Selection of the Time Parameters of Oscillating Impulse Voltages for On-Site Testing of Gas Insulated Switchgears (GIS)

1985 ◽  
Vol 25 (4) ◽  
pp. 329-335 ◽  
Author(s):  
W. Hauschild ◽  
W. Schader ◽  
W. Mosch ◽  
K. Petzold
1998 ◽  
Vol 4 (6) ◽  
pp. 653-666 ◽  
Author(s):  
J. Delgado Rodrigues ◽  
A.P. Ferreiro Pinto ◽  
A.E. Charola ◽  
L. Aires-Barros ◽  
F.M.A. Henriques

Abstract During the exterior conservation project of the Tower of Belem, Lisbon, it was noticed that although most of the Lioz limestone used in its construction was in good condition, some specific areas presented severe powdering and flaking deterioration patterns. These are mainly due to the effect of natural weathering, including anthropogenic air-pollution, on poorer quality Lioz limestone. Since the deterioration affects mainly the immediate surface and subsurface of the stone blocks, the application of stone consolidants was considered as the most appropriate solution for this problem. This paper describes the difficulties encountered in the evaluation of the tested consolidants-an ethyl silicate ester, an acrylic resin and an epoxy resin-applied in situ. The laboratory and on-site testing used in the final selection are described as well as the actual approach to consolidating the different areas that required this treatment.


2013 ◽  
Vol 20 (1) ◽  
pp. 87-98 ◽  
Author(s):  
Wiesław Miczulski ◽  
Piotr Powroźnik

Abstract The paper presents a new elastic scheduling task model which has been used in the uniprocessor node of a control measuring system. This model allows the selection of a new set of periods for the occurrence of tasks executed in the node of a system in the case when it is necessary to perform additional aperiodic tasks or there is a need to change the time parameters of existing tasks. Selection of periods is performed by heuristic algorithms. This paper presents the results of the experimental use of an elastic scheduling model with a GRASP heuristic algorithm.


2001 ◽  
Vol 196 ◽  
pp. 170-172 ◽  
Author(s):  
François R. Querci ◽  
Monique Querci

The archives of meteorological satellites allow pre-selection of dry sites well adapted to astronomical observations (in the visible, infrared and millimetric ranges). The GSM (Grating Scale Monitor) technique then permits qualification of them as sites for future astronomical observatories. Such sites are found in new astronomical countries or in developing countries. At the same time, their protection from light pollution and/or radio interference has to be secured. In practice, once pre-selections are made, the governments of these countries ought to be alerted, for example by the IAU and/or the UN Office for Outer Space Affairs. The local site testing through GSM should be carried out in cooperation with scientists of these countries under the umbrella of the IAU. This could be an approach to help introduce astronomy and astrophysics into developing countries.


1984 ◽  
Vol 79 ◽  
pp. 191-201 ◽  
Author(s):  
F. Roddier

Since a lot of efforts and money are being put in building larger telescopes, astronomers are becoming more concern with the effects of “atmospheric seeing” on astronomical observations. Observers need to correct their observations for image degradation and put more and more emphasis on the importance of good seeing conditions. Both observers and optical engineers try to compare the image quality between different telescopes and sites. In addition, engineers are interested in locating the origin of image degradation. What are the relative contributions of the dome and of the free atmosphere to image degradation ? As engineers become able to reduce dome seeing, the selection of a good astronomical site becomes more crucial and reliable methods for site testing become necessary.


2009 ◽  
Vol 5 (S261) ◽  
pp. 50-55 ◽  
Author(s):  
V. E. Zharov ◽  
M. V. Sazhin ◽  
V. N. Sementsov ◽  
K. V. Kuimov ◽  
O. S. Sazhina ◽  
...  

AbstractTime series of the coordinates of the ICRF radio sources were analyzed. It was shown that part of radio sources, including even the so-called “defining” sources, show a the significant apparent motion. Corrections for their a priori coordinates are time functions. The celestial reference frame stability is provided by the no-net-rotation condition applied to the selected subset of sources, which leads in our case to a rotation of the frame axes with time. Parameters of this rotation were calculated for different subsets of sources.To improve stability of the celestial reference frame new methods of selection of the extragalactic radio sources were suggested. The first one was called “cosmological” and the second one “kinematical”. It was shown that a selected subset of the ICRF sources, according to cosmological criteria, determines the most stable coordinate system during next decade.


2017 ◽  
Vol 8 ◽  
pp. 37-44
Author(s):  
HANDAJI NAJAT, HAMID BENYAHIA ◽  
NAJAT ARSALANE, HASSAN BENAOUDA

Morocco is one of the major exporters of small citrus fruits, such as mandarin and Clementine. Seedlessness is a major criterion for this horticultural group. The present study focused on the selection of the best triploid mandarin hybrids (2n=3x=27) characterized by seedless fruits. A series of crosses between ‘Sidi Aissa’ clementine (female parent) and seven mandarin varieties (‘Lee’, ‘Wilking’, ‘Osceola’, ‘Carvalhal’, ‘Satsuma Frost’, ‘Satsuma Owari’ and ‘Chienka’) was performed by the National Institute for Agricultural Research. Forty triploid mandarins were obtained and planted since 2002 in an experimental field at El Menzeh. Varietal evaluation was focusing on fruit quality traits during seven years. Statistical analyzes showed that there is a significant difference for all studied characters and between hybrids. The number of seeds per fruit is the main criterion which differentiates between triploids mandarin’s hybrids and their diploid parent “clementine Sidi Aissa”. The best hybrids selected were: HT11, HT13, HT27, HT43, HT44, and HT49. The best crosses are C1 (‘Sidi Aissa’ × ‘Wilking’) andC2 (‘Sidi Aissa’ בOsceola’). These promising triploid hybrids of mandarin have been multiplied on several rootstock trials and are in the process of quantitative evaluation and multi-site testing.


Author(s):  
Shashank Sharma ◽  
Anurag Purwar ◽  
Q. Jeffrey Ge

Fourier descriptor (FD)-based path synthesis algorithms for generation of planar four-bar mechanisms require assigning time parameter values to the given points along the path. An improper selection of time parameters leads to poor fitting of the given path and suboptimal four-bar mechanisms while also ignoring a host of mechanisms that could be potentially generated otherwise. A common approach taken is to use uniform time parameter values, which does not take into account the unique harmonic properties of the coupler path. In this paper, we are presenting a nonuniform parametrization scheme in conjunction with an objective function that provides a better fit, leverages the harmonics of the four-bar coupler, and allows imposing additional user-specified constraints.


2017 ◽  
Vol 23 (2) ◽  
pp. 5
Author(s):  
Erick Meza ◽  
Antonio Pereyra ◽  
Bruno Sicardy ◽  
Germán Comina ◽  
José Ishitsuka

Mostramos la implementación de un instrumento de medición de la calidad de cielo (seeing) basado en la técnica del Monitoreo del Movimiento Diferencial de Imagen (DIMM). Este instrumento permite la medición precisa y sistemática del seeing, así como su evolución temporal. Fue monitoreado el seeing en el Observatorio de Huancayo durante siete noches consecutivas de Agosto de 2012. El seeing promedio fue de 1.34” ± 0 .33”.En 14% del tiempo observado el seeing estuvo por debajo de 1”, y en 71% del tiempo, por debajo de 1.5”. El dominio de la técnica y su aplicabilidad nos permitirá usar el instrumento en varios lugares donde campañas de medición de seeing sean programadas dentro del Perú. La selección de una facilidad astronómica óptica profesional (observatorio astronómico), será favorecida con medidas DIMM futuras. Palabras clave.-Medición de la calidad de cielo, Diferencial de imagen (DIMM), Observatorio de Huancayo. ABSTRACTWe show the implementation of an instrument to measure the sky quality for astronomical purposes (seeing) using the Differential Image Motion Monitor technique. This instrument let us an acute and systematic measurement of seeing along with its temporal evolution. We monitored seeing at Huancayo Observatory during seven consecutive nights in 2012 August. Mean seeing was 1.34” ± 0.33”. In 14% of the observed time, seeing was below than 1”, and in 71% below than 1.5”. The successful implementation of this technique and its applicability let us using this instrument in several places where a program of site testing will be scheduled in Peru. The selection of a professional astronomical facility (as an astronomical observatory) will be benefited with DIMM measurements. Keywords.-Measuring qualityofsky, Differential Image (DIMM), Huancayo observatory.


2019 ◽  
Vol 42 ◽  
Author(s):  
Gian Domenico Iannetti ◽  
Giorgio Vallortigara

Abstract Some of the foundations of Heyes’ radical reasoning seem to be based on a fractional selection of available evidence. Using an ethological perspective, we argue against Heyes’ rapid dismissal of innate cognitive instincts. Heyes’ use of fMRI studies of literacy to claim that culture assembles pieces of mental technology seems an example of incorrect reverse inferences and overlap theories pervasive in cognitive neuroscience.


Sign in / Sign up

Export Citation Format

Share Document