bluuebunny/crossref_metadata_2025 huggingface dataset:
Inversión en infraestructura y demanda turística: una aplicación del enfoque de control sintético para el caso de Kuélap, Perú
Authors: Lahura Erick , Sabrera Rosario
Published: June 2021

¿Cuál es el efecto de la inversión en infraestructura sobre la demanda turística? Para responder a esta pregunta, se analiza el caso del Complejo Arqueológico Kuélap, el cual se ha hecho más atractivo y accesible luego de la construcción del primer sistema de telecabinas del Perú y de la reconstrucción del aeropuerto de Jaén. La hipótesis que se plantea es que dicha inversión en infraestructura ha tenido un efecto positivo e importante sobre la demanda turística de Kuélap. Para evaluar la validez de esta hipótesis, se aplica un estudio de caso comparativo en el cual se utiliza un “control sintético” construido a partir de la información de los diferentes sitios arqueológicos del Perú similares a Kuélap. Este control sintético permite estimar cuál hubiera sido la evolución de las visitas a Kuélap si no se hubiera realizado la inversión en infraestructura turística. De esta forma, el efecto causal de dicha inversión es la diferencia entre las visitas observadas y las visitas del control sintético. Los resultados muestran que la inversión en infraestructura turística generó un aumento de aproximadamente 100 por ciento en el número de visitas a Kuélap.
Crónica de la economía peruana en tiempos de pandemia
Authors: Vega Jorge
Published: June 2021

En este artículo se analiza la evolución de la pandemia del virus COVID-19 en el Perú, desde mediados de marzo de 2020, en que se inicia la cuarentena nacional obligatoria, hasta el 16 de octubre del mismo año. Se muestra la doble crisis sanitaria y económica ocasionada por esta pandemia en el país, que ha ocasionado elevadas tasas de infección y mortandad entre la población nacional, y ha generado enormes pérdidas de producción y empleo, nunca antes vistas en la historia económica y sanitaria nacional. En comparación al resto del mundo, el Perú registra la mayor tasa de personas fallecidas a consecuencia del virus, y está asimismo entre los primeros países con mayor cantidad de personas infectadas a nivel mundial. En términos económicos, la contracción del PBI de Perú durante el presente año, será superior a la de los demás países de América Latina; mientras que la tasa de desempleo podría llegar hasta el 28.3% de la fuerza laboral del país. Estos penosos resultados son consecuencia de, por un lado, la debilidad del sistema de salud pública nacional existente antes de la pandemia, y, por otro lado, de las rigurosas medidas de confinamiento de personas y el cierre obligatorio de numerosas actividades económicas, para tratar de reducir la propagación del virus entre la población nacional. Luego de siete meses de extrema crisis sanitaria y económica, periodo durante el cual se reforzó la infraestructura de salud y se otorgaron diversos estímulo fiscales y crediticios, que en conjunto representan el 14% del PBI, hay actualmente indicadores que muestran que la peor parte de la turbulencia ya habría sido superada. Los sistemas hospitalarios ya cuentan con cierta holgura para atender a los pacientes infectados; se han reducido las tasas de positividad o presencia del virus entre la población analizada; se ha iniciado la progresiva reapertura y reactivación de diversos mercados y empresas y se han empezado a recuperar paulatinamente, los millones de empleos perdidos durante el período analizado. Ello no significa, sin embargo, que la crisis esté finalmente bajo control, ya que existe la posibilidad de algún rebrote de la epidemia, lo cual desencadenaría un nuevo ciclo económico recesivo, similar al experimentado en meses anteriores. El país y las autoridades de gobierno deberían de aprender la lección, y no descuidar la inversión en salud pública, de la manera como lamentablemente se hizo durante muchas décadas, por sucesivos gobiernos.
Sacralizar el acto médico. Valores éticos y profesionales entre medicina y farmacia, Colombia, 1894-1914
Authors: Márquez Valderrama Jorge , Estrada Orrego Victoria
Published: June 2021

En Colombia, la historia de la profesionalización es un problema poco explorado. La historia social de las ciencias y la sociología de las profesiones nos aportan una base para interrogarla. Este artículo parte de dos preguntas: ¿Cuáles son y cómo han operado las relaciones y confrontaciones entre profesiones y oficios médicos y afines, en el proceso histórico de la profesionalización de la medicina? y ¿cómo se ha manifestado e influido en ese proceso el discurso ético? Para ilustrar la legitimación del monopolio del ejercicio de la medicina en Colombia, se estableció un corpus de discursos y debates sobre la profesionalización, con énfasis en enunciados sobre la ética como defensa de la profesión. Esos discursos fueron publicados en las principales revistas de medicina y farmacia del país, entre 1894 y 1914. El corpus muestra que los argumentos médicos en favor de un monopolio del ejercicio de la medicina son, además de científicos y económicos, políticos y éticos. Se inscriben en una argumentación en que se combinan reflexiones sobre las cualidades morales de los médicos, así como su legitimidad en la administración de la verdad y su necesidad de ejercer poder en la delimitación de la profesión.
Saberes médicos, prácticas y espacios de la curación al sur del Virreinato del Perú. Córdoba del Tucumán, 1573-1650
Authors: Tapia Justo Roque
Published: June 2021

El artículo tiene por objetivo estudiar parte de los efectos del proceso de circulación de los saberes médicos en la jurisdicción de Córdoba –gobernación del Tucumán– a fines del siglo XVI y principios del XVII. Para ello, se indaga en los entornos materiales de las prácticas médicas y en el conjunto de los oficiales que actuaron en el marco de dichos entornos, mediante un microanálisis anclado en documentos inéditos procedentes del Fondo de Justicia del Archivo Histórico de la Provincia de Córdoba y en las ediciones de las Actas del Cabildo de la ciudad. Se sostiene que en los espacios de curación distinguibles en la jurisdicción cordobesa del período delimitado se conformó un repertorio de saberes en el cual la etiología humoral articuló conocimientos de procedencia más bien erudita con otros que formaban parte del saber-hacer de cada oficial adquiridos mediante la práctica directa.
Editorial. Historia Sociocultural de la Medicina y la Salud en América Latina. Siglos XVI al XX
Authors: Martínez Martín Abel Fernando , Otálora Cascante Andres Ricardo
Published: June 2021

Editorial
POÉTICA DA AUTOFICÇÃO NA PERSPECTIVA YIN YANG E UMA MICROCULTURA DIALÉTICA E HOLÍSTICA DO CORPO
Authors: Ziegler André Martins
Published: June 2021

O artista-pesquisador contemporâneo, que investiga poeticamente sobre a sua própria corporeidade, depara-se muitas vezes com questões paradoxais por tensionar os sentidos das relações que o estabelecem no mundo. A partir dessa percepção, essa escrita pretende refletir algumas questões a respeito de uma poética da autoficção pela perspectiva do Yin Yang. Já que está poética evidencia uma corporeidade que a todo momento articula imagens paradoxais em um processo de sensibilização e constituição de uma micropolítica holística e dialética do corpo.
SOBRE A PROPOSIÇÃO DE UMA PRÁTICA PEDAGÓGICA DO SUJEITO NOMEADO COMO ARTISTA-PROFESSOR
Authors: Cansi Lislaine Sirsi
Published: June 2021

O presente artigo compõe-se em uma escritura narrativo-reflexiva. O artista-professor, sujeito que protagoniza a história, observa o universo escolar e propõe uma prática pedagógica para o Ensino da Arte. A proposição de ordem reflexiva e voltada para a sala de aula escolar advém de certa experiência do artista-professor com sua poética. Dessa experiência, a categoria “corpo” norteia a proposta pedagógica. Autores como Félix Guattari (2012), Gilles Deleuze (1992), Jorge Larrosa (2015), John Dewey (2010) e Katia Canton (2001; 2004; 2012) fundamentam o pensamento do artista-professor.
DANÇA NO CONTEXTO ESCOLAR: ANTIGAS E NOVAS QUESTÕES
Authors: Duarte Gustavo De Oliveira , Castro Daniela Llopart , Silva Daniela Grieco Nascimento e
Published: June 2021

O texto aborda o ensino de Dança na Escola a partir do Programa Institucional de Bolsas de Iniciação à Docência (PIBID) realizados na Universidade Federal de Pelotas (UFPel/RS) e na Universidade Federal de Santa Maria (UFSM/RS). Problematizamos experiências didático-metodológicas a partir de um trabalho de intervenção na área de Artes das escolas envolvidas. Os resultados apontaram significativa relevância tanto na formação inicial dos pibidianos quanto na formação continuada dos professores das Escolas. Temáticas transversais articularam os conteúdos trabalhados com a prática social. A Dança como área de conhecimento na Escola pode contribuir na formação estética da comunidade escolar e no desenvolvimento estético-crítico do educador.
O APRENDIZADO INFORMAL DA DANÇA K-POP: JUVENTUDE, TRANSCULTURALIDADE E PERFORMANCES DE GÊNERO
Authors: Andreoli Giuliano Souza , Fernandes Braçi
Published: June 2021

O objetivo deste artigo, apoiado em pesquisa de campo de inspiração etnográfica, é investigar o perfil dos grupos de Covers de dança K-pop na cidade de Porto Alegre. Buscou-se compreender como os produtos da Indústria Cultural afetam os processos de aprendizagem e criação em dança. Os dispositivos metodológicos construídos foram observações participantes, acompanhando ensaios e eventos de grupos e coletivos culturais. O estudo tomou como base teórica autores como Martín-Barbero, Mafessoli e Butler, para discutir temas como cultura pop, juventude, identidade, neotribos e performances de gênero. Concluímos que os produtos da indústria K-pop potencializam processos informais de aprendizagem e a sociabilidade entre jovens em suas diferenças de gênero, à margem da cultura hegemônica de dança.
DE TER INVEJA DAS VEIAS DO CACHORRO
Authors: Aleixo Daniel Ribeiro Fernandes , Ferreira Pedro Ernesto
Published: June 2021

O presente texto é uma tradução do manifesto escrito por Tatsumi Hijikata publicado no Japão em 1969, originalmente intitulado Inu no jo myakuni shitto suru koto kara (犬の静脈に嫉妬することから). A versão da qual os autores se basearam para a tradução é a publicada em inglês pela revista TDR/The Drama Review Spring 2000, Vol. 44, No. 1 (T165), pp. 56–59. O manifesto De ter inveja das veias de um cachorro é posterior a apresentação mais importante da carreira de Hijikata no que diz respeito à dança butô, a chamada Revolta da Carne (1968). O texto segue uma linha de pesquisa do dançarino em relação a um corpo feito de carne que depende do mínimo para se movimentar e consegue escavar sua potência de movimento para a dança através da debilidade e da doença. Nesse momento, Hijikata passa a se interessar mais pelos corpos socialmente doentios e desligados da saúde para desenvolver sua ideia de corpo debilitado, ou suijakutai (衰弱体).
CHICKEN-AND-EGG DILEMMA BETWEEN INCOME AND ALMS: REVIEW OF ISLAMIC PERSPECTIVES
Authors: Nurjanah Fitri , Sakinah Mutiara , Muhammad Askar
Published: June 2021

Indonesia is the most generous country in the world. This is evident from the World Giving Index created by the Charities Aid Foundation which has placed Indonesia in the number one position in the world in 2018. There is an increase compared to the previous year, where Indonesia was in second place after Myanmar. The main indicators are the level of donating money, helping foreigners, and participating in volunteer activities. On the other hand, the World Bank in 2018 placed Indonesia in the sixteenth position based on GDP Current USD and the eighth position based on GDP PPP Current USD. This proves that income is not the main thing that encourages someone to give alms. However, it is still uncertain whether income and level of alms correlate with each other. Jones and Posnett (1991) revealed that an increase in the behavior of giving alms is not in line with an increase in household income. On the other hand, there is a significant positive relationship between income and a person's level of alms (Arshad, 2016). The two types of research mentioned (Jones and Posnett, 1991; Arshad, 2016) conducted testing at the micro level. Therefore, this research will concentrate more on the macro level. Pharoah and Tanner (1997) explain that people who consider religion important in their lives tend to give more. This study uses a quantitative approach to test the correlation between the World Giving Index and GDP using the Spearman rank correlation test. The Spearman rank correlation test measures the correlation between two random variables based on ranking order. The author has found that there is no correlation between high income and the desire to give alms. This research can be used as a reference for the Indonesian government to reduce inequality and poverty in the country by realizing the potential of alms in Indonesia.
Neuroinflammation in Schizophrenia
Authors: Mawey Feytie Magda , Karimah Azimatul , Limoa Erlyn , Nazmuddin Muhammad
Published: June 2021

Schizophrenia is a chronic debilitating mental illness. In many aspects, the neuropathology of schizophrenia is closely associated with neuroinflammation, especially microglial activation. Microglial hyperactivity, which is characterized by the predominant release of proinflammatory cytokines serves as the basis of the neuroinflammation hypothesis in schizophrenia. The enhanced inflammatory induce neuronal susceptibility to oxidative stress and trigger, glutamatergic synaptic dysregulation, especially in the mesolimbic and mesocortical pathways. Many in vitro studies, in vivo animal evidence, post-mortem examinations, neuroimaging evaluations with Positron Emission Tomography (PET), anti-inflammatory and antipsychotic use converge upon the central role of microglial activation and proinflammatory cytokines as common of features schizophrenia.
Sucide Attempt in Acute Psychoic Conditions from Biopsychosicial Management Review
Authors: Sarfa Meilaniwati , Wahyurini Melati , Prasetya Era Catur
Published: June 2021

Acute psychotic and transient disorders have annually increased, especially in developing countries. The highest prevalence for acute Psychotic disorders is currently in three developing countries, namely Ibadan, Nigeria, and India. Reported the most causes by psychosocial factors and biological factors. Acute and Transient Psychotic disorders have an annual incidence rate of about 3.9% to 9.6% of the 100.000 population. The reported prevalence range from 10% to 50% mostly in the first year. We aim to report a case of Acute and Transient Psychotic Disorders accompanied by suicide attempts to increase cases so that psychiatrists should be able to make a diagnosis quickly and precisely because it is included in the emergency psychiatric. Acute and Transient Psychotic Disorders often cause symptoms in the form of acts of self - harm or others, in the form of committing suicide, which is a very important social phenomenon and requires attention not only from a psychiatrist but also the general public. The phenomenon of suicide has spread to almost all parts of the world, both in countries with advanced technology and in developing countries. Integrated management of this case is clinically oriented to a biopsychosocial model that is used as a basic principle in the clinical practice of a doctor in building relationships with patients. In this case, we reported a 24 – year - old male, the first attack, occurring within one week, and accompanied by suicidal thoughts. So it is necessary to take a biopsychosocial approach that aims for comprehensive and sustainable interventions.
The Association between Acne Vulgaris and Stress among Adolescents in Kenjeran, Surabaya
Authors: Ollyvia Zsa Zsa , Febriyana Nining , Damayanti Damayanti , Ardani I Gusti Ayu Indah
Published: June 2021

Background: Acne vulgaris is the main skin disease problem for adolescents. The complication of acne in adolescents is scars left on the face, which affects stress levels. Stress has harmful potential when the conditions exceed the individual's ability to cope. Kenjeran area has a tropical climate and weather which are the factors that cause acne vulgaris. Objective: This research aims to study the association between acne vulgaris severity and stress among adolescents in Kenjeran, Surabaya Methods: This research used non-probability purposive sampling technique and observational analytic method with cross-sectional design. Assessment of the acne severity was carried out by dermatologist using Lehmann’s Grading System and stress levels were assessed using the Perceived Stress Scale questionnaire in 109 adolescent subjects. Results: The highest frequency is women aged 15 years. The dominance is in mild acne severity with moderate stress. It was found that adolescents with acne vulgaris are at risk of experiencing stress even though the analysis of the results using fisher-exact showed that there was no significant association between the acne severity and stress level in adolescents with acne vulgaris (p=0.113). Conclusion: The presence of acne vulgaris puts adolescents at risk of experiencing mild, moderate, or severe stress. It requires attention because can cause adverse effects that affect adolescents into adulthood life.
Clinical Microbiology Perspective of Empyema caused by Streptococcus constellatus in Malignancy Patient: A Case Report
Authors: Sekar Agung Dewi , Sarassari Rosantia , Soedarsono Soedarsono , Kuntaman Kuntaman
Published: June 2021

Introduction: Streptococcus constellatus (SC) is commensal bacteria and belongs to Streptococcus anginosus group (SAG). However, SC causes infections especially in patient with underlying diseases. SC empyema is a clinical case that is described in very few studies, especially in Indonesia.Case: A 45-year-old man was admitted to emergency department in Dr. Soetomo General Hospital Surabaya with respiratory insufficiency on November 11th 2020 after 3 months of non-productive cough and a week of weakness. He was diagnosed with empyema on right hemithorax and received chest tube insertion. SC was isolated from pleural fluid sample after first day of culture on Bactec BD bottle. GeneXpert result of pleural fluid was negative for Mycobacterium tuberculosis (MTB). He completed 10 days of intravenous ampicillin-sulbactam and metronidazole. The CT scan reported solid mass of 4.7x7.4x7.8 cm in posterolateral segment of inferior lobe right lung, right pleural effusion, with adenocarcinoma as biopsy result.Discussion: SC is a normal commensal in respiratory tract, however with the presence of a certain factor such as immunocompromised, colonized SAG directly induces an infection after entering normal sterile sites in the body including pleural fluid.Conclusion: Although infection caused by SC is a rare case, it still should be considered in clinical diagnosis and treatment of related infections, particularly in patients with comorbidities. The prognosis was good with appropriate antibiotics and chest tube insertion.
Pemanfaatan Mendeley Sebagai Manajemen Referensi pada Penulisan Skripsi Mahasiswa Program Studi Perpustakaan dan Sains Informasi Universitas Bengkulu
Authors: Cahnia Zelika Anggun
Published: June 2021

Mendeley adalah aplikasi manajemen referensi yang digunakan untuk membantu membuat sitasi dan daftar pustaka pada penulisan karya ilmiah. Penelitian ini membahas tentang Pemanfaatan Mendeley sebagai manajemen referensi pada penulisan skripsi mahasiswa program studi Perpustakaan dan Sains Informasi Universitas Bengkulu. Penelitian ini bertujuan untuk mengetahui bagaimana pemanfaatan Mendeley sebagai manejemen referensi pada penulisan skripsi mahasiswa perpustakaan dan sains informasi. Metode penelitian yang digunakan adalah wawancara dengan pendekatan kualitatif. Subjek penelitian adalah mahasiswa program studi Perpustakaan dan Sains Informasi angkatan 2015 dan 2016. Penentuan informan menggunakan teknik purposive sampling, yaitu pengambilan sampel sumber data dengan pertimbangan tertentu. Hasil dari penelitian ini dapat disimpulkan bahwa pemanfaatan Mendeley sebagai manajemen referensi pada penulisan skripsi mahasiswa program studi Perpustakaan dan Sains Informasi Universitas Bengkulu termanfaatkan.
MARKETINGINFORMATIONEN ALS GRUNDLAGE ZUR VERBESSERUNG VON QUALITÄT DER DIENSTLEISTUNGEN KROATISCHEN REISEBÜROS
Authors: Plantić Diana
Published: June 2021

Ungenügende schriftliche und empirische Materialien können als Ursache schlechter Vertrautheit mit der Tätigkeit kroatischen Reisebüros angesehen werden. Um sich sorgfältig mit der aktuellen Problematik der kroatischen Reisebüros auseinanderzusetzen, der die Reisebüros täglich begegnen, soll man zuerst den aktuellen Stand der Situation und das Konzept ihrer Tätigkeit betrachten, bzw. man sollte die Tatsache beachten, wie stark die Reisebüros moderne Entwicklungsrichtungen akzeptieren und praktizieren. Unter den Bedingungen immer stärker Turbulenz der Märkte der Dienstleistungen, wo man besonders an den Tourismusmarkt denkt, sieht man die Notwendigkeit Anwendung modernen Marketingkonzeptes, in dem man sich auf die Bedürfnisse der Kunden- Touristen konzentriert. Die Reisebüros werden solange auf dem sehr konkurrenzfähigen Markt bleiben, bis sie den Forderungen der Touristenansprüchen entsprechen. Die durchgeführte Forschung weist auf den Mangel und das Nichtbeachten der Marktinformationen hin, die als Ausgangspunkt zur Qualitätsbeförderung der Dienstleistungen kroatischen Reisebüros dienen sollten.
SUSTAINING OR SURVIVING? AN EXPLORATORY CASE STUDY ON COVID-19’S IMPACT TOWARDS HOTEL BUSINESSES
Authors: Bhrammanachote Winayaporn , Sawangdee Yothin
Published: June 2021

Purpose – The aim of this research is to develop a sustainable model for local hospitality businesses in Chiang Mai to mitigate risk during the Covid 19 crisis and become resilient when the situation improves. This research study seeks to explore whether local hospitality businesses in Chiang Mai are taking a sustainable or survival approach in response to the pandemic situation that is occurring worldwide. Design – This is a mixed methods research guided by three research questions to support the aim of the study. Methodology – Five hotels in the province Chiang Mai were selected for the survey and the results were subjected to data triangulation to obtain ideas for a sustainable model. The 400 questionnaires were distributed to 85 hotels including 8 hotels rated 5 stars, 47 hotels rated 4 stars and 30 hotels rated 3 stars in the province Chiang Mai. Approach –Data triangulation was used to test the three questions to ensure the validity of the study: the results of research question number one were compared separately with the results of research question number two and number three; the results of research question number two were compared with the results of research question number three. Findings –Hotels can be viable in the long run if the government creates environmental conditions that support a healthy and intelligent organization to take proactive measures to take care of the welfare of the employees and residents. The overall survival adjustment in the COVID -19 pandemic critical conditions of hotels in the province Chiang Mai was high at 3.96. The correlation coefficient of the cause variables was market adjustment (X1), sustainability adjustment (X2) and learning adjustment (X3) have a positive correlation with the survival of hotels in the province Chiang Mai during the pandemic COVID -19. The survival of hotels in the province Chiang Mai amid the COVID -19 pandemic can be predicted by the underlying event such as learning adjustment (X3) and marketing adjustment (X1), which has an accuracy of 52.70 % and statistical significance at the 0.01 level. Originality of Research – The paper captures the current situation of how Covid-19 has caused a major disruption to hotel businesses in Chiang Mai, Thailand.
Solid-State Hydrogen Storage: Materials, Systems and the Relevance of a Gender Perspective
Authors: Dematteis Erika Michela , Barale Jussara , Corno Marta , Sciullo Alessandro , Baricco Marcello , Rizzi Paola
Published: June 2021

This paper aims at addressing the exploitation of solid-state carriers for hydrogen storage, with attention paid both to the technical aspects, through a wide review of the available integrated systems, and to the social aspects, through a preliminary overview of the connected impacts from a gender perspective. As for the technical perspective, carriers to be used for solid-state hydrogen storage for various applications can be classified into two classes: metal and complex hydrides. Related crystal structures and corresponding hydrogen sorption properties are reviewed and discussed. Fundamentals of thermodynamics of hydrogen sorption evidences the key role of the enthalpy of reaction, which determines the operating conditions (i.e. temperatures and pressures). In addition, it rules the heat to be removed from the tank during hydrogen absorption and to be delivered to the tank during hydrogen desorption. Suitable values for the enthalpy of hydrogen sorption reaction for operating conditions close to ambient (i.e. room temperature and 1-10 bar of hydrogen) are close to 30 kJ·molH2 1. The kinetics of hydrogen sorption reaction is strongly related to the microstructure and to the morphology (i.e. loose powder or pellets) of the carriers. Usually, kinetics of hydrogen sorption reaction is rather fast, and the thermal management of the tank is the rate determining step of the processes. As for the social perspective, various scenarios for the applications in different socio-economic contexts of solid-state hydrogen storage technologies are described. As it occurs with the exploitation of other renewables innovative technologies, a wide consideration of the social factors connected to these processes is needed to assess the extent to which a specific innovation might produce positive or negative impacts in the recipient socio-economic system and to explore the potential role of the social components and dynamics in fostering the diffusion of the innovation itself. Attention has been addressed to the gender perspective, in view of the enhancement of hydrogen-related energy storage systems, intended both in terms of the role of women in triggering the exploitation of hydrogen-based storage as well as to the impact of this innovation in their current conditions, at work and in daily life.
Geometrical transformations and development of geometry
Authors: Giménez Joaquin , Thaqi Xhevdet , Vanegas Yuly
Published: June 2021

A way of systematizing different geometries by geometrical transformations is presented by using Klein’s perspective. Symmetry is considered the basic precedent, and different groups of transformations are introduced by using Erlangen program ideas. So, to focus on the importance of geometric transformations, two purposes are shown: first, the classification of geometries is based on the invariants of geometric transformations; and second, the construction of geometry unlike the theory of deduction can be done by means of geometric transformations.
Oxidation State analysis of LiFeSixP1-xO4/C (x = 0.06) with X-ray Absorption Near Edge Structure (XANES) in Fe K-edge and Si K-edge
Authors: Intifadhah Sahara Hamas , Maghfirohtuzzoimah Vera Laviara , Az-zahra Pelangi , Klysubun Wantana , Astuti Fahmi , Zainuri Mochamad , Darminto Darminto
Published: June 2021

The development of LiFePO4 as a cathode materials on lithium-ion battery was increased with the use of additional techniques such as atomic doping and coating. The material used in this report was LiFeSi0.06P0.94O4/C (LFP Si-6%), synthesized with doping silicon 6% and 11wt% carbon coating by a solid state method. X-ray Absorption Spectroscopy (XAS) characterization was used to investigate the effect on electronic and atomic structure of LFP Si-6%, especially in X-ray Absorption Near Edge Strucuture (XANES) region. XANES data measured on Fe K-edge and Si K-edge. Fe foil, FeO, Fe2O3, FePO4, Si powder, SiO, SiO2 were used as a standard sample for comparison with the result of LFP Si-6%. XANES analysis showed that the energy absorption of Fe K-edge and Si K-edge in LFP Si-6% was 7124.94 eV and 1846.16 eV, respectively. The oxidation state of Fe was Fe2.576+ between Fe2+ and Fe3+, while Si was close to the estimation of Si4+. In addition, the linear combination fitting (LCF) in XANES Fe K-edge was performed to show the ratio of Fe2+/Fe3+ (FeO/Fe2O3).
The Influence of AC Driving Current on Magnetoimpedance in [Ni80Fe20/Cu]x/Cu/[Ni80Fe20/Cu]6-x Multilayers
Authors: Rusydan Dian Afif , Ismail Ismail , Sutomo Artono Dwijo , Utari Utari , Purnama Budi
Published: June 2021

The phenomenon of magnetoimpedance in the multilayer configuration of [Ni80Fe20/Cu]x/Cu/[Ni80Fe20/Cu]6-x with x = 1, 2, and 3 has been successfully investigated. The electrodeposition method used for the multilayer film preparation on the meander pattered of Cu PCB. The obtained multilayer samples were evaluated the MI effect at room temperature with a frequency of 100 kHz. Here, the MI effects were evaluated for a variation of the AC driving current i.e. IAC = 4 mA, 8 mA, 12 mA, 16 mA, and 20 mA. The MI measurement results show that the multilayer x = 3 has the largest MI ratio and the multilayer with x = 1 was the smallest one. It is indicated that interlayer coupling contributes to the MI effect.  Whereas the skin depth also confirms to contribute the MI ratio that showed the MI ratio increase with the increase of the IAC.
Whatsapp Small Groups sebagai Media Pembelajaran Maharah Al-Kalam di Masa DARING
Authors: Sa`diyah Halimatus , Alfian Ivan
Published: June 2021

Arabic learning is carried out online including speaking skills. This condition causes the absence of offline meetings between students and makes it awkward for them to have dialogue in Arabic with their friends. For that, lecturers must be creative so that the target of learning speaking skills can still be achieved. One of them is by using the Whatsapp small groups. This research is descriptive qualitative type.This study aims to describe the Whatsapp small group as a learning media for speaking skills. Respondents in this study were 39 students in the PKPBA (Special Arabic Language Learning Program) class PS7. Data obtained through interviews, observation, and documentation. The results of this study indicate that learning speaking skills online using the Whatsapp small group media can foster comfortable interactions for students so that there is no feeling of awkwardness, shame, or fear of being wrong if they have to dialogue with other students. Also, learning speaking skills is helped using voice note and video call features on the Whatsapp small group media.
Eocene–Oligocene Crustal Thickening-Collapse of the Eastern Tibetan Plateau: Evidence from the Potassic Granitoids in SW China
Authors: Gou Qiyu , Qian Xin , Wang Yuejun , Wang Yang , Zhang Yuzhi , Wang Yukun
Published: June 2021

The eastern Tibetan Plateau is a key part of the eastern India–Asia collisional zone, a region that records multiple overprinting tectonic and magmatic events. This study presents new geochronological, geochemical, and Sr–Nd–Hf–O isotopic data for Cenozoic potassic granitoids in eastern Tibet, southwestern China, which recorded the tectonic evolution of the eastern Tibetan Plateau. These potassic granitoids are formed between 37.6 and 32.9 Ma and are geochemically subdivided into the following: Group 1, adakite-like granites; Group 2, syenites; and Group 3, low-εNdt granitoids. The Group 1 samples are similar to high-silica adakites in that they have variable SiO2 contents (63.31–73.62 wt.%) and high Sr/Y and La/Yb ratios. These samples have εNdt and εHft values that range from −5.8 to −0.6 and from −4.3 to +5.2, respectively, with δ18O values of 6.78‰–7.36‰. The Group 2 samples are syenites, contain 56.36–63.86 wt.% SiO2 and high concentrations of Y and Yb, and have εNdt values from −8.4 to −2.4, εHft values from −6.1 to +1.1, and δ18O values of 6.37‰–6.89‰. The Group 3 samples have a narrow range of SiO2 concentrations (62.27–64.59 wt.%), high Sr/Y and La/Yb ratios, δ18O values of 6.31‰–6.82‰, and low εNdt and εHft values (−12.6 to −10.9 and −11.4 to −6.6, respectively) that are similar to the values obtained for the contemporaneous Yao’an lamprophyres. These data indicate that the Group 1 samples are formed from magmas sourced from a heterogeneous and thickened region of the lower crust containing an enriched mantle component. Group 2 magmas were most likely derived from contemporaneous mafic melts sourced from an ancient region of the lithospheric mantle previously modified by the incorporation of recycled components. The Group 3 samples have distinct Sr–Nd–Hf isotopic compositions that are indicative of derivation from magmas generated by the fractional crystallization of lower crustal melts sourced from ancient enriched mantle of the Yangtze Block. Combining these new data with the results of previous research suggests that the Cenozoic potassic igneous rocks of eastern Tibet were formed as a result of the thinning of the lithospheric mantle and an associated crustal collapse event, potentially representing a regional late Eocene to early Oligocene transition from compression to transtension in the eastern Tibetan Plateau. These potassic igneous rocks are contemporaneous with or are younger than igneous rocks in the Qiangtang Block, suggesting that the magmatic response to the India–Asia collisional event was initiated in the central Tibetan Plateau before propagating towards the eastern margin of this region.
Use of Particulate Diverter During Acid Treatments Progress in Carbonate Assets in Northern Region of Mexico
Authors: Medina Eber , Flores Alejandro , Campos Katya
Published: June 2021

Enhancing stimulation treatments in carbonate reservoirs is a continuous process that includes input from previous operations and production results. Individually, stimulation provides an opportunity to improve the treatment design by means of various factors, such as changes to rates and volumes, new fluid designs, use of nitrogen to increase energy and recover additional fluid after the operation, changes to the well completion, novel diversion techniques, and additional additives. These factors affect overall optimization of fluid distribution. This paper discusses the use of particulate diverter systems during acidizing treatments and highlights how such treatments have progressed. A case study of a carbonate formation in northern Mexico is also presented.

A carbonate field in northern Mexico was analyzed in 2010 to implement a stimulation treatment. The operations ranged initially from reactive and nonreactive stimulation treatments at low-pumping rates to hydraulic acid fracturing in a single formation. After understanding the use of hydraulic acid fracturing in a single zone, multiple formation zones were fractured to improve production while introducing changes in the well completion to enable a faster operation. Multiple acid fracturing treatments during a single intervention were performed with a particulate diversion material to increase the zonal coverage. The successful diversion application has been documented using diagnostics, such as temperature profiles and radioactive tracers.

When a reactive and nonreactive stimulation treatment was performed, the average production in the field was 30 BOPD. Later, with the implementation of hydraulic acid fracturing in a single interval (more than 20 fracturing operations), the average production per well increased to 100 BOPD. More recently, in the last 15 wells, the application of fracturing improvements and the stimulation of two to three zones using particulate diversion to distribute the fluid achieved average production results of approximately 300 BOPD. These results represent a threefold increase since the initial fracturing operations and a tenfold increase since stimulation operations began in the field.

Improvements in acid diversion techniques using particulate diverters has provided significant advantages by enabling effective treatment of several zones in one step, without stopping the operation. This paper describes the design and implementation of the diverting system used during the case study to improve production in a carbonate formation.
Investigation of Reduced Interfacial Tension by Surfactant Flooding in Mixed-Wet Reservoirs
Authors: Aslam Usman
Published: June 2021

Surfactant flooding has long been considered a reliable solution for enhanced oil recovery, either by reducing oil-water interfacial tension (IFT) or through wettability alteration. This paper reveals the effect that reduced IFT has on capillary trapping in heterogeneous reservoirs. This effect is investigated through various numerical experiments on different simulation models where rock capillary pressure is assumed to scale with IFT. Capillary contrast on the scale of a few centimeters to a few tens of meters is reduced in the presence of surfactants. This reduction in IFT, under very specific circumstances, creates favorable conditions for increased or accelerated hydrocarbon production from mixed-wet reservoirs. The focus of this study is to ascertain the effectiveness of surfactant flooding in mixed-wet reservoirs.

Simulation studies of different mechanisms which are believed to occur in mixed-wet reservoirs are presented. Simulation results indicate the promising effect of surfactant flooding on oil recovery, depending on the type of reservoir. Detailed fine-scale simulation studies are carried out with representative relative permeability and imbibition capillary pressure curves from mixed-wet cores. By designing and selecting a series of surfactants to lower the IFT to the range of 10-3dynes/cm, a recovery of 10 to 20% of the original oil-in-place is technically and economically feasible.

The efficiency of surfactant flooding is investigated through sensitivity scenarios on formation rock/fluid parameters, including permeability, interfacial tension, rate flow, etc. Geological heterogeneity (layering and heterogeneous inclusions), imbibition capillary pressure curves, viscous/capillary balance (Nc), and gravitational forces were all found to have an impact on recovery by surfactant flooding. Numerical model dimensions, permeability, IFT, density contrast between oil and water, and injection flow rates were found to be the critical parameters influencing simulation results.

Gravity segregation, typically ignored in earlier studies, was found to have a significant effect on reservoir performance. Two different numerical models, with and without impermeable shale streaks, were used to capture the gravity segregation effect. The results revealed that the reduction in interfacial tension helps gravity to segregate oil and water, ultimately resulting in improved oil recovery. Moreover, results from the numerical simulation studies revealed that either an inexpensive or a good quality surfactant at low concentration can be used to obtain the same enhanced oil recovery. The effect of change in oil relative permeability curvature, due to reduced interfacial tension, also revealed a reduction in the remaining oil saturation with an increase in the capillary number.
Application of an Integrated Ensemble-Based History Matching Approach - An Offshore Field Case Study
Authors: Aslam Usman , Perez Cardenas Luis Hernando , Klimushin Andrey
Published: June 2021

The Internet of Things has popularized the notion of a digital twin - a virtual representation of a physical system. There are substantial risks associated with designing a development plan for an oilfield and the industry has been making use of reservoir models - digital twins - to improve the decision-making process for many years. With an increase in the availability of computational resources, the industry is moving towards ensemble-based workflows to estimate risk in field development plans. In this paper, we demonstrate the use of an integrated ensemble-based approach to assess uncertainties in the reservoir models and quantify their impact on the decision-making process.

An important feature of a digital twin is its ability to use sensor data to update the virtual model, more commonly known as history matching or data assimilation. We demonstrate how production data can be used to identify and constrain the uncertainties in the reservoir model. Production data is incorporated using Bayesian statistics and state-of-the-art supervised machine learning techniques to create an ensemble of models that capture the range of uncertainties in the reservoir model. This ensemble of calibrated models with an improved predictive ability provides a realistic assessment of the uncertainty associated with production forecasts.

The ensemble-based approach is demonstrated through its application on an offshore oilfield located in the North Sea. The field is highly compartmentalized and has high structural uncertainty following the interpretation and depth conversion. An integrated cross-domain model is set up to incorporate typically ignored structural uncertainty in addition to the uncertainties and their dependencies in the dynamic parameters, including fault transmissibility, pore-volume, fluid contacts, saturation, and relative permeability endpoints, etc. Results from the history matched ensemble of models show a significa nt reduction in uncertainty in these parameters and the predicted production.

An advantage of the proposed technique is that the automated, repeatable, and auditable ensemble-based workflow can assimilate the newly acquired measured data into the reservoir model at any time, keeping the model up-to-date and evergreen.
Carbon Dioxide Sequestration and Drainage in Saline Aquifer
Authors: Ennin Edward
Published: June 2021

Geological storage of CO2 in saline aquifers is recognized as a favorable technique that could deliver a significant decrease in CO2 emissions over the short to medium-term. However, the major risk is the possibility of leakage and injection limitation due to pore pressure. This research investigates the three major mechanisms of CO2 trapping to determine which method safely captures the most CO2, interrogates the pore pressure effect on storage, and compares traditional core flooding methods for CO2 storage with CO2 drainage which is more practical in the aquifer.

A core flooding set up was built to replicate reservoir conditions of the Anadarko Basin in Texas, USA. The research involved three reservoir pay zone rocks obtained from depths of about 7687ft that were pieced together to undergo core flooding at 4400psi-5200psi and a temperature of 168°F. In the first study conducted the core was flooded with supercritical CO2 and brine of salinity 4000ppm to generate relative permeability curves to represent drainage and imbibition. For the duration of the 3rd, 4th, and 5th studies the core saturated with brine is flooded with CO2 at pressures of 4400psi, 4800psi, and 5200psi. Parameters like the volume of CO2 captured, connate water volumes, differential pressure, Ph of produced water, trapping efficiency, relative permeability, and fractional flow curves are noted.

After scrutinizing the result it is observed that the highest volume of CO2 is captured by solubility trapping followed by structural trapping and residual trapping in that order. From this research, it can be concluded that CO2 trapping, at least for these reservoir rocks, is not affected by pore pressure. Also contrary to most practices CO2 storage is best replaced in the laboratory using drainage experiments instead of the widely used relative permeability approach.
Experimental Separation Performance of In-Line Piggable Liquid Removal Unit – Pseudo Dry Gas Systems
Authors: Liebana Laura , Thomas Lee , Wood Terry , Lao Liyun , Rogerson Graeme
Published: June 2021

Pseudo Dry Gas (PDG) technology is proposed as an alternative concept for transporting multiphase fluids (gas, condensate and water) for long deep-water subsea tieback developments (Ref 1 - OTC-28949-MS) (Ref 2 - IPTC-19440-MS). Using PDG technology, subsea pipeline networks can be extended to excess of 200 km total length and considerably reduce the backpressure on the wells. This allows improved recovery of the reserves and the ability to reach currently stranded fields, especially deep-water lower-pressure gas fields.

The basis of the PDG system is to remove the liquid of the main pipeline system using Piggable Liquid Removal Units. With the removal of the liquid, the gravitational pressure losses in the system are eliminated allowing the pipeline to operate like a "Pseudo" Dry Gas system. The liquid phase is transported back to shore using a second smaller pipeline running in parallel to the main pipeline by means of subsea liquid pumps (Ref 3 - OTC-29332-MS).

After techno-economic reports were completed for a known basin of stranded gas in the West of Shetland, an Oil and Gas Technology Centre (OGTC) experimental project was established to determine the operation performance of the element within the PDG technology with lowest Technology Readiness Level (TRL). Currently the liquid removal unit has a TRL2 and a TRL4 will be achieved after the experimental testing programme has been fully completed. This paper assesses the separation performance (Efficiency) of the Piggable Liquid Units or PDG unit. Previous Flow Assurance and Computational Fluid Dynamics (CFD) established expected efficiencies between 84-99% depending on the gas and liquid flow rates and other factors such as unit orientation, liquid type, operating pressure and temperature.

Each PDG unit has two modules which allow for gas-liquid separation of the multiphase fluid in the pipeline. A PDG unit prototype has been built and a testing programme has been developed and undertaken in collaboration with Cranfield University (CU) using the large scale Inclinable Multip hase Flow Loop facilities. The testing programme has two test matrices: Matrix 1 which studies the performance of a single module of the PDG unit and Matrix 2 which investigates the efficienc y of the entire PDG unit (two separation modules). Matrix 1 of the testing programme allows to characterise the system varying the flow conditions (flow regime, liquid and gas flow rates), drop out liquid level and size, effect of sand and the inclination and orientation of the unit as would be expected once installed. This paper focuses on the results obtained from Matrix 1 testing programme and compares them with the initia l PDG unit estimated efficiency values used in previous studies to demonstrate the prove of concept of the PDG technology. The overall conclusion is that the performance of the PDG liquid removal unit is greater than the ones originally used in technology assessment reports.