bluuebunny/crossref_metadata_2025_split huggingface dataset:
New Integrated Approach to ESP Management - Successful Strategy to Optimize Well Production and ESP Run Life
Authors: Spagnolo Salvatore , Pignotti Eleonora , Scarso Marco , Cappuccio Pasquale , Pilone Salvatore , Valente Alberto , Gonzalez Zamora Mariangela , Ciavarro Lucio 
Published: August 2022

Abstract
Our analysis identified specific best practices to help Production Engineers improve the performance of the ESP system. We demonstrated how, by closely monitoring the interactions between injected chemicals and pump control parameters, the ESP run life can be increased and total cost of ownership reduced. ESP are used in depleted reservoirs, but failure rate poses economical limitations when rig availability is low and workover costs are high. To minimize the deferred production, we devised a comprehensive strategy for de-risking ESP operations with ad-hoc chemical treatment. Many variables are analyzed in literature to increase ESP run life. However, they are often treated standalone. We evaluated previous studies conducted in this field, both at downhole level and surface production facilities. We focused our quantitative analysis on the interaction between reservoir fluids and ESP system to identify detectable signatures on pump control parameters. We continuously monitored operation of pumps at field level through real time data and identified distinctive anomalies in specific wells. We ran software simulations to evaluate likelihood and type of scale deposition downhole. We selected ad-hoc chemical treatment and accurately measured impact on ESP control parameters. Initially we observed a decrease in delta pressure (pump intake vs. pump discharge) in a well, a trend that was determined by possible pump plugging. The team decided to collect field samples of the produced fluids. A chemical downhole model was calculated through software simulation, then an ad-hoc chemical treatment was selected for the specific application. The team then iterated the solution in the field using additives for: i) inhibiting formation of further deposits; ii) removing existing scale deposits at ESP level. With rigorous evaluation of the new pump conditions through remote live monitoring and continuous adjustment of chemical treatment, the well showed a positive gain of delta pressure indicating the effectiveness of the solution. In the following months, well tests were conducted on site with test separators to collect actual data on the additives used. This allowed the team to fine-tune the long-term treatment program after further reducing the chemical dosage to optimize OPEX. Our study identified specific variables that Production Engineers must analyze when operating ESP in high-risk/high-return projects. Also, we identify a general methodology to promptly intervene in case of erratic pump behavior. The paper describes for the first time what a comprehensive production solution can do in increasing ESP run life while restoring production in complex wells prone to scale deposition. Software analysis and continuous data collection/interpretation from downhole pumps were key aspects to mitigate risk
A Data-Driven Approach to Predict the Critical Gas Flow Rate in Gas Wells
Authors: Rahmati Ehsan , Sim William Michael Nathan , Moffett Ross Edward , Pond Christopher Burke , Hingerl Ferdinand Franziskus 
Published: August 2022

Abstract
Liquid loading is a major factor limiting the production of gas wells. Liquid loading starts when the gas production rate does not provide sufficient transport energy to lift the liquid out of the well. The downhole liquid accumulation imposes an additional hydrostatic backpressure on the formation and decreases the production capacity of the well. This paper presents a data-driven model to predict the minimum gas rate required to lift the liquids out of the well.
A dataset consisting of 394 horizontal plunger-lift gas wells was used to train the data-driven model. A total of 32,292 points of liquid loading onset were found in the dataset and the corresponding gas flow rate was labelled as the target. Principal Component Analysis and Mutual Information Regression were performed to choose twelve most influential features on the critical gas flow rate (target). A model group consisting of three different machine learning algorithms and ten different data preprocessing steps was trained on the dataset. The most accurate model in the group was chosen to be the critical gas flow rate model.
Results showed that the data-driven critical gas flow rate model predicts the critical flow rate with R2 scores of 0.97 and 0.90 for train and test datasets, respectively. Also, the model results were compared to a few well-known empirical correlations in the literature (Turner, Coleman, Belfroid, Wang, Nagoo, and Shekhar equations). Results confirmed that the data-driven model has the highest agreement with the Belfroid model in comparison with the other equations. Next, an unsupervised learning method was used to modify the Belfroid equation. The modified correlation was proposed as a simple engineering tool to calculate the critical flow rate with higher accuracy in comparison with other correlations studied. It was observed that the Belfroid model underestimates the critical flow rate by around 32% and 5.2% for wells with tubing pressures lower than 300 Psig and higher than 300 Psig, respectively.
Most of the current critical flow rate models are based on two theories to explain the onset of liquid loading, droplet reversal and film reversal. Yet, the liquid loading mechanism is unknown due to the complexity of dynamic interactions between the reservoir and wellbore. Besides, most of the current models have their own limiting assumptions. This study provides a model that avoids unlikely theories or unrealistic assumptions and utilizes one of the biggest datasets of wells.
Automated ESP-Lifted Well Startup Using Model Predictive Control: Introduction of the Algorithm and Field Tests Results
Authors: Sadowska Anna , Steenson Leo , Williams Michael , Meredith Andrew , Chong Jonathan , Anderson Jeffery , Kelly Dwayne 
Published: August 2022

Abstract
The start of an electric submersible pump (ESP) is the most dynamic event in the life of the ESP, and one that has been shown to be the main contributor to the premature failure of the ESP; yet it is clearly unavoidable. This article introduces an algorithm comprising of a model-predictive controller and a moving horizon estimator for automating the well startup. Objectives and constraints related to the startup are considered for the whole well system, including the reservoir, the ESP, the tubing etc. A lumped-parameter model is established to model the fluid dynamics in the system.
The estimator recalibrates the model and provides estimates (virtual measurements) in lieu of unavailable physical measurements. The operating sequences for the ESP and choke are then updated step-by-step by the controller, considering the model of the system, the startup objectives and constraints, and the measured feedback information from the wellbore gauges.
The startup algorithm was implemented on a field edge device and deployed to a well in the Permian Basin. The algorithm executed two successful startups. A model recalibration was conducted before the second startup which improved the accuracy of setpoint tracking.
Prediction of Viscosity Correction Factors for ESP in Viscous Applications
Authors: Sheth Ketankumar Kantilal , de Long Robert Charles 
Published: August 2022

Abstract
Electric submersible pumps (ESPs) are currently being tested in the service company's newly built viscous lab testing loop; whereby, the viscous performance of each pump stage type is analyzed at multiple speeds and viscosities.
This viscous lab testing loop is capable of speeds up to 70 Hz, 30,000 B/D of fluid, with a maximum of 500 HP, and can manage fluid viscosities up to 2,500 cP. Four pumps were tested at speeds ranging from 40 to 70 Hz, in 10 Hz intervals, and up to 2,500 cP fluid viscosity. The viscosity correction factors, for each operating speed and viscosity, were developed for each pump stage and compared with the stage-specific speed.
The effects of viscosity and operating speed on flow, head, and horsepower were observed. An increase in viscosity deteriorates pump performance, while an increase in rotational speed reduces the rate of deterioration; therefore, increased operating speeds improve the performance of an ESP pump in viscous applications.
Additionally, diameter and specific speed effects (a "dimensionless[DL1] " number for pump design criteria) on viscosity are being investigated as a design criterion. A correlation is being developed for the effects of the specific speed on the viscosity correction factors. The new correlation will help obtain viscosity correction factors for other pumps with different diameters, operating at different speeds and viscosities, based on the specific speed relationship.
The service company's Research and Development department's viscosity testing program, its results, analysis, and new findings are discussed in this paper.
A Note on Negation of a Probability Distribution
Authors: Kaur Manpreet , SRIVAST AMIT 
Published: August 2022

Abstract
Evaluating the negation of an uncertain event is an open issue. Yager[14] suggested a transformation for evaluating the negation of a probability distribution. He used the idea that any event whose outcome is not certain can be negated by supporting the occurence of other events with no bias or prejudice for any particular outcome. Various authors have tried to generalize the negation transformation proposed by Yager[14] . However we need to focus on developing the basic structure of negation so that the behaviour of the process modelled by negation transformation can be understood in detail. Yager's negation is based on distribution of maximum entropy. If a probability distribution is uncertain(a state other than maximum entropy), the more iterations of negation, the more uncertain this probability event becomes eventually converging to a homogeneous state\textit{ i.e.} maximum entropy. In other words, it is the realization of the process. What is noted that during each negation, Yager's method ensures that the negation is intuitive, the next negation weakens the probability of the event occuring in the previous step. Since negation involves reallocation of probabilities at each step in such a way that the reallocation at each step can be determined from the reallocation at the previous step, therefore it is clear that Yager's negation has various attributes similar to that of a markov chain. In the present work, we have shown that Yager's definition of negation can be modelled as a markov chain which is irreducible, aperiodic with no absorbing states. Two examples has been discussed to strengthen and support the analytical results. Also we have defined an information generating function(IGF) whose derivative evaluated at specific points gives the moments of the self information of negation of a probability distribution. The properties of the generating function along with its relationship with the information generating function proposed by S. Golomb[2] has been explored. A closer look at the properties of IGF confirms the existence of markovian structure of Yager's Negation.Mathematics Subject Classification (2010) 90C70 · 90B06 · 90B50 · 90C05
Deformation mechanism and numerical analysis of seasonal landslide induced by permafrost degradation: a case study, Northeast China
Authors: Shan Wei , Ma Min , Guo Ying 
Published: August 2022

Abstract
There are few types of research on the occurrence mechanism and deformation characteristics of landslides induced by permafrost degradation. With the aggravation of climate warming, landslides are more and more common in permafrost regions. A slow landslide (the K178 + 530 landslide) in the permafrost region of the Xiao Xing'an Mountains in Northeast China was monitored for a long time. The deformation characteristics and occurrence mechanism of the landslide were studied using field investigation, on-site drilling, sensor monitoring, laboratory test, Google satellite image, unmanned aerial vehicle (UAV) photogrammetry, high-density electrical method, and ground-penetrating radar. In addition, a hydro-thermal-mechanical coupling model of frozen soil under saturated conditions was established to simulate the deformation process, pore water pressure change, and effective stress distribution of the slope, and the simulation results were verified according to the monitored data. The results show that the meltwater recharge caused by permafrost degradation reduced the cohesion and internal friction angle of the soil near the trailing edge of the landslide, thus providing dynamic and mechanical conditions for slope deformation. The melting of the continuous segregation ice in the active layer contributed to the formation of a sliding surface and provided deformation conditions for the start of the landslide. The combination of these two factors finally led to the occurrence of the landslide. According to its deformation mechanism, it can be judged that the landslide is a thrust-type landslide. In addition, the melting of ice lenses in the seasonally frozen layer is the main source of soil strength damage, and the landslide sliding rate reached the maximum when the ice lens melted completely. The K178 + 530 landslide is a typical case of landslides caused by permafrost degradation. This study provides a reference for the identification, early warning, and prevention measures of this type of landslide.
Mobility and HIV vulnerabilities among female sex workers in Guinea-Bissau: findings from an integrated bio-behavioral survey
Authors: Gorin Emma May , Lyons Carrie E , Jarrett Brooke A. , Djalo Mamadu Aliu , Barreto Kátia , Drame Fatou Maria , Baral Stefan 
Published: August 2022

Abstract
Background: Mobility is an important risk determinant for HIV given the potential for intermittent access to HIV services. Mobility may be particularly relevant among female sex workers, (FSW) who have been shown to be at high risk for HIV in settings around the world. Data regarding the role mobility plays in exacerbating HIV risks among FSW across Sub-Saharan Africa remains limited, and data on FSW in Guinea-Bissau is sparse.Methods: FSW in four regions of Guinea-Bissau were recruited with a respondent-driven sampling (RDS) method and participated in an integrated bio-behavioral survey. Associations between reported mobility and social and HIV vulnerabilities among FSW in Guinea-Bissau were assessed using multivariable logistic regression models. Results: 34.8% of respondents reported mobility to one location and 15.7% reported mobility to more than one location within the past six months. Statistical analysis demonstrated that mobility to more than one destination was significantly associated with recent sex without a condom with both clients (aOR: 2.57 (95% CI: 1.10, 6.00)) and non-paying partners (aOR: 4.73 (95% CI: 2.24, 10.02)) compared to non-mobility. However, mobility to one or more locations was also associated with higher odds of receiving HIV prevention information (mobility to one location: aOR: 1.63 (95% CI: 1.07, 2.49); mobility to >1 location: aOR: 2.34 (95% CI: 1.28,4.26)) and mobility to more than one location was associated with more engagement with HIV-related organizations (aOR: 2.26 (95% CI: 1.27, 4.04)).Conclusions: These results suggest that while some prevention services including HIV prevention information reach mobile FSW in Guinea-Bissau, HIV prevention needs remain unmet for mobile FSW in Guinea-Bissau.
Meat Quality of Sasso T44 and Koekoek cockerels exposed to temperature variation with supplementary Coriander seed powder
Authors: Gebreyohans Kiros Welay , Amaha Negassi , Demeke Solomon , Dubusho Legesse K. , Girma Mseret 
Published: August 2022

Abstract
This experiment was conducted to evaluate the effects of ambient temperature and coriander seed supplementations on meat quality of Sasso T44 and Koekoek. Both breeds were exposed to two temperatures rooms with a heated room of 32±1.2 0c from 11:00 am to 16:00 pm and the normal room temperature of average maximum and minimum of 23.8±30c and 16.6±1.60c, respectively, with a relative humidity between 34.5 ±4 to 44.8±3%. Both breeds were also further randomly allocated to three levels of 0g/kg, 5g/kg and 10g/kg coriander seed powder supplementations. The experiment was conducted from 10 to 20 weeks of age. There was a slight variation in meat color on lightness (L*; P<0.05) due to temperature at 48 hours after slaughtered. Breast meat from cockerels reared in a heated room became slightly lighter compared to groups reared at normal temperature (unheated room). However, the overall meat color did not categorized under the paled color of meat, rather it can be in the darker than normal category. Moreover, breast meat of Koekoek at 1hour after slaughtered was more yellow (P<0.05) in color and higher chroma values, while at 48 hours, Sasso T44 had redder meat (P<0.05) than Koekoek. In addition the thigh meat of Koekoek had more total ash than Sasso T44 (P<0.05). However, Sasso T44 breast meat had better water holding capacity due to lower in drip loss percentage (P<0.05) than Koekoek. This research indicated that some meat quality variations shown between breeds and due to temperature. However, further insights into other physical meat qualities and sensory evaluations may also reveal to the meat quality of these breeds.
Satellite assessment of eutrophication hot spots and algal blooms in small and medium-sized productive reservoirs in Uruguay's main drinking water basin
Authors: Zabaleta Bernardo Vicente , Aubriot Luis , Olano Hernán , Achkar Marcel 
Published: August 2022

Abstract

Intensive agricultural activities favor eutrophication and harmful phytoplankton blooms due to the high export of nutrients and damming of rivers. Productive watersheds used for water purification can have multiple reservoirs with phytoplankton blooms, which constitutes a high health risk. In general, water quality monitoring does not cover small and medium-sized reservoirs (0.25–100 ha) of productive use due to their large number and location in private properties. In this work, thein-situtrophic state of fourteen reservoirs was simultaneously assessed using Sentinel-2 images in the Santa Lucía River Basin, the main drinking water basin in Uruguay. These reservoirs are hypereutrophic (0.18–5.22 mg total P L-1) with high phytoplankton biomasses (2.8–4439 µg chlorophyll-a L-1), mainly cyanobacteria. Based on data generatedin-situand Sentinel-2 imagery, models were fitted to estimate satellite Chl-a and transparency in all the basin reservoirs (n = 486). The best fits were obtained with the green-to-red band ratio (560 and 665 nm, R2 = 0.84) to estimate chlorophyll-a and reflectance at 833 nm (R2 = 0.73) to determine transparency. The spatial distribution of the trophic state was explored by spatial autocorrelation and hotspot analysis, and the variation in spatial patterns could be determined prior and subsequent to a maximum cyanobacteria value in water treatment plant intakes. Therefore reservoirs with greater potential for phytoplankton biomass export were identified. This work provides the first fitted tool for satellite monitoring of numerous reservoirs, and strengthens the country's ability to respond to harmful phytoplankton blooms in its main drinking water basin.
Geomorphological analysis of landslide and early warning system for landslide risk mitigation in Nepalese mid-hills.
Authors: Thapa Prakash Singh , Adhikari Basanta Raj , Shaw Rajib , Bhattarai Diwakar , Yanai Seiji 
Published: August 2022

Abstract
The Nepalese Himalayas is one of the world’s most active mountain belts, with widespread natural hazards of various types, including landslides, which claim numerous lives and properties in Nepal. Landslides occur due to the combined effects of seismic activity, monsoon rainfall, and improper land-use practices. The prevention and mitigation of landslides are challenging for countries like Nepal, however, low-cost techniques such as bioengineering with low-cost early warning systems have been implemented in recent decades. The Methum landslide near Lalitpur was selected as a case study to investigate the landscape dynamics along with triggering factors, and to evaluate the effectiveness of a landslide early warning system (LEWS). The study assessed aerial photos, satellite images, and precipitation records and conducted multiple field visits to analyze patterns of landslide evolution, landslide risk, and potential triggers. Heavy rainfall, sloped terrace farming, and earthquakes are identified as major landslide triggers. LEWS, installed, measures rainfall, soil moisture, and displacement activity and generates an alarm if any of these parameters exceed the threshold set. This monitoring system is a cost-effective technique and exemplifies the reduction of landslide risk at the community level in the landslide-prone mid-hills of Nepal.
Study on the variation of MeHg content in different types of soils in non-ferrous metallurgical areas
Authors: Li Xinyu , Zheng Dongmei , Wang Yuqi , Xu Xiaoxiao 
Published: August 2022

Abstract
To study the methylation of mercury in soils of various utilization categories in typical non-ferrous metallurgical areas, soils of various utilization categories were selected for the experiment, and the changes of soil mercury, methylmercury, and SRB content were analyzed, whether the changes of SRB and the changes of soil physical and chemical properties affected the formation of methylmercury, and the results showed that: with the incubation time increased, the mercury content showed a decreasing-increasing-reducing trend. Except for the riverbank substrate, the MeHg content of the other five different land-use types exhibited a trend of rising and then falling, and the MeHg content of soils under flooded conditions was higher than that of non-flooded soils. SRB was present in all types of soils and promoted soil Hg methylation in the late incubation period. Among soil physical and chemical properties, pH and soluble sulfide were significantly correlated with MeHg content in some soils, indicating that MeHg formation was related to SRB, pH, and soluble sulfide, which is important for the study of different types of soils in non-ferrous metallurgical areas.