scholarly journals DETERMINATION OF SHIPBOARD CABLES PARAMETERS FOR CALCULATING THE PULSE NOISE PROPAGATION AND CALCULATION ACCURACY ESTIMATION

Author(s):  
Mikhail A. Akhrestin ◽  
◽  
Alexander A. Vorshevsky ◽  
Petr A. Vorshevsky ◽  
◽  
...  
1973 ◽  
Vol 56 (1) ◽  
pp. 213-218
Author(s):  
Edmond J Baratta ◽  
F E Knowles

Abstract A method for the determination of strontium-89 and strontium-90 in milk, involving ion exchange and purification with nitric acid, was evaluated by 11 collaborators. The accuracy of the method for strontium-89 ranged from 2 to 56% and the within-laboratory precision ranged from 11 to 76% for a concentration range of 68–480 pCi/L; values for strontium-90 in a concentration range of 50.2–116.2 pCi/L were 6.4 to 10 and 4 to 11%, respectively. The slight bias on the high side for strontium-90 was not considered serious. The collaborators had difficulty with strontium-89 analyses, as shown by the high precision and accuracy estimation values.


2018 ◽  
Vol 9 ◽  
pp. 69-74
Author(s):  
Anatoliy Tserklevich ◽  
Vasyl Khoptar

The presence of a large number of territorial units with a high price of land determines the appropriate accuracy of their area determination in the short term. The widespread use of unmanned aerial vehicles (UAVs) is a modern geospatial mapping technology. Using an UAV equipped with appropriate devices for aerosurveying  such as, for example, the Trimble UX5  is economically feasible in comparison with ground geodetic measurements, since the latter requires a lot of costs. Therefore, the main purpose of this study is to analyze accuracy estimation of land parcel area determination based on aero surveying materials using an unmanned aerial vehicle (UAV) in comparison with results of ground geodetic measurements using a total station. As a result, a comparison of detailed plan and an existing base of land parcel measurements with accuracy estimations have been made. Based on our analysis and experimental studies, we can state that the UAV allows more efficient data collection within the requirements of land management in comparison with ground geodetic measurements. The use of aero surveying materials for determination of land parcel areas has been proposed. The results of the study provide an opportunity to improve the reliability of land parcel data in the normative and methodological framework.


1966 ◽  
Vol 25 ◽  
pp. 93-97
Author(s):  
Richard Woolley

It is now possible to determine proper motions of high-velocity objects in such a way as to obtain with some accuracy the velocity vector relevant to the Sun. If a potential field of the Galaxy is assumed, one can compute an actual orbit. A determination of the velocity of the globular clusterωCentauri has recently been completed at Greenwich, and it is found that the orbit is strongly retrograde in the Galaxy. Similar calculations may be made, though with less certainty, in the case of RR Lyrae variable stars.


1999 ◽  
Vol 190 ◽  
pp. 549-554
Author(s):  
Nino Panagia

Using the new reductions of the IUE light curves by Sonneborn et al. (1997) and an extensive set of HST images of SN 1987A we have repeated and improved Panagia et al. (1991) analysis to obtain a better determination of the distance to the supernova. In this way we have derived an absolute size of the ringRabs= (6.23 ± 0.08) x 1017cm and an angular sizeR″ = 808 ± 17 mas, which give a distance to the supernovad(SN1987A) = 51.4 ± 1.2 kpc and a distance modulusm–M(SN1987A) = 18.55 ± 0.05. Allowing for a displacement of SN 1987A position relative to the LMC center, the distance to the barycenter of the Large Magellanic Cloud is also estimated to bed(LMC) = 52.0±1.3 kpc, which corresponds to a distance modulus ofm–M(LMC) = 18.58±0.05.


1961 ◽  
Vol 13 ◽  
pp. 29-41
Author(s):  
Wm. Markowitz
Keyword(s):  

A symposium on the future of the International Latitude Service (I. L. S.) is to be held in Helsinki in July 1960. My report for the symposium consists of two parts. Part I, denoded (Mk I) was published [1] earlier in 1960 under the title “Latitude and Longitude, and the Secular Motion of the Pole”. Part II is the present paper, denoded (Mk II).


1972 ◽  
Vol 1 ◽  
pp. 27-38
Author(s):  
J. Hers

In South Africa the modern outlook towards time may be said to have started in 1948. Both the two major observatories, The Royal Observatory in Cape Town and the Union Observatory (now known as the Republic Observatory) in Johannesburg had, of course, been involved in the astronomical determination of time almost from their inception, and the Johannesburg Observatory has been responsible for the official time of South Africa since 1908. However the pendulum clocks then in use could not be relied on to provide an accuracy better than about 1/10 second, which was of the same order as that of the astronomical observations. It is doubtful if much use was made of even this limited accuracy outside the two observatories, and although there may – occasionally have been a demand for more accurate time, it was certainly not voiced.


2000 ◽  
Vol 179 ◽  
pp. 205-208
Author(s):  
Pavel Ambrož ◽  
Alfred Schroll

AbstractPrecise measurements of heliographic position of solar filaments were used for determination of the proper motion of solar filaments on the time-scale of days. The filaments have a tendency to make a shaking or waving of the external structure and to make a general movement of whole filament body, coinciding with the transport of the magnetic flux in the photosphere. The velocity scatter of individual measured points is about one order higher than the accuracy of measurements.


1975 ◽  
Vol 26 ◽  
pp. 341-380 ◽  
Author(s):  
R. J. Anderle ◽  
M. C. Tanenbaum

AbstractObservations of artificial earth satellites provide a means of establishing an.origin, orientation, scale and control points for a coordinate system. Neither existing data nor future data are likely to provide significant information on the .001 angle between the axis of angular momentum and axis of rotation. Existing data have provided data to about .01 accuracy on the pole position and to possibly a meter on the origin of the system and for control points. The longitude origin is essentially arbitrary. While these accuracies permit acquisition of useful data on tides and polar motion through dynamio analyses, they are inadequate for determination of crustal motion or significant improvement in polar motion. The limitations arise from gravity, drag and radiation forces on the satellites as well as from instrument errors. Improvements in laser equipment and the launch of the dense LAGEOS satellite in an orbit high enough to suppress significant gravity and drag errors will permit determination of crustal motion and more accurate, higher frequency, polar motion. However, the reference frame for the results is likely to be an average reference frame defined by the observing stations, resulting in significant corrections to be determined for effects of changes in station configuration and data losses.


1979 ◽  
Vol 44 ◽  
pp. 349-355
Author(s):  
R.W. Milkey

The focus of discussion in Working Group 3 was on the Thermodynamic Properties as determined spectroscopically, including the observational techniques and the theoretical modeling of physical processes responsible for the emission spectrum. Recent advances in observational techniques and theoretical concepts make this discussion particularly timely. It is wise to remember that the determination of thermodynamic parameters is not an end in itself and that these are interesting chiefly for what they can tell us about the energetics and mass transport in prominences.


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