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31.
郭皎  鄢沛 《计算机应用与软件》2008,25(3):111-113,148
异构Web Services间的无缝互操作是成功构建基于Web Services应用的关键之一.讨论了Web Services互操作性概要和Web Services基本交互模式,详细分析了Web Services互操作原理和Web Services描述;说明了Web Services的类型定义中的类型不匹配、不可用类型、精度和值/引用类型等问题对互操作性的影响,并给出了处理方案;同时还分析了在Web Services的调用过程中采用的SOAP编码和消息模式、Web Services约束等问题.最后针对当前应用较广泛J2EE和.NET的两个平台的Web Services的互操作设计作了简要设计.  相似文献   
32.
电力市场的逐步开放以及大量可再生能源的接入使用户具有更多的用电自由,导致电力用户类型多样化、用户间负荷特性差异逐渐增大、负荷数据的类簇分布情况复杂化。为解决传统聚类算法面对不均衡负荷数据集时聚类效果不佳以及缺乏自适应能力等问题,提出一种改进自适应密度峰值聚类(Improved self-adaptive Density Peak Clustering,ISDPC)算法。首先,基于K-最近邻(K-Nearest Neighbor,KNN)和相对密度的思想定义了一种新的密度度量方式。然后在决策图中拟合分段函数得到最优类簇数目。最后,通过构造加权KNN图改进样本分配策略。试验结果表明,与传统聚类算法相比,所提方法聚类结果更加精确、具备自适应能力、鲁棒性更强。  相似文献   
33.
Process monitoring and fault diagnosis using profile data remains an important and challenging problem in statistical process control (SPC). Although the analysis of profile data has been extensively studied in the SPC literature, the challenges associated with monitoring and diagnosis of multichannel (multiple) nonlinear profiles are yet to be addressed. Motivated by an application in multioperation forging processes, we propose a new modeling, monitoring, and diagnosis framework for phase-I analysis of multichannel profiles. The proposed framework is developed under the assumption that different profile channels have similar structure so that we can gain strength by borrowing information from all channels. The multidimensional functional principal component analysis is incorporated into change-point models to construct monitoring statistics. Simulation results show that the proposed approach has good performance in identifying change-points in various situations compared with some existing methods. The codes for implementing the proposed procedure are available in the supplementary material.  相似文献   
34.
Change point estimation is a useful concept that helps quality engineers to effectively search for assignable causes and improve quality of the process or product. In this paper, the maximum likelihood approach is developed to estimate change point in the mean of multivariate linear profiles in Phase II. After the change point, parameters are estimated through filtering and smoothing approaches in dynamic linear model. The proposed change point estimator can be applied without any prior knowledge about the change type against existing estimators which assume change type is known in advance. Besides, sporadic change point can be identified as well. Simulation results show the effectiveness of the proposed estimators to estimate step, drift and monotonic, as well as sporadic changes in small to large shifts. In addition, effect of different values of the Multivariate Exponentially Weighted Moving Average (MEWMA) control chart smoothing coefficient on the performance of the proposed estimator is investigated presenting that the smoothing estimator has more uniform performance. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
35.
The exponentially weighted moving average (EWMA) model has been successfully used in acceptance sampling plans. The EWMA model provides the quality information of the current lot and the preceding lots. In addition, a multiple dependent state (MDS) sampling plan considers the quality information of the preceding lots. In this study, we present two new sampling plans for linear profiles. One is based on EWMA model with yield index using the single sampling plan, and the other is based on EWMA model with yield index using the MDS sampling plans. The plan parameters are determined by a nonlinear optimization approach. As the smoothing parameter value equals to one, the first proposed plan becomes the traditional single sampling plan. In addition, we compare the proposed plans with the traditional single sampling plan. The results indicate that the MDS sampling plan based on EWMA model with yield index with smaller value of smoothing parameter performs better than the traditional single sampling plan and the single sampling plan based on EWMA model with yield index in terms of the sample size required. One real example is used to illustrate the proposed plan. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
36.
In this study, we propose the multiple comparisons with the best method based on the yield index to compare the process yields of K (K ≥ 2) suppliers for linear profiles with one‐sided specifications. The performance analysis of the proposed method is conducted. The numbers of profiles required for different power levels are also provided. A simulated data set from a leather dyeing process is presented to illustrate the applicability of the proposed method. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
37.
The new investigation of profile monitoring is focused mainly on a process with multiple quality characteristics. Process yield has been used widely in the manufacturing industry, as an index for measuring process capability. In this study, we present two indices and to measure the process capability for multivariate linear profiles with one‐sided specification limits under mutually independent normality. Additionally, two indices and are proposed to measure the process capability for multivariate linear profiles with one‐sided specification limits under multivariate normality. These indices can provide an exact measure of the process yield. The approximate normal distributions for and are constructed. A simulation study is conducted to assess the performance of the proposed approach. The simulation results show that the estimated value of performs better as the number of profiles increases. Two illustrative examples are used to demonstrate the applicability of the proposed approach. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
38.
The concept of elementary flux vector is valuable in a number of applications of metabolic engineering. For instance, in metabolic flux analysis, each admissible flux vector can be expressed as a non-negative linear combination of a small number of elementary flux vectors. However a critical issue concerns the total number of elementary flux vectors which may be huge because it combinatorially increases with the size of the metabolic network. In this paper we present a fast algorithm that randomly computes a decomposition of admissible flux vectors in a minimal number of elementary flux vectors without explicitly enumerating all of them.  相似文献   
39.
随着大规模基因表达谱技术的发展,基于基因表达谱的癌症诊断方法正在成为临床医学上一种快速有效的诊断方法,但是由于基因表达数据维数过高、样本量小、噪声大,使得正确提取有关癌症的特征基因成为关键。以结肠癌肿瘤的基因表达谱数据为例,提出了结合Fisher权函数、离散傅里叶变换和主成分分析的混合特征基因提取方法,以多元Logistic回归分析和贝叶斯决策作为分类器进行肿瘤分类检测。实验结果表明,该方法对于结肠癌数据集CV识别准确率高达96.80%。  相似文献   
40.
基于概念扩充的中文文本过滤模型   总被引:8,自引:0,他引:8  
1 前言今天,以因特网为主体的信息高速公路仍在不断普及和发展,因特网上蕴涵的海量信息远远超过人们的想象,面对这样的信息汪洋大海,人们往往感到束手无策,无所适从,出现所谓的“信息过载”问题。如何帮助人们有效地选择和利用所感兴趣的信息,同时保证人们在信息选择方面的个人隐私权利?这已成为学术界和企业界所十分关注的焦点。因此,信息过滤技术应  相似文献   
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