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SAX

SAX的相关文献在2000年到2023年内共计167篇,主要集中在自动化技术、计算机技术、无线电电子学、电信技术、信息与知识传播 等领域,其中期刊论文132篇、会议论文1篇、专利文献34篇;相关期刊85种,包括信息系统工程、太原师范学院学报(自然科学版)、科技信息等; 相关会议1种,包括第18届全国数据库学术会议等;SAX的相关文献由345位作者贡献,包括徐坚、朱才镇、海洋等。

SAX—发文量

期刊论文>

论文:132 占比:79.04%

会议论文>

论文:1 占比:0.60%

专利文献>

论文:34 占比:20.36%

总计:167篇

SAX—发文趋势图

SAX

-研究学者

  • 徐坚
  • 朱才镇
  • 海洋
  • 赵宁
  • 刘会超
  • 刘雨潇
  • 孙彧
  • 孙敦陆
  • 张庆礼
  • 张德明
  • 期刊论文
  • 会议论文
  • 专利文献

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    • 刘云鹏; 王权; 许自强; 刘一瑾; 和家慧; 韩帅
    • 摘要: 油色谱在线监测对于电力变压器的运行维护、健康状态分析具有重要意义,然而受监测设备异常、外界环境干扰、运行状态变化等因素影响,监测数据中难免存在不同类型的异常数据。为此,提出了一种基于多层架构的油中溶解气体数据清洗与异常识别方法。首先利用变分模态分解去除时间序列中的趋势项,结合3σ准则对时序数据中的噪声值、缺失值、暂时性迁移数据等进行异常识别;然后根据关联分析结果对可清洗的异常数据利用长短期记忆神经网络进行重构清洗;并结合时间序列分段以及改进SAX算法实现对时序数据中的趋势性异常状态检测。最后,结合实例分析表明本文所提方法能够实现异常数据的有效清洗以及对趋势异常状态的准确识别。
    • Lijuan Yan; Xiaotao Wu; Jiaqing Xiao
    • 摘要: Symbolic Aggregate approXimation (SAX) is an efficient symbolic representation method that has been widely used in time series data mining. Its major limitation is that it relies exclusively on the mean values of segmented time series to derive the symbols. So, many important features of time series are not considered, such as extreme value, trend, fluctuation and so on. To solve this issue, we propose in this paper an improved Symbolic Aggregate approXimation based on multiple features and Vector Frequency Difference (SAX_VFD). SAX_VFD discriminates between time series by adopting an adaptive feature selection method. Furthermore, SAX_VFD is endowed with a new distance that takes into account the vector frequency difference between the symbolic sequence. We demonstrate the utility of the SAX_VFD on the time series classification task. The experimental results show that the proposed method has a better performance in terms of accuracy and dimensionality reduction compared to the so far published SAX based reduction techniques.
    • 许建远
    • 摘要: 配网短信平台,是配网自动化一个重要的信息化支持系统,将配网SCADA系统产生的告警信息,编制成短信发给有关工作人员.本软件在此基础之上,利用台账系统维护的设备经纬度信息,在告警短信上附加地图标注信息.工作人员收到处理后的短信,点击即可调转到地图组件,并在地图上显示告警设备的标注及告警内容.本软件在处理短信的同时,将短信缓存到有关数据库表,实现了在PC端以WEB方式浏览实时短信、历史短信,以及对短信统计分析的展示.
    • 张玉龙; 段梦兰; 段礼祥; 张丛健
    • 摘要: 传统的时域、频域、时频域分析方法基于振动信号对整个序列时间点分析,忽略了其中一小段时间序列数据变化规律,没有考虑其波形特征,无法有效提取特征.鉴于此,提出了基于符号聚合近似算法(SAX)的故障特征提取方法.该方法对机械振动信号SAX符号化近似表示,之后通过一定长度滑动窗口确定符号串类型,统计符号串频数,作为特征值,最后排列各个特征值,归一化后得到向量,作为该数据样本的特征向量.该方法针对周期序列中一小段数据进行对比,描述其变化规律,挖掘内在信息,形成数据模态,然后对各类模态统计分析,有效提取了原始序列的变化趋势和信息特征,克服了现有方法的不足.对油田现场压缩机气阀振动数据分析处理,用SAX方法提取特征向量后输入网格优化的SVM分类器进行了训练分类,与基于信息熵的特征提取方法进行对比,两者故障分类准确率分别为81.25%和100%.分析结果表明:SAX特征提取方法可以准确有效地提取故障特征,具有更高的故障识别率,基于SAX算法的往复压缩机气阀故障诊断方法具有可行性.所得结论可为压缩机气阀故障信号的进一步分析提供参考.%The traditional analysis methods based on vibration signal in time,frequency and time-frequency domain focus on the whole time sequence,but ignore the change characteristic and waveform tendency in a part of sequence,thus making it ineffective in feature extraction.A new fault feature extraction method based on SAX algorithm is proposed.This method transforms mechanical vibration signal into SAX symbol representation,and then determines the symbol string type through a sliding window with a certain length.The symbol string frequency is counted as the eigenvalues,and then arranged and normalized to obtain the vector as the feature vector of data sample.The method analyzes the periodic sequence on the basis of a part of sequence,describes the change characteristic and waveform tendency and digs the intrinsic information to form a data modality.Then,the statistical analysis of various modalities is conducted to effectively extract the trend of the original sequence from qualitative and quantitative perspectives and information features,thus overcoming the shortcomings of existing methods.Vibration data of on-site compressor valve in oilfield were analyzed and processed.The feature vector was extracted using SAX method.The grid-optimized SVM classifier is input for training classification and analyzed using feature extraction method based on information entropy.The accuracy of fault classification was 81.25% and 100%,respectively.The analysis results show that the SAX feature extraction method can extract the fault features accurately and effectively,and has a higher fault recognition rate.The SAX algorithm based fault diagnosis method for gas valve on reciprocating compressor is feasible.The conclusions can provide references for further analysis of compressor signals.
    • 刘青云; 马文跃; 焦铬
    • 摘要: 嵌入式Web服务能充分利用Web服务技术实现异构平台的数据交互和应用集成,xml解析是Web服务中重要一环,设计一款Sax方式的轻量级C语言xml解析器EmbedSax,以事件为驱动,借助树节点信息,准确高效地从xml文档中提取Web服务兴趣内容和生成xml,并在嵌入式平台上实现和验证.实验结果表明,在同等解析条件下与常用Sax解析器相比具有更高解析效率,可为资源受限平台Web服务和xml解析技术应用提供一定参考.
    • 孙秀杰12; 唐君234; 陈文东2; 柯弥2; 胡巢凤4; 许瑞莲3; 田瑞军2
    • 摘要: 本文建立了一种基于强阳离子交换填料/强阴离子交换填料(SCX/SAX)混合填料的集成化蛋白质组学样品前处理方法.本工作将前期已发展的离心式集成化蛋白质组学样品前处理技术SISPROT中的SCX填料替换成SCX和SAX混合填料,以溶菌酶和牛血清白蛋白为模型蛋白,研究了3种pH(3,7.4,12)条件下蛋白质在SCX/SAX混合填料上的保留行为;应用BCA方法对SCX/SAX混合填料的比例进行了优化,并应用SDS-PAGE法对酶解步骤中pH变化引起的蛋白质丢失情况进行了系统的考察.实验结果发现,在pH 7.4条件下,质量比为1:1的SCX/SAX混合填料的富集效率最佳,蛋白质富集容量为180μg,是SCX填料富集容量的两倍左右;且酶解步骤的pH变化过程不会影响蛋白质在SCX/SAX混合填料上的保留.最后应用改进的SISPROT方法对少量肠癌组织样品进行了集成化蛋白质组学样品前处理和分析,并与传统的基于SCX填料的SISPROT方法进行了对比研究.结果表明,蛋白质鉴定量、特异性肽段数量和肽段谱图匹配数量均与基于SCX填料的SISPROT技术相当,证实了该方法作为蛋白质反应器的可靠性.鉴于该方法可以实现在生理pH条件下进行样品前处理,且显著提高了上样容量和减少了样品损失,该方法有望成为一种更为通用的集成化蛋白质组学样品前处理技术.
    • Ke Long; Yuhang Wu; Yufeng Gui
    • 摘要: As the cash register system gradually prevailed in shopping malls, detecting the abnormal status of the cash register system has gradually become a hotspot issue. This paper analyzes the transaction data of a shopping mall. When calculating the degree of data difference, the coefficient of variation is used as the attribute weight;the weighted Euclidean distance is used to calculate the degree of difference;and k-means clustering is used to classify different time periods. It applies the LOF algorithm to detect the outlier degree of transaction data at each time period, sets the initial threshold to detect outliers, deletes the outliers, and then performs SAX detection on the data set. If it does not pass the test, then it will gradually expand the outlying domain and repeat the above process to optimize the outlier threshold to improve the sensitivity of detection algorithm and reduce false positives.
    • 白堂博; 张来斌; 王旭铎; 段礼祥; 王金江
    • 摘要: 在利用关联规则进行故障信息挖掘时,需要将连续型数据离散化和区间化.离散化效果决定了关联规则挖掘的效果,传统的均匀区段划分法忽略了数据的分布特点,加权划分法和模糊指数法均存在权值选择问题.鉴于此,提出基于符号聚合近似(SAX)的关联规则挖掘方法.首先对振动信号进行特征提取,然后利用SAX方法自适应对特征值数据离散化,从而实现关联规则挖掘,进行故障分析和信息提取,最后利用挖掘结果进行故障诊断.转子故障模拟试验分析结果表明:与等宽度和等密度离散化方法相比,该方法可以更好地进行数据离散化,实现故障信息挖掘和诊断.基于SAX的关联规则挖掘方法对试验数据和真实设备之间的数据通用具有良好的鲁棒性,便于进行实际应用.%When mining fault information using association rule,consecutive data need to be discretized and regionalized.The result of association rule mining is determined by the effect of discretization.Traditional uniform partitioning approach neglects the distribution characteristics of data,and both weighted partitioning methods and fuzzy index method have the problem of choosing weight values.To address the issue,association rule mining method based on SAX is proposed.Firstly,feature extraction on vibration signals is conducted,and then the characteristic value of the data are discretized adaptively by SAX,thus,association rule mining can be realized to conduct fault analysis and information extraction.Fault diagnosis could be done using mining results.The analysis results of rotor fault simulation experiment showed that,compared with equal density and equal width discretized approach,the proposed method could carry out a better data discretization and realize mining and diagnosis of fault information.The SAX method has good robustness to the experiment data and the real equipment data,and is convenient for practical application.
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