bluuebunny/crossref_metadata_2025 huggingface dataset:
A Comparative Effect of Clove Essential Oil with Multi-strain Probiotic and Antibiotic on Blood Biochemical Profile in Broiler
Authors: Shil Baishali , Gohain Anurup Kr. , Sonowal Mridushmita , Nath Rita , Acharjee Sapath , Borah Pranjal
Published: September 2021

Background: An experiment was conducted to compare the blood biochemical profile of broiler chicken feeding three different types of feed additives. Methods: 180 day old broilers chicks of Ven Cobb 400 strain were distributed randomly into 4 groups (T0, T1, T2 and T3) having 45 chicks in each group on the basis of their body weight. Each group divided into 3 replicates of 15 chicks in each. Rations are computed as per BIS (2007) to meet the nutrient requirement and other three groups (T1, T2 and T3) were offered the same standard ration of the control group but supplemented with zinc bacitracin @ 55 mg/kg (T1), probiotic @ 150 mg/kg (T2) and clove oil @ 400 ppm (T3). Result: The result of the experiment showed significant difference (p less than 0.05) in the level of Glucose in T3 group whereas, protein, albumin, globulin, A:G ratio, ALT and AST did not differ significantly (p greater than 0.05). Probiotic @ 150 mg/kg and clove oil @ 400 ppm supplemented groups showed significant (p less than 0.05) better cholesterol level compared to control and zinc bacitracin @ 55 mg/kg.
​Bibliometric Analysis of the Research Characteristics and Trends in Legume Mycorrhiza Field
Authors: Xu S.X.
Published: September 2021

Background: Legumes are notable for wide distribution and indispensable food function. Majority of legume species are known to form mycorrhizal symbioses. The visualized and quantitative analysis legume mycorrhiza research has been reported although much attention has been paid in this field. Methods: This study reviewed and analyzed systematically the research characteristics and trends in legume mycorrhiza by bibliometric method based on the citation data collected from the Web of Science Core Collection by CiteSpace software. Result: The publication concerning legume mycorrhiza research increases rapidly and is still a hotspot. The most active collaboration countries are USA, France, Germany, China and Australia, whereas the two institutions of University of Western Australia and Chinese Academy of Sciences collaborate most with others. The intellectual structure analysis showed that the main intellectual base is nitrogen-fixing of cereal. The top ranked of keyword by bursts was rhizobia with strength value of 5.2899, which began from 2016 and ended in 2018. The distinction of 24 bursting keywords is relatively small, which showed that the research hotpot and trend should be interaction between legume plants and mycorrhizal fungi for improving nutrition absorption, N-fixation, resistance to stress and their mechanisms in future.
Analysis of the market structure of long-distance transport vehicles in the context of retrofitting diesel engines with modern dual-fuel systems.
Authors: Chojnowski Janusz , Karczewski Mirosław
Published: September 2021

The demands placed on vehicles are constantly increasing. European legislation has forced commercial vehicle manufacturers to develop ever more powerful and dynamic engines with low fuel consumption. With the appearance of exhaust gas standards, truck manufacturers realized that it was necessary to improve the fuel supply system so that the combustion process was more efficient. To achieve this the fuel injected into the cylinders had to be finer in order to mix more easily with air. High-pressure unit injection systems have proved to be a good and reliable solution. They are also relatively cheap to produce and less prone to fuel contamination. Many years and millions of failure-free kilometers traveled on unit injectors effectively distracted some users and producers from the Common Rail system. Exhaust gas standards and increasing consumer expectations forced manufacturers to take another step in their development, i.e. the need for more precise fuel injection control. The injectors had to run faster in order to carry out the initiation dose, the actual injection and the extra injection. All these modifications make diesel engines in commercial vehicles such as tractor units much more powerful. They also allow for cooperation with aftermarket dual-fuel CNG-ON and LPG-ON installations. Dual-fuel solutions are perhaps another step towards reducing emissions, and thanks to reduced tolls, they are becoming a real alternative to conventional fuel-powered tractor units. This work focuses on the structure of the truck tractor market in terms of selecting cars used for the use of a non-factory dual-fuel CNG-ON installation.
Research of ecological indicators of two-way vehicle in stationary conditions
Authors: Kamińska Michalina , Andrzejewski Maciej , Daszkiewicz Paweł
Published: September 2021

The article concerns the research on the emission of pollutants of a rail-road tractor in two stationary research tests. The purpose of the tests was to carry out control tests of pollutant emissions and their analysis. The object used during the works was approved in accordance with the Stage V standard, which requires measurements of emissivity both in stationary, dynamic and real conditions. Despite the requirement to test engines installed on a vehicle during their normal duty cycle with PEMS, the emission limits measured in this test have not yet been defined. Therefore, the work below focuses on the stationary test cycle. The measurements were carried out in accordance with the combustion engine operating points described in the approval test, and then compared with the modernized NRSC test. It contains modified measuring points and rotational speeds of the crankshaft, adopted on the basis of the most common operating parameters of agricultural tractor combustion engines in real operating conditions. The measurements were performed with the use of a mobile dynamometer and devices for measuring emissions of harmful exhaust gas compounds and recording on-board data. In the test, the vehicle drive system worked at fixed operating points, with defined values of crankshaft rotational speed and load. Based on the recorded data on the concentrations of pollutants in the exhaust gases, the specific emission of the object was determined. In the final stage of the work, these data were used to perform a comparative analysis with the emission limits contained in the standard.
Arte monetária romana: reflexos de uma propaganda
Authors:   Universidade Estadual de Campinas, Carlan Cláudio Umpierre
Published: September 2021

A propaganda em Roma estava intimamente ligada às cunhagens monetárias. As moedas não apenas são instrumentos importantes para estabelecer a datação dos documentos que chegaram até nós sem seu contexto original, como são de grande valia na compreensão dessas mensagens simbólicas descritas no corpo da moeda. Com freqüência, o tipo monetário de reverso (conhecido por nós como coroa) mostra determinada estátua, representando uma divindade (Virtude, Júpiter, Hércules, a própria cidade de Roma, a VRBS...), uma construção (campo militar, portões de uma fortaleza), o exército (dois legionários montando guarda), cenas de batalha (imperador derrotando seus inimigos), casamentos, uniões dinásticas, tentativa de legitimar um determinado poder. Podendo vir acompanhado de legendas que podem identificar, ou não, a imagem.
O culto mariano e os vitrais da catedral de Chartres: a arte medieval: seu papel na religiosidade e suas relações com o espaço sagrado
Authors:   Universidade de São Paulo, Amorim Junior Elias Feitosa de
Published: September 2021

Este artigo tem o objetivo de apresentar algumas considerações iniciais referentes a minha pesquisa em andamento, na área de História Medieval, para o mestrado em História Social na Universidade de São Paulo.
Entre o clássico e o sublime: sobre a obra de William Turner e sua relação com as teorias da paisagem do final do século XVIII e início do século XIX
Authors:   Universidade Estadual de Campinas, Bertarelli Luciana Taniguti
Published: September 2021

O projeto de pesquisa em andamento tem como foco a obra do pintor de paisagem inglês William Turner produzida entre os anos de sua eleição como membro da Royal Academy, em 1799, e sua primeira viagem à Itália, em 1819.
Pedro Américo, Victor Meirelles entre: o passado e o presente
Authors:   Universidade Estadual de Campinas, Coli Jorge
Published: September 2021

As questões vinculadas aos estudos das artes brasileiras e, dentro delas, mais especificamente, às do século XIX, surgem num tecido histórico internacional, do qual, em primeiro lugar, é preciso ter consciência.
Arquitetura forense do estado de São Paulo: produção entre as décadas de 50 e 90 do século XX, sob a influência da arquitetura moderna
Authors:   Universidade de São Paulo, Cordio Maria Tereza Regina Leme de Barros
Published: September 2021

O trabalho proposto para a dissertação de mestrado que tenho desenvolvido dentro da Universidade de São Paulo, Escola de Engenharia de São Carlos, Departamento de Arquitetura e Urbanismo sob orientação do Prof. Dr. Miguel Antônio Buzzar, trata de um assunto aparentemente específico: a tipologia “Fórum de Justiça”.
Relevansi Ajaran Tasawuf Bagi Kehidupan Muslim di Era Modern
Authors:   Sekolah Tinggi Agama Islam (STAI), Madiun, Waskito Puthut
Published: September 2021

This research is based on the fact that materialistic culture is in rise and spread across Muslim society. Almost all aspects of life are judged only by material measures. On that basis, the author sees the relevance of Sufi teachings. This research is conduct through library research methode. The primary data sources in this study are Sufi literature and the social condition of Muslim community. The secondary data sources were obtained from several writings from Sufis observer and the results of Sufi practitioners in alleviating various problems and providing various solutions to the society. The results of this study indicate that the morals of Sufism as exemplified by the Prophet Muhammad are very relevant if applied to the current modern era. In addition, various ahwal conditions or spiritual conditions such as qurbah, khauf and raja' can contribute to peace of mind and human peace in everyday life in today's modern era. Especially it can reduce the condition of the soul which always refers to the aspect of materialism which is only focused on outward needs.
An Australian Pelican Pelecanus conspicillatus attacking a Rainbow Lorikeet Trichoglossus moluccanus being fed by people
Authors: Mo Matthew
Published: September 2021

Pelicans are generally piscivores, but occasionally prey on smaller waterbirds and other animals. I observed an Australian Pelican Pelecanus conspicillatus capture a Rainbow Lorikeet Trichoglossus moluccanus after both species had been attracted to people scattering seed for birds. The Pelican briefly caught the Lorikeet by the tail, but the Lorikeet escaped and flew away. To my knowledge, this is the first report of any pelican species capturing a parrot. It is unclear whether the Pelican was attempting to eat the Lorikeet.
Air Corridors: Concept, Design, Simulation, and Rules of Engagement
Authors: Muna Sabrina Islam , Mukherjee Srijita , Namuduri Kamesh , Compere Marc , Akbas M. Ilhan , Molnár Péter , Subramanian Ravi
Published: September 2021

Air corridors are an integral part of the advanced air mobility infrastructure. They are the virtual highways in the sky for transportation of people and cargo in the controlled airspace at an altitude of around 1000 ft. to 2000 ft. above the ground level. This paper presents fundamental insights into the design of air corridors with high operational efficiency as well as zero collisions. It begins with the definitions of air cube, skylane or track, intersection, vertiport, gate, and air corridor. Then, a multi-layered air corridor model is proposed. Traffic at intersections is analyzed in detail with examples of vehicles turning in different directions. The concept of capacity of an air corridor is introduced along with the nature of distribution of locations of vehicles in the air corridor and collision probability inside the corridor are discussed. Finally, the results of simulations of traffic flows are presented.
Task-fMRI Group and Functional Connectivity Analysis of the Brain During Faradarmani Consciousness Field Connection
Authors: Taheri Mohammad Ali , Torabi Sara , Nabavi Noushin , Modarresi-Asem Fatemeh , Abbasi Sisara Majid , Rezaei Ali , Maftoun Parisa , Semsarha Farid
Published: September 2021

Task fMRI has played a critical role in recognizing the specific functions of the different regions of human brain during various cognitive activities. This study aimed to investigate group analysis and functional connectivity in the Faradarmangars brain during the Faradarmani CF (FCF) connection. Using task functional MRI (task-fMRI), we attempted the identification of different activated and deactivated brain regions during the Consciousness Filed connection. Clusters that showed significant differences in peak intensity between task and rest group were selected as seeds for seed-voxel analysis. Connectivity of group differences in functional connectivity analysis was determined following each activation and deactivation network. In this study, we report the fMRI-based representation of the FCF connection at the human brain level. The group analysis of FCF connection task revealed activation of frontal lobe (BA6/BA10/BA11). Moreover, seed based functional connectivity analysis showed decreased connectivity within activated clusters and posterior Cingulate Gyrus (BA31). Moreover, we observed an increased connectivity within deactivated clusters and frontal lobe (BA11/BA47) during the FCF connection. Activation clusters as well as the increased and decreased connectivity between different regions of the brain during the FCF connection, firstly, validates the significant effect of the FCF and secondly, indicates a distinctive pattern of connection with this non-material and non-energetic field, in the brain.
Kepailitan Perseroan Perorangan dalam Undang-Undang Cipta Kerja
Authors: Gloria Monica
Published: September 2021

The times in the economic sector in fact encourage a country to try to provide regulations in accordance with global demands. One of them is done by Indonesia by using the Omnibus Law system, then regulating a new legal entity, namely an Individual Company. The application of this legal entity aims to encourage Micro and Small Businesses to be more developed, so that by turning them into legal entities, business owners will find it easier to get investment from banks and manage the company more regularly. However, in the event that the individual company bankruptcy application has not been regulated in the Cipta Kerja act or its implementing regulations, the purpose of this study is to see how the bankruptcy process of an Individual Company in Indonesia, using the normative juridical method, which looks at statue approach and conseptual approach.
Overview : International Guidelines on Natural and Nature-Based Features for Flood Risk Management
Authors: Bridges Todd , King Jeffrey , Simm Jonathan , Beck Michael , Collins Georganna , Lodder Quirjin , Mohan Ram
Published: September 2021

The application of natural and nature‑based features (NNBF) has grown steadily over the past 20 years, supported by calls for innovation in flood risk management (FRM) and nature‑based solutions from many different perspectives and organizations. Technical advancements in support of NNBF are increasingly the subject of peer‑reviewed and other technical literature. A variety of guidance has been published by numerous organizations to inform program‑level action and technical practice for specific types of nature‑based solutions. This effort to develop international guidelines on the use of NNBF was motivated by the need for a comprehensive guide that draws directly on the growing body of knowledge and experience from around the world to inform the process of conceptualizing, planning, designing, engineering, constructing, and operating NNBF.
UAE's First End to End Standardized Workflow-Based Digital Transformation in a Giant Gas Producing Asset - Lessons Learned and Way Forward
Authors: Alsaeedi Ayesha Ahmed Abdulla Salem , Elabrashy Manar Maher Mohamed , Alzeyoudi Mohamed Ali , Albadi Mohamed Mubarak , Soni Sandeep , Isambertt Jose , Tripathi Deepak
Published: September 2021

The concept of integrated modeling and digital transformation has grown within the oil and gas industry over the past decade and every such digital transformation has its own set of challenges from which significant learnings can be derived to enhance the knowledge base of the industry. This paper encompasses the successful achievement journey from the UAE's first end to end standardized workflow- based digital transformation in a giant gas producing asset, where several key challenges and learnings have been summarized that are originated from a unique project for a giant gas-condensate asset.

The role and importance from multiple business stakeholders such as the planning, engineering, operations and performance teams was imperative to establish a collaborative working philosophy and a detailed specification document, the end-to-end solution, functional and non-functional requirements were captured and aligned with end-user needs.

Firstly, a detailed offline phase along with focused efforts in understanding data-quality and establishing representative base-models, was key to enhance the benefit-realization of the integrated platform. Secondly, the online implementation helped in achieving significant process efficiency improvement as inbuilt data validation features significantly improved the confidence of the output.

The diagnostic workflows replaced the conventional spreadsheet-based approach. The digital platform works as a common reference of "truth" for everyone across the organization. It helped to produce several the business KPIs to assist the engineers in emphasizing on the problem area, such as improved well test planning.
Numerical Study on the Temperature Behavior in Naturally Fractured Geothermal Reservoirs and Analysis Methodology for Geothermal Reservoir Characterization and Development
Authors: Wei Cao , Cheng Shiqing , Jiang Bin , Gao Ruilian , Wang Yang , Song Jiayi , Yu Haiyang
Published: September 2021

An important way to develop geothermal energy is by producing low-medium temperature fluids from naturally fractured geothermal reservoirs. Pressure analysis is the most used to characterize such reservoirs for improving development efficiency. However, pressure inversion easily leads to non-uniqueness and cannot estimate thermal properties. Additionally, no reliable methods are proposed to evaluate the development potential of geothermal reservoirs. To narrow the gap, this study aims at studying the temperature behaviors and exploring suitable analysis method for characterizing geothermal reservoir and evaluating development potential.

The numerical and analytical models are simultaneously established to analyze the temperature behaviors. Our models account for the J-T effect (μJT), adiabatic heat expansion/compression effect (η), reservoir damage, viscous dissipation, heat conduction and convection effects. The solution's development is dependent on the fact that the effects of reservoir temperature changes on transient pressure can be ignored so that the pressure and energy equations can be decoupled. We firstly compute reservoir pressure field based on Kazemi model, then use this obtained pressure field to solve the energy-balance equations. The numerical solution is verified and is found to be in good agreement with the proposed analytical solutions.

This work shows that the most used constant μJT and η assumption will produce inaccurate temperature results when reservoir temperature changes significantly. Moreover, we find that temperature behaviors can exhibit three heat radial flow regimes (HRFR) and a heat inter-porosity regime with V-shape characteristic. Fracture thermal storativity ratio and matrix heat inter-porosity coefficient defined in this study can be estimated from this characteristic, which are further used to evaluate geothermal development potential. Our work also shows that temperature data can give information that would not be provided by conventional pressure analysis. The temperature derivative curve will show ‘hump’ characteristic if reservoir is damaged. The temperature data can characterize the skin-zone radius and permeability. More than that, the properties such as J-T coefficient, effective adiabatic heat expansion coefficient and porosity can be estimated. Eventually, an integrated workflow of using both temperature and pressure data analysis is presented to characterize naturally fractured geothermal reservoir for the first time. Simulated test examples were interpreted to demonstrate its applicability.
Application of Interventionless Single Point Entry Technology to Improve Proppant Placement Control and Well Production
Authors: Griffin J. , Rojas D. J. , Al Shmakhy A. , Scranton P.
Published: September 2021

The hydraulic fracture treatment (HFT) and its effectiveness to enhance wellbore drainage directly correlate with each well’s overall production performance and underlining economics. This paper will discuss the potential of ultra high stage count Single Point Entry (SPE) sleeves and their ability to increase control over proppant placement and isolation during the HFT as a method for optimizing well performance, economics, and reduce non-uniformity between treatments and wells.

To address the limitations of current completion methods, full ID single point entry systems have been developed for open hole and cemented applications. These systems provide unlimited frac stage count with lower frac tortuosity, provide increased control over proppant placement and well production, reduce or eliminate over- flush and formation damage, and achieve higher efficiency during and after frac stimulation than previous conventional plug-and-perf (PnP) and sleeve systems, thereby reducing costs.

While the ball-and-seat completion technique revolutionized the efficiency of multi-stage single point entry fracturing, its vast array of limitations (primarily ID restrictions), limited stage count, and compatibility with cemented liners quickly sidelined it in place of PnP. PnP offers increased surface area contact through additional entry points compared to sleeve systems of the past and remains the accepted method for achieving zonal isolation and initiation during stimulation. However, the time intensive operations of PnP present challenges in maintaining efficiencies due to variability in wireline during deployment and coiled tubing during millouts. The increase in number of clusters per stage and number of stages per well achieved with PnP often results in higher stimulated rock volumes (SRV) however, due to the number of multiple clusters open simultaneously, this method gained a "pump-n-pray" reputation due to the uncertainty of cluster efficiency and its unpredictability. The lack of cluster control over the years has created a series of challenges in terms of parent-child well relationships and spacing, economical asset development, and loss of potential production.

With over 4,000 stages fracture stimulated across US, Canada, and Asia, some wells containing 220 individual stages, this paper will address the differences in production in terms of bbl of oil equivalent (BOE) for direct and indirect offsets in trials, compare capital efficiency with spud to put on production (POP) timelines, demonstrate economical completion optimization for lower commodity pricing of oil, and carbon intensity reduction measures to lower greenhouse gas emissions.
Uncertainty Quantification of Allen-Cahn Phase Field Parameters in Multiphysics Simulation of Oil Shale Radio Frequency Heating
Authors: Ramsay Travis
Published: September 2021

Radio frequency (RF) heating represents a dielectric heating technique for converting kerogen-rich oil shale into liquid oil through in-situ pyrolysis. This process can be modeled using a multiphysics finite element based coupled thermal, phase field, mechanical and electromagnetic (TPME) numerical framework. This work focuses on the combination of a two-dimensional (2D) TPME multiphysics simulation with uncertainty quantification (UQ) that incorporates the Allen-Cahn phase field parameters, specifically those which describe the associated reaction-diffusion process as electromagnetic energy being converted to thermal energy in the RF heating process. The breadth of UQ performed in this study includes not only the Allen-Cahn parameters but also selected thermal, statistical rock-type distribution in the geological model, as well as electromagnetic parameters of the applied quasi-static Maxwell equation. A Non-Intrusive Polynomial Chaos (NIPC) is used for: considering the affect of Allen-Cahn phase field parameters on the evaluation of plausible conversion timelines of TPME simulation and the evaluation of summary statistics to predict the order of Polynomial Chaos Expansion (PCE) that is representative of full kerogen-rich zonal conversion response in a geologically descriptive finite element model. A sparse representation of polynomial chaos coefficients is highlighted in the process of computing summary statistics for the complex stochastically-driven TPME simulation results. Additionally, Monte Carlo (MC) simulations were performed in order to validate the results of the sparse NIPC representation. This is done considering MC is a widely recognized stochastic simulation process. Additionally, NIPC was used to illustrate the potential performance improvement that are possible, with a sparse polynomial chaos expansion enhanced by the incorporation of Least Angle Regression (LAR), as compared to MC simulation. Although the parametic uncertainty of the reaction-diffusion parameters of the Allen-Cahn was comprehensive, they did not accelerate the conversion timelines associated with the full zonal conversion of the kerogen-rich rock type in the statistical simulation results. By executing the stochastic simulations for a greater length of time the extent of full zonal conversion is examined in the RF modeling.
Development of Oil Based Foam for Pressurized Mud Cap Drilling PMCD Applications
Authors: Wu Qian , Penny Glenn , Rao Sai Sashankh , Mollica Juan , Samdani Ganesh Arunkumar , Ewelike Chioma , Zeilinger Sabine , Gupta Vishwas Paul
Published: September 2021

Pressurized Mud Cap Drilling (PMCD) technique is typically applied for drilling formations with natural fractures and large vugs that result in severe or total losses. The density of the drilling fluid used in PMCD is slightly below reservoir pore pressure. In the case of very low reservoir pressures below base oil densities (~6.7 ppg), foam can be an option. This paper presents a methodology to develop an oil-based foam system for a PMCD application. The scope includes the descriptions of a foam PMCD application, functional requirements of foam, the development workflow, testing procedures, and modeling that are necessary to qualify a foam for PMCD application. The development methodology first involves identifying the constraints and well conditions of a given PMCD application; these include wellpath, hole and casing sections, reservoir pressure and temperature, surface pumping pressure limits (typically a rotating control device limit), foam stability requirements, etc. The above constraints drive the performance requirements for the foam. Next comes the design of the foam formulation and evaluating its performance against these requirements through various lab tests and modeling efforts, which can include ambient pressure half-life tests for initial screening, static and rotational stability tests at in-situ well conditions, rheology tests, solubility tests, pressure transmission estimates, gas migration estimates, and hydraulics modeling. Example results from the lab tests and modeling are shown to provide more insights into the development process. The proposed methodology may be used as a guide to design a foam drilling fluid for a PMCD application. The iterative nature of the development method is shown and is driven by the functional requirements that are coupled to each other. For example, a more viscous foam may be more stable but it may not be pumpable. Likewise, a less viscous foam may be pumpable but may not be sufficiently stable. Similarly, a highly compressible foam may not be good at pressure transmission to monitor downhole pressure variations as compared to a less compressible foam. In summary, the methodology described in this paper explains the development of an oil-based foam for a PMCD application that satisfies a set of operational constraints and functional requirements while highlighting the major factors that could impact foam performance. The application of foam to PMCD is a new concept and to our knowledge has not been applied in the field; in significantly depleted reservoirs this may become a viable option.
Numerical RTA in Tight Unconventionals
Authors: Carlsen Mathias Lia , Bowie Braden , Dahouk Mohamad Majzoub , Mydland Stian , Whitson Curtis Hays , Yusra Ilina
Published: September 2021

We extend the numerically-assisted RTA workflow proposed by Bowie and Ewert (2020) to (a) all fluid systems and (b) finite conductivity fractures. The simple, fully-penetrating planar fracture model proposed is a useful numerical symmetry element model that provides the basis for the work presented in this paper. Results are given for simulated and field data.

The linear flow parameter (LFP) is modified to include porosity (LFPꞌ=LFP√φ). The original (surface) oil in place (OOIP) is generalized to represent both reservoir oil and reservoir gas condensate systems, using a consistent initial total formation volume factor definition (Bti) representing the ratio of a reservoir HCPV containing surface oil in a reservoir oil phase, a reservoir gas phase, or both phases.

With known (a) well geometry, (b) fluid initialization (PVT and water saturation), (c) relative permeability relations, and (d) bottomhole pressure (BHP) time variation (above and below saturation pressure), three fundamental relationships exist in terms of LFPꞌ and OOIP. Numerical reservoir simulation is used to define these relationships, providing the foundation for numerical RTA, namely that wells: (1) with the same value of LFPꞌ, the gas, oil and water surface rates will be identical during infinite-acting (IA) behavior; (2) with the same ratio LFPꞌ/OOIP, producing GOR and water cut behavior will be identical for all times, IA and boundary dominated (BD); and (3) with the same values of LFPꞌ and OOIP, rate performance of gas, oil, and water be identical for all times, IA and BD. These observations lead to an efficient, semi-automated process to perform rigorous RTA, assisted by a symmetry element numerical model.

The numerical RTA workflow proposed by Bowie and Ewert solves the inherent problems associated with complex superposition and multiphase flow effects involving time and spatial changes in pressure, compositions and PVT properties, saturations, and complex phase mobilities.

The numerical RTA workflow decouples multiphase flow data (PVT, initial saturations and relative permeabilities) from well geometry and petrophysical properties (L, xf, h, nf, φ, k), providing a rigorous yet efficient and semi-automated approach to define production performance for many wells.

Contributions include a technical framework to perform numerical RTA for unconventional wells, irrespective of fluid type. A suite of key diagnostic plots associated with the workflow is provided, with synthetic and field examples used to illustrate the application of numerical simulation to perform rigorous RTA. Semi-analytical models, time, and spatial superposition (convolution), pseudopressure and pseudotime transforms are not required.
An Experimental Investigation of Mass Transfer in Tight Dual-Porosity Systems
Authors: Alahmari Saeed , Jessen Kristian
Published: September 2021

During gas injection in ultra-tight fractured reservoirs, molecular diffusion can play a dominant role in the mass transfer process and enhance recovery by extracting oil components from matrix and delaying gas breakthrough. There has been a growing interest from scholars and operators to study the effect of diffusive mass transfer on the potential incremental recovery from CO2 and rich gas injection. However, many fundamental questions pertaining to the physics of multicomponent multiphase flow and transport are still left unanswered.

This paper aims to improve the understanding of multicomponent diffusive mass transfer between matrix and fracture blocks through experimental and modeling work. Displacement experiments were carried out using analog fluids and mesoporous medium to effectively isolate and study the relevant physical mechanisms at play. The experiments were performed in packed columns utilizing silica-gel particles that have internal porosity. The particle size is 40-70 micron with highly controlled internal pore size of 6 nm that makes up approximately 50% of the overall porosity. The quaternary analog fluids system consists of Water, Methanol, Isopropanol, and Isooctane, was used because it mimics the phase behavior of CO2, Methane, Butane and Dodecane mixtures at 2,280 psi and 100°C. Our selection of the analog fluid system and porous medium allowed us to investigate matrix-fracture fluid exchange as observed during an enhanced recovery operation in an ultra-tight fractured system. The effluents from these displacement experiments served as the basis for our analysis of diffusive mass transfer.

The role of molecular diffusion in the displacement experiments was investigated by first performing separate diffusion experiments to obtain diffusion coefficients for all relevant binary mixtures. Infinite dilution diffusion coefficients were measured for all binary mixtures and then used to model binary and multicomponent diffusion coefficients over the whole composition range. The accuracy of this approach was determined by performing additional binary diffusion experiments over a broader range of compositions.

The displacement experiments were simulated using an in-house simulator and excellent agreement was obtained: The extensive experimental/modeling work related to the diffusion coefficients of the analog fluid system was used in interpreting the diffusive mass transfer between the matrix (stagnant) and fracture (flowing) domains via a 1D linear model.

The presented work provides new insights into the role of diffusive mass transfer in ultra-tight fractured systems and builds a framework to highlight the critical data needed to effectively characterize and simulate recovery from such complex geological settings.
A Physics-Constrained Data-Driven Workflow for Predicting Coalbed Methane Well Production Using A Combined Gated Recurrent Unit and Multi-Layer Perception Neural Network Model
Authors: Yang Ruiyue , Liu Wei , Qin Xiaozhou , Huang Zhongwei , Shi Yu , Pang Zhaoyu , Zhang Yiqun , Li Jingbin , Wang Tianyu
Published: September 2021

Coalbed methane (CBM) has emerged as one of the clean unconventional resources to supplement the rising demand of conventional hydrocarbons. Analyzing and predicting CBM production performance is critical in choosing the optimal completion methods and parameters. However, the conventional numerical simulation has challenges of complicated gridding issues and expensive computational costs. The huge amount of available production data that has been collected in the field site opens up a new opportunity to develop data-driven approaches in predicting the production rate. Here, we proposed a novel physics-constrained data-driven workflow to effectively forecast the CBM productivity based on a Gated Recurrent Unit (GRU) and Multi-Layer Perceptron (MLP) combined neural network (GRU-MLP model). The model architecture is optimized by the multiobjective algorithm: nondominated sorting genetic algorithm Ⅱ (NSGA Ⅱ). The proposed framework was used to predict synthetic cases with various fracture-network-complexities and two multistage-fractured wells in field sites located at Qinshui basin and Ordos basin, China. The results indicated that the proposed GRU-MLP combined neural network was able to accurately and stably predict the production performance of multi-fractured horizontal CBM wells in a fast manner. Compared with Simple Recurrent Neural Network (RNN), Gated Recurrent Unit (GRU) and Long Short-Term Memory (LSTM), the proposed GRU-MLP had the highest accuracy and stability especially for gas production in late-time. Consequently, a physics-constrained data-driven approach performed better than a pure data-driven method. Moreover, the optimum GRU-MLP model architecture was a group of optimized solutions, rather than a single solution. Engineers can evaluate the tradeoffs within this set according to the field-site requirements. This study provides a novel machine learning approach based on a GRU-MLP combined neural network model to estimate production performances in CBM wells. The method is simple and gridless, but is capable of predicting the productivity in a computational cost-effective way. The key findings of this work are expected to provide a theoretical guidance for the intelligent development in oil and gas industry.
The New Development of Soft Microgel Particle Flooding Technology –From Theoretical Research in Laboratory to Field Trial
Authors: Sun Zhe , Wang Xiujun , Kang Xiaodong
Published: September 2021

Although polymer flooding technology has been widely applied and achieved remarkable effect of increasing oil. Yet the "entry profile inversion" phenomenon occurs inevitably in its later stage, which seriously affects the development effect. In recent years, the soft microgel particle dispersion is a novel developed flooding system. Due to its excellent performance and advanced mechanism, it can slow down the process of profile inversion, and achieve the goal of deep fluid diversion and expanding swept volume.

The soft microgel particle dispersion consists of microgel particles and its carrier fluid. After coming into porous media, it shows the properties of "plugging large pore and leave the small one open" and the motion feature of "trapping, deformation, migration". In this paper, reservoir adaptability evaluation, plugging and deformation characteristics of soft microgel particle dispersion in pore throat is explored by using the microfluidic technology and 3D Printing technology. On this basis, by adopting the NMR and CT tomography technology, the research on its oil displacement mechanism is further carried out. Furthermore, the typical field application case is analyzed.

Results show that, soft microgel particles have good performance and transport ability in porous media. According to the reservoir adaptability evaluation, the size relationships between particles and core pore throat is obtained, to provide basis for field application scheme design. Through microfluidic experiments, the temporary plugging and deformation characteristics of particles in the pore throat are explored. Also, when injecting soft microgel particle into the core, the particle phase separation happens, which makes the particles enter and plug the large pore in the high permeability layer. Therefore, their carrier fluid displace oil in the small pore, which works in cooperation and causes no damage to the low permeability layer. Furthermore, by using NMR and CT techniques, its micro percolation law in porous media and remaining oil distribution during displacement process is analyzed. During the experiment, microgels presents the motion feature of "migration, trapping, and deformation" in the core pore, which can realize deep fluid diversion and expand swept volume. From 3D macro experiment, microgels can realize the goal of enhance oil recovery. Finally, the soft microgel particle dispersion flooding technology has been applied in different oilfields, such as Oman, Bohai and other oilfields, which all obtained great success.

Through interdisciplinary innovative research methods, the oil displacement mechanism and field application of soft microgel particle dispersion is researched, which proves its progressiveness and superiority. The research results provide theoretical basis and technical support for the enhancing oil recovery significantly.
An Online Microcredential Certification Program to Upskill Petrotechnical Professionals in Data Analytics and Machine Learning with an Upstream Oil and Gas Industry Focus
Authors: Venugopal Kalyanaraman , Shastri Dvijesh , Radhakrishnan Suryanarayanan , Krishnamoorti Ramanan
Published: September 2021

The upstream oil and gas industry's digital transformation over the last few years has accelerated because of the COVID-19 pandemic. Data analytics and machine learning are key components of this digital transformation and have become essential skills for experienced petrotechnical professionals (PTPs) and aspiring entrants into the field. The objective of our work was to design and deliver a practical, engaging, and online microcredential certification program in upstream energy data analytics for PTPs.

The program was conceived as a collaboration between academia (University of Houston's UH Energy) and industry (NExT, a Schlumberger company). It was designed as three belt levels (Bronze, Silver, and Gold), each containing three stackable badges of 12 to 15 hours duration per badge. Key design points included

Identifying an online platform for administration Delivering convenient, interactive, live online sessions Delivering hybrid classes blending lectures and hands-on laboratories Designing laboratories using upstream datasets across various stages of oilfield expertise Administering test and quizzes, Kaggle competitions, and team projects.

The program contents were designed incorporating appropriate instructional design practices for effective online class delivery. The design and delivery of the laboratories using a code-free approach by leveraging visual programming offers PTPs and new entrants a unique opportunity to learn data analytics concepts without the traditional concern of learning to code. Additionally, the collaboration between academia and industry enables delivering a program that combines academic rigor with application of the skills and knowledge to solve problems facing the industry using the real-world datasets.

As a pilot program, all three badges of the Bronze belt were scheduled and successfully delivered during July and August 2020, as six 2-hour sessions per badge. From a total of 26 students registered in badge 1, 24 completed it, resulting in a completion rate of 92%. Out of these students, 19 registered and completed badge 2 and badge 3, resulting in the completion rates of 100%. Based on the success of the pilot program, a second delivery of the Bronze belt with 18 participants was offered from October 2020 through January 2021. All 18 participants completed all three badges. Feedback from participants attests to the success of the pilot program as seen in the following excerpts:

"A very good course and instructors. I have already recommended the course to a friend and I will continue to be an advocate for the course." "Teachers are very receptive to questions and it is a joy to hear their lectures." "I found the University of Houston course to be both highly engaging and incredibly informative. The course teaches basic principles of data science without being bogged down by the specific coding language."
Sand Mass Production in Anisotropic Stresses From Lab to Field Predictions
Authors: Papamichos Euripides , Walle Lars Erik , Berntsen Andreas Nicolas , Szewczyk Dawid
Published: September 2021

Sand onset and sand rate predictions are important in hydrocarbon production to optimize production, increase recovery, and reduce costs and the environmental footprint. Recent laboratory results on Castlegate sandstone from sand production tests in a True Triaxial test system have revealed that stress anisotropy plays an important role not only on sand onset but also in sand rate. The results confirmed our hypothesis that stress anisotropy means earlier sand produced but less sand. The laboratory results also revealed the effect of fluid saturation, i.e., oil, brine or irreducible water saturation on sand onset and sand rate. They allow the calibration of SandPredictor, a field sand prediction model, for stress anisotropy and production before and after water breakthrough. A field case analysis demonstrated the effects and showed the importance of in situ stress anisotropy and watercut on sand mass and rate.
High Resolution Solid State Acoustic Imaging for Advanced Well Integrity and Deformation Assessments in Conventional and Unconventional Wells
Authors: Littleford Thomas , Battistel Anthony , Simpson Greer , Wardynski Kacper
Published: September 2021

An advanced high-resolution acoustic imaging technology was deployed for well integrity and deformation assessments in both vertical and horizontal wells. This high frequency acoustic tool collected three-dimensional data quantifying deformation and wall thickness with resolution unobtainable by existing multi-finger caliper, magnetic flux leakage, and rotating single element ultrasonic systems. Several novel imaging methods are enabled by the high number of transducers (up to 512) on the imaging probe. These methods, including beam forming, beam steering and semi-stochastic multipulse imaging, are outlined and discussed in this paper. In addition, multiple types of standardized visualizations enabled by this high-resolution 3D data capture tool are introduced and examples of each are shown.

Lab qualification and imagery generated by the high-resolution solid-state imaging technology, when applied to various precision machined geometric anomalies, are presented. In addition to lab validation results, several field studies are showcased including assessments of ovalized casing, complex downhole corrosion, and isolated minor pitting. Leak paths, splits, and damaged regions within threaded casing collars were also identified, imaged, and quantified using the acoustic technology. Until now, these collar regions have been very difficult to image using legacy downhole tools due to fundamental limitations at the threaded connection geometry. Lastly, various downhole completion equipment case studies are presented showcasing several applications of acoustic imaging used to validate the set-position or condition of specialty downhole equipment. This paper outlines the usage of the solid-state acoustic technology to generate three dimensional geometry and wall thickness datasets with sub-millimetric resolution, providing operators with a holistic and actionable assessment of their well integrity.