Day 3 Wed, August 07, 2019最新文献

{"title":"Production Optimization Strategies for Unlocking Resource Potential in A Heavy-Oil Brown Field - The OML26 Success Story","authors":"Wale Ajao, Ezinwanneakolam Isiba, Eddy Okoh, Immaculate Okoruwa, Stanley Omenai, Nicholas Abu, O. Babalola, Oluwatobi Oke","doi":"10.2118/198800-MS","DOIUrl":"https://doi.org/10.2118/198800-MS","url":null,"abstract":"\u0000 Oil Mining Lease 26 (OML 26) is held by NNPC and First Hydrocarbon Nigeria Limited (FHN) in a Joint Venture relationship and operated by an Asset Management Team (AMT). The license consists of several oil and gas discoveries including the Ogini, Isoko, and Ozoro fields on the western part, Ovo in the central area and Aboh to the east.\u0000 Oil Production is mainly from the Ogini and Isoko fields with the Ogini field contributing the largest volume. The Ogini oil is relatively heavy, with in-situ oil viscosity ranging from 3 to 59cp, and an oil gravity ranging from 15°API to 19°API. Field development and production from the Ogini field has been very challenging with the characteristic low GOR, low rate and high watercut. Oil production peaked at 8,900 stb/d shortly after field start-up in the 80s and has been declining since then.\u0000 In 2018 however, the field witnessed breakthrough performance stemming from production optimization initiatives and strategies which unlocked resource potential of the field. A peak production of ca 17,000 bopd was recorded during Q4 of 2018 without drilling new wells. A number of production enhancement activities carefully designed, planned, and executed coupled with change in operations philosophy released more volumes transforming the production levels and production profile of the field from a mere 3,000bopd to ca 17,000 bopd peak production. This paper highlights the strategies, optimization techniques and the paradigm shift in operational culture that resulted in the significant change and ramp up of production in the field.","PeriodicalId":11250,"journal":{"name":"Day 3 Wed, August 07, 2019","volume":"147 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76089828","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":"Paper Hedging Against Cyclical Crude Oil Price Fluctuations: Cost Optimization Initiatives for the Nigerian Oil & Gas Industry","authors":"J. Ugolo, Debo Fagbami, M. Iwegbu","doi":"10.2118/198808-MS","DOIUrl":"https://doi.org/10.2118/198808-MS","url":null,"abstract":"\u0000 This paper discusses the effect of crude oil price fluctuation on the personnel, projects and finances of oil & gas exploration and producing companies, as well as, the cost optimization efforts carried out during the era of lowcrude oil price. Following investigation and historical data, it is evident that crude oil price fluctuation is cyclical in nature. To make their product available for sale, oil & gas organizations, at the peak of the crude oil cycle engage in high operating-cost systems. With drastic fall in the price of the product, as experienced between July 2014 and February 2015, such organizations were faced with the challenge of continuing production at a non-profitable cost.\u0000 Crude oil price fall, have always had a big negative impact on the personnel, projects and operations of organizations in the Nigerian oil and gas industry. For personnel, the most prevalent impact was the loss of jobs, for company operations it was the reduction in revenue (income) for the companies and for projects it was the delay or cancellation of projects earlier considered profitable. These losses or delay of projects led to reduction in product portfolio and/or divestments for the organizations involved.\u0000 For the Nigerian oil and gas companies to adapt to the economic changes occasioned by the change in price, several measures have been proposed which include individual companies initiating and utilizing procedures that ensure good costing of projects, benchmarking of relevant prices and promoting good costing practices and proper management of balance sheet and adhering strongly to sustainable OPEX and CAPEX levels, to ensure opportunities are identified and utilized.\u0000 The researchers asserts that crude oil price fall with its attendant negative impact could be scientifically explained. A quantitative research methodology has been applied in the study of this topic. Using online survey, information has been gathered from respondents from six different oil and gas companies indicating their demography, individual experience, companies experience and project experience during the last crude oil price fall (2014 -2017). Secondary data obtained from historical records helped to show the influence of crude price slump on the financial health status of oil and gas exploration and producing companies. The data also helped to confirm the primary data received in the online survey.","PeriodicalId":11250,"journal":{"name":"Day 3 Wed, August 07, 2019","volume":"284 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76845183","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":"Occupational deaths from Similar Causes; Why?","authors":"G. Shittu","doi":"10.2118/198710-MS","DOIUrl":"https://doi.org/10.2118/198710-MS","url":null,"abstract":"\u0000 Understanding why incidents re-occur from similar causes despite the previous experiences, lessons and available tools to ensure that they do not happen again has been a cause of concern for company management for years and different reasons have been attributed to this issue. In recent past, below are few examples of incidents from similar causes.\u0000 On 25 January 2012, during the pre-mob inspection of a pile load tester pump by a DIL pile rig operator (Mechanical-24yrs old) with his Supervisor, the unit was put under pressure three times successfully but there was no movement of the pump piston. The pump was put under pressure the fourth time with a declared pressure of 500 bars, the pile load tester flange suddenly gave way and caused several severe injuries to the operator. He was confirmed dead at around 18h30. The unit was brand new with test certificate; IP was trained for it and note that the design pressure of the pile load tester was 690bars. In addition, when the unit failed, the 25 out of 26 bolts of the flange cut off while the last one had its nut pulled out.\u0000 On 15 May 2017, a fatal accident occurred when an analyzer engineer removed the cover on an explosion-proof enclosure as part of the routine task for the day. The ~5.5kg weighing threaded cover and with a 14 inches in diameter was propelled forcefully from the enclosure as the Engineer unscrewed it inflicting a fatal head injury. The pressure inside the enclosure from leaking sample gas or instrument air components caused the forceful propulsion of the enclosure cover. There was no gauge or indicator on the enclosure to monitor the internal pressure inside the enclosure and there was no means to relieve internal pressure (http://www.safteng.net/images/2017_Posts_Pics/CVXIndustryAlertJune2017.pdf).","PeriodicalId":11250,"journal":{"name":"Day 3 Wed, August 07, 2019","volume":"192 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73337342","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":"Horizontal Matrix Injector Stimulation in Unconsolidated Sand","authors":"A. Ekebafe, Ezeokafor Tobechukwu, Ololade T. Skaioye, Lawani Raymond","doi":"10.2118/198807-MS","DOIUrl":"https://doi.org/10.2118/198807-MS","url":null,"abstract":"\u0000 The AX field is located in Deepwater Offshore Nigeria and has been in production for ca.12 years through FPSO with a waterflood scheme providing pressure maintenance and sweep for the reservoirs. Over the years, AX field has moved from the use of deviated frac-pack injectors to horizontal SAS injectors due to significant declining injectivity observed with the deviated injectors.\u0000 The switch to horizontal injectors was premised on various studies proposing that horizontal water injectors in deep water are expected to have longer well life due to the larger flow area and ability to inject at lower flow velocities (matrix condition) compared to vertical water injectors. The benefits of going horizontal is further enhanced by keeping the well in Matrix mode for as long as possible before switching into frac mode. However, damage is inevitable afterwards, even for relatively clean injection water. This may be primarily due to various factors, one of which is fines influx into the well during abrupt shut-ins/trips from the FPSO.\u0000 AX field started operating horizontal injectors since 2011. On the average, most horiziontal injectors in AX field begin to experience injectvty decline about 1 – 2 yrs after start of injection as was the case with AX9 injector.\u0000 AX9 is a horizontal injector providing support to 2 producers in the field. Over the past four years injection had declined from 40 kbwpd to 21 kbwpd at 395 barg IBHP with II of 20 bpd/psi. This drop in the injectivity index led to a production curtailment of ca. 5 kbopd from the supported producers.\u0000 From a cross learning opportunity, it was identified that there is higher possibility of success (POS) with stimulating horizontal water injectors while still in matrix mode. Leveraging on this knowledge we decided to attempt stimulating the AX9 well for better performance.\u0000 Stimulation was carried out successfully under matrix condition using a deepwater rig in May 2018. Post stimulation, well was ramped up to 43 kbpwd at 330 barg IBHP. Increase of ca. 15 kbwpd with a corresponding 21% drop in BHP. Initial performance shows a four-fold improvement in injectivity index; current injectivity index is 80 – 100 bpd/psi.\u0000 The success of the AX9 stimulation has validated early stimulation of injectors while still in matrix mode rather than later when the well would have switched to frac mode. Additionally, the acid recipe has opened opportunities to mitigating injectivity decline in deepwater water injectors.","PeriodicalId":11250,"journal":{"name":"Day 3 Wed, August 07, 2019","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75413001","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":"The Effect of Monovalent and Divalent Ions on Biodegradable Polymers in Enhanced Oil Recovery","authors":"I. Eiroboyi, S. S. Ikiensikimama, B. Oriji, I. Okoye","doi":"10.2118/198788-MS","DOIUrl":"https://doi.org/10.2118/198788-MS","url":null,"abstract":"\u0000 The stability of polymers used in enhanced oil recovery especially in polymer flooding is largely based on their ability to withstand challenging reservoir conditions such as the effect of high salinity and high temperature. Polymers like Hydrolysed Polyacrylamide (HPAM) and its derivatives lose their viscosity when subjected to high salinity conditions due to the screening of the ions of the polymer backbone chain. HPAM is not only sensitive to salinity and temperature but also very susceptible to shear degradation. Research show that Xanthan gum; a commercial biopolymer used mostly in polymer flooding show more tolerance to shear degradation and even better stability to salinity and temperature than HPAM but not frequently used due to its high cost.\u0000 The work is centered on the study of stability of some selected low cost biopolymers like Guar gum, Locust bean gum, Gum Arabic as well as the commercial Xanthan gum. This study captures the effect of monovalent and divalent ions on the polymers in order to establish their degree of stability and the impact of these ions with respect to varying salinity conditions. The rheological performance of these polymers were analysed using both NaCl and CaCl under both medium and high saline conditions which are similar to reservoir conditions. The results show that all polymers show appreciable resistance and stability when compared to Xanthan gum especially Locust bean gum in the presence of monovalent ions, Gum Arabic displayed the least tolerance to the ions. Although, the presence of divalent ions had more impact than the monovalent ions on all polymers' stability, however, higher concentrations of the polymers resulted in more resistance to the presence of these ions.","PeriodicalId":11250,"journal":{"name":"Day 3 Wed, August 07, 2019","volume":"47 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73805478","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":"Global Warming Issues, Challenges & Vulnerable Africa – Cleaner Energy Possibilities, Emission Reduction Analysis and Mitigation Strategies","authors":"E. Umeh, Cyprian Onyekperem","doi":"10.2118/198778-MS","DOIUrl":"https://doi.org/10.2118/198778-MS","url":null,"abstract":"\u0000 This paper is intended to tackle and treat the subject of global warming which includes its components, current issues, trends and challenges to enable us to add our own mitigation measures to support the global efforts on its reduction. The caustic effects would be analyzed using environmental data gotten from Environmental Impact Assessment (EIA) studies and Environmental Evaluation Report (EER) from various field locations in the oil production fields in the Niger Delta region of Nigeria. Analysis of the various cleaner energy alternatives other than fossil fuels would be done, with individual challenges of these alternatives been highlighted, from which a projection for the zone under study would be done using graphs and data plotted in Excel. Mitigation strategies has been suggested and backed with adequate recommendations that are gotten from sample opinions from experts in environmental matters in the oil and gas industry.","PeriodicalId":11250,"journal":{"name":"Day 3 Wed, August 07, 2019","volume":"52 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83793519","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":"Logging While Drilling Cement Evaluation: Case Study in Deep Water Gulf of Guinea","authors":"Osazua J. Itua, T. Jenakumo, Mohammed Hafiz Ringim, A. D. Kuijper","doi":"10.2118/198755-MS","DOIUrl":"https://doi.org/10.2118/198755-MS","url":null,"abstract":"\u0000 Assessing well integrity through cement bond analysis is recommended and sometimes legally required because the potential risk of a poorly executed cement job on people, assets and environment during- and post well construction can be catastrophic. Traditionally, cement bond logs were acquired with wireline tools. Following advances in tool response modelling and log data processing, Logging While Drilling (LWD) acoustic data for cement bond analysis - acquiring the data while tripping in or tripping out of hole - has become an attractive and viable option to consider over traditional wireline data acquisition. The LWD option comes with the added advantage of substantial savings in rig time while eliminating operational complexity and safety risks associated with additional wireline logging operation particularly in high angle- and extended reach wells.\u0000 To assess the robustness of the LWD cased hole cement evaluation logs and to validate its application to Deep Water (DW) wells, LWD and wireline acoustic logs were acquired back-to-back in three wells in the DW Gulf of Guinea (GoG), and the bond index estimated from both acquisitions were compared. This paper presents the outcome of the work and provides support to the opportunity to consider LWD acoustic data acquisition for quantitative cement bond evaluation.","PeriodicalId":11250,"journal":{"name":"Day 3 Wed, August 07, 2019","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84916388","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":"The Application of Holistic Workflows for Sour Reservoir Management on the X Field","authors":"O. Kuku, A. Ekeigwe, G. Ajakaiye, Tammy Olushina, C. Harper, Y. Zheng, S. A. Green","doi":"10.2118/198849-MS","DOIUrl":"https://doi.org/10.2118/198849-MS","url":null,"abstract":"\u0000 The X field has been in production since 2011 and some of the reservoirs are on a water flooding-scheme for pressure support. The water flood commenced solely with the injection of seawater and more recently commingled produced water and seawater. A few years into the production, it was observed that production from at least one of the reservoirs has become sour.\u0000 Thus, a reservoir souring study of the X field was conducted to ascertain the immediate cause of souring, determine future sulphide production trend and provide recommendations on sulphide concentration and integrity monitoring, bacteria monitoring practices and mitigation against the current souring events on the X field.\u0000 The study was conducted by a joint team from Oriental Energy Resources Limited (OERL) - operator, Baker Hughes, a GE company (BHGE) in collaboration with the regulatory agency, the Department of Petroleum Resources (DPR).\u0000 The study utilized BHGE proprietary workflows, including those previously documented in SPE-179921-MS, and drew on significant routine operational data, and specialized data such as sulphide and sulphate isotopes, detailed water compositions (including Volatile Fatty Acids -VFA), serial dilution and molecular microbiological enumeration techniques and microbiological sequencing techniques.\u0000 The study concluded that the primary source of souring was microbiological and that this souring event was not limited to the focus, high H2S reservoir (XY) but was observed to be present on all water injected reservoirs in the X field. It was felt, though not proven, that the Sulphate Reducing Bacteria (SRB) may have been derived from the seawater. The microbiological Deoxyribonucleic Acid (DNA) analyses indicated that the primary carbon source, once VFA had been sufficiently depleted, was likely to be the biodegradation products of hydrocarbon degrading bacteria within the reservoir.\u0000 The study also concluded that, due to the lack of carbon source constraint for the bacteria, the required inhibitory nitrate dose rates would be uneconomically high and would yield no benefit over the effects of replacing Sea Water Injection (SWI) with Produced Water Re-Injection (PWRI). However, it has been observed that sulphate concentration in production had declined since the cessation of seawater injection.\u0000 The reservoir souring study has resulted in a heightened level of surveillance, thereby leading to a safer operating environment on the X asset. The field operating strategy and chemical application has been modified to allow the overall magnitude of sulphide related hazards and cost of operating the field to be reduced.\u0000 This project is a first in the Nigerian oil production operations, involving an open collaboration between an operator, a government body and a service vendor on reservoir souring.","PeriodicalId":11250,"journal":{"name":"Day 3 Wed, August 07, 2019","volume":"61 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84669337","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":"Evaluation of Cuttings Transport in Well Annulus Using Power Law Model","authors":"Edward K. Menegbo, Eme Charles, A. Dosunmu","doi":"10.2118/198825-MS","DOIUrl":"https://doi.org/10.2118/198825-MS","url":null,"abstract":"\u0000 The efficiency of cuttings transport is very important factor for a good drilling operation program. The transportation of these cuttings through the annulus is a complex problem that is affected by many parameters. For effective cuttings transport prediction, it will require that all these parameters be considered simultaneously. Predictions of pressure losses and cuttings transportation through the annulus are very complex during drilling operation due to the combination of interacting drilling parameters. Success during drilling program is due to efficiently cleaned hole. For better understanding of the effects of some of these parameters that affect cutting transportation, the power law of non-Newtonian viscosity model was adopted to establish the mathematical model of the cutting transport process in the well annulus. Some of the hole-cleaning challenges focused are: the absence of the basic data needed to fully evaluate present field practices and current concepts on drill cutting transport, the combined effect of operational parameters and drilling fluid properties, the effect of operational parameters and cutting properties and what is the effect of rheology model on cutting transport simulation. Poor hole-cleaning during drilling can lead to a lot of bore hole issues which has a negative effects. The overall effect is increase in drilling time and drilling cost. The proposed tool allows more precise prediction of cuttings transport property in the whole range of the well. In this paper, the effects of annular fluid velocity, transport ratio, size and density of cuttings are investigated. The results obtained showed that the most important factors controlling cutting transport are annular velocity and the fluid rheological properties. From the simulation result, it can be observed that an optimum transport ratio was obtained at 1.42m/s. The transport ratio increases rapidly with velocity but then begins to level out or increase more slowly in the velocity range of 1.42 to 1.62 m/s. We can also deduce from the result that cuttings velocity increases with the flow rate; but this increment does not follow a linear behaviour.","PeriodicalId":11250,"journal":{"name":"Day 3 Wed, August 07, 2019","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85602997","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":"Towards Information Transparency: Current Posture and Advocacy for Open Data Systems for Efficiency, Equity and Justice – The Nigerian Oil and Gas Experience","authors":"M. A. Ante, A. Ante","doi":"10.2118/198795-MS","DOIUrl":"https://doi.org/10.2118/198795-MS","url":null,"abstract":"\u0000 Transparency in information is one of the most important undertaking that the government in collaboration with oil and gas stakeholders can offer to the public. Open, and therefore, accessible, nonproprietary data in the current information age is a tool for improved governance, transparency and innovation.\u0000 The oil and gas industry is a huge data generator through its daily operations, it is a leader and in fact, a home to big data. From existing development assets, to supply chains, customer relations etc, data provides a competitive advantage for organizational growth and management. Beyond the strategic opportunities that big data provides within the industry, is the enormous capabilities that big data through open data initiatives can have on company-community relations.\u0000 In this paper, we examine the various acts and legislations governing oil and gas industry operations and their position on data transparency. Our examination sheds light on current positions of the tripartite of law, policy and practice and the demonstrated gaps between this tripartite. In addition to the legal analysis, we also examine the issue of open data through the petroleum engineering prism. The benefits and significant impact a movement in open data will deliver to the industry are also examined which include but are not limited to: addressing public concerns and increasing community workforce participation and protection of oil and non-oil natural resources.\u0000 Finally, because discussion on open data is incomplete without the necessary data literacy skills needed to utilize, analyze and draw meaningful conclusions from data, we examine how best we can increase these skills within the community to bridge the information divide.\u0000 As we enter 20 years of steady democracy and political process in Nigeria, open data will certainly disband doubts and fake news in our energy conversations as it will provide a level playing field for all parties. Public discourse will be more focused on facts and lead to improved and sound decision making.","PeriodicalId":11250,"journal":{"name":"Day 3 Wed, August 07, 2019","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80684000","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}