bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regulatory Design Assessment of Cold Bonded Fasteners
Authors: Quéméré Marie-Odette , Court Jean-Philippe , Montaufray Pierre , Errotabehere Xabier , Noury Philippe , Zakariyya Ksenia , Martinsen Olin Henning 
Published: October 2019

Abstract
An increasing number of Brazilian floating platform units are currently entering a mature age, inducing numerous asset integrity issues. As corrosion damages FPSOs’ hull structures and outfitting, repairs and/or modifications have to be performed in explosive environment. Those features create important operational challenges, both in terms of safety and production continuity, when hot work techniques are to be used. This is the reason why Cold Pad has developed a cold work technique based on a heavy duty, bonded, mechanical fastener called C-CLAW™. On FPSOs, this novel solution allows today to repair primarily corroded outfitting like handrails, pipe supports, cable trays, electrical boxes and the like. Cold Pad and DNV GL are working together on a design philosophy, a regulatory approach, and a validation programme based on the DNVGL-ST-C501 and the so-called load and resistance factor design (LRFD) format. The article focuses on the application of the regulatory approach for the demonstration of the capacity and reliability of these fasteners. The strength of the bondline and steel fastener components, with their multiple failure mechanisms, are addressed and mainly supported by short-term test results.
The article details the main challenges of that new design approach throughout the service life of bonded fasteners, and includes results and findings related to e.g. strength, susceptibility to temperature, and allowable short-term mechanical capacities based on regulatory safety factors. It also provides the early conclusions in terms of application on FPSOs and recommendations regarding fire hazards. The novelty of these bonded mechanical fastener lies, firstly in the industrial product itself, and secondly in the application of one of the most recognized offshore standards for composite components to derive its regulatory mechanical rated capacity.
An Analytical Method to Combine Environmental Attributes to Generate the Matrix of Importance of Environmental Impacts for the Decommissioning of Subsea Installations in Brazil
Authors: De Oliveira Luiz Fernando Seixas , Schaffel Silvia Blajberg , Do Amaral Netto Joaquim Domingues 
Published: October 2019

Abstract
A new method developed to evaluate the performance measure of some sub-criteria of the environmental criterion in a Comparative Assessment of various options of the decommissioning of subsea installations in Brazil is presented. The method is based on an adaptation of that proposed by IBAMA in Technical Note N°. 10/2012 (TN 10) used for assessment of environmental impacts required for the licensing of offshore activities in Brazil. By requirement of the Comparative Assessment methodology, there is a need for a numerical evaluation that allows comparing the performance of one alternative over the others. An analytical method was developed based on the combination of environmental attributes that contribute for the magnitude of the impacts (frequency, intensity, extension and duration) and sensitivity of the environmental factors affected (relevance, resilience and reversibility). The importance of the impacts is given by the combination of the environmental sensitivity with the magnitude of the impacts, in the called "Environmental Impact Importance Score Matrix". The proposed method provides a performance measure that allows comparing and prioritizing each decommissioning option according to the proposed criteria. It reduces the subjectivity in assessing the importance of the environmental impacts and provides greater transparency and traceability in the assessment of the impacts. As an example, the proposed method is applied for the decommissioning of a rigid pipeline between two platforms in Campos Basin, where the considered decommissioning options are: (a) complete removal by cut and lift and (b) leave in situ. For this particular case, the assessment of the proposed environmental sub-criteria revealed that Option (b) was the preferred option with respect to the impacts on marine and onshore environment.
Technology Intelligence Analysis Based on Document Embedding Techniques for Oil and Gas Domain
Authors: Cordeiro Fábio Corrêa , Gomes Diogo da Silva Magalhães , Gomes Flávio Antônio Machado , Texeira Renata Cristina 
Published: October 2019

Abstract

Objectives/Scope
we propose a methodology based on document embedding techniques for applying Technology Intelligence Analysis in Oil and Gas (O&G) domain. We build a specialized corpus in O&G domain and train a Vector Space Model (VSM) to represent each document as a vector, in such a way that the distance between two vectors captures their semantic similarity. We explore different analysis on this VSM to infer relations between documents, in order to obtain new insights in a strategic context.

Methods Procedures
this proposed methodology is based on Natural Language Processing (NLP) techniques to obtain strategic insights in a technology intelligence analysis scenario. It consists on generating a vector space model (VSM) induced from a domain-specific Oil and Gas corpus, composed of thousands of scientific articles collected from the Elsevier online database. We explore an approach to represent different entities - such as articles, authors and keywords - in the same vector space, making it possible to correlate them and infer relations of similarity based on their cosine distance. An evaluation metric is also provided in order to assist the training process and hyperparameters optimization.

Results, Observations, Conclusions
Oil and Gas highly technical vocabulary represents a challenge to NLP applications, in which some terms may assume a completely different meaning from the general - context domain. In this scenario, gathering an Oil and Gas corpus and training specialized vector space models for this specific domain allows increasing the quality in Technology Intelligence Analysis. The most significant finding is that we were able to explicit the semantic relationships between different entities of interest in the same VSM, also linking these relationships together with some additional metadata. An interesting application is to compare the publications of authors affiliated to two or more O&G companies at a given time. These non-trivial correlations are important to gain strategic insights considering a Technology Intelligence Analysis scenario.

Novel/Additive Information
the novelty of this proposed methodology is the possibility of exploring new insights when correlating different entities in a technology intelligence scenario for the Oil and Gas domain, using a simple yet efficient approach based on document embedding techniques. This method applies some advanced NLP techniques to quickly process more than a hundred thousand documents in a few seconds, without requiring complex hardware resources, which would be impractical using traditional techniques.
Life Extension of Offshore Structure Using Machine Learning
Authors: Bhowmik Subrata 
Published: October 2019

Abstract
The objective of the paper is to demonstrate the Machine Learning (ML) based Structural Integrity Management (SIM) Methodology and its application for the life extension of the offshore structure. This paper also illustrates how the sensor data are used to generate an ML based predictive model and how it will be used to minimise the inspection cost without using the traditional Risk Based Inspection(RBI) methodology. Structural assessment, real-time monitoring and predictive maintenance are the three main aspects of the life extension process for the offshore structure. Usually, the structures are designed for a fixed design life, but during life extension process it is assessed through FE analysis and various inspection methods whether the structure will have adequate fatigue life for another 5-10 year. But running fatigue analysis is computationally expensive as well as inspection also increase the operational cost. Sensors are installed on the offshore structure, and the stress, acceleration, wave, current etc. are measured and transmitted through wired or wireless sensor network and stored in cloud computing. This data is used for predicting the new wave and current data for 1 and 10-year return period. The acceleration data is used to get the modal frequencies and calibrate the FE model. Also, the measured stress value is compared with the FE model generated stress value, and the FE model is further calibrated.
Machine Learning Algorithm (Recurrent Neural Network) is used to generate the predictive maintenance schedule based on the data-driven fatigue prediction model created from the measurement data. The case study shows the life extension of the offshore jacket structure with proposed machine learning based life extension methodology.
The data-driven fatigue predictive model generates the remaining fatigue life, and it is compared with the fatigue life calculated from the FE model. It shows a good match and within 5-10% inaccuracy limit. The predictive maintenance schedule is developed based on the remaining fatigue life. ML-based model significantly reduces the computational cost as well as the real-time data also improves the fatigue life calculation accuracy. Hence, though predictive maintenance, the overall operational cost will be reduced significantly.
Salt Creeping Analysis on Deepwater Wells Submitted to Cooling Operations on Trapped Annular
Authors: Agostini Cristiano Eduardo , Almeida Luiz Felippe Medeiros , Júnior Nelson Moreira , Magalhães Mateus Dias , Roman Roger Savoldi , Schnitzler Eduardo , Silva Alan Pinheiro 
Published: October 2019

Abstract
This paper presents the finite element analysis of salt-creep behavior on deepwater wells with trapped annulus, considering cooling effects caused by injection operations. In addition, this effect was considered coupled with salt-creep behavior and its influence on casing collapse design under transient and steady state well operation. The scenarios of injection flow rate and temperature profile were analyzed using the coupled approach, for salt creeping and thermal trapped annulus. The wellbore profile is a typical Pre Salt Brazilian Offshore, where rock salt layer is confined under two casing shoes. The injection wells operation results in a pressure decrease in a confined annulus due to thermal cooling between casing and salt formation. Due to this pressure drop on the trapped annulus, the salt creeping behavior tends to increase, and proper casing stress verification must be done. The finite elements analysis for salt creeping was modeled using commercial finite elements software package, and thermal profile for transient and steady state injection was obtained using thermal casing design software. The coupled effects were evaluated using commercial casing design software. Preliminary studies have shown that there is a great influence on the salt creeping response on confined annulus when subjected to a pressure decrease due to thermal cooling on trapped annulus, caused by water injection operation. It is observed that there is a growth of the confined annular pressure due to salt creeping effects and that there is an acceleration in this phenomenon. The analysis also shows that casing collapse safety margin is time dependent considering a given operation. After well shutdown, the natural heating of the confined annulus occurs due to geothermal effects, and this pressure is added to the trapped annulus, increasing the pressure of trapped annulus. The final pressure is the sum of the salt pressure build up accelerated by the cooling steady state regime and geothermal pressure build up, during shutdown. The worst case scenario could be during restart the well injection, in that way, this kind of situation must be analyzed, so that it does not lead to critical situations on the casing design. Historically, according to literature review, only the annular pressure build up with production heating is analyzed. This work is a novel approach where annular pressure drop off, caused by cooling operations, was investigated including coupled salt-creeping and thermal phenomenon.
Carbonate Porosity and Permeability from Sonic Log
Authors: e Silva Fernando Gomes de Mello , Beneduzi Carlos Francisco , Nassau Gabriel Feres , Rossi Tiago de Bittencourt 
Published: October 2019

Abstract
The main goal of this work was to estimate carbonate porosity from sonic log S-wave slowness measurement, practically insensitive to fluid effect. Methodology is empirical and had already been successfully tested in sandstones (Silva and Beneduzi (2018)).
Oolitic carbonate reservoir log data were used and porosity is in good agreement with lab data. Small deviations were observed in more heterogeneous carbonate systems mainly composed by stromatolites or bivalves, being interpreted as porous geometry influence.
Compressional velocity deviation log methodology (Eberli et al., 2003) is currently used to identify porosity type in carbonates. The present rock physics model used to estimate porosity allows to define shear velocity deviations. Combination between Vp (P-wave velocity) and Vs (S-wave velocity) deviation (Vp/Vs deviation log) shows good compatibility with flow zones.
A significant linear correlation was observed between new deviation curve and the lab values, allowing calculate permeability for the entire well. Results are in good agreement with NMR log permeability. New method brings up important reservoir petrophysical information. Moreover, the results can give a very important technical support in the early stages of well evaluation.
Increasing the Attractiveness of Phased Field Development: De-Risk Reservoir Uncertainty with Efficient Field Development Solution
Authors: Basu Shiladitya , Bhaumik Tirtharaj 
Published: October 2019

Abstract
Phased Field Development (PFD) is a well-known method to mitigate reservoir uncertainty. However, by its very nature a PFD lowers the Net Present Value (NPV) of the project compared to a Full Field Development (FFD). In this work, multiple scenarios are investigated to increase the attractiveness of PFD vis-a-vis FFD. The most promising concepts are identified and their key financial characteristics are studied with a view to providing a roadmap that can assist in efficient planning of future deepwater field developments.
Annual cash flows along with revenue and profit margins are estimated and compared for the two options for a potential deepwater field development in US Gulf of Mexico.
MSE-Index: A New Concept of Energy Management to Control Salt Creep and Optimize Drilling Operations in Extensive Salt Intervals
Authors: Pinto Constantino N , Lima Angelo P , Knabe Steven P 
Published: October 2019

Abstract
Exploratory and appraisal drilling in extensive salt intervals poses a severe challenge in terms of nonproductive time (NPT) and associated costs. This paper introduces the concept of the mechanical specific energy (MSE) index for creep control in real time. This index is fundamental to leveraging an understanding of MSE behavior while drilling and managing an effective equivalent circulating density (ECD) plan.
An ECD management plan must be restricted to a salt creep operational window (SCOW) between a lower limit and a higher ECD limit. The higher limit is based on a leakoff test (LOT) or formation integrity test (FIT). The challenge in defining a SCOW is therefore assessing the lower limit because its variations with depth determine the minimum ECD. A retrospective analysis of a Brazilian presalt exploration campaign determined that, while drilling in salt layers, a direct relationship exists between creep effects (caused by insufficient ECD to stabilize the wellbore) and the behavior of applied MSE (MSEa) with depth. This relationship was analyzed to create an MSE index as a probability vs. depth matrix to help estimate the lower ECD limit during predrill planning and to make necessary adjustments to operational parameters while drilling.
This paper presents two salt creep control cases in the Brazilian pre-salt.
In the first case, drilling occurred in an extremely soluble salt environment with a high tendency to creep and cause stuck pipe. Geomechanical analysis in real time helped to control creep in the entire drilled salt interval. This analysis resulted in exceptional performance in a critically important section by eliminating five of the ten planned operational days and managing ECD within the predicted SCOW by a good safety margin.
Conversely, situations occur in both thin post-salt depositional environments and large shallow and evaporitic sections in which the SCOW does not permit creep control with a good safety margin. The second case presents specific solutions for this complex scenario, which is characterized by low LOTs/FITs, causing lost circulation and stuck pipe. In response, the authors propose that the industry adopt a new concept, the MSE index, to support the SCOW design in predrill planning and real-time operations.
The aim of this paper is to help reduce operational days, drilling risks, and costs in drilling environments with complex geopressure variations and narrow pore pressure windows by providing techniques to maintain pressure control, reduce NPT, decrease the potential for mud losses, and reduce stuck pipe events.
Comparative Analysis of Permanent P & A Requirements and Consequences in Terms of Leakage - A Case Study
Authors: Beltrán-Jiménez Katherine , Lohne Hans Petter , Ford Eric Patrick , Skadsem Hans Joakim , Lourenco de Souza Marcelo Igor , Arild Øystein 
Published: October 2019

Abstract
In South America, the discussion regarding permanent plug and abandonment (P&A) at the end of the useful life of the fields is relatively recent, but it has become increasingly important due to the maturity of certain oil fields. In Brazil, for example, the Campos, Santos and Espirito Santos Basins alone have 350 temporarily abandoned wells that should be abandoned in the coming decade. The long-term integrity of the wells once plugged and abandoned is, however, not yet considered. There is a need to perform assessments of the risk of leakage, reviewing both the probability of failure of the well barrier elements and the possible magnitude of leakage rates should one or more well barriers be compromised. This article presents a quantitative risk assessment framework that can be used to analyze the probability of barrier failure and potential consequences in terms of leakage rates. Data of a real well is used to quantify the leakage rates after a hypothetic permanent plug and abandonment operation using as reference the plug and abandonment requirements in Brazil and Norway. For both cases, the leakage paths between the reservoir and the wellhead are studied and include: the leakage through bulk cement, cracks/fractures in well barriers elements (impermeable formations, plug, and annular cement) and the presence of micro-annuli. A stochastic framework, using Monte Carlo simulations, is used to propagate uncertainty, yielding probability distributions for leakage rates. As the leakage rates are also a function of time, an analysis considering time-dependent factors such as reservoir re-pressurization is also included. The leakage scenarios for the well is presented considering the P&A requirements included in resolution N 46 (issued by the National Agency of Petroleum, Natural Gas and Biofuels (ANP) in 2016), the guidelines for the abandonment of the Brazilian Petroleum Gas and Biofuels Institute (IBP) and NORSOK D-010. Some requirements, such as plug length and barrier verification methods, are different between these two guidelines. The results are discussed in relation to the P & A requirements and the effect on the total leakage rates for each well case.
Optimization of Advanced Dual Refrigerant Expansion Cycle for Liquefaction
Authors: Kim Minki , Ryu Sijin , Lee Jongchul , Lee Donghun , Kim Mungyu , Park Hyunki , Kim Hyobin , Lee Kihwan , Kim Taeyun 
Published: October 2019

Abstract
This paper shows the sequential search algorithm that makes it possible to find the optimum operating conditions of Advanced Dual Refrigerant Expansion Cycle that is used for LNG liquefaction process. The operating conditions are key parameters in determining the overall liquefaction efficiency of system, so it is the core process to find out these optimized key parameters in LNG industries. The steps of this method are as follows. 1) Defining input variables based on understanding of liquefaction cycle and thermodynamics. 2) Setting simulation to apply the sequential search algorithm. 3) Searching sequentially several local optimum points between the upper and lower limits of several input variables considering minimum/average efficiencies and the number of points satisfied with minimum approach 4) Repeat step 3) with narrower ranges and step sizes of each input variable based on previous results. 5) Get the global (final) optimum point considering final results and realistic operation. The operating conditions of Advanced Dual Refrigerant Expansion Cycle are eventually optimized with the best overall liquefaction efficiency of system by using the sequential search method. It is directly related to economical effect in terms of the high production rate against supply power, small size of equipment and the associated pipe lines, simple system layout and so on. During searching, several local optimum points of the operating conditions can be recorded in order to compare the liquefaction efficiencies at each of points by using this method. It serves as the objective evidence to understand trends of the efficiencies calculated from variable inputs. In addition, this method can provide a variety of selecting the main equipment such as compressor, expander, heat exchanger and so on because it is possible to identify several local optimum points have similar efficiencies. This new sequential search method can be applied for the optimization of existing other gas expansion liquefaction cycles and the mixed refrigerant (MR) LNG liquefaction cycles by making adjustments to input variables e.g. MR compositions can be available input variables as well in case of MR cycles.