Monitoring the plasmapause dynamics at LEO

2021 ◽  
Author(s):  
Balázs Heilig ◽  
Claudia Stolle ◽  
Jan Rauberg ◽  
Guram Kervalishvili
Keyword(s):  
Small Scale ◽  
Topside Ionosphere ◽  
Dynamic Coupling ◽  
Ion Drift ◽  
The Past ◽  
Scale Field ◽  
Funded Project ◽  
Mutual Relations ◽  
Langmuir Probe Measurements ◽  
Probe Measurements

<p>In the past decades researchers have revealed links between a series of sub-auroral ionospheric phenomena and the plasmapause (PP) dynamics, such as the mid-latitude ionospheric trough (MIT) and the associated sub-auroral temperature enhancement (SETE), the light-ion trough (LIT), the sub-auroral ion drift (SAID) or the more intense sub-auroral polarisation stream (SAPS), and most recently, the inner boundary of small-scale field-aligned currents (SSFACs). Most of these phenomena can be directly observed by the Swarm constellation of ESA at LEO. Thus, Swarm presents a unique opportunity to study the relations between them and also their relation to the PP dynamics.</p><p>In a recent Swarm DISC project, PRISM (Plasmapause Related boundaries in the topside Ionosphere as derived from Swarm Measurements), three new products have been developed. Two products characterise the MIT (and the associated SETE). The MITx_LP utilises the Langmuir probe measurements of electron density and temperature, while the MITxTEC product derives the MIT properties from GPS TEC observations. The third product, PPIxFAC provides information on the location and the main characteristics of the equatorial boundary of SSFACs, and it also includes a proxy for the location of the PP at MLT midnight.</p><p>In this presentation we introduce the above Swarm L2 products, present the results of a comparative study aiming at revealing their mutual relations and also their dynamic coupling to the PP. Then we demonstrate how the observations of all these ionospheric phenomena combined can be used to develop an improved proxy for monitoring the PP dynamics at LEO as one of the goals of our new ESA-funded project PLASMA.</p>

Federal Uncertainty or Inconsistency? Releasing the New Agricultural-Environmental Biotechnology Into the Fields

2000 ◽  
Vol 19 (1) ◽  
pp. 77-88 ◽  
Author(s):  
Patrick Stewart ◽  
A. Ann Sorensen
Keyword(s):  
Environmental Biotechnology ◽  
Regulatory System ◽  
The United States ◽  
Field Trials ◽  
Small Scale ◽  
The Past ◽  
Scale Field ◽  
Potential Risks ◽  
Biotechnology Products ◽  
By Products

This article reviews the regulation of the new agricultural-environmental biotechnology and recent changes in the regulatory framework in the United States. Regulations put in place in the mid-1980s were established due to concern over potential risks posed by products not yet released into the environment. Now that over a thousand small-scale field trials have been carried out and various new agricultural-environmental biotechnology products have been in farmers' fields for the past several years, questions are being raised about the current regulatory system by both proponents, who want greater deregulation due to the relative absence of ecological harm, and opponents, who warn against potential environmental catastrophe due to greater variety and amount of new agricultural-environmental products being released. Therefore, we focus on triggers for regulation, which appear to hinge on the “naturalness” of a product, and trends in field release of these products.

Lessons Learned from Small Scale Field Test Demonstrating CO2 EOR and Geologic Storage at Wellington Field in Southern Kansas

2019 ◽  
Author(s):  
Yevhen Holubnyak ◽  
Willard Watney ◽  
Tiraz Birdie ◽  
Dana Wreath ◽  
George Tsoflias ◽  
...  
Keyword(s):  
Field Test ◽  
Lessons Learned ◽  
Small Scale ◽  
Geologic Storage ◽  
Scale Field ◽  
Co2 Eor

Forecasting of Tornadoes and Downbursts

2020 ◽  
Author(s):  
Djordje Romanic
Keyword(s):  
Chaos Theory ◽  
Prediction Models ◽  
Weather Prediction ◽  
Small Scale ◽  
Weather Forecasts ◽  
Wind Speeds ◽  
The Past ◽  
Extreme Wind ◽  
Extreme Wind Speeds ◽  
Numerical Weather Prediction Models

Tornadoes and downbursts cause extreme wind speeds that often present a threat to human safety, structures, and the environment. While the accuracy of weather forecasts has increased manifold over the past several decades, the current numerical weather prediction models are still not capable of explicitly resolving tornadoes and small-scale downbursts in their operational applications. This chapter describes some of the physical (e.g., tornadogenesis and downburst formation), mathematical (e.g., chaos theory), and computational (e.g., grid resolution) challenges that meteorologists currently face in tornado and downburst forecasting.

scholarly journals PyroMEMS as Future Technological Building Blocks for Advanced Microenergetic Systems

Micromachines ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 118
Author(s):  
Jean-Laurent Pouchairet ◽  
Carole Rossi
Keyword(s):  
Building Block ◽  
Building Blocks ◽  
Small Scale ◽  
Technological Evolution ◽  
Research Groups ◽  
Function Block ◽  
The Past ◽  
New Methods ◽  
Safety And Reliability ◽  
Electronically Controllable

For the past two decades, many research groups have investigated new methods for reducing the size and cost of safe and arm-fire systems, while also improving their safety and reliability, through batch processing. Simultaneously, micro- and nanotechnology advancements regarding nanothermite materials have enabled the production of a key technological building block: pyrotechnical microsystems (pyroMEMS). This building block simply consists of microscale electric initiators with a thin thermite layer as the ignition charge. This microscale to millimeter-scale addressable pyroMEMS enables the integration of intelligence into centimeter-scale pyrotechnical systems. To illustrate this technological evolution, we hereby present the development of a smart infrared (IR) electronically controllable flare consisting of three distinct components: (1) a controllable pyrotechnical ejection block comprising three independently addressable small-scale propellers, all integrated into a one-piece molded and interconnected device, (2) a terminal function block comprising a structured IR pyrotechnical loaf coupled with a microinitiation stage integrating low-energy addressable pyroMEMS, and (3) a connected, autonomous, STANAG 4187 compliant, electronic sensor arming and firing block.

Langmuir Probe Measurements in the WEGA Stellarator

2004 ◽  
Vol 44 (7-8) ◽  
pp. 650-655 ◽  
Author(s):  
K. Horvath ◽  
J. Lingertat ◽  
M. Laux ◽  
F. Wagner
Keyword(s):  
Langmuir Probe ◽  
Langmuir Probe Measurements ◽  
Probe Measurements

Langmuir probe measurements aboard the International Space Station

2016 ◽  
Vol 56 (8) ◽  
pp. 1082-1089 ◽  
Author(s):  
B. Kirov ◽  
S. Asenovski ◽  
D. Bachvarov ◽  
A. Boneva ◽  
V. Grushin ◽  
...  
Keyword(s):  
International Space Station ◽  
Langmuir Probe ◽  
Space Station ◽  
International Space ◽  
Langmuir Probe Measurements ◽  
Probe Measurements

scholarly journals The transient swimming of a waving sheet

2009 ◽  
Vol 466 (2113) ◽  
pp. 107-126 ◽  
Author(s):  
On Shun Pak ◽  
Eric Lauga
Keyword(s):  
Fluid Flow ◽  
Reynolds Numbers ◽  
Geometrical Model ◽  
Small Scale ◽  
Transient Effects ◽  
Initial Value ◽  
Low Reynolds Numbers ◽  
The Past ◽  
Low Reynolds Number Swimming ◽  
Low Reynolds

Small-scale locomotion plays an important role in biology. Different modelling approaches have been proposed in the past. The simplest model is an infinite inextensible two-dimensional waving sheet, originally introduced by Taylor, which serves as an idealized geometrical model for both spermatozoa locomotion and ciliary transport in Stokes flow. Here, we complement classic steady-state calculations by deriving the transient low-Reynolds number swimming speed of such a waving sheet when starting from rest (small-amplitude initial-value problem). We also determine the transient fluid flow in the ‘pumping’ setup where the sheet is not free to move but instead generates a net fluid flow around it. The time scales for these two problems, which in general govern transient effects in transport and locomotion at low Reynolds numbers, are also derived using physical arguments.

Sign in / Sign up

Export Citation Format

Share Document