On optimization of growth from gas phase in a vertical reactor with account native convection to improve properties of films

2016 ◽  
Vol 12 (4) ◽  
pp. 712-725 ◽  
Author(s):  
Evgeny L. Pankratov ◽  
Elena A. Bulaeva
Keyword(s):  
Gas Phase ◽  
Heat Transport ◽  
Induction Heating ◽  
Design Methodology ◽  
Analytical Approach ◽  
Growth Zone ◽  
Epitaxial Layers ◽  
Content Type ◽  
Time Parameters ◽  
Account Variation

Purpose The purpose of this paper is to: analyze the changing properties of epitaxial layers, manufactured in the considered reactor, with the changing parameters of the growth taking into account native convection; and development of the most common analytical approach to describe the technological process. Design/methodology/approach In this paper a vertical reactor for gas phase epitaxy is considered that consists of an external casing, a keeper of substrate with a substrate and a spiral around the casing in area of the growth zone to generate induction heating in order to activate the chemical reactions in the decay of reagents and the growth of the epitaxial layer by using the reagents. The authors introduce an analytical approach to analyze nonlinear mass and heat transport with account variation in space and time parameters. Findings The authors find conditions to improve properties of epitaxial layers. Originality/value Growth regimes at atmospheric and low pressure have been compared and analyzed for their influence of the native convection on the growth of the epitaxial layers. Accounting for the calculated results, recommendations have been formulated to improve the properties of the epitaxial layers.

An analytical approach for analysis and optimization of formation of field-effect heterotransistors

2016 ◽  
Vol 12 (4) ◽  
pp. 578-604 ◽  
Author(s):  
Evgeny L. Pankratov ◽  
Elena A. Bulaeva
Keyword(s):  
Heat Transport ◽  
Technological Process ◽  
Multilayer Structure ◽  
Field Effect ◽  
Design Methodology ◽  
Analytical Approach ◽  
Charge Carriers ◽  
Cross Linking ◽  
Content Type ◽  
Time Parameters

Purpose The purpose of this paper is to analyze and optimize the formation of field-effect heterotransistors using analytical approach. The approach makes it possible to analyze mass and heat transport in a multilayer structure without cross-linking of solutions on interfaces between layers of the multilayer structure. The optimization makes it possible to decrease dimensions of the heterotransistors and to increase speed of transport of charge carriers during functioning of the transistors. Design/methodology/approach The authors introduce an analytical approach for analysis of mass and heat transport, which makes it possible to take into account at one time varying in space and time parameters of the transports (diffusion coefficient, heat conduction coefficient, etc.) and nonlinearity of processes. The approach enables analysis of mass and heat transport in a multilayer structure without cross-linking of solutions on interfaces between layers of the multilayer structure and optimises the technological process. The optimization means it is possible to decrease dimensions of field-effect heterotransistors. Findings In this paper the authors introduce an approach to manufacture a field-effect heterotransistor with inhomogeneous doping of channel. Some recommendations to optimize technological process to manufacture more compact distribution of concentration of dopant have been formulated. Originality/value The results are original and the paper provides an approach to the manufacture of a field-effect heterotransistor.

scholarly journals Modeling Epitaxial Layer Growth from Gas Phase for Analysis of Influence of Changing Technological Process with Variation in Growth Zone Heating

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
E. L. Pankratov
Keyword(s):  
Heat Transfer ◽  
Gas Phase ◽  
Technological Process ◽  
Epitaxial Layer ◽  
Analytical Approach ◽  
Growth Zone ◽  
Layer Growth ◽  
Nonstationary Heat ◽  
Epitaxial Layers ◽  
Nonstationary Heat Transfer

Abstract In this paper, we analyze the nonstationary heat transfer during growth of epitaxial layers in epitaxy reactors from the gas phase. Based on this analysis, we formulate several recommendations on organization of heating of the growth zone for increasing homogeneity of epitaxial layers. We introduce an analytical approach for analysis of heat transfer during the growth of epitaxial layers from the gas phase. The approach gives a possibility to simultaneously take into account the nonlinearity of heat transfer, as well as changes of their parameters both in space and time.

The role of Muslim women in managing the family during crisis: corona pandemic as a model

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Haifa F. Fawaris
Keyword(s):  
Significant Role ◽  
Design Methodology ◽  
Analytical Approach ◽  
Muslim Women ◽  
Muslim Woman ◽  
Content Type ◽  
Study Results ◽  
The Family ◽  
Mental Characteristics

Purpose This study aims to clarify the role of Muslim women in managing their families during the corona pandemic crisis. To achieve this aim, the researcher applied the descriptive and analytical approach. Design/methodology/approach The Muslim women have had a prominent position consistent with the physical, psychological and mental characteristics that Allah has created them. This status is shown by: affirming their rights in all areas of life; affirming everything that preserved the dignity of women before Islam; and correcting all the conditions that detracted their dignity before the advent of Islam and making them responsible in public Islamic life on the level of: preserving Islam, spreading the Islamic call and achieving the civilization advancement of the Muslim nation. Findings The study resulted in many significant results. The most important one of the study results was that, in the context of woman rights and responsibilities she had assumed in Islam, the Muslim woman had a prominent position in Islam. In addition, the mother in the Muslim family had a significant role as a leader, who is capable of managing the family in corona crisis and supporting family members in all aspects such as faith, intellectual endeavors, psychological, social and health, so that they are real leaders. Originality/value The study recommends carrying out educational studies that identify and show the role of institutions other than the family in managing emergency crises.

Resistive torque in permanent magnet couplings operating through a conductive wall

2017 ◽  
Vol 36 (4) ◽  
pp. 1120-1133
Author(s):  
Thomas Rezek Matsumoto ◽  
Ivan Chabu
Keyword(s):  
Permanent Magnet ◽  
Design Methodology ◽  
Analytical Approach ◽  
Eddy Currents ◽  
Experiment Data ◽  
Content Type ◽  
Analytical Formulation ◽  
Resistive Torque ◽  
Torque Transmission ◽  
Coupling Performance

Purpose The purpose of this paper is to propose an analytical approach to determine the resistive torque caused by a conductive wall between the rotors of axial permanent magnet couplings. In this configuration, relative motion between the coupling rotors and the wall generates a resistive torque that is a consequence of the induced eddy currents in this barrier. Therefore, such induced resistive torque implies a reduction in the permanent magnet coupling performance, that is, its torque transmission capacity. Design/methodology/approach The developed resistive torque analytical formulation was based on eddy-current brakes of previous studies. To validate the proposed method, tests were conducted in a prototype and results were compared with analytical ones. Findings The analytical method showed a good correlation with the experiment data. Furthermore, a major degradation of the coupling capability to transmit torque was found because of the conductive wall presence, enhancing the importance of predicting such phenomenon when designing these devices. Originality/value A novel direct assessment of the resistive torque while in motion is presented in this paper. These measurements were of great importance to accurately compare the analytical and experimental data.

Improving the accuracy of time-harmonic FE simulations in induction heating applications

2017 ◽  
Vol 36 (2) ◽  
pp. 526-534 ◽  
Author(s):  
Kevin McMeekin ◽  
Frédéric Sirois ◽  
Maxime Tousignant ◽  
Philippe Bocher
Keyword(s):  
Magnetic Properties ◽  
Induction Heating ◽  
Design Methodology ◽  
Surface Heat ◽  
Equivalent Model ◽  
Content Type ◽  
Time Harmonic ◽  
Prediction And Control ◽  
Precise Prediction ◽  
And Control

Purpose Surface heat treatment by induction heating (10-100 kHz) requires precise prediction and control of the depth of the induced phase transformation. This paper aims at identifying common issues with the measurement and modeling of magnetic properties used in induction heating simulations, and it proposes ways to improve the situation. Design/methodology/approach In particular, it is demonstrated how intrinsic magnetic properties (i.e. the B-H curve) of a sample can change during the magnetic characterization process itself, due to involuntary annealing of the sample. Then, for a B-H curve that is supposed perfectly known, a comparison is performed between multiple models, each one representing the magnetic properties of steel in time-harmonic (TH) finite element method simulations. Finally, a new model called “power-equivalent model” is proposed. This model provides the best possible accuracy for a known nonlinear and hysteretic B-H curve used in TH simulations. Findings By carefully following the guidelines identified in this paper, reduction of errors in the range of 5-10 per cent can be achieved, both at the experimental and modeling levels. The new “power-equivalent model” proposed is also expected to be more generic than existing models. Originality/value This paper highlights common pitfalls in the measurement and modeling of magnetic properties, and suggests ways to improve the situation.

Russian agon and the quest for theoretical sociology

foresight ◽  
2017 ◽  
Vol 19 (4) ◽  
pp. 376-385
Author(s):  
Sergey B. Kulikov
Keyword(s):  
Transition Economies ◽  
Design Methodology ◽  
Analytical Approach ◽  
Propositional Attitudes ◽  
Content Type ◽  
The Past ◽  
Knowledge Based ◽  
Epistemological Analysis ◽  
Practical Implications ◽  
Theoretical Developments

Purpose The purpose of this paper is to represent an epistemological analysis of Russian sociological scholarship. Design/methodology/approach The analytical approach that allows reducing the particular representations within the sum of propositions is the methodological base of the paper. Clearing of propositional attitudes explains the basic communications in a thought of researchers. The circle of grounds available to achievement of intuitively noticed purposes defines the preferences of researchers in general. Findings The author proves that the theoretical developments in the Russian sociology are possible as a derivative from the development of questions, which are raised nowadays in worldwide science, but possible in a view of original development of questions, which were raised in worldwide science in the past. Research limitations/implications The Russian sociology represents a part of the European humanities, which is based on the various forms of theoretical combat or agonality. Practical implications The author shows the ways out of the theoretical combat or agonality. Social implications The research clarifies the perspectives for increasing of the knowledge-based society in Russia. The author analyzes the concept of Russia as a paradigmatic society, particularly in the context of transition economies. Originality/value In general, the author concludes that the pro-argument with respect to theoretical developments is weaker than the contra-argument with respect to theoretical developments. This paper has revealed the model within which extreme positions can be reconciled.

scholarly journals Covid-19 protocols: assessing construction site workers compliance

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Michael Ayodele Olukolajo ◽  
Abiodun Kolawole Oyetunji ◽  
Ifeoluwa Benjamin Oluleye
Keyword(s):  
Research Method ◽  
Design Methodology ◽  
Analytical Approach ◽  
Preventive Measures ◽  
Construction Site ◽  
Construction Sites ◽  
Protective Measures ◽  
Content Type ◽  
Contact Precautions ◽  
Structured Questionnaire

Purpose This paper aims to investigate construction site workers’ compliance with various coronavirus (Covid-19) protocols while working on construction sites. Design/methodology/approach This survey was conducted at the end of the imposed lockdown following Nigeria’s upsurge of the Covid-19 pandemic. The survey research method was adopted for the study using a structured questionnaire administered to 246 construction site workers under strict Covid-19 preventive measures. The data was complemented through personal observations of the study site activities. The results were analysed using frequency tables and a factor analytical approach. Findings The preventive measures in place on construction sites can be classified into personal protective measures, good etiquette/manners, contact precautions and prompt actions. Although the workers claimed to be aware of the Covid-19 pandemic, their disposition towards the preventive measures on construction sites is worrisome. Hence, their level of compliance with the protocols could mitigate the spread of the virus. Originality/value This paper fulfils an identified gap to study the need to promote public health by mitigating the global pandemic’s spread in areas where social distancing cannot be easily observed.

scholarly journals Digital transformation: why companies resist what they need for sustained performance

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Johan Magnusson ◽  
Viktor Elliot ◽  
Johan Hagberg
Keyword(s):  
Case Studies ◽  
Clinical Studies ◽  
Design Methodology ◽  
Analytical Approach ◽  
Digital Transformation ◽  
Content Type ◽  
Organizational Resistance ◽  
Sustained Performance ◽  
Combination Of Methods ◽  
Practical Implications

Purpose The purpose of this study is to contribute to firms’ capabilities of digital transformation through the identification of strategies for digital decoupling and recoupling. Design/methodology/approach This paper reports from multiple studies using a combination of methods such as case studies and clinical studies. The method of analysis involves the revisiting of vignettes from interactions with practitioners with the purpose of analyzing patterns in responses to digital transformation. Findings The findings consist of four strategies used by organizations and individuals in the decoupling of digital from their existing operations. Digital decoupling affords the organization the possibility of remaining largely unaffected by digital transformation. The authors also present four digital recoupling strategies that are used to succeed with digital transformation. Research limitations/implications This study is limited by the analytical approach of drawing from multiple previous studies. The research implications consist primarily of a contribution to a better understanding of why and how digital transformation is constrained. Practical implications The four strategies of digital decoupling can be used to identify behavior in organizations that limit digital transformation. The four strategies of digital recoupling can be used to instigate a more successful digital transformation. Originality/value According to the authors’ knowledge, this study is the first to identify digital decoupling strategies as a micro-foundation for organizational resistance to digital transformation.

Interaction of Al2O3-Ag and Al2O3-Cu hybrid nanoparticles with water on convectively heated moving material

2020 ◽  
Vol 16 (6) ◽  
pp. 1651-1667 ◽  
Author(s):  
G.K. Ramesh ◽  
G.S. Roopa ◽  
SabirAli Shehzad ◽  
S.U. Khan
Keyword(s):  
Nusselt Number ◽  
Skin Friction ◽  
Heat Transport ◽  
Ag Nanoparticles ◽  
Design Methodology ◽  
Pure Water ◽  
Hybrid Nanoparticles ◽  
Governing Equations ◽  
Numerical Illustration ◽  
Content Type

PurposeThe aim of present work is to study the flow and heat transport structures of hybrid nanoparticles in a moving material. Two types of hybrid nanoparticles have been chosen namely Al2O3-Cu and Al2O3-Ag nanoparticles (90%) within 10% of pure water.Design/methodology/approachLeading governing equations are transformed through similarity technique and then computed for numerical illustration by applying RKF method.FindingsThe author observed that the skin friction value of Al2O3-Cu/water case is lesser in comparison to the values of Nusselt number for Al2O3-Ag/water nanoparticles.Originality/valueThere exist no such study which addressed such phenomenon.

Revisiting Islamic education: the case of Indonesia

2014 ◽  
Vol 8 (4) ◽  
pp. 261-276 ◽  
Author(s):  
Mohd Roslan Mohd Nor ◽  
Maksum Malim
Keyword(s):  
Design Methodology ◽  
Analytical Approach ◽  
Significant Contribution ◽  
Islamic Education ◽  
Content Type ◽  
Future Studies ◽  
Library Research ◽  
The World ◽  
Long Time ◽  
Muslim Majority

Purpose – The purpose of this study is to attempt to examine the aims and objectives outlined in the formation of Islamic education in Indonesia. This study also looks at the development of Islamic education in general and the various approaches taken by the Indonesian Government. Design/methodology/approach – This study has mainly used a library research methodology. The data relevant to the study were collected and analysed by using an analytical approach. Findings – The study found that there is a significant contribution from the Ministry in formulation of Islamic Education policy in Indonesia. Originality/value – Indonesia is the largest Muslim majority country in the world. Islamic education in Indonesia has been around for a long time. In modern days, many have tried to study on Islamic education in terms of philosophy and objectives to be achieved. This study addresses the Islamic education in Indonesia; hence, it provides values for readers, researchers and those who are involved in future studies of this country.

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