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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
141.
本文主要讨论了异常数据挖掘在实际中的应用,简要地介绍了异常点的定义、分类及异常数据挖掘的定义、功能等,详细的介绍了异常数据挖掘技术在金融领域、电信领域、商业领域中和生物医学以及DNA分析中的应用。 相似文献
142.
吴亚林 《计算机光盘软件与应用》2010,(8):185-185
在计算机日益普及的今天,高职院校《计算机应用基础》课程应如何定位?如何实施教学以达到教学目标?我们应以学生为中心,根据高职生计算机知识结构与应用能力的要求来确定适当的教学内容,选择恰当的教学方法、合适的教学步骤,安排充足的练习时间,加强实践技能培养,改革考核方法。 相似文献
143.
G.K. Korotaev F.-X. Le Dimet S.V. Stanichny L. Wu 《Remote sensing of environment》2008,112(4):1464-1475
In this article we propose a new method to estimate ocean mesoscale structures of the surface current velocity by processing sea surface satellite images. Assuming that the intensity level can be described by a transport-diffusion equation, the proposed approach is based on variational assimilation of image observations within a simple transport-diffusion model. This approach permits to retrieve the current velocity field from a sequence of satellite images. Results of processing synthetic data and real NOAA-AVHRR satellite images are presented and commented. 相似文献
144.
We present a mechanism for reservations of bursty resources that is both truthful and robust. It consists of option contracts
whose pricing structure induces users to reveal the true likelihoods that they will purchase a given resource. Users are also
allowed to adjust their options as their likelihood changes. This scheme helps users save cost and the providers to plan ahead
so as to reduce the risk of under-utilization and overbooking. The mechanism extracts revenue similar to that of a monopoly
provider practicing temporal pricing discrimination with a user population whose preference distribution is known in advance. 相似文献
145.
An atomistic-continuum inhomogeneous material model for the elastic bending of metal nanocantilevers
The equivalent elastic modulus of nanocantilever can be obtained using atomistic simulation. However, the use of this modulus to predict the bending of nanocantilever results in significant error compared with direct atomistic simulation. The error originates from the surface effect. In our current work, the nanocantilever is considered as an inhomogeneous continuum material. The distributions of materials parameters at the cross-section, such as atomistic elastic constants, are calculated from atomistic simulations. These atomistic-information-based materials parameters are used as inputs to continuum model. A numerical example case validates the presented model and methodology. To correctly predict the structure-property relations of elemental nano-structures are very important for the design of nano-devices. Our continuum model includes nano-effects and provides another way to study nanomechanics. 相似文献
146.
The suitability of computational simulation of the Belousov–Zhabotinskii oscillating chemical reaction by differential kinetic methodology for resolving nonlinear multi-component system is demonstrated in this work. According to the Field–KÖrÖs–Noyes mechanism and the Oregonator model, the change of the concentrations of HBrO2, bromide ion and cerium ion are simulated. The results of computational simulation are consistent with experimental results very well. At the same time, the effect of variables and parameters, especially the rate constant on the oscillation curve, are investigated deeply. A simple method of estimating rate constants is obtained through simulation the concentrations of key components of the system, and then comparison the simulation results with the experimental ones. The reasonable rate constant is also proposed. 相似文献
147.
148.
Zhixue Wu 《Structural and Multidisciplinary Optimization》2009,37(6):625-634
The goal of this work is to obtain optimal hole shape for minimum stress concentration in two-dimensional finite plates using
parameterized geometry models. The boundary shape for a hole is described by two families of smooth curves: one is a “generalized
circular” function with powers as two parameters; the other one is a “generalized elliptic” function
a and b are ellipse axes) with powers as two parameters and one of the ellipse axes as the third parameter. Special attention is
devoted to the practicability of parameterized equations and the corresponding optimal results under the condition with and
without the curvature radius constraint. A number of cases were examined to test the effectiveness of the parameterized equations.
The numerical examples show that extremely good results can be obtained under the conditions with and without curvature radius
constraint, as compared to the known solutions in the literature. The geometries of the optimized holes are presented in a
form of compact parametric functions, which are suitable for use and test by designers. It is anticipated that the implementation
of the suggested parameterized equations would lead to considerable improvements in optimizing hole shape with high quality. 相似文献
150.
介绍一种使用WinHex软件恢复找回u盘文件的方法,利用这种方法,u盘使用者通过一些简单的操作步骤,可尝试对偶尔出现的文件误删、误格式化操作进行恢复,挽回损失。 相似文献