bluuebunny/crossref_metadata_2025 huggingface dataset:
Recent Active Heating Breakthrough and New Opportunities for Deepwater Tie-Back
Authors: Suhaimi Radzlan Ahmad , Michel Xavier , Roux Arnaud , Minier Yves , Reboul Pierre
Published: February 2024

Given the sustained oil and gas demand, there is a constant trend among oil and gas companies to develop new prospects and maintain the current production level. This trend is paralleled by an increased focus on innovative technological solutions aimed at accessing more demanding, remote, and deepwater hydrocarbon reservoirs, primarily driven by the diminishing output from shallow water brownfields. These reservoirs can present fluid properties challenges, including high wax and hydrate content. This gives rise to flow assurance challenges, which, in turn, have repercussions on production costs, potentially rendering the development of such fields economically unviable through conventional methods.

Following years of technology development, Electrically Heat-Traced Flowline (EHTF®) is the advanced heating technology equipped to tackle these flow assurance challenges. This technology reached a key milestone in 2022 - demonstrated performance in service (TRL 6). The test protocol exhibited live production and shutdown situation, during which active heating was successfully switched on. The successful completion of the in-service performance test of the first commercial EHTF®, combined with subsequent delivery and installation of similar product, has changed the profile of active heating solutions for subsea tie-back.

The first part of the paper shall delve into the fundamental scientific principles behind EHTF®. Subsequently, the paper will explore on the recent successes in the installation of the EHTF®, from the initial product development, subsequent design and qualification stages, through fabrication, installation, and eventually commissioning of the subsea tie-back.

The next section will examine EHTF®’s track records on various projects, how performant is the technology during operations, and how fit-for-purpose configuration is recommended when developing active heating system for specific field developments. This part will discuss the EHTF® product portfolio, the corresponding envelope of application to cater for multiple fluid challenges and tie-back distances as well as its Technology Readiness Level (TRL).

The paper will then present a description how the EHTF® can be tailored to meet specific field application needs, expanding its potential usage. To provide a wider perspective on the EHTF®, we will present a qualitative comparison with the alternative active heating solution, the Direct Electrical Heating (DEH) solution. In the last section a typical EHTF® tie-back will be presented, in the context of deepwater field in the South China Sea prior to concluding the paper.
Challenges in Integrity Assessment of TMCP Pipeline Girth Welds in Severe Sour Service
Authors: Prakash V. , Gomez K. B. , Fisol A. C.
Published: February 2024

In recent years, the number of developed gas and oil fields with an increased content of hydrogen sulphide is increasing. Metallic materials such as carbon steel and weldments can become brittle and crack in sour environments due to a combination of chemical, physical and electrochemical factors. Following the industry experience with premature failure of Thermo-mechanically Controlled Process (TMCP) steel pipes handling sour gas, stringent requirements have been established for integrity assessment of linepipe longitudinal seam and girth welds. Commonly used reference is DNV-RP-F108 with certain project specifications from operators. This paper identifies the gaps and potential conservatisms from multi-disciplinary inputs used for integrity assessment using fracture mechanics, commonly referred as Engineering Criticality Assessment (ECA). This work also briefly elucidates the resulting fabrication challenges associated with a stringent girth weld acceptance criterion.

Integrity assessments of flaws in pipeline system girth welds is typically performed based on a fitness for purpose approach using fracture mechanics principles. Commonly used standards are DNV-RP-F108 and BS7910 for pipelines and risers. Parametric fatigue and fracture assessments have been performed using Crackwise software. These results have further been compared with crack driving force from the Finite Element Analysis software, ABAQUS. Solid 3D FE modelling and assessment of crack driving force for fracture has been performed by evaluating the J-integral.

The influence of key parameters such as fatigue and fracture characterization of parent pipe and girth weld, associated loading, weld geometry, and Non-Destructive Evaluation (NDE) inspection accuracy has been discussed. Potential impact to welding acceptance criteria, associated inspection challenges, and risks to overall project schedule has been discussed. Gaps to DNV-RP-F108 have also been identified and potential solutions recommended.

This paper provides a holistic view based on recent experiences in sour service application that can be used as basis for revising DNV-RP-F108 for integrity assessment of girth welds. It can be used as a basis for standardization of sour service tests. This work is of interest to stakeholders, including field owners, EPCI contractors, standardization committees and consultants.
Challenges and Solutions for Deep water Subsea Pipeline Design: A Case Study on Chinese Longest Distance Multiphase Pipeline Tie-Back in LS25-1 Project in South China Sea
Authors: Zhang Ying , Xiong Hairong , Li Xu , Ma Kunming , Wang Leqin , Wang Lin , Wang Bo , Ren Cuiqing
Published: February 2024

The Lingshui25-1 gas field is located in the northern sea area of Qiongdongnan Basin, and the water depth is 850m ~ 1000m. The gas production from the LS25-1 field is facilitated through a 115 km long, 20-inch export pipeline, which ties back to a shallow jacket platform. This paper delineates the design and analytical approaches employed for the 20-inch export multiphase pipeline, addressing significant design and installation challenges. These include pipeline route optimization, pipe-soil interaction analysis, bottom roughness and span fatigue analysis, and a composite fatigue assessment encompassing VIV span fatigue, thermal fatigue, and slugging fatigue at subsea scarp locations. As of October 2023, the pipeline has been successfully laid, accompanied by subsequent post-installation surveys. This paper additionally elucidates the installation processes and post-survey span conditions, contextualized within the realm of subsea engineering.
World's First Fishbone Openhole Gravel Packing Using Shunted Gravel-Pack System: A Case History from Bohai Bay, China
Authors: Wei Min , Cun Xi Hong , Liu Yaolan , Teoh Melissa , Moses Nicholas , Zhao Geng , Liu Xiao Li , Ren Xiaoqiang , Zhang Yong , Hua Jing
Published: February 2024

For the first time in China, shunted gravel-pack screens have been used for two long, fishbone type, multilateral openhole sand control wells in 2022. Shunt-tube systems have been widely used in cased hole and openhole gravel-packing operations in the past few decades as the most reliable sand control solution. However, this is the first shunted gravel-pack screen application in an openhole main bore with fishbones. This successful drilling and completion methodology can be used in this field and other locations to increase the well production rate by enlarging the reservoir contact area with fishbones without adding much capex to drilling and completion operations.

Challenges and solutions for two wells included running the completion tool string to total depth in complicated well configurations, optimized operating procedures, gravel-pack pumping design for complicated scenarios resulting from fishbones, and onsite operations. The work included a detailed analysis of post-job data.

The uncertainties of fluid loss and wellbore stability around the fishbones and the potentially unstable shale streaks in the 600-m-long openhole sections became challenging during gravel packing. Bridging was observed when slurry arrived at the openhole, and shunt tubes were activated much earlier than expected for both wells. Most (85%) of the packing was pumped through shunt tubes for the first well. High wellhead pressure caused by shunt friction was well managed to make sure as much gravel as possible was pumped. For the second well, 67% of the packing was pumped through shunt tubes.

As there were no bottomhole gauges ran on wash pipes, post-job analysis was mainly based on volumetric data to analyze the potential packing sequence for the two wells. Post-job data analysis indicated that early gravel bridging might be attributed to potential hole collapses around the lateral and shale sections. Without the use of alternate shunt-tube screens and proper carrier fluid, the job would likely have resulted in an incomplete packing and failed sand control operation. Packing efficiency was 123% and 146%, respectively for the two wells, and the oil production rate was two times higher than that expected.
Directional Drilling and Logging While Drilling Operation Optimization Methods in a Brownfield-Fast-Drilling Environment
Authors: Andoni B. , Wiharja A. , Yudhatama M. , Pratama A. , Haramain H. , Noviasta B. , Taufik E. , Karnadhi G. , Wijayanto T. , Murti K. W.
Published: February 2024

Delta Mahakam, located in East Kalimantan has been known as one of the old oil and gas fields in Indonesia which has been developed since 1970. With massive production over more than 50 years, the field has entered the brownfield period. The reservoir pockets get more difficult and challenging to reach. The environment is factory-drilling with a fast operation (up to 200 m/h instantaneous on-bottom penetration rate, multiple offline activities, and fast connections practices) and is considered to be reaching the saturation level. The challenge now is to identify the opportunity for marginal but continuous performance improvement to lower the overall drilling operation cost.

Specific to this Delta Mahakam brownfield, there are at least six (6) DD/MWD/LWD-related initiatives that were implemented to optimize the drilling operation: (1) Adaptive and Continuous development of drill bit design; (2) Robust metal-to-metal-based push-the-bit Rotary Steerable System (RSS) utilization to boost up ROP; (3) Downhole steerable motor with high torque performance power section to gain higher horsepower during drilling; (4) High-performance motorized RSS to improve performance in S-type high torque, interbedded high impact formation, and long reach wells; (5) Utilization of LWD tool with single co-located formation evaluation sensors to enhance safety, surface handling efficiency, and geo-stopping; (6) high-resolution real-time data for high-speed drilling and safe BHA pull out of hole (POOH). For the last 5 years, despite the more challenging oil/gas reservoir pockets to be targeted, the directional and logging while drilling performance in Delta Mahakam continuously increased. The drilling statistics show that 19.5% higher on-bottom ROP has been achieved by transitioning the BHA drive system from an elastomer-based to a metal-to-metal-based push-the-bit RSS system. For wells with a steerable motor application (high DLS requirement in wash-out prone zone), the high-torque performance motor helped boost up sliding ROP, improving the total drilling on-bottom ROP by 24%. For the wells with special challenges (S-type high torque, interbedded high impact formation, long reach), the high-performance motorized RSS has proven to achieve 39% higher on-bottom ROP, which potentially saved 175 hours of drilling time from 7 wells drilled compared to the traditional RSS-standalone approach. On the invisible lost time (ILT) reduction side, the utilization of an integrated single-collar LWD tool saved the surface handling time by an average of 34%, and TD determination by 43%. All those performance improvements are achieved without sacrificing the real-time data quality supported by the high-frequency mud telemetry technology which transmits the signal 200% faster than the average technology available in the industry.
Reducing Red Zone Entries and Rig Time with Fewer Slip Changes for Drilling and Casing Operations
Authors: Angelle Jeremy R. , Thibodeaux Robert L. , Smith Logan E.
Published: February 2024

The construction of wells in deepwater environments is accelerating toward a common goal of reducing the personnel required to construct wells and reducing or eliminating entry and working in hazardous zones which commonly existing around well center. Due to its repetitive nature, tubular installations are often viewed as an attractive focus to mechanize or automate. Within these operations an area often overlooked is the rig up, change out, and/or rig down of tubular installation equipment.

Deepwater well construction requires casing strings to be installed in the well by utilizing a drill pipe landing string. While this is common practice, it is a practice that introduces risk as handling tools are required to be changed out during the switch over from casing to drill pipe which requires multiple personnel operating in the red zone. This risk is also present when casing strings of varying diameters are installed which gives the well architecture additional clearance down hole. Additionally, tripping operations also contain multiple components the BHA and varying diameters of drill pipe requiring multiple slip changes.

While tool changeout is common and varies throughout the well construction process, one specific example that is commonly found in deepwater well designs are production tie-backs. They are often tapered with the top section of the casing string being a larger diameter than the bottom section to allow clearance for critical components contained within the completion string such as subsurface safety valves. Currently, to safely execute the installation of a production tie-back string, two slip system changes are needed as operations moved from the bottom section of casing string to the upper section of casing string and then to the drill pipe landing string. In this case, installation requires more equipment present on the rig, increased rig time due to the multiple slip changes, and increased safety risks as additional red zone entries are required to swap out slip systems. Additional examples include drill strings that contain components within the bottom hole assembly (BHA) that vary in diameter. This operation contains the same safety risks and inefficiencies as the previous example.

A novel slip system has been implemented that reduces the number of slip changeouts improving safety on the rig floor and decreasing rig time.
Enhancing Sand Management in Gas Field A: Integration of Acoustic Sand Monitoring with Online Sand Sampling for Improved Sand and Fines Detection
Authors: Simatupang Athur R. , Ambrose Jonathan L. , Ramli Mazlan , Ragunathan Thevaruban , Muslim Abdullah , Harahap Riza A. , Nurrahman Fahmi , Natanagara Bayu B. , Tanjung Erwindo , Satiawarman Anugerah
Published: February 2024

Acoustic Sand Monitoring (ASM) is currently used to detect and monitor the presence of sand particles in flowlines, however its effectiveness in detecting fine sand particles is limited due to the small size, lower impact energy, and tendency of the minute grains to remain suspended and not impacting the inner pipe surfaces. Quite frequently, flowlines produce external noises due to slugging and flowline pressure which can be misinterpreted as sand production on ASM graphs. This paper explores the combination of online sand sampling with acoustic sand monitoring in Field A, Indonesia, to improve sand production detection for sand production in gas wells in order to safeguard asset integrity and enhance production. A comparative analysis of utilizing the combined technology was performed aiming to shed light on the efficacy of combining both sand monitoring techniques. It was concluded that the combined approach of the acoustic sand monitoring with an online sand sampler is crucial for a comprehensive assessment of sand production, particularly in capturing finer sands to allow operators to determine their safe operating envelopes.
Engineered Scrubbing Fiber in Cement Spacer Improves Mud Removal
Authors: Persaud Aniesa , Munoz Moises , Kapoor Saurabh
Published: February 2024

Nonaqueous fluids (NAF) are widely used in offshore Guyana drilling operations. NAF are incompatible with all slurries because they affect properties such as thickening-time and compressive strength, in an unpredictable manner. Spacers are used to clean the mud on the borehole wall by water wetting; thus, reducing the mud on the wall risk by separating the mud from the cement in the casing and annulus to help acquire good cement bonding. Solids in the spacer increases the cleaning efficiency of mud on the wall. An engineered scrubbing fiber, presented in this paper, is added in the cement spacer to enhance its cleaning property by providing a scrubbing effect. This fiber removes the mud from the casing or formation by attracting the nonaqueous compound toward itself by a hydrophobic-hydrophobic interaction. The scrubbing fiber is applicable in all cement spacer applications and can be tailored to the job conditions once within its operating limits of density, temperature, and concentration. The cement spacer, with the engineered scrubbing fibers, is designed by following a sequence of laboratory tests, gathering the well and conventional cement spacer information. Laboratory testing was performed for the implementation of the scrubbing fiber in the cement spacer to confirm its performance with drilling fluid used in the Guyana operations. From comparative laboratory results, the engineered fibers at 1.5 lbm/bbl concentration in the cement spacer did not have any significant effect on cement spacer or cement slurry when compared with a cement spacer containing no fibers. The fibers, together with mutual solvent and surfactants, have been evaluated for mud removal efficiency and showed their ability to increase the cleaning efficiency as much as 93% mud removal. The best method to add the fibers to the cement spacer was also analyzed and was successfully performed during the mixing of the cement spacer on the rig and by being delivered to the well. The major benefits to the client by using engineered scrubbing fibers in the cement spacer are to improve cement bonding once in place (Eulberg and Hudson 2017) and in the case of plug cementing and liner operation, to reduce the risk of set cement in the drillpipe (Edwards et al. 2013) during pulling out of hole operations. The improved mud removal achieved by using engineered scrubbing fiber in the spacer has proven successful through laboratory tests, including cleaning efficiency. Field application of the fibers in the spacer increases the chances for successful zonal isolation and meeting a client's objectives.
Challenges and Opportunity in Delivering Low-Cost Solution to Re-Purpose Existing Pipeline into CO2 Service for CCUS Project
Authors: Karim K. A , Hussien H. , Koi S. W , Yusof N. A , Bahar F. W Ahmad , Talik H. Abedul
Published: February 2024

Re-qualification, conversion, and utilization of old existing pipeline to become CO2 pipeline based on DNV-RP-F104 become one of attractive opportunity to reduce overall CCUS CAPEX compared to laying a new CO2 pipeline. However, it comes with various technical challenges includes flow assurance, integrity status of the existing pipeline i.e. current condition of the pipeline, including limitation of existing pipeline material strength and corrosion due to overdue usage. Pipeline materials are expected to be able to resist rapid de-compression force thus preventing running ductile fracture (RDF) to happen. To also note that existing pipeline are generally corroded based on latest available in-line inspection outcome.

A comprehensive technical assessment followed by commercial assessment shall be performed in determining technical suitability of existing pipeline that to be converted into CO2 services. As a start, a study on pipeline fit-for-service (FFS) shall be performed to determine the remaining life of pipeline based on remaining wall thickness. A numerous iteration using Enhanced Battelle Two-Curve Method (e-BTCM) shall be performed for the entire length of pipeline which may comprised of various pipeline wall thickness and design specification. On top of that, process flow assurance simulation study shall be conducted in determining design and operating envelopes of the new CO2 flow regime for optimum and safe transportation of CO2 from gathering system to offshore injection reservoir. Additionally, corrosion assessment shall be performed to calculate the corrosion rate based on fluid composition and impurities thus predict remaining life of pipeline with CO2 services.

A study of 155km total length of existing pipeline is having some limitations for the conversion of the whole pipeline system to flow with CO2. One of the limitations is the first 10km of pipeline is not meeting RDF requirements. The attractive solution of the conversion whereby most of the pipeline length still can be used, while first 10km length will undergo pipeline rehabilitation such as pipeline clamping, pipeline sleeving or sectional replacement. It is observed that pipeline rehabilitation solutions play a major part in reducing total CAPEX for CO2 pipeline re-purpose. This paper will further define the challenges and resolution in delivering a low-cost solution for pipeline re-purpose in comparison to laying a ‘new’ pipeline.

Detailed assessment using e-BTCM in determining the required toughness of line pipe materials as well as optimum departing temperature has resulted in low-cost solution for CO2 pipeline re-purpose CCUS project.
A Novel Hybrid CO2 Capture System from the Atmosphere (DAC)
Authors: Wood C. , Aryana A.
Published: February 2024

The global energy transition has intensified the search for effective carbon capture and storage (CCS) methods, emphasizing the urgent need to combat climate change. Among these methods, direct air capture (DAC) has emerged as a crucial area of research due to its potential for removing carbon dioxide (CO2) from the atmosphere. However, existing DAC processes face challenges such as high energy consumption and cost, primarily stemming from the low concentration of CO2 in ambient air. This presentation introduces, an innovative capture technology designed to overcome these challenges. At its core, the terchnology incorporates a novel hybrid sorbent that combines the strengths of both liquids and solids (called liquid amine particles, LAPs), resulting in superior performance compared to traditional carbon capture technologies. This presentation provides an overview of the development and current status of this technology, highlighting its potential to achieve the lowest levelized cost of capture.
Integrated Modelling Solutions for Flow Assurance and Process Dynamics Using Physics and Data
Authors: Easwar R. , Kowta R. , Wadia N. , Thornett S.
Published: February 2024

Flow Assurance and Process solutions are the key drivers for design and efficient operation in terms of maintaining system integrity and profitability. Subsea and Export systems rely on modelling multiphase thermodynamic calculations for design and real-time monitoring systems. Topsides and Onshore systems require modelling of unit operations, control schemes and equipment specific operating envelopes. Due to these vastly different requirements, the oil and gas (O&G) industry relies on different software/ tools to understand flow assurance vs process conditions. Achieving a solution that provides a holistic perspective helps in preventing individual system contractor oversight, in understanding how individual system designs operate and fit together, in supporting integrated procedures development/verification, and can act as an operator training simulator (OTS) system.

A fully integrated process digital twin with both physics based and digital capabilities is required to achieve the above objective. The Integrated Dynamic Model (IDM) uses physics based hydraulic and thermophysical calculations in the design phase to inform integrated system responses that drive design decisions. In the operate phase, the IDM uses the field sensor data in real-time to monitor the field, trigger alarms/alerts for specific events, identify process anomalies like leaks and restrictions, assess hydrate formation potential and provide predictive functionalities to determine system states based on an operator action.

Transient events can trigger responses across system interfaces and may lead to hydrocarbon release into the atmosphere, production losses and system integrity/safety issues. The IDM helps in complete process digitalization, field operation verification, process optimisation, decarbonization and improving system integrity. With the utilization of the historical field data, the IDMs are further able to learn and understand field-specific nuances that further supports operator readiness.

The IDM is novel to the industry due to its capability to use production analysis data, equipment operating envelopes, control logic sequences and field data in real-time to provide informed decisions for integrated system design and operations. This paper will touch upon the integrated modelling and digital capabilities of the IDM through the lens of a couple of case studies – one in the design and one in the operate phase.
Revolutionising Cement Evaluation in Mexico's Exploration Wells: Unleashing the Power of Extreme Ultrasonic Technology
Authors: Moncayo S. , Juaristi J. M. , Vilchez O.
Published: February 2024

The evaluation of well cementing has historically been a point of great importance during well construction. The evaluation of cementing has evolved over the last decades into an increasingly demanding technique, driven by both stricter regulatory requirements and more complex well construction designs.

Over the years, regulatory and normative requirements have evolved to ensure safety and environmental protection up to the surface. Isolation must be demonstrated after well construction, as well as at the end of the well's life before it is plugged and abandoned.

Cement bond log (CBL) and variable density log (VDL) were introduced in the 1960's. These tools provide qualitative insights into the cement's bond with the formation (VDL). This is achieved through the propagation of acoustic energy, leveraging the variance in acoustic impedance between the pipe and the material behind it—whether it be solid, liquid, or gas.
Added Values From CFD on Equipment Troubleshooting Diagnosis
Authors: Maktar M. Fariz , Chauvet Christian J.
Published: February 2024

Computational Fluid Dynamics (CFD) is branch of fluid mechanics that uses numerical analysis to simulate and solve fluid flow within products or systems operating under real-world conditions. It is a powerful tool that has numerous benefits in the oil and gas industry. Very often, CFD simulations are performed at design phase to ensure that equipment designed will achieve the desired performance. Similarly, CFD simulations can also be used to analyse existing equipment to ensure that it can adapt to new operating constraints and objectives. This paper focuses on the added values brought by CFD in diagnosing issues faced by a heat exchanger due to a change in its operating condition. A heat exchanger was reported to have perforated tubes, and a lab report showed that it was due to naphthenic acid corrosion (NAC) attack. Plant operators tried to resolve this by injecting a corrosion inhibitor (CI); however, the tube perforation still occurred. A CFD study was performed to understand and investigate the reason why tube perforation persisted even after CI introduction. The inlet and outlet areas of the heat exchanger were checked, as these areas corresponded to the tube perforation locations. CFD results showed presence of dead zones within the heat exchanger. A direct correlation was established between perforated tube locations and the dead zone locations where high acid Heavy Vacuum Gas Oil ( HVGO) had accumulated over time. Infinite contact time between the high acid HVGO and tube walls at these dead zones had subsequently rendered the CI ineffective. This led to direct NAC attack on the tube walls. Based on these findings, a countermeasure has been proposed and validated through CFD. The results show that dead zones are no longer present within the heat exchanger. Positive feedback from plant operators has been received, as no similar issue had been raised after three years since implementation. In second case study, the flow behavior within fire water system was replicated by means of CFD. Results show presence of deep vacuum within the overboard piping line during the operation of Pressure Control Valve (PCV). This led to huge force spike and pipe surge at the top pipe segment. Installation of vacuum breaker was recommended. Without being able to visualize the internal flow in the heat exchanger via CFD, it might have been difficult to anticipate the root cause behind this tube perforation. "X-ray vision" provided by CFD, gave engineers a better understanding of what had occurred, hence enabling us to pinpoint the exact root cause of the issue. This approach of troubleshooting and diagnosing equipment via CFD had not only provided significant cost cuts by minimizing physical assessments but had also delivered prompt responses and quick solutions to plant operators, ensuring fast turnaround.
Re-Use of Offshore Facilities to Facilitate Marginal Field Development
Authors: Abidin Z. F. Zainol , Mustapha M. , Shaipulah A. M
Published: February 2024

In recent marginal field developments with challenging reservoir characteristics and economics, PETRONAS has embarked into a new concept of field development utilizing relocatable Wellhead Platform (WHP), Export Pipeline and Floating, Production, Storage & Offloading (FPSO) facilities. One of the notable unique technical aspects of this concept is the use of Suction Pile Foundation to anchor the fixed WHP on the seabed instead of the conventional pile method. Retreval of the foundation is possible without damaging the jacket, thus allowing relocation of the WHP to other potential field without major structure modification.

The first WHP that utilized this concept was the Ophir Development. In 2017 Ophir encountered early cessation of production. Hence, PETRONAS had the opportunity to explore re-locating the Ophir facilities to another marginal field development. This relocation has safeguarded PETRONAS’ financial exposure for early termination of FPSO leasing contract, and re-use of the WHP and flexible flowline.

The Development team was tasked to conduct an asset portfolio screening (based on selection criteria) to identify a suitable marginal field that could benefit from these assets. Working together with the execution team and technology vendor, several platform relocation methods were assessed. The recommendation for field relocation was made based on the most feasible and economically attractive option.

Integration and collaboration of multiple parties from the development, abandonment and execution teams were crucial in ensuring success of the project. Taking into account technical requirements and challenges that were anticipated in facilities relocation has enabled relocation of the WHP to be completed in less than 30 days with a 40% cost saving in comparison to conventional development plan.

This project has demonstrated PETRONAS’ agility to identify a feasible solution to turn setback into opportunity, further demonstrating proof of concept for the ‘hummingbird’ development to unlock multiple marginal fields and at the same time minimizing abandonment liability and exposure due to early cessation of field production.

This paper explains the processes that have taken place and the technical consideratiosn in implementing a hummingbird’ facilities relocation project for marginal field development.
Cheaper Structural Underwater Inspection with New Technology
Authors: Zuraimi F. , Bolhassan R.
Published: February 2024

Currently, the cost of inspecting structural joint weld below 30m is very expensive as it requires the use of a saturation diving. Conventionally, this is done through Magnetic Particle Inspection (MPI), and it is the only underwater inspection activity that requires the use of saturation diving.

In 2022, a pilot project was carried out by Shell Malaysia at F23 field in Sarawak waters to study the feasibility of an alternative method known as the Alternative Current Field Measurement (ACFM) method for underwater joint inspection. Whilst there have been numerous study that scrutinize the reliability and accuracy of such method, there aren't that many publications that addresses the feasibility of the technology in actual offshore environment.

Based on the pilot project, the ACFM method was 40% more cost effective, and it is safer than the conventional method as the operation can be done remotely with the ROV (Remotely Operated Vehicle). However, there were numerous constraints such as the difficulty to clean the marine growth with ROV, the reliability of the ACFM components and difficulty to access tight areas which will be detailed in this paper.
Efficiency Below the Surface: Enhance Production with Subsea Seawater Injection and Treatment
Authors: Yeaw S. , Haruna O. S.
Published: February 2024

The offshore industry has continuously evolved in the quest to unlock more subsea reserves with higher recovery rates. Among various innovations, the utilization of advanced subsea systems, such as subsea pumps and seawater treatment, has emerged as a cost-efficient method for enhancing recovery while requiring minimal modification to existing topside infrastructures, enabling greenfield developments and long tiebacks.

Subsea seawater treatment for water injection offers several inherent advantages over topside treatment. Notably, its modular approach and simplicity increase flexibility for reservoir engineers, enabling effective reservoir management by facilitating water injection at any desired capacity, location, and time. Moreover, the ability to provide customized water for injection into oil reservoirs represents a transformative opportunity for offshore oilfield production companies, enabling them to produce more, faster, and with reduced emissions.

This paper aims to share the key design aspects of a subsea seawater treatment and injection system, covering the key technology components, operational experience, system integration, and achievable water quality.
Semen parameters in testicular tumor patients before orchiectomy: What is the impact of testicular tumor stage and histology?
Authors: Mendes Gonçalo , Teixeira Bernardo , Madanelo Mariana , Rocha Alexandra , Mesquita Sofia , Vital João , Monteiro Miguel , Fraga Avelino , Louro Nuno
Published: February 2024

Purpose: To evaluate the influence of testicular cancer histology and stage on sperm parameters in cryopreserved samples collected prior to orchiectomy. Materials and methods: We conducted a retrospective analysis of tumor histology, stage and sperm parameters of patients who underwent pre-orchiectomy sperm cryopreservation for testicular cancer between March 2010 and March 2023. The World Health Organization (WHO) 2010 sperm reference values were used to identify patients with subnormal semen parameters and to further categorize patients by sperm alteration. Localized disease was classified as Stage I, while metastatic disease encompassed Stages II and III. Continuous variables were compared using t-test or Mann Whitney U test, and categorical variables using Chi-square and Fishers exact test. Results: A total of 64 patients was identified, 48 (75%) classified as stage I and 16 (25%) classified as stage II/III. No difference was found in semen parameters between patients with seminoma and patients with non-seminoma germ cell tumor (NSGCT). Patients with stage II/III disease had significantly lower percentages of progressive motility (36% vs 53%, p=0.021) and total motility (60% vs 69%, p=0.015) than stage I patients. When categorizing by sperm alterations according to WHO 2010 reference values, patients with stage II/III disease had significantly higher proportions of asthenozoospermia (38% vs 15%, p=0.048) and teratozoospermia (63% vs 31%, p=0.027) than stage I patients. Elevated tumor markers were not associated with sperm abnormalities. Conclusions: Patients with metastatic testicular cancer present with worse sperm quality than patients with localized disease. Sperm cryopreservation should be offered to all patients with testicular cancer, and especially emphasized in patients with metastatic disease.
Minimal invasive treatment of urethral strictures: An experimental study of the effect of paclitaxel coated balloons in the wall of strictured rabbit’s urethra
Authors: Pagonis Konstantinos , Peteinaris Angelis , Adamou Constantinos , Tatanis Vasileios , Vagionis Athanasios , Natsos Anastasios , Obaidat Mohammed , Faitatziadis Solon , Liatsikos Evangelos , Kallidonis Panagiotis
Published: February 2024

Purpose: The aim of this study is the evaluation of the distribution of paclitaxel (PTX) released by a coated balloon in the layers of rabbit’s urethra.Methods: 18 rabbits were included. A laser device was used for the stricture formation. After two weeks, dilation of the strictured urethra was performed by using Advance 35LP PTA balloons and Advance 18 PTX PTA balloons. The experimental models were divided into 3 groups. The group Α included two rabbits without any intervention except for the stenosis procedure. Group B compromised six rabbits that underwent dilation with Advance 35LP PTA balloons. Group C consisted of 10 rabbits to which dilation with both Advance 35LP PTA balloons and Advance 18 PTX PTA balloons was applied. Histological evaluation and Immunohistochemistry were performed on all specimens.Results: Inflammation, fibrosis and ruptures were detected in the specimens of the study. In specimens of Group C the decrease of inflammation and fibrosis rate was greater. Anti-PTX antibody was detected in the epithelium, lamina propria and smooth muscle layer of all specimens of urethras that have been harvested immediately and 1 day after the dilation with Advance 18 PTX PTA balloon and it was not observed in any layer of the urethral wall of the rest of the examined specimens of Group C.Conclusions: PTX’s enrichment was detected in the smooth muscle layer of all specimens that have been harvested immediately and 24h after the dilation with Advance 18 PTX PTA balloons. PTX may play an inhibitive role in the recurrence of the stenosis.
О сходимости подпоследовательности частичных сумм многомерного тригонометрического ряда Фурье по Прингсхейму
Authors: Konyagin Sergei Vladimirovich
Published: February 2024

Из знаменитой теоремы А.Н. Колмогорова (1925) вытекает, что частичные суммы ряда Фурье любой интегрируемой функции $f$ одной переменной сходятся к ней в $L^p$ для всех $p\in (0,1)$. Известно, что для функций многих переменных это неверно. В работе доказано, что тем не менее для любой функции многих переменных найдется подпоследовательность частичных сумм по Прингсхейму, сходящаяся к ней в $L^p$ для всех $p\in (0,1)$. В то же время в достаточно общем случае при взятии частичных сумм ряда Фурье функции многих переменных по расширяющейся системе множеств найдется функция, для которой абсолютные величины некоторой подпоследовательности частичных сумм сходятся к бесконечности почти всюду. Это верно, в частности, для системы расширений фиксированного ограниченного выпуклого тела и гиперболических крестов.
Теоремы о следах и продолжении для однородных пространств Соболева и Бесова на неограниченных равномерных областях в метрических пространствах с мерой
Authors: Gibara Ryan , Shanmugalingam Nageswari
Published: February 2024

Для фиксированного числа $p$, $1\le p<\infty $, рассматривается неограниченное локально компактное неполное метрическое пространство с мерой $(\Omega ,d,\mu )$, в котором мера $\mu $ удовлетворяет условию удвоения и выполнено $p$-неравенство Пуанкаре, а $\Omega $ является равномерной областью в своем пополнении $\overline \Omega $. Показано, что следы функций из пространства Дирихле-Соболева $D^{1,p}(\Omega )$ на границе $\partial \Omega $ реализуются как функции из однородного пространства Бесова $HB^\alpha _{p,p}(\partial \Omega )$ для подходящего $\alpha $; здесь $\partial \Omega $ снабжена неатомической борелевской регулярной мерой $\nu $. Показано также, что если $\nu $ удовлетворяет $\theta $-коразмерностному условию относительно $\mu $ для некоторого $0<\theta <p$, то существуют ограниченный линейный оператор следа $T:D^{1,p}(\Omega )\to HB^{1-\theta /p}(\partial \Omega )$ и ограниченный линейный оператор продолжения $E:H B^{1-\theta /p}(\partial \Omega )\to D^{1,p}(\Omega )$, который является правым обратным для $T$.
Review of Research on Asymmetric Twin-Scroll Turbocharging for
Heavy-Duty Diesel Engines
Authors: Jin Jianjiao , Wang Jie , Zhang Chenyun , Cao Tianyi
Published: February 2024

Asymmetric twin-scroll turbocharging technology, as one of the effective
technologies for balancing fuel economy and nitrogen oxide emissions, has been
widely studied in the past decade. In response to the ever-increasing demands
for improved fuel efficiency and reduced exhaust emissions, extensive research
efforts have been dedicated to investigating various aspects of this technology.
Researchers have conducted both experimental and simulation studies to delve
into the intricate flow mechanism of asymmetric twin-scroll turbines.
Furthermore, considerable attention has been given to exploring the optimal
matching between asymmetric twin-scroll turbines and engines, as well as
devising innovative flow control methods for these turbines. Additionally,
researchers have sought to comprehend the impact of exhaust pulse flow on the
performance of asymmetric twin-scroll turbines. Drawing on a comprehensive
review of prior research endeavors, this study presents a meticulous summary of
the advancements made in asymmetric twin-scroll turbocharging technology, with a
specific focus on its application in heavy-duty diesel engines. By analyzing and
synthesizing the findings from these previous investigations, this work also
identifies the existing challenges and outlines the future research priorities
in this field. The continued exploration and optimization of asymmetric
twin-scroll turbocharging technology holds immense promise in enhancing fuel
economy and mitigating nitrogen oxide emissions. Consequently, this research
contributes to the ongoing efforts aimed at achieving sustainable and
environmentally friendly transportation solutions.
Re-positioning university libraries for relevance in a dynamic learning environment
Authors: Onwusu-Ansah Samuel , Korkuvi Pearl Joan
Published: February 2024

During the COVID-19 pandemic, university libraries are characterised as highly responsive and receptive to technological innovation, and emergent teaching and learning paradigms in the educational landscape. The exploratory design was adopted to gain insight from library leaders/directors in Ghana. A purposive sampling method was used to sample library directors from four universities in Ghana. Our paper found that libraries in Ghana provide virtual services including libguides, e-resources, online chat systems, etc. to support the changing user needs in the information environment. However, major innovations instituted during the pandemic are discovery services, web 3.0-based, multimedia technology services and research data management. Our paper revealed that, major shifts in pedagogy and technology have occurred in education, demanding effective communication, collaboration, and teamwork by library staff in meeting universities' teaching, learning, and research mandate. Consequently, providing innovative library services and facilities aligned with university pedagogy must be strongly emphasised by the library leaders.
Dimensions of Accessibility and Use of Information Communication Technology Among Cocoa Farmers in Atwima Mponua District, Ghana
Authors: Tham-Agyekum Enoch Kwame , Awuku Beatrice Offeibea , Ankuyi Fred , Appiah Patrick , Osei Collins , Bakang John-Eudes Andivi De , Okorley Ernest Laryea
Published: February 2024

This research examined the drivers of accessibility and use of information communication technologies (ICTs) by cocoa farmers. A sample size of four hundred (400) cocoa farmers was selected using a multi-stage random sampling procedure. Data were analysed using percentage, means, standard deviation, Kendall’s coefficient of concordance and multiple linear regression model. The study revealed that mobile phones, radio and television are the most available (=4.99, 4.95 and 4.85 respectively), accessible (=4.97, 4.83 and 4.40 respectively) and utilised (=4.97, 4.81 and 4.30 respectively) ICT tools by cocoa farmers. There is a relatively high level of availability of ICT (=3.57), a moderate level of accessibility (=2.90) and low use (=2.19) of ICT tools. Cocoa farmers mainly used ICT tools to acquire information on their cocoa farm activities (=4.82). Gender, age, education and farmer-based organisation participation affected farmers' accessibility of ICT tools. Age, education and farm experience significantly affected farmers’ use of ICT tools. The greatest challenge faced by cocoa farmers in accessing and using ICT tools is a lack of skills in operating the tools ( rank=2.24). Training on ICT use should be intensified by all relevant stakeholders to enable cocoa farmers to increase their use of ICT tools.
Indigenous Preparation Methods of Medicinal Plants Used for the Treatment of Small Ruminant Diseases in Imo State, Nigeria
Authors: Ani Anthony Okorie , Onuoha Eugenia Nneka , Umunakwe Polycarp Chika , Nwakwasi Rachel Nkeonyere , Aja Ogbonna Okoro
Published: February 2024

The study examined the use of medicinal plants for the treatment of small ruminant diseases in Imo State, Nigeria. A multi-stage sampling procedure was used to select 120 small ruminant farmers for the study. A structured interview schedule was used to collect data. Data were analysed using mean and percentages. Retained placenta (82%), pneumonia (82%), foot rot (82%) and helminthosis (81%) were the common diseases of small ruminants in the area. Available medicinal plants were Garcinia kola (93%), Ageratum conyzoides (92%), Costus afer (91%) and Vernonia amygdalina (80%). Many medicinal plants were used in the treatment of more than one small ruminant disease. Roots (98%), leaves (98%), juice (93%) and stems (91%) were the highly used plant parts for the preparation of the remedies. Squeezing (98%), mixing with palm oil (97%) and pounding (91%) were the highly used preparation methods for herbal remedies by the farmers. The study concluded that medicinal plant species were used for the treatment of small ruminant diseases in the study area. Therefore, the government and other relevant stakeholders should promote the use of medicinal plants for the treatment of small ruminant diseases.