Day 2 Wed, October 30, 2019最新文献

{"title":"Water Injection Performance Benchmarking & Replication of Best Practices Reduces Operating Cost Improves Recovery","authors":"M. Faiz, D. Mandal, R. Masoudi, Syarizan Mustapha, M. A. A. Wahab, Budi Mawardi Nasron, Sriyanta Hadi","doi":"10.2118/196475-ms","DOIUrl":"https://doi.org/10.2118/196475-ms","url":null,"abstract":"\u0000 Water injection (WI) to improve oil production and increase reserves had been practiced in Malaysia since 1990s. Currently, around 27 fields are producing with water injection. To better manage these WI fields and gauge the relative performance of these fields, certain Key Performance Area (KPA) and Key Performance Indicators (KPI) were identified. Measurement of these KPA and KPIs serves as a yardstick to compare performance of WI fields and thus provide measures to improve collective performance by promoting replication of best practices and sharing lessons learnt.\u0000 In the era of digital technology, the periodic measurement of KPA and KPI has been automated using the existing online platform which can remain accessible to all related parties. It provides a platform for data visualization with simple look forward analysis. The WI data is stored in company databank and the performance dashboard can be viewed from existing software. The team managed to overcome the challenges in completing the historical data gap and data hygiene which previously were managed manually and were not integrated. This resulted in historical evaluation of KPAs and KPIs of certain fields.\u0000 This automation initiative will enable practicing engineers to identify the value leakages and proposed mitigation efforts. Some of the best practices identified such as pipeline pigging optimization, correct biocide dosage, periodic calibration of flow meter and chemical optimization already helped to reduce operating cost in certain WI fields.\u0000 With these efforts, the company could reduce the operating cost significantly in year 2018. Other than data visualization, the tool provides diagnostic plots such as Hall Plot, Chan's Plot etc. for quick analysis of signs of well/ reservoir health deviations and thus solutions could be provided proactively. On seeing the initial positive results, this tool is being tried for the rest of the WI fields.\u0000 This paper details how this tool tries to diagnose all sub-optimal areas within various WI project simultaneously, which leads to operational excellence and improvement in oil recovery, by identifying value leakages, providing proactive solutions with replication of thus identified best practices. Additionally, usage of this tool to rank WI performance of different projects can potentially help to initiate competition between different operators for improvement.","PeriodicalId":11089,"journal":{"name":"Day 2 Wed, October 30, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81601353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First Application of Ultrasonic Technology in South East Asia: Breakthrough Case Study in Field T - Opening Doors for Alternative Stimulation Methods","authors":"C. Chang, Oliver Spenger, Amierul Amran, M. I. M. Khalil, M. H. Ariffin, D. Balakrishnan","doi":"10.2118/196508-ms","DOIUrl":"https://doi.org/10.2118/196508-ms","url":null,"abstract":"\u0000 When a well has been diagnosed with formation damage, the norm is for operators to propose reservoir stimulation via acid/solvent pumping. In Field T, located offshore Bintulu in Malaysia, mineralogy understanding is limited as cores available only represent a few reservoirs. For those reservoirs which do not possess representative cores, it is a risk to prescribe any chemical. Historically, acid and solvent stimulation do not hold a good track record in T field. Hence, it is essential seek other stimulation methods that do not involve the requirement for mineralogy.\u0000 The UST (ultrasonic stimulation) technology operates on the concept of ultrasonic waves combined with low frequency waves breaking nearby damage up to 1000m into the reservoir. The resonator is conveyed by E-line, hence, possessing a smaller footprint as compared to mobilization of a pumping unit and chemical tanks. Platforms in Field T are small, hence, bringing a pumping package onboard will require hiring a barge due to limited deck space. Seemingly, operational risks are reduced as there is no need for manual chemical handling. The selling point of this technology is minimal well downtime as the stimulation can be performed on a live well, which further reduces possibility of damaging formation during stimulation due to secondary chemical reactions.\u0000 UST was piloted on 2 wells in Field T: Well X and Y. Well X showed an initial 30% gain post stimulation. Well Y was showing signs of clogged gas lift valves. Post operation observed pressure communication between tubing and casing which suggests that UST successfully broke the wax that was clogging the gas lift valves. A takeback from this project would be to not only stimulate the target reservoir, but to also stimulate the tubing walls and gas lift valves if there are any suspected valve plugging in the well. This paper will describe the technology that was used to stimulate the well in an environmentally friendly, non-invasive method. For fields with limited mineralogy data and deck space, it is recommended to explore an alternative stimulation method, such as UST, on the wells.","PeriodicalId":11089,"journal":{"name":"Day 2 Wed, October 30, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72708713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prediction of Wettability Alteration Using the Artificial Neural Networks in the Salinity Control of Water Injection in Carbonate Reservoirs","authors":"Leonardo Fonseca Reginato, C. C. Carneiro, R. Gioria, M. Pinto","doi":"10.4043/29916-ms","DOIUrl":"https://doi.org/10.4043/29916-ms","url":null,"abstract":"\u0000 Artificial Neural Networks (ANN) applications have grown exponentially in all areas of science and technology. The advantages are its versatility, speed and ability to aggregate information, perform predictions of a given set of data. These attributes attract the petroleum industry, which often depends on laboratory analysis or numerical simulation to estimate various reservoir behaviors. This research, aims to predict the relative permeability curves with wettability alteration effect, given a concentration of the ionic composition in water injection. For this, machine learning methods were applied. An analytical algorithm was developed that incorporated the effect of wettability alteration, generating the database for the training process. Two different networks were applied: (i) Self-Organizing Maps - SOM and (ii) Neural Net Fitting – NNF. The forecast data of the networks are compared with calculated for analytical results. This ANN performs a good forecast of data tested (NNF with R-squared results around 90%). The analyses confirm effects on relative permeability of oil and water with salt control, indicating wettability alteration (WA). These tests were able to confirm that the applied methodology is capable to predict, using ANN, results of several laboratory tests.","PeriodicalId":11089,"journal":{"name":"Day 2 Wed, October 30, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85615814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Implementation of a Two-Phase Simulator Based on the Brinkman's Equation for Vuggy-Karstified Reservoirs","authors":"D. Hallack, J. S. A. C. Filho, P. Couto","doi":"10.4043/29776-ms","DOIUrl":"https://doi.org/10.4043/29776-ms","url":null,"abstract":"\u0000 Due to the chemically active nature of carbonates rocks they are highly susceptible to the phenomenon of rock dissolution, a diagenetic process by which minerals are dissolved and removed by the fluid that fills the porous space creating and modifying the porous medium. This phenomenon might occur in small and medium proportions generating the so-called vugs, regions with pore volumes orders of magnitude greater than the conventional intergranular spaces. The dissolutions might also occur in much larger scales, generating extensive networks of caves. The validity of Darcy's flow equation to model flow in vuggy-karstified petroleum reservoirs can be questionable since viscous stresses of the fluid are not contemplated. The Brinkman equation can be a more general approach to model the flow in the presence of both: open spaces and porous media, even though not commonly used in hydrocarbon (HC) flow problems. The importance of understanding and modeling viscous fluid stresses in HC flow is highlighted by the fact that commercial reservoir simulators do not contemplate such effects.\u0000 In this work, we developed a numerical simulator able to represent the single and two-phase flow (water-oil) using both Darcy and Brinkman equations. Equations were discretized using a finite difference method (FDM) and solved using the IMPES formulation. The simulator was verified against representative cases of 1D and 2D reservoirs submitted to water injection. Results from both equations are compared in terms of the velocity field, water saturation front, recovery factor, and water breakthrough in the producing well. In our results, we observe significant differences between the Brinkman and Darcy formulations when higher orders of permeabilities are attributed to high porosity media. Regions with high porosity (attributed to the karstified region) presented worse areal sweep efficiency and better displacement efficiency when the flow is modeled by Brinkman's equation. No influence of Brinkman's viscous term on conventional porous media is observed. This work shows that the Brinkman-based simulator is able to couple the use of Darcy's formulation in regions with low Darcy numbers (Da) (conventional reservoirs) and the use of Stokes' formulation in regions with high Da numbers (regions of intense karstification).","PeriodicalId":11089,"journal":{"name":"Day 2 Wed, October 30, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84602097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Subsea Induction Heating Technology Solves Hydrate and Wax Issues in Subsea Flowlines","authors":"S. Anres, R. Hallot, T. Valdenaire, L. Macauley","doi":"10.4043/29724-ms","DOIUrl":"https://doi.org/10.4043/29724-ms","url":null,"abstract":"\u0000 A new technology called local heating offers the possibility of significantly raising the temperature of the multiphase production fluid in order to improve flow assurance and consequently the economics of field developments. Heating the flowlines is a way to overcome the thermal constraints, mitigate hydrate & wax risks and provide operational flexibility. Indeed, in the case of long distance tie-backs, very deepwater applications or when the fluid temperature at the wellhead is too low, conventional flow assurance solutions might be very expensive or even not applicable.\u0000 While other heating technologies such as DEH and Heat tracing are only used under transient operations (start-up, shutdown, preservation), local heating is a different solution, mainly to be used continuously during production and also during transient operations as long as there is fluid circulation in the flowline. The local heating device is a very simple and robust system integrated into a compact subsea module, installed in parallel of the main flowline and which can be retrieved for maintenance or relocated. The technology is compatible with any type of field architecture and can be implemented either on greenfields or brownfields. In the case of greenfields, the use of local heating is a way to mitigate uncertainties on production fluid temperature or solve an unexpected poor thermal performance of the design.\u0000 The main principles of the local heating technology, as well as a preliminary design performed for a specific case provided by an operator, will be described in the paper. This solution is based on induction and is therefore able to provide very high-power levels (several MW) with a compact module. The temperature is continuously monitored throughout the heating module by means of fiber optic distributed sensors. The technology is fully compatible with preservation by flushing and allows pigging in the event of deposits.\u0000 The paper will also present the qualification work performed by Saipem to date including heating performance tests performed mid-2018 on a small-scale submerged prototype operated under atmospheric conditions with multiphase fluid. The tests have confirmed the good electrical and thermal behaviour of the system.\u0000 The next qualification step entails new tests to be performed on a medium scale prototype using crude oil as process fluid. The main objective is to qualify the heating performance tests and the fabrication method of the local heating module under representative conditions: representative process fluid and representative module geometry. The intention is to perform these tests on an existing Brazilian onshore test site in the frame of a JIP.","PeriodicalId":11089,"journal":{"name":"Day 2 Wed, October 30, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82391430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Novel Application of Production Acceptance Testing in the Development of Intelligent Well Completion Equipment used in HPHT Applications","authors":"A. Balasubramanian, M. Christie, P. Shrivastava","doi":"10.4043/29729-ms","DOIUrl":"https://doi.org/10.4043/29729-ms","url":null,"abstract":"\u0000 The successful operation of completion tools, especially intelligent completion tools, at high pressure/high temperature (HPHT) operating conditions is dependent on reliable design and robust production and operating procedures. Recent technological advancements in high-temperature electronics can lead to changes in the production processes of existing completion products. Possible reasons for change include component obsolescence, consolidation of production processes, or leveraging technological advancements from one product to another. Verification of changes made in production processes is critical to maintain high operational reliability of the product. This paper presents a methodical test design approach to verify changes made in production processes in a cost- and time-efficient manner.\u0000 The purpose of the Production Acceptance Test (PAT) is to provide assurance that the reliability of standard production items meets the reliability specifications. PAT usually involves testing of a sample of items drawn from a production batch. The results obtained from testing these samples enables an informed decision regarding the reliability of the entire production population. The concept and philosophy of PAT stems from the military handbook, MIL-HDBK-781, based on non-parametric distribution utilizing Mean-Time-Between-Failures (MTBF) as the performance criteria. To overcome the limitations of MTBF and non-parametric distribution, a modified test design methodology includes a comprehensive reliability statement of the product along with the use of parametric cumulative binomial distribution. Elements of PAT design (Discrimination Ratio (DR), producer's risk, consumer's risk, etc.) are assessed for developing high-temperature electronics for HPHT environments.\u0000 A key prerequisite of employing PAT is to assess product reliability through either reliability test data or field operational data. A reliability specification of the product is an upfront requirement of designing PAT. The test design methodology presented utilizes comprehensive reliability statements in terms of % probability of success, % confidence, lifetime, and operating conditions. DR is another key element of PAT design and typically ranges from 1.5-3.0. However, for manufacturers with robust production processes and well planned management-of-change, DR lies somewhere in the range of 2.5-3.0. By selecting optimum values of test design parameters, an effective test plan can be developed which can result in time and cost savings compared to a standard reliability test.\u0000 This paper discusses the methodology and application requirements to enhance PAT as a verification test to validate any changes in production processes. Test design methodologies are upgraded to include a comprehensive reliability statement along with the use of a parametric cumulative binomial algorithm to overcome the limitations of original PAT methodology highlighted in MIL-HDBK-781. Optimum value assessment of PA","PeriodicalId":11089,"journal":{"name":"Day 2 Wed, October 30, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87156542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How Repeatable will Libra Pre-Salt PRM Permanent Reservoir Monitoring be ? A Full Wave Elastic and Acoustic Study","authors":"C. Déplanté, R. Sansonowski, D. Garcia, Bernardo Radefeld Mereilles, Mônica Maria Muzzette da Costa, R. Dias","doi":"10.4043/29805-ms","DOIUrl":"https://doi.org/10.4043/29805-ms","url":null,"abstract":"\u0000 Mero (Libra NW) is a field with high Gas Oil Rate (GOR) and high CO2 content, therefore the produced gas is reinjected in the reservoirs and the reservoir management strategy revolved around mitigating gas to maximize oil production within the limitations of surface gas reinjection capability. The reservoirs are thick but present 4 orders of magnitude in the variations of permeability (Fig. 1 left), including presence of high porosity/high permeability units that we anticipate will channel part of the gas injection, but are generally impossible to map from 3D seismic.\u0000 The production strategy put in place by Libra Join Project Team (JPT) to address this setting combines several technologies that combine together with others such as HiSep CO2 separation:\u0000 An injection strategy combining Water Alternating Gas (WAG) to slow the gas, with injection of gas into the most porous parts of aquifers in order to delay the increase of GOR around the producers.\u0000 The use of intelligent well completions with several levels that can be de-activated in order to limit the amount of gas injected or produced in various zones.\u0000 A monitoring strategy combining the usage of tracers with high-quality 4D in order to detect and track the gas fronts.\u0000 Firstly, combining the two first strategies should provide efficiency in reactive reservoir management, adressing the risks induced by locally strong values of respectively high horizontal (Kh) or vertical (Kv) permeability (Fig. 1 right).","PeriodicalId":11089,"journal":{"name":"Day 2 Wed, October 30, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85358745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimizing the Separation Process in Floating Facilities : The Wash Tank Oil Processing Technology","authors":"D. Thierens, P. Pedenaud","doi":"10.4043/29811-ms","DOIUrl":"https://doi.org/10.4043/29811-ms","url":null,"abstract":"\u0000 This paper describes Total's patented wash tank oil processing system, now globally licensed to Sulzer 1, which optimizes the water-from-oil separation by relocating part of the process from the FPSO's topsides to specifically designed hull tanks while eliminating the need for electrostatic coalescers and/or desalters. As a result, this technology reduces the topsides oil processing system weight, complexity and CAPEX. Sulzer's patented inlet distributors and static mixers are key building blocks to achieving the performance required.\u0000 The technology principles, both from a theoretical and a qualification view, as well as selected operational feedback from the FPSO's which are currently using this system are covered. The proper functioning of the wash tank system relies on the controlled creation of a dense packed zone (DPZ), which consists of a layer of dense droplets located between the water layer and the oil layer which acts as efficient water droplet coalescence promotor to allow gravity to separate these enlarged water droplets from the outlet oil. The behavior of the DPZ and its impact on the water-from-oil separation efficiency is experimentally verified in a wash tank pilot system which operates with actual field oil samples to ensure the full scale production unit will achieve the performance required. The water-from-oil separation efficiency observed at the FPSO's in operation meets typical industry standards for oil export of 0,5 % BS&W (basic sediment & water), while matching with design model predictions and pilot testing results. This is achieved with simplified process topsides and without the use of electrostatic coalescers/desalters and/or excessive heat input to reduce oil viscosity. Because of the large holdup volume and residence time within the wash tanks, the system shows a robust performance and extensive flexibility towards production flow rate variations.\u0000 The wash tank oil processing system has demonstrated its separation performance on a total of 5 FPSO's & FPU's currently in operation and can thus be considered a reliable and robust technology. Through the license agreement between Total and Sulzer, this technology is now available for the entire oil processing community for deployment on new-build FPSO's, FPU's or PSO's and converted tankers.","PeriodicalId":11089,"journal":{"name":"Day 2 Wed, October 30, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81763701","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Libra Digital: An Integrated View","authors":"Flavia Pacheco Teixeira da Silva, S. Anjos, A. Ferreira, O. Wambersie, Daniela Gonçalves Moura, Luciana Frechette Pinheiro, Bruno Evione Santos, Thais Eleuterio R. Oliveira","doi":"10.4043/29953-ms","DOIUrl":"https://doi.org/10.4043/29953-ms","url":null,"abstract":"\u0000 Digital transformation has revolutionized the way companies operate in the market, changing their work processes with the inclusion of new technologies and thus influencing their culture. In the oil and gas industry, this phenomenon is more recent and is increasingly accentuating. Its importance is such that companies are adjusting their structure to accelerate the implementation of this new culture.\u0000 At Petrobras this movement was no different, the corporate area responsible for the digital transformation in the company orchestrates this movement, identifying new opportunities, coordinating corporate initiatives and following the fronts already being implemented in other areas, ensuring alignment with institutional guidelines.\u0000 Libr@Digital program aligned with Petrobras’ Digital Transformation corporate initiative and it has been working as a testing environment to validate the solutions before scaling them up to Petrobras operations. This is so, because Libra in its structe congragates all disciplines that integrate the E&P activities, from exploration to oil offloading.","PeriodicalId":11089,"journal":{"name":"Day 2 Wed, October 30, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81852532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New Compact Gas Dehydration Technology","authors":"B. Neumann, Tor Olav Seltveit","doi":"10.4043/29810-ms","DOIUrl":"https://doi.org/10.4043/29810-ms","url":null,"abstract":"\u0000 Drying natural Gas must be done to prevent corrosion and deterioration to the export/transport piping and equipment.\u0000 Today, the most common way of dehydrating Gas is by Tall and heavy contactor tower units. Contactor tower are sensitive to movements and not possible to install subsea. The towers take up valuable topside space, and today space and weight is limited.\u0000 New Compact DryGas is an all new technology for Gas-Dehydration where Company utilize its competence, experience and the field prooven «Company Technology». This will give the Client Low height and weight, smaller and cheaper units with Flexible installation and independant of movement. Company DryGas can reduce TEG circulation rate at higher pressure / lower temperature. The Compamy are probably! the only gas de-hydration technology capable for subsea installation (today)!","PeriodicalId":11089,"journal":{"name":"Day 2 Wed, October 30, 2019","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82774622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}