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1 – 10 of 71Wojciech Konior, Romana Ratkiewicz and Jan Kotlarz
This paper aims to review the current knowledge about the neutral component of the local interstellar medium (LISM), which due to the resonant charge exchange, photoionization and…
Abstract
Purpose
This paper aims to review the current knowledge about the neutral component of the local interstellar medium (LISM), which due to the resonant charge exchange, photoionization and electron impact ionization processes has a profound impact on the heliosphere structure.
Design/methodology/approach
This work is based on the heliospheric literature review.
Findings
The summary of four major effects of neutral hydrogen atoms penetrating solar wind (SW), i.e. the disappearance of the complicated flow structure; the emergence of “hydrogen wall” in front of the heliopause (HP); decreasing distance of termination shock (TS), HP and bow shock (BS) layer from the Sun; and recently discovered by the Interstellar Boundary Explorer mission, a region of enhanced energetic neutral atom (ENA) emission seen in all sky maps as a ribbon.
Practical implications
In the context of constantly developing space technologies in aerospace engineering and prospective deep space missions, there is a need of general reviews about the interstellar space surroundings of the Sun and gathering the knowledge to help in theoretical, numerical and experimental investigations such as the optimization of the scientific equipment and spacecraft structure to work in specific conditions.
Originality/value
The survey encapsulate basic and relevant processes playing an important role in the physics of the nearest surroundings of the Sun and the latest results of numerical and experimental investigations focused on the neutral LISM component and its influence on the heliosphere, which is strongly desired in future works. Until now, not many of such reviews have been done.
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Romana Ratkiewicz, Wojciech Konior and Jan Kotlarz
The purpose of the paper is to give a brief description of the new topic introduced for the first time at the EASN Conferences.
Abstract
Purpose
The purpose of the paper is to give a brief description of the new topic introduced for the first time at the EASN Conferences.
Design/methodology/approach
The topic concerns the heliosphere, the nearest surrounding of the Sun and thus the nearest vicinity of the Earth. The heliosphere is created due to the interaction between the solar wind and the local interstellar medium.
Findings
This paper does not include any new information about the heliosphere and only introduces a new topic to this journal. It is briefly shown how heliospheric structures are formed, what factors affect a shape of the heliosphere, what measurements are made by Ulysses, Voyager and IBEX space missions (important for the heliosphere modeling) and how obtained data are used to validate theoretical results.
Practical implications
To categorize the paper under one of these classifications, research paper, viewpoint, technical paper, conceptual paper, case study, literature review or general review, the authors chose a paper type, general review, as the closest category to this paper. However, it is not a purpose of this paper to provide an extensive review of the community efforts to investigate the physical processes in the vicinity of the heliosphere interface. This is mostly a status report.
Originality/value
As the new topic in this journal, the article introduces in detail only a small number of aspects connected with heliosphere models. Interplanetary and interstellar magnetic field structures are primarily described. Other factors are only mentioned.
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Jan Kotlarz, Romana Ratkiewicz and Wojciech Konior
This paper aims to demonstrate the impact of interstellar (IS) magnetic field on stellar shocks existence, shape and size in the stellar wind (SW) vs interstellar medium (ISM…
Abstract
Purpose
This paper aims to demonstrate the impact of interstellar (IS) magnetic field on stellar shocks existence, shape and size in the stellar wind (SW) vs interstellar medium (ISM) numerical models.
Design/methodology/approach
Comparison of hydrodynamics (HD) and magnetohydrodynamic (MHD) models results with or without ISM magnetic field, its intensity and ISM parameters.
Findings
ISM magnetic field facilitates formation and stabilises bow shocks around all astrophysical objects. ISM magnetic field may also be one of the reasons for a bow shock existence around the Sun.
Practical implications
ISM magnetic field should be implemented in MHD and future kinetic numerical models of the SW interaction with ISM plasma.
Originality/value
This paper presents the results of HD and MHD models of bow shocks and the importance of ISM magnetic field implementation, according to astronomical bow shock observations. The study also presents a review of the most important papers showing the numerical results of bow shock formation.
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The paper seeks to propose and analyze a new electrostatic ramjet space engine.
Abstract
Purpose
The paper seeks to propose and analyze a new electrostatic ramjet space engine.
Design/methodology/approach
The upper atmosphere (85‐1,000 km) is extremely dense in ions (millions per cubic cm). The interplanetary medium contains positive protons from the solar wind. A charged ball collects the ions (protons) from the surrounding area and a special electric engine accelerates the ions to achieve thrust or decelerates the ions to achieve drag. The thrust may have a magnitude of several Newtons. If the ions are decelerated, the engine produces a drag and generates electrical energy. The theory of the new engine is developed.
Findings
It is shown that the proposed engine driven by a solar battery (or other energy source) cannot only support satellites in their orbit for a very long time but can also work as a launcher of space apparatus. The latter capability includes launch to high orbit, to the Moon, to far space, or to the Earth's atmosphere (as a return thruster for space apparatus or as a killer of space debris). The proposed ramjet is very useful in interplanetary trips to far planets because it can simultaneously produce thrust or drag and large electric energy using the solar wind.
Originality/value
Two scenarios, launch into the upper Earth atmosphere and an interplanetary trip, are simulated and the results illustrate the excellent possibilities of the new concept.
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Joseph C. Keller and Edwin C. Keller
Apparently, all space probes, but no planets, are subject to a constant quasigravitational force that is equivalent to the force on photons that causes the Hubble red shift. Also…
Abstract
Apparently, all space probes, but no planets, are subject to a constant quasigravitational force that is equivalent to the force on photons that causes the Hubble red shift. Also, the surface gravity of protons, determined by the Heisenberg Uncertainty Principle, causes a barrier at about 53 astronomical units from the sun. Pioneer 10 generated a “space warp” as it crossed this barrier.
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The purpose of the present article is to obtain the similarity solution for the shock wave generated by a piston propagating in a self-gravitating nonideal gas under the impact of…
Abstract
Purpose
The purpose of the present article is to obtain the similarity solution for the shock wave generated by a piston propagating in a self-gravitating nonideal gas under the impact of azimuthal magnetic field for adiabatic and isothermal flows.
Design/methodology/approach
The Lie group theoretic method given by Sophus Lie is used to obtain the similarity solution in the present article.
Findings
Similarity solution with exponential law shock path is obtained for both ideal and nonideal gas cases. The effects on the flow variables, density ratio at the shock front and shock strength by the variation of the shock Cowling number, adiabatic index of the gas, gravitational parameter and nonidealness parameter are investigated. The shock strength decreases with an increase in the shock Cowling number, nonidealness parameter and adiabatic index, whereas the strength of the shock wave increases with an increase in gravitational parameter.
Originality/value
Propagation of shock wave with spherical geometry in a self-gravitating nonideal gas under the impact of azimuthal magnetic field for adiabatic and isothermal flows has not been studied by any author using the Lie group theoretic method.
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Chandrasekar Pichaimuthu and Ganesh Swaminathan
The Purpose of this study to examine the magneto hydrodynamics (MHD) using the analytical and numerical tool. In recent years, MHD growing tremendously due to the presence of…
Abstract
Purpose
The Purpose of this study to examine the magneto hydrodynamics (MHD) using the analytical and numerical tool. In recent years, MHD growing tremendously due to the presence of multidisciplinary application in solving the tedious problems in the viscous flow.
Design/methodology/approach
The flows between the parallel plates under the steady inclined magneto hydrodynamic force were studied under the presence of different hall current and pressure gradient. The system was designed with the Darcian porous medium subjected to the incompressible flow. To analyse the flow reactions through stationary parallel plates, the governing equations were used using the integral transformation.
Findings
The velocity of the flows depends on the Hall parameter. As the intensity of the magnetic field increases the velocity of the flow is affected significantly. On the other hand, the radiation parameters also affect the flow of any medium through the porous medium.
Practical implications
Implementation of the Laplace and Fourier transform increases the reliability of the obtained results and further decreases the uncertainty during the measurement of the velocity of the flow without any restraints.
Originality/value
From the evident results, it is clear that the proposed MHD model can be applied to several operations of the fluid dynamic models. Further, the application of this technique will decrease the uncertainty in the results compared to the conventional computational models and other finite element and difference approaches.
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Shafiqul Alam and Pavitra Dhamija
The transition from Industry 3.0 to the fourth industrial revolution was a big jump that created a vacuum in many developing countries. Drawing upon institutional theory and…
Abstract
Purpose
The transition from Industry 3.0 to the fourth industrial revolution was a big jump that created a vacuum in many developing countries. Drawing upon institutional theory and resource-based view theory, the current study proposes a theoretical model linking the institutional pressures and resources (workforce skills) in context to the apparel industry of Bangladesh.
Design/methodology/approach
This study adopts a qualitative approach involving 20 semi-structured interviews, followed by thematic analysis using NVivo 12 software. The researchers impose both deductive and inductive thematic analysis to generate themes. The data analysis involves various stages applying the phenomenological approaches.
Findings
Institutional pressures (coercive) positively influences the workforce skills (technical and managerial) in the fourth industrial revolution in Bangladesh apparel manufacturing industry; institutional pressures (normative) is positively related to the workforce skills (technical and managerial) in 4IR in Bangladesh apparel manufacturing industry; institutional pressures (mimetic) has shown a positive association with the workforce skills (technical and managerial) in 4IR in Bangladesh apparel manufacturing industry; workforce skills (technical and managerial) are positively influencing the development of human resource capabilities in fourth industrial revolution in Bangladesh apparel manufacturing industry.
Originality/value
This paper is the first of its kind to offer a thematic analysis on human resource development 4.0 in the apparel industry of Bangladesh. The study provides an understanding of the role of institutional pressure on workforce skill development and the adoption of 4IR technology.
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Scholarship on language teacher knowledge and critical digital literacy. Using a grounded theory approach, semi-structured online presentations of students, classroom observations…
Abstract
Purpose
Scholarship on language teacher knowledge and critical digital literacy. Using a grounded theory approach, semi-structured online presentations of students, classroom observations and their responses to multimedia tools such as movies and literature were analysed. As part of the study, 150 students pursuing undergraduate degree in engineering were assigned two assignments involving science fiction movies and hyperreal literature as part of an experiential strategy. A survey was conducted before and after the study to evaluate the change in students’ perception towards the use of technology and multimedia in language classrooms as well as their awareness of technological dependency in the postmodern world. The findings show that student cognition of AI and technological dependency is a complex and emergent system, and that, despite current literacy education scholarship stressing digital literacy as a social and critical praxis, technology is treated in a mostly functional, rather than a critical manner in a standard university language classroom. The results of this study suggest that the disadvantages of a realistic approach to teaching digital composition can be avoided by creating other forms of educational materials that adhere to critical digital literacies sense, such as posthuman literary works and science fiction film.
Design/methodology/approach
This study is primarily qualitative and empirical, focussing on the analysis of student responses to classroom assignments and semi-structured online presentations and responses to multimedia tools such as movies and online literature. A pilot study was performed among the engineering students of Vellore Institute of Technology, Vellore, India, to better understand engineering students’ perceptions and attitudes towards teaching English as a second language using emerging technology, with the aim of improving language abilities, writing skills, imagination and overall personality. One hundred and fifty (150) students were assigned two assignments as part of an experiential strategy. Owing to the COVID-19 pandemic, Microsoft Teams was used as the platform for assessment and observation. As part of their learning challenge, students were required to watch the movies “Her”, “Interstellar” and “Bandersnatch” and write a technical report outlining some of the major observations on technology and AI. Secondly, as part of their learning challenge, students were required to read Oliver Sacks’ “The Machine Stops” and comment on his perspectives on technological dependency. This was supplemented by assessment tests and assignments focussing on the digital nature of the global education system. Another survey was conducted at the end of the study to evaluate the change in students’ perception towards the use of technology and multimedia in language classrooms as well as their awareness of technological dependency in the postmodern world. Owing to the posthuman and hyperreal nature of the movies and texts, students were introduced to the theories of Marshall McLuhan and Jean Baudrillard to better understand the chosen works.
Findings
In the posthuman era, where digital technologies are at their peak, English language teachers select appropriate teaching resource materials based on the needs of the students and do their utmost to combine them with technology to make their teaching more engaging and efficient. Thanks to the current craze for Digital Humanities, not just English language teaching but also literature classroom teaching has experienced several paradigm shifts. This has raised the need for English teachers and professionals on the job market. Given this context, and in particular, to raise knowledge among engineering students of their critical position in the literary job sector, two tasks were assigned to students in the Language Classroom. These tasks included integrating technology into language studies and literature, instilling imagination, honing literary skills and facilitating the development of a comprehensive approach to life and potential endeavours.
Originality/value
As evident from the study and literature review, the introduction of emerging technology in Language Classrooms has grown in popularity, but it has yet to be incorporated into Language Classrooms that focus on the comprehensive development of students, especially in India. Furthermore, proof of interactions between digital learning and teaching practices and anticipated results, effects and impacts was gathered to make the Language Classroom more social, inspiring and engaging, but little more. As a result, we see a lot of potential for research in this field, particularly concerning the most recent language studies advancements about Digital Humanities.
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