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51.
多测井曲线的综合处理合成 总被引:9,自引:0,他引:9
测井曲线是地质分层的基础,但在利用单一测井曲线解决复杂地质问题时也存在多解性和局限性。为克服多解性,人们采用多种测井曲线进行地质分层,提高了分层的精度。本文在此基础上提出把多条曲线分别赋予不同的加权因子,然后进行归一化处理,形成一条标准综合参数测井曲线。此综合参数曲线突出了所选的多条测井曲线的公共信息,减少或削弱了单一测井曲线中的偶然误差,提高了综合后测井资料的可信度。该方法可应用于地质分层、岩性分析、含油气预测等诸多领域。应用时要注意,并非所选择的测井曲线种类越多越好,而是要选择那些最能反映地层单元特征信息的测井曲线。 相似文献
52.
CAO Wei-feng WANG Wen-boBeijing University of Posts Telecommunications Beijing P.R. China 《中国邮电高校学报(英文版)》2005,12(4)
1IntroductionCurrently,smart antenna technology can greatly en-hance system performance and i mprove the system ca-pacity so that it has been considered as a keytechnologyinthe third generation wireless communicationsystems .The researches on channel model , beamforming algo-rithms and receive algorithms have been widely carriedout and a great many of proposition have beensubmittedtothe 3th Generation Project Partner (3GPP) . Fromthe viewpoint of link-level and system-level research,many asp… 相似文献
53.
基于MATLAB在化工优化设计中的应用 总被引:2,自引:0,他引:2
结合化工优化计算的实例,着重介绍如何应用MATLAB7.0提供的优化工具箱来对线性规划及非线性规划模型进行求解。 相似文献
54.
In this work, we study dynamic provisioning of multicast sessions in a wavelength-routed sparse splitting capable WDM network
with an arbitrary mesh topology where the network consists of nodes with full, partial, or no wavelength conversion capabilities
and a node can be a tap-and-continue (TaC) node or a splitting and delivery (SaD) node. The objectives are to minimize the
network resources in terms of wavelength-links used by each session and to reduce the multicast session blocking probability.
The problem is to route the multicast session from each source to the members of every multicast session, and to assign an
appropriate wavelength to each link used by the session. We propose an efficient online algorithm for dynamic multicast session
provisioning. To evaluate the proposed algorithm, we apply the integer linear programming (ILP) optimization tool on a per
multicast session basis to solve off-line the optimal routing and wavelength assignment given a multicast session and the
current network topology as well as its residual network resource information. We formulate the per session multicast routing
and wavelength assignment problem as an ILP. With this ILP formulation, the multicast session blocking probability or success
probability can then be estimated based on solving a series of ILPs off-line. We have evaluated the effectiveness of the proposed
online algorithm via simulation in terms of session blocking probability and network resources used by a session. Simulation
results indicate that our proposed computationally efficient online algorithm performs well even when a fraction of the nodes
are SaD nodes. 相似文献
55.
基于神经网络基础上的两种系统安全综合评价方法 总被引:1,自引:0,他引:1
从工业企业生产发展的特点出发,在界定安全评价概念的基础上,从系统论的角度简要介绍了运用三层BP神经网络技术进行安全综合评价的方法和安全模糊综合评价方法。通过对这两种较为流行的安全评价方法进行分析,指出了传统评价方法的不合理性,辨证说明了这两种评价方法的优越性。 相似文献
56.
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58.
Pedro Ribeiro 《International journal for numerical methods in engineering》2004,61(15):2696-2715
A p‐version, hierarchical finite element for curved, moderately thick, elastic and isotropic beams is introduced. The convergence properties of the element are analysed and some results are compared with results published elsewhere or calculated using a commercial finite element package. It is verified that, with the proposed element, shear locking does not affect the computation of the natural frequencies and that low dimensional, accurate models are obtainable. Geometrically non‐linear vibrations due to finite deformations, which occur for harmonic excitations with frequencies close to the first three natural frequencies of vibration, are investigated using Newmark's method. The influence of the thickness, longitudinal inertia and curvature radius on the dynamic behaviour of curved beams are studied. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
59.
60.
Chouping Luo Marek Klisinski 《International journal for numerical methods in engineering》2004,61(2):159-188
The present study is a continuation of our previous work with the aim to reduce problems caused by standard higher order elements in contact problems. The difficulties can be attributed to the inherent property of the Galerkin method which gives uneven distributions of nodal forces resulting in oscillating contact pressures. The proposed remedy is use of piece‐wise linear weight functions. The methods to establish stiffness and/or mass matrix for 8‐node quadrilateral element in 2D are presented, i.e. the condensing and direct procedures. The energy and nodal displacement error norms are also checked to establish the convergence ratio. Interpretation of calculated contact pressures is discussed. Two new 2D 8‐node quadrilateral elements, QUAD8C and QUAD8D, are derived and tested in many examples, which show their good performance in contact problems. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献