Double Langmuir frequency radiation due to transformation processes in turbulent plasma

2014 ◽  
Vol 81 (2) ◽  
Author(s):  
V. N. Pavlenko ◽  
V. G. Panchenko ◽  
N. A. Beloshenko
Keyword(s):  
Pump Wave ◽  
Langmuir Wave ◽  
Transformation Process ◽  
Turbulent Plasma ◽  
Sound Waves ◽  
Double Electron ◽  
Langmuir Frequency ◽  
Transverse Electromagnetic ◽  
Transformation Processes ◽  
Frequency Radiation

We investigate the transformation process of longitudinal Langmuir wave into the transverse electromagnetic wave in turbulent plasma subjected to an upper hybrid pump. The case, when upper hybrid pump wave decays into daughter and ion – sound waves is considered. The transformation of the Langmuir wave into electromagnetic one is considered as the possible mechanism of energy radiation from the plasma. It is shown that the frequency of such radiation is chosen to be near double electron Langmuir frequency 2ωpe. These results give us the possibility to explain the nature of radiation from the laboratory and cosmic plasmas (particularly, from the solar crown).

scholarly journals Influence of Inhomogeneity on Transformation and Radiation Processes in Plasma with Upper Hybrid Pump

2019 ◽  
Vol 64 (9) ◽  
pp. 814
Author(s):  
V. G. Panchenko ◽  
P. V. Porytsky
Keyword(s):  
Pump Wave ◽  
Inhomogeneous Plasma ◽  
Parametric Instability ◽  
Langmuir Wave ◽  
Wave Transformation ◽  
Transformation Coefficient ◽  
Radiation Emission ◽  
Parametric Decay ◽  
Radiation Processes ◽  
Transverse Electromagnetic

On the basis of the kinetic theory of fluctuations, the processes of the longitudinal Langmuir wave transformation into a transverse electromagnetic wave in the turbulent inhomogeneous plasma have been studied. The plasma turbulence is assumed to arise owing to the parametric decay of the upper hybrid pump wave into a daughter wave and electron-drift oscillations. The transformation coefficient under the parametric instability saturation conditions is determined. The intensity of the electromagnetic radiation emission from the plasma is calculated, and its dependence on the plasma and pump wave parameters is found.

THE IMPACT OF UKRAINE'S EXCISE DUTY POLICY ON THE TRANSFORMATION PROCESSES OF THE TOBACCO MARKET

2020 ◽  
Vol 2020 (10) ◽  
pp. 19-33
Author(s):  
Nadiia NOVYTSKA ◽  
◽  
Inna KHLIEBNIKOVA ◽  
Keyword(s):  
Structural Changes ◽  
Tax Avoidance ◽  
Transformation Process ◽  
State Regulation ◽  
Tobacco Products ◽  
Excise Duty ◽  
Increasing Demand ◽  
High Level ◽  
The Impact ◽  
Transformation Processes

The market of tobacco products in Ukraine is one of the most dynamic and competitive. It develops under the influence of certain factors that cause structural changes, therefore, the aim of the article is to conduct a comprehensive analysis of transformation processes in the market of tobacco and their alternatives in Ukraine and identify the factors that cause them. The high level of tax burden and the proliferation of alternative products with a potentially lower risk to human health, including heating tobacco products and e-cigarettes, are key factors in the market’s transformation process. Their presence leads to an increase in illicit turnover of tobacco products, which accounts for 6.37% of the market, and the gradual replacement of cigarettes with alternative products, which account for 12.95%. The presence on the market of products that are not taxed or taxed at lower rates is one of the reasons for the reduction of excise duty revenues. According to the results of 2019, the planned indicators of revenues were not met by 23.5%. Other reasons for non-fulfillment of excise duty revenues include: declining dynamics of the tobacco products market; reduction in the number of smokers; reorientation of «cheap whites» cigarette flows from Ukraine to neighboring countries; tax avoidance. Prospects for further research are identified, namely the need to develop measures for state regulation and optimization of excise duty taxation of tobacco products and their alternatives, taking into account the risks to public health and increasing demand of illegal products.

scholarly journals Macro- and Micronutrient Cycling and Crucial Linkages to Geochemical Processes in Mangrove Ecosystems

2021 ◽  
Vol 9 (5) ◽  
pp. 456
Author(s):  
Daniel M. Alongi
Keyword(s):  
Transformation Process ◽  
Early Diagenesis ◽  
P Availability ◽  
Geochemical Processes ◽  
Nutrient Cycles ◽  
Physiological Mechanisms ◽  
Retention Efficiency ◽  
Mangrove Ecosystems ◽  
N Metabolism ◽  
Transformation Processes

High mangrove productivity is sustained by rapid utilization, high retention efficiency and maximum storage of nutrients in leaves, roots, and soils. Rapid microbial transformations and high mineralization efficiencies in tandem with physiological mechanisms conserve scarce nutrients. Macronutrient cycling is interlinked with micronutrient cycling; all nutrient cycles are linked closely to geochemical transformation processes. Mangroves can be N-, P-, Fe-, and Cu-limited; additions of Zn and Mo stimulate early growth until levels above pristine porewater concentrations induce toxicity. Limited nutrient availability is caused by sorption and retention onto iron oxides, clays, and sulfide minerals. Little N is exported as immobilization is the largest transformation process. Mn and S affect N metabolism and photosynthesis via early diagenesis and P availability is coupled to Fe-S redox oscillations. Fe is involved in nitrification, denitrification and anammox, and Mo is involved in NO3− reduction and N2-fixation. Soil Mg, K, Mn, Zn and Ni pool sizes decrease as mangrove primary productivity increases, suggesting increasing uptake and more rapid turnover than in less productive forests. Mangroves may be major contributors to oceanic Mn and Mo cycles, delivering 7.4–12.1 Gmol Mn a−1 to the ocean, which is greater than global riverine input. The global Mo import rate by mangroves corresponds to 15–120% of Mo supply to the oceanic Mo budget.

Industry 4.0 From a Management Perspective

2022 ◽  
pp. 1-18
Author(s):  
Ilknur Taştan Boz ◽  
Özden Ibrahimağaoğlu
Keyword(s):  
Industry 4.0 ◽  
Business Models ◽  
Business Processes ◽  
Industrial Revolution ◽  
Organizational Structures ◽  
Transformation Process ◽  
Management Perspective ◽  
Fundamental Transformation ◽  
Transformation Processes ◽  
The Internet Of Things

Industries have undergone three fundamental transformation processes that were revolutionary. Following these processes, industries have been confronted with the phenomenon of Industry 4.0, known as the 4th Industrial Revolution, that is acknowledged as a new transformation process. The basic dynamics of this phenomenon include smart robots, simulation, the internet of things, cloud, additive manufacturing, and big data. It is of utmost importance for businesses that are involved in this process, that are new and trying to adapt to the process, to be prepared and adapt to the effects of Industry 4.0 dynamics. These dynamics lead to significant developments in business models, business processes, organizational structures, employees, and human resource processes. When Industry 4.0 and its dynamics are evaluated in general, businesses that follow the process and make necessary managerial adjustments will be ahead of the competition.

Actors

2019 ◽  
pp. 42-52
Author(s):  
Wolfgang Merkel ◽  
Hans-Jürgen Wagener
Keyword(s):  
Social Sciences ◽  
Action Theory ◽  
System Change ◽  
Transformation Process ◽  
Theoretical Approaches ◽  
Subjective Assessments ◽  
Collective Decisions ◽  
The Social ◽  
Transformation Processes ◽  
Empirical Approaches

Methodological individualism is widely accepted in the social sciences as a fundamental theoretical paradigm. In this context, it means attributing collective decisions or societal acceptance to individual behaviour. From the perspective of action theory, the outcome of transformation processes therefore depends less on objective circumstances (structures) or power configurations than on the subjective assessments, strategies, and actions of the relevant actors. As a rule, elites are the predominant actors in political and in economic system change. Since in the transformation process the basic institutions of society are generally reformulated at the negotiating table, much of the attention is centred on negotiation theories that use game-theoretical tools. By contrast to modernization, culturalist, and structuralist theories, actor theories set out from the micro and meso levels of the actors. Different approaches can be discerned. Historical-empirical approaches do not go beyond the description of transformation processes. Economic public choice approaches assume rather simplistic motivational structures of actors. In actor-centred institutionalism, the social sciences find a typical fusion of paradigms: action- and structure-theoretical approaches are combined.

Transformation Strategies for Shared Service Centers in the Public Sector

2009 ◽  
pp. 35-50
Author(s):  
Haiko van der Voort ◽  
Hans de Bruijn ◽  
Marijn Janssen
Keyword(s):  
Public Administration ◽  
Economies Of Scale ◽  
Transformation Process ◽  
Policy Network ◽  
Support Functions ◽  
The Public ◽  
Key Stakeholders ◽  
Cost Reductions ◽  
Shared Service ◽  
Transformation Processes

This chapter presents a set of critical choices for initiating a Shared Service Center (SSC) in a large public organization and the management of the transformation process towards it. A move to concentratingorganizational support functions in SSCs in public administration is encouraged by successes in the private sector. There is a lot to gain by concentrating functions including improved services through specialization, efficiencies through standardization, and cost reductions through economies of scale. Yet the transformation process does not resemble the simplicity of the concept of SSC and many challenges need to be bridged. In this chapter, the complexities of transformation processes of the introduction of a government wide SSC for human resource management are studied. By analyzing the perceptions of key stakeholders from a policy network theoretical lens, we found some major patterns determining success or failure in both designing and implementing SSCs. By listing these, we aim to clarify the complexities of transformation processes towards SSCs in public administration and provide some strategic suggestions for these transformations.

scholarly journals High frequency ion sound waves associated with Langmuir waves in type III radio burst source regions

2004 ◽  
Vol 11 (3) ◽  
pp. 411-420 ◽  
Author(s):  
G. Thejappa ◽  
R. J. MacDowall
Keyword(s):  
Short Wavelength ◽  
Langmuir Wave ◽  
Linear Process ◽  
Radio Bursts ◽  
Sound Waves ◽  
Burst Source ◽  
Langmuir Waves ◽  
Type Iii ◽  
Resonant Wave ◽  
Source Regions

Abstract. Short wavelength ion sound waves (2-4kHz) are detected in association with the Langmuir waves (~15-30kHz) in the source regions of several local type III radio bursts. They are most probably not due to any resonant wave-wave interactions such as the electrostatic decay instability because their wavelengths are much shorter than those of Langmuir waves. The Langmuir waves occur as coherent field structures with peak intensities exceeding the Langmuir collapse thresholds. Their scale sizes are of the order of the wavelength of an ion sound wave. These Langmuir wave field characteristics indicate that the observed short wavelength ion sound waves are most probably generated during the thermalization of the burnt-out cavitons left behind by the Langmuir collapse. Moreover, the peak intensities of the observed short wavelength ion sound waves are comparable to the expected intensities of those ion sound waves radiated by the burnt-out cavitons. However, the speeds of the electron beams derived from the frequency drift of type III radio bursts are too slow to satisfy the needed adiabatic ion approximation. Therefore, some non-linear process such as the induced scattering on thermal ions most probably pumps the beam excited Langmuir waves towards the lower wavenumbers, where the adiabatic ion approximation is justified.

Decay Instability of an Electromagnetic Wave Incident on a Weakly-Inhomogeneous Magnetised Plasma

1982 ◽  
Vol 37 (2) ◽  
pp. 97-101
Author(s):  
Bhimsen K. Shivamoggi
Keyword(s):  
Electromagnetic Wave ◽  
Pump Wave ◽  
Low Frequency ◽  
Langmuir Wave ◽  
Density Perturbation ◽  
Threshold Value ◽  
Wave Incident ◽  
Ion Acoustic Wave ◽  
Decay Instability ◽  
Electromagnetic Wave Incident

Abstract This paper considers the parametric decay of an electromagnetic wave incident on a weakly-inhomogeneous magnetised plasma into a Langmuir wave and an ion-acoustic wave. The Vlasov model is used in order to calculate the low-frequency electron-density perturbation produced by the beating of the side-band modes with the pump wave. The results show that the threshold value of the pump wave to undergo a decay instability drops in the presence of an inhomogeneity in the plasma.

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