Fatigue Monitoring and Life Extension for Top Tensioned Production Riser Systems

2021 ◽  
Author(s):  
Bulent Mercan ◽  
Mike Campbell ◽  
Clay Thompson
Keyword(s):  
Deep Water ◽  
Low Cost ◽  
Monitoring Program ◽  
Field Measurements ◽  
Fatigue Loading ◽  
Life Extension ◽  
Fatigue Monitoring ◽  
One Step ◽  
And Performance ◽  
The Impact

Abstract Top tensioned production riser (TTR) systems are exposed to fatigue loading in deep water as a result of vessel motions and high currents. The accuracy of predictions of the in-place fatigue response, which is a key input for any life extension requests, is dependent on the operating condition during the life of field including fluid contents and top tension. One solution to reduce this uncertainty is to deploy a fatigue monitoring system to assure the long-term integrity and performance of these riser systems. This paper presents results from a recent TTR monitoring campaign and focuses on the impact of top tension variation on riser motion and fatigue response in the field. Standalone and ROV deployable motion loggers offer a low cost and robust method of fatigue monitoring. The motion loggers are installed at discrete locations along the TTR to measure riser motions and then determine fatigue accumulations. During one of the recent monitoring campaigns, riser top tension was changed due to operational requirements, which in turn affected the riser fatigue response in the field. Field data is collected from two periods for two TTRs. The top tension was adjusted between each campaign allowing the effect of tension on riser fatigue response to be better understood using field measurements. The resulting riser motions and fatigue accumulations will be presented to demonstrate the sensitivity to top tension and highlight the importance of maintaining good records during the field life. Currently, there is no single guideline in the US that addresses TTR life-extension programs in detail. The results from this monitoring program are one step forward in better understanding system behavior of deep water TTRs and assessing the feasibility of an extended service life.

scholarly journals Four Dissemination Pathways for a Social Media–Based Breastfeeding Campaign: Evaluation of the Impact on Key Performance Indicators (Preprint)

2019 ◽  
Author(s):  
Kassandra Harding ◽  
Rafael Pérez-Escamilla ◽  
Grace Carroll ◽  
Richmond Aryeetey ◽  
Opeyemi Lasisi
Keyword(s):  
Social Media ◽  
Performance Indicators ◽  
Performance Indicator ◽  
Low Cost ◽  
Social Media Marketing ◽  
Campaign Evaluation ◽  
Indicator Data ◽  
And Performance ◽  
Top 40 ◽  
The Impact

BACKGROUND Social media utilization is on the rise globally, and the potential of social media for health behavior campaigns is widely recognized. However, as the landscape of social media evolves, so do techniques used to optimize campaign dissemination. OBJECTIVE The primary aim of this study was to evaluate the impact of 4 material dissemination paths for a breastfeeding social media marketing campaign in Ghana on exposure and engagement with campaign material. METHODS Campaign materials (n=60) were posted to a Facebook and Twitter campaign page over 12 weeks (ie, baseline). The top 40 performing materials were randomized to 1 of 4 redissemination arms (control simply posted on each platform, key influencers, random influencers, and paid advertisements). Key performance indicator data (ie, exposure and engagement) were extracted from both Facebook and Twitter 2 days after the material was posted. A difference-in-difference model was used to examine the impact of the dissemination paths on performance. RESULTS At baseline, campaign materials received an average (SD) exposure of 1178 (670) on Facebook and 1071 (905) on Twitter (n=60). On Facebook, materials posted with paid advertisements had significantly higher exposure and engagement compared with the control arm (<italic>P</italic>&lt;.001), and performance of materials shared by either type of influencer did not differ significantly from the control arm. No differences in Twitter performance were detected across arms. CONCLUSIONS Paid advertisements are an effective mechanism to increase exposure and engagement of campaign posts on Facebook, which was achieved at a low cost.

scholarly journals Benefit and performance impact analysis of using hydrogen fuel cell powered e-taxi system on A320 class airliner

2019 ◽  
Vol 123 (1261) ◽  
pp. 378-397
Author(s):  
J. A. Stockford ◽  
C. Lawson ◽  
Z. Liu
Keyword(s):  
Fuel Cell ◽  
Large Scale ◽  
Impact Analysis ◽  
Low Cost ◽  
Operating Cost ◽  
Maintenance Cost ◽  
Hydrogen Fuel Cell ◽  
Hydrogen Fuel ◽  
And Performance ◽  
The Impact

ABSTRACTThis paper presents the work carried out to evaluate the benefits and performance impacts of introducing a hydrogen fuel cell powered electric taxiing system to a conventional short-haul aircraft. Tasks carried out in this research and reported in this paper include the initial system design, hydrogen tank initial sizing, calculation of the impact on fuel burn and emissions and the evaluation of the effects on Direct Operating Cost (DOC). The Airbus A320 has been selected as the datum aircraft for sizing the system, and the benefits analysis is particularly focused on the fleet composition and financial data of a Europe-based, low-cost, large-scale A320 family operator in 2016. The maximum power capacity of 400 kW has been sized based on the rolling friction coefficient of 0.02. Based on the operator’s 2016 financial, up to 1% fuel reduction can be achieved using the proposed system and the reduction in total maintenance cost is expected to be up to 7.3%. Additionally, up to 5.97% net profit improvement is estimated in comparison with the annual after-tax profit of the datum operator in 2016.

scholarly journals Service fitness ladders: improving business performance in low cost and differentiated markets

2017 ◽  
Vol 37 (10) ◽  
pp. 1266-1303 ◽  
Author(s):  
Alex Hill ◽  
Richard Cuthbertson ◽  
Benjamin Laker ◽  
Steve Brown
Keyword(s):  
Business Performance ◽  
Low Cost ◽  
Differentiated Services ◽  
Business Strategies ◽  
Direct Result ◽  
Content Type ◽  
Strategic Fit ◽  
Market Needs ◽  
And Performance ◽  
The Impact

Purpose The purpose of this paper is to present 13 propositions about how internal strategic fit (often referred to as fit) impacts the business performance of low cost and differentiated services. It then uses these relationships to develop two “fitness ladder” frameworks to help practitioners understand how to improve fit given their business strategy (low cost or differentiation) and performance objectives (operational, financial or competitiveness). Design/methodology/approach In total, 11 strategic business units were studied that perform differently and provide a range of low cost and differentiated services to understand how changes in internal strategic fit impacted business performance over a 7 year period. Findings The findings suggest aligning systems with market needs does not improve performance. Instead, firms serving low cost markets should first focus managers’ attention on processes and centralise resources around key processes, before reducing process flexibility and automate as many steps as possible to develop a low cost capability that is difficult to imitate. By contrast, firms serving differentiated markets should first focus managers’ attention on customers and then locate resources near them, before increasing customer contact with their processes and making them more flexible so they can develop customer knowledge, relationships and services that are difficult to imitate. Research limitations/implications Some significant factors may not have been considered as the study only looked at the impact of 14 internal strategic fit variables on 7 performance variables. Also, the performance changes may not be a direct result of the strategic fit improvements identified and may not generalise to other service organisations, settings and environments. Practical implications The strategic fit-performance relationships identified and the “fitness ladder” frameworks developed can be used by organisations to make decisions about how best to improve fit given their different market needs, business strategies and performance objectives. Originality/value The findings offer more clarity than previous research about how internal fit impacts business performance for low cost and differentiated services.

scholarly journals Are Personal Electric Vehicles Sustainable? A Hybrid E-Bike Case Study

2019 ◽  
Vol 12 (1) ◽  
pp. 32 ◽  
Author(s):  
Mihai Machedon-Pisu ◽  
Paul Nicolae Borza
Keyword(s):  
Life Span ◽  
Electric Vehicles ◽  
Low Cost ◽  
Storage System ◽  
Life Time ◽  
Storage Solutions ◽  
Hybrid Electric ◽  
And Performance ◽  
Sustainability Challenges ◽  
The Impact

As the title suggests, the sustainability of personal electric vehicles is in question. In terms of life span, range, comfort, and safety, electric vehicles, such as e-cars and e-buses, are much better than personal electric vehicles, such as e-bikes. However, electric vehicles present greater costs and increased energy consumption. Also, the impact on environment, health, and fitness is more negative than that of personal electric vehicles. Since transportation vehicles can benefit from hybrid electric storage solutions, we address the following question: Is it possible to reach a compromise between sustainability and technology constraints by implementing a low-cost hybrid personal electric vehicle with improved life span and range that is also green? Our methodology consists of life cycle assessment and performance analyses tackling the facets of the sustainability challenges (economy, society, and environment) and limitations of the electric storage solutions (dependent on technology and application) presented herein. The hybrid electric storage system of the proposed hybrid e-bike is made of batteries, supercapacitors, and corresponding power electronics, allowing the optimal control of power flows between the system’s components and application’s actuators. Our hybrid e-bike costs less than a normal e-bike (half or less), does not depend on battery operation for short periods of time (a few seconds), has better autonomy than most personal electric vehicles (more than 60 km), has a greater life span (a few years more than a normal e-bike), has better energy efficiency (more than 90%), and is much cleaner due to the reduced number of batteries replaced per life time (one instead of two or three).

Frequent 4D monitoring with DAS 3D VSP in deep water to reveal injected water-sweep dynamics

2020 ◽  
Vol 39 (7) ◽  
pp. 471-479 ◽  
Author(s):  
Denis Kiyashchenko ◽  
Albena Mateeva ◽  
Yuting Duan ◽  
Duane Johnson ◽  
Jonathan Pugh ◽  
...  
Keyword(s):  
Deep Water ◽  
Low Cost ◽  
Water Injection ◽  
Time Lapse ◽  
Reservoir Model ◽  
Seismic Profiles ◽  
Vertical Seismic Profiles ◽  
Distributed Acoustic Sensing ◽  
The Impact

Time-lapse monitoring using 3D distributed acoustic sensing vertical seismic profiles (DAS VSPs) is rapidly maturing as a nonintrusive low-cost solution for target-oriented monitoring in deep water. In a Gulf of Mexico field, DAS fibers deployed in active wells enable detailed tracking of the water flood in two deep reservoirs. Multiple tests in adverse well conditions let us understand the impact of source size and other factors on the spatially dependent quality of time-lapse DAS data and prove that excellent image repeatability is achievable under typical field conditions. Frequent repeat surveys allowed us to predict the timing of water arrival in a producer and to observe new water injection patterns that are important for understanding water-flood performance. Going forward, DAS 4D monitoring is envisioned as a tool that can assist with proactive wells and reservoir management, new well planning, and reservoir model updates.

Design and Performance of the Double Dislocation Perforated Shielding Plate Used in Vacuum Arc Deposition for High Quality Coating Deposition

2011 ◽  
Vol 340 ◽  
pp. 130-135
Author(s):  
Wen Chang Lang
Keyword(s):  
Low Cost ◽  
Film Structure ◽  
Vacuum Arc ◽  
High Quality ◽  
Ion Density ◽  
Movement Characteristics ◽  
Straight Line ◽  
Pass Through ◽  
And Performance ◽  
The Impact

Based on the different movement characteristics of macro-particles, ions and electrons in the plasma transmission, this paper developed a simple, easy device with low cost-- double dislocation perforated shielding plate used in the coupling enhanced magnetic field, which can also satisfy the requirements of preparing high-quality films; This paper also studied the impact of double dislocation perforated shielding plate on the transmission of arc plasma and film properties. The results showed that: compared with the physical fielding plate, in the realization of the resistance to macro-particles transferred in straight line, part of the ions can also pass through the perforated position in the double dislocation perforated shielding plate to increase the ion density behind the fielding plate, thus increasing the film’s deposition rate to some extent. At the same time, the double dislocation perforated shielding plate can significantly reduce the roughness of the film and improve the film's finish, while the film structure does not change.

scholarly journals Best practices for analyzing imputed genotypes from low-pass sequencing in dogs

2021 ◽  
Author(s):  
Reuben M. Buckley ◽  
Alex C. Harris ◽  
Guo-Dong Wang ◽  
D. Thad Whitaker ◽  
Ya-Ping Zhang ◽  
...  
Keyword(s):  
Best Practice ◽  
Association Studies ◽  
Low Cost ◽  
Effect Sizes ◽  
Genome Wide Association Studies ◽  
High Coverage ◽  
Best Practice Guidelines ◽  
Low Pass ◽  
And Performance ◽  
The Impact

AbstractAlthough DNA array-based approaches for genome-wide association studies (GWAS) permit the collection of thousands of low-cost genotypes, it is often at the expense of resolution and completeness, as SNP chip technologies are ultimately limited by SNPs chosen during array development. An alternative low-cost approach is low-pass whole genome sequencing (WGS) followed by imputation. Rather than relying on high levels of genotype confidence at a set of select loci, low-pass WGS and imputation rely on the combined information from millions of randomly sampled low-confidence genotypes. To investigate low-pass WGS and imputation in the dog, we assessed accuracy and performance by downsampling 97 high-coverage (> 15×) WGS datasets from 51 different breeds to approximately 1× coverage, simulating low-pass WGS. Using a reference panel of 676 dogs from 91 breeds, genotypes were imputed from the downsampled data and compared to a truth set of genotypes generated from high-coverage WGS. Using our truth set, we optimized a variant quality filtering strategy that retained approximately 80% of 14 M imputed sites and lowered the imputation error rate from 3.0% to 1.5%. Seven million sites remained with a MAF > 5% and an average imputation quality score of 0.95. Finally, we simulated the impact of imputation errors on outcomes for case–control GWAS, where small effect sizes were most impacted and medium-to-large effect sizes were minorly impacted. These analyses provide best practice guidelines for study design and data post-processing of low-pass WGS-imputed genotypes in dogs.

scholarly journals Four Dissemination Pathways for a Social Media–Based Breastfeeding Campaign: Evaluation of the Impact on Key Performance Indicators

JMIR Nursing ◽  
10.2196/14589 ◽  
2019 ◽  
Vol 2 (1) ◽  
pp. e14589
Author(s):  
Kassandra Harding ◽  
Rafael Pérez-Escamilla ◽  
Grace Carroll ◽  
Richmond Aryeetey ◽  
Opeyemi Lasisi
Keyword(s):  
Social Media ◽  
Performance Indicators ◽  
Performance Indicator ◽  
Low Cost ◽  
Social Media Marketing ◽  
Campaign Evaluation ◽  
Indicator Data ◽  
And Performance ◽  
Top 40 ◽  
The Impact

Background Social media utilization is on the rise globally, and the potential of social media for health behavior campaigns is widely recognized. However, as the landscape of social media evolves, so do techniques used to optimize campaign dissemination. Objective The primary aim of this study was to evaluate the impact of 4 material dissemination paths for a breastfeeding social media marketing campaign in Ghana on exposure and engagement with campaign material. Methods Campaign materials (n=60) were posted to a Facebook and Twitter campaign page over 12 weeks (ie, baseline). The top 40 performing materials were randomized to 1 of 4 redissemination arms (control simply posted on each platform, key influencers, random influencers, and paid advertisements). Key performance indicator data (ie, exposure and engagement) were extracted from both Facebook and Twitter 2 days after the material was posted. A difference-in-difference model was used to examine the impact of the dissemination paths on performance. Results At baseline, campaign materials received an average (SD) exposure of 1178 (670) on Facebook and 1071 (905) on Twitter (n=60). On Facebook, materials posted with paid advertisements had significantly higher exposure and engagement compared with the control arm (P<.001), and performance of materials shared by either type of influencer did not differ significantly from the control arm. No differences in Twitter performance were detected across arms. Conclusions Paid advertisements are an effective mechanism to increase exposure and engagement of campaign posts on Facebook, which was achieved at a low cost.

scholarly journals Best practices for analyzing imputed genotypes from low-pass sequencing in dogs

2021 ◽  
Author(s):  
Reuben M. Buckley ◽  
Alex C. Harris ◽  
Guo-Dong Wang ◽  
D. Thad Whitaker ◽  
Ya-Ping Zhang ◽  
...  
Keyword(s):  
Best Practice ◽  
Association Studies ◽  
Low Cost ◽  
Effect Sizes ◽  
Genome Wide Association Studies ◽  
High Coverage ◽  
Best Practice Guidelines ◽  
Low Pass ◽  
And Performance ◽  
The Impact

AbstractAlthough DNA array-based approaches for genome wide association studies (GWAS) permit the collection of thousands of low-cost genotypes, it is often at the expense of resolution and completeness, as SNP chip technologies are ultimately limited by SNPs chosen during array development. An alternative low-cost approach is low-pass whole genome sequencing (WGS) followed by imputation. Rather than relying on high levels of genotype confidence at a set of select loci, low-pass WGS and imputation relies on the combined information from millions of randomly sampled low confidence genotypes. To investigate low-pass WGS and imputation in the dog, we assessed accuracy and performance by downsampling 97 high-coverage (>15x) WGS datasets from 51 different breeds to approximately 1x coverage, simulating low-pass WGS. Using a reference panel of 676 dogs from 91 breeds, genotypes were imputed from the downsampled data and compared to a truth set of genotypes generated from high coverage WGS. Using our truth set, we optimized a variant quality filtering strategy that retained approximately 80% of 14M imputed sites and lowered the imputation error rate from 3.0% to 1.5%. Seven million sites remained with a MAF > 5% and an average imputation quality score of 0.95. Finally, we simulated the impact of imputation errors on outcomes for case-control GWAS, where small effect sizes were most impacted and medium to large effect sizes were minorly impacted. These analyses provide best practice guidelines for study design and data post-processing of low-pass WGS imputed genotypes in dogs.

Terrestrial Heat Repository for Months of Storage (THERMS): A Novel Radial Thermocline System

2021 ◽  
Author(s):  
Clifford K. Ho ◽  
Walter Gerstle
Keyword(s):  
Heat Transfer ◽  
Low Cost ◽  
Storage System ◽  
Electrical Heating ◽  
Heat Transfer Fluid ◽  
Present System ◽  
System Sensitivity ◽  
Thermal Plant ◽  
And Performance ◽  
The Impact

Abstract This paper describes a terrestrial thermocline storage system comprised of inexpensive rock, gravel, and/or sand-like materials to store high-temperature heat for days to months. The present system seeks to overcome past challenges of thermocline storage (cost and performance) by utilizing a confined radial-based thermocline storage system that can better control the flow and temperature distribution in a bed of porous materials with one or more layers or zones of different particle sizes, materials, and injection/extraction wells. Air is used as the heat-transfer fluid, and the storage bed can be heated or “trickle charged” by flowing hot air through multiple wells during periods of low electricity demand using electrical heating or heat from a solar thermal plant. This terrestrial-based storage system can provide low-cost, large-capacity energy storage for both high- (∼400–800°C) and low- (∼100–400°C) temperature applications. Bench-scale experiments were conducted, and computational fluid dynamics (CFD) simulations were performed to verify models and improve understanding of relevant features and processes that impact the performance of the radial thermocline storage system. Sensitivity studies were performed using the CFD model to investigate the impact of the air flow rate, porosity, particle thermal conductivity, and air-to-particle heat-transfer coefficient on temperature profiles. A preliminary technoeconomic analysis was also performed to estimate the levelized cost of storage for different storage durations and discharging scenarios.

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