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991.
B. V. Kuteev V. Yu. Sergeev V. A. Belopol’sky V. M. Timokhin R. Burhenn 《Technical Physics Letters》2003,29(4):302-304
Experiments performed on a Wendelstein 7-AS stellarator revealed asymmetry of the cloud of an ablating carbon pellet. The cloud is elongated in the direction of large radius toward stronger fields, that is, opposite to the direction expected due to the toroidal drift. In order to study the effect in more detail, the three-dimensional structure of the cloud was analyzed by computer tomography. The results confirmed asymmetry of the cloud. This asymmetry is related to a drift flow existing in the plasma and directed along large radius toward stronger fields. The drift velocity is numerically estimated at ~300 m/s. 相似文献
992.
Susskind Alex M.; Kacmar K. Michele; Borchgrevink Carl P. 《Canadian Metallurgical Quarterly》2003,88(1):179
The authors proposed and tested a model describing the relationship between customer service providers' perceptions and attitudes toward their service-related duties and their customers' perceptions of satisfaction with their service experiences. Results indicated that the perception of having standards for service delivery in an organization is strongly related to line-level employees' perceptions of support from coworkers and supervisors. Perceived support from coworker, was significantly related to service providers' customer orientation, whereas perceived support from supervisors showed a weaker relationship to a customer orientation. Ultimately, service providers' customer orientation was strongly related to customers' satisfaction with service. Finally, a set of post hoc analyses indicated that coworker and supervisory support explained a greater proportion of incremental variance in the model than did perceived organizational support alone. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
994.
Determination of shear strength values according to EN 408 总被引:1,自引:0,他引:1
This paper presents the results of 382 shear tests carried out according to EN 408. The test pieces consisted of spruce (Picea
abies) and varied in density and ring width orientation (radial, tangential and at an angle of 45° to the steel plates). In
addition pieces containing pith and knots were tested. The paper discusses problems observed when using this test configuration
and shows that the test results do not support the characteristic shear strength values as given in EN 338. Moreover, the
test results do not support the relationship between characteristic shear strength and characteristic bending strength as
given in EN 384.
Résumé Cet article présente les résultats de 382 essais de cisaillement menés conformément à EN 408. Les éprouvettes d’essai sont en épicéa (Picea abies) et présentent une variabilité en termes de masse volumique et d’orientation des cernes d’accroissement (radiale, tangentielle, à un angle de 45° par rapport aux plaques métalliques). Des éprouvettes supplémentaires contenant du cœur et des nœuds ont également été testées. L’article évoque les problèmes qui ont été mis en évidence lors de l’utilisation de ce dispositif expérimental et montre que les résultats expérimentaux ne sont pas en accord avec les valeurs caractéristiques de résistance au cisaillement données dans EN 338. De plus, ces résultats ne confirment pas la relation entre résistance caractéristique au cisaillement et résistance caractéristique à la flexion telle que stipulée dans EN 384.相似文献
995.
O. E. Narivs’kyi 《Materials Science》2007,43(1):124-132
We have studied the micromechanism of corrosion fracture of heat-transfer plates of a heat exchanger. The operation of heat
exchangers under conditions of contamination of the plates with a sediment from water leads to their local corrosion under
the sediment. The conditions of operation of the heat exchangers being equal, heat-transfer plates made of AiSi316Ti steel
worked 2.36 times as long as those of AiSi304L steel. The corrosion fracture of plates under the sediment began from pitting
initiation near nonmetallic inclusions of a certain nature. Afterwards, these pittings built up into corrosion spots by the
mechanism of stress corrosion and hydrogen embrittlement.
__________
Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 43, No. 1, pp. 110–116, January–February, 2007. 相似文献
996.
Published data on the preparation procedures, stability, and complexation of U(III) in aqueous solutions are summarized and correlated. Reactions with inorganic and organic free radicals studied by the flash radiolysis method, the spectroscopic properties, the extraction and ion-exchange behavior of U(III), and methods for isolation of solid U(III) compounds from aqueous solutions are discussed. 相似文献
997.
Boundary objects are a critical, but understudied, theoretical construct in CSCW. Through a field study of aircraft technical
support, we examined the role of boundary objects in the practical achievement of safety by service engineers. Their resolution
of repair requests was preserved in the organization’s memory via three compound boundary objects. These crystallizations
did not manifest a static interpretation, but instead were continually reinterpreted in light of meta-negotiations. This suggests
design implications for organizational memory systems which can more fluidly represent the meta-negotiations surrounding boundary
objects. 相似文献
998.
999.
1000.
Arun K. Nanda Honda Shing Ten-Hwan Tzen Lionel M. Ni 《Journal of Parallel and Distributed Computing》1991,12(4)
A standard metric conventionally employed to compare the performance of different multiprocessor systems is speedup. Although providing a measure of the improvement in execution speed achievable on a system, this metric does not yield any insight into the factors responsible for limiting the potential improvement in speed. This paper studies the performance degradation in shared-memory multiprocessors as a result of contention for shared-memory resources. A replicate workload framework with a flexible mechanism for workload specification is proposed for measuring performance. Two normalized performance metrics—efficiency and overhead factor—are introduced to quantify the factors limiting performance and facilitate comparison across architectures. Finally, the proposed model is employed to measure and compare the performance of three contemporary shared-memory systems, with special emphasis on the newly released BBN Butterfly-II (TC2000), currently undergoing Beta test. 相似文献