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41.
K K Leong K M Yu W B Lee 《厦门大学学报(自然科学版)》2002,(Z1)
Product data management (PDM) has been accepted as an important tool for the manufacturing industries. In recent years, more and mor e researches have been conducted in the development of PDM. Their research area s include system design, integration of object-oriented technology, data distri bution, collaborative and distributed manufacturing working environment, secur ity, and web-based integration. However, there are limitations on their rese arches. In particular, they cannot cater for PDM in dis... 相似文献
42.
研究了显微组织对NdFeB磁体iHc及β(iHc)的影响,对NdxFe93-xB7磁体,x从16增加到28时,Hc增加了55%,β(iHc)降低了约11%;进一步优化显微组织,增加富Nd晶间相,减弱晶粒间的磁耦合作用及消除晶粒表面的高退磁场区域,不仅可提高磁体的矫顽力,亦可显著改善其矫顽力温度系数。 相似文献
43.
Chromosomal effects of adeno-associated virus vector integration. 总被引:17,自引:0,他引:17
Adeno-associated virus (AAV) vectors are currently being used in several clinical gene-therapy trials (see the NIH OBA Human Gene Transfer Clinical Trials Database); however, little is known about the chromosomal effects of vector integration. Here we report that integrated vector proviruses are associated with chromosomal deletions and other rearrangements and are frequently located on chromosome 19 (although not at the wildtype AAV integration site). 相似文献
44.
本文详细论述了利用废铝生产氯化铝过程中,设备及各控制因此对产品质量和颗粒度的影响,(?)了适宜的控制条件和设计要求,为生产不同用户需求的合格产品提供了可靠的依据。 相似文献
45.
46.
Jacob W. Ulvila 《Journal of forecasting》1985,4(4):377-385
Recent years have seen an increasing cross-fertilization between the fields of decision analysis and forecasting. Decision-analytic models often require forecasts as inputs, and aspects of the Bayesian decision-theoretic framework underlying decision analysis have proved useful to forecasting, particularly in contexts where subjective judgemental inputs are required. This paper describes the use of decision tree analysis for forecasting and illustrates its use for corporate divisional forecasting and planning. A specialized decision-analytic technique, acts as events, is also described and illustrated to forecast a new product's earnings. Conclusions are drawn about the applicability of decision analysis for forecasting. 相似文献
47.
J. W. Faigle H. Stierlin H. Mory T. Winkler H. -P. Kriemler 《Cellular and molecular life sciences : CMLS》1985,41(4):476-478
Summary Indoxyl derivatives were detected as minor products among the urinary metabolites of two trial drugs, a benzodiazepine (GP 55 129) and a benzophenone (CGP 11 952). Their structures were elucidated by NMR and mass spectroscopy. Presumably, metabolites containing potential aldehyde functions react spontaneously with endogenous indoxyl. Such derivatives have not hitherto been encountered in drug metabolism. 相似文献
48.
49.
结合边连通度,本文探讨了3-边连通简单网的独立数与上可嵌人性的关系,我们得到了下列结果:设G是一个3-边连通简单图,α(G)是G的独立数,若α/(G)≤5,则G是上可嵌入的,同时我们又得到了两个在3-边连通意义下最小的非上可嵌入图例. 相似文献
50.
Gao Liang 《上海交通大学学报》2004,38(Z2)
This paper is mainly aimed at the mechanics characteristic elas of ticity-plasticitystickiness existed in the CWR (continuously welded rails) track plane of the railway crushed stone ballast. As an important mechanics parameter of the CWR track plane, the ballast resistance is mainly influenced by this mechanics characteristic. Through the systematic experimental research and the theoretical analysis, this mechanics characteristic of the ballast resistance is revealed and a reasonable theoretical model is built for it. This study set a sound foundation for further studying the CWR track deformation property. It will be beneficial to the development of high-speed railway in China. 相似文献