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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
911.
W Matthiessen N Sch?nfeld H Mauch U Wahn A Grassot 《Canadian Metallurgical Quarterly》1993,118(5):139-144
The chest radiograph of a 35-year-old man with fatigue, exertional dyspnoea and haemoptyses revealed a cavity in the left upper lobe and a shrunken left lung with radiolucency greater than that on the right. Acid-fast rods in sputum were identified as Mycobacterium kansasii on culture. Scintigraphy showed a 9% residual perfusion on the left and abnormal ventilation, compatible with Swyer-James syndrome. This had favoured the development of a mycobacterial infection. There was also a decrease in ciliary function (rate of 4-7 Hz, normal: 10-11). Treatment, begun when tuberculosis had been suspected, was after sensitivity tests changed to a combination of rifampicin (600 mg), ethambutol (1600 mg) and protionamide (500 mg) daily. There was marked regression of the findings within 4 weeks, but treatment was prematurely stopped after 11 months. Two years later there was a recurrence which again responded well to the same drug regimen with additional sulphamethoxazole (1600 mg/d). 相似文献
912.
S. N. Syromyatnikov 《Journal of Engineering Physics and Thermophysics》1993,65(2):745-751
Nonlinear spherical vapor bubble oscillations in the main resonance region in a viscous incompressible fluid under the action of a periodically varying external pressure are considered using the multiscale method. Saddle-node type bifurcations that appear when the amplitude or frequency of the external effect changes are investigated.Institute of Thermal Physics of the Ural Branch of the Russian Academy of Sciences, Ekaterinburg. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 65, No. 2, pp. 164–170, August, 1993. 相似文献
913.
Discusses the deconstructive shift in the conception of mothers and mothering from a unitary category of women in a biological relationship with their offspring to a more fluid constellation of active maternal relations. The author suggests a new parenting subject that transcends gender, constructed through the work of intersubjective dyads. Two questions are addressed: (1) How might the representation of such maternal relationships and their internalization be envisioned? (2) How might a changing conception of internalized maternal representations affect psychoanalytic practice? With reference to J. Bowlby's (1980) concept of internal working models of attachment, and to more recent infant research, the concept of maternal functions (specifically, functions of security, regulation, and recognition) is introduced as central to the mothering relation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
914.
915.
N. A. Samoilov 《Chemical and Petroleum Engineering》2002,38(7-8):437-443
916.
Formulation of the problem of designing the optimal structure of an active system was considered within the framework of the game-theoretical model of interaction of its participants. Solution and the results of studying the control mechanisms in applications such as in-house management and multiagent systems were presented. 相似文献
917.
Relation between abrasion resistance and flexural strength of high volume fly ash concrete 总被引:2,自引:0,他引:2
In this paper, abrasion of high volume fly ash (HVFA) concretes made with 50% and 70% of cement replacement with fly ash was
assessed in terms of its relation to flexural tensile strength. Comparisons were made between normal Portland cement (NPC)
concrete and fly ash concrete. Comparisons were also made between fly ash concretes. Investigation results have shown that
the abrasion resistance increased as flexural tensile strength increased. Analysis of the results showed that, for concrete
with tensile strength of greater than 4–5 MPa, the abrasion resistance of HVFA concrete with 70% replacement with cement was
found to be higher than that of counterpart control NPC concrete and concrete made with 50% fly ash. The comparison between
the relation of abrasion to compressive strength and abrasion to flexural tensile strength made in terms of R2 of the linear regression showed that a stronger relation existed between abrasion and flexural tensile strength than that
of abrasion to compressive strength of the concrete studied.
Résumé L'étude a pour but d'estimer la relation entre la résistance à l'usure avec la résistance à la traction en flexion des bétons contenant de 50% et 70% de cendres volantes. On a comparé le béton pur au béton contenant des cendres volantes. Des comparaisons ont été faites également entre les différents bétons contenant des cendres volantes. Les resultats de la recherche ont montré que la résistance à l'usure augmente à mesure que la résistance à la traction en flexion de 4∼5 MPa ont une résistance à l'usure plus grande s'ils contienneint 70% de cendres volantes que s'ils étaient purs ou contenaient 50% de cendres volantes. La comparaison entre les relation de la résistance à l'usure en compression et de la résistance à l'usure en traction a été établie en termes de R2 de la régression linéaire. On a prouvé qu'une relation plus forte a été obtenue entre la résistance à l'usure et la résistance à la traction en flexion par rapport à la résistance à l'usure en compression du béton étudié.相似文献
918.
Michael E. Gorman 《工程教育杂志》2002,91(3):327-332
In order to implement the Accreditation Board for Engineering and Technology (ABET) engineering criteria, it is important for engineering educators to understand different types of knowledge and how these types relate to the outcomes described in Criterion 3. This paper first provides a heuristic for framing a program's educational objectives by identifying exemplars of the types of engineers a program seeks to graduate. Three sections then follow, each addressing categories of knowledge: tacit knowledge, four types of knowledge that can either be tacit or explicit, and knowledge created and shared in teams. Examples of the relationship of traits of knowledge to the outcomes in Criterion 3 are provided. The paper concludes with a brief discussion of how these types of knowledge are imbued in engineering students at the University of Virginia, as well as suggestions for additional ways in which they could be infused into engineering curricula. 相似文献
919.
920.