bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimization of the Trench Dimensions for Bahrain LNG Import Terminal Project
Authors: Seo Donghee , Kim Youngho , Hossain Muhammad Shazzad 
Published: December 2020

Abstract
Large deformation finite element analyses were carried out to investigate the optimized trench geometry for 24 inch (610 mm) diameter subsea pipelines and power cables (33 kV; outer diameter = 186 mm) used for transporting gas in shallow water depth (approximately 15 m), with an emphasis being on pipe-soil interaction assessment. An extensive parametric investigation was performed varying the relative density of the backfill sand (35%, 54% and 78%) and buried depth (1.89 and 3.14 diameters). Upward and lateral soil failure mec hanisms around a pipe uplifting in a backfill sand layer were compared. The failure mechanisms were manifested by shear band formation and subsequent propagation. It was shown that the trench dimensions originally designed based on conventional conservative approaches can be reduced by up to 10.6% in loose backfill sand (ID = 35%) and 8.7% in dense backfill sand (ID = 78%), leading to minimize cost and time of trenching and backfilling.
Coupled CFD and FEA to Predict the Dynamic Structural Response of Modern Cruise Ship Deck Outfitting due to Wind-Induced Vibrations
Authors: Kivelä Eetu , Lakshmynarayanana P. A. , Hirdaris Spyros 
Published: December 2020

Abstract
Recent market trends in the cruise industry aim to provide land-based attractions on mega-cruise liners deck amusements. The structures used are mega-lightweight structures that comprise of slender beams to reduce added weight. They may be subject to dynamic wind-induced resonance as a result of fluctuating forces due to vortex shedding occurring close to the natural frequency of the structure. This paper investigates the structural responses due to wind-induced vibrations in the context of a ship deck outfitting by coupling CFD and FEA. The simulations are performed using one- and two-way coupling FSI to gain insights into the differences between the predicted responses. A deck amusement structure is idealized as an aluminum portal frame subjected to a constant head wind. Transient one- and two-way coupled simulations, based on Reynolds-Averaged Naiver-Stokes (RANS) and linear elastic 3D FEA are conducted. The predictions are compared against quasi-dynamic beam element idealizations.
Vibratory Installation Study of a Monopile in Dense Sand
Authors: Holeyman Alain , Whenham Valérie , Peralta Proserpine , Ballard Jean-Christophe , Chenicheri Pulukul Sunil 
Published: December 2020

Abstract
The assessment of monopile installation by means vibratory driving is discussed for a platform located in the Dutch Sector of the North Sea. The vibratory driving analysis of the 4.7 m diameter monopile was performed using the “Hypervib” method in order to evaluate the performance of a 960 kg.m excentric moment vibrohammer. The results of the installation study indicated that the monopile could be installed up to a penetration depth of 31.5 m considering the full nominal power and frequency (23 Hz) of the specified vibrohammer.
The frequency of the vibrator is shown to influence the projected penetration of the monopile. In particular, the “Hypervib” method indicated that refusal could be encountered if the effective frequency of the vibrator dropped below 20 Hz. As a consequence, monitoring measures were recommended to mitigate/characterize the risks of early refusal.
Reduction in Mooring System Lifetime due to Corrosion and Severe Storms
Authors: MacNicoll Michael , Akers Richard , Sharman Krish Thiagarajan , Hsu Wei-Ting 
Published: December 2020

Abstract
We report on a multi-year investigation into mechanisms of fatigue, corrosion, and abrasion on floating offshore wind turbine (FOWT) mooring systems funded by the U.S. Bureau of Safety and Environmental Enforcement (BSEE). The project team examined the efficacy of standards-based design procedures as they relate to fatigue damage and material degradation.
Best practice design encourages applying 50% of a mooring chain corrosion allowance to fatigue calculation. However, the project team concludes that this practice may underestimate fatigue damage when the corrosion rate is high relative to the component diameter. A more robust accounting of corrosion rate in fatigue calculations decreased the predicted lifetime of a mooring system by over 80% in one small scale field deployed case study. This discrepancy was reduced in a similar comparison of a full-scale system.
Best practice design focuses on operational and normal sea states for fatigue damage calculation. The project team has concluded, through simulation of validated case studies, that severe storms may contribute significant fatigue damage to chain moorings. Over 50% of the fatigue on a prototype FOWT mooring was caused by storms which occur less than 0.2% of the time. A single 20-year storm produced over 15% of the anchor fatigue of a theoretical full-scale FOWT.
By augmenting standards-based predictions of the degradation rate of chain-based mooring systems through better accounting for corrosion and abrasion rates over the full lifetime of the mooring system and including rare, extreme storms in fatigue calculations, the engineer or developer can plan ahead and reduce the risk of dangerous and expensive failures.
Numerical Studies on Dynamic Behavior of Tubular Pipes Under Repeated Impacts
Authors: Zhu Ling , Wang Xiangui , Guo Kailing , Ma Bin 
Published: December 2020

Abstract
The tubular pipes of Jacket platform may be frequently subjected to repeated impact loadings from vessels and dropped objects during the operation life, which may lead to serious damages to the platform. In this paper, the numerical studies on dynamic behavior of tubular pipe subjected to repeated impact loadings was performed. The deformation profile and permanent deflection in numerical simulation were compared with those in experiment, and good agreement was achieved. Besides, the mechanism of deformation accumulation and energy absorption were analyzed. Results showed that, the tubular pipe mainly produced transverse expanding and local dent, the global bending was very small. The permanent deflection at the middle of the pipe increased as the impact numbers increased, while the increment decreased. In addition, with the increase of impact number, the elastic deformation energy stored by the tubular pipe increased, and the plastic deformation energy decreased.
Additive Manufacturing in the Oil and Gas Industry Overview
Authors: De Bernardi Carlo 
Published: December 2020

Abstract
The API 20S Standard is designed to play a crucial role in leveraging Additive Manufacturing (AM) to foster innovation in the oil and gas industry. The paper, in association with the standard, will facilitate the understanding of how AM will enable equipment design improvements, faster prototyping, and better inventory management. By way of discussing the progress, challenges, and lessons learned from the standardization process, the paper aims to encourage a safer, broader, and faster adoption of AM technologies in the mainstream oil and gas applications.
The paper will summarize the streamlining process, feedback from the API 20S task group, and current status of the standardization efforts. Additionally, upcoming challenges and the potential for the oil and gas industry industries to contribute to the standard will be summarized. The paper will also showcase a novel tiered approach (Additive Manufacturing Specification Levels) to allow the users of the document to match different levels of criticality.
Drilling Cutting Analysis to Assist Drilling Performance Evaluation in Hard Rock Hole Widening Operation
Authors: Ahmed Daiyan , Xiao Yingjian , de Moura Jeronimo , Butt Stephen D. 
Published: December 2020

Abstract
Optimum production from vein-type deposits requires the Narrow Vein Mining (NVM) process where excavation is accomplished by drilling larger diameter holes. To drill into the veins to successfully extract the ore deposits, a conventional rotary drilling rig is mounted on the ground. These operations are generally conducted by drilling a pilot hole in a narrow vein followed by a hole widening operation. Initially, a pilot hole is drilled for exploration purposes, to guide the larger diameter hole and to control the trajectory, and the next step in the excavation is progressed by hole widening operation. Drilling cutting properties, such as particle size distribution, volume, and shape may expose a significant drilling problem or may provide justification for performance enhancement decisions. In this study, a laboratory hole widening drilling process performance was evaluated by drilling cutting analysis. Drill-off Tests (DOT) were conducted in the Drilling Technology Laboratory (DTL) by dint of a Small Drilling Simulator (SDS) to generate the drilling parameters and to collect the cuttings. Different drilling operations were assessed based on Rate of Penetration (ROP), Weight on Bit (WOB), Rotation per Minute (RPM), Mechanical Specific Energy (MSE) and Drilling Efficiency (DE). A conducive schedule for achieving the objectives was developed, in addition to cuttings for further interpretation. A comprehensive study for the hole widening operation was conducted by involving intensive drilling cutting analysis, drilling parameters, and drilling performance leading to recommendations for full-scale drilling operations.
Tubular Connection Assembly for Improved Fatigue Performance of Metallic Risers
Authors: Mansour Ghiath (Guy) 
Published: December 2020

Abstract
Fatigue is a primary challenge in the design of steel catenary risers (SCRs) and different measures and methods are utilized to mitigate it. Traditional upset ends and steel lazy wave risers (SLWRs) are such methods to mitigate fatigue.
SLWRs were first used in 2009 on the Espirito Santo floating, production, storage, and offloading (FPSO) vessel of Shell Company’s Parque das Conchas (BC-10) project offshore Brazil. SLWRs have been used increasingly since then and gained popularity especially in recent years.
A novel patented tubular connection assembly is presented herein which improves the fatigue life of SCRs and welded connections in general.
This novel tubular connection assembly has many advantages. It overcomes the thickness limitation of welding traditional upset ends and reduces offshore welding time, cost, and risk.
When used in simple SCRs, this novel tubular connection assembly renders simple SCRs an alternative robustly viable at significantly lower cost, shorter schedule, and many additional advantages as compared to SLWRs. Of such many advantages, simple SCRs are simpler to configure, analyze, design, and install using wider installation methods and vessels. They also use less material and offer better short- and long-term integrity especially for insulated SCRs. In addition, they have smaller footprint and are less prone to clashing.
Quantitative Characterization, Design Considerations and Sustainable Resource Management for Middle Eastern Tight Gas Reservoirs
Authors: Suboyin Abhijith , Motiur Rahman Md , Haroun Mohamed 
Published: December 2020

Abstract
Augmented by recent activities in the oil and gas industry, it can be seen that an economical and efficient hydraulic fracturing job has become critical for the successful development of unconventional reservoirs. However, exploitation of unconventional reservoirs is heavily water-intensive as compared to conventional reservoirs. Given this concern, it is essential to reform how water is managed within the industry, especially in water scarce regions such as the Middle East.
In this study, a comprehensive investigation that deals with the quantification of changes with respect to variation in prime contributors within a traditional fracture design process is presented. This can assist to determine the distinct contributions of an element within fracture design parameters, as they are imperative to evaluate the nature of fracture propagation. After an extensive assessment, a set of natural fractures were introduced to the system and the system behavior was further investigated to identify their behavior and optimize resource management. Based on an iterative process, the results of the constructed simulation models were analyzed in depth and validated with field data.
Overall, the results indicate that for the given field conditions, fluid and proppant optimization are critical to achieve maximum recovery. The dominance of parameters such as fracture width, fracture length, proppant placement and Young’s Modulus are also illustrated in depth. To examine the associated response on long-term productivity, the results have been extended to current field practices and cases. A rough analysis was conducted in-house, on geological data from a candidate field in the Middle East. Findings shows the potential to optimize and reduce the required water for an operation by 1.3 million gallons. This further highlights the need to optimize and tailor an adaptable workflow, which is proposed in this study, for water scarce regions such as the Middle East.
In addition to ultimately assisting in verification of modern best practices, this investigative approach will create a paradigm for future studies within the Middle Eastern region to assist in a simplistic prediction of fracture propagation behavior and its associated response to optimize water usage. The results have also been extended along with comparisons to current field practices.
Study on Formation and Dissociation of Methane Hydrate in Sandstone Using Low-Field Nuclear Magnetic Resonance Technology
Authors: Ji Yunkai , Hou Jian , Liu Yongge , Du Qingjun 
Published: December 2020

Abstract
Natural gas hydrate, as an unconventional resource, has been attracting increasing attention. Understanding the characteristics of methane hydrate formation and dissociation in porous media is important for developing gas hydrate-bearing reservoirs. This work discusses the use of low-field nuclear magnetic resonance (LF-NMR) technology to investigate the formation and dissociation of methane hydrate in the sandstone.
In this work, an experimental assembly wherein methane hydrate can form and dissociate, is used to conduct LF-NMR measurements. LF-NMR, as a noninvasive measurement technology, combines the transverse relaxation time (T2) measurement with the magnetic resonance imaging (MRI). T2 measurements can explore the characteristics of methane hydrate formation and dissociation in core samples from a pore-scale perspective. MRI can display the spatial distribution of water from a core-scale perspective. The excess-gas method and the excess-water method are successively applied to form methane hydrate, and depressurization is applied to dissociate methane hydrate in the laboratory. The characteristics of methane hydrate formation and dissociation is studied in the sandstone.
Experimental results show that the signal intensity of short T2 and long T2 decreases simultaneously in the process of the methane hydrate formation using the excess-gas method, indicating that methane hydrate is formed in both small and large pores. When using the excess-water method, the signal intensity of long T2 decreases, and the signal intensity of short T2 increases in the process of the methane hydrate formation, indicating that methane hydrate is mainly formed in large pores. Methane hydrate is dissociated simultaneously in both small and large pores when using the depressurization method. Water content in small pores gradually increases. Capillary pressure causes some water to remain in the core samples following dissociation. Water content in large pores decreases initially and then increases during depressurization. In the early stages of depressurization, more water leaves large pores than is generated by hydrate dissociation. In the later stages of depressurization, less water leaves the large pores than is generated by hydrate dissociation.
This study may inspire the new understanding on distribution of fluid in sediments during the process of accumulation and exploitation of natural gas hydrates.
Influence of Soil’s Vertical Stiffness on Estimation of Fatigue Life for Steel Catenary Risers (SCRs)
Authors: Cao Jianchun , Chen Xingnian , Cheng Jingyun , Cao Peimin 
Published: December 2020

Abstract
Fatigue damage estimation is a key part in a Steel Catenary Riser (SCR) system design. The riser-soil interaction has a significant influence on the fatigue assessment for a SCR system at the Touch-Down Zone (TDZ) because the soil’s vertical stiffness is a critical parameter. The conventional methods developed to calculate the soil’s vertical stiffness, for example, DNV method [10], Bridge method [4] and Audibert method [3], were based on the assumption that at the TDZ area the soil mass being interacted by the pipe is always under intact condition. Recently, Chen et al. published a newly developed method [5, 6], which was based on the laboratory test results carried out by Texas A&M University in the late 1980s and was further verified by recent laboratory displacement-controlled tests by Texas A&M University [2], resulting in softer soil’s vertical stiffness. In order to understand the difference between Chen method and the conventional methods as well as the influence of Chen method on the SCR design, a study was carried out for a given soil condition and three typical sizes of riser pipes and is documented in this paper. In this paper, firstly, various methods used to calculate soil’s vertical stiffness, i.e., DNV method, Bridge method, Audibert method, and Chen method, were briefly introduced. Secondly, a discussion was performed on the model of the conventional methods and the model of Chen method. Thirdly, as an example for a given soil condition, the soil’s vertical stiffness was estimated using these methods respectively for 6″-dia., 12″-dia., and 18″-dia. riser pipes. Finally, the fatigue damages for various riser pipes were computed using the estimated soil’s vertical stiffness and a comparison on the estimated fatigue damages was performed. The study results showed that the soil’s vertical stiffness estimated by Chen method was about one order magnitude weaker than these estimated by the conventional methods. In other words, the soil’s vertical stiffness estimated by the conventional methods was about 5 to 11 times that estimated by Chen method. The pipe’s fatigue life estimated using the soil’s vertical stiffness of Chen method was about 1.5 times (i.e., 50% longer than) that estimated using the soil’s vertical stiffness of the conventional methods. These study results could improve a SCRs designer’s understanding on: 1) the difference between the model of the conventional methods and the model of Chen method, 2) the impact of Chen method on the estimated fatigue life, and 3) that as the model of the conventional methods is a closer representative of the prototype and their results are more conservative, it is recommended to use the conventional methods for SCRs design. Eventually, these will help the designers to select an appropriate method for calculating the soil’s vertical stiffness in the SCRs design.
Implementation of the ATLAS-SUSY-2019-08 analysis in the MadAnalysis 5 framework (electroweakinos with a Higgs decay into a bb̄ pair, one lepton and missing transverse energy; 139 fb−1)
Authors: Goodsell Mark D. 
Published: December 2020

This is the validation note for the recast in MadAnalysis 5 of the study ATLAS-SUSY-2019-08: a search for direct production of electroweakinos in final states with one lepton, missing transverse momentum and a Higgs boson decaying into two [Formula: see text]-jets in [Formula: see text] collisions at [Formula: see text] = 13 TeV with the ATLAS detector, using an integrated luminosity of 139 fb[Formula: see text]. The recasting code is validated against cutflows and expected signal events for benchmark scenarios, and the exclusion limits are reproduced for a simplified supersymmetric electroweakino sector consisting of a degenerate wino decaying to a light stable bino.
Turismo de Base Comunitária: outras economias na mira da emancipação social
Authors: Leão Carolina Valéria de Moura 
Published: December 2020

O sentido de comunidade tem sido a ideia-chave do Turismo de Base Comunitária (TBC), associando formas comuns de organização e gestão, em que esta é a principal beneficiária. Este artigo procura conhecer que mecanismos colaborativos e de gestão as comunidades recetoras têm desenvolvido, que sinalizem outras lógicas assentes na autogestão e na solidariedade, contrariamente à tendência da concentração empresarial e do lucro. Por sua vez, se estes se refletem em uma proposta de transformação social, com o aparecimento de novos sujeitos protagonistas no processo. Os elementos empíricos são obtidos a partir do recorte das informações incluídas no relatório de avaliação final externa de um projeto de TBC, em Timor Leste, tendo como foco três comunidades/cooperativas. O estudo revela a existência de novos sujeitos que se organizam na partilha de poderes e saberes, a partir de códigos de conduta e um conjunto de procedimentos de gestão colaborativa, apontando para um horizonte de emancipação social.
Transdiaphragmatic Chest Wall Herniation
Authors: Meader Anna G. , Ciraulo David L. , Rappold Joseph F. , Sawhney Jaswin S. 
Published: December 2020

Background The combination of traumatic simultaneous diaphragmatic rupture and chest wall herniation remains rare, with 42 cases of traumatic transdiaphragmatic intercostal hernia (TDIH) reported in the literature since 1946. An accurate count of cases is difficult to obtain, as TDIH nomenclature has been variable. 1 - 5 Risk factors for traumatic TDIH are not well established. As these injuries are uncommon, best management techniques have yet to be established. Reported repair techniques include primary closure, closure with mesh, and implantation of prosthetic or autologous material. We present our single-center series of 7 patients, the largest reported to our knowledge, and discuss the challenges of repairing these difficult injuries. Methods After obtaining institutional review board approval, data were abstracted from the electronic medical record on all adults who underwent evaluation and treatment for traumatic TDIH between July 2014 and January 2019. Results Of the 7 cases of traumatic TDIH, 6 patients developed TDIH secondary to cough; the seventh patient presented with chronic chest wall pain after an episode of heavy lifting. All patients were obese or overweight. Pain and a “popping sensation” were the most common presenting symptoms. All patients underwent operative intervention with primary repair of the diaphragm and suture approximation of the ribs. 3 patients had onlay mesh repair of the chest wall and/or abdominal wall. 1 patient had plating of his rib fracture. 3 patients had a recurrence of the intercostal portion of the hernia No patients have undergone reoperation thus far. Discussion While previously thought to more commonly occur on the left side due to the protective effects of the diaphragm, 2 the majority in this series had right-sided injuries. Herniation through the ninth-10th interspace remains the most common location. 4 Computed tomography imaging should be used for diagnosis and operative planning. It is best to manage these hernias acutely to re-establish normal anatomy. Mesh may be required in delayed reconstructions of if the chest wall cannot be re-approximated. Rib plating should be considered in cases of instability or flail. High rates of complications are not unexpected given the complicated and rare nature of the injury. Given the high rate of intercostal hernia recurrence, it is likely that mesh repair or should be more often used in the treatment of this injury.