bluuebunny/crossref_metadata_2025 huggingface dataset:
Validation of FY-4A/AGRI LST and High Temporal-spatial Resolution Analysis of Surface Heat Resources in Hunan Province, Central China
Authors: Fan Jiazhi , Lin Hao , Han Qinzhe , Chen Leishi , Tan Shiqi , Li Wei
Published: September 2023

Land surface temperature (LST) is a crucial parameter in climate and ecology, exerting significant influence on meteorological conditions, ecosystems, and human life. LST data sources are diverse, with remote sensing being the prevailing means of acquisition. FY-4A/AGRI offers high-quality LST products for East Asia. In this study, we evaluated the performance of the product in Hunan Province and conducted refined analysis of surface heat resources based on the 4km/1h resolution product over a two-year period. The results demonstrate that the FY-4A LST product effectively captures surface temperature (R=0.893), albeit with a relatively high error level (Bias=-6.295℃; RMSE=8.58℃), particularly in capturing high LST values. The performance of this product is superior in the eastern flat terrain area of Hunan Province compared to its performance in the western mountainous region due to environmental conditions causing systematic errors that contribute to instability in detection deviation for this product. Surface heat resources are more abundant in eastern Hunan Province than in mountainous areas located west and southwardly, and the detailed distribution of them at finer scales is mainly influenced by the terrain and climate conditions. There is no obvious seasonal difference in the distribution of heat resources except in winter, and rapid urbanization within Chang-Zhu-Tan urban agglomeration during two years has significantly altered the spatial distribution pattern of surface heat resources across Hunan Province. These findings provide a quantitative baseline for assessing FY-4A satellite's detection capability while serving as a reference for further application of its LST products and establishing foundations for divisional classification and utilization strategies pertaining to surface heat resources within Hunan Province.
Interactions of Metal Ions with Fulvic Acids: Particle Size Distribution, Colloidal Stability and Thermodynamic Aspects
Authors: Klučáková Martina , Krouská Jitka , Kalina Michal
Published: September 2023

The interactions of metal ions with fulvic acids resulted in changes in the particle size and charge. Particle size distribution was trimodal for fulvic acids, bimodal for fulvic complexes with calcium and magnesium, and copper-fulvic complexes had only one size fraction. The compensation of negative charge of carboxylic and phenolic functional groups by positive charged metal ions resulted in the increase in zeta potential which was getting closer to zero in the case of copper-fulvic complexes. However, all metal humic complexes behaved as colloidally unstable which resulted in visually observable sedimentation. Calorimetric measurements provided positive values of changes in enthalpy which indicated endothermic processes. In contrast quantum chemical calculations as well as experiments with model compounds provided negative values indicated exothermic processes. Changes in Gibbs energy were determined as negative and changes in entropy as positive which meant spontaneous processes.
RBD-Adjuvanted Preparation: Evaluation of IgG and IgM Antibodies for One Year and Cross-Reactivity with Omicron Variant in Mice
Authors: Gimenes Lima Gabrielle , Da Costa Hernan Hermes Monteiro , Prudencio Carlos Roberto , Portilho Amanda Izeli , De Gaspari Elizabeth
Published: September 2023

This study continued the analysis of immunization with the receptor binding domain (RBD) associated with the adjuvants Dimethyldioctadecylammonium bromide (DDA) and Saponin (Sap) (RBD+DDA/Sap) or Aluminum hydroxide (AH) and outer membrane vesicles (OMVs) of Neisseria meningitidis (RBD+AH/OMV); from adult to old age and assessed maternal-fetal transference of antibodies. Outbred Swiss mice were immunized with 2 intramuscular (IM) doses with the antigenic preparations RBD+DDA/Sap, RBD+AH/OMV or RBD alone. The humoral immune response was evaluated using ELISA, avidity-ELISA, Immunoblotting and a Omicron-surrogate-neutralization assay (BA.1), while the cellular immune response was analyzed by ELISpot. Our previous work studied the IgG response; here, we verified that IgM levels were higher right after the immunization doses, but, as IgG, it persisted until 368 days after the immunization. The avidity of IgM increased from low to intermediate-to-high after the booster dose. RBD+DDA/Sap presented neutralizing indexes against Omicron at days 47 and 176, while RBD+AH/OMV showed neutralization on days 21, 47 and 176. Cellular response, measured 465 days after immunization, revealed IFN-Y and IL-4 secretion. The offspring of RBD+DDA/Sap had detectable antibodies, which decreased around 45 days after birth, the last point we analyzed. The results suggested that DDA/Sap is a promising adjuvant mixture to enhance humoral and cellular immune response against SARS-CoV-2, improving maternal-fetal transference of antibodies; cross-reactivity with Omicron variant; and the maintenance of antibodies for a long period.
Effect of Film Thickness on Microstructural and Magnetic Properties of Lithium Ferrite Films Prepared on SrTiO3 (001) Substrates
Authors: Liu Kun , Zhang Ruyi , Lu Lu , Li Jiankang , Zhang Songyou
Published: September 2023

Epitaxial lithium ferrite (LiFe5O8) films with different thicknesses have been successfully fabricated on SrTiO3 (001) substrates by magnetron sputtering deposition technique. The microstructural and magnetic properties are characterized by advanced transmission electron microscope and magnetic measurement device. It was found that the formation of structural defects can be influenced by the thickness of the film. Apart from the misfit dislocations, the orientation domains form in thinner film and twin boundaries appear in thicker film, respectively, contributing to the misfit strain relaxation in the heterosystem. The magnetic measurement shows that the thinner films have enhanced magnetization and a relatively lower coercive field compared with the thicker films containing the antiferromagnetic twin boundaries. Our results provide a way for tuning the microstructure and magnetic properties of lithium ferrite films by changing the film thickness.
Cholinergic Polarization of Human Macrophages
Authors: Roa-Vidal Natalia , Rodriguez-Aponte Adriana S , Lasalde-Dominicci José Antonio , Capó-Vélez Coral M , Delgado-Vélez Manuel
Published: September 2023

Macrophages serve as vital defenders, protecting the body by exhibiting remarkable cellular adaptability in response to invading pathogens and various stimuli. These cells express nicotinic acetylcholine receptors, with the α7-nAChR being extensively studied due to its involvement in activating the cholinergic anti-inflammatory pathway. Activation of this pathway plays a crucial role in suppressing macrophages' production of proinflammatory cytokines, thus mitigating excessive inflammation and maintaining host homeostasis. Macrophage polarization, which occurs in response to specific pathogens or insults, is a process that has received limited attention concerning the activation of the cholinergic anti-inflammatory pathway and the contributions of the α7-nAChR in this context. This review aims to present evidence highlighting how the cholinergic machinery in macrophages, led by the α7-nAChR, facilitates the polarization of macrophages towards anti-inflammatory phenotypes. Additionally, we explore the influence of viral infections on macrophage inflammatory phenotypes, taking into account cholinergic mechanisms. We also review the current understanding of macrophage polarization in response to these infections. Finally, we provide insights into the relatively unexplored partial duplication of the α7-nAChR, known as dup α7, which is emerging as a significant factor in macrophage polarization and inflammation scenarios.
Human Right to Access Public Information: The Experience of Ukraine and the Practice of the ECtHR
Authors: Shevchuk Oleksandr Mykhailovych , Drozdov Oleкsandr Mykhailovych , Kozak Vadim Anatoliyovych , Vyltsan Anastasiia Oleksandrivna , Verhoglyad-Gerasymenko Оlena Volodymyrivna
Published: September 2023

The guarantee of ensuring the right to access public information is an important condition and criterion for functioning in a legal democratic state. In addition, realizing the right to access public information is essential for preventing and detecting corruption. The purpose of this work is to analyze international legal rules and standards, as well as to provide some examples of the practice of the European Court of Human Rights in the context of the implementation of the right to access public information. It has been established that the right to access public information is a component of the human right to information and is a fundamental constitutional human right. The existing practice of the European Court of Human Rights confirms the importance of protecting the right of access to public information. It indicates to states that it is mandatory to comply with it, the expediency of applying an effective system of control measures to implement the right under study. The paper analyzes theoretical and legal approaches to understanding the human right to access public information and determines its place in human rights. An analysis of the practice of the European Court of Human Rights regarding the right to access public information made it possible to identify existing shortcomings in the legislation of the Member States and Ukraine and to find ways and methods for solving such problems and prospects for preventing such violations in the future, as well as the possibility of applying the decisions of the European Court of Human Rights to improve the current domestic legislation in this area.
Disgorgement of Profits: An Alternative Solution to Stolen State Assets’ Recovery from Corporate Financial Crimes
Authors: Ariyanny Renny , Bae Sung-jun , Dermawan Mohammad Kemal , Bosch Anna
Published: September 2023

In recent years, the Indonesian government has suffered a huge loss of state assets due to the misbehavior of corporations in financial management because the Indonesian legal system does not have a specific regulation to address corporate financial crime. When a corporate financial crime case arises, Indonesian law enforcement approaches this crime using the Anti-Corruption Act. However, the aim to retrieve the stolen government assets purloined by a corporation using the Anti-Corruption Act is still insufficient, therefore, other related regulations such as the Money Laundering Act have to apply as an additional instrument to realize optimal recovery from the misbehaving corporation. Because the long process involved in criminal and civil courts it is sometimes a waste of the law enforcement effort and the funds expended to get paid back from offenders and/or corporations because the money received is much lower than the money lost or even zero. To bridge the gap between the money lost initially and the repayment money, because of the lack of special legal regulation concerning corporate financial crime, this research intends to study the possibility of using a “disgorgement of profits” approach as a faster way to get the maximum repayment of stolen money/assets from instances of corporate financial crime in out-of-court settlements.
Genişletilmiş Analiz Yöntemine Dayalı Bulanık AHP ve TOPSIS Yöntemi ile Danışmanlık Sektöründe Sunulan Hizmetlerin Değerlendirilmesi
Authors: EKİN Emre , CESUR İlayda Gökçe
Published: September 2023

Amaç: Günümüzde hizmet çeşitliliğinin çok fazla olması ve rekabetin yoğunlaşması işletmelerin sunduğu hizmet kalitesinin artmasını zorunlu kılmaktadır. İşletmeler, çok farklı ve zor kriterler altında kararlar almak ve sürekli iyileştirmeyi esas alan bir yapı oluşturmak için yoğun çaba sarf etmektedirler. Bu çalışmada, hizmet sağlayıcıların işletmelerden bekledikleri faktörlerin değerlendirilmesi ile ilgili genel olarak belirsiz ve değişken faktörler BAHP ile modellenmiş ve karar verme sürecinde en etkili ve önemli kriterin belirlenmesi amaçlanmıştır.
Tasarım/Yöntem: Uzmanlar tarafından yapılan ikili karşılaştırmalara ilişkin yargılar sözlü olarak ifade edildiğinde bu sözel belirsizliği ortadan kaldırmak için Bulanık AHP yöntemi kullanılmıştır. BAHP yöntemleri arasında en sık kullanılan yöntem Chang'in Genişletilmiş Analiz yöntemidir. Çünkü yöntemin işlem adımları kolay, anlaşılır ve kısadır. Alternatif değerlendirme için TOPSIS yöntemi kullanılmılştır. Bu yöntemde alternatifler ideal duruma göre belirli kriterler altında maksimum ve minimum değerler arasında karşılaştırılmalıdır. TOPSIS, alternatiflerin en iyi çözüme (pozitif-ideal çözüm) göreli yakınlığını göz önünde bulundurarak karar vericilerin sıralarını belirlemelerinde çözüm sunar.
Bulgular: Bulanık AHP ile ulaşılan kriter ağırlıklarından yararlanarak işletmede verilen hizmetler TOPSIS ile listelenmiş, verilen en iyi hizmet belirlenmiştir. İşletmede sunulan 10 adet danışmanlık hizmeti ele alınmıştır. Bu puanlar ve bulanık AHP ile ulaşılan kriter ağırlıkları kullanılarak sunulan hizmetler listelenmiştir. Çalışmada 10 alternatif ve 5 kriter incelenmiştir. Danışmanlık firmasının sunduğu hizmetler değerlendirildiğinde Ar-Ge Danışmanlığı olarak belirlenmiştir.
Sınırlılıklar: Örneklemin sadece hizmet sektöründe faaliyet gösteren danışmanlık firmasında uygulanması araştırımanın sınırlılıklarıdır.
Özgünlük/Değer: Hizmet sektörü, ülkemizde pazar payı, işletme sayısı ve ticaret hacmi açısından büyük bir paya ve ağırlığa sahip olduğundan bu sektör dikkate alınmıştır. Tüm sektörlerde olduğu gibi hizmet sektörü de verdiği hizmetin kalitesini artırmayı, müşterilerine kaliteli bir hizmet sunarak hem müşteri portföyünü hem de kazancını artırmayı hedeflemektedir. Hizmet sektöründe sunulan hizmetlerin bulanık yöntemlerle değerlendirildiği çalışmalar oldukça sınırlıdır. Bu çalışma hizmet sektöründe faaliyet gösteren firmalara ışık tutacaktır.
Pearl Harbor Baskını’nın Maliyet Fayda Analizi Açısından Değerlendirilmesi
Authors: YUKCU Suleyman , ÖZBEK Ali
Published: September 2023

Öz Amaç: Bu çalışmanın amacı, geçmiş tarihte yaşanan ve dünya tarihinde önemli bir olay olarak görülen Pearl Harbor Baskını’nın yönetim muhasebesi kapsamında maliyet fayda analizi çerçevesinde incelenmesini ve değerlendirilmesini sağlamaktır. Tasarım/Yöntem: Çalışmada Pearl Harbor Baskını’nın Japonya ve Amerika Birleşik Devletleri açısından maliyet analizi tasarlanmıştır. Bulgular: Çalışma sonucunda; Pearl Harbor baskını’nın yönetim muhasebesi açısından maliyet-fayda analizi kapsamında değerlendirilmesi sağlanmış olup çeşitli çıkarımlar sağlanmıştır. Japonların Pasifik Okyanusu üzerinde hegemonyasını koruma ve prestijini kurtarma çabalarının kısa ve uzun vadede ne gibi etkiler ortaya çıkarabileceği, Amerika Birleşik Devletleri’nin bu saldırıya ne şekilde karşılık verdiği, savaşın sonuçlarının yönetim muhasebesi açısından maliyet fayda analizinin yapılması ve gelecekte bu tür olaylar karşısında karar alma mekanizmalarına çalışmanın yön vereceği düşünülmektedir. Sınırlılıklar: Çalışmada Pearl Harbor baskını’nın konu edinilmesi ve benzer olayların çalışma kapsamı içerisine dahil edilmemesi çalışmanın sınırlılıkları içerisindedir. Özgünlük/Değer: Çalışmanın başka alanlarda yoğun bir şekilde çalışılmasına karşın muhasebe alanında maliyet fayda analizi açısından irdelenmesi literatüre önemli bir kazanım sağlayabileceği açısından çalışmanın özgün değerini oluşturmaktadır. Anahtar Kelimeler: Pearl Harbor, Maliyet-Fayda Analizi, Yönetim Muhasebesi
Normal(leştirilen) Toplumlar, Anormal Güvensizlikler ve Patolojik Cinayetler
Authors: TAN Gülçin Özge
Published: September 2023

Amaç: Bu makalenin amacı, bir iktidar tekniği olarak normalleştirmenin kadın cinayetleri bağlamında ele alınması ve Foucaultcu güvenlik toplumu yaklaşımıyla kadın cinayetlerinin analiz edilmesidir.
Tasarım/Yöntem: Makalede nitel araştırma tekniği kullanılmıştır. Bu doğrultuda, kadın cinayetleri, Türkiye’deki belirli örnekler üzerinden literatürdeki çeşitli tartışmalarla ilişkisel olarak bir arada değerlendirilmiştir.
Bulgular: Bu makalenin ulaştığı sonuca göre, bir iktidar tekniği olarak normalin belirlenmesi, normal dışında kalanları riskle ilişkilendirerek onları harcanabilir bedenlere çevirir. Güvenlik iktidarını büyüten bu ataerkil paradigma, kadın bedenini bir yandan disipline ederken bir yandan da kadının özgürlüğünü, yaşam hakkı karşılığında gasp etmektedir. Ayrıca normalleştirme tekniğinin hukuku muğlaklaştırması da makalenin vardığı diğer önemli sonuçtur.
Sınırlılıklar: Tercih edilmiş bir sınırlılık olmakla birlikte kadın cinayetlerine belirli bir paradigma içinden bakmak makaleyi sınırlandırmaktadır.
Özgünlük/Değer: Kadın cinayetlerini ve cinayetlerin normalleştirilmesini bir iktidar tekniği olarak ele almak, makalenin özgün yanı olarak öne çıkmaktadır.
Comparison between Real-Time Ultrasound-guided Percutaneous Dilatational Tracheostomy and Surgical Tracheostomy in critically ill Patients: A Randomized Controlled Trial
Authors: Kim Shin Young , Lee Seung Won , Baek Aerin , Park Ki Nam
Published: September 2023

Objectives Tracheostomy is an important procedure for critically ill patients in the intensive care unit (ICU), and percutaneous dilatational tracheostomy (PDT) has gained popularity due to its safety and effectiveness. However, there are limited data comparing ultrasound-guided PDT (US-PDT) with surgical tracheostomy (ST). In our previous study, we reported that US-PDT had similar safety and effectiveness to ST, with a shorter procedure time. However, the study design was retrospective, and the sample size was small. Therefore, we conducted a randomized controlled trial to demonstrate the safety and efficacy of US-PDT compared to ST.Methods A total of 70 patients who underwent either US-PDT (n=35) or ST (n=35) were enrolled in the study between October 20, 2020 and July 26, 2022. The patients were randomly assigned to their respective procedures. The data collected included patient clinical characteristics, procedure time and details, complications, duration of ICU stay, time taken for weaning from mechanical ventilation, and hospital mortality.Results The procedure time of US-PDT was shorter than that of ST (4.0±2.2 minutes vs. 10.1±4.6 minutes). The incision length of US-PDT was also shorter than that of ST (1.5±0.5 cm vs. 1.8±0.4 cm). There were no statistically significant differences in demographics, procedure details, complications, length of ICU stay, ventilator weaning time, and hospital mortality.Conclusion US-PDT has a similar complication rate and shorter procedure time compared with ST. It can be safely and effectively performed in critically ill patients and can serve as a potential alternative to ST.
Exploring the Enhancement of Rigless Deployed ESP Technology for Ad-Interim Production
Authors: Al-Shunaiber Fahad , Al-Dossari Ibrahim , Windiarto Yhossie
Published: September 2023

The electrical submersible pump (ESP) change-out using the workover rig contributes to significantly deferred production, including waiting for rig availability, wellsite preparation, and rig mobilization. Finding an alternative ESP deployment method to minimize the deferred production associated with ESP failure is always prioritized during peak global oil demand. This paper focuses on the lessons learned from a temporary slim cable deployed ESP field trial installed for the Ad interim production application.

A temporary thru-tubing ESP deployment concept was adopted to allow producing the well until mobilizing the workover rig to replace the failed permanent ESP. The slim cable deployed ESP system uses an inverted high-speed ESP architecture, and the permanent magnet motor offers a broader ESPs operating range and operational flexibility. The compact design simplifies the ESP installation using a standard slickline operation and well-control procedure.

The slim cable deployed ESP system was successfully installed thru 4-1/2-inch tubing above the failed ESP. The system's performance was observed during the field trial period, including fully rigless deployment capability in a live well, ESP operational flexibility, and well control guidelines.
Enhancing Production from High-Enthalpy Geothermal Wells with New Electric Submersible Pump Technology
Authors: Radov M. , Hamitoglu Y. , Sentürk E. , Tüzen M. K. , Holzmueller J. L. , Goertzen W. K. , Nyayadhish V. , Kulkarni O. S. , Amutha Nilavazhagan V. , Wu J. , Tan P. , Rao A. R. , Usta A. T.
Published: September 2023

This paper presents advancements in electrical submersible pump (ESP) technology that were specifically designed for use in high-enthalpy geothermal wells. It discusses the unique challenges associated with geothermal operations and highlights the opportunities offered by the new ESP technology to enhance production from these wells. The paper also provides a comprehensive overview of the key components of the ESP system, including the motor, protector, pump, power cable, motor lead extension, and downhole sensors. The new ESP system demonstrates improved reliability, power density, and operational efficiency by using high-efficiency permanent magnet motors, innovative encapsulation technologies, and optimized pump designs. The paper also highlights the successful field trial of the newly developed geothermal ESP in Kizildere Field that showcased its enhanced reliability and increased production in a high-temperature environment. The findings from this trial have paved the way for the design and implementation of the new ESP system in additional high-enthalpy wells, further expanding the application of ESP technology to geothermal energy extraction. Overall, this paper underscores the transformative potential of ESP technology in enhancing the use of geothermal resources for sustainable energy production.
Ultra-High-Speed High-Gas-Volume-Fraction Pump Development
Authors: Ejim C. E. , Xiao J. , Shakirov A. , Alexeev Y. , Shkolnyi A.
Published: September 2023

Wellbore conditions below bubble point pressure in high gas-oil-ratio (GOR) wells result in very high amount of free gas at the inlet of Electric Submersible Pumps (ESP). Conventional multiphase pumps have limitations handling free gas exceeding 75% intake gas-volume-fraction (GVF). The objective of this work is to develop and field test a new Ultra-High-Speed High-Gas-Volume-Fraction (UHS HGVF) pump system. The ultimate goal is to facilitate sustained production from wells experiencing high-GVF production challenges.

The UHS HGVF pump is a new type of submersible pump with an architecture being investigated to boost hydrocarbon production from high GOR oil wells. The principle of operation is based on turbulent friction, in which a spatial vortex flow is formed, rotating together with the rotor and moving along its axis. The pump housing diameter is 4.00 inches and operates at a shaft rotational speed in excess of 3.5 times those of conventional pump systems. Hydraulic design, computational fluid dynamics analysis, prototyping and physical testing were performed to optimize the performance of the UHS HGVF pump.

The results show that the new pump architecture is capable of handling gas-liquid mixtures with intake GVF well beyond the 75% GVF limitation of conventional multiphase pumps. This was mainly attributed to the pump features, which impart the required amount of energy and turbulence to the gas-liquid mixture but simultaneously minimizes separation of the gas and liquid phases. These combined effects facilitated thorough mixing of the gas-liquid streams ensuring the pump provided sufficient pressure boost for the downhole setting depths which the system was designed. The system was also observed to have a high capability of sand tolerance and thrust handling. The ruggedized system has the required attributes to withstand operation in gassy field conditions.

This work presents a conceptually new approach to pump development with the aim of overcoming hydrocarbon production challenges in wells with very high free gas at pump intake. The UHS HGVF pump widens the operating envelope to produce a high GOR well, thereby achieving production gains in gassy conditions, where conventional systems are limited. The system therefore serves as an essential artificial lift tool to handle production in increasing numbers of extremely gassy wells.
Improving ESP Survivability in the SAGD Environment: An Integrated Approach to Managing ESP Performance in Challenging Conditions
Authors: Joseph Rejish , Babatunde TK , Briceno Lisett , Gaviria Fernando , Plaxton Bill
Published: September 2023

Firebag SAGD (Steam Assisted Gravity Drainage) asset has shown steady growth in well count, with ESPs (Electric Submersible pumps) as the primary mode of lift. In the high temperature environment, robust design and material selections are important considerations to achieve long run lives. However, key constraints such as economic conditions, increasing well count and changing well performance require solutions that optimize cost and reliability. This is critical to offering flexibility in approaches to addressing the top failure modes of the ESPs at Firebag. The paper discusses Suncor's efforts to prioritize not only prevention, but also management of the key failure modes to optimize reliability and cost in the SAGD environment by developing a better understanding of the problem. This includes novel approaches to treat an installed ESP as a repairable system through cable-only replacement (non-serviced motor reruns) and re-landing an ESP as-is when a cable failure is located close to the surface. Risk mitigation is done primarily through data analysis of teardown information and statistical survivability rates at both the system and sub-component level. This risk mitigation includes building the foundation for information gathering through a clear teardown process on every ESP pulled from service, gaining insights on failures, challenging traditional assumptions based on the data obtained, and driving focused trials and initiatives.
Case Study: Predicting Electrical Submersible Pump Failures Using Artificial Intelligence and Physics-Based Hybrid Models
Authors: Silvia Shejuti , Furlong Ted
Published: September 2023

Unplanned electric submersible pump (ESP) failures cause significant revenue loss due to deferred production, and increased operational cost associated with emergency workovers. Timely prediction of failures due to critical operating conditions can help operators take proactive actions to avoid sudden ESP failures. Traditional condition-based monitoring (CBM) methods generate overwhelming alarms based on deviation from fixed thresholds. Due to the dynamic behavior of the reservoir, these alarm thresholds need to be fine-tuned frequently to generate useful insights. Moreover, these alarms often yield a short lead time to a critical event or failure, leaving little room for taking preventive actions.

A major operator in Latin America was experiencing similar operational challenges. In this case study, we show how ESP Predictive Failure Analytics (PFA) helped this operator to identify critical events while the ESPs were running and to take proactive actions to extend ESP run life.

Methods, Procedures, Process

PFA uses artificial intelligence (AI), physics-based and expert knowledge-based methods to predict short-term damage events, such as a broken shaft, short-circuit, grounded downhole failure, as well as long-term damage events, such as pump low efficiency, sand, scale, deposition, or gassy conditions that can lead to failure. PFA combines these damage events probabilities with parametric survival analysis to predict ESP Remaining Useful Life (RUL).

Results, Observations, Conclusions

PFA In this study, we demonstrate PFA results for two ESPs. PFA raised a broken shaft/ missed pump stages alarm for ESP run# 4 in well 1 after a sudden motor current and production rate decline. Due to this signal, PFA estimated a significant reduction in RUL. After observing these results, the operator increased the motor speed to improve production. PFA then raised another alarm for downthrust condition, reducing the RUL further. PFA enabled the operator to quickly schedule a workover, reducing downtime. For ESP run# 7 in well 2, PFA estimated a steady decline in RUL due to motor temperature and vibration increase over time. The operator avoided the imminent failure by reducing the pump speed, which helped decrease the motor temperature and increase the ESP run life.

Methods, Procedures, Process

PFA is a unique approach that combines AI, physics-based, and expert knowledge-based approaches to provide interpretable predictions of ESP failure. Unlike traditional CBM approaches, PFA generates fewer alarms with longer lead times, enabling the operator to take preventive measures to avoid sudden failure. In addition, PFA ranks ESPs based on criticality, which enables effective surveillance of large number of wells.
Assessment of Real-Time ESP Failure Prediction Using Digital Twin, Machine Learning and Damage Modelling
Authors: Melo R. A. Lastra , Worth D. J. , Swaffield S.
Published: September 2023

In the presented research, an assessment was conducted of how machine learning techniques, in combination with physics-based damage modelling, could be capitalized on to help move towards the goal of developing an effective and automated real-time ESP failure prediction system. A prediction model was developed that has the capability of predicting two groups of failure mechanisms. One group consisted of failures related to pump wear and scale plugging and the other group consisted of failures related to increased drag (rotational resistance) in either the motor or the pump. The model was designed to both predict the remaining useful life (RUL) of the ESP and provide an alarm when the ESP is expected to fail within the next 90 days (PF_90). The base form used for the model was a Long Short-Term Memory (LSTM) neural network. Interesting aspects of the model include: specifically designed training targets allowing for both an RUL estimate to be provided over the life of an ESP and the simultaneous prediction of both RUL and PF_90; specifically designed inputs calculated from the raw data as based on the physics-based damage modelling; and a unique architecture for the LSTM network, allowing for multiple failure mechanisms to be better represented. The performance of the prediction model was promising: an average score of 73% (on a test dataset) was achieved using the chosen performance metric for the research, the F1_Score.
Field Validation: ESP Reliability Monitoring and Production Optimization by Trending Condition and Performance Data Extracted from ESP Surface Electrical Signals
Authors: Badkoubeh A. , Waldner L. B. , Imanfard M.
Published: September 2023

This paper presents the results of an ongoing extended field trial on multiple ESP systems in a SAGD field in Canada. The main objective of this field trial is to evaluate the impact of the condition monitoring technology introduced in this paper to address a gap in predictive and preventative maintenance programs for ESP applications. Specifically, the results are used to determine the ability to monitor and quantify the impact of (a) power quality, (b) adverse flow regime and (c) undesirable mechanical vibrations on ESP production and reliability using data extracted from electrical lines supplying the power to ESPs. The data collected from several wells on a single production pad were trended over several months to determine warning thresholds and subsequently operational recommendations to improve overall production and reliability performance. The information collected from this field trial is intended to demonstrate the effectiveness and benefits of this condition monitoring approach in the Operators field.

The described condition monitoring technology is based on measurements of high frequency electrical signals, 3-phase current and voltage, from the VFD panel supplying power to the ESP. Previous SPE papers, SPE-201169-MS and SPE-204522-MS, covered the core concept and enabling components of this technology. These papers shows examples on mechanical, electrical and flow regime diagnosis and demonstrated a direct correlation between the periodic mechanical vibration in an ESP and the frequency component in the electrical current signals. This foundational work was largely the basis of the extended field trial discussed in this paper. The results, presented in this paper, demonstrate interesting findings in how this method of condition monitoring can provide meaningful insights into the operation and reliability of the operating ESP systems.
Study on Flow Characteristics of a Rotating Centrifugal Impeller Under Gassy Flow Based on Dynamic Mode Decomposition (DMD)
Authors: Zhu Jianjun , Wang Haoyu , Li Nan , Cao Guangqiao , Zhang Yongxue , Li Yuanyuan , Zhu Haiwen
Published: September 2023

Electric submersible pumps (ESPs) are widely used in both onshore and offshore oil fields. However, the impeller of an ESP has strong fluctuation and obvious disturbance structure under the condition of gas-liquid two-phase flow, which leads to significant performance degradation. Dynamic mode decomposition (DMD) method is a data-driven approach that can effectively identify the characteristic frequency of unsteady flow and capture the disturbance structure in the flow field. In this paper, DMD method is used to decompose and reconstruct the phase and velocity fields in the impeller of an ESP. The main modal structure and frequency information are obtained. The future flow field is predicted to verify the feasibility of DMD method within high-speed rotating flow fields. The results show that DMD method can effectively extract the main flow structure of the flow field in space and time, which can also be used to check the flow stability. Applying DMD method to the analysis of unsteady flow field is important for flow feature extraction, flow phenomenon analysis and flow mechanism interpretation.
Lesson Learned from Digital Oil Field Implementation in ESP UCR Wells
Authors: Gamboa J. , Grohman L. , Colter M. , Zejli A.
Published: September 2023

This paper summarizes lessons learned from a 2-year program aiming at the implementation of Digital Oil Field (DOF) across unconventional resources (UCR) fields produced with ESP. First, the outcomes of the 6-month pilot program are presented. The goal of this pilot was to define workflows and practices for (a) data collection and processing, (b) automatic ESP model matching and VLP generation, and (c) well optimization. Next, digital oil field (DOF) implementation is discussed including data integration, well test validation and learnings from field optimization with gas lift and ESP wells. Petroleum Expert DOF is software application chosen for this project, therefore, most of the discussion is focused on Petex suite: Prosper, GAP and DOF.

The introduction of unforeseen biases through data treatment is one of those learning. For example, a downtime event would introduce zeros in the averaging of operating frequency potentially causing unrealistic low frequency values while pressure build-up during downtime would drive an over-estimation of average intake pressure. Likewise, we learnt the importance of qualitative match between model results and ESP real-time data analysis. Most engineers would gain confidence in simulation results if the model outcome matched real-time ESP trend interpretations. Finally, a brief discussion of ESP model-based optimization is carried out in the context of UCR wells.

Despite successful deployment across multiple Permian fields and automatically matching more than 100 ESP wells every month, the team learnt that tool true value is only achievable through broad user adoption. Therefore, training and mentoring are discussed as well as the creation of tools that speed up model building bottlenecks.
Case Study: Customized Solution Used to Successfully Set ESPs in Unconventional Wells with Complex Mechanical Geometries Where Other Artificial Lift Methods are Unsuitable
Authors: Martinez Villarreal Paola Elizabeth , Morales Diego Armando Marquez , Briceno Argenis Alberto Garces
Published: September 2023

One of the technical considerations for selecting the appropriate artificial lift system for a well is a suitable well construction; this includes the deviation, dogleg severity (DLS), direction, and wellbore size. The different artificial lift types can be affected by the well construction in different ways; some systems cannot pass through a highly deviated section, and others cannot operate in a high-DLS section. The maximum deviation that equipment can pass through without risk of permanent damage depends on factors such as equipment outer diameter, casing inner diameter, equipment length, metallurgy, and different equipment series combinations.

This case study presents the successful installation of nine flanged electrical submersible pumps (ESPs) in unconventional wells operated by an independent oil and gas company in the Permian's Delaware Basin, which is one of the most-prolific unconventional oil and gas basins in the US. The results of this study demonstrate how customized strings using high-grade materials, enhanced pump types, and more-efficient motors can operate in wells with complex mechanical geometries in which standard-flanged ESPs and other artificial lift systems are considered unsuitable.
The Value of Pump Discharge Pressure Measurements and their Application for Improving Performance and Operation of ESPs
Authors: Narvaez D. , Aylett D. , Botros K.
Published: September 2023

While most of the offshore and high-profile land electric submersible pump (ESP) installations are equipped with downhole sensors for measurement of operating conditions at the pump intake and discharge, ESP systems in land operations typically do not include pump discharge pressure sensors. For these systems, we rely on measurements of intake conditions—wellbore pressure and temperature, motor oil and/or motor winding temperature, and vibrations—and operating parameters measured at surface.

The limited use of discharge sensors is often due to a reduced clearance between the motor outside diameter and casing inside diameter. There are applications where physical limitations are not a concern, yet some operators choose to run only the base unit for monitoring intake measurements because they do not see a benefit on adding discharge pressure data.

The objective of this paper is to demonstrate the value of adding discharge pressure data to the monitoring system when used in conjunction with the other real-time downhole and surface measurements to evaluate and optimize performance of ESP systems.

Case examples of field operations will be presented to illustrate how pump discharge pressure measurements contributed to an effective and timely diagnostic of critical operating conditions and optimization of ESP performance operating in challenging conditions such as: multiphase flow, slugging flow and gas interference, flow restrictions, solids buildup, and changes in inflow performance or fluid properties.

Pump discharge pressure monitoring has been available for decades but as of today, the value and use of this powerful resource is overlooked in many land operations that could benefit from it to implement a comprehensive program of real-time surveillance, remote control, and optimization of ESP systems.
ESP System Monitoring and Diagnosis from Surface Power Acquisition
Authors: Hoefel A. , Kelly D. , Jin R. , Meier D. , Chu T. , Anderson J. , Chong J.
Published: September 2023

Electrical submersible pump (ESP) operation is very sensitive and is challenging to monitor and diagnose because of limited downhole sensor information. A new data acquisition (DAQ) system for ESP system diagnosis overcomes this limitation by also including abundant information in the electrical surface signals. The diagnosis covers the surface equipment, cable, and downhole equipment based on a comprehensive combination of all available measurements, actuator (adjustable control inputs, such as voltage, frequency and surface choke position) settings, and calculated electrical performance parameters[from power quality monitoring (PQM)].Through spectral analysis electrical signal analysis (ESA) evaluates even theelectrical signal higher frequency contents to get even more insight into the downhole equipment. The analysis outcome supports maintenance and optimization with a comprehensive assessment of system and component health. Additional capabilities enable assessment and optimization of operational conditions.
Permanent Magnet Motor Safety – The Big Short Question
Authors: Collins Charles , Cookson Austin , Cloud Brandon , Harris Dennis
Published: September 2023

With the emergence of permanent magnet motors (PMM) in the ESP industry, new challenges have arisen regarding the potential for electrical energy generation during installation, operation, and pulling of the equipment. Among these challenges include how to properly terminate the ESP power cable conductors at the cable ends or point of work. Safety being of the highest importance, robust methods for terminating the conductors during each of these processes are necessary to prevent field electrical incidents.

Numerous opinions have been expressed and methods developed across the industry on how best to perform cable terminations, many of which are not compatible with each other. The industry's lack of agreement on when to apply each method and understanding on best practices has significant potential for serious field personnel safety incidents. This underscores the need for establishing the most robust methods considering the wide variety of potential scenarios that could be encountered.

This paper will evaluate six cable termination approaches through physical motor testing. A PMM with conductors connected to a long ESP cable reel will be forced to rotate at various speeds. The motor terminals and cable termination will be instrumented to measure both phase-to-phase and phase-to-ground voltage as well as current. Each approach will consider both ideal conditions and suboptimal conditions that may occur from downhole insulation damage. More than 100 permutations of these possible situations will be compared and evaluated. Recommendations will be made based on these results on when each termination method might be a valid and safe option including rankings to show which methods safely cover the broadest set of situations.

The results of this method comparison will provide actionable data such that the safest cable termination methods can be chosen. This will also guide field personnel on which methods should be avoided. Ultimately, this will contribute to establishing best practice throughout the ESP industry for conductor handling when PMM ESP systems are involved.
A Step-By-Step Holistic Methodology Quantifies and Reduces Harmonics on ESPs, Increasing Revenue by USD 500,000 Per Year: A Case Study from a field in Ecuador
Authors: Carrillo Kevin Ismael Andagoya , Leon Jorge Luis Villalobos , Orozco Andrés , Batallas Estefi , Toledo Luis , Enriquez Luis , Reyes Carlos
Published: September 2023

Harmonics are widely known occurrences that negatively affect electrical equipment. Therefore, it is crucial to conduct detailed studies to quantify and understand their effects in order to effectively manage them. This study aims to characterize harmonics specifically on the load side of variable speed drives (VSDs), with the objective of capturing both current and voltage downhole motor waveforms and analyzing their impact on electrical submersible pump (ESP) applications installed at ~9,500 ft vertical depth designed for oil producing. The VSDs evaluated are located in different production clusters within a Field located in Ecuador. In this field 98% of the wells use ESP as artificial lift method with several types and models of variable speed drives (VSDs) to run the downhole equipment. The wide range of equipment available in the field offers an optimal population for performance comparison and data collection. Additionally, the study data is complemented by dismantle, inspection, and failure analysis (DIFA) reports of retrieved equipment, which enhanced the understanding of the effects of harmonics.
The Impact of Response Biases on the Variation in Life Satisfaction
Authors: Klement Johannes
Published: September 2023

Despite the abundance of empirical research on life satisfaction, disparities remain regard- ing its variation. Using data from the German Socio-Economic Panel (SOEP), this study analyses to what extent biases in the design and implementation of life satisfaction sur- veys influenced the variation in life satisfaction. The study employs various methodologi- cal approaches, including distributional analysis, descriptive statistics, Markov transition probabilities and logistic regression. Consequently, this study demonstrates the significant positive and non-adaptive changes in life satisfaction that can arise when an interviewer is present during a survey. Moreover, the method of measuring life satisfaction on an eleven- point integer scale has a substantial impact. The midpoints of the scale are frequently used by individuals to assess their lives, which results in a balance between positive and negative evaluations. These findings have broader implications for the overall level of variation. It appears unlikely that an average life satisfaction score of more than 8 can be maintained over the long term on a scale of 0 to 10. It should be noted that the scale also impacts adaptive processes. Additionally, the patterns of dissatisfaction and satisfaction variation differ. For a more nuanced understanding of the causes, future research may benefit from analyzing periods of satisfaction and dissatisfaction with life separately.