bluuebunny/crossref_metadata_2025 huggingface dataset:
Sosyal Medya Pazarlaması Alanındaki Yayınların Bibliyometrik Analizi (Bibliometric Analysis of Publications in Social Media Marketing)
Authors: Bilginer Özsaatcı Fatma Gül
Published: March 2023

Amaç –Bu çalışmanın amacı sosyal medya pazarlaması konusunda yapılmış araştırmaları bibliyometrik analiz yöntemi ile inceleyerek konuya ilişkin genel çerçeve çizmektir.Yöntem –Çalışmada Scopus veri tabanından faydalanılmıştır. “social media marketing” ifadesigeçen çalışmalar taratılmıştır. Alan sınırlaması olarak işletme , yönetim ve finans, sosyal bilimler ve multi disipliner seçilmiştir. Yıl sınırlaması yapılmamış ve 2009-2021 yılları arasında yayınlanmış toplam 1102 çalışma tespit edilmiştir. Doküman türü ve yıl sınırlandırılmamıştır. Bu şekilde tespit edilen çalışmalar R paket programı aracılığıyla çeşitli bibliyometrik analizlerle irdelenmiştir.Bulgular –Sosyal medya pazarlaması konusuyla ilgili 1102 çalışma çeşitli 507 kaynakta yayınlanmıştır. Çalışmaların ortalama alıntısı 21,32 dir. 1102 yayında toplamda 56982 referans yer almaktadır. İlgili çalışmaların anahtar kelime sayısı 981, toplam yazar sayısı ise 2426dır. Çalışma başına ortalama yazar sayısı 2,20, çalışma başına ortak yazar sayısı 2,61 ve işbirliği endeksi ise 2.56 olarak tespit edilmiştir.Çalışmaların %79’u makalelerden oluşmaktadır.Konuya ilgili en çok yayın yapan, en çok atıf alan ve en fazla iş birliği gerçekleştiren ülke ABD’dir. Sosyal medya pazarlaması çalışmalarda marka ve sosyal ağ konularının ön plana çıktığı tespit edilmiştir.Tartışma –Konuyla ilgili çalışmaların 2009’dan beri daimi arttığı tespit edilmiştir. Trendin bu şekilde devam edeceği ve gelecek yıllarda konuya ilişkin çalışmaların daha da artacağı düşünülmektedir. Konunun kavramsal yapısı pazarlama alanında toplanmıştır. Gelecekteki çalışmalarda sosyal medya pazarlamasına ilişkin yeni araştırma alanları ve odakların oluşturulmasının konuya zenginlik katacağı düşünülmektedir
Light Speed Expanding Hubble-Hawking Universe
Authors: U.V.S. Seshavatharam , S. Lakshmanarayana
Published: March 2023

Based on four major cosmological and astrophysical coincidences, it seems possible to develop a new model of Hubble-Hawking Universe having light speed expansion. Considering the analysis of 740 super novae data, it is possible to consider a constant rate of cosmic expansion. As there is no physical reasoning for the observed speed of light and all the cosmological observations are completely based on speed of light-by considering ‘light speed expansion’ as a characteristic nature of the universe, big bang, inflation, dark energy, quintessence and lambda term like ideal and unidentified concepts can be reviewed and relinquished at fundamental level and a practical model of expanding universe can be developed with ease and clarity. In this context, we would like to emphasize the point that, traditional definition of cosmic red shift is absolutely wrong. In terms of energy of photon, true cosmic red shift must be defined as - ratio of loss of energy in photon to the energy of photon at galaxy. We encourage the reader to see Figure 1 and Table 1 pertaining to light travel distances prepared with $\left(\frac{z}{1+z}\right)\left(\frac{c}{H_0}\right)\cong z_{new}\left(\frac{c}{H_0}\right)$. For data comparison, readers are encouraged to visit https://cosmocalc.icrar.org/ and http://www.atlasoftheuniverse.com/cosmodis.c. It may be noted that, considering 200 million solar masses as a cut off for ordinary gravity, dark matter can be considered as an effect of power law based super gravity of galactic baryonic mass. It is well believed that, Hawking’s findings about black holes are the most important contributions to physics in recent decades. Hence, we appeal the science community to recommend our Hubble-Hawking model for further research and study.
HTC-Grasp: A Hybrid Transformer-CNN Architecture for Robotic Grasp Detection
Authors: Zhang Qiang , Zhu Jianwei , Sun Xueying , Liu Mingmin
Published: March 2023

We introduce a novel hybrid Transformer-CNN architecture for robotic grasp detection, designed to enhance the accuracy of grasping unknown objects. Our proposed architecture has two key designs. Firstly, we develop a hierarchical transformer as the encoder, incorporating the external attention to effectively capture the correlation features across the data. Secondly, the decoder is constructed with cross-layer connections to efficiently fuse multi-scale features. Channel attention is introduced in the decoder to model the correlation between channels and to adaptively recalibrate the channel correlation feature response, thereby increasing the weight of the effective channels. Our method is evaluated on the Cornell and Jacquard public datasets, achieving an image-wise detection accuracy of 98.3% and 95.8% on each dataset, respectively. Additionally, we achieve object-wise detection accuracy of 96.9% and 92.4% on the same datasets. A physical experiment is also performed using the Elite 6Dof robot, with a grasping accuracy rate of 93.3%, demonstrating the proposed method's ability to grasp unknown objects in real-world scenarios. The results of this study show that our proposed method outperforms other state-of-the-art methods.
Compensation of Accuracy Error for Time Interval Measurements
Authors: Bespal’ko Vladimirs , Litvinenko Anna , Stepanovs Vsevolods , Kurtenoks Viktors , Smetska Viktorija , Lapkovskis Vjaceslavs
Published: March 2023

A method of accuracy error compensation for the time interval is examined, allowing to eliminate the dependence of accuracy error on the duration of measured intervals and minimising the influence of destabilising factors - ambient temperature changes and the initial deviation of the meter clock generator frequency from the nominal value. The compensation method is based on a calibration procedure that measures precise time intervals under conditions of changing ambient temperature. Then the dependence of the accuracy error on temperature for a particular meter is recorded. Based on these data, a correction table is compiled containing correction factors and temperature values at which these factors were determined. Under real measurement conditions, the correction factor corresponding to the current temperature is determined from the table for measured results correction. The table with correction factor values could be stored in the memory of the meter or processing computer. Experimental verification of the method showed that applying a correction for a meter with a standard XO class clock generator (certificated instability of ±50 ppm) can obtain an equivalent clock generator instability of ±0.15 ppm. The application of the method is efficient in cases where the use of high-end clocking to ensure the required measurement accuracy is not economically feasible.
Sex Age Annotated omics Data: Enabling powerful omics
studies
Authors: Guzzi Pietro Hiram , Cortese Francesca , Giancotti Raffaele , Lomoio Ugo , Puccio Barbara , Vizza Patrizia , Tradigo Giuseppe , Veltri Pierangelo
Published: March 2023

There is increasing evidence that many molecular processes exhibit differences with age 1
and sex. Such differences produces also differences in the insurgence and progression of many 2
complex diseases. For instances, demographic data on insurgence of comorbidities of mellitus 3
diabetes, on lethality of COVID-19, and on some cancers, shows differences between sex and age 4
groups. Therefore, the growing interest on such area requires the management of related data as 5
well as the development of algorithms and tool for the analysis. The availability of omics data 6
annotated with metadata related to age and sex is mandatory for building pipeline of the analysis. 7
The number of databases containing data related to age and sex is hencefort growing. We here show 8
some databases and tools storing such data. Finally, future research direction are highlighte
On an Indefinite Metric on a 4-Dimensional Riemannian Manifold
Authors: Razpopov Dimitar , Dzhelepov Georgi , Dokuzova Iva Rumenova
Published: March 2023

Our research is in the tangent space of a point on a 4-dimensional Riemannian manifold. Besides the positive definite metric, the manifold is endowed with a tensor structure of type (1,1), whose fourth power is minus the identity. Both structures are compatible and they define an indefinite metric on the manifold. With the help of the indefinite metric we determine a circle in different 2-planes in the tangent space on the manifold, we also calculate the length and area of the circle. On a smooth closed curve such as a circle, we define a vector force field. Further, we obtain the circulation done by the vector force field along the curve, as well as the flux of the curl of this vector force field across the curve. Finally, we find a relation between these two values, which is an analogue of the well known Green’s formula in the Euclidean space.
Understanding the Pathophysiology of Heart Failure with Mid-Range Ejection Fraction: A Comprehensive Narrative Review
Authors: Sotoudeheian Mohammadjavad , Hoseini SeyedAhmad , Mirahmadi Seyed-Mohamad-Sadegh
Published: March 2023

Heart failure (HF) diagnosis, phenotyping, prognosis, and treatment decisions are all based on the left ventricular ejection fraction (EF). Heart failure with mid-range EF (HFmrEF) is a third EF category for heart failure with an EF between 40 and 49 percent. Comparatively, heart failure with preserved EF or reduced EF has been largely unexplored. 10–25% of patients with HF have HFmrEF. Although HFmrEF has an intermediate clinical profile, it is more similar to HF with reduced EF, particularly because these patients have a high incidence of ischaemic heart disease. Heart failure with preserved EF has a lower risk of cardiovascular events than heart failure with reduced EF, which is milder. HFmrEF and HF with preserved EF patients have a similar or higher risk of non-cardiovascular adverse events than patients with HF with reduced EF. There is still a great deal of mystery surrounding HFmrEF. The purpose of this review is to describe the major pathophysiology of HFmrEF and its similarities and differences with the other two types of EF. It is the purpose of this paper to present a comprehensive overview of the currently available evidence in support of the pathophysiology of patients with HFmrEF. Further investigation of the pathophysiology, treatment, and prognosis of this condition will be needed in the future in order to better understand it.
The Effects of Antiperspirant Aluminum Chlorohydrate on the Development of Antibiotic Resistance in Staphylococcus epidermidis
Authors: Aras Ayse , Rizvanoglu Suna Sibel , Tanriverdi Elif Seren , Karaca Basar , Eryilmaz Mujde
Published: March 2023

This study investigates the effects of the antiperspirant aluminum chlorohydrate on the development of antibiotic resistance in commensal Staphylococcus epidermidis isolates. The isolates were exposed to aluminum chlorohydrate for 30 days, respectively. The bacteria that developed resistance to oxacillin, and ciprofloxacin were isolated, and the expression levels of some antibiotic resistance genes were determined by quantitative reverse transcriptase-PCR. Before and after the exposure, the minimum inhibitory concentration (MIC) values of the bacteria were determined by the microdilution method. A time-dependent increase was observed in the number of bacteria that developed resistance and increased the MIC value. Consistent with the ciprofloxacin resistance observed after exposure, an increase in the norA, norB/C, gyrA, gyrB, parC, and parE gene expressions was observed. In addition to aluminum chlorohydrate exposure, oxacillin resistance was observed in all test bacteria in the group subcultured only in the medium, suggesting that phenotypic resistance cannot be correlated with chemical exposure in the light of these data. The increase in mecA gene expressions of selected test bacteria that acquired resistance to oxacillin after exposure compared with control groups suggests that the observed resistance may be related to aluminum chlorohydrate exposure. To our knowledge, this is the first time in the literature that the effects of aluminum chlorohydrate as an antiperspirant on the development of antibiotic resistance in Staphylococcus epidermidis have been reported.
A pedagogia moderna na escola normal do Maranhão: orientações metodológicas para a formação das normalistas
Authors: Oliveira Rosângela Silva
Published: March 2023

Este artigo resulta da pesquisa ‘O mestre e a escola: lições de Pedagogia Moderna para o Estado do Maranhão com Antonio Baptista Barbosa de Godois, professor normalista em 1910’, vinculado ao Programa Institucional de Bolsas de Iniciação Científica da Pró-Reitoria de Pesquisa e Pós-Graduação da Universidade Estadual do Maranhão em parceria com o Fundo de Amparo e Pesquisa do Estado do Maranhão. O objetivo geral foi identificar as orientações didáticas da Pedagogia Moderna presentes na obra ‘O mestre e a escola’ publicada na capital maranhense na segunda década republicana e analisar as estratégias higienistas e pedagógicas citadas pelo autor para facilitar sua introdução na Escola Normal, consolidando a escola primária moderna no Estado do Maranhão. A metodologia desta pesquisa documental e bibliográfica aplicou a análise de conteúdos como técnica de coleta e tratamento dos dados que não se restringiram à análise da obra em estudo, mas estendeu a documentos oficiais do Estado do Maranhão, disponibilizadas ao público na seção de Obras Raras da Biblioteca Pública Benedito Leite localizada no centro da cidade de São Luis-MA. Em síntese, identificou-se uma congregação de doutrinas pedagógicas próprias para a nova demanda cultural republicana com advertências de que o ensino tradicional não respondia aos proclames formativos dos professores normalistas na sociedade moderna. Espera-se que a historicização produzida indique quais lições da Pedagogia Moderna foram introduzidas e posteriormente multiplicadas na instrução pública maranhense.
Structural features of a composite material produced by electric pulsed pressing from iron‑based multi‑component powder mixtures
Authors: Minko D. V. , Dyachkova L. N. , Pinchuk T. I.
Published: March 2023

The study is dedicated to the electric pulse pressing use for the composite materials production from diffusion‑alloyed iron powders. It is shown that the addition of a low–melting metal component, tin, has a positive effect on the compaction of the composite iron powder during electric pulse pressing. The density of samples from Dystaloy AB iron powder with the addition of 10 % tin reaches 7.3–7.5 g/cm3. It is impossible to obtain such a density in the conventional cold pressing process at a pressure of 100– 120 MPa. It is established that due to the short duration of thermal exposure during electric pulse pressing, diffusion processes do not have time to pass and the distribution of alloying elements in the iron base is uneven. A short thermal exposure causes oxidation of the surface of the powder particles, which also negatively affects the diffusion processes. Therefore, when obtaining alloyed powder materials by electric pulse pressing, the process must be carried out in a protective atmosphere. The revealed presence of a nanoscale substructure formed due to the effects of intense plastic deformation and temperature indicates the hardening of the powder composite material during electric pulse pressing. These features can be useful in the development of technologies alternative to the warm pressing of plasticized powders.
Features and practical experience in obtaining complex profile castings from aluminum alloys
Authors: Sadokha M. A. , Kryutsou A. V.
Published: March 2023

Variants of preparation of production of castings from aluminum alloys in conditions of single and small‑scale production are considered. It is established that in order to reduce the time and cost of obtaining castings, it is most expedient to carry out end‑to‑end design and manufacture of technological equipment using additive technologies and casting in sand‑resin molds obtained using the “no‑bake” technology.
Influence of gases on casting expansion processes during their hardening
Authors: Marukovich E. I. , Stetsenko V. Yu. , Stetsenko A. V.
Published: March 2023

It has been experimentally shown that directional solidification of water and bismuth in glass and quartz cylindrical forms does not result in expansion of the castings perpendicular to the solidification direction. Therefore, such forms are not destroyed. This is due to the unobstructed release of gases during directional solidification of water and bismuth. Gases have a great influence on the expansion processes of castings when they solidify.
Influence of various thermal conditions on the composition of high‑temperature diffusion oxides (satellite inclusions) in solid steel
Authors: Sidorenko T. I. , Ermachenok E. V. , Belash Yu. S.
Published: March 2023

The main goal of any modern production of long products is to ensure the required quality of finished products. One of the important quality indicators, along with mechanical and technological properties, is the quality of the rolled metal surface. The article presents the results of experimental studies of the composition of high‑temperature diffusion oxides formed on the surface of artificially deposited defects under various conditions of temperature exposure using the microrentgenospectral method on a scanning electron microscope with an energy dispersive microanalyzer. The characteristic features in terms of the percentage and presence of certain chemical elements in the scale of various steel grades have been established.
Ensayos sobre la pandemia
Authors: Chávez Juan Manuel , Di Laura Giancarla , Colina Ysea Félix José , Paredes Jorge , Durán Galdo Rafael
Published: March 2023

Ensayos sobre la pandemia reúne las experiencias y miradas de cinco destacados profesionales quienes, desde sus distintas áreas, reflexionan sobre las consecuencias personales de la pandemia. El escritor Juan Manuel Chávez y su testimonio desde la perspectiva del difícil reencuentro de un limeño residente en España, con su caótica ciudad natal en plena pandemia; la docente Giancarla Di Laura nos revela sobre el impacto que ha sido para las mujeres la propagación del Covid 19, siendo durante el confinamiento el período más terrible en el incremento de sus obligaciones y sobre exigencias físicas, mentales y emocionales; el educador venezolano Félix José Colina nos escribe sobre la vida del migrante en plena crisis sanitaria, asumiendo un punto de vista desde los valores humanos y lo espiritual; el comunicador Jorge Paredes Laos, explica sobre la obligada reinvención del ejercicio periodístico, para así lograr sobrevivir en medio de la más fuerte crisis mundial de la historia moderna; y Rafael Duran Galdo, ganador del concurso de ensayos sobre la pandemia convocada por nuestra universidad, hace un análisis crítico desde la fragmentación del sistema sanitario y la importancia de la revalorización de las ciencias sociales, con el fin de crear políticas públicas que promuevan un cambio en la salud de acuerdo con cada realidad y contexto histórico.
Efectos de la contaminación por agroquímicos en agua y suelo
Authors:   , Vivas Darío Guadalupe Doménica
Published: March 2023

En el presente estudio se realizó una revisión teórica de los efectos de la contaminación por agroquímicos en agua y suelo con el fin de dar a conocer a la sociedad de lo que puede ocasionar el uso desmedido de este compuesto químico. La industria agrícola usa estas sustancias para incrementar su producción y abastecer la demanda de las personas, sin embargo, se han podido evidenciar eventos relevantes que se acontecieron y causaron mucha conmoción en el hombre debido a los efectos que estas sustancias químicas estaban generando, no solo sobre el agua y suelo, sino que también impactaron a seres vivos que estuvieron en contacto con estas sustancias. Los efectos de los agroquímicos varían debido a su composición química y a los metabolitos que este pueda generar a partir de su degradación. Estos metabolitos pueden llegar a ser más tóxicos que la sustancia inicial. Además, los agroquímicos tienen la capacidad de bioacumularse y biomagnificarse en el ecosistema, por lo que persisten por mucho tiempo en el ambiente y sus efectos pueden llegar a ser letales; como en el caso de la pérdida de las aves por el uso de DDT en los años 50. Por otro lado, los impactos de estas sustancias dependen también de las condiciones climáticas, del tipo de suelo, las características físico químico del agroquímico y de su solubilidad en el agua. En resumen, estos compuestos químicos son considerados tóxicos para los factores abióticos y bióticos.
Modelamiento de las emisiones gaseosas provenientes del sector industrial
Authors:   , Rojo Ala Lina Candy
Published: March 2023

Las actividades que realiza el hombre son responsables del incremento de Gases de Efecto Invernadero (GEI), los cuales han generado el calentamiento global. El Perú es responsable del 0.4% de estas emisiones a nivel mundial , siendo el sector industrial uno de los mayores contribuidores en emisiones con 171,309.57 Gg CO2eq .Por otro lado, los gases que afectan la calidad de aire producto de la combustión generado por hornos y chimeneas no han sido estimado en porcentaje hasta el momento, estos son el dióxido de azufre (SO2) ,Monóxido de carbono (CO) y óxidos de nitrógeno(NOx) .El modelamiento es una herramienta que ayuda a simular la dispersión de estos contaminantes así como su comportamiento en la atmosfera ya sea que estas provengan de fuentes móviles como como los vehículos o fijas como las chimeneas, además que brinda información para solucionar los problemas en el deterioro de la calidad del aire y ayuda en la elaboración de medidas de mitigación, los tipo de modelos más usados son AEROMOD Y OCD el cual es usado en distintos países como Panamá y Colombia que lo utilizando para la vigilancia de calidad ambiental , los factores que han influido en el medio difusor son la topografía y vientos, además son utilizado por los Estudios de Impacto Ambiental (EIA) para la elaboración de la línea base ambiental.
Dependencia emocional y síntomas depresivos en mujeres víctimas de violencia familiar. Centro de Salud Mental Comunitario Virgen Asunta, 2020
Authors:   , Góngora Calvo Omar
Published: March 2023

La violencia hacia la mujer es una problemática social y de salud pública a nivel mundial, presente tanto en los países desarrollados y en desarrollo, (1) siendo la violencia doméstica, la de mayor prevalencia. (2) Según la Organización Mundial de la Salud (OMS), menos del 50% de las féminas son víctimas de violencia provocada por su pareja sentimental, (3) en América latina, las estadísticas son similares (29.8%) y en el entorno nacional, según la Encuesta Demográfica y de Salud Familiar el 63,2% de las mujeres con pareja han sido víctimas de violencia. (4) Por tanto, la violencia doméstica está relacionada con desenlaces trágicos en la salud, además, se ha identificado como un determinante para desencadenar patologías psicológicas, siendo principalmente los síntomas de ansiedad y depresión. (1,2,5)
El proceso de anulación del laudo arbitral en la Corte Superior de Justicia de Junín - 2017
Authors:   , Lopez Zaldívar Halley Esterhazy
Published: March 2023

La investigación se centra en analizar el comportamiento demostrado por la Sala Civil Permanente de la Corte Superior de Justicia de Junín en los procesos de anulación de laudo arbitral durante el año 2017, teniendo como objetivo el análisis de las principales incidencias que se hayan suscitado en su tramitación y resolución, particularmente aquellas orientadas al análisis de los actos que se constituyen en requisitos previos para la interposición del recurso de anulación, así como del análisis de la motivación de los laudos arbitrales. Para lograr tal cometido, se ha utilizado un enfoque cualitativo que nos permite estudiar el comportamiento desenvuelto por dicho órgano jurisdiccional, esto es, a partir de las consideraciones y decisiones expuestas en las sentencias judiciales emitidas en el año 2017. El análisis se ha realizado a partir de la revisión documental de las aludidas providencias judiciales, obteniendo como resultado la identificación de diferentes circunstancias que llaman poderosamente la atención respecto al conocimiento que los jueces tienen de la institución arbitral, así como la previsión de los efectos de las decisiones respecto a este tipo de materias. Finalmente, se concluye que la autoridad judicial, si bien puede haber logrado emitir una decisión arreglada a derecho, el camino seguido por ésta no resulta ser el idóneo en respeto de la autonomía del derecho de arbitraje.
Preferencias del paciente que acude al servicio odontológico privado respecto a los recursos humanos y físicos del consultorio dental
Authors:   , Otero Injoque Jaime Ignacio
Published: March 2023

Objetivo: Determinar las preferencias del paciente respecto a los recursos físicos y humanos de un centro dental privado en Lima Perú. Materiales y métodos: Se realizó un estudio cuantitativo descriptivo con carácter retrospectivo sobre una base de datos con información previamente recolectada empleando encuestas anónimas a una población de pacientes con fines de gestión. Dichas encuestas se recabaron en su momento en el lapso de dos años y fueron aplicadas de modo incidental en el Centro Odontológico Americano Las Gardenias. Se solicitó el permiso a la institución y se contó con la aprobación del Comité Institucional de Ética en Investigación de la Universidad Científica del Sur. Se realizó el análisis estadístico con el que se encontró las frecuencias y porcentajes de cada preferencia, se determinó el grado de asociación entre las variables con el test Chi cuadrado con nivel de significancia de P < 0.05 y se realizó una regresión logística para medir la influencia de la edad y el género del paciente sobre sus preferencias. Resultados: La información de 618 encuestas evidenció un nivel promedio de manifestación de preferencias de 80,91%, siendo que el horario para la cita, la delegación de funciones en el personal asistente y la privacidad de los ambientes fueron las preferencias que evidenciaron mayores frecuencias con valores de 91,75%, 89% y 89% respectivamente. La regresión logística identificó que la edad del paciente podría ser un factor que influye sobre las preferencias del día de la semana a ser atendido. Conclusiones: Los pacientes que requieren atención odontológica evidencian un alto grado de preferencias en relación a los recursos físicos y humanos del centro dental.
Enhancing Coiled Tubing Offshore Operating Limit Case Study
Authors: Sonawane Mahesh , Ge Michael Long , Toleman Benjamin , Campbell Mike
Published: March 2023

Coiled tubing (CT) is being increasingly used in open water mode for offshore light well intervention such as subsea hydraulic pumping applications. Traditionally coiled tubing has been popular in land based intervention applications; whereas for offshore applications using a CT deployed through a riser (in-riser mode) is very common.

However more recently, light well intervention (LWI) operations with CT deployed in open water mode are gaining traction due to improved efficiencies compared to traditional intervention methods. Coiled tubing systems are an integral part of a LWI system and are used for injection and hydraulic pumping operations.

In open water mode coiled tubing pipe is susceptible to direct hydrodynamic loading from waves and currents and vessel motions. The strength response and fatigue performance of the coiled tubing pipe can severely limit operability and increase down time for these operations when compared to riser based operations.

In this paper we will present a case study where coiled tubing has been used for LWI and subsea pumping operations. The paper will highlight some of the key challenges in design and operation of open water mode CT systems for offshore applications, from a loading standpoint and will also discuss challenges arising from lack of industry standards and codes. Analysis methodology and outcomes from this study will be presented to demonstrate how the CT strength response limits operations. Multiple mitigation options that were used to enhance operability will be discussed: these include judicious use of operational parameters, field measurement based environmental data and pipe depressurization to attain feasibility in harsh environments. In addition, modeling refinements based on 3 Dimensional (3D) Finite Element Analysis (FEA) of the CT injector guides and strain based design criteria will be discussed.

The paper will include recommendations based on experience from these case studies and highlight the need for a common industry standard to better assist Operators and OEMs with future designs.
High-Precision Automated Downhole Machining Tool with Real-Time Bit Position Measurement
Authors: Wiesenborn Kyle , Feliu Rodrigo
Published: March 2023

A new downhole machining system has been developed for lightweight intervention applications to remove wellbore obstructions and stuck valves, combining the precision of real-time bit position measurement with the power of push-pull forces up to 40,000 lbf. This tool builds on existing hardware from proven milling and shifting services, with added software features for advanced automation and control. This paper describes the new machining system and benefits for the operator to enable a reliable and robust contingency machining service.

Conventional wireline milling tools use a tractor tool for weight-on-bit and torque reaction. These tractor-based milling systems can be efficient for removing obstructions over a long interval, but they are not ideal for milling hard metal targets. For example, a nipple milling operation might require many hours to mill, during which time the operator has no indication that the milling operation is progressing as planned since the tractor does not provide any measurement of milling progress. The new machining system provides the operator with a real-time measurement of milling progress with resolution down to 1/100-in. to quickly diagnose and correct any problems due to bit damage, engagement with the target, or cuttings accumulation. For known targets of multiple materials or interrupted geometry, or for bits with staged cutting features, the direct measurement of bit position enables automatic machining programs that can autonomously execute a predefined sequence of cutting parameters (weight, speed, and torque) that change with measured bit position. The machining progress and quality indicators are displayed in real time at surface using a graphic interface showing the machining target and current bit position.

The machining tool uses the same anchor and linear actuator modules from wireline shifting service tools, combined with the same rotary motor and gearing modules from wireline milling service tools. Torque from the bit is transferred across the linear actuator module using a sleeve that is keyed above and below the piston. Both the linear actuator hydraulic motor and the rotary motor are equipped with rotor position and torque feedback and powered by a downhole inverter for maximum power efficiency, precise control of hydraulic pressure and bit position, and reverse operation for stall prevention and recovery.

Test data are shared in this paper to compare the performance of the new machining tool with a high-performing tractor-based milling service tool. Examples are given for both isolation valve machining and nipple machining.
Production and Well Access Restored After a Successful Subsurface Safety Valve Flowtube Milling on E-line, Preventing Major Rig Workover
Authors: Nobile Blanco Juan Jose , Prabhakaran Sudesh , Shiwan Shiwanshu , Rathod Chirag , Ting David
Published: March 2023

An offshore production well was out of operation after unsuccessful inflow tests. A remedial work plan was designed, but the execution resulted in severe damage to the top of the flowtube inside the Subsurface Safety Valve (SSSV), which was bent over and preventing production. Wireline conveyed mechanical intervention was performed with robotic tools to mill the obstruction and regain full bore access.

Downhole hardware milling is a common technology; however, a thorough process must be followed in order to succeed. The following factors were among those to be considered: well configuration (completion schematic and restrictions); the material of the flowtube (9CR-1MO Martensitic Steel); the risk of damaging the surrounding area; the risk of rotating the whole assembly while milling; and the risk of getting stuck with the e-line Bottom Hole Assembly (BHA). The milling intervention program was drafted taking into consideration different scenarios including contingencies.

E-line conveyed robotic milling intervention was the preferred option due to the urgency of the operation and high accuracy required to ensure the SSSV was left operational after milling. The robotic toolstring was first deployed for a drift run. Subsequent diagnostic runs were executed to help the team understand the downhole situation, adjust the operation plan and to test the performance of the tool downhole. Finally, the milling run was conducted showing a clear signature on the acquisition system, providing the parties involved with certainty regarding the outcome. A camera run was performed to verify the conditions of the operational area after milling. The job was executed in a total of four runs as per the program. Furthermore, the milling time itself was only 17 minutes. The complete removal of the damaged section of flowtube allowed the client to restore production immediately after testing the well integrity, with the SSSV fully functional.

This paper describes the complex yet efficient operation where a robotic milling tool, conveyed by e-line, was able to remove a critical downhole obstruction and restore production while preserving all safety features of the well, thus preventing a complex workover operation. The in-depth preparation, followed by a methodical execution, allowed oil production to be resumed in this well.
Alternative Approach to Liner Top Repairs
Authors: Carragher Paul John , Talapatra Didhiti , Vergel Pedro Antonio
Published: March 2023

Leaking and compromised liner tops have been a common ongoing problem in the oilfield. A poor cement job around the liner top can not only lead to gas or fluid migration from non-productive zones during the lifecycle of the well but can also severely limit remediation abilities by resulting in lower than desired frac pressures if the leak is substantial. The existing solution which involves squeezing cement is not only notoriously difficult but is also unreliable, time consuming, equipment heavy and fails to provide a gas tight seal if needed. This has over the years resulted in a very high number of leaking liner tops, a problem which needs a quick and reliable solution.
Pushing Coiled Tubing Design and Manufacturing Boundaries to Service 50,000-ft Mega-Reach Wells in Abu Dhabi
Authors: Galvan Irma I , Mallanao Genesis L , McClelland Garry , Rowland Ray , Novak Daniel
Published: March 2023

Extended-reach drilling target records in the Upper Zakum region have now reached 50,000-ft depth, surpassing manufacturing, equipment, and operational boundaries of the coiled tubing (CT) industry. However, custom-fit CT manufacturing equipment and logistical procedures are being evaluated to boost manufacturing capabilities that will allow to build multipurpose CT strings configurations with larger operating envelopes that can perform well across a variety of wellbore designs and target depths, including the recent record of 50,000-ft.

Over the past five years, highly engineered 2.375-in CT strings ranging from 31,000-ft to 43,000-ft in length have been deployed in the region, to service and maintain these complex wells trajectories over 4.5:1 MD/TVD ratios. The CT design makeups and length have progressed over time to have heavy reliance on extended reach hydraulic tractors by utilizing quench and temper materials that allowed greater diameter to wall thickness ratios (D/t), while satisfying pressure, load, and fatigue ratings. Nevertheless, the newest target depths require significant upgrades to CT manufacturing equipment, extended reach downhole tools and surface equipment.

CT has become an integral component to reduce cost and time in the region, and its utilization has increased because of the collaboration between the well operator, CT service providers, extended reach tool companies and CT manufacturers to improve its suitability, reliability, and predictability. The CT string engineering for 50,000-ft mega-reach wells required an iterative string design methodology that heavily considered the actual field reliability (actual tensile load ratings) of the CT hydraulic tractors and chemical friction reducers to determine the optimal CT lengths and wall thickness configurations. The CT manufacturing capabilities and surface equipment were maximized to optimize wellbore accessibility. A thorough evaluation of each stage of the CT manufacturing process revealed areas where equipment would reach capacity based on the CT design specifications. The resultant studies discuss comprehensive ground-up development, engineering, testing, and qualification of CT manufacturing requiring capital investments to produce the massive CT strings. The strings are 10 miles long weighing around 100 – 110 MT including the working drum. Funding for such a large-scale project is currently pending, with the operators’ demand for such strings and the projected return on investment influencing the decision.

The ability to intervene with CT is crucial to the field development strategy, and as the new wellbore designs become increasingly difficult to service, fit-for-purpose CT solutions are needed. CT manufacturing industry is engineering and developing equipment that expands the limits of CT production to bridge this gap.
Eliminating Bradenhead Pressure Using Novel Biomineralization Technology
Authors: Hiebert Dwight Randy , Griffin John
Published: March 2023

An oil well in Colorado had bradenhead pressure of 700 psi on the 9-5/8 in × 5-1/2 in annulus, prompting remediation to get bradenhead pressure below the 200-psi threshold set by the Colorado Oil and Gas Conservation Commission (COGCC) to resume production.

A biomineralization company was contracted by an operator in Colorado to apply their proprietary biomineralization technology to the well. Cement bond logs were used to identify a micro annulus around 3,050 ft. The well was prepared by setting a bridge plug at 3,062 ft, perforating at 3,056 ft and 3,052 ft, and running tubing to the depth of the bottom perforation. Biomineralizing fluids were then pumped into the well, where they formed crystalline calcium carbonate in the micro annuli.

After 36 hours of treatment, the injection rate dropped by several orders of magnitude. Subsequent monitoring by a state regulator determined bradenhead pressure had been eliminated and the well passed a mechanical integrity test without any additional intervention, allowing production to promptly resume.
Improved Bearing Design in Workover Motor Boosts Operational Efficiency for Plug Milling in North America
Authors: Unnikrishnan Vikram , Navin Guruswami , Breitenfeld Frank
Published: March 2023

Multi-stage stimulation in shale plays within North America land is still very predominant as of today and most operators continue with the already proven success of using frac plugs for zonal isolation. Post stimulation, intervention operation is carried out to remove the plugs via milling on coiled tubing or threaded tubing. Although dissolving or disintegrating plugs are gaining traction, vast majority is still of composite material and does require a proper bottomhole assembly (BHA) to ensure that the plugs are removed with maximum efficiency in one trip.

Coiled tubing (CT) service providers for milling frac plugs are using CT with an outer diameter (OD) ranging from 2" up to 2 7/8", with 2 5/8" becoming the new normal compared to the previous normal of either a 2" or 2 3/8". Primary driver behind the use of a larger pipe is to ensure that CT can get to the target depth (TD) with the required weigh on bit (WOB) as well as to maximize the pump rates for milling in long lateral wells (>15,000 ft lateral length), thereby minimizing the need for short trips during the entire milling process. This increased flow rate and extended reach requirement in turn leads to the need for a more robust workover motor (WOM) that can handle the additional set down weights imparted on the BHA. Traditionally the WOM were derived from drilling services, where the process of hole making and stress acting on the motor is a lot different than the plug milling operations. Due to these differences, the reliability of the WOM can get compromised, which in turn will impact the operational efficiency.

This paper will discuss the steps incorporated to prevent drive sub failures, which were mostly caused due to the combination of bending load and torque transmitted by unwarranted stalling. The overload would cause a loss in compression around the upper radial bearing, which eventually leads to drive sub failing. Improvement potential was identified by increasing material strength and optimizing contact areas. Extensive modelling was carried out to improve the design, and materials with improved strengths were identified. Further, improvements were also incorporated into the lower thrust rings, both inner and outer. Field trials were conducted and based on the modifications, it was observed that the WOM failures were eliminated, thereby completing the mill outs in a single trip.

Improved design and material selection, helps in providing excellent service delivery, which in turn reduced the OpEx for customers carrying out plug milling in North America.
Completion Leak Repair with Corrosion Resistant CT Velocity String
Authors: Aguirre Erick , Nebiolo Martin
Published: March 2023

An operator company in Bolivia needed a solution to a corrosion and pressure integrity problem caused by the presence of CO2 gas in the production fluids, resulting in deep tubing corrosion over certain sections of completion components with measured penetrations up to 96% of tubing's wall thickness.

Based on the corrosion's profiles, the intervention objective was to install a 16% chrome corrosion-resistant velocity string inside the production string to produce the well avoiding the exposure of those highly corroded components from the tubing.

The repair intervention concept was to set a hydraulic packer over the lower completion below the most compromised section of the production string and connect the isolation packer with 2" OD 16%Cr coiled tubing pipe up to the surface, hanging the string on the wellhead.

The velocity string installation should be performed in a single run with the well in live condition, avoiding the need to kill the well during the intervention.

The well's lower completion was composed of TPC-fired guns, a combination of 2-7/8" 6.4# and 3-1/2" 9.2# N80 tubing, and a 7" 23-29# packer. The upper completion was basically an arrangement of 3-1/2" 9.2# N80 tubing with a retrievable SSSV set at 107 m, a sliding sleeve device, and a seal unit sub to connect the upper to the lower completion.
Subsea Well Annular Integrity Repair Using Coiled Tubing and Pressure Activated Sealant
Authors: Johns Joel E. , Anderson Chris , Anguiano Juan A. , Jones Steven
Published: March 2023

Production from a subsea well was halted due to hurricane activity in the Gulf of Mexico. When the well was returned to production, the annulus experienced a loss of pressure integrity. To achieve regulatory compliance and return the well to production, annular integrity had to be restored in a safe, expeditious manner. This paper will describe the process of operations undertaken to cure this well integrity issue utilizing pressure activated sealant deployed via coiled tubing.

Pressure activated sealants have been utilized for a number of years to efficiently cure leaks in a wide variety of applications. One of the first challenges to be addressed when considering a sealant repair is the method of getting the material to the leak site. For the purpose of the subsea well in question, coiled tubing was used to convey the sealant to the sea floor from a service vessel. An ROV then connected the coil to an external tree cap via a flying lead after which the sealant was introduced to the annulus by lube and bleed pressure cycles.

The annular integrity issue was analyzed in an effort to determine leak severity and location. Pressure trends noted at annular pressures of 4000 psi indicated a leak ranging from 0.15 – 1.5 lit/min. Gradient analysis indicated that the leak was deep in the completion potentially at a liner lap or the packer. Based on this information a sealant blend approximately 2 ppg heavier than the completion fluid was developed for the purpose of curing the leak. An external tree cap was installed on the well in order to provide access to the annulus of the well via a hot stab connection. About eleven cubic meters of sealant was transferred to the annulus through 2" coiled tubing extended to the sea floor connected to the well via a flying lead. A series of lubricate and bleed cycles were performed to accomplish this without exceeding predetermined pressure limits. After allowing the sealant to settle on the packer, annular pressure was maintained to allow the sealant to cure at the leak site. The pressure differential at the leak caused the liquid sealant to form an elastomeric seal. A positive pressure test was obtained shortly after the process and the well was returned to production.

An example of how using pressure activated sealants designed to polymerize only at a leak site affords options to expensive workovers on subsea wells will be provided herein. The use of this technology in concert with coiled tubing deployment represents an expeditious, economic approach to solving complex well integrity issues.