dependent on the opening hours of the physical laboratory.