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61.
谢庆红 《重庆理工大学学报(自然科学版)》2003,17(1):65-67
我国已加入WTO,并将遵守其游戏规则逐渐开放国内市场,内资零售企业将获得更多商机,也将面临巨大的压力和激烈的竞争,文中结合我国零售业现状,研究国外大型零售企业的成功经验,探讨我国零售企业的应对策略。 相似文献
62.
地震采集中检波器自然频率的试验分析 总被引:9,自引:1,他引:8
王增明 《石油地球物理勘探》2003,38(3):308-316
为了达到提高分辨率的目的,对不同自然频率的检波器进行了多次试验。通过试验分析认为,检波器在自然频率方面有所差别,在单炮记录上表现为对低、高频干扰压制情况有所不同,但是资料通过处理后,几种检波器的频谱和能量均无明显的差别。高分辨率勘探不等于高频勘探,而是一种宽频带的勘探,所以选择自然频率低的检波器有利于高分辨率勘探。 相似文献
63.
Heat convection in ballast mass in railway embankments is a problem of heat convection in porous media. In order to calculate the temperature distribution of the Qing-Tibet railway embankment from the governing equations used to study forced convection for incompressible fluids porous media, detailed finite-element formulas for heat convection in porous media are derived using Galerkin’s method. The temperature distributions on central lines of the traditional railway embankment, the ripped-rock embankment, and the ripped-rock revetment embankment that were constructed on July 15, 2002 have been analyzed and compared on July 15, October 15 in the 24th year after construction, and January 15 in the 25th year after construction under the climatic and geological conditions on the Qing-Tibet Railway. The calculated results indicate that the traditional railway embankment will raise the permafrost temperature under the embankment base and make the permafrost embankment thermally unstable. The ripped-rock embankment and the ripped-rock revetment embankment will reduce the permafrost temperature under the embankment base in cold regions, therefore maintaining the thermal stability of permafrost. However, the ripped-rock embankment needs more rock mass while the ripped-rock revetment embankment need less rock mass, and its construction cost is lower than that of the former. Therefore, it is highly recommended that the ripped-rock revetment embankment be used for the Qing-Tibet railway embankment structure in high temperature permafrost regions so that the permafrost embankment can be protected as much as possible. 相似文献
64.
This presidential column announces the significant internal changes of Division 13 of the Consulting Psychology Journal. The journal is now published by the Educational Publishing Foundation, which is associated with the American Psychological Association in order to increase the quality, quantity, and diversity of submissions to the journal. The author outlines the steps that will be taken to make the Division a more viable and inviting organization for members in ways that are obvious and easily accessible to them. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
65.
东海西湖凹陷探井钻井完井液技术 总被引:2,自引:2,他引:0
介绍了东海西湖凹陷的储层特征。在分析探井储层损害原因的基础上,提出了优化的海水钻井完井液体系。两口井应用表明,储层保护效果明显。 相似文献
66.
Designing Templates for Mining Association Rules 总被引:3,自引:0,他引:3
Current approaches to data mining usually address specific userrequests, while no general design criteria for the extraction of associationrules are available for the end-user. In this paper, we propose aclassification of association rule types, which provides a general frameworkfor the design of association rule mining applications. Based on theidentified association rule types, we introduce predefined templates as ameans to capture the user specification of mining applications. Furthermore,we propose a general language to design templates for the extraction ofarbitrary association rule types. 相似文献
67.
张蓓 《浙江工业大学学报》2007,(2)
本文对我国在明末和清代西学东渐过程中的图书翻译进行了梳理和剖析,总结了这一时期西学翻译的历史概况,阐述了东西文化交流中翻译图书的重要作用,以及历史上有识之士对于西学翻译的贡献。 相似文献
68.
Summary The Polymer Section of the Santa Barbara Workshop on Modeling of Materials is briefly reviewed. Motivation and need for modeling in polymer-based materials are outlined and the recommendations resulting from the workshop reported. 相似文献
69.
Cost estimation of structural skeleton using an interactive automation algorithm: A conceptual approach 总被引:1,自引:0,他引:1
This paper addresses a new concept for generating bills of quantities (B.o.Qs) using AutoCAD drawings for a building project, which demonstrates the application of Industry Foundation Class (IFC), developed by International Alliance for Interoperability (IAI). The procedure considers types of materials and the structural shapes of the AutoCAD drawings to compute the cost of the structural skeleton elements using interactive automation. The main concept focuses on using layer computation of the AutoCAD drawing after converting it into a drawing inter-exchangeable file format (DXF). Once the coordinates are detected, it is easier to determine the area and volume for any structural shape, including circles and polygons. The extracting method is a new technique for structural engineers and quantity surveyors to estimate required material for beam, columns, slabs and foundations. The algorithm extracts and recognizes the layers and objects from a two dimensional DXF drawing along with the coordinates information. The results obtained using this technique are more accurate and reliable than manual procedures or any other traditional techniques. In this paper, an automated and interactive procedure for B.o.Q computation is demonstrated. The process involves a user-friendly interface, dynamic linking to the structural drawings and tracking of B.o.Q modifications at the same time. 相似文献
70.
In this paper, we propose an efficient method for mining all frequent inter-transaction patterns. The method consists of two phases. First, we devise two data structures: a dat-list, which stores the item information used to find frequent inter-transaction patterns; and an ITP-tree, which stores the discovered frequent inter-transaction patterns. In the second phase, we apply an algorithm, called ITP-Miner (Inter-Transaction Patterns Miner), to mine all frequent inter-transaction patterns. By using the ITP-tree, the algorithm requires only one database scan and can localize joining, pruning, and support counting to a small number of dat-lists. The experiment results show that the ITP-Miner algorithm outperforms the FITI (First Intra Then Inter) algorithm by one order of magnitude. 相似文献