Limits of Stability for Planets in Double Star Systems Using the Fast Lyapunov Indicators

The risk of falling increases with age. Individuals wearing unadapted shoes present an aggravating risk factor. The objective of this study was to determine the effectiveness of specifically designed balance shoes on balance and postural stability in healthy elderly people compared to that of their usual shoes. In total, 21 healthy individuals aged 65–84 years (76.0 ± 8.0 years) performed balance tests (bipedal with open or closed eyes, unipedal with open eyes, limits of stability, and step cadence) while wearing their (i) personal shoes or (ii) balance shoes (Axis Comfort Development©). Three test sessions were conducted with personal and balance shoes. The first served as the baseline, and the other two were performed after a familiarization period of several days with the personal or balance shoes. The perception of balance shoe efficiency was documented using a questionnaire. The balance shoes significantly improved bipedal balance with closed eyes. Moreover, the familiarization period significantly improved unipedal balance with open eyes. Most subjects felt safer and stabler using balance shoes. The investigated specifically designed balance shoes were effective in elderly individuals in improving postural balance compared to personal shoes. The balance shoes could, therefore, reduce the falling risk in healthy elderly people.

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A Plan for a New Generation 2 m-Class Telescope in Indonesia

International Astronomical Union Colloquium ◽

10.1017/s0252921100088758 ◽

1984 ◽

Vol 80 ◽

pp. 409-410

Author(s):

Karel A. Van Der Hucht

Keyword(s):

Double Star ◽

Radial Velocities ◽

Spectroscopic Binaries ◽

Theoretical Research ◽

60Th Anniversary ◽

Additional Tool ◽

New Generation

AbstractOne of the prime astrophysical interests of the Observatorium Bosscha is, and has always been, double star research: visual double star research with the double-60 cm Zeiss telescope (dedicated in 1928), and theoretical research of evolved massive spectroscopic binaries (since 1972). For one thing, this is the very reason that this IAU Colloquium No. 80, celebrating the 60th anniversary of the Observatorium Bosscha in Lembang, is devoted to binary astrophysics.Up to now, visual, photographic, and photometric tools have been used for binary research at the Observatorium Bosscha. An important, essential additional tool for binary research is spectrographic equipment, in order to measure radial velocities of binary components.

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SUSI’s Potential for Double Star Research

International Astronomical Union Colloquium ◽

10.1017/s0252921100007041 ◽

1992 ◽

Vol 135 ◽

pp. 521-526

Author(s):

John Davis

Keyword(s):

Angular Resolution ◽

Double Star ◽

Double Stars ◽

Stellar Interferometer ◽

New Instrument

AbstractThe Sydney University Stellar Interferometer (SUSI) is currently undergoing commissioning and will soon commence its astronomical program in which observations of double stars will form a major component. With its 640-m long North–South array of input siderostats, the new instrument will have unprecedented angular resolution.

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Radial variation of whistler-mode chorus: first results from the STAFF/DWP instrument on board the Double Star TC-1 spacecraft

Annales Geophysicae ◽

10.5194/angeo-23-2937-2005 ◽

2005 ◽

Vol 23 (8) ◽

pp. 2937-2942 ◽

Cited By ~ 45

Author(s):

O. Santolík ◽

E. Macúšová ◽

K. H. Yearby ◽

N. Cornilleau-Wehrlin ◽

H. StC. K. Alleyne

Keyword(s):

Cyclotron Frequency ◽

Power Spectra ◽

Double Star ◽

Electron Cyclotron ◽

Radial Variation ◽

Whistler Mode ◽

Electron Cyclotron Frequency ◽

The Earth ◽

First Results ◽

Initial Results

Abstract. We use the first measurements of the STAFF/DWP instrument on the Double Star TC-1 spacecraft to investigate whistler-mode chorus. We present initial results of a systematic study on radial variation of dawn chorus. The chorus events show an increased intensity at L parameter above 6. This is important for the possible explanation of intensifications of chorus, which were previously observed closer to the Earth at higher latitudes. Our results also indicate that the upper band of chorus at frequencies above one-half of the electron cyclotron frequency disappears for L above 8. The lower band of chorus is observed at frequencies below 0.4 of the electron cyclotron frequency up to L of 11-12. The maxima of the chorus power spectra are found at slightly lower frequencies compared to previous studies. We do not observe any distinct evolution of the position of the chorus frequency band as a function of L. More data of the TC-1 spacecraft are needed to verify these initial results and to increase the MLT coverage.

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