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101.
针对我国动车组维修的特点,为动车组维修人员能够及时、快速地对动车组发生的故障进行分析和处理,运用人工智能的思想,结合数据库技术,设计了一套知识表示和知识库管理系统,对动车组故障信息及其原因信息、处理措施信息进行维护,处理了知识的正确性、完备性、冗余性、一致性检验,并在一定程度上实现了知识处理的自动化,对我国高速铁路动车组维修工作起到辅助支持作用.有很强的实际意义。 相似文献
102.
Enterprise applications may be classified into management applications used by managerial staffs for making decisions on business
operations, and engineering applications used by engineers for solving multidisciplinary design problems. In the literature,
enterprise application integration is extensively addressed in the context of management applications, but insufficiently
discussed in the engineering disciplines. Practitioners in manufacturing industries have for a long time feel the increasing
need of integrating engineering applications, in order to accelerate product development paces and improve design qualities.
Integrating engineering applications used in the multiple engineering disciplines has to cope with a number of challenges.
This paper focuses on one of the critical issues: parameter mapping and data transformation, which is of pivotal importance
to integrating engineering applications. Design parameter mapping provides a consistent approach to data extraction, storage,
display and manipulation among different data sources. Data transformation describes the operational logic of parsing input/output
files, extracting and transforming data, and maintaining consistency among multiple data sources.
相似文献
Chengen WangEmail: |
103.
To determine the maximum separation between events for nonrepetitive systems with max and linear constraints, there are the
“iterative tightening from above” (ITA) approach and the “iterative tightening from below” (ITB) approach. Since such systems
can be formulated as systems constrained by min–max inequalities, this paper gives an algorithm named MMIMaxSep for solving min–max inequalities. The algorithm is a generalization and a mathematically elegant reformulation of Yen et
al.’s MaxSeparation algorithm which uses the ITB approach. Our numerical experiments indicate that MMIMaxSep is very efficient. Moreover, MMIMaxSep has a unique advantage of being able to directly handle tree-represented min–max functions, and its complexity is closely
related to the complexity of computing cycle time of min–max functions.
相似文献
Yiping ChengEmail: |
104.
纵横嵌入术已为超大规模集成电路(VLSI)的平面设计提供了较完备的理论体系,在EREW PRAM(ExclusiveRread and ExclusiveWrite Parallel Random Access Machine)并行计算模型上,使用O((m+n)/ logn)个处理器,时间复杂度为O(logn),对四正则图的纵横嵌入图优化,使图中边的总折数达到最少且所占面积最小。 相似文献
105.
On lower bounds of the closeness between complexity classes 总被引:1,自引:0,他引:1
Bin Fu 《Theory of Computing Systems》1993,26(2):187-202
We show that if an NP-m-hard set is the union of a set in Pbtt(Sparse) and the setA, then NP Pdtt(A). Since co-NP, R, and FewP are closed under
dtt
P
-reductions, so no NP-m-hard set is the union of a set in Pbtt(Sparse) and a set in co-NP (resp. R, FewP) unless NP = co-NP (resp. NP = R, NP = FewP). We also study the distance between many important complexity classes. LetA,B be two sets. The distance function dist
A,B
is defined as in [S1] such that dist
A,B
(n) is the number of strings of length n inA B = (A – B) (B – A). We show that there exists a setA in p(k + 1)–tt(Sparse) such that, for everyB in P
k–tt(Sparse), dist
A,B
has an exponential lower bound.This research was supported in part by HTP 863. 相似文献
106.
In this paper, the air film formation behavior of air cushion belt conveyor with stable load is studied. The air cushion field is analyzed by means of theoretical derivation, numerical simulation and experimental research. An intelligent experiment platform is developed. Three dimensional pressure distribution of air film and the air film thickness distribution along the conveyor belt in the width direction are obtained. The experimental result is analyzed by comparing with theoretical calculation and numerical simulation. The numerical and theoretical results are in good agreement with those obtained from experiments. The air film formation behavior pattern of air cushion belt conveyor with stable load is presented. The optimized film thickness and pore distribution are obtained based on the comprehensive energy consumption. This study provides a basis for the optimization design of air cushion belt conveyor. 相似文献
107.
108.
一体化标识网络安全性能测试 总被引:1,自引:0,他引:1
分析一体化标识网络对网络攻击的抵抗能力以及在网络安全方面的优势,并以ICMP Flood攻击为例,使用思博伦Test-Center测试仪对一体化网络和传统网络分别进行安全攻击测试,从而评估一体化网络的安全性能.测试结果显示,对于DDoS攻击,相比于传统网络较明显受到攻击的影响,一体化网络能有效抵御攻击,保护了核心网的安全性. 相似文献
109.
110.
分析信息系统工程监理工作特点和信息技术服务各种技术参考模型,研究信息系统工程监理技术参考模型的组成和基本要素,提出适合监理国家标准的技术参考模型。 相似文献