bluuebunny/crossref_metadata_2025 huggingface dataset:
Dimensión de competitividad urbana en la zona sur de Tamaulipas: el papel del gerente
Authors: Chávez Meléndez Javier
Published: June 2021

El Banco Interamericano de Desarrollo (BID) desarrolló una metodología basada en una serie de indicadores denominada ICES (iniciativa de ciudades emergentes sustentables), que como primera etapa propone el diagnóstico de una ciudad o zona conurbada para poder planear las acciones futuras de mejora (BID, 2014). Este proyecto de investigación se sustentó en este modelo y en el modelo del IMCO. Para lo cual, se desarrolló una investigación descriptiva, con enfoque cuantitativo basada en el desarrollo de la dimensión de competitividad urbana en la zona sur de Tamaulipas. Los resultados obtenidos se presentan y permiten generar un espacio de acciones de planeación, reflexión y de formulación de políticas públicas.
The Resource-Based View and The Concept of Value: The Role of Emergence in Value Creation
Authors: Luján Salazar Luis Armando
Published: June 2021

This theoretical paper deals with the concept of value. It asserts that value is the only and necessary condition in the resource-based view (RBV). It also argues that no resource or strategy is valuable per se: it is related to a configuration of resources, routines, and embedded assets. For example, concerning the RBV attribute of imitation, we can ask to what extent a valuable resource is independent of the rest of resources, and by extension, to what extent a configuration of resources is rare by itself. This paper discusses the emergence of value and it is embeddedness in a configuration of resources. Revising the concept of value could challenge the other main conditions in the RBV: rarity and cost of imitation, impossibility to replace with strategic substitutes. If the relations of these attributes with the rest of the resources are taken into account, we might have a better understanding of how value emerges and how a firm’s resources and capabilities are related with the creation of value.
Evolución de la periferia europea en la cadena de valor automotriz: lecciones aprendidas de Galicia (España)
Authors: Lampón Jesús F. , Cabanelas Lorenzo Pablo
Published: June 2021

La industria automotriz llegó hace casi 60 años a Galicia de la mano de la empresa francesa Peugeot-Citroën. En este lapso de tiempo se han producido cambios en el sistema productivo que ha permitido una evolución hacia actividades de mayor valor añadido. La disponibilidad de un tejido institucional sólido, la alta cualificación del empleo y el desarrollo de un entramado productivo con base local, han sido algunos de los factores clave en esta evolución. Las lecciones obtenidas pueden constituir una referencia para otras regiones periféricas del sector automotriz. Sin embargo, la industria de la región vislumbra una serie de retos que tendrá que acometer y que serán extensibles a otras regiones. Estos retos exigen un enfoque que integre al tejido productivo, las administraciones públicas y la sociedad.
Reseña de Sánchez, José (Coord.) Competitiveness for Industry, Science and Education. México: Universidad de Guadalajara. 2016, 264 pp.
Authors: Ruiz Campos Sofía
Published: June 2021

Esta obra integra doce capítulos que pretenden analizar los factores determinantes de la competitividad. En ellos existe la tendencia a relacionar la investigación científica, así como, la transferencia tecnológica con la gestión del conocimiento en la empresa. Para la mayor parte de los autores implicados en el presente libro la industria, la ciencia y la educación forman el vórtice de la competitividad.
Factores condicionantes del análisis financiero en una empresa
Authors: Gaytán Cortés Juan
Published: June 2021

Los factores condicionantes tanto internos como externos que son necesarios estudiar y tomar en cuenta a la hora de realizar un análisis financiero completo de la situación de una empresa se clasifican y dividen en los siguientes grupos: a) factores macroeconómicos, b) microeconómicos, c) operativos y d) gestión financiera
Carta del editor
Authors: González Alvarado Tania Elena
Published: June 2021

El equipo editorial de la Revista Mercados y Negocios ha estado realizando cambios significativos en el último año, a fin de que la revista alcance una mayor visibilidad en paralelo a mayor calidad en sus contenidos. Esto último impone un doble desafío. El reto principal es mantener la calidad en el arbitraje y contenidos, al mismo tiempo que cubrir con los tiempos para publicar puntualmente. Reconociendo ante cualquier obstáculo o dificultad que el elemento clave es el proceso de arbitraje
Talento humano: una contribución a la competitividad organizacional
Authors: Chávez Jiménez Enore Adriana , Vizcaíno Antonio de Jesús
Published: June 2021

El objetivo del artículo es identificar la relación que existe entre el talento humano y la competitividad de las organizaciones, como parte a la revisión documental obtenida en los antecedentes científicos del estudio y sustentado en la teoría de recursos y capacidades. Producto de esta revisión, se encontró que las personas constituyen un recurso valioso dentro de la organización y la formación del talento humano es una variable determinante para lograr la competitividad de las organizaciones.
Determinantes y modelos para medir el desempeño de una cadena de suministro agroalimentaria: una revisión de la literatura
Authors: Gutierrez Ortiz Ariel , Infante Jiménez Zoe Tamar
Published: June 2021

El propósito de esta investigación es identificar, a través de una revisión de la literatura, los factores determinantes y modelos que se utilizan con mayor frecuencia para medir el desempeño de la cadena de suministro agroalimentaria. A través de un método documental-exploratorio, en diversos trabajos de investigación, se logró identificar que la eficiencia, la capacidad de respuesta, la flexibilidad, la calidad del alimento y la calidad en el proceso, y los modelos determinísticos y de negocios son los que con frecuencia se utilizan para medir el desempeño de una cadena de suministro.
Emprendimiento e innovación como detonadores de negocios competitivos en el mercado de servicios
Authors: Rivas Aragón Bitia Betsaida , Cruz Reyes María Angélica , Meléndez Flores Rebeca
Published: June 2021

El objetivo del trabajo es determinar la viabilidad del negocio de servicios, al evaluar dos de las etapas de un plan de negocios. Para ello, primero se conformó el marco teórico que incluye el emprendimiento y el plan de negocio, después se analizó el proceso de la mercadotecnia y el económico-financiero, mediante la entrevista se identificó el perfil de la emprendedora, se aplicó un cuestionario para determinar las variables para la viabilidad de negocio y financiero. Entre los hallazgos encontrados está la viabilidad de mercado, pero no la económica financiera.
أحاديث الترغيب والترهيب في وحدة الأمة: دراسة تحليلية
Authors: Hoque Mesbahul , Abdul Halim Amran , Ali Abdul Rab Muneer , Azmi Ahmad Sanusi
Published: June 2021

There are a lot of hadith were narrated from the Prophet (S.A) that emphasize the factors of the unity of the Ummah and desire it and warn strongly about the separation and fragmentation in the Ummah. This paper aims to study and analyze some of those hadiths, by using descriptive and analytical approach. Result of this study shows that the Messengers of Allah was very concern for the unity of Ummah as his concern for Iman, Out of his concern for the unity of Ummah he established the pillars of unity in the Ummah, and chose a policy of enticement and intimidation towards those who separate the Ummah and disperse its unity.
STUDENTS’ AND STUDENT TEACHERS’ SENSE OF BELONGING TO SCIENCE: WHAT DO WE KNOW SO FAR?
Authors: Feser Markus Sebastian
Published: June 2021

Forming a sense of belonging to others is a fundamental need of humans as social beings (Baumeister & Leary, 1995). Meeting this fundamental need crucially influences individuals’ intrinsic motivation (Ryan & Deci, 2000) and identity development (Wenger, 1999). Given this, a growing number of studies have investigated the extent to which university students’ success and wellbeing in science education is related to their sense of belonging to science. This research has brought greater clarity to university students’ development in science education; however, numerous aspects of university students’ sense of belonging to science remain understudied. In particular, there has been insufficient research on how sense of belonging to science might moderate or influence initial science teacher education. Therefore, this editorial aims to provide an overview of the major research findings that address students’ and student teachers’ sense of belonging to science and to inspire future research in science (teacher) education.
A SYSTEMATIC REVIEW OF THE RESEARCH PAPERS ON CHEMISTRY-FOCUSED SOCIO-SCIENTIFIC ISSUES
Authors: Çalık Muammer , Wiyarsi Antuni
Published: June 2021

Although chemistry-focused socio-scientific issues support the ‘relevance’ model of chemistry education, the related literature has lacked any systematic review handling them together. For this reason, this research aimed to thematically synthesize the research papers on chemistry-focused socio scientific issues (SSI) from 2008 to 2020 and inferentially evaluate them in terms of the relevance model of chemistry education. After searching international and national well-known databases through relevant keyword patterns (e.g., Pattern 1: socio-scientific issues and chemistry education), 65 research papers were apparent for the systematic review. Then, the authors generated primary and secondary codes for the research papers and then inferentially marked their ‘relevance’ components. The systematic review indicated variation of research areas (e.g., relevance model of chemistry education) and dominant research foci for different themes (e.g., competencies and related variables for the theme ‘aims’; pollution, energy, industry and fabrication-based problems for the theme ‘SSI’; organic compounds for the theme ‘chemistry concepts’). Further, it revealed that the research papers on chemistry-focused SSI had some shortcomings at handling all components of the relevance model in a balanced way. The current research suggests professionally training teachers about how to integrate chemistry-focused SSI and the relevance model into school chemistry.
Keywords: chemistry education, relevance model, socio-scientific issues, systematic review
ENVIRONMENTAL AWARENESS, ATTITUDES, AND BEHAVIOUR OF PRESERVICE PRESCHOOL AND PRIMARY SCHOOL TEACHERS
Authors: Dolenc Orbanić Nataša , Kovač Nives
Published: June 2021

Environmental education represents an important factor in solving environmental issues and teachers have an important role in developing the environmental literacy of future generations. The aim of the present research was to assess and compare preservice preschool and primary school teachers’ environmental awareness, attitudes, and behaviour, as well as their opinions about environmental education. The research was carried out with 152 Slovenian preservice teachers of the Faculty of Education, University of Primorska. The data were collected using a questionnaire. Results showed that students have a relatively high level of environmental awareness and mostly demonstrated a positive attitude towards nature and its protection. Students highlighted the importance of environmental education in early childhood. The research showed no significant differences in the responses of students of both programmes in general, which indicates that the course contents have a less significant influence on students’ awareness, behaviour, and attitudes. According to the findings, there is a need for an improved course within the teacher training programme, especially with the implementation of more innovative teaching methods and activities to increase students’ environmental literacy. Keywords: environmental attitudes, environmental behaviour, environmental awareness, preschool education, primary school education, university students
BIBLIOMETRIC ANALYSIS OF THE INTERNATIONAL SCIENTIFIC PRODUCTION ON ENVIRONMENTAL EDUCATION
Authors: Lopera-Perez Marisol , Maz-Machado Alexander , Madrid María José , Cuida Astrid
Published: June 2021

Environmental Education has become over recent decades an emerging area of knowledge; its evolution has been conditioned not only by different regional dynamics, but also by international guidelines and trends. Therefore, the literature reports multiple and diverse pedagogical, curricular and transdisciplinary approaches to this topic. Likewise, studies on the dynamics and trends in the generation and production of knowledge are relevant to both teachers and researchers in every field of knowledge. In this sense, it is presented a bibliometric study that aims to analyse the international scientific production on Environmental Education on the Web of Science (WoS) within the categories Education and Educational Research and Education, Scientific Disciplines for the last two decades (2000-2019). The information obtained was analysed using different bibliometric techniques, like descriptive statistics, degree of collaboration and co-occurrence maps generated by VOSviewer (version 1.6.15) software. The results show the accelerated increase in the production of knowledge in this area, they present the main research contexts, as well as some educational and research perspectives. Also, the collaboration between authors and universities was identified.
Keywords: bibliometrics analysis, environmental education, scientific education, scientific production
EXPLORING IN-SERVICE SCIENCE TEACHERS’ BELIEFS ABOUT GOALS OR PURPOSES OF SCIENCE TEACHING
Authors: Maseko Bob , Khoza Hlologelo Climant
Published: June 2021

Research indicates that teachers’ beliefs about goals or purposes of science teaching, as one dimension of science teaching orientations, influence what happens in the classroom. The purpose of this research was to explore the self-reported and enacted goals or purposes of science teaching of four in-service Malawian science teachers using the curriculum emphases concept as a theoretical lens. This research used qualitative case study research design. Semi-structured interviews and classroom observations were used to explore teachers’ self-reported and enacted goals or purpose of science teaching, respectively. A deductive analysis approach was used to analyze interview and classroom observation transcripts, to understand the teacher’s goals or purposes. Results reveal that while teachers have multiple self-reported goals or purpose of science teaching, most of these are not enacted during teaching in the classrooms. This suggests the topic-specific nature of the goals or purposes. Results also show that all the teachers were not aware of the self-as-explainer goal or purpose of science teaching both during interviews and instruction. These findings are discussed, and implications are proposed for science in-service teacher professional development and pre-service teachers’ training programs.
Keywords: science teachers’ beliefs, curriculum emphasis, goals or purposes, science teaching orientations, teacher professional knowledge
EDUCATIONAL EFFICIENCY AND STUDENTS’ INVOLVEMENT OF TEACHING APPROACH BASED ON GAME-BASED STUDENT RESPONSE SYSTEM
Authors: Radulović Branka
Published: June 2021

Modern approaches in Physics classes which involve the game-based student response system (GSRS) have been in use for a while, but their educational efficiency and students’ involvement have not been examined. Therefore, this research’s main aim was to determine the educational efficiency and students’ involvement of GSRS and to assess their effect on scientific reasoning. The values of educational efficiency and students’ involvement were calculated based on students’ achievement and perceived mental effort. To determine these values, a pedagogical experiment with parallel groups was applied. The research was conducted on a sample of 172 secondary school students, and included material related to direct currents. The results point to positive and higher values of the educational efficiency and students’ involvement for GSRS approach than the conventional approach. It means that GSRS approach causes lower mental effort, letting more space generate in the working memory to perceive and process new information. The results also show a positive effect of GSRS on higher students’ engagement during the class and scientific reasoning. The obtained results undoubtedly indicate the positive effect of GSRS on the students’ performance. Therefore, GSRS approach should be used often in the classroom.
Keywords: educational efficiency, students’ involvement, GSRS, scientific reasoning, teaching physics
THE ALIGNMENT BETWEEN THIRD-GRADE PRIMARY SCHOOL SCIENCE TEXTBOOKS AND CURRICULUM STANDARDS IN CHINA AND JAPAN
Authors: Sun Lihui , Li Liangbo
Published: June 2021

This study applied the Porter’s alignment model to construct a localized two-dimensional framework based on Anderson's taxonomy. The research chose the third-grade primary school science textbooks from two representative presses in China and Japan, coded the textbooks and curriculum standards, calculated the alignment level between the textbooks of the two presses and their corresponding curriculum standards, and discussed the alignment level from the topic, cognitive demand, and emphasis. The results show that the B version in Japan is significantly aligned with the Japanese curriculum standard, but the A version in China does not have significant alignment with the Chinese curriculum standard. Besides, a common problem is that the ratios of life science in sample science textbooks both exceed the requirements of the curriculum standards, and the problems of exceeding the standard in cognitive demand and not highlighting the key points also need to be concerned. This study provides ideas and references for countries with similar educational situations to study the compilation of science textbooks and fills up the deficiency of the international comparison of the alignment between primary school science textbooks and curriculum standards by using the alignment model.
Keywords: alignment evaluation, content analysis, curriculum standards, primary school, science textbooks
La gestión por competencias en la formación de emprendedores de negocios sostenibles. Un análisis desde la academia
Authors: Fonseca Vasconez José Fabián , Andrade Álvarez Carmita Efigenia , Tobar Ruiz María Gabriela
Published: June 2021

Introducción, La globalización ha eliminado las fronteras comerciales dando lugar a que prepondere la competencia, provocando que los más fuertes resisten a las presiones del mercado y los débiles estén destinados a la quiebra e incluso ha provocado que algunos negocios queden solo en su fase de incubación Objetivo identificar las competencias en la formación de emprendedores de negocios sostenible, el cual constituye un tema recurrente en la actualidad, donde la formación del capital humano requiere transformaciones cada vez más competitiva, con un nivel de conocimientos y actitudes con mayor influencia en el conocimiento de la ciencia, la tecnología y la innovación, y la formación de valores éticos que influyan de manera decisiva en el desarrollo de los países Metodología, este estudio considera los métodos empíricos y no empíricos de la investigación porque se fundamentó en analizar las aptitudes y actitudes del talento humano para emprender en un territorio a partir de su estructura, infraestructura y superestructura Resultado, el perfil del emprendedor queda conformado por siete competencias fundamentales para mantener una gestión técnica que asegure los niveles de aportes financieros para fomentar desarrollo sostenible, Conclusiones, se requiere contar con profesionales que logren esta formación con mayor calidad y esto demanda de nuevas estrategias para su desarrollo desde las entidades laborales, y de todo el personal técnico administrativo que coadyuve a un mejor desempeño de su actividad. Actualmente las organizaciones tienden a determinar, atendiendo a su entorno y su estrategia organizacional, cuáles son las competencias que realmente producen un rendimiento superior.
Implementación de la estrategia ambiental Producción más Limpia (PmL) para el proceso productivo de la microempresa Productos Lácteos del Norte
Authors: Nuñez Moreno María Soledad
Published: June 2021

El presente artículo tiene por objetivo implementar la estrategia ambiental Producción más Limpia (PmL) en el proceso productivo de la microempresa Productos Lácteos del Norte, mediante la aplicación de esta estrategia de gestión eficiente, para obtener un ahorro económico y minimizar el impacto ambiental en beneficio de la sostenibilidad industrial. En el artículo inicialmente se realiza una breve revisión literaria de PmL, su importancia, beneficios y marco legal. Posteriormente, se crearon 4 fases para implementar la estrategia, estas fases fueron estructuradas en base a la Guía de Aplicación de PmL en el sector Lacteo del CPML de Nicaragua y la Guía Técnica General de PmL del CPTS de Bolivia. Finalmente, se implementó la estrategia ambiental PmL en la microempresa, mediante el desarrollo de las fases de planeación y organización, re evaluación, evaluación y estudio de factibilidad. En los resultados del estudio de factibilidad se obtuvieron indicadores de consumo de energía de 115,3 W·h/t de queso, que está dentro del valor recomendado; gasto de agua de 9,06 L de agua/kg de leche, que esta fuera del rango permitido. Se implementó la estrategia ambiental PmL en la microempresa, sin embargo, la ejecución del análisis de propuestas a mediano y largo plazo tendrá que ser realizado para su consolidación.
La función sexual y violencia en pareja, en una muestra de mujeres ecuatorianas
Authors: Yerovi Guevara Mélida Karina , Pinos Montenegro Judith Elizabeth
Published: June 2021

Introducción. La violencia de pareja ocurre en cualquier ámbito ya sea este social, económico, cultural, sexual, siendo el ultimo el motivo de la investigación, pues la salud sexual es una parte importante en la calidad de vida y uno de los derechos del ser humano. Esta investigación gira entorno a la pregunta sobre qué parámetros con rasgos anormales se evidencian en las dimensiones de la función sexual en las mujeres víctimas de violencia que asisten a psicoterápica en la Fundación Nosotras Equidad, de la ciudad de Riobamba, de la provincia de Chimborazo. Objetivo. Identificar cambios en la función sexual de quienes atravesaron episodios de la violencia en pareja, en una muestra de mujeres ecuatorianas Metodología. Para ello se optó por un estudio cuantitativo, no experimental, de tipo descriptivo y correlacional, transversal con el uso de dos instrumentos Cuestionario de Cambios en la Función Sexual y Escala de Violencia e Índice de Severidad; en una muestra comprendida por 255 mujeres, cuyas edades son mínimo 18 años y máximo 65 años Resultados. Se evidencia que las afectaciones en la función sexual se correlacionan con la violencia en pareja. Comprobando así la hipótesis de que, a mayor violencia, se presentará los parámetros con rangos anormales en deseo/frecuencia; deseo/interés; placer; activación/excitación y orgasmo. Conclusión. En el estudio, las 255 mujeres viven violencia, en el tejido social de la relación en pareja. La intimidad sexual se ve afectada al presentar disfunciones, manifiesta en la ausencia de interés, deseo, excitación y orgasmo. Los instrumentos aplicados revelan que la función sexual, se asocia con la violencia psicológica y física; siendo la violencia física, en la mayoría de casos de carácter severo; es decir, son mujeres que trascurren su vida con intimidación y alto grado de sufrimiento.
Desarrollo de un sistema de control inteligente basado en redes neuronales aplicado al proceso de pasteurización de lácteos
Authors: Aldaz Vargas Adrián Alejandro , Ocaña Pañora Lando Stephen , Arias Guadalupe Janeth Ileana , Campos Castelo Jonatahn Paúl
Published: June 2021

El proceso de pasteurización requiere la incorporación de tecnología en sus métodos de pasteurización con el fin de mejorar su producción. El objetivo de este sistema es implantar un proceso de pasteurización de una planta de leche, para esto se utilizó la herramienta Matlab 2014 utilizada para el control central del sistema tomando en cuenta las condiciones necesarias del proceso. El control del pasteurizador cuenta con un sensor y sus actuadores cuya función es constante en todo el proceso los cuales envían señales por una tarjeta de adquisición de datos e interpretados en Matlab 2014 y con implementación de una interfaz hombre maquina (HMI) mediante la aplicación Guide. El proceso de pasteurización utiliza inicialmente la leche cruda a temperatura ambiente de 18°C según la norma NORMA NTE INEN 9:2012 (INEN, 2021), será vertida en la marmita evitando su desperdicio, posteriormente se da comienzo al proceso de pasteurizado desde el HMI de Matlab 2014 donde el operador escogerá los parámetros necesarios para su funcionamiento. Para el proceso de pasteurizado se toma en cuenta el método de pasteurización lento y abierto (VAT) el cual consiste en calentar grandes volúmenes de leche en 3 etapas: calentamiento, pasteurización y enfriamiento para finalizar el proceso.
Aplicación de Tecnologías de la Información Geográfica para estimación de áreas afectadas por incendios forestales
Authors: Toaza Patiño Esteban David , Velasteguí Cáceres Julia Desiree , Espinoza Víctor Manuel , Sevilla Hernán Chamorro
Published: June 2021

Introducción. En la actualidad la teledetección es una herramienta que permite obtener información geoespacial de las áreas afectadas por incendios forestales mediante observación sistemática. Objetivo. Aplicar de Tecnologías de la Información Geográfica para la estimación de áreas quemadas desde una perspectiva multitemporal en la provincia de Chimborazo. Metodología. Para determinar la ocurrencia de incendios forestales se utilizó el producto para áreas quemadas de MODIS denominado MCD64A1, que determina áreas quemadas mayores o iguales a 25 hectáreas y su fecha de ocurrencia. La delimitación del área afectada y la severidad de los incendios se realizó mediante los índices espectrales NBR y NDVI (pre y post incendio), calculados con las imágenes utilizadas previamente para la validación área de afectación. El pre y post procesamiento se realizó mediante el programa QGIS 3.4. Resultados. Se determinaron 10 incendios ocurridos en Chimborazo entre los años 2015 al 2018, con un área total de afectación de 2760,59 hectáreas, también se determinó las coberturas afectadas por estos eventos siendo el páramo la que más área de afectación tuvo. Conclusión. La presente investigación demostró que la aplicación de tecnologías geoespaciales son un recurso efectivo y práctico para la gestión de superficies afectadas por incendios forestales ya que los insumos utilizados son de descarga libre y gratuita.
On the possibilities to apply indices of industrial coal-rank classification to determine hazardous characteristics of workable beds
Authors: Antoshchenko Mykola , Tarasov Vadym , Nedbailo Oleksandr , Zakharova Olha , Yevhen Rudniev
Published: June 2021

Purpose is to identify behaviour of the graded indices as well as their correspondence to grades, groups, and subgroups of similar coal metamorphic degrees to determine hazardous characteristics of workable beds while mining. Methods. Rank scale and changes in the graded index values help define the coal grades, groups, and subgroups having comparable characteristics as well as ultimate composition of organic mass. Coal ranking involves the intensified metamorphism manifestation in the process of transition from lignite to black coal, and then to anthracite. Findings. Analysis of the total of the fusainized components has shown that coal grading is within less than 10 and more than 69% range. However, in the majority of cases its values are recommended as those being less than 39 or more than 40% which prevents from determination of reliable correlation relationships. Free heaving ratio is considered together with the plastic layer thickness making it possible to determine quantitively only LF, LS, LC, and L grades. In terms of vitrinite response index, being 0.8-1.4%, LS, LC, and L grades may be considered as coal in the central ranking series. The fact supports available changes in the internal structure. Originality. Behaviour of the graded indices of industrial coal-rank classification has been determined to identify hazardous characteristics of workable beds while mining. Practical implications are the possibilities to improve the regulatory system for safe mining of workable beds while determining differences in characteristics of vitrinite coal and fusainized coal.
Evaluation of exploiting barite, the critical raw material in Slovakia, and benefits of its mining
Authors: Šimková Zuzana , Pavolová Henrieta , Bednárová Lucia
Published: June 2021

Purpose. There are several deposits of critical raw materials in the Slovak Republic, but currently only one is mined. This is a barite deposit in Spiš, which shows an ever-lower volume of exploited raw material year-on-year. However, this area is rich in several confirmed barite veins, which represent potential strategic raw materials. The presented article analyzes in detail and describes the Jaklovce I. deposit, which is located in the Gelnica district in north-east of Slovakia. Despite the fact that Slovakia, as well as most EU countries, is dependent on imports of raw materials, the new deposits represent new potential. Determination of the economic value of these deposits creates a promising potential for the investor, but also, secondarily, a potential for the socio-economic development of regions, as well as for the state. Methods. Based on the evaluation of dynamic economic variables, the article predicts the benefits which mining in this deposit would bring, which are also supported by SWOT analysis of barite exploitation. Findings. According to the methods used during the financial evaluation of the single mined deposit of CRM in Slovakia, which was developed because of CRM criticality in EU, we showed, based on § 14 of the Mining Act no. 44/1988 Coll. the necessity of CRM mining from the view of regions, the state and investors. The present article summarizes impacts of exploiting the barite from Jaklovce I. deposit for the investor, as well as for the state, which is also underlined through SWOT analysis. Originality. This study attempts to point out that mining critical raw materials is economically suitable not only for the state, but also for investors. SWOT analysis also pinpoints most threats, opportunities and some forecasts which should be taken into account while designing the investment project. Practical implications.I nvestment project in mining area is one of the most critical and challenging decisions that experts have to make mainly based on geological, economical and geotechnical properties of the deposit, which are very specific. The same is true for the investment project which represents huge investments and rate of risk
Impact of Artana mine on heavy metal pollution of the Marec river in Kosovo
Authors: Sadiku Milaim , Kadriu Sadija , Kelmendi Mensur , Latifi Letafete
Published: June 2021

Purpose. This paper aims to reflect the extent of the impact of the Artana mine on heavy metal pollution of the waters of the Marec river. Mineralogical pollution of this river resulted in almost total degradation of biota. Methods. To be as realistic as possible in assessing the water quality of the Marec river and of a single spring located in the research area and used for drinking, we have applied the standard methods ISO 5667-6 for surface water and ISO 5667-11 for groundwater. The sampling and the quantity of the samples, as well as their transportation, was done in full compliance with the ISO 5667-1.3 method. Whereas, the conservation of samples taken for the determination of heavy metals is done according to the APHA conservation procedure. For the extraction (mineralization) of heavy metals in the samples taken, the EPA-3015A method was applied, while for the determination of the concentration of heavy metals the SAA (Atomic Absorption Spectrophotometry) measurement technique was applied. Findings. As a result of the industrial activity of the Artana mine, it has been ascertained that the main causes of the pollution of the Marec river waters and the habitat around it is the mineral exploitation activity in this industrial complex. Analysis of water samples discharged from the mine, flotation and drainage of landfills reflect the real state of heavy metals concentration in the Marec river. Originality. In order for the results to realistically reflect the degree of heavy metals concentration in the waters of this river, we have implemented existing and advanced analytical techniques. Practical implications. The water samples from the Marec river were taken and analyzed in January and July 2020. The analysis performed showed significant exceedance of heavy metals concentration in all sampling sites located in the studied industrial area.
Mathematical model to optimize drilling-and-blasting operations in the process of open-pit hard rock mining
Authors: Shcherbakov Petro , Tymchenko Svitlana , Bitimbayev Marat , Sarybayev Nurzhigit , Moldabayev Serik
Published: June 2021

Purpose is to determine a function of the reduced expenditures connected with drilling-and-blasting operations, loading and hauling operations, and rock fragmentation depending upon the cost of machine-shift of the applied facility, its operation modes, hardness of rock being blasted, cost of the used explosive, and rock fragmentation quality based upon the developed optimization mathematical model. Methods. Method of statistical evaluation of natural blockiness structure of the rock as well as quality of its fragmentation by means of explosive energy has been applied. Statistical studies have been carried out concerning the basic indices of rock fragmentation depending upon its largeness and block hardness. Purposely-designed experimental equipment has been applied for sampling analysis of the rock fracturing in the process of its drilling by means of rotary drilling rig. The abovementioned supported representativeness of the sampling. Findings. Statistical distributions of the rock blockiness structure in terms of each bar length involving its place within the drilling assembly as well as in terms of the well depth have been compiled. Visual comparison of experimental data and theoretical data has helped determine that the statistical distributions of natural blockiness structure of the rock have the closest correlation with gamma distribution which differential function has two positive parameters. Statistical dependence has been defined between drilling-and-blasting results and the total expenditures connected with hard rock mining. Originality. A concept of oversize crushing coefficient has been introduced; its statistical dependence upon the mined rock hardness and specific consumption of the applied explosive has been derived. An alternative has been proposed concerning changes in parameters of the differential function of the assumed gamma distribution relative to the predicted granulometric composition of rock mass. Practical implications. Economic and mathematical model has been developed involving a target function of the total expenditures connected with the listed operations as well as a set of constraints avoiding incorrect decisions. The optimization method makes it possible to control drilling-and-blasting parameters at each stage of hard rock mining.
Research on the coupling effect of the composite slope geometrical parameters
Authors: Barvor Yamah Joy , Bacha Sher , Qingxiang Cai , Zhao Chen Shu , Mohammad Nisar , Jiskani Izhar Mithal , Khan Naseer Muhammad
Published: June 2021

Purpose. To analyze the coupling effect between composite slope geometrical parameters. Methods. The slope angle and excavation depth are coupled with load which is waste dump in this case. Several models were created and analyzed to capture their coupling effect and interactions using FLAC/Slope. Findings. When the slope angle and excavation depth are coupled with a load such as that of a waste dump, the factor of safety decreases. But a suitable dumping position can prove vital to enhancing stability. The primary cause of this phenomenon is that the stresses induced by the waste dump decrease as the dump is moved away from the crest of the slope and the stress induced within the zone of active wedge beneath the dump reduces on the reference slip plane. Hence, it can be said that the position of the waste dump in the formation of a composite slope plays a key role in enhancing stability. Factor of safety have the same influence pattern for all parameters induced by stress as that of influence rule. The results obtained from the finite element stress analysis are the same with those obtained for the slope stability analysis. Originality. The current research presents for the first time the coupling effect of the composite slope geometrical parameters and the results of finite element stress analysis, which are similar to those of slope stability analysis. Practical implications. The current research results can be used to effectively analyze and design the composite slopes in soft rocks specially in surface mines.
Determination of the injury probability among coal mine workers
Authors: Nosal Dmytro , Konovalov Serhii , Shevchenko Volodymyr
Published: June 2021

Purpose. Establishing regularities of change in the injury probability and development of a methodology for determining the injury probability of coal mine workers to improve the occupational health and safety (OSH) management system efficiency. Methods. Methods of mathematical statistics and mathematical analysis were used in the data processing of coal mine workers’ injuries; probability theory and risk theory were applied for setting equations to determine the injury probability; correlation and regression analysis were used to determine the density and nature of the dependences reflecting changes in the injury probability. Findings. A calculator has been developed to compute the injury probability of an employee. This instrument distributes the probability into three “zones”: high probability – “red zone”, medium probability – “yellow zone”, and low probability – “green zone”. The injury probability for all employees of the mine administration was calculated. It was found that the clo-sest relationship between the number of injuries and the calculated probability is observed for mining sites (medium probability) and for tunneling sites (high probability). For employees with a calculated high injury probability, in most cases, the causes of injury were objective and less dependent on employees themselves. For employees with a medium probability, the causes independent of and dependent on employees were approximately equally correlated. In the case of employees with a low probability, the main reasons were subjective – dependent on the employees themselves. For employees in the main operational sites (mining and tunneling), the cause of injury is directly related to the specifics of the production operations performed: the presence of loose space. Originality. For the first time, relationships were determined between the injury probability and the profession. We also established relationships between experience at the enterprise, age, marital status of an employee and the injury causes, as well as between the actual number of injuries and the calculated injury probability. Practical implications. A method for determining the injury probability of coal mine workers has been developed and implemented. The ways of improving the methods for calculating the injury probability are determined.
Protecting buried pipelines using different shapes of geofoam blocks
Authors: Hassan Dyaa
Published: June 2021

Purpose. This research presents experimental modeling and numerical analysis on reducing stress and protecting buried pipelines using three arrangements techniques of expanded polystyrene (EPS) geofoam blocks: embankment, EPS block embracing the upper part of the pipe and EPS blocks as two posts and a beam. Methods. An experimental model consisted of steel tank with boundaries dimensions depending on the diameter of the pipe located at the center of it. The backfill on the pipe was made from sand and embedded EPS blocks with two techniques: EPS block embracing the upper part of the pipe and EPS blocks form two posts and a beam. Series of experiments were carried out using static loading on rigid steel plate to measure the pipe deformations and strains, as well as backfill surface displacement. The numerical analysis was used to simulate the experimental model using the finite element software program PLAXIS-3D. Findings. The results reveal that the most effective method which prevents stress on the buried flexible pipe was EPS post and beam system followed by EPS embracing the upper part of the pipe. The results obtained from the numerical analysis and the experiment demonstrate the same trend. The parametric study shows that EPS post and beam blocks model has higher surface displacement than embracing the upper part of the pipe model, which is more effective in case of high rigidity of the pipe. Originality. Reducing stress on buried pipes using different geofoam shapes to find which one is the optimum method. Practical implications. Two configurations of EPS geofoam blocks – EPS block embracing the upper part of the pipe and EPS blocks post and beam system - ensure successful stress reduction and protect buried pipes
Development of composition of cementing slurry for fastening of low-cemented rocks
Authors: Kondrat Roman , Dremliukh Natalia , Khaidarova Liliya
Published: June 2021

Purpose. Improving the producing capacity and ensuring the stable operation of gas wells that develop unstable, low-cemented reservoirs by preventing the sand entry from the reservoir by means of creating the cement stone with the corresponding values of strength and permeability in the bottomhole formation zone. Methods. The technological characteristics of the cementing slurry and the formed cement stone are measured using standard recording equipment. The cementing slurry consistency is measured with a pycnometer, the cement mixture spread ability – using AzNII cone, water separation is measured according to standard methods (DSTU BV.2.7 – 86-99), and the time of the cementing slurry hardening is determined on a consistometer KTS-3. The ultimate parameters of the stone strength during bending are determined on a special device for testing linear objects in tension, and compression – on a PSU-10 hydraulic press. Findings. The cementing slurry composition for creating the cement stone with the corresponding values of compression strength and gas permeability in the bottomhole formation zone has been developed, which includes oilwell cement, expanded perlite, non-ionic surfactant, plasticizer and water. Dependences of the cement stone compression strength and the stone permeability coefficient on the proportion of expanded perlite in the cementing slurry solution have been revealed. It is recommended to use the proposed cementing slurry for creating a cement stone with specified values of compression strength and permeability in the expanded well shaft in the interval of the producing reservoir. Originality. The optimal proportion of the expanded perlite in the solution has been found, at which the corresponding values of the compression strength (up to 4 MPa) and gas permeability (up to 3.47 μm2) of the cement stone is provided. Practical implications. When using the developed composition, it is possible to increase the yield of wells with unstable reservoirs and improve their working conditions by preventing the sand entry from the reservoir into the well.
Quality evaluation and loss estimation at gravel quarries around the Qena Governorate, Egypt: A case study
Authors: Ali Mahrous A.M , Hassan Mohamed M.A , Kim Jung-Gyu , Kim Jong-Gwan
Published: June 2021

Purpose. In recent years in Egypt there has been a significant increase in the demand for building materials, particularly gravel which is employed in buildings, the base layer for road construction, and other industries. The quality of gravel that is deemed suitable for different purposes depends on the physical, chemical, and mechanical properties of the gravel; these aspects are determined according to the Egyptian Code, depending on the required application. Methods. Representative samples were collected from two working sides of the quarries, then they were processed in a laboratory to characterize the samples depending on the location and evaluate their properties with respect to the corresponding concrete and road codes. Findings. The findings indicate that the gravel tests were simple to conduct and that the gravel from these locations were suitable for constructed roads and to be used in mixture of asphalt and cement. Originality. The samples were collected from five quarries around the Qena Governorate, Egypt; each of these locations occupied areas ranging from approximately 100×100 or 200×100 m2. Practical implications. The loss of gravel at the studied quarries was found to be 32.88-44.06%. Abo-Teshet 1 exhibited the highest loss of gravel deposits with thicknesses ranging from 0.5 to 1.50 m, which was attributed to the fill layers.
Studying the influence of the carbon dioxide injection period duration on the gas recovery factor during the gas condensate fields development under water drive
Authors: Matkivskyi Serhii , Kondrat Oleksandr
Published: June 2021

Purpose. Studying the process of carbon dioxide injection at the boundary of the initial gas-water contact in order to slow down the formation water inflow into producing reservoirs and increase the final hydrocarbon recovery factors. Methods. To assess the influence on gas recovery factor of the duration of carbon dioxide injection period at the initial gas-water contact, a reservoir development is studied using the main Eclipse and Petrel hydrodynamic modeling tools of the Schlumberger company on the example of a hypothetical three-dimensional model of a gas-condensate reservoir. Findings. The dependence of the main technological indicators of reservoir development on the duration of the carbon dioxide injection period at the initial gas-water contact has been determined. It has been revealed that an increase in the duration of the non-hydrocarbon gas injection period leads to a decrease in the formation water cumulative production. It has been found that when injecting carbon dioxide, an artificial barrier is created due to which the formation water inflow into the gas-saturated intervals of the productive horizon is partially blocked. The final gas recovery factor when injecting carbon dioxide is 61.98%, and when developing the reservoir for depletion – 48.04%. The results of the research performed indicate the technological efficiency of carbon dioxide injection at the boundary of the initial gas-water contact in order to slow down the formation water inflow into producing reservoirs and increase the final hydrocarbon recovery factors for the conditions of a particular field. Originality. The optimal value of duration of the carbon dioxide injection period at the initial gas-water contact has been determined, which is 16.32 months based on the statistical processing of calculated data for the conditions of a particular field. Practical implications. The use of the results makes it possible to improve the existing technologies for the gas condensate fields development under water drive and to increase the final hydrocarbon recovery factor.