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991.
A. I. Gorelov A. I. Efanov V. G. Nazaryan V. V. Postnikov A. N. Sviridenkov V. V. Shevchenko 《Atomic Energy》1989,66(2):90-96
Translated from Atomnaya Énergiya, Vol. 66, No. 2, pp. 81–85, February, 1989. 相似文献
992.
The magnetic readback signal is generally assumed to be made up of linearly superposed single transition responses. As the transition spacing is reduced, this property is seen not to hold, With particulate disks, we find the head signal can be reconstructed as a linear superposition of variably spaced individual transitions, while with cobalt alloy film disks, both the spacing and the amplitude of individual transitions vary as a function of the data. This behavior is interpreted by a self consistent 2D recording model, linear superposition improves dramatically with lowM_{r}t disk media. 相似文献
993.
Identification of critical erosion prone areas in the small agricultural watershed using USLE,GIS and remote sensing 总被引:10,自引:1,他引:9
In the present study, Karso watershed of Hazaribagh, Jharkhand State, India was divided into 200 × 200 grid cells and average
annual sediment yields were estimated for each grid cell of the watershed to identify the critical erosion prone areas of
watershed for prioritization purpose. Average annual sediment yield data on grid basis was estimated using Universal Soil
Loss Equation (USLE). In general, a major limitation in the use of hydrological models has been their inability to handle
the large amounts of input data that describe the heterogeneity of the natural system. Remote sensing (RS) technology provides
the vital spatial and temporal information on some of these parameters. A recent and emerging technology represented by Geographic
Information System (GIS) was used as the tool to generate, manipulate and spatially organize disparate data for sediment yield
modeling. Thus, the Arc Info 7.2 GIS software and RS (ERDAS IMAGINE 8.4 image processing software) provided spatial input
data to the erosion model, while the USLE was used to predict the spatial distribution of the sediment yield on grid basis.
The deviation of estimated sediment yield from the observed values in the range of 1.37 to 13.85 percent indicates accurate
estimation of sediment yield from the watershed. 相似文献
994.
Stability of the zero equilibrium state of a full electromagnetic suspension of a rotor under decentralized control of each bearing is proved. The obtained results may be used for selecting the structure of the system for control of electromagnetic bearings. 相似文献
995.
In the present study, oil palm wood flour (OPWF) particles with less than 250 μm sizes have been used as filler materials
in the woven-glass-fiber reinforced epoxy composite. The hybrid composites were fabricated using a hand lay-up method and
cured at room temperature under a compressive load of 196 N (20 kg). The OPWF of 2.5 to 10 parts per hundred (pph) by weight
was used to evaluate its effect on impact strength of the hybrid composites at a range of temperature from −50 to 50 °C. The
impact strength, evaluated using V-notch Charpy method, showed reduction with increasing filler content up to 5 pph and then
the strength increment in those composites containing more than 5 pph OPWF. More severe damages were found in specimens with
higher filler contents resulting higher energy absorption during impact. The composites with a large amount of OPWF particles
deflected crack propagation paths or created obstacles at the crack tips and increased toughness of the composites. The impact
strength was found to decrease when the samples fractured at subzero temperatures and this happened because of the reduction
of the matrix ductility at lower temperatures. 相似文献
996.
G. A. Shanshurov 《Russian Electrical Engineering》2007,78(9):467-473
A model of an induction motor with an asymmetric stator winding is developed; it may be represented as two phases connected in parallel or in series and displaced is space by some angle. 相似文献
997.
A.V. Okotrub L.G. Bulusheva I.S. Larionova V.L. Kuznetsov S.L. Molodtsov 《Diamond and Related Materials》2007,16(12):2090-2092
X-ray absorption spectroscopy has been used for comparative study of electronic structure of detonation nanodiamonds (ND) purified using different oxidative treatments. The treatment of detonation soot with a mixture of nitric and sulphuric acids followed by ion exchange and ultrafiltration of hydrosol obtained was found to result in developing of ND surface coverage consisting of oxidized carbon species, which electronic state is close to that of strongly oxidized graphite. The deeper purification of ND was demonstrated to allow cleaning of ND particles from most of the oxidized carbon contaminations. 相似文献
998.
A. P. Petrova 《Polymer Science Series C》2007,49(3):219-219
Listed are the grades of heat-resistant adhesives developed under the Andrianov’s scientific guidance at the All-Russia Institute of Aviation Materials on the basis of organosilicon polymers. 相似文献
999.
1000.
Howard Kenneth I.; Krause Merton S.; Orlinsky David E. 《Canadian Metallurgical Quarterly》1986,54(1):106
Presents an analysis of the attrition dilemma in psychotherapy research and reviews the methods used to compensate for data loss. It is argued that attrition is not ultimately a problem of bias but a problem of lack of information. A reformulation is offered that integrates single-case studies with traditional group comparison methodology in an attempt to find optimal causal relations of treatments to outcomes. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献