Global 6-dimensional hybrid-Vlasov modelling of the magnetosphere: First Vlasiator results

2021 ◽  
Author(s):  
Minna Palmroth ◽  
Urs Ganse ◽  
Markus Battarbee ◽  
Lucile Turc ◽  
Yann Pfau-Kempf ◽  
...  
Keyword(s):  
Boundary Conditions ◽  
Real Space ◽  
Space Physics ◽  
Small Scale ◽  
Global Dynamics ◽  
Ion Distributions ◽  
Dayside Magnetopause ◽  
The World ◽  
Kinetic Effects ◽  
New Phenomena

<p>Numerical simulations are key in modern space physics, as they can be used as 1) context to data, 2) predict future behaviour of the system, 3) understand the system using unforeseen boundary conditions, and increasingly also in 4) discovering new phenomena that are hard to be observed using point-wise satellite measurements. Especially, the discovery of new phenomena pertains to global systems, where phenomena of interest may be initiated far away from the point of observations. The most typical method of simulating the global solar wind - magnetosphere - ionosphere system is based on magnetohydrodynamics (MHD), which is however not representing the actual plasma behaviour in locations where kinetic physics becomes important. Such regions are e.g., the foreshock - magnetosheath interaction, reconnection, and the inner magnetosphere.</p><p>Vlasiator is the world’s first and so far the only global simulation based on the hybrid-Vlasov approach that simulates the ion distributions accurately without noise. The simulation has, for computational reasons, been so far executed in 2D real space. Even so, the global 5D Vlasiator results have shown without a doubt that ion-kinetic effects cannot be neglected from the large scales, as small-scale phenomena affect large scales and vice versa. This scale coupling leads to phenomena that are not predicted using local simulations without proper boundary conditions, or with spacecraft measurements lacking the global context.</p><p>Here, we present the world’s first global 6-dimensional ion-kinetic global magnetospheric simulation run, accurate both locally and globally. The simulation box extends from the dayside to the nightside, and includes global dynamics and both dayside and nightside reconnection regions. We will investigate unambiguously for the first time the dayside magnetopause reconnection as driven by the kinetic variations in the magnetosheath, and tail reconnection as driven by magnetic flux from the dayside.</p>

Land Grabs: The Politics of the Land Rush Across Africa

2018 ◽  
Author(s):  
Pauline Peters
Keyword(s):  
World Bank ◽  
Private Equity ◽  
Large Scale ◽  
Small Scale ◽  
Global Dynamics ◽  
World Bank Group ◽  
African Countries ◽  
The World Bank ◽  
The World ◽  
Land Grabs

The currently extensive land appropriation across Africa signals the most radical shift in the distribution and tenure status of land since colonial times. The first alarms about “land grabs” by foreigners were raised by advocacy groups around 2007–2008. The search for land, always watered land, by foreign agents is driven by concerns about rising food and oil prices, and most of the acquired land is put under food crops, biofuels, and flex crops. The promises of profits from the exceedingly low price of land across Africa, as well as the rising demand for the mentioned crops, have also attracted speculation by private equity funds. With more detailed research on the processes and effects of this shift in rights to (and use of) land, the focus on a “new scramble” by foreign agents has extended to the multiple processes involved in the increasing demand for Africa’s land, internally and externally. The increase in acquisition of land by international agents, not only for cultivation but for minerals, oil, timber, and so forth, exacerbates the accelerating demand for land within African countries by nationals such as salaried, middle-class people and politicians acquiring land for cultivation and for an investment fast increasing in value. The millions of small-scale users of largely “customary” land struggle to derive a livelihood from their smallholdings and access to dwindling and increasingly enclosed common land, including grazing and watering areas. These linkages among local, national, and global dynamics of land acquisition reveal mounting socioeconomic and political inequality across Africa. In addition, research on the land rush reveals competing visions for African agriculture, invoking the debate of large- versus small-scale agricultural futures, a long-standing question of agrarian studies now being asked within much changed political-economic, social, and environmental conditions. Both macro-data and field studies show that most of the foreign acquired land is used for large-scale plantations, some of which include contract farming and outgrower schemes. Although, for a variety of reasons, some large land deals fold, the most recent Land Matrix data show most do move into production. Research on these large-scale projects has shown, however, that most fail to attain the projected aims of providing benefits to the countries and people from which they acquired the land. Most appropriated land was already in productive use by local users rather than “under-utilized” or “waste land” as described in many documents by investors and donors such as the World Bank; there were fewer benefits in the form of employment, higher and sustained income, and lower risk for most laborers, contract farmers, and outgrowers; far less infrastructure (schools, clinics, roads, etc.) built, as promised, for local populations; and output that is either exported or that proves unsuitable for the locales, with lower production value at lower efficiency compared with the land uses before the large-scale projects were put in place. These negative findings have to be set alongside the facts that the investors acquire the land at either extremely low cost (usually lease rather than sale) or even free, and receive tax, import/export and other “incentives.” The failure to benefit the millions of small- to medium-scale users of land, despite the rhetoric of land investors, major donors such as the finance arms of the World Bank Group, and governments facilitating the deals, has emerged as a key problem in light of deepening poverty, and a dearth of sufficient employment to absorb the young population, let alone people “exiting” from the land. Numerous experts conclude that a continued rapid alienation of land, especially to large-scale investors, will exacerbate localized land scarcity, restrict the potential of smallholder-led development, and put unrealistic pressure on the non-farm economy to absorb Africa’s rapidly rising labor force.

COVID-19 Pandemic: Experiences in China and Implications for its Prevention and Treatment Worldwide

2020 ◽  
Vol 20 (6) ◽  
pp. 410-416 ◽  
Author(s):  
Ning-Ning Liu ◽  
Jing-Cong Tan ◽  
Jingquan Li ◽  
Shenghui Li ◽  
Yong Cai ◽  
...  
Keyword(s):  
Clinical Characteristics ◽  
International Community ◽  
Disease Spread ◽  
Global Dynamics ◽  
The World ◽  
Prevention And Treatment ◽  
History Of

The outbreak of COVID-19 due to SARS-CoV-2 originally emerged in Wuhan in December 2019. As of March 22, 2020, the disease spread to 186 countries, with at least 305,275 confirmed cases. Although there has been a decline in the spread of the disease in China, the prevalence of COVID-19 around the world remains serious despite containment efforts undertaken by national authorities and the international community. In this article, we systematically review the brief history of COVID-19 and its epidemic and clinical characteristics, highlighting the strategies used to control and prevent the disease in China, which may help other countries respond to the outbreak. This pandemic emphasizes the need to be constantly alert to shifts in both the global dynamics and the contexts of individual countries, making sure that all are aware of which approaches are successful for the prevention, containment and treatment of new diseases, and being flexible enough to adapt the responses accordingly.

The Dynamics of Society-in-the-Self

2018 ◽  
Author(s):  
Hubert J. M Hermans
Keyword(s):  
Social Environment ◽  
The Self ◽  
Boundary Crossing ◽  
The World ◽  
Self And Identity ◽  
New Vision ◽  
New Phenomena ◽  
The Relationship

In the field of tension between globalization and localization, a set of new phenomena is emerging showing that society is not simply a social environment of self and identity but works in their deepest regions: self-radicalization, self-government, self-cure, self-nationalization, self-internationalization, and even self-marriage. The consequence is that the self is faced with an unprecedented density of self-parts, called I-positions in this theory. In the field of tension between boundary-crossing developments in the world and the search for an identity in a local niche, a self emerges that is characterized by a great variety of contradicting and heterogeneous I-positions and by large and unexpected jumps between different positions as the result of rapid and unexpected changes in the world. The chapter argues that such developments require a new vision of the relationship between self and society.

scholarly journals Redshift-space effects in voids and their impact on cosmological tests. Part I: the void size function

2020 ◽  
Vol 500 (1) ◽  
pp. 911-925
Author(s):  
Carlos M Correa ◽  
Dante J Paz ◽  
Ariel G Sánchez ◽  
Andrés N Ruiz ◽  
Nelson D Padilla ◽  
...  
Keyword(s):  
Theoretical Framework ◽  
Real Space ◽  
Global Dynamics ◽  
Void Size ◽  
Spherical Void ◽  
Cosmological Constraints ◽  
Redshift Surveys ◽  
Size Function ◽  
Expansion Effect ◽  
Space Effects

ABSTRACT Voids are promising cosmological probes. Nevertheless, every cosmological test based on voids must necessarily employ methods to identify them in redshift space. Therefore, redshift-space distortions (RSD) and the Alcock–Paczyński effect (AP) have an impact on the void identification process itself generating distortion patterns in observations. Using a spherical void finder, we developed a statistical and theoretical framework to describe physically the connection between the identification in real and redshift space. We found that redshift-space voids above the shot noise level have a unique real-space counterpart spanning the same region of space, they are systematically bigger and their centres are preferentially shifted along the line of sight. The expansion effect is a by-product of RSD induced by tracer dynamics at scales around the void radius, whereas the off-centring effect constitutes a different class of RSD induced at larger scales by the global dynamics of the whole region containing the void. The volume of voids is also altered by the fiducial cosmology assumed to measure distances, this is the AP change of volume. These three systematics have an impact on cosmological statistics. In this work, we focus on the void size function. We developed a theoretical framework to model these effects and tested it with a numerical simulation, recovering the statistical properties of the abundance of voids in real space. This description depends strongly on cosmology. Hence, we lay the foundations for improvements in current models of the abundance of voids in order to obtain unbiased cosmological constraints from redshift surveys.

Finite Element Simulation of Laser Beam Welding Induced Residual Stresses and Distortions in a T-Joint Configuration for Aeronautic Structures

2009 ◽  
Author(s):  
Muhammad Zain-ul-abdein ◽  
Daniel Ne´lias ◽  
Jean-Franc¸ois Jullien ◽  
Dominique Deloison
Keyword(s):  
Finite Element ◽  
Residual Stresses ◽  
Laser Beam ◽  
Boundary Conditions ◽  
Laser Beam Welding ◽  
Temperature Fields ◽  
Heat Transfer Analysis ◽  
Small Scale ◽  
Joint Configuration ◽  
Simulation Results

Laser beam welding has found its application in the aircraft industry for the fabrication of fuselage panels in a T-joint configuration. However, the inconveniences like distortions and residual stresses are inevitable consequences of welding. The effort is made in this work to experimentally measure and numerically simulate the distortions induced by laser beam welding of a T-joint with industrially used thermal and mechanical boundary conditions on the thin sheets of aluminium 6056-T4. Several small scale experiments were carried out with various instrumentations to establish a database necessary to verify the simulation results. Finite element (FE) simulation is performed with Abaqus and the conical heat source is programmed in FORTRAN. Heat transfer analysis is performed to achieve the required weld pool geometry and temperature fields. Mechanical analysis is then performed with industrial loading and boundary conditions so as to predict the distortion and the residual stress pattern. A good agreement is found amongst the experimental and simulation results.

From global to local and back: the ‘Third World’ concept and the new radical left in France

2017 ◽  
Vol 12 (1) ◽  
pp. 115-136 ◽  
Author(s):  
Christoph Kalter
Keyword(s):  
Cold War ◽  
Migrant Workers ◽  
Third World ◽  
Global Dynamics ◽  
The Third ◽  
The World ◽  
The Third World ◽  
The Cold War ◽  
World Concept ◽  
Radical Left

AbstractIn the second half of the twentieth century, the transnational ‘Third World’ concept defined how people all over the globe perceived the world. This article explains the concept’s extraordinary traction by looking at the interplay of local uses and global contexts through which it emerged. Focusing on the particularly relevant setting of France, it examines the term’s invention in the context of the Cold War, development thinking, and decolonization. It then analyses the reviewPartisans(founded in 1961), which galvanized a new radical left in France and provided a platform for a communication about, but also with, the Third World. Finally, it shows how the association Cedetim (founded in 1967) addressed migrant workers in France as ‘the Third World at home’. In tracing the Third World’s local–global dynamics, this article suggests a praxis-oriented approach that goes beyond famous thinkers and texts and incorporates ‘lesser’ intellectuals and non-textual aspects into a global conceptual history in action.

Psychology Within and Without the State

2021 ◽  
Vol 73 (1) ◽  
Author(s):  
H. Clark Barrett
Keyword(s):  
Indigenous Communities ◽  
Psychological Research ◽  
Social Processes ◽  
Cross Cultural ◽  
Small Scale ◽  
Annual Review ◽  
Publication Date ◽  
Social Scientists ◽  
The World ◽  
Psychological Similarity

Psychological research in small-scale societies is crucial for what it stands to tell us about human psychological diversity. However, people in these communities, typically Indigenous communities in the global South, have been underrepresented and sometimes misrepresented in psychological research. Here I discuss the promises and pitfalls of psychological research in these communities, reviewing why they have been of interest to social scientists and how cross-cultural comparisons have been used to test psychological hypotheses. I consider factors that may be undertheorized in our research, such as political and economic marginalization, and how these might influence our data and conclusions. I argue that more just and accurate representation of people from small-scale communities around the world will provide us with a fuller picture of human psychological similarity and diversity, and it will help us to better understand how this diversity is shaped by historical and social processes. Expected final online publication date for the Annual Review of Psychology, Volume 73 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Het Hoge Kempen ruraal-industrieel transitielandschap

2019 ◽  
Vol 4 (3) ◽  
pp. 194-207
Author(s):  
PIET GELEYNS
Keyword(s):  
Large Scale ◽  
Western Europe ◽  
Farming System ◽  
Small Scale ◽  
Coal Miners ◽  
Garden Cities ◽  
World Heritage List ◽  
The World ◽  
Outstanding Universal Value ◽  
Extensive Farming

The Hoge Kempen rural industrial transition landscape: a layered landscape of Outstanding Universal Value? Up until the beginning of the 20th century, the eastern part of the Belgian province of Limburg was a sparsely populated and not very productive part of the country. The dominating heathland was maintained with sheep, which were an essential part of a small-scale extensive farming system. This all changed when coal was discovered in 1901. Seven large coalmines were established in a few decades, each one employing thousands of coal-miners. This also meant that entire new garden cities were built, to house the coal-miners and their families. The confrontation between the small-scale traditional land-use and the new large-scale industrial developments defines the landscape up to today. The scale and the force of the turnover are considered unprecedented for Western Europe, which is why it is being presented by Belgium for inclusion in the World Heritage List.

Fishing for a Career: Alternative Livelihoods and the Hardheaded Art of Academic Failure

2017 ◽  
Vol 2 (2) ◽  
pp. 155-167
Author(s):  
Deb Cleland
Keyword(s):  
East Asia ◽  
Marine Ecosystem ◽  
Academic Failure ◽  
Work Life ◽  
Small Scale ◽  
South East Asia ◽  
Alternative Livelihoods ◽  
Alternative Livelihood ◽  
The World ◽  
History Of

Charting the course: The world of alternative livelihood research brings a heavy history of paternalistic colonial intervention and moralising. In particular, subsistence fishers in South East Asia are cyclical attractors of project funding to help them exit poverty and not ‘further degrade the marine ecosystem’ (Cinner et al. 2011), through leaving their boats behind and embarking on non-oceanic careers. What happens, then, when we turn an autoethnographic eye on the livelihood of the alternative livelihood researcher? What lexicons of lack and luck may we borrow from the fishers in order to ‘render articulate and more systematic those feelings of dissatisfaction’ (Young 2002) of an academic’s life’s work and our work-life? What might we learn from comparing small-scale fishers to small-scale scholars about how to successfully ‘navigate’ the casualised waters of the modern university? Does this unlikely course bring any ideas of ‘possibilities glimmering’ (Young 2002) for ‘exiting’ poverty in Academia?

INTERNATIONAL INFRASTRUCTURE AGENDA AND RUSSIA

2021 ◽  
Vol 2 (8) ◽  
pp. 106-121
Author(s):  
O. V. IVANOV ◽  
◽  
M. A. IVANOVA ◽  
M. V. TKACHENKO ◽  
◽  
...  
Keyword(s):  
Sustainable Development ◽  
Russian Federation ◽  
Infrastructure Development ◽  
High Quality ◽  
New Approaches ◽  
The World ◽  
The Russian Federation ◽  
New Phenomena ◽  
Quality Infrastructure

The new phenomena of the world infrastructure practice are analyzed in the context of the paradigm of sustainable development. Special attention is paid to the conceptual and doctrinal design of new approaches to infrastructure development – the concepts of sustainable and high-quality infrastructure, responsible in-vestment. The efforts of the Russian Federation in this area are considered through the prism of the main trends in global infrastructure development. Conclusions are drawn about the key barriers that hinder the full-fledged development of the infrastructure complex, suggestions and recommendations are made on improv-ing approaches to the infrastructure development of Russia to achieve sustainable development.

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