bluuebunny/crossref_metadata_2025 huggingface dataset:
Creation of Automated Program for Calculating the Values of Target Indicators for Traffic Schedule Implementation
Authors: Ul'yanickaya Viktoriya , Ivanova Elizaveta , Isakova Dar'ya , Kishikova Aleksandra
Published: March 2023

Purpose: Achievement of the autonomy of calculations of target indicators for the implementation of passenger and suburb train schedule, decision-making and operational management, based on obtained calculations. Writing the program "Calculation of Target Indicator Values for Traffic Schedule Implementation" is due to the need to improve process implementation quality and to obtain maximal efficiency of planning and management system in a whole. Methods: Pascal programming language was used to automate the calculation of target indicators. Results: Creation and writing of independent software product with the preservation of organizational and mathematical methods of the work with information for to make managerial decisions. Practical significance: Automated calculation of target indicators for passenger and suburb train traffic schedule implementation will allow passenger complex all participants to consider the automation of the group of the processes related to information collection and processing on the process implementation "Train Traffic Schedule Implementation" through a single window. The proposed software product can be recommended for practical usage in the passenger complex of JSC "Russian Railways".
Topical Issues of Organizing Digital Department Activities in the Context of University Digital Transformation
Authors: Ermakov Sergey , Kucenko Sergey , Gil'vanov Rinat
Published: March 2023

Purpose: The stages of becoming in a university of new trend “Digital Department” which allows also to formulate term “digitalization” anew. Methods: The birth of term “digitalization” in a university has been studied. The evolution of notions “automation”, “informatization”, “digitalization” which predetermine smooth transfer to new trend in universities — “digital department” and, hence, “digital university”, has been shown. Results: “Digital university” model has been formulated that consists of such important components as “infrastructure”, “programmatic platforms”, “informational systems”, “data corporative storage” and “digital services”. “Digital department” possibilities in a university have been demonstrated in the part of realization of “Digital technologies on railway transport” educational program and such notional trends as internet of things, big data, virtual and augmented reality systems, artificial intelligence, “digital twin”, distributed ledger systems (recent years major trends in digital economy sphere). Practical significance: “Digital department” possibilities from the point of uniform approach to widescale teaching digital competences to students of almost all IT specialties and training trends have been demonstrated. The experience of external control has been narrated — from making to teaching — by Science and Higher Education Ministry and Digital Development, Communication and Mass Communications Ministry of Russian Federation by means of Innopolis University. The article authors make an attempt to answer topical in this sphere questions: how modern digital services immediately influence training features in professional education? Which is management model of “digital university”? Which components it consists of?
Habitus and labeling of at-risk school dropout children at the high school level in Lamongan Regency
Authors: Zahiroh Lana Faiqoh , Zenengene Maybe
Published: March 2023

Children who are at risk of dropping out of school are a social problem in the field of education. This study aimed to determine the habitus and labeling of at-risk school dropout children at senior high schools in the Lamongan Regency. The theoretical framework used was the Habitus theory proposed by Pierre Bourdieu and the Labeling theory by George Herbert Mead. This study employed qualitative methods. The informants in this study were high school students or equivalent. This study found that habitus among at-risk school dropout children leads to deviant behavior and labeling. This can encourage children to drop out of school. In addition, fields and capital also do not support children in studying. Children’s problems are also seen in the deviations committed both in the social and educational environment. That is what makes children have a label or nickname in society and their peer environment. This study can be used to inform government policies in the field of education, particularly in dealing with children prone to dropping out of school. In this case, the involvement of schools, teachers, parents, and the community is also essential.
The Imaginary Universe
Authors: Łukaszyk Szymon
Published: March 2023

Imaginary dimensions in physics require an imaginary set of base Planck units and some negative parameter cn corresponding to the speed of light in vacuum c. Fresnel coefficients for the normal incidence of electromagnetic radiation on monolayer graphene introduce the second, negative fine-structure constant α2−1≈−140.178 as a fundamental constant of nature and this constant introduces these imaginary base Planck units along with this negative parameter cn≈−3.06×108 [m/s]. Neutron stars and white dwarfs, considered as objects emitting perfect black-body radiation, are conjectured to possess energy exceeding their mass-energy equivalence ratios, wherein the imaginary parts of two complex energies inaccessible for direct observation make storing excess of these energies possible. With this assumption, black holes are fundamentally uncharged; charged micro neutron stars and white dwarfs with masses lower than 5.7275×10−10 [kg] cannot be observed; and the radii of white dwarfs' cores are limited to RWD<6.7933 GMWD/c2. A black-body object is in the equilibrium of complex energies of mass, charge, and electromagnetic radiation if its radius Req≈2.7665 GMBBO/c2.
Towards a Simulation Model Complexity Measure
Authors: Thompson J. Scott , Hodson Douglas D. , Grimaila Michael R. , Hanlon Nicholas , Dill Richard
Published: March 2023

Is it possible to develop a meaningful measure for the complexity of a simulation model? Algorithmic information theory provides concepts that have been applied in other areas of research for the practical measurement of object complexity. This article offers an overview of complexity from a variety of perspectives and provides a body of knowledge with respect to the complexity of simulation models. Key terms of model detail, resolution, and scope are defined. An important concept from algorithmic information theory, Kolmogorov complexity, and an application of this concept, normalized compression distance, are used to indicate the possibility of measuring changes in model detail. Additional research in this area can advance the modeling and simulation body of knowledge toward the practical application of measuring simulation model complexity. Examples show that KC and NCD measurements of simulation models can detect changes in scope and detail.
Level Weights for Modeling with Complex Survey Data
Authors: Natuhamya Charles
Published: March 2023

Introduction: Weighting is widely used in applied statistics especially while dealing with survey data. In recent years, multilevel modeling under complex survey designs has increased, resulting into demand for level weights. However, survey data that are accessible to the public for use usually do not contain level weights that are useful in multilevel modeling, but final survey weights that are only appropriate for single level analyses. In this paper, we demonstrate how the final survey weights can be used to estimate level weights for multilevel data analysis, and compare a model that applied level weights with one that applied the final survey weights. Methods: A framework for approximating level weights proposed by the Demographic Health Survey (DHS) program was used to estimate the level weights. Models were fitted using a multilevel mixed effects logistic regression method. Estimates from a model that applied survey weights was compared to those from a model that applied level weights. Results: Application of final survey weights instead of level weights underestimated standard errors and led to loss of precision of model estimates. Conclusions: Use of level weights produces estimates with high precision and yields correct values of standard errors hence appropriately informing inference.
A pilot Study to Assess Prescription Transfer and Medicines Collection through a New Electronic Prescription Service: A Cross-Sectional Survey
Authors: Tobaiqy Mansour , Ainousah Bayan E , Alorfi Nasser M , Alghamdi Alaa , Alqutub Sulafa Tarek
Published: March 2023

This study aimed to assess prescription transfer and medicines collection through Wasfaty, an electronic prescription service recently introduced in Saudi Arabia. A link to a cross-sectional online questionnaire was sent to all students and staff at the University of Jeddah, targeting beneficiaries who received e-prescriptions at the University Medical Centre (n = 2067). The questionnaire comprised 20 items under the following sections; demographics, patient perceptions and satisfaction with the Wasfaty service, and the availability of medicines. Of the 217 questionnaires received, the majority were filled by females (n = 125, 57.6%). Most were satisfied with the initial registration process of Wasfaty (n = 183, 84.1%). However, almost one-third of the participants reported that they could not find the prescribed medicines (n = 64, 29.7%), and most of them had to look for another pharmacy to obtain their treatment (n = 138, 63.9%). Respondents voiced their displeasure owing to the lack of access to certain pharmaceuticals, including anti-hypertensives and antidiabetics. This pilot study identified some challenges relating to the use of the Wasfaty service. Further attention to these challenges is required from the service providers, and a large-scale national study is warranted.
Quantum Machine Learning for Ocular Disease Recognition
Authors: Topaloglu Rasit Onur
Published: March 2023

In this paper we use quantum machine learning to detect and classify ocular diseases across age related macular degradation, cataract, diabetic, glaucoma, hypertension, and patological myopia categories versus a control group. We analyze fundus imagery from 1000 patients. Early findings indicate there may be benefit in terms of accuracy and loss function minimization of 2.07% and 1.979x respectively compared to a similar method implemented using traditional computers.
High Efficiency and High Stability for SHG in a Nd : YVO4 Laser with a KTP Intracavity and Q-switching through Harmonic Modulation
Authors: Afanador Delgado Samuel Mardoqueo , García López Juan Hugo , Reátegui Rider Jaimes , Aboites Vicente , Echenausía Monroy José Luis , Huerta-Cuellar Guillermo
Published: March 2023

In this paper, the stabilization and high efficiency of an unstable Second Harmonic Generation (SHG) of a Nd : YVO4 laser with a KTP intracavity is carried out by using a passive Q-switching crystal and a parametric modulation method (harmonic modulation) is shown. The harmonic modulation was defined as um(t) = Amsin(2π fmt), with modulation amplitude as Am(Vpp), and modulation frequency as fm(Hz), applied to the pumping of the Nd : YVO4 -KTP laser to control the amplitude and frequency of the emission, thus stabilizing the dynamic states of this laser. The promising application of this green light source is materialized when such light is necessary for high-density optics, such as in the treatment materials industry or in some aesthetic applications.
Strategy for Developing Cross-Border E-commerce of Yunnan Agricultural Products in the Context of “One Belt, One Road”
Authors: Huang Qiuchen , Chen Ji
Published: March 2023

Economic globalisation has promoted the extensive circulation of commodities around the world, and international trade has increasingly been a strong booster for economic growth in China. As an foundation for national economy, the shift of agricultural products (AP) from production to distribution has become the focus of agricultural development, and in recent years, the international trade of agricultural products in China has been the highest in the world. While, cross-border e-commerce (CBE), as one of the important modes of agricultural products circulation, has brought new opportunities for China's fresh agricultural products to carry out online import and export trade under the favourable policies continuously introduced internationally. This research analyses status of APCBE in Yunnan Province, China, and propose strategies for developing CBE of Yunnan AP.
Esfuerzos de conservación del manatí amazónico Trichechus inunguis (Natterer, 1833) en el Perú: una revisión actualizada
Authors:   , Dávila Pardo Camila Alejandra
Published: March 2023

Los manatíes cumplen un rol muy importante en los ecosistemas acuáticos en el Perú y el mundo. Son considerados especies clave por ser reguladores de la vegetació n flotante y además excelentes fertilizadores. El manatí amazónico (Trichechus inunguis; Natterer, 1833) es el ejemplar más pequeño dentro del orden Sirenia y es exclusivo de la cuenca Amazónica. Hoy en día es considerado una especie vulnerable, con una población que tiende al descenso. La presente revisión busca resumir la información disponible y actualizada sobre los esfuerzos de conservación del manatí amazónico en el Perú. Para ello, se revisaron un total de 70 documentos, tanto en inglés como en español, que tuvieran un enfoque de investigación basado en la conservación del manatí amazónico dentro de la Cuenca Amazónica. En Perú, desde el año 2001, se han tomado diversas iniciativas que buscan promover su conservación. Actualmente, Perú cuenta con investigaciones realizadas con respecto al manatí amazónico en el aspecto descriptivo y también con interés particular en su protección. Sin embargo, la información disponible es aún escasa y limitada en comparación con la de otros países en donde este animal se distribuye. La dificultad que hay para censar a la especie, principalmente por su característico comportamiento evasivo y las condiciones de su ambiente, como la turbidez del agua, y el color oscuro de esta lo que impide su visibilidad, restringen el desarrollo de más investigaciones. Estas investigaciones, con enfoque hacia la difusión de la información y conservación del manatí amazónico en todo su rango de distribución, han sido consolidadas de manera entendible en este artículo para facilitar el alcance de la información de las distintas estrategias y herramientas de conservación que se han ido incorporando a lo largo del tiempo en favor de la protección del manatí amazónico.
Plan de negocios de una plataforma digital para la contratación de servicios tecnológicos
Authors:   , Neira Sánchez Gabriela , Zegarra Polanco Lourdes Lida , Mendoza García Luis , Oyola Ruiz José Carlos , Vidal Tenorio Luis Miguel
Published: March 2023

En la actualidad muchas personas se encuentran trabajando en sus casas por una pandemia que lleva casi un año si consideramos el primer brote del COVID 19 en la ciudad de Wuhan – China, en Perú vivimos más de siete meses de aislamiento, en los que hemos dejado las oficinas para realizar todas nuestras actividades laborales en casa; algunas empresas, inmediatamente anunciada la cuarentena y el trabajo remoto enviaron equipos como laptops y/o PC’s a los hogares de sus empleados, otras les solicitaron que los vayan a recoger para que puedan continuar sus labores con “normalidad”. Las Naciones Unidas plantea entre los Objetivos de Desarrollo Sostenible el “Trabajo Decente y Crecimiento Económico” en base a dicho objetivo y ante la coyuntura generada por el COVID – 19 nace ALERTA PC S.A.C. una propuesta de negocio que consiste en la innovación en el modelo de contratación de servicios tecnológicos mediante el uso de una plataforma digital o APP. Alerta PC S.A.C. es un emprendimiento ideado por su actual Gerente General, quién también es uno de los cinco accionistas fundadores de la empresa, para satisfacer las necesidades de Lima Metropolitana en un principio y todo el mercado peruano en un mediano plazo. El usuario no tendrá que movilizarse para llevar sus equipos tecnológicos a un técnico cuando se descompongan, sino que mediante la aplicación (App) podrá solicitar los servicios de un técnico especializado con el respaldo de la empresa, en su domicilio o centro de trabajo o, si así lo prefiere, nuestra empresa recogerá y devolverá el equipo a su casa una vez reparado.
Aplicativo web para la comercialización de residuos sólidos y su impacto en la gestión ambiental en clínicas del distrito de SJL
Authors:   , Huaranga Valverde Yudmer Melvin
Published: March 2023

Esta investigación aborda el tema de la contaminación ambiental que generan las clínicas y que está causando situaciones alarmantes como la contaminación del suelo y aire. Debido a que no tienen un medio para vender sus residuos sólidos, el propósito de este trabajo es que las clínicas utilicen el medio tecnológico para comercializar los desechos que generan. Para esto se realizó la implementación de una aplicación web para realizar la actividad de comercio electrónico, de manera que el vendedor como y el comprador se sean beneficiados por la transacción. Se recolectó información de 15 clínicas para diversificar el público objetivo, donde se encuentra casos puntuales. Con el resultado que se ha acarreado del estudio pre y post-implementación que la investigación tiene, se verá la aceptación con el cuál se otorgará para todo tipo de empresas a nivel nacional.
Utilidad del índice framo en Geriatría: una revisión de la literatura
Authors:   , Shepherd Silva Pierina María , Sarmiento Chambi Kelly Fiorella
Published: March 2023

Objetivos del estudio: La fractura de cadera o fractura de fémur proximal es en la actualidad una de las principales amenazas para la salud de la población geronte, al ser la complicación de mayor importancia y severidad de la osteoporosis; por lo general es consecuencia de una caída, sin embargo, no se deben omitir los casos de aparición espontánea. Los factores de riesgo relacionados a sufrir una fractura de cadera se ven influenciados por los cambios propios del envejecimiento de cada persona, así como por las exposiciones domésticas y ambientales; usualmente el paciente típico que sufre una fractura de cadera es un individuo de la tercera edad en mal estado físico que padece de una patología sistémica. La fractura de cadera representa un considerable problema de salud debido a su elevada frecuencia, alta prevalencia, la morbimortalidad asociada, y las repercusiones económicas, sociales y asistenciales. La presente revisión de tema se llevó a cabo con el objetivo de determinar si el Fracture and Mortality Index (FRAMO) es una herramienta útil para ser aplicada en geriatría como un índice que permita identificar a aquellos pacientes geriátricos de alto riesgo que se beneficiarían con la implementación de medidas preventivas de mayor intensidad con el fin de disminuir la prevalencia de fractura de cadera y la mortalidad que con ella se asocia. Metodología y Resultados: Se realizó un estudio narrativo de revisión de tema, para lo cual se buscaron términos seleccionados en 8 bases de datos: PubMed, UpToDate, Google Scholar, Scopus, Wiley Online Library, SciELO, Hinari y EbscoHost…
Efecto de los arándanos (Vaccinium corymbosum L) sobre la presión arterial de adultos con hipertensión: Una revisión sistemática
Authors:   , Guerrero Justiniano Jean Carlo , Rios Escalante Cristian Martin , Trujillo Valverde Percy Antony
Published: March 2023

Objetivos: Determinar el efecto de los arándanos (Vaccinium corymbosum L) sobre la presión arterial en adultos con hipertensión. Métodos: Se realizó una revisión sistemática a través de la búsqueda de información en PubMed, Scopus y ScienceDirect el día 21 de octubre del 2020. Se incluyeron estudios clínicos aleatorizados en humanos mayores de edad y que investigaran el efecto de los arándanos en la presión arterial de personas hipertensas. La calidad de los estudios fue evaluada usando el manual Cochrane y para el reporte de los resultados se siguieron las recomendaciones PRISMA. Resultados: Tras la búsqueda de información, se obtuvo 865 artículos de los cuales se eliminaron 226 por ser duplicados, 624 luego de leer el título y resumen y finalmente 12 luego de la lectura del texto completo; quedándonos así, 3 estudios. De ellos, 2 no mostraron un efecto positivo en la presión arterial luego del periodo de intervención, el primero no muestra cambios significativos en PAS: -1,1±0,9 mmHg y PAD: -0,5±0,5 mmHg, valor de p no reportado; el segundo no muestra diferencias en ninguna de las dosis usadas tanto en la PAS: -0,63±2,93 mmHg (½ taza de arándanos) y -1,5±3,05 mmHg (1 taza de arándanos); p=0,65 y en la PAD: 1,3±1,38 mmHg (½ taza de arándanos) y -0,7±1,89 mmHg (1 taza de arándanos); p=0,24. Solo un estudio presentó mejoras significativas a través disminución de la PAS: -7±3 mmHg (p<0,05) y de la PAD: -5±2 mmHg (p<0,01). Conclusiones: Los resultados de esta revisión sistemática no muestran mejoras significativas de la presión arterial en personas hipertensas tras la suplementación de arándanos (Vaccinium corymbosum L.) en polvo liofilizado.
Impacto de la implementación de seguridad de la información mediante Amazon Web Services en el sistema de recursos humanos de Fractal SAC Lima - 2020
Authors:   , Apaza Quispe Luis Angel , Alarcón Ayquipa Ester , Ilizarbe Tito Eduardo
Published: March 2023

Debido a la demanda de información que se genera en estos días es necesario que sea proporcionada de forma segura, eficiente, eficaz y automatizada, dicho esto, es que se hace obligatorio implementar un recurso tecnológico que satisfaga estas necesidades, en nuestro caso hemos elegido cómo solución a una aplicación que se basa en Amazon Web Services (AWS). Esto nos servirá para resolver problemas de seguridad con respecto a la data en el sistema de Recursos Humanos de la empresa Fractal, también permite almacenar grandes cargas de información que nos ayudará ahorrar tiempo en el proceso y sobre todo en el ahorro de costos. En base a la seguridad de la información los conceptos que se hacen referencia en este trabajo de investigación contemplan la disponibilidad, integridad, confidencialidad, monitoreo y calidad de servicio, justamente Amazon Web Services se ajusta a estos preceptos, lo cual aporta de manera global a la solución en cuanto a la entrega y procesamiento de la información del sistema de Recursos Humanos en la empresa Fractal. Dado que Amazon Web Services es un servicio que se encuentra en la nube, cuenta con cualidades adicionales que permite un monitoreo constante, prevención de ataques, almacenamiento de grandes cantidades de información, revisión de tráfico de la red, etc. Este trabajo se fundamenta en el uso de tecnologías de la información no solamente para optimizar los procesos y resolver problemas de vulnerabilidades que puedan existir en el tratamiento de la información en un sistema, también cambia la forma de pensar que la seguridad de la información debería ser gestionada con los recursos inhouse y con una inversión grande en hardware, software y personal especializado. Es poner en practicar la disrupción digital en servicio de la sociedad.
Tratamiento del síndrome metabólico y reducción del nivel de fragilidad en adultos mayores según criterios de ENSRUD
Authors:   , García Alfaro Marco Antonio
Published: March 2023

En el 2014 un artículo de revisión de Chen y col. (1) ya mencionaba que lo metabólico sería un mediador en el marco de la inflamación crónica considerada mecanismo potencial dentro de la etiología del síndrome de fragilidad; y sugería observar la relación entre ambas entidades clínicas. Siendo pertinente, por tanto, sospechar que las mismas variables de dichos estudios u otras puedan comportarse de manera similar en nuestro medio. Desafortunadamente en nuestro país hay un número limitado de estudios en el tema, tomando principalmente estudios de prevalencia en cada uno de los síndromes por separado. De modo que al aun no quedar clara la relación entre ambos, es importante plantear nuevas estrategias con miras a implementar guías de prevención en este tópico. Así es como este estudio contribuiría a conocer mejor el tema en nuestra realidad. Sobretodo cuando se espera un incremento en las cifras de los problemas metabólicos, que de por sí es alta, como mencionaron Aliaga y col. en su artículo de 2014 sobre el tema centrado en adultos mayores del distrito de San Martín de Porres (2). Como se trata de una población con varias patologías asociadas usualmente, este estudio buscará responder a la interrogante de ¿el control favorable de los componentes del síndrome metabólico se correlaciona con una disminución en el nivel del síndrome de fragilidad entre los adultos mayores?
Definiciones de Síndrome de Fragilidad en Latinoamérica: un análisis bibliométrico
Authors:   , Campos Díaz María Isabel , Rubio Rodriguez Jorge Jean Paul
Published: March 2023

Objetivo: Describir las características bibliométricas de los artículos que proponen definiciones de Síndrome de Fragilidad en Latinoamérica. Método: Estudio bibliométrico, donde serán analizados estudios publicados en revistas ingresadas en la base de datos de SCOPUS y PUBMED en inglés y español. Estudio Bibliométrico sobre artículos que hayan sido publicados a partir del año 2000. Resultados: Encontramos 266 estudios, en primer lugar, Brasil con 70.04% y en segundo lugar México con 14.23%. El tema principal de la mayoría de los artículos fue “factores de riesgo para fragilidad” con 19.10% y el segundo fue “fragilidad como factor de riesgo” con 16.48%. En su mayoría fueron observacionales con 93.23%, experimentales 4.89% y las revisiones sistemáticas1.88%. Las universidades con mayor producción científica: Universidad de Sao Paulo con 10.53% y la Universidad Estatal de Campinas con 9.40%, ambas universidades brasileñas. El 82.33% de los artículos definieron la fragilidad como fenotipo, mientras que como índice 17.67%. Conclusiones: La población científica en países de Latinoamérica es mayor en Brasil y México. Aquellos estudios que hablan sobre fragilidad que hayan definido adecuadamente estas variables son en su mayoría de tipo fenotipo en comparación con índices. Además, el tipo de estudio observacional es el más utilizado para este tipo de investigaciones.
Asociación entre dependencia funcional y fragilidad con la frecuencia de hospitalizaciones en adultos mayores
Authors:   , Robles Guardamino Oliver
Published: March 2023

Objetivo: Determinar sí es que la coexistencia de fragilidad y dependencia funcional se asocia o no a mayor cantidad de hospitalizaciones en comparación a los pacientes que solamente presentan fragilidad o solo dependencia funcional, además de realizar un análisis estratificado por sexo. Materiales y métodos: Estudio observacional, analítico, de tipo cohorte retrospectiva analizando secundariamente la base de datos de un estudio cuya población fue compuesta por 1896 adultos mayores atendidos en el servicio de geriatría del “Centro Médico Naval” del Perú durante los años 2010 y 2015. El análisis de datos se realizó mediante el programa STATA versión 15.0. Resultados: Se observó relación estadísticamente significativa con la edad, la educación, el número de comorbilidades, la fragilidad, y la coexistencia de fragilidad y dependencia funcional, encontrando que, a mayor edad y multimorbilidad, mayor fue la cantidad de hospitalizaciones. Finalmente, con respecto al análisis entre la coexistencia de fragilidad y dependencia funcional con hospitalizaciones estratificado por sexo, vemos que tanto en hombres como en mujeres se mantuvo la asociación (p<0,001). Conclusiones: La dependencia funcional coexistiendo con la fragilidad se asocia con mayor número de hospitalizaciones en adultos mayores, esta relación se mantuvo tanto en hombres como en mujeres.
Efecto de la incorporación de materia orgánica en la respuesta fisiológica de la especie forestal Ficus benjamina para la mejora de la provisión de servicios ecosistémicos en el distrito de Chorrillos
Authors:   , Aguilar Tello Alisson
Published: March 2023

Ficus benjamina (Ficus) es una de las especies predominantes en los parques llamados bosques urbanos de Chorrillos, Lima, Perú. Esta contribuye significativamente con la mitigación del cambio climático y la mejora de la salud humana y medioambiental del distrito. El objetivo de este estudio fue evaluar la capacidad de la misma para almacenar carbono (C), fijar dióxido de carbono (CO2) y producir oxígeno (O2) en siete parques del distrito con diferentes estados de conservación y antigüedades, siendo estos: Rosario de Villa, La Pérgola, Antonio Garland, Las Gaviotas, Los Trovadores, Número Siete y Parque Fátima. Los rangos de C capturados fluctuaron en promedio de 2.16 hasta 9.71 t C/ha, secuestrando de 7.89 a 35.59 t CO2/ha y produciendo entre 5.75 y 25.89 t O2/ha para ecosistemas caracterizados por DAP que variaron de 29.73 - 58.14 cm y alturas entre 7.10 - 13.75 m. Simultáneamente, para conocer y cuantificar los efectos de la adición de materia orgánica en las respuestas fisiológicas que mejoran la provisión de dichos servicios ecosistémicos por la especie, se realizó un ensayo de invernadero con un diseño de bloques completamente aleatorizado (DBCA) donde se probaron tres dosis de compost (6.25%, 12.5% y 25%) y un control, cada una con ocho repeticiones. Dicho fertilizante presentó una buena relación C/N y cumplía con los estándares internacionales, sin embargo, poseía una alta salinidad y predominancia de huminas posicionándolo como uno de calidad media. Se evidenciaron indicios de clorosis, presencia de plagas y respuestas fisiológicas de crecimiento distintas en los componentes estructurales de Ficus.
Hallazgos radiológicos por resonancia magnética y actividad laboral en pacientes con diagnóstico de hernia discal lumbar atendidos en un centro de diagnóstico por imágenes en Lima, Perú entre 2014-2015
Authors:   , Laura De La Cruz Juan Carlos
Published: March 2023

La presente es una investigación de tipo observacional, descriptivo transversal, retrospectivo en el que se revisaron 385 resonancias magnéticas de columna lumbar de trabajadores operativos de construcción civil. Los resultados reportan que el 41% no presentó ningún hallazgo, el 49.6% presentó compresión del foramen neural, el 42.9% protrusión discal, el 18.2% prominencias discales, el 16.1%, estrechamiento de los recesos laterales y el 13.2% rectificación de la lordosis lumbar. Por otro lado el 58.4% presenta algún trastorno musculo esquelético y la presencia de dolor solo se reporta en el 1.3% de los pacientes. Mediante un análisis bivariado comparando características entre los grupos de pacientes con y sin trastorno musculo esquelético, se halló que el promedio de edad es mayor en el primer grupo, así como mayor pacientes con éste diagnóstico que tienen la condición de casados y mayor tiempo laboral, concluyendo que existen diferentes alteraciones en columna lumbar diagnosticados por resonancia magnética en trabajadores operativos de construcción civil atendidos en un Centro de Diagnóstico por Imágenes en Lima. 2014-2015.
Troll Reservoir Simulation Development, From Well Long-Term Tests to Full FMU Simulations
Authors: Reiso Edel , Bjørke Kjetil , Ek Torbjørn , Nybø Roger , Rivenæs Jan C.
Published: March 2023

Reservoir simulation studies of the Troll field, from the start with single realization full field simulation models and well simulation models in 1991 until today's complex and large ensemble models, have given important input to the Troll field development, reservoir management and well planning. The main focus in this paper is on Troll Oil simulation model. The effects of hardware and software technology developments are discussed. This includes challenges due to field size, geology, communications, thin oil zone, horizontal wells, gridding, numerics, CPU etc. Troll reservoir simulation has always pushed the limits of the hardware and the software, and this has initiated new solutions in modelling and simulators.

The following topics are addressed:

General information about the Troll field Troll Oil – how did it start Model size, grid resolution and hardware capacity – pushing the limits Grid construction Well modelling Geological reservoir model From Reference Model to Multiple Realizations
The Hybrid-Dimensional Darcy's Law: A Non-Conforming Reinterpreted Discrete Fracture Model (RDFM) for the Compressible Miscible Displacement and Multicomponent Gas Flow in Fractured Media
Authors: Xu Ziyao , Yang Yang
Published: March 2023

In this work, we develop a non-conforming reinterpreted discrete fracture model for the compressible miscible displacement and multicomponent gas flow in porous media containing high-permeability fractures and/or low-permeability barriers based on the hybrid-dimensional Darcy's law established in our previous work.

The key idea of the model is to describe the permeability of codimension-one fractures and barriers by the Dirac-delta functions. When there are only fractures, delta functions are added to the permeability tensor on the right-hand side of the Darcy's law. In contrast, when there are only barriers, delta functions are added to the inverse of the permeability tensor, which represents the resistance to fluids, on the left-hand side of the Darcy's law. When both appear, delta functions are contained on both sides by the principle of superposition. Thereby, we establish partial differential equations (PDEs) to model fluid flow in fractured porous media, which exempts any requirements on meshes.

We adopt the discontinuous Galerkin (DG) method to discretize the model in space and the second order implicit pressure explicit concentration (SIMPEC) method to march in time. The resulting non-conforming discrete fracture model is local mass conservative, flexible for complex geometry and easy to implement. The good performance of the method is demonstrated by several numerical examples.
Resolving Ambiguity in 2008-2015 Irving-Dallas Seismicity by Coupling Geomechanical Models at Fort Worth Basin and Barnett Reservoir Scales
Authors: Bubshait Abdulrahman , Jha Birendra
Published: March 2023

The activation mechanism of Irving-Dallas events is not well understood as it is shrouded in ambiguity due to many earthquakes located relatively far (>15 km) from production and injection wells. This requires a modeling approach that can quantify spatiotemporal propagation of production- and injection-induced stresses from wells to the faults while resolving fault geometry, stratigraphy, and well activity. However, constructing one such detailed model for the entire basin is computationally prohibitive due to the millions of grid cells needed to discretize the basin at that resolution. Based on our analysis of the data on well activity and fault position, we employed a novel two-model approach that exploits the disparity in scales between the basin-scale injection analysis and the well-scale fault reactivation analysis. We construct a coarse-scale model of Ellenburger injection in the Fort Worth basin and a fine-scale flow-geomechanics model of the Dallas-Irving region containing the faults that hosted the seismicity and the production/injection wells in the region. We use the coarse model to provide time-dependent pressure boundary conditions to the fine-scale model. We analyze the spatiotemporal evolution of pressure fields at both basin and reservoir scales. Analysis of the results provides evidence for interaction between Barnett's production and Ellenburger's injection as well as pressure diffusion from Ellenburger into the basement along the through-going faults. It allows us to test the hypothesis of injection-induced reactivation as the causative mechanism for the Irving seismic events. Almost all injection-induced seismicity studies in the literature show how injection near a fault (well-to-fault distance < 10 km) can induce seismicity. We provide evidence of far-field injection-induced seismicity (well-to-fault distance > 80 km) by coupling basin-scale and reservoir-scale models and a multi-physics approach.
An Integrated Modeling Framework for Simulating Complex Transient Flow in Fractured Reservoirs with 3D High-Quality Grids
Authors: Liu Hui , Liao Xinwei , Lie Knut-Andreas , Klemetsdal øystein , Bao Kai , Zhao Xiaoliang , Johansson August , Raynaud Xavier
Published: March 2023

Modeling near-well transient flow with complex 3D fracture networks poses several challenges: the multiscale nature (millimeters to kilometers), long and deviating well trajectories, intricate fracture networks with fracture-fracture and fracture-well intersections, and high level of reservoir heterogeneities. We address these difficulties by proposing a comprehensive methodology for meshing, discretizing, and simulating transient flow in complex 3D fracture networks based on discrete fracture-matrix models.

Our framework consists of three parts: (i) Given deviating wells and planar or nonplanar fractures and faults, we construct highquality 3D grids conforming to wells, hydraulic fractures, faults, and dominating natural fractures. We ensure sufficient mesh quality near important features using transfinite interpolation near wells and hydraulic fractures, combined with adaptive refinement in regions of interest. (ii) With the generated grid, we discretize the governing equations with a fully implicit finite- volume formulation with an inner-boundary well model and discrete fracture model. (iii) Finally, we analyze the results using suitable visualization tools, both for pressure-transient curves and 3D matrix/fracture data.

The framework enables high-resolution numerical modeling of transient flow with complex fracture networks in 3D. We demonstrate the capacities through simple validation cases with comparisons against an industry-standard commercial well-testing software but also present highly complex cases with long and deviating well trajectories and highly detailed fracture networks. We present and analyze flow-transient behavior coupling the wellbore, the fracture network, and the matrix. We also present an approach to reliably diagnose complex multiple flow regimes on the pressure-transient curves combined with different-scale spatial pressure distribution. Comparison against the commercial software indicates that our framework does not introduce adverse grid-orientation effects for non-K-orthogonal grids which is able to robustly handle the details for fracture-network heterogeneities in 3D reservoirs.

Overall, our framework is robust for simulating and analyzing realistic second-level transient effects and short-term well performance with complex fracture networks and heterogeneities. Detailed description of the 3D fracture networks, and accurate simulation of the near-well transient flow behavior can be achieved, which provides confidence to interpret the dynamic flow data at different scales and observe transport mechanisms in unconventional fractured reservoirs with multiple levels of heterogeneity.
Formation Fracturing by High-Energy Impulsive Mechanical Loading
Authors: Cao Wen , Younis Rami M.
Published: March 2023

Recent technological advances to trigger high-energy seismic waves from within the wellbore have spurred interest in their application to induce fracturing. While a considerable body of recent experiments at the bench scale (on the order of 1 cubic foot) show promise, there remains considerable uncertainty in how the process scales. This work characterizes the scaling relationships between the extent and intensity of fracturing stimulation and stress-wave characteristics. Our approach leverages direct numerical simulation of the elastodynamic equations accounting for nonlinear fracture mechanics. We apply a hybrid Finite-Discrete Element Method (FDEM) where cohesive (elasto-plastic) laws hold mesh elements together until complete failure. Beyond failure, elements act as deformable free bodies that can interact via contact constraints. An infinite domain is modeled with a spherical inclusion within which an impulsive load is imposed. The dynamic load models a rise time to a peak pressure, followed by a decay period, and all occurring within micro- to milliseconds. The model is validated with experimental observations at the bench scale after mesh-refinement verification. Finally, the model is used to explore the dimensionless parameter space by varying loading characteristics (rise time, peak pressure, and impulse) to reveal the stimulated damaged bulk volume and the crack intensity within it. At the bench scale, the model reproduces a nearly linear trend between damage radius and peak stress. Beyond that, however, the model predicts that this scaling slows considerably to a fractional power law between the damaged radius and the peak stress. This limitation is coincident with a geometric increase in the intensity of damage within the stimulated volume.
A Unified Thermal-Reactive Compositional Simulation Framework for Modeling CO2 Sequestration at Various Scales
Authors: Wapperom M. , Lyu X. , Nichita D. V. , Voskov D.
Published: March 2023

In this work, we present a unified framework for the simulation of CO2 sequestration problems at various time and space scales. The parametrization technique utilizes thermodynamic state-dependent operators expressing the governing equations for the thermal-compositional-reactive system to solve the nonlinear problem. This approach provides flexibility in the assembly of the Jacobian, which allows straightforward implementation of advanced thermodynamics. We validate our simulation framework through several simulation studies including complex physical phenomena relevant to CCUS. The proposed simulation framework is validated against a set of numerical and experimental benchmark tests, demonstrating the efficiency and accuracy of the modeling framework for CCUS-related subsurface applications. Important physical phenomena resulting from the complex thermodynamic interactions of CO2 and impurities with reservoir fluids can be accurately captured now in detailed dynamic simulation. The investigated simulation scenarios include a reproduction of lab experiments at the core scale, investigation of macro-scale analog model and simulation of large-scale industrial application. The simulation time can also span from hours to years among various applications. Complex thermal-compositional-reactive phenomena can be addressed at each of these space and time scales. The unified thermodynamic description allows us to perform all these simulations for a reasonable CPU time due to advanced parametrization techniques and efficient GPU capabilities in our in-house reservoir simulator DARTS.
A GPU-Accelerated Simulator for Challenging Extreme-Scale Geomechanical Models
Authors: Frigo Matteo , Isotton Giovanni , Janna Carlo , Spiezia Nicolò , Ferronato Massimiliano , Franceschini Andrea , Filippini Annachiara , Scrofani Giovanni
Published: March 2023

Simulation software is a very common tool to model geomechanical problems since direct measurements are extremely expensive and usually unfeasible. In addition, there is an increasing interest in simulating past events and forecasting future ones. Very fine meshes are needed to provide a realistic representation of complex stratigraphy. Hence the full exploitation of modern HPC infrastructure is mandatory. In this work, a fully parallel GPU-accelerated simulator for extreme-scale models is presented and its performance is assessed through a real basin scale model that is used as benchmark.
A Physics-Informed Neural Network for Temporospatial Prediction of Hydraulic-Geomechanical Processes
Authors: Zhang Chi , Wang Shihao , Wu Yu-Shu
Published: March 2023

This work aims to quantify the temporal and spatial evolution of pressure and stress fields in poroelastic reservoirs by replacing the conventional reservoir-geomechanical simulators with a novel convolutional-recurrent network (CNN-RNN) proxy. The proposed convolutional-recurrent neural network uses the governing equations of the coupled hydraulic-geomechanical process as the loss function. Initial conditions and spatial rock property fields are taken as inputs to predict the variation of pressure and stress fields. A customized convolutional filter mimicking the higher-order finite difference approach is adopted to improve the solution accuracy of the network.

We apply the neural network to solve one synthetic 2D hydraulic-geomechanical problem. The pressure and stress fields predicted from our neural network are compared with the reference numerical solutions derived from the finite difference method. The performance exhibits the potential of the proposed deep learning model for hydraulic-geomechanical processes simulation. The predicted pressure field displays a high degree of accuracy up to 95%, while the error in stress prediction is slightly higher due to the limitation of the current adopted neural network. In particular, our model outperforms the traditional second-order finite difference method in both speed and accuracy. Overall, the work shows the capability of the neural network to capture temporospatial prediction in hydraulic-geomechanical processes.
Pressure Jump Stabilization for Compositional Poromechanics on Unstructured Meshes
Authors: Aronson Ryan , Hamon Francois , Castelletto Nicola , White Joshua , Tchelepi Hamdi
Published: March 2023

While commonly used in practice for large-scale simulation of coupled subsurface flow and displacement, discretizations in which the solid matrix displacement is represented using linear, nodal elements and flow variables are represented as piecewise constants over each cell are not inherently inf-sup stable. This means that when undrained and incompressible conditions are approached, spurious pressure oscillations will appear in the numerical solution. This is particularly relevant in simulations of carbon sequestration, where the caprock above the injection location should be nearly impermeable. In this work we extend the idea of pressure jump stabilization to the compositional poromechanics setting in order to suppress these spurious oscillations. We apply this method to simulations of CO2 injection into a synthetic aquifer which is represented using a fully unstructured mesh. The results show that the stabilization is effective at smoothing the pressure field without adversely affecting the prediction quality of other quantities of interest.
Efficient Adaptation and Calibration of Ad	joint-Based Reduced-Order Coarse-Grid Network Models
Authors: Krogstad S. , Klemetsdal Ø. A. , Lie K. -A.
Published: March 2023

Network models have proved to be an efficient tool for building data-driven proxy models that match observed production data or reduced-order models that match simulated data. A particularly versatile approach is to construct the network topology so that it mimics the intercell connection in a volumetric grid. That is, one first builds a network of "reservoir nodes" to which wells can be subsequently connected. The network model is realized inside a fully differentiable simulator. To train the model, we use a standard mismatch minimization formulation, optimized by a Gauss-Newton method with mismatch Jacobians obtained by solving adjoint equations with multiple right-hand sides. One can also use a quasi-Newton method, but Gauss-Newton is significantly more efficient as long as the number of wells is not too high. A practical challenge in setting up such network models is to determine the granularity of the network. Herein, we demonstrate how this can be mitigated by using a dynamic graph adaption algorithm to find a good granularity that improves predictability both inside and slightly outside the range of the training data.