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Prediction of Lubricant Physicochemical Properties Based on Gaussian Copula Data Expansion
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作者 Feng Xin Yang Rui +1 位作者 Xie Peiyuan Xia Yanqiu 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第1期161-174,共14页
The composition of base oils affects the performance of lubricants made from them.This paper proposes a hybrid model based on gradient-boosted decision tree(GBDT)to analyze the effect of different ratios of KN4010,PAO... The composition of base oils affects the performance of lubricants made from them.This paper proposes a hybrid model based on gradient-boosted decision tree(GBDT)to analyze the effect of different ratios of KN4010,PAO40,and PriEco3000 component in a composite base oil system on the performance of lubricants.The study was conducted under small laboratory sample conditions,and a data expansion method using the Gaussian Copula function was proposed to improve the prediction ability of the hybrid model.The study also compared four optimization algorithms,sticky mushroom algorithm(SMA),genetic algorithm(GA),whale optimization algorithm(WOA),and seagull optimization algorithm(SOA),to predict the kinematic viscosity at 40℃,kinematic viscosity at 100℃,viscosity index,and oxidation induction time performance of the lubricant.The results showed that the Gaussian Copula function data expansion method improved the prediction ability of the hybrid model in the case of small samples.The SOA-GBDT hybrid model had the fastest convergence speed for the samples and the best prediction effect,with determination coefficients(R^(2))for the four indicators of lubricants reaching 0.98,0.99,0.96 and 0.96,respectively.Thus,this model can significantly reduce the model’s prediction error and has good prediction ability. 展开更多
关键词 base oil data augmentation machine learning performance prediction seagull algorithm
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Blockchain-Based Cognitive Computing Model for Data Security on a Cloud Platform 被引量:1
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作者 Xiangmin Guo Guangjun Liang +1 位作者 Jiayin Liu Xianyi Chen 《Computers, Materials & Continua》 SCIE EI 2023年第12期3305-3323,共19页
Cloud storage is widely used by large companies to store vast amounts of data and files,offering flexibility,financial savings,and security.However,information shoplifting poses significant threats,potentially leading... Cloud storage is widely used by large companies to store vast amounts of data and files,offering flexibility,financial savings,and security.However,information shoplifting poses significant threats,potentially leading to poor performance and privacy breaches.Blockchain-based cognitive computing can help protect and maintain information security and privacy in cloud platforms,ensuring businesses can focus on business development.To ensure data security in cloud platforms,this research proposed a blockchain-based Hybridized Data Driven Cognitive Computing(HD2C)model.However,the proposed HD2C framework addresses breaches of the privacy information of mixed participants of the Internet of Things(IoT)in the cloud.HD2C is developed by combining Federated Learning(FL)with a Blockchain consensus algorithm to connect smart contracts with Proof of Authority.The“Data Island”problem can be solved by FL’s emphasis on privacy and lightning-fast processing,while Blockchain provides a decentralized incentive structure that is impervious to poisoning.FL with Blockchain allows quick consensus through smart member selection and verification.The HD2C paradigm significantly improves the computational processing efficiency of intelligent manufacturing.Extensive analysis results derived from IIoT datasets confirm HD2C superiority.When compared to other consensus algorithms,the Blockchain PoA’s foundational cost is significant.The accuracy and memory utilization evaluation results predict the total benefits of the system.In comparison to the values 0.004 and 0.04,the value of 0.4 achieves good accuracy.According to the experiment results,the number of transactions per second has minimal impact on memory requirements.The findings of this study resulted in the development of a brand-new IIoT framework based on blockchain technology. 展开更多
关键词 Blockchain Internet of Things(IoT) blockchain based cognitive computing Hybridized data Driven Cognitive Computing(HD2C) Federated Learning(FL) Proof of Authority(PoA)
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Creating Bengali Freebase Using Wikidata
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作者 Rukaiya Habib Mahmuda Ferdous Md Musfique Anwar 《Journal of Computer and Communications》 2023年第5期151-160,共10页
Freebase is a large collaborative knowledge base and database of general, structured information for public use. Its structured data had been harvested from many sources, including individual, user-submitted wiki cont... Freebase is a large collaborative knowledge base and database of general, structured information for public use. Its structured data had been harvested from many sources, including individual, user-submitted wiki contributions. Its aim is to create a global resource so that people (and machines) can access common information more effectively which is mostly available in English. In this research work, we have tried to build the technique of creating the Freebase for Bengali language. Today the number of Bengali articles on the internet is growing day by day. So it has become a necessary to have a structured data store in Bengali. It consists of different types of concepts (topics) and relationships between those topics. These include different types of areas like popular culture (e.g. films, music, books, sports, television), location information (restaurants, geolocations, businesses), scholarly information (linguistics, biology, astronomy), birth place of (poets, politicians, actor, actress) and general knowledge (Wikipedia). It will be much more helpful for relation extraction or any kind of Natural Language Processing (NLP) works on Bengali language. In this work, we identified the technique of creating the Bengali Freebase and made a collection of Bengali data. We applied SPARQL query language to extract information from natural language (Bengali) documents such as Wikidata which is typically in RDF (Resource Description Format) triple format. 展开更多
关键词 KNOWLEDGE-base Structured data NLP RDF
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基于改进DBSCAN和距离共识评估的分段点云去噪方法
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作者 葛程鹏 赵东 +1 位作者 王蕊 马庆华 《系统仿真学报》 CAS CSCD 北大核心 2024年第8期1800-1809,共10页
针对点云数据中噪声点的剔除问题,提出了一种基于改进DBSCAN(density-based spatial clustering of applications with noise)算法的多尺度点云去噪方法。应用统计滤波对孤立离群点进行预筛选,去除点云中的大尺度噪声;对DBSCAN算法进行... 针对点云数据中噪声点的剔除问题,提出了一种基于改进DBSCAN(density-based spatial clustering of applications with noise)算法的多尺度点云去噪方法。应用统计滤波对孤立离群点进行预筛选,去除点云中的大尺度噪声;对DBSCAN算法进行优化,减少算法时间复杂度和实现参数的自适应调整,以此将点云分为正常簇、疑似簇及异常簇,并立即去除异常簇;利用距离共识评估法对疑似簇进行精细判定,通过计算疑似点与其最近的正常点拟合表面之间的距离,判定其是否为异常,有效保持了数据的关键特征和模型敏感度。利用该方法对两个船体分段点云进行去噪,并与其他去噪算法进行对比,结果表明,该方法在去噪效率和特征保持方面具有优势,精确地保留了点云数据的几何特性。 展开更多
关键词 点云去噪 点云数据 dbSCAN(density-based spatial clustering of applications with noise)聚类 距离共识评估 特征保持
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原料性质大幅变化情况下催化重整Delta-Base数据的生成方法
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作者 宋雨雨 吕文进 +2 位作者 崔晨 宋建 周祥 《石油炼制与化工》 CAS CSCD 北大核心 2024年第8期157-163,共7页
针对催化重整原料性质变化幅度较大的情况,提出采用变步长计算结合分子水平机理模型生成装置Delta-Base数据的方法。该方法通过计算原料性质扰动时产品质量分数变化量绝对值随原料性质变化量绝对值的变化率;并将该变化率的值域分成若干... 针对催化重整原料性质变化幅度较大的情况,提出采用变步长计算结合分子水平机理模型生成装置Delta-Base数据的方法。该方法通过计算原料性质扰动时产品质量分数变化量绝对值随原料性质变化量绝对值的变化率;并将该变化率的值域分成若干等份,根据每次计算得到变化率值域的范围不同,选择下一步计算时的变量扰动步长;继而在计算过程中取每次变量扰动的中点值产品质量分数进行验证,从而在提高计算效率的同时保证了计算结果的准确性。结果表明:利用该方法计算得到的各产品质量分数相对误差较小,基本不超过2.5%;对计算数据拟合可得到不同产品质量分数数据拟合方程,通过拟合方程可生成芳烃潜含量变化三阶段Delta-Base数据;比较原料芳烃潜含量(w)为42%时的产品预测结果,发现Delta-Base数据预测值和拟合方程计算值的平均偏差均为0.16%,说明该方法具有很好的准确性,利用分子水平机理模型生成的Delta-Base数据更能反映真实的分子反应历程。 展开更多
关键词 催化重整 分子水平模型 线性规划 Delta-base数据
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Data Conversion Among Different Databases Under an Integrated Network Environment 被引量:2
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作者 梁允荣 高玮玲 杨茜 《Journal of Beijing Institute of Technology》 EI CAS 2001年第2期209-214,共6页
Method for data conversion of heterogeneous DBMS's in the integrated network environment is introduced. The technical approach used can perform data conversion of heterogeneous databases located on different nodes... Method for data conversion of heterogeneous DBMS's in the integrated network environment is introduced. The technical approach used can perform data conversion of heterogeneous databases located on different nodes of the network, such as Oracle, Sybase, Informix, MS SQL Server, SQL Anywhere and Foxpro. The conversion system adopts the Client/Server architecture and provides visual integrated interface for users. 展开更多
关键词 heterogeneous db data conversion CLIENT/SERVER visual interface
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dBASEⅢ与外部接口间数据传递的通用方法
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作者 郑晓薇 《辽宁师范大学学报(自然科学版)》 CAS 1992年第3期206-210,共5页
根据由dBASEⅢ数据库在计算机内部的存储形式,描述了数据库与外部接口间直接数据传递的通用方法,并提出了一种通用程序加以实现.
关键词 库结构描述段 系统说明段 各字段说明段 外部接口 直接读取
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TP80共享 BCM—Ⅲ的 DBASE—Ⅱ数据库
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作者 杭柏林 《吉林化工学院学报》 CAS 1989年第4期64-67,共4页
本文讨论了TP801在局域网中共享DBASEⅡ数据库的一种方法.以提高计算机资源的利用率和单板机TP801的功能,为生产过程参数的实时打印报表提供了一个实用工具。
关键词 共享 网络系统 Dbase-Ⅱ 数据库
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DBASEⅢ中数值算法的实现
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作者 王彦祺 佟丽华 《河北地质学院学报》 1996年第1期66-69,共4页
DBASEⅢ,是一个数据库管理系统,但在数值计算上很弱,本文举出一些实例说明如何在DBASEⅢ上实现数值计算上一些典型算法,同时也给出DBASEⅢ的一些编程技巧。
关键词 Dbase 数据库管理系统 数值算法 递归
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缸套活塞环设计专家系统的知识获取和知识库建设(Ⅱ)─—dBASEⅢ支撑数据库及其同GCLISP语言的数据接口技术
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作者 缪毅 尹力 《重庆交通学院学报》 1996年第4期113-118,共6页
建造机械设计专家系统支撑数据库应着重解决好两个问题:对大量数据的维护和利用.本文采用dBASEⅢ建造机械设计专家系统的支撑数据库管理系统,并通过FORTRTAN程序设计语言实现dBASEⅢ支撑数据库同IBM-PC计算... 建造机械设计专家系统支撑数据库应着重解决好两个问题:对大量数据的维护和利用.本文采用dBASEⅢ建造机械设计专家系统的支撑数据库管理系统,并通过FORTRTAN程序设计语言实现dBASEⅢ支撑数据库同IBM-PC计算机人工智能程序设计语言GCLISP的数据接口,较好地解决了这两个问题. 展开更多
关键词 活塞环 设计 专家系统 汽车发动机 气缸套
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BASIC FORTRAN直接读取dBASEⅡ地震目录数据库文件的几种方法
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作者 许俊奇 《山西地震》 1992年第2期56-64,共9页
介绍了用BASIC、FORTRAN直接读取已知dBASEⅡ地震目录数据库文件的几种简便方法,并根据dBASEⅡ全国4级以上地震目录数据库文件的结构,给出了相应的BASIC、FORTRAN源程序。
关键词 文件 数据库 地震 目录 BASIC
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“Deep-time Digital Basin” Based on Big Data and Artificial Intelligence 被引量:2
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作者 FENG Zhiqing LIAN Peiqing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第S01期14-16,共3页
1 Introduction Information technology has been playing an ever-increasing role in geoscience.Sphisicated database platforms are essential for geological data storage,analysis and exchange of Big Data(Feblowitz,2013;Zh... 1 Introduction Information technology has been playing an ever-increasing role in geoscience.Sphisicated database platforms are essential for geological data storage,analysis and exchange of Big Data(Feblowitz,2013;Zhang et al.,2016;Teng et al.,2016;Tian and Li,2018).The United States has built an information-sharing platform for state-owned scientific data as a national strategy. 展开更多
关键词 deep-time DIGITAL earth(DDE) deep-time DIGITAL basin(Ddb) BIG data artificial intelligent knowledge base
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Data Mining and Neural Network Techniques in Case Based System 被引量:2
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作者 Ni Zhi wei 1,2 , Cai Qing sheng 1, Li Long shu 2 1.Department of Computer Science, University of Science and Technology of China,Hefei 230027,China 2.The Key Laboratory of Intelligent Computing and Signal Processing ,Ministry of Education 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期601-605,共5页
This paper first puts forward a case based system framework based on data mining techniques. Then the paper examines the possibility of using neural networks as a method of retrieval in such a case based system. In ... This paper first puts forward a case based system framework based on data mining techniques. Then the paper examines the possibility of using neural networks as a method of retrieval in such a case based system. In this system we propose data mining algorithms to discover case knowledge and other algorithms. 展开更多
关键词 data mining neural network case based reasoning retrieval algorithm
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Fast Web - Based Data Transmission 被引量:2
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作者 Wei Zukuan Department of Computer Science & Engineering, Inha University, Inchon 402 751, Korea Kim Jaehong Department of Computer Science, Youngdong University, Youngdong, Korea Bae Haeyoung Department of Computer Science & Engineering, Inha Uni 《Journal of China University of Geosciences》 SCIE CSCD 2001年第2期165-176,共12页
Since web based GIS processes large size spatial geographic information on internet, we should try to improve the efficiency of spatial data query processing and transmission. This paper presents two efficient metho... Since web based GIS processes large size spatial geographic information on internet, we should try to improve the efficiency of spatial data query processing and transmission. This paper presents two efficient methods for this purpose: division transmission and progressive transmission methods. In division transmission method, a map can be divided into several parts, called “tiles”, and only tiles can be transmitted at the request of a client. In progressive transmission method, a map can be split into several phase views based on the significance of vertices, and a server produces a target object and then transmits it progressively when this spatial object is requested from a client. In order to achieve these methods, the algorithms, “tile division”, “priority order estimation” and the strategies for data transmission are proposed in this paper, respectively. Compared with such traditional methods as “map total transmission” and “layer transmission”, the web based GIS data transmission, proposed in this paper, is advantageous in the increase of the data transmission efficiency by a great margin. 展开更多
关键词 spatial data transmission spatial query processing web based GIS geographic information system spatial database.
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A Path-Based Approach for Data Aggregation in Grid-Based Wireless Sensor Networks 被引量:1
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作者 Neng-Chung Wang Yung-Kuei Chiang Chih-Hung Hsieh 《Journal of Electronic Science and Technology》 CAS 2014年第3期313-317,共5页
Sensor nodes in a wireless sensor network (WSN) are typically powered by batteries, thus the energy is constrained. It is our design goal to efficiently utilize the energy of each sensor node to extend its lifetime,... Sensor nodes in a wireless sensor network (WSN) are typically powered by batteries, thus the energy is constrained. It is our design goal to efficiently utilize the energy of each sensor node to extend its lifetime, so as to prolong the lifetime of the whole WSN. In this paper, we propose a path-based data aggregation scheme (PBDAS) for grid-based wireless sensor networks. In order to extend the lifetime of a WSN, we construct a grid infrastructure by partitioning the whole sensor field into a grid of cells. Each cell has a head responsible for aggregating its own data with the data sensed by the others in the same cell and then transmitting out. In order to efficiently and rapidly transmit the data to the base station (BS), we link each cell head to form a chain. Each cell head on the chain takes turn becoming the chain leader responsible for transmitting data to the BS. Aggregated data moves from head to head along the chain, and finally the chain leader transmits to the BS. In PBDAS, only the cell heads need to transmit data toward the BS. Therefore, the data transmissions to the BS substantially decrease. Besides, the cell heads and chain leader are designated in turn according to the energy level so that the energy depletion of nodes is evenly distributed. Simulation results show that the proposed PBDAS extends the lifetime of sensor nodes, so as to make the lifetime of the whole network longer. 展开更多
关键词 base station cell head data aggregation grid-based wireless sensor networks
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The 8×10 GHz Receiver Optical Subassembly Based on Silica Hybrid Integration Technology for Data Center Interconnection 被引量:3
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作者 Chao-Yi Li Jun-Ming An +8 位作者 Jiu-Qi Wang Liang-Liang Wang Jia-Shun Zhang Jian-Guang Li Yuan-Da Wu Yue Wang Xiao-Jie Yin Yong Li Fei Zhong 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第10期39-43,共5页
An 8×10 GHz receiver optical sub-assembly (ROSA) consisting of an 8-channel arrayed waveguide grating (AWG) and an 8-channel PIN photodetector (PD) array is designed and fabricated based on silica hybrid in... An 8×10 GHz receiver optical sub-assembly (ROSA) consisting of an 8-channel arrayed waveguide grating (AWG) and an 8-channel PIN photodetector (PD) array is designed and fabricated based on silica hybrid integration technology. Multimode output waveguides in the silica AWG with 2% refractive index difference are used to obtain fiat-top spectra. The output waveguide facet is polished to 45° bevel to change the light propagation direction into the mesa-type PIN PD, which simplifies the packaging process. The experimentM results show that the single channel I dB bandwidth of AWG ranges from 2.12nm to 3.06nm, the ROSA responsivity ranges from 0.097 A/W to 0.158A/W, and the 3dB bandwidth is up to 11 GHz. It is promising to be applied in the eight-lane WDM transmission system in data center interconnection. 展开更多
关键词 AWG GHz Receiver Optical Subassembly based on Silica Hybrid Integration Technology for data Center Interconnection The 8 PD
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Proposed Caching Scheme for Optimizing Trade-off between Freshness and Energy Consumption in Name Data Networking Based IoT 被引量:1
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作者 Rahul Shrimali Hemal Shah Riya Chauhan 《Advances in Internet of Things》 2017年第2期11-24,共14页
Over the last few years, the Internet of Things (IoT) has become an omnipresent term. The IoT expands the existing common concepts, anytime and anyplace to the connectivity for anything. The proliferation in IoT offer... Over the last few years, the Internet of Things (IoT) has become an omnipresent term. The IoT expands the existing common concepts, anytime and anyplace to the connectivity for anything. The proliferation in IoT offers opportunities but may also bear risks. A hitherto neglected aspect is the possible increase in power consumption as smart devices in IoT applications are expected to be reachable by other devices at all times. This implies that the device is consuming electrical energy even when it is not in use for its primary function. Many researchers’ communities have started addressing storage ability like cache memory of smart devices using the concept called—Named Data Networking (NDN) to achieve better energy efficient communication model. In NDN, memory or buffer overflow is the common challenge especially when internal memory of node exceeds its limit and data with highest degree of freshness may not be accommodated and entire scenarios behaves like a traditional network. In such case, Data Caching is not performed by intermediate nodes to guarantee highest degree of freshness. On the periodical updates sent from data producers, it is exceedingly demanded that data consumers must get up to date information at cost of lease energy. Consequently, there is challenge in maintaining tradeoff between freshness energy consumption during Publisher-Subscriber interaction. In our work, we proposed the architecture to overcome cache strategy issue by Smart Caching Algorithm for improvement in memory management and data freshness. The smart caching strategy updates the data at precise interval by keeping garbage data into consideration. It is also observed from experiment that data redundancy can be easily obtained by ignoring/dropping data packets for the information which is not of interest by other participating nodes in network, ultimately leading to optimizing tradeoff between freshness and energy required. 展开更多
关键词 Internet of Things (IoT) Named data NETWORKING Smart CACHING Table Pending INTEREST Forwarding INFORMATION base CONTENT Store CONTENT Centric NETWORKING INFORMATION Centric NETWORKING data & INTEREST Packets SCTSmart CACHING
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应用dBASEⅢ与Lotus-123微机程序对坐肺流调资料进行直观分析方法
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作者 肖芳 谭大刚 +2 位作者 陈培庆 马明学 徐跃平 《中国工业医学杂志》 CAS 1990年第1期19-21,65,共4页
本文介绍了用微机dBASE Ⅲ命令程序对沈阳市2 065名各期尘肺病人的逐年诊断、死亡人数及Ⅰ期尘肺病人病种分布情况进行分析的方法,并介绍了将该分析结果传送到Lotus-123绘制出各种图形方法。
关键词 dbaseⅢ数据库 Lotus-123软件 尘肺
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Optimal Tracking Control for a Class of Unknown Discrete-time Systems with Actuator Saturation via Data-based ADP Algorithm 被引量:4
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作者 SONG Rui-Zhuo XIAO Wen-Dong SUN Chang-Yin 《自动化学报》 EI CSCD 北大核心 2013年第9期1413-1420,共8页
为有致动器浸透和未知动力学的分离时间的系统的一个班的一个新奇最佳的追踪控制方法在这份报纸被建议。计划基于反复的适应动态编程(自动数据处理) 算法。以便实现控制计划,一个 data-based 标识符首先为未知系统动力学被构造。由介绍... 为有致动器浸透和未知动力学的分离时间的系统的一个班的一个新奇最佳的追踪控制方法在这份报纸被建议。计划基于反复的适应动态编程(自动数据处理) 算法。以便实现控制计划,一个 data-based 标识符首先为未知系统动力学被构造。由介绍 M 网络,稳定的控制的明确的公式被完成。以便消除致动器浸透的效果, nonquadratic 表演功能被介绍,然后一个反复的自动数据处理算法被建立与集中分析完成最佳的追踪控制解决方案。为实现最佳的控制方法,神经网络被用来建立 data-based 标识符,计算性能索引功能,近似最佳的控制政策并且分别地解决稳定的控制。模拟例子被提供验证介绍最佳的追踪的控制计划的有效性。 展开更多
关键词 最优跟踪控制 离散时间系统 饱和执行器 DP算法 控制方案 神经网络 性能指标 系统动力学
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Percentile-based Neighborhood Precipitation Verification and Its Application to a Landfalling Tropical Storm Case with Radar Data Assimilation 被引量:3
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作者 ZHU Kefeng YANG Yi Ming XUE 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2015年第11期1449-1459,共11页
The traditional threat score based on fixed thresholds for precipitation verification is sensitive to intensity forecast bias. In this study, the neighborhood precipitation threat score is modified by defining the thr... The traditional threat score based on fixed thresholds for precipitation verification is sensitive to intensity forecast bias. In this study, the neighborhood precipitation threat score is modified by defining the thresholds in terms of the percentiles of overall precipitation instead of fixed threshold values. The impact of intensity forecast bias on the calculated threat score is reduced. The method is tested with the forecasts of a tropical storm that re-intensified after making landfall and caused heavy flooding. The forecasts are produced with and without radar data assimilation. The forecast with assimilation of both radial velocity and reflectivity produce precipitation patterns that better match observations but have large positive intensity bias. When using fixed thresholds, the neighborhood threat scores fail to yield high scores for forecasts that have good pattern match with observations, due to large intensity bias. In contrast, the percentile-based neighborhood method yields the highest score for the forecast with the best pattern match and the smallest position error. The percentile-based method also yields scores that are more consistent with object-based verifications, which are less sensitive to intensity bias, demonstrating the potential value of percentile-based verification. 展开更多
关键词 neighborhood precipitation threat score percentile-based verification radar data assimilation
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