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Scientific data products and the data pre-processing subsystem of the Chang'e-3 mission 被引量:1
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作者 Xu Tan Jian-Jun Liu +7 位作者 Chun-Lai Li Jian-Qing Feng Xin Ren Fen-Fei Wang Wei Yan Wei Zuo Xiao-Qian Wang Zhou-Bin Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第12期1682-1694,共13页
The Chang'e-3 (CE-3) mission is China's first exploration mission on the surface of the Moon that uses a lander and a rover. Eight instruments that form the scientific payloads have the following objectives: (1... The Chang'e-3 (CE-3) mission is China's first exploration mission on the surface of the Moon that uses a lander and a rover. Eight instruments that form the scientific payloads have the following objectives: (1) investigate the morphological features and geological structures at the landing site; (2) integrated in-situ analysis of minerals and chemical compositions; (3) integrated exploration of the structure of the lunar interior; (4) exploration of the lunar-terrestrial space environment, lunar sur- face environment and acquire Moon-based ultraviolet astronomical observations. The Ground Research and Application System (GRAS) is in charge of data acquisition and pre-processing, management of the payload in orbit, and managing the data products and their applications. The Data Pre-processing Subsystem (DPS) is a part of GRAS. The task of DPS is the pre-processing of raw data from the eight instruments that are part of CE-3, including channel processing, unpacking, package sorting, calibration and correction, identification of geographical location, calculation of probe azimuth angle, probe zenith angle, solar azimuth angle, and solar zenith angle and so on, and conducting quality checks. These processes produce Level 0, Level 1 and Level 2 data. The computing platform of this subsystem is comprised of a high-performance computing cluster, including a real-time subsystem used for processing Level 0 data and a post-time subsystem for generating Level 1 and Level 2 data. This paper de- scribes the CE-3 data pre-processing method, the data pre-processing subsystem, data classification, data validity and data products that are used for scientific studies. 展开更多
关键词 Moon: data products -- methods: data pre-processing -- space vehicles:instruments
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Intelligent Data Pre-processing Model in Integrated Ocean Observing Network System
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作者 韩华 丁永生 刘凤鸣 《Journal of Donghua University(English Edition)》 EI CAS 2009年第5期499-502,共4页
There are a number of dirty data in observation data set derived from integrated ocean observing network system. Thus, the data must be carefully and reasonably processed before they are used for forecasting or analys... There are a number of dirty data in observation data set derived from integrated ocean observing network system. Thus, the data must be carefully and reasonably processed before they are used for forecasting or analysis. This paper proposes a data pre-processing model based on intelligent algorithms. Firstly, we introduce the integrated network platform of ocean observation. Next, the preprocessing model of data is presemed, and an imelligent cleaning model of data is proposed. Based on fuzzy clustering, the Kohonen clustering network is improved to fulfill the parallel calculation of fuzzy c-means clustering. The proposed dynamic algorithm can automatically f'md the new clustering center with the updated sample data. The rapid and dynamic performance of the model makes it suitable for real time calculation, and the efficiency and accuracy of the model is proved by test results through observation data analysis. 展开更多
关键词 integrated ocean observing network intelligentdata pre-processing data cleaning fuzzy soft clustering
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基于SP和RP数据融合的城市轨道交通选择模型 被引量:7
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作者 关宏志 王山川 +1 位作者 姚丽亚 易洪 《北京工业大学学报》 EI CAS CSCD 北大核心 2007年第2期203-207,共5页
针对SP数据存在的行为结果与意向结果不一致的问题,介绍了利用RP数据修正要SP数据的方法.以北京为例,建立了RP模型、SP模型和融合数据模型,并对模型的灵敏度进行了分析,结果表明,RP模型中费用变量的参数估计值符号与实际不符;SP数据模... 针对SP数据存在的行为结果与意向结果不一致的问题,介绍了利用RP数据修正要SP数据的方法.以北京为例,建立了RP模型、SP模型和融合数据模型,并对模型的灵敏度进行了分析,结果表明,RP模型中费用变量的参数估计值符号与实际不符;SP数据模型精度较高,但某些参数的影响不是很显著;融合数据模型的参数检验较显著,模型的弹性小,敏感性被钝化. 展开更多
关键词 轨道交通 rp数据 SP数据 非集计模型
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基于RP/SP联合数据的非集计模型应用研究 被引量:10
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作者 李军 朱顺应 +2 位作者 王红 李安勋 严新平 《铁道科学与工程学报》 CAS CSCD 北大核心 2007年第1期87-90,共4页
实际调查RP数据(Revealed preference Data)具有可靠性,而意向调查SP数据(Stated preference Data)具有灵活性。为了更好地将两类数据结合起来对新的交通方式进行预测,以长株潭城际轨道交通方式划分为例,介绍了数据的调查方法,利用正交... 实际调查RP数据(Revealed preference Data)具有可靠性,而意向调查SP数据(Stated preference Data)具有灵活性。为了更好地将两类数据结合起来对新的交通方式进行预测,以长株潭城际轨道交通方式划分为例,介绍了数据的调查方法,利用正交设计法对SP调查表格进行了设计。分别建立基于RP和SP数据的Logit模型,鉴于RP与SP模型中随机项的差异性,通过引入SP比例参数,构造RP/SP联合数据模型,并利用3种模型对未来的交通方式分担量进行了预测,最后对预测结果进行了比较分析。实例结果表明,基于RP/SP联合数据的logit模型能够平衡两类数据之间的误差相互影响,并能够得到更为合理的交通方式划分预测结果。 展开更多
关键词 rp/SP联合数据 非集计模型 方式划分 正交设计法
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RP/SP融合数据的Mixed Logit和Nested Logit模型估计对比 被引量:14
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作者 张天然 杨东援 +1 位作者 赵娅丽 叶亮 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2008年第8期1073-1078,1084,共7页
分析了RP/SP(revealed preference/stated preference)融合数据对交通行为研究的重要性,通过实际调查的RP/SP融合数据,对比了用Mixed Logit和Nested Logit模型的估计结果.得出了以下结论:RP/SP融合数据中,有时同类型交通方式的关联性要... 分析了RP/SP(revealed preference/stated preference)融合数据对交通行为研究的重要性,通过实际调查的RP/SP融合数据,对比了用Mixed Logit和Nested Logit模型的估计结果.得出了以下结论:RP/SP融合数据中,有时同类型交通方式的关联性要比RP和SP数据之间的关联性强,应用不同的Nested Logit模型分层方法进行估计对比;Mixed Logit考虑了个体的异质性,假定参数为随机分布,同时体现了RP/SP数据的关联性和同类型交通方式的关联性,能够得到更好的参数估计结果;Mixed Logit模型能更现实地反映不同交通方式使用者对时间和费用敏感性的不同(时间价值的不同),体现小汽车使用者比公共交通使用者具有更高时间价值的现实情况. 展开更多
关键词 rp/SP融合数据 MIXED Logit(rpL/RCL)模型 异质性 Nested LOGIT模型
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基于RP/SP融合数据的沪杭客运通道公铁客流分担率研究 被引量:16
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作者 张戎 吴晓磊 张天然 《铁道学报》 EI CAS CSCD 北大核心 2008年第3期7-13,共7页
RP(Revealed Preference)和SP(Stated Preference)调查是分析交通行为的两种重要方法,为充分利用两种数据的优点,研究运用NL(Nested Logit)模型进行RP/SP数据融合的方法。以沪杭客运通道修建磁浮铁路和客运专线为背景,设计RP/SP的调研方... RP(Revealed Preference)和SP(Stated Preference)调查是分析交通行为的两种重要方法,为充分利用两种数据的优点,研究运用NL(Nested Logit)模型进行RP/SP数据融合的方法。以沪杭客运通道修建磁浮铁路和客运专线为背景,设计RP/SP的调研方案;根据该通道客流特点建立RP/SP的效用函数;根据样本数据的RP/SP性质以及交通方式性质建立不同的NL数据融合模型,并分析模型的精度,得出利用NL模型建立的数据融合模型比单独利用RP或SP数据建立的ML(Multinomial Logit)模型精度要高,并且采用先按交通方式的性质分层,然后再按数据的RP/SP性质分层的3层NL模型精度更高的结论。在此基础上预测了2015年沪杭各类铁路及公路的客流分担率。 展开更多
关键词 客流分担率 SP/rp融合数据 Nested LOGIT模型 快速客运线
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基于STL模型的RP数据前置处理ASP工具集研究及应用 被引量:2
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作者 兰红波 丁玉成 +1 位作者 洪军 卢秉恒 《中国机械工程》 EI CAS CSCD 北大核心 2007年第5期559-563,共5页
提出一种基于STL模型的RP数据前置处理ASP解决方法,建立了ASP工具集的功能模型和体系结构;以STL文件的缺陷检查与模块修补为例,阐述了ASP工具集的具体开发过程,开发的ASP工具集已集成到RPM网络化服务集成系统中。应用结果表明,基于STL... 提出一种基于STL模型的RP数据前置处理ASP解决方法,建立了ASP工具集的功能模型和体系结构;以STL文件的缺陷检查与模块修补为例,阐述了ASP工具集的具体开发过程,开发的ASP工具集已集成到RPM网络化服务集成系统中。应用结果表明,基于STL模型的RP数据前置处理ASP工具集提供了一个有效的使能工具,在为协同制造企业和RP用户提供统一的前置数据处理和工艺选择服务的同时,可提供数据前置处理软件的维护、管理和升级服务,能有效地支持RPM网络化制造的实施。 展开更多
关键词 rpM ASP工具集 网络化服务 rp数据前置处理
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基于SP和RP融合数据的小汽车通勤出行频率选择模型 被引量:5
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作者 韩艳 关宏志 《公路交通科技》 CAS CSCD 北大核心 2011年第7期131-135,141,共6页
基于小汽车通勤出行特性和成本分析,采用意愿调查法对小汽车出行者的社会经济属性、通勤特性和不同燃油价格下的出行意向进行调查,定量分析停车位供应状况、停车费、燃油价格等因素对小汽车使用者通勤出行频率的影响,以获取高燃油价格... 基于小汽车通勤出行特性和成本分析,采用意愿调查法对小汽车出行者的社会经济属性、通勤特性和不同燃油价格下的出行意向进行调查,定量分析停车位供应状况、停车费、燃油价格等因素对小汽车使用者通勤出行频率的影响,以获取高燃油价格下小汽车通勤行为随燃油价格(出行成本)变化的规律。基于多项选择模型,分别建立了RP模型、SP模型和基于RP、SP数据融合的小汽车通勤出行频率选择模型。结果表明:融合数据模型的参数检验较显著。小汽车周通勤出行频率选择概率对燃油价格的弹性均小于1.0,缺乏弹性。小汽车通勤出行中低出行频率的燃油价格弹性明显高于高出行频率的燃油价格弹性,该群体的小汽车出行需求压缩空间较大。 展开更多
关键词 交通工程 出行频率选择模型 rp、SP融合数据 通勤交通 燃油价格
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RE&RP一体化技术在工业设计中的应用研究 被引量:1
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作者 蒋华 薛澄岐 《电子机械工程》 2009年第5期1-3,共3页
阐述了反求工程和快速成型的概念,论证了反求工程和快速成型技术一体化在现代工业设计中应用的意义和模式,并从扫描模型的建立、数据采集、数据处理、CAD模型的重建、产品的再设计与快速成型技术等方面,对反求工程和快速成型一体化具体... 阐述了反求工程和快速成型的概念,论证了反求工程和快速成型技术一体化在现代工业设计中应用的意义和模式,并从扫描模型的建立、数据采集、数据处理、CAD模型的重建、产品的再设计与快速成型技术等方面,对反求工程和快速成型一体化具体应用过程进行了比较详细的分析和研究。将反求工程与快速成型一体化技术应用于现代工业设计中,改变传统的产品开发设计、制造模式,从而大大缩短产品开发周期。 展开更多
关键词 快速成型技术 反求工程 数据处理
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RE/RP技术的现状及集成方式 被引量:4
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作者 董黎敏 刘霞 +1 位作者 茅波 吴大将 《组合机床与自动化加工技术》 2008年第7期1-5,共5页
文章简要介绍了RE/RP技术的基本概念及其发展概况,讨论了RE/RP的关键技术及特性。基于RE/RP产品开发流程,比较详细的探讨了RE/RP的集成方式,并指出每一种集成方式存在的不足,为以后RE/RP技术的提高奠定了基础。最后阐述了RE/RP技术的应... 文章简要介绍了RE/RP技术的基本概念及其发展概况,讨论了RE/RP的关键技术及特性。基于RE/RP产品开发流程,比较详细的探讨了RE/RP的集成方式,并指出每一种集成方式存在的不足,为以后RE/RP技术的提高奠定了基础。最后阐述了RE/RP技术的应用领域及发展趋势。 展开更多
关键词 RE/rp 关键技术 集成方式 应用领域 数据交换
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CNN coal and rock recognition method based on hyperspectral data 被引量:4
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作者 Jianjian Yang Boshen Chang +3 位作者 Yuchen Zhang Wenjie Luo Shirong Ge Miao Wu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2022年第5期59-70,共12页
Aiming at the problem of coal gangue identifcation in the current fully mechanized mining face and coal washing,this article proposed a convolution neural network(CNN)coal and rock identifcation method based on hypers... Aiming at the problem of coal gangue identifcation in the current fully mechanized mining face and coal washing,this article proposed a convolution neural network(CNN)coal and rock identifcation method based on hyperspectral data.First,coal and rock spectrum data were collected by a near-infrared spectrometer,and then four methods were used to flter 120 sets of collected data:frst-order diferential(FD),second-order diferential(SD),standard normal variable transformation(SNV),and multi-style smoothing.The coal and rock refectance spectrum data were pre-processed to enhance the intensity of spectral refectance and absorption characteristics,as well as efectively remove the spectral curve noise generated by instrument performance and environmental factors.A CNN model was constructed,and its advantages and disadvantages were judged based on the accuracy of the three parameter combinations(i.e.,the learning rate,the number of feature extraction layers,and the dropout rate)to generate the best CNN classifer for the hyperspectral data for rock recognition.The experiments show that the recognition accuracy of the one-dimensional CNN model proposed in this paper reaches 94.6%.Verifcation of the advantages and efectiveness of the method were proposed in this article. 展开更多
关键词 Hyperspectral data data pre-processing 1D-CNN Coal gangue identifcation
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RP/SP数据的Nested Logit同构融合
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作者 吾晨晨 吴戈 +1 位作者 李春艳 李先 《西华大学学报(自然科学版)》 CAS 2017年第2期61-67,共7页
在RP/SP融合分析中,当部分选项有一定相似性时,常用Nested Logit(NL)框架构建RP或SP子模型;但既有研究中,2个子模型往往采用不同的阶层结构,导致对行为机制的认识缺乏统一性、不同层次误差项对应关系不明确、无法正确描述SP选择的阶层... 在RP/SP融合分析中,当部分选项有一定相似性时,常用Nested Logit(NL)框架构建RP或SP子模型;但既有研究中,2个子模型往往采用不同的阶层结构,导致对行为机制的认识缺乏统一性、不同层次误差项对应关系不明确、无法正确描述SP选择的阶层性等问题。本文针对RP-NL/SP-NL的同构融合框架,提出分层考虑误差项测度、引入融合系数修正SP效用函数的融合方法,以北京市新设快速路公交专用道为对象进行问卷调查,标定和对比3种RP-NL/SP-NL模型及RP、SP单独模型的结果。研究表明:分层考虑SP与RP的误差项关系,可以更清晰地揭示SP数据的阶层结构,真实表现SP的选择机制,也有利于减小误差项的影响,提高变量对SP选择行为的解释能力。 展开更多
关键词 交通工程 rp/SP数据融合 Nested LOGIT模型 测度系数 融合系数 同构
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External calibration of GOCE data using regional terrestrial gravity data 被引量:4
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作者 Wu Yunlong Li Hui +1 位作者 Zou Zhengbo Kang Kaixuan 《Geodesy and Geodynamics》 2012年第3期34-39,共6页
This paper reports on a study of the methodology of external calibration of GOCE data,using regional terrestrial-gravity data.Three regions around the world are selected in the numerical experiments.The result indicat... This paper reports on a study of the methodology of external calibration of GOCE data,using regional terrestrial-gravity data.Three regions around the world are selected in the numerical experiments.The result indicates that this calibration method is feasible.The effect is best with an accuracy of scale factor at 10-2 level,in Australia,where the area is smooth and the gravity data points are dense.The accuracy is one order of magnitude lower in both Canada,where the area is smooth but the data points are sparse,and Norway,where the area is rather tough and the data points are sparse. 展开更多
关键词 satellite gravity gradiometer GOCE external calibration terrestrial gravity data pre-process
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Emotion Deduction from Social Media Text Data Using Machine Learning Algorithm
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作者 Thambusamy Velmurugan Baskaran Jayapradha 《Journal of Computer and Communications》 2023年第11期183-196,共14页
Emotion represents the feeling of an individual in a given situation. There are various ways to express the emotions of an individual. It can be categorized into verbal expressions, written expressions, facial express... Emotion represents the feeling of an individual in a given situation. There are various ways to express the emotions of an individual. It can be categorized into verbal expressions, written expressions, facial expressions and gestures. Among these various ways of expressing the emotion, the written method is a challenging task to extract the emotions, as the data is in the form of textual dat. Finding the different kinds of emotions is also a tedious task as it requires a lot of pre preparations of the textual data taken for the research. This research work is carried out to analyse and extract the emotions hidden in text data. The text data taken for the analysis is from the social media dataset. Using the raw text data directly from the social media will not serve the purpose. Therefore, the text data has to be pre-processed and then utilised for further processing. Pre-processing makes the text data more efficient and would infer valuable insights of the emotions hidden in it. The preprocessing steps also help to manage the text data for identifying the emotions conveyed in the text. This work proposes to deduct the emotions taken from the social media text data by applying the machine learning algorithm. Finally, the usefulness of the emotions is suggested for various stake holders, to find the attitude of individuals at that moment, the data is produced. . 展开更多
关键词 data pre-processing Machine Learning Algorithms Emotion Deduction Sentiment Analysis
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基于SP模型和RP数据融合的城市轨道交通选择模型设计
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作者 陈元静 《武汉理工大学学报(交通科学与工程版)》 2023年第4期620-623,共4页
文中基于SP模型和RP数据模型实现关于城市轨道交通选择模型设计的研究,探讨居民出行选择方式、选择行为关联性,了解居民出行方式选择的影响因素,验证分析相关模型的应用质量.结果表明:RP模型中费用变量参数估计值符号和实际不相符;SP数... 文中基于SP模型和RP数据模型实现关于城市轨道交通选择模型设计的研究,探讨居民出行选择方式、选择行为关联性,了解居民出行方式选择的影响因素,验证分析相关模型的应用质量.结果表明:RP模型中费用变量参数估计值符号和实际不相符;SP数据模型精度较高;融合数据模型与之相比弹性较小,敏感性被钝化. 展开更多
关键词 SP模型 rp数据 城市轨道 数据挖掘 选择模型设计
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Product quality prediction based on RBF optimized by firefly algorithm 被引量:3
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作者 HAN Huihui WANG Jian +1 位作者 CHEN Sen YAN Manting 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期105-117,共13页
With the development of information technology,a large number of product quality data in the entire manufacturing process is accumulated,but it is not explored and used effectively.The traditional product quality pred... With the development of information technology,a large number of product quality data in the entire manufacturing process is accumulated,but it is not explored and used effectively.The traditional product quality prediction models have many disadvantages,such as high complexity and low accuracy.To overcome the above problems,we propose an optimized data equalization method to pre-process dataset and design a simple but effective product quality prediction model:radial basis function model optimized by the firefly algorithm with Levy flight mechanism(RBFFALM).First,the new data equalization method is introduced to pre-process the dataset,which reduces the dimension of the data,removes redundant features,and improves the data distribution.Then the RBFFALFM is used to predict product quality.Comprehensive expe riments conducted on real-world product quality datasets validate that the new model RBFFALFM combining with the new data pre-processing method outperforms other previous me thods on predicting product quality. 展开更多
关键词 product quality prediction data pre-processing radial basis function swarm intelligence optimization algorithm
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Machine-Learning Based Packet Switching Method for Providing Stable High-Quality Video Streaming in Multi-Stream Transmission 被引量:1
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作者 Yumin Jo Jongho Paik 《Computers, Materials & Continua》 SCIE EI 2024年第3期4153-4176,共24页
Broadcasting gateway equipment generally uses a method of simply switching to a spare input stream when a failure occurs in a main input stream.However,when the transmission environment is unstable,problems such as re... Broadcasting gateway equipment generally uses a method of simply switching to a spare input stream when a failure occurs in a main input stream.However,when the transmission environment is unstable,problems such as reduction in the lifespan of equipment due to frequent switching and interruption,delay,and stoppage of services may occur.Therefore,applying a machine learning(ML)method,which is possible to automatically judge and classify network-related service anomaly,and switch multi-input signals without dropping or changing signals by predicting or quickly determining the time of error occurrence for smooth stream switching when there are problems such as transmission errors,is required.In this paper,we propose an intelligent packet switching method based on the ML method of classification,which is one of the supervised learning methods,that presents the risk level of abnormal multi-stream occurring in broadcasting gateway equipment based on data.Furthermore,we subdivide the risk levels obtained from classification techniques into probabilities and then derive vectorized representative values for each attribute value of the collected input data and continuously update them.The obtained reference vector value is used for switching judgment through the cosine similarity value between input data obtained when a dangerous situation occurs.In the broadcasting gateway equipment to which the proposed method is applied,it is possible to perform more stable and smarter switching than before by solving problems of reliability and broadcasting accidents of the equipment and can maintain stable video streaming as well. 展开更多
关键词 Broadcasting and communication convergence multi-stream packet switching advanced television systems committee standard 3.0(ATSC 3.0) data pre-processing machine learning cosine similarity
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基于数据扩充与无阈值递归图的非侵入式负荷识别方法 被引量:5
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作者 邢海青 郭瑞峰 +2 位作者 杨浙川 熊小雨 施永涛 《浙江电力》 2024年第6期88-100,共13页
非侵入式负荷监测技术不仅能将电能流向透明化,还能简化智能电表安装流程,从而有效降低负荷监测成本。为提高非侵入式负荷监测中的负荷识别准确性,提出了基于数据扩充与无阈值递归图的非侵入式负荷识别方法。采用去噪扩散概率模型对小... 非侵入式负荷监测技术不仅能将电能流向透明化,还能简化智能电表安装流程,从而有效降低负荷监测成本。为提高非侵入式负荷监测中的负荷识别准确性,提出了基于数据扩充与无阈值递归图的非侵入式负荷识别方法。采用去噪扩散概率模型对小样本负荷数据进行数据扩充,以提升负荷识别方法的鲁棒性;通过去除递归图的Heaviside函数实现无阈值递归图以高效表征负荷特征,并结合Transformer深度学习网络构建负荷识别框架。将所提出的方法应用到3个实测数据集中,实验结果表明,所提方法能有效提高负荷识别准确度,改善分类效果。 展开更多
关键词 非侵入式负荷监测 数据扩充 负荷识别 深度学习 递归图
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Review of Recent Trends in the Hybridisation of Preprocessing-Based and Parameter Optimisation-Based Hybrid Models to Forecast Univariate Streamflow
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作者 Baydaa Abdul Kareem Salah L.Zubaidi +1 位作者 Nadhir Al-Ansari Yousif Raad Muhsen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期1-41,共41页
Forecasting river flow is crucial for optimal planning,management,and sustainability using freshwater resources.Many machine learning(ML)approaches have been enhanced to improve streamflow prediction.Hybrid techniques... Forecasting river flow is crucial for optimal planning,management,and sustainability using freshwater resources.Many machine learning(ML)approaches have been enhanced to improve streamflow prediction.Hybrid techniques have been viewed as a viable method for enhancing the accuracy of univariate streamflow estimation when compared to standalone approaches.Current researchers have also emphasised using hybrid models to improve forecast accuracy.Accordingly,this paper conducts an updated literature review of applications of hybrid models in estimating streamflow over the last five years,summarising data preprocessing,univariate machine learning modelling strategy,advantages and disadvantages of standalone ML techniques,hybrid models,and performance metrics.This study focuses on two types of hybrid models:parameter optimisation-based hybrid models(OBH)and hybridisation of parameter optimisation-based and preprocessing-based hybridmodels(HOPH).Overall,this research supports the idea thatmeta-heuristic approaches precisely improveML techniques.It’s also one of the first efforts to comprehensively examine the efficiency of various meta-heuristic approaches(classified into four primary classes)hybridised with ML techniques.This study revealed that previous research applied swarm,evolutionary,physics,and hybrid metaheuristics with 77%,61%,12%,and 12%,respectively.Finally,there is still room for improving OBH and HOPH models by examining different data pre-processing techniques and metaheuristic algorithms. 展开更多
关键词 Univariate streamflow machine learning hybrid model data pre-processing performance metrics
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Hardware pre-processing for data of SBL underwater positioning system
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作者 HU Gozhi(Harbin Shipbuilding Engineering Insitute) 《Chinese Journal of Acoustics》 1990年第3期249-255,共7页
The synchro double pulse signal mode is freuqently used in Short Base Line (SBL)underwater positioning system so as to obtain the information of both distance and depth of a target simultaneously. Howerer, this signal... The synchro double pulse signal mode is freuqently used in Short Base Line (SBL)underwater positioning system so as to obtain the information of both distance and depth of a target simultaneously. Howerer, this signal mode also brings about ranging indistinctness resulting in a shorter positioning distance much less than that limited by the period of the synchro signal. This paper presents a hardware distance-gate data acquiring scheme. It puts the original data sent to the computer in order of ' direct first pulse- depth information pulse (or first pulse reflected by water surface )…' to guarantee the effective positioning distance of the system. It has the advantage of reducing the processing time of the computer thus ensuring the realtime functioning of the system. A figure of the orbit of an underwater moving target measured in practice is attached to the end of the paper. 展开更多
关键词 Hardware pre-processing for data of SBL underwater positioning system data
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