Errata [The periodic solution as a first approximation in the lunar theory]

1895 ◽  
Vol 15 ◽  
pp. 152
Author(s):  
G. W. Hill
Keyword(s):  
Periodic Solution ◽  
Lunar Theory ◽  
First Approximation

On nearly-commensurable periods in the restricted problem of three bodies, with calculations of the long-period variations in the interior 2:1 case

1966 ◽  
Vol 25 ◽  
pp. 197-222 ◽  
Author(s):  
P. J. Message
Keyword(s):  
Periodic Solution ◽  
Periodic Solutions ◽  
Large Amplitude ◽  
Restricted Problem ◽  
Small Amplitude ◽  
Minor Planets ◽  
Long Period ◽  
Numerical Integrations ◽  
Period Variations ◽  
The Mean

An analytical discussion of that case of motion in the restricted problem, in which the mean motions of the infinitesimal, and smaller-massed, bodies about the larger one are nearly in the ratio of two small integers displays the existence of a series of periodic solutions which, for commensurabilities of the typep+ 1:p, includes solutions of Poincaré'sdeuxième sortewhen the commensurability is very close, and of thepremière sortewhen it is less close. A linear treatment of the long-period variations of the elements, valid for motions in which the elements remain close to a particular periodic solution of this type, shows the continuity of near-commensurable motion with other motion, and some of the properties of long-period librations of small amplitude.To extend the investigation to other types of motion near commensurability, numerical integrations of the equations for the long-period variations of the elements were carried out for the 2:1 interior case (of which the planet 108 “Hecuba” is an example) to survey those motions in which the eccentricity takes values less than 0·1. An investigation of the effect of the large amplitude perturbations near commensurability on a distribution of minor planets, which is originally uniform over mean motion, shows a “draining off” effect from the vicinity of exact commensurability of a magnitude large enough to account for the observed gap in the distribution at the 2:1 commensurability.

Psychological literacy: A first approximation.

1990 ◽  
Vol 45 (7) ◽  
pp. 891-900 ◽  
Author(s):  
C. Alan Boneau
Keyword(s):  
First Approximation

Rapid evaluation of FDG imaging alternatives using head-to-head comparisons of full ring and gamma camera based PET scanners –

2002 ◽  
Vol 41 (05) ◽  
pp. 208-213 ◽  
Author(s):  
L. M. Haslinghuis-Bajan ◽  
L. Hooft ◽  
A. van Lingen ◽  
M. van Tulder ◽  
W. Devillé ◽  
...  
Keyword(s):  
Methodological Quality ◽  
Gamma Camera ◽  
First Generation ◽  
Prospective Evaluation ◽  
First Approximation ◽  
Variable Head ◽  
Malignant Lesions ◽  
The Impact ◽  
Pet Scanners

SummaryAim: While FDG full ring PET (FRPET) has been gradually accepted in oncology, the role of the cheaper gamma camera based alternatives (GCPET) is less clear. Since technology is evolving rapidly, “tracker trials” would be most helpful to provide a first approximation of the relative merits of these alternatives. As difference in scanner sensitivity is the key variable, head-to-head comparison with FRPET is an attractive study design. This systematic review summarises such studies. Methods: Nine studies were identified until July 1, 2000. Two observers assessed the methodological quality (Cochrane criteria), and extracted data. Results: The studies comprised a variety of tumours and indications. The reported GC- and FRPET agreement for detection of malignant lesions ranged from 55 to 100%, but with methodological limitations (blinding, standardisation, limited patient spectrum). Mean lesion diameter was 2.9 cm (SD 1.8), with only about 20% <1.5 cm. The 3 studies with the highest quality reported concordances of 74-79%, for the studied lesion spectrum. Contrast at GCPET was lower than that of FRPET, contrast and detection agreement were positively related. Logistic regression analysis suggested that pre-test indicators might be used to predict FRPET-GCPET concordance. Conclusion: In spite of methodological limitations, “first generation” GCPET devices detected sufficient FRPET positive lesions to allow prospective evaluation in clinical situations where the impact of FRPET is not confined to detection of small lesions (<1.5 cm). The efficiency of head-to-head comparative studies would benefit from application in a clinically relevant patient spectrum, with proper blinding and standardisation of acquisition procedures.

Wildfire risk and hazard: procedures for the first approximation

2010 ◽  
Author(s):  
David E. Calkin ◽  
Alan A. Ager ◽  
Julie Gilbertson-Day
Keyword(s):  
Wildfire Risk ◽  
First Approximation

Napfmarathon versus Stadtmarathon: Eine Annäherung an das Konzept des Leistungskilometers

2015 ◽  
Vol 63 (1) ◽  
Keyword(s):  
Accurate Estimation ◽  
Horizontal Distance ◽  
First Approximation ◽  
The City

The aim of this study was to investigate differences in course times of a mountainmarathon (Napfmarathon) versus a city Marathon. Therefore all participants of Napfmarathon were screened concerning a double participation on a city marathon (Zürich, Winterthur, Lausanne, Luzern) and the course time were compared. Of key interest was the influence of ascents and descents which were quantified according to ­guidelines of Youth & Sport (Jugend + Sport / Jeunesse et Sport), whereby in first approximation 100 meter of ascent, 150 meter of descent (more than 20%) and 1 km of horizontal distance were taken as a simallar performance correlat. For the identified double starter different average times per km resulted. For the city marathon with an average time of 4 min 52 sec and for the Napfmarathon with 4 min 28 sec. If speed per km was calculated only with ascent and horizontal distances having performance relevance an average time of 4 min 56 sec per km was identified. This effect seems to be independet from distance absolved, resulting for Halbmarathon on an average time of distance of 4 min 13 sec, for Napfmarathon of 4 min 4 sec and for the performance concept only with ascent an average time per km of 4 min 16 sec. These analysis reveal, that if only ascent is taxed average course times differ less than 5 sec for both distances. For these particular reasons we recommend for running events to calculate only based on ascent and horizontal distances making necessary adjustments based on length of course, steepness of ascent and descent, character of terain (middle-country, pre-alps, alpes) for accurate estimation of course times.

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