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排序方式: 共有3488条查询结果,搜索用时 343 毫秒
21.
22.
抗盐降滤失剂SDX的研究与应用 总被引:7,自引:2,他引:5
介绍了抗盐降滤失剂SDX的合成方法与现场应用简况,评价了SDX的抗温、抗盐、防塌及配伍性能。试验结果表明,SDX能耐150℃以上的高温,可抗盐至饱和,具有良好的降滤失和抑制性能,与其它处理剂的配伍性好,适用于各种水基泥浆。 相似文献
23.
S Fukuda 《Bulletin of Materials Science》1996,19(6):887-891
The conventional approach has put emphasis upon reducing labour, and increasing efficiency and uniformity. But this holds
good only in the mass production paradigm. As we are entering the age of small production with far wider varieties, these
principles of yesterday should be re-examined. Labour itself sometimes gives satisfaction if it involves the joy of creation,
and longer time does not necessarily mean just patience, it sometimes turns into expectation if greater joy will be provided
later. Too much fitness for the purpose sometimes means lack of robustness and adaptability to the quickly and widely changing
environment. Thus, we should reconsider the items we thought important in the mass production age to aptly cope with the diversification
of each customer’s requirements. 相似文献
24.
25.
面对当前的发展趋势,文章提出了对初轧厂实行改造的设想:(1)改造工艺、技术装备,提高效率,效益和产品质量,从改善加热、原料、轧制下手;(2)发挥初轧优势,增强竞争力,发展连铸产品所不能取代的大压缩比、多品种多规格、小型化产品;(3)配合初轧厂的改造将产品种类向成材化方向转移。由此设想三个方面的具体作法。 相似文献
26.
This paper is mainly concerned with the Identification of an embryonic product platform from a family of products whose composition, configuration and characteristics are represented by Attributed Graphs. The problem becomes that of identifying the largest isomorphic sub-graph with the highest similarity. An algorithm is proposed for solving this problem together with several novel concepts. 相似文献
27.
本文阐述阻尼式限流器参数设计选择和产品系列规划的依据原则,并结合实例说明实施步骤与方法,以有助于限流器的正确设计与选用。 相似文献
28.
Boeing has been working on the development and implementation of STEP AP 210 since its inception. Using a combination of internally funded activities, external government contracts and multi-company pilots, Boeing has developed prototype tools to utilize AP 210 and is poised to move these tools into production. This paper begins with a brief overview of STEP and AP 210. The status of available AP 210 vendor translators (data generators), along with viewers and analysis programs (data consumers) is covered. Discussion continues with present and planned usage of AP 210 in several companies with the primary emphasis on implementation at The Boeing Company. The document concludes with a summary of key points. 相似文献
29.
The aim of this study was to evaluate the effects of paste properties on residence time during drying in a spouted bed dryer with inert bodies. The effect of paste solids content, surface tension, and viscosity on the residence time distribution and the mean residence times were studied using factorial experimental designs. The inert bodies used were glass and polyethylene beads. The mean residence times varied from 13.6 to 16.3 and 12.2 to 17.7 min for drying on glass and polyethylene beads, respectively. The analysis of variance showed that mean residence times significantly depended on solids content and surface tension for glass beads and also on viscosity for polyethylene beads. The residence time distributions for all conditions studied fitted well to the perfect mixing cell when applying the continuous stirred vessels in series model analysis. The powder density, flowability, and particle size depended on paste properties and inert type. 相似文献
30.
Luke O'Connor 《Journal of Cryptology》1994,7(3):133-151
We analyze a very general class of algorithms for constructingm-bit invertible S-boxes called bit-by-bit methods. The method builds an S-box one entry at a time, and has been proposed by
Adams and Tavares [2] and Forre [11] to construct S-boxes that satisfy certain cryptographic properties such as nonlinearity
and the strict avalanche criterion. We prove, both theoretically and empirically, that the bit-by-bit method is infeasible
form>6.
The author is currently employed by the Distributed System Technology Center (DSTC), Brisbane, Australia. Correspondence should
be sent to ISRC, QUT Gardens Point, 2 George Street, GPO Box 2434, Brisbane, Queensland 4001, Australia. 相似文献