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991.
Synthetic Aperture Radar (SAR) imaging has the inherent random speckle noise, which seriously affects the quality of the SAR image, and it is very important to study the suppression of the speckle noise. In view of the fact that the traditional spot noise suppression method could not remove speckle noise while protecting the image texture information, a novel filtering algorithm is proposed based on the soft morphological and parameterized symmetric logarithmic image processing model. The proposed algorithm combines the flexibility of the order-statistic soft morphological operations and the characteristic of the parameterized symmetric logarithmic image processing model which establishes a parameterized symmetric structure processing part of the image, which can suppress speckle noise while protecting the texture information on the image. In order to validate the despecking performance of the proposed algorithm, we compare the effect of the filter with some of the existing filtering algorithms, and use some of the image evaluation parameters of the suppress speckle noise image to evaluate the performance of the SMPSLIP filtering algorithm. Experimental results show the effectiveness of this algorithm. 相似文献
992.
Radio frequency interference suppression is a very important issue in applications of high-frequency surface wave radar. This paper proposes a new interference suppression algorithm which makes use of RF interference azimuth information on the basis of learning common RF interference suppression algorithms and spatial spectrum estimation. First, we apply the MUSIC algorithm to estimate the interference azimuth and obtains the interference's signal space after the first Fourier transform; next, we use space decomposition to decompose the radar echo and obtain interference components; last, we subtract radio frequency interference components from the original signals. This algorithm can do great amount of RF interference suppression in actual data and get good results. 相似文献
993.
It is a key challenge to exploit the label coupling relationship in multi-label classification (MLC) problems. Most previous work focused on label pairwise relations, in which generally only global statistical information is used to analyze the coupled label relationship. In this work, firstly Bayesian and hypothesis testing methods are applied to predict the label set size of testing samples within their k nearest neighbor samples, which combines global and local statistical information, and then apriori algorithm is used to mine the label coupling relationship among multiple labels rather than pairwise labels, which can exploit the label coupling relations more accurately and comprehensively. The experimental results on text, biology and audio datasets shown that, compared with the state-of-the-art algorithm, the proposed algorithm can obtain better performance on 5 common criteria. 相似文献
994.
An accurate chlorine bulk decay model is needed to ensure that potable water meets the microbial and the chemical safeties at the treatment plant and throughout the distribution. Among the mathematical models available,the general second-order chlorine bulk decay model( GBDM) is the most fundamentally sound.Application of the GBDM,however,has been hindered by its numerous fictive parameters and lack of an analytical solution. This theoretical work removes the two obstacles. The GBDM is solved through transformation and integration. The analytical solution provides deep insights into the GBDM and facilitates the parameterization and sensitivity analysis. The background natural organic matter( NOM) is characterized with the probabilistic distribution of functional groups. It reveals that the mean of the function group distribution is correlated with the initial chlorine decay rate coefficient( κ_0). A simple formula is developed to determine κ_0 directly from the initial chlorine decay. The theoretical treatment reduces the fictive parameters to a minimum. For the common lognormal distribution,the GBDM needs only three parameters,well defined as initial chlorine demand X_0,median rate coefficient km,and heterogeneity index σ. For more complicated scenarios,composite distributions are constructed through superposition of individual distributions. A highlighted example is to predict chlorine decay in blends of different waters. With the theoretical and mathematical advancement here,the GBDM can be applied effectively to any reactive background matter in any reaction systems. 相似文献
995.
保温措施是既有建筑节能改造中最有效的节能措施之一。在墙体节能改造设计中,保温材料种类及其厚度的确定是至关重要的,受到多个目标参数的制约和影响。基于反问题的研究方法,建立数值计算方法与多目标遗传算法NSGA-Ⅱ相结合的优化模型,以单位面积墙体全年总能耗和保温材料成本为目标参数,对成都地区某既有建筑墙体节能改造的保温材料种类与厚度进行了协同设计。结果表明,采用常规的保温厚度,常用的8种保温材料中有6种都不是最优解,但是可以通过改变保温材料的厚度或单价等方法使解向Pareto前沿逼近,以实现单位面积墙体年总能耗最小和改造成本最小之间的平衡。 相似文献
996.
大多数用户相似性算法在计算用户相似性时只考虑了用户间的共同评分项,而忽略了用户其他评分中可能隐藏的有价值信息.为了准确评估用户间的相似性,提出了一种基于KL散度的用户相似性协同过滤算法.该算法不仅利用了共同评分项,还考虑了其他非共同评分信息的影响.该算法充分利用了用户的所有评分信息,提高了用户相似性度量的可靠性和准确性.实验结果表明,该算法优于当前主流的用户相似性算法,且在没有共同评分信息的条件下,仍能有效地完成用户相似性度量,解决了对共同评分项的完全依赖问题,具有更好的适应性. 相似文献
997.
由于强噪声背景的影响,在进行光谱探测的过程中收集到的信号很微弱。为了能有效的去除噪声,提出了采用锁相放大算法去除噪声提取光谱特征信号的方法。研制编写锁相放大算法,对收集的光谱数据进行处理,分析处理后的结果,光谱特征获得了放大,进一步进行两种结果的中值归一化对比,该光谱曲线与原始光谱曲线线型基本一致,且具有平滑去噪效果。该成果对微弱光谱信号去除噪声的研究具有实际意义。 相似文献
998.
以解决机器学习的样本提取问题、提高车辆识别的精度为目的,以Adaboost算法、级联检测方法、样本自反馈方法为基础,提出了一种面向车辆识别的样本自反馈式级联检测方法。方法兼具Adaboost级联检测器的架构优势和样本自反馈方法的样本扩充能力。通过前车图像的识别实例阐述了样本自反馈式级联检测方法的识别过程,进而使用常规Adaboost检测器和样本自反馈式级联检测方法对图像数据集进行了识别,将生产者精度、用户精度、总体识别精度、k值作为评价指标对识别效果进行了比较,证明了样本自反馈式级联检测方法具有较高的识别精度。分析了样本自反馈式级联检测方法个别评价指标较低的原因,提出了相应问题的解决思路。 相似文献
999.
《矿业科学技术学报(英文版)》2017,27(3):415-421
There are various analytical, empirical and numerical methods to calculate groundwater inflow into tunnels excavated in rocky media. Analytical methods have been widely applied in prediction of groundwater inflow to tunnels due to their simplicity and practical base theory. Investigations show that the real amount of water infiltrating into jointed tunnels is much less than calculated amount using analytical methods and obtained results are very dependent on tunnel‘s geometry and environmental situations.In this study, using multiple regression analysis, a new empirical model for estimation of groundwater seepage into circular tunnels was introduced. Our data was acquired from field surveys and laboratory analysis of core samples. New regression variables were defined after perusing single and two variables relationship between groundwater seepage and other variables. Finally, an appropriate model for estimation of leakage was obtained using the stepwise algorithm. Statistics like R, R~2, R_P~2 and the histogram of residual values in the model represent a good reputation and fitness for this model to estimate the groundwater seepage into tunnels. The new experimental model was used for the test data and results were satisfactory. Therefore, multiple regression analysis is an effective and efficient way to estimate the groundwater seepage into tunnels. 相似文献
1000.
为科学确定城市交通的发展规模,在分析关键交叉口转向能力的基础上,提出了基于超级节点的城市交通网络构建方法;考虑公交资源以及公交优先发展战略的因素,构建了城市交通发展规模与交通资源适应性的数学模型,并设计了基于反馈的免疫克隆算法.以城市内某一区域为例对模型和算法进行验证,结果表明:模型及算法具有较好的实用性,能够为城市交通规划部门提供良好的决策支持. 相似文献