bluuebunny/crossref_metadata_2025 huggingface dataset:
Pipeline Coating Selection Process: A Hybrid Multi-Criteria Based Approach
Authors: Hassanien Sherif , Krissa Len , Vorontsov Vitaly
Published: December 2014

The most critical component of external corrosion prevention on pipeline is the protective coating system. The coating selection process can be extremely challenging due to the sheer number of manufacturers and products/options that are offered — often with limited performance data available. Relying solely on manufacturer’s recommendations or information can be problematic when the anticipated service environment has not been adequately characterized, application parameters not completely understood, and/or when there is a misunderstanding of the product’s capabilities. Although there are many test methods for evaluation of pipe coatings, there are no commonly accepted test protocols or acceptance criteria for selecting coatings. Moreover, laboratory based testing is often complicated, expensive, and rarely provides an accurate simulation of field conditions. Although in-house subject matter experts (SMEs) and/or independent coating specialists provide some confidence in coating selection, the diversity of background and experience between these experts frequently creates inconsistency in coating evaluations and can produce divergent or conflicting recommendations.

In this paper, an innovative approach is proposed to address these coating selection process challenges. The proposed approach incorporates a systematic analysis of critical material attributes within an expert environment, and applies established decision making techniques to the evaluation. Priorities are developed by structuring a hierarchy of criteria and eliciting technical judgment of company’s SMEs, stakeholders, and unbiased industry specialists. The Deterministic Analytic Hierarchy Process (d-AHP) is applied using pairwise comparisons for prioritizing coating products/options and achieving an optimal selection. The experts’ opinions can then be updated by technical lab-based results for a smaller selection of top ranked products. Laboratory tests would be expected to be completed annually based on smart selection of certain products and to ensure year-over-year consistency. This paper also presents a probabilistic approach that improves d-AHP in order to capture uncertainties in experts’ opinions and/or lab results through probabilistic AHP (p-AHP). Although this approach is not widely used within the pipeline industry, there is a potential opportunity to improve conventional approaches for selecting and approving coatings for pipelines based on a systematic/quantitative approach.
Use of Discrete Element Modeling to Capture the Effect of Backfill Particle Size on the Soil Restraints of Buried Pipelines Subjected to Lateral Ground Movement
Authors: Dilrukshi Sadana , Wijewickreme Dharma
Published: December 2014

Geotechnical hazards can be a major cause of damage to pipelines, particularly as a result of unacceptable strains induced in buried pipelines due to permanent ground deformations. The common design philosophy in reducing soil restraint involves taking measures to effectively isolate the pipeline from the anticipated surrounding soil movements. One of the important engineering design considerations in this regard is the selection of suitable trench backfill material(s). Full-scale model tests have revealed that, in addition to the internal friction angle, coarseness of the backfill material is also an important parameter in controlling the lateral soil restraints on the pipes due to ground movements. It can be demonstrated that discrete element approach is suitable to study the effect of particle size on lateral soil loads of buried pipelines subjected to ground movement. This paper describes the outcome from DEM numerical modeling of the response of buried pipelines subjected to lateral ground movements, with a comparison of the findings with experimental results.
Effects of Microstructural Inhomogeneity on HIC Susceptibility and HIC Evaluation Methods for Linepipe Steels for Sour Service
Authors: Kim Kyu Tae , Ko Sang Gi , Han Jong Man
Published: December 2014

It has been well documented that slab internal quality is one of the key factors for reduced susceptibility of hydrogen induced cracking (HIC) in line pipe steels designed for sour gas service. In addition, the creation of a homogeneous microstructure which is heavily influenced by the slab internal quality is also a critical key parameter to reduce the HIC susceptibility in higher strength line pipe steel grade X60 and above. For the application of deep sea linepipe exposed to higher external pressure environments, heavy gauge in combination with higher strength steel is essential. Homogeneity of the steel microstructure is a key to success for thicker plates used in sour service HIC applications in combination with a deep sea environment.

In this paper, various microstructures were compared along with an evaluation of the effects of the various microstructures on HIC susceptibility in grades X52, X65 and X70 designed for sour service. The various microstructures compared consisted of polygonal ferrite and pearlite in the X52 and polygonal ferrite, pearlite, acicular ferrite and bainite in the X65 and X70. The effect of microstructural inhomogeneity on HIC susceptibility was comparatively lower for the X52 than that of the X65 and X70. The microstructure of grade X65 and X70 were different due to the different conditions of rolling and cooling that were applied. Grades X65/X70 had a microstructure of polygonal ferrite/pearlite with bainite islands that resulted in a high crack length ratio (CLR) value caused by different hardness regions across the microstructural matrix. A homogeneous fine acicular ferrite microstructure produced by optimizing temperature control during rolling and cooling showed no hydrogen induced cracking. In addition, this alloy/process/microstructure design resulted in improved toughness results in low temperature drop weight tear test (DWTT). This paper will describe the successful production results of plate and pipe for high strength heavier gauge line pipe steels with highly homogeneous microstructures designed for sour service by controlling chemical design and process conditions in rolling and cooling.

In addition, HIC evaluation methods utilizing both a traditional NACE TM0284 method versus that of a Scan-UT method were conducted and compared. A proposal to make the NACE TM0284 testing method more reliable by using Scan-UT method will be presented.
External Pipeline Leak Detection Based on Fiber Optic Sensing for the Kinosis 12″–16″ and 16″–20″ Pipe-in-Pipe System
Authors: Borda Carlos , DuToit Dana , Duncan Harry , Niklès Marc
Published: December 2014

The concern of the pipeline industry and general population for a safe and green environment is higher than ever. This highlights the need for efficient leak detection to prevent environmental catastrophes and operational disruption. Therefore, accurate techniques to detect and locate very small leaks that could develop into larger leaks are a valuable asset for the construction of key pipelines. External pipeline leak detection systems based on distributed fiber optic sensing emerge as the most appropriate solution for automatic detection and localization of very small leaks.

In the case of the Kinosis pipeline system, two 11km Electrically Heat Traced Pipe-In-Pipe (EHTPIP) pipelines have been built between the Nexen Long lake upgrader and Nexen Kinosis SAGD facilities. The fiber optic sensing cable is directly in contact with the EHTPIP external surface. These pipelines carry Produced Emulsion and Boiler Feed Water at temperatures as high as 120°C and 150°C respectively. The fiber optic distributed sensing system provides temperature feedback information to the operator, not only in operation and in case of a leak but also when the Electrical Heat Trace system is turned on; in this case, the monitoring system can detect and locate overheating problems and/or signs of heating failures.

In the case of a leak, the outer temperature of the pipeline will increase; this will automatically be detected and monitored by the DITEST temperature monitoring system and will trigger an alarm to the Nexen LONG LAKE upgrader SCADA system for that specific location.

Furthermore, the combination of fiber optic distributed monitoring with the PIP technology enables to detect and locate a leak in the inner pipeline at a very early stage, therefore avoiding any environmental damage (the leak is still contained by the outer PIP tube) and giving time to the pipeline operator to plan a sectional replacement.
The Essential Welding Variable Approach and its Application to the Welding of X80 Line Pipe Steels
Authors: Chen Yaoshan , Gianetto Jim , Fazeli Fateh , Sui Yongli , Jin Haicheng
Published: December 2014

A weld quality control approach developed for the welding of high-strength pipeline steels has demonstrated its effectiveness in achieving reliability and consistency in the mechanical performance of girth welds. Using a predictive tool that can relate cooling times of welding thermal cycles with welding parameters and with the knowledge of microstructure responses of both pipe materials and weld metals to welding thermal cycles, the approach can evaluate the effects of welding parameters on weld properties and identify the essential welding variables. As a result, the essential welding variable approach can be used to optimize and help shorten the process of welding procedure development.

The current paper presents the application of the essential welding variable approach to the girth welding of X80 pipeline steels.

The application started with the selection of pipe materials, welding consumables, and candidate welding procedures. The selection of actual weld procedures and a welding matrix were made after the candidate welding procedures were analyzed in terms of cooling times. Girth welds for two X80 pipes of different chemical compositions, outside diameters, and wall thicknesses were made with single and dual torch GMAW-P processes and a range of welding consumables. The welding parameters were monitored and recorded for all welds; and the thermal cycles of selected welds were measured by thermocouples.

Small-scale testing, including all-weld-metal tensile test, Charpy impact toughness and CTOD fracture toughness tests, were evaluated and correlated with microstructures formed in the HAZ of the girth welds. The material responses of heat-affected zone (HAZ) to thermal cycles of typical GMAW-P single and dual torch processes were experimentally simulated (Gleeble®).

Detailed welding thermal cycle analyses were conducted based on the measured welding parameters. Cooling times of welding thermal cycles for the girth welds were calculated and correlated with the material responses, of X80 pipe steels to welding thermal cycles. The correlation demonstrated very good consistency between the cooling times, the results of the Gleeble simulation, and the mechanical properties of the girth welds.

The dependency of the weld properties on welding parameters was analyzed in terms of cooling times, and the optimization strategy for development of welding procedures that offer more balanced welding properties between strength and toughness was evaluated by adjusting the essential welding variables.

In summary, the process of applying the essential welding variable approach and the results from the tests and the analyses showed that the approach is capable of evaluating the effects of welding parameters on weld properties, identifying the essential welding variables, and ultimately optimizing welding procedures.
Application of Probabilistic Methods for Predicting the Remaining Life of Offshore Pipelines
Authors: Aljaroudi Alireda , Thodi Premkumar , Akinturk Ayhan , Khan Faisal , Paulin Mike
Published: December 2014

When offshore pipelines are approaching the end of their design life or have gone beyond their design life, their condition could possibly threaten oil flow continuity (through leak or rupture) as well as become a potential safety or environmental hazard. Some of the pipelines may show signs of deterioration and ageing due to corrosion, cracking or other damage mechanisms. Any assets, such as the pipeline, may be desired to continue transporting hydrocarbons beyond its design life due to increased oil and gas demand, due to unforeseen increased oil and gas reserves, or due to upgrade where additional assets are tied-into the existing pipeline system. Other situations may force operators to maintain the pipeline’s design life in spite of premature ageing of the pipe wall caused by the increased corrosion growth or other anomalies. Hence, there may be a need to assess the remaining life of pipeline in order to determine if it is capable of coping with current and future operational demand. The first task in the assessment process is to identify degradation mechanisms and their rate of growth, then estimate uncertainties in the collected data concerning pipeline flaw geometry, pipeline mechanical properties and operating characteristics. Based on the collected data and the assessment, the probability and consequence of failure can be determined. The remaining life of a pipeline is the time it takes the pipeline to fail or exceed the target failure probability. This paper presents a methodology for assessing the condition of ageing pipelines and determining the remaining life that supports extended operation without compromising safety and reliability. Applying this methodology would facilitate a well-informed decision that enables decision makers to determine the best strategy or adequate course of action for assessing and maintaining the integrity of ageing pipelines.
A Novel Approach for Pipe Grade Determination Through In-Line Inspection (ILI)
Authors: Molenda Daniel , Thale Werner
Published: December 2014

When establishing a pipelines’ maximum allowable operating pressure (MAOP), many pipeline operators face uncertainties regarding the yield strength of the respective pipeline material. This specifically concerns “pre-regulatory” pipelines which, for example, constitute approximately 66% of all gas transmission pipelines in the U.S. as well as new pipelines to ensure laid steel pipes meet the contracted steel grade.

Conventional ILI technologies are capable of delivering relevant information for MAOP calculation, such as wall thickness and diameter. However, as missing element, in the past there have been no economic means for accurately measuring yield strength. Therefore ROSEN has developed and tested a novel ILI system for measuring yield strength of pipeline steel.

This paper introduces the fundamental principles of this new system and outlines first results.

Laboratory test results are obtained from samples covering the typical range of pipeline steels. The sensor readings are correlated with reference yield strengths of certified steels where the yield strength was determined by destructive tensile tests.

Initial pull tests with an ILI tool measurement are compared with the available yield strengths and tensile strengths according to the inspection certificates of the pull test pipes.
Achievements of the Professional Qualification Program in Transpetro
Authors: Tomaz Luciane Gonçalves , Real Vicente José Campitelli
Published: December 2014

The Professional Qualification Program in Natural Gas Transmission (PQGN, in the Portuguese initials) was created in 2009 and started implementation in 2010 with the goal of training all technicians with less than three years’ experience at Transpetro and focusing on specific activities related to the transportation of natural gas to guarantee safety and operational continuity. It was developed with internal instructors to facilitate the sharing of technology between experienced technicians and those less experienced. Since its inception, the program has undergone many improvements and critical analysis. Today, the PQGN has five modules: fundamentals, pipeline maintenance, right-of-way maintenance, maintenance and local operations at compression stations and maintenance management. All courses have been developed based on the mapping of activities and tasks of the technicians. Critical tasks and activities have also been listed to develop the training program. The program has been extended to the experienced technicians in order to meet the minimum requirements of the Pipeline Technical Regulation published by the ANP [2] (National Petroleum, Natural Gas and Biofuels Agency) in February 2011. This paper shows how the work was done and what was done in this period as well as some results of the project implementation.
Validation of EMAT ILI for Management of Stress Corrosion Cracking in Natural Gas Pipelines
Authors: Fore Toby , Klein Stefan , Yoxall Chris , Cone Stan
Published: December 2014

Managing the threat of Stress Corrosion Cracking (SCC) in natural gas pipelines continues to be an area of focus for many operating companies with potentially susceptible pipelines. This paper describes the validation process of the high-resolution Electro-Magnetic Acoustical Transducer (EMAT) In-Line Inspection (ILI) technology for detection of SCC prior to scheduled pressure tests of inspected line pipe valve sections. The validation of the EMAT technology covered the application of high-resolution EMAT ILI and determining the Probability Of Detection (POD) and Identification (POI). The ILI verification process is in accordance to a API 1163 Level 3 validation. It is described in detail for 30″ and 36″ pipeline segments. Both segments are known to have an SCC history. Correlation of EMAT ILI calls to manual non-destructive measurements and destructively tested SCC samples lead to a comprehensive understanding of the capabilities of the EMAT technology and the associated process for managing the SCC threat. Based on the data gathered, the dimensional tool tolerances in terms of length and depth are derived.
An Engineering Assessment to Evaluate Integrity Options for Out of Class Pipelines
Authors: Wang Hong , Kariyawasam Shahani , Kwong Pauline
Published: December 2014

As population growth and development occurs along the pipeline right of way, the class location of pipeline segments could change to a higher class designation. A higher location class designation has a more stringent location factor according to Canadian Standard Association (CSA) Z662-11 Clause 4.3.7. For this situation, Onshore Pipeline Regulations (OPR) s.42 requires pipeline operators to submit a proposed plan in conformance with CSA Z662 requirements in Clause 10.7. Typically for compliance, a change to higher class designation leads to pipe replacement or operating pressure reduction (compliance options). Alternatively, the pipeline segment could also be subjected to an engineering assessment (EA) to develop other measures which are as safe as or safer than the compliance options.

The CSA code requirements of pipeline replacement or pressure reduction for out-of-class pipe cater to generic cases, and essentially make the out-of-class pipe segment comply such that it is within class. In contrast, a site-specific EA considers the actual pipe conditions, the relevant hazards, and the case specific solutions. Therefore, the site-specific EA provides a more appropriate solution for the problem at hand and ensures a risk consistent approach for the class change site. This also provides a safety level that is equivalent or above the regulatory requirements.

A three-level engineering assessment methodology was developed for an out-of-class EA. In the first level assessment, the design, construction, testing procedures and the location class development are reviewed to understand the regulatory constraints and compliance aspects. In the second level assessment, all the potential hazards are identified and assessed to determine the pipeline condition. Finally, in the third level assessment, quantitative reliability assessment techniques were utilized to determine the optimized mitigation activities that can make the pipe segments as safe as or safer than the compliant options.

The class change EA used the above methodology to quantitatively compare mitigation activities with pipe replacement and reduced operating pressure scenarios. Some mitigation activities provided greater safety than pipe replacement and reduced operating pressure scenarios, thus providing safer options while avoiding pipeline service interruption; minimizing in-field disturbances and related risks of replacement; and providing cost-benefit optimization. The growth of urban areas and related encroachment on pipeline corridors is a common occurrence. Therefore this EA approach has industry wide applications in providing safer and more optimized solutions.
“I Know It When I See It”: Where to Look for Social License
Authors: Douglas Garrath
Published: December 2014

It has become axiomatic that a social license is a critical success factor for Canadian pipelines. Regulators may permit a pipeline, but on-the-ground consent for a project is a function of communities. Social license is an intangible quality outside of formal regulation, occupying the gap between community expectations and existing laws.

Increasingly, gaining social license is seen as an important aspect of managing environmental and social risks, and the presence or absence of social license affects project budgets, timelines, corporate reputation and even project outcomes. There are regulatory risks to not demonstrating social license; and even with regulatory approval social license may be the difference between legal challenges and none.

Social license is not easy to find, is difficult to measure, and is capricious and dynamic in nature. It is an inherently vague and changeable standard that means different things to different people. Simply defining social license can be a futile enterprise: as with US Supreme Court Justice Stewart’s famous 1964 judgment, we can’t neatly define social license, but we know it when we see it.

The emergence of social media has meant that communities are better engaged, informed, and networked than ever before. Gaining social license happens when trust is built, earned and maintained with communities: it can take a long time to build that trust, and today’s digital citizen expects engagement across many platforms in order for that trust to be maintained.

Though there is no ‘one-size-fits-all’ approach to gaining social license, the approach of this paper is to lay out a case-study roadmap for navigating towards it by building relationships, countering misinformation, and mobilizing existing support. The paper will also recognize potential wrong turns such as inattention to social media, lack of transparency or a clear message, and the mistaken belief that regulatory approval is the only approval necessary.
Quantifying the Impact of Assumptions on Predicted Burst Pressure Assessments
Authors: Polasik Steven J. , Keane Sean , Harper William V. , Bubenik Tom
Published: December 2014

The ability for deterministic fracture mechanics assessments to correctly estimate the predicted burst pressure (PBP) is dependent upon the accuracy of the model as well as the assumptions made regarding mechanical properties and defect geometry. Within the assessment of defects identified through field investigation or through ILI programs, the use of extreme bounding values for all input variables can lead to unacceptably over-conservative predictions and impede the ability to achieve a target safety margin.

This paper examines the effect multiple assumptions have on the bias between predicted and actual burst pressures for various kinds of defects that have caused in-service and hydrostatic pressure test failures in ERW and flash weld line pipe materials. The predicted failure pressures of defects documented within a recent U.S. Department of Transportation compendium of ERW and flash weld seam failures were analyzed using a variety of scenarios based on knowledge of key nominal parameters such as grade, outside diameter, wall thickness, and the maximum defect length and depth. The ratio of the predicted to actual failure pressure was statistically examined across the scenarios for the different defect types. Observations are made regarding the use of the PBP model in order to statistically quantify the accuracy of the model, which can be used as input for an operator to develop a process that achieves a target safety margin.
A Novel Approach to Evaluating Leak Detection CPM System Sensitivity/Reliability Performance Trade-Offs
Authors: Chadha Shyam , Hung Daniel , Rashid Samir
Published: December 2014

As defined in American Petroleum Institute Recommended Practice 1130 (API RP 1130), CPM system leak detection performance is evaluated on the basis of four distinct but interrelated metrics: sensitivity, reliability, accuracy and robustness. These performance metrics are captured to evaluate performance, manage risk and prioritize mitigation efforts.

Evaluating and quantifying sensitivity performance of a CPM system is paramount to ensure the performance of the CPM system is acceptable based on a company’s risk profile for detecting leaks. Employing API RP 1130 recommended testing methodologies including parameter manipulation techniques, software simulated leak tests and/or removal of test quantities of commodity from the pipeline are excellent approaches to understanding the leak sensitivity metric.

Good reliability (false alarm) performance is critical to ensure that control center operator desensitization does not occur through long term exposure to false alarms. Continuous tracking and analyzing of root causes of leak alarms ensures that the effects of seasonal variations or changes to operation on CPM system performance are managed appropriately. The complexity of quantifying this metric includes qualitatively evaluating the relevance of false alarms.

The interrelated nature of the above performance metrics imposes conflicting requirements and results in inherent trade-offs. Optimizing the trade-off between reliability and sensitivity involves identifying the point that thresholds must be set to obtain a balance of a desired sensitivity and false alarm rate.

This paper presents an approach to illustrate the combined sensitivity/reliability performance for an example pipeline. The paper discusses considerations addressed while determining the methodology such as stakeholder input, ongoing CPM system enhancements, sensitivity/reliability trade-off, risk based capital investment and graphing techniques. The paper also elaborates on a number of identified benefits of the selected overall methodology.
Multi-Satellite InSAR Deformation Analysis for Pipeline Monitoring: Operational Application, Results and Validation in the Belridge Oil Field, 2001–2012
Authors: Henschel Michael D. , Deschamps Benjamin , Robert Gillian , Gailing Rick
Published: December 2014

This paper presents a time history of 12 years of surface deformation in the Belridge Oil Field, California, USA from an InSAR analysis using multiple satellites.

The time series reveals deformation rates as high as 80 cm/yr at times with a maximum overall deformation of 3.92 m. The use of multiple satellites and multiple observation modes provided deformation measurements at a frequency as high as every two days from the RADARSAT-1 and RADARSAT-2 satellites.

The InSAR derived estimates of motion are shown with respect to a pipeline segment that transects the Belridge Oil Field. The use of wide area ground movement monitoring provides both high resolution (3 m on the ground) and high precision (deformation measurements to ± 1 mm).

The observed ground motion is validated with collocated measurements from a set of Global Navigation Satellite System units installed for a period in 2012.

The long term, validated time series of observations provide a unique data set with which to compare pipeline incidents. The correlation between incidents and ground movement can help estimate the pipeline state as related to stress and strain from ground displacement.
Effective Improvements to Overcome “Blind Spots” in a Corrosion Management Program and Practical Measures to Verify Effectiveness
Authors: Huang Terry , Kariyawasam Shahani , Yeung Patrick , Shariq Mohammad
Published: December 2014

The recent industry wide post-ILI pipeline ruptures due to external corrosion happened in a relatively short period of time after the ILI using high-resolution Magnetic Flux Leakage (MFL) technology. Failure investigations show that the critical defects that caused these pipeline ruptures are generally long and complex corrosion, which typically consist of a number of deep corrosion pits (i.e. localized metal-loss) within an overall shallower, but relatively large corrosion area (i.e. generalized metal-loss). This has led us to investigate the gaps and “blind spots” of the ILI-based corrosion management program particularly to find out why existing methods fail to effectively identify and remediate such critical defects before they fail. Learning from these post-ILI failures, TransCanada has developed many assessment methods and criteria for identifying challenging areas. The many types of criteria account for blind spots from different perspectives in a multi-faceted manner.

The traditional ILI based corrosion management programs calculate a deterministic failure pressure ratio (FPR) and maximum anomaly depth and ensure these do not reach a limiting value. However, this strictly deterministic assessment does not acknowledge the uncertainties, particularly the significant uncertainties in the ILI measurements, assessment models, and material properties. When all uncertainties are accounted for and a probabilistic excavation criterion is used, the excavations reveal that certain anomalies are found to be near-critical in the field even though the deterministic FPR based criteria did not identify these. The probabilistic criteria identifies longer shallower anomalies, with non-critical ILI based FPR values, as anomalies that have a higher probability of exceeding the FPR criteria in-the-ditch (where the uncertainties are minimized). This is because the probabilistic criterion acknowledges that longer anomalies are more sensitive to the depth measurement error and have a higher probability of becoming critical in-the-ditch. This “blind spot” in the deterministic method was overcome by incorporating a probabilistic criterion into the corrosion management program.

The effectiveness of these new measures is discussed by examining excavation results of this program and subsequent ILI results. This paper discusses the approach to corrosion management where new learning and knowledge as well as new-found uncertainties are readily accommodated. The approach is also transparent and documented; so that new information can be incorporated into the assessment and post-ILI failures can be prevented more effectively.
Best Practices for Yield Stress Determination Using the Flattened Strap Tensile Test
Authors: Collins L. E. , Rashid M.
Published: December 2014

The tensile properties of line pipe are usually determined using a flattened strap tensile sample which is obtained by cutting a long transverse sample from the pipe and then flattening it prior to machining the final tensile coupon. Although, several documents have been published to standardize this test, variability in the reported yield stress for the same material tested by different labs continues to be an issue particularly in high strength line pipe (X70 and X80).

Pipe properties are influenced by the pipe forming operations which introduce plastic strain into the steel. As well, the flattening of the tensile blank reverses the deformation and leads to Bauchinger effects which further alter the tensile properties of the material. There is no standard available for the flattening process and pipe manufacturers and operators continue to seek a best practice for the process. In addition, other factors such as placement of extensometer on a flattenend tensile specimen during the tensile testing have been considered a source of variation in the results.

Several projects were conducted to identify the source of variability and to standardize the flattening and testing process among the Evraz QA Labs. These initiatives included: a round robin tensile testing program in which tensile tests were performed on flat plates and subsequently on flattened strap specimens produced from a sister plate; examination of a 2-step flattening procedure against a 1-step method, and investigation of the extensometer placement (ID, OD or side mounted) on the recorded stress-strain behaviour.

The flattening process was found to be the main source of variability of yield stress. No real trend was observed resulting from extensometer position. Other testing practices such as specimen gripping, zeroing the load and positioning at the start of the test, and the dimensional variability within the reduced section of a specimen were also found to contribute to yield stress variability. Best practices for determination of yield stress using flattened strap tensile samples are discussed.
Failure Analysis of 12 Inch Pipeline Riser
Authors: Gareau Frank , Tatarov Alex
Published: December 2014

A rupture and an explosion occurred on a 12.75 inch OD high pressure gas pipeline after 40 years in service. The force of the explosion broke the riser off and sent two large pieces of the riser flying into the surrounding forest.

The failure occurred as a result of the simultaneous action of several contributing factors:

• The weld had a non-specified profile (a step) and contained a large slag inclusion at the location of fracture initiation.

• Corrosion pits were growing from the internal surface close to the weld root.

• Dewpoint corrosion took place on the internal surface of the riser close to massive flanges.

• The dehydrator at the compressor station was not removing the target amount of moisture.

• Low temperatures contributed to the failure by decreasing material fracture toughness.

• Ground movement could have created additional stress required for the failure to occur.

Several of the above listed factors (pitting corrosion, ground movement, malfunctioning of the dehydrator) developed with time, which explains the delayed mode of failure.

The conclusions were supported by Finite Element Analysis and Fracture Mechanics calculations.
Why Marine Mammals Matter to Your Terrestrial Export Pipeline Project
Authors: Ahrens Andrea , Green Jeffrey , Anderson Paul , Postlewaite Linda
Published: December 2014

Increases in export pipeline development can result in a corresponding increase in marine transportation activities and the potential to escalate adverse interactions with marine wildlife. Ship traffic introduces risks of vessel strikes as well as the amount of underwater noise produced in the marine environment. Growing public and scientific concern over the potential effects of increasing ship traffic on marine wildlife mean that even terrestrially-based pipeline projects need to start considering the effects of shipping in developing environmental mitigation programs for their export operations. Northern Gateway is proposing to construct and operate twin pipelines between Alberta and British Columbia, and an associated tank and marine terminal for export operations. While Northern Gateway will not own or operate any of the tankers, they have committed to implementing a comprehensive marine mitigation, monitoring and research program, including measures to reduce ship strikes and effects of underwater noise on marine mammals. Vessel strikes can cause severe or fatal injuries. Higher relative risk exists where shipping traffic overlaps with increased densities of marine mammals. Vessel speed has been positively correlated with the degree of risk and injury; consequently, Northern Gateway has set maximum year-round speed restrictions of 10–12 knots for all Project-related tankers calling at the marine terminal, with further restrictions of 8–10 knots in key areas. Other large vessels in this region currently travel at speeds of 16–21 knots. Mandatory speed restrictions will also reduce the Project’s contribution to underwater noise. Effects of underwater noise on marine mammals include temporary habitat avoidance, reduced feeding efficiency, behavioural change, increased stress, and communication masking. Acoustic modeling conducted for the project predicted that reducing vessel speeds from 15 to 9.6 knots would decrease underwater noise input by nearly 12 dB, making the zone of ensonification 2–3 times smaller than in the absence of mitigations. Purpose-built escort tugs will use best commercially-available noise-quieting technology and speed restriction areas will be refined through six-years of surveys and a quantitative vessel strike analysis. Vessel traffic is not unique to Northern Gateway; however, through minimizing their incremental contribution, they hope to serve as an industry example. This approach to minimizing effects of routine marine export operations is unique in the shipping industry in Canada and the United States. If other proponents were to adopt similar types of measures, Northern Gateway believes that the marine environment would see some net benefits in terms of a reduction in adverse effects on marine mammals.
Quantifying Fundamental Movement Skills During Active Video Games
Authors: Thornton Ashleigh , Lay Brendan , Rosenberg Michael , Granich Joanna , Braham Rebecca
Published: December 2014

This study sought to explore the type of fundamental movement skills (FMS) performed during Active Video Game (AVG) play, as well as the frequency with which these FMS are performed. In addition, this study aimed to determine the relationship between FMS performance and energy expenditure during 15 min of AVG play across two Microsoft Xbox Kinect AVGs. Fundamental movement skills were observed via video by two raters and energy expenditure derived using Actiheart monitors in children aged 10–15 years. Six different FMS were observed during AVG play with differences in the number of FMS performed between the two AVGs. The overall energy expended (Joules/kg/minute), however, was similar between the AVGs, suggesting the frequency of FMS did not influence overall energy expended during play. The movements observed during AVG play that possibly accounted for the energy expenditure, were not of a quality that could be classified as FMS. This research demonstrates that children playing these two games have the opportunity to repeatedly perform mostly two FMS, namely jumping and dodging. The goal of the AVGs, however, could be achieved with generalized movements that did not always meet the criteria to be classified as a FMS.
Improving Hybrid FTL by Fully Exploiting Internal SSD Parallelism with Virtual Blocks
Authors: He Dan , Wang Fang , Jiang Hong , Feng Dan , Liu Jing Ning , Tong Wei , Zhang Zheng
Published: December 2014

Compared with either block or page-mapping Flash Translation Layer (FTL), hybrid-mapping FTL for flash Solid State Disks (SSDs), such as Fully Associative Section Translation (FAST), has relatively high space efficiency because of its smaller mapping table than the latter and higher flexibility than the former. As a result, hybrid-mapping FTL has become the most commonly used scheme in SSDs. But the hybrid-mapping FTL incurs a large number of costly full-merge operations. Thus, a critical challenge to hybrid-mapping FTL is how to reduce the cost of full-merge operations and improve partial merge operations and switch operations. In this article, we propose a novel FTL scheme, called Virtual Block-based Parallel FAST (VBP-FAST), that divides flash area into Virtual Blocks (VBlocks) and Physical Blocks (PBlocks) where VBlocks are used to fully exploit channel-level, die-level, and plane-level parallelism of flash. Leveraging these three levels of parallelism, the cost of full merge in VBP-FAST is significantly reduced from that of FAST. In the meantime, VBP-FAST uses PBlocks to retain the advantages of partial merge and switch operations. Our extensive trace-driven simulation results show that VBP-FAST speeds up FAST by a factor of 5.3--8.4 for random workloads and of 1.7 for sequential workloads with channel-level, die-level, and plane-level parallelism of 8, 2, and 2 (i.e., eight channels, two dies, and two planes).
Mucocutaneous Leishmaniasis/HIV Coinfection Presented as a Diffuse Desquamative Rash
Authors: da Silva Guilherme Almeida Rosa , Sugui Daniel , Nunes Rafael Fernandes , de Azevedo Karime , de Azevedo Marcelo , Marques Alexandre , Martins Carlos , Ferry Fernando Raphael de Almeida
Published: December 2014

Leishmaniasis is an infectious disease that is endemic in tropical areas and in the Mediterranean. This condition spreads to 98 countries in four continents, surpassing 12 million infected individuals, with 350 million people at risk of infection. This disease is characterized by a wide spectrum of clinical syndromes, caused by protozoa of the genusLeishmania, with various animal reservoirs, such as rodents, dogs, wolves, foxes, and even humans. Transmission occurs through a vector, a sandfly of the genusLutzomyia. There are three main clinical forms of leishmaniasis: visceral leishmaniasis, cutaneous leishmaniasis, and mucocutaneous leishmaniasis. The wide spectrum of nonvisceral forms includes: localized cutaneous leishmaniasis, a papular lesion that progresses to ulceration with granular base and a large framed board; diffuse cutaneous leishmaniasis; mucocutaneous leishmaniasis, which can cause disfiguring and mutilating injuries of the nasal cavity, pharynx, and larynx. Leishmaniasis/HIV coinfection is considered an emerging problem in several countries, including Brazil, where, despite the growing number of cases, a problem of late diagnosis occurs. Clinically, the cases of leishmaniasis associated with HIV infection may demonstrate unusual aspects, such as extensive and destructive lesions. This study aims to report a case of mucocutaneous leishmaniasis/HIV coinfection with atypical presentation of diffuse desquamative eruption and nasopharyngeal involvement.
Seroprevalence and Seroconversion of Dengue and Implications for Clinical Diagnosis in Amazonian Children
Authors: Martins Antonio Camargo , Pereira Thasciany Moraes , Oliart-Guzmán Humberto , Delfino Breno Matos , Mantovani Saulo Augusto Silva , Braña Athos Muniz , Branco Fernando Luiz Cunha Castelo , Filgueira Júnior José Alcântara , Santos Ana Paula , Ramalho Alanderson Alves , Guimarães Andréia Silva , de Araújo Thiago Santos , Oliveira Cristieli Sérgio de Menezes , da Fonseca Benedito Antônio Lopes , da Silva-Nunes Mônica
Published: December 2014

This study aimed to evaluate the prevalence of serum IgG dengue in children in an Amazonian population, to assess the seroconversion rate in 12 months, and to estimate how many seropositive children had a prior clinical diagnosis of dengue. We conducted a population-based study between 2010 and 2011, with children aged 6 months to 12 years that were living in the urban area of a small town in the Brazilian Amazon. The prevalence of IgG antibodies against dengue antigens was determined by indirect ELISA technique, and seronegative children were reexamined after 12 months to determine seroconversion rates. Results showed seroprevalence of IgG antibodies against dengue type of 2.9%, with no significant association between age, race, and sex. In seropositive children, only 8.4% had received a clinical diagnosis of dengue, and the ratio of clinically diagnosed cases and subclinical cases was 1 : 11. The seroconversion rate between 2010 and 2011 was 1.4% (CI 3.8% to 35.1%). The seroprevalence of dengue in this pediatric population was low, and the vast majority of cases were not clinically detected, suggesting a difficulty in making the clinical diagnosis in children and a high frequency of asymptomatic infections.
Sympathetic Nervous System-Immune Interactions in Autoimmune Lymphoproliferative Diseases
Authors: del Rey Adriana , Besedovsky Hugo O.
Published: December 2014

With some exceptions, the sympathetic nervous system has often been regarded as an immunosuppressive system. However, we know now that the immunoregulatory role of the sympathetic nervous system cannot be described in such absolute terms. Indeed, sympathetic neurotransmitters can inhibit or stimulate an immune response depending on numerous variables, which include the type of adrenergic receptor involved, the kind of antigen that triggers the immune response, and the subset of immune cells affected. A most important consideration is that immune and sympathetic responses are phasic phenomena and the step of the immune response at which lymphoid and/or accessory cells are exposed to neurotransmitters, or deprived from their presence, seems decisive for the outcome. The large amount of basic research on the role that the sympathetic nervous system plays in neuroimmunomodulation has prompted studies on its pathological implications. Systemic lupus erythematosus is an autoimmune lymphoproliferative disease that has mainly been associated with a Th2 shift and increased humoral responses. Lpr/lpr mice, which express a defective Fas, are commonly used as a model of this disease, and more recently, also of the autoimmune lymphoproliferative syndrome. We have found that, besides defects in the Fas pathway, lpr/lpr mice have an altered sympathetic innervation, and that this alteration contributes to the pathogenesis of the disease. The results strongly support the hypothesis that the sympathetic nervous system can modulate the expression of autoimmune lymphoproliferative diseases.
The Transformation of Apologetical Literature in the Early Enlightenment
Authors: Lottes Günther
Published: December 2014

Context and argumentative style of Grotius’s De veritate are that of Reformation controversialist theology and of humanist historical notions of truth. Controversialism, however, no longer operated from shared principles, and the textual criticism of humanist scholarship implied looking at the book of revelation as an historical document, in a double sense: a product of history, and (one among other) historical narratives. To what intellectual juggling this leads Grotius, is evident in his considering the historical proofs of the resurrection of Christ, the role therein of witnesses and of pagan historical support. Justifying Christ’s resurrection with pagan theories of metempsychosis, however, was another step towards a rational justification of Christianity. His defence of a minimalist doctrinal content was not yet deist or neological, as his reliance on miracles and resurrection demonstrate. One thus might locate this text at the ‘false dawn’ of the Enlightenment, as a comparison with Edward Lord Herbert of Cherbury’s homonymous book, abstract and general enough to become a really Deist manifesto, finally shows.
Philippus van Limborch’s Amica Collatio and its Relation to Grotius’s De Veritate
Authors: van Leeuwen Th. Marius
Published: December 2014

This paper deals with the influence of De veritate on Van Limborch’s Amica collatio cum erudito Judaeo (1687), which is often considered as an early example of interfaith dialogue in a tolerant atmosphere. The first section introduces the Remonstrant theologian Van Limborch (1633–1712), with special attention to his relation to Grotius. The second section focuses on the Collatio. Van Limborch’s discussion partner Orobio de Castro (ca. 1620–1687) is introduced. The way in which the dialogue develops is sketched: it starts in a reasonable mode, but towards the end Van Limborch’s tone can hardly be called ‘friendly’ anymore. He cannot accept that a reasonable man does not see the superiority of Jesus, and tries to convert his discussion partner. The third section summarizes the influence of Grotius on the Collatio. Van Limborch learned from him not to argue about dogmatic constructions, but to start from the Bible and its unquestionable revelations. He follows the logic of De veritate, Book II and III, arguing that the truth about Jesus can only be proven from the New Testament, which contains reliable testimonies to him and his miracles. He follows the tenor of Book v as well, arguing that the Jews should look upon the miracles of Jesus as sufficiently attested and greater than those of Moses, and therefore should convert themselves. On closer analysis the Collatio can hardly be considered as an example of interfaith tolerance, neither can Grotius’ De veritate.