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Dr. K. Whybrew J. K. Raine G. R. Dunlop H. Overbye 《The International Journal of Advanced Manufacturing Technology》1993,8(2):111-113
An articulated geometry which overcomes the problem of loss of traction in differentially steered skid tractor automatic guided vehicles is described. 相似文献
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The concept of Motif Combination was introduced in the French Automotive industry's R&W standard. There has however been no formal mathematical theory for the technique of motif combination. This paper sets out to develop this theory. The main result of the paper is a set of four properties that the motif combination rules must satisfy in order to have certain desirable metrological properties.Motif methods may well provide useful techniques which complement rather than replace the traditional approach based on a mean line. It was found that many functional problems could be simulated very efficiently using motif methods. Examples of functional simulation via motif combination are illustrated in the paper. 相似文献
178.
Diane M. Moran F. S. Richardson
M. Koralewski
B. M. Wanklyn
《Journal of Alloys and Compounds》1992,180(1-2):171-175Chiroptical luminescence and circular dichroism measurements are reported for single crystals of Ho2Ge2O7. These crystals belong to the tetragonal space group P4,2,2 (or P43212) with Z=4. Each Ho3+ ion in the crystal structure is coordinated to seven oxygens to form a distorted pentagonal bipyramid. The Ho3+ ions exhibit luminescence from several excited multiplet levels; chiroptical luminescence spectra are reported for 6I8 → 6F6, 6S2, and 6F3 at a sample temperature of 10 K. Room-temperature absorption and circular dichroism measurements are reported for the 6I8 → 6F6, 5S2, 6F4, and 6F3 transition regions. 相似文献
179.
T. Jing M. Sc. Ir. P. H. F. Moshuis Prof. Dr. Ir. F. H. Kreuger 《Electrical Engineering (Archiv fur Elektrotechnik)》1991,74(4):315-319
Contents Surface charge accumulation and its decay at a GIS spacer are studied at atmospheric conditions employing a two step-calibration method. The results show that the accumulation saturates within 30 minutes; the dominant mechanism of surface charge accumulation is the drift of charged particles via air, while that of the decay is surface conduction. The characteristics are similar at both polarities.
Sättigungskonzentration und Abklingverhalten der Oberflächenladung an einem mit Gleichspannung beanspruchten Abstandshalter unter atmosphärischen Bedingungen
Übersicht Die Konzentration und das Abklingen von Oberflächenladungen an einem GIS Abstandshalter wurden unter atmosphärischen Bedingungen mit Hilfe eines zweistufigen Kalibrierungsverfahrens untersucht. Die Ergebnisse zeigen eine Sättigung der Ladungskonzentration innerhalb von 30 Minuten. Als Hauptursache der Ladungskonzentration ist die Drift geladener Teilchen in Luft anzusehen, während das Abklingen auf die Oberflächenleitung zurückzuführen ist. Ähnliche Charakteristiken ergeben sich mit beiden Polaritäten.相似文献
180.
Fleming Alison S.; Ruble Diane N.; Flett Gordon L.; Shaul David L. 《Canadian Metallurgical Quarterly》1988,24(1):71
Self-report data were obtained from a middle-income sample of first-time mothers during pregnancy and at 1 and 3 months postpartum, and behavioral interactions between the mother and her infant were observed at 3 days and 1, 3, and 16 months postpartum. The main analyses revealed that pregnancy and postpartum mood states together explain a high proportion of the variance in mothers' maternal attitudes during the postpartum, although postpartum mood has the greater predictive power. Additionally, prior experience with children is significantly associated with maternal attitudes at all time points. Moreover, at both 1 and 3 months postpartum, depressed mothers, relative to nondepressed mothers, exhibit fewer affectionate contact behaviors toward their infants and are less likely to respond to infant vocalizations by vocalizing themselves, and, at 3 months, a higher proportion of the depressed mothers had started bottle-feeding their infants. Finally, differences in maternal behavior between depressed and nondepressed mothers during the early postpartum period were no longer apparent at 16 months postpartum. The implications of these findings are discussed with particular reference to the interrelations between prior child-care experience, mood, and maternal responsiveness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献