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Qualitative root cause assessment approach to quantify the impact of flowline internal coating disbondment

2020-01-01 , Lai H.L. , Mohd Hafiz Zakaria , Ho H.

Objective and Scope (25-74 words): During High Speed Flushing (HSF) of two water injection flowlines (WIFL) located at offshore Sabah, Malaysia at water speed of 3.0m/s, internal Fusion Bonded Epoxy (FBE) coating flakes were observed being ejected from end of flowline by ROV. There were concerns that the dis-bonded FBE flakes would block the wells during operation causing a reduction in the water injection performance. The objective of this qualitative root cause analysis is to determine the likelihood of further internal FBE coating disbondment during operation and assess whether the water injection flowlines internal FBE coating failure is localize or systemic. Systemic failure is defined as the location of the internal FBE coating disbondment has no specific pattern and is randomly distributed throughout the entire flowlines. Localize failure is defined as the failure pattern is discernible and limited to a few specific linepipe along the flowlines. Methods and procedures, process (75-100 words): The qualitative roots cause assessment of the internal FBE coating disbondment consists of the following work streams: i. Review of Shell Group past experience with internal FBE coated WIFL; ii. Review of Internal and external FBE Coating Manufacturing Record; iii. PLET's main piping video inspection; iv. Flowline in-line visual inspection; v. Laboratory testing on failed FBE flakes and internally FBE coated spare linepipe. Results, observations, conclusions (100-200 words): In conclusion, there is no evidence to suggest that the FBE disbondment in the water injection flowlines was a systemic failure or that further application of flow would cause more coating to detach from the flowlines. It is deemed that the internal FBE disbondment is high likely localized based on the following observations: • The total area of dislodged FBE coating from both the WIFLs is equivalent to approximately 30% of the internal FBE coated area of a single 12m long linepipe. • No indication that there were issues with the coating application process in factory. • The internal FBE coating application in the coating plant is a fully automated and continuous process. • Based on a review of the FBE coating manufacturing record, there is no evidence indicates that the linepipe internal FBE coating disbondment is due to external localized overheating during external FBE application. New/novel information (25-75 words): The water injection flowlines had started its operation since September 2015 and the wells performance is closely monitored by WRFM team. To date there is no decline in water injectivity being observed or reported for all water injection wells. Hence, the qualitative root cause analysis approach employed by the project team is deemed a workable analysis method in concluding the water injection flowlines internal FBE coating failure is localize and low likelihood of further disbondment during operation.

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60-year Research history of missing data: a bibliometric review on Scopus database (1960-2019)

2020-12 , Farah Adibah Adnan , Mohd Hafiz Zakaria , Safwati Ibrahim

esearch on missing data was initiatedin1960and the study on this topicgrew exponentially acrossvarioussubject areas since then.Therefore, this study aims to analyze those studies, specificallyjournal articles publishedin the context of missing data.Scopus databaseand analysis tools wereutilized to retrieve all available journal articles related tomissing dataand its data. Next, due to the large number of articles foundin the Scopus database, its informationcan only be efficiently extracted and combined using Mendeley software.To further obtained insights on the extractedinformation, VOSviewer was used to obtain network visualization and overlay visualization on authors’ keywordand citation metrics was obtained using HarzingPublish or Perish software. Additionally, the growth of publication, languages used, subject area, countriesinvolved,and publication activity were also presented using bibliometric analysis. In total, 6227journal articles werefound. The recordshows thata drastic increment of research in missing data happened in 2016, with 446publications compared to 361 in 2015. Most of the articleswere affiliated with researchers in the United States and werewritten mainly in English. Mathematics, decision sciences, medicine, and computer scienceare four subject areas that have high number of articles. It is expected that thepublications on this topic will increase significantly in 2020 due to its research trend that is currently blooming in the area of medicine and thereforeleadtopotential directions for future research

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Perspective of Construction Building Professionals on Low-Carbon Materials in Malaysia

2023-01-01 , Omar M.R. , Afizah Ayob , Mohd Hafiz Zakaria , Nur Soleha Abdul Rahim , Mokhtar H. , Rani H.A. , Rahman F.A.

Low-carbon (LC) materials and alternative technology must overcome various institutional policy and market constraints to gain greater acceptance in the construction sector. The primary impediments that must be addressed to build a viable and sustainable local construction sector are awareness and knowledge. To analyse the perspective on LC materials in the northern states of Malaysia, 93 companies were surveyed via their construction building professionals (CBPs) on awareness, usage frequency, user experience, drivers for material selection and barriers to LC material adoption in projects. To establish an understanding of CBPs and LC materials, survey data were analysed using semi-structured qualitative-quantitative approaches and the Statistical Package for the Social Sciences (SPSS), influenced by basic theory. 79.57% valid responses indicate that most participants had a low degree of awareness, with 95% confidence that there is no difference in the score levels of the overall viewpoints between architects, civil engineers and structural engineers. While unfired bricks (16.2%) are commonly and widely employed in construction projects, structural insulated panels (40.9%) are the most favourable LC materials for future projects. Client requirements, regulatory requirements and expectations of a shorter completion time are the most important factors driving CBPs to select LC materials, accounting for 44.6%, 37.8% and 37.8%, respectively. According to the CBPs, the main constraint factor to market acceptability is the “Lack of sustainable material information” (44.9%). The proposed recommendations include “Training on designing a building with LC material”, “Clear regulation on limiting carbon emission in a project” and “Increase demonstration of projects and case studies” at a rate ranging from 36.5% to 43.2% to improve client and CBPs acceptance of LC materials for a more sustainable building sector.

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Initial Results on Primary Field Cancellation of Magnetic Induction Spectroscopy Technique for Fetal Acidosis Detection using COMSOL Multiphysics

2021-11-25 , Siti Fatimah Abdul Halim , Mohd Hafiz Zakaria , Zulkarnay Zakaria , Ahmad Nasrul Norali , Anas Mohd Noor , Ahmed A.A. , Pusppanathan J. , Mohd Hafiz Fazalul Rahiman , Muji S.Z.M. , Rahim R.A.

Monitoring of fetal condition during labor could save hundred lives in a single year. During labor, fetus is at critical condition as acidosis may occur suddenly without any early symptoms. Invasive method such as Fetal Blood Sampling (FBS) has been used to detect the decline in pH level of fetus. However, fetal loss rate after FBS may range from 1.4% up to 25%. In this paper, magnetic field induction spectroscopy was implemented to determine fetal acidosis by using primary magnetic field cancellation technique. Magnetic Induction Spectroscopy (MIS) probe was design where transmitter coil (TX) is perpendicular to receiver coil (RX). The result shows that the secondary magnetic field produced have been successfully measured without any interruption from primary magnetic field. By using transmitter input 1A, it shows that voltage is inversely proportional to the blood pH due to the conductivity properties of blood.