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21.
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
22.
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
23.
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
24.
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
25.
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
26.
人的因素在家具质量管理工作中有着举足轻重的作用,各个层次的工作者有着不同的质量职责,发挥不同的作用。本文立足人的因素来解析企业质量管理体系中各层工作者的质量工作,及对质量管理体系运行的作用。 相似文献
27.
与国外大石油公司相比,当前中石油在成品油终端销售方面还存在一些差距,比如管理较落后,流通费用较高,员工素质偏低,技术手段还不够先进,品牌影响力还不够强等等。要提高中石油在成品油市场上的地位,还需要从企业竞争能力、价值链优化整合、市场定位、营销策略等方面进行不断的探索与努力。 相似文献
28.
Colin Fyfe 《Data mining and knowledge discovery》2007,14(2):207-224
We review a new form of self-organizing map which is based on a nonlinear projection of latent points into data space, identical
to that performed in the Generative Topographic Mapping (GTM) [Bishop et al. (1997) Neurl Comput 10(1): 215–234]. But whereas
the GTM is an extension of a mixture of experts, our new model is an extension of a product of experts [Hinton (2000) Technical
report GCNU TR 2000-004, Gatsby Computational Neuroscience Unit, University College, London]. We show visualisation results
on some real data sets and compare with the GTM. We then introduce a second mapping based on harmonic averages and show that
it too creates a topographic mapping of the data. We compare these mappings on real and artificial data sets.
Responsible editor: Soumen Chakrabarti. 相似文献
29.
SHARED: An information model for cooperative product development 总被引:6,自引:0,他引:6
One fundamental issue in developing collaborative engineering systems is the representation of product information which supports communication and coordination. This product information includes not only the geometric and physical properties of the product and its parts, but also information about functions, constraints and the design rationale. In this paper, we describe an information model, SHARED, which was developed for encoding product information in DICE, a distributed and integrated environment for computer-aided engineering. SHARED provides multiple levels of both functional and geometric abstractions, multiple views and techniques for maintaining consistency between the various abstractions and views. These elements are essential for a good representation model of product information. The use of the SHARED model is illustrated through an example, depicting the various representations of a product as it evolves through the design process. The SHARED model has been implemented over a distributed OODBMS as a toolkit/framework for developing environments which need to model, manipulate and communicate product information between distributed cooperating applications, while supporting coordination between them. 相似文献
30.
TTI hydraulics and erosion control laboratory research field performance of erosion-control blankets
Storm water management issues facing the Texas Department of Transportation in the late 1980s led to the development of a coordinated research program with the Texas Transportation Institute. Researchers developed methodologies for evaluating the field performance of various erosion control technologies of the most widely used products within the Department's construction and maintenance operations. From these methodologies, the Hydraulics and Erosion Control Laboratory was designed and constructed. Currently, participants include private industry (manufacturers of erosion control products), transportation researchers (TTI), and the public sector (TxDOT).The results reported in this paper reflect 2 years of erosion-control blanket research. The study objectives were to determine the effectiveness of erosion-control blankets on the growth of warm-season perennial grasses and their ability to prevent sediment loss in a sloped condition.The laboratory simulates the highway environment with the sloped plots (6 m in width) located on an earthen embankment that is 300 m in length and 6.75 m in height (94 ft. by 22 ft., vertically). A randomized experimental design was replicated on two soil types (sand and clay) for each slope condition (3:1 or 2:1) with a control.In general, the results indicate better combined results relating to sediment retention and vegetation establishment performance for erosion-control blankets on sandy soils (noncohesive) regardless of slope condition (3:1 or 2:1) or material type. A minimum of 50% more sediment was retained on the sandy treatment plots and a 45% more vegetation coverage was achieved compared with the control plots. When analyzed by material type related to performance, excelsior, synthetic blends, and straw/coconut blends performed the best. For clay soils (cohesive), regardless of slope condition (3:1 or 2:1), the combined results indicate a minimum of 75% more sediment was retained and a minimum of 5% more vegetation establishment was achieved compared with the control plots. When analyzed by material type related to performance, excelsior, straw, and straw/coconut blends performed the best. 相似文献