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71.
In order to perform ontology matching with high accuracy, while at the same time retaining applicability to most diverse input ontologies, the matching process generally incorporates multiple methods. Each of these methods is aimed at a particular ontology component, such as annotations, structure, properties or instances. Adequately combining these methods is one of the greatest challenges in designing an ontology matching system. In a parallel composition of basic matchers, the ability to dynamically set the weights of the basic matchers in the final output, thus making the weights optimal for the given input, is the key breakthrough for obtaining first-rate matching performance. In this paper we present CroMatcher, an ontology matching system, introducing several novelties to the automated weight calculation process. We apply substitute values for matchers that are inapplicable for the particular case and use thresholds to eliminate low-probability alignment candidates. We compare the alignments produced by the matchers and give less weight to the matchers producing mutually similar alignments, whereas more weight is given to those matchers whose alignment is distinct and rather unique. We also present a new, iterative method for producing one-to-one final alignment of ontology structures, which is a significant enhancement of similar non-iterative methods proposed in the literature. CroMatcher has been evaluated against other state-of-the-art matching systems at the OAEI evaluation contest. In a large number of test cases it achieved the highest score, which puts it among the state-of-the-art leaders. 相似文献
72.
Joel E. Cohen 《技术计量学》2013,55(2):206-207
The experimental error variance in a response surface model with a block effect has traditionally been assumed to be constant. In some experimental situations, however, this variance may be different for the different blocks that compose the associated design. This article discusses the analysis of a response surface model with a random block effect and heterogeneous error variances among the blocks. The model includes interactions between the fixed polynomial effects and the block effect. Procedures for estimating and testing the fixed effects and the random effects in the model are described. In particular, ANOVA-based procedures for testing equality of the error variances and testing the random effects are introduced. 相似文献
73.
Alina Momot 《Expert Systems》2012,29(4):347-358
Averaging in the time domain may be used for noise attenuation in case of biomedical signals with a quasi‐cyclical character. Traditional arithmetic averaging technique assumes the constancy of the noise power cycle‐wise, however, most types of noise are not stationary and the variability of noise power is observed. It constitutes a motivation for using methods of weighted averaging, in particular Bayesian weighted averaging. This paper presents the computational study of Bayesian weighted averaging with traditional (sharp) and fuzzy partition of the input data in the presence of non‐stationary noise. There is presented the known empirical Bayesian weighted averaging method (EBWA), with the parameter p describing the probabilistic model, and its modification NBWA which eliminates the parameter. Both methods can be extended by partitioning of the input data. The performance of presented methods is experimentally evaluated for an analytical signal as well as a real ECG signal and compared with traditional arithmetic averaging method. However, the methods can be applied to any signal with a quasi‐cyclical character. The aim of the paper is to show the influence of the type of partition as well as the number of parts on the quality of the averaged signal. 相似文献
74.
A robust adaptive weighted constant modulus algorithm is proposed for blind equalization of wireless communication systems under impulsive noise environment. The influence of the impulsive noise is analyzed based on numerical analysis method. Then an adaptive weighted constant modulus algorithm is constructed to adaptively suppress impulsive noise. Theoretical analysis is provided to illustrate that the proposed algorithm has a robust equalization performance since the impulsive noise is adaptively suppressed. Moreover, the proposed algorithm has stable and quick convergence due to avoidance of large misadjuntment and adoption of large step size. Simulation results are presented to show the robust equalization performance and the fast convergence speed of the proposed algorithm under both impulsive noise and Gaussian noise environments. 相似文献
75.
本文结合青岛城域网的特点,讨论了部署QoS的相关问题,为下一步在城域网中承载多种业务提供了切合实际的参考。 相似文献
76.
以极限弯曲和扭转工况的加权应变能最小为目标函数,以设计区域的体积分数为约束,以设计区域的材料密度为设计变量,建立基于加权应变能的拓扑优化模型。并对某ATV车身进行拓扑优化设计,得到了结构的载荷传递路径,验证了该方法的可行性。 相似文献
77.
R. Noorossana A. Vaghefi M. Dorri 《Quality and Reliability Engineering International》2011,27(4):425-436
In some statistical process control (SPC) applications, it is assumed that a quality characteristic or a vector of quality characteristics of interest follows a univariate or multivariate normal distribution, respectively. However, in certain applications this assumption may fail to hold and could lead to misleading results. In this paper, we study the effect of non‐normality when the quality of a process or product is characterized by a linear profile. Skewed and heavy‐tailed symmetric non‐normal distributions are used to evaluate the non‐normality effect numerically. The results reveal that the method proposed by Kimtextitet al. (J. Qual. Technol. 2003; 35 :317–328) can be designed to be robust to non‐normality for both highly skewed and heavy‐tailed distributions. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
78.
Hyun Cheol Lee Daniel W. Apley 《Quality and Reliability Engineering International》2011,27(3):337-352
Residual‐based control charts for autocorrelated processes are known to be sensitive to time series modeling errors, which can seriously inflate the false alarm rate. This paper presents a design approach for a residual‐based exponentially weighted moving average (EWMA) chart that mitigates this problem by modifying the control limits based on the level of model uncertainty. Using a Bayesian analysis, we derive the approximate expected variance of the EWMA statistic, where the expectation is with respect to the posterior distribution of the unknown model parameters. The result is a relatively clean expression for the expected variance as a function of the estimated parameters and their covariance matrix. We use control limits proportional to the square root of the expected variance. We compare our approach to two other approaches for designing robust residual‐based EWMA charts and argue that our approach generally results in a more appropriate widening of the control limits. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
79.
地表温度与植被指数相关性的空间尺度特征——以重庆市为例 总被引:3,自引:0,他引:3
为了揭示植被改善城市热岛的量化关系,以重庆市主城区为例,在不同的尺度上分析了地表温度与归一化植被指数之间的相关性,分别从全局和局部出发分析了两者之间的线性关系.结果发现,在120m尺度上两者之间的相关性最强,空间相关场表明相关性在空间上呈现较强的异质性;全局普通线性回归和地理加权回归分析发现,两者之间没有显著的线性关系,这说明可能还存在其他多种因素的复杂影响. 相似文献
80.
Objective:The aim was to evaluate the role of whole body diffusion weighted imaging (WB-DWI) of magnetic resonance in the diagnosis and efficacy evaluation of malignant lymphoma.Methods: The clinical manifestation of whole body diffusion weighted imaging of 47 patients with malignant lymphoma being pathologically proved were carried on by retrospective analysis and to compare with 10 healthy volunteers.There were 8 cases of Hodgkin's lymphoma (HD) patients, of which WB-DWI examination of 5 cases were carried out before and after treatment and 3 cases were done after treatment.There were 39 cases of non-Hodgkin's lymphoma (NHL) patients, of which WB-DWI examination in 19 cases were acted before treatment, 11 cases were done before and after treatment and 9 cases done after treatment.In apparent diffusion coefficient (ADC) diagram the ADC values of lymph nodes in patients with malignant lymphoma and healthy volunteers were measured respectively, among 16 patients the ADC values of parts of lymph node being consistent with the initial inspection were determined again and compared the values before and after, and compared with healthy volunteers.Results: Whole body magnetic resonance diffusion weighted imaging (MR-DWI) showed more sensitive to lymphoma, and 372 lymph nodes greater than 1 cm were detected with MR-DWI.Before treatment, mean ADC value of 35 patients with malignant lymphoma was (0.86 0.21) × 10-3 mm2/s, of which an average ADC values of 28 cases after treatment was (1.22 0.31)× 10-3 mm2/s, before and after treatment difference of the average ADC values of patients was statistically significant (P < 0.05); the average ADC value of cervical lymph nodes of 10 healthy volunteers (1.29 0.12) × 10-3mm2/s and of 30 patients with malignant lymphoma before treatment was statistically significant (P < 0.05), and to compare with 28 patients after treatment difference of the ADC values was not statistically significant (P > 0.05).Conclusion: WB-DWI and ADC values being measured in the clinical diagnosis of malignant lymphoma, staging and evaluation of efficacy of monitoring is a fast and effective technology, with some clinical value. 相似文献