scholarly journals Relativistic aspects of rotational motion of celestial bodies

2009 ◽  
Vol 5 (S261) ◽  
pp. 112-123 ◽  
Author(s):  
S. A. Klioner ◽  
E. Gerlach ◽  
M. H. Soffel
Keyword(s):  
High Precision ◽  
Rotational Motion ◽  
Earth Rotation ◽  
Theoretical Framework ◽  
Reference Systems ◽  
The Moon ◽  
Newtonian Theory ◽  
Recent Developments ◽  
Celestial Bodies ◽  
Near Future

AbstractRelativistic modelling of rotational motion of extended bodies represents one of the most complicated problems of Applied Relativity. The relativistic reference systems of IAU (2000) give a suitable theoretical framework for such a modelling. Recent developments in the post-Newtonian theory of Earth rotation in the limit of rigidly rotating multipoles are reported below. All components of the theory are summarized and the results are demonstrated. The experience with the relativistic Earth rotation theory can be directly applied to model the rotational motion of other celestial bodies. The high-precision theories of rotation of the Moon, Mars and Mercury can be expected to be of interest in the near future.

scholarly journals Rers2014 and Mrs2014: New High-Precision Rigid Earth Rotation and Moon Rotation Series

2015 ◽  
Vol 50 (1) ◽  
pp. 35-40
Author(s):  
V.V. Pashkevich
Keyword(s):  
Numerical Solution ◽  
Numerical Investigation ◽  
High Precision ◽  
Rotational Motion ◽  
Earth Rotation ◽  
Euler Angles ◽  
Time Intervals ◽  
The Earth ◽  
Long Time ◽  
Rigid Earth

Abstract Numerical investigation of the Earth and Moon rotational motion dynamics is carried out at a long time intervals. In our previous studies (Pashkevich, 2013), (Pashkevich and Eroshkin, 2011) the high-precision Rigid Earth Rotation Series (designated RERS2013) and Moon Rotation Series (designated MRS2011) were constructed. RERS2013 are dynamically adequate to the JPL DE422/LE422 (Folkner, 2011) ephemeris over 2000 and 6000 years and include about 4113 periodical terms (without attempt to estimate new subdiurnal and diurnal periodical terms). MRS2011 are dynamically adequate to the JPL DE406/LE406 (Standish, 1998) ephemeris over 418, 2000 and 6000 years and include about 1520 periodical terms. In present research have been improved the Rigid Earth Rotation Series RERS2013 and Moon Rotation Series MRS2011, and as a result have been constructed the new high-precision Rigid Earth Rotation Series RERS2014 and Moon Rotation Series MRS2014 dynamically adequate to the JPL DE422/LE422 ephemeris over 2000 and 6000 years, respectively. The elaboration of RERS2013 is carried out by means recalculation of sub-diurnal and diurnal periodical terms. The residuals in Euler angles between the numerical solution and RERS2014 do not surpass 3 ìas over 2000 years. Improve the accuracy of the series MRS2011 is obtained by using the JPL DE422/LE422 ephemeris. The residuals in the perturbing terms of the physical librations between the numerical solution and MRS2014 do not surpass 8 arc seconds over 6000 years

scholarly journals Relativistic Considerations for Precession and Nutation

1998 ◽  
Vol 11 (1) ◽  
pp. 173-176
Author(s):  
S.A. Klioner ◽  
M. Soffel
Keyword(s):  
General Relativity ◽  
Rotational Motion ◽  
Earth Rotation ◽  
Equations Of Motion ◽  
Relativistic Effects ◽  
Point Of View ◽  
Extended Body ◽  
The Earth ◽  
Celestial Bodies

Abstract The whole scope of problems related with the rotational motion of celestial bodies is briefly discussed. Relativistic modeling of the Earth rotation is considered from a conceptual point of view. Relativistic effects in rotational equations of motion of an extended body in general relativity are discussed. Numerical values of the effects are given.

Recent developments in automated Transmission Electron MI

1989 ◽  
Vol 47 ◽  
pp. 46-47
Author(s):  
W.J. de Ruijter ◽  
P. Rez ◽  
David J. Smith
Keyword(s):  
Image Analysis ◽  
Computer Image ◽  
Lens Design ◽  
Computer Image Analysis ◽  
Transmission Electron ◽  
Resolution Electron ◽  
Recent Developments ◽  
On Line ◽  
Routine Procedures ◽  
Near Future

There is growing interest in the on-line use of computers in high-resolution electron n which should reduce the demands on highly skilled operators and thereby extend the r of the technique. An on-line computer could obviously perform routine procedures hand, or else facilitate automation of various restoration, reconstruction and enhan These techniques are slow and cumbersome at present because of the need for cai micrographs and off-line processing. In low resolution microscopy (most biologic; primary incentive for automation and computer image analysis is to create a instrument, with standard programmed procedures. In HREM (materials researc computer image analysis should lead to better utilization of the microscope. Instru (improved lens design and higher accelerating voltages) have improved the interpretab the level of atomic dimensions (approximately 1.6 Å) and instrumental resolutior should become feasible in the near future.

Modelling Lunar Extremes

2018 ◽  
Vol 3 (2) ◽  
pp. 207-216 ◽  
Author(s):  
David Fisher ◽  
Lionel Sims
Keyword(s):  
High Precision ◽  
Celestial Mechanics ◽  
Computer Modelling ◽  
Landscape Context ◽  
The Sun ◽  
The Moon

Claims first made over half a century ago that certain prehistoric monuments utilised high-precision alignments on the horizon risings and settings of the Sun and the Moon have recently resurfaced. While archaeoastronomy early on retreated from these claims, as a way to preserve the discipline in an academic boundary dispute, it did so without a rigorous examination of Thom’s concept of a “lunar standstill”. Gough’s uncritical resurrection of Thom’s usage of the term provides a long-overdue opportunity for the discipline to correct this slippage. Gough (2013), in keeping with Thom (1971), claims that certain standing stones and short stone rows point to distant horizon features which allow high-precision alignments on the risings and settings of the Sun and the Moon dating from about 1700 BC. To assist archaeoastronomy in breaking out of its interpretive rut and from “going round in circles” (Ruggles 2011), this paper evaluates the validity of this claim. Through computer modelling, the celestial mechanics of horizon alignments are here explored in their landscape context with a view to testing the very possibility of high-precision alignments to the lunar extremes. It is found that, due to the motion of the Moon on the horizon, only low-precision alignments are feasible, which would seem to indicate that the properties of lunar standstills could not have included high-precision markers for prehistoric megalith builders.

Organic Reactivity Control by Means of Neighboring Groups and Organometallics. A Personal Account

1994 ◽  
Vol 59 (1) ◽  
pp. 1-74 ◽  
Author(s):  
Pavel Kočovský
Keyword(s):  
Transition Metals ◽  
Cyclopropane Ring ◽  
Allylic Substitutions ◽  
Recent Developments ◽  
Cardioactive Drug ◽  
Novel Method ◽  
Metal Catalyzed ◽  
Electrophilic Additions ◽  
Near Future ◽  
First Time

This review summarizes the main topics of our research and covers the period of the last 15 years. The prime interest is focused on various ways of controlling the regio- and stereoselectivity of selected organic reactions, in particular electrophilic additions, cleavage of cyclopropane rings, and allylic substitutions by means of neighboring groups and/or transition and non-transition metals. In the first part, the factors governing the course of electrophilic additions are assessed, culminating in the formulation of selection rules for the reactivity of cyclohexene systems, and in a concise synthesis of the natural cardioactive drug, strophanthidin. These studies also contribute to a better understanding of the mechanisms of electrophilic additions. The second part describes recent developments in the stereo- and regiocontrolled cleavage of cyclopropane rings by non-transition metals (Tl and Hg), and the reactivity and transmetalation (with Pd) of the primary products. This methodology has resulted in novel routes to unique polycyclic structures, and will have synthetic applications in the near future. Evidence for the stereospecific "corner" cleavage of the cyclopropane ring has been provided for the first time for Tl and later for Hg. The third part deals with transition metal-catalyzed allylic substitution. Evidence for a new "syn" mechanism for the formation of the intermediate (π-allyl)palladium complex has been provided, which runs counter to the generally accepted "anti" mechanism. A novel method for a Pd-catalyzed allylic oxidation has been developed and employed in the synthesis of natural sesquiterpenes. The increasing importance of transition and non-transition metals for synthetic organic chemistry is demonstrated by their unique reactivity in a number of the papers included in this review.

Milton in China ‘Yet Once More’

2017 ◽  
Author(s):  
Bing Yan
Keyword(s):  
Literary Criticism ◽  
World Literature ◽  
Paradise Lost ◽  
Subsequent Discussion ◽  
Recent Developments ◽  
Collaborative Context ◽  
Chinese Literary Criticism ◽  
Near Future

This chapter overviews Chinese reception of Milton, with an emphasis on some of the most well-known Chinese translations of Paradise Lost. Close readings of these translations against Milton’s original demonstrate the difficulties of and resolutions for rendering Milton’s verse specific to Chinese. The subsequent discussion of the paratexts accompanying Chinese translations and of ‘introduction to world literature’ series gives a sense of the collaborative context that has shaped and continues to shape today’s general reception of Milton in China. That politically charged reception, eager to view Milton’s Satan as the embodiment of the poet’s revolutionary spirit, also dominates some recent works of Chinese literary criticism. The chapter ends by conceding that, while Milton scholarship in China has been relatively univocal and is still young, recent developments in world literature promise that innovative and intriguing work on Milton can be expected from China in the near future.

scholarly journals Negativity and Political Behavior: A Theoretical Framework for the Analysis of Negative Voting in Contemporary Democracies

2021 ◽  
pp. 147892992110001
Author(s):  
Diego Garzia ◽  
Frederico Ferreira da Silva
Keyword(s):  
Public Opinion ◽  
Political Behavior ◽  
Voting Behavior ◽  
Theoretical Framework ◽  
Negative Attitudes ◽  
Affective Component ◽  
Parliamentary Systems ◽  
Recent Developments ◽  
Rational Component

Recent developments in Western societies have motivated a growing consideration of the role of negativity in public opinion and political behavior research. In this article, we review the scant (and largely disconnected) scientific literature on negativity and political behavior, merging contributions from social psychology, public opinion, and electoral research, with a view on developing an integrated theoretical framework for the study of negative voting in contemporary democracies. We highlight that the tendency toward negative voting is driven by three partly overlapping components, namely, (1) an instrumental–rational component characterized by retrospective performance evaluations and rationalization mechanisms, (2) an ideological component grounded on long-lasting political identities, and (3) an affective component, motivated by (negative) attitudes toward parties and candidates. By blueprinting the systematic relationships between negative voting and each of these components in turn, and suggesting multiple research paths, this article aims to stimulate future studies on negative voting in multi-party parliamentary systems to motivate a better understanding of the implications of negativity in voting behavior in contemporary democracies.

Cold atom interferometry for inertial sensing in the field

2020 ◽  
Vol 9 (5) ◽  
pp. 221-225
Author(s):  
Ravi Kumar ◽  
Ana Rakonjac
Keyword(s):  
High Precision ◽  
Cold Atoms ◽  
Cold Atom ◽  
Atom Interferometry ◽  
Precision Measurements ◽  
Inertial Sensing ◽  
Fundamental Physics ◽  
Recent Developments ◽  
Resource Exploration ◽  
Atom Interferometers

AbstractAtom interferometry is one of the most promising technologies for high precision measurements. It has the potential to revolutionise many different sectors, such as navigation and positioning, resource exploration, geophysical studies, and fundamental physics. After decades of research in the field of cold atoms, the technology has reached a stage where commercialisation of cold atom interferometers has become possible. This article describes recent developments, challenges, and prospects for quantum sensors for inertial sensing based on cold atom interferometry techniques.

Sign in / Sign up

Export Citation Format

Share Document